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1.
Sci Rep ; 14(1): 18413, 2024 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-39117733

RESUMO

Cancer therapy-related cardiac dysfunction (CTRCD), which commonly includes left ventricular dysfunction and heart failure, is the main adverse effect of anticancer therapy. In recent years several candidate genes studies and genome-wide association studies have identified common genetic variants associated with CTRCD, but evidence remains limited and few genetic variants are robust. A genome-wide meta-analysis of CTRCD was performed with 852 oncology patients receiving cancer therapy. DNA samples were genotyped and imputed to perform a GWAS meta-analysis for case-control (N = 852 (380 cases and 472 controls) and extreme phenotypes (N = 618 (78 cases and 472 controls) looking for genetic variants that predispose to CTRCD. The results were validated in a replicate cohort of 1,191 oncology patients (245 cases and 946 controls). Functional mapping of the replicated loci was then performed. The meta-analysis showed 9 and 17 loci suggestively associated (P-value < 1 × 10-5) with CTRCD in case-control and extreme phenotypes analyses, respectively. The 3q28 locus (rs rs7652759, P = 5.64 × 10-6) in the case-control analysis was the strongest signal, with up to 64 SNPs above the suggestive significance threshold. The rs7652759, an intergenic variant between TPRG1 and TP63 genes, was the only variant validated in the replication cohort (P-value = 0.01). Functional mapping of this significant locus revealed up to 5 new genes potentially involved in the CTRCD. We identified the intergenic region near TP63 as a novel CTRCD susceptibility locus. In the future, the genotyping of these markers could be considered in new CTRCD risk scores to improve preventive strategies in cardio-oncology.


Assuntos
Estudo de Associação Genômica Ampla , Neoplasias , Polimorfismo de Nucleotídeo Único , Proteínas Supressoras de Tumor , Humanos , Proteínas Supressoras de Tumor/genética , Neoplasias/genética , Neoplasias/tratamento farmacológico , Feminino , Masculino , Predisposição Genética para Doença , Fatores de Transcrição/genética , Estudos de Casos e Controles , DNA Intergênico/genética , Pessoa de Meia-Idade , Idoso , Mapeamento Cromossômico
2.
Sci Rep ; 12(1): 8547, 2022 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-35595798

RESUMO

Only up to 25% of the cases in which there is a familial aggregation of breast and/or ovarian cancer are explained by germline mutations in the well-known BRCA1 and BRCA2 high-risk genes. Recently, the BRCA1-associated ring domain (BARD1), that partners BRCA1 in DNA repair, has been confirmed as a moderate-risk breast cancer susceptibility gene. Taking advantage of next-generation sequencing techniques, and with the purpose of defining the whole spectrum of possible pathogenic variants (PVs) in this gene, here we have performed a comprehensive mutational analysis of BARD1 in a cohort of 1946 Spanish patients who fulfilled criteria to be tested for germline pathogenic mutations in BRCA1 and BRCA2. We identified 22 different rare germline variants, being 5 of them clearly pathogenic or likely pathogenic large deletions, which account for 0.26% of the patients tested. Our results show that the prevalence and spectrum of mutations in the BARD1 gene might vary between different regions of Spain and expose the relevance to test for copy number variations.


Assuntos
Neoplasias da Mama , Variações do Número de Cópias de DNA , Neoplasias Ovarianas , Proteínas Supressoras de Tumor , Ubiquitina-Proteína Ligases , Proteína BRCA1/genética , Neoplasias da Mama/genética , Variações do Número de Cópias de DNA/genética , Feminino , Genes BRCA1 , Genes BRCA2 , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Humanos , Neoplasias Ovarianas/genética , Espanha/epidemiologia , Proteínas Supressoras de Tumor/genética , Ubiquitina-Proteína Ligases/genética
3.
BMC Cancer ; 20(1): 1079, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33167914

RESUMO

BACKGROUND: In recent years, the identification of genetic and phenotypic biomarkers of cancer for prevention, early diagnosis and patient stratification has been a main objective of research in the field. Different multivariable models that use biomarkers have been proposed for the evaluation of individual risk of developing breast cancer. METHODS: This is a case control study based on a population-based cohort. We describe and evaluate a multivariable model that incorporates 92 Single-nucleotide polymorphisms (SNPs) (Supplementary Table S1) and five different phenotypic variables and which was employed in a Spanish population of 642 healthy women and 455 breast cancer patients. RESULTS: Our model allowed us to stratify two groups: high and low risk of developing breast cancer. The 9th decile included 1% of controls vs 9% of cases, with an odds ratio (OR) of 12.9 and a p-value of 3.43E-07. The first decile presented an inverse proportion: 1% of cases and 9% of controls, with an OR of 0.097 and a p-value of 1.86E-08. CONCLUSIONS: These results indicate the capacity of our multivariable model to stratify women according to their risk of developing breast cancer. The major limitation of our analysis is the small cohort size. However, despite the limitations, the results of our analysis provide proof of concept in a poorly studied population, and opens up the possibility of using this method in the routine screening of the Spanish population.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/epidemiologia , Predisposição Genética para Doença , Fenótipo , Polimorfismo de Nucleotídeo Único , Medição de Risco/métodos , Adulto , Idoso , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Estudos de Casos e Controles , Feminino , Seguimentos , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Pessoa de Meia-Idade , Prognóstico , Espanha/epidemiologia , Adulto Jovem
5.
J Transl Med ; 17(1): 75, 2019 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-30871557

RESUMO

BACKGROUND: Extracellular vesicles (EVs) are small membrane-bound vesicles which play an important role in cell-to-cell communication. Their molecular cargo analysis is presented as a new source for biomarker detection, and it might provide an alternative to traditional solid biopsies. However, the most effective approach for EV isolation is not yet well established. RESULTS: Here, we study the efficiency of the most common EV isolation methods-ultracentrifugation, Polyethlyene glycol and two commercial kits, Exoquick® and PureExo®. We isolated circulating EVs from the bloodstream of healthy donors, characterized the size and yield of EVs and analyzed their protein profiles and concentration. Moreover, we have used for the first time Digital-PCR to identify and detect specific gDNA sequences, which has several implications for diagnostic and monitoring many types of diseases. CONCLUSIONS: Our findings present Polyethylene glycol precipitation as the most feasible and less cost-consuming EV isolation technique.


Assuntos
Ácidos Nucleicos Livres/isolamento & purificação , Vesículas Extracelulares/metabolismo , Polietilenoglicóis/farmacologia , Biomarcadores/metabolismo , Ácidos Nucleicos Livres/genética , Precipitação Química , Exossomos/metabolismo , Humanos , Tamanho da Partícula
6.
Artigo em Inglês | MEDLINE | ID: mdl-30151018

RESUMO

The oxidative stress is characterized by an imbalance between the oxidizing agents and antioxidants; meanwhile, the consumption of antioxidants has been considered as an important tool in the prevention of oxidative stress and its consequences. Pitavia punctata (R. & P.) Molina is an endemic arboreal species from the Chilean Coast Range, in which a large amount of flavonoids has been described. This work focused on characterizing and evaluating, in human erythrocytes, the antioxidant capacity and membrane protection of P. punctata extracts and the in vitro protection of the oxidation of the Low Density Lipoprotein (LDL). The phytochemical screening revealed the presence of Quercetin derivatives and flavonoids, such as (-)-Epicatechin, Kaempferol, and derivatives. The methanolic extract presented an important antioxidant activity, protecting the membrane integrity of the red blood cells against the oxidative damage caused by Hypochlorous acid and inhibiting the oxidation of the LDL lipoprotein.

7.
Food Res Int ; 102: 341-347, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29195957

RESUMO

Astringency is a tactile sensation that is generated by a reduction in lubrication in the oral cavity and is generally attributed to the interaction of procyanidins or condensed tannins with salivary proteins. Several factors influence tannin-protein interactions, such as pH, alcohol, sweetness, oxygen and polyphenol content. A scarcely studied factor is the effect of the tannin content on the perception of astringency. The objective of this study was to evaluate the effect of different concentrations of commercial oenological tannin (COT) on the timing of the perception of astringency. For this model, a vinous solution enriched with three concentrations of COT was used. The samples were subjected to a storage period of three months. Additionally, a panel was trained in the perception of astringency in red wines using a method of temporal dominance of sensations (TDS). Astringency descriptors were selected, and the TDS method was used to characterize the astringency. The samples were evaluated using traditional descriptors in TDS and astringency descriptors in TDS. In traditional TDS curves, treatments with higher concentrations of COT showed a higher and more persistent dominance index in the descriptor astringency. Moreover, the stimulus duration variable increased as the COT level increased. Likewise, temporary astringency was dominant over alcohol. For astringency TDS, at low concentrations of COT, the soft and adhesive descriptors were dominant, whereas at high COT concentrations, aggressive and drying were perceived as the dominant descriptors. An increasing concentration of tannin in the vinous solution generated an increased duration and dominance of astringency and reduced the duration of the sensation of alcohol. Finally, the type of perceived astringency was closely related to the tannin concentration.


Assuntos
Adstringentes/análise , Qualidade dos Alimentos , Sensação , Taninos/análise , Água/análise , Vinho/análise , Adstringentes/química , Cromatografia Líquida de Alta Pressão , Humanos , Espectrofotometria Ultravioleta , Taninos/química
8.
Anim Genet ; 48(3): 353-357, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28094447

RESUMO

Local chicken populations are a major source of food in the rural areas of South America. However, very little is known about their genetic composition and diversity. Here, we analyzed five populations from South America to investigate their maternal genetic origin and diversity, hoping to mitigate the lack of information on local chicken populations from this region. We also included three populations of chicken from the Iberian Peninsula and one from Easter Island, which are potential sources of the first chickens introduced in South America. The obtained sequencing data from South American chickens indicate the presence of four haplogroups (A, B, E and D) that can be further subdivided into nine sub-haplogroups. Of these, four (B1, D1a, E1a(b), E1b) were absent from local Iberian Peninsula chickens and one (D1a) was present only on Easter Island. The presence of the sub-haplogroups A1a(b) and E1a(b) in South America, previously only observed in Eastern Asia, and the significant population differentiation between Iberian Peninsula and South American populations, suggest a second maternal source of the extant genetic pool in South American chickens.


Assuntos
Galinhas/genética , Variação Genética , Genética Populacional , Animais , DNA Mitocondrial/genética , Pool Gênico , Haplótipos , Filogenia , Análise de Sequência de DNA/veterinária , América do Sul
9.
Ann Oncol ; 27(9): 1788-93, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27287205

RESUMO

BACKGROUND: Despite the effectiveness of current treatment protocols for Ewing sarcoma (ES), many patients still experience relapse, and survival following recurrence is <15%. We aimed to identify genetic variants that predict treatment outcome in children diagnosed with ES. PATIENTS AND METHODS: We carried out a pharmacogenetic study of 384 single-nucleotide polymorphisms (SNPs) in 24 key transport or metabolism genes relevant to drugs used to treat in pediatric patients (<30 years) with histologically confirmed ES. We studied the association of genotypes with tumor response and overall survival (OS) in a discovery cohort of 106 Spanish children, with replication in a second cohort of 389 pediatric patients from across Europe. RESULTS: We identified associations with OS (P < 0.05) for three SNPs in the Spanish cohort that were replicated in the European cohort. The strongest association observed was with rs7190447, located in the ATP-binding cassette subfamily C member 6 (ABCC6) gene [discovery: hazard ratio (HR) = 14.30, 95% confidence interval (CI) = 1.53-134, P = 0.020; replication: HR = 9.28, 95% CI = 2.20-39.2, P = 0.0024] and its correlated SNP rs7192303, which was predicted to have a plausible regulatory function. We also replicated associations with rs4148737 in the ATP-binding cassette subfamily B member 1 (ABCB1) gene (discovery: HR = 2.96, 95% CI = 1.08-8.10, P = 0.034; replication: HR = 1.60, 95% CI = 1.05-2.44, P = 0.029), which we have previously found to be associated with poorer OS in pediatric osteosarcoma patients, and rs11188147 in cytochrome P450 family 2 subfamily C member 8 gene (CYP2C8) (discovery : HR = 2.49, 95% CI = 1.06-5.87, P = 0.037; replication: HR = 1.77, 95% CI = 1.06-2.96, P = 0.030), an enzyme involved in the oxidative metabolism of the ES chemotherapeutic agents cyclophosphamide and ifosfamide. None of the associations with tumor response were replicated. CONCLUSION: Using an integrated pathway-based approach, we identified polymorphisms in ABCC6, ABCB1 and CYP2C8 associated with OS. These associations were replicated in a large independent cohort, highlighting the importance of pharmacokinetic genes as prognostic markers in ES.


Assuntos
Citocromo P-450 CYP2C8/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Sarcoma de Ewing/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Estudos de Associação Genética , Genótipo , Humanos , Lactente , Masculino , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/patologia , Polimorfismo de Nucleotídeo Único , Sarcoma de Ewing/tratamento farmacológico , Sarcoma de Ewing/patologia , Análise de Sobrevida , Resultado do Tratamento , Adulto Jovem
10.
Food Chem ; 207: 261-71, 2016 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-27080904

RESUMO

The volatile compositions of Charmat and traditional Chilean sparkling wines were studied for the first time. For this purpose, EG-Silicone and PDMS polymeric phases were compared and, afterwards, the most adequate was selected. The best extraction method turned out to be a sequential extraction in the headspace and by immersion using two PDMS twisters. A total of 130 compounds were determined. In traditional Chilean sparkling wines, ethyl esters were significantly higher, while acetic esters and ketones were predominant in the Charmat wines. PCA and LDA confirmed the differences in the volatile profiles between the production methods (traditional vs. Charmat).


Assuntos
Compostos Orgânicos Voláteis/análise , Vinho/análise , Chile , Ésteres/análise , Indústria Alimentícia , Cetonas/análise
11.
Theriogenology ; 84(7): 1053-60, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-26279312

RESUMO

The aim of this study was to develop an in vitro embryo culture medium without either fetal calf serum or BSA, using various growth factors and cytokines (GFs-CYKs; IGF-I, IGF-II, bFGF, LIF, GM-CSF, TGF-ß1, and PDGF-BB), and other molecules with surfactant and embryotrophic properties, such as recombinant albumin (RA) and hyaluronan (HA). The first part of the study was dedicated to define the best combination of GFs-CYKs + RA + HA for optimal embryonic development. Next, we compared development rates and embryo quality (inner cell mass [ICM]-to-total cell number [TCN] ratio), and postthaw survival and hatching rates using this synthetic medium (T1) and a control medium: synthetic oviduct fluid + BSA + ITS (insulin, transferrin, and selenium). The blastocyst rates were significantly higher with T1 than those with the control at 7 and 8 days after fertilization. There was no significant difference in TCN or the ICM/TCN ratio between the two treatments. Survival and hatching rates 48 hours after thawing were similar for both treatments. Finally, nine embryo transfers were conducted using fresh and previously frozen Day-7 blastocysts to evaluate the in vivo viability of embryos produced in this synthetic medium; four gestations were obtained from six fresh embryos and one gestation from three frozen embryos. In conclusion, the fetal calf serum and BSA-free medium, supplemented with GFs-CYKs + RA + HA, improved embryo development and gave comparable ICM/TCN ratios and postthaw survival rates to the control with BSA. Fresh and frozen embryos produced in this medium are viable for embryo transfer. This fully synthetic method of embryo culture is a useful means of reducing the risk of disease transmission via embryo transfer.


Assuntos
Bovinos/embriologia , Meios de Cultura , Técnicas de Cultura Embrionária/veterinária , Fertilização in vitro/veterinária , Albuminas , Animais , Blastocisto/fisiologia , Criopreservação , Meios de Cultura/química , Citocinas , Técnicas de Cultura Embrionária/métodos , Transferência Embrionária/veterinária , Desenvolvimento Embrionário , Feminino , Ácido Hialurônico , Peptídeos e Proteínas de Sinalização Intercelular , Gravidez , Proteínas Recombinantes , Tensoativos
12.
J Gastroenterol ; 50(6): 657-66, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25381643

RESUMO

BACKGROUND: Familial colorectal cancer type X (FCCTX) fulfils clinical criteria defining Lynch syndrome (LS), but is not related to germline mutations in DNA mismatch-repair genes. Its aetiology remains unexplained and there is little evidence of involvement of the common colorectal carcinogenetic pathways. We aimed to identify susceptibility loci and gain insights into carcinogenic pathways involved FCCTX tumour development. METHODS: We performed a linkage analysis in 22 FCCTX families. We also constructed a tissue microarray in order to define an immunohistochemical (IHC) profile for FCCTX tumours (N = 27) by comparing them to three other types of colorectal tumors: LS (N = 18), stable early-onset (N = 31) and other sporadic disease (N = 80). Additionally, we screened for BRAF/KRAS mutations and determined CpG island methylator phenotype (CIMP) status for all FCCTX tumours. RESULTS: We found suggestive evidence of linkage at four chromosomal regions; 2p24.3, 4q13.1, 4q31.21 and 12q21.2-q21.31. We screened genes in 12q21 and ruled out the implication of RASSF9 and NTS, good candidates due to their potential involvement in carcinogenesis and colorectal epithelium development. Based on IHC profiles FCCTX tumours did not form a single, exclusive cluster. They were clearly different from LS, but very similar to stable early onset tumours. The CIMP and chromosomal instability pathways were implicated in one-third and one-quarter of FCCTX cases, respectively. The remaining cases did not have alterations in any known carcinogenic pathways. CONCLUSIONS: Our results highlight the heterogeneity of FCCTX tumours and call into question the utility of using only clinical criteria to identify FCCTX cases.


Assuntos
Neoplasias Colorretais Hereditárias sem Polipose/genética , Ligação Genética/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Instabilidade Cromossômica , Neoplasias Colorretais Hereditárias sem Polipose/patologia , Ilhas de CpG/genética , Estudo de Associação Genômica Ampla , Humanos , Pessoa de Meia-Idade , Mutação , Adulto Jovem
13.
Br J Cancer ; 110(4): 1088-100, 2014 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-24548884

RESUMO

BACKGROUND: Breast cancer is one of the most common malignancies in women. Genome-wide association studies have identified FGFR2 as a breast cancer susceptibility gene. Common variation in other fibroblast growth factor (FGF) receptors might also modify risk. We tested this hypothesis by studying genotyped single-nucleotide polymorphisms (SNPs) and imputed SNPs in FGFR1, FGFR3, FGFR4 and FGFRL1 in the Breast Cancer Association Consortium. METHODS: Data were combined from 49 studies, including 53 835 cases and 50 156 controls, of which 89 050 (46 450 cases and 42 600 controls) were of European ancestry, 12 893 (6269 cases and 6624 controls) of Asian and 2048 (1116 cases and 932 controls) of African ancestry. Associations with risk of breast cancer, overall and by disease sub-type, were assessed using unconditional logistic regression. RESULTS: Little evidence of association with breast cancer risk was observed for SNPs in the FGF receptor genes. The strongest evidence in European women was for rs743682 in FGFR3; the estimated per-allele odds ratio was 1.05 (95% confidence interval=1.02-1.09, P=0.0020), which is substantially lower than that observed for SNPs in FGFR2. CONCLUSION: Our results suggest that common variants in the other FGF receptors are not associated with risk of breast cancer to the degree observed for FGFR2.


Assuntos
Neoplasias da Mama/genética , Predisposição Genética para Doença , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Estudos de Casos e Controles , Feminino , Variação Genética , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único/genética , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 5 de Fator de Crescimento de Fibroblastos/genética
14.
Br J Cancer ; 105(12): 1934-9, 2011 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-22033276

RESUMO

BACKGROUND: Somatic mutations in phosphoinositide-3-kinase catalytic subunit alpha (PIK3CA) are frequent in breast tumours and have been associated with oestrogen receptor (ER) expression, human epidermal growth factor receptor-2 overexpression, lymph node metastasis and poor survival. The goal of this study was to evaluate the association between inherited variation in this oncogene and risk of breast cancer. METHODS: A single-nucleotide polymorphism from the PIK3CA locus that was associated with breast cancer in a study of Caucasian breast cancer cases and controls from the Mayo Clinic (MCBCS) was genotyped in 5436 cases and 5280 controls from the Cancer Genetic Markers of Susceptibility (CGEMS) study and in 30 949 cases and 29 788 controls from the Breast Cancer Association Consortium (BCAC). RESULTS: Rs1607237 was significantly associated with a decreased risk of breast cancer in MCBCS, CGEMS and all studies of white Europeans combined (odds ratio (OR)=0.97, 95% confidence interval (CI) 0.95-0.99, P=4.6 × 10(-3)), but did not reach significance in the BCAC replication study alone (OR=0.98, 95% CI 0.96-1.01, P=0.139). CONCLUSION: Common germline variation in PIK3CA does not have a strong influence on the risk of breast cancer.


Assuntos
Neoplasias da Mama/enzimologia , Predisposição Genética para Doença , Variação Genética , Fosfatidilinositol 3-Quinases/genética , Neoplasias da Mama/genética , Estudos de Casos e Controles , Classe I de Fosfatidilinositol 3-Quinases , Feminino , Humanos
15.
Pharmacogenomics J ; 9(5): 347-53, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19434073

RESUMO

Platinum agents cause DNA cross-linking. Nucleotide excision repair genes play a key role in DNA damage repair. This study aims to investigate whether polymorphisms in these genes are associated with tumor response and survival in cisplatin-treated osteosarcoma patients. Eight single nucleotide polymorphisms in ERCC2, XPC, XPA, ERCC1, ERCC4 and ERCC5 genes were analyzed in 91 patients diagnosed with osteosarcoma and treated with cisplatin. A significant association with tumor response, after correction for multiple testing, was found for the Lys751Gln polymorphism in the ERCC2 gene. We found that only 45% of patients with at least one polymorphic G allele responded compared with 80% of patients homozygous for the common T allele (odds ratio=4.9, 95% confidence interval=1.64-14.54, adjusted P-value=0.047). In addition, carrying at least one ERCC2 Lys751GlnG allele was significantly associated with shorter event-free survival (median=184 months, compared with 240 months for TT homozygotes; hazard ratio=5.76, 95% confidence interval=1.30-25.55; P-value=0.021). Although ototoxicity was only recorded in 32 patients, we found weak evidence of an association with the CC genotype of XPC Lys939Gln (P-value= 0.042). This is the first pharmacogenetic study focused on osteosarcoma treatment providing evidence that polymorphic variants in DNA repair genes could be useful predictors of response to cisplatin chemotherapy in osteosarcoma patients.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Cisplatino/uso terapêutico , Osteossarcoma/tratamento farmacológico , Polimorfismo de Nucleotídeo Único , Proteína Grupo D do Xeroderma Pigmentoso/genética , Adolescente , Adulto , Antineoplásicos/efeitos adversos , Neoplasias Ósseas/genética , Neoplasias Ósseas/mortalidade , Neoplasias Ósseas/patologia , Quimioterapia Adjuvante , Criança , Pré-Escolar , Cisplatino/efeitos adversos , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Frequência do Gene , Perda Auditiva/induzido quimicamente , Perda Auditiva/genética , Homozigoto , Humanos , Estimativa de Kaplan-Meier , Modelos Logísticos , Masculino , Osteossarcoma/genética , Osteossarcoma/mortalidade , Osteossarcoma/patologia , Seleção de Pacientes , Farmacogenética , Fenótipo , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Medição de Risco , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
16.
Ann Hum Genet ; 70(Pt 4): 459-87, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16759179

RESUMO

The Balkan Peninsula is a complex cultural mosaic comprising populations speaking languages from several branches of the Indo-European family and Altaic, as well as culturally-defined minorities such as the Aromuns who speak a Romance language. The current cultural and linguistic landscape is a palimpsest in which different peoples have contributed their cultures in a historical succession. We have sought to find any evidence of genetic stratification related to those cultural layers by typing both mtDNA and Y chromosomes, in Albanians, Romanians, Macedonians, Greeks, and five Aromun populations. We have paid special attention to the Aromuns, and sought to test genetically various hypotheses on their origins. MtDNA and Y-chromosome haplogroup frequencies in the Balkans were found to be similar to those elsewhere in Europe. MtDNA sequences and Y-chromosome STR haplotypes revealed decreased variation in some Aromun populations. Variation within Aromun populations was the primary source of genetic differentiation. Y-chromosome haplotypes tended to be shared across Aromuns, but not across non-Aromun populations. These results point to a possible common origin of the Aromuns, with drift acting to differentiate the separate Aromun communities. The homogeneity of Balkan populations prevented testing for the origin of the Aromuns, although a significant Roman contribution can be ruled out.


Assuntos
Cromossomos Humanos Y , DNA Mitocondrial , Variação Genética , Idioma , Emigração e Imigração , Europa Oriental , Deriva Genética , Marcadores Genéticos , Genética Populacional , Humanos , Masculino , Filogenia , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA
17.
Mol Psychiatry ; 11(1): 66-75, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16189508

RESUMO

Neuregulin 1 (NRG1) is one of the most exciting candidate genes for schizophrenia in recent years since its first association with the disease in an Icelandic population. Since then, many association studies have analysed allele and haplotype frequencies in distinct populations yielding varying results: some have replicated the association, although with different alleles or haplotypes being associated, whereas others have failed to replicate the association. These contradictory results might be attributed to population differences in allele and haplotype frequencies. In order to approach this issue, we have typed 13 SNPs across this large 1.4 Mb gene, including two of the SNPs originally found associated with schizophrenia in the Icelandic population, the objective being to discover if the underlying cause of the association discrepancies to date may be due to population-specific genetic variation. The analyses have been performed in a total of 1088 individuals from 39 populations, covering most of the genetic diversity in the human species. Most of the SNPs analysed displayed differing frequencies according to geographical region. These allele differences are especially relevant in two SNPs located in a large intron of the gene, as shown by the extreme F(ST) values, which reveal genetic stratification correlated to broad continental areas. This finding may be indicative of the influence of some local selective forces on this gene. Furthermore, haplotype analysis reveals a clear clustering according to geographical areas. In summary, our findings suggest that NRG1 presents extreme population differences in allele and haplotype frequencies. We have given recommendations for taking this into account in future association studies since this diversity could give rise to erroneous results.


Assuntos
Ligação Genética , Genoma Humano , Proteínas do Tecido Nervoso/genética , Polimorfismo de Nucleotídeo Único , Esquizofrenia/genética , Frequência do Gene , Variação Genética , Genética Populacional , Haplótipos , Humanos , Neuregulina-1
18.
Univ. med ; 46(4): 150-153, oct.-dic. 2005. ilus
Artigo em Espanhol | LILACS | ID: lil-501140

RESUMO

El divertículo de Meckel es una anormalidad congénita del tracto grastrointestinal debida a la falta del cierre del conducto onfalomesentérico y sus complicaciones son raras en los adultos. Se presenta el caso de un hombre de 35 años, quien después de la ingesta de alcohol presentó dolor abdominal y fallece repentinamente. Se le realiza autopsia y estudios histopatológicos donde se evidenció hemoperitoneo masivo originado por la erosión de vasos sanguíneos secundarios a la ulceración de la pared del divertículo de Meckel localizado en el intestino delgado. Esta causa de muerte es infrecuente debido a que la complicación másusual del divertículo es la obstrucción.


Assuntos
Humanos , Divertículo Ileal , Hemoperitônio , Trato Gastrointestinal
19.
J Med Entomol ; 41(2): 158-61, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15061273

RESUMO

The current study was performed on the Bioko Island (Equatorial Guinea) with the aim of establishing a rapid assessment technique for mapping malaria risk and measuring vector densities. Human bait collection, tent traps, light traps, indoor resting collection, and window exit traps were used to collect Anopheles gambiae s.s. and Anopheles funestus, the two anopheline species involved in malaria transmission in this island. Capture data were used to compare differences in the behavior and vectorial capacity of An. gambiae s.s. and An. funestus. Differences in the two species of mosquitoes were found in relation to the season and trapping methods used. Entomological inoculation rates (EIR) for Plasmodium falciparum were calculated using a polymerase chain reaction (PCR) test with individual anopheline mosquitoes from human bait collections in two villages during the dry and rainy seasons. P. falciparum sporozoites were detected from both dissected heads/thorax and abdomens of both species.


Assuntos
Anopheles/classificação , Insetos Vetores/classificação , Malária/epidemiologia , Malária/transmissão , Controle de Mosquitos/métodos , Animais , Clima , Guiné Equatorial , Feminino , Geografia , Humanos , Masculino , Fatores de Risco
20.
Am J Phys Anthropol ; 122(2): 147-61, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12949835

RESUMO

To investigate the diversity of Y chromosomes in the Iberian Peninsula and the North African population of Maghreb, we constructed superhaplotypes on the basis of 10 biallelic markers, 7 microsatellites, and 1 minisatellite located in the nonrecombining portion of the human Y chromosome. The analysis of extremely high MSY1 variability was performed by reducing the MVR-codes to modular structures. Y-STRs and MSY1 data provide information about the relationship between closely related populations such as those of Iberia. Analysis of biallelic markers allowed us to identify 7 of 12 haplogroups defined by those polymorphisms. The haplogroup background showed clear differences between Iberian populations and the North African one. The use of differently mutating Y-chromosome markers allowed us to infer different population events at different time scales: the Paleolithic background of the Iberian Peninsula, the Neolithic fingerprint on Y-chromosome lineages, and the Iron Age influence in the populations of Iberia. Implications of our results for the highly debated origin of Basques are also discussed.


Assuntos
Cromossomos Humanos Y , Marcadores Genéticos , Genética Populacional , Repetições Minissatélites , População Negra , Haplótipos , Humanos , Polimorfismo Genético , Espanha , População Branca
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