216 research outputs found
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Thyroid Function and Dysfunction in Relation to 16 Cardiovascular Diseases.
BACKGROUND: Subclinical thyroid dysfunction, defined as thyroid-stimulating hormone levels outside the reference range with normal free thyroxine levels in asymptomatic patients, is associated with alterations in cardiac hemodynamics. We used Mendelian randomization to assess the role of thyroid dysfunction for cardiovascular disease (CVD). METHODS: Single-nucleotide polymorphisms associated with thyroid function were identified from a genome-wide association meta-analysis in up to 72 167 individuals. Data for genetic associations with CVD were obtained from meta-analyses of genome-wide association studies of atrial fibrillation (n=537 409 individuals), coronary artery disease (n=184 305 individuals), and ischemic stroke (n=438 847) as well as from the UK Biobank (n=367 703 individuals). RESULTS: Genetically predicted thyroid-stimulating hormone levels and hyperthyroidism were statistically significantly associated with atrial fibrillation but no other CVDs at the Bonferroni-corrected level of significance ( P<7.8×10-4). The odds ratios of atrial fibrillation were 1.15 (95% CI, 1.11-1.19; P=2.4×10-14) per genetically predicted 1 SD decrease in thyroid-stimulating hormone levels and 1.05 (95% CI, 1.03-1.08; P=5.4×10-5) for genetic predisposition to hyperthyroidism. Genetically predicted free thyroxin levels were not statistically significantly associated with any CVD. CONCLUSIONS: This Mendelian randomization study supports evidence for a causal association of decreased thyroid-stimulating hormone levels in the direction of a mild form of hyperthyroidism with an increased risk of atrial fibrillation but no other CVDs
Smoking, alcohol consumption, and cancer: A mendelian randomisation study in UK Biobank and international genetic consortia participants.
BACKGROUND: Smoking is a well-established cause of lung cancer and there is strong evidence that smoking also increases the risk of several other cancers. Alcohol consumption has been inconsistently associated with cancer risk in observational studies. This mendelian randomisation (MR) study sought to investigate associations in support of a causal relationship between smoking and alcohol consumption and 19 site-specific cancers. METHODS AND FINDINGS: We used summary-level data for genetic variants associated with smoking initiation (ever smoked regularly) and alcohol consumption, and the corresponding associations with lung, breast, ovarian, and prostate cancer from genome-wide association studies consortia, including participants of European ancestry. We additionally estimated genetic associations with 19 site-specific cancers among 367,643 individuals of European descent in UK Biobank who were 37 to 73 years of age when recruited from 2006 to 2010. Associations were considered statistically significant at a Bonferroni corrected p-value below 0.0013. Genetic predisposition to smoking initiation was associated with statistically significant higher odds of lung cancer in the International Lung Cancer Consortium (odds ratio [OR] 1.80; 95% confidence interval [CI] 1.59-2.03; p = 2.26 × 10-21) and UK Biobank (OR 2.26; 95% CI 1.92-2.65; p = 1.17 × 10-22). Additionally, genetic predisposition to smoking was associated with statistically significant higher odds of cancer of the oesophagus (OR 1.83; 95% CI 1.34-2.49; p = 1.31 × 10-4), cervix (OR 1.55; 95% CI 1.27-1.88; p = 1.24 × 10-5), and bladder (OR 1.40; 95% CI 1.92-2.65; p = 9.40 × 10-5) and with statistically nonsignificant higher odds of head and neck (OR 1.40; 95% CI 1.13-1.74; p = 0.002) and stomach cancer (OR 1.46; 95% CI 1.05-2.03; p = 0.024). In contrast, there was an inverse association between genetic predisposition to smoking and prostate cancer in the Prostate Cancer Association Group to Investigate Cancer Associated Alterations in the Genome consortium (OR 0.90; 95% CI 0.83-0.98; p = 0.011) and in UK Biobank (OR 0.90; 95% CI 0.80-1.02; p = 0.104), but the associations did not reach statistical significance. We found no statistically significant association between genetically predicted alcohol consumption and overall cancer (n = 75,037 cases; OR 0.95; 95% CI 0.84-1.07; p = 0.376). Genetically predicted alcohol consumption was statistically significantly associated with lung cancer in the International Lung Cancer Consortium (OR 1.94; 95% CI 1.41-2.68; p = 4.68 × 10-5) but not in UK Biobank (OR 1.12; 95% CI 0.65-1.93; p = 0.686). There was no statistically significant association between alcohol consumption and any other site-specific cancer. The main limitation of this study is that precision was low in some analyses, particularly for analyses of alcohol consumption and site-specific cancers. CONCLUSIONS: Our findings support the well-established relationship between smoking and lung cancer and suggest that smoking may also be a risk factor for cancer of the head and neck, oesophagus, stomach, cervix, and bladder. We found no evidence supporting a relationship between alcohol consumption and overall or site-specific cancer risk
Registers of the Swedish total population and their use in medical research
The primary aim of the Swedish national population registration system is to
obtain data that (1) reflect the composition, relationship and identities of the
Swedish population and (2) can be used as the basis for correct decisions and
measures by government and other regulatory authorities. For this purpose, Sweden
has established two population registers: (1) The Population Register, maintained
by the Swedish National Tax Agency ("Folkbokforingsregistret"); and (2) The Total
Population Register (TPR) maintained by the government agency Statistics Sweden
("Registret over totalbefolkningen"). The registers contain data on life events
including birth, death, name change, marital status, family relationships and
migration within Sweden as well as to and from other countries. Updates are
transmitted daily from the Tax Agency to the TPR. In this paper we describe the
two population registers and analyse their strengths and weaknesses. Virtually
100 % of births and deaths, 95 % of immigrations and 91 % of emigrations are
reported to the Population Registers within 30 days and with a higher proportion
over time. The over-coverage of the TPR, which is primarily due to underreported
emigration data, has been estimated at up to 0.5 % of the Swedish population.
Through the personal identity number, assigned to all residents staying at least
1 year in Sweden, data from the TPR can be used for medical research purposes,
including family design studies since each individual can be linked to his or her
parents, siblings and offspring. The TPR also allows for identification of
general population controls, participants in cohort studies, as well as
calculation of follow-up time.NonePublishe
Therapeutic Myeloperoxidase Inhibition Attenuates Neutrophil Activation, ANCA-Mediated Endothelial Damage, and Crescentic GN
BACKGROUND: Myeloperoxidase released after neutrophil and monocyte activation can generate reactive oxygen species, leading to host tissue damage. Extracellular glomerular myeloperoxidase deposition, seen in ANCA-associated vasculitis, may enhance crescentic GN through antigen-specific T and B cell activation. Myeloperoxidase-deficient animals have attenuated GN early on, but augmented T cell responses. We investigated the effect of myeloperoxidase inhibition, using the myeloperoxidase inhibitor AZM198, to understand its potential role in treating crescentic GN.
METHODS: We evaluated renal biopsy samples from patients with various forms of crescentic GN for myeloperoxidase and neutrophils, measured serum myeloperoxidase concentration in patients with ANCA-associated vasculitis and controls, and assessed neutrophil extracellular trap formation, reactive oxygen species production, and neutrophil degranulation in ANCA-stimulated neutrophils in the absence and presence of AZM198. We also tested the effect of AZM198 on ANCA-stimulated neutrophil-mediated endothelial cell damage in vitro, as well as on crescentic GN severity and antigen-specific T cell reactivity in the murine model of nephrotoxic nephritis.
RESULTS: All biopsy specimens with crescentic GN had extracellular glomerular myeloperoxidase deposition that correlated significantly with eGFR and crescent formation. In vitro, AZM198 led to a significant reduction in neutrophil extracellular trap formation, reactive oxygen species production, and released human neutrophil peptide levels, and attenuated neutrophil-mediated endothelial cell damage. In vivo, delayed AZM198 treatment significantly reduced proteinuria, glomerular thrombosis, serum creatinine, and glomerular macrophage infiltration, without increasing adaptive T cell responses.
CONCLUSIONS: Myeloperoxidase inhibition reduced neutrophil degranulation and neutrophil-mediated endothelial cell damage in patients with ANCA-associated vasculitis. In preclinical crescentic GN, delayed myeloperoxidase inhibition suppressed kidney damage without augmenting adaptive immune responses, suggesting it might offer a novel adjunctive therapeutic approach in crescentic GN
Circulating Brain-Injury Markers After Surgery for Craniosynostosis
Objective: Historically, there have been few quantitative methods for effectively evaluating outcomes after surgery for craniosynostosis. In this prospective study, we assessed a novel approach for detecting possible postsurgery brain injury in patients with craniosynostosis. Methods: We included consecutive patients operated on for sagittal (pi-plasty or craniotomy combined with springs) or metopic (frontal remodeling) synostosis at the Craniofacial Unit at Sahlgrenska University Hospital, Gothenburg, Sweden, from January 2019 to September 2020. Plasma concentrations of the brain-injury biomarkers neurofilament light (NfL), glial fibrillary acidic protein (GFAP), and tau were measured immediately before induction of anesthesia, immediately before and after surgery, and on the first and the third postoperative days using single-molecule array assays. Results: Of the 74 patients included, 44 underwent craniotomy combined with springs for sagittal synostosis, 10 underwent pi-plasty for sagittal synostosis, and 20 underwent frontal remodeling for metopic synostosis. Compared with baseline, GFAP level showed a maximal significant increase at day 1 after frontal remodeling for metopic synostosis and pi-plasty (P = 0.0004 and P = 0.003, respectively). By contrast, craniotomy combined with springs for sagittal synostosis showed no increase in GFAP. For neurofilament light, we found a maximal significant increase at day 3 after surgery for all procedures, with significantly higher levels observed after frontal remodeling and pi-plasty compared with craniotomy combined with springs (P < 0.001). Conclusions: These represent the first results showing significantly increased plasma levels of brain-injury biomarkers after surgery for craniosynostosis. Furthermore, we found that more extensive cranial vault procedures resulted in higher levels of these biomarkers relative to less extensive procedures
The frequency of CD127low expressing CD4+CD25high T regulatory cells is inversely correlated with human T lymphotrophic virus type-1 (HTLV-1) proviral load in HTLV-1-infection and HTLV-1-associated myelopathy/tropical spastic paraparesis
<p>Abstract</p> <p>Background</p> <p>CD4<sup>+</sup>CD25<sup>high </sup>regulatory T (T<sub>Reg</sub>) cells modulate antigen-specific T cell responses, and can suppress anti-viral immunity. In HTLV-1 infection, a selective decrease in the function of T<sub>Reg </sub>cell mediated HTLV-1-tax inhibition of FOXP3 expression has been described. The purpose of this study was to assess the frequency and phenotype of T<sub>Reg </sub>cells in HTLV-1 asymptomatic carriers and in HTLV-1-associated neurological disease (HAM/TSP) patients, and to correlate with measures of T cell activation.</p> <p>Results</p> <p>We were able to confirm that HTLV-I drives activation, spontaneous IFNγ production, and proliferation of CD4+ T cells. We also observed a significantly lower proportion of CTLA-4<sup>+ </sup>T<sub>Reg </sub>cells (CD4<sup>+</sup>CD25<sup>high </sup>T cells) in subjects with HAM/TSP patients compared to healthy controls. Ki-67 expression was negatively correlated to the frequency of CTLA-4<sup>+ </sup>T<sub>Reg </sub>cells in HAM/TSP only, although Ki-67 expression was inversely correlated with the percentage of CD127<sup>low </sup>T<sub>Reg </sub>cells in healthy control subjects. Finally, the proportion of CD127<sup>low </sup>T<sub>Reg </sub>cells correlated inversely with HTLV-1 proviral load.</p> <p>Conclusion</p> <p>Taken together, the results suggest that T<sub>Reg </sub>cells may be subverted in HAM/TSP patients, which could explain the marked cellular activation, spontaneous cytokine production, and proliferation of CD4<sup>+ </sup>T cells, in particular those expressing the CD25<sup>high</sup>CD127<sup>low </sup>phenotype. T<sub>Reg </sub>cells represent a potential target for therapeutic intervention for patients with HTLV-1-related neurological diseases.</p
Genetically proxied milk consumption and risk of colorectal, bladder, breast, and prostate cancer: a two-sample Mendelian randomization study
Funder: EC-Innovative Medicines Initiative (BigData@Heart)Funder: National Institute for Health Research [Cambridge Biomedical Research Centre at the Cambridge University Hospitals NHS Foundation Trust]Abstract: Background: Observational studies have shown that milk consumption is inversely associated with colorectal, bladder, and breast cancer risk, but positively associated with prostate cancer. However, whether the associations reflect causality remains debatable. We investigated the potential causal associations of milk consumption with the risk of colorectal, bladder, breast, and prostate cancer using a genetic variant near the LCT gene as proxy for milk consumption. Methods: We obtained genetic association estimates for cancer from the UK Biobank (n = 367,643 women and men), FinnGen consortium (n = 135,638 women and men), Breast Cancer Association Consortium (n = 228,951 women), and Prostate Cancer Association Group to Investigate Cancer Associated Alterations in the Genome consortium (n = 140,254 men). Milk consumption was proxied by a genetic variant (rs4988235 or rs182549) upstream of the gene encoding lactase, which catalyzes the breakdown of lactose. Results: Genetically proxied milk consumption was associated with a reduced risk of colorectal cancer. The odds ratio (OR) for each additional milk intake increasing allele was 0.95 (95% confidence interval [CI] 0.91–0.99; P = 0.009). There was no overall association of genetically predicted milk consumption with bladder (OR 0.99; 95% CI 0.94–1.05; P = 0.836), breast (OR 1.01; 95% CI 1.00–1.02; P = 0.113), and prostate cancer (OR 1.01; 95% CI 0.99–1.02; P = 0.389), but a positive association with prostate cancer was observed in the FinnGen consortium (OR 1.07; 95% CI 1.01–1.13; P = 0.026). Conclusions: Our findings strengthen the evidence for a protective role of milk consumption on colorectal cancer risk. There was no or limited evidence that milk consumption affects the risk of bladder, breast, and prostate cancer
The effect of past use of oral contraceptive on bone mineral density, bone biochemical markers and muscle strength in healthy pre and post menopausal women
<p>Abstract</p> <p>Background</p> <p>during adulthood, most studies have reported that oral contraceptive (OC) pills had neutral, or possibly beneficial effect on bone health. We proposed this study of pre and post menopausal women assessing BMD, bone biochemical markers and physical performance among OC past users and comparable women who have never use Ocs.</p> <p>Methods</p> <p>A cross-sectional study comparing the bone density, bone biochemical markers (osteocalcin, CTX) and three measures to assess physical performance: timed get-up-and-go test "TGUG", five-times-sit-to-stand test "5 TSTS" and 8-feet speed walk "8 FSW" of users and never users OC. We were recruited 210 women who used OC for at least 2 years with that of 200 nonusers was carried out in pre and postmenopausal women (24-86 years).</p> <p>Results</p> <p>when analysing the whole population, BMD and biochemical markers values were similar for Ocs past users and control subjects. However when analysing the subgroup of premenopausal women, there was a statistically significant difference between users and never-users in osteocalcin (15,5 ± 7 ng/ml vs 21,6 ± 9 ng/ml; p = 0,003) and CTX (0,30 ± 0,1 ng/ml vs 0,41 ± 0,2 ng/ml; p = 0,025). This difference persisted after adjustment for age, BMI, age at menarche and number of pregnancies. In contrast, in post menopausal women, there was no difference in bone biochemical markers between OC users and the control. On the other hand OC past users had a significant greater performance than did the never users group. And when analysing the physical performance tests by quartile OC duration we found a significant negative association between the three tests and the use of OC more than 10 years.</p> <p>Conclusion</p> <p>the funding show no evidence of a significant difference in BMD between Ocs users and never user control groups, a decrease in bone turn over in OC pre menopausal users and a greater physical performances in patients who used OC up than 10 years.</p
A high activity index of stearoyl-CoA desaturase is associated with increased risk of fracture in men
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