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81.
Chondroitin sulfate dipalmitoylphosphatidylethanolamine (CS-PE), when immobilized onto substratum, inhibited the adhesion of B16F10 mouse melanoma cells to fibronectin-coated dishes (anti-adhesion activity). CS-PE showed the most potent anti-adhesion activity for the melanoma cells among various GAG-PEs. CS-PE also inhibited the adhesion of B16F10 cells to Matrigel and the invasion of the cells into Matrigel. In the in vivo system of experimental metastasis, administration of B16F10 cells with CS-PE into C57BL/6 mice significantly inhibited lung metastasis. The inhibition degree of CS or hyaluronic acid-PE was lower than CS-PE. CS-PE administered intravenously into mice before the injection of B16F10 cells also inhibited metastasis. Pretreatment of B16F10 cells with CS-PE caused some but a lower degree of inhibition. When CS-PE was injected intravenously into mice, more binding in the lung was found than when CS was injected. CS-PE but not CS inhibited the retention in the lung of fluorochrome-labeled B16F10 cells when injected intravenously into mice. Since there was no significant effect of CS-PE on the viability and growth of B16F10 cells, the results suggest that CS-PE immobilized onto the subendothelial matrix may prevent melanoma cells from adhering to the subendothelial substrata of lung capillaries and inhibit subsequent invasion processes of metastasis.  相似文献   
82.
A deficiency of citrin, which is encoded by the SLC25A13 gene, causes both adult-onset type II citrullinemia (CTLN2) and neonatal intrahepatic cholestasis (NICCD). We analyzed 16 patients with NICCD to clarify the clinical features of the disease. Severe intrahepatic cholestasis with fatty liver was the most common symptom, but the accompanying clinical features were variable, namely; suspected cases of neonatal hepatitis or biliary atresia, positive results from newborn screening, tyrosinemia, failure to thrive, hemolytic anemia, bleeding tendencies and ketotic hypoglycemia. Laboratory data showed elevated serum bile acid levels, hypoproteinemia, low levels of vitamin K-dependent coagulation factors, and hypergalactosemia. Hypercitrullinemia was detected in 11 out of 15 patients examined. Most of the patients were given a lactose-free and/or medium chain triglycerides-enriched formula and lipid-soluble vitamins. The prognosis of the 16 patients is going fairy well at present, but we should observe these patients carefully to see if they manifest any symptom of CTLN2 in the future.  相似文献   
83.
Fibronectin and C1q frequently co-precipitated in cryoglobulins from patients with SLE. As a portion of the C1q molecule is similar to collagen to which fibronectin has a high affinity, we studied whether fibronectin specifically bound to C1q. Fibronectin was found to bind to both native and heat-inactivated C1q. The binding was enhanced by Ca++ and low ionic strength. We have also demonstrated that fibronectin is capable of binding to C1q fixed to immune complexes. The interaction between fibronectin and C1q may play a role in cryoglobulin formation and in clearance of immune complexes by reticuloendothelial system.  相似文献   
84.
85.
Genomic subtractive hybridization was used to design Prevotella nigrescens-specific primers and TaqMan probes. Based on this technique, a TaqMan real-time PCR assay was developed for quantifying four oral black-pigmented Prevotella species. The combination of real-time PCR and genomic subtractive hybridization is useful for preparing species-specific primer-probe sets for closely related species.  相似文献   
86.
BACKGROUND. Antibodies to thyroid-stimulating hormone (TSH) receptors that stimulate the thyroid gland cause hyperthyroidism in patients with Graves' disease, and their production during antithyroid drug treatment is an important determinant of the course of the disease. One factor that might contribute to the persistent production of antibodies to TSH receptors is stimulation of the release of thyroid antigens by TSH during antithyroid drug therapy. We therefore studied the effect of the suppression of TSH secretion by thyroxine on the levels of antibodies to TSH receptors after thyroid hormone secretion had been normalized by methimazole. METHODS AND RESULTS. The levels of antibodies to TSH receptors were measured during treatment with methimazole, either alone or in combination with thyroxine, in 109 patients with hyperthyroidism due to Graves' disease. The patients first received 30 mg of methimazole daily for six months. All were euthyroid after six months, and their mean (+/- SD) level of antibodies to TSH receptors decreased from 64 +/- 9 percent to 25 +/- 15 percent (P less than 0.01; normal, 2.9 +/- 1.4 percent). Sixty patients then received 100 micrograms of thyroxine and 10 mg of methimazole and 49 received placebo and 10 mg of methimazole daily for one year. In the thyroxine-treated group, the mean serum thyroxine concentration increased from 108 +/- 16 nmol per liter to 145 +/- 11 nmol per liter (P less than 0.01), and the level of antibodies to TSH receptors decreased from 28 +/- 10 percent to 10 +/- 3 percent after one month of combination therapy. In the patients who received placebo and methimazole, the mean serum thyroxine concentration decreased and the level of antibodies to TSH receptors did not change. Methimazole, but not thyroxine or placebo, was discontinued in each group 1 1/2 years after the beginning of treatment. The level of antibodies to TSH receptors further decreased (from 6.6 +/- 3.2 percent at the time methimazole was discontinued to 2.1 +/- 1.2 percent one year later) in the patients who continued to receive thyroxine, but it increased (from 9.1 +/- 4.8 percent to 17.3 +/- 5.8 percent during the same period) in the patients who received placebo. One patient in the thyroxine-treated group (1.7 percent) and 17 patients in the placebo group (34.7 percent) had recurrences of hyperthyroidism within three years after the discontinuation of methimazole. CONCLUSIONS. The administration of thyroxine during antithyroid drug treatment decreases both the production of antibodies to TSH receptors and the frequency of recurrence of hyperthyroidism.  相似文献   
87.
The experimentally induced cryptorchid mouse model is useful for elucidating the in vivo molecular mechanism of germ cell apoptosis. Apoptosis, in general, is thought to be partly regulated by the ubiquitin-proteasome system. Here, we analyzed the function of two closely related members of the ubiquitin C-terminal hydrolase (UCH) family in testicular germ cell apoptosis experimentally induced by cryptorchidism. The two enzymes, UCH-L1 and UCH-L3, deubiquitinate ubiquitin-protein conjugates and control the cellular balance of ubiquitin. The testes of gracile axonal dystrophy (gad) mice, which lack UCH-L1, were resistant to cryptorchid stress-related injury and had reduced ubiquitin levels. The level of both anti-apoptotic (Bcl-2 family and XIAP) and prosurvival (pCREB and BDNF) proteins was significantly higher in gad mice after cryptorchid stress. In contrast, Uchl3 knockout mice showed profound testicular atrophy and apoptotic germ cell loss after cryptorchid injury. Ubiquitin level was not significantly different between wild-type and Uchl3 knockout mice, whereas the levels of Nedd8 and the apoptotic proteins p53, Bax, and caspase3 were elevated in Uchl3 knockout mice. These results demonstrate that UCH-L1 and UCH-L3 function differentially to regulate the cellular levels of anti-apoptotic, prosurvival, and apoptotic proteins during testicular germ cell apoptosis.  相似文献   
88.
BACKGROUND: Japanese cedar and cypress pollen share a common antigen. The cedar pollen season is followed by the cypress pollen season. However, both the clinical significance and involvement of cypress pollinosis in the treatment of the cedar pollinosis have not yet been clarified. METHODS: The clinical efficacy of sublingual immunotherapy with cedar pollen extract for cedar pollinosis was evaluated during the cypress pollen dispersal season in Japan. In addition, the change in cypress pollen specific IgE antibodies of the patients with cedar pollinosis was examined before and after the pollen season. RESULTS: Sublingual immunotherapy with cedar pollen extract did not improve the clinical symptoms of the cedar pollinosis patients combined with cypress pollinosis in the cypress pollen season. The cypress pollen specific IgE antibodies were found to demonstrate significant seasonal changes. CONCLUSION: The presence of cypress pollinosis should therefore be taken into consideration when planning the optimal treatment for cedar pollinosis. Sublingual immunotherapy with cedar pollen extract may not be effective for cypress pollinosis.  相似文献   
89.
The expression level of major histocompatibility class I (MHC-I) and the extent of down-regulation of MHC-I after an anti-MHC-I antibody treatment in numerous human T-cell leukemia virus type 1 (HTLV-1)-positive and -negative lymphocytic cell lines were examined. While there was no clear correlation between the expression level of MHC-I and the presence of HTLV-1 genome, a relatively low level of MHC-I down-regulation was generally induced in HTLV-1-positive cells by the antibody. The results may suggest the potential involvement of MHC-I in HTLV-1 leukemogenesis.  相似文献   
90.
Angiomyomatous hamartoma is a rare disease with a predisposition for the inguinal lymph nodes. A 51-year-old male patient visited a local hospital because of a right inguinal mass, measuring 3 x 4 cm in size, which was resected. The resected specimen showed irregularly distributed thick-walled vessels in the hilum, extending into the medulla and focally into the cortex of the node, eventually becoming more dispersed and associated with smooth muscle cells splaying into sclerotic stroma. These findings are compatible with an angiomyomatous hamartoma. Another tumor-like mass appeared shortly after the resection at the same location, but was not an angiomyomatous hamartoma, rather it was composed of edematous stromal tissue with proliferating smooth muscle cells. The stromal component included thick-walled blood vessels and lymphatics. Although it could not be determined whether these associated changes in the surrounding stroma are a cause or an effect of angiomyomatous hamartoma, they indicate the clinical difficulty in determining an appropriate area of resection and may provide clues to the pathogenesis of angiomyomatous hamartoma.  相似文献   
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