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81.
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   
82.
Gangliosides, a family of glycosphingolipids that contain sialic acid, are abundant on the neuronal cell membranes, but their precise functions in the central nervous system remain largely undefined. In a previous study of GalNAc-T(-/-) mice engineered to lack beta1,4-N-acetylgalactos-aminyltransferase (GM2/GD2 synthase) to abolish any, complex gangliosides, we observed the reduction of nerve conduction velocity but did not find any obvious morphological change in the brain. In the present study, we observed morphological changes in the nerve fiber tracts of the spinal cord in these mice. In GalNAc-T(-/-) mice, the number of degenerated axons was markedly increased in the dorsal funiculus, tract of Lissauer, and dorsolateral funiculus of the cervical segment of the spinal cord as well as the dorsal funiculus and tract of Lissauer of the lumbar segment of the spinal cord. There were also increased numbers of unmyelinated fibers in GalNAc-T(-/-) mice. Loosened myelin sheaths and myelin sheaths separated from axons by wide spaces were also observed in GalNAc-T(-/-) mice. These results provide a morphological basis for the previously observed reduction in the nerve conduction velocity and suggest that complex gangliosides are essential for the maintenance of myelin and the integrity of nerve fibers of the spinal cord.  相似文献   
83.
We report a malformed female infant withde novo interstitial deletion of 4q[46,XX,del(4)(q27q28.2)]. The MN blood type analysis of the family members showed that the patient had an intact blood group-MN locus. The locus of the gene responsible for the MN antigen activity is confined to a 4q28.2–4q31.1 segment on the basis of the result of this patient and the previous mapping data.  相似文献   
84.
To evaluate the therapeutic potential of FX0685, a new triazole antifungal agent, for the treatment of opportunistic fungal infections, particularly systemic candidiasis and aspergillosis, in vitro and in vivo studies were performed using fluconazole (FLC), itraconazole (ITC) and/or amphotericin B (AMB) as reference drugs. A preliminary in vitro study showed that the antifungal activity of FX0685 against FLC-susceptible Candida albicans, several non-C. albicans Candida species and Cryptococcus neoformans was superior to that of FLC and comparable or superior to those of ITC and AMB, while the anti-Aspergillus fumigatus activity of FX0685 was to varying degrees lower than that of ITC. FX0685 appeared to be comparable to FLC and ITC in the treatment of murine systemic C. albicans and pulmonary A. fumigatus infection, respectively. The biological property of FX0685 was characterized by its potent in vitro and in vivo activity against FLC-resistant C. albicans. Part of this unique property was explained by the finding that it retained potent inhibitory activity against those CYP51 molecules in which amino acid substitutions confer a phenotype of resistance to FLC and some other azole derivatives. All of these results lead to the possibility that FX0685 may be a potential antifungal drug candidate for the treatment of various clinical forms of systemic candidiasis, including those caused by FLC-resistant C. albicans, as well as for the treatment of pulmonary aspergillosis.  相似文献   
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87.
CA19-9 widely used as a tumor marker of the pancreas and a bile duct. There are a number of reports which describes the measured value discrepancies between RIA and non-RIA kits. RIA results also have shown lack of the linearity over 70 U/ml when the samples are diluted. The pH condition at assay reaction for RIA had been suggested as the major reason, it has been denied by the results from the same pH condition at assay reaction used by COBAS CORE CA19-9 EIA II. On the other hand, the lack of RIA antibody titer is indicated for the discordant results by changing the sample volume to reagent volume ratio in the reaction. Our further investigation also indicates that the specific Lewis blood type, i.e. Le (a-b+), shows the linearity issues by RIA. The discrepancies are not caused by the reaction pH, but the amount of the antibody used in the RIA kit is closely associated. Considering the CA19-9 antibody nature used in RIA kit, which covers broad molecular range, users need to pay more attention to setting up each laboratory's measuring range.  相似文献   
88.
Heparin-induced thrombocytopenia(HIT) due to immunological mechanisms is known as an important adverse reaction to heparin treatment, and heparin treatment should be applied while keeping in mind the risk of onset of HIT 5-14 days after the initiation of heparin. The presence of HIT had not been fully recognized in clinical practice in Japan despite the management of HIT being well confirmed in Western countries. Recognition of HIT has increased since argatroban, a direct thrombin inhibitor, obtained the approval of the FDA for prevention and treatment of HIT. Although the incidence of HIT in Japan has not yet been clarified, there is some evidence that HIT is encountered in critically ill patients undergoing heparin anticoagulation. Clinical diagnosis of HIT is performed by means of thrombocytopenia of a drop of 50% or 100 x 10(30/microl for 5 -14 days after starting heparin treatment. Confirmatory laboratory tests examine whether the patients have antibodies against heparin/PF4 complexes or not. Two assay tests for detecting heparin/PF4 complex antibodies are available in Japan. As a functional test, the heparin-induced platelet aggregation method is easily performed and the result is obtained in a short time. The result of the test has, however, been misleading due to the selection of donors. Low platelet activity of the donors on the addition of heparin induces a negative response in spite of positive antibodies in the sample. Before testing samples, it is important to check heparin reactivity of the donor's platelets. Enzyme immunoassay detecting the antibodies is available as a commercial kit. Sensitivity obtained by enzyme immunoassay is very high and often introduces false-positives. Careful attention to interpretation of the result is required. Treatment of HIT should be started at the time of recognition of thrombocytopenia while antibody testing for HIT is performed. As an alternative anticoagulant to heparin, argatroban should immediately be applied to avoid complication of thrombosis. Thrombocytopenia and hypercoagulability quickly recover to the preheparin level by the appropriate use of argatroban.  相似文献   
89.
Citrin is a mitochondrial aspartate glutamate carrier primarily expressed in the liver, heart, and kidney. We found that adult-onset type II citrullinemia is caused by mutations in the SLC25A13 gene that encodes for citrin. In this report, we describe the frequency of SLC25A13 mutations, the roles of citrin as a member of the urea cycle and as a member of the malate-aspartate shuttle, the relationship between its functions and symptoms of citrin deficiency, and therapeutic issues.  相似文献   
90.
Summary We have examined the nonparallel changes in tampanic membrane temperatures (T ty) from the two ears in response to various changes in body and head positions. Upon assuming a lateral recumbent position, the T ty on the lower side increased while that on the upper side decreased. Pressure application over a wide area of the lateral chest only caused inconsistent and obscure asymmetric changes in T ty. A lateral flexion of the head with the subject sitting upright and a rotation of the head to the side in a supine position induced an increase in the T ty on the lower side compared to that on the upper side. The temperature and blood flow of the forehead often decreased on the lower side and increased on the upper side, although such responses were not always concomitant with the asymmetric changes in T ty. A dorsal flexion of the head with the subject in a reclining position caused a slight increase in the T ty, whereas raising the head upright induced a slight decrease in them. Two additional experiments were carried out with single photon emission computed tomography using 99mTc-hexamethylpropyleneamine oxime as tracer, and a slight, relative decrease in counts was noted in the right hemisphere during rotation of the head to the right. These results would strongly suggest that unilateral increases and decreases in T ty could have been caused by one-sided decreases and increases, respectively, in blood flow to the brain and/or the tympanic membrane, induced by a vasomotor reflex involving vestibular stimulation.  相似文献   
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