22 research outputs found
Is the karyotype of neotropical boid snakes really conserved? Cytotaxonomy, chromosomal rearrangements and karyotype organization in the Boidae family
Boids are primitive snakes from a basal lineage that is widely distributed in Neotropical region. Many of these species are both morphologically and biogeographically divergent, and the relationship among some species remains uncertain even with evolutionary and phylogenetic studies being proposed for the group. For a better understanding of the evolutionary relationship between these snakes, we cytogenetically analysed 7 species and 3 subspecies of Neotropical snakes from the Boidae family using different chromosomal markers. The karyotypes of Boa constrictor occidentalis, Corallus hortulanus, Eunectes notaeus, Epicrates cenchria and Epicrates assisi are presented here for the first time with the redescriptions of the karyotypes of Boa constrictor constrictor, B. c. amarali, Eunectes murinus and Epicrates crassus. The three subspecies of Boa, two species of Eunectes and three species of Epicrates exhibit 2n = 36 chromosomes. In contrast, C. hortulanus presented a totally different karyotype composition for the Boidae family, showing 2n = 40 chromosomes with a greater number of macrochromosomes. Furthermore, chromosomal mapping of telomeric sequences revealed the presence of interstitial telomeric sites (ITSs) on many chromosomes in addition to the terminal markings on all chromosomes of all taxa analysed, with the exception of E. notaeus. Thus, we demonstrate that the karyotypes of these snakes are not as highly conserved as previously thought. Moreover, we provide an overview of the current cytotaxonomy of the group. © 2016 Viana et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
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Race/Ethnic Differences in Outcomes Among Hospitalized Medicare Patients With Heart Failure and Preserved Ejection Fraction.
ObjectivesThis study analyzed HFpEF patient characteristics and clinical outcomes according to race/ethnicity and adjusted for patient and hospital characteristics along with socioeconomic status (SES).BackgroundThe proportion of hospitalizations for heart failure with preserved ejection fraction (HFpEF) has increased over the last decade. Whether the short- and long-term outcomes differ between racial/ethnic groups is not well described.MethodsThe Get With The Guidelines-Heart Failure registry was linked to Medicare administrative data to identify hospitalized patients with HFpEF ≥65 years of age with left ventricular ejection fraction ≥50% between 2006 and 2014. Cox proportional hazards models were used to report hazard ratios (HRs) for 30-day and 1-year readmission and mortality rates with sequential adjustments for patient characteristics, hospital characteristics, and SES.ResultsThe final cohort included 53,065 patients with HFpEF. Overall 30-day mortality was 5.87%; at 1 year, it was 33.1%. The 30-day all-cause readmission rate was 22.2%, and it was 67.0% at 1 year. After adjusting for patient characteristics, hospital characteristics, and SES, 30-day mortality was lower for black patients (HR: 0.84; 95% confidence interval [CI]: 0.71 to 0.98; p = 0.031) and Hispanic patients (HR: 0.78; 95% CI: 0.64 to 0.96; p = 0.017) compared with white patients. One-year mortality was lower for black patients (HR: 0.93; 95% CI: 0.87 to 0.99; p = 0.031), Hispanic patients (HR: 0.83; 95% CI: 0.75 to 0.91; p < 0.001), and Asian patients (HR: 0.76; 95% CI: 0.66 to 0.88; p < 0.001) compared with white patients. Black patients had a higher risk of readmission at 30 days (HR: 1.09; 95% CI: 1.02 to 1.16; p = 0.012) and 1 year (HR: 1.14; 95% CI: 1.09 to 1.20; p < 0.001) compared with white patients.ConclusionsBlack, Hispanic, and Asian patients had a lower mortality risk after a hospitalization for HFpEF compared with white patients; black patients had higher readmission rates. These differences in mortality and readmission risk according to race/ethnicity persisted after adjusting for patient characteristics, SES, and hospital factors
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Medicare Expenditures by Race/Ethnicity After Hospitalization for Heart Failure With Preserved Ejection Fraction.
ObjectivesThe purpose of this study was to analyze cumulative Medicare expenditures at index admission and after discharge by race or ethnicity.BackgroundHeart failure with preserved ejection fraction (HFpEF) is a growing proportion of heart failure (HF) admissions. Research on health care expenditures for patients with HFpEF is limited.MethodsRecords of patients discharged from the Get With The Guidelines-Heart Failure registry between 2006 and 2014 were linked to Medicare data. The primary outcome was unadjusted payments for acute care services. Comparisons between race/ethnic groups were made using generalized linear mixed models. Cost ratios were reported by race/ethnicity, and adjustments were made sequentially for patient characteristics, hospital factors, and regional socioeconomic status.ResultsMedian Medicare costs for index hospitalizations were 7,049 for whites, 8,808 for Hispanics, 8,963 for other races. Median costs at 30 days for readmitted patients were 17,456 for the entire cohort at 1-year. No significant differences were seen in index admission cost ratios by race/ethnicity. At 30 days among readmitted patients, costs were 9% higher (95% confidence interval [CI]: 1% to 17%; p = 0.020) for blacks in the fully adjusted model than whites. At 1 year, costs were 14% higher (95% CI: 9% to 18%; p < 0.001) for blacks, 7% higher (95% CI: 0% to 14%; p = 0.041) for Hispanics, and 24% higher (95% CI: 8% to 42%; p = 0.003) for patients of other races. No significant differences between white and Asian expenditures were noted.ConclusionsMinority patients with HFpEF have greater acute care service costs. Further research of improving care delivery is needed to reduce acute care use for vulnerable populations
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Medicare Expenditures by Race/Ethnicity After Hospitalization for Heart Failure With Preserved Ejection Fraction.
OBJECTIVES:The purpose of this study was to analyze cumulative Medicare expenditures at index admission and after discharge by race or ethnicity. BACKGROUND:Heart failure with preserved ejection fraction (HFpEF) is a growing proportion of heart failure (HF) admissions. Research on health care expenditures for patients with HFpEF is limited. METHODS:Records of patients discharged from the Get With The Guidelines-Heart Failure registry between 2006 and 2014 were linked to Medicare data. The primary outcome was unadjusted payments for acute care services. Comparisons between race/ethnic groups were made using generalized linear mixed models. Cost ratios were reported by race/ethnicity, and adjustments were made sequentially for patient characteristics, hospital factors, and regional socioeconomic status. RESULTS:Median Medicare costs for index hospitalizations were 7,049 for whites, 8,808 for Hispanics, 8,963 for other races. Median costs at 30 days for readmitted patients were 17,456 for the entire cohort at 1-year. No significant differences were seen in index admission cost ratios by race/ethnicity. At 30 days among readmitted patients, costs were 9% higher (95% confidence interval [CI]: 1% to 17%; p = 0.020) for blacks in the fully adjusted model than whites. At 1 year, costs were 14% higher (95% CI: 9% to 18%; p < 0.001) for blacks, 7% higher (95% CI: 0% to 14%; p = 0.041) for Hispanics, and 24% higher (95% CI: 8% to 42%; p = 0.003) for patients of other races. No significant differences between white and Asian expenditures were noted. CONCLUSIONS:Minority patients with HFpEF have greater acute care service costs. Further research of improving care delivery is needed to reduce acute care use for vulnerable populations
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Long-term outcomes for heart failure patients with and without diabetes: From the Get With The Guidelines-Heart Failure Registry.
BackgroundDiabetes mellitus is an increasingly prevalent condition among heart failure (HF) patients. The long-term morbidity and mortality among patients with and without diabetes with HF with reduced (HFrEF), borderline (HFbEF), and preserved ejection fraction (HFpEF) are not well described.MethodsUsing the Get With The Guidelines (GWTG)-HF Registry linked to Centers for Medicare & Medicaid Services claims data, we evaluated differences between HF patients with and without diabetes. Adjusted Cox proportional-hazard models controlling for patient and hospital characteristics were used to evaluate mortality and readmission outcomes.ResultsA cohort of 86,659 HF patients aged ≥65 years was followed for 3 years from discharge. Unadjusted all-cause mortality was between 4.4% and 5.5% and all-cause hospitalization was between 19.4% and 22.6% for all groups at 30 days. For all-cause mortality at 3 years from hospital discharge, diabetes was associated with an adjusted hazard ratio of 1.27 (95% CI 1.07-1.49, P = .0051) for HFrEF, 0.95 (95% CI 0.55-1.65, P = .8536) for HFbEF, 1.02 (95% CI 0.87-1.19, P = .8551) for HFpEF. For all-cause readmission, diabetes was associated with an adjusted hazard ratio of 1.06 (95% CI 0.87-1.29, P = .5585) for HFrEF, 1.48 (95% CI 1.15-1.90, P = .0023) for HFbEF, and 1.06 (95% CI 0.91-1.22, P = .4747) for HFpEF.ConclusionsHFrEF and HFbEF patients with diabetes are at increased risk for mortality and rehospitalization after hospitalization for HF, independent of other patient and hospital characteristics. Among HFpEF patients, diabetes does not appear to be independently associated with significant additional risks