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61.
A monoclonal antibody (MAbIII604) specific to phenolic glycolipid Tb (PGL-Tb), a Mycobacterium tuberculosis-specific antigen, was produced and used in the detection of the antigen. MAbIII604 reacted with the PGL-Tb antigen but not with other phenolic glycolipids from Mycobacterium leprae, M. bovis, and M. kansasii, thus indicating the specificity of the monoclonal antibody to PGL-Tb. A dot enzyme-linked immunosorbent assay with MAbIII604 was employed to detect the PGL-Tb antigen in lipids purified from M. tuberculosis clinical isolates. Of 50 isolates, 32 (64.0%) showed clear evidence of the PGL-Tb antigen by the dot enzyme-linked immunosorbent assay, but there were marked variations in the intensities and sizes of spots. This suggests differences in PGL-Tb antigen production among M. tuberculosis strains even when they are grown in the same culture media and conditions. This was most evident from the fact that in only eight (16.0%) of the isolates examined was the PGL-Tb antigen detectable by thin-layer chromatography, which is much less sensitive for the detection of glycolipid antigens. This study shows that monoclonal antibodies specific to PGL-Tb are useful in detecting the antigen in lipid extracts and that there is a marked variation in the PGL-Tb production among M. tuberculosis clinical isolates.  相似文献   
62.
Following horseradish peroxidase (HRP) injection into the cephalopharyngeal muscle (CeP), the hyopharyngeal muscle (HP), the thyropharyngeal muscle (TP), the cricopharyngeal muscle (CP) and the cervical esophagus muscle (CE) of the cat, labeled neurons were identified in the nucleus retrofacialis and the rostral part of the nucleus ambiguus ipsilaterally. The rostral end of the labeled cell column was located more rostrally for CeP and HP than for TP, CP and CE. No difference was noted within the former two or within the latter three. The level of the caudal end of the labeled cell column became more caudal in the order of CeP, HP, TP and CP. The caudal end was located more rostral for CE than for TP. The neurons for CE were located more ventro-laterally than those for the other muscles.  相似文献   
63.
Pulmonary dysfunction is a significant complication following allogeneic hematopoietic stem cell transplantation (HSCT), and is associated with significant morbidity and mortality. Effective antimicrobial prophylaxis and treatment strategies have increased the incidence of noninfectious lung injury, which can occur in the early posttransplant period or in the months and years that follow. Late-onset noninfectious pulmonary complications are frequently encountered, but diagnostic criteria and terminology for these disorders can be confusing and therapeutic approaches are suboptimal. As a consequence, inaccurate diagnosis of these conditions may hamper the appropriate data collection, enrollment into clinical trials, and appropriate patient care. The purpose of this review is to clarify the pathogenesis and diagnostic criteria of representative conditions, such as bronchiolitis obliterans syndrome and bronchiolitis obliterans organizing pneumonia, and to discuss the appropriate diagnostic strategies and treatment options.  相似文献   
64.
The presence of lactose-fermenting Salmonella strains in clinical case materials presented to microbiology laboratories presents problems in detection and identification. Failure to detect these strains also presents a public health problem. The laboratory methods used in detecting lactose-fermenting Salmonella enterica serotype Typhimurium from six outbreaks of salmonellosis in veal calves are described. Each outbreak was caused by a multiply-resistant and lactose-fermenting strain of S. enterica serotype Typhimurium. The use of Levine eosin-methylene blue agar in combination with screening of suspect colonies for C8 esterase enzyme and inoculation of colonies into sulfide-indole-motility medium for hydrogen sulfide production was particularly effective for their detection. A hypothesis for the creation of lactose-fermenting salmonellae in the environment is presented. It is proposed that the environment and husbandry practices of veal-raising barns provide a unique niche in which lactose-fermenting salmonellae may arise.  相似文献   
65.
OBJECTIVE: Inhaled corticosteroids play a pivotal role in the treatment of asthma. To observe the mechanisms of glucocorticoids, we focused our study on the comparison of several glucocorticoids' effects on eotaxin expression in the airway epithelial cells. METHODS: Airway epithelial cell line BEAS-2B was cultured in vitro. Cells were preincubated with or without glucocorticoids (becromethasone dipropionate; BDP, budesonide; BUD, fluticasone propionate; FP) and stimulated with TNFalpha and/or IL-4. Protein levels of eotaxin in the supernatants of the cultured cells were determined by ELISA. RESULTS AND CONCLUSIONS: TNFalpha and IL-4 increased the levels of eotaxin in BEAS-2B cells. Combination of these cytokines synergistically upregulated the eotaxin expression as reported previously. Each glucocorticoid significantly inhibited the expression of eotaxin protein induced with TNFalpha and IL-4 and the compared efficacy was in order of FP>BUD>BDP. FP seemed most potent and the inhibitory effect was also observed with relatively low concentration such as 10 (-10)M. Taken together, the comparison of the potency of each glucocorticoid using airway epithelial cells may reflect the efficacy of these drugs in asthmatics.  相似文献   
66.
Phosphoglycerate kinase (PGK) is an enzyme that produces one ATP molecule in the glycolytic pathway. Clonorchis sinensis is largely dependent on glycolysis for energy production. We performed immunoelectron microscopy on adult C. sinensis by using mouse immune serum raised against recombinant C. sinensis PGK. A high density of gold particles was found in the microvilli of the intestinal epithelium and in lamellae of the sperm duct. PGK was common in the somatic cells of intra-uterine eggs and in excreted products. It was localized with moderate intensity in muscular fibers of the subtegumental muscle layer, and in the myoepithelia of the intestine and excretory bladder. We suggest that PGK plays an essential role in C. sinensis energy production for movement via muscle contraction.  相似文献   
67.
Otitis media with effusion (OME) is one of the most common ear diseases. Bacterial endotoxins and several inflammatory cytokines appear to be involved in the pathogenesis of OME in children; however, little is known of the immunological aspects of the onset of OME in adults. We sought to determine the presence of macrophage migration inhibitory factor (MIF) as well as interleukin 1beta (IL-1beta), tumor necrosis factor alpha (TNF-alpha), RANTES (regulated upon activation, normal T-cell expressed and presumably secreted), and endotoxin in middle ear effusions (MEEs) from adult patients with OME. In addition, the levels of MIF in MEEs from adults and children were compared. MEE was obtained from 95 adults and 11 children. The levels of MIF, IL-1beta, TNF-alpha, and RANTES were determined by enzyme-linked immunosorbent assay, and the concentrations of endotoxin and total protein were determined by the Endospec assay and bicinchoninic acid assay, respectively. MIF was detected in 97.9% of the MEEs from adults, while endotoxin, IL-1beta, TNF-alpha, and RANTES were detected in 96.8, 12.6, 5.3, and 43.9%, respectively. In addition, the level of MIF was significantly higher than those of endotoxin, IL-1beta, and TNF-alpha. A positive correlation between the levels of MIF and endotoxin was observed. MIF and endotoxin were detected in 81.8 and 72.7%, respectively, of the MEEs from the children. The level of MIF was significantly higher in the children, and conversely that of endotoxin was significantly higher in the adults. These results suggest that the interaction between MIF and endotoxin may promote fluid collection in the middle ear, particularly in adults.  相似文献   
68.
Following improvements in therapy for childhood malignancies, the striking increase in survival rate over the past 30 years has led to the increase risk of developing second malignant neoplasms (SMNs). We report a case of colorectal carcinoma as a SMN, following treatment for rhabdomyosarcoma. The patient was diagnosed with rhabdomyosarcoma of the urinary bladder at his age of three years, and developed adenocarcinoma in the colon 13 years later. Histologic examination of the surgical specimen revealed adenocarcinoma involving the rectosigmoid area with radiation colitis in its background. The tumor cells showed strong immunoreactivity for p53 protein, suggesting the role of irradiation and p53 mutation in carcinogenesis. This case emphasizes the need for dose observation in survivors of early childhood malignancies treated with radiation and multiagent chemotherapy.  相似文献   
69.
Adrenal chromaffin cells, obtained from a therapeutically aborted human fetus of about 11 weeks gestation, were cultured for 3 weeks in vitro and then transplanted to the striatum of rats. Transplanted cells became established through strands of tissue growing into the host striatum. No signs of inflammation or rejection were observed up to the time of sacrifice one month post-transplantation. Histofluorescence examination of the implanted areas showed many clusters of cells having an intensely positive catecholamine fluorescence with some of the cells developing conspicuous processes. This study, showing survival of cultured human adrenal chromaffin cells transplanted into rat brain tissue, might indicate the feasibility of using cultured human material for future human neuronal transplantation studies as a therapeutic measure.  相似文献   
70.
To study the neuronal mechanism of a conditioned taste-aversion (CTA) learning in the pond snail Lymnaea stagnalis, we examined the synaptic connection between the neuron 1 medial (N1M) cell and the cerebral giant cell (CGC), the former is an interneuron in central pattern generator for the feeding response and the latter is a regulatory neuron to the central pattern generator. Inhibitory postsynaptic potential (IPSP) which was evoked in the N1M cell by activation of the CGC was larger and lasted longer in the conditioned animal than that in the control animal. The electrical properties of the cell body of CGC and the responses of the CGC to the chemosensory inputs were not changed during the CTA learning. These results, together with the previous report indicating the existence of excitatory projection from the N1M cell to the feeding motoneuron, suggest that enhanced IPSP in the N1M cell may underlie the suppression of feeding responses in the Lymnaea CTA learning.  相似文献   
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