248 research outputs found
Common conditions associated with hereditary haemochromatosis genetic variants: cohort study in UK Biobank
This is the final published version. Available from BMJ publishing group via the DOI in this record.Data are available on application to the UK Biobank (www.ukbiobank.ac.uk/register-apply).Objective To compare prevalent and incident morbidity and mortality between those with the HFE p.C282Y genetic variant (responsible for most hereditary haemochromatosis type 1) and those with no p.C282Y mutations, in a large UK community sample of European descent.
Design Cohort study.
Setting 22 centres across England, Scotland, and Wales in UK Biobank (2006-10).
Participants 451â243 volunteers of European descent aged 40 to 70 years, with a mean follow-up of seven years (maximum 9.4 years) through hospital inpatient diagnoses and death certification.
Main outcome measure Odds ratios and Cox hazard ratios of disease rates between participants with and without the haemochromatosis mutations, adjusted for age, genotyping array type, and genetic principal components. The sexes were analysed separately as morbidity due to iron excess occurs later in women.
Results Of 2890 participants homozygous for p.C282Y (0.6%, or 1 in 156), haemochromatosis was diagnosed in 21.7% (95% confidence interval 19.5% to 24.1%, 281/1294) of men and 9.8% (8.4% to 11.2%, 156/1596) of women by end of follow-up. p.C282Y homozygous men aged 40 to 70 had a higher prevalence of diagnosed haemochromatosis (odds ratio 411.1, 95% confidence interval 299.0 to 565.3, P<0.001), liver disease (4.30, 2.97 to 6.18, P<0.001), rheumatoid arthritis (2.23, 1.51 to 3.31, P<0.001), osteoarthritis (2.01, 1.71 to 2.36, P<0.001), and diabetes mellitus (1.53, 1.16 to 1.98, P=0.002), versus no p.C282Y mutations (n=175â539). During the seven year follow-up, 15.7% of homozygous men developed at least one incident associated condition versus 5.0% (P<0.001) with no p.C282Y mutations (women 10.1% v 3.4%, P<0.001). Haemochromatosis diagnoses were more common in p.C282Y/p.H63D heterozygotes, but excess morbidity was modest.
Conclusions In a large community sample, HFE p.C282Y homozygosity was associated with substantial prevalent and incident clinically diagnosed morbidity in both men and women. As p.C282Y associated iron overload is preventable and treatable if intervention starts early, these findings justify re-examination of options for expanded early case ascertainment and screening.Medical Research Council (MRC)University of Exeter Medical SchoolUniversity of Conneticut Health CentreNational Centre for AgeingPublic Health Englan
Outcomes of Treated Hypertension at Age 80 and Older: Cohort Analysis of 79,376 Individuals
This is the final version of the article. Available from Wiley via the DOI in this record.OBJECTIVES: To estimate outcomes according to
attained blood pressure (BP) in the oldest adults treated
for hypertension in routine family practice.
DESIGN: Cohort analysis of primary care inpatient and
death certificate data for individuals with hypertension.
SETTING: Primary care practices in England (Clinical
Practice Research Datalink).
PARTICIPANTS: Individuals aged 80 and older taking
antihypertensive medication and free of dementia, cancer,
coronary heart disease, stroke, heart failure, and end-stage
renal failure at baseline.
MEASUREMENTS: Outcomes were mortality, cardiovascular
events, and fragility fractures. Systolic BP (SBP) was
grouped in 10-mmHg increments from less than 125 to
185 mmHg or more (reference 145â154 mmHg).
RESULTS: Myocardial infarction hazards increased linearly
with increasing SBP, and stroke hazards increased for
SBP of 145 mmHg or greater, although lowest mortality
was in individuals with SBP of 135 to 154 mmHg. Mortality
of the 13.1% of patients with SBP less than 135 mmHg
was higher than that of the reference group (Cox hazard
ratio=1.25, 95% confidence interval=1.19â1.31; equating
to one extra death per 12.6 participants). This difference
in mortality was consistent over short- and long-term follow-up;
adjusting for diastolic BP did not change the risk. Incident heart failure rates were higher in those with SBP
less than 125 mmHg than in the reference group.
CONCLUSION: In routine primary care, SBP less than
135 mmHg was associated with greater mortality in the
oldest adults with hypertension and free of selected potentially
confounding comorbidities. Although important confounders
were accounted for, observational studies cannot
exclude residual confounding. More work is needed to
establish whether unplanned SBPs less than 135 mmHg in
older adults with hypertension may be a useful clinical
sign of poor prognosis, perhaps requiring clinical review of
overall care.This work was supported in part by
the National Institute for Health Research (NIHR) School
for Public Health Research Ageing Well programme
Mid-life Leukocyte Telomere Length and Dementia Risk: An Observational and Mendelian Randomization Study of 435,046 UK Biobank Participants
Telomere attrition is one of biological aging hallmarks and may be intervened to target multiple aging-related diseases, including Alzheimer\u27s disease and Alzheimer\u27s disease related dementias (AD/ADRD). The objective of this study was to assess associations of leukocyte telomere length (TL) with AD/ADRD and early markers of AD/ADRD, including cognitive performance and brain magnetic resonance imaging (MRI) phenotypes. Data from European-ancestry participants in the UK Biobank (n =â435,046) were used to evaluate whether mid-life leukocyte TL is associated with incident AD/ADRD over a mean follow-up of 12.2âyears. In a subsample without AD/ADRD and with brain imaging data (n =â43,390), we associated TL with brain MRI phenotypes related to AD or vascular dementia pathology. Longer TL was associated with a lower risk of incident AD/ADRD (adjusted Hazard Ratio [aHR] per SD = 0.93, 95% CI 0.90â0.96, p =â3.37âĂâ10â7). Longer TL also was associated with better cognitive performance in specific cognitive domains, larger hippocampus volume, lower total volume of white matter hyperintensities, and higher fractional anisotropy and lower mean diffusivity in the fornix. In conclusion, longer TL is inversely associated with AD/ADRD, cognitive impairment, and brain structural lesions toward the development of AD/ADRD. However, the relationships between genetically determined TL and the outcomes above were not statistically significant based on the results from Mendelian randomization analysis results. Our findings add to the literature of prioritizing risk for AD/ADRD. The causality needs to be ascertained in mechanistic studies
Sestrins induce natural killer function in senescent-like CD8(+) T cells
Aging is associated with remodeling of the immune system to enable the maintenance of life-long immunity. In the CD8âș T cell compartment, aging results in the expansion of highly differentiated cells that exhibit characteristics of cellular senescence. Here we found that CD27â»CD28â»CD8âș T cells lost the signaling activity of the T cell antigen receptor (TCR) and expressed a protein complex containing the agonistic natural killer (NK) receptor NKG2D and the NK adaptor molecule DAP12, which promoted cytotoxicity against cells that expressed NKG2D ligands. Immunoprecipitation and imaging cytometry indicated that the NKG2D-DAP12 complex was associated with sestrin 2. The genetic inhibition of sestrin 2 resulted in decreased expression of NKG2D and DAP12 and restored TCR signaling in senescent-like CD27â»CD28â»CD8âș T cells. Therefore, during aging, sestrins induce the reprogramming of non-proliferative senescent-like CD27â»CD28â»CD8âș T cells to acquire a broad-spectrum, innate-like killing activity
Life\u27s Essential 8: Optimizing Health in Older Adults
The population worldwide is getting older as a result of advances in public health, medicine, and technology. Older individuals are living longer with a higher prevalence of subclinical and clinical cardiovascular disease (CVD). In 2010, the American Heart Association introduced a list of key prevention targets, known as Life\u27s Simple 7 to increase CVD-free survival, longevity, and quality of life. In 2022, sleep health was added to expand the recommendations to Life\u27s Essential 8 (eat better, be more active, stop smoking, get adequate sleep, manage weight, manage cholesterol, manage blood pressure, and manage diabetes). These prevention targets are intended to apply regardless of chronologic age. During this same time, the understanding of aging biology and goals of care for older adults further enhanced the relevance of prevention across the range of functions. From a biological perspective, aging is a complex cellular process characterized by genomic instability, telomere attrition, loss of proteostasis, inflammation, deregulated nutrient-sensing, mitochondrial dysfunction, cellular senescence, stem cell exhaustion, and altered intercellular communication. These aging hallmarks are triggered by and enhanced by traditional CVD risk factors leading to geriatric syndromes (eg, frailty, sarcopenia, functional limitation, and cognitive impairment) which complicate efforts toward prevention. Therefore, we review Life\u27s Essential 8 through the lens of aging biology, geroscience, and geriatric precepts to guide clinicians taking care of older adults
Null mutation for Macrophage Migration Inhibitory Factor (MIF) is associated with less aggressive bladder cancer in mice
<p>Abstract</p> <p>Background</p> <p>Inflammatory cytokines may promote tumorigenesis. Macrophage migration inhibitory factor (MIF) is a proinflammatory cytokine with regulatory properties over tumor suppressor proteins involved in bladder cancer. We studied the development of bladder cancer in wild type (WT) and MIF knockout (KO) mice given N-butyl-N-(4-hydroxybutyl)-nitrosamine (BBN), a known carcinogen, to determine the role of MIF in bladder cancer initiation and progression.</p> <p>Methods</p> <p>5-month old male C57Bl/6 MIF WT and KO mice were treated with and without BBN. Animals were sacrificed at intervals up to 23 weeks of treatment. Bladder tumor stage and grade were evaluated by H&E. Immunohistochemical (IHC) analysis was performed for MIF and platelet/endothelial cell adhesion molecule 1 (PECAM-1), a measure of vascularization. MIF mRNA was analyzed by quantitative real-time polymerase chain reaction.</p> <p>Results</p> <p>Poorly differentiated carcinoma developed in all BBN treated mice by week 20. MIF WT animals developed T2 disease, while KO animals developed only T1 disease. MIF IHC revealed predominantly urothelial cytoplasmic staining in the WT control animals and a shift toward nuclear staining in WT BBN treated animals. MIF mRNA levels were 3-fold higher in BBN treated animals relative to controls when invasive cancer was present. PECAM-1 staining revealed significantly more stromal vessels in the tumors in WT animals when compared to KOs.</p> <p>Conclusion</p> <p>Muscle invasive bladder cancer with increased stromal vascularity was associated with increased MIF mRNA levels and nuclear redistribution. Consistently lower stage tumors were seen in MIF KO compared to WT mice. These data suggest that MIF may play a role in the progression to invasive bladder cancer.</p
The NâTerminal Tail of hERG Contains an Amphipathic αâHelix That Regulates Channel Deactivation
The cytoplasmic Nâterminal domain of the human etherâaâgoâgo related gene (hERG) K+ channel is critical for the slow deactivation kinetics of the channel. However, the mechanism(s) by which the Nâterminal domain regulates deactivation remains to be determined. Here we show that the solution NMR structure of the Nâterminal 135 residues of hERG contains a previously described PerâArntâSim (PAS) domain (residues 26â135) as well as an amphipathic αâhelix (residues 13â23) and an initial unstructured segment (residues 2â9). Deletion of residues 2â25, only the unstructured segment (residues 2â9) or replacement of the αâhelix with a flexible linker all result in enhanced rates of deactivation. Thus, both the initial flexible segment and the αâhelix are required but neither is sufficient to confer slow deactivation kinetics. Alanine scanning mutagenesis identified R5 and G6 in the initial flexible segment as critical for slow deactivation. Alanine mutants in the helical region had less dramatic phenotypes. We propose that the PAS domain is bound close to the central core of the channel and that the Nâterminal αâhelix ensures that the flexible tail is correctly orientated for interaction with the activation gating machinery to stabilize the open state of the channel
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