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991.
In a current publications, it has been suggested that hypoxia-triggered "good angiogenesis" involving hypoxic up-regulation of vascular endothelial growth factor (VEGF) molecules, genes, and receptors is likely responsible in a major way for the remarkable gut and patient salvage experience associated with use of the "patch, drain, and wait" (PD&W) surgical approach to perforated necrotizing enterocolitis and midgut volvulus (MGV) with extensive ischemia/necrosis. We report a case in which extensive ischemia/necrosis in a newborn with gastroschisis (likely MGV-induced) was managed successfully by PD&W with an associated marked (24-fold) elevation of VEGF in drainage fluid at 7 days post-initiation of PD&W.  相似文献   
992.
We tested if ankyrin G could be detected in human neuroma, if it colocalized with site-specific peripheral nerve sodium channels that accumulate at axon tips of injured nerve, and if there are differences in the distribution of these proteins in non-painful neuroma and painful neuroma tissue vs. normal nerve. Frozen sections from one painful, six non-painful, and three normal nerves were immunocytochemically examined. A double labeling technique with highly specific antibodies against peripheral nerve type 1 (Na(v)1.7), and peripheral nerve type 3 (Na(v)1.8) sodium channels and anti-ankyrin G antibodies detected sodium channels and ankyrin G on the same section, using confocal laser scanning microscopy. Ankyrin G colocalized with both types of sodium channels. Neuroma specimens exhibited considerably larger immunofluorescence for both sodium channels and ankyrin G compared with normal nerve. The painful neuroma presented an even more pronounced immunolabeling in clusters. Findings support results from animal models that link ankyrin G with clustering of sodium channels at axon tips of unmyelinated, sprouting fibers. A common (repair-) mechanism that exists throughout the human nervous system for clustering sodium channels at a high density is assumed. A dysregulation in this membrane remodeling mechanism might be an initial step in a cascade that leads to a painful rather than a non-painful neuroma.  相似文献   
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The ex vivo cytokine response to lipopolysaccharide (LPS) of whole blood from patients with typhoid fever was investigated. Tumor necrosis factor (TNF)-alpha release by LPS-stimulated blood was found to be lower during acute typhoid fever than after a course of antimicrobial therapy (P相似文献   
996.
AOPP-induced activation of human neutrophil and monocyte oxidative metabolism: A potential target forN-acetylcysteine treatment in dialysis patients. BACKGROUND: Oxidative stress largely contributes to hemodialysis-associated lethal complications, thus explaining the urgent need of antioxidant-based therapeutic strategies in hemodialysis patients. We previously identified advanced oxidation protein products (AOPP) in the uremic plasma as exquisite markers of oxidative stress and potent mediators of monocyte activation. The present study was aimed at searching whether (1) AOPP can also trigger activation of polymorphonuclear neutrophils (PMN), and (2) whether AOPP-induced activation could be inhibited by N-acetylcysteine (NAC), a widely used compound which has been shown to prevent oxidative injury to kidney. METHODS: Both human serum albumin (HAS) AOPP (i.e., HOCl-modified HSA in vitro preparations and AOPP extracted from plasma of hemodialysis patients) were tested for their capacity to trigger phagocyte nicotinamide adenine dinucleotide phosphate (NADPH) oxidase and myeloperoxidase (MPO)-dependent activities as measured by lucigenin- and luminol-amplified chemiluminescence (CL), respectively, as compared to receptor-dependent [opsonized zymosan or receptor-independent phorbol myristate acetate (PMA)]. The effect of PMN priming by platelet-activating factor (PAF), and the effect of NAC on normal monocyte and on normal or hemodialysis patient's (N = 16) PMN oxidative responses were compared. RESULTS: HSA-AOPP triggered in a HOCl dose-dependent manner both NADPH-oxidase- and MPO-dependent CL of PMN. This latter was further enhanced by PAF priming. Plasma-derived AOPP obtained from hemodialysis patients also triggered PMN respiratory burst. NAC significantly reduced HSA-AOPP-mediated responses of normal monocyte and of normal and uremic PMN but had no significant effect on opsonized zymosan- or PMA-induced CL responses. CONCLUSION: This dual potential of NAC to inhibit phagocyte oxidative responses induced by HSA-AOPP without affecting those mediated by compounds mimicking pathogens supports the proposal of a therapeutic trial with NAC aimed at reducing oxidative stress-related inflammation in hemodialysis patients.  相似文献   
997.
OBJECT: Convection-enhanced delivery (CED), the delivery and distribution of drugs by the slow bulk movement of fluid in the extracellular space, allows delivery of therapeutic agents to large volumes of the brain at relatively uniform concentrations. This mode of drug delivery offers great potential for the treatment of many neurological disorders, including brain tumors, neurodegenerative diseases, and seizure disorders. An analysis of the treatment efficacy and toxicity of this approach requires confirmation that the infusion is distributed to the targeted region and that the drug concentrations are in the therapeutic range. METHODS: To confirm accurate delivery of therapeutic agents during CED and to monitor the extent of infusion in real time, albumin-linked surrogate tracers that are visible on images obtained using noninvasive techniques (iopanoic acid [IPA] for computerized tomography [CT] and Gd-diethylenetriamine pentaacetic acid for magnetic resonance [MR] imaging) were developed and investigated for their usefulness as surrogate tracers during convective distribution of a macromolecule. The authors infused albumin-linked tracers into the cerebral hemispheres of monkeys and measured the volumes of distribution by using CT and MR imaging. The distribution volumes measured by imaging were compared with tissue volumes measured using quantitative autoradiography with [14C]bovine serum albumin coinfused with the surrogate tracer. For in vivo determination of tracer concentration, the authors examined the correlation between the concentration of the tracer in brain homogenate standards and CT Hounsfield units. They also investigated the long-term effects of the surrogate tracer for CT scanning, IPA-albumin, on animal behavior, the histological characteristics of the tissue, and parenchymal toxicity after cerebral infusion. CONCLUSIONS: Distribution of a macromolecule to clinically significant volumes in the brain is possible using convection. The spatial dimensions of the tissue distribution can be accurately defined in vivo during infusion by using surrogate tracers and conventional imaging techniques, and it is expected that it will be possible to determine local concentrations of surrogate tracers in voxels of tissue in vivo by using CT scanning. Use of imaging surrogate tracers is a practical, safe, and essential tool for establishing treatment volumes during high-flow interstitial microinfusion of the central nervous system.  相似文献   
998.
Background/Purpose: The aim of this study was to review the presentations of gastrointestinal duplication (GID) and to assess the influence of prenatal diagnosis on treatment. Methods: Retrospective review of all GID at 2 pediatric hospitals from 1980-2002 was conducted. Results: Seventy-three patients (M43:F30) were identified: 21 neonates, 28 infants (1 to 24 months), 15 children (1 to 10 years), 9 adolescents ([ge ]11 years). GID location by frequency was ileum (31.5%), ileocaecal valve (30.2%), duodenum (9.6%), stomach (8.2%), jejunum (8.2%), colon (6.8%), and rectum (5.5%). In neonates and infants, vomiting and distension were the most common presentations. Volvulus, caused by a duplication, occurred in 23.8% of neonates and caused the death of one neonate. Intussusception was identified in 10.9% of patients. In older children and adolescents, pain and vomiting were the most common associations. Six of these patients were being treated for Crohn[apos ]s disease, with the diagnosis of duplication made at laparotomy. Eighteen patients had a prenatal diagnosis by ultrasound scan, with 77.2% of these asymptomatic after birth. Most prenatal diagnoses occurred after 1991 (77.8%). When comparing an earlier period (1980 to 1991; 29 patients) with the current (1992 to 2002; 44 patients), a greater proportion of the latter patients were asymptomatic (36.4 v 13.8%) and had a lower incidence of complications (volvulus/intussusception). Conclusions: GID can lead to life-threatening complications. Prenatal diagnosis should lead to expeditious postnatal investigation and treatment before the onset of symptoms or complications. GID in older children can mimic Crohn[apos ]s disease. Laparoscopy/laparotomy should be considered in patients with atypical Crohn[apos ]s disease or when the diagnosis of an intraabdominal mass is unclear. J Pediatr Surg 38:740-744. [copy ] 2003 Elsevier Inc. All rights reserved.  相似文献   
999.
Self-selected walking speed is being increasingly used as a primary outcome measure in the management of neuromuscular disease. It would be useful if the speed recorded in the gait laboratory represented the child's walking speed in the community. This study investigated the difference in self-selected walking speeds between a 10-meter walk, as measured during instrumented gait analysis, and a 10-minute walk. The authors found that self-selected walking speed during the 10-minute walk was slower than the self-selected walking speed recorded during the 10-meter walk. The former may be more representative of walking speed in the community setting. Walking speed measured during walks of 10 minutes or more should become an integral part of gait laboratory evaluation.  相似文献   
1000.

Background  

Understanding health-related quality of life (HRQOL) leads to more effective and focused healthcare. America's growing health disparities makes it is increasingly necessary to understand the HRQOL of pregeriatric individuals who are now 55–64 years old, i.e. before they are eligible for federally mandated health care at age 65. Our study measured the self-perceived HRQOL of pregeriatric, poor patients with multiple chronic diseases treated at 2 public clinics.  相似文献   
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