Oral administration of ascorbic acid attenuates endothelial dysfunction after short-term cigarette smoking

Short-term cigarette smoking is associated with persistent endothelial dysfunction. Data on the reversibility of this effect with per os antioxidants after short-term smoking are lacking. This study examines the effect of orally administered ascorbic acid on cigarette smoking-induced endothelial dysfunction. In the present double-blind, randomized, crossover study, 19 healthy subjects (28.7 +/- 6.8 years, mean +/- SD) were examined by high-resolution ultrasonography of the brachial artery before and 0, 30, 60, 90, and 120 minutes after smoking a cigarette. Flow-mediated dilatation (FMD) was used as a method to examine endothelial function. Measurements were performed on two different days, 2 hours after oral administration of 2 g of ascorbic acid or placebo. FMD was similar for each subject between the two visits at baseline. FMD was significantly decreased after smoking with both placebo and ascorbic acid. However, there was a significant beneficial effect of ascorbic acid on the FMD change over time after smoking. After smoking, the FMD dropped to less than half of the baseline value. Thereafter in the placebo group, FMD increased to 70% of baseline value in 90 minutes, but in the ascorbic acid group the FMD increased to 70% of baseline value in 46 minutes. Oral administration of ascorbic acid attenuates endothelial dysfunction after short-term cigarette smoking by shortening its duration.     

Effect of Portacaval Anastomosis on Glutamine Synthetase Protein and Gene Expression in Brain, Liver and Skeletal Muscle

The effects of chronic liver insufficiency resulting from end-to-side portacaval anastomosis (PCA) on glutamine synthetase (GS) activities, protein and gene expression were studied in brain, liver and skeletal muscle of male adult rats. Four weeks following PCA, activities of GS in cerebral cortex and cerebellum were reduced by 32% and 37% (p<0.05) respectively whereas GS activities in muscle were increased by 52% (p<0.05). GS activities in liver were decreased by up to 90% (p<0.01), a finding which undoubtedly reflects the loss of GS-rich perivenous hepatocytes following portal-systemic shunting. Immunoblotting techniques revealed no change in GS protein content of brain regions or muscle but a significant loss in liver of PCA rats. GS mRNA determined by semi-quantitative RT-PCR was also significantly decreased in the livers of PCA rats compared to sham-operated controls. These findings demonstrate that PCA results in a loss of GS gene expression in the liver and that brain does not show a compensatory induction of enzyme activity, rendering it particularly sensitive to increases in ammonia in chronic liver failure. The finding of a post-translational increase of GS in muscle following portacaval shunting suggests that, in chronic liver failure, muscle becomes the major organ responsible for the removal of excess blood-borne ammonia.     

Src blockade stabilizes a Flk/cadherin complex, reducing edema and tissue injury following myocardial infarction

Ischemia resulting from myocardial infarction (MI) promotes VEGF expression, leading to vascular permeability (VP) and edema, a process that we show here contributes to tissue injury throughout the ventricle. This permeability/edema can be assessed noninvasively by MRI and can be observed at the ultrastructural level as gaps between adjacent endothelial cells. Many of these gaps contain activated platelets adhering to exposed basement membrane, reducing vessel patency. Following MI, genetic or pharmacological blockade of Src preserves endothelial cell barrier function, suppressing VP and infarct volume, providing long-term improvement in cardiac function, fibrosis, and survival. To our surprise, an intravascular injection of VEGF into healthy animals, but not those deficient in Src, induced similar endothelial gaps, VP, platelet plugs, and some myocyte damage. Mechanistically, we show that quiescent blood vessels contain a complex involving Flk, VE-cadherin, and beta-catenin that is transiently disrupted by VEGF injection. Blockade of Src prevents disassociation of this complex with the same kinetics with which it prevents VEGF-mediated VP/edema. These findings define a molecular mechanism to account for the Src requirement in VEGF-mediated permeability and provide a basis for Src inhibition as a therapeutic option for patients with acute MI.     

Sex differences in memory processing in schizophrenia: an event-related potential (ERP) study

Recently, research has begun to examine sex differences in cognitive functions in schizophrenia and whether such sex differences reflect normal, exaggerated, or reversed sexual dimorphism. This study examined this question by using event-related potentials (ERPs). ERPs were recorded in a recognition memory task in 18 patients and 18 matched control subjects. On an early frontal component, the results show an interaction between sex and pathological condition that results in an apparent reversed sexual dimorphism. On mid-latency components, patients show no sex difference on a frontal component, but a difference on the posterior component, whereas healthy subjects show a reverse pattern. Finally, late components show sex difference in the same direction as healthy subjects. These results indicate that the influence of sex on the cognitive impairment in schizophrenia is not homogenous across the information-processing cascade.     

Heat therapy in the management of heart failure

Heart failure remains a health care epidemic, and additional complementary therapies beyond pharmaceuticals and devices are needed. Using heat therapy or topical thermal therapy is an ancient therapeutic approach for the treatment of heart failure. Currently, there are several studies reporting salutary effects of heat therapy in patients with heart failure using either dry heat or water immersion therapies. The authors describe an additional theoretic construct using topically applied heat pads that might be a simple and economic approach to affect heat therapy as an adjunct for many patients. Hopefully future studies will continue to explore heat therapy as adjunctive care for heart failure patients.     

Children with seizures exhibit preferences for foods compatible with the ketogenic diet

Although highly effective for the treatment of intractable epilepsy, the ketogenic diet is not always included in the treatment option hierarchy presented to families, in part due to perceptions that children will find the high-fat/low-carbohydrate regimen unpalatable. This study assessed if children with seizures exhibit food preferences compatible with the diet, as well as if caregivers were accurate in predicting preferences. Children aged 2-17, with (n=29) and without (n=30) a history of seizures, participated in a paired choice food preference assessment while parents estimated child preferences verbally. Children with seizures exhibited significantly higher preferences for fat versus carbohydrate foods compared with controls, and parents demonstrated low accuracy. Future studies could use similar assessment methods to prospectively track whether such preferences predict diet compliance and/or efficacy. Research into the underlying metabolic basis for this preference and possible related neurophysiological mechanisms in seizure etiology and treatment is warranted.     

Effects of cigarette smoking and abstinence on stroop task performance

Rationale Smokers report enhanced concentration after cigarette smoking and difficulty concentrating when abstinent from smoking. These perceived effects may contribute to smoking cessation failures, and if so, clarification of their cognitive bases could inform treatment strategies. Selective attention may be important in this regard, but earlier literature presents inconsistent findings on how smoking abstinence and resumption of smoking influence this cognitive function. Objectives We aimed to compare smokers and nonsmokers on selective attention, and in smokers, to test the effects of overnight abstinence from smoking and of acute smoking on selective attention. Materials and methods Smokers and nonsmokers (n = 43) performed a Stroop test (two test days, two test blocks per day). Smokers participated after overnight abstinence and also within 1-h of ad libitum smoking. Smokers each smoked a cigarette between test blocks on each day; nonsmokers did not. Results Smokers demonstrated longer response latencies for both congruent and incongruent stimuli after overnight than brief abstinence, but no deficit specifically related to selective attention. Whereas nonsmokers showed no changes in performance in the second test block, smoking between blocks reduced the Stroop effect when smokers were abstinent overnight. Conclusions These data are consistent with the hypothesis that abstinence from smoking among nicotine-dependent individuals has deleterious effects on cognitive performance, but do not indicate that selective attention is adversely effected. Improvement in selective attention after terminating abstinence with one cigarette may also contribute to smokers’ perceived enhanced ability to concentrate after smoking.     

Eosinophilic fascitis: a report of two cases treated with ultraviolet A1 phototherapy

Eosinophilic fascitis (EF) (synonyms: Shulman's syndrome, diffuse fascitis with eosinophilia) is a disease characterized by a complex set of symptoms with scleroderma-like skin lesions, the absence of Raynaud's phenomenon and other non-mandatory symptoms including eosinophilia, elevated erythrocyte sedimentation rate, hypergammaglobulinemia and high levels of circulating immune complexes. EF is probably not a separate disease entity, but an acute variant of localized scleroderma. This rare disease of unknown etiology is usually seen in middle-aged adults. Sclerodermiform indurations without Raynaud's symptoms develop rapidly usually on the extremities and more rarely on the trunk or the face. The skin becomes hard, tightly bound to the underlying structures, so that contractures can develop in as little as a few weeks. The course of the disease is usually chronic but spontaneous remission is possible. Standard therapy includes high doses of corticosteroids, immunosuppressive drugs such as methotrexate, cyclosporin A, cyclophosphamide or azathioprine and others such as psoralen and ultraviolet A radiation.     

Posttraumatic stress and related symptoms among neglected and physically and sexually maltreated adolescents

Posttraumatic stress disorder (PTSD) is common among maltreated youth, but few investigations compare neglect with other maltreatment types. This study examined 84 adolescents who experienced neglect only, physical and/or sexual maltreatment only, or neglect with physical and/or sexual maltreatment. Symptoms of PTSD, dissociation, and depression were measured. Adolescents who experienced physical and/or sexual maltreatment, whether neglected or not, reported significantly greater symptomatology than adolescents who experienced neglect only (η2 = .094). This difference applied to PTSD symptoms, dissociative amnesia, depersonalization and derealization, negative mood, and anhedonia. Adolescents exposed to neglect only displayed substantial psychopathology but less than that of other groups. The findings may reflect emerging cascade models of the etiology of symptoms of PTSD following extensive maltreatment history.