The strength of reward-related learning depends on the degree of activation of ventral tegmental area dopamine neurons

Publication date: 1 August 2018
Source:Behavioural Brain Research, Volume 348
Author(s): E. Galaj, R. Ranaldi
We tested whether (1) the capacity of a reward-associated conditioned stimulus (CS) to cause conditioned activation of ventral tegmental area (VTA) dopamine (DA) neurons is associated with its capacity to elicit conditioned approach responses and (2) whether the acquisition of these capacities by a CS requires N-methyl-D-aspartate (NMDA) and muscarinic acetylcholine (mACh) receptor stimulation. Rats were trained to emit a conditioned approach response to a light CS that was previously paired with food and were treated systemically with scopolamine (a mACh receptor antagonist) or MK-801 (an NMDA receptor antagonist) either prior to each conditioning session (during which animals experienced paired CS and food presentations) or prior to the conditioned approach (CS-only) test. Brains were harvested after the CS-only test and processed for tyrosine hydroxylase (TH) (DA cells) and c-fos in the VTA. When animals received scopolamine or MK-801 treatment prior to conditioning sessions we observed significantly fewer TH-labeled (i.e., DA) cells in the VTA that expressed c-fos and significantly less conditioned approach responding during the CS-only test. Further analysis showed a correlation between the number of VTA DA cells activated and the number of conditioned approach responses. Treatments made prior to the CS-only test did not affect responding. Altogether these results suggest that the degree to which a CS elicits conditioned approach depends partially on the degree to which the CS activates VTA DA cells and that the acquisition of both of these capacities by a CS requires mACh and NMDA receptor stimulation.



https://ift.tt/2qSoDC7

Big Browser Is Watching You1

Publication date: Available online 21 April 2018
Source:Microbes and Infection
Author(s): Sophia Julia Häfner




https://ift.tt/2F4tyFj

Ethnic disparity in breast cancer survival in southern Thai women

Publication date: June 2018
Source:Cancer Epidemiology, Volume 54
Author(s): Shama Virani, Elizabeth C. Wetzel, Suphawat Laohawiriyakamol, Pleumjit Boonyaphiphat, Alan Geater, Celina G. Kleer, Judy Pang, Katie M. Rentschler, Justin A. Colacino, Carlos F. Mendes de Leon, Laura S. Rozek, Hutcha Sriplung
BackgroundBreast cancer has the highest incidence in women of all cancers and its burden is expected to continue to increase worldwide, especially in middle-income countries such as Thailand. The southern region of Thailand is unique in that it is comprised of 30% Muslims, whereas the rest of Thailand is 95% Buddhist. Breast cancer incidence and survival differ between these religious groups, but the association between clinical subtype of breast cancer and survival has not yet been assessed.MethodsHere we characterized differences in breast cancer survival with consideration to clinical subtype by religious group (Muslim Thai and Buddhist Thai women). We compared distributions of age, stage and clinical subtype and assessed overall survival by religion.ResultsOur findings show that Muslim Thai women with breast cancer are diagnosed at a younger age, at later stages and have shorter overall survival times compared to Buddhist Thai women with breast cancer. We also observe a higher proportion of triple negative tumors characterized in Muslim Thai women.ConclusionsOur findings confirm previous studies that have shown lower survival rates in Muslim Thai women compared to Buddhist women with breast cancer and offer novel information on subtype distribution. To date, this is the first study assessing clinical subtypes in southern Thailand by religious status.ImpactOur findings are critical in providing information on the role of clinical subtype in cancer disparities and provide evidence from the Southeast Asian region for global studies on breast cancer survival.



https://ift.tt/2HC67bN

Evaluation of racial disparities in pediatric optic pathway glioma incidence: Results from the Surveillance, Epidemiology, and End Results Program, 2000–2014

Publication date: June 2018
Source:Cancer Epidemiology, Volume 54
Author(s): Erin C. Peckham-Gregory, Roberto E. Montenegro, David A. Stevenson, David H. Viskochil, Michael E. Scheurer, Philip J. Lupo, Joshua D. Schiffman
BackgroundRacial predilection to pediatric cancer exists; however optic pathway glioma (OPG) risk differences by race/ethnicity are undefined. We estimated differences in OPG incidence across racial/ethnic groups in a multi-state cancer surveillance registry in the United States.MethodsOPG data were obtained from the Surveillance, Epidemiology, and End Results (SEER-18) Program, 2000–2014. Race/ethnicity was categorized as: White; Black; Asian; Other; and Latino/a ("Spanish-Hispanic-Latino"). Latino/a included all races, while all other categories excluded those identified as Latino/a. Age-adjusted incidence rates and rate ratios (IRR) with 95% confidence intervals (CIs) were generated in SEER-STAT (v8.3.4).ResultsData on 709 OPG cases ages 0–19 were abstracted from SEER-18. Minority children experienced lower age-adjusted OPG incidence rates compared to White children (IRRBlack = 0.38, 95% CI: 0.28–0.50; IRRAsian = 0.41, 95% CI: 0.29–0.58; and IRRLatino/a = 0.39, 95% CI: 0.32–0.48). In subgroup analyses among the highest risk age categories (0–4, 5–9), minority children experienced lower incidence rates compared to White children. Specific patterns for Latinos/as also emerged. Latino/a children ages 0–4 experienced the lowest incidence rates of all racial/ethnic groups compared to Whites (0.24 per 100,000 person-years versus 0.66 per 100,000 person-years, respectively), whereas among those ages 5–9, Black and Asian children experienced the lowest incidence rates (0.08 per 100,000 person-years each).ConclusionsIncidence of OPGs was highest among White children. This study represents one of the largest to assess differences in OPG susceptibility by race/ethnicity. These findings may inform future studies that seek to evaluate modifying factors for this pediatric tumor including tumorigenesis, treatment, outcome, and long-term late effects.



https://ift.tt/2vybjIG

Bayesian estimates of the incidence of rare cancers in Europe

Publication date: June 2018
Source:Cancer Epidemiology, Volume 54
Author(s): Laura Botta, Riccardo Capocaccia, Annalisa Trama, Christian Herrmann, Diego Salmerón, Roberta De Angelis, Sandra Mallone, Ettore Bidoli, Rafael Marcos-Gragera, Dorota Dudek-Godeau, Gemma Gatta, Ramon Cleries
BackgroundThe RARECAREnet project has updated the estimates of the burden of the 198 rare cancers in each European country. Suspecting that scant data could affect the reliability of statistical analysis, we employed a Bayesian approach to estimate the incidence of these cancers.MethodsWe analyzed about 2,000,000 rare cancers diagnosed in 2000–2007 provided by 83 population-based cancer registries from 27 European countries. We considered European incidence rates (IRs), calculated over all the data available in RARECAREnet, as a valid a priori to merge with country-specific observed data. Therefore we provided (1) Bayesian estimates of IRs and the yearly numbers of cases of rare cancers in each country; (2) the expected time (T) in years needed to observe one new case; and (3) practical criteria to decide when to use the Bayesian approach.ResultsBayesian and classical estimates did not differ much; substantial differences (>10%) ranged from 77 rare cancers in Iceland to 14 in England. The smaller the population the larger the number of rare cancers needing a Bayesian approach. Bayesian estimates were useful for cancers with fewer than 150 observed cases in a country during the study period; this occurred mostly when the population of the country is small.ConclusionFor the first time the Bayesian estimates of IRs and the yearly expected numbers of cases for each rare cancer in each individual European country were calculated. Moreover, the indicator T is useful to convey incidence estimates for exceptionally rare cancers and in small countries; it far exceeds the professional lifespan of a medical doctor.



https://ift.tt/2qNrrS6

Gender influence on the salivary protein profile of finishing pigs

Publication date: 30 April 2018
Source:Journal of Proteomics, Volume 178
Author(s): Ana M. Gutiérrez, Ana Montes, Cándido Gutiérrez-Panizo, Pablo Fuentes, Ernesto De La Cruz-Sánchez
A study on gender differences in the normal range of biomarkers in porcine saliva samples has the scope for further attention. In the present study, the salivary protein profiles of age-matched healthy male and female finishing pigs were compared. The levels of salivary adenosine deaminase (ADA) activity, haptoglobin (Hp) and C-reactive protein (CRP) have been quantified in 32 male and 32 female pigs to ensure the presence of gender effect on the median levels of salivary biomarkers. Moreover, the total salivary protein content was quantified and compared. The overall salivary protein distribution was compared with SDS-PAGE in 14 male and 14 female pigs and the possible gender influence in the salivary protein profile was analysed by 2DE in 6 male and 6 female pigs. Statistically significant differences were observed in the median values of Hp, CRP, and ADA between male and female pigs (p<0.005). Although the total salivary protein content was not different between the sexes, the salivary protein distribution and profile showed specific gender differences in three proteins of the lipocalin family: the odorant-binding protein, salivary lipocalin and lipocalin 1. These proteins have been related to animal immune status and should be further explored as possible porcine salivary biomarkers.SignificanceThe biological relevance of the reported research is based on the possible gender influence on the discovery of salivary biomarkers in porcine production. As differences have been reported in the salivary protein distribution in male pigs in comparison to that of female pigs, the normal-range values, according to gender, of the newly discovered biomarkers should be explored and defined prior to its application in the porcine production system. A hormonal sexual influence is highly hypothesized.

Graphical abstract

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Differences in resistance to nitrogen and phosphorus deficiencies explain male-biased populations of poplar in nutrient-deficient habitats

Publication date: 30 April 2018
Source:Journal of Proteomics, Volume 178
Author(s): Haifeng Song, Yanbao Lei, Sheng Zhang
In most forest soils, the availability of nitrogen (N) and phosphorus (P) nutrients is low and unable to meet the requirement of tree growth. In the past decades, sex-based differences in poplar have been investigated in morphology and physiology. Proteomic techniques provide new insights into sex-specific differences at the molecular level. This review gives a comparative overview of the effects of N and P deficiencies on poplar physiological and proteomic characteristics. Male poplars are more efficient at photosynthesis and nutrient usage than females. Proteins related to carbohydrate metabolism, defence responses and transcription and translation processes are changed to adapt diversely in males and females. These results provide evidence that male poplar have better resistance to nutrient-limiting conditions than females, which may be reasonable for the male-biased sex ratio in nutrient-deficient habitats. Furthermore, this review also discusses the potential growth-defence trade-offs in male and female poplar coping with nutrient limitations.Biological significanceIn the past decades, the physiological and molecular responses of individual trees exposed to nutrient deficiency have been well studied. An important model woody plant, Populus, is dioecious and shows a male-biased sex ratio in nutrient-deficient habitats. Individually, different responses to nutrient limitation between the sexes determine the bias of population sex ratios. Proteomic techniques provide new insights into sex-based differences in the molecular mechanisms underlying nutrient deficiency. This review gives a comparative overview of the identification of nitrogen and phosphorus deficiency effects on physiological and proteomic characteristics. Male poplars are more resistant and have a smaller range of protein changes than females in response to N and P deficiency, which explains the observed male-biased sex ratios to a certain extent. Furthermore, this review also discusses the possible growth-defense trade-offs in male and female poplars coping with nutrient deficiency.

Graphical abstract

https://ift.tt/2HJEyNT

The importance of accounting for sex in the search of proteomic signatures of mycotoxin exposure

Publication date: 30 April 2018
Source:Journal of Proteomics, Volume 178
Author(s): L. Soler, I.P. Oswald
Mycotoxins are natural food and feed contaminants that are toxic to human and animals. Proteomics is an adequate toolbox to investigate the mode of action and the effects of mycotoxins, as these toxicants often alter protein synthesis and degradation, as well as induce changes of important post-translational modifications. For instance, the contaminant deoxynivalenol induces a severe ribosomal stress that affects protein production, whereas the toxin Fumonisin B1 can alter the phosphorylation of a large number of proteins, and patulin is a potent proteotoxic molecule. The response to most mycotoxins is sex-dependent, males being generally more sensitive than females. In addition, for some toxins, the toxic effects observed were different for each sex. Nevertheless, the importance of accounting for a sex-dependent response is often overlooked in toxicology studies involving mycotoxins. Here we review the information that proteomics has provided in pre-clinical studies of mycotoxin exposure as well as the differential response of males and females to these molecules to highlight the need of including male and female individuals when evaluating the impact of mycotoxins in the cell proteome.SignificanceThe current trend in mycotoxicology is the combination of several -omics techniques in order to understand the mechanism of action and effects of these toxic natural food contaminants. One of the goals of these experiments is to determine "potential biomarkers" of mycotoxicoses. Nevertheless, the strategy followed in biomarker research must take into account as many possible factors as possible in order to find robust biomarkers for differential diagnosis. Among the factors that can have an influence in the response to mycotoxins, one of the most important is sex. Traditionally, males are preferentially used in research, as they are more sensitive to mycotoxins and their response is not dependent on hormonal levels, thus less variable. However the intrinsic and hormonal differences between sexes makes that results obtained in males are often not directly transferrable to females. In this review, we want to highlight (1) that proteomics has a great potential on mycotoxin research, and (2) the need in taking into account sex differences in proteomic studies, mostly when the discovery of robust biomarkers of mycotoxins response is desired.

Graphical abstract

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Quantitative proteomics identify an association between extracellular matrix degradation and immunopathology of genotype VII Newcastle disease virus in the spleen in chickens

Publication date: Available online 21 April 2018
Source:Journal of Proteomics
Author(s): Zenglei Hu, Han Gu, Jiao Hu, Shunlin Hu, Xiaoquan Wang, Xiaowen Liu, Xinan Jiao, Xiufan Liu
Pathogenesis of genotype VII Newcastle disease virus (NDV) is characterized with remarkable immunopathology in the spleen in chickens. However, the mechanism for this unique pathological phenotype is not fully understood. Previous transcriptomics data showed that genotype VII NDV JS5/05 caused a greater downregulation of extracellular matrix (ECM) genes than genotype IV virus Herts/33 in the spleen. In this study, the role of ECM in pathology of genotype VII NDV was investigated using quantitative proteomics. Pathology studies showed that JS5/05 caused severe immunopathology characterized with remarkable necrosis in the spleen, whereas Herts/33 only induced mild pathological changes. The ECM was firstly enriched from the spleens and ECM proteins of different categories were identified by LC-MS/MS. Quantitative proteomic analysis showed that JS5/05 caused a significant disruption of ECM integrity and molecular composition compared to Herts/33. Particularly, JS5/05 induced a more remarkable collagen breakdown in the spleen compared to Herts/33. Moreover, matrix metalloproteinase (MMP)-13 and -14 were significantly upregulated by JS5/05 infection. KEGG pathway analysis suggested that differential regulation of ECM proteins by JS5/05 and Herts/33 may impact pathology through different pathways. Therefore, our results suggested that MMP upregulation and consequent ECM degradation contribute to immunopathology of genotype VII NDV in the spleen.SignificancePathogenesis of genotype VII NDV is characterized with severe immunopathology in the spleen in chickens. Elucidating the mechanism of this pathology phenotype is critical to understand pathogenesis of genotype VII NDV. Here, we present the proteomic data of an important non-cellular compartment, the extracellular matrix (ECM), in the spleen from chickens infected with genotype VII and IV NDVs. Our results suggest that significant upregulation of matrix metalloproteinases by genotype VII NDV and consequent disruption of ECM integrity and composition may be associated with immunopathology in the spleen. Moreover, ECM degradation, represented by collagen breakdown, is an important pathology event in the process of genotype VII NDV infection. Our study for the first time presents evidence of ECM regulation by NDV and adds ECM remodeling as a new manifestation for NDV pathology. Our findings also deepen the understanding of NDV pathogenesis.

Graphical abstract

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Editorial Board

Publication date: 30 April 2018
Source:Journal of Proteomics, Volume 178





https://ift.tt/2HQPSVX

Sex differences in murine myocardium are not exclusively regulated by gonadal hormones

Publication date: 30 April 2018
Source:Journal of Proteomics, Volume 178
Author(s): Franz Theuring, Boris Neumann, Christian Scheler, Peter R. Jungblut, Karima Schwab
We investigated sex differences in cardiac protein patterns of intact and castrated mice using proteomics and 1D and 2D immunoblotting. To exclude differences concerning developmental aspects gonadectomy was conducted in mature mice at the age of three months. The main sex-related regulation in the protein pattern of the myocardium occurred for proteins involved in metabolic processes whereas only few proteins involved in other pathways underwent a regulation. Many regulated proteins (2/3) displayed a characteristic V form, which means that these proteins are up- or down-regulated in sexually mature compared to young mice and are back-regulated after castration, emphasizing a direct regulation by gonadal hormones. Several other spots (1/3) showed the same male/female regulation or a drastic increase in male/female spot intensity ratio after castration, suggesting either a regulation independent of sex hormones or a removal of an inhibiting feedback mechanism by gonadectomy. Technically, we found that it cannot be expected that a single spot contains only one protein species and that one protein is present in only one spot. We thus propose for proteomic investigations to identify/quantify all spots of a 2-DE pattern to obtain information about protein speciation and its potential importance for function and pathology.Biological significanceSex related differences in cardiovascular disease, including risk factors, disease manifestation and outcomes, are far from being well understood, and improved biological understanding of these differences in the healthy myocardium is of great importance. We investigated sex related changes of myocardial protein pattern in intact and castrated mice at different ages and found metabolic proteins to be highly regulated, some of which independently from gonadal hormones.

Graphical abstract

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Gender-related increase of tropomyosin-1 abundance in platelets of Alzheimer's disease and mild cognitive impairment patients

Publication date: 30 April 2018
Source:Journal of Proteomics, Volume 178
Author(s): Christina Maria Reumiller, Georg Johannes Schmidt, Ina Dhrami, Ellen Umlauf, Eduard Rappold, Maria Zellner
The incidence of Alzheimer's disease (AD) is higher in elderly women than in men. The molecular background of this gender-related risk, however, is largely unknown. In a previous proteomics study, we identified significantly elevated levels of monoamine oxidase-B and tropomyosin-1 in AD patients, together with significant changes of the genetic AD risk factors apolipoprotein E4 (APOE4) and glutathione S-transferase omega 1 (GSTO1), in platelets - a promising source for AD blood biomarkers. The present study aimed to investigate the gender-specificity as well as the disease-stage dependency of these biomarkers in AD patients and those with mild cognitive impairment (MCI). Tropomyosin-1 and monoamine oxidase-B protein levels were quantified by 2-D DIGE and 1-D Western blotting. Here, for the first time, we revealed a significant increase of 38&39kDa tropomyosin-1 protein levels in female but not male AD (+56%; p=0.008) and MCI patients (+46%; p=0.041) measured by 1-D WB. In contrast, levels of monoamine oxidase-B were, independently of gender, elevated in AD patients (+52%; p=0.009) but unaltered in MCI compared to control subjects. Moreover, we confirmed that APOE4-positive females are at a higher risk (OR=18.7; p=9.7E−09) of developing AD compared to APOE4-positive males (OR=6.5; p=5.9E−04). No gender-related effects were observed for GSTO1.SignificancePlatelet tropomyosin-1 constitutes a gender-related and stage-dependent protein in cognitive impairment. In contrast, platelet monoamine oxidase-B, frequently described to be increased in platelets and brains of AD patients, shows a gender-independent but stage-related increase since it is unaltered in MCI subjects. A blood biomarker test for this preceding stage of AD that considers gender-specificity is not yet available. The newly described AD-related platelet protein profiles might refine and facilitate routine diagnosis and enable early as well as tailored interventions.

Graphical abstract

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Scholar : Chinese Journal of Otorhinolaryngology, Year 2018, Issue 02 -New Issue Alert.

New Issue TOC Alert Dear Valued Customer, We are pleased to deliver your requested table of contents alert for Chinese Journal of Otorhinolaryngology. Year 2018 Issue 02 is now available on CAOD. In this issue: Middle ear teratoma in infant:report of three cases and review of the literatures (婴幼儿中耳畸胎瘤3例临床分析) Peng Zhe, ,Wang Zhenxiao, ,Xie Jing, ,Wang Line, ,Liu Yun, ,Gong Shusheng ...... page:81-85 Analysis of curative effect of transoral radiofrequency ablation microsurgery on glottic carcinoma with anterior commissure involvement at the early stage (经口低温等离子手术治疗侵犯前连合的早期声门型喉癌) Yang Shuzhi, ,Zhou Chengyong, ,Wang Feng, ,Sun Baochun, ,Han Zeli, ,Shen Yao, ,Han Jiahong, ,Zhang Hongjia ...... page:86-91 Planned neck dissection in the treatment of locally advanced head and neck squamous cell carcinoma (计划性颈淋巴清扫术在局部晚期头颈部鳞状细胞癌综合治疗中的应用) Jiang Lin, ,Lou Jianlin, ,Wang Kejing, ,Fang Meiyu, ,Fu Zhenfu ...... page:92-96 Long-term efficacy of supracricoid partial laryngectomy for 298 patients with laryngeal carcinoma (喉癌环状软骨上喉部分切除术298例远期疗效分析) Tao Lei, ,Zhou Liang, ,Wu Haitao, ,Gong Hongli, ,Chen Xiaoling, ,Li Xiaoming, ,Li Cai, ,Zhou Jian ...... page:97-104 Evaluation of central lymph node dissection for papillary thyroid carcinoma in cN0 T1/T2 (cN0 T1/T2期甲状腺乳头状癌行颈中央区淋巴清扫的合理性及其范围的探讨) Zhao Shuyan, ,Ma Yunhai, ,Yin Zhe, ,Zhan Xiangxiang, ,Cheng Ruochuan, ,Qian Jun ...... page:105-109 The experimental study on endoplasmic reticulum stress-participated outer hair cell apoptosis in cadherin 23 gene mutant mice (内质网应激参与钙黏蛋白23基因突变小鼠耳蜗外毛细胞损伤的实验研究) Hu Juan, ,Chen Zichen, ,Zhang Yuzhong, ,Han Peng, ,Ma Weijun, ,Zhang Qing, ,Xu Min ...... page:110-117 Effect of melatonin on expression of Prestin protein in the inner ear of mice following radiotherapy (褪黑素对小鼠放疗后内耳Prestin蛋白表达的影响) Chen Ting, ,Zhang Wei, ,Liang Yong, ,Li Qi, ,Yang Chen, ,Yuan Yixin, ,Ban Molu ...... page:118-123 The effect of miR-497 on laryngeal squamous cell carcinoma invasion through modulating PlexinA4 (miR-497调控PlexinA4对喉鳞状细胞癌侵袭的影响) Niu Juntao, ,Liu Shuguang, ,Huang Yongwang, ,Li Chao ...... page:124-130 Correlation between patulous Eustachian tube with habitual nasal extraction and acquired middle ear cholesteatoma (咽鼓管异常开放伴习惯性抽鼻与后天性中耳胆脂瘤的关系) Fu Tao, ,Zhang Kun, ,Zhang Xiaowen, ,Wang Zhiyuan ...... page:131-133 Study on bone metabolism in postmenopausal women with idiopathic benign paroxysmal positional vertigo (绝经后女性特发性良性阵发性位置性眩晕患者骨代谢的研究) Gu Chengyao, ,Han Weiwei, ,Wu Yunqin, ,Fan Zhenyi, ,Chen Caijing, ,Chen Huimin ...... page:134-137 Chylous leakage attributable to post-operation on piriformis undifferentiated sarcoma combined with squamous cell carcinoma:a case report (梨状窝未分化肉瘤合并鳞状细胞癌术后并发乳糜漏一例) Liao Hongming, ,Liu Yingxin, ,Nan Haijing, ,Jiang Xian ...... page:138-140 IgG4-related sclerosing disease with initial ear symptom: a case report (以耳部病变为首发症状的IgG4相关硬化性疾病一例) Hu Ming, ,Wang Wei, ,Cheng Yan ...... page:140-143 One case of ossifying fibroma of the temporal bone with middle ear cholesteatoma (颞骨骨瘤合并胆脂瘤一例) Zhang Qiuyun, ,Lin Chang ...... page:143-145 Paranasal peripheral primitive neuroectodermal tumor:a case report (鼻旁外周原始神经外胚层肿瘤一例) Zhu Guochen ...... page:145-147 Inflammatory myofibroblastic tumor of thyroid:a case report (甲状腺炎性肌纤维母细胞瘤一例) An Ning, ,Luo Yan, ,Wang Jun, ,Wang Xiaolong, ,Man Guodong, ,Song Yiding ...... page:148-149 Research progress of functional magnetic resonance imaging in mechanism studies of tinnitus (功能性磁共振成像应用于耳鸣机制研究进展) Ji Bobo, ,Li Ming, ,Zhang Jianning ...... page:150-154 Mechanisms underlying glucocorticoid resistance in chronic rhinosinusitis with nasal polyps (慢性鼻-鼻窦炎伴鼻息肉治疗中糖皮质激素抵抗的机制) Zhang Yunyun, ,Lou Hongfei, ,Wang Chengshuo, ,Zhang Luo ...... page:154-160 CAOD TOC Alerts Note Thank you for choosing CAOD Table of Contents (TOC) Alert Service. You are receiving this email because you have requested to receive information from CAOD as a registered user of our Table of Content Alert for journals. To manage your TOC Alerts, please click here. For all enquiries, problems or suggestions regarding this service, please contact info@oriprobe.com. China/Asia on Demand (CAOD) Customer Service

Scholar : West China Journal of Stomatology, Year 2018, Issue 01 -New Issue Alert.

New Issue TOC Alert Dear Valued Customer, We are pleased to deliver your requested table of contents alert for West China Journal of Stomatology. Year 2018 Issue 01 is now available on CAOD. In this issue: Occlusion design of edentulous implant prosthesis (无牙颌种植义齿的咬合设计) Zhang Xueyang, ,Huang Yanhong, ,Chen Pei, ,Jiang Pan, ,Wang Yarong, ,Su Yuan ...... page:1-3 Association between the dental caries and the human leucocyte antigen DQB1 allele polymorphisms among the Uygur and Han children in Xinjiang (新疆维吾尔族和汉族儿童龋病与人类白细胞抗原-DQB1等位基因多态性的相关性研究) Zhang Ruihan, ,Li Xiaobing, ,Wang Liping, ,Liu Yishan ...... page:4-8 Influence of dexamethasone on the cell polarity and PAR complex of the embryonic epithelial cells in the palate (地塞米松对腭胚突上皮细胞PAR复合体和细胞极性的影响) Ma Li, ,Shi Bing, ,Zheng Qian ...... page:9-16 Preparation and characterization of oriented scaffolds derived from cartilage extracellular matrix and silk fibroin (丝素蛋白-软骨脱细胞外基质复合取向支架的制备及评价) Teng Binhong, ,Zhao Yanhong, ,Wang Lianyong, ,Yang Qiang, ,Li Hongfa, ,Li Yunjie ...... page:17-22 Neurotrophin 3 promotes osteogenic differentiation of human dental follicle cells (神经营养素3促进人牙囊细胞成骨分化) Lei Wei, ,Ma Yue, ,Ren Aishu ...... page:23-28 Expression and clinical significance of proline-rich tyrosine kinase 2 and phospho-protein kinase B in tongue squamous cell carcinoma (富含脯氨酸的酪氨酸激酶2和磷酸化的丝氨酸/苏氨酸蛋白激酶在舌鳞状细胞癌组织中的表达及临床意义) Li Lingling, ,Wang Shengzhi, ,Liu Xuyang, ,Liu Hao, ,Gong Zhaohua ...... page:29-32 Experimental study of demineralized dentin matrix on osteoinduction and related cells identification (脱矿牙本质基质骨诱导性及对相关细胞鉴定的实验研究) Yang Shengyin, ,Chen Ping, ,Bao Jibo, ,Ding Yixin, ,Zou Jinyang, ,Xie Zhigang ...... page:33-38 K (lysine) acetyltransferase 2A affects the osteogenic differentiation of periodontal ligament stem cells through the canonical Wnt pathway (赖氨酸乙酰基转移酶2A通过经典Wnt通路影响牙周膜干细胞成骨分化) Guo Wucheng, ,Cheng Jieli, ,Yang Zhengyi, ,Zhang Yi, ,He Enliang, ,Qian Jun, ,Song Jingjing, ,Sun Jin, ,Yuan Lin ...... page:39-45 Antibacterial dental adhesive containing nanoantibacterial inorganic fillers (含纳米抗菌无机填料树脂粘接剂的合成及相关性能研究) Chen Deying, ,Hu Ge, ,Zhou Chuanjian, ,Ge Jianhua, ,Wu Junling ...... page:46-51 Cosmetic technique application on the modification of lip deformity after cleft lip surgery (化妆技术用于唇裂术后患者唇畸形修饰的效果探讨) Chen Lixian, ,Wang Huajun, ,Gong Caixia, ,Zheng Qian, ,Shi Bing, ,Zhang Bihe ...... page:52-55 Reliability study in the measurement of the cusp inclination angle of a chairside digital model (椅旁数字化模型上测量牙尖斜面夹角的可靠性研究) Liu Xinggang, ,Chen Xiaoxian ...... page:56-59 Application of bone-support guide by three-dimensional printing technique in maxillary LeFort Ⅰ osteotomy (骨支持式3D打印导板在上颌骨LeFortⅠ型截骨术中的应用) Qu Zhenyu, ,Wang Qian, ,Zhao Yan, ,Sheng Lanlan, ,Ma Weidong, ,Qu Weiguo ...... page:60-65 Comparative study on the shade matching performance of dental students under D55 and D65 light sources conditions (口腔医学生在D55和D65光源下比色效果的对比研究) Xiong Yiqing, ,Li Gang, ,Lin Yunhong, ,Cao Zhiyun, ,Wei Yanan, ,Li Wei ...... page:66-70 Application of periodontal microsurgery in the augmentation of attached gingiva around an implant (显微牙周外科技术在种植体周附着龈增宽术中的应用) Rong Mingdeng, ,Huang Yanhong, ,Lu Haibin, ,Xu Gelin, ,Li Shaobing, ,Su Yuan, ,Chen Pei, ,Jiang Pan, ,Zhang Xueyang ...... page:71-75 Experimental research on Arginine-gingipain A gene vaccine from Porphyromonas gingivalis that prevents peri-implantitis in Beagle dogs (牙龈卟啉单胞菌精氨酸特异性牙龈素基因疫苗预防比格犬种植体周围炎的实验研究) Li Chuanhua, ,Wang Zhifeng, ,Zhu Lina, ,Fan Xin, ,Lan Jing ...... page:76-81 Disheveled 2 around the implant at an early stage of hyperlipidemic rats (蓬乱蛋白2在高脂血症大鼠种植体周围早期表达的实验研究) Dong Xiaofei, ,Wang Hui, ,Lan Jing ...... page:82-86 Current situation and prospect for orthodontic thermoplastic materials (正畸用热压膜材料现状与展望) Wang Ruyi, ,Zhao Zhihe, ,Li Yu ...... page:87-91 Mechanisms and implications of cancer cell dormancy in head and neck carcinoma (头颈部肿瘤休眠机制的研究进展) Gao Xiaolei, ,Liang Xinhua, ,Tang Yaling ...... page:92-98 Effect of inflammaging on periodontitis (炎性衰老在牙周炎中的作用) Wang Qi, ,Zhou Xinyi, ,Ding Yi ...... page:99-103 Recent achievements in the microbiological etiology of dental caries (龋病微生物因素研究进展) Chen Jing, ,Cheng Lei, ,Zhou Xuedong, ,Peng Xian ...... page:104-108 Treatment of a patient with considerably thin alveolar bone and severe open bite (薄型牙槽骨的重度前牙开(牙合)病例治疗1例) Zhuo Haiya, ,Hu Zhou, ,Zhao Qing ...... page:109-114 hua xi kou qiang yi xue za zhi gao yue (《华西口腔医学杂志》稿约) ...... page:115 CAOD TOC Alerts Note Thank you for choosing CAOD Table of Contents (TOC) Alert Service. You are receiving this email because you have requested to receive information from CAOD as a registered user of our Table of Content Alert for journals. To manage your TOC Alerts, please click here. For all enquiries, problems or suggestions regarding this service, please contact info@oriprobe.com. China/Asia on Demand (CAOD) Customer Service

Scholar : Chinese Journal of Otorhinolaryngology Head and Neck Surgery, Year 2018, Issue 02 -New Issue Alert.

New Issue TOC Alert Dear Valued Customer, We are pleased to deliver your requested table of contents alert for Chinese Journal of Otorhinolaryngology Head and Neck Surgery. Year 2018 Issue 02 is now available on CAOD. In this issue: Middle ear teratoma in infant:report of three cases and review of the literatures (婴幼儿中耳畸胎瘤3例临床分析) Peng Zhe, ,Wang Zhenxiao, ,Xie Jing, ,Wang Line, ,Liu Yun, ,Gong Shusheng ...... page:81-85 Analysis of curative effect of transoral radiofrequency ablation microsurgery on glottic carcinoma with anterior commissure involvement at the early stage (经口低温等离子手术治疗侵犯前连合的早期声门型喉癌) Yang Shuzhi, ,Zhou Chengyong, ,Wang Feng, ,Sun Baochun, ,Han Zeli, ,Shen Yao, ,Han Jiahong, ,Zhang Hongjia ...... page:86-91 Planned neck dissection in the treatment of locally advanced head and neck squamous cell carcinoma (计划性颈淋巴清扫术在局部晚期头颈部鳞状细胞癌综合治疗中的应用) Jiang Lin, ,Lou Jianlin, ,Wang Kejing, ,Fang Meiyu, ,Fu Zhenfu ...... page:92-96 Long-term efficacy of supracricoid partial laryngectomy for 298 patients with laryngeal carcinoma (喉癌环状软骨上喉部分切除术298例远期疗效分析) Tao Lei, ,Zhou Liang, ,Wu Haitao, ,Gong Hongli, ,Chen Xiaoling, ,Li Xiaoming, ,Li Cai, ,Zhou Jian ...... page:97-104 Evaluation of central lymph node dissection for papillary thyroid carcinoma in cN0 T1/T2 (cN0 T1/T2期甲状腺乳头状癌行颈中央区淋巴清扫的合理性及其范围的探讨) Zhao Shuyan, ,Ma Yunhai, ,Yin Zhe, ,Zhan Xiangxiang, ,Cheng Ruochuan, ,Qian Jun ...... page:105-109 The experimental study on endoplasmic reticulum stress-participated outer hair cell apoptosis in cadherin 23 gene mutant mice (内质网应激参与钙黏蛋白23基因突变小鼠耳蜗外毛细胞损伤的实验研究) Hu Juan, ,Chen Zichen, ,Zhang Yuzhong, ,Han Peng, ,Ma Weijun, ,Zhang Qing, ,Xu Min ...... page:110-117 Effect of melatonin on expression of Prestin protein in the inner ear of mice following radiotherapy (褪黑素对小鼠放疗后内耳Prestin蛋白表达的影响) Chen Ting, ,Zhang Wei, ,Liang Yong, ,Li Qi, ,Yang Chen, ,Yuan Yixin, ,Ban Molu ...... page:118-123 The effect of miR-497 on laryngeal squamous cell carcinoma invasion through modulating PlexinA4 (miR-497调控PlexinA4对喉鳞状细胞癌侵袭的影响) Niu Juntao, ,Liu Shuguang, ,Huang Yongwang, ,Li Chao ...... page:124-130 Correlation between patulous Eustachian tube with habitual nasal extraction and acquired middle ear cholesteatoma (咽鼓管异常开放伴习惯性抽鼻与后天性中耳胆脂瘤的关系) Fu Tao, ,Zhang Kun, ,Zhang Xiaowen, ,Wang Zhiyuan ...... page:131-133 Study on bone metabolism in postmenopausal women with idiopathic benign paroxysmal positional vertigo (绝经后女性特发性良性阵发性位置性眩晕患者骨代谢的研究) Gu Chengyao, ,Han Weiwei, ,Wu Yunqin, ,Fan Zhenyi, ,Chen Caijing, ,Chen Huimin ...... page:134-137 Chylous leakage attributable to post-operation on piriformis undifferentiated sarcoma combined with squamous cell carcinoma:a case report (梨状窝未分化肉瘤合并鳞状细胞癌术后并发乳糜漏一例) Liao Hongming, ,Liu Yingxin, ,Nan Haijing, ,Jiang Xian ...... page:138-140 IgG4-related sclerosing disease with initial ear symptom: a case report (以耳部病变为首发症状的IgG4相关硬化性疾病一例) Hu Ming, ,Wang Wei, ,Cheng Yan ...... page:140-143 One case of ossifying fibroma of the temporal bone with middle ear cholesteatoma (颞骨骨瘤合并胆脂瘤一例) Zhang Qiuyun, ,Lin Chang ...... page:143-145 Paranasal peripheral primitive neuroectodermal tumor:a case report (鼻旁外周原始神经外胚层肿瘤一例) Zhu Guochen ...... page:145-147 Inflammatory myofibroblastic tumor of thyroid:a case report (甲状腺炎性肌纤维母细胞瘤一例) An Ning, ,Luo Yan, ,Wang Jun, ,Wang Xiaolong, ,Man Guodong, ,Song Yiding ...... page:148-149 Research progress of functional magnetic resonance imaging in mechanism studies of tinnitus (功能性磁共振成像应用于耳鸣机制研究进展) Ji Bobo, ,Li Ming, ,Zhang Jianning ...... page:150-154 Mechanisms underlying glucocorticoid resistance in chronic rhinosinusitis with nasal polyps (慢性鼻-鼻窦炎伴鼻息肉治疗中糖皮质激素抵抗的机制) Zhang Yunyun, ,Lou Hongfei, ,Wang Chengshuo, ,Zhang Luo ...... page:154-160 CAOD TOC Alerts Note Thank you for choosing CAOD Table of Contents (TOC) Alert Service. You are receiving this email because you have requested to receive information from CAOD as a registered user of our Table of Content Alert for journals. To manage your TOC Alerts, please click here. For all enquiries, problems or suggestions regarding this service, please contact info@oriprobe.com. China/Asia on Demand (CAOD) Customer Service

Nanomechanics and ultrastructure of the internal mammary artery adventitia in patients with low and high pulse wave velocity

Publication date: Available online 21 April 2018
Source:Acta Biomaterialia
Author(s): Zhuo Chang, Paolo Paoletti, Steve D. Barrett, Ya Hua Chim, Eva Caamaño-Gutiérrez, Maria Lyck Hansen, Hans Christian Beck, Lars Melholt Rasmussen, Riaz Akhtar
The collagen-rich adventitia is the outermost arterial layer and plays an important biomechanical and physiological role in normal vessel function. While there has been a lot of effort to understand the role of the medial layer on arterial biomechanics, the adventitia has received less attention. In this study, we hypothesized that different ultrastructural and nanomechanical properties would be exhibited in the adventitia of the internal mammary artery (IMA) in patients with a low degree of arterial stiffening as compared to those with a high degree of arterial stiffening. Human IMA biopsies were obtained from a cohort of patients with arterial stiffening assessed via carotid-femoral PWV. Patients were grouped as low PWV (8.5±0.7 ms^-1, n=8) and high PWV (13.4±3.0 ms^-1, n=9). Peakforce QNM Atomic force microscopy (AFM) was used to determine the nanomechanical and morphological properties of the IMA. The nano-scale elastic modulus was found to correlate with PWV. We show for the first time that nano-scale alterations in adventitial collagen fibrils in the IMA are evident in patients with high PWV, even though the IMA is not involved in the carotid-femoral pathway. Our approach provides new insight into systemic structure-property changes in the vasculature, and also provides a method of characterizing small biopsy samples to predict the development of arterial stiffening.STATEMENT OF SIGNIFICANCEArterial stiffening occurs as part of the natural aging process and is strongly linked to cardiovascular risk. Although arterial stiffening is routinely measured in vivo, little is known about how localised changes in artery structure and biomechanics contributes to in vivo arterial stiffening. This study focusses on the role of the outermost layer of arteries, the adventitia, in arterial stiffening. The study provides data on nano-scale changes in collagen fibril structure and mechanical properties in the adventitia and shows how it relates to in vivo stiffness measurements in the vascular system. This is the first study to link in vivo arterial stiffening with nanomechanical changes artery biopsy samples. Hence, this approach could be used to develop new diagnostic methods for vascular disease.

Graphical abstract

https://ift.tt/2Jhh9Ah

Multi-Scale Structural Design and Biomechanics of the Pistol Shrimp Snapper Claw

Publication date: Available online 21 April 2018
Source:Acta Biomaterialia
Author(s): Shahrouz Amini, Maryam Tadayon, J.Q. Isaiah Chua, Ali Miserez
The Arthropoda, the largest phylum of the Animal Kingdom, have successfully evolved to survive various ecological constraints under a wide range of environmental conditions. Central to this survival are the structural designs developed in their exoskeletons and their raptorial appendages for protection and hunting. One such example, the pistol shrimp, is a shallow-water crustacean that is well-known for its aggressive hunting behavior, using its snapper claw to trigger the nucleation of cavitation bubbles that strike targets. In this study, we conducted a multi-scale structural/nanomechanics relationship study of this biotool to analyze its mechanical response to contact stresses. We found that the pistol shrimp snapper claw, which exhibits the capacity to emit a high-velocity water jet during rapid closure actions, is more brittle than other mineralized biotools, with accelerated wear damage under contact stresses. However, due to an angular offset between the dactylus and pollex of the snapper claw, the appendage never engages in any mechanical contact during the snapping action. This feature is in stark contrast to that reported in other fast raptorial appendages of crustaceans, notably the mantis shrimp dactyl club, which is designed to shatter close range targets in contact mode and exhibits a superior resistance to contact damages and wear. These findings suggest that adaptation of hunting appendages goes beyond their macroscopic morphology, and that multi-scale structural design concomitantly adapted to function, with enhanced structural complexification for tools that are subjected to more intense contact stresses.Statement of SignificanceThe evolution success of crustaceans is largely due to the diversification of their mineralized exoskeletons and hunting appendages, which exhibit a large palette of morphometric characteristics that have adapted to meet particular functions. We explored the "snapper claw" of the pistol shrimp, which is used to generate cavitation bubbles and strike prey. Our multi-scale structure-property relationship study reveals that the snapper claw is more brittle than other fast raptorial appendages –such as the stomatopod dactyl club– because it is not directly subjected to direct contact forces during action. This study implies that when higher mechanical stresses are needed to meet the function, the internal structure is built of a more complex architecture that allows to mitigate internal structural damage.

Graphical abstract

https://ift.tt/2HHMjDR

Injectable drug depot engineered to release multiple ophthalmic therapeutic agents with precise time profiles for postoperative treatment following ocular surgery

Publication date: Available online 21 April 2018
Source:Acta Biomaterialia
Author(s): Maziar Mohammadi, Kisha Patel, Seyedeh P. Alaie, Ron B. Shmueli, Cagri G. Besirli, Ronald G. Larson, Jordan J. Green
A multi-drug delivery platform is developed to address current shortcomings of post-operative ocular drug delivery. The sustained biodegradable drug release system is composed of biodegradable polymeric microparticles (MPs) incorporated into a bulk biodegradable hydrogel made from triblock copolymers with poly(ethylene glycol) (PEG) center blocks and hydrophobic biodegradable polyester blocks such as poly(lactide-co-glycolide) (PLGA), Poly(lactic acid) (PLA), or Poly(lactide-co-caprolactone) (PLCL) blocks. This system is engineered to flow as a liquid solution at room temperature for facile injection into the eye and then quickly gel as it warms to physiological body temperatures (approximately 37 °C). The hydrogel acts as an ocular depot that can release three different drug molecules at programmed rates and times to provide optimal release of each species. In this manuscript, the hydrogel is configured to release a broad-spectrum antibiotic, a potent corticosteroid, and an ocular hypotensive, three ophthalmic therapeutic agents that are essential for post-operative management after ocular surgery, each drug released at its own timescale. The delivery platform is designed to mimic current topical application of postoperative ocular formulations, releasing the antibiotic for up to a week, and the corticosteroid and the ocular hypotensive agents for at least a month. Hydrophobic blocks, such as PLCL, were utilized to prolong the release duration of the biomolecules. This system also enables customization by being able to vary the initial drug loading to linearly tune the drug dose released, while maintaining a constant drug release profile over time. This minimally invasive biodegradable multi-drug delivery system is capable of replacing a complex ocular treatment regimen with a simple injection. Such a depot system has the potential to increase patient medication compliance and reduce both the immediate and late term complications following ophthalmic surgery.Statement of SignificanceAfter ocular surgery, patients routinely receive multiple medications including antibiotics, steroids and ocular hypotensives to ensure optimal surgical outcomes. The current standard of care for postoperative treatment after ocular surgery involves using eye drops daily, which has limited effectiveness mainly due to poor patient adherence. To improve patient experience and outcomes, this article presents the first thermoresponsive hydrogel able to release multiple drug molecules for the application of post-operative treatment following ocular surgery. By varying the parameters such as hydrogel type and polymer hydrophobicity, the drug release profile, duration and dosage can finely be tuned. The approach presented in this article can readily be applied to other applications by simply changing the drug loaded in the drug delivery system.

Graphical abstract

https://ift.tt/2HiJ421

Component effect of stem cell-loaded thermosensitive polypeptide hydrogels on cartilage repair

Publication date: Available online 21 April 2018
Source:Acta Biomaterialia
Author(s): He Liu, Yilong Cheng, Jinjin Chen, Fei Chang, Jincheng Wang, Jianxun Ding, Xuesi Chen
Biophysical properties of the desired biomimetic scaffolds, such as porosity and elasticity, have been proven associated with the efficacy of cartilage regeneration. In this work, the copolymers of poly(L-alanine)-block-poly(ethylene glycol)-block-poly(L-alanine) (PA-PEG-PA) and poly(L-alanine-co-L-phenylalanine)-block-poly(ethylene glycol)-block-poly(L-alanine-co-L-phenylalanine) (PAF-PEG-PAF) with different ratios of alanine to phenylalanine were synthesized. The introduction of a hydrophobic amino acid, phenylalanine, into polyalanine-based thermosensitive hydrogel leaded to the enhanced gelation behaviors and upregulated mechanical properties. Moreover, the increase of phenylalanine content resulted in the enlarged pore size and enhanced mechanical strength of PAF-PEG-PAF thermogel, followed by the regeneration of hyaline-like cartilage with reduced fibrous tissue formation. The findings indicated the great potential of thermosensitive polypeptide hydrogels in cartilage tissue engineering.Statement of SignificanceArticular cartilage defect has limited self-repair ability due to the lack of blood supply and innervation, which may lead to knee osteoarthritis afterwards. Injectable hydrogels are demonstrated possessing outstanding properties as biomimetic scaffolds in cartilage tissue engineering, while the effect of biophysical properties on the efficacy of cartilage regeneration has not been revealed. Herein, the poly(ethylene glycol)−polypeptide triblock copolymers with different ratios of alanine to phenylalanine were synthesized. The sol-to-gel transition temperature and the critical gelling concentration decreased as the increased amount of phenylalanine units, resulting in the enlarged pore size and enhanced mechanical strength. These features lead to better regeneration of hyaline-like cartilage with reduced fibrous tissue formation, indicating great potential of thermosensitive polypeptide hydrogels for efficient cartilage repair.

Graphical abstract

https://ift.tt/2HFzee8

Decoration of RGD-mimetic Porous Scaffolds with Engineered and Devitalized Extracellular Matrix for Adipose Tissue Regeneration

Publication date: Available online 21 April 2018
Source:Acta Biomaterialia
Author(s): Eleonora Rossi, Julien Guerrero, Paola Aprile, Alessandro Tocchio, Elisabeth A Kappos, Cristina Lenardi, Ivan Martin, Arnaud Scherberich
Fat grafting is emerging as a promising alternative to silicon implants in breast reconstruction surgery. Unfortunately, this approach does not provide a proper mechanical support and is affected by drawbacks such as tissue resorption and donor site morbidity. Synthetic scaffolds can offer a valuable alternative to address these challenges, but poorly recapitulate the biochemical stimuli needed for tissue regeneration. Here, we aim at combining the positive features of a structural, synthetic polymer to an engineered, devitalized extracellular matrix (ECM) to generate a hybrid construct that can provide a mix of structural and biological stimuli needed for adipose tissue regeneration. A RGD-mimetic synthetic scaffold OPAAF, designed for soft tissue engineering, was decorated with ECM deposited by human adipose stromal cells (hASCs). The adipoinductive potential of the hybrid ECM-OPAAF construct was validated in vitro, by culture with hASC in a perfusion bioreactor system, and in vivo, by subcutaneous implantation in nude mouse. Our findings demonstrate that the hybrid ECM-OPAAF provides proper mechanical support and adipoinductive stimuli, with potential applicability as off-the-shelf material for adipose tissue reconstruction.Statement of significanceIn this study we combined the functionalities of a synthetic polymer with those of an engineered and subsequently devitalized extracellular matrix (ECM) to generate a hybrid material for adipose tissue regeneration. The developed hybrid ECM-OPAAF was demonstrated to regulate human adipose stromal cells adipogenic commitment in vitro and adipose tissue infiltration in vivo. Our findings demonstrate that the hybrid ECM-OPAAF provide proper mechanical support and adipoinductive stimuli and represents a promising off-the-shelf material for adipose tissue reconstruction.We believe that our approach could offer an alternative strategy for adipose tissue reconstruction incase of mastectomy or congenital abnormalities, overcoming the current limitations of autologous fat based strategies such as volume resorption and donor site morbidity.

Graphical abstract

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Using a gradient boosting model to improve the performance of low-cost aerosol monitors in a dense, heterogeneous urban environment

Publication date: July 2018
Source:Atmospheric Environment, Volume 184
Author(s): Nicholas E. Johnson, Bartosz Bonczak, Constantine E. Kontokosta
The increased availability and improved quality of new sensing technologies have catalyzed a growing body of research to evaluate and leverage these tools in order to quantify and describe urban environments. Air quality, in particular, has received greater attention because of the well-established links to serious respiratory illnesses and the unprecedented levels of air pollution in developed and developing countries and cities around the world. Though numerous laboratory and field evaluation studies have begun to explore the use and potential of low-cost air quality monitoring devices, the performance and stability of these tools has not been adequately evaluated in complex urban environments, and further research is needed. In this study, we present the design of a low-cost air quality monitoring platform based on the Shinyei PPD42 aerosol monitor and examine the suitability of the sensor for deployment in a dense heterogeneous urban environment. We assess the sensor's performance during a field calibration campaign from February 7th to March 25th 2017 with a reference instrument in New York City, and present a novel calibration approach using a machine learning method that incorporates publicly available meteorological data in order to improve overall sensor performance. We find that while the PPD42 performs well in relation to the reference instrument using linear regression (R² = 0.36–0.51), a gradient boosting regression tree model can significantly improve device calibration (R² = 0.68–0.76). We discuss the sensor's performance and reliability when deployed in a dense, heterogeneous urban environment during a period of significant variation in weather conditions, and important considerations when using machine learning techniques to improve the performance of low-cost air quality monitors.

Graphical abstract

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Secondary organic aerosol and ozone formation from photo-oxidation of unburned diesel fuel in a surrogate atmospheric environment

Publication date: July 2018
Source:Atmospheric Environment, Volume 184
Author(s): Weihua Li, David R. Cocker
Diesel fuel is a complex mixture of intermediate volatility organic compounds (IVOCs). Previous studies focused on secondary organic aerosol (SOA) and ozone formation from photo-oxidation of organic vapor from diesel exhaust and their components such as aromatics and heavy alkanes. However, there are few studies on atmospheric behavior of unburnt diesel. Therefore, in this study, ten unburnt #2 commercial diesel samples and one FACE9A research diesel fuel were photo-oxidized in the University of California Riverside, College of Engineering-Center for Environmental Research & Technology dual environmental chambers to investigate their SOA and ozone production potential. Photochemical aging rapidly produced significant SOA (yield ∼20.3–37.7%) in the presence of a surrogate reactive organic gas (ROG) mixture used to mimic urban atmospheric reactivity. SOA yields were consistent with n-Heptadecane yields under similar conditions. Doubling NOx concentrations within relevant urban concentration levels enhanced SOA formation by 33% and ozone formation by 48%. SOA formation in this study was approximately fourteen times higher than previously reported for very high NOx conditions. An SOA experiment designed to mimic the previous work achieved similar yields to the earlier work. SOA formed under urban relevant NOx concentrations were consistent with semi-volatile-oxygenated organic aerosol (SV-OOA) and underwent little further chemical processing once produced.



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Emission characteristics of NOx, CO, NH3 and VOCs from gas-fired industrial boilers based on field measurements in Beijing city, China

Publication date: July 2018
Source:Atmospheric Environment, Volume 184
Author(s): Tao Yue, Xiang Gao, Jiajia Gao, Yali Tong, Kun Wang, Penglai Zuo, Xiaoxi Zhang, Li Tong, Chenlong Wang, Yifeng Xue
In the past decade, due to the management policies and coal combustion controls in Beijing, the consumption of natural gas has increased gradually. Nevertheless, the research on the emission characteristics of gaseous pollutants emitted from gas-fired industrial boilers, especially considering the influence of low nitrogen (low-NOx) retrofit policy of gas boilers, is scarcely. In this study, based on literature and field investigations, onsite measurements of NOx, CO, NH3 and VOCs (Volatile Organic Compounds) emissions from gas-fired industrial boilers as well as the key factors that affected the emission of gaseous pollutants were discussed. Category-specific emission factors (EFs) of NOx, CO, NH3 and VOCs were obtained from the field measurements of 1107 "low-NOx" retrofitted and unabated gas-fired industrial boilers. Our results showed that operating load and control measures were the two key factors affecting the formation of gaseous pollutants. The EFs of NOx (EFNOx) and CO (EFCO) of atmospheric combustion boilers (ACBs) were much higher than the EFs of chamber combustion boilers (CCBs). The total emissions of NOx, CO, NH3 and VOCs from gas-fired industrial boilers in Beijing in the year of 2015 were estimated at 10489.6 t, 3272.8 t, 196.4 t and 235.4 t, respectively. Alkanes, BTEX, oxygenated VOCs and non-reactive organic matter were the four main chemical components of VOCs. As for the spatial distributions, the emissions of NOx, CO, NH3 and VOCs from gas-fired industrial boilers in Beijing were predominantly concentrated in central six urban districts. In the future, more detailed investigation and field tests for all kinds of gas-fired industrial boilers are still greatly needed to achieve more reliable estimations of atmospheric pollutants from gas-fired industrial boilers.



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Long-term systematic profiling of dust aerosol optical properties using the EOLE NTUA lidar system over Athens, Greece (2000–2016)

Publication date: June 2018
Source:Atmospheric Environment, Volume 183
Author(s): O. Soupiona, A. Papayannis, P. Kokkalis, M. Mylonaki, G. Tsaknakis, A. Argyrouli, S. Vratolis
We present a comprehensive analysis of the seasonal variability of the vertical profiles of the optical and geometrical properties of Saharan dust aerosols, observed in the height region between 1000 and 6000 m, over the city of Athens, Greece, from February 2000 to December 2016. These observations were performed by a multi-wavelength (355-387-532-1064 nm) Raman lidar system under cloud-free conditions. The statistical analysis (using aerosol monthly mean values) is based on nighttime vertical Raman measurements of range-resolved aerosol optical properties (backscatter and extinction coefficients, lidar ratio, Ångström exponent) at 355 nm (57 dust events during more than 80 measurement hours). We found that the number of dust events was highest in spring, summer, and early autumn periods and that during spring the dust layers were moved at higher altitudes (∼4500 m) than in other seasons. The number of the forecasted dusty days (on monthly basis) by the BSC-DREAM8b model compared to those of the performed lidar measurements were found to have a quite strong correlation (R² = 0.81), with a maximum occurrence predicted for the spring season. In the worst case scenario, at least 50% of the model-forecasted dust events can be observed by lidar under cloudless skies over Athens. For the sampled dust plumes we found mean lidar ratios of 52 ± 13 sr at 355 nm in the height range 2000–4000 m a.s.l. Moreover, the dust layers had a mean thickness of 2497 ± 1026 m and a center of mass of 2699 ± 1017 m.An analysis performed regarding the air mass back-trajectories arriving over Athens revealed two main clusters: one pathway from south-west to north-east, with dust emission areas in Tunisia, Algeria and Libya and a second one from south, across the Mediterranean Sea with emission areas over Libya and the remaining part of Algeria and Tunisia. This clustering enabled us to differentiate between the aerosol optical properties between the two clusters, based on their residence time over the Saharan region, the European continent and the Mediterranean Sea. We finally concluded that even if the dust source regions are about the same, the aging and mixing processes of these air masses, passing over different areas, might have an impact on the aerosol optical properties.

Graphical abstract

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Variability in impact of air pollution on subjective well-being

Publication date: June 2018
Source:Atmospheric Environment, Volume 183
Author(s): Guodong Du, Kong Joo Shin, Shunsuke Managi
This paper examines the impact of variability in impact of air pollution on life satisfaction (LS). Previous studies have shown robust negative impact of air pollution on subjective well-being (SWB). However, empirical studies that consider variability in air pollution effects through comparative city study are limited. This study provides comparative evaluation of two major Chinese cities: Beijing and Shanghai. We apply a geo-statistical spatial interpolation technique on pollution data from monitoring sites to estimate the Sulfur Dioxide (SO2), Nitrogen Dioxide (NO2), coarse particles with a diameter between 2.5 and 10 μm (PM10) and fine particles with a diameter of 2.5 μm or less (PM2.5) pollution exposure of respondents of a survey conducted in 2016. The results show that all pollutants have robust negative impacts on LS for Beijing residents, whereas only SO2 and NO2 have significant negative impacts on LS for Shanghai residents; Per unit impact of SO2 is greater in Shanghai, and that of NO2 is greater in Beijing. Beijing and Shanghai residents have almost same monetary valuation for SO2 reduction but Beijing residents place approximately 1.5 times valuation on NO2 reduction compared to Shanghai residents. Moreover, the LS of Beijing residents is sensitive to temporal changes in the pollution level, whereas Shanghai residents are unaffected by such changes.



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Meat allergy and allergens

Publication date: Available online 21 April 2018
Source:Molecular Immunology
Author(s): Jeffrey M. Wilson, Thomas A.E. Platts-Mills
IgE-mediated hypersensitivity to ingested animal products, including both mammalian and avian sources, is increasingly appreciated as an important form of food allergy. Traditionally described largely in children, it is now clear that allergy to meat (and animal viscera) impacts both children and adults and represents a heterogeneous group of allergic disorders with multiple distinct syndromes. The recognition of entities such as pork-cat syndrome and delayed anaphylaxis to red meat, i.e- the α-Gal syndrome, have shed light on fundamental, and in some cases newly appreciated, features of allergic disease. These include insights into routes of exposure and mechanisms of sensitization, as well as the realization that IgE-mediated reactions can be delayed by several hours. Here we review mammalian and avian meat allergy with an emphasis on the molecular allergens and pathways that contribute to disease, as well as the role of in vitro IgE testing in diagnosis and management.



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Clinical Thyroidology®for the Public – Highlighted Article

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