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151.
Background and aimsActivation of the pro-inflammatory and anti-inflammatory cytokine cascade, including tumour necrosis factor (TNF)-alpha and interleukin (IL)-4, is considered to play an important role in severe liver injury. Kupffer cells, resident macrophages of the liver, activated with lipopolysaccharide (LPS) release pro-inflammatory cytokine. d-Galactosamine (d-GalN), a hepatocyte-specific inhibitor of RNA synthesis, is known to sensitise animals to the lethal effects of LPS. In the present study we seek to reverse some altered parameters, immunological and histopathological, to normal values of rats pre-treated with garlic.MethodsAcute hepatic failure was induced in male albino rats by the intraperitoneal injection of 500 mg d-GalN and 50 μg LPS/kg body weight. Expression levels of TNF-α and IL-4 were detected by ELISA. Leukocytes proliferation was carried out by differential count. For histopathology, liver sections were stained with haematoxylin and eosin. Data were analysed by SPSS program version 13.0.ResultsThe data showed significant increase in the numbers of granulocytes, but with significant decreases in lymphocyte and monocytes proliferation and the TNF-alpha and IL-4 levels in d-GalN/LPS-induced group. Garlic pre-treatment of liver-injured rats induced significant amelioration in the numbers of monocytes and lymphocytes, with significant increase in granulocytes numbers, TNF-α level and IL-4 level.ConclusionsResults of this study revealed that garlic could afford a significant protection in the alleviation of d-GalN/LPS-induced hepatocellular injury. 相似文献
152.
Strous RD Maayan R Lapidus R Goredetsky L Zeldich E Kotler M Weizman A 《Schizophrenia Research》2004,71(2-3):427-434
Dehydroepiandrosterone (DHEA) is a major circulating neurosteroid in humans and its administration has demonstrated efficacy in the improvement of mood, with increased energy, interest, confidence and activity levels. Since recent findings have suggested the role of neurosteroids in general, and DHEA in particular, in the symptomatology and pharmacotherapy of schizophrenia patients with chronic illness, we investigated DHEA and DHEA-S blood levels in individuals in their first-episode of psychosis in order to exclude effects of age, chronic illness, long-term treatment and institutionalization. Blood levels for DHEA, DHEA-S and cortisol were obtained for 37 first-episode schizophrenia subjects and 27 normal age- and sex-matched controls and correlated with a range of clinical and side-effect rating scales. Baseline DHEA and DHEA-S levels were significantly higher in schizophrenia patients (p<0.05 and p<0.001, respectively). No gender differences were noted in DHEA levels; however, DHEA-S levels were significantly higher in male patients. DHEA-S levels inversely correlated with severity of illness (p<0.05) and aggressive behavior (p<0.05). Patients with higher DHEA-S levels tended to have shorter hospitalizations. Results suggest that individuals in their first-episode of schizophrenia psychosis may develop a neurosteroid response to the first onset of psychosis, which may be associated with a reduction in various adverse clinical features including aggression. Such a putative mechanism may become desensitized with the onset of chronic illness. While preliminary, these results further imply the role of these neurosteroids in the pathophysiology and management of schizophrenia. 相似文献
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154.
Dimitrios Tzanis Nairuthya Shivathirthan Alexis Laurent Mohammad Abu Hilal Olivier Soubrane Airazat M. Kazaryan Giuseppe Maria Ettore Ronald M. Van Dam Panagiotis Lainas Hadrien Tranchart Bjorn Edwin Giulio Belli Ricardo Robles Campos Neil Pearce Brice Gayet Ibrahim Dagher 《Journal of hepato-biliary-pancreatic sciences》2013,20(2):120-124
Background/purpose
Laparoscopic hepatectomies have seen a worldwide proliferation. Major anatomic resections, which were initially considered unsuitable for laparoscopy, are currently confined to a few centers of expertise. The aim of this study was to discuss the current trends and techniques in laparoscopic major hepatectomy in Europe.Methods
The prospective databases of ten European centers were combined to provide answers to a questionnaire that had been addressed to all European teams known to perform laparoscopic liver surgery.Results
Between 1996 and 2011 a total of 2245 laparoscopic liver resections have been carried out, of which 495 (22 %) were major resections. The proportion of laparoscopic right and left hepatectomies varied between 4 and 40 % of all major hepatectomies of the same type. Benign, primary malignant and metastatic lesions were, respectively, 22.4, 19.6 and 58 % of all indications. The different techniques and approaches, as regards hand assistance, hepatic inflow and outflow control, liver mobilization and concomitant colectomies, are discussed.Conclusions
To date, an important level of experience of laparoscopic liver resection has been accumulated in Europe, and experience of major hepatectomies is constantly increasing. However, they remain technically very demanding procedures which should be confined to expert surgeons who have already acquired considerable experience with simpler laparoscopic liver resections. 相似文献155.
156.
157.
158.
The aim of this study was to visualize, at the ultrastructural level, the deformation and failure mechanism of cartilage matrix in the tensile mode. Full-thickness dumbbell-shaped specimens were prepared from adult bovines. There were two specimen groups; in the 'parallel' group the specimen axis was parallel to the split lines defining the preferential orientation of the collagen in the articular surface, and in the 'perpendicular' group the specimen axis was perpendicular to the split lines. Specimens were placed with the articular surface uppermost and subjected to a graded series of strain within individual mini-tension devices, while observed with stereomicroscopy and confocal laser scanning microscopy. Thereafter, the changes in the ultrastructure were observed with both scanning and transmission electron microscopy. The mechanism of cartilage failure in the tensile mode comprised the following stages, whether the strain was applied parallel or perpendicular to the split line. (1) At 0% strain a fibrillar meshwork within the articular surface was predominantly orientated in the direction of the split line. (2) As strain increased, the fibrillar meshwork became more orientated in the parallel group and reorientated in the perpendicular group in the direction of the applied strain. (3) After complete reorientation of the fibrillar meshwork in the direction of the applied strain, the initial sign of failure was rupture of the fibrillar meshwork within the articular surface. (4) Subsequently, the rupture rapidly propagated into the deeper layers. Greater strains were required for fibrillar reorientation and complete rupture in the 'perpendicular group' than in the parallel group. 相似文献
159.
Rueda B Fernandez-Gutierrez B Balsa A Pacual-Salcedo D Lamas JR Raya E Gonzalez-Gay MA Martin J 《Tissue antigens》2008,72(3):206-210
The aim of this study was to investigate the CD69 gene as a new functional candidate gene for rheumatoid arthritis (RA) genetic predisposition. A case–control association study including 933 RA patients and 800 healthy individuals was conducted. Five haplotype-tagging single nucleotide polymorphisms (SNPs) (rs929615, rs3176806, rs4763299, rs11052877, and rs3176789) covering the CD69 gene coding, 5' and 3' untranslated regions were selected as CD69 genetic markers and genotyped using a Taqman 5' allelic discrimination assay. No statistically significant differences were observed in the single marker association study with regard to either genotypic or allelic frequencies when considering the rs929615, rs3176806, rs4763299, rs11052877, and rs3176789 CD69 SNPs independently. According to these findings, no statistically significant skewing was observed between the RA patients and the controls in the distribution of CD69 haplotypes. In summary, our results do not support a major role for the CD69 gene polymorphisms in RA genetic predisposition in our population. 相似文献
160.
The Francisella tularensis-containing phagosome (FCP) matures to a late-endosome-like phagosome prior to bacterial escape into the cytosols of macrophages, where bacterial proliferation occurs. Our data show that within the first 15 min after infection of primary human monocyte-derived macrophages (hMDMs), approximately 90% of the FCPs acquire the proton vacuolar ATPase (vATPase) pump and the lysomotropic dye LysoTracker, which concentrates in acidic compartments, similar to phagosomes harboring the Listeria monocytogenes control. The acquired proton vATPase pump and lysomotropic dye are gradually lost by 30 to 60 min postinfection, which coincides with bacterial escape into the cytosols of hMDMs. Colocalization of phagosomes harboring the iglD mutant with the vATPase pump and the LysoTracker dye was also transient, and the loss of colocalization was faster than that observed for the wild-type strain, which is consistent with the faster escape of the iglD mutant into the macrophage cytosol. In contrast, colocalization of both makers with phagosomes harboring the iglC mutant was persistent, which is consistent with fusion to the lysosomes and failure of the iglC mutant to escape into the macrophage cytosol. We have utilized a fluorescence microscopy-based phagosome integrity assay for differential labeling of vacuolar versus cytosolic bacteria, using antibacterial antibodies loaded into the cytosols of live hMDMs. We show that specific inhibition of the proton vATPase pump by bafilomycin A1 (BFA) blocks rapid bacterial escape into the cytosols of hMDMs, but 30% to 50% of the bacteria escape into the cytosol by 6 to 12 h after BFA treatment. The effect of BFA on the blocking of bacterial escape into the cytosol is completely reversible, as the bacteria escape after removal of BFA. We also show that the limited fusion of the FCP to lysosomes is not due to failure to recruit the late-endosomal fusion regulator Rab7. Therefore, within few minutes of its biogenesis, the FCP transiently acquires the proton vATPase pump to acidify the phagosome, and this transient acidification is essential for subsequent bacterial escape into the macrophage cytosol. 相似文献