143 resultados para Multiple generation scenarios
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The phospholipases A(1) (PLA(1)s) from the venom of the social wasp Polybia paulista occur as a mixture of different molecular forms. To characterize the molecular origin of these structural differences, an experimental strategy was planned combining the isolation of the pool of PLAs from the wasp venom with proteomic approaches by using 2-D, MALDI-TOF-TOF MS and classical protocols of protein chemistry, which included N- and C-terminal sequencing. The existence of an intact form of PLA(1) and seven truncated forms was identified, apparently originating from controlled proteolysis of the intact protein; in addition to this, four of these truncated forms also presented carbohydrates attached to their molecules. Some of these forms are immunoreactive to specific-IgE, while others are not. These observations permit to raise the hypothesis that naturally occurring proteolysis of PLA(1), combined with protein glycosylation may create a series of different molecular forms of these proteins, with different levels of allergenicity. Two forms of PLA(2)s, apparently related to each other, were also identified; however, it was not possible to determine the molecular origin of the differences between both forms, except that one of them was glycosylated. None of these forms were immunoreactive to human specific IgE.
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Background Meta-analysis is increasingly being employed as a screening procedure in large-scale association studies to select promising variants for follow-up studies. However, standard methods for meta-analysis require the assumption of an underlying genetic model, which is typically unknown a priori. This drawback can introduce model misspecifications, causing power to be suboptimal, or the evaluation of multiple genetic models, which augments the number of false-positive associations, ultimately leading to waste of resources with fruitless replication studies. We used simulated meta-analyses of large genetic association studies to investigate naive strategies of genetic model specification to optimize screenings of genome-wide meta-analysis signals for further replication. Methods Different methods, meta-analytical models and strategies were compared in terms of power and type-I error. Simulations were carried out for a binary trait in a wide range of true genetic models, genome-wide thresholds, minor allele frequencies (MAFs), odds ratios and between-study heterogeneity (tau(2)). Results Among the investigated strategies, a simple Bonferroni-corrected approach that fits both multiplicative and recessive models was found to be optimal in most examined scenarios, reducing the likelihood of false discoveries and enhancing power in scenarios with small MAFs either in the presence or in absence of heterogeneity. Nonetheless, this strategy is sensitive to tau(2) whenever the susceptibility allele is common (MAF epsilon 30%), resulting in an increased number of false-positive associations compared with an analysis that considers only the multiplicative model. Conclusion Invoking a simple Bonferroni adjustment and testing for both multiplicative and recessive models is fast and an optimal strategy in large meta-analysis-based screenings. However, care must be taken when examined variants are common, where specification of a multiplicative model alone may be preferable.
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Dysplasia and esophageal adenocarcinoma may arise in patients with Barrett`s esophagus after fundoplication esophageal pH monitoring showing no acid in esophagus. This suggests the need to develop methodology to evaluate the occurrence of ultra-distal reflux (1 cm above the LES). The objective of the study was to compare acid exposition in three different levels: 5 cm above the upper border of the LES, 1 cm above the LES and in the intrasphincteric region. Eleven patients with Barrett`s esophagus after Nissen fundoplication with no clinical, endoscopic and radiologic evidence of reflux were selected. Four-channel pH monitoring took place: channel A, 5 cm above the upper border of the LES; channel B, 1 cm above the LES; channel C, intrasphincteric; channel D, intragastric. The results of channels A, B and C were compared. There was significant increase in number of reflux episodes and a higher fraction of time with pH <4.0 in channel B compared to channel A. There was significant decrease in fraction of time with pH <4.0 in channel B compared to channel C. Two cases of esophageal adenocarcinoma were diagnosed in the studied patients. The region 1 cm above the upper border of the LES is more exposed to acid than the region 5 cm above the upper border of the LES, although this exposure occurred in reduced levels. The region 1 cm above the upper border of the LES is less exposed to acid than the intrasphincteric region.
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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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Alcohol is an important risk factor for upper aerodigestive cancers and is principally metabolized by alcohol dehydrogenase (ADH) enzymes. We have investigated six ADH genetic variants in over 3,800 aerodigestive cancer cases and 5,200 controls from three individual studies. Gene variants rs1229984 (ADH1B) and rs1573496 (ADH7) were significantly protective against aerodigestive cancer in each individual study and overall (P = 10(-10) and 10(-9), respectively). These effects became more apparent with increasing alcohol consumption (P for trend = 0.0002 and 0.065, respectively). Both gene effects were independent of each other, implying that multiple ADH genes may be involved in upper aerodigestive cancer etiology.
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Rehospitalization is an important outcome of drug effectiveness in schizophrenia. In this study, the hypothesis that clozapine and some second generation antipsychotics (SGA) were superior to first generation antipsychotics (FGA) in preventing rehospitalization of patients with schizophrenia discharged from a university hospital in Brazil was tested. A retrospective observational study was conducted designed to evaluate time to rehospitalization of patients with schizophrenia discharged on a regimen of oral FGA, depot FGA, risperidone, olanzapine and amisulpride, other SGA, or clozapine, during a three-year follow-up period. Risk factors associated with rehospitalization were examined. Of the 464 patients with schizophrenia discharged from hospital, 242 met criteria for study entry. Higher rehospitalization rates were observed in patients treated with depot FGA (30%), risperidone (30%) and other SGA groups (28.5%), respectively. Clozapine was significantly associated with lower rehospitalization risk compared with risperidone. The risk of rehospitalization in patients on olanzapine and amisulpride, and oral FGA, was similar to that of patients in use of clozapine. These results however, are limited by the heterogeneity of illness severity across the groups. (C) 2011 Elsevier Ireland Ltd. All rights reserved.
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Cognitive deficits are a key feature of recent-onset psychosis, but there is no consensus on whether such deficits are generalized or confined to specific domains. Besides, it is unclear whether cognitive deficits: a) are found in psychotic patients in samples from outside high-income countries; and b) whether they progress uniformly over time in schizophrenia and affective psychoses. We applied 12 tests organized into eight cognitive domains, comparing psychosis patients (n = 56, time from initial contact = 677.95+/-183.27 days) versus healthy controls (n = 70) recruited from the same area of Sao Paulo, Brazil. Longitudinal comparisons (digit span and verbal fluency) were conducted between a previous assessment of the subjects carried out at their psychosis onset, and the current follow-up evaluation. Psychosis patients differed significantly from controls on five domains, most prominently on verbal memory. Cognitive deficits remained detectable in separate comparisons of the schizophrenia subgroup and, to a lesser extent, the affective psychosis subjects against controls. Longitudinal comparisons indicated significant improvement in schizophrenia, affective psychoses, and control subjects, with no significant group-by-time interactions. Our results reinforce the view that there are generalized cognitive deficits in association with recent-onset psychoses, particularly of non-affective nature, which persist over time. (C) 2009 Elsevier Ireland Ltd. All rights reserved.
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Intracranial meningioma removal carries a higher risk of post-operative haemorrhage compared with other intracranial neoplasm surgeries. We report a patient who developed three intracranial haematomas following a frontal meningioma removal.
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One of the challenges in screening for dementia in developing countries is related to performance differences due to educational and cultural factors. This study evaluated the accuracy of single screening tests as well as combined protocols including the Mini-Mental State Examination (MMSE), Verbal Fluency animal category (VF), Clock Drawing test (CDT), and Pfeffer Functional Activities Questionnaire (PFAQ) to discriminate illiterate elderly with and without Alzheimer`s disease (AD) in a clinical sample. Cross-sectional study with 66 illiterate outpatients diagnosed with mild and moderate AD and 40 illiterate normal controls. Diagnosis of AD was based on NINCDS-ADRDA. All patients were submitted to a diagnostic protocol including a clinical interview based on the CAMDEX sections. ROC curves area analyses were carried out to compare sensitivity and specificity for the cognitive tests to differentiate the two groups (each test separately and in two by two combinations). Scores for all cognitive (MMSE, CDT, VF) and functional assessments (PFAQ) were significantly different between the two groups (p < 0.001). The best screening instruments for this sample of illiterate elderly were the MMSE and the PFAQ. The cut-off scores for the MMSE, VF, CDT, and PFAQ were 17.5, 7.5, 2.5, and 11.5, respectively. The most sensitive combination came from the MMSE and PFAQ (94.1%), and the best specificity was observed with the combination of the MMSE and CDT (89%). Illiterate patients can be successfully screened for AD using well-known screening instruments, especially in combined protocols.
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Differences in bone mineral density (BMD) patterns have been recently reported between multiple endocrine neoplasia type 1-related primary hyperparathyroidism (HPT/MEN1) and sporadic primary HPT However studies on the early and later outcomes of bone/renal complications in HPT/MEN1 are lacking In this cross sectional study performed in a tertiary academic hospital 36 patients cases with uncontrolled HPT from 8 unrelated MEN1 families underwent dual energy X ray absorptiometry (DXA) scanning of the proximal one third of the distal radius (1/3DR) femoral neck, total hip, and lumbar spine (LS) The mean age of the patients was 389 +/- 145 years Parathyroid hormone (PTH)/calcium values were mildly elevated despite an overall high percentage of bone demineralization (77 8%) In the younger group (<50 years of age) demineralization in the 1/3DR was more frequent more severe and occurred earlier (40% Z-score 1 81 +/- 0 26) The older group (>50 years of age) had a higher frequency of bone demineralization at all sites (p < 005) and a larger number of affected bone sites (p < 0001), and BMD was more severely compromised in the 1/3DR (p = 007) and LS (p= 002) BMD values were lower in symptomatic (88 9%) than in asymptomatic HPT patients (p < 006) Patients with long standing HPT (>10 years) and gastnnoma/HPT presented significantly lower 1/3DR BMD values Urolithiasis occurred earlier (<30 years) and more frequently (75%) and was associated with related renal comorbidities (50%) and renal insufficiency in the older group (33%) Bone mineral- and urolithiasis-related renal complications in HPT/MEN1 are early onset frequent extensive severe and progressive These data should be considered in the individualized clinical/surgical management of patients with MEN1 associated HPT (C) 2010 American Society for Bone and Mineral Research
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BACKGROUND: Treatment recommendations have been developed for management of patients with chronic myeloid leukemia (CML). METHODS: A 30-item multiple-choice questionnaire was administered to 435 hematologists and oncohematologists in 16 Latin American countries. Physicians self-reported their diagnostic, therapeutic, and disease management strategies. RESULTS: Imatinib is available as initial therapy to 92% of physicians, and 42% of physicians have access to both second-generation tyrosine kinase inhibitors. Standard-dose imatinib is the preferred initial therapy for most patients, but 20% would manage a young patient initially with an allogeneic stem cell transplant from a sibling donor, and 10% would only offer hydroxyurea to an elderly patient. Seventy-two percent of responders perform routine cytogenetic analysis for monitoring patients on therapy, and 59% routinely use quantitative polymerase chain reaction. For patients who fail imatinib therapy, 61% would increase the dose of imatinib before considering change to a second-generation tyrosine kinase inhibitor, except for patients aged 60 years, for whom a switch to a second-generation tyrosine kinase inhibitor was the preferred choice. CONCLUSIONS: The answers to this survey provide insight into the management of patients with CML in Latin America. Some deviations from current recommendations were identified. Understanding the treatment patterns of patients with CML in broad population studies is important to identify needs and improve patient care. Cancer 2010;116:4991-5000. (C) 2070 American Cancer Society.
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The purpose of this study was to determine whether bone marrow-derived cells can differentiate into myofibroblasts, as defined by alpha-smooth muscle actin (SMA) expression, that arise in the corneal stroma after irregular phototherapeutic keratectomy and whose presence within the cornea is associated with corneal stromal haze. C578L/6J-GFP chimeric mice were generated through bone marrow transplantation from donor mice that expressed enhanced green fluorescent protein (GFP) in a high proportion of their bone marrow-derived cells. Twenty-four GFP chimeric mice underwent haze-generating corneal epithelial scrape followed by irregular phototherapeutic keratectomy (PTK) with an excimer laser in one eye. Mice were euthanized at 2 weeks or 4 weeks after PTK and the treated and control contralateral eyes were removed and cryo-preserved for sectioning for immunocytochemistry. Double immunocytochemistry for GFP and myofibroblast marker alpha-smooth muscle actin (SMA) were performed and the number of SMA+GFP+, SMA+GFP, SMA-GFP+ and SMA GFP cells, as well as the number of DAPI+ cell nuclei, per 400x field of stroma was determined in the central, mid-peripheral and peri-limbal cornea. In this mouse model, there were no SMA+ cells and only a few GFP+ cells detected in unwounded control corneas. No SMA+ cells were detected in the stroma at two weeks after irregular PTK, even though there were numerous GFP+ cells present. At 4 weeks after irregular PTK, all corneas developed mild to moderately severe corneal haze. In each of the three regions of the corneas examined, there were on average more than 9x more SMA+GFP+ than SMA+GFP myofibroblasts. This difference was significant (p < 0.01). There were significantly more (p < 0.01) SMA GFP+ cells, which likely include inflammatory cells, than SMA+GFP+ or SMA+GFP cells, although SMA GFP cells represent the largest population of cells in the corneas. In this mouse model, the majority of myofibroblasts developed from bone marrow-derived cells. It is possible that all myofibroblasts in these animals developed from bone marrow-derived cells since mouse chimeras produced using this method had only 60-95% of bone marrow-derived cells that were GFP+ and it is not possible to achieve 100% chimerization. This model, therefore, cannot exclude the possibility of myofibroblasts also developed from keratocytes and/or corneal fibroblasts. (C) 2010 Elsevier Ltd. All rights reserved.
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Federico Foundation
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Posttransplantation lymphoproliferative disorder (PTLD) is a serious complication following solid organ transplantation that has been linked to Epstein-Barr virus (EBV) infection. The aim of this article was to describe a single-center experience with the multiplicity of clinical presentations of PTLD. Among 350 liver transplantations performed in 303 children, 13 survivor children displayed a histological diagnosis of PTLD (13/242 survivors; 5.4%). The age at diagnosis ranged from 12 to 258 months (median, 47), and the time from transplantation ranged from 1 to 84 months (median, 13). Ten of these children (76.9%) were EBV-naive prior to transplantation. Fever was present in all cases. The clinical signs at presentation were anemia (92.3%), diarrhea and vomiting (69.2%), recurrent upper airway infections (38.4%), Waldeyer ring lymphoid tissue hypertrophy (23.0%), abdominal mass lesions (30.7%), massive cervical and mediastinal adenopathy (15.3%), or gastrointestinal and respiratory symptoms (30.7%). One child developed fulminant hepatic allograft failure secondary to graft involvement by PTLD. Polymorphic PTLD was diagnosed in 6 patients; 7 had the diagnosis of lymphoma. Treatment consisted of stopping immunosuppression as well as starting intravenous gancyclovir and anti-CD20 monoclonal antibody therapy. The mortality rate was 53.8%. The clinical presentation of PTLD varied from fever of unknown origin to fulminant hepatic failure. The other symptoms that may be linked to the diagnosis of PTLD are pancytopenia, tonsil and adenoid hypertrophy, cervical or mediastinal lymph node enlargement, as well as abdominal masses. Despite numerous advances, the optimal treatment approach for PTLD is not completely known and the mortality rate is still high.
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P>Objective Limited data have been reported on the effect of parathyroidectomy (PTx) on bone mineral density (BMD) in the setting of patients with hyperparathyroidism (HPT) associated with multiple endocrine neoplasia type 1 (MEN1). This study investigates the impact of total PTx on BMD in patients with HPT/MEN1. Design and patients A case series study was performed in a tertiary academic hospital. A total of 16 HPT/MEN1 patients from six families harbouring MEN1 germline mutations were subjected to total PTx followed by parathyroid auto-implant in the forearm. Measurements Bone mineral density values were assessed using dual-energy X-ray absorptiometry. Results Before PTx, reduced BMD (Z-score <-2 center dot 0) was highly prevalent in the proximal one-third of the distal radius (1/3 DR) (50%), lumbar spine (LS) (43 center dot 7%), ultradistal radius (UDR) (43 center dot 7%), femoral neck (FN) (25%) and total femur (TF) (18 center dot 7%) in the patients. Fifteen months after PTx, we observed a BMD improvement in the LS (from 0 center dot 843 to 0 center dot 909 g/cm2; +8 center dot 4%, P = 0 center dot 001), FN (from 0 center dot 745 to 0 center dot 798 g/cm2; +7 center dot 7%, P = 0 center dot 0001) and TF (from 0 center dot 818 to 0 center dot 874 g/cm2; +6 center dot 9%, P < 0 center dot 0001). No significant change was noticed in the 1/3 DR and UDR after PTx. Conclusions This data confirmed BMD recovery in the LS and FN after PTx in HPT/MEN1 patients. We also documented a significant BMD increase in the TF and no change in both the 1/3 DR and UDR BMD after PTx. Our data suggest that LS and proximal femur are the most informative sites to evaluate the short-term BMD outcome after PTx in HPT/MEN1 subjects.