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991.
Production and functions of IL-17 in microglia   总被引:1,自引:0,他引:1  
Interleukin (IL)-17-producing helper T cells may play a pivotal role in the pathogenesis of multiple sclerosis. Here, we examined the effects of IL-17 on microglia, which are known to be critically involved in multiple sclerosis. Treatment with IL-17 upregulated the microglial production of IL-6, macrophage inflammatory protein-2, nitric oxide, adhesion molecules, and neurotrophic factors. We also found that IL-17 was produced by microglia in response to IL-23 or IL-1beta. Because microglia produce IL-1beta and IL-23, these cytokines may act in an autocrine manner to induce IL-17 expression in microglia, and thereby contribute to autoimmune diseases, such as MS, in the central nervous system.  相似文献   
992.
Abstract:  Since first being described in 1998, de novo autoimmune hepatitis (AIH) after liver transplantation has been reported in several cases suffering from non-autoimmune liver diseases and primary biliary cirrhosis (PBC). Glutathione S-transferase (GST) T1 genotype mismatches between donor and recipient have also been suggested to constitute a risk factor for de novo AIH. Here, we report a 33-yr-old woman who presented complaining of marked fatigue and jaundice four yr after living-donor liver transplantation for PBC. On examination, transaminase levels were highly elevated and ANA and antimitochondrial antibody M2 were positive. Histological findings showed zonal necrosis with lymphoplasmacytic infiltration closely resembling AIH. She had pretreatment AIH score of 16 and 19 points after relapse of de novo AIH. Two color fluorescence in situ hybridization with X and Y chromosome-specific probes clearly revealed that the hepatocytes were of donor origin and lymphocytes were of patient origin. The GSTT1 genotype of the patient and the donor were the same null type, suggesting that mechanisms other than GSTT1 mismatches may exist in de novo AIH development. In conclusion, recipient immune cells attacked the allogeneic transplanted liver of the patient via de novo AIH, although the exact participation of autoimmune mechanisms is unclear.  相似文献   
993.
Gallbladder cancer is a disease with poor prognosis, especially when it is associated with distant metastasis. Here we report a rare case of a patient with gallbladder cancer with extensive local and distant lymph node metastases and multiple liver metastases who has survived for more than 13 years through aggressive treatments. A 54-year-old woman developed right upper quadrant pain. Computed tomography (CT) revealed a papillary tumor in the gallbladder. Low-density tumors in segments 4, 5, and 8 of the liver and extensive paraaortic lymph node swelling were observed. She underwent central hepatic bisectionectomy and paraaortic lymphadenectomy. Two months later, hepatic metastases were found in segments 2, 3, 6, and 7, and percutaneous ethanol injection and transcatheter arterial chemoembolization were performed. Twelve months after the first surgery, CT revealed lymph node swelling around the right external iliac artery and behind the left renal vein. Metastatic lymph node dissection and resection and reconstruction of the right external iliac artery and vein with artificial graft replacements were performed. Two months later, CT revealed a paraesophageal lymph node swelling, which was treated by radiotherapy. At present, 13 years after the first surgery, and 11 years after the last radiotherapy, she is alive without any sign of recurrence.  相似文献   
994.
We used functional magnetic resonance imaging (fMRI) to determine whether neural activity can differentiate between true memory, false memory, and deception. Subjects heard a series of semantically related words and were later asked to make a recognition judgment of old words, semantically related nonstudied words (lures for false recognition), and unrelated new words. They were also asked to make a deceptive response to half of the old and unrelated new words. There were 3 main findings. First, consistent with the notion that executive function supports deception, 2 types of deception (pretending to know and pretending not to know) recruited prefrontal activity. Second, consistent with the sensory reactivation hypothesis, the difference between true recognition and false recognition was found in the left temporoparietal regions probably engaged in the encoding of auditorily presented words. Third, the left prefrontal cortex was activated during pretending to know relative to correct rejection and false recognition, whereas the right anterior hippocampus was activated during false recognition relative to correct rejection and pretending to know. These findings indicate that fMRI can detect the difference in brain activity between deception and false memory despite the fact that subjects respond with "I know" to novel events in both processes.  相似文献   
995.
Neuroimaging studies have demonstrated that the brain regions implicated in moral cognition. However, those studies have focused exclusively on violation of social norms and negative moral emotions, and very little effort has been expended on the investigation of positive reactions to moral excellence. It remains unclear whether the brain regions implicated in moral cognition have specific roles in processing moral violation or, more generally, process human morality per se. Using functional magnetic resonance imaging, brain activations during evaluation of moral beauty and depravity were investigated. Praiseworthiness for moral beauty was associated with activation in the orbitofrontal cortex, whereas blameworthiness for moral depravity was related to the posterior superior temporal sulcus. Humans might have developed different neurocognitive systems for evaluating blameworthiness and praiseworthiness. The central process of moral beauty evaluation might be related to that of aesthetic evaluation. Our finding might contribute to a better understanding of human morality.  相似文献   
996.
A 49-year-old man was admitted to our hospital with mild proteinuria. Prior to admission, he had been diagnosed as having Sjögren’s syndrome in association with primary biliary cirrhosis. Examination of a renal biopsy under light microscopy revealed diffuse and global mesangial cell proliferation and a spike and/or bubbling formation of the glomerular basement membrane (GBM), resembling membranoproliferative glomerulonephritis. In contrast, immunofluorescent studies showed marked immunoglobulin and complement depositions in the mesangial areas; however, only faint granular IgG and IgA deposition was observed along the GBM. Interestingly, electron microscopy revealed that a microtubular structure, derived from podocytes, was present in the GBM. We present a case of glomerulopathy showing podocytic infolding in association with Sjögren’s syndrome and primary biliary cirrhosis.  相似文献   
997.
Aim: Cot/Tpl2, a serine/threonine (Ser/Thr) protein kinase, has been classified as a member of the mitogen‐activated protein kinase (MAPK) family, and is known to have a pleiotropic role. Many studies have reported the involvement of Cot/Tpl2, mainly as a member of the Toll‐like receptor (TLR) 4 signalling pathway in lipopolysaccharide (LPS)‐induced tumor necrosis factor‐α (TNF‐α) production. At the same time, it is also related to the caspase‐dependent apoptotic pathway. Thus, the role of Cot/Tpl2 in ischaemia/reperfusion injury (IRI) in which TNF‐α and apoptosis are the major pathogenetic factors was studied. Methods: IRI was induced in wild type (Cot/Tpl2+/+) mice and in Cot/Tpl2‐deficient (Cot/Tpl2?/?) mice. The extent of tubular injury and renal function were studied. TNF‐α production, neutrophil infiltration and apoptosis were also compared between the two groups. Results: Cot/Tpl2?/? mice had preserved renal function compared with wild type mice in IRI. Although Cot/Tpl2 was phosphorylated in IRI and in the cultured tubular epithelial cells (TEC) after stimulation with LPS and hydrogen peroxide, there were no significant differences in terms of TNF‐α production, neutrophil infiltration or MAPK activation between Cot/Tpl2+/+ and Cot/Tpl2?/? mice. In contrast, Cot/Tpl2?/? mice showed obviously reduced terminal deoxynucleotidyl transferase‐mediated dUTP nick end labelling positive cells and cleaved caspase‐3 positive cells. Furthermore, Cot/Tpl2‐deficient TECs demonstrated significantly less caspase‐3 activation after hydrogen peroxide stimulation with comparable caspase‐9 activation to wild type TEC. Conclusion: Cot/Tpl2 did not function as a member of MAPK family, but as a promoter of apoptosis in IRI. These results suggest that Cot/Tpl2 could be a possible therapeutic target in IRI.  相似文献   
998.
Gliogenesis is an important component of cortical development during the postnatal period. Two macroglial cells are generated in a particular order, i.e. astrocytes first and oligodendrocytes later. The mechanisms underlying this sequence of glial differentiation are unknown but interactions with blood vessels are postulated to play a role. We show, using a mouse in-vitro coculture system, that endothelial cells promote astrocyte differentiation but inhibit oligodendrocyte differentiation of postnatal cortical progenitors. Endothelial cells produce bone morphogenetic proteins (BMPs) to activate Sma- and Mad-related protein (Smad) signalling in progenitors and the effects of endothelial cells on glial differentiation are blocked by the BMP antagonist Noggin. Differentiation of progenitors into astrocytes results in the inhibition of endothelial cell growth, accompanied by changes in gene expression of angiogenic factors, indicating bidirectional interactions between progenitors and endothelial cells. In vivo , Smad signalling is activated in various types of cortical cells including progenitors in association with astrogenesis but is inactivated before the peak of oligodendrogenesis. Capillary vessels isolated from the developing cortex express high levels of BMPs. Together, these results demonstrate that endothelial cells regulate glial differentiation by secreting BMPs in vitro and suggest a similar role in cortical gliogenesis in vivo .  相似文献   
999.
1000.
The prognosis of patients with bone metastasis from lung cancer has not been well documented. We assessed the survival rates after bone metastasis and prognostic factors in 118 patients with bone metastases from lung cancer. The cumulative survival rates after bone metastasis from lung cancer were 59.9% at 6 months, 31.6% at 1 year, and 11.3% at 2 years. The mean survival was 9.7 months (median, 7.2 months; range, 0.1-74.5 months). A favorable prognosis was more likely in women and patients with adenocarcinoma, solitary bone metastasis, no metastases to the appendicular bone, no pathologic fractures, performance status 1 or less, use of systemic chemotherapy, and use of an epithelial growth factor receptor inhibitor. Analyses of single and multiple variables indicated better prognoses for patients with adenocarcinoma, no evidence of appendicular bone metastases, and treatment with an epithelial growth factor receptor inhibitor. The mean survival period was longer in a small group treated with an epithelial growth factor receptor inhibitor than in the larger untreated group. The data preliminarily suggest treatment with an epithelial growth factor receptor inhibitor may improve survival after bone metastasis.  相似文献   
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