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BACKGROUND: During gamete development and spermatogenesis, certain genes on the Y chromosome (Yq) in the Male-Specific Region (MSR) are responsible for human gametes formation. The long arm Yq is composed of both euchromatin and the genetically inactive heterochromatin regions. This region contains the Azoospermia factors AZFa, AZFb and AZFc. In the case of male infertility, microdeletions on the Yq chromosome appear to be structural chromosomal anomalies linked to sperm abnormality. METHODS: The present study aimed to look at the incidence, of Asthenospermia (AS), Teratospermia (TS), Oligospermia (OS) and Oligoasthenoteratospermia (OAT) patterns of Y chromosomal microdeletions in Indian infertile men with an (AZF a, b, c). This study was conducted with 75 infertile men as cases and 75 fertile men as a control for AZF locus microdeletion utilizing sequence-tagged sites. RESULTS: The AZFc region of germ cell DNA (50.6%) was the most deleted section in infertile men when compared to blood DNA (21.3%), followed by deletions in the AZFb region (21.3%) in germ cell DNA whereas blood DNA had no microdeletion in the AZFa region in both germ cell DNA and blood DNA. Infertile men displayed significant Yq microdeletion in both AZFb and also AZFc. Around 33% (25) of 75 infertile men had AZF (a, b, c) region microdeletion in blood DNA, compared to it germ cell DNA had a larger percentage of 72% (54) of Y chromosome microdeletions in the study samples. CONCLUSION: A high-frequency rate of microdeletions seen in germ cell DNA. PCR-based Y chromosome microdeletion screening using germ cell DNA along with Genomic DNA might help in screening for genetic abnormality in infertile men who endure assisted reproductive technology treatments. This study might be attributable to the interplay of lifestyle and genetic factors, both contributing to the risk of developing these germ-line deletions.
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Azoospermia , Infertilidade Masculina , Oligospermia , Masculino , Humanos , Incidência , Sêmen , Infertilidade Masculina/epidemiologia , Infertilidade Masculina/genética , Infertilidade Masculina/diagnóstico , Oligospermia/epidemiologia , Oligospermia/genética , Oligospermia/diagnóstico , Deleção Cromossômica , Espermatozoides , Cromossomos Humanos Y/genética , DNA , Azoospermia/genéticaRESUMO
Radiological accidents and nuclear terrorism pose an increased threat to members of the public who, following such an event, would need to be assessed for medical care by fast triage. Assay methods such as chromosome aberrations (CA), cytokinesis-block micronucleus (CBMN) and fluorescence in situ hybridization (FISH) techniques have been well established for dose estimation and their potential for handling more samples has also been proved with automation. However, culturing of lymphocytes is an inevitable step, which limits the potential of these markers for triage. In vitro analysis of gamma-H2AX (γ-H2AX), gene and microRNA (miRNA) markers do not require culturing of lymphocytes, and as such have been suggested as attractive tools for triage. Despite studies reporting in vitro dose-response curves, limited evidence is available evaluating the suitability of these assays in real situations. In this study, we have measured the absorbed dose using γ-H2AX, gene (GADD45A, FDXR, and CDKN1A) and miRNA-101 expression in blood samples of cancer patients (n = 20) who had undergone partial-body radiotherapy and compared with the derived equivalent whole-body doses (EWBD). The obtained results from all patients showed a significant (p < 0.05) increase of γ-H2AX foci in post-irradiated as compared to pre-irradiated samples. Moreover, estimated doses using γ-H2AX foci showed a correlation with the derived EWBD (r2 = 0.60, p = 0.0003) and was also shown to be dependent on the irradiated body volume. Consistent with γ-H2AX foci frequency, an increase in fold change expression of genes and miRNA-101 was observed. However, the estimated dose significantly varied among the subjects and showed poor correlation (r2 = 0.09, 0.04, 0.01 and 0.03 for GADD45A, FDXR, CDKN1A and miRNA-101, respectively) with EWBD. The overall results suggest that the established in vitro γ-H2AX assay is suitable for the detection of radiation exposure and can also provide an estimate of the dose in in vivo irradiated samples. The genes and miRNA-101 markers showed increased expression; nevertheless, there is a need for further improvements to measure doses accurately using these markers.
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Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Histonas/sangue , MicroRNAs/genética , Neoplasias/radioterapia , Doses de Radiação , Proteínas de Ciclo Celular/genética , Inibidor de Quinase Dependente de Ciclina p21/genética , Relação Dose-Resposta à Radiação , Feminino , Humanos , Linfócitos/metabolismo , Linfócitos/efeitos da radiação , Masculino , Pessoa de Meia-Idade , Neoplasias/sangue , Neoplasias/genéticaRESUMO
BACKGROUND & OBJECTIVES: Subtelomeres are prone to deleterious rearrangements owing to their proximity to unique sequences on the one end and telomeric repetitive sequences, which increase their tendency to recombine, on the other end. These subtelomeric rearrangements resulting in segmental aneusomy are reported to contribute to the aetiology of idiopathic intellectual disability/developmental delay (ID/DD). We undertook this study to estimate the frequency of subtelomeric rearrangements in children with ID/DD. METHODS: One hundred and twenty seven children with idiopathic ID/DD were tested for subtelomeric rearrangements using karyotyping and FISH. Blood samples were cultured, harvested, fixed and GTG-banded using the standard protocols. RESULTS: Rearrangements involving the subtelomeres were observed in 7.8 per cent of the tested samples. Detection of rearrangements visible at the resolution of the karyotype constituted 2.3 per cent, while those rearrangements detected only with FISH constituted 5.5 per cent. Five deletions and five unbalanced translocations were detected. Analysis of parental samples wherever possible was informative regarding the inheritance of the rearrangement. INTERPRETATION & CONCLUSIONS: The frequency of subtelomeric rearrangements observed in this study was within the reported range of 0-35 per cent. All abnormal genotypes were clinically correlated. Further analysis with array technologies presents a future prospect. Our results suggest the need to test individuals with ID/DD for subtelomeric rearrangements using sensitive methods such as FISH.
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Deficiências do Desenvolvimento/genética , Rearranjo Gênico/genética , Deficiência Intelectual/genética , Telômero/genética , Adolescente , Criança , Pré-Escolar , Aberrações Cromossômicas , Deficiências do Desenvolvimento/patologia , Feminino , Humanos , Hibridização in Situ Fluorescente/métodos , Lactente , Deficiência Intelectual/patologia , Cariótipo , MasculinoRESUMO
Measurement of γ-H2AX protein changes in the peripheral blood lymphocytes (PBL) of individuals exposed to ionizing radiation is a simple, sensitive, and rapid assay for radiation triage and early marker of dose estimation. The qualitative and quantitative measurements of the protein changes were examined using flow cytometry and microscopy. Whole blood and isolated lymphocytes were exposed in vitro between 0.1 and 5 Gy doses of (60) Co γ-radiation at a dose rate of 1 Gy/min. Radiation induced γ-H2AX foci frequency (n = 3) and relative fluorescence intensity (n = 7) in PBL was measured at 0.5 and 2 hrs postexposure. The observed dose response for γ-H2AX foci frequency at both time points, for whole blood and isolated lymphocytes did not show any significant (P > 0.05) differences. However, when compared with γ-H2AX foci frequency scored manually (microscopy), the semiautomated analysis (captured images) showed a better correlation (r(2) = 0.918) than that obtained with automated (Metafer) scoring (r(2) = 0.690). It is noteworthy to mention that, the γ-H2AX foci frequency quantified using microscopy showed a dose dependent increase up to 2 Gy and the relative fluorescence intensity (RFI) measured with flow cytometry revealed an increase up to 5 Gy in the PBL exposed in vitro. Moreover, a better correlation was observed between the γ-H2AX foci frequency obtained by manual scoring and RFI (r(2) = 0.910). Kinetic studies showed that the γ-H2AX foci remain more or less unchanged up to 4 hrs and reduces gradually over 48 hrs of postexposure at 37°C. Further, inter and intra-laboratory comparisons showed consistency in the scoring of γ-H2AX foci frequency by manual and semiautomated scoring. The overall results suggest that measurement of γ-H2AX (microscopy and flow cytometry) should be employed within 4 to 6 hrs for a reliable dosimetry either by sharing the work load between the laboratories or investing more manpower; however, triage can be possible even up to 48 hrs of postirradiation.
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Raios gama , Histonas/metabolismo , Linfócitos/metabolismo , Linfócitos/efeitos da radiação , Adulto , Automação , Separação Celular , Radioisótopos de Cobalto , Feminino , Citometria de Fluxo , Fluorescência , Humanos , Cinética , MasculinoRESUMO
From attributing mutations to cancers with the advent of cutting-edge genetic technology in recent decades, to re-searching the age-old theory of intrinsic metabolic shift of cancers (Warburg's glycolysis), the quest for a precise panacea for mainly the metastatic cancers, remains incessant. This review delineates the advanced glycation end product (AGE)-receptor for AGE (RAGE) pathway driven intricate oncogenic cues, budding from the metabolic (glycolytic) reliance of tumour cells, branching into metastatic emergence of malignancies. Strong AGE-RAGE concomitance in metastasis, chemo-resistance and cancer resurgence adversely incite disease progression and patient mortality. At the conjunction of metabolic and metastatic shift of cancers, are the "glycolytically" generated AGEs and AGE-activated RAGE, instigating aberrant molecular pathways, culminating in aggressive malignancies. AGEs as by-products of metabolic insurgence, modify the metabolome, epigenome and microbiome, besides coercing the inter-, intra- and extra-cellular micro-milieu conducive for oncogenic events like epithelial-mesenchymal transition (EMT). AGE-RAGE synergistically elicit ATP surge for surplus energy, autophagy for apoptotic evasion and chemo-resistance, insulin-like growth factor 1 (IGF-1) for meta-inflammation and angiogenesis, high mobility group box-1 (HMGB1) for immune tolerance, S100 proteins for metastasis, and p53 protein attenuation for tumour suppression. AGEs are pronouncedly reported in invasive forms of breast, prostate, colon and pancreatic cancers, higher in patients with cancer than healthy counterparts, and higher in advanced stage than localized phase. Hence, the investigation of person-specific presence of AGEs, soluble RAGE and AGE-activated RAGE can be advocated as impending bio-markers for diagnostic, prognostic and therapeutic purposes, to predict cancer risk in patients with diabetes, obesity, metabolic syndrome as well as general population, to monitor prognosis and metastasis in patients with cancer, and to reckon complications in cancer survivors. Furthermore, clinical reports of exogenous (dietary) and endogenous (internally formed) AGEs in cancer patients, and contemporary clinical trials involving AGE-RAGE axis in cancer are underlined with theranostic implications.
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PURPOSE: The actual global burden of Latent Autoimmune Diabetes of Adults (LADA) remains unknown even though its prevalence is almost equal to the type 1 form of diabetes. Hence the present systematic review and meta-analysis were performed to estimate the prevalence of LADA among diabetic individuals using the studies published at global levels. METHODS: A comprehensive literature revival was performed to identify articles on the prevalence of LADA published till 2023. The prevalence estimates were calculated using DerSimonian and Laird random-effects models with a heterogeneity measure by Cochrane Q and I2 statistics. Publication bias was assessed by the Doi plot and Luis Furuya-Kanamori asymmetry index (LFKindex). P < 0.05 was considered statistically significant. RESULTS: The overall pooled prevalence of LADA obtained from a total of 51,725 diabetic individuals was found to be 8.9% (95%CI 7.5-10.4, P < 0.001) with a prevalence range of 2.3% in to 18.9% in United Arab Emirates and Bahrain respectively. Subgroup analysis of LADA in the context of the IDF geographic regions showed a higher prevalence in North America (13.5%), 9.5% in Middle East and North Africa, 9.4% in Africa, 9.2% in South East Asia, 8.3% in Western Pacific and the lowest prevalence of 7.0% in Europe. CONCLUSION: The Meta-analysis revealed a worldwide prevalence of LADA as 8.9%, with the highest prevalence in Bahrain and the lowest in United Arab Emirates. Further, the higher prevalence in some IDF regions and the inconsistent association between socioeconomic status and LADA recommend more research in the future.
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Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Intolerância à Glucose , Diabetes Autoimune Latente em Adultos , Adulto , Humanos , Diabetes Mellitus Tipo 2/epidemiologia , Prevalência , Diabetes Autoimune Latente em Adultos/epidemiologia , Diabetes Mellitus Tipo 1/epidemiologia , Europa (Continente)RESUMO
In the modern developing society, application of radiation has increased extensively. With significant improvement in the radiation protection practices, exposure to human could be minimized substantially, but cannot be avoided completely. Assessment of exposure is essential for regulatory decision and medical management as applicable. Until now, cytogenetic changes have served as surrogate marker of radiation exposure and have been extensively employed for biological dose estimation of various planned and unplanned exposures. Dicentric Chromosomal Aberration (DCA) is radiation specific and is considered as gold standard, micronucleus is not very specific to radiation and is considered as an alternative method for biodosimetry. In this study dose response curves were generated for X-ray induced "dicentric + ring" and micronuclei, in lymphocytes of three healthy volunteers [2 females (age 22, 23 years) and 1 male (24 year)]. The blood samples were irradiated with X-ray using LINAC (energy 6 MV, dose rate 6 Gy/min), in the dose range of 0-5Gy. Irradiated blood samples were cultured and processed to harvest metaphases, as per standard procedures recommended by International Atomic Energy Agency. Pooled data obtained from all the three volunteers, were in agreement with Poisson distribution for "dicentric + ring", however over dispersion was observed for micronuclei. Data ("dicentric + ring" and micronuclei) were fitted by linear quadratic model of the expression Y[bond, double bond]C + αD + ßD2 using Dose Estimate software, version 5.2. The data fit has resulted in linear coefficient α = 0.0006 (±0.0068) "dicentric + ring" cell-1 Gy-1 and quadratic coefficient ß = 0.0619 (±0.0043) "dicentric + ring" cell-1 Gy-2 for "dicentric + ring" and linear coefficient α = 0.0459 ± (0.0038) micronuclei cell-1 Gy-1 and quadratic coefficient ß = 0.0185 ± (0.0010) micronuclei cell-1 Gy-2 for micronuclei, respectively. Background frequencies for "dicentric + ring" and micronuclei were 0.0006 ± 0.0004 and 0.0077 ± 0.0012 cell-1, respectively. Established curves were validated, by reconstructing the doses of 8 dose blinded samples (4 by DCA and 4 by CBMN) using coefficients generated here. Estimated doses were within the variation of 0.9-16% for "dicentric + ring" and 21.7-31.2% for micronuclei respectively. These established curves have potential to be employed for biodosimetry of occupational, clinical and accidental exposures, for initial triage and medical management.
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PURPOSE: Pediatric acute lymphoblastic leukemia (pALL) patients have better overall survival and methotrexate (MTX) is an effective drug used in their treatment. However, the treatment-related adverse effects (TRAEs) have a bigger impact on the therapy. In this study, we have evaluated the association of polymorphisms in genes encoding proteins engaged in MTX metabolism, and the cytogenetic aberrations with TRAEs. METHODS: A total of 115 patients between the age of 1 and 18 years (average: 6.6) under maintenance therapy were selected for the study. SLC19A1 (c.80G > A), MTHFR (c.677C > T; c.1298A > C), and TYMS (c.*450_*455del) genotypes were determined using PCR techniques and Sanger sequencing. Cytogenetic and SNP findings were analyzed for any association with the reported toxicities using odds ratio, chi-square test, multifactor dimensionality reduction (MDR) analysis for synergistic effect and, multinomial logistic regression analysis for the likelihood of adverse events. RESULTS: Among the evaluated genetic variations, SLC19A1 (c.80G > A) was significantly associated with TRAEs (OR = 5.71, p = 0.002). Multinomial logistic regression analysis (chi-sq = 16.64, p < 0.001) and MDR analysis (chi-sq = 10.51 p < 0.001) confirmed the finding. On the other hand, no significant association was observed between adverse events and any specific cytogenetic aberration. CONCLUSION: SLC19A1 facilitates the import of cyclic dinucleotides and reduced folates, evaluating genotypes in this gene can help in better management of patients on methotrexate treatment. Assessing a broader gene panel can help in finding more associated markers and delivering personalized medicine to the patients.
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Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Leucemia-Linfoma Linfoblástico de Células Precursoras , Adolescente , Criança , Pré-Escolar , Análise Citogenética , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/tratamento farmacológico , Genótipo , Humanos , Lactente , Metotrexato/efeitos adversos , Polimorfismo Genético , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismoRESUMO
To assess the burden of type 2 diabetes (T2D) and its genetic profile in endogamous populations of India given the paucity of data, we aimed to determine the prevalence of T2D and estimate its heritability using family-based cohorts from three distinct Endogamous Ethnic Groups (EEGs) representing Northern (Rajasthan [Agarwals: AG]) and Southern (Tamil Nadu [Chettiars: CH] and Andhra Pradesh [Reddys: RE]) states of India. For comparison, family-based data collected previously from another North Indian Punjabi Sikh (SI) EEG was used. In addition, we examined various T2D-related cardiometabolic traits and determined their heritabilities. These studies were conducted as part of the Indian Diabetes Genetic Studies in collaboration with US (INDIGENIUS) Consortium. The pedigree, demographic, phenotypic, covariate data and samples were collected from the CH, AG, and RE EEGs. The status of T2D was defined by ADA guidelines (fasting glucose ≥ 126 mg/dl or HbA1c ≥ 6.5% and/or use of diabetes medication/history). The prevalence of T2D in CH (N = 517, families = 21, mean age = 47y, mean BMI = 27), AG (N = 530, Families = 25, mean age = 43y, mean BMI = 27), and RE (N = 500, Families = 22, mean age = 46y, mean BMI = 27) was found to be 33%, 37%, and 36%, respectively, Also, the study participants from these EEGs were found to be at increased cardiometabolic risk (e.g., obesity and prediabetes). Similar characteristics for the SI EEG (N = 1,260, Families = 324, Age = 51y, BMI = 27, T2D = 75%) were obtained previously. We used the variance components approach to carry out genetic analyses after adjusting for covariate effects. The heritability (h2) estimates of T2D in the CH, RE, SI, and AG were found to be 30%, 46%, 54%, and 82% respectively, and statistically significant (P ≤ 0.05). Other T2D related traits (e.g., BMI, lipids, blood pressure) in AG, CH, and RE EEGs exhibited strong additive genetic influences (h2 range: 17% [triglycerides/AG and hs-CRP/RE] - 86% [glucose/non-T2D/AG]). Our findings highlight the high burden of T2D in Indian EEGs with significant and differential additive genetic influences on T2D and related traits.
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Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Adulto , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/genética , Etnicidade/genética , Glucose , Humanos , Índia/epidemiologia , Pessoa de Meia-IdadeRESUMO
OBJECTIVES: In our study, we focussed on three SNPs in the non-coding regions near FGFR2 gene, as studies on non-coding variants in the genome are the novel trends to identify the susceptible loci for nonsyndromic cleft lip with or without cleft palate (NSCL/P). FGFR2 gene is selected as a candidate gene based on knock out animal models and the role played in syndromic forms of clefting. FGFR2 gene also plays an important role in FGF signaling pathway during craniofacial development. METHODS: In the present study 148 case-parent triads were assessed for three SNPs rs10749408, rs11199874 and rs10788165 near FGFR2 gene by using TaqMan allelic discrimination method. Transmission disequilibrium test (TDT) was used to find the allelic association. Linkage disequilibrium (LD) between the markers was analysed using Haploview program 4.2. Haplotype transmission effects were estimated using FAMHAP package. The possible parent-of-origin effects were assessed by likelihood based approach. RESULTS: TDT analysis of three SNPs failed to show significant transmission disortion from heterozygous parents to the affected child and are not associated with NSCL/P. Linkage disequilibrium analysis showed strong LD between rs11199874 and rs10788165 SNPs. In the haplotype TDT analysis, GG haplotype of rs11199874-rs10788165 showed significant undertransmission to affected child. No significant parent-of-origin effects were observed. CONCLUSION: The present study on noncoding variants near FGFR2 gene is not associated with NSCL/P. As the numbers of triads included in the study are less, further studies are needed including large sample size to find association with NSCL/P.
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Fenda Labial , Fissura Palatina , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos , Criança , Fenda Labial/genética , Fissura Palatina/genética , Predisposição Genética para Doença , Genótipo , Haplótipos , Humanos , Funções Verossimilhança , Polimorfismo de Nucleotídeo Único , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genéticaRESUMO
The increase in incidence of prostate cancer in the Indian Population stresses the need to identify genetic markers for susceptibility and prognosis. Recent studies show that microRNAs play an important role in tumorigenesis by altering proliferation, differentiation and cell death. Gene polymorphisms not only in promoter region but also within miRNA gene have been shown to affect expression. The present study was aimed to analyze the role of miR-146a, miR-196a2 and miR-125a gene polymorphisms in prostate cancer. Genotyping of three SNPs rs73318382, rs57095329, rs2910164 in miRNA146a, rs11614913 in miR-196a2 and rs41275794, rs12976445, rs10404453 and rs1297533 in miR-125a was performed in 100 cases and 100 controls. Statistical analysis revealed the heterozygous AG genotype of the rs57095329 was significantly decreased in the cases when compared to the controls (OR-0.45, CI -0.24 to 0.85, p value-0.02) indicating an inverse association of this genotype with prostate cancer. Further the heterozygous CT of miR-196a2 (rs11614913) (OR-1.88, CI-1.06 to 3.35, p-0.02) and homozygous CC of miR-125a (rs12976445) (OR-2.55, CI -1.15 to 4.65, p-0.03) showed increased risk for prostate cancer. Combined analysis of all the genotypes revealed that the haplotype combination AGGCGTGG (OR = 0.09 at CI 95% (0.01-0.65) showed an inverse association with prostate cancer. Stratified analysis based on the age and tumor grade revealed no significant association.
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Predisposição Genética para Doença/genética , MicroRNAs/genética , Polimorfismo de Nucleotídeo Único , Neoplasias da Próstata/genética , Idoso , Povo Asiático/genética , Biomarcadores Tumorais/genética , Genótipo , Haplótipos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/patologia , RiscoRESUMO
AIM: Acanthosis nigricans (AN) is a strong correlate of obesity and is considered a marker of insulin resistance (IR). AN is associated with various other cardiometabolic risk factors (CMRFs). However, the direct causal relationship of IR with AN in obesity has been debated. Therefore, we aimed to examine the complex causal relationships among the troika of AN, obesity, and IR in Mexican Americans (MAs). METHODS: We used data from 670 non-diabetic MA children, aged 6-17 years (49% girls). AN (prevalence 33%) severity scores (range 0-5) were used as a quasi-quantitative trait (AN-q) for analysis. We used the program SOLAR for determining phenotypic, genetic, and environmental correlations between AN-q and CMRFs (e.g., BMI, HOMA-IR, lipids, blood pressure, hs-C-reactive protein (CRP), and Harvard physical fitness score (PFS)). The genetic and environmental correlations were subsequently used in mediation analysis (AMOS program). Model comparisons were made using goodness-of-fit indexes. RESULTS: Heritability of AN-q was 0.75 (p<0.0001). It was positively/significantly (p<0.05) correlated with traits such as BMI, HOMA-IR, and CRP, and negatively with HDL-C and PFS. Of the models tested, indirect mediation analysis of BMIâHOMA-IRâAN-q yielded lower goodness-of-fit than a partial mediation model where BMI explained the relationship with both HOMA-IR and AN-q simultaneously. Using complex models, BMI was associated with AN-q and IR mediating most of the CMRFs; but no relationship between IR and AN-q. CONCLUSION: Our study suggests that obesity explains the association of IR with AN, but no causal relationship between IR and AN in Mexican American children.
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Acantose Nigricans/fisiopatologia , Doenças Cardiovasculares/etiologia , Resistência à Insulina , Síndrome Metabólica/etiologia , Americanos Mexicanos/estatística & dados numéricos , Obesidade/epidemiologia , Adolescente , Biomarcadores/metabolismo , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/patologia , Criança , Feminino , Humanos , Incidência , Masculino , Síndrome Metabólica/metabolismo , Síndrome Metabólica/patologia , Obesidade/complicações , Estados Unidos/epidemiologiaRESUMO
During the course of cancer radiation treatment, normal skin invariably suffers from the cytotoxic effects of gamma-radiation and reactive oxygen species (ROS), which are generated from the interaction between radiation and the water molecules in cells. The present study was designed to investigate the radioprotective role of alpha-lipoic acid (LA), an antioxidant on murine skin fibroblasts exposed to a single dose of 2, 4, 6, or 8Gy gamma-radiation. Irradiation of fibroblasts significantly increased ROS, nitric oxide, and lipid peroxidation (P < 0.001); all of these factors substantially decreased with 100 microM LA treatment. Hydroxyl radical (OH(.)) production from 8Gy irradiated fibroblasts was measured directly by electron spin resonance using spin-trapping techniques. LA was found to inhibit OH(.) production at 100-microM concentrations. Dose-dependent depletion of antioxidants, such as catalase and glutathione reductase, was observed in irradiated fibroblasts (P < 0.001), along with increased superoxide dismutase (P < 0.001). LA treatment restored antioxidant levels. Concentration of the pro-inflammatory cytokine IL-1beta was significantly reduced in irradiated fibroblasts when treated with LA. MTT and lactate dehydrogenase assays demonstrated that LA treatment reduced cell injury and protected cells against irradiation-induced cytotoxicity. Thus, we conclude that results are encouraging and need further experiments to demonstrate a possible benefit in cancer patients and the reduction of harmful effects of radiation therapy.
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Antioxidantes/farmacologia , Fibroblastos/efeitos dos fármacos , Protetores contra Radiação/farmacologia , Pele/efeitos dos fármacos , Ácido Tióctico/farmacologia , Animais , Catalase/metabolismo , Células Cultivadas , Espectroscopia de Ressonância de Spin Eletrônica , Fibroblastos/metabolismo , Fibroblastos/efeitos da radiação , Raios gama/efeitos adversos , Glutationa Redutase/metabolismo , Radical Hidroxila/metabolismo , Interleucina-1beta/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Camundongos , Óxido Nítrico , Espécies Reativas de Oxigênio/metabolismo , Pele/citologia , Pele/efeitos da radiação , Superóxido Dismutase/metabolismoRESUMO
BACKGROUND: The aim of this meta-analysis was to determine the association of common type 1 diabetes (T1D) and type 2 diabetes (T2D) gene variants (protein tyrosine phosphatase non-receptor 22 [PTPN22] rs2476601C/T, insulin [INS] rs689A/T and transcription factor 7-like 2 [TCF7L2] rs7903146C/T) with latent autoimmune diabetes in adults (LADA). METHODS: A systematic search of electronic databases was conducted up to 2017 and data from 16 independent case-control studies for three gene variants were pooled. The pooled allele and genotype frequencies for each T1D and T2D gene variant were used to calculate odds ratios (ORs) with 95% confidence intervals (CIs) to assess the strength of the association. Heterogeneity tests and evaluation of publication bias were performed for all studies. RESULTS: In all, 8869 cases and 20 829 controls pooled from 16 case-control studies were included in the analysis. For rs2476601, a significant association was found for homozygote TT (OR 2.67; 95% CI 1.92-3.70; P < 0.0001), heterozygote CT (OR 1.61; 95% CI 1.44-1.79; P < 0.0001), and the T allele (OR 1.62; 95% CI 1.48-1.78; P < 0.0001). Overall, a significant inverse association was observed for rs689 in the TT genotype (OR 0.43; 95% CI 0.30-0.64; P < 0.0001), AT genotype (OR 0.53; 95% CI 0.45-0.62; P < 0.0001), and T allele (OR 0.61; 95% CI 0.52-0.71; P < 0.0001). For the rs7903146 polymorphism, the T allele (OR 1.19; 95% CI 1.00-1.40; P = 0.04) may be associated with the risk of LADA. CONCLUSION: The rs2476601C/T, rs689A/T, and rs7903146C/T polymorphisms were found to be associated with the risk of LADA, thereby indicating that, genetically, LADA could be an admixture of both T1D and T2D.
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Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 2/genética , Insulina/genética , Diabetes Autoimune Latente em Adultos/genética , Polimorfismo de Nucleotídeo Único , Proteína Tirosina Fosfatase não Receptora Tipo 22/genética , Proteína 2 Semelhante ao Fator 7 de Transcrição/genética , Adulto , Biomarcadores/análise , Estudos de Casos e Controles , Diabetes Mellitus Tipo 1/patologia , Diabetes Mellitus Tipo 2/patologia , Seguimentos , Predisposição Genética para Doença , Genótipo , Humanos , Diabetes Autoimune Latente em Adultos/patologia , PrognósticoRESUMO
Bleomycin is a chemotherapeutic and a radiomimetic drug which induces single and double-strand breaks in DNA by forming free radicals. We demonstrate in this study the capacity of bleomycin in inducing complex chromosome- and chromatid-type aberrations. Human peripheral blood was exposed to different concentrations of bleomycin (0, 10, 20, 30 and 40⯵g/mL) and the aberrations induced were studied. The chromosomal-type aberrations studied were dicentrics, tricentrics, tetracentrics, centric rings and acentric fragments. The chromatid-type aberrations studied were double minutes, terminal lesions and terminal deletions. Though the overall trends that we obtained in the dose-dependent mitotic index and the chromosome- and chromatid-type aberrations conform to the reported literature, we could observe enhanced numbers and the types of such damages in this study. We could notice that chromosome-type aberrations were more than the chromatid-type aberrations. The enhanced numbers and the types of aberrations induced pave way for enhancing the sensitivity of genotoxic assays. Also, with more numbers and type of aberrations available, it would be useful to study the mechanisms of genotoxicity of drugs and in understanding phenomena such as "tolerance induction" to chronic exposure to such mutagens.
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Antibióticos Antineoplásicos/toxicidade , Bleomicina/toxicidade , Aberrações Cromossômicas/induzido quimicamente , Linfócitos/efeitos dos fármacos , Mutagênicos/toxicidade , Células Cultivadas , Cromátides , Humanos , Linfócitos/metabolismo , Índice MitóticoRESUMO
Purpose: It is important to understand the significance of alpha (α) radiation-induced bystander effects (RIBE) and its relative biological effectiveness (RBE); this is because the phenomenon is not universal and the mechanism is unclear and because the RBE is widely varying and projected to be very high. Materials and methods: Isolated lymphocytes from healthy volunteers (n = 10) were exposed to either low fluence α-particles (241Am), γ-rays (60Co), or X-rays (225 kVp and 6 MV). Co-culture methodology was employed to investigate bystander effects (BEs). Chromosomal aberrations (CA) and micronucleus (MN) formation were used to study the BE and calculated RBE. Results: Lymphocytes directly exposed to the types of radiation used showed a dose-dependent increase in the frequency of CA and MN; dose independent increases in the frequency of these chromosomal damages in co-cultured bystander cells, implies that all three types of radiation-induced a BE. The calculated RBE at the level of 5% induced aberrations varied between 9 and 20. Conclusion: The magnitude of low fluence α-particle induced RIBE is higher than in low LET (linear energy transfer) radiation. The RBE also varies depending upon the endpoints used and adds up to targeted effects. Since the endpoint of CA is considered as an important and early marker of risk prediction, the RIBE and RBE using CA as a marker are relevant for radiation protection purposes.
Assuntos
Partículas alfa/efeitos adversos , Amerício/efeitos adversos , Efeito Espectador/efeitos da radiação , Aberrações Cromossômicas/efeitos da radiação , Linfócitos/metabolismo , Linfócitos/efeitos da radiação , Humanos , Linfócitos/citologia , Metáfase/genética , Metáfase/efeitos da radiação , Testes para Micronúcleos , Raios X/efeitos adversosRESUMO
Occupational heat stress apart from adverse heat-related health consequences also induces DNA damage in workers exposed to high working temperatures. We investigated the association between chronic heat exposures and Micronuclei (MN) frequency in lymphocytes of 120 workers employed in the steel industry. There was a significant increase in the MN-frequency in exposed workers compared to the unexposed workers (X2 = 47.1; p < 0.0001). While exposed workers had higher risk of DNA damage (Adj. OR = 23.3, 95% CI 8.0-70.8) compared to the unexposed workers, among the exposed workers, the odds of DNA damage was much higher for the workers exposed to high-heat levels (Adj. OR = 81.4; 95% CI 21.3-310.1) even after adjusting for confounders. For exposed workers, years of exposure to heat also had a significant association with higher induction of MN (Adj. OR = 29.7; 95% CI 2.8-315.5). Exposures to chronic heat stress is a significant occupational health risk including damages in sub-cellular level, for workers. Developing protective interventions to reduce heat exposures is imperative in the rising temperature scenario to protect millions of workers across the globe.
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Risk of cancer especially of colon, breast, and pancreas is high in diabetic and obese patients, with potential involvement of augmented expression of RAGE (receptor for advanced glycation end products) and its ligands, namely AGEs (advanced glycation end products), HMGB1 (high-mobility group box 1 protein), and S100 group of proteins. Studies have reported the involvement of RAGE activation by its ligands in growth and survival of cancers, including metastasis and poor prognosis. We propose that this receptor-ligand axis provides the molecular link between certain pre-existing states as hypoxia, hyperglycemia, glycation, inflammation, oxidative stress, and onset of cancers. The chronic inflammatory, hyperglycemic milieu accompanied by glycoxidative stress as in diabetes and obesity, concomitant with the formation of RAGE ligands, instigates RAGE and cancer stem cells, leading to the oncogenic transformation of normal and pre-malignant tissues towards development of neoplasms. We have aimed to elucidate the complete signalling map initiated upon RAGE-ligand splicing, from oncogenesis to progression, epithelial-mesenchymal transition, invasion, cancer stem cell renewal, chemo-resistance, and cancer relapse. We have attributed the complex molecular functions of RAGE-ligand signalling cues to every aspect of cancer promotion, explaining the central network in bridging glycation, inflammation, oxidation, and the hallmarks of cancer. Underlining the substantial requisite for anti-neoplastic agents targeting RAGE and its ligands, we have explicitly discoursed RAGE and its allied components (AGEs, soluble RAGE, RAGE gene polymorphisms) as potential diagnostic and prognostic biomarkers for prompt detection of cancers and implication in impending RAGE-ligand directed, novel combinatorial, and targeted onco-therapeutics.
Assuntos
Inflamação/genética , Neoplasias/genética , Receptor para Produtos Finais de Glicação Avançada/genética , Humanos , Neoplasias/patologiaRESUMO
This study was carried out to determine the chemoprotective potential of a polyherbal aqueous decoction comprised of Nigella sativa (seeds), Hemidesmus indicus (roots), and Smilax glabra (rhizome) against bleomycin induced cytogenetic damage in human lymphocytes. Isolated peripheral blood lymphocytes (PBLs) were exposed to bleomycin at a dose of 40 µg/mL for 2 hrs in the presence or absence of different doses of the decoction (100, 300, and 600 µg/mL). Modulatory effect of the decoction on bleomycin induced cytogenetic damage was evaluated by (a) degree of chromosomal aberrations (CA), (b) formation of micronuclei (MN), and (c) induction of γH2AX foci in lymphocytes exposed to bleomycin. Lymphocytes pretreated with the decoction showed that a significant reduction (p < 0.05) in bleomycin induced (a) stable and unstable chromosome aberrations (CA), (b) MN formation, and (c) formation of γH2AX foci, when compared to lymphocytes treated only with bleomycin. The decoction by itself did not induce any significant cytogenetic damage in PBLs. Overall results of the present study confirm that the decoction can attenuate the cytogenetic damage mediated by bleomycin in human PBLs.
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Bleomicina/efeitos adversos , Aberrações Cromossômicas/induzido quimicamente , Hemidesmus/química , Linfócitos/metabolismo , Nigella sativa/química , Extratos Vegetais/farmacologia , Rizoma/química , Sementes/química , Smilax/química , Bleomicina/farmacologia , Humanos , Linfócitos/patologia , Extratos Vegetais/químicaRESUMO
OBJECTIVES: Transforming growth factor beta1 (TGF-ß1) plays a significant role in craniofacial development. Previous linkage studies reported that the TGF-ß1-locus at 19q13.1 harbour predisposing genes for non-syndromic oral clefts. In the present study case parents triads were evaluated to find the transmission effects of genetic variants in TGF- ß1 towards non-syndromic cleft lip or palate (NSCL/P). METHODS: Using allelic discrimination method148 families (case-parent triads) were assessed for single nucleotide polymorphisms (SNPs) in TGF-ß1 gene. The SNPs were checked for mendelian errors and Hardy-Weinberg equilibrium (HWE). Transmission disequilibrium test and haplotype frequencies were estimated. RESULTS: The TGF-ß1 SNPs showed very low minor allele frequencies (MAFs) and observed heterozygosity (Hobs). The transmission disequilibrium test (TDT) and parent-of-origin likelihood ratio tests (PO-LRT) were not significant for any of the SNPs tested. Strong linkage disequilibrium (r2 = 0.722) was found between rs1800469 and rs1800470 SNPs. Haplotype analysis ignoring parent of origin showed strong evidence of excess transmission but it is not significant (p-value = 0.293). CONCLUSION: Transmission of minor alleles were not observed from either parent indicating that the TGF-ß1 gene polymorphisms by themselves do not confer risk for non-syndromic oral clefts but, rather, modify the stability and the activation process of TGF-ß1. As the number of families included in the study are less, results must be considered still preliminary and require replication using more families.