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Τετάρτη 20 Ιουνίου 2018
Scholar : These new articles for Advances in Mental Health are available online
Tweeting about measles during stages of an outbreak: A semantic network approach to the framing of an emerging infectious disease
Source:American Journal of Infection Control
Author(s): Lu Tang, Bijie Bie, Degui Zhi
BackgroundThe public increasingly uses social media not only to look for information about emerging infectious diseases (EIDs), but also to share opinions, emotions, and coping strategies. Identifying the frames used in social media discussion about EIDs will allow public health agencies to assess public opinions and sentiments.MethodThis study examined how the public discussed measles during the measles outbreak in the United States during early 2015 that originated in Disneyland Park in Anaheim, CA, through a semantic network analysis of the content of around 1 million tweets using KH coder.ResultsFour frames were identified based on word frequencies and co-occurrence: news update, public health, vaccination, and political. The prominence of each individual frame changed over the corse of the pre-crisis, initial, maintenance, and resolution stages of the outbreak.ConclusionsThis study proposed and tested a method for assessing the frames used in social media discussions about EIDs based on the creation, interpretation, and quantification of semantic networks. Public health agencies could use social media outlets, such as Twitter, to assess how the public makes sense of an EID outbreak and to create adaptive messages in communicating with the public during different stages of the crisis.
https://ift.tt/2MJevGb
Association of human beta‐defensin 1 gene polymorphisms with nonsegmental vitiligo
Clinical and Experimental Dermatology, EarlyView.
https://ift.tt/2KaDC6b
Aciclovir for treatment of pityriasis lichenoides?
Clinical and Experimental Dermatology, EarlyView.
https://ift.tt/2K2tysI
Actinic Keratosis Area Severity Index (AKASI): reproducibility study and comparison with total lesion count
British Journal of Dermatology, EarlyView.
https://ift.tt/2K3sMyZ
Herpetiform pemphigus with characteristic transmission electron microscopic findings of various‐sized ballooning vacuoles in keratinocytes without acantholysis
British Journal of Dermatology, EarlyView.
https://ift.tt/2I7ynz4
Clinical and dermoscopic features of Spitz naevus by sex, age and anatomical site: a study of 913 Spitz naevi
British Journal of Dermatology, EarlyView.
https://ift.tt/2K7KUrm
Early detection of gastric cancer after Helicobacter pylori eradication due to endoscopic surveillance
Helicobacter, EarlyView.
https://ift.tt/2JTuSlN
Tie-Break: Host and Retrotransposons Play tRNA
Publication date: Available online 19 June 2018
Source:Trends in Cell Biology
Author(s): Andrea J. Schorn, Rob Martienssen
tRNA fragments (tRFs) are a class of small, regulatory RNAs with diverse functions. 3′-Derived tRFs perfectly match long terminal repeat (LTR)-retroelements which use the 3′-end of tRNAs to prime reverse transcription. Recent work has shown that tRFs target LTR-retroviruses and -transposons for the RNA interference (RNAi) pathway and also inhibit mobility by blocking reverse transcription. The highly conserved tRNA primer binding site (PBS) in LTR-retroelements is a unique target for 3′-tRFs to recognize and block abundant but diverse LTR-retrotransposons that become transcriptionally active during epigenetic reprogramming in development and disease. 3′-tRFs are processed from full-length tRNAs under so far unknown conditions and potentially protect many cell types. tRFs appear to be an ancient link between RNAi, transposons, and genome stability.
https://ift.tt/2yyMZb4
Transient aphasia after right-unilateral ultrabrief electroconvulsive therapy: A case report
Source:Brain Stimulation
Author(s): J. Buday, J. Albrecht, T. Mares, J. Raboch, M. Anders
A brief period of aphasia is an extremely rare and likely underreported adverse effect of electroconvulsive therapy. Clinical studies that have described this phenomenon are scarce and its prevalence is unknown. We present a unique case of a 35-year old woman, who underwent an outpatient ECT session at our department, followed by a short span of aphasic symptoms, the extent of which were monitored clinically and via the czech version of the Minnesota aphasia screening test.
https://ift.tt/2llbqiR
A Conversation with Swiss Product Designer, Christophe Guberan
3D Printing and Additive Manufacturing, Volume 5, Issue 2, Page 87-89, June 2018.
https://ift.tt/2K3wEN2
Development of 3D-Printed Embedded Temperature Sensor for Both Terrestrial and Aquatic Environmental Monitoring Robots
3D Printing and Additive Manufacturing, Volume 5, Issue 2, Page 160-169, June 2018.
https://ift.tt/2K9Ub20
3D-Printed Reusable Cell Culture Chamber with Integrated Electrodes for Electrical Stimulation and Parallel Microscopic Evaluation
3D Printing and Additive Manufacturing, Volume 5, Issue 2, Page 115-125, June 2018.
https://ift.tt/2K6H6mP
GridLoc: An automatic and unsupervised localization method for high-density ECoG grids
Publication date: 1 October 2018
Source:NeuroImage, Volume 179
Author(s): Mariana P. Branco, Michael Leibbrand, Mariska J. Vansteensel, Zachary V. Freudenburg, Nick F. Ramsey
Precise localization of electrodes is essential in the field of high-density (HD) electrocorticography (ECoG) brain signal analysis in order to accurately interpret the recorded activity in relation to functional anatomy. Current localization methods for subchronically implanted HD electrode grids involve post-operative imaging. However, for situations where post-operative imaging is not available, such as during acute measurements in awake surgery, electrode localization is complicated. Intra-operative photographs may be informative, but not for electrode grids positioned partially or fully under the skull. Here we present an automatic and unsupervised method to localize HD electrode grids that does not require post-operative imaging. The localization method, named GridLoc, is based on the hypothesis that the anatomical and vascular brain structures under the ECoG electrodes have an effect on the amplitude of the recorded ECoG signal. More specifically, we hypothesize that the spatial match between resting-state high-frequency band power (45–120 Hz) patterns over the grid and the anatomical features of the brain under the electrodes, such as the presence of sulci and larger blood vessels, can be used for adequate HD grid localization. We validate this hypothesis and compare the GridLoc results with electrode locations determined with post-operative imaging and/or photographs in 8 patients implanted with HD-ECoG grids. Locations agreed with an average difference of 1.94 ± 0.11 mm, which is comparable to differences reported earlier between post-operative imaging and photograph methods. The results suggest that resting-state high-frequency band activity can be used for accurate localization of HD grid electrodes on a pre-operative MRI scan and that GridLoc provides a convenient alternative to methods that rely on post-operative imaging or intra-operative photographs.
https://ift.tt/2Ib5cuW
Quality control of goji (fruits of Lycium barbarum L. and L. chinense Mill.): A value chain analysis perspective
Publication date: 5 October 2018
Source:Journal of Ethnopharmacology, Volume 224
Author(s): Ruyu Yao, Michael Heinrich, Zigui Wang, Caroline S. Weckerle
Ethnopharmacological relevanceGoji (fruits of Lycium barbarum L. and L. chinense Mill., Solanaceae) have been used as a traditional food and medicine for hundreds of years in Asian countries and are now consumed globally. Quality of herbal medicines is critical for safe use and has been shown to be affected by value chains.Aim of the studyUsing a value chain (VC) framework, we aim at understanding the influence of different VC types on goji quality and revenue of stakeholders.Materials and methodsParticipant observation and semi-structured interviews were conducted during five months of fieldwork in the main production areas in China with a total of 65 stakeholders. Quality of goji, behaviour and financial performance of stakeholders was documented and analysed for different VCs.ResultsTen different types of VCs were identified. VCs with vertical integration and horizontal collaboration were found to have a more coherent quality control and better goji quality as well as improved stakeholders' financial performance. Vertical integration at different levels was found for independent farmer-based VCs, horizontal collaboration was found in the cooperative-based VCs. Full vertically integrated VCs were found in large-scale production.ConclusionsGoji quality and stakeholders' revenues are linked with different types of VCs which mirror stakeholders' behaviour driven by target markets. Considering their positive influence on quality and revenues, well-developed vertically integrated value chains are likely to become more important in the near future.
Graphical abstract
https://ift.tt/2KcwR3E
Pharmacological and toxicological study of a chemical-standardized ethanol extract of the branches and leaves from Eysenhardtia polystachya (Ortega) Sarg. (Fabaceae)
Publication date: 5 October 2018
Source:Journal of Ethnopharmacology, Volume 224
Author(s): Angel Josabad Alonso-Castro, Juan Ramón Zapata-Morales, Victor Arana-Argáez, Julio Cesar Torres-Romero, Eyra Ramírez-Villanueva, Sabino Eduardo Pérez-Medina, Marco Antonio Ramírez-Morales, Mario Alberto Juárez-Méndez, Yessica Paola Infante-Barrios, Fidel Martínez-Gutiérrez, Candy Carranza-Álvarez, Mario Alberto Isiordia-Espinoza, Andrés Flores-Santos
Eysenhardtia polystachya is used for the empirical treatment of cancer, infections, diarrhea, inflammation, and pain. This study identified, using GC-MS, the main chemical components in an ethanol extract of E. polystachya branches and leaves (EPE) and tested its cytotoxic, antimicrobial, anti-diarrheal, anti-inflammatory, and antinociceptive effects. The in vitro and in vivo toxicity of EPE was evaluated using the comet assay in human peripheral blood mononuclear cells (PBMC) and the acute toxicity test in mice, respectively. The cytotoxic and the antimicrobial effects were performed using the MTT assay and the minimum inhibitory concentration (MIC) test, respectively. The levels of pro-inflammatory mediators in LPS-stimulated macrophages were measured to evaluate the in vitro anti-inflammatory effects of EPE. The antidiarrheal (castor oil test, small intestine transit, and castor oil-induced enteropooling), and anti-inflammatory activities (TPA and carrageenan) of EPE were also performed. The antinociceptive actions of EPE were carried out with the following tests: acetic acid, formalin, and hot plate. The hypnotic and locomotor effects were analyzed using pentobarbital and a rotarod system, respectively. The main component in EPE was D-pinitol (26.93%). The antidiarrheal and antinociceptive effects of D-pinitol were also evaluated. EPE showed low in vitro toxicity (DNA damage in PBMC at concentrations higher than 200 µg/ml), and low in vivo toxicity (LD50 > 2000 mg/kg i.p. and p.o.). Furthermore, EPE lacked cytotoxic activity (IC50 > 300 µg/ml) on human cancer cells, but showed good antimicrobial effects in E. coli (MIC=1.56 µg/ml) and S. aureus (MIC = 0.78 µg/ml). In multi-drug resistant microorganisms, EPE showed MIC> 100 µg/ml. EPE exerted in vitro anti-inflammatory effects, mainly, by the decrease in the production of H2O2 (IC50 = 43.9 ± 3.8 µg/ml), and IL-6 (73.3 ± 6.9 µg/ml). EPE (ED50 =7.5 ± 0.9 mg/kg) and D-pinitol (ED50 = 0.1 ± 0.03 mg/kg) showed antidiarrheal activity, and antinociceptive effects in the acetic acid test with ED50 = 117 ± 14.5 mg/kg for EPE and 33 ± 3.2 mg/kg for D-pinitol. EPE showed also antinociceptive activity in the phase 2 of the formalin test (ED50 = 48.9 ± 3.9 mg/kg), without inducing hypnotic effects or altering the locomotor activity in mice. The results here presented corroborate the folk medicinal use of Eysenhardtia polystachya in the treatment of infections, diarrhea, inflammation, and pain. D-pinitol, the main metabolite of EPE, showed antinociceptive and antidiarrheal effects with similar potency compared to standard drugs.
Graphical abstract
https://ift.tt/2K30ykC
Patterns of change: The dynamics of medicinal plant trade in far-western Nepal
Publication date: 5 October 2018
Source:Journal of Ethnopharmacology, Volume 224
Author(s): Dipesh Pyakurel, Indira Bhattarai Sharma, Carsten Smith-Hall
Ethnopharmacological relevanceCombined quantitative and qualitative environmental product trade studies, undertaken in the same location over time, are instrumental in identifying plant species with commercial demand and explaining what drives temporal changes. Yet such dynamic studies are rare, including for Himalayan medicinal plants that have been large-scale traded for millennia.Aim of the studyTo (i) investigate changes in medicinal plant trade in the past 17 years, and (ii) identify the main factors driving changes, using a study of Darchula District in far-western Nepal.Materials and methodsMedicinal plant production network data were collected from March to August 2016, for the fiscal year 2014–15, for Darchula District in far-western Nepal through 167 quantitative (58 harvesters, 38 sub-local traders, 25 local traders, 25 central wholesalers, and 21 regional wholesalers), 61 qualitative (15 sub-local traders, 19 local traders, 15 central wholesalers, and 12 regional wholesalers) interviews, and four focus group discussions. Results were compared to previously unpublished similar data for Darchula District for the year 1997–98, using quantitative and qualitative interviews with 10 local traders, 20 central wholesalers, and 53 regional wholesalers. Data analysis was guided by an analytical framework derived from Global Production Network theory. Quantitative data were used to estimate changes in 12 indicators while the qualitative information allowed identification of the factors driving observed changes in the indicators.ResultsThe volume of medicinal plants traded from Darchula District in the fiscal year 2014–15 was 401 t with a harvester value of USD 5.5 million, representing a 2.3 fold increase in volume and 17.2 fold increase in value compared to 1997–98. Trade in the two observation years comprised 30 air-dried plant products (from 28 identified species as well as lichens and a mineral substance); 12 products were traded in both periods, while seven disappeared, and 11 new products entered the trade. The number of traders increased from 10 to 63, mainly due to the emergence of a single high value product yarsagumba (Ophiocordyceps sinensis), a fungus-caterpillar complex which alone contributed 85% of total trade value. Over the observed time period, harvesters and traders increased their margins at the cost of central wholesalers, indicating that market changes favoured lower tier actors, eroding the previously identified passive central wholesaler oligopsony in Nepal. Important drivers of market changes are: (i) rising incomes in China and India, expressed through demand for new products and increasing per unit prices for a range of products, (ii) expanding infrastructure (roads and telecommunications) towards and into harvesting sites, reducing transport costs and increasing market efficiency, and (iii) government interventions, causing disappearance of some species from trade. These market changes also led to increased cultivation at lower altitudes, and a sharp increase in the number of processor industries in Nepal.ConclusionTrade in medicinal plant products in far-western Nepal in the past two decades has increased substantially, doubling in volume and increasing 17 fold in value. There is a backbone of constantly traded species but also species that disappear from trade and new species that enter. Changes favour harvesters and traders at the benefit of central wholesalers whose previous passive oligopsony is disappearing. The three main drivers of change are rising incomes in China and India, expanding infrastructure, and government interventions in Nepal. Commercial medicinal plant resources are a substantial asset that appears to offer opportunities for economic development in far-western Nepal. The trade, however, may pose sustainability threats that are best understood by combining species-level biophysical, trade, and consumer studies.
Graphical abstract
https://ift.tt/2K499GP
Phenolic acid and flavonoid-rich fraction of Sasa quelpaertensis Nakai leaves prevent alcohol induced fatty liver through AMPK activation
Publication date: 5 October 2018
Source:Journal of Ethnopharmacology, Volume 224
Author(s): Kalahe Hewage Iresha Nadeeka Madushani Herath, Jinhee Cho, Areum Kim, Tae Kil Eom, Ju-Sung Kim, Jae-Bum Kim, Yang Hoi Doh, Youngheun Jee
Ethnopharmacological relevanceSasa quelpaertensis Nakai is an edible dwarf bamboo cultivated mainly in Jeju Island, South Korea and its leaf displays various health-promoting properties including antioxidant scavenging.Aim of the studyIn this study, we aimed at elucidating its hepatoprotective effect against alcohol-induced fatty liver.MethodsIn in vitro study, we evaluated the cytotoxicity and hepatoprotective effect of different solvent fractions (aqua, butanol, chloroform, ethyl acetate and hexane) of 80% EtOH extract of S. quelpaertensis Nakai leaf. In vivo experiment performed using binge alcohol consumption model.ResultsAlthough all five fractions (0–1000 µg/mL) were non-cytotoxic to HepG2 cells, only ethyl acetate fraction (SQEA), rich in phenolic acids such as p-coumaric acid and flavonoids particularly myristin, showed hepatoprotective effect against EtOH (400 mM) in HepG2 cells. Furthermore, SQEA significantly decreased the ethanol induced cell death and enhanced the cell proliferation. In in vivo experiment using binge consumption model (5 g of EtOH/kg body weight in every 12 h for 3 times), SQEA treatment (10, 50 and 100 mg/kg) markedly reduced the alcohol induced histopathological changes and serum EtOH content, and reversed the reduction of glutathione level in ethanol challenged livers. Further, it suppressed the expression of cytochrome P450 2E1 (CYP2E1). In particular, SQEA activated AMP activated protein kinase (AMPK) pathway, and decreased the expression of tumor necrosis factor receptor-1 (TNFR1), which attenuated lipogenesis via decreased expression of fatty acid synthase (FAS). Inhibited lipogenesis due to SQEA treatment directed towards decreased perilipin-2 expression. These results indicate that SQEA has hypolipidemic effect which is mediated by decreased oxidative stress, increased fatty acid oxidation response and decreased lipogenesis.ConclusionOur results suggest the possibility of developing SQEA as a natural hepatoprotective agent potent in attenuating alcohol-induced fatty liver.
Graphical abstract
https://ift.tt/2K3bG0V
Integrated in silico-in vitro strategy for screening of some traditional Egyptian plants for human aromatase inhibitors
Publication date: 5 October 2018
Source:Journal of Ethnopharmacology, Volume 224
Author(s): Hend M. Dawood, Reham S. Ibrahim, Eman Shawky, Hala M. Hammoda, Aly M. Metwally
Ethnopharmacological relevanceAromatase enzyme (CYP19) is widely known as a critical target protein for treating hormone-dependent breast cancer. Natural products from traditional medicinal plants continue to be an active source of aromatase inhibitors. Meanwhile, high cost of experimental work and low hit rate associated with HTS have stimulated the implementation of in-silico virtual screening to resolve these pitfalls, where coupling of both classical wet lab procedure and VS may offer a more deepened access to bioactive compounds with less work and time waste.Aim of the studyIn this work, a sequential structure-based and ligand-based virtual screening strategy was utilized for investigating an in-house database of 1720 phytochemical constituents of 29 medicinal plants and natural products used in traditional Egyptian medicine to search for compounds with the potential to be used as inhibitors of the human aromatase enzyme.Materials and methodsThe suggested strategy included using Glide docking with its feature 'extra precision (XP)' for carrying out structure-based virtual screening (SBVS) where the resulting hits were further promoted to ligand-based virtual screening (LBVS) through the development of two pharmacophore and QSAR models; one for steroidal and the other for non-steroidal aromatase inhibitors.ResultsThe combined results revealed that Artemisia annua, Zingiber officinale, Cicer arietinum, Annona muricata and Vitex agnus castus were the top scoring plants in terms of in-silico activity scores, respectively. The hydro-alcoholic extracts and different solvent fractions of the top scoring plants were subsequently tested experimentally for their aromatase inhibitory activity, by the aid of in-vitro fluorometric assay. The rank ordering of the activities for the plants agreed with the ordering predicted on the basis of SBVS and LBVS workflow implemented.ConclusionThe suggested strategy provides a reliable means of prospecting in-silico screening of natural products databases in the search for new dug leads as aromatase inhibitors. The hits so obtained can then be subjected to further phytochemical studies, to isolate and identify suitable compounds for further in-vitro testing.
Graphical abstract
https://ift.tt/2K5JvSa
Mahuang decoction mitigates airway inflammation and regulates IL-21/STAT3 signaling pathway in rat asthma model
Publication date: 5 October 2018
Source:Journal of Ethnopharmacology, Volume 224
Author(s): Yu He, Xiaohui Lou, Zhan Jin, Li Yu, Ling Deng, Haitong Wan
Ethnopharmacological relevanceNowadays, bronchial asthma is still a severe disease threatening human health, and it is incumbent upon us to seek effective therapeutic drugs. Mahuang decoction (MHD), a classic famous Chinese prescription, has been used for thousands of years to prevent phlegm from forming, stop coughing and relieve asthma, but the relevant mechanism has not been thoroughly clarified. This study aims to investigate the anti-airway inflammation effect of MHD and the possible molecular mechanism underlying IL21/STAT3 signaling pathway, so as to provide guidance for the treatment of MHD on bronchial asthma.Materials and methodsSpecific pathogen free SD rats were randomly divided into 6 groups: normal control group, model group, positive group (Compound methoxyphenamine), MHD-treated groups at doses of 10 ml/kg, 5 ml/kg and 2.5 ml/kg, 10 rats in each group. Except for the normal control group, rats in other groups were sensitized with ovalbumin via introperitoneal injection and challenged with ovalbumin inhalation to trigger asthma model. At 24 h after the last excitation, bronchoalveolar lavage fluid (BALF) of every rat was drawn and the number of inflammatory cells was analyzed using cell counting method. ELISA method was performed to determine the concentrations of TXB2, 6-keto-PGF1α, MMP-9, TIMP-1, IL-2, IL-4, IL-5 and TNF-α in rat serum. The protein expressions of IL-21, IL-21R, STAT3 and p-STAT3 in murine pulmonary tissues were assessed with western blotting analysis.ResultsCompared with the control group, the airway wall and airway smooth muscle of murine pulmonary tissues significantly thickened and massive inflammatory cells infiltration occurred around the bronchus in the model group, and the cell counts of WBC and EOS in BALF were also apparently increased, which indicated the rat asthma model was successfully established. MHD or Compound methoxyphenamine not only alleviated the pulmonary inflammatory pathological damages, but also down- regulated the numbers of WBC and EOS in BALF. What's more, the levels of TXB2, MMP-9, TIMP-1, ILs-(2, 4, 5) and TNF-α in rat serum were lessened by the treatment of MHD. In western blotting analysis, treatment with 10 ml/kg or 5 ml/kg MHD markedly declined the increased protein expressions of IL-21, IL-21R, STAT3 and p-STAT3 in lung tissues of asthmatic rats to normal level.ConclusionMHD intervention demonstrated a strong inhibitory action on the secretion of inflammatory mediators as well as the inflammatory cell infiltration in pulmonary tissues of asthmatic rats, and also depressed the protein expressions of IL-21, IL-21R, STAT3 and p-STAT3 in pulmonary tissues. MHD effectively mitigates airway inflammation and regulates the IL-21/STAT3 signaling pathway in rat asthma model.
Graphical abstract
https://ift.tt/2I5tQgE
Reactive oxygen species in cancer stem cells of head and neck squamous cancer
Source:Seminars in Cancer Biology
Author(s): Xu Qian, Xiaobo Nie, Wenhao Yao, Konrad Klinghammer, Holger Sudhoff, Andreas M. Kaufmann, Andreas E. Albers
One of the greatest challenges in systemic treatment of head and neck squamous cell carcinoma (HNSCC) is a small tumor cell population, namely, cancer stem-like cells (CSC). CSC can regenerate and maintain a heterogenic tumor by their self-renewal capacity. Their potential ability to be more resistant to and survival after chemo- and radiation therapy was also identified. Further studies have shown that reactive oxygen species (ROS) contribute to this CSC-associated resistance. In this review, we focus on the current knowledge of HNSCC-CSC, with regard to ROS as a possible and novel therapeutic approach in targeting CSC.
https://ift.tt/2M9FpWm
Hyperglycemia induces epithelial–mesenchymal transition in the lungs of experimental diabetes mellitus
Source:Acta Histochemica
Author(s): Chung-Ming Chen, Shu-Hui Juan, Man-Hui Pai, Hsiu-Chu Chou
Diabetes mellitus (DM) reduces lung function and increases the risk of asthma, chronic obstructive pulmonary disease, pneumonia, and pulmonary fibrosis. Epithelial–mesenchymal transition (EMT) plays a crucial role in the development of pulmonary fibrosis. The pathogenesis of pulmonary fibrosis in diabetes remains unknown. We investigated the effects of hyperglycemia on EMT in the lungs of gerbils with streptozotocin (STZ)-induced diabetes. Diabetic gerbils exhibited a significantly lower volume fraction of the alveolar airspace and significantly higher septal thickness, volume fraction of the alveolar wall, and lung injury scores than did nondiabetic gerbils. The percentage of 8-hydroxy-2′-deoxyguanosine-positive cells and transforming growth factor-β-positive cells was significantly higher, the expression of E-cadherin was significantly lower, and the expression of N-cadherin was significantly higher in diabetic gerbils than in nondiabetic gerbils. These EMT characteristics were associated with a significant increase in α-smooth muscle actin (SMA) expression and collagen deposition in the lungs of diabetic gerbils. The increased α-SMA expression was co-localized with surfactant protein-C in alveolar type II cells in hyperglycemic animals. In conclusion, our study demonstrates that hyperglycemia induces EMT and contributes to lung fibrosis in an experimental DM model.
https://ift.tt/2lkwxBV
Stimulation of calvarial bone healing with human bone marrow stromal cells versus inhibition with adipose-tissue stromal cells on nanostructured β-TCP-collagen
Publication date: Available online 20 June 2018
Source:Acta Biomaterialia
Author(s): Friederike Bothe, Benedict Lotz, Elisabeth Seebach, Jennifer Fischer, Eliane Hesse, Solvig Diederichs, Wiltrud Richter
Bioactive functional scaffolds are essential for support of cell-based strategies to improve bone regeneration. Adipose-tissue-derived-stromal cells (ASC) are more accessible multipotent cells with faster proliferation than bone-marrow-derived-stromal-cells (BMSC) having potential to replace BMSC for therapeutic stimulation of bone-defect healing. Their osteogenic potential is, however lower compared to BMSC, a deficit that may be overcome in growth factor-rich orthotopic bone defects with enhanced bone-conductive scaffolds. Objective of this study was to compare the therapeutic potency of human ASC and BMSC for bone regeneration on a novel nanoparticulate β-TCP/collagen-carrier (β-TNC).Cytotoxicity of β-TCP nanoparticles and multilineage differentiation of cells were characterized in vitro. Cell-seeded β-TNC versus cell-free controls were implanted into 4 mm calvarial bone-defects in immunodeficient mice and bone healing was quantified by µCT at 4 and 8 weeks. Tissue-quality and cell-origin were assessed by histology.β-TNC was non-toxic, radiolucent and biocompatible, lent excellent support for human cell persistence and allowed formation of human bone tissue by BMSC but not ASC. Opposite to BMSC, ASC-grafting significantly inhibited calvarial bone healing compared to controls. Bone formation progressed significantly from 4 to 8 weeks only in BMSC and controls yielding 5.6-fold more mineralized tissue in BMSC versus ASC-treated defects.Conclusively, β-TNC was simple to generate, biocompatible, osteoconductive, and stimulated osteogenicity of BMSC to enhance calvarial defect healing while ASC had negative effects. Thus, an orthotopic environment and β-TNC could not compensate for cell-autonomous deficits of ASC which should systematically be considered when choosing the right cell source for tissue engineering-based stimulation of bone regeneration.Statement of SignificanceBone-marrow-derived-stromal cells (BMSC) implanted on bone replacement materials can support bone defect healing and adipose-tissue-derived-stromal cells (ASC) being more accessible and better proliferating are considered as alternate source. This first standardized comparison of the bone regeneration potency of human ASC and BMSC was performed on a novel nanoparticular β-TCP-enriched collagen-carrier (β-TNC) designed to overcome the known inferior osteogenicity of ASC. β-TNC was non-toxic, biocompatible and osteoconductive supporting human bone formation and defect-closure by BMSC but not ASC. Long-term cell-persistence and the distinct secretome of ASC appear as main reasons why ASC inhibited bone healing opposite to BMSC. Overall, ASC-grafting is at considerable risk of producing negative effects on bone-healing while no such risks are known for BMSC.
Graphical abstract
https://ift.tt/2yuzSIc
In vitro response of mesenchymal stem cells to biomimetic hydroxyapatite substrates: a new strategy to assess the effect of ion exchange
Publication date: Available online 20 June 2018
Source:Acta Biomaterialia
Author(s): Joanna Maria Sadowska, Jordi Guillem-Marti, Montserrat Espanol, Christoph Stähli, Nicola Döbelin, Maria-Pau Ginebra
Biomaterials can interact with cells directly, that is, by direct contact of the cells with the material surface, or indirectly, through soluble species that can be released to or uptaken from the surrounding fluids. However, it is difficult to characterise the relevance of this fluid-mediated interaction separately from the topography and composition of the substrate, because they are coupled variables. These fluid-mediated interactions are amplified in the case of highly reactive CaPs such as biomimetic calcium deficient hydroxyapatite (CDHA), particularly in static in vitro cultures. The present work proposes a strategy to decouple the effect of ion exchange from topographical features by adjusting the volume ratio between the cell culture medium and biomaterial (VCM/VB). Increasing this ratio allowed mitigating the drastic ionic exchanges associated to the compositional changes experienced by the material exposed to the cell culture medium. This strategy was validated using rat mesenchymal stem cells (rMSCs) cultured on CDHA and beta-tricalcium phosphate (β-TCP) discs using different (VCM/VB) ratios. Whereas in the case of β-TCP the cell response was not affected by this ratio, a significant effect on cell adhesion and proliferation was found for the more reactive CDHA. The ionic exchange, produced by CDHA at low VCM/VB, altered cell adhesion due to the reduced number of focal adhesions, caused cell shrinkage and further rMCSs apoptosis. This was mitigated when using a high VCM/VB, which attenuated the changes of calcium and phosphate concentrations in the cell culture medium, resulting in rMSCs spreading and a viability over time. Moreover, rMSCs showed an earlier expression of osteogenic genes on CDHA compared to sintered β-TCP when extracellular calcium fluctuations were reduced.Statement of significanceFluid mediated interactions play a significant role in the bioactivity of calcium phosphates. Ionic exchange is amplified in the case of biomimetic hydroxyapatite, which makes the in vitro characterisation of cell-material interactions especially challenging. The present work proposes a novel and simple strategy to explore the mechanisms of interaction of biomimetic and sintered calcium phosphates with mesenchymal stem cells. The effects of topography and ion exchange are analysed separately by modifying the volume ratio between cell culture medium and biomaterial. High ionic fluctuations interfered in the maturation of focal adhesions, hampering cell adhesion and leading to increased apoptosis and reduced proliferation rate.
Graphical abstract
https://ift.tt/2lnPrYM
Titania coating of mesoporous silica nanoparticles for improved biocompatibility and drug release within blood vessels
Publication date: Available online 20 June 2018
Source:Acta Biomaterialia
Author(s): Asima Farooq, Ali Shukur, Cai Astley, Lubomira Tosheva, Peter Kelly, Debra Whitehead, May Azzawi
Blood vessel disease is a major contributor to cardiovascular morbidity and mortality and is hallmarked by dysfunction of the lining endothelial cells (ECs). These cells play a significant role in vascular homeostasis, through the release of mediators to control vessel diameter, hence tissue perfusion. Mesoporous silica nanoparticles (MSNs) can be used as potential drug delivery platforms for vasodilator drugs. Here, using an ex vivo model of vascular function, we examine the use of titania coating for improved biocompatibility and release dynamics of MSN loaded sodium nitroprusside (SNP). MSNs (95 ± 23 nm diameter; pore size 2.7 nm) were synthesised and fully characterised. They were loaded with SNP and coated with titania (TiO2), using the magnetron sputtering technique. Pre-constricted aortic vessels were exposed to drug loaded MSNs (at 1.96 x 1012 MSN mL-1) and the time course of vessel dilation observed, in real time. Exposure of viable vessels to MSNs lead to their internalization into the cytoplasm of ECs, while TiMSNs were also observed in the elastic lamina and smooth muscle cell layers. We demonstrate that titania coating of MSNs significantly improves their biocompatibility and alters the dynamics of drug release. A slow and more sustained relaxation was evident after uptake of TiMSN-SNP, in comparison to uncoated MSN-SNP (rate of dilation was 0.08% per min over a 2.5 h period). The use of titania coated MSNs for drug delivery to the vasculature may be an attractive strategy for therapeutic clinical intervention in cardiovascular disease.Statement of significanceCardiovascular disease is a major cause of mortality and morbidity worldwide, with a total global cost of over $918 billion, by 2030. Mesoporous silica nanoparticles (MSNs) have great potential for the delivery of drugs that can treat vessel disease. This paper provides the first description for the use of titania coated MSNs with increased vascular penetration, for the delivery of vasodilator drugs, without compromising overall vessel function. We demonstrate that titania coating of MSNs significantly improves their biocompatibility and uptake within aortic blood vessels and furthermore, enables a slower and more sustained release of the vasodilator drug, sodium nitroprusside within the vessel, thus making them an attractive strategy for the treatment of vascular disease.
Graphical abstract
https://ift.tt/2yrNT9k
Resident Vitality in 34 Programs at 14 Academic Health Systems: Insights for Educating Physicians and Surgeons for the Future
Publication date: Available online 19 June 2018
Source:Journal of Surgical Education
Author(s): Linda H. Pololi, Arthur T. Evans, Janet T. Civian, Sandy Shea, Robert T. Brennan
OBJECTIVETo clarify our understanding of how the culture of residency training influences the well-being of residents, this study reports on the vitality of residents at 34 programs across the United States and identifies characteristics of the programs, institutions and residents that are associated with high resident vitality.DESIGNIn 2014 to 2015, residents nationally were surveyed using the validated C - Change Resident Survey. The survey assessed residents' vitality and 12 other dimensions that characterize residents' perspectives of the culture of the residency training programs: Self-efficacy, Institutional/program support, Relationships/inclusion/trust, Values alignment, Ethical/moral distress, Respect, Leadership aspirations, Mentoring, Work-life integration, Gender equity, Racial/ethnic minority equity, and self-assessed Competencies. Multilevel models were used to assess vitality within and across programs, and examine predictors including resident, program, and institution characteristics.PARTICIPANTSTwo thousand four hundred and fifty-two residents from 11 General Surgery, 12 Internal Medicine, and 11 Pediatrics programs at 14 U.S. academic health systems.RESULTSOne thousand seven hundred and eight residents responded (70% response rate). The mean Vitality score was 3.6 (range 1–5, where values of 4–5 represent high Vitality). There was wide variation among the 34 programs in the percent of residents who had high Vitality scores, ranging from 17% to 71%. However, the average Vitality scores within specialty (Surgery, Medicine, and Pediatrics) were not significantly different. The strongest predictors of Vitality were Work-life integration, Relationships/inclusion/trust, Institutional/program support, Res?>pect, Values alignment, and Ethical/moral distress, which together accounted for 50% of vitality variance. Individual demographics accounted for just 3% of variance.CONCLUSIONSVitality is an essential component of resident well-being, and within each specialty there are programs that have excelled in promoting a culture of high vitality. Our findings suggest that we should test interventions to enhance resident vitality by focusing greater attention on providing institutional support, aligning individual and institutional values, integrating work and personal life, and facilitating relationships, inclusiveness and trust.
https://ift.tt/2K37jmo
Popularity of Online Multimedia Educational Resources in Neurosurgery: Insights from The Neurosurgical Atlas Project
Source:Journal of Surgical Education
Author(s): Benjamin Davidson, Naif M. Alotaibi, Benjamin K Hendricks, Aaron A. Cohen-Gadol
OBJECTIVEThe Neurosurgical Atlas is a popular world-wide multimedia website in neurosurgery with informative chapters and videos to promote excellence and safety in neurosurgical techniques. Here, we present our analysis of the viewing data of this website. This is intended to describe how online neurosurgical resources are being utilized by today's neurosurgical community. We hope this will be a useful guide for neurosurgeons interested in online multimedia education.DESIGN/SETTING/PARTICIPANTSWe analyzed Google Analytics and Vimeo data collected from The Neurosurgical Atlas between June 2016 and August 2017, which tracked user demographics, geographical location, and the videos watched. Views were also analyzed categorically by dividing videos into 6 neurosurgical topics and into basic and advanced levels as per their surgical complexity.RESULTSDuring the study period, there were 246,259 website visits and 143,868 video plays. The most frequent age group seen was 25 to 34 (44%), followed by 35 to 44 (24%), and 71% of visitors were male. Most website visits were from the United States (29.52%) followed by Brazil (6.43%). There was a steady increase in website visits and video plays over time, with multiple peaks corresponding to promotional email updates. The 6 neurosurgical topics were all similarly popular in video plays, with the general neurosurgical topics being slightly preferred. Similarly, basic and advanced topics were both viewed frequently, with a slight preference for the basic topics.CONCLUSIONSOur study presents the first piece of evidence demonstrating the feasibility and popularity of a free online resource in neurosurgical education. Our experience highlights the growing demand for free-access online chapters, anatomical illustrations, and operative videos. This initiative should not stop with The Neurosurgical Atlas; other surgeons should feel encouraged to employ similar methods to disseminate and advance surgical education.
https://ift.tt/2MGUe3Z
Plant community composition along a peatland margin follows alternate successional pathways after hydrologic disturbance
Source:Acta Oecologica, Volume 91
Author(s): Ellie M. Goud, Caitlin Watt, Tim R. Moore
Hydrological disturbances can alter the structure and function of ecosystems by changing plant species composition over time. Peatlands in the northern hemisphere are particularly sensitive to global change drivers related to soil water availability, such as drought and drainage, because of important ecohydrological feedbacks between species composition and water table position. Here, we examined the plant community structure and environmental drivers of species distributions over two growing seasons along a bog – margin gradient, pre- and post-disturbance by beaver activity. Pond drainage resulted in seasonal average water table depth 8–24 cm lower in the second season. Five plant communities corresponded to changes in water table depth and acidity: bog, poor fen, meadow, mudflat and pond. Plant cover increased in meadow and mudflat communities, decreased in the pond community and did not differ between years in bog and poor fen communities. Changes in species abundance between years showed signs of alternate successional pathways: one that favors Sphagnum moss and bog community expansion and another pathway that favors meadow and mudflat expansion. This study highlights the non-linear successional trajectory of plant communities with changes in water table depth, which has implications for land management goals that aim to conserve the ecological integrity of peatland ecosystems.
https://ift.tt/2ytOjMG
Elimination of melanoma by sortase A-generated TCR-like antibody-drug conjugates (TL-ADCs) targeting intracellular melanoma antigen MART-1
Source:Biomaterials, Volume 178
Author(s): Jun Lai, Yun Wang, Shan-Shan Wu, Ding Ding, Ze-Yu Sun, Ying Zhang, Jie Zhou, Zhan Zhou, Ying-Chun Xu, Li-Qiang Pan, Shu-Qing Chen
Most tumor-associated proteins are located inside tumor cells and thus are not accessible to current marketed therapeutic monoclonal antibodies or their cytotoxic conjugates. Human leukocyte antigen (HLA) class I can present peptides derived from intracellular tumor-associated proteins and somatically mutated proteins on the cell's surface, forming an HLA/peptide complex as tumor-specific antigens for T cell receptor (TCR) recognition. Therefore, HLA-mediated presentation of intracellular tumor antigen peptides provides a viable way to distinguish tumor cells from normal cells, which is important for broadening antigen selection, especially for antibody-drug conjugates (ADCs) regarding their highly cytotoxic payload. We applied sortase A-mediated conjugation to develop TCR-like ADCs (i.e., EA1 HL-vcMMAE) targeting intracellular MART-1 protein, a melanocyte-differentiating antigen specific for metastatic melanomas, via the cell surface HLA-A2/MART-126-35 peptide complex. Homogenous EA1 HL-vcMMAE (drug to antibody ratio of 4) efficiently eliminated melanoma cells in xenograft mouse models with no obvious toxicity at the therapeutic dosage. Trametinib, an MEK inhibitor serving as an HLA expression enhancing agent, augmented the TL-ADCs' efficacy both in vitro and in vivo by upregulating MART-126-35 peptide presentation, thus providing a strategy for overcoming the limitation of antigen presentation level for TL-ADCs. Hence, our findings validate the strategy of using sortase A-generated TL-ADCs to target tumor-specific intracellular proteins, with or without agents present, to increase presenting TCR epitope peptides.
https://ift.tt/2JWdBbH
Construction of humanized anti-HER2 single-chain variable fragments (husFvs) and achievement of potent tumor suppression with the reconstituted husFv-Fdt-tBid immunoapoptotin
Source:Biomaterials, Volume 178
Author(s): Qing Ou-Yang, Bo Yan, Ang Li, Zhi-Song Hu, Jian-Nan Feng, Xin-Xin Lun, Ming-Ming Zhang, Meng-De Zhang, Kai-Chun Wu, Fang-Fang Xue, An-Gang Yang, Jing Zhao
As HER2 is frequently overexpressed in various malignancies, targeting HER2 is considered an efficient, highly selective antitumor therapy. HER2-targeted immunoconjugates are being developed and result in persistent remission of HER2-overexpressing tumors. However, many of the antibodies used as the targeting moiety are of murine origin and exhibit risk of inducing immunogenicity, limiting their antitumor therapeutic efficacy. Here, we humanized e23sFv, an HER2-targeting murine scFv with excellent affinity and specificity, using a human antibody consensus sequence engraftment strategy. The affinity of the initially humanized e23sFv was then rescued and improved by selective mutagenesis followed by phage-display-based affinity panning of the mutant pool. The resulting humanized e23sFv candidates (husFvs) exhibited up-to-94-fold increased affinity to recombinant HER2. The immunogenicity of e23sFv was dramatically alleviated after humanization, as indicated by the impaired production of cytokines by husFv-stimulated human PBMCs. Two internalizable husFvs with optimal affinity were applied to generate humanized immunoapoptotins by infusion with the translocation domain Fdt and the proapoptotic domain truncated Bid. The husFv-immunoapoptotins demonstrated improved HER2-targeting and tumor-killing capacities in vitro and in vivo compared with the e23sFv-immunoapoptotins and would enable the administration of multiple treatment cycles to patients, resulting in improved antitumor efficacy. Furthermore, the husFvs recognized distinct HER2 epitopes and could thus be used in combination with trastuzumab or pertuzumab to achieve robust synergistic antitumor effects in HER2-positive malignancies.
https://ift.tt/2M7K3UY
Scholar : Canadian Water Resources Journal / Revue canadienne des ressources hydriques, Volume 43, Issue 2, June 2018 is now available online on Taylor & Francis Online
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Top-down characterization of chicken core histones
Publication date: Available online 20 June 2018
Source:Journal of Proteomics
Author(s): Hao Wu, Kaijie Xiao, Zhixin Tian
Core histones and their PTMs play important roles in regulating gene transcription and other DNA-related processes. The study of core histones PTMs, their cross-talk and functional roles is not only of broad biological significance but also of wide pathological and clinical relevance. Having the strength of comprehensive proteoform identification with 100% amino acid sequence coverage and combinatorial PTMs, top-down proteomics has become the state-of-the-art analytical tool for combinatorial PTM characterization of core histones. In this study, we report our top-down characterization of chicken (Gallus gallus domesticus) core histones, which have been widely used as models for chromosome re-construction among others because of easy availability and not-so-dense PTMs. With nanoRPLC-MS/MS analysis and ProteinGoggle database search, a total of 58 proteoforms were identified for the core histone families of H4, H2B, H2A, and H3.
Graphical abstract
https://ift.tt/2K1OsIs
Global analysis of ubiquitome in PRRSV-infected pulmonary alveolar macrophages
Publication date: Available online 19 June 2018
Source:Journal of Proteomics
Author(s): Huan Zhang, Liurong Fang, Xinyu Zhu, Dang Wang, Shaobo Xiao
Protein lysine ubiquitination is a dynamic reversible post-translational modification that plays key roles in modulating different cellular processes. Porcine reproductive and respiratory syndrome virus (PRRSV) is a notorious pathogen, causing tremendous economic losses for the global swine industry. The possible involvement of ubiquitination in PRRSV infection is unclear. So anti-ubiquitination-based enrichment and LC-MS were performed to investigate the global ubiquitination events triggered by PRRSV infection in pulmonary alveolar macrophages. We totally identified 4044 lysine ubiquitination sites on 1580 cellular proteins, of which 983 sites on 717 proteins were significantly altered at 36 h postinfection. A systematic, intensive bioinformatic analysis of the ubiquitome data suggested that PRRSV suppresses the host immune responses by manipulating the ubiquitination of important adaptors and effectors, including TRAF6, JAK1, STAT1, and ISGs. Ubiquitination was also observed on 15 PRRSV proteins, including important virus proteases and structural proteins that function in virus infectivity and neutralizing antibody elicitation. The efficient replication of PRRSV requires an intact ubiquitin–proteasome system. Our study is the first to analyze the global ubiquitination events in pulmonary alveolar macrophages during PRRSV infection. It provides insight into the molecular mechanisms of PRRSV pathogenesis, promoting the development of antiviral drugs.Biological significancePRRSV is a notorious pathogen which has been resulting in huge economic losses in the swine industry since the first outbreak. Therefore, more in-depth knowledge of the PRRSV immunoregulatory mechanisms and valid control methods to combat the virus are urgently needed. Ubiquitination is an important post-translational modification regulating various cellular processes. However, information about the possible involvement of ubiquitination responses to PRRSV infection is limited. In this study, a quantitative proteomic approach was first used to analyze ubiquitination level alteration in PRRSV-infected PAMs. We demonstrate that PRRSV can suppresses the host immune responses by manipulating the ubiquitination of important effectors that include TRAF6, JAK1, STAT1, and ISGs. Furthermore, 15 PRRSV proteins undergo ubiquitination and efficient replication of PRRSV requires an intact ubiquitin–proteasome system. Our study will significantly expand our knowledge about the molecular mechanisms of PRRSV pathogenesis and provides novel insights into the development of antiviral drugs.
Graphical abstract
https://ift.tt/2JTrAim
Combination of the fetal urinary metabolome and peptidome for the prediction of postnatal renal outcome in fetuses with PUV
Publication date: Available online 19 June 2018
Source:Journal of Proteomics
Author(s): Bénédicte Buffin-Meyer, Julie Klein, Benjamin Breuil, Françoise Muller, Panagiotis Moulos, Marion Groussolles, Ourdia Bouali, Jean-Loup Bascands, Stéphane Decramer, Joost P. Schanstra
Most of biomarker panels, extracted from single omics traits, still need improvement since they display a gray zone where prediction is uncertain. Here we verified whether a combination of omics traits, fetal urinary metabolites and peptides analyzed in the same sample, improved prediction of postnatal renal function in fetuses with posterior urethral valves (PUV) compared to individual omics traits.Using CE-MS, we explored the urinary metabolome of 13 PUV fetuses with end stage renal disease (ESRD) and 12 PUV fetuses without postnatal ESRD at 2 years postnatally. This allowed the selection of 24 differentially abundant metabolite features which were modelled into predictive classifiers, alone or in combination with 12 peptides previously identified as predictive of ESRD. Validation in 35 new fetuses showed that the combination of peptides and metabolites significantly outperformed the 24 metabolite features with increased AUC (0.987 vs 0.905), net reclassification improvement (36%) and better sensitivity accuracy (86% vs 60%). In addition, the two trait combination tended to improve, but without reaching statistical significance, the already high performances of the 12 peptide biomarkers (AUC 0.967, accuracy 80%).In conclusion, this study demonstrates the potential of cumulating different omics traits in biomarker research where single omics traits fall short.SignificanceAlthough increasingly proposed in disease-diagnosis and -prognosis because of their improved efficacy over single markers, panels of body fluid biomarkers based on single omics analysis still fail to display perfect accuracy, probably due to biological variability.Here, we hypothesized that combination of different omics traits allowed to better capture this biological variability. As proof of concept, we studied the added value of fetal urine metabolites and peptides using CE-MS, starting from the same urine sample, to predict postnatal renal outcome in fetuses with posterior urethral valves. We observed that the prognostic power of combined metabolite and peptide markers was clearly higher than that of metabolites alone and slightly, but non-significantly, improved compared to the peptides alone. To our knowledge, this report is the first to demonstrate that combining multiomics traits extracted from (fetal) urine samples displays clear promise for kidney disease stratification.
Graphical abstract
https://ift.tt/2M6VPyJ
Progesterone Resistance in Endometriosis: an Acquired Property?
Publication date: Available online 19 June 2018
Source:Trends in Endocrinology & Metabolism
Author(s): Brett McKinnon, Michael Mueller, Grant Montgomery
Endometriosis is the growth of endometrial tissue outside the uterus and is characterized by progesterone resistance and changes in global and progesterone target gene expression. However, the mechanism behind this and whether it is innate, acquired, or present in both the eutopic and ectopic tissue in not always clear. We find large-scale gene expression studies in eutopic tissue, indicative of progesterone resistance, are often contradictory, potentially due to the dynamic nature of this tissue, whereas suppressed progesterone receptor expression is supported in ectopic but not eutopic tissue. This suggests more studies are required in eutopic tissue particularly, and that potentially the suppressed progesterone receptor (PR) expression is a consequence of the pathogenic process and exposure to the peritoneal environment.
https://ift.tt/2I5rIWh
Scholar : These new articles for Alcheringa: An Australasian Journal of Palaeontology are available online
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CAD-FEA modeling and analysis of different full crown monolithic restorations
Source:Dental Materials
Author(s): Amanda Maria de Oliveira Dal Piva, João Paulo Mendes Tribst, Alexandre Luiz Souto Borges, Rodrigo Othávio de Assunção e Souza, Marco Antonio Bottino
ObjectivesTo investigate the influence of different materials for monolithic full posterior crowns using 3D-Finite Element Analysis (FEA).MethodsTwelve (12) 3D models of adhesively-restored teeth with different crowns according to the material and its elastic modulus were analysed: Acrylic resin, Polyetheretherketone, Composite resin, Hybrid ceramic, pressable and machinable Zirconia reinforced lithium silicate, Feldspathic, Lithium disilicate, Gold alloy, Cobalt–Chromium alloy (Co–Cr), Zirconia tetragonal partially stabilized with yttria, and Alumina. All materials were assumed to behave elastically throughout the entire deformation. Results in restoration and cementing line were obtained using maximum principal stress. In addition, maximum shear stress criteria was used for the cementing line.ResultsRestorative materials with higher elastic modulus present higher stress concentration inside the crown, mainly tensile stress on an intaglio surface. On the other hand, materials with lower elastic modulus allow stress passage for cement, increasing shear stress on this layer. Stiffer materials promote higher stress peak values.SignificanceMaterials with higher elastic modulus such as Co–Cr, zirconia and alumina enable higher tensile stress concentration on the crown intaglio surface and higher shear stress on the cement layer, facilitating crown debonding.
https://ift.tt/2MFTyeY
Effect of thiourethane filler surface functionalization on stress, conversion and mechanical properties of restorative dental composites
Source:Dental Materials
Author(s): André L. Faria-e-Silva, Andressa dos Santos, Angela Tang, Emerson M. Girotto, Carmem S. Pfeifer
ObjectivesThis study evaluated the efficacy of a thiourethane(TU)-modified silane agent in improving properties in filled composites.MethodsThe TU-silane agent was synthesized by combining 1,3-bis(1-isocyanato-1-methylethyl)benzene and 3-(triethoxysilyl)propyl isocyanate with trimethylol-tris-3-mercaptopropionate (TMP), at 1:2 isocyanate:thiol, leaving pendant thiol and alkoxy silane groups. Barium glass fillers (1μm average particle size) were functionalized with 5wt% TU-silane in an acidic ethanol solution. Commercially available 3-(trimethoxysilyl)propyl methacrylate (MA-silane) and (3-mercaptopropyl)trimethoxysilane (SH-silane), as well as no silane treatment (NO-silane), were used as controls. Composites were made with BisGMA-UDMA-TEGDMA (5:3:2), camphorquinone/ethyl-4-dimethylaminobenzoate (0.2/0.8wt%) and di-tert-butyl hydroxytoluene (0.3wt%) and 70wt% silanated inorganic fillers. Polymerization stress (PS) was measured using a cantilever beam apparatus (Bioman). Methacrylate conversion (DC) and rate of polymerization (RP) during photoactivation (800mW/cm2) were followed in real-time with near-IR. Flexural strength/modulus (FS/FM) were evaluated in three-point bending with 2×2×25 mm. Statistical analysis: 2-way ANOVA/Tukey's test (α=5%).ResultsDC, Rpmax and E were similar for all groups tested. FS was similar for the TU- and MA-silane, which were statistically higher than the untreated and SH-silane groups. Stress reductions in relation to the MA-silane were observed for all groups, but statistically more markedly for the TU-silane material. This is likely due to stress relaxation and/or toughening provided at the filler interface by the oligomeric TU structure.SignificanceTU-silane oligomers favorably modified conventional dimethacrylate networks with minimal disruption to existing curing chemistry, in filled composites. For the same conversion values, stress reductions of up to 50% were observed, without compromise to mechanical properties or handling characteristics.
https://ift.tt/2ypt1Qj
Fatigue behavior of ultrafine tabletop ceramic restorations
Source:Dental Materials
Author(s): F.O. Abu-Izze, G.F. Ramos, A.L.S. Borges, L.C. Anami, M.A. Bottino
ObjectiveThe goal of this study was to investigate the fatigue life, failure modes, and stress distribution of partial ultrafine restorations for posterior teeth in different ceramics.MethodsSixty standard tabletop preparations in epoxy resin G10 received lithium-silicate-based zirconia-reinforced (ZLS) or hybrid ceramic (PIC) restorations in 0.5- or 1-mm thickness bonded with resin cement. The same cycling protocol was applied for all specimens, which consisted of 5000 cycles at 200N, followed by 450-N cycles until the specimens' fracture or the suspension of the test after 1.5×106 cycles. Axial load was carried out with a 4Hz frequency in Biocycle V2 equipment (Biopdi, São Carlos, SP), with samples immersed in water. The presence of cracks and/or fractures was checked every 2.5×105 cycles, and the survival analysis was performed with the number of cycles in which each specimen failed. All specimens were evaluated by stereomicroscopy and scanning electron microscopy (SEM). After data tabulation, Kaplan–Meier and Mantel–Cox (log-rank test) analyses were performed, followed by multiple pairwise comparison, all with a significance level of 5%, and Weibull analysis. Through three-dimensional finite element analysis, stress distribution and maximum principal stresses in the posterior occlusal veneers were evaluated by comparison of different types of substrate (G10, enamel/dentin, enamel), thicknesses, and ceramic materials.ResultsZirconium-reinforced lithium silicate restorations with 0.5-mm thickness (ZLS.5) showed lower fatigue strength compared with that of 1.0-mm hybrid ceramic restorations (PIC1), and both were similar to other restorations (PIC.5 and ZLS1) (log-rank test, χ2=11.2; df=3; p=0.0107<0.05). ZLS groups presented random defects that culminated in fracture, whereas PIC groups presented defects that increased with mechanical fatigue after some cycling time. Stereomicroscope images show radial cracks due to the translucency of the material. There was no damage caused by the applicator. MPS (maximum principal stress) distributions were similar for the different substrate types, but the highest modulus of elasticity showed slightly lower stress concentration.SignificancePIC is more likely to be used in thinner thickness than indicated by the manufacturer, with fatigue strength similar to that of thicker ZLS restorations.
https://ift.tt/2tcnjfB
Comparative Effects of Topical 0.2% Sirolimus for Angiofibromas in Adults and Pediatric Patients with Tuberous Sclerosis Complex
Dermatology
https://ift.tt/2K2SFPr
Understanding Health-related Quality of Life in Caregivers of Civilians and Service Members/Veterans with Traumatic Brain Injury: Establishing the Reliability and Validity of PROMIS Mental Health Measures
Publication date: Available online 19 June 2018
Source:Archives of Physical Medicine and Rehabilitation
Author(s): Noelle E. Carlozzi, Robin Hanks, Rael T. Lange, Tracey A. Brickell D.Psych, Phillip A. Ianni, Jennifer A. Miner, Louis M. French Psy.D., Michael A. Kallen, Angelle M. Sander
ObjectiveTo provide important reliability and validity data to support the use of the PROMIS Mental Health measures in caregivers of civilians or service members/veterans with traumatic brain injury (TBI).DesignPatient-reported outcomes surveys administered through an electronic data collection platform.SettingThree TBI Model Systems rehabilitation hospitals, an academic medical center, and a military medical treatment facility.Participants560 caregivers of individuals with a documented TBI (344 civilians and 216 military)InterventionNot ApplicableMain Outcome MeasuresPROMIS Anxiety, Depression, and Anger Item BanksResultsInternal consistency for all of the PROMIS Mental Health item banks was very good (all α > .86) and three-week test retest reliability was good to adequate (ranged from .65 to .85). Convergent validity and discriminant validity of the PROMIS measures was also supported. Caregivers of individuals that were low functioning had worse emotional HRQOL (as measured by the three PROMIS measures) than caregivers of high functioning individuals, supporting known groups validity. Finally, levels of distress, as measured by the PROMIS measures, were elevated for those caring for low-functioning individuals in both samples (rates ranged from 26.2% to 43.6% for caregivers of low-functioning individuals).ConclusionsResults support the reliability and validity of the PROMIS Anxiety, Depression, and Anger item banks in caregivers of civilians and service members/veterans with TBI. Ultimately, these measures can be used to provide a standardized assessment of HRQOL as it relates to mental health in these caregivers.
https://ift.tt/2I9FcAo
Understanding health-related quality of life in caregivers of civilians and service members/veterans with traumatic brain injury: Establishing the reliability and validity of PROMIS Fatigue and Sleep Disturbance item banks
Publication date: Available online 20 June 2018
Source:Archives of Physical Medicine and Rehabilitation
Author(s): Noelle E. Carlozzi, Phillip A. Ianni, David S. Tulsky, Tracey A. Brickell, Rael T. Lange, Louis M. French, David Cella, Michael A. Kallen, Jennifer A. Miner, Anna L. Kratz
ObjectiveTo examine the reliability and validity of Patient Reported Outcomes Measurement Information System (PROMIS) measures of sleep disturbance and fatigue in TBI caregivers and to determine the severity of fatigue and sleep disturbance in these caregivers.DesignCross-sectional survey data collected through an online data capture platform.SettingFour rehabilitation hospitals and Walter Reed National Military Medical Center.ParticipantsCaregivers (N=560) of civilians (n=344) and service member/veterans (n=216) with TBI.InterventionNot ApplicableMain Outcome MeasuresPROMIS sleep and fatigue measures administered as both computerized adaptive tests (CATs) and 4-item short forms (SFs).ResultsFor both samples, floor and ceiling effects for the PROMIS measures were low (<11%), internal consistency was very good (all alphas ≥0.80), and test-retest reliability was acceptable (all r≥0.70 except for the fatigue CAT in the service member/veteran sample r=0.63). Convergent validity was supported by moderate correlations between the PROMIS and related measures. Discriminant validity was supported by low correlations between PROMIS measures and measures of dissimilar constructs. PROMIS scores indicated significantly worse sleep and fatigue for those caring for someone with high levels versus low levels of impairment.ConclusionsFindings support the reliability and validity of the PROMIS CAT and SF measures of sleep disturbance and fatigue in caregivers of civilians and service members/veterans with TBI.
https://ift.tt/2K78Jj2
Photoresponsive polymeric carbon nitride-based materials: Design and application
Publication date: Available online 19 June 2018
Source:Materials Today
Author(s): Hui Wang, Xiaodong Zhang, Yi Xie
Recently polymeric carbon nitride-based materials have attracted tremendous attention for their outstanding photoresponsive properties, promising their great potential in various photoexcitation-related applications such as photocatalysis, photoelectrochemistry, photoluminescence, etc. On the basis of the understanding of the photoexcitation processes and structural features in the intriguing polymeric system, enormous efforts have been devoted to the optimization of photoresponsive performance via structure engineering, leaving various strategies for gaining efficient photoresponsive applications. In this review, we summarize recent advances in the exploitation of photoresponsive polymeric carbon nitride-based materials, highlighting the unique photoexcitation processes involved therein. We review the universal optimization strategies for the design of advanced photoresponsive materials, providing insights into the relationships between structural factors and photoexcitation processes in polymeric carbon nitride-based materials. Then photoresponsive applications and the involved functional mechanisms of polymeric carbon nitride-based materials are discussed. We conclude the review with a brief discussion of the future challenges and opportunities for the developments of polymeric carbon nitride-based materials.
Graphical abstract
https://ift.tt/2I74nmP
The emerging role of circRNAs and their clinical significance in human cancers
Publication date: Available online 19 June 2018
Source:Biochimica et Biophysica Acta (BBA) - Reviews on Cancer
Author(s): Ling Qian, Shulin Yu, Zhen Chen, Zhiqiang Meng, Shenglin Huang, Peng Wang
Circular RNA (circRNA), a recently discovered subclass of non-coding RNAs (ncRNAs), forms a covalently closed loop with neither a 5′ cap structure nor a 3′ polyadenylated tail. Generated from precursor mRNA (pre-mRNA) through "backsplicing" (a type of alternative RNA splicing), the majority of circRNAs are located in the cytoplasm and are widespread among living organisms. They are stable and conserved and exhibit spatiotemporal-specific expression. circRNAs are known to be involved in the development and progression of multiple diseases, including cancer, by acting as microRNA (miRNA) sponges and by regulating processes such as transcription and translation. The extensively aberrant expression profiles of circRNAs in multiple cancerous tissues make these molecules promising diagnostic biomarkers and therapeutic targets for cancer. Here, we briefly review the characteristics, biogenesis, classification, and functions of circRNAs, with a particular focus on the role of circRNAs in various cancers.
https://ift.tt/2I7h0OJ
Muscle-Tendon Mechanics During Locomotor Tasks, Efficacy of Collagen Supplementation for Older Adults
Interventions: Dietary Supplement: Collagen supplement group; Dietary Supplement: Placebo supplement group
Sponsor: Liverpool John Moores University
Not yet recruiting
https://ift.tt/2tmLmYk
Acute Hospital Encounters in Cancer Patients Treated With Definitive Radiation Therapy
Source:International Journal of Radiation Oncology*Biology*Physics, Volume 101, Issue 4
Author(s): Mallika Marar, Peter Gabriel, Wei-Ting Hwang, Daniel R. Owen, Melody Ju, Charles B. Simone, John Christodouleas, Neha Vapiwala, Abigail T. Berman
PurposeAcute hospital encounters in patients undergoing curative-intent radiation therapy (RT) have not previously been well characterized. Understanding acute visit patterns among RT patients yields insights for risk assessments and cancer urgent care clinics that could decrease hospitalization rates and reduce health care costs. This study aims to identify patient, disease-site, and treatment characteristics associated with emergency department visits and inpatient admissions in cancer patients treated with definitive RT.Methods and MaterialsA retrospective cohort study was conducted using data from a quaternary-care cancer center. The cohort was defined as all consecutive patients aged ≥ 18 years who began RT between July 1, 2011, and December 31, 2013; were without metastases; and were treated with curative intent. An acute encounter was defined as an emergency department visit or inpatient admission during RT or within 30 days after the conclusion of RT.ResultsAmong 1852 unique RT courses, 666 RT courses (36.0%) involved at least 1 acute encounter, and a total of 1418 acute encounters were identified. RT courses with at least 1 acute encounter corresponded to patients more likely to be on their second (odds ratio [OR], 1.96; P < .001) or third (OR, 3.82; P < .05) RT course and undergoing concurrent chemotherapy (OR, 6.38; P < .001). Among the RT courses with at least 1 acute encounter, the most common disease site was thoracic (22.8%), followed by head and/or neck (22.2%) and gastrointestinal (18.3%). Central nervous system tumors had the greatest proportion of RT courses with acute encounters (77.1%).ConclusionsIn this retrospective analysis, more than one-third of curative-intent RT courses were associated with at least 1 acute hospital encounter during or shortly after irradiation. Given that acute encounters varied by patient, disease-site, and treatment characteristics, these findings can inform targeted preventive measures to reduce cancer-related acute hospital encounters and guide improved management protocols.
https://ift.tt/2ljWZeZ
Do Existing Audiometric Dose-Effect Models and Risk Factors Apply to Children Treated With Proton Therapy?
Source:International Journal of Radiation Oncology*Biology*Physics, Volume 101, Issue 4
Author(s): Babita Jyoti, Ronny L. Rotondo, Julie A. Bradley, Christopher G. Morris, Daniel J. Indelicato
https://ift.tt/2tmR50d
GI Cancers—Modulating the Modern Management of Gastrointestinal Malignancies: A Look at Liver Metastases, Rectal Cancer, Esophagogastric Cancer, and Anal Cancer
Source:International Journal of Radiation Oncology*Biology*Physics, Volume 101, Issue 4
Author(s): Salma K. Jabbour, Smith Apisarnthanarax, Christopher L. Hallemeier, Florence Huguet, James D. Murphy, Jeffrey R. Olsen
https://ift.tt/2lnqf4F
In Regard to Palmer et al
Source:International Journal of Radiation Oncology*Biology*Physics, Volume 101, Issue 4
Author(s): Shearwood McClelland, Jerry J. Jaboin
https://ift.tt/2tnKy5n
In the Eye of the Maximal Storm: Surgery Versus Radiation?
Source:International Journal of Radiation Oncology*Biology*Physics, Volume 101, Issue 4
Author(s): James Janopaul-Naylor, Sue S. Yom
https://ift.tt/2llpZ64
Reluctant Induction Followed by Proton Beam Therapy, If Practicable
Source:International Journal of Radiation Oncology*Biology*Physics, Volume 101, Issue 4
Author(s): Minh Tam Truong, Gregory Grillone
https://ift.tt/2yrmeW3
Organ Preservation in Sinonasal Malignancies Through Particle Therapy
Source:International Journal of Radiation Oncology*Biology*Physics, Volume 101, Issue 4
Author(s): Alexandra D. Jensen
https://ift.tt/2ln3626
Erratum to: Mohan R, Held KD, Story MD, et al. Proceedings of the National Cancer Institute Workshop on Charged Particle Radiobiology. Int J Radiat Oncol Biol Phys 2018;100:816-831.
Source:International Journal of Radiation Oncology*Biology*Physics, Volume 101, Issue 4
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Time to Rethink Our Strategy With a Preoperative Intensification Approach
Source:International Journal of Radiation Oncology*Biology*Physics, Volume 101, Issue 4
Author(s): Nabil F. Saba
https://ift.tt/2lk5XZN
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Publication date: September 2017 Source: Free Radical Biology and Medicine, Volume 110 Author(s): Lucía Fernández-del-Río, Anish Nag, Elen...
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Abstract Noise pollution is a major factor of environmental complaints in many cities, which has significant impacts on human health. As a...
