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61.
A Japanese patient with tuberous sclerosis (TSC), who manifested with multiple lung cysts and pneumothorax, is described. All exons of two TSC genes, TSC1 and TSC2, in peripheral blood leukocytes from the patient were analyzed by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP). A novel T-to-G transition was found in exon 19 of TSC2 at nucleotide position 2168. This mutation caused an amino acid change, L717R. There was no such mutation in any other family members or in 100 normal Japanese. An automated sequencer-assisted quantitative analysis of normal and mutated SSCP-bands revealed no loss of heterozygosity (LOH) in the lung cyst tissue of the patient.  相似文献   
62.
F213I突变型高雪氏病分子伴侣治疗方法的研究   总被引:3,自引:0,他引:3  
目的 研究高雪氏病新的分子治疗方法。方法 用β-葡萄糖脑昔脂酶(β-glucocerebrosidase,β-Glc)(EC3.2.1.45)的底物类似物(glucocerebroside analogue,GCA)作为分子伴侣,处理体外培养的不同突变型的高雪氏病患者皮肤成纤维细胞,采用荧光酶学手段测定β-Glc活性;Western印迹杂交技术分析该酶蛋白表达的量;细胞双染确定β-Glc在细胞内的定位;薄层层析法分析葡萄糖脑苷脂的降解情况。结果 该酶的底物类似物GCA可以提高体外培养的F213I突变型患者成纤维细胞内β-Glc活性;增加该酶蛋白的表达量;促进该酶蛋白向溶酶体内转运,加速底物葡萄糖脑苷脂(glucocerebroside,GlcCer)的降解。结论低分子量的GCA作为一种分子伴侣可能为F213I突变型高雪氏病的治疗开辟一条新的途径。  相似文献   
63.
Summary We report here the nucleotide sequences of the core region of HCV isolates from Egyptian and Yemeni patients and the method for classifying these HCV isolates by phylogenetic analysis. Sequence comparison suggested that the genotypes of these isolates were the same. Preliminary phylogenetic analysis of the HCV core region indicated that the genotypes of both isolates were 1c. However, an additional phylogenetic tree of the HCV core region constructed using a greater number of HCV isolates than that used in the preliminary analysis and on the basis of alignment of nucleotide sequences in an appropriate length indicated that the genotypes of these isolates were 4 and not 1c. For a more detailed analysis, the nucleotide sequences of the HCV E1 region as well as the core region for the same Yemeni patient were determined. A phylogenetic tree of the E1 region confirmed that the genotype of the HCV isolate from the Yemeni patient was 4. These data indicate that even when classifying HCV isolates using phylogenetic analysis, the misclassification would occur if care is not taken regarding the number and sequence lengths of the isolates included in the analysis.  相似文献   
64.
The ocular inflammation and antibody production that follow intravitreal injection of rabbit eyes with bovine gamma globulin were suppressed by treatment with Cytoxan by the intramuscular (i.m.) route. The drug suppressed PFC responses of uveal tract and corneal cells when it was administered, beginning as late as 5 days after immunization, if treatment was continued until day 12 or 13. Short-term treatments and treatment with smaller Cytoxan doses were less effective. We noted a good correlation between the presence or absence of ocular inflammation, suppression of ocular PFC responses and depression of serum, aqueous humour and vitreous humour antibody titres. In some treatment groups ocular antibody production seemed to be completely suppressed, while in others antibody production was significantly delayed.  相似文献   
65.
Plasma lipopolysaccharide (LPS)-binding protein (LBP) and membrane CD14 function to enhance the responses of monocytes to low concentrations of endotoxin. Surprisingly, recent reports have suggested that LBP or CD14 may be dispensable for macrophage responses to low concentrations of LPS or may even exert an inhibitory effect in the case of LBP. We therefore investigated whether LBP and CD14 participated in the response of mouse peritoneal exudate macrophages (PEM) to LPS stimulation. In the presence of a low amount of plasma (<1%) or of recombinant mouse or human LBP, PEM were found to respond to low concentrations of LPS (<5 to 10 ng/ml) in an LBP- and CD14-dependent manner. However, tumor necrosis factor production (not interleukin-6 production) by LPS-stimulated PEM was reduced when cells were stimulated in the presence of higher concentrations of plasma or serum (5 or 10%). Yet, the inhibitory effect of plasma or serum was not mediated by LBP. Taken together with previous results obtained with LBP and CD14 knockout mice in models of experimental endotoxemia, the present data confirm a critical part for LBP and CD14 in innate immune responses of both blood monocytes and tissue macrophages to endotoxins.  相似文献   
66.
Summary Studies of the influences of physical exercise of short duration (bicycle ergometer, 200 W for 30 min) on the activities of carbonic anhydrase isoenzymes (CA-B and CA-C types) and zinc concentration in erythrocytes were made on 5 untrained healthy male volunteers. The subjects were rested for 30 min after the exercise. There were significant decreases in the levels of zinc, CA-B, total carbonic anhydrase activity and CA-B-dependent activity immediately after exercise, but after 30 min of rest they all returned to their pre-exercise levels. No significant change in CA-C level or CA-C-dependent activity was found after exercise. Immediately after exercise, total carbonic anhydrase activity and CA-B-dependent activity following the addition of Zn2+ showed significant increases, compared with their respective activities without Zn2+ addition. However, no such effects were observed just before exercise or after rest; the addition of Zn2+ had no effect on CA-C-dependent activity at any time. A significant correlation was found between the changes in concentration of zinc and CA-B-dependent activity after exercise (r=0.711). The findings of the present study suggest that active CA-B enzymes are converted in part to inactive enzymes during acute physical exercise, possibly by decreased zinc binding. Moreover, the change in CA-B-dependent activity correlated well with the changes in pH and HCO3 concentrations in venous blood (r=0.853 and r=0.718, respectively). One may speculate that an adaptive decrease in CA-B-dependent activity in erythrocytes occurs with increased acidification in blood during heavy physical exercise of short duration.The present study was presented to the Fifth International Symposium on the Biochemistry of Exercise, Boston, June 1–5, 1982  相似文献   
67.
This is a case report of a malignant mesenchymoma of the esophagus in a 50?year-old Japanese man. The tumor was a sessile polypoid mass showing a downward invasion limited to the submucosa of the esophagus. Histologically, the lesion contained rhabdomyosarcomatous and osteosarcomatous areas, in addition to an ill-defined fibrosarcomatous element. In contrast with reports of carcinosarcoma up to the present, this tumor lacked any invasive lesion of an epithelial malignancy. The morphogenesis of these tumor groups was discussed from a hamartoblastomatous standpoint. Acta pathol. jpn. 34: 925~933, 1984.  相似文献   
68.
69.
Although rhythmic jaw movement in feeding has been studied in mammals, such as rats, rabbits and monkeys, the cellular and molecular mechanisms underlying it are not well understood. Transgenic and gene-targeting technologies enable direct control of the genetic makeup of the mouse, and have led to the development of a new category of reagents that have the potential to elucidate the cellular and molecular mechanisms of neural networks. The present study attempts to characterize rhythmic jaw movements in the mouse and to demonstrate its relevance to rhythmic jaw movements found in higher mammals using newly developed jaw-tracking systems and electromyograms of the masticatory muscles. The masticatory sequence of the mouse during feeding was classified into two stages, incision and chewing. Small and rapid (8 Hz) open-close jaw movements were observed during incision, while large and slow (5 Hz) open-close jaw movements were observed during chewing. Integrated electromyograms of the masseteric and digastric muscles were larger during chewing than those observed during incision. Licking behavior was associated with regular (8 Hz), small open-close jaw movements with smaller masseteric activity than those observed during mastication. Grooming showed variable patterns of jaw movement and electromyograms depending on the grooming site. These results suggest that there are neuronal mechanisms producing different frequencies of rhythmic jaw movements in the mouse, and we conclude that the mouse is useful for understanding rhythmic jaw movements in higher mammals.  相似文献   
70.
PROBLEM: The presence of antisperm antibodies (ASA) in males can reduce fecundity, however, relationship between the two is disputed. This study was performed to investigate if there is diversity of ASA bound to sperm surface using immunobead test (IBT) combined with complement dependent sperm immobilization test (SIT). METHODS: The ASA bound to sperm surface were detected using the direct IBT (D-IBT) in 275 semen samples. In some cases with ASA detected by D-IBT, sperm immobilizing antibodies bound to sperm surface were also evaluated using direct SIT (D-SIT). RESULTS: The incidence of the immunoglobulin G (IgG), IgA, and IgM classes of ASA detected by D-IBT were 2.5, 1.8, and 0.4%, respectively. Totally, nine (3.3%) infertile men had ASA on the sperm surface. D-SIT was tested positive in four (66.7%) of six cases with ASA assessed by D-IBT. CONCLUSIONS: Some of the sperm-bound antibodies are associated with complement dependent sperm immobilizing antibodies, indicating that there exists a heterogeneity of sperm-bound antibodies. This result might be one of the reasons for the controversy about the relationship between ASA and immunological infertility in men.  相似文献   
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