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80 result(s) for "Sapkota, Yadav"
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The burden of cardiovascular disease and risk for subsequent major adverse cardiovascular events in survivors of childhood cancer: a prospective, longitudinal analysis from the St Jude Lifetime Cohort Study
The effect of the increasing lifetime burden of non-major cardiovascular conditions on risk for a subsequent major adverse cardiovascular event among survivors of childhood cancer has not been assessed. We aimed to characterise the prevalence of major adverse cardiovascular events and their association with the cumulative burden of non-major adverse cardiovascular events in childhood cancer survivors. This is a longitudinal cohort study with participant data obtained from an ongoing cohort study at St Jude Children's Research Hospital: the St Jude Lifetime Cohort Study (SJLIFE). Prospective clinical follow-up was of 5-year survivors of childhood cancer who were diagnosed when aged younger than 25 years from 1962 to 2012. Age-frequency, sex-frequency, and race-frequency matched community-control participants completed a similar one-time clinical assessment. 22 cardiovascular events were graded using a St Jude Children's Research Hospital-modified version of the National Cancer Institute Common Terminology Criteria for Adverse Events (version 4.03). Cumulative incidence and burden of the primary outcome of major adverse cardiovascular events (cardiomyopathy, myocardial infarction, stroke, and other cardiovascular-related mortality) were estimated. Rate ratios (RR) of the association of major adverse cardiovascular events with 22 non-major adverse cardiovascular events were estimated using multivariable piecewise-exponential regression adjusting for attained age, age at diagnosis, sex, race and ethnicity, treatment era, diagnosis of diabetes, and exposure to cardiotoxic cancer therapies. The St Jude Lifetime Cohort study is registered with ClinicalTrials.gov, NCT00760656, and is ongoing. 9602 5-year survivors of childhood cancer, and 737 community controls were included in the longitudinal follow-up (from Sept 13, 2007, to Dec 17, 2021). The median follow-up was 20·3 years (IQR 12·0–31·4) from the date of primary cancer diagnosis (4311 [44.9%] were females). By the age of 50 years (analysis stopped at age 50 years due to the low number of participants older than that age), the cumulative incidence of major adverse cardiovascular events among survivors was 17·7% (95% CI 15·9–19·5) compared with 0·9% (0·0–2·1) in the community controls. The cumulative burden of major adverse cardiovascular events in survivors was 0·26 (95% CI 0·23–0·29) events per survivor compared with 0·009 (0·000–0·021) events per community control participant. Increasing cumulative burden of grade 1–4 non-major adverse cardiovascular events was associated with an increased future risk of major adverse cardiovascular events (one condition: RR 4·3, 95% CI 3·1–6·0; p<0·0001; two conditions: 6·6, 4·6–9·5; p<0·0001; and three conditions: 7·7, 5·1–11·4; p<0·0001). Increased risk for major adverse cardiovascular events was observed with specific subclinical conditions (eg, grade 1 arrhythmias [RR 1·5, 95% CI 1·2–2·0; p=0·0017]), grade 2 left ventricular systolic dysfunction (2·2, 1·6–3·1; p<0·0001), grade 2 valvular disorders (2·2, 1·2–4·0; p=0·013), but not grade 1 hypercholesterolaemia, grade 1–2 hypertriglyceridaemia, or grade 1–2 vascular stenosis. Among an ageing cohort of survivors of childhood cancer, the accumulation of non-major adverse cardiovascular events, including subclinical conditions, increased the risk of major adverse cardiovascular events and should be the focus of interventions for early detection and prevention of major adverse cardiovascular events. The US National Cancer Institute and the American Lebanese Syrian Associated Charities.
Development and validation of age-specific risk prediction models for primary ovarian insufficiency in long-term survivors of childhood cancer: a report from the Childhood Cancer Survivor Study and St Jude Lifetime Cohort
Female survivors of childhood cancer are at risk for primary ovarian insufficiency (POI), defined as the cessation of gonadal function before the age of 40 years. We aimed to develop and validate models to predict age-specific POI risk among long-term survivors of childhood cancer. To develop models to predict age-specific POI risk for the ages of 21–40 years, we used data from the Childhood Cancer Survivor Study (CCSS). Female survivors aged 18 years or older at their latest follow-up, with self-reported menstrual history information and free of subsequent malignant neoplasms within 5 years of diagnosis, were included. We evaluated models that used algorithms based on statistical or machine learning to consider all predictors, including cancer treatments. Cross-validated prediction performance metrics (eg, area under the receiver operating characteristic curve [AUROC]) were compared to select the best-performing models. For external validation of the models, we used data from 5-year survivors in the St Jude Lifetime Cohort (SJLIFE) with ovarian status clinically ascertained using hormone measurements (menopause defined by follicle stimulating hormone >30 mIU/mL and oestradiol <17 pg/mL) and medical chart or questionnaire review. We also evaluated an SJLIFE-based polygenic risk score for POI among 1985 CCSS survivors with genotype data available. 7891 female CCSS survivors (922 with POI) were included in the development of the POI risk prediction model, and 1349 female SJLIFE survivors (101 with POI) were included in the validation study. Median follow-up from cancer diagnosis was 23·7 years (IQR 18·3–30·0) in CCSS and 15·1 years (10·4–22·9) in SJLIFE. Between the ages of 21 and 40 years, POI prevalence increased from 7·9% (95% CI 7·3–8·5) to 18·6% (17·3–20·0) in CCSS and 7·3% (5·8–8·9) to 14·9% (11·6–19·1) in SJLIFE. Age-specific logistic regression models considering ovarian radiation dosimetry or prescribed pelvic and abdominal radiation dose, along with individual chemotherapy predictors, performed well in CCSS. In the SJLIFE validation, the prescribed radiation dose model performed well (AUROC 0·88–0·95), as did a simpler model that considered any exposures to pelvic or abdominal radiotherapy or alkylators (0·82–0·90). Addition of the polygenic risk predictor significantly improved the average positive predictive value (from 0·76 [95% CI 0·63–0·89] to 0·87 [0·80–0·94]; p=0·029) among CCSS survivors treated with ovarian radiation and chemotherapy. POI risk prediction models using treatment information showed robust prediction performance in adult survivors of childhood cancer. Canadian Institutes of Health Research, US National Cancer Institute.
Genetic variation in POT1 and risk of thyroid subsequent malignant neoplasm: A report from the Childhood Cancer Survivor Study
Telomere length is associated with risk for thyroid subsequent malignant neoplasm in survivors of childhood cancer. Here, we investigated associations between thyroid subsequent malignant neoplasm and inherited variation in telomere maintenance genes. We used RegulomeDB to annotate the functional impact of variants mapping to 14 telomere maintenance genes among 5,066 five-or-more year survivors who participate in the Childhood Cancer Survivor Study (CCSS) and who are longitudinally followed for incidence of subsequent cancers. Hazard ratios for thyroid subsequent malignant neoplasm were calculated for 60 putatively functional variants with minor allele frequency ≥1% in or near telomere maintenance genes. Functional impact was further assessed by measuring telomere length in leukocyte subsets. The minor allele at Protection of Telomeres-1 (POT1) rs58722976 was associated with increased risk for thyroid subsequent malignant neoplasm (adjusted HR = 6.1, 95% CI: 2.4, 15.5, P = 0.0001; Fisher's exact P = 0.001). This imputed SNP was present in three out of 110 survivors who developed thyroid cancer vs. 14 out of 4,956 survivors who did not develop thyroid cancer. In a subset of 83 survivors with leukocyte telomere length data available, this variant was associated with longer telomeres in B lymphocytes (P = 0.004). Using a functional variant approach, we identified and confirmed an association between a low frequency intronic regulatory POT1 variant and thyroid subsequent malignant neoplasm in survivors of childhood cancer. These results suggest that intronic variation in POT1 may affect key protein binding interactions that impact telomere maintenance and genomic integrity.
Molecular Support for Heterogonesis Resulting in Sesquizygotic Twinning
Evaluation of monochorionic twins and their parents showed that each twin had inherited the same set of maternal alleles (i.e., both twins were derived from the same ovum) and that each twin had inherited, in chimeric fashion, two different sets of paternal alleles (i.e., the genetic lineages of two different spermatozoa were present in each twin).
Contributions of cancer treatment and genetic predisposition to risk of subsequent neoplasms in long-term survivors of childhood cancer: a report from the St Jude Lifetime Cohort and the Childhood Cancer Survivor Study
Survivors of childhood cancer are at risk of subsequent neoplasms (SNs) associated with exposure to radiotherapy and chemotherapy, as well as with genetic predisposition. We aimed to estimate the relative contributions of these risk factors to the total SN burden in survivor populations. We analysed data from two retrospectively constructed cohorts with ongoing recruitment and prospective follow-up: the St Jude Lifetime Cohort (SJLIFE; 4401 participants; NCT00760656) and the Childhood Cancer Survivor Study (CCSS; 7943 participants; NCT01120353). We used multivariable piecewise-exponential models to calculate attributable fractions to assess the contributions of radiotherapy and chemotherapy exposures, genetic predisposition (comparing the top two tertiles with the lowest tertile of polygenic risk scores [PRSs] where the tertile is from external general population corresponding to SN outcome) and lifestyle factors (physical activity, smoking, alcohol consumption, obesity, and diet) to incident of the first occurrences of SNs as the primary outcome. The study was conducted between Jan 1, 2024, and Sept 30, 2024. Of the 12 344 survivors eligible for analysis, median attained age was 33·0 years (IQR 24·1–42·1) in SJLIFE and 36·0 years (29·5–43·6) in CCSS; 6127 (49·6%) were men and 6217 (50·4%) were women. Most patients were White (10 907 [88·4%]). The median follow-up from primary cancer diagnosis was 24·2 years (IQR 11·7–35·4) in SJLIFE (from Sept 13, 2007 to April 20, 2020) and 28·0 years (8·9–37·2) in CCSS (from Jan 1, 1975 to Dec 31, 2023). Cancer treatments and genetic risk jointly contributed to a substantial proportion of incident SN cases with attributable fractions ranging from 30% (95% CI 6–49; sarcoma) to 92% (89–94; meningioma). Higher exposure levels of radiotherapy contributed most, particularly in older (≥35 years; SJLIFE proportion of SNs 44·7% [95% CI 41·9–47·5]) compared with younger (<35 years; 40·0% [37·1–43·3]) follow-up age periods. Elevated genetic risk based on the PRSs accounted for a notable proportion, ranging from 1% (95% CI 0–7; meningioma) to 52% (39–62; thyroid cancer), surpassing contributions of chemotherapies, ranging from 3% (1–6; SMNs) to 35% (19–49; sarcoma). Lifestyle factors contributed negligibly. Cancer treatments and genetic predisposition are primary contributors to the risk of SNs in childhood cancer survivors, and lifestyle factors seem to have a minimal effect. These results highlight the crucial need to consider both treatment history and genetic factors in developing effective risk assessment and surveillance strategies for this vulnerable population. US National Institutes of Health and the American Lebanese Syrian Associated Charities.
Nilotinib-induced alterations in endothelial cell function recapitulate clinical vascular phenotypes independent of ABL1
Nilotinib is a highly effective treatment for chronic myeloid leukemia but has been consistently associated with the development of nilotinib-induced arterial disease (NAD) in a subset of patients. To date, which cell types mediate this effect and whether NAD results from on-target mechanisms is unknown. We utilized human induced pluripotent stem cells (hiPSCs) to generate endothelial cells and vascular smooth muscle cells for in vitro study of NAD. We found that nilotinib adversely affects endothelial proliferation and migration, in addition to increasing intracellular nitric oxide. Nilotinib did not alter endothelial barrier function or lipid uptake. No effect of nilotinib was observed in vascular smooth muscle cells, suggesting that NAD is primarily mediated through endothelial cells. To evaluate whether NAD results from enhanced inhibition of ABL1, we generated multiple ABL1 knockout lines. The effects of nilotinib remained unchanged in the absence of ABL1, suggesting that NAD results from off- rather than on-target signaling. The model established in the present study can be applied to future mechanistic and patient-specific pharmacogenomic studies.
Shared Molecular Genetic Mechanisms Underlie Endometriosis and Migraine Comorbidity
Observational epidemiological studies indicate that endometriosis and migraine co-occur within individuals more than expected by chance. However, the aetiology and biological mechanisms underlying their comorbidity remain unknown. Here we examined the relationship between endometriosis and migraine using genome-wide association study (GWAS) data. Single nucleotide polymorphism (SNP) effect concordance analysis found a significant concordance of SNP risk effects across endometriosis and migraine GWAS. Linkage disequilibrium score regression analysis found a positive and highly significant genetic correlation (rG = 0.38, P = 2.30 × 10−25) between endometriosis and migraine. A meta-analysis of endometriosis and migraine GWAS data did not reveal novel genome-wide significant SNPs, and Mendelian randomisation analysis found no evidence for a causal relationship between the two traits. However, gene-based analyses identified two novel loci for migraine. Also, we found significant enrichment of genes nominally associated (Pgene < 0.05) with both traits (Pbinomial-test = 9.83 × 10−6). Combining gene-based p-values across endometriosis and migraine, three genes, two (TRIM32 and SLC35G6) of which are at novel loci, were genome-wide significant. Genes having Pgene < 0.1 for both endometriosis and migraine (Pbinomial-test = 1.85 ×10−°3) were significantly enriched for biological pathways, including interleukin-1 receptor binding, focal adhesion-PI3K-Akt-mTOR-signaling, MAPK and TNF-α signalling. Our findings further confirm the comorbidity of endometriosis and migraine and indicate a non-causal relationship between the two traits, with shared genetically-controlled biological mechanisms underlying the co-occurrence of the two disorders.
Portable X-Ray Fluorescence Spectroscopy for Rapid and Cost-Effective Determination of Elemental Composition of Ground Forage
The recent development of portable X-ray fluorescence spectrometers (PXRF) has created new avenues for rapid plant elemental concentration determination at reduced cost while avoiding hazardous chemicals. A few studies have indicated the potential use of PXRF for homogenous plant tissue analysis. However, there is a lack of information for analysis of heterogeneous plant samples like livestock forage, which consists of a mixture of several species and plant parts, each varying in elemental concentration. Our objective was to evaluate PXRF for forage analysis, specifically the effect of forage particle size and scan time on important elements including P, K, Ca, and Fe determination. Hay samples ( = 42) were oven dried (60°C for 3 days) and ground into three particle sizes (≤0.5 mm, 0.25-0.5 mm and 1-2 mm). Prepared samples were scanned by PXRF using a vacuum (<10 torr) without a filter. Samples were placed in cups over thin prolene X-ray film and scanned for 180 s. A subset ( = 29) were also scanned for 60 and 120 s. PXRF counts for P, K, Ca, and Fe were compared with laboratory Inductively Coupled Plasma Optical Emission Spectroscopy (ICP) determinations, using regression models. Results indicated that these elements could potentially be determined with PXRF ( ≥ 0.70) in heterogeneous forage samples. Relationship strength increased with decreasing particle size, however, the relationship was still strong ( ≥ 0.57) at the largest particle size. Scanning time did not affect the relationship with ICP concentration for any of the particle sizes evaluated. This work demonstrated that with the right sample preparation PXRF can obtain results comparable to acid digestion and ICP regardless of sample composition, and suggests the potential for determinations.
Genome-wide haplotype association analysis of primary biliary cholangitis risk in Japanese
Primary biliary cholangitis (PBC) susceptibility loci have largely been discovered through single SNP association testing. In this study, we report genic haplotype patterns associated with PBC risk genome-wide in two Japanese cohorts. Among the 74 genic PBC risk haplotype candidates we detected with a novel methodological approach in a discovery cohort of 1,937 Japanese, nearly two-thirds were replicated (49 haplotypes, Bonferroni-corrected P < 6.8 × 10 −4 ) in an independent Japanese cohort (N = 949). Along with corroborating known PBC-associated loci ( TNFSF15 , HLA-DRA ), risk haplotypes may potentially model cis -interactions that regulate gene expression. For example, one replicated haplotype association (9q32–9q33.1, OR = 1.7, P = 3.0 × 10 −21 ) consists of intergenic SNPs outside of the human leukocyte antigen (HLA) region that overlap regulatory histone mark peaks in liver and blood cells, and are significantly associated with TNFSF8 expression in whole blood. We also replicated a novel haplotype association involving non-HLA SNPs mapped to UMAD1 (7p21.3; OR = 15.2, P = 3.9 × 10 −9 ) that overlap enhancer peaks in liver and memory T h cells. Our analysis demonstrates the utility of haplotype association analyses in discovering and characterizing PBC susceptibility loci.