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1.
A 69-year-old man was admitted to our kidney center with endstage renal failure. We started intermittent peritoneal dialysis immediately because of severe azotemia, hyperkalemia, and metabolic acidosis. Two weeks after admission, he developed uremic pericarditis with frequent ventricular premature contractions and supraventricular premature contractions. The intermittent peritoneal dialysis was then replaced by intensive hemodialysis, and oral administration of 300 mg/d of cibenzoline was started. Four days later, he developed thirst, weakness, and dyspnea due to respiratory muscular paralysis. We initiated respiratory support with a respirator because analysis of his blood gases revealed marked hypercapnia and hypoxia. He also developed hypoglycemia and prolonged PQ and QRS intervals on the electrocardiogram, which we believed were due to cibenzoline intoxication; we discontinued the cibenzoline immediately. All symptoms improved, and he was extubated 5 days later. After 2 months, his pericardial effusion disappeared. He now continues maintenance hemodialysis as an outpatient. We suspect that the cibenzoline induced the respiratory muscular paralysis for 2 reasons: 1) the patient experienced the respiratory muscular paralysis, at the same time he also experienced thirst, weakness, hypoglycemia, and prolonged PQ and QRS intervals on electrocardiogram, and all of these symptoms improved after the discontinuation of cibenzoline, and 2) his plasma concentration of cibenzoline became remarkably elevated, to 20 times above the standard therapeutic level. This patient's clinical course indicates that hemodialysis might be superior to intermittent peritoneal dialysis for treatment of cibenzoline intoxication.  相似文献   
2.
We describe a 53-year-old man with herpes simplex virus (HSV) brainstem encephalitis diagnosed based by positive HSV immunoglobulin M antibodies from cerebrospinal fluid. The MRI findings of this case had three unique features. First, the lesions were symmetrical. Second, the lesions may have been associated with reactivation of HSV infection in the region of the trigeminal nerve. Third, diffusion-weighted and apparent diffusion coefficient (ADC) imaging, conducted for the first time on an HSV brainstem encephalitis case, suggested that the lesions were associated with vasogenic edema.  相似文献   
3.
Skull metastasis of thyroid carcinoma is rare. The majority of skull metastases of thyroid carcinoma are of the follicular subtype, rather than thyroid papillary carcinoma. In this report, a 55-year-old woman with skull metastasis from thyroid papillary carcinoma is presented. The metastatic lesion of the skull was hypervascular and osteolytic, and the bleeding was profuse during resection. There have been only four reports of skull metastasis from thyroid papillary carcinoma. The mean period from the initial diagnosis of thyroid carcinoma until the detection of skull metastasis is 23.3 years, whereas in this patient, it was about 2 years. Therefore, in the clinical course of thyroid papillary carcinoma, skull metastasis should be considered, and the patient should be meticulously followed up.  相似文献   
4.
5.
Syncytia or multinucleated giant-cell formation is one of the major cytopathic effects induced by human immunodeficiency virus (HIV) infection. Cell fusion results from the strong interaction of CD4 molecules on the surface of the uninfected T cells and gp120, an external envelope glycoprotein of HIV on the infected T cells. We studied the production of HIV in fusion cells between MOLT-4 and virus-infected MOLT-4/HIV cells and found that HIV production was enhanced up to three- to fivefold, which showed a good correlation with the appearance and extent of syncytia formation. Blocking the fusion by monoclonal antibody against a binding epitope of CD4 molecule to gp120 decreased the HIV production significantly. Enhancement of HIV production was observed by more than five-fold in comparison with chronically infected cells, which were fusion free 20 hr postcocultivation. Electron microscopic observation also showed the presence of abundant HIV particles inside the fused cells and on the outer surface. AZT blocked the HIV augmentation of fused cells in coculture completely. Southern blot analysis revealed that both integrated and unintegrated HIV DNA were highly accumulated in fusion cells, as compared with fusion-free MOLT-4/HIV cells. Among unintegrated DNA, circular and linear DNA were accumulated to a similar degree. Northern blot hybridization showed that rapid enhancement of all three species of HIV-specific RNA containing genomic (9.2 kb) and subgenomic (4.3 and 1.9 kb) RNAs were found 20 hr postinfection in fusion cells. These data suggest that syncytia formation is an extremely active infection process of HIV, by which multiple rounds of reinfection might take place.  相似文献   
6.
Circulating autoantibodies are useful diagnostic markers of cancers and autoimmune diseases. Research over the past decade has resulted in some reports on the presence of autoantibodies against disease-related proteins such as annexin-I & II, recoverin and protein gene product 9.5 in the sera of patients with lung cancer, and also against calreticulin and alpha-enolase in autoimmune diseases. In this study, we first identified the a-enolase autoantibody in the sera of patients with lung adenocarcinoma by proteomics-based analysis. The comparison of two-dimensional polyacrylamide gel electrophoresis (2D-PAGE)/western blot (WB)/ECL detection revealed distinct distributions of antibodies in the sera of lung adenocarcinoma, tuberculosis and healthy subjects which reacted with soluble proteins derived from the adenocarcinoma A549 cell line. We found 16 spots in patients with adenocarcinoma by 2D-PAGE/WB/ECL detection and identified alpha-enolase, chaperonin, and other autoantibodies in the adenocarcinoma patients' sera. The specificities of an antibody against alpha-enolase was preliminarily observed in sera from 3 of 5 patients with adenocarcinoma, 0 of 10 patients with tuberculosis and 0 of 10 healthy subjects. In conclusion, we first identified alpha-enolase autoantibody in sera of lung adenocarcinoma and the autoantibody was seemed to be a specific marker of the lung adenocarcinoma. In addition, we also identified various autoantibodies in esophageal cancer, hepatocellular carcinoma, and non-Hodgkin's lymphoma. Moreover, we tried to identify the corresponding antigen of an unknown anti-cytoplasmic autoantibody, and an anti-red blood cell antibody by proteomics-based analysis. These antibodies might become new diagnosis markers.  相似文献   
7.
OBJECTIVES: We investigated the relationship between P16-immunostaining patterns and clinicopathological factors in early uterine cervix cancers and assessed whether P16-immunostaining patterns predict the prognosis of the patients with early uterine cervix cancers. METHODS: Twenty-nine early squamous cell carcinoma (SCC) specimens of the uterus were examined using immunohistochemistry for P16 expression. The P16-immunostaining pattern was classified into two groups: the homogeneous type and the heterogeneous type. P16-immunostaining patterns were evaluated in different parts of the carcinoma in situ (CIS): the center of the tumor and the front interface of the infiltrating tumor. RESULTS: All specimens were of the homogeneous type in CIS. The P16-immunostaining pattern was significantly of the heterogeneous type in the front interface of the infiltrating tumor with lymphatic invasion, vascular invasion, lymph node metastasis, and recurrence. Regarding the P16-immunostaining patterns in the front interface of the infiltrating tumor, the patients with the heterogeneous type showed a significantly worse prognosis than the patients with the homogeneous type. CONCLUSIONS: The prognosis of patients with early uterine cervical SCC may be predicted by evaluating the P16-immunostaining pattern in the front interface of the infiltrating tumor.  相似文献   
8.
Ubiquitin is thought to be a stress protein that plays an important role in protecting cells under stress conditions; however, its precise role is unclear. Ubiquitin expression level is controlled by the balance of ubiquitinating and deubiquitinating enzymes. To investigate the function of deubiquitinating enzymes on ischemia-induced neural cell apoptosis in vivo, we analyzed gracile axonal dystrophy (gad) mice with an exon deletion for ubiquitin carboxy terminal hydrolase-L1 (UCH-L1), a neuron-specific deubiquitinating enzyme. In wild-type mouse retina, light stimuli and ischemic retinal injury induced strong ubiquitin expression in the inner retina, and its expression pattern was similar to that of UCH-L1. On the other hand, gad mice showed reduced ubiquitin induction after light stimuli and ischemia, whereas expression levels of antiapoptotic (Bcl-2 and XIAP) and prosurvival (brain-derived neurotrophic factor) proteins that are normally degraded by an ubiquitin-proteasome pathway were significantly higher. Consistently, ischemia-induced caspase activity and neural cell apoptosis were suppressed approximately 70% in gad mice. These results demonstrate that UCH-L1 is involved in ubiquitin expression after stress stimuli, but excessive ubiquitin induction following ischemic injury may rather lead to neural cell apoptosis in vivo.  相似文献   
9.
To determine the late gestational development of copper-zinc (CnZn) and manganese (Mn) superoxide dismutases (SOD) in human lung, immunohistochemical localization was performed for each SOD. The lung samples were taken from five aborted fetuses, four fetuses in which intrauterine death occurred, one full-term neonate, two premature infants with hyaline membrane disease and one premature infant with bronchopulmonary dysplasia (BPD). Morphometry was performed, and the percent area of positive staining was computed. The bronchial epithelium was intensely stained from the early stages of gestation (i.e. 17 weeks), while the staining intensity for both CuZnSOD and MnSOD in the peripheral airways increased gradually during lung development. The mean percent area of the staining for CuZnSOD and MnSOD from 16 to 38 weeks was increased 30-fold and 8-fold, respectively, and further increases were observed postnatally. CuZnSOD staining was markedly decreased in lungs with respiratory disorders. However, proliferating type II pneumocytes were intensely stained for MnSOD in the BPD lungs, making the staining area 3-fold larger than that in the control lungs. These results clearly depict age-related increases in staining for both CuZnSOD and MnSOD and an alteration in SOD distribution associated with neonatal respiratory disorders.  相似文献   
10.
LIS1 is mutated in the human neuronal migration defect lissencephaly and along with NDEL1 (formerly NUDEL) participates in the regulation of cytoplasmic dynein function during neuronal development. Targeted disruption of Ndel1 suggested that NDEL1 could have other molecular targets that regulate microtubule organization for proper neuronal migration. To further understanding the molecular mechanism of LIS1 and lissencephaly, we identified the katanin p60 microtubule-severing protein as an additional molecular target of NDEL1. We demonstrate that phosphorylation of NDEL1 by Cdk5 facilitates interaction between NDEL1 and p60, suggesting that P-NDEL1 regulates the distribution of katanin p60. Abnormal accumulation of p60 in nucleus of Ndel1 null mutants supports an essential role of NDEL1 in p60 regulation. Complete loss of NDEL1 or expression of dominant negative mutants of p60 in migrating neurons results in defective migration and elongation of nuclear-centrosomal distance. Our results suggest that NDEL1 is essential for mitotic cell division and neuronal migration not only via regulation of cytoplasmic dynein function but also by modulation of katanin p60 localization and function.  相似文献   
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