156 resultados para lower estimate
Resumo:
Numerous studies have found deficits in premorbid IQ in schizophrenic patients, but it is not clear whether this deficit is shared by (a) patients with other functional psychoses, and (b) relatives of these patients. Ninety-one schizophrenic patients, 66 affective psychotic patients (29 schizoaffective and 37 manic or depressed), and 50 normal control subjects were administered the National Adult Reading Test (NART) which provides an estimate of premorbid IQ. The NART was also completed by 85 first-degree relatives of schizophrenic patients and by 65 first-degree relatives of affective psychotic patients. After adjustments were made for sex, social class, ethnicity and years of education, schizophrenic patients had significantly lower premorbid IQ than their relatives, the affective psychotic patients and controls. Manic and depressed patients had significantly lower NART scores than their first-degree relatives, but schizoaffective patients did not, and neither group differed significantly from controls. There was no significant difference in premorbid IQ between patients who had experienced obstetric complications (OC +) and those who had not (OC -). Both OC + and OC - schizophrenic patients differed significantly from their relatives, but the disparity was greatest between OC + patients and their relatives. Relatives of OC + schizophrenic patients had significantly higher IQ than relatives of OC - schizophrenic patients. (C) 2000 Elsevier Science B.V. All rights reserved.
Resumo:
This cross-sectional study assessed relationships between plasma homocysteine, 'thermolabile' methylenetetrahydrofolatereductase (MTHFR) genotype, B vitamin status and measures of renal function in elderly (70-89 years) and nonagenarian (90+ years) subjects, with the hypothesis that octo/nonagenarian subjects who remain healthy into old age as defined by 'Senieur' status might show reduced genetic or environmental risk factors usually associated with hyperhomocysteinaemia. Plasma homocysteine was 9.1 micromol/l (geometric mean [GM]) for all elderly subjects. Intriguingly, homocysteine was significantly lower in 90+ (GM; 8.2 micromol/l) compared to 70-89-year-old subjects (GM; 9.8 micromol/l) despite significantly lower glomerular filtration rate (GFR) and serum B12 in nonagenarian subjects and comparable MTHFR thermolabile (TT) genotype frequency, folate and B6 status to 70-89-year-olds. For all elderly subjects, the odds ratio and 95% confidence intervals for plasma homocysteine being in the highest versus lowest quartile was 4.27 (2.04-8.92) for age 90 years, 3.4 (1.5-7.8) for serum folate 10.7nmol/l, 3.0 (0.9-10.2) for creatinine >140 compared
Resumo:
Event-related potentials (ERPs) and other electroencephalographic (EEG) evidence show that frontal brain areas of higher and lower socioeconomic status (SES) children are recruited differently during selective attention tasks. We assessed whether multiple variables related to self-regulation (perceived mental effort) emotional states (e.g., anxiety, stress, etc.) and motivational states (e.g., boredom, engagement, etc.) may co-occur or interact with frontal attentional processing probed in two matched-samples of fourteen lower-SES and higher-SES adolescents. ERP and EEG activation were measured during a task probing selective attention to sequences of tones. Pre- and post-task salivary cortisol and self-reported emotional states were also measured. At similar behavioural performance level, the higher-SES group showed a greater ERP differentiation between attended (relevant) and unattended (irrelevant) tones than the lower-SES group. EEG power analysis revealed a cross-over interaction, specifically, lower-SES adolescents showed significantly higher theta power when ignoring rather than attending to tones, whereas, higher-SES adolescents showed the opposite pattern. Significant theta asymmetry differences were also found at midfrontal electrodes indicating left hypo-activity in lower-SES adolescents. The attended vs. unattended difference in right midfrontal theta increased with individual SES rank, and (independently from SES) with lower cortisol task reactivity and higher boredom. Results suggest lower-SES children used additional compensatory resources to monitor/control response inhibition to distracters, perceiving also more mental effort, as compared to higher-SES counterparts. Nevertheless, stress, boredom and other task-related perceived states were unrelated to SES. Ruling out presumed confounds, this study confirms the midfrontal mechanisms responsible for the SES effects on selective attention reported previously and here reflect genuine cognitive differences.
Resumo:
Data from animal models indicate that neonatal stress or pain can permanently alter subsequent behavioral and/or physiological reactivity to stressors. However, cumulative effects of pain related to acute procedures in the neonatal intensive care unit (NICU) on later stress and/or pain reactivity has received limited attention. The objective of this study is to examine relationships between prior neonatal pain exposure (number of skin breaking procedures), and subsequent stress and pain reactivity in preterm infants in the NICU. Eighty-seven preterm infants were studied at 32 (+/-1 week) postconceptional age (PCA). Infants who received analgesia or sedation in the 72 h prior to each study, or any postnatal dexamethasone, were excluded. Outcomes were infant responses to two different stressors studied on separate days in a repeated measures randomized crossover design: (1) plasma cortisol to stress of a fixed series of nursing procedures; (2) behavioral (Neonatal Facial Coding System; NFCS) and cardiac reactivity to pain of blood collection. Among infants born
Resumo:
OBJECTIVES: To compare predictors of hospitalization and death in nursing home residents with pneumonia and other lower respiratory infections (LRIs). DESIGN: A nested cohort study. SETTING: Nine nursing homes in southern Ontario. PARTICIPANTS: Three hundred fifty-three nursing home residents with LRIs (enrolled in the control arm of a clinical trial). MEASUREMENTS: Comorbidities, vaccination status, age, health-related quality of life, functional status, and vital statistics were evaluated as potential predictors of hospitalization and mortality at 30 days. RESULTS: Moderate to high disease severity score on a practical severity scale was a strong independent predictor of hospitalization (odds ratio (OR)=7.12, P
Resumo:
Objective: Acquired pit-like changes of the optic nerve head (APON) are characteristic of glaucomatous damage and may be a sign of a localized susceptibility of the optic nerve. Thus, it is possible that biomechanical properties of the ocular tissues may play a pressure-independent role in the pathogenesis of glaucoma. Corneal hysteresis (CH) appears to provide information of the biomechanical properties of the ocular hull tissues. The purpose of this study was to compare CH of patients with primary open angle glaucoma (POAG) with and without APON. Methods: A prospective case control study was done. POAG patients with and without APON were measured using the Ocular Response Analyzer by masked investigators. Patients in both groups were matched for sex, age, corneal thickness, and type of glaucoma according to maximal IOP (NTG or POAG). Statistical analysis was done using ANOVA. Results: Corneal hysteresis of 16 glaucomatous eyes with APON and 32 controls (glaucoma without APON) was measured. The mean (±SD) CH in the APON group was 8.89 (±1.53) and 10.2 (±1.05) in the control group. The difference is statistically significant (p = 0.005). Conclusions: Corneal hysteresis in POAG patients with APON was significantly lower than in patients that did not have such structural changes of the optic disc. These findings may reflect pressure-independent mechanisms involved in the pathogenesis of such glaucomatous optic nerve changes. © Springer-Verlag 2007.
Resumo:
The study of interrelationships between soil structure and its functional properties is complicated by the fact that the quantitative description of soil structure is challenging. Soil scientists have tackled this challenge by taking advantage of approaches such as fractal geometry, which describes soil architectural complexity through a scaling exponent (D) relating mass and numbers of particles/aggregates to particle/aggregate size. Typically, soil biologists use empirical indices such as mean weight diameters (MWD) and percent of water stable aggregates (WSA), or the entire size distribution, and they have successfully related these indices to key soil features such as C and N dynamics and biological promoters of soil structure. Here, we focused on D, WSA and MWD and we tested whether: D estimated by the exponent of the power law of number-size distributions is a good and consistent correlate of MWD and WSA; D carries information that differs from MWD and WSA; the fraction of variation in D that is uncorrelated with MWD and WSA is related to soil chemical and biological properties that are thought to establish interdependence with soil structure (e.g., organic C, N, arbuscular mycorrhizal fungi). We analysed observational data from a broad scale field study and results from a greenhouse experiment where arbuscular mycorrhizal fungi (AMF) and collembola altered soil structure. We were able to develop empirical models that account for a highly significant and large portion of the correlation observed between WSA and MWD but we did not uncover the mechanisms that underlie this correlation. We conclude that most of the covariance between D and soil biotic (AMF, plant roots) and abiotic (C. N) properties can be accounted for by WSA and MWD. This result implies that the ecological effects of the fragmentation properties described by D and generally discussed under the framework of fractal models can be interpreted under the intuitive perspective of simpler indices and we suggest that the biotic components mostly impacted the largest size fractions, which dominate MWD, WSA and the scaling exponent ruling number-size distributions. (C) 2010 Elsevier Ltd. All rights reserved.
Resumo:
Aims. To examine the antioxidant and anti-inflammatory effects of pomegranate polyphenols in obese patients with type 2 diabetes (T2DM) (n = 8) and in healthy nondiabetic controls (n = 9). Methods. Participants received 2 capsules of pomegranate polyphenols (POMx, 1 capsule = 753?mg polyphenols) daily for 4 weeks. Blood draws and anthropometrics were performed at baseline and at 4 weeks of the study. Results. Pomegranate polyphenols in healthy controls and in T2DM patients did not significantly affect body weight and blood pressure, glucose and lipids. Among clinical safety profiles, serum electrolytes, renal function tests, and hematological profiles were not significantly affected by POMx supplementation. However, aspartate aminotransferase (AST) showed a significant increase in healthy controls, while alanine aminotransferase (ALT) was significantly decreased in T2DM patients at 4 weeks (P <0.05), though values remained within the normal ranges. Among the biomarkers of lipid oxidation and inflammation, oxidized LDL and serum C-reactive protein (CRP) did not differ at 4 weeks in either group, while pomegranate polyphenols significantly decreased malondialdehyde (MDA) and hydroxynonenal (HNE) only in the diabetic group versus baseline (P <0.05). Conclusions. POMx reduces lipid peroxidation in patients with T2DM, but with no effects in healthy controls, and specifically modulates liver enzymes in diabetic and nondiabetic subjects. Larger clinical trials are merited.
Resumo:
Respiratory syncytial virus (RSV) is a major pathogen that primarily infects airway epithelium. Most infants suffer mild upper respiratory tract (URT) symptoms, while approximately one third progress to lower respiratory tract (LRT) involvement. Despite the ubiquity of URT infection, little is known about the relative cytopathogenesis of RSV infection in infant URT and LRT.
Resumo:
Background: The authors consider whether differences in stage at diagnosis could explain the variation in lung cancer survival between six developed countries in 2004-2007. Methods: Routinely collected population-based data were obtained on all adults (15-99 years) diagnosed with lung cancer in 2004-2007 and registered in regional and national cancer registries in Australia, Canada, Denmark, Norway, Sweden and the UK. Stage data for 57 352 patients were consolidated from various classification systems. Flexible parametric hazard models on the log cumulative scale were used to estimate net survival at 1 year and the excess hazard up to 18 months after diagnosis. Results: Age-standardised 1-year net survival from non-small cell lung cancer ranged from 30% (UK) to 46% (Sweden). Patients in the UK and Denmark had lower survival than elsewhere, partly because of a more adverse stage distribution. However, there were also wide international differences in stage-specific survival. Net survival from TNM stage I non-small cell lung cancer was 16% lower in the UK than in Sweden, and for TNM stage IV disease survival was 10% lower. Similar patterns were found for small cell lung cancer. Conclusions: There are comparability issues when using population-based data but, even given these constraints, this study shows that, while differences in stage at diagnosis explain some of the international variation in overall lung cancer survival, wide disparities in stage-specific survival exist, suggesting that other factors are also important such as differences in treatment. Stage should be included in international cancer survival studies and the comparability of population-based data should be improved.
Resumo:
Objective: We investigate what role stage at diagnosis bears in international differences in ovarian cancer survival. Methods: Data from population-based cancer registries in Australia, Canada, Denmark, Norway, and the UK were analysed for 20,073 women diagnosed with ovarian cancer during 2004-07. We compare the stage distribution between countries and estimate stage-specific one-year net survival and the excess hazard up to 18 months after diagnosis, using flexible parametric models on the log cumulative excess hazard scale. Results: One-year survival was 69% in the UK, 72% in Denmark and 74-75% elsewhere. In Denmark, 74% of patients were diagnosed with FIGO stages III-IV disease, compared to 60-70% elsewhere. International differences in survival were evident at each stage of disease; women in the UK had lower survival than in the other four countries for patients with FIGO stages III-IV disease (61.4% vs. 65.8-74.4%). International differences were widest for older women and for those with advanced stage or with no stage data. Conclusion: Differences in stage at diagnosis partly explain international variation in ovarian cancer survival, and a more adverse stage distribution contributes to comparatively low survival in Denmark. This could arise because of differences in tumour biology, staging procedures or diagnostic delay. Differences in survival also exist within each stage, as illustrated by lower survival for advanced disease in the UK, suggesting unequal access to optimal treatment. Population-based data on cancer survival by stage are vital for cancer surveillance, and global consensus is needed to make stage data in cancer registries more consistent. © 2012 Elsevier Inc.