10 research outputs found

    Tracing the Distribution of European Lactase Persistence Genotypes Along the Americas

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    In adulthood, the ability to digest lactose, the main sugar present in milk of mammals, is a phenotype (lactase persistence) observed in historically herder populations, mainly Northern Europeans, Eastern Africans, and Middle Eastern nomads. As the –13910∗T allele in the MCM6 gene is the most well-characterized allele responsible for the lactase persistence phenotype, the –13910C > T (rs4988235) polymorphism is commonly evaluated in lactase persistence studies. Lactase non-persistent adults may develop symptoms of lactose intolerance when consuming dairy products. In the Americas, there is no evidence of the consumption of these products until the arrival of Europeans. However, several American countries’ dietary guidelines recommend consuming dairy for adequate human nutrition and health promotion. Considering the extensive use of dairy and the complex ancestry of Pan-American admixed populations, we studied the distribution of –13910C > T lactase persistence genotypes and its flanking haplotypes of European origin in 7,428 individuals from several Pan-American admixed populations. We found that the –13910∗T allele frequency in Pan-American admixed populations is directly correlated with allele frequency of the European sources. Moreover, we did not observe any overrepresentation of European haplotypes in the –13910C > T flanking region, suggesting no selective pressure after admixture in the Americas. Finally, considering the dominant effect of the –13910∗T allele, our results indicate that Pan-American admixed populations are likely to have higher frequency of lactose intolerance, suggesting that general dietary guidelines deserve further evaluation across the continent

    African evolutionary history inferred from whole genome sequence data of 44 indigenous African populations [plus Correction]

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    Background : Africa is the origin of modern humans within the past 300 thousand years. To infer the complex demographic history of African populations and adaptation to diverse environments, we sequenced the genomes of 92 individuals from 44 indigenous African populations. Results : Genetic structure analyses indicate that among Africans, genetic ancestry is largely partitioned by geography and language, though we observe mixed ancestry in many individuals, consistent with both short- and long-range migration events followed by admixture. Phylogenetic analysis indicates that the San genetic lineage is basal to all modern human lineages. The San and Niger-Congo, Afroasiatic, and Nilo-Saharan lineages were substantially diverged by 160 kya (thousand years ago). In contrast, the San and Central African rainforest hunter-gatherer (CRHG), Hadza hunter-gatherer, and Sandawe hunter-gatherer lineages were diverged by ~ 120–100 kya. Niger-Congo, Nilo-Saharan, and Afroasiatic lineages diverged more recently by ~ 54–16 kya. Eastern and western CRHG lineages diverged by ~ 50–31 kya, and the western CRHG lineages diverged by ~ 18–12 kya. The San and CRHG populations maintained the largest effective population size compared to other populations prior to 60 kya. Further, we observed signatures of positive selection at genes involved in muscle development, bone synthesis, reproduction, immune function, energy metabolism, and cell signaling, which may contribute to local adaptation of African populations. Conclusions : We observe high levels of genomic variation between ethnically diverse Africans which is largely correlated with geography and language. Our study indicates ancient population substructure and local adaptation of Africans

    PORTRAIT (Patient-Centered Outcomes Related to Treatment Practices in Peripheral Arterial Disease: Investigating Trajectories): Overview of Design and Rationale of an International Prospective Peripheral Arterial Disease Study

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    Background: Health status outcomes, including symptoms, functional status, and quality of life, are critically important outcomes from patients’ perspectives. The PORTRAIT study (Patient-Centered Outcomes Related to Treatment Practices in Peripheral Arterial Disease: Investigating Trajectories) was designed to prospectively define health status outcomes and examine associations between patients’ characteristics and care to these outcomes among those presenting with new-onset or worsened claudication. Methods and Results: PORTRAIT screened 3637 patients with an abnormal ankle-brachial index and new, or worsened, claudication symptoms from 16 peripheral arterial disease (PAD) specialty clinics in the United States, the Netherlands, and Australia between June 2, 2011, and December 3, 2015. Of the 1608 eligible patients, 1275 (79%) were enrolled. Before treatment, patients were interviewed to obtain their demographics, PAD symptoms and health status, psychosocial characteristics, preferences for shared decision-making, socioeconomic, and cardiovascular risk factors. Patients’ medical history, comorbidities, and PAD diagnostic information were abstracted from patients’ medical records. Serial information about patients’ health status, psychosocial, and lifestyle factors was collected at 3, 6, and 12 months by a core laboratory. Follow-up rates ranged from 84.2% to 91%. Clinical follow-up for PAD-related hospitalizations and major cardiovascular events is ongoing. Conclusions: PORTRAIT systematically collected serial PAD-specific health status data as a foundation for risk stratification, comparative effectiveness studies, and clinicians’ adherence to quality-based performance measures. Clinical Trial Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT01419080.Kim G. Smolderen, Kensey Gosch, Manesh Patel, W. Schuyler Jones, Alan T. Hirsch, John Beltrame, Rob Fitridge, Mehdi H. Shishehbor, Johan Denollet, Patrick Vriens, Jan Heyligers, Nancy Stone, MEd, Herbert Aronow, J. Dawn Abbott, Clementine Labrosciano, Rudolf Tutein-Nolthenius, John A. Spertu

    Matéria seca e altura das plantas de soja e arroz em função do grau de compactação e do teor de água de dois latossolos Height and dry matter of soybean and rice in function of degree of compaction and water content of two oxisols

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    Este trabalho teve o objetivo de avaliar a altura de plantas e a produção de matéria seca da parte aérea e das raízes de soja e arroz em dois teores de água (água retida a 0,05 e a 0,01 MPa) e três de resistência do solo à penetração (entre 0,25 e 6,46 MPa), determinados com o penetrômetro de anel dinamométrico. Foram utilizadas amostras de Latossolo Vermelho, distrófico, textura média (LVd) e Latossolo Vermelho, eutroférrico, textura argilosa (LVef), coletadas na profundidade de 0,0-0,20 m e compactadas em camadas de 0,03 m, em vasos de 0,20 m de altura e 0,25 m de diâmetro. A altura das plantas foi reduzida para valores de resistência à penetração superiores a 3,0 MPa. A menor produção de matéria seca da parte aérea das plantas ocorreu na resistência à penetração de 3,76 e 3,37 MPa para soja; 3,93 e 3,37 MPa para arroz, no Latossolo Vermelho, textura média e Latossolo Vermelho argiloso, respectivamente, no teor de água retida na tensão de 0,05 MPa, e no maior teor de água somente ocorreu redução da produção de matéria seca das raízes.<br>This research was carried out to evaluate the height of plants and production of aerial and root dry matter of soybean and rice in two water contents (water content at tension 0.05 and 0.01 MPa) and three levels of resistance to penetration (between 0.25 and 6.46 MPa) determined with penetrometer dinamometric ring. Samples of Haplustox and Eutrustox, medium and clayey texture were collected in depth of 0.0-0.20 m and compact in layers of 0.03 m in pots of 0.20 m of height and 0.25 m of diameter. The height of plants was reduced in values of penetration resistance greater of 3.0 MPa. The smaller production of aerial part dry matter of the plants occurred in penetration resistance of 3.76 and 3.37 MPa for soybean; 3.93 and 3.37 MPa for rice, in Haplustox and Eutrustox, respectively, in the water content in tension of 0.05 MPa, and in the greater water content only occurred reduction of root dry matter

    Physicians&apos; guideline adherence is associated with long-term heart failure mortality in outpatients with heart failure with reduced ejection fraction: the QUALIFY international registry

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    Background: Physicians&apos; adherence to guideline-recommended therapy is associated with short-term clinical outcomes in heart failure (HF) with reduced ejection fraction (HFrEF). However, its impact on longer-term outcomes is poorly documented. Here, we present results from the 18-month follow-up of the QUALIFY registry. Methods and results: Data at 18 months were available for 6118 ambulatory HFrEF patients from this international prospective observational survey. Adherence was measured as a continuous variable, ranging from 0 to 1, and was assessed for five classes of recommended HF medications and dosages. Most deaths were cardiovascular (CV) (228/394) and HF-related (191/394) and the same was true for unplanned hospitalizations (1175 CV and 861 HF-related hospitalizations, out of a total of 1541). According to univariable analysis, CV and HF deaths were significantly associated with physician adherence to guidelines. In multivariable analysis, HF death was associated with adherence level [subdistribution hazard ratio (SHR) 0.93, 95% confidence interval (CI) 0.87–0.99 per 0.1 unit adherence level increase; P = 0.034] as was composite of HF hospitalization or CV death (SHR 0.97, 95% CI 0.94–0.99 per 0.1 unit adherence level increase; P = 0.043), whereas unplanned all-cause, CV or HF hospitalizations were not (all-cause: SHR 0.99, 95% CI 0.9–1.02; CV: SHR 0.98, 95% CI 0.96–1.01; and HF: SHR 0.99, 95% CI 0.96–1.02 per 0.1 unit change in adherence score; P = 0.52, P = 0.2, and P = 0.4, respectively). Conclusion: These results suggest that physicians&apos; adherence to guideline-recommended HF therapies is associated with improved outcomes in HFrEF. Practical strategies should be established to improve physicians&apos; adherence to guidelines. © 2019 The Authors. European Journal of Heart Failure © 2019 European Society of Cardiolog

    Initial invasive or conservative strategy for stable coronary disease

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    BACKGROUND Among patients with stable coronary disease and moderate or severe ischemia, whether clinical outcomes are better in those who receive an invasive intervention plus medical therapy than in those who receive medical therapy alone is uncertain. METHODS We randomly assigned 5179 patients with moderate or severe ischemia to an initial invasive strategy (angiography and revascularization when feasible) and medical therapy or to an initial conservative strategy of medical therapy alone and angiography if medical therapy failed. The primary outcome was a composite of death from cardiovascular causes, myocardial infarction, or hospitalization for unstable angina, heart failure, or resuscitated cardiac arrest. A key secondary outcome was death from cardiovascular causes or myocardial infarction. RESULTS Over a median of 3.2 years, 318 primary outcome events occurred in the invasive-strategy group and 352 occurred in the conservative-strategy group. At 6 months, the cumulative event rate was 5.3% in the invasive-strategy group and 3.4% in the conservative-strategy group (difference, 1.9 percentage points; 95% confidence interval [CI], 0.8 to 3.0); at 5 years, the cumulative event rate was 16.4% and 18.2%, respectively (difference, 121.8 percentage points; 95% CI, 124.7 to 1.0). Results were similar with respect to the key secondary outcome. The incidence of the primary outcome was sensitive to the definition of myocardial infarction; a secondary analysis yielded more procedural myocardial infarctions of uncertain clinical importance. There were 145 deaths in the invasive-strategy group and 144 deaths in the conservative-strategy group (hazard ratio, 1.05; 95% CI, 0.83 to 1.32). CONCLUSIONS Among patients with stable coronary disease and moderate or severe ischemia, we did not find evidence that an initial invasive strategy, as compared with an initial conservative strategy, reduced the risk of ischemic cardiovascular events or death from any cause over a median of 3.2 years. The trial findings were sensitive to the definition of myocardial infarction that was used
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