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321.
Forbes SH; Hogg JT; Buchanan FC; Crawford AM; Allendorf FW 《Molecular biology and evolution》1995,12(6):1106-1113
We compared genotypes at eight (AC)n microsatellite loci in domestic sheep
(Ovis aries) and wild Rocky Mountain bighorn sheep (O. canadensis). The
domestic sheep had greater genetic variation, higher allele-size variances,
and larger allele sizes than the wild sheep. Accumulating evidence from
higher taxonomic comparisons shows that these parameters are biased if
microsatellite loci are selected in one taxon and used in another. Our
results demonstrate similar biases between congeneric species. We compared
standard measures of genetic variation, differentiation, and distance
within and between species (H, D, FST) to newer measures based on
allele-size variance (SW, SB, RST). The size-based distances better
detected species-level divergence, but standard measures better
distinguished allopatric populations. Empirical calibration of these
measures at the subspecies level is needed to establish their useful
ranges.
相似文献
322.
de Abreu Filipe Vieira Santos Macedo Mariana Viana da Silva Alex Junio Jardim de Oliveira Cirilo Henrique de Ottone Vinícius Oliveira de Almeida Marco Antônio Barreto dos Santos Edmilson da Cardoso Jader Cruz Campos Aline Scarpellini da Silva Claudia Maria Dornelles da Silva Amanda Gonzales de Andrade Miguel Souza Bernis Valéria Magro Octaviano Bernis Filho Walter Octaviano de Trindade Giliane Souza Albuquerque George Rego da Sevá Anaiá Paixão Ribeiro Bergmann Morais Teixeira Danilo Simonini Campos Fabrício Souza Franco Ana Cláudia Roehe Paulo Michel de Oliveira Danilo Bretas 《EcoHealth》2021,18(4):414-420
EcoHealth - In 2019, a new coronavirus disease (COVID-19) was detected in China. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was capable to infect domestic and captive mammals like... 相似文献
323.
In the present study we used K562 cells to demonstrate that insulin receptor substrate 1 (IRS-1) is expressed and constitutively phosphorylated in BCR-ABL(+) cells. We observed association between BCR-ABL/IRS-1, IRS-1/phosphoinositide 3'-kinase (PI3-kinase), and IRS-1/Grb2 in the K562 cell line. Our findings demonstrate that imatinib treatment resulted in marked attenuation of BCR-ABL/IRS-1 association and of IRS-1-stimulated PI3-kinase activity in K562 cells. We concluded that the IRS-1 protein is involved in the signalling pathway of the BCR-ABL tyrosine kinase. 相似文献
324.
Enny S. Paixao Christian Bottomley Julia M. Pescarini Kerry L. M. Wong Luciana L. Cardim Rita de Cssia Ribeiro Silva Elizabeth B. Brickley Laura C. Rodrigues Flavia Jse Oliveira Alves Maria do Carmo Leal Maria da Conceicao N. Costa Maria Gloria Teixeira Maria Yury Ichihara Liam Smeeth Mauricio L. Barreto Oona M. R. Campbell 《PLoS medicine》2021,18(10)
BackgroundThere is an increasing use of cesarean delivery (CD) based on preference rather than on medical indication. However, the extent to which nonmedically indicated CD benefits or harms child survival remains unclear. Our hypothesis was that in groups with a low indication for CD, this procedure would be associated with higher child mortality and in groups with a clear medical indication CD would be associated with improved child survival chances.Methods and findingsWe conducted a population-based cohort study in Brazil by linking routine data on live births between January 1, 2012 and December 31, 2018 and assessing mortality up to 5 years of age. Women with a live birth who contributed records during this period were classified into one of 10 Robson groups based on their pregnancy and delivery characteristics. We used propensity scores to match CD with vaginal deliveries (1:1) and prelabor CD with unscheduled CD (1:1) and estimated associations with child mortality using Cox regressions. A total of 17,838,115 live births were analyzed. After propensity score matching (PSM), we found that live births to women in groups with low expected frequencies of CD (Robson groups 1 to 4) had a higher death rate up to age 5 years if they were born via CD compared with vaginal deliveries (HR = 1.25, 95% CI: 1.22 to 1.28; p < 0.001). The relative rate was greatest in the neonatal period (HR = 1.39, 95% CI: 1.34 to 1.45; p < 0.001). There was no difference in mortality rate when comparing offspring born by a prelabor CD to those born by unscheduled CD. For the live births to women with a CD in a prior pregnancy (Robson group 5), the relative rates for child mortality were similar for those born by CD compared with vaginal deliveries (HR = 1.05, 95% CI: 1.00 to 1.10; p = 0.024). In contrast, for live births to women in groups with high expected rates of CD (Robson groups 6 to 10), the child mortality rate was lower for CD than for vaginal deliveries (HR = 0.90, 95% CI: 0.89 to 0.91; p < 0.001), particularly in the neonatal period (HR = 0.84, 95% CI: 0.83 to 0.85; p < 0.001). Our results should be interpreted with caution in clinical practice, since relevant clinical data on CD indication were not available.ConclusionsIn this study, we observed that in Robson groups with low expected frequencies of CD, this procedure was associated with a 25% increase in child mortality. However, in groups with high expected frequencies of CD, the findings suggest that clinically indicated CD is associated with a reduction in child mortality.In a study of linked population-based data, Enny Paixao and colleagues study the associations between cesarean section and child mortality among 17.8 million live births in Brazil. 相似文献
325.
Fred Bernardes Filho Claudia Maria Lincoln Silva Glauber Voltan Marcel Nani Leite Ana Laura Rosifini Alves Rezende Natlia Aparecida de Paula Josaf Gonalves Barreto Norma Tiraboschi Foss Marco Andrey Cipriani Frade 《PLoS neglected tropical diseases》2021,15(6)
BackgroundThis study evaluates implementation strategies for leprosy diagnosis based on responses to a Leprosy Suspicion Questionnaire (LSQ), and analyzes immunoepidemiological aspects and follow-up of individuals living in a presumptively nonendemic area in Brazil.Methodology/Principal findingsQuasi-experimental study based on LSQ throughout Jardinópolis town by community health agents, theoretical-practical trainings for primary care teams, dermatoneurological examination, anti-PGL-I serology, RLEP-PCR, and spatial epidemiology. A Leprosy Group (LG, n = 64) and Non-Leprosy Group (NLG, n = 415) were established. Overall, 3,241 LSQs were distributed; 1,054 (32.5%) LSQ were positive for signs/symptoms (LSQ+). Among LSQ+ respondents, Q2-Tingling (pricking)? (11.8%); Q4-Spots on the skin? (11.7%); Q7-Pain in the nerves? (11.6%); Q1-Numbness in your hands and/or feet? (10.7%) and Q8-Swelling of hands and feet? (8.5%) were most frequently reported symptoms. We evaluated 479 (14.8%) individuals and diagnosed 64 new cases, a general new case detection rate (NCDR) of 13.4%; 60 were among 300 LSQ+ (NCDR-20%), while 4 were among 179 LSQ negative (NCDR-2.23%). In LG, Q7(65%), Q2(60%), Q1(45%), Q4(40%) and Q8(25%) were most frequent. All 2x2 crossings of these 5 questions showed a relative risk for leprosy ranging from 3 to 5.8 compared with NLG. All patients were multibacillary and presented hypochromatic macules with loss of sensation. LG anti-PGL-I titers were higher than NLG, while 8.9% were positive for RLEP-PCR. The leprosy cases and anti-PGL-I spatial mappings demonstrated the disease spread across the town.Conclusions/SignificanceImplementation actions, primarily LSQ administration focused on neurological symptoms, indicate hidden endemic leprosy in a nonendemic Brazilian state. 相似文献
326.
Guilherme?de?OliveiraEmail authorView authors OrcID profile Bruno?de?Souza Barreto Daniela?da?Silva dos Santos Vinícius?Queiroz de Matos Maria?Cecília?Seara Santos 《Biological invasions》2018,20(10):2753-2765
Biological invasions and climate changes are the major causes of changes in biodiversity, which reduce, shift, and extinguish species ranges. While climate changes have been widely used in systematic conservation planning (SCP), biological invasions are rarely considered. Here, we combine the effects of climate changes and Artocarpus heterophyllus Lam. (Moraceae) invasion on the SCP for endemic aromatic fruit tree species from the Atlantic Forest (EFAF). We tested the effect of invasion on SCP measures of species turnover, biotic stability, and irreplaceability. Ecological niche models were used to establish species environmental suitability for the preindustrial period for both invasive species and EFAF and to forecast to the end of the century (2080–2100). We calculated the niche overlap between the invasive species and EFAF and tested the overlap significance using a null model. We tested the biological invasion effect on the results using results with no species invasion correction. The niche overlap between A. heterophyllus and EFAF was significant for 50% of species in the preindustrial period and for 33% in the future. The spatial patterns of species turnover, biotic stability, and irreplaceability had significant effects on biological invasion changing the spatial pattern in both shape and magnitude, which can misplace and overvalue conservation priorities. We showed that the disregard of biological invasion on SCP can cause negative effects on SCP under climate change. We strongly recommend accounting for biological invasion in the evaluation of SCP. 相似文献
327.
Sans M Figueiro G Ackermann E Barreto I Egaña A Bertoni B Poittevin-Gilmet E Maytia D Hidalgo PC 《Human biology; an international record of research》2011,83(1):55-70
Like other countries in the Americas, during its colonization Uruguay was the recipient of immigrants from several ethnic groups from Europe, as well as of enslaved Africans. After its independence in 1830, Basques were the first group of Europeans to arrive in the country. In this paper, we aim to contribute to the understanding of the process of integration of these migratory waves into the Uruguayan society. For that purpose, individuals of Basque origin from the city of Trinidad, Uruguay, were chosen to participate in this study. Particularly, we wanted to determine if Basque descendants in Uruguay remained relatively isolated or if they mixed with other ethnic groups. Mitochondrial DNA (mtDNA) of 60 self-identified Basque descendants, taken from a larger sample of subjects with Basque ancestors, was analyzed. The origin of mtDNA haplogroups was 77.8% European, 20.4% Amerindian, and 1.8% African, showing similar frequencies to other Uruguayan regions. Very few sequences showed a clear Basque origin, although other sources such as the Canary Islands are likely. Moreover, genetic distances clearly show that Basque descendants are genetically closer to other Uruguayan groups than to European populations, including Basques. It is possible to conclude that Basques and their descendants in the region of Trinidad did not remain isolated and that their marriage behavior was similar to that of other Uruguayan populations. However, to have a more accurate picture of the way Basques intermarried with other populations in Uruguay, new analyses are needed that take into account paternal lineages as well as biparental genetic markers. 相似文献
328.
329.
N Neirynck S Eloot G Glorieux DV Barreto FC Barreto S Liabeuf A Lenglet HD Lemke ZA Massy R Vanholder 《PloS one》2012,7(8):e44201
Background
Uremic solute concentration increases as Glomerular Filtration Rate (GFR) declines. Weak associations were demonstrated between estimated GFR (eGFR) and the concentrations of several small water-soluble and protein-bound uremic solutes (MW<500Da). Since also middle molecular weight proteins have been associated with mortality and cardiovascular damage in Chronic Kidney Disease (CKD), we investigated the association between several eGFR formulae and the concentration of Low Molecular Weight Proteins (LMWP) (MW>500Da).Materials and Methods
In 95 CKD-patients (CKD-stage 2–5 not on dialysis), associations between different eGFR-formulae (creatinine, CystatinC-based or both) and the natural logarithm of the concentration of several LMWP’s were analyzed: i.e. parathyroid hormone (PTH), Cystatin C (CystC), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), leptin, retinol binding protein (RbP), immunoglobin light chains kappa and lambda (Ig-κ and Ig-λ), beta-2-microglobulin (β2M), myoglobin and fibroblast growth factor-23 (FGF-23)).Results
The regression coefficients (R2) between eGFR, based on the CKD-EPI-Crea-CystC-formula as reference, and the examined LMWP’s could be divided into three groups. Most of the LMWP’s associated weakly (R2 <0.2) (FGF-23, leptin, IL-6, TNF-α, Ig-κ, Ig-λ) or intermediately (R2 0.2–0.7) (RbP, myoglobin, PTH). Only β2M and CystC showed a strong association (R2 >0.7). Almost identical R2-values were found per LMWP for all eGFR-formulae, with exception of CystC and β2M which showed weaker associations with creatinine-based than with CystC-based eGFR.Conclusion
The association between eGFR and the concentration of several LMWP’s is inconsistent, with in general low R2-values. Thus, the use of eGFR to evaluate kidney function does not reflect the concentration of several LMWP’s with proven toxic impact in CKD. 相似文献330.