Estrogen receptor alpha gene ( ESR1) polymorphism can contribute to clinical findings in systemic lupus erythematosus patients.

Background Estrogens have a modulatory effect on several immune responses, many of which are correlated to autoimmune diseases. Estrogens act through binding to their receptors, and an overexpression of these receptors has been identified in patients with different autoimmune diseases. Here we analyzed the association of a putative functional genetic variant in the main estrogen receptor (ERα) gene ( ESR1), and the susceptibility to clinical findings and severity of SLE. Methods A total of 426 individuals (266 healthy controls and 160 SLE patients) were genotyped for the polymorphism rs2234693 in the ESR1 gene. Allele and genotype frequencies were calculated and analyzed between cases and controls using Unphased software. Results The SNP rs2234693 was not associated with SLE per se but the minor allele rs2234693-C was correlated with the presence of nephritis and discoid skin rash. On the other hand, the rs2234693-CC genotype was correlated with the absence of arthritis as well as anti-ANA and anti-RNP autoantibodies. The comprehensive clinical analysis of these patients revealed a more severe status of the disease, characterized by a younger age of onset and higher number of organs involved when compared to European populations. Conclusions Minor allele rs2234693-C was associated with renal and cutaneous involvement, as well as the absence of arthritis, anti-ANA and anti-RNP autoantibodies.

Functional polymorphisms of interleukin-18 gene and risk of breast cancer in a Brazilian population.

Interleukin-18 (IL-18) is a key cytokine responsible for immune response and involved in the process of cancer development. In this case-control study, we tested whether IL-18 promoter polymorphism contributes to breast cancer susceptibility in Brazilian patients. The two groups studied were 154 patients with breast cancer and 118 healthy individuals. The frequency of IL-18 promoter single nucleotide polymorphisms (SNPs) at positions -607 (C/A) (rs1946518) and -137 (G/C) (rs187238) was determined by polymerase chain reaction analyses. The polymorphisms genotyped in this study showed a significant association with breast cancer under different genetic models. Both SNPs showed a positive association. For the IL18-607 polymorphism the best model was the codominant genetic model [CC vs AA, P = 0.004, odds ratio (OR) = 2.782, 95% confidence interval (CI) 1.385-5.589]. For IL18-137 statistical significance was found using the recessive genetic model (P = 0.008, OR = 3.896, 95% CI 1.427-10.639). The association between the haplotypes of the IL18 gene and breast cancer was further confirmed. Our results suggest that IL18-607 and IL18-137 polymorphism contributes to increase the breast cancer risk. To our knowledge, this is the first report regarding Brazilian breast cancer patients and IL18 promoter polymorphisms.

Diversity of the MBL2 gene in various Brazilian populations and the case of selection at the mannose-binding lectin locus.

The mannose binding lectin (MBL2) polymorphism is responsible for a common immunodeficiency in the human species. There were suggestions that the MBL2 polymorphism has been under balancing selection, based on the high global frequency of alleles generating MBL deficiency and on the worldwide distribution of diseases negatively associated with them. To describe the distribution of MBL2 allelic haplotypes in Brazilian populations and to discuss the evolution of this polymorphism, we analyzed six South Brazilian populations (152 Guarani Amerindian, 239 Kaingang Amerindian, 107 admixed, Brazilian 32 Afro-Brazilian, 202 Euro-Brazilian and 16 Oriental-Brazilian). Eight haplotypes were observed: MBL2*HYPA, LYQA, LYPA, LXPA, LYPB, LYQC, HYPD, and LYPD. In addition, through sequencing of the promoter and exon 1 from Amerindian and Oriental individuals, three new single-nucleotide polymorphisms (SNPs) were found in the MBL2 promoter region in the Kaingang. Analysis of the sequencing data by neutrality tests (Tajima's D and Fu and Li's D* and F*) revealed no deviation from selective neutrality equilibrium in the Guarani and Kaingang. Significant Fay and Wu's H results are explained by the recent gene flow in these populations. Contrarily to previous thoughts, stochastic evolutionary factors seem therefore to have had a predominant role in shaping the MBL2 polymorphism, at least in the Amerindians.

Gibberellic acid and dwarfism effects on the growth dynamics of B73 maize (Zea mays L.) leaf blades: a transient increase in apoplastic peroxidase activity precedes cessation of cell elongation.

The relationship between apoplastic peroxidase (EC 1.11.1.7) activity and cessation of growth in maize (Zea mays L.) leaf blades was investigated by altering elongation zone length. Apoplastic peroxidase activity in the elongation and secondary cell wall deposition zones of elongating leaf blades of the maize inbred line B73 was used as a control and compared to leaves of the dwarf mutant D8-81127, a near-isogenic line of B73 unresponsive to gibberellins, and to leaves of B73 plants to which gibberellic acid (GA(3)) had been applied via root uptake. Elongation zone length was increased by treatment with GA(3) through an increase in cell number as well as increased final cell length. The shorter elongation zone of dwarf leaves occurred primarily through reduced final cell length. Although elongation zone length differed among dwarf, control, and GA(3)-treated leaf blades, in all three treatments a transient increase in apoplastic peroxidase activity preceded a reduction in the segmental elongation rate in leaves. A peroxidase isoenzyme with pI 7.0 occurred in the leaf elongation zone during growth deceleration in all three treatments, and its activity decreased as growth displaced tissue into the region of secondary cell wall deposition. Growth cessation for all treatments coincided with the first appearance of peroxidase isozymes with pIs of 5.6 and 5.7. Based on the activity of particular isozymes relative to growth and differentiation, the pI 7.0 isoenzyme is most likely to be involved in cessation of cell elongation, while isozymes with pIs 5.6 and 5.7 are likely to be active in lignification.

Influence of temperature and humidity on laser in situ keratomileusis outcomes.

PURPOSE: The influence of ambient factors on the results of refractive surgery is not well-known. This study evaluated the influence of temperature and humidity on laser in situ keratomileusis (LASIK) outcomes. METHODS: Two hundred thirty-seven patients who underwent LASIK at the Clivan Instituto de Oftalmologia in Salvador--Bahia--Brazil, between May 1999 and March 2000, were evaluated. A total of 156 (65.8%) patients were female. Mean age was 30.3 +/- 7.6 years. Refractive errors: 197 patients (83.12%) had compound myopic astigmatism, 17 patients (7.17%) had myopia, 11 patients (4.64%) had compound hyperopic astigmatism, and 12 patients (5.07%) had other. Results at 15 and 60 days after LASIK were compared according to different levels of temperature and humidity in the operating room during the procedure. RESULTS: Patients whose spherical equivalent refraction varied between -0.50 to +0.50 D at 15 days after LASIK had surgery performed when the temperature was 25.1 +/- 1.4 degrees C and humidity was 45.1 +/- 4.2%; for the others, temperature was 24.7 +/- 1.5 degrees C (P = .12) and humidity was 43.0 +/- 4.0% (P = .002). The linear regression coefficient showed that lower temperature levels were associated with lower spherical equivalent refractions at 60 days after LASIK (r2 = .14; P = .03) but not at 15 days after LASIK (P = .98). The evaluation of humidity indicated an influence at 15 days after LASIK (r2 = .44; P = .04), as well as at 60 days (r2 = .45; P = .0002). CONCLUSION: Operating room environment may influence LASIK outcomes; humidity may be more significant than temperature.