Lack of effect of sugar cane policosanol on plasma cholesterol in Golden Syrian hamsters

Policosanol is a mixture of higher aliphatic alcohols shown to have beneficial effects on plasma lipid levels in animals and humans. Over 50 studies have reported significant reductions in plasma cholesterol using policosanol obtained from Cuban sugar cane (Dalmer, La Havana, Cuba). However, other research groups using policosanol from alternative sources have failed to reproduce the efficacy of these alcohols observed in earlier studies. Therefore, the objective of the present study was to compare the cholesterol-lowering effect of the Dalmer sugar cane policosanol (SCP) product versus an alternative mixture of similar policosanol composition. Forty-eight male Golden Syrian hamsters were randomly assigned to four groups and fed experimental diets ad libitum for a period of 4 weeks: (i) non-cholesterol control, (ii) 0.1% cholesterol control, (iii) 0.1% cholesterol diet supplemented with 275 mg/kg diet of Dalmer Cuban sugar cane policosanol and (iv) 0.1% cholesterol diet supplemented with 275 mg/kg diet of alternative sugar cane policosanol. Hamsters were sacrificed and blood was collected at the end of the feeding period. Body weights and food intakes were similar across study groups. Neither of the two policosanol treatments had any significant effect on plasma lipid levels, as compared to cholesterol control. The outcome of the present study questions the clinical usefulness of policosanol mixtures as cholesterol-lowering nutraceuticals.     

Metabolic syndrome: an evolving threat in the genesis of coronary artery disease

Cardiovascular disease is an escalating worldwide health problem. Effective tools to predict and prevent its development and progression are needed. Correctly diagnosing the metabolic syndrome, which identifies people at higher risk for developing diabetes mellitus and cardiovascular disease, may be valuable in guiding treatment and prevention of these major disorders. Several important definitions of the metabolic syndrome have been proposed. The authors discuss these definitions and how they vary in terms of their relationship to incident cardiovascular disease, type 2 diabetes mellitus, and surrogate markers of atherosclerosis. Establishing clarity on what is meant by the metabolic syndrome and agreement as to its underlying basis is needed to reach consensus between the many different definitions that have been proposed. This is particularly the case if it is to become a useful adjunct in clinical practice to identify those who may benefit from more intensive lifestyle interventions and more detailed short-term risk assessments.     

Congenital cystic eye: features on MRI

Congenital cystic eye is a rare cause of cystic orbital lesion. The condition is recognized at birth as a large orbital mass in place of a normal eye. Only 29 cases have been reported previously. We report a case of unilateral congenital cystic eye with multiple brain anomalies in the form of agenesis of corpus callosum and grey matter heterotopias. In this case report we highlight the MRI features of this entity, which have not been described previously in the literature.     

Role of perfusion CT in glioma grading and comparison with conventional MR imaging features

BACKGROUND AND PURPOSE: Perfusion imaging using CT can provide additional information about tumor vascularity and angiogenesis for characterizing gliomas. The purpose of our study was to demonstrate the usefulness of various perfusion CT (PCT) parameters in assessing the grade of treatment-naïve gliomas and also to compare it with conventional MR imaging features.MATERIALS AND METHODS: PCT was performed in 19 patients with glioma (14 high-grade gliomas and 5 low-grade gliomas). Normalized ratios of the PCT parameters (normalized cerebral blood volume [nCBV], normalized cerebral blood flow [nCBF], normalized mean transit time [nMTT]) were used for final analysis. Conventional MR imaging features of these tumors were assessed separately and compared with PCT parameters. Low- and high-grade gliomas were compared by using the nonparametric Wilcoxon 2-sample tests.RESULTS: Mean nCBV in the high- and low-grade gliomas was 3.06 ± 1.35 and 1.44 ± 0.42, respectively, with a statistically significant difference between the 2 groups (P = .005). Mean nCBF for the high- and low-grade gliomas was 3.03 ± 2.16 and 1.16 ± 0.36, respectively, with a statistically significant difference between the 2 groups (P = .045). Cut points of >1.92 for nCBV (85.7% sensitivity and 100% specificity), >1.48 for nCBF (71.4% sensitivity and 100% specificity), and <1.94 for nMTT (92.9% sensitivity and 40% specificity) were found to identify the high-grade gliomas. nCBV was the single best parameter; however, using either nCBV of >1.92 or nCBF of >1.48 improved the sensitivity and specificity to 92.9% and 100%, respectively. The sensitivity and specificity for diagnosing a high-grade glioma with conventional MR imaging were 85.7% and 60%, respectively.CONCLUSIONS: PCT can be used for preoperative grading of gliomas and can provide valuable complementary information about tumor hemodynamics, not available with conventional imaging techniques. nCBV was the single best parameter correlating with glioma grades, though using nCBF when nCBV was <1.92 improved the sensitivity. An nCBV threshold of >1.92 was found to identify the high-grade gliomas.

Gliomas, the most common primary brain neoplasms in adults, are very heterogeneous tumors. High-grade gliomas can be highly invasive and extremely vascular tumors.Glioma grading is currently based on the histopathologic assessment of the tumor, which is achieved by stereotactic brain biopsy or cytoreductive surgery; and there are inherent limitations with these techniques and their interpretation.¹ Therapeutic approaches, response to therapy, and prognosis depend on accurate grading, and thus finding the part of the tumor with the highest grade to be biopsied is critical.Conventional MR imaging has a limited role in differentiating gliomas because contrast-enhanced images reveal disrupted or absent blood-brain barrier and not necessarily microvascularity or neovascularity of the tumoral lesion.^2,3 The 2 most important factors in determining the malignancy of gliomas is their ability to infiltrate the brain parenchyma and to recruit or synthesize vascular networks for further growth.⁴Malignant brain tumors are characterized by neovascularity and increased angiogenic activity, with a higher proportion of immature and hyperpermeable vessels.^5,6 Because vascular proliferation is an important characteristic in the grading of astrocytomas,⁷ imaging techniques that provide hemodynamic information about the tumor may help in characterizing glioma malignancy, which may overcome some of the limitations of histopathologic sampling error and conventional MR imaging. Perfusion imaging has been useful in grading cerebral neoplasms^8–14 and may provide reliable information on tumor physiology such as microvascularity, angiogenesis, micronecrosis, and cellularity.Perfusion imaging of brain tumors has shown that certain cerebral perfusion parameters such as regional blood volume and blood flow correlate well with tumor grade, and it has also been helpful in distinguishing recurrent tumor from radiation necrosis.^3,15Most of the prior perfusion studies comparing histologic features with perfusion parameters have used various MR perfusion techniques.^3,15 However, recently perfusion CT (PCT) has been used as an alternative method in assessing cerebral hemodynamics for stroke and brain tumors.¹⁶ PCT allows measurement of tumor vascular physiology, and maps of tumor blood flow, blood volume, mean transit time (MTT), and permeability–surface area product can be generated. In view of the wider availability, faster scanning times, and low cost combined with its ease of quantification of various perfusion parameters as compared with MR perfusion, PCT is potentially well suited to studying brain tumors and monitoring tumor response to antiangiogenic agents.¹⁶The purpose of our study was to demonstrate the usefulness of various PCT parameters such as cerebral blood volume (CBV), cerebral blood flow (CBF), and MTT in assessing the grade of treatment-naïve gliomas and also to compare them with conventional MR features.     

Comorbidities play a larger role in predicting health-related quality of life compared to having an ostomy

BACKGROUND: Previous research suggests an ostomy worsens health-related quality of life (HR-QOL), but comorbidities also can affect HR-QOL. METHODS: Eligible patients had abdominal operation with ostomy (cases) or similar procedure without ostomy (controls). Patients were recruited for this case-control study from 3 Veterans Affairs hospital medical and pharmacy records. Comorbidities were assessed with Charlson-Deyo Comorbidity Index. Multinomial logistic regression evaluated the impact of comorbidities and having an ostomy on HR-QOL, measured using the Medical Outcomes Study Short Form 36 for Veterans. RESULTS: A total of 237 ostomates (cases) and 268 controls were studied. Average age was 69 years; 64% of cases had colostomy, 36% ileostomy. Twenty-nine percent of patients had a high level of comorbidities. Cases and controls were similar except for reasons for undergoing surgery. High comorbidity was a significant predictor of low HR-QOL in 6 domains of the Short Form 36 for Veterans; having an ostomy was a significant predictor in 4. CONCLUSIONS: High comorbidity significantly influences low HR-QOL and impacted more domains than having an ostomy.     

Localized pericardial constriction resulting in a "dumbbell" heart

We describe an unusual case of a young man presenting with calcific constrictive pericarditis. The patient had a history of restrictive cardiomyopathy and pericardial effusion during infancy and received antituberculous treatment. Investigations revealed the presence of thickened pericardium and a thickened calcific constrictive band around the atrioventricular groove posteriorly and over the infundibulum anteriorly. Intraoperatively, the band caused the heart to have a "dumbbell" appearance. A pericardiectomy was performed along with excision of the constricting band. The patient had an uneventful recovery.