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51.
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   
52.
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   
53.
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   
54.
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   
55.
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   
56.
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   
57.
M Betz  G M H?nsch  M L Shin 《Immunobiology》1984,166(4-5):397-402
Incubation of Ehrlich ascites cells with normal or C1q or C2 deficient human sera results in killing of the cells. Killing occurred also in the absence of free Ca++, which supported by the fact that factor B and C3 were cleaved, leads to the conclusion that the alternative pathway of the complement system is activated on the surface of the Ehrlich ascites cells.  相似文献   
58.
In general, the etiologic factors of chronic paranasal sinusitis are systemic conditions such as nutrition, predisposition, allergy, and local factors such as nasal anatomic conditions. Among these factors, the development of unilateral sinusitis is a model case verifying the influence of local factors. In my study of 640 cases over a certain period of time, a comparison was made between 161 cases of unilateral sinusitis and 479 cases of bilateral sinusitis in order to verify the effects of local factors in the development of this disease. Patients with a history of previous sinus surgery or tumors were eliminated from the cases. 1. The male-female incidence rate, and the age distribution of the patients at the initial visit showed no prominent differences between unilateral and bilateral cases. 2. It was found that a larger number of cases of unilateral sinusitis had a duration of less than one year as compared to bilateral sinusitis which were longer than and year. Therefore it can be said that the duration of unilateral sinusitis is usually shorter than that of bilateral sinusitis. 3. In unilateral cases the patients with moderate to severe nasal septal deviation, one number of patients with septal deviation towards the diseased side was twice as high as that on the non-affected side. 4. The incidence rate of polyps occurring in the middle meatus was shown to be about twice as high in bilateral cases as in unilateral cases.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
59.
To isolate novel genes regulating neural induction, we used a DNA microarray approach. As neural induction is thought to occur by means of the inhibition of bone morphogenetic protein (BMP) signaling, BMP signaling was inhibited in ectodermal cells by overexpression of a dominant-negative receptor. RNAs were isolated from control animal cap explants and from dominant-negative BMP receptor expressing animal caps and subjected to a microarray experiment using newly generated high-density Xenopus DNA microarray chips representing over 17,000 unigenes. We have identified 77 genes that are induced in animal caps after inhibition of BMP signaling, and all of these genes were subjected to whole-mount in situ hybridization analysis. Thirty-two genes showed specific expression in neural tissues. Of the 32, 14 genes have never been linked to neural induction. Two genes that are highly induced by BMP inhibition are inhibitors of Wnt signaling, suggesting that a key step in neural induction is to produce Wnt antagonists to promote anterior neural plate development. Our current analysis also proves that a microarray approach is useful in identifying novel candidate factors involved in neural induction and patterning.  相似文献   
60.
This study employed two water-soluble and nontoxic molecules, sucrose and glycerol, to enhance the permeability of PEG-PHEMA polymer gels coated onto 100 kDa molecular weight cutoff polyethersulfone (PES) microdialysis probes. Sucrose precoating of the probes prior to prepolymer coating prevented penetration of the prepolymer into the microdialysis membrane. Glycerol mixed with the prepolymer introduced porosity in the polymer coating upon curing. The sucrose and glycerol were completely removed by soaking in PBS after curing of the polymer coat on the probe tip. Polymer coated probe glucose permeability was tested by measuring glucose recovery from PBS solutions. Biocompatibility was assessed by measuring glucose recovery of polymer coated probes from heparanized whole porcine blood. Results show that the sucrose and glycerol treatments yielded polymer coated probes with glucose permeability nearly equal to bare probes when tested in PBS solution, but that this increased permeability was not observed when tested in whole blood. This suggests that the thickness of the polymer films (10-100 microm), while not a limiting factor in PBS solution, may have presented a diffusion barrier to glucose recovered from blood. Surprisingly, however, the polymer coated probes exhibited less thrombus formation that did the bare probes after blood exposure.  相似文献   
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