The persistence of fatigue in chronic fatigue syndrome and multiple sclerosis: development of a model

Muscle wasting and weakness are common features of patients with critical illnesses, and may impair their recovery. This study examines whether cytoskeletal and contractile proteins are damaged, and which proteolytic mechanisms might be involved, in the muscle fibre atrophy or necrosis associated with the acute myopathy of critically ill patients. Ninety-eight muscle biopsies were obtained by the conchotome method from 57 critically ill patients and examined morphometrically and by immunohistochemical labelling. Sequential biopsies showed a mean reduction in fibre cross-sectional areas of 3-4% per day. More intense immunolabelling for desmin was seen in the smaller fibres of 52% of the biopsies, while immunolabelling for dystrophin, actin and myosin heavy chains was maintained. Myosin ATPase activity was weak in the smaller fibres in some biopsies, and electron microscopy showed the loss of myosin filaments in atrophic fibres. These changes suggest that loss of the filamentous structure of myosin, without degradation of the immunolabelled epitopes, leads to the collapse of the intermyofibrillar desmin network. Fibres with abnormal desmin labelling showed increased cathepsin B, lysozyme and ubiquitin immunolabelling. Nine cases showed increased immunolabelling for heat shock protein 72. The changes in desmin immunolabelling were more prevalent in patients with higher APACHE II scores on admission, but were not related to other clinical features. The results indicate that fibre atrophy is associated with myosin filament depolymerization and the presence of several proteolytic enzymes. In our study, these changes occurred in patients who were critically ill but who did not receive large doses of steroids or neuromuscular blocking agents.     

Angular dependence of the magnetoresistivity of Pd2Si

We present the magnetoresistivity at high magnetic field measured on single crystals of Pd₂Si of very good quality. The magnetoresistance depends on the orientation of field and current directions relative to the crystallographic axis. It shows that this suicide behaves like a compensated metal (i.e. equal numbers of electrons and holes) with open orbits along the main crystallographic directions.     

Antioxidant activity of 1,3-dicaffeoylquinic acid isolated from Inula viscosa

Inula viscosa is a perennial herbaceous plant used topically in folk medicine as an anti-scabies, anti-inflammatory, and wound-healing agent. We examined the antioxidant activity of the methanolic extract of I. viscosa. We isolated and identified several polyphenolic antioxidants from I. viscosa leaves and focused on 1,3-dicaffeoylquinic acid (1,3-diCQA). Antioxidant activity was measured using ABTS and DPPH assays, which measure antioxidant activity. The concentrations of 1,3-diCQA required for the inhibition of oxidation were lower than those required by other known antioxidants. 1,3-diCQA inhibited oxidative damage caused by various factors, including FeSO₄ and AAPH (2,2′-azobis(2-amidinopropane) dehydrochloride). Antioxidant activity can also be detected by the ability of a compound to scavenge reactive oxygen species (ROS). 1,3-diCQA was found to scavenge hydroxyl radical and superoxide radicals, as measured by electron spin resonance (ESR). These data demonstrate that 1,3-diCQA exhibits antioxidant properties, probably through the involvement of a direct scavenging effect on several free radicals.     

美专家支招收复女孩玩具市场失地

在美国,由于各方面的因素使得女孩越来越早地离开玩具,其市场规模很大程度上变成了由男孩玩具主导。导致这种现象的原因是什么？能否改变这种状况？美国一家商业咨询公司的总裁、有35年消费者产品经验的Richard Gottlieb提出了他的观点。     

Cerebral dominance and speech acquisition in deaf children.

In examining the prediction that left cerebral dominance, as indexed by hand and sighting preference, should be a positive accompaniment of speech learning in individuals whose cerebral speech areas are likely to be in the left hemisphere, it was found that over a 10-12 year period of formal education right-handed-right-sighting deaf students consistently earned higher speech grades than their right-handed-left sighting and right-handed-mixed-sighting counterparts matched on the basis of hearing loss. This finding supports the hypothesis that the cerebral mechanisms relevant to speech acquisition are simplified, facilitated, and/or less prone to interference when control of speech, hand, and eye is localized primarily in 1 hemisphere of the brain. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mathematical Analysis and Optimization of Infiltration Processes

A variety of infiltration techniques can be used to fabricate solid materials, particularly composites. In general these processes can be described with at least one time dependent partial differential equation describing the evolution of the solid phase, coupled to one or more partial differential equations describing mass transport through a porous structure. This paper presents a detailed mathematical analysis of a relatively simple set of equations which is used to describe chemical vapor infiltration. The results demonstrate that the process is controlled by only two parameters, and . The optimization problem associated with minimizing the infiltration time is also considered. Allowing and to vary with time leads to significant reductions in the infiltration time, compared with the conventional case where and are treated as constants.     

Partial-thickness tears of the rotator cuff: evaluation and management

The approach to management of a partial-thickness rotator cuff tear is best made with the understanding that this is not a singular condition. Rather, partial tears represent the common outcome of a variety of insults to the rotator cuff. Degenerative changes due to aging, anatomic impingement, and trauma may all be etiologic agents. Overhead athletes may develop tears due to repetitive microtrauma or internal impingement. Outlet radiographs and magnetic resonance imaging are recommended for routine preoperative evaluation. A nonoperative treatment program for rotator cuff strengthening and stretching is appropriate as initial treatment; modification of activities and anti-inflammatory medication are often used as well. Operative management may be considered when nonoperative treatment fails. Arthroscopic evaluation is required to determine the true extent of the cuff lesion. Arthroscopic subacromial decompression is recommended when outlet impingement is present. Rotator cuff debridement or formal cuff repair is dependent on the size of the cuff defect and the age and activity level of the patient. The importance of recognizing the different causes of partial-thickness rotator cuff tears is emphasized in this review of pathogenesis, clinical diagnosis, imaging, and treatment.     

Double-blind, placebo-controlled study of the effects of carvedilol in patients with moderate to severe heart failure. The PRECISE Trial. Prospective Randomized Evaluation of Carvedilol on Symptoms and Exercise

BACKGROUND: Carvedilol has improved the symptomatic status of patients with moderate to severe heart failure in single-center studies, but its clinical effects have not been evaluated in large, multicenter trials. METHODS AND RESULTS: We enrolled 278 patients with moderate to severe heart failure (6-minute walk distance, 150 to 450 m) and a left ventricular ejection fraction < or = 0.35 at 31 centers. After an open-label, run-in period, each patient was randomly assigned (double-blind) to either placebo (n = 145) or carvedilol (n = 133; target dose, 25 to 50 mg BID) for 6 months, while background therapy with digoxin, diuretics, and an ACE inhibitor remained constant. Compared with placebo, patients in the carvedilol group had a greater frequency of symptomatic improvement and lower risk of clinical deterioration, as evaluated by changes in the NYHA functional class (P = .014) or by a global assessment of progress judged either by the patient (P = .002) or by the physician (P < .001). In addition, treatment with carvedilol was associated with a significant increase in ejection fraction (P < .001) and a significant decrease in the combined risk of morbidity and mortality (P = .029). In contrast, carvedilol therapy had little effect on indirect measures of patient benefit, including changes in exercise tolerance or quality-of-life scores. The effects of the drug were similar in patients with ischemic heart disease or idiopathic dilated cardiomyopathy as the cause of heart failure. CONCLUSIONS: These findings indicate that, in addition to its favorable effects on survival, carvedilol produces important clinical benefits in patients with moderate to severe heart failure treated with digoxin, diuretics, and an ACE inhibitor.     

Thyrotropin receptor antibodies in parotid saliva

Parotid saliva was collected with a Carlson-Crittenden device, under citric acid stimulation, in 18 patients with autoimmune thyroid disease. Thyrotropin Receptor Antibodies (TRAb) were measured with a radioreceptor assay in parotid saliva and in serum in the same patients, and a statistical analysis of the data was performed. TRAb levels in parotid saliva were higher than in serum in the 3 pathologies studied (Graves' disease, Hashitoxicosis and Hashimoto's thyroiditis). There was good correlation between salivary and serum levels.     

Effect of 14 days'' subcutaneous administration of the human amylin analogue, pramlintide (AC137), on an intravenous insulin challenge and response to a standard liquid meal in patients with IDDM

Individuals with insulin-dependent diabetes mellitus (IDDM or type 1 diabetes) are deficient in both insulin and amylin, peptides secreted by the beta cell. We have investigated the effects of amylin replacement therapy employing the human amylin analogue, pramlintide (25, 28, 29-pro-human amylin, previously referred to as AC137), upon the responses to a standardized insulin infusion (40 mU. kg-1. h-1) for 100 min and a liquid Sustacal meal (360 kcal) in 84 healthy IDDM patients. Following baseline evaluations, patients were randomly assigned to receive subcutaneous injections of placebo, 30, 100 or 300 micrograms pramlintide 30 min before meals for 14 days. There was no meaningful difference between adverse events reported by the 30-micrograms pramlintide and the placebo groups, but ten subjects withdrew due to nausea, eight of these in the 300-micrograms dose group. Peak plasma pramlintide concentrations for the 30-micrograms group were 21 +/- 3 and 29 +/- 5 pmol/l on Days 1 and 14, respectively. These values are similar to postprandial plasma amylin concentrations in normal volunteers. The plasma glucose, free insulin, glucagon, epinephrine and norepinephrine concentrations during the insulin infusion test before and after therapy were identical in each of the group. Prior to pramlintide therapy, Sustacal ingestion produced a 4.0-4.8 mmol/l rise in plasma glucose concentrations in each of the groups. Pramlintide therapy reduced postprandial hyperglycaemia as reflected by the 3-h incremental AUCglucose (AUCglucose above or below fasting glucose concentration) Day 1 vs Day 14: 30 micrograms, 322 +/- 92 vs -38 +/- 161 mmol/l.min, p = 0.010; 100 micrograms, 317 +/- 92 vs -39 +/- 76 mmol/l.min, p = 0.001; and 300 micrograms, 268 +/- 96 vs -245 +/- 189 mmol/l.min, p = 0.077. Thus, pramlintide therapy with these regimens did not appear to impair either in vivo insulin action or the counter-regulatory response to hypoglycaemia but did show a clear effect of blunting postprandial hyperglycaemia following a standardized meal.