Oxidative DNA damage induced by S(IV) in the presence of Cu(II) and Cu(I) complexes

The DNA damage induced by S(IV) in the presence of some Cu(II) complexes in air saturated solution was investigated. The addition of S(IV) to an air saturated solution containing CuII GGA (GGA = glycylglycyl-L-alanine), CuII G3 (G3 = triglycine) or CuII G4 (G4 = tetraglycine) and Ni(II) traces, causes rapid formation of the respective Cu(III) complex, with simultaneous O2 uptake and S(IV) oxidation. SO3•- and HO• were detected by EPR-spin trapping experiments. The DNA strand breaks were attributed to the oxysulfur radicals formed. In the reduction of Cu(II)/BCA (BCA = 4,4' dicarboxy-2-2'-biquinoline) by S(IV), with CuI BCA complex formation, there is the possible formation of carbon centered radical of BCA or peroxyl radical (ROO•) capable of oxidizing DNA bases. The intensity of DNA damage in the presence of these Cu(II) complexes and S(IV) (10-300 µmol L-1) followed the order: CuII BCA ∼ CuII G4 ∼ Cu(II) (added as Cu(NO3)2) > CuII G3 ∼ CuII GGA. Specifically for CuII BCA the damage occurred even at lower S(IV) concentration (0.1 µmol L-1). For the Cu(II) complexes with glycylglycylhistidine, glycylhistidylglycine, glycylhistidyllysine and glycylglycyltyrosylarginine the Cu(III) formation and the DNA damage was not observed.

Thermal behavior and decomposition kinetics of rifampicin polymorphs under isothermal and non-isothermal conditions

The thermal behavior of two polymorphic forms of rifampicin was studied by DSC and TG/DTG. The thermoanalytical results clearly showed the differences between the two crystalline forms. Polymorph I was the most thermally stable form, the DSC curve showed no fusion for this species and the thermal decomposition process occurred around 245 ºC. The DSC curve of polymorph II showed two consecutive events, an endothermic event (Tpeak = 193.9 ºC) and one exothermic event (Tpeak = 209.4 ºC), due to a melting process followed by recrystallization, which was attributed to the conversion of form II to form I. Isothermal and non-isothermal thermogravimetric methods were used to determine the kinetic parameters of the thermal decomposition process. For non-isothermal experiments, the activation energy (Ea) was derived from the plot of Log β vs 1/T, yielding values for polymorph form I and II of 154 and 123 kJ mol-1, respectively. In the isothermal experiments, the Ea was obtained from the plot of lnt vs 1/T at a constant conversion level. The mean values found for form I and form II were 137 and 144 kJ mol-1, respectively.

Insetos em presépios e as "formigas vestidas" de Jules Martin (1832-1906): uma curiosa manufatura paulistana do final do século XIX

Encontrados no Brasil desde os primórdios da colonização portuguesa, os presépios logo tiveram de adaptar-se à realidade local, circunstância muito propícia ao aparecimento de concepções heterodoxas e ao emprego de elementos exóticos da fauna e flora de cada região. Como registros envolvendo insetos são muito pouco comuns, chama a atenção que fêmeas de saúva, Atta sp. (Hymenoptera, Formicidae), tenham sido aproveitadas na composição de presépios no estado de São Paulo. Tendo subsistido pelo menos até a década 1960, os "presépios de formigas" existentes em cidades como Embu das Artes poderiam estar relacionados às "formigas vestidas" criadas por Jules Martin, curiosa manufatura paulistana do último quartel do século XIX.

Contribuição para o estudo dos Rhinotragini (Coleoptera, Cerambycidae): I. mudança de status nos subgêneros de Ommata white, 1855 e revisão de Agaone Pascoe, 1859

Todos os subgêneros de Ommata são elevados a gênero, levando-se em consideração a diversidade de caracteres encontrados em cada um deles. Agaone é revisto e uma nova espécie é descrita do Brasil (Minas Gerais, Espírito Santo, Rio de Janeiro): A. punctilla sp. nov. Cantharoxylymna Linsley, 1934 é considerado sinônimo junior de Agaone. Grupiara gen. nov. é descrito para alocar Ommata (Agaone) viridis Gounelle, 1911.

Estudo randômico da correção cirúrgica do prolapso uterino através de tela sintética de polipropileno tipo I comparando histerectomia versus preservação uterina

OBJETIVO: Comparar os resultados anatômicos pós-operatórios de pacientes portadoras de prolapso uterino tratadas utilizando tela de polipropileno para correção dos defeitos do assoalho pélvico, comparando histerectomia vaginal com a preservação do útero. MÉTODO: Estudo randomizado com 31 mulheres portadoras de prolapso uterino estádio III ou IV (POP-Q) divididas em dois grupos: Grupo HV- 15 mulheres submetidas à histerectomia vaginal e reconstrução da anatomia do assoalho pélvico com tela de polipropileno tipo I (Nazca R-Promedon) e Grupo HP- 16 mulheres mulheres submetidas à reconstrução da anatomia do assoalho pélvico com tela de polipropileno tipo I (Nazca R-Promedon) preservando o útero. Raça, urgência miccional, constipação intestinal, dor sacral, sangramento e tempo de operação foram os parâmetros analisados. RESULTADOS: O tempo de seguimento médio foi de nove meses. Não se observou diferença entre os grupos nas complicações funcionais. O tempo cirúrgico foi 120 minutos para grupo HV versus 58.9 minutos para grupo HP ( p < 0.001 ) e o volume de perda sanguínea intraoperatória foi 120 mL no grupo HV versus 20 mL para grupo HP ( p < 0.001*). A taxa de sucesso objetivo foi 86.67% para grupo HV e 75% para grupo HP (p = 0,667). A taxa de erosão de tela foi 20% (3/15) de extrusão no grupo HV versus 18,75% (3/16) no grupo HP (p = 1,000). CONCLUSÃO: A correção cirúrgica do assoalho pélvico com telas nas portadoras de prolapso uterino apresentaram similaridade quer sendo ela feita com histeropexia quer com histerectomia. Contudo, o tempo cirúrgico e o volume da perda sanguínea foram significantemente maiores no grupo com histerectromia (HV). Operações vaginais com telas são procedimentos efetivos para a correção do prolapso.

Laços familiares e aspectos materiais da dinâmica mercantil na cidade de São Paulo (séculos XVIII e XIX)

A partir das relações familiares estabelecidas no seio do grupo mercantil ativo na cidade de São Paulo ao longo dos séculos XVIII e XIX, pretende-se narrar as trajetórias de vida de nove agentes comerciais envolvidos nas alianças matrimoniais, destacando os negócios realizados, a atuação sociopolítica e o encaminhamento dado aos descendentes. Em seguida, busca-se articular o desenvolvimento urbano do centro da capital com a atuação destes homens de negócio, concentrando as análises sobre aspectos da vida material relacionados às suas moradias e ao mobiliário existente no espaço doméstico.

Explaining sleep duration in adolescents: the impact of socio-demographic and lifestyle factors and working status

Previous studies found students who both work and attend school undergo a partial sleep deprivation that accumulates across the week. The aim of the present study was to obtain information using a questionnaire on a number of variables (e.g., socio-demographics, lifestyle, work timing, and sleep-wake habits) considered to impact on sleep duration of working (n=51) and non-working (n=41) high-school students aged 14-21 yrs old attending evening classes (19:00-22:30 h) at a public school in the city of So Paulo, Brazil. Data were collected for working days and days off. Multiple linear regression analyses were performed to assess the factors associated with sleep duration on weekdays and weekends. Work, sex, age, smoking, consumption of alcohol and caffeine, and physical activity were considered control variables. Significant predictors of sleep duration were: work (p < 0.01), daily work duration (8-10 h/day; p < 0.01), sex (p=0.04), age 18-21 yrs (0.01), smoking (p=0.02) and drinking habits (p=0.03), irregular physical exercise (p < 0.01), ease of falling asleep (p=0.04), and the sleep-wake cycle variables of napping (p < 0.01), nocturnal awakenings (p < 0.01), and mid-sleep regularity (p < 0.01). The results confirm the hypotheses that young students who work and attend school showed a reduction in night-time sleep duration. Sleep deprivation across the week, particularly in students working 8-10 h/day, is manifested through a sleep rebound (i.e., extended sleep duration) on Saturdays. However, the different roles played by socio-demographic and lifestyle variables have proven to be factors that intervene with nocturnal sleep duration. ) The variables related to the sleep-wake cycle naps and night awakenings proved to be associated with a slight reduction in night-time sleep, while regularity in sleep and wake-up schedules was shown to be associated with more extended sleep duration, with a distinct expression along the week and the weekend. Having to attend school and work, coupled with other socio-demographic and lifestyle factors, creates an unfavorable scenario for satisfactory sleep duration

Highlights from the I international symposium of thrombosis and anticoagulation in internal medicine, October 23–25, 2008, Sao Paulo, Brazil

Abstract The importance of thrombosis and anticoagulation in clinical practice is rooted firmly in several fundamental constructs that can be applied both broadly and globally. Awareness and the appropriate use of anticoagulant therapy remain the keys to prevention and treatment. However, to assure maximal efficacy and safety, the clinician must, according to the available evidence, choose the right drug, at the right dose, for the right patient, under the right indication, and for the right duration of time. The first International Symposium of Thrombosis and Anticoagulation in Internal Medicine was a scientific program developed by clinicians for clinicians. The primary objective of the meeting was to educate, motivate and inspire internists, cardiologists and hematologists by convening national and international visionaries, thought-leaders and dedicated clinician-scientists in Sao Paulo, Brazil. This article is a focused summary of the symposium proceedings

Emergence of Klebsiella pneumoniae carrying the novel extended-spectrum 'beta'-lactamase gene variants 'bla IND. SHV-40', 'bla IND. TEM-116' and the class I integron-associated 'bla IND. GES-7' in Brazil

A clinical Klebsiella pneumoniae isolate carrying the extended-spectrum beta-lactamase gene variants bla(SHV-40), bla(TEM-116) and bla(GES-7) was recovered. Cefoxitin and ceftazidime activity was most affected by the presence of these genes and an additional resistance to trimethoprim-sulphamethoxazole was observed. The bla(GES-7) gene was found to be inserted into a class 1 integron. These results show the emergence of novel bla(TEM) and bla(SHV) genes in Brazil. Moreover, the presence of class 1 integrons suggests a great potential for dissemination of bla(GES) genes into diverse nosocomial pathogens. Indeed, the bla(GES-7) gene was originally discovered in Enterobacter cloacae in Greece and, to our knowledge, has not been reported elsewhere

Changes in Glucose and Glutamine Lymphocyte Metabolisms Induced by Type I Interferon alpha

In lymphocytes (LY), the well-documented antiproliferative effects of IFN-alpha are associated with inhibition of protein synthesis, decreased amino acid incorporation, and cell cycle arrest. However, the effects of this cytokine on the metabolism of glucose and glutamine in these cells have not been well investigated. Thus, mesenteric and spleen LY of male Wistar rats were cultured in the presence or absence of IFN-alpha, and the changes on glucose and glutamine metabolisms were investigated. The reduced proliferation of mesenteric LY was accompanied by a reduction in glucose total consumption (35%), aerobic glucose metabolism (55%), maximal activity of glucose-6-phosphate dehydrogenase (49%), citrate synthase activity (34%), total glutamine consumption (30%), aerobic glutamine consumption (20.3%) and glutaminase activity (56%). In LY isolated from spleen, IFN alpha also reduced the proliferation and impaired metabolism. These data demonstrate that in LY, the antiproliferative effects of IFN alpha are associated with a reduction in glucose and glutamine metabolisms.

Does Training Laparoscopic Skills in a Virtual Reality Simulator Improve Surgical Performance?

Background and Purpose: Several different methods of teaching laparoscopic skills have been advocated, with virtual reality surgical simulation (VRSS) being the most popular. Its effectiveness in improving surgical performance is not a consensus yet, however. The purpose of this study was to determine whether practicing surgical skills in a virtual reality simulator results in improved surgical performance. Materials and Methods: Fifteen medical students recruited for the study were divided into three groups. Group I (control) did not receive any VRSS training. For 10 weeks, group II trained basic laparoscopic skills (camera handling, cutting skill, peg transfer skill, and clipping skill) in a VRSS laparoscopic skills simulator. Group III practiced the same skills and, in addition, performed a simulated cholecystectomy. All students then performed a cholecystectomy in a swine model. Their performance was reviewed by two experienced surgeons. The following parameters were evaluated: Gallbladder pedicle dissection time, clipping time, time for cutting the pedicle, gallbladder removal time, total procedure time, and blood loss. Results: With practice, there was improvement in most of the evaluated parameters by each of the individuals. There were no statistical differences in any of evaluated parameters between those who did and did not undergo VRSS training, however. Conclusion: VRSS training is assumed to be an effective tool for learning and practicing laparoscopic skills. In this study, we could not demonstrate that VRSS training resulted in improved surgical performance. It may be useful, however, in familiarizing surgeons with laparoscopic surgery. More effective methods of teaching laparoscopic skills should be evaluated to help in improving surgical performance.

An empirical evaluation of imputation accuracy for association statistics reveals increased type-I error rates in genome-wide associations

Background: Genome wide association studies (GWAS) are becoming the approach of choice to identify genetic determinants of complex phenotypes and common diseases. The astonishing amount of generated data and the use of distinct genotyping platforms with variable genomic coverage are still analytical challenges. Imputation algorithms combine directly genotyped markers information with haplotypic structure for the population of interest for the inference of a badly genotyped or missing marker and are considered a near zero cost approach to allow the comparison and combination of data generated in different studies. Several reports stated that imputed markers have an overall acceptable accuracy but no published report has performed a pair wise comparison of imputed and empiric association statistics of a complete set of GWAS markers. Results: In this report we identified a total of 73 imputed markers that yielded a nominally statistically significant association at P < 10(-5) for type 2 Diabetes Mellitus and compared them with results obtained based on empirical allelic frequencies. Interestingly, despite their overall high correlation, association statistics based on imputed frequencies were discordant in 35 of the 73 (47%) associated markers, considerably inflating the type I error rate of imputed markers. We comprehensively tested several quality thresholds, the haplotypic structure underlying imputed markers and the use of flanking markers as predictors of inaccurate association statistics derived from imputed markers. Conclusions: Our results suggest that association statistics from imputed markers showing specific MAF (Minor Allele Frequencies) range, located in weak linkage disequilibrium blocks or strongly deviating from local patterns of association are prone to have inflated false positive association signals. The present study highlights the potential of imputation procedures and proposes simple procedures for selecting the best imputed markers for follow-up genotyping studies.

Expression and cellular localization of microRNA-29b and RAX, an activator of the RNA-dependent protein kinase (PKR), in the retina of streptozotocin-induced diabetic rats

Purpose: The apoptosis of retinal neurons plays a critical role in the pathogenesis of diabetic retinopathy (DR), but the molecular mechanisms underlying this phenomenon remain unclear. The purpose of this study was to investigate the cellular localization and the expression of microRNA-29b (miR-29b) and its potential target PKR associated protein X (RAX), an activator of the pro-apoptotic RNA-dependent protein kinase (PKR) signaling pathway, in the retina of normal and diabetic rats. Methods: Retinas were obtained from normal and diabetic rats within 35 days after streptozotocin (STZ) injection. In silico analysis indicated that RAX is a potential target of miR-29b. The cellular localization of miR-29b and RAX was assessed by in situ hybridization and immunofluorescence, respectively. The expression levels of miR-29b and RAX mRNA were evaluated by quantitative reverse transcription PCR (qRT-PCR), and the expression of RAX protein was evaluated by western blot. A luciferase reporter assay and inhibition of endogenous RAX were performed to confirm whether RAX is a direct target of miR-29b as predicted by the in silico analysis. Results: We found that miR-29b and RAX are localized in the retinal ganglion cells (RGCs) and the cells of the inner nuclear layer (INL) of the retinas from normal and diabetic rats. Thus, the expression of miR-29b and RAX, as assessed in the retina by quantitative RT-PCR, reflects their expression in the RGCs and the cells of the INL. We also revealed that RAX protein is upregulated (more than twofold) at 3, 6, 16, and 22 days and downregulated (70%) at 35 days, whereas miR-29b is upregulated (more than threefold) at 28 and 35 days after STZ injection. We did not confirm the computational prediction that RAX is a direct target of miR-29b. Conclusions: Our results suggest that RAX expression may be indirectly regulated by miR-29b, and the upregulation of this miRNA at the early stage of STZ-induced diabetes may have a protective effect against the apoptosis of RGCs and cells of the INL by the pro-apoptotic RNA-dependent protein kinase (PKR) signaling pathway.

PAR evaluation of treated Class I extraction patients

Objective: To evaluate treatment changes and quality of finishing occlusion in Class I patients treated with four premolar extractions. Material and Methods: Dental casts of 94 subjects (50 males and 44 females) were evaluated. Mean pretreatment age was 13.46 years, and mean treatment time was 2.09 years. The peer assessment rating (PAR) index was obtained from pretreatment and posttreatment dental casts. Results: The mean pretreatment PAR index of 29.46 was reduced to 6.32 at posttreatment stage, achieving a reduction of 78.54% with treatment. There was correlation between the initial PAR and correction during treatment, that is, the more severe the malocclusion the greater the treatment changes. Conclusion: The cases evaluated showed a high-standard orthodontic finishing.