905 resultados para Interval censoring


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XPC participates in the initial recognition of DNA damage during the DNA nucleotide excision repair process in global genomic repair. Polymorphisms in XPC gene have been analyzed in case-control studies to assess the cancer risk attributed to these variants, but results are conflicting. To clarify the impact of XPC polymorphisms in cancer risk, we performed a meta-analysis that included 33 published case-control studies. Polymorphisms analyzed were Lys939Gln and Ala499Val. The overall summary odds ratio (OR) for the associations of the 939Gln/Gln genotype with risk of cancer was 1.01 (95% confidence interval (95% CI): 0.94-1.09), but there were statistically significant associations for lung cancer, observed for the recessive genetic model (Lys/Lys + Lys/Gln vs Gln/Gln), (OR 1.30; 95% CI: 1.113-1.53), whereas for breast cancer a reduced but nonsignificant risk was observed for the same model (OR 0.87; 95% CI: 0.74-1.01). The results for Ala499Val showed a significant overall increase in cancer risk (OR 1.15; 95% CI: 1.02-1.31), and for bladder cancer in both the simple genetic model (Ala/Ala vs Val/Val) (OR 1.30; 95% CI: 1.04-1.61) and the recessive genetic model (Ala/Ala + Ala/Val vs Val/Val) (OR 1.32; 95% CI: 1.06-1.63). Our meta-analysis supports that polymorphisms in XPC may represent low-penetrance susceptibility gene variants for breast, bladder, head and neck, and lung cancer. XPC is a good candidate for large-scale epidemiological case-control studies that may lead to improvement in the management of highly prevalent cancers.

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Fogo selvagem (FS) is mediated by pathogenic, predominantly IgG4, anti-desmoglein 1 (Dsg1) autoantibodies and is endemic in Limao Verde, Brazil. IgG and IgG subclass autoantibodies were tested in a sample of 214 FS patients and 261 healthy controls by Dsg1 ELISA. For model selection, the sample was randomly divided into training (50%), validation (25%), and test (25%) sets. Using the training and validation sets, IgG4 was chosen as the best predictor of FS, with index values above 6.43 classified as FS. Using the test set, IgG4 has sensitivity of 92% (95% confidence interval (95% CI): 82-95%), specificity of 97% (95% CI: 89-100%), and area under the curve of 0.97 ( 95% CI: 0.94-1.00). The IgG4 positive predictive value (PPV) in Limao Verde (3% FS prevalence) was 49%. The sensitivity, specificity, and PPV of IgG anti-Dsg1 were 87, 91, and 23%, respectively. The IgG4-based classifier was validated by testing 11 FS patients before and after clinical disease and 60 Japanese pemphigus foliaceus patients. It classified 21 of 96 normal individuals from a Limao Verde cohort as having FS serology. On the basis of its PPV, half of the 21 individuals may currently have preclinical FS and could develop clinical disease in the future. Identifying individuals during preclinical FS will enhance our ability to identify the etiological agent(s) triggering FS.

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Objectives: To determine the effect of maternal smoking during pregnancy on transient evoked otoacoustic emissions levels in neonates. Methods: This was a cross-sectional study investigating neonates in the maternity ward of a university hospital in the city of Sao Paulo, Brazil. A total of 418 term neonates without prenatal or perinatal complications were evaluated. The neonates were divided into two groups: a study group, which comprised 98 neonates born to mothers who had smoked during pregnancy; and a control group, which comprised 320 neonates born to mothers who had not. In order to compare the two ears and the two groups in terms of the mean overall response and the mean transient evoked otoacoustic emissions in response to acoustic stimuli delivered at different frequencies, we used analysis of variance with repeated measures. Results: The mean overall response and the mean frequency-specific response levels were lower in the neonates in the study group (p < 0.001). The mean difference between the groups was 2.47 dB sound pressure level (95% confidence interval: 1.47-3.48). Conclusions: Maternal smoking during pregnancy had a negative effect on cochlear function, as determined by otoacoustic emissions testing. Therefore, pregnant women should be warned of this additional hazard of smoking. It is important that smoking control be viewed as a public health priority and that strategies for treating tobacco dependence be devised. (C) 2011 Elsevier Ireland Ltd. All rights reserved.

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Objectives: To estimate the prevalence of fibromyalgia (FM) and chronic widespread pain (CWP) in community-dwelling elderly individuals living in Sao Paulo, to assess the spectrum of problems related to these diseases using the Fibromyalgia Impact Questionnaire (FIQ) and to correlate the FIQ with the number of tender points and with pain threshold. Methods: Our sample consisted of 361 individuals (64% women, 36% men, mean age of 73.3 +/- 5.7 years). Individuals were classified into four groups: FM (according to American College of Rheumatology criteria), CWP, regional pain (RP) and no pain (NP). Pain characteristics and dolorimetry for 18 tender points and the FIQ were assessed. Results: The prevalence of FM was 5.5% [95% confidence interval (CI) = 5.4-5.7], and the prevalence of CWP was 14.1% (95% Cl: 10.5-17.7%). The frequency of RP was 52.6% and the prevalence of NP was 27.7%. FIQ scores were higher in people with FM (44.5), followed by CWP (31.4), RP (18.1) and NP (5.5) (p < 0.001). There was a positive correlation between the domains of the FIQ and the number of tender Points (p < 0.05), and a negative correlation between FIQ score and pain threshold (p < 0.05). Conclusion: In our elderly subjects, the prevalence of FM was slightly higher compared to previously reported studies, and CWP was around 14%. The spectrum of problems related to chronic pain was more severe in FM followed by CWP, strongly suggesting that these conditions should be diagnosed and adequately treated in older individuals. (C) 2010 Elsevier Ireland Ltd. All rights reserved.

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Analysis of a major multi-site epidemiologic study of heart disease has required estimation of the pairwise correlation of several measurements across sub-populations. Because the measurements from each sub-population were subject to sampling variability, the Pearson product moment estimator of these correlations produces biased estimates. This paper proposes a model that takes into account within and between sub-population variation, provides algorithms for obtaining maximum likelihood estimates of these correlations and discusses several approaches for obtaining interval estimates. (C) 1997 by John Wiley & Sons, Ltd.

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Management of rectal cancer has become increasingly complex and a multidisciplinary approach is considered of key importance for improving outcomes. A national survey among specialists involved in this multidisciplinary setting was performed. A web-based survey containing 11 questions regarding rectal cancer management was sent to surgeons and medical oncologists registered by their corresponding societies as members. Statistical analysis was performed using the chi-square and Fisher`s exact tests for all categorical variables according to response to individual questions. Multivariate analysis was performed using Cox`s logistic regression. Overall, 418 email recipients responded the survey. Local staging was performed without either magnetic resonance imaging or endorectal ultrasound by 64% of responders. Seventy-two percent considered that final management decision should be made after neoadjuvant chemoradiation therapy. Additionally, 46% considered that an alternative procedure (local excision or observation) was appropriate in a patient with a complete clinical response. Colorectal surgeons were more frequently in favor of longer intervals after completion of chemoradiation therapy (P = 0.001) and of alternative management procedures after a complete clinical response (P = 0.02). After multivariate analysis, the choice of a watch and wait approach after a complete clinical response following neoadjuvant chemoradiation therapy was significantly more frequent among surgeons (OR 3.5, 95% CI 1.8-7.1). Surgeons seem to be more in favor of tailoring management of rectal cancer according to tumor response after neoadjuvant chemoradiation therapy, with longer intervals after chemoradiation therapy, decisions about treatment strategy being made after chemoradiation therapy instead of before, and the use of alternative surgical procedures after a complete clinical response following neoadjuvant therapy.

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BACKGROUND: Complete tumor regression may develop after neoadjuvant chemoradiation therapy for distal rectal cancer. Studies have suggested that selected patients with complete clinical response may avoid radical surgery and close surveillance may provide good outcomes with no oncologic compromise. However, definition of complete clinical response is often imprecise and may vary between different studies. The aim of this study is to provide a clear definition for a complete clinical response after neoadjuvant chemoradiation therapy in patients with distal rectal cancer in addition to actual endoscopic videos from patients managed nonoperatively. METHODS: Patients with nonmetastatic distal rectal cancer treated by neoadjuvant chemoradiation therapy, including 50.4 Gy and concomitant 5-fluorouracil and leucovorin, were assessed for tumor response at least 8 weeks after chemoradiation therapy completion. Complete and incomplete clinical responses were defined based on clinical and endoscopic findings. Patients with complete clinical response were not immediately operated on and were closely followed. Early and late endoscopic findings were recorded. RESULTS: Definition of a complete clinical response should be based on very strict clinical and endoscopic criteria. The finding of any residual superficial ulceration, irregularity, or nodule should prompt surgical attention, including transanal full-thickness excision or even a radical resection with total mesorectal excision. Standard or incisional biopsies should be avoided in this setting. Complete clinical responders should harbor no more than whitening of the mucosa, teleangiectasia with mucosal integrity to be considered for a nonoperative approach. In the presence of these findings, regularly scheduled reassessments may provide a safe alternative to these patients with early detection of recurrent disease. CONCLUSION: Strict definition of the clinical and endoscopic findings of patients experiencing complete clinical response after neoadjuvant chemoradiation therapy may provide a useful tool for the understanding of outcomes of patients managed with no immediate surgery allowing standardization of classifications and comparison between the experiences of different institutions.

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The identification of genes responsible for the rare cases of familial leukemia may afford insight into the mechanism underlying the more common sporadic occurrences. Here we test a single family with 11 relevant meioses transmitting autosomal dominant acute myelogenous leukemia (AML) and myelodysplasia for linkage to three potential candidate loci. In a different family with inherited AML, linkage to chromosome 21q22.1-22.2 was recently reported; we exclude linkage to 21q22.1-22.2, demonstrating that familial AML is a heterogeneous disease. After reviewing familial leukemia and observing anticipation in the form of a declining age of onset with each generation, we had proposed 9p21-22 and 16q22 as additional candidate loci. Whereas linkage to 9p21-22 can be excluded, the finding of a maximum two-point LOD score of 2.82 with the microsatellite marker D16S522 at a recombination fraction theta = 0 provides evidence supporting linkage to 16q22. Haplotype analysis reveals a 23.5-cM (17.9-Mb) commonly inherited region among all affected family members extending from D16S451 to D1GS289, In order to extract maximum linkage information with missing individuals, incomplete informativeness with individual markers in this interval, and possible deviance from strict autosomal dominant inheritance, we performed nonparametric linkage analysis (NPL) and found a maximum NPL statistic corresponding to a P-value of .00098, close to the maximum conditional probability of linkage expected for a pedigree with this structure. Mutational analysis in this region specifically excludes expansion of the AT-rich minisatellite repeat FRA16B fragile site and the CAG trinucleotide repeat in the E2F-4 transcription factor. The ''repeat expansion detection'' method, capable of detecting dynamic mutation associated with anticipation, more generally excludes large CAG repeat expansion as a cause of leukemia in this family.

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The present study aimed to demonstrate conditioned inhibition of Pavlovian conditioning of autonomic responses in humans. Subjects (N = 21) were presented initially with four geometric shapes (A, B, C and D). An electric shock served as the unconditioned stimulus (US) during acquisition. Conditional stimuli lasted for 8 s and US onset coincided with CS offset. Subjects were trained with A-US, C-US, and AC-US pairings and AB alone and B alone presentations. The subsequent summation test consisted of C-US pairings and CB alone and CD alone presentations. Conditioning was evident in self-reported US expectancy and first and second interval electrodermal responses. Evidence for conditioned inhibition during the summation test was found in US expectancy and second interval electrodermal responses. (C) 1997 Elsevier Science B.V.

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Background and Aims: Although the metabolic risk factors for non-alcoholic fatty liver disease (NAFLD) progression have been recognized, the role of genetic susceptibility remains a field to be explored. The aim of this study was to examine the frequency of two polymorphisms in Brazilian patients with biopsy-proven simple steatosis or non-alcoholic steatohepatitis (NASH): -493 G/T in the MTP gene, which codes the protein responsible for transferring triglycerides to nascent apolipoprotein B, and -129 C/T in the GCLC gene, which codes the catalytic subunit of glutamate-cystein ligase in the formation of glutathione. Methods: One hundred and thirty-one biopsy-proven NAFLD patients (n = 45, simple steatosis; n = 86, NASH) and 141 unrelated healthy volunteers were evaluated. Genomic DNA was extracted from peripheral blood cells, and the -129 C/T polymorphism of the GCLC gene was determined by restriction fragment length polymorphism (RFLP). The -493 G/T polymorphism of the MTP gene was determined by direct sequencing of the polymerase chain reaction products. Results: The presence of at least one T allele in the -129 C/T polymorphism of the GCLC gene was independently associated with NASH (odds ratio 12.14, 95% confidence interval 2.01-73.35; P = 0.007), whereas, the presence of at least one G allele in the -493 G/T polymorphism of the MTP gene differed slightly between biopsy-proven NASH and simple steatosis. Conclusion: This difference clearly warrants further investigation in larger samples. These two polymorphisms could represent an additional factor for consideration in evaluating the risk of NAFLD progression. Further studies involving a larger population are necessary to confirm this notion.

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OBJECTIVE. To identify risk factors associated with nosocomial bloodstream infections caused by multiple clones of the staphylococcal cassette chromosome mec (SCCmec) type IV strain of methicillin-resistant Staphylococcus aureus (MRSA). DESIGN. An unmatched case-control study (at a ratio of 1 : 2) performed during the period from October 2002 through September 2003. SETTING. A 2,000-bed tertiary care teaching hospital affiliated with the University of Sao Paulo in Sao Paulo, Brazil. METHODS. Case patients (n = 30) were defined either as patients who had a bloodstream infection due to SCCmec type IV strains of MRSA diagnosed at least 48 hours after hospital admission or as neonates with the infection who were born in the hospital. Control patients (n = 60) were defined as patients with SCCmec type III MRSA infection diagnosed at least 48 hours after hospital admission. Genes n = 60 encoding virulence factors were studied in the isolates recovered from case patients, and molecular typing of the SCCmec type IV MRSA isolates was also done by pulsed-field gel electrophoresis and multilocus sequence typing. RESULTS. In multivariate analysis, the following 3 variables were significantly associated with having a nosocomial bloodstream infection caused by SCCmec type IV strains of MRSA: an age of less than 1 year, less frequent use of a central venous catheter (odds ratio [OR], 0.07 [95% confidence interval {CI}, 0.02-0.28]; P = .001), and female sex. A second analysis was performed that excluded the case and Pp. 001 control patients from the neonatal unit, and, in multivariate analysis, the following variables were significantly associated with having a nosocomial bloodstream infection caused by SCCmec type IV strains of MRSA: less frequent use of a central venous catheter (OR, 0.12 [95% CI, 0.03-0.55]; P = .007), lower Acute Physiology and Chronic Health Evaluation II score on admission (OR, 0.14 [95% CI, 0.03-0.61];), less frequent surgery (OR, 0.21 [95% CI, 0.06-0.83];), and female sex (OR, 5.70 [95% CI, 1.32-24.66]; P =.020). P = .009 Pp. 025 Pp). Of the 29 SCCmec type IV MRSA isolates recovered from case patients, none contained the Panton-Valentine leukocidin, gamma-hemolysin, enterotoxin B or C, or toxic shock syndrome toxin-1. All of the isolates contained genes for the LukE-LukD leukocidin and alpha-hemolysin. Genes for enterotoxin A were present in 1 isolate, and genes for beta-hemolysin were present in 3 isolates. CONCLUSIONS. ""Classical"" risk factors do not apply to patients infected with the SCCmec type IV strain of MRSA, which is an important cause of nosocomial bacteremia. This strain infects a patient population that is less ill and has had less frequent invasive procedures than a patient population infected with the multidrug-resistant strain of SCCmec type III MRSA. We found that virulence factors were rare and that Panton-Valentine leukocidin was absent. There were multiple clones of the SCCmec type IV strain in our hospital. Children under 1 year of age were at a higher risk. There was a predominant clone ( sequence type 5) in this patient population.

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Kaposi`s sarcoma-associated herpesvirus (KSHV) is endemic in the Amazon and rare in southern regions of Brazil. However, geographical distribution and epidemiological correlates of infection in this large country are still poorly defined. To estimate the seroprevalence of, and risk factors for, KSHV infection in Brazil, a multi-center study was conducted among 3,493 first-time voluntary unpaid blood donors from Salvador, Sao Paulo and Manaus. Antibodies against KSHV were detected using a whole-virus ELISA validated prior to the serosurvey. Antibodies against the latency-associated nuclear antigen (LANA) were detected by immuno-fluorescence assay (IFA) among ELISA-positive sera and a random sample of ELISA-negative sera. Overall, seroprevalence of KSHV by whole-virus ELISA was 21.7% (95% confidence interval (Cl): 20-23.4%) in men and 31.7% (95% Cl: 29-34.3%) in women (P<0.0001). KSHV antibodies were detected by IFA-LANA in 3% (95% Cl: 2-4.3%) of 867 ELISA-positive samples and in none of 365 randomly selected ELISA-negative samples. In multivariate analysis, KSHV seroprevalence by whole-virus ELISA was independently associated with female sex (odds ratio [OR] = 1.6, 95% Cl: 1.4-1.9); residence in the Amazon (OR = 1.4, 95% Cl: 1.2-1.8; compared to Salvador); Caucasian ethnicity (OR = 1.3, 95% Cl: 1.1-1.6) and herpes simplex virus type 2 (HSV-2) infection (OR = 1.3, 95% Cl: 1.1-1.6). KSHV seroprevalence did not significantly increase with age, nor was it associated with self-reported sexual behavior. KSHV seroprevalence is high among Brazilian blood donors, particularly from the Amazon region. This study supports the co-existence of sexual and non-sexual routes of KSHV transmission in this population.

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Both hysterectomy and tubal sterilisation offer significant protection from ovarian cancer, and the risk of cardiovascular disease in women is lowered after hysterectomy. Since little is known about the accuracy of women's self-reports of these procedures, we assessed their reliability and validity using data obtained in a case-control study of ovarian cancer. There was 100 per cent repeatability for both positive and negative histories of hysterectomy and tubal sterilisation among a small sample of women on reinterview. Verification of surgery was sought against surgeons' or medical records, or if these were unavailable, from randomly selected current general practitioners for 51 cases and 155 controls reporting a hysterectomy and 73 cases and 137 controls reporting a tubal sterilisation. Validation rate for self-reported hysterectomy against medical reports (32 cases, 96 controls) was 96 per cent (95 per cent confidence interval (CI) 91 to 99) and for tubal sterilisation (32 cases, 77 controls) it was 88 per cent (CI 81 to 93), which is likely to be an underestimate. Although findings are based on small numbers of women for whom medical reports could be ascertained, they are consistent with other findings that suggest women have good recall of past histories of hysterectomy and tubal sterilisation; this allows long-term effects of these procedures to be studied with reasonable accuracy from self-reports.

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Although prophylaxis is current practice, there are no randomized controlled studies evaluating preoperative antimicrobial prophylaxis in dental procedures in patients immunocompromised by chemotherapy or organ transplants. To evaluate prophylaxis in dental-invasive procedures in patients with cancer or solid organ transplants, 414 patients were randomized to receive one oral 500-mg dose 2 hours before the procedure (1-dose group) or a 500-mg dose 2 hours before the procedure and an additional dose 8 hours later (2-dose group). Procedures were exodontia or periodontal scaling/root planing. Follow-up was 4 weeks. No deaths or surgical site infections occurred. Six patients (1.4%) presented with use of pain medication > 3 days or hospitalization during follow-up: 4 of 207 (2%) in the 1-dose group and 2 of 207 (1%) in the 2-dose group (relative risk, 2.02; 95% confidence interval, 0.37-11.15). In conclusion, no statistically significant difference occurred in outcome using 1 or 2 doses of prophylactic amoxicillin for invasive dental procedures in immunocompromised patients.

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Aims: The incidence of head and neck cancer (HNC) in Brazil has increased substantially in recent years. This increase is likely to be strongly associated with alcohol and tobacco consumption, but genetic susceptibility also should be investigated in this population. The aim of this study was to evaluate the association of polymorphisms in genes of alcohol metabolism enzymes and the risk of HNC. Methods: A hospital-based case-control study was conducted in Sao Paulo, Brazil. We here investigated ADH1C Ile(350)Val, ADH1B Arg(48)His, ADH1B Arg(370)Cys and CYP2E1*5A PstI polymorphisms by PCR-RFLP Polymerase Chain Reaction - Restriction Fragment Length Polymorphism in 207 histopathologically confirmed HNC cases (184 males and 23 females) and 244 cancer-free controls (225 males and 19 females) admitted as in-patients in the same hospital. Results: Chronic alcohol intake increased approximately four times the risk of HNC. The mutant genotype ADH1B Arg(48)His was more frequent in controls (12.7%) than HNC patients (5.8%) conferring protection for the disease (odds ratio (OR) = 0.42; 95% confidence interval (CI ), 0.21-0.85). Similar results were observed for individuals with ADH1B*2 (OR = 0.41; 95% CI , 0.20-0.82) or ADH1B*2/ADH1C*1 (OR = 0.32; 95% CI , 0.13-0.79) mutated haplotypes. Multiple regression analyses showed that individuals with the mutant genotype ADH1B Arg(48)His who consume alcohol > 30 g/L/day have more than four times the risk for HNC (OR = 4.42; 95% CI, 1.21-16.11). Conclusions: The fast alcohol metabolizing genotypes may prevent HNC when the amount of alcohol intake is < 30.655 g/L/day.