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91.
To examine early intercellular junction changes caused by treatmentwith 9, 10-dimethyl-l, 2-benzanthracene (DMBA), rat lingualepithelium was cultivated in isolation and observed by electrophysiological,freeze-fracture and whole-mount electron microscopy. Electrophysiologicalmeasurements showed a transient decrease in membrane potentialof -10.2 mV 6 h after the treatment. It returned to almost thesame level as that of the control group 1 day later. Six hoursafter treatment, input resistance decreased rapidly to 5.3 Mbut increased to 18.0 M 12 h after treatment. Transient reductionof input resistance and membrane potential occurred prior tothe decrease in the coupling ratio 6 h after treatment withDMBA. In freeze-fracture replicas, the number of gap junctionsdecreased by 45% of the control value 6 h after treatment withDMBA. At 12 h and thereafter, the number and area of gap junctionssubsequently decreased by 60–80% of the control value.Alterations in the number and area of desmosomes were similarto those of the gap junctions. The formation of epithelial cytoskeletons,partially devoid of the 2–4 and 5–8 nm filamentswas also observed. A decrease in the density of filament networksbeneath the plasma membranes was especially apparent. Treatmentwith a carcinogen brought about morphological cellular changesas early as 6 h after treatment, and such early changes mighttrigger metabolic cellular abnormalities. Affected cells appearto move away from normal cells in a process of repeated destructionand revision of intercellular junctions, and cytoskeletons.  相似文献   
92.
The prebiotic effect of high β-glucan barley (HGB) flour on the innate immune system of high-fat model mice was investigated. C57BL/6J male mice were fed a high-fat diet supplemented with HGB flour for 90 days. Secretory immunoglobulin A (sIgA) in the cecum and serum were analyzed by enzyme-linked immunosorbent assays (ELISA). Real-time PCR was used to determine mRNA expression levels of pro- and anti-inflammatory cytokines such as interleukin (IL)-10 and IL-6 in the ileum as well as the composition of the microbiota in the cecum. Concentrations of short-chain fatty acids (SCFAs) and organic acids were analyzed by GC/MS. Concentrations of sIgA in the cecum and serum were increased in the HGB group compared to the control. Gene expression levels of IL-10 and polymeric immunoglobulin receptor (pIgR) significantly increased in the HGB group. HGB intake increased the bacterial count of microbiota, such as Bifidobacterium and Lactobacillus. Concentrations of propionate and lactate in the cecum were increased in the HGB group, and a positive correlation was found between these organic acids and the IL-10 expression level. Our findings showed that HGB flour enhanced immune function such as IgA secretion and IL-10 expression, even when the immune system was deteriorated by a high-fat diet. Moreover, we found that HGB flour modulated the gut microbiota, which increased the concentration of SCFAs, thereby stimulating the immune system.  相似文献   
93.
BackgroundPerforming total hip arthroplasty (THA) as early as possible is recommended for rapidly destructive coxarthrosis (RDC) as it causes pain that becomes progressively more severe. However, acetabular bone loss remains an issue in THA. Special devices, such as a Kerboull-type plate, may be used for acetabular bone defects, but the procedure is highly invasive and often the patients are elderly, further complicating matters. We retrospectively investigated the clinical and radiographic results of THA using conventional hydroxyapatite-coated cementless cup in RDC.MethodsA total of 32 patients (35 hips) with RDC were enrolled in the study with a minimum 10-year follow-up. All THAs were performed using conventional hydroxyapatite-coated cementless cup. All patients were evaluated clinically according to the Harris hip score (HHS). Acetabular bone deficiency was classified according to the American Academy of Orthopaedic Surgeons (AAOS) classification.ResultsEleven hips (31%) were AAOS type III, and none were type IV. Total HHS significantly improved from 36.5 to 79.4 (p < 0.01). Two cups exhibited loosening. The overall implant-associated survival rate after 10 years was 91.4%.ConclusionsClinical results of THA using conventional cementless implants for patients with RDC were acceptable. Thus, THA using conventional cementless implant is an effective and safe surgery for patients with RDC, minimizing surgical stress.  相似文献   
94.
Five cases of alveolar soft part sarcoma, 5 cases of granular cell tumor, and 6 cases of paraganglioma were investigated immunohistochemically to examine the expression of tissue-specific intermediate filaments (cytokeratin, vimentin, desmin, and glial fibrillary acidic protein (GFAP], actin, myoglobin, and nervous tissue markers (S-100 protein, neuron-specific enolase, and Leu-7). In alveolar soft part sarcomas, some of the tumor cells were positive for desmin, but negative for nervous tissue markers. The tumor cells of granular cell tumors were stained with anti-S-100 protein antibody, but not with anti-neuron-specific enolase antibody. In contrast, the tumor cells of paragangliomas were positive for neuron-specific enolase, but not for S-100 protein except for stellate cells surrounding the tumor cell nests. This immunohistochemical approach was valuable for the differential diagnosis of these three tumors. Furthermore, the complete absence of cytokeratin in all of the tumor cells may be helpful in distinguishing these three tumors from metastatic carcinoma in soft tissue. The histogenesis of alveolar soft part sarcoma is a matter of controversy. The result that besides desmin actin was also demonstrated in some of the tumor cells may support the myogenic origin of this tumor.  相似文献   
95.
We examined the effect of GM1-ganglioside in combination with cholera toxin B, and synthetic α-sialyl cholesterol (α-SC) on neutral amino acid (tritiated α-aminoisobutyric acid, [3H]AIB) uptake, protein synthesis ([3H]leucine incorporation), and Na+, K+-ATPase activity in isolated superior cervical ganglia (SCG) and nodose ganglia (NG) from adult rats after aerobic incubation, usually for 2 h at 37°C in vitro. Cholera toxin B, that specifically masks the oligosaccharide chain of GM1-ganglioside, antagonized the GM1-induced changes in [3H]AIB uptake, [3H]leucine incorporation, and Na+, K+-ATPase activity almost completely in SCG, but partially in NG. Although cholesterol itself had little effect on either [3H]AIB uptake and Na+, K+-ATPase activity both in SCG and NG, α-SC caused considerable reduction of both amino acid uptake and the transport enzyme activity in each ganglia. However, cholesterol was more effective than α-SC in decreasing [3H]leucine incorporation in either ganglia. Whereas addition of EGTA markedly reduced either GM1-induced or α-SC-induced change in [3H]leucine incorporation into acid-insoluble fraction in both SCG and NG, application of Ca2+ ionophore produced considerable recovery of the protein synthesis from the inhibited level by Ca2+-deprivation. ATP and creatine phosphate contents in SCG were elevated by the presence of GM1 or α-SC, whereas [3H]AIB uptake and Na+, K+-ATPase activity were inhibited, suggesting that utilization for membrane transport was diminished as a result of GM1- or α-SC-induced decrease of ATPase activity.  相似文献   
96.
97.
The present study was undertaken to investigate the effectsof transforming growth factor (TGF)-1 on ovarian steroidogenesisin immature or moderately mature porcine granulosa cells invitro. TGF-1 (0.01–10 ng/ml) significantly attenuatedprogesterone release from the basal and follicle stimulatinghormone-stimulated porcine granulosa cells, and significantlyincreased DNA synthesis. TGF-1 also significantly increasedthe extracellular accumulation of cyclic AMP, but did not changethe production of inositol phosphate or the intracellular calciumconcentration in these cells. Thus, TGF-1 appears to have adirect effect on porcine granulosa cell function, regulatingthe differential synthesis of progesterone mainly via the intracellularsignal transduction of the cyclic AMP—protein kinase Apathway. This growth factor may play a physiologically significantrole in controlling differentiation of immature and moderatelymature porcine granulosa cells via an autocrine/paracrine mechanism.  相似文献   
98.
Fan Z  Isobe K  Emi N  Nakashima I 《Oncology reports》1994,1(6):1113-1116
Tumor necrosis factor-alpha receptor cDNA (TNFR-1 or TNFR-2) was inserted into a retrovirus derived vector. Recombinant vector was transfected into packaging cell line. The transfectants producing high titer of virus containing TNFR-1 or TNFR-2 cDNA were obtained. Human stomach cancer cells that poorly expressed TNFR-1 or TNFR-2 were infected with this virus as an in vitro model experiment of gene therapy. The stomach cancer cells that were infected with recombinant virus expressed TNFR-1 or TNFR-2 and were effectively killed by recombinant TNF.  相似文献   
99.
The multiple tumor suppressor 1 (MTS1) gene is homozygously deleted frequently in cell lines derived from a wide variety of tumors. We investigated the deletion of the MTS1 gene in esophageal cancer cell lines and primary esophageal squamous carcinomas using the polymerase chain reaction. Sixteen and 15 of 23 esophageal cancer cell lines showed homozygous deletion of MTS1 exon 1 and exon 2, respectively, while none of 21 primary esophageal carcinomas showed the deletion. An analysis of MTS1 gene mutations was carried out by direct DNA sequencing in 8 cell lines and 21 primary carcinomas showing no homozygous deletion. In contrast to previous reports of esophageal carcinoma, there were no mutations recognized in the region sequenced. Our study suggests that the inactivation of the MTS 1 gene may play an important role in esophageal carcinoma cell lines but may be less important in primary carcinomas of the human esophagus.  相似文献   
100.
PURPOSE: To evaluate the cochlear modiolus with thin-section magnetic resonance (MR) imaging in healthy subjects and patients with a large endolymphatic duct and sac, and to assess whether the cochlea is normal or abnormal in patients with a large endolymphatic duct and sac. MATERIALS AND METHODS: MR images were obtained in 10 ears in five volunteers (group 1), 40 ears in 20 patients with bilateral sensory hearing loss (group 2), three ears in two patients with Mondini malformation (group 3), and 12 ears in seven patients with a large endolymphatic duct and sac (group 4). RESULTS: In groups 1 and 2, all modiolar areas were larger than 4.0 mm2. In group 3, each modiolus was smaller than 2.0 mm2. In group 4, modiolar areas were smaller than 2.0 mm2 in eight ears and were larger than 4.0 mm2 in four ears. CONCLUSION: Findings in this study confirm that a large endolymphatic duct and sac is frequently associated with modiolar deficiency, but the modiolar area is normal in some cases. This result does not support the recently proposed hypothesis that hearing loss with a large endolymphatic duct and sac is caused by the transmission of subarachnoid pressure forces into the labyrinth through a deficient modiolus.  相似文献   
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