Modelling the Distribution of Ischaemic Stroke-Specific Survival Time Using an EM-based Mixture Approach with Random Effects Adjustment

A two-component survival mixture model is proposed to analyse a set of ischaemic stroke-specific mortality data. The survival experience of stroke patients after index stroke may be described by a subpopulation of patients in the acute condition and another subpopulation of patients in the chronic phase. To adjust for the inherent correlation of observations due to random hospital effects, a mixture model of two survival functions with random effects is formulated. Assuming a Weibull hazard in both components, an EM algorithm is developed for the estimation of fixed effect parameters and variance components. A simulation study is conducted to assess the performance of the two-component survival mixture model estimators. Simulation results confirm the applicability of the proposed model in a small sample setting. Copyright (C) 2004 John Wiley Sons, Ltd.

Homocysteine-lowering treatment with folic acid, cobalamin, and pyridoxine does not reduce blood markers of inflammation, endothelial dysfunction, or hypercoagulability in patients with previous transient ischemic attack or stroke - a randomized substudy

Background and Purpose - Epidemiological and laboratory studies suggest that increasing concentrations of plasma homocysteine ( total homocysteine [tHcy]) accelerate cardiovascular disease by promoting vascular inflammation, endothelial dysfunction, and hypercoagulability. Methods - We conducted a randomized controlled trial in 285 patients with recent transient ischemic attack or stroke to examine the effect of lowering tHcy with folic acid 2 mg, vitamin B-12 0.5 mg, and vitamin B-6 25 mg compared with placebo on laboratory markers of vascular inflammation, endothelial dysfunction, and hypercoagulability. Results - At 6 months after randomization, there was no significant difference in blood concentrations of markers of vascular inflammation (high-sensitivity C-reactive protein [P = 0.32]; soluble CD40L [ P = 0.33]; IL-6 [P = 0.77]), endothelial dysfunction ( vascular cell adhesion molecule-1 [P = 0.27]; intercellular adhesion molecule-1 [P = 0.08]; von Willebrand factor [P = 0.92]), and hypercoagulability (P-selectin [P = 0.33]; prothrombin fragment 1 and 2 [P = 0.81]; D-dimer [P = 0.88]) among patients assigned vitamin therapy compared with placebo despite a 3.7-mumol/L (95% CI, 2.7 to 4.7) reduction in total homocysteine (tHcy). Conclusions - Lowering tHcy by 3.7 mumol/L with folic acid-based multivitamin therapy does not significantly reduce blood concentrations of the biomarkers of inflammation, endothelial dysfunction, or hypercoagulability measured in our study. The possible explanations for our findings are: ( 1) these biomarkers are not sensitive to the effects of lowering tHcy (eg, multiple risk factor interventions may be required); ( 2) elevated tHcy causes cardiovascular disease by mechanisms other than the biomarkers measured; or ( 3) elevated tHcy is a noncausal marker of increased vascular risk.

Trends in five-year survival and risk of recurrent stroke after first-ever stroke in the Perth community stroke study

Background: Few studies provide information on trends in the long-term outcome of stroke. We aimed to determine trends in survival and recurrent stroke, over 5 years after first-ever stroke, for 2 cohorts of patients enrolled in the Perth Community Stroke Study in 1989 90 and 1995-96. Methods: For 12-month periods beginning February 1989 and February 1995, all individuals with an acute stroke who were resident in a geographically-defined and representative region of Perth, Western Australia, were registered and followed-up prospectively 5 years after the index event. Results: The 5-year cumulative risk of death was 59% (95% confidence interval (CI) 53%, 65%) and 58% (95% CI 52%, 65%) for the 1989-90 and 1995-96 cohorts, respectively (p = 0.94). The 5-year cumulative risk of first recurrent stroke was 32% (95% CI 25%, 40%) and 23% (95% CI 16%, 30%) for the 1989-90 and 1995-96 cohorts, respectively (p = 0.07). Conclusions: Although no statistically significant improvement occurred in 5-year survival after first-ever stroke in Perth between 1989-90 and 1995-96, there was a statistically nonsignificant trend towards a smaller cumulative risk of recurrent stroke over 5 years after a first-ever stroke. Serial community-based studies of the incidence and outcome of stroke are an important means of monitoring the translation of proven preventive interventions to improvements in population health. Copyright (C) 2005 S. Karger AG, Basel.

Redescription of Riethia truncatocaudata (Edwards, 1931) (Diptera: Chironomidae), with description of female, pupa and larva and generic diagnosis for Riethia

The discovery of the immature life history stages of Riethia truncatocaudata (Edwards, 1931) from South America allows diagnosis of Riethia Kieffer, 1917 in all stages, incorporating reared species from the complete austral range. Pseudochironomus truncatocaudata Edwards, 1931 is a senior synonym (syn. n.) of Pseudochironomus melanoides Edwards, 1931. We redescribe the male to complement the short original descriptions of R. truncatocaudata and R. melanoides. The species is congeneric with Australian Riethia stictoptera Kieffer, the type species of the genus Riethia. Extensive material available from the western Pacific (Australia, New Zealand and New Caledonia) confirms that the diagnosis extends to a gondwanan clade, likely sister group to the largely northern genus Pseudochironomus Kieffer.

Study of acetylcholinesterase activity in rectal suction biopsy for diagnosis of intestinal dysganglionoses: 17-year experience of a single center

Although the utility of the acetylcholinesterase (AChE) histochemistry on rectal suction biopsy in diagnosing Hirschsprung`s disease (HD) has been documented, few reports address a great number of biopsies and patients. Our aim is to present a 17-year experience on the method of rectal suction biopsy and AChE histochemical staining for diagnosis of intestinal dysganglionoses. Between August 1989 and July 2006, 297 children suspected of having HD were submitted to rectal suction biopsies that were evaluated by the same two surgeons. There were 18 complications (6.0%), namely one self-limited rectal bleeding and 17 (5.7%) inadequate procedures that were repeated. A total of 157 patients (52.8%) showed no increased AChE activity and the remaining patients (140-47.2.0%) presented patterns of increased AChE activity confirming the diagnosis of HD or neuronal intestinal dysplasia. Among the 140 cases suspected as having HD, in 131 children the diagnosis of HD was confirmed and they were operated on. The histological studies showed that 111 children presented the classic form of HD or a long spastic segment. Sixteen children presented total colonic aganglionosis and four children proved to have intestinal neuronal dysplasia, according to histological and radiological criteria. Nine (6.6%) newborns were identified as false-positives and no false-negative results were verified. The rectal suction biopsy combined with AChE staining is advantageous for the differentiation between normal bowel and intestinal dysganglionoses. The rectal suction method is simple and can easily be performed by experienced surgeons. The histological evaluation is very objective and can be performed by a non-pathologist.

Improving Alzheimer`s Disease Diagnosis with Machine Learning Techniques

There is not a specific test to diagnose Alzheimer`s disease (AD). Its diagnosis should be based upon clinical history, neuropsychological and laboratory tests, neuroimaging and electroencephalography (EEG). Therefore, new approaches are necessary to enable earlier and more accurate diagnosis and to follow treatment results. In this study we used a Machine Learning (ML) technique, named Support Vector Machine (SVM), to search patterns in EEG epochs to differentiate AD patients from controls. As a result, we developed a quantitative EEG (qEEG) processing method for automatic differentiation of patients with AD from normal individuals, as a complement to the diagnosis of probable dementia. We studied EEGs from 19 normal subjects (14 females/5 males, mean age 71.6 years) and 16 probable mild to moderate symptoms AD patients (14 females/2 males, mean age 73.4 years. The results obtained from analysis of EEG epochs were accuracy 79.9% and sensitivity 83.2%. The analysis considering the diagnosis of each individual patient reached 87.0% accuracy and 91.7% sensitivity.

Fibromyalgia in primary antiphospholipid (Hughes) syndrome

Fibromyalgia (FM) is a syndrome that can be associated with several rheumatic diseases. However, no study has evaluated its frequency in patients with primary antiphospholipid syndrome (PAPS). The objective of this study was to analyze the frequency of FM in PAPS patients compared with healthy controls, to determine the possible associations between FM and PAPS features, and also to evaluate quality of life and depression in these patients. This case-control study included 30 PAPS patients (by the Sapporo criteria) and 40 healthy subjects. Demographic and clinical data, drug use, and antiphospholipid antibodies were analyzed. FM was diagnosed based on international criteria (ACR). Questionnaires on quality of life, including the Short Form 36 Health Survey (SF-36), Beck Depression Inventory (BDI), Fibromyalgia Impact Questionnaire (FIQ), and Visual Analog Scale (VAS), were also applied. PAPS patients and controls were similar in mean age as well as in distributions of gender and Caucasian race. Mean disease duration was 5.4 +/- 4.2 years. A diagnosis of fibromyalgia was made in five (16.7%) PAPS patients and no controls (p = 0.012). PAPS patients had more diffuse pain (53% vs. 0%, respectively, p<0.0001), >= 11 tender points (23% vs. 5%, respectively, p = 0.032), and a greater total number (175 vs. 57, respectively, p<0.0001) as well as median number of tender points per patient than controls (5 [0-18] vs. 0 [0-11], respectively, p<0.0001). PAPS patients had lower values in all dimensions of the SF-36, as well as higher FIQ scores, higher BDI scores, more depression diagnoses according to BDI results, and increased VAS in comparison with controls. Analysis of PAPS patients with FM compared with those subjects without FM revealed no significant differences regarding demographic features or thrombotic or clinical events; however, PAPS patients who also had FM had lower values in SF-36 dimensions as well as higher FIQ (82.6 +/- 9.6 vs. 33.6 +/- 29.8, respectively, p<0.0001) and VAS scores (6.6 +/- 2.97 vs. 3.25 +/- 3.11, respectively, p = 0.03). BDI scores, in contrast, were similar in both groups. In conclusion, one-fifth of PAPS patients had fibromyalgia and a low quality of life when compared with healthy subjects. Lupus (2011) 20, 1182-1186.

Alcohol use disorders in patients with obsessive-compulsive disorder: The importance of appropriate dual-diagnosis

Objective: To evaluate the prevalence and clinical associated factors of alcohol use disorders (AUD) comorbidity in a large clinical sample of patients with obsessive-compulsive disorder (OCD). Methods: A cross-sectional study including 630 DSM-IV OCD patients from seven Brazilian university services, comparing patients with and without AUD comorbidity. The instruments of assessment used were a demographic and clinical questionnaire including evaluation of suicidal thoughts and acts and psychiatric treatment, the Structured Clinical Interview for DSM-IV Axis I disorders (SCID-I), the Yale-Brown Obsessive-Compulsive Scale, the Dimensional Yale-Brown Obsessive-Compulsive Scale, the Brown Assessment of Beliefs Scale, the Beck Depression and Anxiety Inventories and the Clinical Global Impression Scale. Current or past alcohol and other psychoactive substances use, abuse and dependence were assessed using the SCID-I (section E) and corroborated by medical and familial history questionnaires. Results: Forty-seven patients (7.5%) presented AUD comorbidity. Compared to OCD patients without this comorbidity they were more likely to be men, to have received previous psychiatric treatment, to present: lifetime suicidal thoughts and attempts and to have higher scores in the hoarding dimension. They also presented higher comorbidity with generalized anxiety and somatization disorders, and compulsive sexual behavior. Substance use was related to the appearance of the first O.C. symptoms and symptom amelioration. Conclusions: Although uncommon among OCD treatment seeking samples, AUD comorbidity has specific clinical features, such as increased risk for suicidality, which deserve special attention from mental health professionals. Future studies focused on the development of specific interventions for these patients are warranted. (C) 2008 Elsevier Ireland Ltd. All rights reserved.

The Use of Smell Identification Tests in the Diagnosis of Parkinson`s Disease in Brazil

Smell identification tests may be of routine clinical value in the differential diagnosis of PD but are subject to cultural variation and have not been systematically evaluated in the Brazilian population. We have applied culturally adapted translations of the University of Pennsylvania 40-item smell identification test (UPSIT-40) and the 16-item identification test from Sniffin` Sticks (SS-16) to nondemented Brazilian PD patients and controls. Pearson`s correlation coefficient between the test scores was 0.76 (95% CI 0.70-0.81, n = 204, P < 0.001). To calculate reliability measures for each test we used the diagnosis (either PD or control) as outcome variable for separate logistic regression analyses using the score in the UPSIT-40 or the SS-16 as a covariate. The SS-16 specificity was 89.0% with a sensitivity of 81.1% (106 PD and 118 controls). The UPSIT-40 specificity was 83.5% and its sensitivity 82.1% (95 PD and 109 controls). Regression curves were used to associate an individual`s smell test score with the probability of belonging to the PD, as opposed to the control group. Our data provide support for the use of the UPSIT-40 and SS-16 to help distinguish early PD from controls. (c) 2008 Movement Disorder Society

Primary antiphospholipid syndrome with and without Sneddon`s syndrome

The main objective of this study was to compare clinical and laboratory data obtained from patients with primary antiphospholipid syndrome (PAPS) with and without Sneddon`s syndrome (SS). A transverse study with 54 (85.2% female) PAPS patients (Sapporo criteria) was performed. Demographic, drug use, and antiphospholipid antibodies data were evaluated, as well as clinical and laboratory findings of SS. Patients were subdivided into one of two groups: PAPS with SS and PAPS without SS. Both groups were similar with respect to age (p = 0.05), gender (p = 0.34), race (p = 0.31), weight (p = 0.93), height (p = 0.27), and body mass index (p = 0.75); however, the SS group exhibited higher disease duration (96.0 +/- A 54.9 vs. 55.2 +/- A 52.0 months, p = 0.01). By definition, all PAPS with SS patients suffer from stroke, an arterial event; the frequency of stroke events (28.5 vs. 7.5%, p = 0.04), as well as of limb ischemia (100 vs. 30.0%, p < 0.0001) was higher in this group than in the PAPS without SS group. On the other hand, patients in the PAPS without SS group had more venous events, such as deep venous thrombosis, than those in the PAPS with SS group (80.0 vs. 50.0%, p = 0.03). In conclusion, an understanding of the relationship between APS and SS is important in order to identify a subgroup for which more rigorous accompaniment and therapy may be necessary.