Estrogen receptor 1 gene polymorphisms and coronary artery disease in the Brazilian population

We examined the association of three established single nucleotide polymorphisms, IVS1-397T>C, IVS1-351A>G, and +261G>C, in the ESR1 gene with the prevalence and severity of coronary atherosclerosis in a southern Brazilian population of European ancestry. Three hundred and forty-one subjects (127 women and 214 men) with coronary artery disease (CAD) were classified as having significant disease (CAD+ patient group) when they showed 60% or more luminal stenosis in at least one coronary artery or major branch segment at angiography; patients with 10% or less luminal stenosis were considered to have minimal CAD (CAD- patient group). The control sample consisted of 142 subjects (79 women and 63 men) without significant disease, in whom coronary angiography to rule out the presence of asymptomatic CAD was not performed. The polymorphisms were investigated by polymerase chain reaction followed by restriction analyses. In the male sample, the +261G>C*C allele was more frequent in CAD+ than CAD- subjects (8 versus 1%, P = 0.024). Homozygosity for the C allele of the IVS1-397T>C polymorphism was also significantly associated with increased CAD severity (OR: 2.99; 95% CI = 1.35-6.63; P = 0.007). In agreement with previous findings, these results suggest that the IVS1-397T>C*C allele was associated with CAD severity independent of gender, whereas the association of the +261G>C variant with CAD was observed in males only. The relation between ESR1 variation and CAD may influence clinical decisions such as the use of hormone therapy, and additionally will be helpful to identify the genetic susceptibility determinants of cardiovascular disease development.

Hyperhomocystinemia in patients with coronary artery disease

Hyperhomocystinemia has been related to an increased risk of cardiovascular disease in several studies. The C677T polymorphism for the gene that encodes the methylenetetrahydrofolate reductase enzyme (MTHFR) and low plasma folate levels are common causes of hyperhomocystinemia. Due to differences in nutritional patterns and genetic background among different countries, we evaluated the role of hyperhomocystinemia as a coronary artery disease (CAD) risk factor in a Brazilian population. The relation between homocysteine (Hcy) and the extent of CAD, measured by an angiographic score, was determined. A total of 236 patients referred for coronary angiography for clinical reasons were included. CAD was found in 148 (62.7%) patients and 88 subjects had normal or near normal arteries. Patients with CAD had higher Hcy levels [mean (SD)] than those without disease (14 (6.8) vs 12.5 (4.0) µM; P = 0.04). Hyperhomocystinemia (Hcy >17.8 µM) prevalence was higher in the CAD group: 31.1 vs 12.2% (P = 0.01). After adjustment for major risk factors, we found an independent association between hyperhomocystinemia and CAD (OR = 2.48; 95% CI = 1.02-6.14). Patients with a more advanced coronary score had a higher frequency of hyperhomocystinemia and tended to have higher mean Hcy levels. An inverse relation between plasma folate and Hcy levels was found (r = -0.14; P = 0.04). Individuals with the MTHFR C677T polymorphism had a higher prevalence of hyperhomocystinemia than those without the mutated allele. We conclude that hyperhomocystinemia is independently associated with CAD, with a positive association between Hcy level and disease severity.

Risk factors associated with the death of patients hospitalized for juvenile systemic lupus erythematosus

We assessed the risk factors associated with death in patients hospitalized for juvenile systemic lupus erythematosus (JSLE) and evaluated the autopsy reports. A total of 57,159 hospitalizations occurred in our institution from 1994 to 2003, 169 of them involving 71 patients with JSLE. The most recent hospitalization of these patients was evaluated. Patients were divided into two groups based on mortality during hospitalization: those who survived (N = 53) and those who died (N = 18). The main causes of hospitalization were JSLE activity associated with infection in 52% and isolated JSLE activity in 44%. Univariate analysis showed that a greater risk of death was due to severe sepsis (OR = 17.8, CI = 4.5-70.9), systemic lupus erythematosus disease activity index (SLEDAI) ³8 (OR = 7.6, CI = 1.1-53.8), general infections (OR = 6.1, CI = 1.5-25), fungal infections (OR = 5.4, CI = 3.2-9), acute renal failure (OR = 5.1, CI = 2.5-10.4), acute thrombocytopenia (OR = 3.9, CI = 1.9-8.4), and bacterial infections (OR = 2.3, CI = 1.2-7.5). Stratified analysis showed that severe sepsis and SLEDAI ³8 were not confounder variables. In the multivariate analysis, logistic regression showed that the only independent variable in death prediction was severe sepsis (OR = 98, CI = 16.3-586.2). Discordance between clinical diagnosis and autopsy was observed in 6/10 cases. Mortality of hospitalized JSLE patients was associated with severe sepsis. Autopsy was important to determine events not detected or doubtful in dead patients and should always be requested.

Baicalin reduces the severity of experimental autoimmune encephalomyelitis

Scutellaria baicalensis Georgi is one of the important medicinal herbs widely used for the treatment of various inflammatory diseases in Asia. Baicalin (BA) is a bioactive anti-inflammatory flavone found abundantly in Scutellaria baicalensis Georgi. To explore the therapeutic potential of BA, we examined the effects of systemic administration of the flavone (5 and 10 mg/kg, ip) on relapsing/remitting experimental autoimmune encephalomyelitis (EAE) induced by proteolipid protein 139-151 in SJL/J mice, an experimental model of multiple sclerosis. The mice treated with PBS or BA at day -1 and for 3 consecutive days were observed daily for clinical signs of disease up to 60 days after immunization. In the PBS-EAE group, neurological scores were: incidence (100%), mean day of onset (8.0 ± 0.73), peak clinical score (3.0 ± 0.4), and cumulative disease index (141.8 ± 19.4). In the BA-EAE group (5 or 10 mg kg-1 day-1, respectively), incidence (95 or 90%), mean day of onset (9.0 ± 0.80 or 9.2 ± 0.75; P = 0.000), peak clinical score (2.2 ± 0.3 or 2.0 ± 0.3; P = 0.000), and cumulative disease index (75.9 ± 10.1 or 62.9 ± 8.4; P = 0.000) decreased, accompanied by the histopathological findings (decrease of dense mononuclear infiltration surrounding vascellum) for the spinal cord. Additionally, the in vitro effects of BA (5, 10, and 25 µM) on mononuclear cells collected from popliteal and inguinal lymph nodes of day-10 EAE mice were evaluated using an MTT reduction assay for cell proliferation, and ELISA to measure IFN-g and IL-4 cytokines. Compared with the control group, BA caused an increase in IL-4 (EAE-DMSO: 3.56 ± 0.42 pg/mL vs EAE-BA (5, 10, and 25 µM): 6.03 ± 1.1, 7.83 ± 0.65, 10.54 ± 1.13 pg/mL, respectively; P < 0.001); but inhibited IFN-g (EAE-DMSO: 485.76 ± 25.13 pg/mL vs EAE-BA (5, 10, and 25 µM): 87.08 ± 9.24, 36.27 ± 5.44, 19.18 ± 2.93 pg/mL, respectively; P < 0.001) and the proliferation of mononuclear cells (EAE-DMSO: 0.73 ± 0.021 vs EAE-BA (5, 10, and 25 µM): 0.41 ± 0.015, 0.31 ± 0.018, 0.21 ± 0.11, respectively; P < 0.001) in a concentration-dependent manner. The results suggest that BA might be effective in the treatment of multiple sclerosis.

Do socioeconomic factors explain why maternal smoking during pregnancy is more frequent in a more developed city of Brazil?

The prevalence of smoking during pregnancy in Ribeirão Preto, a rich Brazilian city, was significantly higher (21.4%) than in São Luís (5.9%), a less developed city. To assess which variables explain the difference in prevalence of smoking during pregnancy, data from two birth cohorts were used, including 2846 puerperae from Ribeirão Preto, in 1994, and 2443 puerperae from São Luís, in 1997/98. In multivariable analysis, risk of maternal smoking during pregnancy was higher in São Luís for mothers living in a household with five or more persons (OR = 1.72, 95%CI = 1.12-2.64), aged 35 years or older (OR = 1.98, 95%CI = 0.99-3.96), who had five or more children (OR = 2.10, 95%CI = 1.16-3.81), and whose companion smoked (OR = 2.20, 95%CI = 1.52-3.18). Age of less than 20 years was a protective factor (OR = 0.55, 95%CI = 0.33-0.92). In Ribeirão Preto there was association with maternal low educational level (OR = 2.18, 95%CI = 1.30-3.65) and with a smoking companion (OR = 3.25, 95%CI = 2.52-4.18). Receiving prenatal care was a protective factor (OR = 0.24, 95%CI = 0.11-0.49). Mothers from Ribeirão Preto who worked outside the home were at a higher risk and those aged 35 years or older or who attended five or more prenatal care visits were at lower risk of smoking during pregnancy as compared to mothers from São Luís. Smoking by the companion reduced the difference between smoking rates in the two cities by 10%. The socioeconomic variables in the model did not explain the higher prevalence of smoking during pregnancy in the more developed city.

Is there an association between T102C polymorphism of the serotonin receptor 2A gene and urinary incontinence?

The regulation of bladder function is influenced by central serotonergic modulation. Several genetic polymorphisms related to serotonin control have been described in the literature. T102C polymorphism of the serotonin receptor 2A gene (5-HT2A) has been shown to be associated with certain diseases such as non-fatal acute myocardial infarction, essential hypertension, and alcoholism. In the present study, we examined the association between 5-HT2A gene polymorphism and urinary incontinence in the elderly. A case-control study was performed in 298 elderly community dwellers enrolled in the Gravataí-GENESIS Project, Brazil, which studies gene-environmental interactions in aging and age-related diseases. Clinical, physical, biochemical, and molecular analyses were performed on volunteers. 5-HT2A genotyping was determined by PCR-RFLP techniques using the HpaII restriction enzyme. The subjects had a mean age of 68.05 ± 6.35 years (60-100 years), with 16.9% males and 83.1% females. The C allele frequency was 0.494 and the T allele frequency was 0.506. The CC genotype frequency was 21.78%, the CT genotype frequency was 55.24% and the TT genotype frequency was 22.98%. We found an independent significant association between the TT genotype (35.7%) and urinary incontinence (OR = 2.06, 95%CI = 1.16-3.65). Additionally, urinary incontinence was associated with functional dependence and systolic hypertension. The results suggest a possible genetic influence on urinary incontinence involving the serotonergic pathway. Further investigations including urodynamic evaluation will be performed to better explain our findings.

Are birth weight and maternal smoking during pregnancy associated with malnutrition and excess weight among school age children?

In the late 1980's child malnutrition was still prevalent in Brazil, and child obesity was beginning to rise in the richest regions of the country. To assess the extent of the nutritional transition during the period and the influence of birth weight and maternal smoking on the nutritional condition of schoolchildren, we estimated the prevalence of excess weight and malnutrition in a cohort of Brazilian schoolchildren from 1987 to 1989. We calculated the body mass index (BMI) of 8- to 10-year-old schoolchildren born in Ribeirão Preto in 1978/79. We considered children with a BMI <5th percentile (P5) to be malnourished, children with P5³BMIormal, and children with BMI ³P85 to be overweight. We evaluated the association of these nutritional disorders with birth factors (infant weight, sex, preterm delivery, number of pregnancies, maternal smoking during pregnancy, marital status, and schooling) and type of school using nominal logistic regression. A total of 2797 schoolchildren were evaluated. There was a significant prevalence of malnutrition (9.5%) and excess weight already tended to increase (15.7%), while 6.4% of the children were obese. Excess weight was more prevalent among children attending private schools (odds ratio, OR = 2.27) and firstborn children (OR = 1.69). Maternal smoking during pregnancy protected against malnutrition (OR = 0.56), while children with lower birth weight were at higher risk for malnutrition (OR = 4.23). We conclude that a nutritional transition was under way while malnutrition was still present, but excess weight and related factors were already emerging.

Effects of sedation during upper gastrointestinal endoscopy on endocrine response and cardiorespiratory function

Upper gastrointestinal endoscopy is often accompanied by tachycardia which is known to be an important pathogenic factor in the development of myocardial ischemia. The pathogenesis of tachycardia is unknown but the condition is thought to be due to the endocrine response to endoscopy. The purpose of the present study was to investigate the effects of sedation on the endocrine response and cardiorespiratory function. Forty patients scheduled for diagnostic upper gastrointestinal endoscopy were randomized into 2 groups. While the patients in the first group did not receive sedation during upper gastrointestinal endoscopy, the patients in the second group were sedated with intravenous midazolam at the dose of 5 mg for those under 65 years or 2.5 mg for those aged 65 years or more. Midazolam was administered by slow infusion. In both groups, blood pressure, ECG tracing, heart rate, and peripheral oxygen saturation (SpO2) were monitored during endoscopy. In addition, blood samples for the determination of cortisol, glucose and C-reactive protein levels were obtained from patients in both groups prior to and following endoscopy. Heart rate and systolic arterial pressure changes were within normal limits in both groups. Comparison of the two groups regarding the values of these two parameters did not reveal a significant difference, while a statistically significant reduction in SpO2 was found in the sedation group. No significant differences in serum cortisol, glucose or C-reactive protein levels were observed between the sedated and non-sedated group. Sedation with midazolam did not reduce the endocrine response and the tachycardia developing during upper gastrointestinal endoscopy, but increased the reduction in SpO2.

Apolipoprotein E polymorphism in Brazilian dyslipidemic individuals: Ouro Preto study

The influence of apolipoprotein E alleles and genotypes on plasma lipid levels was determined in 185 individuals of mixed ethnicity living in Ouro Preto, Brazil. DNA was obtained from blood samples and the genotypes were determined by an RFLP-PCR procedure. The *3 allele was the most frequent (72%), followed by *4 (20%) and *2 (8%); *4 frequency was higher and *2 frequency was lower in the dyslipidemic group than in the normal control group. The *2 carriers presented lower LDL and total cholesterol levels compared to the *3 and *4 carriers. All six expected genotypes were observed in the individuals genotyped: E2/2 (2.1%), E4/4 (2.7%), E2/4 (3.7%), E2/3 (8.0%), E3/3 (53.3%), E3/4 (29.9%); no difference in genotype frequencies was found between the normal and dyslipidemic groups. Compared with *2, the presence of *3 increases more than two times the risk for dyslipidemia (OR = 2.31; P = 0.025; 95% CI = 1.06-5.06) and the presence of *4 increases it three times (OR = 3.31; P = 0.006; 95% CI = 1.36-8.04). The only significant effect of genotype was an increased risk for dyslipidemia in the *4 genotype carriers (E3/4 + E4/4) compared with the *2 genotype carriers (E2/2 + E2/3) with OR = 3.69 (95% CI = 1.25-10.88). The present study indicates that in the Ouro Preto admixed population the presence of APOE *2 can confer a protective effect, whereas the presence of APOE *4 implies an enhanced risk for dyslipidemia.

Acute leukemia in early childhood

Acute leukemia in early childhood is biologically and clinically distinct. The particular characteristics of this malignancy diagnosed during the first months of life have provided remarkable insights into the etiology of the disease. The pro-B, CD10 negative immunophenotype is typically found in infant acute leukemia, and the most common genetic alterations are the rearrangements of the MLL gene. In addition, the TEL/AML1 fusion gene is most frequently found in children older than 24 months. A molecular study on a Brazilian cohort (age range 0-23 months) has detected TEL/AML1+ve (N = 9), E2A/PBX1+ve (N = 4), PML/RARA+ve (N = 4), and AML1/ETO+ve (N = 2) cases. Undoubtedly, the great majority of genetic events occurring in these patients arise prenatally. The environmental exposure to damaging agents that give rise to genetic changes prenatally may be accurately determined in infants since the window of exposure is limited and known. Several studies have shown maternal exposures that may give rise to leukemogenic changes. The Brazilian Collaborative Study Group of Infant Acute Leukemia has found that mothers exposed to dipyrone, pesticides and hormones had an increased chance to give birth to babies with infant acute leukemia [OR = 1.48 (95%CI = 1.05-2.07), OR = 2.27 (95%CI = 1.56-3.31) and OR = 9.08 (95%CI = 2.95-27.96)], respectively. This review aims to summarize recent clues that have facilitated the elucidation of the biology of early childhood leukemias, with emphasis on infant acute leukemia in the Brazilian population.

A majority of Brazilian patients with rheumatoid arthritis HLA-DRB1 alleles carry both the HLA-DRB1 shared epitope and anti-citrunillated peptide antibodies

The objective of the present study was to evaluate the contribution of the shared epitope (SE), the rheumatoid arthritis (RA) protection model, and the occurrence of anti-cyclic citrullinated peptide (anti-CCP) antibodies in RA patients from a genetically diverse population. One hundred and forty Brazilian RA patients and 161 matched controls were typed for HLA-DRB1 alleles using amplified DNA hybridized with sequence-specific oligonucleotide probes or primers. Patients were stratified according to the presence or absence of SE (DRB1*0401, *0404, *0405, *0101, *1001, and *1402), of the DERAA alleles (DRB1*0103, *0402, *1102, *1103, *1301, *1302, and *1304), and X (all other alleles). Anti-CCP antibodies were measured by ELISA. The combined frequency of SE-positive alleles was significantly greater (76.4 vs 23.6%, P < 0.0001) than the controls. The SE/SE and SE/X genotypes were over-represented (P < 0.0001, OR = 6.02) and DERAA/X was under-represented in RA patients (P < 0.001, OR = 0.49), whereas the frequencies of the SE/DERAA, X/X and X/DERAA genotypes were not significantly different from controls. The frequency of anti-CCP antibodies was higher in SE-positive patients than in SE-negative patients (64.6 vs 44.7%, P = 0.03; OR = 2.25). Although the Brazilian population is highly miscegenated, the results of this study support the findings observed in most genetically homogeneous populations with RA; however, they are not mutually exclusive but rather complementary. The participation of DRB1-DERAA alleles in protection against RA was also observed (OR = 0.4; 95%CI = 0.23-0.68).

Diabetic retinopathy is associated with early autonomic dysfunction assessed by exercise-related heart rate changes

Diabetic retinopathy has been associated with cardiac autonomic dysfunction in both type 1 and type 2 diabetes mellitus (DM) patients. Heart rate (HR) changes during exercise testing indicate early alterations in autonomous tonus. The aim of the present study was to investigate the association of diabetic retinopathy with exercise-related HR changes. A cross-sectional study was performed on 72 type 2 and 40 type 1 DM patients. Autonomic dysfunction was assessed by exercise-related HR changes (Bruce protocol). The maximum HR increase, defined as the difference between the peak exercise rate and the resting rate at baseline, and HR recovery, defined as the reduction in HR from the peak exercise to the HR at 1, 2, and 4 min after the cessation of the exercise, were determined. In type 2 DM patients, lower maximum HR increase (OR = 1.62, 95%CI = 1.03-2.54; P = 0.036), lower HR recovery at 2 (OR = 2.04, 95%CI = 1.16-3.57; P = 0.012) and 4 min (OR = 2.67, 95%CI = 1.37-5.20; P = 0.004) were associated with diabetic retinopathy, adjusted for confounding factors. In type 1 DM, the absence of an increase in HR at intervals of 10 bpm each during exercise added 100% to the odds for diabetic retinopathy (OR = 2.01, 95%CI = 1.1-3.69; P = 0.02) when adjusted for DM duration, A1c test and diastolic blood pressure. In conclusion, early autonomic dysfunction was associated with diabetic retinopathy. The recognition of HR changes during exercise can be used to identify a high-risk group for diabetic retinopathy.

Streptozotocin-induced mechanical hypernociception is not dependent on hyperglycemia

Since streptozotocin (STZ)-induced diabetes is a widely used model of painful diabetic neuropathy, the aim of the present study was to design a rational protocol to investigate whether the development of mechanical hypernociception induced by STZ depends exclusively on hyperglycemia. Male Wistar rats (180-200 g; N = 6-7 per group) received a single intravenous injection of STZ at three different doses (10, 20, or 40 mg/kg). Only the higher dose (40 mg/kg) induced a significant increase in blood glucose levels, glucose tolerance and deficiency in weight gain. However, all STZ-treated rats (hyperglycemic or not) developed persistent (for at least 20 days) and indistinguishable bilateral mechanical hypernociception that was not prevented by daily insulin treatment (2 IU twice a day, sc). Systemic morphine (2 mg/kg) but not local (intraplantar) morphine treatment (8 µg/paw) significantly inhibited the mechanical hypernociception induced by STZ (10 or 40 mg/kg). In addition, intraplantar injection of STZ at doses that did not cause hyperglycemia (30, 100 or 300 µg/paw) induced ipsilateral mechanical hypernociception for at least 8 h that was inhibited by local and systemic morphine treatment (8 µg/paw or 2 mg/kg, respectively), but not by dexamethasone (1 mg/kg, sc). The results of this study demonstrate that systemic administration of STZ induces mechanical hypernociception that does not depend on hyperglycemia and intraplantar STZ induces mechanical sensitization of primary sensory neurons responsive to local morphine treatment.

Coronary artery calcification is associated with insulin resistance index in patients with type 1 diabetes

The objective of the present study was to evaluate the risk factors associated with the presence of coronary artery calcification (CAC) in patients with type 1 diabetes (T1D). A cross-sectional study was conducted on 100 consecutive T1D patients without coronary artery disease, with at least 5 years of diabetes and absence of end-stage renal disease. Mean age was 38 ± 10 years and 57% were males. CAC score was measured by multidetector computed tomography (Siemens Sensation 64 Cardiac). The insulin resistance index was measured using the estimated glucose disposal rate (eGDR). The eGDR was lower among CAC-positive patients than among CAC-negative patients, suggesting an increased insulin resistance. In a logistic regression model adjusted for age (at 10-year intervals), eGDR, diabetic nephropathy and gender, CAC was associated with age [OR = 2.73 (95%CI = 1.53-4.86), P = 0.001] and with eGDR [OR = 0.08 (95%CI = 0.02-0.21), P = 0.004]. In T1D subjects, insulin resistance is one of the most important risk factors for subclinical atherosclerosis.