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31.
Laura Noël-Romas Michelle Perner Refilwe Molatlhegi Christina Farr Zuend Amanda Mabhula Sarah Hoger Alana Lamont Kenzie Birse Alicia Berard Stuart McCorrister Garett Westmacott Al Leslie Vanessa Poliquin Renee Heffron Lyle R. McKinnon Adam D. Burgener 《PLoS pathogens》2020,16(12)
Alterations to the mucosal environment of the female genital tract, such as genital inflammation, have been associated with increased HIV acquisition in women. As the microbiome and hormonal contraceptives can affect vaginal mucosal immunity, we hypothesized these components may interact in the context of HIV susceptibility. Using previously published microbiome data from 685 women in the CAPRISA-004 trial, we compared relative risk of HIV acquisition in this cohort who were using injectable depot medroxyprogesterone acetate (DMPA), norethisterone enanthate (NET-EN), and combined oral contraceptives (COC). In women who were Lactobacillus-dominant, HIV acquisition was 3-fold higher in women using DMPA relative to women using NET-EN or COC (OR: 3.27; 95% CI: 1.24–11.24, P = 0.0305). This was not observed in non-Lactobacillus-dominant women (OR: 0.95, 95% CI: 0.44–2.15, P = 0.895) (interaction P = 0.0686). Higher serum MPA levels associated with increased molecular pathways of inflammation in the vaginal mucosal fluid of Lactobacillus-dominant women, but no differences were seen in non-Lactobacillus dominant women. This study provides data suggesting an interaction between the microbiome, hormonal contraceptives, and HIV susceptibility. 相似文献
32.
Yi Liu Michael J. Trnka Shenheng Guan Doyoung Kwon Do-Hyung Kim J.-J. Chen Peter A. Greer A. L. Burlingame Maria Almira Correia 《Molecular & cellular proteomics : MCP》2020,19(12):1968-1986
Highlights
- •Liver Mallory-Denk-Body inducers elicited an IκBα-loss and NF-κB-activation.
- •IκBα-loss was due to its sequestration into insoluble cytoplasmic aggregates.
- •Four proteomic approaches identified 10 IκBα-interacting/aggregating proteins.
- •Nup153/RanBP2-aggregation prevented IκBα nuclear entry for ending NF-κB-activation.
33.
Shan Gao Michaela C. Strüder‐Kypke Khaled A. S. Al‐Rasheid Xiaofeng Lin Weibo Song 《Zoologica scripta》2010,39(3):305-313
Gao, S., Strüder‐Kypke, M.C., Al‐Rasheid, K.A.S., Lin, X. & Song, W. (2010). Molecular phylogeny of three ambiguous ciliate genera: Kentrophoros, Trachelolophos and Trachelotractus (Alveolata, Ciliophora).—Zoologica Scripta, 39, 305–313. Very few molecular studies on the phylogeny of the karyorelictean ciliates have been carried out because data of this highly ambiguous group are extremely scarce. In the present study, we sequenced the small subunit ribosomal RNA genes of three morphospecies representing two karyorelictean genera, Kentrophoros, Trachelolophos, and one haptorid, Trachelotractus, isolated from the South and East China Seas. The phylogenetic trees constructed using Bayesian inference, maximum likelihood, maximum parsimony and neighbor‐joining methods yielded essentially similar topologies. The class Karyorelictea is depicted as a monophyletic clade, closely related to the class Heterotrichea. The generic concept of the family Trachelocercidae is confirmed by the clustering of Trachelolophos and Tracheloraphis with high bootstrap support; nevertheless, the order Loxodida is paraphyletic. The transfer of the morphotype Trachelocerca entzi Kahl, 1927 to the class Litostomatea and into the new haptorid genus Trachelotractus, as suggested by previous researchers based on morphological studies, is consistently supported by our molecular analyses. In addition, the poorly known species Parduczia orbis occupies a well‐supported position basal to the Geleia clade, justifying the separation of these genera from one another. 相似文献
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35.
Marko Jot Benjamin Lipovek Botjan Glaar Amran Al‐Ashouri Kristijan Brecl Gaper Mati
Artiom Magomedov Vytautas Getautis Marko Topi
Steve Albrecht 《Liver Transplantation》2020,10(25)
Perovskite solar cells (PSC) have shown that under laboratory conditions they can compete with established photovoltaic technologies. However, controlled laboratory measurements usually performed do not fully resemble operational conditions and field testing outdoors, with day‐night cycles, changing irradiance and temperature. In this contribution, the performance of PSCs in the rooftop field test, exposed to real weather conditions is evaluated. The 1 cm2 single‐junction devices, with an initial average power conversion efficiency of 18.5% are tracked outdoors in maximum power point over several weeks. In parallel, irradiance and air temperature are recorded, allowing us to correlate outside factors with generated power. To get more insight into outdoor device performance, a comprehensive set of laboratory measurements under different light intensities (10% to 120% of AM1.5) and temperatures is performed. From these results, a low power temperature coefficient of ?0.17% K?1 is extracted in the temperature range between 25 and 85 °C. By incorporating these temperature‐ and light‐dependent PV parameters into the energy yield model, it is possible to correctly predict the generated energy of the devices, thus validating the energy yield model. In addition, degradation of the tested devices can be tracked precisely from the difference between measured and modelled power. 相似文献
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38.
Mahasweta Saha Francisco R. Barboza Paul J. Somerfield Balsam Al‐Janabi Miriam Beck Janina Brakel Maysa Ito Christian Pansch Jennifer C. Nascimento‐Schulze Stina Jakobsson Thor Florian Weinberger Yvonne Sawall 《Global Change Biology》2020,26(2):417-430
Marine heatwaves have been observed worldwide and are expected to increase in both frequency and intensity due to climate change. Such events may cause ecosystem reconfigurations arising from species range contraction or redistribution, with ecological, economic and social implications. Macrophytes such as the brown seaweed Fucus vesiculosus and the seagrass Zostera marina are foundation species in many coastal ecosystems of the temperate northern hemisphere. Hence, their response to extreme events can potentially determine the fate of associated ecosystems. Macrophyte functioning is intimately linked to the maintenance of photosynthesis, growth and reproduction, and resistance against pathogens, epibionts and grazers. We investigated morphological, physiological, pathological and chemical defence responses of western Baltic Sea F. vesiculosus and Z. marina populations to simulated near‐natural marine heatwaves. Along with (a) the control, which constituted no heatwave but natural stochastic temperature variability (0HW), two treatments were applied: (b) two late‐spring heatwaves (June, July) followed by a summer heatwave (August; 3HW) and (c) a summer heatwave only (1HW). The 3HW treatment was applied to test whether preconditioning events can modulate the potential sensitivity to the summer heatwave. Despite the variety of responses measured in both species, only Z. marina growth was impaired by the accumulative heat stress imposed by the 3HW treatment. Photosynthetic rate, however, remained high after the last heatwave indicating potential for recovery. Only epibacterial abundance was significantly affected in F. vesiculosus. Hence both macrophytes, and in particular F. vesiculosus, seem to be fairly tolerant to short‐term marine heatwaves at least at the intensities applied in this experiment (up to 5°C above mean temperature over a period of 9 days). This may partly be due to the fact that F. vesiculosus grows in a highly variable environment, and may have a high phenotypic plasticity. 相似文献
39.
Abdullah Al Emran Hsin‐Yi Tseng Mikaela C. Coleman Jessamy Tiffen Stuart Cook Helen M. McGuire Stuart Gallagher Carl Feng Peter Hersey 《Pigment cell & melanoma research》2020,33(5):660-670
Melanoma, as for many other cancers, undergoes a selection process during progression that limits many innate and adaptive tumor control mechanisms. Immunotherapy with immune checkpoint blockade overcomes one of the escape mechanisms but if the tumor is not eliminated other escape mechanisms evolve that require new approaches for tumor control. Some of the innate mechanisms that have evolved against infections with microorganisms and viruses are proving to be active against cancer cells but require better understanding of how they are activated and what inhibitory mechanisms may need to be targeted. This is particularly so for inflammasomes which have evolved against many different organisms and which recruit a number of cytotoxic mechanisms that remain poorly understood. Equally important is understanding of where these mechanisms will fit into existing treatment strategies and whether existing strategies already involve the innate killing mechanisms. 相似文献
40.
Noura Hamed Khalifa Al Shaqsi Horiya Ali Said Al Hoqani Mohammad Amzad Hossain Mohammed Abdullah Al Sibani 《Biochemistry and Biophysics Reports》2020
Chitin is an organic polymer and it is the most frequent marine natural polysaccharide after cellulose. The main natural sources of chitin are exoskeletons of insects, mollusks, the cell walls of certain fungi and crustaceans such as crabs, shrimps and lobsters. The waste of these marine exoskeletons are pollutant for the environment, but these waste raw materials could be useful for production of commercial products like chitin. Chitin is an important raw material used for water treatment, agricultural, biomedical, biotechnological purposes, food and paper industry and cosmetics. Based on the variety of importance, the present targets of this study are to optimize the demineralization process for the removal of calcium and phosphate contents from the waste of Portunidae segnis (P. segnis) by using acid at ambient temperature and to characterize the isolated demineralized sample as well as the percentage of remaining calcium and phosphorus contents by using Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES). The prepared waste carbs coarse powder samples of P. segnis were demineralized with seven different concentrations of hydrochloric acid at ambient temperature for 1 h. All the demineralization samples by the different concentrations were analyzed by using sensitive ICP-OES. The results based on ICP-OES showed that among the seven different concentrations used in the demineralization process for the isolation of chitin, the best was 2 M of HCl concentration for the production of chitin. The results also showed that the optimized concentration 2 M HCl gave the minimum concentration of calcium and phosphorus compared to other concentrations applied in this experiment. In conclusion, the optimized concentration for demineralization process could be used commercially for the isolation or commercial production of chitin for agricultural, biomedical and biotechnological purposes. 相似文献