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11.
Paced QRS morphology predicts incident left ventricular systolic dysfunction and atrial fibrillation
Martin van Zyl Chance M. Witt Subir Bhatia Majd Khasawneh Prakriti Gaba Charles J. Lenz Andrew N. Rosenbaum Htin Aung David O. Hodge Christopher J. McLeod Samuel J. Asirvatham 《Indian pacing and electrophysiology journal》2019,19(2):40-46
Background
The prognostic significance of paced QRS complex morphology on surface ECG remains unclear. This study aimed to assess long-term outcomes associated with variations in the paced QRS complex.Methods
Adult patients who underwent dual-chamber pacemaker implantation with 20% or more ventricular pacing and a 12-lead ECG showing a paced complex were included. The paced QRS was analyzed in leads I and aVL. Long-term clinical and echocardiographic outcomes were compared at 5 years.Results
The study included 844 patients (43.1% female; age 75.0?±?12.1). Patients with a longer paced QRS (pQRS) duration in lead I had a lower rate of atrial fibrillation (HR 0.80; p?=?0.03) and higher rate of systolic dysfunction (HR 1.17; p?<?0.001). Total pacing complex (TPC) duration was linked to higher rates of ICD implantation (HR 1.18; p?=?0.04) and systolic dysfunction (HR 1.22, p?<?0.001). Longer paced intrinsicoid deflection (pID) was associated with less atrial fibrillation (HR 0.75; p?=?0.01), more systolic dysfunction (HR 1.17; p?<?0.001), ICD implantation (HR 1.23; p?=?0.04), and CRT upgrade (HR 1.23; p?=?0.03). Exceeding thresholds for TPC, pQRS, and pID of 170, 146, and 112?ms in lead I, respectively, was associated with a substantial increase in systolic dysfunction over 5 years (p?<?0.001).Conclusions
Longer durations of all tested parameters in lead I were associated with increased rates of left ventricular systolic dysfunction. ICD implantation and CRT upgrade were also linked to increased TPC and pID durations. Paradoxically, patients with longer pID and pQRS had less incident atrial fibrillation. 相似文献12.
J?Craig CohenEmail author Lennart?KA?Lundblad Jason?HT?Bates Michael?Levitzky Janet?E?Larson 《BMC genetics》2004,5(1):21
Background
Cystic Fibrosis is a pleiotropic disease in humans with primary morbidity and mortality associated with a lung disease phenotype. However, knockout in the mouse of cftr, the gene whose mutant alleles are responsible for cystic fibrosis, has previously failed to produce a readily, quantifiable lung phenotype. 相似文献13.
Aung T Ocaka L Ebenezer ND Morris AG Brice G Child AH Hitchings RA Lehmann OJ Bhattacharya SS 《Human genetics》2002,110(5):513-514
OPA1, the gene responsible for autosomal dominant optic atrophy, represents a good candidate gene for glaucoma, as there are similarities in the clinical phenotype and OPA1 is expressed in the optic nerve. Single nucleotide polymorphisms on intervening sequence (IVS) 8 of the OPA1gene (genotype IVS8+4 C/T;+32T/C) were recently found to be strongly associated with normal tension glaucoma (NTG). In order to investigate whether this association exists in patients with high-tension glaucoma (HTG), 90 well-characterized HTG patients were examined for the presence of these OPA1polymorphisms by PCR amplification followed by bi-directional sequencing. Five out of 90 HTG subjects (5.6%; 95% CI 1.8-12.5) were found to carry the OPA1 genotype IVS 8+4 C/T; +32 T/C, compared with 32/163 (19.6%; 95% CI 13.8-26.6) NTG subjects [chi(2)=9.2, P=0.002, OR 4.1 (95% CI 1.6-11.1)], and 7/186 (3.8%; 95% CI 1.5-7.6) control subjects [chi(2)=0.47, P=0.49, OR 1.5 (95% CI 0.5-4.9)]. These results indicate that unlike NTG, the OPA1 genotype IVS8+4 C/T,+32T/C is not significantly associated with high-tension primary open angle glaucoma, and suggest genetic heterogeneity between the conditions. 相似文献
14.
IL-4 diminishes perforin-mediated and increases Fas ligand-mediated cytotoxicity In vivo 总被引:5,自引:0,他引:5
CTL have evolved two major mechanisms for target cell killing: one mediated by perforin/granzyme secretion and the other by Fas/Fas ligand (L) interaction. Although cytokines are integral to the development of naive CTL into cytolytic effectors, the role of cytokines on mechanisms of CTL killing is just emerging. In this study, we evaluate the effects of IL-4 in Fas(CD95)/FasL(CD95L)-mediated killing of Fas-overexpressing target cells. Recombinant vaccinia viruses (vv) were constructed to express respiratory syncytial virus M2 Ag alone (vvM2) or coexpress M2 and IL-4 (vvM2/IL-4). MHC-matched Fas-overexpressing target cells (L1210Fas+) were used to measure both perforin- and FasL-mediated killing pathways. In contrast to Fas-deficient (L1210Fas-) target cells, effectors from vvM2/IL-4-immunized mice were able to lyse L1210Fas+ target cells with similar magnitude as vvM2-infected mice. Addition of EGTA/Mg2+ revealed that effectors from vvM2/IL-4-infected mice primarily lyse targets by a Ca2+-independent Fas/FasL pathway. Analysis of FasL expression by flow cytometry showed that IL-4 increased cell surface FasL expression on CD4+ and CD8+ splenocytes, with peak expression on day 4 after infection. These data demonstrate that IL-4 increases FasL expression on T cells, resulting in a shift of the mechanism of CTL killing from a dominant perforin-mediated cytolytic pathway to a dominant FasL-mediated cytolytic pathway. 相似文献
15.
16.
Elaine W. Chong Yuanyuan Wang Liubov D. Robman Khin Zaw Aung Galina A. Makeyeva Graham G. Giles Stephen Graves Flavia M. Cicuttini Robyn H. Guymer 《PloS one》2015,10(9)
Osteoarthritis is the leading cause of total hip replacement, accounting for more than 80% of all total hip replacements. Emerging evidence suggests that osteoarthritis has a chronic inflammatory component to its pathogenesis similar to age-related macular degeneration. We evaluated the association between age-related macular degeneration and total hip replacement as proxy for severe osteoarthritis or fractured neck of femur in the Melbourne Collaborative Cohort Study. 20,744 participants had complete data on both age-related macular degeneration assessed from colour fundus photographs taken during 2003–2007 and total hip replacement. Total hip replacements due to hip osteoarthritis and fractured neck of femur during 2001–2011 were identified by linking the cohort records to the Australian Orthopedic Association National Joint Replacement Registry. Logistic regression was used to examine the association between age-related macular degeneration and risk of total hip replacement due to osteoarthritis and fracture separately, adjusted for confounders. There were 791 cases of total hip replacement for osteoarthritis and 102 cases of total hip replacement due to fractured neck of femur. After adjustment for age, sex, body mass index, smoking, and grouped country of birth, intermediate age-related macular degeneration was directly associated with total hip replacement for osteoarthritis (odds ratio 1.22, 95% CI 1.00–1.49). Late age-related macular degeneration was directly associated with total hip replacement due to fractured neck of femur (odds ratio 5.21, 95% CI2.25–12.02). The association between intermediate age-related macular degeneration and an increased 10-year incidence of total hip replacement due to osteoarthritis suggests the possibility of similar inflammatory processes underlying both chronic diseases. The association of late age-related macular degeneration with an increased 10-year incidence of total hip replacement due to fractured neck of femur may be due to an increased prevalence of fractures in those with poor central vision associated with the late complications of age-related macular degeneration. 相似文献
17.
18.
Iris M Costa Tallybia HT Nasser Marilene Demasi Rafaella MP Nascimento Luis ES Netto Sayuri Miyamoto Fernanda M Prado Gisele Monteiro 《BMC microbiology》2011,11(1):268
Background
The gene YCL047C, which has been renamed promoter of filamentation gene (POF1), has recently been described as a cell component involved in yeast filamentous growth. The objective of this work is to understand the molecular and biological function of this gene.Results
Here, we report that the protein encoded by the POF1 gene, Pof1p, is an ATPase that may be part of the Saccharomyces cerevisiae protein quality control pathway. According to the results, Δpof1 cells showed increased sensitivity to hydrogen peroxide, tert-butyl hydroperoxide, heat shock and protein unfolding agents, such as dithiothreitol and tunicamycin. Besides, the overexpression of POF1 suppressed the sensitivity of Δpct1, a strain that lacks a gene that encodes a phosphocholine cytidylyltransferase, to heat shock. In vitro analysis showed, however, that the purified Pof1p enzyme had no cytidylyltransferase activity but does have ATPase activity, with catalytic efficiency comparable to other ATPases involved in endoplasmic reticulum-associated degradation of proteins (ERAD). Supporting these findings, co-immunoprecipitation experiments showed a physical interaction between Pof1p and Ubc7p (an ubiquitin conjugating enzyme) in vivo.Conclusions
Taken together, the results strongly suggest that the biological function of Pof1p is related to the regulation of protein degradation.19.
BACKGROUND: Quality is central to understanding provider motivations to join and remain within a social franchising network. Quality also appears as a key issue from the client's perspective, and may influence why a client chooses to use a franchised provider over another type of provider. The dynamic relationships between providers of social franchising clinics and clients who use these services have not been thoroughly investigated in the context of Myanmar, which has an established social franchising network. This study examines client motivations to use a Sun Quality Health network provider and provider motivations to join and remain in the Sun Quality Health network. Taken together, these two aims provide an opportunity to explore the symbiotic relationship between client satisfaction and provider incentives to increase the utilization of reproductive health care services. METHODS AND FINDINGS: Results from a series of focus group discussions with clients of reproductive health services and franchised providers shows that women chose health services provided by franchised private sector general practitioners because of its perceived higher quality, associated with the availability of effective, affordable, drugs. A key finding of the study is associated with providers. Provider focus group discussions indicate that a principle determinate for joining and remaining in the Sun Quality Health Network was serving the poor. 相似文献
20.