706,784 research outputs found

    Gastrointestinal tract size, total-tract digestibility, and rumen microflora in different dairy cow genotypes

    Get PDF
    peer-reviewedThe superior milk production efficiency of Jersey (JE) and Jersey × Holstein-Friesian (JE × HF) cows compared with Holstein-Friesian (HF) has been widely published. The biological differences among dairy cow genotypes, which could contribute to the milk production efficiency differences, have not been as widely studied however. A series of component studies were conducted using cows sourced from a longer-term genotype comparison study (JE, JE × HF, and HF). The objectives were to (1) determine if differences exist among genotypes regarding gastrointestinal tract (GIT) weight, (2) assess and quantify whether the genotypes tested differ in their ability to digest perennial ryegrass, and (3) examine the relative abundance of specific rumen microbial populations potentially relating to feed digestibility. Over 3 yr, the GIT weight was obtained from 33 HF, 35 JE, and 27 JE × HF nonlactating cows postslaughter. During the dry period the cows were offered a perennial ryegrass silage diet at maintenance level. The unadjusted GIT weight was heavier for the HF than for JE and JE × HF. When expressed as a proportion of body weight (BW), JE and JE × HF had a heavier GIT weight than HF. In vivo digestibility was evaluated on 16 each of JE, JE × HF, and HF lactating dairy cows. Cows were individually stalled, allowing for the total collection of feces and were offered freshly cut grass twice daily. During this time, daily milk yield, BW, and dry matter intake (DMI) were greater for HF and JE × HF than for JE; milk fat and protein concentration ranked oppositely. Daily milk solids yield did not differ among the 3 genotypes. Intake capacity, expressed as DMI per BW, tended to be different among treatments, with JE having the greatest DMI per BW, HF the lowest, and JE × HF being intermediate. Production efficiency, expressed as milk solids per DMI, was higher for JE than HF and JE × HF. Digestive efficiency, expressed as digestibility of dry matter, organic matter, N, neutral detergent fiber, and acid detergent fiber, was higher for JE than HF. In grazing cows (n = 15 per genotype) samples of rumen fluid, collected using a transesophageal sampling device, were analyzed to determine the relative abundance of rumen microbial populations of cellulolytic bacteria, protozoa, and fungi. These are critically important for fermentation of feed into short-chain fatty acids. A decrease was observed in the relative abundance of Ruminococcus flavefaciens in the JE rumen compared with HF and JE × HF. We can deduce from this study that the JE genotype has greater digestibility and a different rumen microbial population than HF. Jersey and JE × HF cows had a proportionally greater GIT weight than HF. These differences are likely to contribute to the production efficiency differences among genotypes previously reported

    Duration of chronic heart failure affects outcomes with preserved effects of heart rate reduction with ivabradine: findings from SHIFT

    Get PDF
    Aims: In heart failure (HF) with reduced ejection fraction and sinus rhythm, heart rate reduction with ivabradine reduces the composite incidence of cardiovascular death and HF hospitalization. Methods and results: It is unclear whether the duration of HF prior to therapy independently affects outcomes and whether it modifies the effect of heart rate reduction. In SHIFT, 6505 patients with chronic HF (left ventricular ejection fraction of ≤35%), in sinus rhythm, heart rate of ≥70 b.p.m., treated with guideline-recommended therapies, were randomized to placebo or ivabradine. Outcomes and the treatment effect of ivabradine in patients with different durations of HF were examined. Prior to randomization, 1416 ivabradine and 1459 placebo patients had HF duration of ≥4 weeks and <1.5 years; 836 ivabradine and 806 placebo patients had HF duration of 1.5 years to <4 years, and 989 ivabradine and 999 placebo patients had HF duration of ≥4 years. Patients with longer duration of HF were older (62.5 years vs. 59.0 years; P < 0.0001), had more severe disease (New York Heart Association classes III/IV in 56% vs. 44.9%; P < 0.0001) and greater incidences of co-morbidities [myocardial infarction: 62.9% vs. 49.4% (P < 0.0001); renal dysfunction: 31.5% vs. 21.5% (P < 0.0001); peripheral artery disease: 7.0% vs. 4.8% (P < 0.0001)] compared with patients with a more recent diagnosis. After adjustments, longer HF duration was independently associated with poorer outcome. Effects of ivabradine were independent of HF duration. Conclusions: Duration of HF predicts outcome independently of risk indicators such as higher age, greater severity and more co-morbidities. Heart rate reduction with ivabradine improved outcomes independently of HF duration. Thus, HF treatments should be initiated early and it is important to characterize HF populations according to the chronicity of HF in future trials

    Dynamic changes and prognostic value of pulmonary congestion by lung ultrasound in acute and chronic heart failure: a systematic review

    Get PDF
    Aims: Pulmonary congestion is an important finding in patients with heart failure (HF) that can be quantified by lung ultrasound (LUS). We conducted a systematic review to describe dynamic changes in LUS findings of pulmonary congestion (B-lines) in HF and to examine the prognostic utility of B-lines in HF. Methods and results: We searched online databases for studies conducted in patients with chronic or acute HF that used LUS to assess dynamic changes or the prognostic value of pulmonary congestion. We included studies in adult populations, published in English, and conducted in ≥25 patients. Of 1327 identified studies, 13 (25–290 patients) met the inclusion criteria: six reported on dynamic changes in LUS findings (438 patients) and seven on the prognostic value of B-lines in HF (953 patients). In acute HF, B-line number changed within as few as 3 h of HF treatment. In acute HF, ≥15 B-lines on 28-zone LUS at discharge identified patients at a more than five-fold risk for HF readmission or death. Similarly, in ambulatory patients with chronic HF, ≥3 B-lines on five- or eight-zone LUS marked those at a nearly four-fold risk for 6-month HF hospitalization or death. Conclusions: Lung ultrasound findings change rapidly in response to HF therapy. This technique may represent a useful and non-invasive method to track dynamic changes in pulmonary congestion. Furthermore, residual congestion at the time of discharge in acute HF or in ambulatory patients with chronic HF may identify those at high risk for adverse events

    Characteristics of patients with haematological and breast cancer (1996–2009) who died of heart failure-related causes after cancer therapy

    Get PDF
    Aims: To describe the characteristics and time to death of patients with breast or haematological cancer who died of heart failure (HF) after cancer therapy. Patients with an index admission for HF who died of HF-related causes (IAHF) and those with no index admission for HF who died of HF-related causes (NIAHF) were compared. Methods and results: We performed a linked data analysis of cancer registry, death registry, and hospital administration records (n = 15 987). Index HF admission must have occurred after cancer diagnosis. Of the 4894 patients who were deceased (30.6% of cohort), 734 died of HF-related causes (50.1% female) of which 279 (38.0%) had at least one IAHF (41.9% female) post-cancer diagnosis. Median age was 71 years [interquartile range (IQR) 62–78] for IAHF and 66 years (IQR 56–74) for NIAHF. There were fewer chemotherapy separations for IAHF patients (median = 4, IQR 2–9) compared with NIAHF patients (median = 6, IQR 2–12). Of the IAHF patients, 71% had died within 1 year of the index HF admission. There was no significant difference in HF-related mortality in IAHF patients compared with NIAHF (HR, 1.10, 95% CI, 0.94–1.29, P = 0.225). Conclusions: The profile of IAHF patients who died of HF-related causes after cancer treatment matched the current profile of HF in the general population (over half were aged ≥70 years). However, NIAHF were younger (62% were aged ≤69 years), female patients with breast cancer that died of HF-related causes before hospital admission for HF-related causes—a group that may have been undiagnosed or undertreated until death

    Examining mortality among formerly homeless adults enrolled in Housing First: An observational study

    Get PDF
    BACKGROUND: Adults who experience prolonged homelessness have mortality rates 3 to 4 times that of the general population. Housing First (HF) is an evidence-based practice that effectively ends chronic homelessness, yet there has been virtually no research on premature mortality among HF enrollees. In the United States, this gap in the literature exists despite research that has suggested chronically homeless adults constitute an aging cohort, with nearly half aged 50 years old or older. METHODS: This observational study examined mortality among formerly homeless adults in an HF program. We examined death rates and causes of death among HF participants and assessed the timing and predictors of death among HF participants following entry into housing. We also compared mortality rates between HF participants and (a) members of the general population and (b) individuals experiencing homelessness. We supplemented these analyses with a comparison of the causes of death and characteristics of decedents in the HF program with a sample of adults identified as homeless in the same city at the time of death through a formal review process. RESULTS: The majority of decedents in both groups were between the ages of 45 and 64 at their time of death; the average age at death for HF participants was 57, compared to 53 for individuals in the homeless sample. Among those in the HF group, 72 % died from natural causes, compared to 49 % from the homeless group. This included 21 % of HF participants and 7 % from the homeless group who died from cancer. Among homeless adults, 40 % died from an accident, which was significantly more than the 14 % of HF participants who died from an accident. HIV or other infectious diseases contributed to 13 % of homeless deaths compared to only 2 % of HF participants. Hypothermia contributed to 6 % of homeless deaths, which was not a cause of death for HF participants. CONCLUSIONS: Results suggest HF participants face excess mortality in comparison to members of the general population and that mortality rates among HF participants are higher than among those reported among members of the general homeless population in prior studies. However, findings also suggest that causes of death may differ between HF participants and their homeless counterparts. Specifically, chronic diseases appear to be more prominent causes of death among HF participants, indicating the potential need for integrating medical support and end-of-life care in HF

    Hydrogen Fluoride in High-Mass Star-forming Regions

    Get PDF
    Hydrogen fluoride has been established to be an excellent tracer of molecular hydrogen in diffuse clouds. In denser environments, however, the HF abundance has been shown to be approximately two orders of magnitude lower. We present Herschel/HIFI observations of HF J=1-0 toward two high-mass star formation sites, NGC6334 I and AFGL 2591. In NGC6334 I the HF line is seen in absorption in foreground clouds and the source itself, while in AFGL 2591 HF is partially in emission. We find an HF abundance with respect to H2 of 1.5e-8 in the diffuse foreground clouds, whereas in the denser parts of NGC6334 I, we derive a lower limit on the HF abundance of 5e-10. Lower HF abundances in dense clouds are most likely caused by freeze out of HF molecules onto dust grains in high-density gas. In AFGL 2591, the view of the hot core is obstructed by absorption in the massive outflow, in which HF is also very abundant 3.6e-8) due to the desorption by sputtering. These observations provide further evidence that the chemistry of interstellar fluorine is controlled by freeze out onto gas grains.Comment: accepted in Ap

    Disordered mesoscopic systems with interactions: induced two-body ensembles and the Hartree-Fock approach

    Full text link
    We introduce a generic approach to study interaction effects in diffusive or chaotic quantum dots in the Coulomb blockade regime. The randomness of the single-particle wave functions induces randomness in the two-body interaction matrix elements. We classify the possible induced two-body ensembles, both in the presence and absence of spin degrees of freedom. The ensembles depend on the underlying space-time symmetries as well as on features of the two-body interaction. Confining ourselves to spinless electrons, we then use the Hartree-Fock (HF) approximation to calculate HF single-particle energies and HF wave functions for many realizations of the ensemble. We study the statistical properties of the resulting one-body HF ensemble for a fixed number of electrons. In particular, we determine the statistics of the interaction matrix elements in the HF basis, of the HF single-particle energies (including the HF gap between the last occupied and the first empty HF level), and of the HF single-particle wave functions. We also study the addition of electrons, and in particular the distribution of the distance between successive conductance peaks and of the conductance peak heights.Comment: 25 pages, 16 figure

    Influence of Sacubitril/Valsartan (LCZ696) on 30-day readmission after heart failure hospitalization

    Get PDF
    Background: Patients with heart failure (HF) are at high risk for hospital readmission in the first 30 days following HF hospitalization. Objectives: This study sought to determine if treatment with sacubitril/valsartan (LCZ696) reduces rates of hospital readmission at 30-days following HF hospitalization compared with enalapril. Methods: We assessed the risk of 30-day readmission for any cause following investigator-reported hospitalizations for HF in the PARADIGM-HF trial, which randomized 8,399 participants with HF and reduced ejection fraction to treatment with LCZ696 or enalapril. Results: Accounting for multiple hospitalizations per patient, there were 2,383 investigator-reported HF hospitalizations, of which 1,076 (45.2%) occurred in subjects assigned to LCZ696 and 1,307 (54.8%) occurred in subjects assigned to enalapril. Rates of readmission for any cause at 30 days were 17.8% in LCZ696-assigned subjects and 21.0% in enalapril-assigned subjects (odds ratio: 0.74; 95% confidence interval: 0.56 to 0.97; p = 0.031). Rates of readmission for HF at 30-days were also lower in subjects assigned to LCZ696 (9.7% vs. 13.4%; odds ratio: 0.62; 95% confidence interval: 0.45 to 0.87; p = 0.006). The reduction in both all-cause and HF readmissions with LCZ696 was maintained when the time window from discharge was extended to 60 days and in sensitivity analyses restricted to adjudicated HF hospitalizations. Conclusions: Compared with enalapril, treatment with LCZ696 reduces 30-day readmissions for any cause following discharge from HF hospitalization
    corecore