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911.
Endotoxin-removal direct hemoperfusion column containing polymyxin B immobilized fibers (PMX-DHP) is an effective procedure for the treatment of sepsis-induced acute respiratory distress syndrome (ARDS). We investigated retrospectively the effects and appropriate timing of PMX-DHP induction for directly induced ARDS in 38 patients. PMX-DHP was carried out twice for two hours. Blood pressure, heart rate (HR) and PaO(2)/FIO(2) (PF) ratio, leukocytes, platelets, endotoxin, inflammatory cytokines and clusters of differentiated peripheral neutrophils and monocytes were measured before and after PMX-DHP. Acute Physiology and Chronic Health Evaluation (APACHE) II scores, Sequential Organ Failure Assessment (SOFA) scores and lung injury scores (LIS) were determined at the time of starting PMX-DHP. The underlying causes of ARDS were pneumonia in 29 patients and aspiration pneumonia in 9 patients. The patients were divided into Survivors (n = 21) and Nonsurvivors (n = 17). Mortality was 45% at 30 days after PMX-DHP. The APACHE II and SOFA scores and the LIS were not significantly different between the two groups. The time from the onset of ARDS to the start of PMX-DHP was significantly delayed between the two groups. PMX-DHP significantly improved the PF ratio, HR and systolic blood pressure in the Survivors compared to the Nonsurvivors. The function of active monocytes in the peripheral blood was significantly suppressed after PMX-DHP. This early induction of PMX-DHP is indicated for directly induced ARDS. In the Nonsurvivors, this delay could have led to undesirable responses to oxygenation and circulation after PMX-DHP.  相似文献   
912.
Neonatal onset multisystem inflammatory disease (NOMID), which is also known as chronic infantile neurological cutaneous and articular syndrome, is a rare disease that is characterized by the triad of cutaneous rash, chronic meningitis and arthropathy. The long-term prognosis is poor, with progressive deafness and visual impairment, and worsening of the central nervous system manifestations. Some fatal cases have been reported secondary to infection, vasculitis and amyloidosis. We recently managed a typical case of NOMID where the combined treatment of continuous hemodiafiltration and steroid pulse therapy was effective. The patient showed repeated flare ups of fever, arthralgia and meningitis accompanied with high levels of cytokines. The effect was temporary, but useful in recovery from such a serious condition.  相似文献   
913.
In the present study, we examined the effects of a new peritoneal dialysis fluid (PDF) with a low level of low glucose degradation products (GDP) on the functional and structural stability of the peritoneal membrane (PM). Male Sprague-Dawley rats were divided into three groups: group C (n = 8), without dialysate infusion; group P (n = 12), infused with low-level GDP solution (4.25% Physioneal, pH 7.0-7.4); and group D (n = 12), infused with conventional solution (4.25% Dianeal, pH 5.2, adjusted to pH 7.0). In groups D and P, animals were infused through a permanent catheter with 25 mL of PDF, twice daily for 8 weeks. Lipopolysaccharide was added into the PDF immediately before infusion on days 8, 9 and 10 in the two dialysis groups. When compared with group P, group D showed a higher glucose mass transfer at weeks 6 and 8, D/P urea at week 8, TGF-beta1 at weeks 4 and 8, and VEGF level at week 8. The submesothelial matrix layer of the parietal peritoneum was significantly thickened in group D and the lectin-stained blood vessels in this layer were well-visualized in group D compared with group P. There were significantly more peritoneal blood vessels in group D than group P. The transforming growth factor-beta induced gene-h3 (betaig-h3) and TGF-beta1 levels in the peritoneal effluent correlated with the submesothelial thickness, which correlated with the dialysate-to-plasma ratio (D/P) of protein and, inversely, with the rate of glucose transport (D/D(0) glucose, where D is glucose concentration in the dialysate and D(0) is glucose concentration in the dialysis solution before it is infused into the peritoneal cavity). The present study showed that low-GDP PDF effectively attenuated the peritoneal vascularization and fibrosis related to conventional solution.  相似文献   
914.
OBJECTIVE: Acute radiation of the small intestine causes an immediate and potentially reversible effect on the sensitive regenerative epithelium of the intestinal mucosa while markedly altering the overall intestinal ecosystem. The aim of the present study was test a novel probiotic mixture formulation (Microflorana‐F) in an experimental model of acute radiation enteritis with particular interest in endotoxinemia and bacterial translocation. MATERIALS AND METHODS: Male Wistar rats allocated to three groups were fed for 7 days with: (A) a standard balanced diet; (B) a standard diet with the addition of 1 mL t.i.d. of Microflorana‐F and (C) the same probiotic but after heat inactivation. Under ketamine anesthesia, abdominal irradiation was performed at a single dose rate of 20 Gy. Sham‐radiated healthy rats served as a control (D). Standard food and active/inactive probiotic supplementation schedule was maintained throughout the study period. When they were killed 14 days later a midline laparotomy and a medium sternotomy was carried out. The mesenteric lymph nodes, whole spleen and liver samples as well as blood, the portal vein and bile samples were cultured. Endotoxinemia was also measured. RESULTS: Early deaths (1 week) occurred mostly in rats fed standard food or inactivated probiotic. The endotoxin level significantly increased in irradiated rats fed standard food and inactivated probiotic while supplementation with the active form of the probiotic mixture significantly improved such parameters (P < 0.05). After radiation injury, mesenteric lymph nodes and portal blood were the samples most frequently yielding bacterial growth. Treatment with only the active form of probiotic significantly reduced the incidence of bacterial contamination in all samples. CONCLUSIONS: These data suggest that the manipulation of gut ecosystem by biologically effective probiotic preparations might be a worthwhile therapeutic and preventive tool in radiation‐induced enteritis.  相似文献   
915.
916.
The therapeutic potential of bone marrow-derived mesenchymal stem cells (BM-MSCs) has recently been explored in various pathological conditions of the central nervous system (CNS). However, the application of BM-MSCs in acutely induced Alzheimer's disease (AD) has not yet been reported. Herein the feasibility of using the BM-MSCs, as a therapeutic agent for AD has been tested. To assess this possibility, an acutely induced AD model induced by injecting amyloid-β (Aβ) into the dentate gyrus (DG) of hippocampus of C57BL/6 mice was used. Intracerebral transplantation of BM-MSCs into the brain of an induced AD model reduced their Aβ levels when compared to sham-transplanted animals. The diminution of Aβ deposits was accompanied by the activation of microglia. In addition, the activated microglia was located near the Aβ deposits, and their morphology was changed from ramified to ameboid as a sign of microglial phagocytosis. This study provides evidence that BM-MSCs can promote the reduction of Aβ through the microglial activation in this acutely induced AD brain, suggesting a potential therapeutic agent against AD.  相似文献   
917.
918.
目的 探究miR-30a-3p与NOD1的靶向关系,及其对心肌细胞缺氧复氧损伤的影响和机制。 方法 将细胞分为Ctrl组、H/R组、miR-30a-3p mimic组和miR-30a-3p inhibitor组,经过缺氧复氧处理后,转染相应的miRNA处理细胞,RT-PCR检测miR-30a-3p和NOD1基因表达水平,荧光素酶报告检测miR-30a-3p和NOD1靶向关系,Western blot检测NOD1、p-RPI2、p38 MAPK、NF-κB(p65)、cl-caspase-3蛋白表达水平,CCK8法检测细胞活性,Hoechst检测细胞凋亡,试剂盒检测LDH、CK、MDA、T-SOD水平。 结果 miR-30a-3p表达水平随缺氧复氧处理时间增长而下降,NOD1基因表达水平随缺氧复氧处理时间增长而升高。在荧光素酶报告实验中,NOD1 WT+miR-30a-3p mimic荧光素酶活性显著低于NOD1 WT+NC组。与Ctrl组比较,H/R组miR-30a-3p基因表达水平、细胞活性、T-SOD水平降低,NOD1、p-RPI2、p38 MAPK、NF-κB(p65)、cl-caspase-3蛋白表达水平、LDH、CK、MDA水平、细胞凋亡率升高;与H/R组比较,miR-30a-3p mimic组miR-30a-3p基因表达水平、细胞活性、T-SOD水平升高,NOD1、p-RPI2、p38 MAPK、NF-κB(p65)、cl-caspase-3蛋白表达水平、LDH、CK、MDA水平、细胞凋亡率降低,miR-30a-3p inhibitor组miR-30a-3p基因表达水平、细胞活性、T-SOD水平降低,NOD1、p-RPI2、p38 MAPK、NF-κB(p65)、cl-caspase-3蛋白表达水平、LDH、CK、MDA水平、细胞凋亡率升高。 结论 miR-30a-3p可靶向作用于NOD1,缓解心肌细胞缺氧复氧造成的损伤,其作用机制可能与调控NF-κB信号通路有关。  相似文献   
919.
A small physical change in the eye influences the entire neural information process along the visual pathway, causing perceptual errors and behavioral changes. Astigmatism, a refractive error in which visual images do not evenly focus on the retina, modulates visual perception, and the accompanying neural processes in the brain. However, studies on the neural representation of visual stimuli in astigmatism are scarce. We investigated the relationship between retinal input distortions and neural bias in astigmatism and how modulated neural information causes a perceptual error. We induced astigmatism by placing a cylindrical lens on the dominant eye of human participants, while they reported the orientations of the presented Gabor patches. The simultaneously recorded electroencephalogram activity revealed that stimulus orientation information estimated from the multivariate electroencephalogram activity was biased away from the neural representation of the astigmatic axis and predictive of behavioral bias. The representational neural dynamics underlying the perceptual error revealed the temporal state transition; it was transiently dynamic and unstable (approximately 350 ms from stimulus onset) that soon stabilized. The biased stimulus orientation information represented by the spatially distributed electroencephalogram activity mediated the distorted retinal images and biased orientation perception in induced astigmatism.  相似文献   
920.
Meningiomas are recognized as the most common late complication following radiotherapy. However, cytogenetic studies in childhood atypical radiation‐induced meningioma are sporadic, mainly because this condition generally occurs after a long latent period. In the present study we show the results of conventional and molecular cytogenetics in a 14‐year‐old boy with a secondary atypical meningioma. Apart from numerical changes, we found complex aberrations with the participation of chromosomes 1, 6 and 12. The invariable presence of loss of 1p was demonstrated by fluorescent in situ hybridization (FISH) analysis with probes directed to telomeric regions and by comparative genome hybridization (CGH). Previous cytogenetic studies on adult spontaneous and radiation‐associated meningiomas showed loss of chromosome 22 as the most frequent change, followed by loss of the short arm of chromosome 1. To the best of our knowledge this is the first report of highly complex chromosome aberrations in the pediatric setting of meningioma.  相似文献   
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