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41.
Regina Maria Barbosa Cristiane da Silva Cabral Tania di Giacomo do Lago Adriana de Araujo Pinho 《PloS one》2016,11(11)
BackgroundIn many countries, young women of reproductive age have been especially affected by the HIV epidemic, which have fostered research to better understand how HIV infection influences and shapes women´s fertility and reproductive and sexual decisions. In Brazil, few studies have focused on the impact of the HIV epidemic on contraceptive choices among women living with HIV (WLHIV).ObjectiveThis study evaluates the impact HIV infection may have in the access to female sterilization in Brazil, using a time-to-event analysis.MethodsA cross-sectional quantitative study (GENIH study) was conducted between February 2013 and April 2014 in the city of São Paulo, comparing two probabilistic samples of 975 WLHIV and 1,003 women not living with HIV (WNLHIV) aged 18 to 49. Sexual and reproductive data was collected retrospectively in order to reconstruct women''s reproductive trajectories. Given the objectives of this study, the analysis was restricted to women with parity one or more and, in case of WLHIV, to those sterilized after HIV diagnosis and not infected through vertical transmission. The final sample analysis included 683 WNLHIV and 690 WLHIV. A series of multivariable-adjusted Cox models estimated the probability of being sterilized after HIV diagnosis, compared with WNLHIV. Models were adjusted for schooling, race/color, and stratified by parity at last delivery (1–2, 3+). Hazard ratios were calculated for female sterilization, and separately for interval and postpartum procedures (performed in conjunction with caesarean section or immediately after vaginal delivery). Additionally, information regarding unmet demand for female sterilization was also explored.FindingsNo statistical difference in the overall risk of sterilization between WLHIV and WNLHIV in the two parity-related groups is observed: HR = 0.88 (0.54–1.43) and 0.94 (0.69–1.29), respectively, among women with 1–2 children and those with three and more. However, significant differences regarding the impact of HIV infection at sterilization are observed depending on the timing and the type of sterilization procedure. The probability of obtaining an interval sterilization is significantly lower for WLHIV compared to those not living with HIV. The reverse occurs regarding postpartum sterilization. Although sterilization is mainly performed in conjunction with caesarean section in Brazil, it is evident that caesarean sections are not the sole factor increasing the risk of sterilization among WLHIV.ConclusionThe results indicate barriers in the access to services offering interval sterilization for WLHIV and certain facilitation in obtaining the procedure in conjunction with caesarean section. Health policy makers at local and national levels should promote institutional changes in order to facilitate access to interval sterilization and to confront the sensitive discussion of WLHIV’s eligibility for postpartum sterilization. It is also urgent to increase access to a wider range of contraceptive methods for WLHIV and promote dual method protection strategies. Moreover, since condom use may decrease in the future in the context of the preventive effect of antiretroviral therapy, promoting dual methods will expand the choices regarding the reproductive rights of women living with HIV. 相似文献
42.
Vanessa Mendonça Diana Boaventura Henrique Cabral Ana C. F. Silva 《Marine Biology Research》2016,12(2):125-132
Chitons are very common molluscs on European rocky shores. They are common prey of fish and crabs and often display several colour morphs within a given habitat. Predation is one of the potential mechanisms accounting for chiton colour polymorphism. The colour variation is considered to provide a camouflage protection through a match with the substratum surface typology. However, the effectiveness of chiton polymorphism as a predation defence requires further investigation. Previously we found a relationship between chiton colour morphs and substrate characteristics, with chitons most commonly found on substrates that were of similar colour to their shells. Here, we examined whether each morph displayed an active choice for matching the substratum. Next, we assessed if the predation success of the intertidal common crab Carcinus maenas varied significantly with the absence/presence of an apparent camouflage effect created between the chiton colour morph and the substratum type. The present study indicates that chiton colour morphs probably actively choose substratum types where they blend in. Carcinus maenas was able to prey on all Lepidochitona cinereus colour morphs, regardless of the substrate camouflage effect. Surprisingly, the predation frequency was higher on camouflaged chitons than on contrasting chitons. It was concluded that chiton camouflage is probably not a defence mechanism against predation by the crab C. maenas, and that chiton colour polymorphism is probably promoted by other, more visual predators. 相似文献
43.
Guillaume Lentendu Paulo Roberto Bressan Buosi Adalgisa Fernada Cabral Bianca Trevizan Segvia Bianca Ramos Meira Fernando Miranda Lansac‐Tha Luiz Felipe Machado Velho Camila D. Ritter Micah Dunthorn 《The Journal of eukaryotic microbiology》2019,66(4):592-599
The biodiversity and biogeography of protists inhabiting many ecosystems have been intensely studied using different sequencing approaches, but tropical ecosystems are relatively under‐studied. Here, we sampled planktonic waters from 32 lakes associated with four different river–floodplains systems in Brazil, and sequenced the DNA using a metabarcoding approach with general eukaryotic primers. The lakes were dominated by the largely free‐living Discoba (mostly the Euglenida), Ciliophora, and Ochrophyta. There was low community similarity between lakes even within the same river–floodplain. The protists inhabiting these floodplain systems comprise part of the large and relatively undiscovered diversity in the tropics. 相似文献
44.
Ctia Bandeiras Joaquim M. S. Cabral Robert A. Gabbay Stan N. Finkelstein Frederico Castelo Ferreira 《Biotechnology journal》2019,14(8)
Differentiation of pluripotent stem cells (PSCs) into β cells could provide insulin independence for type 1 diabetes (T1D) patients. This approach would reduce the clinical complications that most patients managed on intensive insulin therapy (IIT) face. However, bottlenecks of PSC manufacturing and limited engraftment of encapsulated cells hinder the long‐term effectiveness of these therapies. A bioprocess decision‐support tool is combined with a disease state‐transition model to evaluate the cost‐effectiveness of the stem cell‐based therapy against IIT. Clinical effectiveness is assessed in quality‐adjusted life years (QALYs). Manufacturing costs per patient reduce from $430 000 to $160 000 with optimization of batch size and annual demand. For 96% of the patients, cell therapy improves the quality of life compared to IIT. Cost savings are achieved for 2% of the population through prevention of renal disease. The therapy is cost‐effective for 3.4% of patients when a willingness to pay (WTP) of up to $150 000 per QALY is considered. A 75% cost reduction in the cell therapy price increases cost‐effectiveness likelihood to 51% at $100 000 per QALY. This study highlights the need for scalable manufacturing platforms for stem cell therapies, as well as to prioritizing access to the therapy to patients with an increased likelihood of costly complications. 相似文献
45.
Eduardo Estrada José A Villarreal César Cantú Ismael Cabral Laura Scott Carmen Yen 《Journal of ethnobiology and ethnomedicine》2007,3(1):1-8
The archives of Flora Medicinal, an ancient pharmaceutical laboratory that supported ethnomedical research in Brazil for more than 30 years, were searched for plants with antimalarial use. Forty plant species indicated to treat malaria were described by Dr. J. Monteiro da Silva (Flora Medicinal leader) and his co-workers. Eight species, Bathysa cuspidata, Cosmos sulphureus, Cecropia hololeuca, Erisma calcaratum, Gomphrena arborescens, Musa paradisiaca, Ocotea odorifera, and Pradosia lactescens, are related as antimalarial for the first time in ethnobotanical studies. Some species, including Mikania glomerata, Melampodium divaricatum, Galipea multiflora, Aspidosperma polyneuron, and Coutarea hexandra, were reported to have activity in malaria patients under clinical observation. In the information obtained, also, there were many details about the appropriate indication of each plant. For example, some plants are indicated to increase others' potency. There are also plants that are traditionally employed for specific symptoms or conditions that often accompany malaria, such as weakness, renal failure or cerebral malaria. Many plants that have been considered to lack activity against malaria due to absence of in vitro activity against Plasmodium can have other mechanisms of action. Thus researchers should observe ethnomedical information before deciding which kind of screening should be used in the search of antimalarial drugs. 相似文献
46.
Tiago Manuel Fernandes Mendes Emanuel Carrilho Ana Júlia Pinto Fonseca Sieuve Afonso Carlos Alexandre Galinaro Fernanda Janku Cabral Silmara Marques Allegretti 《International journal for parasitology》2019,49(13-14):1049-1060
Mansonic schistosomiasis is a neglected disease transmitted by Biomphalaria spp. snails. Understanding what happens inside the intermediate host is important to develop more efficient ways of reducing schistosomiasis prevalence. Our purpose was to characterize metabolic and immunological changes in Biomphalaria glabrata 24 h after exposure to Schistosoma mansoni. For this purpose, proteins were extracted from snails’ whole tissue with Tris-Urea buffer and digested with tripsin. Mass spectrometry was performed and analyzed with MaxQuant and Perseus software. Also, the hemolymph of five snails 24 h post exposure was collected, and the numbers of hemocytes, levels of urea, uric acid, nitric oxide, calcium, glycogen and alanine and aspartate aminotransferases activities were assessed. Snails were also dissected for measurement of glycogen content in the cephalopodal region and gonoda-digestive gland complex. Globin domain proteins were found to be up-regulated; also the number of circulating hemocytes was significantly higher after 24 h of exposure to the parasite. NO levels were higher 24 h post exposure. Several proteins associated with energy metabolism were found to be up-regulated. Glycogen analysis showed a significant decrease in the gonad-digestive gland complex glycogen content. We found several proteins which seem to be associated with the host immune response, most of which were up-regulated, however some were down-regulated, which may represent an important clue in understanding B. glabrata – S. mansoni compatibility. 相似文献
47.
Taciana S. do Carmo Felipe S. Moreira Bruna V. Cabral Raquel C. C. Dantas Vicelma L. Cardoso 《Geomicrobiology journal》2019,36(3):195-203
In this paper, we are presenting a biological process to recover phosphorus by solubilizing low-grade phosphate rocks. To this end, the efficiency of different phosphate-solubilizing microorganism (PSM) species for solubilizing P from phosphate rocks using both pure cultures and associations. Nutritional conditions, phosphate rock concentrations, and reactor designs were tested. The genus Bacillus, especially Bacillus megaterium (ATCC 14581), was found to be the most promising PSM for solubilizing P. Production of organic acids and acidic pH values were shown to be directly related to P solubilizing. However, associations between tested microorganisms did not significantly enhance process efficiency. We conclude that nutritional factors of the medium are important to solubilization, and lower phosphate rock concentrations lead to better solubilization. The Air Lift reactor was promising for B. megaterium (ATCC 14581), but adaptations are needed for further tests. 相似文献
48.
49.
Photorhabdus sp. strain Az29 is symbiotic with an Azorean nematode of the genus Heterorhabditis in a complex that is highly virulent to insects even at low temperatures. The virulence of the bacteria is mainly attributed to toxins and bacterial enzymes secreted during parasitism. The bacteria secrete proteases during growth, with a peak at the end of the exponential growth phase. Protease secretion was higher in cultures growing at lower temperatures. At 10 degrees C the activity was highest and remained constant for over 7 days, whereas at 23 and 28 degrees C it showed a steady decrease. Two proteases, PrtA and PrtS, that are produced in the growth medium were purified by liquid chromatography. PrtA was inhibited by 1,10-phenantroline and by EDTA and had a molecular mass of 56 kDa and an optimal activity at pH 9 and 50 degrees C. Sequences of three peptides of PrtA showed strong homologies with alkaline metalloproteases from Photorhabdus temperata K122 and Photorhabdus luminescens W14. Peptide PrtA-36 contained the residues characteristic of metzincins, known to be involved in bacterial virulence. In vitro, PrtA inhibited antibacterial factors of inoculated Lepidoptera and of cecropins A and B. PrtS had a molecular mass of 38 kDa and was inhibited by 1,10-phenanthroline but not by EDTA. Its activity ranged between 10 and 80 degrees C and was optimal at pH 7 and 50 degrees C. PrtS also destroyed insect antibacterial factors. Three fragments of PrtS showed homology with a putative metalloprotease of P. luminescens TTO1. Polyclonal antibody raised against PrtA did not recognize PrtS, showing they are distinct molecules. 相似文献
50.
Valente CA Prazeres DM Cabral JM Monteiro GA 《Applied and environmental microbiology》2004,70(8):5033-5036
The yield of human alpha 2b interferon in Escherichia coli was optimized by replacement of low-usage arginine codons located in the mRNA 5' end. The differences observed among the various gene variants suggest that codon usage, Shine-Dalgarno-like sequences, and mRNA secondary structure contribute to the performance of E. coli translation machinery. 相似文献