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L Madrigal 《Human biology; an international record of research》1992,64(2):199-213
Cross-cultural studies of sex-specific mortality indicate that, whereas males experience their greatest mortality in industrialized societies, females experience their greatest mortality in populations with low life expectancy. The higher mortality of females in low-life-expectancy communities has been interpreted as a reflection of nutritional and health-care discrimination against females. Cross-cultural demographic studies also indicate that males have a higher frequency of violent and accidental deaths, possibly because of more frequent risky behaviors. This study focuses on Escazu, a rural nineteenth-century population from Costa Rica with low life expectancy. I investigate whether Escazu males had higher violent and accidental deaths and whether females had higher diarrhea-related deaths, an indication of nutritional discrimination. An analysis of mortality by cause of death indicates that males and females did not experience significantly different diarrhea-related death rates, although males did experience greater violent mortality. This study illustrates that more anthropological community-specific studies of mortality are needed to elucidate variation of death rates within large national or international regions. 相似文献
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W H Hildebrand J A Madrigal M P Belich J Zemmour F E Ward R C Williams P Parham 《Journal of immunology (Baltimore, Md. : 1950)》1992,149(11):3563-3568
Previous analysis has emphasized the correlation between primary structures of class I HLA molecules and their patterns of serologic cross-reactivity. Here we describe the structures of two serologic groups of HLA-B alleles for which this is not the case. HLA-B45, an allele associated with black populations, is serologically paired with B44 in the B12 group; its structure, however, is divergent from that of B44 but closely related to B50. The BN21 (B*4005) allele is associated with native Americans and is serologically grouped with B50 in the B21 group; its structure, however, is more closely related to alleles of the B40 group. The B44 and B45 serologically cross-reactive molecules differ at seven functional positions of the Ag recognition site; the B50 and BN21 molecules differ at four such residues. These differences are predicted to alter peptide presentation and be capable of eliciting strong alloreactive T cell responses. For these pairs of B12 and B21 Ag, serology appears dominated by epitopes formed by short sequences of the alpha 2 helix which have been shuffled by recombination between alleles. The implications of these results for HLA matching in transplantation are discussed. 相似文献
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Hans Erik Bøtker Hector Alejandro Cabrera-Fuentes Marisol Ruiz-Meana Gerd Heusch Michel Ovize 《Journal of cellular and molecular medicine》2020,24(5):2717-2729
Pre-clinical studies have indicated that mitoprotective drugs may add cardioprotection beyond rapid revascularization, antiplatelet therapy and risk modification. We review the clinical efficacy of mitoprotective drugs that have progressed to clinical testing comprising cyclosporine A, KAI-9803, MTP131 and TRO 40303. Whereas cyclosporine may reduce infarct size in patients undergoing primary angioplasty as evaluated by release of myocardial ischaemic biomarkers and infarct size imaging, the other drugs were not capable of demonstrating this effect in the clinical setting. The absent effect leaves the role of the mitochondrial permeability transition pore for reperfusion injury in humans unanswered and indicates that targeting one single mechanism to provide mitoprotection may not be efficient. Moreover, the lack of effect may relate to favourable outcome with current optimal therapy, but conditions such as age, sex, diabetes, dyslipidaemia and concurrent medications may also alter mitochondrial function. However, as long as the molecular structure of the pore remains unknown and specific inhibitors of its opening are lacking, the mitochondrial permeability transition pore remains a target for alleviation of reperfusion injury. Nevertheless, taking conditions such as ageing, sex, comorbidities and co-medication into account may be of paramount importance during the design of pre-clinical and clinical studies testing mitoprotective drugs. 相似文献
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Lilia Montoya Lourdes B. Celis Marisol Gallegos‐García Elías Razo‐Flores Ángel G. Alpuche‐Solís 《Engineering in Life Science》2013,13(3):302-311
Sulfate reduction is an appropriate approach for the treatment of effluents with sulfate and dissolved metals. In sulfate‐reducing reactors, acetate may largely contribute to the residual organic matter, because not all sulfate reducers are able to couple the oxidation of acetate to the reduction of sulfate, limiting the treatment efficiency. In this study, we investigated the diversity of a bacterial community in the biofilm of a laboratory scale down‐flow fluidized bed reactor, which was developed under sulfidogenic conditions at an influent pH between 4 and 6. The sequence analysis of the microbial community showed that the 16S rRNA gene sequence of almost 50% of the clones had a high similarity with Anaerolineaceae. At second place, 33% of the 16S rRNA phylotypes were affiliated with the sulfate‐reducing bacteria Desulfobacca acetoxidans and Desulfatirhabdium butyrativorans, suggesting that acetotrophic sulfate reduction was occurring in the system. The remaining bacterial phylotypes were related to fermenting bacteria found at the advanced stage of reactor operation. The results indicate that the acetotrophic sulfate‐reducing bacteria were able to remain within the biofilm, which is a significant result because few natural consortia harbor complete oxidizing sulfate‐reducers, improving the acetate removal via sulfate reduction in the reactor. 相似文献
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Carolina Gomes Diana Ferreira João P. F. Carvalho Carlos A. V. Barreto Joana Fernandes Marisol Gouveia Fernando Ribeiro Ana S. Duque Sandra I. Vieira 《Biotechnology and bioengineering》2020,117(8):2610-2628
Hypertension is a major and highly prevalent risk factor for various diseases. Among the most frequently prescribed antihypertensive first-line drugs are synthetic angiotensin I-converting enzyme inhibitors (ACEI). However, since their use in hypertension therapy has been linked to various side effects, interest in the application of food-derived ACEI peptides (ACEIp) as antihypertensive agents is rapidly growing. Although promising, the industrial production of ACEIp through conventional methods such as chemical synthesis or enzymatic hydrolysis of food proteins has been proven troublesome. We here provide an overview of current antihypertensive therapeutics, focusing on ACEI, and illustrate how biotechnology and bioengineering can overcome the limitations of ACEIp large-scale production. Latest advances in ACEIp research and current genetic engineering-based strategies for heterologous production of ACEIp (and precursors) are also presented. Cloning approaches include tandem repeats of single ACEIp, ACEIp fusion to proteins/polypeptides, joining multivariate ACEIp into bioactive polypeptides, and producing ACEIp-containing modified plant storage proteins. Although bacteria have been privileged ACEIp heterologous hosts, particularly when testing for new genetic engineering strategies, plants and microalgae-based platforms are now emerging. Besides being generally safer, cost-effective and scalable, these “pharming” platforms can perform therelevant posttranslational modifications and produce (and eventually deliver) biologically active protein/peptide-based antihypertensive medicines. 相似文献
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Soil conditions may change the response of plants to inoculation with arbuscular mycorrhizal fungi (AMF). This, in turn, may influence the development of mycorrhizal associations. The effect of AM species isolated from different ecosystems was evaluated on Pueraria phaseoloides (kudzu). Experiments were conducted under controlled conditions in Leonard jars, on a substrate made of peat, rice husk, and vermiculite (1-1-1) enriched with rock phosphate plus a modified Hoagland nutrient solution. In the first experiment the initial pH of the substrate (8.0) was reduced by approximately one unit by inoculation with Kuklospora colombiana, Glomus clarum, and Glomus manihotis. The result was the same for Acaulospora longula species when 4-morpholine ethanesulphonic acid (MES) buffer was used. The final pH of the substrate was correlated with the above-ground plant biomass production suggesting that the most effective fungus regulated the pH of the substrate. This positive interaction leads to a higher concentration of P and K in plants. When the pH of the substrate was buffered with MES, in the second experiment, the efficiency of K. colombiana was reduced, even though plants inoculated with this fungus yielded more than non-inoculated plants. G. intraradices and A. longula were favoured by buffer addition. Beneficial buffer effects on this plant resulted in lower pH, better plant P and K uptake, and higher biomass production. The best plant yield was obtained at pH 7.0 in both experiments. G. clarum and G. manihotis yielded the highest biomass production. Under the proposed conditions, AMF improved P. phaseoloides growth and pH regulation. These growth conditions may be used for the evaluation and propagation of some AMF species adding MES buffer in the nutrient solution. 相似文献
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Raquel Rodríguez-López Marisol Donoso María Fernández-Cavada Luz María González Aranza Margallo César Corral Mercedes Gallego María Teresa García de Cáceres Trinidad Herrera Cristina González José Manuel Vagace Guillermo Gervasini 《Gene》2013
Two single nucleotide polymorphisms (SNPs) in the Human Hemochromatosis (HFE) gene, C282Y and H63D, are the major variants associated to altered iron status and it is well known that these mutations are in linkage disequilibrium with certain Human Leukocyte Antigen (HLA)-A alleles. In addition, the C282Y SNP has been previously suggested to confer susceptibility to acute lymphoblastic leukemia (ALL). We have aimed to assess the diagnosis utility of these polymorphisms in a population of Spanish subjects with suspicion of hereditary iron overload and to evaluate the effect of their associations with HLA-A alleles on the susceptibility to ALL. Both the 63DD [OR = 4.31 (1.7–11.2)] and 282YY (p for trend = 0.02) genotypes were more frequently found among subjects with suspicion of iron overload than among controls. 282YY carriers displayed significantly higher transferrin saturation index (TSI) values (p < 0.001) as well as serum iron (p = 0.01) and ferritin (p = 0.01) levels. In addition, transferrin levels were lower in these subjects (p = 0.01). Likewise, patients who were carriers of the compound heterozygous diplotype (282CY/63HD) showed significantly higher TSI and serum iron and ferritin concentrations. The H63D SNP did not significantly affect the analytical parameters measured. All 282YY carriers and 69.2% of compound heterozygotes showed an altered biochemical index. The frequencies of the HFE SNPs in ALL pediatric patients were lower than those found in controls, whereas the HLA-A*24 allele was significantly overrepresented in the patients group [OR = 3.76 (1.9–7.3)]. No HFE-HLA-A associations were found to modulate the ALL risk. These results suggest that it may be useful to test for both HFE H63D and C282Y polymorphisms in patients with iron overload, as opposed to just genotyping for the C282Y SNP, which is customary in some healthcare centers. These HFE variants and their associations with HLA-A alleles were not observed to be relevant for the susceptibility to ALL in our population. 相似文献