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1.
Summary Mechanisms for maintaining passive continence in the efferent limb of urinary diversions include compression of tissue, peristalsis, equilibration of pressure and use of valves. Motor activity and pressure in the ileum, ileocecal valve (ICV) and the colon were evaluated in dogs. Spontaneous activity and pressure were compared with stimulated pressure response and activity. Stimulation was performed at the pelvic nerve and the small nerves in the mesenterium, as well as direct neurostimulation of the bowel. Resting pressure at the ICV was 12.7±0.4 cmH2O rising to 26.4±2.2 cmH2O during spontaneous depolarization. Stimulation of the pelvic nerve resulted in increased colonic motor activity with unchanged pressure. Electric stimulation of small mesenterical nerves to the ICV increased pressure in the ICV to 35.0±4.1 cmH2O, while direct myoelectric stimulation of the ICV zone increased the intraluminal pressure to 75.0±3.2 cmH2O. Termination of the electric stimulation was followed by a slow decrease of pressure to the resting level a period of 30–45 s. Maintaining continence at the ICV with long-term constant or intermittent stimulation seems feasible.  相似文献   
2.
A new immunochromatographic rapid test (Rapid Check HIV 1 and 2; Núcleo de Doen?as Infecciosas) for the detection of antibodies to human immunodeficiency virus type 1 and type 2 in human samples (whole blood, serum, and plasma) was evaluated and compared to the commercially available Determine (Abbott Laboratories). When whole-blood samples were evaluated, the specificity and sensitivity of both tests were 100%. However, when plasma samples were used, sensitivity for the Rapid Check HIV 1&2 and the Determine tests were 100 and 98.58%, respectively. The observed specificity for plasma samples was 98.94% for the Rapid Check HIV 1&2 and 96.97% for the Determine test. The results presented here are encouraging and support the adoption of both tests as an alternative to enzyme-lined immunosorbent assay and/or Western blots in regions where laboratorial infrastructure is not available or for use in the management of occupational accidents for healthcare workers.  相似文献   
3.
Human ORFeome Version 1.1: A Platform for Reverse Proteomics   总被引:6,自引:0,他引:6       下载免费PDF全文
The advent of systems biology necessitates the cloning of nearly entire sets of protein-encoding open reading frames (ORFs), or ORFeomes, to allow functional studies of the corresponding proteomes. Here, we describe the generation of a first version of the human ORFeome using a newly improved Gateway recombinational cloning approach. Using the Mammalian Gene Collection (MGC) resource as a starting point, we report the successful cloning of 8076 human ORFs, representing at least 7263 human genes, as mini-pools of PCR-amplified products. These were assembled into the human ORFeome version 1.1 (hORFeome v1.1) collection. After assessing the overall quality of this version, we describe the use of hORFeome v1.1 for heterologous protein expression in two different expression systems at proteome scale. The hORFeome v1.1 represents a central resource for the cloning of large sets of human ORFs in various settings for functional proteomics of many types, and will serve as the foundation for subsequent improved versions of the human ORFeome.  相似文献   
4.
Sputum and serum from patients with active pulmonary tuberculosis (TB), healthy purified protein derivative-positive adults, and patients with bacterial pneumonia were collected to simultaneously assess local immunity in the lungs and peripheral blood. To determine whether cytokine profiles in sputum from TB patients and control subjects were a reflection of its cellular composition, cytospin slides were prepared in parallel and assessed for the presence of relative proportions of epithelial cells, neutrophils, macrophages, and T cells. Gamma interferon (IFN-γ) in sputum from TB patients was markedly elevated over levels for both control groups. With anti-TB therapy, IFN-γ levels in sputum from TB patients decreased rapidly and by week 4 of treatment were comparable to those in sputum from controls. Further, IFN-γ levels in sputum closely followed mycobacterial clearance. Although detected at fourfold-lower levels, IFN-γ immunoreactivities in serum followed kinetics in sputum. TNF-α, interleukin 8 (IL-8) and IL-6 also were readily detected in sputum from TB patients at baseline and responded to anti-TB therapy. In contrast to IFN-γ, however, TNF-α and IL-8 levels also were elevated in sputum from pneumonia controls. These data indicate that sputum cytokines correlate with disease activity during active TB of the lung and may serve as potential early markers for sputum conversion and response to anti-TB therapy.  相似文献   
5.
Mexican-American children are shorter but relatively heavier than non-Hispanic white children. The excess relative weight is probably due to increased fat rather than lean body mass and, more specifically, to increased fat deposition on the upper trunk sites. The objective of this paper is to describe the level of fatness and fat distribution in a large, representative sample of Mexican- American children and adolescents from the recently completed Hispanic Health and Nutrition Examination Survey (HHANES). As expected, Mexican-American children are generally fatter than white children measured in previous national surveys (National Health and Nutrition Examination Survey [NHANES] II, Health Examination Survey [HES]). Differences are particularly evident for trunk skinfold thicknesses and generally increase with age. Indices of fat distribution clearly show a centralized, upper body adiposity pattern among Mexican-Americans, a cause for concern since greater fat deposition on the trunk has been associated with increased risk of certain chronic disease.  相似文献   
6.
The first version of the Caenorhabditis elegans ORFeome cloning project, based on release WS9 of Wormbase (August 1999), provided experimental verifications for ~55% of predicted protein-encoding open reading frames (ORFs). The remaining 45% of predicted ORFs could not be cloned, possibly as a result of mispredicted gene boundaries. Since the release of WS9, gene predictions have improved continuously. To test the accuracy of evolving predictions, we attempted to PCR-amplify from a highly representative worm cDNA library and Gateway-clone ~4200 ORFs missed earlier and for which new predictions are available in WS100 (May 2003). In this set we successfully cloned 63% of ORFs with supporting experimental data (“touched” ORFs), and 42% of ORFs with no supporting experimental evidence (“untouched” ORFs). Approximately 2000 full-length ORFs were cloned in-frame, 13% of which were corrected in their exon/intron structure relative to WS100 predictions. In total, ~12,500 C. elegans ORFs are now available as Gateway Entry clones for various reverse proteomics (ORFeome v3.1). This work illustrates why the cloning of a complete C. elegans ORFeome, and likely the ORFeomes of other multicellular organisms, needs to be an iterative process that requires multiple rounds of experimental validation together with gradually improving gene predictions.  相似文献   
7.
To elucidate the host cell machinery utilized by Chlamydia trachomatis to invade epithelial cells, we examined the role of the actin cytoskeleton in the internalization of chlamydial elementary bodies (EBs). Treatment of HeLa cells with cytochalasin D markedly inhibited the internalization of C. trachomatis serovar L2 and D EBs. Association of EBs with HeLa cells induced localized actin polymerization at the site of attachment, as visualized by either phalloidin staining of fixed cells or the active recruitment of GFP-actin in viable infected cells. The recruitment of actin to the specific site of attachment was accompanied by dramatic changes in the morphology of cell surface microvilli. Ultrastructural studies revealed a transient microvillar hypertrophy that was dependent upon C. trachomatis attachment, mediated by structural components on the EBs, and cytochalasin D sensitive. In addition, a mutant CHO cell line that does not support entry of C. trachomatis serovar L2 did not display such microvillar hypertrophy following exposure to L2 EBs, which is in contrast to infection with serovar D, to which it is susceptible. We propose that C. trachomatis entry is facilitated by an active actin remodeling process that is induced by the attachment of this pathogen, resulting in distinct microvillar reorganization throughout the cell surface and the formation of a pedestal-like structure at the immediate site of attachment and entry.  相似文献   
8.
Multiple disorders once jointly conceived as “nervous diseases” became segregated by the distinct institutional traditions forged in neurology and psychiatry. As a result, each field specialized in the study and treatment of a subset of such conditions. Here we propose new avenues for interdisciplinary interaction through a triangulation of both fields with social neuroscience. To this end, we review evidence from five relevant domains (facial emotion recognition, empathy, theory of mind, moral cognition, and social context assessment), highlighting their common disturbances across neurological and psychiatric conditions and discussing their multiple pathophysiological mechanisms. Our proposal is anchored in multidimensional evidence, including behavioral, neurocognitive, and genetic findings. From a clinical perspective, this work paves the way for dimensional and transdiagnostic approaches, new pharmacological treatments, and educational innovations rooted in a combined neuropsychiatric training. Research-wise, it fosters new models of the social brain and a novel platform to explore the interplay of cognitive and social functions. Finally, we identify new challenges for this synergistic framework.  相似文献   
9.
INTRODUCTION AND OBJECTIVES: To evaluate the clinical characteristics and prognosis of heart failure (HF) development in patients hospitalized for acute myocardial infarction (AMI). PATIENTS AND METHOD: Between May 1990 and March 2000, 836 consecutive patients were admitted with a diagnosis of AMI within 24 h of symptom onset. HF was defined as the presence of rales and a third heart sound with gallop, and evidence of pulmonary congestion on chest x-ray. It was diagnosed in 263 subjects (31.5%). RESULTS: The mean age of patients with HF (group 1) was 63.4 (11.4) years compared with 59.9 (11.6) years in those without HF (group 2) (P<.01). There were differences between groups 1 and 2 in history of diabetes (36% vs 20%; P<.001) or previous HF (9.2% vs 1.1%; P<.001). The reperfusion strategy used in patients with Q-wave infarction, with or without HF, was primary angioplasty in 15% and 14%, respectively (P=.81), and thrombolytic agents in 28% and 37%, respectively (P=.013). Patients with HF were more likely to develop recurrent angina (26.8% vs 19.6%; P=.02), pericarditis (17.5% vs 6.3%; P<.001), and atrial fibrillation (12.3% vs 5.1%; P<.01). In-hospital mortality in groups 1 and 2 was 15.6% and 2.3% (P<.001), respectively, and 10-year survival was 10% and 30%, respectively (P<.001). The variables associated with mortality were: age (HR=1.022; P<.001), hyperglycemia (HR=1.748 per 1.0-g/L increase; P<.001), leukocytosis (HR=1.035 per 1000-cell/.L increase; P<.001), and HF (HR=1.308; P=.028). CONCLUSIONS: AMI is still frequently complicated by HF, which increases short- and long-term morbidity and mortality. Heart failure, age, hyperglycemia, and leukocytosis at admission were independent predictors of mortality during follow-up.  相似文献   
10.
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