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31.
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Activation of the amyloid beta-protein precursor, secretary pathway through alpha-secretase has been reported to increase the secretion of neuroprotective amyloid precursor protein and preclude the formation of amyloid beta-protein. Activation of protein kinase C has been shown to accelerate this secretory pathway. These results prompted us to focus on a potential links between protein kinase C and the amyloid beta-protein-related pathology of Alzheimer disease (AD). Although protein kinase C is reported to occur in senile plaques, its catalytic activity has not been investigated. As the phosphorylation of myristoylated alanine-rich C kinase substrate (MARCKS) has been used as a marker for activation of protein kinase C in vivo, we examined its phosphorylation in brain tissues obtained from seven AD patients and five non-demented subjects using an antibody that specifically recognized MARCKS phosphorylated by protein kinase C. Phosphorylation of MARCKS in cortical neurons in AD brains was weaker than that in control brains. Interestingly, however, phosphorylation of MARCKS was detected in microglia and dystrophic neurites within neuritic plaques, a mature form of amyloid beta-protein deposits. These results suggest that protein kinase C alteration is associated with AD pathology and that protein kinase C is activated in microglia and dystrophic neurites by amyloid beta-protein in AD brains.  相似文献   
33.
Late onset X-linked hydrocephalus with normal cerebrospinal fluid pressure   总被引:1,自引:0,他引:1  
A family with X-linked hydrocephalus with normal cerebrospinal fluid (CSF) pressure and in which three brothers and a grandson of case 1, a proband, were affected is reported. The symptoms at onset were epileptic attacks that started in adulthood in the three brothers and at the age of 6 years in the grandson. In the three brothers, from 10 to 27 years after the onset of epileptic episodes, disorganization of intelligence and psychiatric deterioration were gradually noticed by their families. At the same time, they showed occasional urinary incontinence. Brain computed tomography (CT) scans revealed dilatation of the ventricular systems. Based on the results of the measurement of CSF pressure and radioactive-iodinated human serum albumin (RISA)-cysternography, two of the brothers were diagnosed as having normal pressure hydrocephalus (NPH), and they were treated neurosurgically. However, no obvious improvement in clinical symptoms was observed. Although the grandson had shown normal psychomotor development during his early childhood, temporal epilepsy and temper tantrums started at the age of 6 years. Computed tomography-scanning revealed dilatation of the ventricular system similar to the other three cases at the age of 8 years. With the diagnosis of NPH, the patient underwent a shunt operation, which resulted in no obvious effects. As it is reasonable to surmise that the pathological gene would have been transferred via the daughter of the proband to the grandson, it is suggested that the inheritance manner might be X-linked recessive. The cases presented here are different from the cases of hydrocephalus due to stenosis of the aqueduct Sylvius (HSAS) and other types of X-linked hydrocephalus reported previously in terms of the age of onset, course, symptoms, and CT findings. Thus, it is suggested that the present cases might be a new type of X-linked hydrocephalus.  相似文献   
34.
Some aspects of the culture-bound syndrome are presented for discussion. From the psychiatric and medical anthropological viewpoints, kamidaari is described as an initiatory illness for seeing a shaman, and focus on clinical realities developing between different therapeutic subcultures in the same culture and the complementary practices of two epistemological ones, namely, the shamanistic and modern psychiatric system in the shamanistic climate. It is suggested that the culture-bound syndrome that reflects cultural influences on disease patterns and renders them difficult to place in a universal classificatory system should be seen as a vernacular bricolage or as tactics used by people within the web of their own local culture of origin. Therapists who treat patients in a cross-epistemological milieu should be aware of the subcultural-epistemological issues that may affect the clinical process. It should be recognized that, depending on the nature of a particular psychiatric crisis, the clinical encounter is straddling the boundaries of multiple clinical realities. At every stage in the clinical field, there is an intersection, consonance, or interruption of rejoinders in the open dialog by all those engaged in the clinical time. Aspects of climatic, culturally sensitive psychotherapy will be described, and the concept of the culture-bound syndrome will be reconsidered. Our approach could be seen as 'situation- and fudo-bound'.  相似文献   
35.
Objective To examine the continuation of antibody prevalence status after 12 months and background factors in antibody-positive subjects following asymptomatic infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Methods We initially determined the SARS-CoV-2 anti-nucleocapsid protein immunoglobulin G (anti-N IgG) antibody prevalence in 1,603 patients, doctors, and nurses at 65 medical institutions in Kanagawa Prefecture, Japan. We then obtained consent from 33 of the 39 subjects who tested positive and performed follow-up for 12 months. Results Follow-up for up to 12 months showed that a long-term response of the anti-N IgG antibody could be detected in 6 of the 33 participants (18.2%). The proportions with hypertension, using an angiotensin-receptor blocker, and without a drinking habit were higher among the participants with a long-term anti-N IgG antibody response for up to 12 months than among those without a long-term antibody response. Conclusions The proportion of individuals with subclinical COVID-19 who continuously had a positive result for the anti-N IgG antibody at 12 months was low.  相似文献   
36.
37.

Background

Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is an established procedure for the pathological diagnosis of gastrointestinal submucosal tumors (SMTs). Although bleeding and perforation are potentially severe complications of EUS-FNA, the incidences and severities of these complications have not yet been fully evaluated because of their relative rarity.

Aim

The purpose of this study was to evaluate the incidences and mortality of severe bleeding and perforation in patients who underwent EUS-FNA for SMTs.

Methods

The records of 1,135 consecutive patients who underwent EUS-FNA for SMTs at 219 hospitals, with low- to high-volume, were reviewed using a Japanese nationwide administrative database.

Results

Of the targeted lesions 73.5 % were located in the stomach, 13.4 % in the esophagus, 8.2 % in the duodenum, and 4.9 % at other sites. Five patients (0.44 %) experienced severe bleeding requiring red blood cell transfusion or endoscopic treatment, with none experiencing perforation. Only one patient (0.09 %) died in-hospital within 30 days of EUS-FNA (0.09 %), with death not associated with bleeding or perforation.

Conclusions

EUS-FNA is safe in evaluating SMTs, with low risks of bleeding and perforation.  相似文献   
38.
39.
High sensitivity of a novel ELISA for anti-M2 in primary biliary cirrhosis   总被引:8,自引:0,他引:8  
The use of an ELISA for the detection of anti-M2, a specific autoantibody in primary biliary cirrhosis (PBC), has been common in Japan. However, there are some problems in the sensitivity of this ELISA, especially in PBC patients showing antimitochondrial antibody (AMA)-negative sera or low AMA titers by immunofluorescence. Recently, a new ELISA for anti-M2 was developed, using porcine heart mitochondrial protein as the antigen. We report here comparative studies of the new and the former anti-M2 ELISAs. Porcine heart mitochondrial protein was prepared and used as the antigen for the new ELISA for anti-M2. Sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of this protein showed three major M2 antigen proteins. As the second antibody, peroxidase-conjugated anti-human mouse monoclonal IgM, in addition to monoclonal IgG, was included. The sera of 171 PBC patients were examined. As controls, we examined the sera of 167 non-PBC patients and the sera of 115 normal controls. The cut-off index was set at 10 U/ml, based on the results for the normal controls. No sera from the non-PBC patients or the normal controls were positive for anti-M2 by either the new or the former ELISA. However, the positivity rate for anti-M2 in PBC patients with the new ELISA was 78%; in contrast, that with the former ELISA was only 54%; this difference was significant (P = 0.00001). In particular, in 65 patients showing AMA titers of 1 : 20 or less, the positivity rate with the new ELISA was 51%; in contrast, that with the former ELISA was only 17%. As the sensitivity of the new ELISA is significantly higher than that of the former ELISA, especially for sera from patients showing AMA-negativity or low titers of AMA, the new ELISA is considered to be more effective than the former ELISA for use in anti-M2 screening assays in patients with PBC. Received: May 17, 2000 / Accepted: September 1, 2000  相似文献   
40.
Yellow fever virus (YFV) causes 30,000 deaths worldwide, despite the availability of a vaccine. There are no approved antiviral therapies for the treatment of YFV disease in humans, and, therefore, these studies were designed to investigate the anti-YFV properties of T-1106, a substituted pyrazine, in a hamster model of YFV disease. Intraperitoneal (i.p.) treatment with 100 mg/kg of body weight/day of T-1106 starting 4 h prior to virus inoculation and continuing twice daily through 7 days post-virus inoculation (dpi) resulted in significantly improved survival, alanine aminotransferase levels in the serum, weight gain, and mean day to death. Virus titer in the liver at 4 dpi was significantly reduced in treated animals, as determined by both quantitative real-time PCR and infectious cell culture assay. No toxicity (weight loss or mortality) was observed at a dose of 100 mg/kg/day in sham-infected control animals. The observed minimal effective dose of T-1106 was 32 mg/kg/day administered either by oral or i.p. treatment. Therapeutic treatment was effective in significantly improving survival when T-1106 was administered beginning as late as 4 days after virus challenge with twice-daily treatment for 8 days at a dose of 100 mg/kg/day. With favorable safety, bioavailability, and postviral challenge treatment efficacy, T-1106 was effective in the treatment of disease in hamsters infected with YFV and should be further studied for potential use as a therapy for human YFV disease.  相似文献   
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