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51.
Sporadic amyotrophic lateral sclerosis is an idiopathic human degenerative disease of spinal cord and brain motor neurons. Prior studies demonstrated that most patients with amyotrophic lateral sclerosis posses immunoglobulins that bind to purified L-type voltage-gated calcium channels, that titers of anti–voltage-gated calcium channel antibodies correlate with disease progression rates, and that amyotrophic lateral sclerosis patient-derived antibodies (ALS IgG) produce electrophysiological changes in the function of voltage-gated calcium channels. Using Western transfer immunoblots and enzyme-linked immunosorbent assays, the calcium ionophore–forming α1 subunig of the voltage-gated calcium channel is now identified as the major voltage-gated calcium channel antigen to which ALS IgG binds. Additionally, the binding of an L-type voltage-gated calcium channel α1 subunit–directed monoclonal antibody, which itself mimics the effects of ALS IgG on skeletal muscle voltage-gated calcium channel currents, is selectively prevented by preaddition of ALS IgG. Voltage-gated calcium channel–binding IgG from patients with Lambert-Eaton myasthenic syndrome appears to be differentiated from ALS IgG by the reactivity of the former to both α1 and β subunits of the calcium channel. These assays provide further evidence linking amyotrophic lateral sclerosis to an autoimmune process, and suggest one means to differentiate immunoglobulins from patients with amyotrophic lateral sclerosis from those of patients with another autoimmune disease expressing calcium channel antibodies.  相似文献   
52.
A 72-year-old man with recurrent pancreatitis and a horseshoe-shaped anomaly of the pancreas is described. The diagnosis was made by endoscopic retrograde cholangiopancreatography (ERCP) and computed tomography scan; laparotomy was confirmatory. The abnormal duct branched to the lower left from an enlarged Santorini's duct; a thin Wirsung's duct was joined at its distal portion to the junction of the abnormal duct. The anomaly was associated with a cystic dilatation of the common bile duct with stone and cholecystolithiasis. This anomaly is considered to be a variation of the dominant dorsal duct syndrome.  相似文献   
53.
Beta-core fragment (beta-CF), a fragment of the hCG beta-subunit missing its carboxyterminal peptide, can be detected in the urine of women throughout pregnancy or in trophoblastic disease. It is also found in the urine of patients with nontrophoblastic cancers. We examined the beta-CF level in urine samples from patients with cervical cancer and assessed its value as a tumor marker. beta-CF was measured by an enzyme immunoassay with hCG beta-core directed monoclonal antibody No. 229. Based on the cut-off value (0.2ng/ml) from control subjects, the overall positivity rate for urinary beta-CF in the cervical cancer group was 45% (57 of 128 patients), increasing from 32% (23 of 73) in stage I to 100% (2 of 2) in stage IV. These positivity rates exceeded or equaled those of the other markers, SCC, CEA, CA19-9 and CA125, simultaneously measured in the patients' serum. There was no significant difference between the positivity rates for the two histological types of cancer, squamous cell carcinoma and adenocarcinoma. Serial determination in 28 patients with increased urinary beta-CF prior to therapy showed that 24 patients had a decreased concentration after successful treatment, but 2 of 4 patients with still increased urinary beta-CF during or after treatment subsequently relapsed. The determination of urinary beta-CF may provide a useful tool in monitoring the response to treatment in patients with cervical cancer.  相似文献   
54.
The colonic mucosa of 30 patients with ulcerative colitis was analyzed by an immunohistochemical technique. A quantitative evaluation for lymphocyte subsets show significantly increased numbers of CD3+, CD4+, CD8+, and CD28+ cells in ulcerative colitis cases of histological grades 3, 4 and 5 by Matts' classification comparing to normal control cases. CD4/CD8 ratio in each histological grade of ulcerative colitis was not significantly different from those in normal controls and disease controls (infectious colitis cases). However, CD28/CD3 ratio was increased significantly in ulcerative colitis cases of histological grades 3, 4 and 5 comparing to control cases. Most of the lymphocytes were positive for lymphocyte function-associated antigen-1 alpha (LFA-1 alpha). There were increased numbers of S100-beta + dendritic cells and CD68+ macrophages in the luminal area of the lamina propria. Moreover double stainings revealed that most of the S100-beta + dendritic cells and CD68+ macrophages were intercellular adhesion molecule-1 (ICAM-1, a ligand for LFA-1) positive. These findings suggested that the expression of ICAM1 on S100-beta + dendritic cells and CD68+ macrophages is important by the interaction with T cells and T cell antigen recognition.  相似文献   
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56.
We investigated the effects of mild and non-lethal ischemic insult on neuronal death following subsequent lethal ischemic stress in various brain regions, using a gerbil model of bilateral cerebral ischemia. Single 10-min ischemia consistently caused neuronal damage in the hippocampal CA1, CA2, CA3 and CA4, layer III/IV of the cerebral cortex, dorsolateral part of the caudoputamen and ventrolateral part of the thalamus. On the other hand, in double ischemia groups, 2-min ischemic insult 2 days before 10-min ischemia exhibited significant protection in the CA1 and CA3 of the hippocampus, the cerebral cortex, the caudoputamen and the thalamus. Five-min ischemic insult 2 days before 10-min ischemia also showed protective effect in the same areas as those of 2-min ischemia except for the CA1 region of the hippocampus, while 1-min ischemic insult exhibited no protective effect in any brain regions. In the immunoblot analysis, both 2- and 5-min ischemia caused increased synthesis of heat shock protein 72 (HSP 72) in the hippocampus, but 1-min ischemia did not. The present study demonstrated that the ‘ischemic tolerance’ phenomenon was widely found in the brain and also suggested that ischemic treatment severe enough to cause HSP 72 synthesis might be needed for induction of ‘ischemic tolerance’.  相似文献   
57.
A 69-year-old man was admitted to hospital because of sustainedventricular tachycardia with right bundle branch block morphology.After abolition of ventricular tachycardia, an electrocardiogramshowed atrial fibrillation, complete right bundle  相似文献   
58.
Fuzzy theory was applied to the rate control of a cardiac pacemaker which uses two parameters, respiratory rate and temperature, as the parameters for rate regulation. Using 25 fuzzy reasoning rules derived from five mongrel dogs, the pacing rates in three animals were calculated and compared with the intrinsic heart rates. It is concluded that the fuzzy method is well suited for the rate determination of a multi-parameter rate-responsive cardiac pacemaker.  相似文献   
59.
60.
We found that a chemokine receptor gene, CCR1, acts downstream of NFAT2 in RANKL-stimulated RAW264 and bone marrow cells. The upstream regulatory region of CCR1 showed RANKL-dependent and CsA-suppressible promoter activity. Downregulation of the expression and function of CCR1 suppressed cell migration. INTRODUCTION: We previously reported that the expression of NFAT2 induced by RANKL is a key process for progression to multinucleated cells in an in vitro osteoclastogenesis system. Identifying the target genes of NFAT2 would thus be informative about the differentiation process. We focused here on chemokine and chemokine receptor genes that act downstream of NFAT2 in RAW264 cells as well as osteoclast precursors prepared from bone marrow cells. MATERIALS AND METHODS: RAW264 mouse monocyte/macrophage line cells were cultured with or without cyclosporin A (CsA) in the presence of RANKL or glutathione S-transferase (GST). Osteoclast precursors were prepared from bone marrow cells. RANKL-inducible and CsA-suppressible genes were searched for by microarray analysis, and expression was confirmed by quantitative RT-PCR. Promoter activity was measured by luciferase gene reporter assay. Short interfering (si)RNA for CCR1 was introduced in RAW264 cells. Cell migration activity was examined using a Boyden chamber assay. RESULTS AND CONCLUSIONS: We identified the chemokine receptor gene CCR1 as a gene showing significant differential expression profiles in osteoclastogenesis in the presence versus the absence of CsA, an inhibitor of NFAT. This property was unique to CCR1 among the chemokine and chemokine receptor genes examined in both RAW264 and bone marrow cells. The upstream regulatory region was isolated from CCR1, and its RANKL-dependent and CsA-suppressible promoter activity was confirmed. The functional significance of CCR1 was assessed by monitoring the migration of cells in a transwell migration assay, and this activity was abolished when either CsA- or CCR1 siRNA-treated cells were used. Moreover, treatment with a Galpha inhibitor pertussis toxin (PTX) or methiolynated-regulated on activation, normal T cells expressed and secreted (Met-RANTES), an antagonist of CCR1, suppressed multinucleated cell formation in the bone marrow cell system. Together, these results suggest that the CCR1 signaling cascade is under the control of NFAT2 and seems to enhance the migration of differentiating osteoclasts.  相似文献   
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