Supported and unsupported claims in medicinal drug advertisements in Indian medical journals

The study assessed 292 supported and unsupported claims in 102 medicinal drug advertisements across 15 Indian medical journals published in 2009. WHO ethical criteria for medicinal drug promotion were applied. None of the advertisements satisfied all the WHO criteria. Safe prescribing information on major adverse drug reactions, contraindications and warnings was provided in only 19 advertisements. Of 292 drug claims, only 80 (27%) were supported with reference(s), of which only 7 (9%) claims were unambiguous, or well substantiated with references. 14 references quoted did not substantiate the claim and 15 constituted weak scientific evidence. Superlatives like "tested" "trusted" "guarantees success" and "matchless safety" were used without evidence to substantiate such claims. Stronger enforcement mechanisms are necessary to ensure reliable drug information in pharmaceutical advertisements.     

Volume Reconstruction Techniques Improve the Correlation Between Histological and in vivo Tumor Volume Measurements in Mouse Models of Human Gliomas

Assessment of therapy efficacy using animal models of tumorigenic cancer requires the ability to accurately measure changes in tumor volume over the duration of disease course. In order to be meaningful, in vivo tumor volume measurements by non-invasive techniques must correlate with tumor volume measurements from endpoint histological analysis. Tumor volume is frequently assessed by endpoint histological analyses approximating the tumor volume with geometric primitives such as spheroids and ellipsoids. In this study we investigated alternative techniques for quantifying histological volume measurements of tumors in a xenograft orthotopic mouse model of human glioblastoma multiforme, and compared these to in vivo tumor volume measurements based on magnetic resonance imaging (MRI) data. Two techniques leveraging three-dimensional (3D) image analysis methods were investigated. The first technique involves the reconstruction of a smoothed polygonal model representing the tumor volume from histological section images and is intended for accuracy and qualitative assessment of tumor burden by visualization, while a second technique which approximates the tumor volume as a series of slabs is presented as an abbreviated process intended to produce quantitatively similar volume measurements with a minimum of effort required on behalf of the investigator. New software (QuickVol) designed for use in the first technique, is also discussed. In cases where tumor growth is asymmetric and invasive, we found that 3D analysis techniques using histological section images produced volume measurements more consistent with in vivo volume measurements based on MRI data, than approximation of tumor volume using geometric primitives. Visualizations of the volumes represented by each of these techniques qualitatively support this finding, and suggest that future research using mouse models of glioblastoma multiforme (genetically engineered or xenograft) will benefit from the use of these or similar alternative tumor volume measurement techniques.     

Polymer-cosolvent systems, 1. Polystyrene in acetone/cyclohexane mixtures

Attempts were made to explain the cosolvency or the solubilisation of polystyrene in cyclohexane/acetone mixtures at 30°C. Cyclohexane is a Φ-solvent for polystyrene at 35°C. and acetone is a non-solvent. The effective interaction parameter χ_ms of Scott has been determined for the optimum solvent composition from the slope of a Stockmayer-Fixman plot as modified by Yamakawa. The value of unperturbed dimension obtained for polystyrene at this solvent composition coincides very well with that obtained in cyclohexane (Θ-solvent). The binary interaction parameter χ₁₂, between the two liquids obtained from χ_ms shows a certain amount of incompatibility between them. The values of λ^*, the preferential adsorption coefficient, were calculated for the entire solvent spectrum assuming the binary interaction parameters χ_ij as being independent of solvent composition. The inversion point (λ^* = 0), the optimum solvent composition yielding [η]_max, and the importance of χ₁₂₃, the ternary interaction parameter, are discussed.     

Prevalence and predictors of metabolic syndrome in non-obese Asian Indians with newly detected type 2 diabetes mellitus

We measured the prevalence and have evaluated the sensitivity, specificity, positive and negative predictive value of different predictors according to different standard criteria for metabolic syndrome in non-obese newly detected type 2 diabetes. Two hundred and fifteen patients of BMI <25 kg/m2 were studied. Metabolic syndrome prevalence was high in non-obese newly detected type 2 diabetes mellitus individuals. Greater prevalence of metabolic syndrome was observed in modified WHO (50.23%) and lesser in IDF (30.69%) classification. Non-obese metabolic syndrome individuals display significantly higher BMI, per cent body fat, waist circumference, hip circumference, waist hip ratio, blood pressure, triglyceride and a lower high density lipopratein than non-obese individuals without metabolic syndrome. The cut-off point for waist circumference in men was 86 cm and 79.7 cm for women (modified ATP III). Elevated serum triglyceride for men and low serum high density lipoprotein in women were the strongest predictors that effectively indicated the presence of metabolic syndrome in non-obese individuals.     

Validation of recall of body weight over a 26-year period in cohort members of the Adventist Health Study 2

PurposeThe validity of recall of past body weight has been measured and tends to be high; however, the paucity of validation data for recall in older age is noteworthy given the need for accounting for age and disease-related weight change in prospective studies.MethodsThe Adventist Health Study-2 (AHS-2) is a prospective, questionnaire-based study (n = 96,710) that enrolled a cohort from 2002 through 2007 to investigate the role of lifestyle exposures (diet, physical activity, anthropometrics) and health on outcomes such as cancer and mortality.ResultsThe mean difference between current weight reported 26 years earlier in AHS-1 and recall of past body weight in AHS-2 was only 0.67 kg, indicating underestimation in the recall of past body weight from ages 30 to 70 years.ConclusionsMisclassification is differential across both age and adiposity, and this tendency needs to be incorporated into the interpretation of weight history and health outcome literature.     

Paradoxical Hemodynamic Instability Complicating Pericardial Window Surgery for Cardiac Tamponade in a Cancer Patient

Paradoxical hemodynamic instability is defined as unexpected hemodynamic compromise that develops in a patient after pericardial fluid drainage. The overall incidence of the condition is about 5%, and it has a high in-hospital mortality rate. The condition has been reported to occur regardless of the approach that is used to drain the fluid or the underlying cause of the disease. The pathophysiology of paradoxical hemodynamic instability and the appropriate intervention are not very clear, and further studies are needed to identify appropriate preventive measures.We report a rare manifestation of paradoxical hemodynamic instability in a 65-year-old woman who had a history of stage IV lung cancer. She presented with a one-week history of pleuritic chest pain and shortness of breath on exertion. Echocardiography revealed a large circumferential pericardial effusion with right atrial and ventricular collapse during diastole, suggesting a compressive effect of the pericardial fluid; however, left ventricular systolic function was well preserved. The patient underwent the scheduled creation of a subxiphoid pericardial window. Immediately after the pericardial fluid was evacuated, her heart began to beat more vigorously, but this was abruptly followed by an episode of asystole. Pacing and medical therapy were unsuccessful in preventing repeated episodes of asystole, and the patient died.To our knowledge, this is the 2nd report of unexpected asystole after the creation of a subxiphoid pericardial window, and it is the first report of a takotsubo-like contractile pattern associated with paradoxical hemodynamic instability.Key words: Hemodynamics, neoplasms/physiopathology, pericardial effusion/diagnosis/etiology/surgery/therapy, pericardial window techniques, risk factors, takotsubo cardiomyopathy/complications/physiopathology, ventricular dysfunction, left/complicationsMalignant involvement of the pericardium has been detected on autopsy in up to 20% of cancer patients,¹ and the most common metastatic tumor involving the pericardium is lung cancer.² A pericardial effusion that arises in a patient with a known malignancy usually indicates metastasis.¹ Cardiac tamponade, the most severe consequence of a pericardial effusion, occurs when accumulated fluid compresses the cardiac chambers. The result is reduced venous return and subsequently decreased cardiac output. Most patients who undergo evacuation of a clinically significant pericardial effusion experience rapid improvement in their symptoms and hemodynamic status. We describe the occurrence of an uncommon and frequently fatal³ postoperative sequela of pericardial drainage: paradoxical hemodynamic instability (PHI). Paradoxical hemodynamic instability is defined as unexpected hemodynamic compromise that develops in a patient after pericardial fluid drainage.     

Body size and multiple myeloma mortality: a pooled analysis of 20 prospective studies

Multiple myeloma (MM) is a rare but highly fatal malignancy. High body weight is associated with this cancer, but several questions remain regarding the aetiological relevance of timing and location of body weight. To address these questions, we conducted a pooled analysis of MM mortality using 1·5 million participants (including 1388 MM deaths) from 20 prospective cohorts in the National Cancer Institute Cohort Consortium. Proportional hazards regression was used to calculate pooled multivariate hazard ratios (HRs) and 95% confidence intervals (CIs). Associations with elevated MM mortality were observed for higher early‐adult body mass index (BMI; HR = 1·22, 95% CI: 1·09–1·35 per 5 kg/m²) and for higher cohort‐entry BMI (HR 1·09, 95% CI: 1·03–1·16 per 5 kg/m²) and waist circumference (HR = 1·06, 95% CI: 1·02–1·10 per 5 cm). Women who were the heaviest, both in early adulthood (BMI 25+) and at cohort entry (BMI 30+) were at greater risk compared to those with BMI 18·5 ≤ 25 at both time points (HR = 1·95, 95% CI: 1·33–2·86). Waist‐to‐hip ratio and height were not associated with MM mortality. These observations suggest that overall, and possibly also central, obesity influence myeloma mortality, and women have the highest risk of death from this cancer if they remain heavy throughout adulthood.