Scholar : International Journal of Oncology - Volume:50 Number:4

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TABLE OF CONTENTS April-2017 Volume 50 Issue 4

The one-carbon metabolism pathway highlights therapeutic targets for gastrointestinal cancer (Review) Masamitsu Konno, Ayumu Asai, Koichi Kawamoto, Naohiro Nishida, Taroh Satoh, Yuichiro Doki, Masaki Mori, Hideshi Ishii View Abstract ❯

Apoptosis is augmented in high-grade serous ovarian cancer by the combined inhibition of Bcl-2/Bcl-xL and PARP Takuhei Yokoyama, Elise C. Kohn, Ethan Brill, Jung-Min Lee View Abstract ❯

A liquid biopsy-based method for the detection and quantification of circulating tumor cells in surgical osteosarcoma patients Haoqiang Zhang, Peng Gao, Xin Xiao, Michal Heger, Lei Geng, Bo Fan, Yulin Yuan, Chen Huang, Guojing Chen, Yao Liu, Yongchen Hu, Xiuchun Yu, Sujia Wu, Ling Wang, Zhen Wang View Abstract ❯

Overexpression of miRNA-221 promotes cell proliferation by targeting the apoptotic protease activating factor-1 and indicates a poor prognosis in ovarian cancer Jie Li, Qiang Li, He Huang, Yinguang Li, Li Li, Wenhui Hou, Zeshan You View Abstract ❯

miR‑150 inhibits proliferation and tumorigenicity via retarding G1/S phase transition in nasopharyngeal carcinoma Xiangyong Li, Fumei Liu, Bihua Lin, Haiqing Luo, Meilian Liu, Jinhua Wu, Caihong Li, Ronggang Li, Xin Zhang, Keyuan Zhou, Dong Ren View Abstract ❯

miR-21 and KLF4 jointly augment epithelial‑mesenchymal transition via the Akt/ERK1/2 pathway Chen-Hai Liu, Qiang Huang, Zhi-Yuan Jin, Cheng-Lin Zhu, Zhen Liu, Chao Wang View Abstract ❯

UBE2C induces EMT through Wnt/β‑catenin and PI3K/Akt signaling pathways by regulating phosphorylation levels of Aurora-A Rui Wang, Yue Song, Xi Liu, Qixue Wang, Yunfei Wang, Liwei Li, Chunsheng Kang, Qingyu Zhang View Abstract ❯

Dual roles of protein tyrosine phosphatase kappa in coordinating angiogenesis induced by pro-angiogenic factors Ping-Hui Sun, Gang Chen, Malcolm Mason, Wen G. Jiang, Lin Ye View Abstract ❯

Deubiquitinating enzyme USP20 is a positive regulator of Claspin and suppresses the malignant characteristics of gastric cancer cells Chao Wang, Chen Yang, Jun Ji, Jinling Jiang, Min Shi, Qu Cai, Yingyan Yu, Zhenggang Zhu, Jun Zhang View Abstract ❯

Gene expression profiling in bladder cancer identifies potential therapeutic targets Syed A. Hussain, Daniel H. Palmer, Wing-Kin Syn, Joseph J. Sacco, Richard M.D. Greensmith, Taha Elmetwali, Vijay Aachi, Bryony H. Lloyd, Puthen V. Jithesh, John Arrand, Darren Barton, Jawaher Ansari, D. Ross Sibson, Nicholas D. James View Abstract ❯

N-terminal polypeptide derived from vMIP-II exerts its antitumor activity by inhibiting the CXCR4 pathway in human glioma Qingling Yang, Haihua Wu, Haifeng Wang, Yu Li, Lingyu Zhang, Lihua Zhu, Wenrui Wang, Jihong Zhou, Yingxiao Fu, Sulian Chen, Qiong Wu, Changjie Chen, Congzhao Zhou View Abstract ❯

Design, synthesis and pharmaco-toxicological assessment of 5-mercapto-1,2,4-triazole derivatives with antibacterial and antiproliferative activity Marius Mioc, Codruta Soica, Vasile Bercean, Sorin Avram, Mihaela Balan‑Porcarasu, Dorina Coricovac, Roxana Ghiulai, Delia Muntean, Florina Andrica, Cristina Dehelean, Demetrios A. Spandidos, Aristides M. Tsatsakis, Ludovic Kurunczi View Abstract ❯

High stathmin 1 expression is associated with poor prognosis and chemoradiation resistance in esophageal squamous cell carcinoma Shigemasa Suzuki, Takehiko Yokobori, Bolag Altan, Keigo Hara, Daigo Ozawa, Naritaka Tanaka, Makoto Sakai, Akihiko Sano, Makoto Sohda, Halin Bao, Minoru Fukuchi, Tatsuya Miyazaki, Kyoichi Kaira, Takayuki Asao, Hiroyuki Kuwano View Abstract ❯

Inflammatory peroxidases promote breast cancer progression in mice via regulation of the tumour microenvironment Vasilios Panagopoulos, Damien A. Leach, Irene Zinonos, Vladimir Ponomarev, Giovanni Licari, Vasilios Liapis, Wendy V. Ingman, Peter Anderson, Mark O. DeNichilo, Andreas Evdokiou View Abstract ❯

Enhanced expression of α2,3-linked sialic acids promotes gastric cancer cell metastasis and correlates with poor prognosis Li Shen, Zhiguo Luo, Junbo Wu, Li Qiu, Ming Luo, Qing Ke, Xiaoxia Dong View Abstract ❯

miR-940 upregulation contributes to human cervical cancer progression through p27 and PTEN inhibition Ke Su, Chun-Fang Wang, Ying Zhang, Yu-Jie Cai, Yan-Yan Zhang, Qian Zhao View Abstract ❯

Rb deficiency accelerates progression of carcinoma of the urinary bladder in vivo and in vitro through inhibiting autophagy and apoptosis Cheng-Yuan Wang, Zhi-Bin Xu, Jiang-Ping Wang, Yong Jiao, Bo Zhang View Abstract ❯

HCRP1 inhibits TGF-β induced epithelial-mesenchymal transition in hepatocellular carcinoma Wenlin Yang, Ji-Gang Wang, Jiawen Xu, Danmei Zhou, Kehan Ren, Chenjian Hou, Linlin Chen, Xiuping Liu View Abstract ❯

Silencing of FANCD2 enhances the radiosensitivity of metastatic cervical lymph node-derived head and neck squamous cell carcinoma HSC-4 cells Hua-Jun Feng, Yi-Lin Bao, Zhuo-Ping Liang, Fei-Peng Zhao, Sheng-En Xu, Wei Xu, Chong Zhao, Gang Qin View Abstract ❯

Silencing Snail suppresses tumor cell proliferation and invasion by reversing epithelial-to-mesenchymal transition and arresting G2/M phase in non-small cell lung cancer Xueying Yang, Mengmeng Han, Haibo Han, Bingjing Wang, Sheng Li, Zhiqian Zhang, Wei Zhao View Abstract ❯

The nerve growth factor alters calreticulin translocation from the endoplasmic reticulum to the cell surface and its signaling pathway in epithelial ovarian cancer cells Carolina Andrea Vera, Lorena Oróstica, Fernando Gabler, Arturo Ferreira, Alberto Selman, Margarita Vega, Carmen Aurora Romero View Abstract ❯

HOTAIR upregulates an 18-gene cell cycle-related mRNA network in glioma Kai Huang, Jia Sun, Chao Yang, Yunfei Wang, Bingcong Zhou, Chunsheng Kang, Lei Han, Qixue Wang View Abstract ❯

Selective FGFR inhibitor BGJ398 inhibits phosphorylation of AKT and STAT3 and induces cytotoxicity in sphere-cultured ovarian cancer cells Hwa Jun Cha, Jung Hye Choi, In Chul Park, Chun Ho Kim, Sung Kwan An, Tae Jin Kim, Jae Ho Lee View Abstract ❯

Molecular mechanism of C-reaction protein in promoting migration and invasion of hepatocellular carcinoma cells in vitro Shasha Shen, Jiaojiao Gong, Yixuan Yang, Si Qin, Lifan Huang, Sha She, Min Yang, Hong Ren, Huaidong Hu View Abstract ❯

Quercetin nanoparticles display antitumor activity via proliferation inhibition and apoptosis induction in liver cancer cells Ke-Wei Ren, Ya-Hua Li, Gang Wu, Jian-Zhuang Ren, Hui-Bin Lu, Zong-Ming Li, Xin-Wei Han View Abstract ❯

Ectopic expression of the ATP synthase β subunit on the membrane of PC-3M cells supports its potential role in prostate cancer metastasis Wei Li, Yulin Li, Gaiyun Li, Zilong Zhou, Xiaona Chang, Yang Xia, Xinjie Dong, Zhijing Liu, Bo Ren, Wei Liu, Yilei Li View Abstract ❯

Curcumin reverses benzidine-induced epithelial-mesenchymal transition via suppression of ERK5/AP-1 in SV-40 immortalized human urothelial cells Zhiqi Liu, Jie Liu, Li Zhao, Hao Geng, Jiaxing Ma, Zhiqiang Zhang, Dexin Yu, Caiyun Zhong View Abstract ❯

Ursolic acid nanoparticles inhibit cervical cancer growth in vitro and in vivo via apoptosis induction Shaoguang Wang, Xiaomei Meng, Yaozhong Dong View Abstract ❯

Suppression of cancer stem-like phenotypes in NCI-H460 lung cancer cells by vanillin through an Akt-dependent pathway Songpol Srinual, Pithi Chanvorachote, Varisa Pongrakhananon View Abstract ❯

Furin promotes epithelial-mesenchymal transition in pancreatic cancer cells via Hippo-YAP pathway Youli Zhang, Meng Zhou, Hong Wei, Hailang Zhou, Junbo He, Ying Lu, Dawei Wang, Baoding Chen, Jian Zeng, Wanxin Peng, Fengyi Du, Aihua Gong, Min Xu View Abstract ❯

All-trans retinoic acid restored the osteogenic ability of BMP9 in osteosarcoma through the p38 MAPK pathway Nian Wu, Ruidong Li, Zijun Meng, Mao Nie, Qianzhao Chen, Baicheng He, Zhongliang Deng, Liangjun Yin View Abstract ❯

SF-KDM2A binds to ribosomal RNA gene promoter, reduces H4K20me3 level, and elevates ribosomal RNA transcription in breast cancer cells Kengo Okamoto, Yuji Tanaka, Makoto Tsuneoka View Abstract ❯

miR-28-5p promotes the development and progression of ovarian cancer through inhibition of N4BP1 Juan Xu, Nan Jiang, Haijuan Shi, Shanshan Zhao, Shuzhong Yao, Huimin Shen View Abstract ❯

3-Hydroxyterphenyllin, a natural fungal metabolite, induces apoptosis and S phase arrest in human ovarian carcinoma cells Yaomin Wang, Casey Compton, Gary O. Rankin, Stephen J. Cutler, Yon Rojanasakul, Youying Tu, Yi Charlie Chen View Abstract ❯

Inhibin-α gene mutations and mRNA levels in human lymphoid and myeloid leukemia cells Young Il Kim, Seung-Won Park, Hye Shin Kwon, Hyung-Seok Yang, Sun Young Cho, Young Jin Kim, Hee Joo Lee View Abstract ❯

Expression and prognostic value of the cell polarity PAR complex members in thyroid cancer Chiara Tuccilli, Enke Baldini, Yannick Arlot-Bonnemains, Frank Chesnel, Salvatore Sorrenti, Corrado De Vito, Eleonora D'Armiento, Alessandro Antonelli, Poupak Fallahi, Sara Watutantrige, Francesco Tartaglia, Susi Barollo, Caterina Mian, Stefano Arcieri, Domenico Mascagni, Daniele Pironi, Marco Bononi, Massimo Vergine, Massimo Monti, Angelo Filippini, Salvatore Ulisse View Abstract ❯

Effects of irradiation on human leukocyte antigen class I expression in human papillomavirus positive and negative base of tongue and mobile tongue squamous cell carcinoma cell lines Linnea Haeggblom, Cecilia Nordfors, Nikolaos Tertipis, Cinzia Bersani, Torbjörn Ramqvist, Anders Näsman, Tina Dalianis View Abstract ❯

Targeting glutamine metabolism and the focal adhesion kinase additively inhibits the mammalian target of the rapamycin pathway in spheroid cancer stem-like properties of ovarian clear cell carcinoma in vitro Masakazu Sato, Kei Kawana, Katsuyuki Adachi, Asaha Fujimoto, Mitsuyo Yoshida, Hiroe Nakamura, Haruka Nishida, Tomoko Inoue, Ayumi Taguchi, Juri Ogishima, Satoko Eguchi, Aki Yamashita, Kensuke Tomio, Osamu Wada-Hiraike, Katsutoshi Oda, Takeshi Nagamatsu, Yutaka Osuga, Tomoyuki Fujii View Abstract ❯

Matrix stiffness regulates the proliferation, stemness and chemoresistance of laryngeal squamous cancer cells Lian Hui, Jingru Zhang, Xiaoxu Ding, Xing Guo, Xuejun Jiang View Abstract ❯

Therapeutic effects of Schisandra chinensis on the hyperprolactinemia in rat So-Hye Hong, Mei Li, Eui-Bae Jeung, Geun-Shik Lee, Eui-Ju Hong, Young-Whan Choi, Beum-Soo An View Abstract ❯

[Corrigendum] Promoter methylation of RASSF1A modulates the effect of the microtubule-targeting agent docetaxel in breast cancer Eun Young Gil, Uk Hyun Jo, Hoiseon Jeong, Young Mi Whang, Ok Hee Woo, Kyu Ran Cho, Jae Hong Seo, Aeree Kim, Eun Sook Lee, Insong Koh, Yeul Hong Kim, Kyong Hwa Park View Abstract ❯

5-7 October, 2017, Metropolitan Hotel, Athens, Greece 22nd World Congress on Advances in Oncology & 20th International Symposium on Molecular Medicine 3-4 October 2017, Pre-Congress Workshop: 'Next-Generation Sequencing – Library construction and quality control'

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Cell type-specific regulatory effects of glucocorticoids on cutaneous TLR2 expression and signalling

Publication date: Available online 2 April 2017
Source:The Journal of Steroid Biochemistry and Molecular Biology
Author(s): Qi Su, Anja Pfalzgraff, Günther Weindl
Glucocorticoids (GCs) induce Toll-like receptor (TLR) 2 expression and synergistically upregulate TLR2 with pro-inflammatory cytokines or bacteria. These paradoxical effects have drawn attention to the inflammatory initiating or promoting effects of GCs, as GC treatment can provoke inflammatory skin diseases. Here, we aimed to investigate the regulatory effects of GCs in human skin cells of different epidermal and dermal layers. We found that Dex induced TLR2 expression mainly in undifferentiated and less in calcium-induced differentiated keratinocytes but not in HaCaT cells or fibroblasts, however, Dex reduced TLR1/6 expression. Stimulation with Dex under inflammatory conditions further increased TLR2 but not TLR1 or TLR6 levels in keratinocytes. Increased ligand-induced interaction of TLR2 with MyD88 and expression of the adaptor protein TRAF6 indicated enhanced TLR2 signalling, whereas TLR2/1 or TLR2/6 signalling was not increased in Dex-pretreated keratinocytes. GC-increased TLR2 expression was negatively regulated by JNK MAPK signalling when stimulated with Propionibacterium acnes. Our results provide novel insights into the molecular mechanisms of glucocorticoid-mediated expression and function of TLR2 in human skin cells and the understanding of the mechanisms of corticosteroid side effects.

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Frontmatter

Journal Name: Journal of Pediatric Endocrinology and Metabolism
Volume: 30
Issue: 4
Pages: i-iv

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Pediatric endocrinology is pediatrics is public health

Journal Name: Journal of Pediatric Endocrinology and Metabolism
Volume: 30
Issue: 4
Pages: 371-374

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Total body fat, abdominal fat, body fat distribution and surrogate markers for health related to adipocyte fatty acid-binding protein (FABP4) in children

Journal Name: Journal of Pediatric Endocrinology and Metabolism
Volume: 30
Issue: 4
Pages: 375-382

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Vitamin D supplementation, the metabolic syndrome and oxidative stress in obese children

Journal Name: Journal of Pediatric Endocrinology and Metabolism
Volume: 30
Issue: 4
Pages: 383-388

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Vitamin D status in Egyptian children with type 1 diabetes and the role of vitamin D replacement in glycemic control

Journal Name: Journal of Pediatric Endocrinology and Metabolism
Volume: 30
Issue: 4
Pages: 389-394

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Cross-sectional analysis of universal vitamin D supplementation in former East Germany during the first year of life

Journal Name: Journal of Pediatric Endocrinology and Metabolism
Volume: 30
Issue: 4
Pages: 395-404

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Ethnicity and incidence of congenital hypothyroidism in the capital of Macedonia

Journal Name: Journal of Pediatric Endocrinology and Metabolism
Volume: 30
Issue: 4
Pages: 405-409

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Changes of thyroid hormonal status in patients receiving ketogenic diet due to intractable epilepsy

Journal Name: Journal of Pediatric Endocrinology and Metabolism
Volume: 30
Issue: 4
Pages: 411-416

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Leptin and adiponectin levels in discordant dichorionic twins at 72 hours of age-associations with anthropometric parameters and insulin resistance

Journal Name: Journal of Pediatric Endocrinology and Metabolism
Volume: 30
Issue: 4
Pages: 417-426

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Analysis of growth hormone receptor gene expression in tall and short stature children

Journal Name: Journal of Pediatric Endocrinology and Metabolism
Volume: 30
Issue: 4
Pages: 427-430

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Clinical features of girls with short stature among inv (9), Turner (45, X) and control individuals

Journal Name: Journal of Pediatric Endocrinology and Metabolism
Volume: 30
Issue: 4
Pages: 431-436

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Hereditary vitamin D-resistant rickets in Lebanese patients: the p.R391S and p.H397P variants have different phenotypes

Journal Name: Journal of Pediatric Endocrinology and Metabolism
Volume: 30
Issue: 4
Pages: 437-444

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Associations between obesity, adverse behavioral patterns and cardiovascular risk factors among adolescent inhabitants of a Greek island

Journal Name: Journal of Pediatric Endocrinology and Metabolism
Volume: 30
Issue: 4
Pages: 445-454

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Increase of body mass index (BMI) from 1.5 to 3 years of age augments the degree of insulin resistance corresponding to BMI at 12 years of age

Journal Name: Journal of Pediatric Endocrinology and Metabolism
Volume: 30
Issue: 4
Pages: 455-457

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The variable clinical phenotype of three patients with hepatic glycogen synthase deficiency

Journal Name: Journal of Pediatric Endocrinology and Metabolism
Volume: 30
Issue: 4
Pages: 459-462

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Molecular defects identified by whole exome sequencing in a child with atypical mucopolysaccharidosis IIIB

Journal Name: Journal of Pediatric Endocrinology and Metabolism
Volume: 30
Issue: 4
Pages: 463-469

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Clinical presentation and treatment response to diazoxide in two siblings with congenital hyperinsulinism as a result of a novel compound heterozygous ABCC8 missense mutation

Journal Name: Journal of Pediatric Endocrinology and Metabolism
Volume: 30
Issue: 4
Pages: 471-474

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Cushing’s syndrome in infancy due to ectopic ACTH secretion by a sacro-coccygeal teratoma

Journal Name: Journal of Pediatric Endocrinology and Metabolism
Volume: 30
Issue: 4
Pages: 475-478

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Growth-hormone deficiency in mitochondrial disorders

Journal Name: Journal of Pediatric Endocrinology and Metabolism
Volume: 30
Issue: 4
Pages: 479-481

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Response to Growth hormone deficiency in mitochondrial disorders

Journal Name: Journal of Pediatric Endocrinology and Metabolism
Volume: 30
Issue: 4
Pages: 483-484

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Objective Measurement of Clinical Competency in Surgical Education Using Electrodermal Activity

Publication date: Available online 1 April 2017
Source:Journal of Surgical Education
Author(s): Jacob A. Quick, Alex D. Bukoski, Jennifer Doty, Bethany J. Bennett, Megan Crane, Stephen L. Barnes
ObjectiveWithin the realm of surgical education, there is a need for objective means to determine surgical competence and resident readiness to operate independently. We propose a novel, objective method of assessing resident confidence and clinical competence based on measurement of electrodermal activity (EDA) during live surgical procedures. We hypothesized that with progressive training, EDA responses to the stress of performing surgery would exhibit decline, elucidating an objective correlate of clinical competence.DesignEDA was measured using galvanic skin response sensors worn by residents performing laparoscopic cholecystectomy on sequential live human patients over an 8-month period. Baseline, phasic (peak) and tonic EDA responses were measured as a fractional change from baseline.SettingUniversity of Missouri, Columbia, Missouri, an academic tertiary care facility.ParticipantsFourteen categorical general surgery residents and 5 faculty surgeons were voluntarily enrolled and participated through completion.ResultsTonic fractional change (FCTONIC) was highest in PGY3 residents compared with postgraduate year (PGY) 1 and 2 residents (7.199 vs. 2.100, p = 0.004, 95% CI: 8.58-1.61 and PGY4 and 5 residents (7.199 vs. 2.079, p = 0.002, 95% CI: 8.38-0.29). Phasic fractional change in EDA (FCPHASIC) exhibited a progressive decline across resident training levels, with PGY1 and 2 residents having the highest response, and faculty displaying the lowest FCPHASIC responses. Statistical differences were seen between FCPHASIC faculty and PGY4 and 5 (3.596 vs. 6.180, p = 0.004, 95% CI: 0.80-4.36), PGY4 and 5, and PGY3 (6.180 vs. 15.998, p = 0.003, 95% CI: 3.33-16.3), as well as among all residents and faculty (13.057 vs. 3.596, p = 0.004, 95% CI: 15.8-3.1).ConclusionPhasic EDA changes decrease with increasing clinical competence. For those participants with the lowest and highest levels of competence, tonic EDA changes are minimal. Tonic EDA changes follow an inverse-U shape with differing levels of clinical competence.



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Palliative systemic therapy for recurrent or metastatic nasopharyngeal carcinoma − how far have we achieved?

Publication date: Available online 2 April 2017
Source:Critical Reviews in Oncology/Hematology
Author(s): Victor Lee, Dora Kwong, To-Wai Leung, Ka-On Lam, Chi-Chung Tong, Anne Lee
Nasopharyngeal carcinoma (NPC) is endemic in Southern China, Taiwan, Malaysia, Singapore, North Africa and Alaska. About 30% of NPC patients develop recurrence or metastasis despite initial radical treatment. Palliative chemotherapy is the first-line treatment for inoperable recurrence or distant metastatic disease. However the standard first-line chemotherapeutic regimen is yet to be established until recently gemcitabine and cisplatin has been proven superior to traditional regimen with 5-FU and cisplatin shown in a phase III randomized-controlled trial. Further palliative systemic treatment options including other chemotherapeutic regimens, targeted therapy and more recently immunotherapy have gradually evolved. We provided a comprehensive review on different traditional chemotherapeutic regimens and highlighted the latest chemotherapeutic treatments as well as the latest development of targeted therapies, immune checkpoint inhibitors and other immunotherapeutic options in this setting.



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Selective scene perception deficits in a case of topographical disorientation

Publication date: Available online 2 April 2017
Source:Cortex
Author(s): Jessica Robin, Matthew X. Lowe, Sara Pishdadian, Josée Rivest, Jonathan S. Cant, Morris Moscovitch
Topographical disorientation (TD) is a neuropsychological condition characterized by an inability to find one's way, even in familiar environments. One common contributing cause of TD is landmark agnosia, a visual recognition impairment specific to scenes and landmarks. Although many cases of TD with landmark agnosia have been documented, little is known about the perceptual mechanisms which lead to selective deficits in recognizing scenes. In the present study, we test LH, a man who exhibits TD and landmark agnosia, on measures of scene perception that require selectively attending to either the configural or surface properties of a scene. Compared to healthy controls, LH demonstrates perceptual impairments when attending to the configuration of a scene, but not when attending to its surface properties, such as the pattern of the walls or whether the ground is sand or grass. In contrast, when focussing on objects instead of scenes, LH demonstrates intact perception of both geometric and surface properties. This study demonstrates that in a case of TD and landmark agnosia, the perceptual impairments are selective to the layout of scenes, providing insight into the mechanism of landmark agnosia and scene-selective perceptual processes.



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Solidification of floating organic droplet in dispersive liquid-liquid microextraction as a green analytical tool

Publication date: 1 August 2017
Source:Talanta, Volume 170
Author(s): Fotouh R. Mansour, Neil D. Danielson
Dispersive liquid-liquid microextraction (DLLME) is a special type of microextraction in which a mixture of two solvents (an extracting solvent and a disperser) is injected into the sample. The extraction solvent is then dispersed as fine droplets in the cloudy sample through manual or mechanical agitation. Hence, the sample is centrifuged to break the formed emulsion and the extracting solvent is manually separated. The organic solvents commonly used in DLLME are halogenated hydrocarbons that are highly toxic. These solvents are heavier than water, so they sink to the bottom of the centrifugation tube which makes the separation step difficult. By using solvents of low density, the organic extractant floats on the sample surface. If the selected solvent such as undecanol has a freezing point in the range 10–25°C, the floating droplet can be solidified using a simple ice-bath, and then transferred out of the sample matrix; this step is known as solidification of floating organic droplet (SFOD). Coupling DLLME to SFOD combines the advantages of both approaches together. The DLLME-SFOD process is controlled by the same variables of conventional liquid-liquid extraction. The organic solvents used as extractants in DLLME-SFOD must be immiscible with water, of lower density, low volatility, high partition coefficient and low melting and freezing points. The extraction efficiency of DLLME-SFOD is affected by types and volumes of organic extractant and disperser, salt addition, pH, temperature, stirring rate and extraction time. This review discusses the principle, optimization variables, advantages and disadvantages and some selected applications of DLLME-SFOD in water, food and biomedical analysis.

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Determination of Escherichia coli in urine using a low-cost foil-based microfluidic device

Publication date: 1 August 2017
Source:Talanta, Volume 170
Author(s): Tereza Mašková, Lenka Hárendarčíková, Jan Petr
We developed a simple low-cost cultivation-based microfluidic device from office-laminator foil and Parafilm for the determination of specific microorganisms in water samples. The main goal was to obtain a device that would be portable and cheap compared to common laboratory techniques testing microorganisms. This device needs only 10µL of a sample and can be easily used in terrain by a non-specialist. Moreover, we dealt with some technical aspects of the device fabrication such as low-cost lamination techniques and the use of different cultivation media.

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High selective potentiometric sensor for determination of nanomolar con-centration of Cu(II) using a polymeric electrode modified by a graphene/7,7,8,8-tetracyanoquinodimethane nanoparticles

Publication date: 1 August 2017
Source:Talanta, Volume 170
Author(s): Magdalena Pięk, Katarzyna Fendrych, Joanna Smajdor, Robert Piech, Beata Paczosa-Bator
In this paper we present several possibilities for modification of the all-solid-state copper(II)-selective electrodes in order to obtain high stability and selectivity potentiometric sensor signal. The copper(II)-selective electrodes were modified in a simple way by introducing solid contact layer based on graphene or graphene oxide, 7,7,8,8-tetracyanoquinodimethane or its copper salt. Each of electrodes shown a Nernstian response, wide linear range of Cu²⁺ concentration and a low detection limit. Nevertheless, some differences between the groups of electrodes have been noticed and resulted from application of intermediate layers of various compositions. The electrode modified with graphene and 7,7,8,8-tetracyanoquinodimethane nanocomposite exhibited the best potential reproducibility and detection limit. Moreover, prepared sensors were characterized by an improved selectivity for copper(II) in relation to non-modified electrodes. The developed electrodes were successfully used for the Cu²⁺ determination in different samples and results were comparable with those obtained using voltammetry.

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Waste derivitized blue luminescent carbon quantum dots for selenite sensing in water

Publication date: 1 August 2017
Source:Talanta, Volume 170
Author(s): Pooja Devi, Gurvinder Kaur, Anupma Thakur, Navneet Kaur, Anita Grewal, Praveen Kumar
Herein, we report an environmental friendly, facile, and completely green synthetic method for producing carbon quantum dots (CQDs) from whey, a major dairy waste. The as-prepared monodispersed diameter CQDs exhibit blue luminescence with noteworthy quantum yield (~11.4%) and excitation dependent emission behaviour. Nuclear magnetic resonance (NMR) analysis reveals the presence of aromatized carbon peaks, leading to polymerized CQDs diameter architecture during whey pyrolysis. The X-ray and selected area electron diffraction patterns confirm their amorphous nature. Further, we demonstrate, these CQDs as an effective sensor probe for selective selenite monitoring in water upon functionalization with appropriate ligand. The functionalized GCQDs probe is shown to detect selenite with high sensitivity in 10–1000ppb detection range. Further it is selective for selenite over other relevant ions (such as Cu²⁺, As³⁺, As⁵⁺, Pb²⁺, Ni²⁺, Se⁶⁺, Cl^-, Br^-, NO3⁻, NO2⁻ and F⁻) and displays a sub-ppb detection limit at 1.1% relative standard deviation.

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Antibacterial activity of medicinal plants from The Physicians of Myddvai, a 13th century Welsh medical manuscript

Publication date: 5 May 2017
Source:Journal of Ethnopharmacology, Volume 203
Author(s): Charles Stephen Wagner, Jillian De Gezelle, Maureen Robertson, Keith Robertson, Mickey Wilson, Slavko Komarnytsky
Ethnopharmacological relevanceAntimicrobial drug resistance is a growing threat to global public health. Historical records and herbal texts relating to traditional Celtic medicine indicate an extensive pharmacopeia of plants for treating infections likely caused by microbes. However, a major barrier for successful integration of these remedies into mainstream practice is the current lack of accurate interpretation and scientific validation.Materials and methodsWe investigated the flora of the Isle of Arran, Scotland, via in situ targeted screening of 83 out of 138 plants identified in Meddygion Myddvai (a 13^th century Welsh manuscript) to treat conditions related to microbial infections, and an additional 18 plants from modern ethnobotanical knowledge on the island (Scottish School of Herbal Medicine). In a follow-up proof-of-concept study, bioassay-guided fractionation was performed to identify bioactive constituents from two high scoring hits that inhibited Staphylococcus aureus (Gram-positive) and Escherichia coli (Gram-negative) bacterial growth.Results67 historical plants (80.7%) and 14 modern plants (77.8%) were found to have detectable levels of antimicrobial activity when tested using Mobile Discovery kits, with human saliva as a source of bacteria for screening. Sabinene, a natural bicyclic monoterpene from juniper "berries" (Juniperus communis L.) and alliin, a natural sulfoxide from garlic cloves (Allium sativum L.), were isolated and confirmed as primary antibacterial leads.ConclusionUsing historical medical sources such as those associated with traditional Celtic medicine to guide rigorous, evidence-based scientific investigation, provides additional leads for new and alternative bioactive molecules for combating bacterial diseases.

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The assessment of the chronic hepatotoxicity induced by Polygoni Multiflori Radix in rats: A pilot study by using untargeted metabolomics method

Publication date: 5 May 2017
Source:Journal of Ethnopharmacology, Volume 203
Author(s): Xin-Hua Xia, Yuan-Yuan Yuan, Mei Liu
Polygoni Multiflori Radix is the dried root of Polygonum multiflorum Thunb officially recorded in the Chinese Pharmacopoeia as HeShouWu (HSW) in Chinese pinyin. The processed HSW are commonly used in TCM to treat liver disease and Chinese Pharmacopoeia has described the actions of it to tonify liver-kidney, replenish essence and blood, blacken beard and hair, strengthen sinew and bone, and resolve turbidity and lower lipid hence making it use not only as a herbal medicine in TCM but also as supplementary food in health care.Aim of the studyConcerns about the hepatotoxicity in association with Polygoni Multiflori Radix and its processed products have been reported in some countries. In the present study, we aim to investigate the potential hepatotoxicity of HSW in rats with oral administration of 95% ethanol-extracts of Polygoni Multiflori Radix by using metabolomics method.Materials and methodsHere, male rats with 150–180g body weight were received vehicle control or Polygoni Multiflori Radix extracts (HSW-Ex) orally at 19.2 (low dose), 192 (medium dose), or 1920mg/kg/day (high dose), respectively, for 28 consecutive days. Signs of HSW-induced toxicity were monitored by traditional toxicity assessments (e.g., clinical pathology and histopathology). Metabolomics investigation of serum was performed to identify potential endogenous metabolites which may be relevant to liver injury.ResultsRats received High and Medium dose of HSW-Ex showed greater sign of liver injury with increased levels of ASP, ALT, and AST, as well as reduced SOD activity when compared to vehicle control. In contrast, there are no significant changes relevant to liver injury observed in rats by receiving the low dose of HSW-Ex. Metabolomics analyses have identified ten potential endogenous metabolites varied significantly among the treatment groups with varying doses of HSW-Ex, of which might be related to liver injury.ConclusionOur data has further suggested that liver damage resulting from HSW-Ex consumption is dosage dependent in rats. It is possible that disruption in amino acid and energy metabolism might lead to subsequent oxidative damage in the liver of rats. Because the clinic practice often use low dose in a short time, therefore HSW usage in TCM still keep safe currently, but we present a warning to the clinical doctors and make them has some concern about high dose of HSW usage in a long term that has potential danger to damage liver.

Graphical abstract

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Hydroethanolic extract from Echinodorus scaber Rataj leaves inhibits inflammation in ovalbumin-induced allergic asthma

Publication date: 5 May 2017
Source:Journal of Ethnopharmacology, Volume 203
Author(s): Suellen Iara Guirra Rosa, Fabrício Rios-Santos, Sikiru Olaitan Balogun, Danielle Ayr Tavares de Almeida, Amilcar Sabino Damazo, Thais Campos Dias da Cruz, Eduarda Pavan, Robson dos Santos Barbosa, Tarso da Costa Alvim, Ilsamar Mendes Soares, Sérgio Donizeti Ascêncio, Antonio Macho, Domingos Tabajara de Oliveira Martins
Ethnopharmacological relevanceEchinodorus scaber, Alismataceae, is popularly known in Brazil as "chapéu-de-couro". The plant leaves are used by the population as decoction, infusion, or maceration in bottled spirits, to treat inflammatory respiratory diseases.Aim of the studyTo investigate the anti-inflammatory mechanism of the hydroethanolic extract of leaves of Echinodorus scaber (HEEs) in allergic asthma. A phytochemical analysis of the extract was performed as well.Materials and methodsThe leaves of Echinodorus scaber were prepared by maceration in 75% ethanol. Preliminary phytochemical analysis was carried out using basic classical methods, and the secondary metabolites detected in HEEs were analyzed and confirmed by high-performance liquid chromatography (HPLC). The in vivo anti-inflammatory activity of HEEs was evaluated in Swiss male albino mice sensitized and challenged by OVA. The HEEs (1, 5 and 30mg/kg, p.o.) was administered to mice twice a day, 1h before the challenge, from days 19 through 24. The mechanism of action of HEEs was studied by evaluating the levels of TH2 cytokines (IL-4, IL-5 and IL-13) in bronchoalveolar lavage fluid (BALF) and IgE production in blood plasma. Histopathological changes triggered by OVA-sensitization/challenge in the lung tissue were also investigated.ResultsHEEs reduced total leukocyte, eosinophil, neutrophil, and mononuclear cell counts at all doses tested, with maximum effect at 30mg/kg (73.9%, 75.9%, 75.5%, and 65.2% reduction, p<0.001, respectively). Increases in TH2 cytokine secretion (IL-4, IL-5 and IL-13) and in IgE levels were also attenuated by HEEs. Preliminary phytochemical screening seems to indicated the presence of phenolic compounds, flavonoids and alkaloids. HPLC analyses evidenced the presence of phenolic compounds, such as gallic acid, rutin and vitexin.ConclusionOur findings provided pharmacological preclinical evidence for the popular use of the leaves of Echinodorus scaber in allergic inflammation. Its anti-inflammatory effect was dependent on the decrease in migratory inflammatory cells, and both TH2 cytokines and IgE levels. It is suggested that vitexin, gallic acid and rutin, known anti-inflammatory compounds, may participate in the anti-asthamtic effect of the HEEs, by acting jointly along with other components present in the extract.

Graphical abstract

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The Association of Neuromuscular Attributes with Performance-based Mobility among Community-dwelling Older Adults with Symptomatic Lumbar Spinal Stenosis

Publication date: Available online 2 April 2017
Source:Archives of Physical Medicine and Rehabilitation
Author(s): Catherine T. Schmidt, Rachel E. Ward, Pradeep Suri, Dan K. Kiely, Ni Pensheng, Dennis E. Anderson, Jonathan F. Bean
ObjectiveTo identify differences in health factors, neuromuscular attributes and performance-based mobility among community-dwelling older adults with symptomatic lumbar spinal stenosis (SLSS); and to determine which neuromuscular attributes are associated with performance-based measures of mobility. We hypothesized that: (1) community-dwelling older adults with SLSS would have poorer health, greater neuromuscular impairment and worse mobility; and (2) greater impairment in trunk extensor muscle endurance, leg strength, leg speed and knee flexion range of motion (ROM) would be associated with performance-based mobility. Design: Cross-sectional; secondary data analysis of a cohort studySettingoutpatient rehabilitation centerParticipantsCommunity-dwelling adults > 65 years with self-reported mobility limitations and SLSSInterventionsN/AMain Outcome MeasuresShort Physical Performance Battery Score, Habitual Gait Speed, and Chair Stand TestResultsSLSS was classified using self-reported symptoms of neurogenic claudication and imaging. Among 430 community-dwelling older adults 54(13%) met criteria for SLSS. Compared to participants without SLSS, those with SLSS had more comorbidities, higher BMI, greater pain and less balance confidence. Participants with SLSS had greater impairment in trunk extensor muscle endurance, leg strength, leg strength asymmetry, knee flexion range of motion (ROM), knee extension ROM, and ankle ROM compared to participants without SLSS. Five neuromuscular attributes were associated with performance-based mobility among participants with SLSS: trunk extensor muscle endurance, leg strength, leg strength asymmetry, knee flexion ROM, and knee extension ROM asymmetry.ConclusionsCommunity-dwelling older adults with self-reported mobility limitations with SLSS exhibit poorer health characteristics, greater neuromuscular impairment and worse mobility when compared to those without SLSS. Poorer trunk extensor muscle endurance, leg strength, leg strength asymmetry, knee flexion ROM, and knee extension ROM asymmetry were associated with performance-based mobility among participants with SLSS.



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Effect of natural and semi-synthetic cadinanes from Heterotheca inuloides on NF-κB, Nrf2 and STAT3 signaling pathways and evaluation of their in vitro cytotoxicity in human cancer cell lines

Publication date: Available online 2 April 2017
Source:Bioorganic & Medicinal Chemistry
Author(s): Verónica Egas, Estrella Millán, Juan A. Collado, Teresa Ramírez-Apan, Carlos A. Méndez-Cuesta, Eduardo Muñoz, Guillermo Delgado
The effects of ten natural cadinane sesquiterpenoids isolated from Heterotheca inuloides on the pathways of the NF-κB, Nrf2 and STAT3 transcription factors were studied for the first time. The main constituent in this species, 7-hydroxy-3,4-dihydrocadalene (1), showed anti-NF-κB activity and activated the antioxidant Nrf2 pathway, which may explain the properties reported for the traditional use of the plant. In addition to the main metabolite, a structurally similar compound, 7-hydroxy-cadalene (2), also displayed anti-NF-κB activity. Thus, both natural compounds were used as templates for the preparation of a novel semi-synthetic derivative set, including esters and carbamates, which were evaluated for their potential in vitro antiproliferative activities against six human cancer cell lines. Carbamate derivatives 32 and 33 were found to exhibit potent activity against human colorectal adenocarcinoma and showed important selectivity in cancer cells. Among ester derivatives, compound 13 was determined to be a more potent NF-κB inhibitor and Nrf2 activator than its parent, 7-hydroxy-3,4-dihydrocadalene (1). Furthermore, this compound decreases levels of phospho-IκBα, a protein complex involved in the NF-κB activation pathway. Molecular simulations suggest that all active compounds interact with the activation loop of the IKKβ subunit in the IKK complex, which is the responsible of IκBα phosphorylation. Thus, we identified two natural, and one semi-synthetic, NF-κB and Nrf2 modulators and two new promising cytotoxic compounds.

Graphical abstract

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Editorial board

Publication date: 1 May 2017
Source:Bioorganic & Medicinal Chemistry, Volume 25, Issue 9





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Erratum to “Synthesis, biological evaluation, and physicochemical property assessment of 4-substituted 2-phenylaminoquinazolines as Mer tyrosine kinase inhibitors” [Bioorg. Med. Chem. 24 (2016) 3083–3092]

Publication date: 1 May 2017
Source:Bioorganic & Medicinal Chemistry, Volume 25, Issue 9
Author(s): Sheng-Biao Wang, Mu-Tian Cui, Xiao-Feng Wang, Emika Ohkoshi, Masuo Goto, De-Xuan Yang, Linna Li, Shoujun Yuan, Susan L. Morris-Natschke, Kuo-Hsiung Lee, Lan Xie




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Computational Refinement of Spectroscopic FRET Measurements

Publication date: Available online 2 April 2017
Source:Data in Brief
Author(s): Alexander Kyrychenko, Mykola V. Rodnin, Chiranjib Ghatak, Alexey S. Ladokhin
This article supplies raw data related to a research article entitled "Joint refinement of FRET measurements using spectroscopic and computational tools" (A. Kyrychenko, M. V.Rodnin, C. Ghatak, A. S. Ladokhin, 2017) [1], in which we demonstrate the use of molecular dynamics simulations to estimate FRET orientational factors in a benchmark donor-linker-acceptor system of enhanced cyan (ECFP) and enhanced yellow (EYFP) fluorescent proteins. This can improve the recalculation of donor-acceptor distance information from single-molecule FRET measurements.



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Multi-targeted protection of acetaminophen-induced hepatotoxicity in mice by tannic acid

Publication date: June 2017
Source:International Immunopharmacology, Volume 47
Author(s): Jianping Zhang, Qiongtao Song, Xue Han, Yuanyuan Zhang, Ying Zhang, Xuan Zhang, Xi Chu, Fenghua Zhang, Li Chu
Tannic acid (TA) is the polyphenol that has beneficial health effects against oxidative stress. However, the hepatoprotective effects of TA are still relatively unknown. In the present study, we evaluated the effects of TA on an acetaminophen (APAP)-induced hepatotoxicity model, which was established by administration of 400mg/kg of APAP. The levels of alanine transferase (ALT), aspartate transferase (AST), dendothelin-1 (ET-1), nitric oxide (NO) and malondialdehyde (MDA) in the APAP-induced hepatotoxicity mice were significantly increased (up to ~200%), while their levels were reduced by pretreatment with TA (25 and 50mg/kg) (P<0.05). The activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) in the APAP-induced hepatotoxicity mice were significantly reduced (lower to ~65%), while their activities were increased by pretreatment with TA (25 and 50mg/kg) (P<0.05). In addition, pretreatment with oral TA (25 and 50mg/kg) for 3days before the APAP administration dose-dependently ameliorated changes in hepatic histopathology, suppressed overexpression of interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), c-fos, c-jun, NF-κB (p65) and caspase-3 (all P<0.05), downregulated bax and upregulated bcl-2, nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) (all P<0.05) in the liver. These results indicate that TA exhibits significant hepatoprotective effects against APAP-induced hepatotoxicity and suggest that the hepatoprotective mechanisms of TA may be related to anti-oxidation, anti-inflammation and anti-apoptosis.



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Injured Brains and Adaptive Networks: The Benefits and Costs of Hyperconnectivity

Publication date: Available online 1 April 2017
Source:Trends in Cognitive Sciences
Author(s): Frank G. Hillary, Jordan H. Grafman
A common finding in human functional brain-imaging studies is that damage to neural systems paradoxically results in enhanced functional connectivity between network regions, a phenomenon commonly referred to as 'hyperconnectivity'. Here, we describe the various ways that hyperconnectivity operates to benefit a neural network following injury while simultaneously negotiating the trade-off between metabolic cost and communication efficiency. Hyperconnectivity may be optimally expressed by increasing connections through the most central and metabolically efficient regions (i.e., hubs). While adaptive in the short term, we propose that chronic hyperconnectivity may leave network hubs vulnerable to secondary pathological processes over the life span due to chronically elevated metabolic stress. We conclude by offering novel, testable hypotheses for advancing our understanding of the role of hyperconnectivity in systems-level brain plasticity in neurological disorders.



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1/(2+Rc): A simple predictive formula for laboratory shrinkage-stress measurement

Publication date: Available online 1 April 2017
Source:Dental Materials
Author(s): Wondwosen A. Aregawi, Alex S.L. Fok
ObjectiveThis paper presents and verifies a simple predictive formula for laboratory shrinkage-stress measurement in dental composites that can account for the combined effect of material properties, sample geometry and instrument compliance.MethodsA mathematical model for laboratory shrinkage-stress measurement that includes the composite's elastic modulus, shrinkage strain, and their interaction with the sample's dimensions and the instrument's compliance has previously been developed. The model contains a dimensionless parameter, Rc, which represents the compliance of the instrument relative to that of the cured composite sample. A simplified formula, 1/(2+Rc), is proposed here for the normalized shrinkage stress to approximate the original model. The accuracy of the simplified formula is examined by comparing its shrinkage-stress predictions with those given by the exact formula for different cases. These include shrinkage stress measured using instruments with different compliances, samples with different thicknesses and composites with different filler fractions.ResultsThe simplified formula produces shrinkage-stress predictions that are very similar to those given by the full formula. In addition, it correctly predicts the decrease in shrinkage stress with an increasing configuration factor for compliant instruments. It also correctly predicts the value of the so-called flow factor of composites despite the fact that creep is not considered in the model.SignificanceThe new simple formula significantly simplifies the prediction of shrinkage stress for disc specimens used in laboratory experiments without much loss in precision. Its explicit analytical form shows clearly all the important parameters that control the level of shrinkage stress in such measurements. It also helps to resolve much of the confusion caused by the seemingly contradictory results reported in the literature. Further, the formula can be used as a guide for the design of dental composite materials or restorations to minimize their shrinkage stress.



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Lexical influence on stress processing in a fixed-stress language

Publication date: Available online 2 April 2017
Source:International Journal of Psychophysiology
Author(s): Linda Garami, Anett Ragó, Ferenc Honbolygó, Valéria Csépe
In the present study, we investigate how lexicality affects the processing of suprasegmental features at the word level. In contrast to earlier studies which analyzed the role of either segmental or suprasegmental feature in language processing our aim was to investigate the effect of the lexical status on the processing of violated stress pattern defined by linguistic rules. We have conducted a passive oddball ERP experiment, presenting a frequent CVCV word with legal (familiar) and illegal (unfamiliar) stress patterns. Former results obtained with pseudo-words in a similar paradigm enabled to assess the influence of lexical information on stress processing.The presence of lexically relevant information resulted in different ERP patterns compared to those obtained with pseudo-words. We obtained two consecutive MMN responses to the illegally stressed words while violating the illegal stress pattern with a legal one the deviant stimulus elicited two consecutive MMN responses as well. In the latter condition lexicality clearly enhanced the comparison of prosodic information between standard and deviant stimuli, as these components very completely missing when presenting pseudo-words.We interpret the results that lexicality acts as a filter since in the absence of lexical familiarity unfamiliar stress patterns are discriminated better.Our results highlight that even when stress is fully predictable, it is taken into account during pre-attentive processing of linguistic input.



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Diversity in AMPAR complexes in the brain

Publication date: August 2017
Source:Current Opinion in Neurobiology, Volume 45
Author(s): Eric Jacobi, Jakob von Engelhardt
AMPA receptor (AMPAR) complexes comprise four of the AMPAR subunits GluA1-4 and several additional interacting proteins. Subunit composition determines AMPAR function. However, AMPAR function depends to a large extent also on interacting proteins, which influence trafficking to the cell surface, activity-dependent subcellular localization and gating of AMPARs. In this review we report about recent findings on the diversity of AMPAR complexes that allow us to better understand functional properties of native receptors in the brain.



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Risk factors and state-of-the-art indications for boost irradiation in invasive breast carcinoma

Publication date: Available online 1 April 2017
Source:Brachytherapy
Author(s): Alfredo Polo, Csaba Polgár, Jean-Michel Hannoun-Levi, Jose-Luis Guinot, Cristina Gutierrez, Razvan Galalae, Erik van Limbergen, Vratislav Strnad
PurposeThe aim of the study was to give recommendations on patient selection criteria for the administration of boost doses after whole-breast irradiation (WBI) in invasive breast cancer based on available clinical evidence complemented by expert opinion.Methods and MaterialsA systematic search of the PubMed database was conducted to identify factors associated with increased risk for local failure that can define risk groups, and to provide evidence for an adequate guidance to the use of the boost as a function of the risk of local recurrence in breast-conserving therapy. The authors reviewed the published clinical evidence for the use of boost after WBI, complemented by other relevant studies and, through a series of formal meetings communications, formulated the recommendations presented in this article.ResultsThe GEC-ESTRO Breast Cancer Working Group recommends three categories guiding patient selection for the use of a boost after WBI: (1) a low-risk group for whom boost adds little benefit, including patients aging at least 50 years with unicentric, unifocal, and clear surgical margins of at least 2 mm and no axillary lymph nodes invasion. In this group, a boost of 10–16 Gy EQD2 after WBI (25fr × 2 Gy or 15 fr × 2.67 Gy) is optional and not mandatory, (2) a high-risk group, for whom boost is considered mandatory and where dose escalation above 16 Gy EQD2 should be considered; including patients aging ≤40 years with close margins, extensive intraductal component or triple-negative phenotype, or patients with positive resection margins regardless of patient age, and (3) an intermediate-risk group, for whom the boost (10–16 Gy EQD2) is considered mandatory, includes patients below 40 years without major risk criteria, patients >40 years and <50 years regardless of any risk factors, or patients >50 years with any risk factor (close margins, tumor size >3 cm, extensive intraductal component, lymphovascular invasion, lymph node invasion, multicentric or multifocal tumors, triple-negative phenotype, or after neoadjuvant chemotherapy in case of residual tumor).ConclusionsThese recommendations may provide a clinical guidance regarding the use of boost after WBI in invasive breast cancer and holds for standard and hypofractionated WBI. Furthermore they should promote further clinical research focusing on controversial issues in the treatment of early-stage breast carcinoma.



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Temporal changes in radiocesium contamination derived from the Fukushima Dai-ichi Nuclear Power Plant accident in oceanic zooplankton in the western North Pacific

Publication date: June 2017
Source:Journal of Environmental Radioactivity, Volume 172
Author(s): Minoru Kitamura, Makio C. Honda, Yasunori Hamajima, Yuichiro Kumamoto, Michio Aoyama, Hajime Kawakami, Tatsuo Aono, Miho Fukuda, Yoshihisa Mino
We investigated temporal changes of the contamination of oceanic zooplankton with radiocesium (¹³⁴Cs and ¹³⁷Cs) derived from the Fukushima Dai-ichi Nuclear Power Plant accident one month to three years after the accident at subarctic and subtropical stations (1900 and 900–1000 km from the plant, respectively) in the western North Pacific. The maximum activity concentrations of ¹³⁷Cs in zooplankton were two orders of magnitude higher than the pre-accident level. In the first four months after the accident, the activity concentrations of radiocesium in subtropical zooplankton decreased rapidly, but no similar change was observed at the subarctic station. The radiocesium derived from atmospheric deposition rapidly decreased as a result of seawater mixing. Thus, most of the subtropical zooplankton (with short lifespans) that had taken up radiocesium just after the accident were probably replaced by newly hatched zooplankton within four months of the accident, whereas subarctic zooplankton (with long lifespans) that were highly contaminated with radiocesium were still alive four months after the accident. By the end of the study, ¹³⁷Cs activity concentrations in subtropical zooplankton were still high, whereas the activity concentrations in subarctic zooplankton had decreased to nearly the pre-accident level. The former concentrations were probably influenced by a secondary supply of radiocesium via advection of subtropical mode water that was highly contaminated with Fukushima-derived radiocesium. Unexpectedly, at the subarctic station, the radiocesium activity concentrations in surface zooplankton were lower than those in subsurface zooplankton, whereas the opposite relationship was observed in surface and subsurface seawater. Because carnivores predominated in the subsurface zooplankton community, we hypothesize that the higher radiocesium activity concentrations in subsurface zooplankton were influenced by bioaccumulation. We conclude that radiocesium activity concentrations in zooplankton are influenced not only by the supply of radiocesium to the environment but also by the characteristics of the zooplankton community.



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Editorial Board

Publication date: May 2017
Source:Brain and Development, Volume 39, Issue 5





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Treatment of intractable seizure in Wolf–Hirschhorn syndrome with bromide

Publication date: Available online 1 April 2017
Source:Brain and Development
Author(s): Inn-Chi Lee, Syuan-Yu Hong




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Announcements and reports

Publication date: May 2017
Source:Brain and Development, Volume 39, Issue 5





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Cover

Publication date: May 2017
Source:Brain and Development, Volume 39, Issue 5





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Contents

Publication date: May 2017
Source:Brain and Development, Volume 39, Issue 5





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Developmental changes in autonomic responses are associated with future reward/punishment expectations: A study of sympathetic skin responses in the Markov decision task

Publication date: Available online 1 April 2017
Source:Brain and Development
Author(s): Hiromi Hosaka, Kakuro Aoyagi, Yoshimi Kaga, Hideaki Kanemura, Kanji Sugita, Masao Aihara
ObjectiveAutonomic nervous system activity is recognized as a major component of emotional responses. Future reward/punishment expectations depend upon the process of decision making in the frontal lobe, which is considered to play an important role in executive function. The aim of this study was to investigate the relationship between autonomic responses and decision making during reinforcement tasks using sympathetic skin responses (SSR).MethodsNine adult and 9 juvenile (mean age, 10.2years) volunteers were enrolled in this study. SSRs were measured during the Markov decision task (MDT), which is a reinforcement task. In this task, subjects must endure a small immediate loss to ultimately get a large reward. The subjects had to undergo three sets of tests and their scores in these tests were assessed and evaluated.ResultsAll adults showed gradually increasing scores for the MDT from the first to third set. As the trial progressed from the first to second set in adults, SSR appearance ratios remarkably increased for both punishment and reward expectations. In comparison with adults, children showed decreasing scores from the first to second set. There were no significant inter-target differences in the SSR appearance ratio in the first and second set in children. In the third set, the SSR appearance ratio for reward expectations was higher than that in the neutral condition.ConclusionsIn reinforcement tasks, such as MDT, autonomic responses play an important role in decision making. We assume that SSRs are elicited during efficient decision making tasks associated with future reward/punishment expectations, which demonstrates the importance of autonomic function. In contrast, in children around the age of 10years, the autonomic system does not react as an organized response specific to reward/punishment expectations. This suggests the immaturity of the future reward/punishment expectations process in children.



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Golgi trafficking defects in postnatal microcephaly: The evidence for “Golgipathies”

Publication date: Available online 2 April 2017
Source:Progress in Neurobiology
Author(s): Sandrine Passemard, Franck Perez, Emilie Colin-Lemesre, Sowmyalakshmi Rasika, Pierre Gressens, Vincent El Ghouzzi
The Golgi apparatus plays a central role in cell homeostasis, not only in processing and maturing newly synthesized proteins and lipids but also in orchestrating their sorting, packing, routing and recycling on the way to their final destination. These multiple secretory pathways require a complex ballet of vesicular and tubular carriers that continuously bud off from donor membranes and fuse to acceptor membranes. Membrane trafficking is particularly prominent in axons, where cargo molecules have a long way to travel before they reach the synapse, and in oligodendrocytes, which require an immense increase in membrane surface in order to sheathe axons in myelin. Interestingly, in recent years, genes encoding Golgi-associated proteins with a role in membrane trafficking have been found to be defective in an increasing number of inherited disorders whose clinical manifestations include postnatal-onset microcephaly (POM), white matter defects and intellectual disability. Several of these genes encode RAB GTPases, RAB-effectors or RAB-regulating proteins, linking POM and intellectual disability to RAB-dependent Golgi trafficking pathways and suggesting that their regulation is critical to postnatal brain maturation and function. Here, we review the key roles of the Golgi apparatus in post-mitotic neurons and the oligodendrocytes that myelinate them, and provide an overview of these Golgi-associated POM-causing genes, their function in Golgi organization and trafficking and the likely mechanisms that may link dysfunctions in RAB-dependent regulatory pathways with POM.



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Identification of transcription factors that may reprogram lung adenocarcinoma

Publication date: Available online 1 April 2017
Source:Artificial Intelligence in Medicine
Author(s): Chenglin Liu, Yu-Hang Zhang, Tao Huang, Yudong Cai
BackgroundLung adenocarcinoma is one of most threatening disease to human health. Although many efforts have been devoted to its genetic study, few researches have been focused on the transcription factors which regulate tumor initiation and progression by affecting multiple downstream gene transcription. It is proved that proper transcription factors may mediate the direct reprogramming of cancer cells, and reverse the tumorigenesis on the epigenetic and transcription levels.MethodsIn this paper, a computational method is proposed to identify the core transcription factors that can regulate as many as possible lung adenocarcinoma associated genes with as little as possible redundancy. A greedy strategy is applied to find the smallest collection of transcription factors that can cover the differentially expressed genes by its downstream targets. The optimal subset which is mostly enriched in the differentially expressed genes is then selected.ResultsSeven core transcription factors (MCM4, VWF, ECT2, RBMS3, LIMCH1, MYBL2 and FBXL7) are detected, and have been reported to contribute to tumorigenesis of lung adenocarcinoma. The identification of the transcription factors provides a new insight into its oncogenic role in tumor initiation and progression, and benefits the discovery of functional core set that may reverse malignant transformation and reprogram cancer cells.



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Subclinical developmental dysplasia of the hip could predispose to femoroacetabular impingement

Publication date: May 2017
Source:Medical Hypotheses, Volume 102
Author(s): Simon Erridge, En Lin Goh, Swathikan Chidambaram
Developmental dysplasia of the hip (DDH) and femoroacetabular impingement (FAI) are separate causes of premature osteoarthritis. There is a paucity of literature describing potential ways in which an individual can be predisposed to FAI. This hypothesis aims to outline how subclinical DDH may predispose a patient to FAI.In DDH the acetabular malformation of the hip joint alters the weight distribution superiorly in the loading axis. In accordance with Wolff's Law, we propose that this change in loading may result in the formation of protrusions on either the acetabular rim or femoral head and neck, predisposing to impingement of the hip during to certain movements and consequently, FAI.Should this hypothesis be proven it would help to reduce the incidence FAI by aiding the understanding of disease aetiology.



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Scholar : Aging, Neuropsychology, and Cognition, Volume 24, Issue 3, May 2017 is now available online on Taylor & Francis Online

The online platform for Taylor & Francis Online content Aging, Neuropsychology, and Cognition, Volume 24, Issue 3, May 2017 is now available online on Taylor & Francis Online. This new issue contains the following articles: Original Articles Sex and post-menopause hormone therapy effects on hippocampal volume and verbal memory B. Blair Braden, Kara B. Dassel, Heather A. Bimonte-Nelson, Holly P. O'Rourke, Donald J. Connor, Sallie Moorhous, Marwan N. Sabbagh, Richard J. Caselli & Leslie C. Baxter Pages: 227-246 | DOI: 10.1080/13825585.2016.1182962 Similarity among tasks is the key to show generalization of cognitive training effects in Alzheimer's disease: a case study Marco Cavallo & Chiara Angilletta Pages: 247-255 | DOI: 10.1080/13825585.2016.1184611 Effects of body mass index and education on verbal and nonverbal memory Liselotte De Wit, Joshua W. Kirton, Deirdre M. O'Shea, Sarah M. Szymkowicz, Molly E. McLaren & Vonetta M. Dotson Pages: 256-263 | DOI: 10.1080/13825585.2016.1194366 How age affects memory task performance in clinically normal hearing persons Charlotte Vercammen, Tine Goossens, Jan Wouters & Astrid van Wieringen Pages: 264-280 | DOI: 10.1080/13825585.2016.1200005 Working memory in healthy aging and in Parkinson's disease: evidence of interference effects Elisa Di Rosa, Doris Pischedda, Paolo Cherubini, Daniela Mapelli, Stefano Tamburin & Michele Burigo Pages: 281-298 | DOI: 10.1080/13825585.2016.1202188 The effects of aging on the working memory processes of multimodal information Elena Solesio-Jofre, José María López-Frutos, Nathan Cashdollar, Sara Aurtenetxe, Ignacio de Ramón & Fernando Maestú Pages: 299-320 | DOI: 10.1080/13825585.2016.1207749 Grit in adolescence is protective of late-life cognition: non-cognitive factors and cognitive reserve Emma Rhodes, Kathryn N. Devlin, Laurence Steinberg & Tania Giovannetti Pages: 321-332 | DOI: 10.1080/13825585.2016.1210079 Age-related cognitive decline as a function of daytime testing Andrei Alexandru Puiu Pages: 333-344 | DOI: 10.1080/13825585.2016.1210080 Free access to Top 20 articles from Advances in School Mental Health Promotion To update which email alerts you receive, manage your alerts within the My Account area. You can also unsubscribe from this alert with one click. If you need any further help, please contact us at support@tandfonline.com Please do not reply to this email. To ensure that you receive your alerts and information from Taylor & Francis Online, please add "alerts@tandfonline.com" and "info@tandfonline.com" to your safe senders list. Taylor & Francis, an Informa business. Taylor & Francis is a trading name of Informa UK Limited, registered in England under no. 1072954. Registered office: 5 Howick Place, London, SW1P 1WG.

Scholar : These new articles for Addiction Research & Theory are available online

The online platform for Taylor & Francis Online content New for Addiction Research & Theory and online now on Taylor & Francis Online: Review Article Harm reduction in gambling: a systematic review of industry strategies Jessica Tanner, Alexandra S. Drawson, Christopher J. Mushquash, Aislin R. Mushquash & Dwight Mazmanian Pages: 1-10 | DOI: 10.1080/16066359.2017.1310204 The Opiate Epidemic. Click here for the Free Access Article Collection: http://ift.tt/2cHzs7g. To update which email alerts you receive, manage your alerts within the My Account area. You can also unsubscribe from this alert with one click. If you need any further help, please contact us at support@tandfonline.com Please do not reply to this email. To ensure that you receive your alerts and information from Taylor & Francis Online, please add "alerts@tandfonline.com" and "info@tandfonline.com" to your safe senders list. Taylor & Francis, an Informa business. Taylor & Francis is a trading name of Informa UK Limited, registered in England under no. 1072954. Registered office: 5 Howick Place, London, SW1P 1WG.

Scholar : These new articles for Acta Oncologica are available online

The online platform for Taylor & Francis Online content New for Acta Oncologica and online now on Taylor & Francis Online: ORIGINAL ARTICLE Increasing incidence and survival in oral cancer: a nationwide Danish study from 1980 to 2014 Kirstine Kim Schmidt Karnov, Christian Grønhøj, David Hebbelstrup Jensen, Irene Wessel, Birgitte Wittenborg Charabi, Lena Specht, Andreas Kjaer & Christian von Buchwald Pages: 1-6 | DOI: 10.1080/0284186X.2017.1307516 Late radiation-induced bowel syndromes, tobacco smoking, age at treatment and time since treatment – gynecological cancer survivors Gunnar Steineck, Fei Sjöberg, Viktor Skokic, Cecilia Bull, Ulrica Wilderäng, Eleftheria Alevronta, Gail Dunberger, Karin Bergmark & Rebecka Jörnsten Pages: 1-10 | DOI: 10.1080/0284186X.2017.1307519 Occupational Therapy Free Access Article Collection – click here. To update which email alerts you receive, manage your alerts within the My Account area. You can also unsubscribe from this alert with one click. If you need any further help, please contact us at support@tandfonline.com Please do not reply to this email. To ensure that you receive your alerts and information from Taylor & Francis Online, please add "alerts@tandfonline.com" and "info@tandfonline.com" to your safe senders list. Taylor & Francis, an Informa business. Taylor & Francis is a trading name of Informa UK Limited, registered in England under no. 1072954. Registered office: 5 Howick Place, London, SW1P 1WG.

Scholar : These new articles for Annals of Leisure Research are available online

The online platform for Taylor & Francis Online content New for Annals of Leisure Research and online now on Taylor & Francis Online: Original Articles Leisure as a human right: an exploration of people with disabilities' perceptions of leisure, arts and recreation participation through Australian Community Access Services Ted Evans, Michelle Bellon & Brian Matthews Pages: 1-18 | DOI: 10.1080/11745398.2017.1307120 Work, retirement and working out: the construction of exercise and the social world of retired women Kenneth E. Mobily, Alexa K. Smith & Kristen Chmielewski Pages: 1-22 | DOI: 10.1080/11745398.2017.1309983 The Opiate Epidemic Click here for the Free Access Article Collection. To update which email alerts you receive, manage your alerts within the My Account area. You can also unsubscribe from this alert with one click. If you need any further help, please contact us at support@tandfonline.com Please do not reply to this email. To ensure that you receive your alerts and information from Taylor & Francis Online, please add "alerts@tandfonline.com" and "info@tandfonline.com" to your safe senders list. Taylor & Francis, an Informa business. Taylor & Francis is a trading name of Informa UK Limited, registered in England under no. 1072954. Registered office: 5 Howick Place, London, SW1P 1WG.

Scholar : These new articles for Archives of Agronomy and Soil Science are available online

The online platform for Taylor & Francis Online content New for Archives of Agronomy and Soil Science and online now on Taylor & Francis Online: Original Articles Elevated carbon dioxide level along with phosphorus application and cyanobacterial inoculation enhances nitrogen fixation and uptake in cowpea crop Sumit Kumar Dey, Bidisha Chakrabarti, Radha Prasanna, Devesh Pratap, Shiv Dhar Singh, Tapan Jyoti Purakayastha & Himanshu Pathak This is the author accepted version which has not been proofed or edited To update which email alerts you receive, manage your alerts within the My Account area. You can also unsubscribe from this alert with one click. If you need any further help, please contact us at support@tandfonline.com Please do not reply to this email. To ensure that you receive your alerts and information from Taylor & Francis Online, please add "alerts@tandfonline.com" and "info@tandfonline.com" to your safe senders list. Taylor & Francis, an Informa business. Taylor & Francis is a trading name of Informa UK Limited, registered in England under no. 1072954. Registered office: 5 Howick Place, London, SW1P 1WG.

Oxidative potential of gas phase combustion emissions - An underestimated and potentially harmful component of air pollution from combustion processes

Publication date: June 2017
Source:Atmospheric Environment, Volume 158
Author(s): S. Stevanovic, A. Vaughan, F. Hedayat, F. Salimi, M.M. Rahman, A. Zare, R.A. Brown, R.J. Brown, H. Wang, Z. Zhang, X. Wang, S.E. Bottle, I.A. Yang, Z.D. Ristovski
The oxidative potential (OP) of the gas phase is an important and neglected aspect of environmental toxicity. Whilst prolonged exposure to particulate matter (PM) associated reactive oxygen species (ROS) have been shown to lead to negative health effects, the potential for compounds in gas phase to cause similar effects is yet to be understood.In this study we describe: the significance of the gas phase OP generated through vehicle emissions; discuss the origin and evolution of species contributing to measured OP; and report on the impact of gas phase OP on human lung cells. The model aerosol for this study was exhaust emitted from a Euro III Common-rail diesel engine fuelled with different blends of diesel and biodiesel. The gas phase of these emissions was found to be potentially as hazardous as the particle phase. Fuel oxygen content was found to negatively correlate with the gas phase OP, and positively correlate with particle phase OP. This signifies a complex interaction between reactive species present in gas and particle phase. Furthermore, this interaction has an overarching effect on the OP of both particle and gas phase, and therefore the toxicity of combustion emissions.



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Variations in the APOE allele or BDNF Val66Met polymorphism are not associated with changes in cognitive function following a tertiary education intervention in older adults: The Tasmanian Healthy Brain Project

Publication date: Available online 2 April 2017
Source:Neurobiology of Aging
Author(s): Megan E. Thow, Mathew J. Summers, Jeffery J. Summers, Nichole L. Saunders, James C. Vickers
The APOE ɛ4 allele and the Met variant of the BDNF Val66Met polymorphism are associated with reduced cognitive function in older adults. The aim of this study was to examine the independent and interactional effect of the APOE ɛ4 allele and BDNF Val66Met polymorphism on cognitive function in a cohort of healthy older adults who had undertaken further university level education. Multiple group Latent Growth Curve Modelling revealed no change in cognitive function over time in APOE ɛ4-carriers or in BDNF Met-carriers, nor in carriers of both APOE-ɛ4 and BDNF-Met alleles. Further, the results indicate that allelic variation in either APOE or BDNF does not modify the beneficial effects of a university based education intervention on cognitive function over a four-year period following the intervention.



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On-demand dissolution of modular, synthetic extracellular matrix reveals local epithelial-stromal communication networks

Publication date: June 2017
Source:Biomaterials, Volume 130
Author(s): Jorge Valdez, Christi D. Cook, Caroline Chopko Ahrens, Alex J. Wang, Alexander Brown, Manu Kumar, Linda Stockdale, Daniel Rothenberg, Kasper Renggli, Elizabeth Gordon, Douglas Lauffenburger, Forest White, Linda Griffith
Methods to parse paracrine epithelial-stromal communication networks are a vital need in drug development, as disruption of these networks underlies diseases ranging from cancer to endometriosis. Here, we describe a modular, synthetic, and dissolvable extracellular matrix (MSD-ECM) hydrogel that fosters functional 3D epithelial-stromal co-culture, and that can be dissolved on-demand to recover cells and paracrine signaling proteins intact for subsequent analysis. Specifically, synthetic polymer hydrogels, modified with cell-interacting adhesion motifs and crosslinked with peptides that include a substrate for cell-mediated proteolytic remodeling, can be rapidly dissolved by an engineered version of the microbial transpeptidase Sortase A (SrtA) if the crosslinking peptide includes a SrtA substrate motif and a soluble second substrate. SrtA-mediated dissolution affected only 1 of 31 cytokines and growth factors assayed, whereas standard protease degradation methods destroyed about half of these same molecules. Using co-encapsulated endometrial epithelial and stromal cells as one model system, we show that the dynamic cytokine and growth factor response of co-cultures to an inflammatory cue is richer and more nuanced when measured from SrtA-dissolved gel microenvironments than from the culture supernate. This system employs accessible, reproducible reagents and facile protocols; hence, has potential as a tool in identifying and validating therapeutic targets in complex diseases.

Graphical abstract

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Morphology transformation of multicompartment self-assemblies of ABC triblock copolymers

Publication date: 5 May 2017
Source:Polymer, Volume 116
Author(s): Yang Cong, Qi Zhou, Yuan Xu, Jiaojiao Fang, Kaiyun Zhu
Morphology transformations of multicompartment assemblies of polystyrene-polyisoprene-poly(2-vinylpyridine), PS-PI-P2VP, was demonstrated. As the solvent quality is continuously varied the triblock copolymer experiences transformations from core-shell-corona micelles to particles with perforated lamellae, or from multicompartment micelles into PI-perforated PS-P2VP lamellae. Such multicompartment self-assemblies and morphology transformations may find potential applications as vehicles for multi-drugs or other active substances.

Graphical abstract

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Transport behaviour of aromatic solvents through styrene butadiene rubber/poly [methyl methacrylate] (SBR/PMMMA) interpenetrating polymer network (IPN) membranes

Publication date: 5 May 2017
Source:Polymer, Volume 116
Author(s): Jose James, George V. Thomas, K.P. Pramoda, Sabu Thomas
Sequential polymerization technique has been adopted for the synthesis of a series of full and semi interpenetrating polymer network (IPN) membranes based on styrene butadiene rubber (SBR) and poly [methyl methacrylate] (PMMA). IPN morphology has been tuned by varying the blend composition and extent of cross-linking of both the phases. The dispersed and co-continuous morphologies of IPNs were characterised by AFM, SEM and TEM analysis. The transport behaviour of aromatic hydrocarbons through the membranes has been studied in detail by tracing the solvent uptake up to equilibrium. As the PMMA content in the IPN increases to 60 wt %, the solvent uptake value decreases by about 50% which is in tune with the morphological changes of the system where PMMA phase forms a well interconnected network structure with the SBR phase. The network structure has been compared with the Phantom and the Affine models and also with the theoretical predictions.

Graphical abstract

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Anchor peptides: A green and versatile method for polypropylene functionalization

Publication date: 5 May 2017
Source:Polymer, Volume 116
Author(s): Kristin Rübsam, Benjamin Stomps, Alexander Böker, Felix Jakob, Ulrich Schwaneberg
Polypropylene is one of the widest spread commodity polymers in plastic industry with an estimated global consumption of 62.4 million tons in 2020. Surface modification of polypropylene is required for its application as textile fibers, packaging material or filtration membranes. Modification of polypropylene is challenging due to absent functional surface groups. An anchor-peptide-based toolbox for green and versatile polypropylene functionalization was developed. Fusion proteins composed of enhanced green fluorescent protein (EGFP) and anchor peptides (e.g. cecropin A or LCI) were designed and applied to polypropylene surfaces. Resulting protein coatings of EGFP-LCI were characterized by fluorescence and scanning force microscopy. The fusion protein EGFP-LCI formed densely packed monolayers of 4.1 ± 0.2 nm thickness. A microtiter plate-based fluorescence assay was developed to analyze the coating in presence of surfactants. Washing of EGFP-LCI coated polypropylene with 10 mM non-ionic surfactant (Triton X-100) did not detach the protein film, whereas EGFP was removed completely. Anchor peptides promote binding to polypropylene by simple dip-coating at room temperature in water. The high coating density (0.8 pmol/cm²) as well as the number and diversity of provided functional groups offer a viable alternative to conventional modification strategies of functionalizing polypropylene. LCI's role as broadly applicable adhesion promoter was demonstrated by equipping polypropylene with the fluorescent dye ThioGlo-1 via the anchor peptide LCI.

Graphical abstract

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Strain-dependent vibrational spectra and elastic modulus of poly(p-phenylene terephtalamide) from first-principles calculations

Publication date: 5 May 2017
Source:Polymer, Volume 116
Author(s): Lorenzo Avanzini, Luigi Brambilla, Claudia Marano, Alberto Milani
A periodic Density Functional Theory investigation of the structural and spectroscopic properties of poly(p-phenylene terephthalamide) (PPTA), carried out by means of CRYSTAL14, is here reported, for both the three-dimensional crystal and the isolated polymer chain treated as a infinite one-dimensional crystal focusing in particular on strain-dependent Raman spectra. Parallel to the theoretical investigation, spectroscopic measurements have been carried out on undeformed samples and during mechanical testing. In addition to the detailed assignment of the vibrational spectra, polarized IR spectra are also computed and compared to the experimental ones, giving information for the characterization of the orientation properties of PPTA. Finally, the elastic modulus of PPTA is computed for the ideal crystal and the infinite chain and compared to the experimental values reported in the literature. This work shows how a combined experimental/computational approach can give an accurate interpretion of the structural evolution and vibrational spectra of PPTA under strain, providing an effective method to rationalize structure/properties correlations on the basis of the peculiar intra and intermolecular interactions taking place in the fiber.

Graphical abstract

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Effects of precursor topology on polymer networks simulated with molecular dynamics

Publication date: 5 May 2017
Source:Polymer, Volume 116
Author(s): Shimiao Zhang, Li Xi
Molecular modeling of crosslinked polymers often follows arbitrary pathways for network generation, with different precursor topology from experimental systems. We use coarse-grained molecular simulation to study the effects of precursor choice on the predicted network structure and properties. Three sets of precursors with different molecular architectures are designed such that they would form identical networks at the limit of perfect conversion. Little difference is observed between the resulting networks in typical properties including the radial distribution function, macroscopic statistics of network connectivity, and glass transition behaviors. However, the stress-strain relationship in tensile deformation clearly depends on the formation pathway when compared at the same crosslinking density. The elastic modulus of the network is found to correlate strongly with the number of elastic strands in the network, except at the highly-crosslinked limit where substantial discrepancy is observed between networks from different precursors. Although these final networks contain a similar average density of structural defects, the choice of precursor has significant impact on their spatial distribution, leading to the precursor dependence of their mechanical properties. Uniform defect distribution and fast defect elimination can be achieved by designing precursor units with a proper stoichiometric ratio of different monomers.

Graphical abstract

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Copolycarbonates of bio-based rigid isosorbide and flexible 1,4-cyclohexanedimethanol: Merits over bisphenol-A based polycarbonates

Publication date: 5 May 2017
Source:Polymer, Volume 116
Author(s): Seul-A Park, Jaehoon Choi, Sungbin Ju, Jonggeon Jegal, Kang Mun Lee, Sung Yeon Hwang, Dongyeop X. Oh, Jeyoung Park
From an industrial/engineering point of view, the greatest demerit of solely isosorbide (ISB)-based polycarbonate is its fragility; this is considerably overcome in this study by using a dual-diol strategy with 1,4-cyclohexanedimethanol (CHDM). A series of copolycarbonates of ISB, a bio-derived diol with a rigid heterocyclic structure, and ductile CHDM monomers with diphenyl carbonate were prepared by transesterification polymerization. The weight-average molecular weight of the polycarbonates gradually decreases as the ratio of ISB increases; however, their Tg and storage modulus increase. The ultimate elongation of the copolycarbonates is enhanced from 4.6 to 20% as the content of CHDM is increased from 30 to 80 mol%. ISB content greater than 50 mol% makes the copolycarbonates strong but brittle, and ISB content less than 50 mol% makes the copolycarbonates ductile but soft. The polycarbonate with 70/30 mol% of ISB/CHDM shows a 1.25-fold higher Young's modulus, 1.05-fold higher ultimate tensile strength, and one-grade higher pencil hardness than the bisphenol-A (BPA)-based polycarbonate. Interestingly, the hydrophilic ISB content does not affect the degree of hydrophilicity of the copolycarbonate samples. Water droplet contact angles are in the range of 81–87°, comparable to that of the BPA-based polycarbonate.

Graphical abstract

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Nucleation efficiency of fillers in polymer crystallization studied by fast scanning calorimetry: Carbon nanotubes in polypropylene

Publication date: 5 May 2017
Source:Polymer, Volume 116
Author(s): Jürgen E.K. Schawe, Petra Pötschke, Ingo Alig
The influence of multi-walled carbon nanotubes (0–5 wt%) on the crystallization process in isotactic polypropylene has been investigated by DSC and fast scanning calorimetry. In the non-isothermal experiments the crystallization temperature shifts to higher temperatures with increasing nanotube content, αCNT, whereas the polymer crystallinity was not significantly influenced. The critical cooling rate, βc, at which the PP does not crystallize, increases with increasing of αCNT. From βc and αCNT a nucleation efficiency parameter was derived, which is independent of crystallization temperature and filler content. Isothermal crystallization experiments allow differentiating between α-phase and mesophase crystallization. Nanotubes accelerate only the α-phase formation. To describe the efficiency of a nucleation agent an acceleration factor, ε, was introduced, which is the ratio of the characteristic crystallization time of unfilled and filled polymer. For the α-phase formation the acceleration factor ε is related to the number of nuclei per nanotube and the specific effect of the filler on the growth rate.

Graphical abstract

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Synthesis of poly(ethylene glycol) di-itaconate and investigation of its influence on acrylamide based hydrogels meant for water treatment

Publication date: 5 May 2017
Source:Polymer, Volume 116
Author(s): Ayan Dey, Rabin Bera, Debabrata Chakrabarty
Poly(ethylene glycol) (PEG 1500) is functionalized using itaconic acid by melt esterification reaction to obtain a bi-functional co-monomer crosslinker, Poly(ethylene glycol) di-itaconate. The resulting product has been copolymerized with acrylamide in presence of methylene bis-acrylamide as crosslinker (in varying proportions) so as to prepare hydrogel which is mostly recommended for dye removal from textile effluents. FTIR-ATR, Solid state 13-C NMR and WAXS techniques are used to ensure grafting of the PEG diitaconate on the polyacrylamide backbone. The intermediate products are also characterized using FTIR and ¹H NMR spectroscopy. This study reveals that a significant improvement in gel characteristics particularly in respect of swelling properties may be achieved with the hydrogel having only ester type crosslinks. However this is attained at the cost of yield stress. The ester based gel shows better storage modulus, dye sorption ability and the anti-fungal properties in relation to semi-IPN type gels.

Graphical abstract

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Latent curing of epoxy-thiol thermosets

Publication date: 5 May 2017
Source:Polymer, Volume 116
Author(s): Ali Osman Konuray, Xavier Fernández-Francos, Xavier Ramis
Epoxy-thiol curing is a click reaction which allows quantitative yield of the end products. The base-catalyzed reaction is rapid at low temperatures so it is most often desirable to harness reactivity by using latent catalysts. In this work, we used triazabicyclodecene tetraphenylborate (TBD·HBPh4) as a photobase generator (PB). We activated the PB either thermally or by UV light and monitored reaction kinetics by DSC and FTIR methods. Depending on the catalytic system used, the rate of the thiol-epoxy reaction was ordered as follows: Neat base > UV activated PB > thermally activated PB > uncatalyzed system. A series of isothermal and non-isothermal DSC experiments were run on non-irradiated and irradiated samples in order to study the effect of PB content and UV irradiation duration on PB activation efficiency and latency/storage stability. The data from DSC were analyzed using model-free linear isoconversional methods to estimate kinetic parameters such as activation energies. In addition, the kinetics data for both activation methods were shown to be accurately represented by multi-term Kamal models. The storage stability of the systems were studied at room temperature and was shown to fit well to the predictions of the kinetic model.

Graphical abstract

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Long-term viscoelastic properties of an adhesive and molding compound, characterization and modeling

Publication date: 5 May 2017
Source:Polymer, Volume 116
Author(s): Mohammad Rezai Sangtabi, Mehdi Saeed Kiasat
Experimental characterization and theoretical modeling of the viscoelastic behaviors of two epoxy compounds are aimed in the present work. Through bending and torsion dynamic analysis, long-term master curves are obtained for the materials moduli over more than 30 frequency and time decades, and the relevant shift factor over a wide temperature range. The uniqueness of the shift factor for the independent viscoelastic properties is shown. The behavior of the shift factor is categorized in regions below and above the glass transition temperature and expressed by different models. Substantial time dependency of the long-term relaxation bulk modulus and the Poisson's ratio are obtained through incremental relations using the measured relaxation moduli. The characterized viscoelastic behavior of the molding compound is verified by means of a creep test performed at isothermal and non-isothermal conditions. It is further shown that when the adhesive compound is cured between two members as in practice, very low glass transition temperature and mechanical properties are expected due to the more residual diluent.

Graphical abstract

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Decoupling of ion conductivity from segmental dynamics in oligomeric ethylene oxide functionalized oxanorbornene dicarboximide homopolymers

Publication date: 5 May 2017
Source:Polymer, Volume 116
Author(s): Marisa Adams, Victoria Richmond, Douglas Smith, Yangyang Wang, Fei Fan, Alexei P. Sokolov, Dean A. Waldow
In order to design more effective solid polymer electrolytes, it is important to decouple ion conductivity from polymer segmental motion. To that end, novel polymers based on oxanorbornene dicarboximide monomers with varying lengths of oligomeric ethylene oxide side chains have been synthesized using ring opening metathesis polymerization. These unique polymers have a fairly rigid and bulky backbone and were used to investigate the decoupling of ion motion from polymer segmental dynamics. Ion conductivity was measured using broadband dielectric spectroscopy for varying levels of added lithium salt. The conductivity data demonstrate six to seven orders of separation in timescale of ion conductivity from polymer segmental motion for polymers with shorter ethylene oxide side chains. However, commensurate changes in the glass transition temperatures Tg reduce the effect of decoupling in ion conductivity and lead to lower conductivity at ambient conditions. These results suggest that both an increase in decoupling and a reduction in Tg might be required to develop solid polymer electrolytes with high ion conductivity at room temperature.

Graphical abstract

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Impact of ingredients on the elemental content of baby foods

Publication date: 15 September 2017
Source:Food Chemistry, Volume 231
Author(s): Judith Adikinyi Khamoni, Toby Hamshaw, Philip H.E. Gardiner
The levels of the minerals: Ca, K, Mg, Na, P, and the trace elements: Cd, Cu, Fe, Mn, Ni, Pb, Se, Zn were determined in foods for 4–6, 7+ and 10+ months old babies in a brand available on the UK market. The mineral contents in the vegetarian meals for all the age groups were similar, in contrast, when compared to the non-vegetarian options, the Ca, Na and P levels were higher in the former. Both the trace elements and minerals levels in the 4–6months vegetarian meal were the lowest of all the products analysed. The Cu, Se and Zn levels in all the meals were comparable to those in mature human breast milk. Calculations of the following molar ratios: Zn:Cu, Fe:Zn, and Fe:Mn, pairs of elements that have been shown to interaction antagonistically, were higher in the vegetarian meals.



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