Polymorphisms of Glutathione S-Transferase Mu 1 (GSTM1), Theta 1 (GSTT1), and Pi 1 (GSTP1) Genes and Epithelial Ovarian Cancer Risk

Background: Exposure of ovarian cells to estrogen, which is detoxified by glutathione S-transferases (GSTs), has been associated with epithelial ovarian cancer (EOC) development. Objectives: We tested in this study whether the GSTM1, GSTT1 and GSTP1 Ile105Val polymorphisms alter the risk of EOC. Materials and methods: Genomic DNA from 132 EOC patients and 132 controls was analyzed by polymerase chain reaction and restriction fragment length polymorphism methods. The differences between groups were analyzed by χ² or Fisher’s exact test. Results: The frequencies of GSTP1 Ile/Ile (57.6% versus 45.5%, P = 0.03), GSTM1 null plus GSTP1 Ile/Ile (43.5% versus 25.8%; P = 0.03) and GSTM1 null plus GSTT1 null plus GSTP1 Ile/Ile (30.3% versus 7.7%; P = 0.007) genotypes were higher in patients than in controls. Individuals with the respective genotypes had a 1.80 (95% CI: 1.06–3.06), 2.38 (95% CI: 1.08–5.24) and 11.28 (95%CI: 1.95–65.30)-fold increased risks of EOC than those with the remaining genotypes. Conclusions: Our data present preliminary evidence that GSTM1, GSTT1 and GSTP1 polymorphisms, particularly in combination, constitute important inherited EOC determinants in individuals from Southeastern Brazil.     

Downregulation of multiple stress defense mechanisms during differentiation of human embryonic stem cells

Evolutionary theory predicts that cellular maintenance, stress defense, and DNA repair mechanisms should be most active in germ line cells, including embryonic stem cells that can differentiate into germ line cells, whereas it would be energetically unfavorable to keep these up in mortal somatic cells. We tested this hypothesis by examining telomere maintenance, oxidative stress generation, and genes involved in antioxidant defense and DNA repair during spontaneous differentiation of two human embryonic stem cell lines. Telomerase activity was quickly downregulated during differentiation, probably due to deacetylation of histones H3 and H4 at the hTERT promoter and deacetylation of histone H3 at hTR promoter. Telomere length decreased accordingly. Mitochondrial superoxide production and cellular levels of reactive oxygen species increased as result of increased mitochondrial biogenesis. The expression of major antioxidant genes was downregulated despite this increased oxidative stress. DNA damage levels increased during differentiation, whereas expression of genes involved in different types of DNA repair decreased. These results confirm earlier data obtained during mouse embryonic stem cell differentiation and are in accordance with evolutionary predictions.     

Exomic variants of an elderly cohort of Brazilians in the ABraOM database

Brazilians are highly admixed with ancestry from Europe, Africa, America, and Asia and yet still underrepresented in genomic databanks. We hereby present a collection of exomic variants from 609 elderly Brazilians in a census‐based cohort (SABE609) with comprehensive phenotyping. Variants were deposited in ABraOM (Online Archive of Brazilian Mutations), a Web‐based public database. Population representative phenotype and genotype repositories are essential for variant interpretation through allele frequency filtering; since elderly individuals are less likely to harbor pathogenic mutations for early‐ and adult‐onset diseases, such variant databases are of great interest. Among the over 2.3 million variants from the present cohort, 1,282,008 were high‐confidence calls. Importantly, 207,621 variants were absent from major public databases. We found 9,791 potential loss‐of‐function variants with about 300 mutations per individual. Pathogenic variants on clinically relevant genes (ACMG) were observed in 1.15% of the individuals and were correlated with clinical phenotype. We conducted incidence estimation for prevalent recessive disorders based upon heterozygous frequency and concluded that it relies on appropriate pathogenicity assertion. These observations illustrate the relevance of collecting demographic data from diverse, poorly characterized populations. Census‐based datasets of aged individuals with comprehensive phenotyping are an invaluable resource toward the improved understanding of variant pathogenicity.     

Treatment of uncommon sites of focal primary hyperhidrosis: experience with pharmacological therapy using oxybutynin

OBJECTIVES:

Primary hyperhidrosis usually affects the hands, armpits, feet and cranio-facial region. Sweating in other areas is common in secondary hyperhidrosis (after surgery or in specific clinical conditions). Oxybutynin has provided good results and is an alternative for treating hyperhidrosis at common sites. Our aim was to evaluate the efficacy of oxybutynin as a treatment for primary sweating at uncommon sites (e.g., the back and groin).

METHODS:

This retrospective study analyzed 20 patients (10 females) who received oxybutynin for primary focal hyperhidrosis at uncommon sites. The subjects were evaluated to determine quality of life before beginning oxybutynin and six weeks afterward and they were assigned grades (on a scale from 0 to 10) to measure their improvement at each site of excessive sweating after six weeks and at the last consult.

RESULTS:

The median follow-up time with oxybutynin was 385 days (133-1526 days). The most common sites were the back (n = 7) and groin (n = 5). After six weeks, the quality of life improved in 85% of the subjects. Dry mouth was very common and was reported by 16 patients, 12 of whom reported moderate/severe dry mouth. Five patients stopped treatment (two: unbearable dry mouth, two: excessive somnolence and one: palpitations). At the last visit, 80% of patients presented with moderate/great improvement at the main sites of sweating.

CONCLUSION:

After six weeks, more than 80% of the patients presented with improvements in their overall quality of life and at the most important site of sweating. Side effects were common (80% reported at least one side effect) and caused 25% of the patients to discontinue treatment. Oxybutynin is effective for treating bothersome hyperhidrosis, even at atypical locations and most patients cope well with the side effects.     

Six weeks of aerobic training improves VO2max and MLSS but does not improve the time to fatigue at the MLSS

The purpose of this study was to investigate the effects of a 6-week aerobic training period on the time to fatigue (t _lim) during exercise performed at the maximal lactate steady state (MLSS). Thirteen untrained male subjects (TG; age 22.5 ± 2.4 years, body mass 72.9 ± 6.7 kg and VO_2max 44.9 ± 4.8 mL kg^?1 min^?1) performed a cycle ergometer test until fatigue at the MLSS power output before and after 6 weeks of aerobic training. A group of eight control subjects (CG; age 25.1 ± 2.4 years, body mass 70.1 ± 9.8 kg and VO_2max 45.2 ± 4.1 mL kg^?1 min^?1) also performed the two tests but did not train during the 6-week period. There were no differences between the groups with respect to the VO_2max or MLSS power output (MLSSw) before the treatment period. The VO_2max and the MLSSw of the TG increased by 11.2 ± 7.2 % (pre-treatment = 44.9 ± 4.8 vs. post-treatment = 49.8 ± 4.5 mL kg^?1 min^?1) and 14.7 ± 8.9 % (pre-treatment = 150 ± 27 vs. post-treatment = 171 ± 26 W), respectively, after 6 weeks of training. The results of the CG were unchanged. There were no differences in t _lim between the groups or within groups before and after training. Six weeks of aerobic training increases MLSSw and VO_2max, but it does not alter the t _lim at the MLSS.     

Human papillomavirus infection among sexual partners attending a Sexually Transmitted Disease Clinic in Rio de Janeiro, Brazil

Cervical cancer is a major source of illness and death among women worldwide and genital infection with oncogenic human papillomavirus (HPV) its principal cause. There is evidence of the influence of the male factor in the development of cervical neoplasia. Nevertheless, the pathogenic processes of HPV in men are still poorly understood. It has been observed that different HPV types can be found among couples. The objective of the present study was to investigate HPV infections in female patients (n = 60 females/group) as well as in their sexual partners and to identify the concordance of HPV genotypes among them. By using the polymerase chain reaction, we detected a 95% prevalence of HPV DNA in women with cervical intraepithelial neoplasia (CIN) compared to 18.3% in women with normal cervical epithelium, with a statistically significant difference (P < 0.001). The HPV DNA prevalence was 50% in male partners of women with CIN and 16.6% in partners of healthy women. In the control group (healthy women), only 9 couples were simultaneously infected with HPV, and only 22.2% of them had the same virus type, showing a weak agreement rate (kappa index = 0.2). Finally, we observed that HPV DNA was present in both partners in 30 couples if the women had CIN, and among them, 53.3% shared the same HPV type, showing moderate agreement, with a kappa index of 0.5. This finding supports the idea of circulation and recirculation of HPV among couples, perpetuating HPV in the sexually active population, rather than true recurrences of latent infections.     

Serine proteases of Leishmania amazonensis as immunomodulatory and disease-aggravating components of the crude LaAg vaccine

We previously demonstrated that intradermal and intramuscular vaccination with Leishmania amazonensis promastigote antigens (LaAg) increases the susceptibility of BALB/c mice to cutaneous leishmaniasis. In this study, we investigated the role played by serine and cysteine proteases as disease-promoting components of LaAg. Mice were immunized by the intramuscular route with LaAg that was pre-treated with a pool of serine or cysteine protease inhibitors (SPi and CPi, respectively) prior to infection with L. amazonensis. Neutralization of either enzyme type reversed the disease-promoting effect of LaAg, as seen by the slower lesion development. However, the parasite burden was only effectively controlled in mice receiving SPi-treated LaAg. Protection was associated with diminished production of TGF-β and particularly IL-10 in response to parasite antigens by the lesion-draining lymph node cells of vaccinated mice relative to control. In vitro, soluble proteases isolated from LaAg (LaSP-Sol) directly activated IL-4, IL-10 and TGF-β production by immune cells. Like native LaAg, vaccination with LaSP-Sol primed mice to respond to parasite challenge with a strong Jones-Mote cutaneous hypersensitivity reaction, and increased susceptibility to infection. Furthermore, neutralization of serine but not cysteine proteases blocked the capacity of LaAg to sensitize mice for Jones-Mote reaction. Together, these results indicate that soluble serine proteases are key components of LaAg responsible for its disease-promoting immunity.     

Onset of promiscuous gene expression in murine fetal thymus organ culture

T-cell differentiation and induction of tolerance to self-antigens occurs mainly in the thymus. Thymic stromal cells, specifically medullary thymic epithelial cells, express a diverse set of genes encoding parenchymal organ-specific proteins. This phenomenon has been termed promiscuous gene expression (PGE) and has been implicated in preventing organ-specific autoimmunity by inducing T-cell tolerance to self antigens. Early thymopoiesis and the critical factors involved in T-cell differentiation can be reproduced in vitro by murine fetal thymus organ culture (FTOC), which mimics the natural thymic microenvironment. To evaluate the occurrence of PGE in FTOC, gene expression profiling during in vitro thymic development in BALB/c mice was performed using a set of nylon cDNA microarrays containing 9216 sequences. The statistical analysis of the microarray data (sam program) revealed the temporal repression and induction of 57 parenchymal and seven lymphoid organ-specific genes. Most of the genes analysed are repressed during early thymic development (15-17 days post-coitum). The expression of the autoimmune regulator (AIRE) gene at 16 days post-coitum marks the onset of PGE. This precedes the induction of parenchymal organ genes during the late developmental phase at 20 days post-coitum. The mechanism of T-cell tolerance induction begins during fetal development and continues into adulthood. Our findings are significant because they show a fine demarcation of PGE onset, which plays a central role in induction of T-cell tolerance.     

Bariatric surgery and the gut-brain communication—The state of the art three years later

ObjectiveThis review analyzes the literature concerning gut peptides and bariatric surgery, from 2005 to July 2009. In particular, we are interested in whether, and how, gastrointestinal peptide alterations following surgery interfere with appetite/satiety, and what role they might play in the resolution of comorbidities.Research methods and procedurePubMed/MEDLINE and ISI Web of Knowledge were used to search for human studies concerning gut peptides profiles after any bariatric operation technique.ResultsMost of the studies reviewed had longitudinal design, short follow-up, and low statistical power. The diversity of study results may be partially explained by methodological aspects. Glucagon-like peptide-1, gastric inhibitory peptide, and peptide YY alterations may contribute to the excellent results in glycemic control of diabetics. Results do vary depending on bariatric operation technique; this is particularly evident in the case of ghrelin, which has been much studied in recent years. Ghrelin suppression has been linked to increased satiety, alterations in energy homeostasis, and better glucose metabolism.ConclusionsThere is a lack of long-term data on gastrointestinal hormone profiles after bariatric surgery and the studies have many methodological pitfalls. We still need prospective, long-term, good methodological studies in this area.     

Hybridization signatures of gamma-irradiated murine fetal thymus organ culture (FTOC) reveal modulation of genes associated with T-cell receptor V(D)J recombination and DNA repair

In this study, we observed the occurrence of TRBV8.1-DB2.1 V(D)J recombination in murine fetal thymus organ culture (FTOC), in which the thymic microenvironment is mimicked. Since ionizing radiation affects T-cell development, we irradiated FTOCs with gamma rays to evaluate the modulation of genes implicated in TRBV8.1-BD2.1 rearrangements. The nylon cDNA microarray method was employed to monitor the expression of 9216 genes, which were organized in coexpression clusters. Clustering analysis showed similar expression profiling of genes implicated in the V(D)J recombination and DNA double strand break (DSB) repair processes such as XRCC4, RAG-2, Artemis and DNA-PK-cs, thus suggesting overlap between the two processes. The RUNX3 gene, whose coded protein binds to the enhancers of TR genes, was also modulated and the DNA cross-linking LR1 gene, which plays a role in the opening of hairpin DNA structures and whose expression pattern is similar to Artemis, may play a role in the control of V(D)J recombination. Furthermore, our data demonstrate that the FTOC model system and cDNA microarray method are useful tools to evidentiate genes that may play a role in both processes V(D)J recombination and DNA repair.