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Background

The onset of acute heart failure is known to be associated with increased physical activity and other specific behaviors that can trigger hemodynamic deterioration. This analysis aimed to describe the distribution of triggers in patients hospitalized for acute heart failure, and investigate their effects on in-hospital outcomes.

Methods

Consecutive patients hospitalized for acute heart failure between 2010 and 2014 were registered in a multicenter data registration system (72 institutions within Tokyo, Japan). Baseline demographics and in-hospital mortality were extracted from 17,473 patients. Patients with a trigger were grouped based on their triggering event: those with onset during (a) physical activity; (b) sleeping; (c) eating or watching television; (d) bathing or excretion (use of restrooms); and (e) engaging in other activities. These patients were compared with patients without identifiable triggers. Multiple imputation was used for missing data.

Results

Patients were predominantly men (57.1%), with a mean age of 76.0 ± 13.0 years; a triggering event was present in 49.1%. No significant difference in baseline characteristics was noted between groups except for younger age, higher blood pressure, and prevalence of signs of congestion in the trigger-positive group. In-hospital mortality rate was 7.9%. Presence of triggers was positively associated with a reduced risk of in-hospital mortality (adjusted odds ratio 0.79; 95% confidence interval, 0.70-0.90; P = .0003). In a delta-adjusted pattern mixture model, the effect of a triggering event on in-hospital mortality remained consistently significant.

Conclusion

Triggering events for acute heart failure can provide additional information for risk prediction. Efforts to identify the triggers should be made to classify patients according to risk group.  相似文献   
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OBJECTIVE: Despite multiple and repeated exposures to HIV-1, some individuals possess no detectable HIV genome and show T-cell memory responses to the viral antigens. HIV-1-reactive mucosal IgA detected in such uninfected individuals suggests their possible immune resistance against HIV. We tested if the above HIV-1-exposed but uninfected status was associated with genetic markers other than a homozygous deletion of the CCR5 gene. METHODS: Based on our mapping in chromosome 15 of a gene controlling the production of neutralizing antibodies in a mouse retrovirus infection, we genotyped 42 HIV-1-exposed but uninfected Italians at polymorphic loci in the syntenic segment of human chromosome 22, and compared them with 49 HIV-1-infected and 47 uninfected healthy control individuals by a closed testing procedure. RESULTS: A significant association was found between chromosome 22q12-13 genotypes and a putative dominant locus conferring anti-HIV-1 immune responses in the exposed but uninfected individuals. Distributions of linkage disequilibrium across chromosome 22 also differed between the exposed but uninfected and two other phenotypic groups. CONCLUSIONS: The data indicated the presence of a new genetic factor associated with the HIV-1-exposed but uninfected status.  相似文献   
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Adult mouse natural killer (NK) cells express two families of MHC class I-specific receptors, namely Ly49 and CD94/NKG2, whereas fetal and neonatal NK cells express only CD94/NKG2. After birth, Ly49(+) NK cells slowly increase and CD94/NKG2(+) NK cells decrease. The aim of this study was to determine whether murine NK cells develop differently from transplants of fetal liver and adult marrow stem cells and whether the adult marrow microenvironment is critical for NK receptor maturation. Enriched populations of stem cells were transplanted into adult mice, and the kinetics of NK receptor acquisition was examined. NK cells from osteopetrotic Csf1(op)/Csf1(op) mice, in which hematopoiesis within the marrow is severely limited, were also analyzed.NK cells regenerated from both fetal and adult stem cells initially resembled neonatal NK cells in their slow acquisition of Ly49 over several weeks, although the adult stem cell-derived NK cells matured approximately 10 days sooner. NK cells from adult Csf1(op)/Csf1(op) mice expressed normal levels of Ly49. Maturation of the NK receptor repertoire is a slow process regardless of their stem cell origin or reduced marrow space caused by osteopetrosis.  相似文献   
45.
We tested the hypothesis that the environmental noise generated by a forced-air warming system reduces the monitoring accuracy of acoustic respiration rate (RRa). Noise levels were adjusted to 45–55, 56–65, 66–75, and 76–85 dB. Healthy participants breathed at set respiration rates (RRset) of 6, 12, and 30/min. Under each noise level at each RRset, the respiration rates by manual counting (RRm) and RRa were recorded. Any appearance of the alarm display on the RRa monitor was also recorded. Each RRm of all participants agreed with each RRset at each noise level. At 45–55 dB noise, the RRa of 13, 17, and 17 participants agreed with RRset of 6, 12, and 30/min, respectively. The RRa of 14, 17, and 16 participants at 56–65 dB noise, agreed with RRset of 6, 12, and 30/min, respectively. At 66–75 dB noise, the RRa of 9, 15, and 16 participants agreed with RRset of 6, 12, and 30/min, respectively. The RRa of one, nine, and nine participants at 76–85 dB noise agreed with RRset of 6, 12, and 30/min, respectively, which was significantly less than the other noise levels (P?<?0.05). Overall, 72.9% of alarm displays highlighted incorrect values of RRa. In a noisy situation involving the operation of a forced-air warming system, the acoustic respiration monitoring should be used carefully especially in patients with a low respiration rate.  相似文献   
46.
Clinical Rheumatology - Cryopyrin-associated periodic fever syndrome (CAPS) is a highly debilitating disorder, which is characterized by unregulated interleukin-1β production driven by...  相似文献   
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Natriuretic peptides (NPs) play important roles in osmoregulatory and cardiovascular systems of vertebrates. For functional studies of NPs, rainbow trout (Oncorhynchus mykiss), a euryhaline fish, is an interesting model. The information on homologous NPs of salmonid fish is, however, still incomplete with respect to C-type NP (CNP). In this study, we isolated cDNAs encoding the precursor of CNP from the brain of trout. Predicted mature CNP (CNP-22) sequence was identical to that of killifish Fundulus heteroclitus, and only one amino acid was different from that of the eel Anguilla japonica, demonstrating a greater conservation among different teleost species than is found with atrial NP (ANP) and ventricular NP (VNP). While the preprosegment of trout CNP retained 57% similarity to the eel sequence, similarities were low to those of sharks and tetrapods. The major site of expression identified by RT-PCR was the brain with minor expression in the atrium. The putative mature CNP-22 was synthesized and its biological activity was compared with other trout NPs (ANP and VNP) using trout ventral aorta, efferent branchial and celiacomesenteric arteries and anterior cardinal vein in vitro. Synthetic trout CNP-22 relaxed all pre-contracted vessels with potencies comparable to trout ANP and VNP.  相似文献   
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