High output chyle leak after neck surgery: the role of video-assisted thoracoscopic surgery

Injury to the thoracic duct leading to formation of a chylous fistula is an infrequent but serious complication of major neck surgery that can result in a prolonged stay in hospital, and may lead to fluid, electrolyte, protein, and immune disturbances. Healing can also be impaired. We describe a case where an excessive chylous leak also contributed to the failure of two free flaps in the same patient, and we make recommendations regarding management of patients with free tissue transfer where this complication arises.     

Effects on rats of Commiphora myrrha extract given by different routes of administration.

The effect of an ethanol extract of Commiphora myrrha oleo-gum resin on hematological and pathophysiological parameters of male Wistar rats was examined. The extract was given daily for 2 w at 1000 mg/kg bw per os, 500 mg/kg bw i.m. or 250 mg/kg bw i.p. Depression, huddling together, soft feces, jaundice, ruffled hair, hepatonephropathy, hemorrhagic myositis and patchy peritonitis (at the injection site) and death were accompanied by increases in serum ALP and ALT activities, bilirubin, cholesterol and creatinine concentrations, and decreases in total protein and albumin levels, and macrocytic anemia and leucopenia. When administered at 500 mg extract/kg bw/d per os or 250 mg extract/kg bw/d i.m. for 2 w it was not lethal, and when given daily for 1 w the effect was less marked.     

Glycyrrhizic acid improved lipoprotein lipase expression,insulin sensitivity,serum lipid and lipid deposition in high-fat diet-induced obese rats

Background  

The metabolic syndrome, known also as the insulin resistance syndrome, refers to the clustering of several risk factors for atherosclerotic cardiovascular disease. Dyslipidaemia is a hallmark of the syndrome and is associated with a whole body reduction in the activity of lipoprotein lipase (LPL), an enzyme under the regulation of the class of nuclear receptors known as peroxisome proliferator-activated receptor (PPAR). Glycyrrhizic acid (GA), a triterpenoid saponin, is the primary bioactive constituent of the roots of the shrub Glycyrrhiza glabra. Studies have indicated that triterpenoids could act as PPAR agonists and GA is therefore postulated to restore LPL expression in the insulin resistant state.     

Adenocarcinoma in ileal duplication cyst: Case report and review of literature

Adenocarcinomas of Ileal Duplication Cysts are an extremely rare occurrence, this is a case report and review of current literature as to the best management of this condition.     

Contrast sensitivity based orientation changes in refractive surgery patients

It is well known that refractive surgery leads to an increase in higher-order aberrations. These can cause problems such as glare, starburst and halos in vision, particularly in low light levels when the pupil is large. The overall wavefront aberration of the eye is typically non-circularly symmetric due to the presence of aberrations such as coma and trefoil. These asymmetries have been shown to induce orientation-selective effects in grating-based contrast sensitivity tests. Classically, contrast sensitivity is assumed to be independent of orientation and is measured at only one orientation. Examining more orientations may give a better indicator of visual performance when abnormal amounts of aberration are present. To examine this, contrast sensitivity through a dilated pupil was determined for four orientations of a 12 cycles deg⁻¹ sine wave grating in 12 subjects both before and after refractive surgery. Surgery produced orientation-selective changes in contrast sensitivity in most patients (9 out of 12, p  < 0.05). The correlation between contrast sensitivity and higher-order aberrations was found to improve when several orientations were tested compared with data from only one orientation (combined orientations, r ²  =  0.46 , p =  0.007; single orientation r ² = 0.55, p <  0 .05 to r ² = 0.09, p >  0.05). These results indicate that grating orientation is an important factor when investigating the link between visual performance and higher order aberrations.     

Paired helical filaments associated with Alzheimer disease are readily soluble structures

Considerable controversy exists concerning the origin and composition of Alzheimer neurofibrillary tangles (ANT) and of paired helical filaments (PHF), the abnormal cytoplasmic fibers which ultrastructurally are the major components of ANT. Thus far, the unusual solubility properties of PHF have hindered the analysis of ANT. A new procedure is presented for isolating purified PHF which are soluble in the presence of sodium dodecyl sulfate. The purification protocol involves differential and rate zonal centrifugation, treatment with the detergents sarcosyl and sulfobetain 3-14, and sonication. The isolated PHF from Alzheimer disease/senile dementia of the Alzheimer type (7 cases) and Down's syndrome (one case) have been characterized structurally by negative-stain electron microscopy, biochemically by PAGE, and immunologically by both the ELISA technique and Western blot analysis using a monoclonal antibody prepared against ANT. Distinct polypeptides were shown to be associated with this structure and not seen in preparations from young and age-matched normal brains.     

Adverse effects of observational studies when examining adverse outcomes of drugs: case-control studies with low prevalence of exposure.

OBJECTIVES: The case-control study is commonly used to examine adverse drug events, in which prevalence of exposure in the source population is frequently very low. The objective of the current study was to examine the bias inherent in the odds ratio assessing the association between exposure and an adverse outcome when prevalence of exposure in the source population is extremely low. DESIGN: Monte Carlo simulations examined the effect of sample size, exposure prevalence, and magnitude of the underlying odds ratio on the bias of the estimated risk ratio, and the power to detect a non-zero risk ratio. RESULTS: Once the underlying odds ratio was at least four, the adverse effects of low prevalence of exposure was minimal. Studies with small sample sizes and low prevalence of exposure, coupled with small to moderate effect sizes, can result in biased estimates of association between exposure and disease status. With a sample size of 200 and an exposure prevalence of 0.5% in the control population, the bias in the estimated odds ratio can be as large as 115%. However, bias becomes negligible as sample size becomes large (n > or = 2000), even when prevalence of exposure is very low. Once the expected number of exposed controls is at least eight, the bias in the estimated odds ratio was no more than 5%. CONCLUSIONS: Studies with small sample sizes and low prevalence of exposure, coupled with small to moderate effect sizes can result in biased estimates of association between exposure status and adverse drug effects. However, bias becomes negligible as sample size becomes large.