Acute coronary syndrome: Relationship between genetic variants and TIMI risk.

Acute Coronary Syndrome (ACS) is a multifactorial disease, including the genetic factor, caused by coronary artery obstruction by atheroma. Some genetic variants have been described as risk factors for this disease. Its early diagnosis and stratification of risk of death by Thrombolysis in Myocardial Infarction (TIMI) are important. Therefore, we evaluated variants in the IL6R (c950-1722C>T), TNFa (c.-488G>A), LEPR (c.2673+1118C>T) and IL1b (c.-598T>C) genes in relation to TIMI risk, cytokine serum levels, and risk factors for ACS. We selected 200 patients with ACS, 50 without ACS from the Real Hospital Português, Recife - PE, and 295 blood donors at the Fundação de Hematologia e Hemoterapia de Pernambuco (Hemope). Variants were determined by DNA sequencing or enzymatic cleavage. Cytokine levels were measured by ELISA. The most frequent risk factors found in the patients were dyslipidemia and hypertension, this latter associated with high TIMI risk (p = 0.003). Genotype frequencies of IL6R and TNFa differed between patients with ACS and the blood donors (p = 0.0002 and p = 0.01, respectively), and TNF-α levels differed between genotypes. The TT genotype of the IL6R gene is as a possible protective factor for ACS because it was significantly more present in blood donors (32.2%) than in patients with ACS (18.0%), and was more frequent in low TIMI risk (22.9%) than in the intermediate (20.2%) or high (4.9%). In patients with ACS, the TT genotype in IL6R was related to a lower concentration of c-reactive protein (p = 0.03) and troponin (p = 0.02), showing a less inflammatory reaction and tissue damage. The differences in the frequencies of variants in genes of medical interest among the groups show the importance of studies in specific populations groups to establish the relationship between genes and diseases.

Tyms double (2R) and triple repeat (3R) confers risk for human oral squamous cell carcinoma.

The oral cancer is responsible for approximately 3 % of cases of cancer in Brazil. Epidemiological studies have associated low folate intake with an increased risk of epithelial cancers, including oral cancer. Folic acid has a key role in DNA synthesis, repair, methylation and this is the basis of explanations for a putative role for folic acid in cancer prevention. The role of folic acid in carcinogenesis may be modulated by polymorphism C677T in MTHFR and tandem repeats 2R/3R in the promoter site of TYMS gene that are related to decreased enzymatic activity and quantity and availability of the enzyme, respectively. These events cause a decrease in the synthesis, repair and DNA methylation, which can lead to a disruption in the expression of tumor suppressor genes as TP53. The objective of this study was investigate the distribution of polymorphisms C677T and tandem repeats 2R/3R associated with the development of oral squamous cell carcinoma (OSCC). 53 paraffin-embedded samples from patients who underwent surgery but are no longer at the institution and 43 samples collected by method of oral exfoliation by cytobrush were selected. 132 healthy subjects were selected by specialists at the dental clinics of the Faculdade de Odontologia de Pernambuco-FOP. The MTHFR genotyping was performed by PCR-RFLP, and the TYMS genotyping was performed by conventional PCR. Fisher's Exact test at significant level of 5 %. Odds ratios (ORs) and 95 % confidence intervals (CIs) were used to measure the strength of association between genotype frequency and OSCC development. The results were statistically significant for the tandem repeats of the TYMS gene (p = 0.015). The TYMS 2R3R genotype was significantly associated with the development of OSCC (OR = 3.582; 95 % CI 1.240-10.348; p = 0.0262) and also the genotype 3R3R (OR = 3.553; 95 % CI 1.293-9.760; p = 0.0345). When analyzed together, the TYMS 2R3R + 3R3R genotypes also showed association (OR = 3.518; 95 % CI 11.188-10.348; p = 0.0177). No differences for the MTHFR C677T polymorphisms distribution were found between the oral cancer patients and controls subjects in our study (p = 0.499). Therefore, these data suggest that determination of TYMS tandem repeats could provide information on the comprehension of the risk factors and prevention of the OSCC.

Plasmatic higher levels of homocysteine in non-alcoholic fatty liver disease (NAFLD).

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is a chronic liver disease, which includes a spectrum of hepatic pathology such as simple steatosis, steatohepatitis, fibrosis and cirrhosis. The increased serum levels of homocysteine (Hcy) may be associated with hepatic fat accumulation. Genetic mutations in the folate route may only mildly impair Hcy metabolism. The aim of this study was to investigate the relation between liver steatosis with plasma homocysteine level and MTHFR C677T and A1298C polymorphisms in Brazilian patients with NAFLD. METHODS: Thirty-five patients diagnosed with NAFLD by liver biopsy and forty-five healthy controls neither age nor sex matched were genotyped for C677T and A1298C MTHFR polymorphisms using PCR-RFLP and PCR-ASA, respectively, and Hcy was determined by HPLC. All patients were negative for markers of Wilson's, hemochromatosis and autoimmune diseases. Their daily alcohol intake was less than 100 g/week. A set of metabolic and serum lipid markers were also measured at the time of liver biopsies. RESULTS: The plasma Hcy level was higher in NAFLD patients compared to the control group (p = 0.0341). No statistical difference for genotypes 677C/T (p = 0.110) and 1298A/C (p = 0.343) in patients with NAFLD and control subjects was observed. The genotypes distribution was in Hardy-Weinberg equilibrium (677C/T p = 0.694 and 1298 A/C p = 0.188). The group of patients and controls showed a statistically significant difference (p < 0.001) for BMI and HOMA_IR, similarly to HDL cholesterol levels (p < 0,006), AST, ALT, γGT, AP and triglycerides levels (p < 0.001). A negative correlation was observed between levels of vitamin B12 and Hcy concentration (p = 0.005). CONCLUSION: Our results indicate that plasma Hcy was higher in NAFLD than controls. The MTHFR C677T and A1298C polymorphisms did not differ significantly between groups, despite the 677TT homozygous frequency was higher in patients (17.14%) than in controls (677TT = 4.44%) (p > 0.05). The suggested genetic susceptibility to the MTHFR C677T and A1298C should be confirmed in large population based studies.

Influence of a TNF-α Polymorphism on the Severity of Schistosomiasis Periportal Fibrosis in the Northeast of Brazil.

AIMS: The proinflammatory cytokine tumor necrosis factor-alpha (TNF-α) is an essential component in the host immune response to infection, and it has been reported to be an important mediator in severe periportal fibrosis (PPF). We hypothesized that the (-G308A) polymorphism of the TNF-α gene is associated with the severity of PPF and that these polymorphisms influence TNF-α expression. METHODS: In this cross-sectional study, we genotyped these polymorphisms within the TNF-α gene in 256 Brazilian subjects infected with Schistosoma mansoni, with different patterns of PPF. RESULTS: The genotype (-308) AA was associated with a significant increase in the risk to advanced PPF (OR = 4.60; p = 0.009). In addition, median levels of TNF-α were higher in patients with moderate to advanced PPF, compared with mild fibrosis (20 and 17.3 pg/mL, respectively; p = 0.040). There was no association between average serum levels of TNF-α and (-G308A) TNF-α polymorphism. CONCLUSIONS: Our results suggest the (-308) AA genotype may be a risk factor for severity in advanced PPF, in this Brazilian population, and could potentially be used to predict the severity of advanced PPF in schistosomiasis.

There is no evident correlation between interleukin-10 gene polymorphisms and periportal fibrosis regression after specific treatment.

INTRODUCTION:: We evaluated the associations between interleukin-10 (IL-10) gene polymorphisms -G1082A/-C819T/-C592A and periportal fibrosis regression after specific treatment for schistosomiasis. METHODS:: This retrospective cohort study involved 125 Brazilian patients infected with Schistosomiasis mansoni, who were followed up for 2 years after specific treatment to estimate the probability of periportal fibrosis regression. RESULTS:: There was no evidence of associations between IL-10 polymorphisms and periportal fibrosis regression after treatment. CONCLUSIONS:: There was no evidence of associations between gene promoter polymorphisms of IL-10 and the regression of periportal fibrosis in this Brazilian population.

Evaluation of the cytokine mannose-binding lectin as a mediator of periportal fibrosis progression in patients with schistosomiasis.

INTRODUCTION: We hypothesized higher mannose-binding lectin level and classic factors (i.e., age, sex, alcohol consumption, exposure, and specific treatment) are associated with the severity of periportal fibrosis in schistosomiasis. METHODS: This cross-sectional study involved 79 patients infected with Schistosoma mansoni with severe or mild/moderate periportal fibrosis. Serum concentrations of mannose-binding lectin were obtained by enzyme-linked immunosorbent assay (ELISA). RESULTS: Higher serum level of mannose-binding lectin was significantly associated with advanced periportal fibrosis. CONCLUSIONS: Mannose-binding lectin may contribute to liver pathology in schistosomiasis and may represent a risk factor for advanced periportal fibrosis in the Brazilian population studied.

Association of SNP (-G1082A) IL-10 with increase in severity of periportal fibrosis in schistosomiasis, in the northeast of Brazil.

Interleukin 10 (IL-10) is an important anti-inflammatory cytokine that modulates severe periportal fibrosis (PPF). We hypothesized that genetic polymorphisms (-G1082A/-C819T/-C592A) of the IL-10 gene and classic factors (age, sex, alcohol, exposure, and specific treatment) are associated with the severity of PPF and that these polymorphisms influence IL-10 expression. In this cross-sectional study, we genotyped these polymorphisms within the IL-10 gene in 203 Brazilian subjects infected with Schistosoma mansoni, with different patterns of PPF. There was an association of protection between the ages of 41 and 60 years and advanced standard PPF. The -1082AA genotype was significantly associated with severity in PPF when compared with the -1082GG genotype. Similarly, when analyzed together, both the -1082GA+AA genotypes were significantly associated. The ACC and GTA haplotypes indicated a protective effect against PPF, while the ATA haplotype was significantly associated with PPF severity when compared with the GCC haplotype. There was no significant difference between average levels of IL-10 between clinical groups, and there was no association between average serum levels of IL-10 and (-G1082A) IL-10 polymorphism. Our results suggest that (-G1082A) IL-10 polymorphism and putative haplotypes are associated with PPF severity in the Brazilian population.

Avaliação do Polimorfismo -174 G/C do gene IL-6 na Síndrome Coronariana Aguda no Nordeste do Brasil / Evaluation of IL-6 (-174 G/C) Polymorphism in Acute Coronary Syndrome in the Northeast of Brazil

Fundamento: A síndrome coronariana aguda (SCA) é a principal causa de morbidade e mortalidade no mundo. É uma doença multifatorial causada por obstrução das artérias coronárias por placa ateromatosa que leva à isquemia cardíaca. Diversos estudos sugerem que alguns polimorfismos genéticos alteram os níveis de citocinas e influenciam o desenvolvimento de SCA. Objetivo: Neste estudo, avaliamos o polimorfismo - 174 G/C do gene IL-6 , níveis séricos de citocina e sua relação com SCA e escore de risco de thrombolysis in myocardial infarction (TIMI). Materiais e métodos: Foram selecionados 200 pacientes com SCA [risco de TIMI ­ Baixo (70), Intermediário (89), Alto (41)] na população brasileira. A genotipagem foi feita pela reação em cadeia da polimerase (PCR), seguida de sequenciamento de DNA. Resultados: Não houve diferenças significativas na distribuição dos genótipos (p = 0,53) e dos alelos (p = 0,32) entre grupos de pacientes com SCA e sem SCA no polimorfismo alélico do IL-6 , nem entre os três escores de risco TIMI (p > 0,05). Além disso, o polimorfismo do IL-6 não afetou os níveis de citocina, os quais não estavam relacionados ao escore de TIMI. Conclusões: Com esses resultados, sugerimos que o polimorfismo ­ 174 G/C do gene IL-6, até agora, não está relacionado à SCA e não alterou os níveis de citocina na população estudada. Novos estudos em populações diferentes devem ser feitos para verificar esses resultados. É importante enfatizar que, como a SCA é uma doença multifatorial, outros fatores de risco e outras citocinas pró-inflamatórias devem ser avaliadas para o conhecimento dessa patologia

Background: Acute coronary syndrome (ACS) is a leading cause of morbidity and mortality worldwide. It is a multifactorial disease caused by obstruction of the coronary arteries by atheromatous plaques and leads to heart ischemia. Several studies suggest that some genetic polymorphisms change the cytokines levels and influence ACS development. Objective: In this study, we evaluated the IL-6 polymorphism -174 G/C, serum levels of cytokine and its relationship with ACS and the thrombolysis in myocardial infarction (TIMI) risk score. Materials and Methods: A sample of 200 patients with ACS [TIMI risk ­ Low (70); Intermediate (89); High (41)] in Brazilian population was used. Genotyping was carried out by polymerase chain reaction, followed by DNA sequencing. Results: There was no significant differences in genotype (p = 0.53) and allele (p = 0.32) distributions between ACS patient and without ACS patients groups on IL-6 allelic polymorphism and between the three different TIMI risk score (p > 0.05). Moreover IL-6 polymorphism did not affect the cytokine levels and these levels were not related to the TIMI score. Conclusions: With these results, we suggest that the IL-6 (-174 G/C) polymorphism, until now, is not related to ACS and did not change the levels of the cytokine in studied population. Further studies with different populations should be done to verify those results. It is important to emphasize that, since ACS is a multifactorial disease, other risk factors and other pro-inflammatory cytokines should be assessed to better understand this pathology

There is no evident correlation between interleukin-10 gene polymorphisms and periportal fibrosis regression after specific treatment

Abstract INTRODUCTION: We evaluated the associations between interleukin-10 (IL-10) gene polymorphisms -G1082A/-C819T/-C592A and periportal fibrosis regression after specific treatment for schistosomiasis. METHODS: This retrospective cohort study involved 125 Brazilian patients infected with Schistosomiasis mansoni, who were followed up for 2 years after specific treatment to estimate the probability of periportal fibrosis regression. RESULTS: There was no evidence of associations between IL-10 polymorphisms and periportal fibrosis regression after treatment. CONCLUSIONS: There was no evidence of associations between gene promoter polymorphisms of IL-10 and the regression of periportal fibrosis in this Brazilian population.

Mutation rates at 14 STR loci in the population from Pernambuco, Northeast Brazil.

Definition about mutation rates of short tandem repeats (STRs) loci used in forensic analysis are useful for the correct interpretation of resulting genetic profiles and the definition of criterions for exclusion in paternity testing. Germline mutation of 14 STR loci was studied for 54,105 parent-child allelic transfers from 2575 paternity testing cases carried out during 2000-2007 from the Pernambuco State, Northeast Brazil. The parenthood in each of these cases was highly validated (probability > 99.99%). We identified 43 mutations at 12 loci. Locus-specific mutation rate estimates varied between 2 x 10(-4) and 2 x 10(-3), and the overall mutation rate estimate was 8 x 10(-4). Mutation events in the male germline were more frequent than in the female germline. The majority of the mutations could be explained by losses or gains of one repeat unit and there was no evidence for selection between insertion or deletion changes. Our data were compared with those of Portuguese and North-American populations for CSF1PO, D18S51, D21S11, D7S820, TH01, TPOX and demonstrated, despite the great difference in the size of the sample, that mutation rates of STR loci in a mixed population do not differ from that encountered in different populations.

13 STR loci frequencies in the population from Paraíba, Northeast Brazil.

As part of a long-term project on Northeastern Brazilians, population genetic data were obtained from 323 unrelated individuals from the state of Paraíba. The loci studied were CSF1P0, TPOX, TH01, vWA, D16S539, D7S820, D13S317, D18S51, D21S11, D8S1179, F13A01, F13B and LPL. Their distributions are in Hardy-Weinberg equilibrium. Forensic parameters were calculated and a comparison was made with geographically nearby populations.