Comparing predictions of extinction risk using models and subjective judgement

Models of population dynamics are commonly used to predict risks in ecology, particularly risks of population decline. There is often considerable uncertainty associated with these predictions. However, alternatives to predictions based on population models have not been assessed. We used simulation models of hypothetical species to generate the kinds of data that might typically be available to ecologists and then invited other researchers to predict risks of population declines using these data. The accuracy of the predictions was assessed by comparison with the forecasts of the original model. The researchers used either population models or subjective judgement to make their predictions. Predictions made using models were only slightly more accurate than subjective judgements of risk. However, predictions using models tended to be unbiased, while subjective judgements were biased towards over-estimation. Psychology literature suggests that the bias of subjective judgements is likely to vary somewhat unpredictably among people, depending on their stake in the outcome. This will make subjective predictions more uncertain and less transparent than those based on models. (C) 2004 Elsevier SAS. All rights reserved.

Serum triglycerides as a risk factor for cardiovascular diseases in the Asia-Pacific Region

Background-The importance of serum triglyceride levels as a risk factor for cardiovascular diseases is uncertain. Methods and Results-We performed an individual participant data meta-analysis of prospective studies conducted in the Asia-Pacific region. Cox models were applied to the combined data from 26 studies to estimate the overall and region-, sex-, and age-specific hazard ratios for major cardiovascular diseases by fifths of triglyceride values. During 796 671 person-years of follow-up among 96 224 individuals, 670 and 667 deaths as a result of coronary heart disease (CHD) and stroke, respectively, were recorded. After adjustment for major cardiovascular risk factors, participants grouped in the highest fifth of triglyceride levels had a 70% (95% CI, 47 to 96) greater risk of CHD death, an 80% (95% CI, 49 to 119) higher risk of fatal or nonfatal CHD, and a 50% (95% CI, 29% to 76%) increased risk of fatal or nonfatal stroke compared with those belonging to the lowest fifth. The association between triglycerides and CHD death was similar across subgroups defined by ethnicity, age, and sex. Conclusions-Serum triglycerides are an important and independent predictor of CHD and stroke risk in the Asia-Pacific region. These results may have clinical implications for cardiovascular risk prediction and the use of lipid-lowering therapy.

Prevalence of peripheral arterial disease: persistence of excess risk in former smokers

Objective: To determine the age-standardised prevalence of peripheral arterial disease (PAD) and associated risk factors, particularly smoking. Method: Design: Cross-sectional survey of a randomly selected population. Setting: Metropolitan area of Perth, Western Australia. Participants: Men aged between 65-83 years. Results: The adjusted response fraction was 77.2%. Of 4,470 men assessed, 744 were identified as having PAD by the Edinburgh Claudication Questionnaire and/or the ankle-brachial index of systolic blood pressure, yielding an age-standardised prevalence of PAD of 15.6% (95% confidence intervals (CI): 14.5%, 16.6%). The main risk factors identified in univariate analyses were increasing age, smoking current (OR=3.9, 95% CI 2.9-5.1) or former (OR=2.0, 95% CI 1.6-2.4), physical inactivity (OR=1.4, 95% CI 1.2-1.7), a history of angina (OR=2.2, 95% CI 1.8-2.7) and diabetes mellitus (OR=2.1, 95% CI 1.7-2.6). The multivariate analysis showed that the highest relative risk associated with PAD was current smoking of 25 or more cigarettes daily (OR=7.3, 95% CI 4.2-12.8). In this population, 32% of PAD was attributable to current smoking and a further 40% was attributable to past smoking by men who did not smoke currently. Conclusions: This large observational study shows that PAD is relatively common in older, urban Australian men. In contrast with its relationship to coronary disease and stroke, previous smoking appears to have a long legacy of increased risk of PAD. Implications: This research emphasises the importance of smoking as a preventable cause of PAD.

Decline in homicide rates in Sao Paulo, Brasil: a descriptive analysis

Objective. To describe homicide mortality in the municipality of Sao Paulo according to type of weapon, sex, race or skin color, age, and areas of socioeconomic inequalities, between 1996 and 2008. Method. For this ecological time-series study, data about deaths in the municipality of Sao Paulo were collected from the municipal program for improvement of mortality information, using International Classification of Diseases, 10th revision (ICD-10) codes. Homicide mortality rates (HMR) were calculated for the overall population and specifically for each sex, race or skin color, age range, type of weapon, and occurrence in social deprivation/affluence areas. HMR were adjusted for age using the direct method. The percentage age of variation in HMR was calculated for the study period. For areas of socioeconomic inequalities, the relative risk of death from homicide was calculated. Results. HMR fell 73.7% between 2001 and 2008. A reduction in HMR was observed in all groups, especially males (-74.5%), young men between 15 and 24 years of age (-78.0%), and residents in areas of extreme socioeconomic deprivation (-79.3%). The reduction occurred mostly in firearm homicide rates (-74.1%). The relative risk of death from homicide in areas of extreme socioeconomic deprivation, as compared to areas with some degree of socioeconomic deprivation, was 2.77 in 1996, 3.9 in 2001, and 2.13 in 2008. In areas of high socioeconomic deprivation, the relative risk was 2.07 in 1996 and 1.96 in 2008. Conclusions. To understand the reduction in homicide rates in the municipality of Sao Paulo, it is important to take into consideration macrodeterminants that affect the entire municipality and all population subgroups, as well as micro/local determinants that have special impact on homicides committed with firearms and on subgroups such as the young, males, and residents of areas of high socioeconomic deprivation.

Constipation in intensive care unit: Incidence and risk factors

Purpose: Although gastrointestinal motility disorders are common in critically ill patients, constipation and its implications have received very little attention. We aimed to determine the incidence of constipation to find risk factors and its implications in critically ill patients Materials and Methods: During a 6-month period, we enrolled all patients admitted to an intensive care unit from an universitary hospital who stayed 3 or more days. Patients submitted to bowel surgery were excluded. Results: Constipation occurred in 69.9% of the patients. There was no difference between constipated and not constipated in terms of sex, age, Acute Physiology and Chronic Health Evaluation II, type of admission (surgical, clinical, or trauma), opiate use, antibiotic therapy, and mechanical ventilation. Early (<24 hours) enteral nutrition was associated with less constipation, a finding that persisted at multivariable analysis (P < .01). Constipation was not associated with greater intensive care unit or mortality, length of stay, or days free from mechanical ventilation. Conclusions: Constipation is very common among critically ill patients. Early enteral nutrition is associated with earlier return of bowel function. (C) 2009 Elsevier Inc. All rights reserved.

Endomyocardial Biopsy as Risk Factor in the Development of Tricuspid Insufficiency After Heart Transplantation

Objective. Endomyocardial biopsy (EMB), which is used to monitor for rejection, may cause tricuspid regurgitation (TR) after orthotopic heart transplantation (OHT). The purpose of this investigation was to examine the occurrence of tricuspid valve tissue in myocardial specimens obtained by routine EMB performed after OHT. Patients and Methods. From January 2000 to July 2008, 125 of the patients who underwent OHT survived more than I month. Their follow-up varied from I month to 8.5 years (mean, 5.1 +/- 3.7 years). EMB was the gold standard examination and myocardial scintigraphy with gallium served as a screen to routinely monitor rejection. Results. Each of 428 EMB including 4 to 7 fragments, totaling 1715 fragments, were reviewed for this study. The number of EMB per patient varied from 3 to 8 (mean, 4.6 +/- 3.5). Histopathological analysis of these fragments showed tricuspid tissue in 4 patients (3.2%), among whom only I showed aggravation of TR. Conclusions. EMB remains the standard method to diagnose rejection after OLT. It can be performed with low risk. Reducing the number of EMB using gallium myocardial scintigraphy or other alternative methods as well as adoption of special care during the biopsy can significantly minimize trauma to the tricuspid valve.

Long-term safety and efficacy of percutaneous coronary intervention with stenting and coronary artery bypass surgery for multivessel coronary artery disease - A meta-analysis with 5-year patient-level data from the ARTS, ERACI-II, MASS-II, and SoS trials

Background-Randomized trials that studied clinical outcomes after percutaneous coronary intervention (PCI) with bare metal stenting versus coronary artery bypass grafting (CABG) are underpowered to properly assess safety end points like death, stroke, and myocardial infarction. Pooling data from randomized controlled trials increases the statistical power and allows better assessment of the treatment effect in high-risk subgroups. Methods and Results-We performed a pooled analysis of 3051 patients in 4 randomized trials evaluating the relative safety and efficacy of PCI with stenting and CABG at 5 years for the treatment of multivessel coronary artery disease. The primary end point was the composite end point of death, stroke, or myocardial infarction. The secondary end point was the occurrence of major adverse cardiac and cerebrovascular accidents, death, stroke, myocardial infarction, and repeat revascularization. We tested for heterogeneities in treatment effect in patient subgroups. At 5 years, the cumulative incidence of death, myocardial infarction, and stroke was similar in patients randomized to PCI with stenting versus CABG (16.7% versus 16.9%, respectively; hazard ratio, 1.04, 95% confidence interval, 0.86 to 1.27; P = 0.69). Repeat revascularization, however, occurred significantly more frequently after PCI than CABG (29.0% versus 7.9%, respectively; hazard ratio, 0.23; 95% confidence interval, 0.18 to 0.29; P<0.001). Major adverse cardiac and cerebrovascular events were significantly higher in the PCI than the CABG group (39.2% versus 23.0%, respectively; hazard ratio, 0.53; 95% confidence interval, 0.45 to 0.61; P<0.001). No heterogeneity of treatment effect was found in the subgroups, including diabetic patients and those presenting with 3-vessel disease. Conclusions-In this pooled analysis of 4 randomized trials, PCI with stenting was associated with a long-term safety profile similar to that of CABG. However, as a result of persistently lower repeat revascularization rates in the CABG patients, overall major adverse cardiac and cerebrovascular event rates were significantly lower in the CABG group at 5 years.

Real-time detection of pneumothorax using electrical impedance tomogyaphy

Objectives: Pneumothorax is a frequent complication during mechanical ventilation. Electrical impedance tomography (EIT) is a noninvasive tool that allows real-time imaging of regional ventilation. The purpose of this study was to 1) identify characteristic changes in the EIT signals associated with pneumothoraces; 2) develop and fine-tune an algorithm for their automatic detection; and 3) prospectively evaluate this algorithm for its sensitivity and specificity in detecting pneumothoraces in real time. Design: Prospective controlled laboratory animal investigation. Setting: Experimental Pulmonology Laboratory of the University of Sao Paulo. Subjects: Thirty-nine anesthetized mechanically ventilated supine pigs (31.0 +/- 3.2 kg, mean +/- SD). Interventions. In a first group of 18 animals monitored by EIT, we either injected progressive amounts of air (from 20 to 500 mL) through chest tubes or applied large positive end-expiratory pressure (PEEP) increments to simulate extreme lung overdistension. This first data set was used to calibrate an EIT-based pneumothorax detection algorithm. Subsequently, we evaluated the real-time performance of the detection algorithm in 21 additional animals (with normal or preinjured lungs), submitted to multiple ventilatory interventions or traumatic punctures of the lung. Measurements and Main Results: Primary EIT relative images were acquired online (50 images/sec) and processed according to a few imaging-analysis routines running automatically and in parallel. Pneumothoraces as small as 20 mL could be detected with a sensitivity of 100% and specificity 95% and could be easily distinguished from parenchymal overdistension induced by PEEP or recruiting maneuvers, Their location was correctly identified in all cases, with a total delay of only three respiratory cycles. Conclusions. We created an EIT-based algorithm capable of detecting early signs of pneumothoraces in high-risk situations, which also identifies its location. It requires that the pneumothorax occurs or enlarges at least minimally during the monitoring period. Such detection was operator-free and in quasi real-time, opening opportunities for improving patient safety during mechanical ventilation.

Immunohistochemical analysis of p53, APE1, hMSH2 and ERCC1 proteins in actinic cheilitis and lip squamous cell carcinoma

Aims: This study has compared the tissue expression of the p53 tumour suppressor protein and DNA repair proteins APE1, hMSH2 and ERCC1 in normal, dysplastic and malignant lip epithelium. Methods and results: Morphological analysis and immunohistochemistry were performed on archived specimens of normal lip mucosa (n = 15), actinic cheilitis (AC) (n = 30), and lip squamous cell carcinoma (LSCC) (n = 27). AC samples were classified morphologically according to the severity of epithelial dysplasia and risk of malignant transformation. LSCC samples were morphologically staged according to WHO and invasive front grading (IFG) criteria. Differences between groups and morphological stages were determined by bivariate statistical analysis. Progressive increases in the percentage of epithelial cells expressing p53 and APE1 were associated with increases in morphological malignancy from normal lip mucosa to LSCC. There was also a significant reduction in epithelial cells expressing hMSH2 and ERCC1 proteins in the AC and LSCC groups. A higher percentage of malignant cells expressing APE1 was found in samples with an aggressive morphological IFG grade. Conclusions: Our data showed that epithelial cells from premalignant to malignant lip disease exhibited changes in the expression of p53, APE1, hMSH2 and ERCC1 proteins; these molecular change might contribute to lip carcinogenesis.

Thirty-Day Morbidity and Mortality of the Laparoscopic Ileal Interposition Associated with Sleeve Gastrectomy for the Treatment of Type 2 Diabetic Patients with BMI < 35: An Analysis of 454 Consecutive Patients

Background The objective of this study was to evaluate the early results of the laparoscopic interposition of a segment of ileum associated with a sleeve gastrectomy (LII-SG) in order to treat patients with type 2 diabetes mellitus (T2DM) and BMI <35. Data regarding morbidly obese diabetic patients subjected to surgery has consistently been validated. To date, there is scarce information about morbidity and mortality related to the surgical treatment of a ""true"" typical diabetic population with BMI <35. Methods The procedures were performed in 454 patients (322 male, 132 female). Mean age was 53.6 +/- 8 years (range = 27-75). Mean BMI was 29.7 +/- 3.6 kg/m(2) (range = 19-34.8). All patients had the diagnosis of T2DM for at least 3 years. Insulin therapy was used by 45.6% of patients. Mean duration of T2DM was 10.8 +/- 5.9 years (range = 3-35). Mean hemoglobin A(1c) was 8.8 +/- 1.9%. Dyslipidemia was observed in 78.4%, hypertension in 64.8%, nephropathy in 28.6%, retinopathy in 32.6%, neuropathy in 34.6%, and coronary heart disease in 13%. Results There was no conversion to open surgery. All patients were evaluated postoperatively. Mortality was 0.4%. There were 29 major complications (6.4%) in 22 patients (4.8%) and 51 minor complications (11.2%). Reoperations were performed on 8 patients (1.7%). Twenty patients (4.4%) were readmitted to the hospital. Mean postoperative BMI was 25.8 +/- 3.5 kg/m(2). Mean fasting plasma glucose decreased from 198 +/- 69 to 128 +/- 67 mg/dl and mean postprandial plasma glucose decreased from 262 +/- 101 to 136 +/- 43 mg/dl. Conclusions The laparoscopic ileal interposition associated with a sleeve gastrectomy was considered a safe operation with low rates of morbidity and mortality in a diabetic population with BMI < 35. An early control of postprandial glycemia was observed.

An analysis of valve re-replacement after aortic valve replacement with biologic devices

Biologic valve re-replacement was examined in a series of 1343 patients who underwent aortic valve replacement at The Prince Charles Hospital, Brisbane, with a cryopreserved or 4 degrees C stored allograft valve or a xenograft valve, A parametric model approach was used to simultaneously model the competing risks of death without re-replacement and re-replacement before death, One hundred eleven patients underwent a first re-replacement for a variety of reasons (69 patients with xenograft valves, 28 patients with 4 degrees C stored allograft valves, and 14 patients with cryopreserved allograft valves), By multivariable analysis younger age at operation was associated with xenograft, 4 degrees C stored allograft, and cryopreserved allograft valve re-replacement, However, this effect was examined in the context of longer survival of younger patients, which increases their exposure to the risk of re-replacement as compared with that in older patients whose decreased survival reduced their probability of requiring valve re-replacement, In patients older than 60 years at the time of aortic valve replacement, the probability of re-replacement (for any reason) before death was similar for xenografts and cryopreserved allograft valves but higher for 4 degrees C stored valves, However, in patients younger than 60 years, the probability of re-replacement at any time during the remainder of the life of the patient was lower with the cryopreserved allograft valve compared with the xenograft valve and 4 degrees C stored allografts.

Risk factors for sudden unexpected cardiac death in Tasmanian men

Background: Sudden unexpected cardiac death (SUCD) accounts for approximately 25% of deaths from ischaemic heart disease (IHD) but is relatively poorly understood because of the difficulties involved in researching aetiology. Clinical differences between instances of SUCD and those cases of acute chest pain that survive long enough to be proven as myocardial infarction but are eventually fatal might reflect differences in aetiology. Aims: To determine the risk factors for sudden unexpected cardiac death in Tasmanian men. Methods: A population-based case-control method was used with the study population, an estimated 125,225 men aged 25-74 years living in the island State of Tasmania, Australia. The case group of 102 men who had a SUCD was validated using necropsy reports, hospital records and information provided by the usual general practitioner. Cases were matched with 204 community controls. Spouses or partners of eligible subjects answered a detailed questionnaire. Multi-variate odds ratios (ORs) for risk factors were calculated using stepwise analysis. Results: Risk factors measured included: smoking habit, treated hypertension, hypercholesterolaemia, diabetes mellitus, family history of LHD, alcohol intake and exercise habits. Independent risk factors for SUCD were: history of diabetes mellitus (OR=4.2, 95% CI: 1.39, 12.81), current smoking status (OR=3.5, 95% CI: 1.80, 6.82), and family history of IHD (OR=2.6, 95% CI: 1.34, 4.92). Conclusions: Some accepted risk factors for acute myocardial infarction (AMI) also predict sudden death in men with no history of coronary disease. Efforts to reduce smoking, the incidence of diabetes mellitus and mean blood pressure must be continued as SUCD is, by definition, untreatable but is potentially avoidable in many instances.

Heterozygosity for the S180L Variant of MAL/TIRAP, a Gene Expressing an Adaptor Protein in the Toll-Like Receptor Pathway, Is Associated with Lower Risk of Developing Chronic Chagas Cardiomyopathy

Background. Chagas disease is caused by the protozoan parasite Trypanosoma cruzi. Among T. cruzi-infected individuals, only a subgroup develops severe chronic Chagas cardiomyopathy (CCC); the majority remain asymptomatic. T. cruzi displays numerous ligands for the Toll-like receptors (TLRs), which are an important component of innate immunity that lead to the transcription of proinflammatory cytokines by nuclear factor-kappa B. Because proinflammatory cytokines play an important role in CCC, we hypothesized that single-nucleotide polymorphisms (SNPs) in the genes that encode proteins in the TLR pathway could explain differential susceptibility to CCC among T. cruzi-infected individuals. Methods. For 169 patients with CCC and 76 T. cruzi-infected, asymptomatic individuals, we analyzed SNPs by use of polymerase chain reaction-restriction fragment length polymorphism analysis for the genes TLR1, TLR2, TLR4, TLR5, TLR9, and MAL/TIRAP, which encodes an adaptor protein. Results. Heterozygous carriers of the MAL/TIRAP variant S180L were more prevalent in the asymptomatic group (24 [32%] of 76 subjects) than in the CCC group (21 [12%] of 169) (chi(2) = 12.6; P = .0004 [adjusted P (P(c)) = .0084]; odds ratio [OR], 0.31 [95% confidence interval {CI}, 0.16-0.60]). Subgroup analysis showed a stronger association when asymptomatic patients were compared with patients who had severe CCC (i.e., patients with left-ventricular ejection fraction <= 40%) (chi(2) = 11.3; P = .0008 [P(c) = .017]; OR, 0.22 [95% CI, 0.09-0.56]) than when asymptomatic patients were compared with patients who had mild CCC (i.e., patients with left-ventricular ejection fraction >40%) (chi(2) = 7.7; P = .005 [P(c) = .11]; OR, 0.33 [95% CI, 0.15-0.73]). Conclusion. T. cruzi-infected individuals who are heterozygous for the MAL/TIRAP S180L variant that leads to a decrease in signal transduction upon ligation of TLR2 or TLR4 to their respective ligand may have a lower risk of developing CCC.

p63 Protein expression in high risk diffuse large B-cell lymphoma

Background: p63 gene is a p53 homologue that encodes proteins with transactivation, DNA-binding and tetramerisation domains. The isoforms TAp63 and TAp73 transactivate p53 target genes and induce apoptosis, whereas the isoforms Delta Np63 and Delta Np73 lack transactivation and might have dominant-negative effects in p53 family members. p63 is expressed in germinal centre lymphocytes and can be related to the development of the lymphoma, but the prognostic significance of its expression in the survival of patients with diffuse large B-cell lymphoma (DLBCL) remains unclear. Aims: To determine whether quantitative immunohistochemical (IHC) analysis of p63 protein expression correlates with CD10 antigen, Bcl-6 antigen and IRF4 antigen expression and to determine whether p63 is a surrogate predictor of overall survival in high-intermediate and high risk DLBCL populations. Methods: CD10, Bcl-6 and IRF4 expression were retrospectively evaluated by IHC in 73 samples of high intermediate and high risk DLBCL and were used to divide the lymphomas into subgroups of germinal centre B-celllike (GCB) and activate B-cell-like (ABC) DLBCL. Similarly, p63 expression was evaluated by IHC and the results were compared with subgroups of DLBCL origin and with the survival rates for these patients. Results: p63 was expressed in more than 50% of malignant cells in 11 patients and did not show correlation with subgroups of GCB-like DLBCL or ABC-like DLBCL, but p63(+) patients had better disease-free survival (DFS) than those who were negative (p = 0.01). Conclusions: p63(+) high-intermediate and high risk DLBCL patients have a better DFS than negative cases.