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111.
Ana Belen Jorge Rhodri Jervis Arun Prakash Periasamy Mo Qiao Jingyu Feng Linh Ngoc Tran Maria‐Magdalena Titirici 《Liver Transplantation》2020,10(11)
Sustainable energy production at an acceptable cost is key for its widespread application. At present, noble metals and metal oxides are the most widely used for electrocatalysis, but they suffer from low selectivity, poor durability, and scarcity. Because of this, metal‐free carbons have become the subject of great interest as promising alternative electrocatalysts for energy conversion and storage devices, and remarkable progress has been accomplished in the advance of metal‐free carbons as electrocatalysts for renewable energy technologies. Particularly interesting are 3D porous carbon architectures, which exhibit outstanding features for electrocatalysis applications, including broad range of active sites, interconnected porosity, high conductivity, and mechanical stability. This review summarizes the latest advances in 3D porous carbon structures for oxygen and hydrogen electrocatalysis. The structure–performance relationship of these materials is consequently rationalized and perspectives on creating more efficient 3D carbon electrocatalysts are suggested. 相似文献
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113.
Background
Differing approaches to menstrual hygiene management (MHM) have been associated with a wide range of health and psycho-social outcomes in lower income settings. This paper systematically collates, summarizes and critically appraises the available evidence.Methods
Following the PRISMA guidelines a structured search strategy was used to identify articles investigating the effects of MHM on health and psycho-social outcomes. The search was conducted in May 2012 and had no date limit. Data was extracted and quality of methodology was independently assessed by two researchers. Where no measure of effect was provided, but sufficient data were available to calculate one, this was undertaken. Meta-analysis was conducted where sufficient data were available.Results
14 articles were identified which looked at health outcomes, primarily reproductive tract infections (RTI). 11 articles were identified investigating associations between MHM, social restrictions and school attendance. MHM was found to be associated with RTI in 7 papers. Methodologies however varied greatly and overall quality was low. Meta-analysis of a subset of studies found no association between confirmed bacterial vaginosis and MHM (OR: 1.07, 95% CI: 0.52–2.24). No other substantial associations with health outcomes were found. Although there was good evidence that educational interventions can improve MHM practices and reduce social restrictions there was no quantitative evidence that improvements in management methods reduce school absenteeism.Conclusion
The management of menstruation presents significant challenges for women in lower income settings; the effect of poor MHM however remains unclear. It is plausible that MHM can affect the reproductive tract but the specific infections, the strength of effect, and the route of transmission, remain unclear. There is a gap in the evidence for high quality randomised intervention studies which combine hardware and software interventions, in particular for better understanding the nuanced effect improving MHM may have on girls’ attendance at school. 相似文献114.
115.
Belen Lorente-Galdos Jonathan Bleyhl Gabriel Santpere Laura Vives Oscar Ramírez Jessica Hernandez Roger Anglada Gregory M Cooper Arcadi Navarro Evan E Eichler Tomas Marques-Bonet 《Genome biology》2013,14(1):R9
Background
The identification of signatures of natural selection has long been used as an approach to understanding the unique features of any given species. Genes within segmental duplications are overlooked in most studies of selection due to the limitations of draft nonhuman genome assemblies and to the methodological reliance on accurate gene trees, which are difficult to obtain for duplicated genes.Results
In this work, we detected exons with an accumulation of high-quality nucleotide differences between the human assembly and shotgun sequencing reads from single human and macaque individuals. Comparing the observed rates of nucleotide differences between coding exons and their flanking intronic sequences with a likelihood-ratio test, we identified 74 exons with evidence for rapid coding sequence evolution during the evolution of humans and Old World monkeys. Fifty-five percent of rapidly evolving exons were either partially or totally duplicated, which is a significant enrichment of the 6% rate observed across all human coding exons.Conclusions
Our results provide a more comprehensive view of the action of selection upon segmental duplications, which are the most complex regions of our genomes. In light of these findings, we suggest that segmental duplications could be subjected to rapid evolution more frequently than previously thought. 相似文献116.
Belen Hurle Tomas Marques-Bonet Francesca Antonacci Inna Hughes Joseph F Ryan NISC Comparative Sequencing Program Evan E Eichler David M Ornitz Eric D Green 《BMC evolutionary biology》2011,11(1):23
Background
Mutations in the Otopetrin 1 gene (Otop1) in mice and fish produce an unusual bilateral vestibular pathology that involves the absence of otoconia without hearing impairment. The encoded protein, Otop1, is the only functionally characterized member of the Otopetrin Domain Protein (ODP) family; the extended sequence and structural preservation of ODP proteins in metazoans suggest a conserved functional role. Here, we use the tools of sequence- and cytogenetic-based comparative genomics to study the Otop1 and the Otop2-Otop3 genes and to establish their genomic context in 25 vertebrates. We extend our evolutionary study to include the gene mutated in Usher syndrome (USH) subtype 1G (Ush1g), both because of the head-to-tail clustering of Ush1g with Otop2 and because Otop1 and Ush1g mutations result in inner ear phenotypes. 相似文献117.
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119.
Valeria Stuardo Cristina Agustí José Manuel Godinez Alexandra Montoliu Aureli Torné Antoni Tarrats Carmen Alcalde Dolores Martín Eulalia Fernández-Montoli Cristina Vanrell Josefa Solé Yolanda Canet José Manuel Marqueta Jadiyettu Mohamed Isabel Cuenca Montserrat Lonca Guillem Sirera Elena Ferrer Pere Domingo Belen Lloveras Josep María Miro Silvia De Sanjosé Jordi Casabona 《PloS one》2012,7(10)
Background
High-risk human Papillomavirus infection is a necessary factor for cervical squamous intraepithelial lesions and invasive cervical cancer. In HIV-1-infected women, HPV infection is more prevalent and a higher risk of cervical cancer has been identified. We aimed to calculate the prevalence of infection by HR-HPV, determine the factors associated with this infection and abnormal cytology findings and to describe the history of cervical cancer screening in HIV-1-infected women.Methods
We enrolled 479 HIV-1–infected women from the PISCIS cohort. Each patient underwent a gynecological check-up, PAP smear, HPV AND Hybrid capture, HPV genotyping, and colposcopy and biopsy, if necessary. We applied questionnaires to obtain information on sociodemographic, behavioral, clinical, and cervical screening variables. We present a cross-sectional analysis.Results
Median age was 42 years. The prevalence of HR-HPV infection was 33.2% and that of high-grade squamous intraepithelial lesions (HSIL) was 3.8%. The most common genotypes were 16(23%), 53(20.3%), and 52(16.2%). The factor associated with HR-HPV infection was age <30 years (odds ratio[OR],2.5; 95%confidence interval[CI],1.1–5.6). The factors associated with the presence of HSIL or low-grade squamous intraepithelial lesions (LSIL) were CD4T-lymphocyte count <200cells/mm3 versus >500cells/mm3 (OR,8.4; 95%CI,3.7–19.2), HIV-1 viral load >10,000copies/mL versus <400copies/mL (OR,2.1; 95%CI,1.0–4.4), and use of oral contraceptives (OR,2.0; 95%CI,1.0–3.9). Sixty percent of HIV-1–infected women had had one Pap smear within the last 2 years.Conclusions
The high prevalence of HPV infection and cervical lesions in the HIV-1–infected population in Catalonia, as well as the low coverage and frequency of screening in this group, means that better preventive efforts are necessary and should include vaccination against HPV, better accessibility to screening programs, training of health care professionals, and specific health education for HIV-1–infected women. 相似文献120.
Zhao H Rubio B Sapra P Wu D Reddy P Sai P Martinez A Gao Y Lozanguiez Y Longley C Greenberger LM Horak ID 《Bioconjugate chemistry》2008,19(4):849-859
CPT-11, also known as irinotecan, is a prodrug that is approved for the treatment of advanced colorectal cancer. The active metabolite of CPT-11, SN38 (7-ethyl-10-hydroxy-camptothecin), has 100- to 1000-fold more potent cytotoxic activity in tissue cell culture compared with CPT-11. However, parental administration of SN38 is not possible because of its inherently poor water solubility. It is reported here that a multiarm poly(ethylene glycol) (PEG) backbone linked to four SN38 molecules (PEG-SN38) has been successfully prepared with high drug loading and significantly improved water solubility (400- to 1000-fold increase). Three different protecting strategies have been developed in order to selectively acylate the 20-OH of SN38 to preserve its E-ring in the lactone form (the active form of SN38 with cytotoxic activities) while PEG is still attached. One chemical process has been optimized to make a large quantity of the PEG-SN38 conjugate with a high yield that can be readily adapted for scale-up production. The PEG-SN38 conjugates have shown excellent in vitro anticancer activity, with potency similar to that of native SN38, in a panel of cancer cell lines. The PEG-SN38 conjugates also have demonstrated superior anticancer activity in the MX-1 xenograft mice model compared with CPT-11. Among the four conjugates, PEG-Gly-(20)-SN38 (23) has been selected as the lead candidate for further preclinical development. 相似文献