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11.
Close linkage of MEN2A with RBP3 locus in Japanese kindreds   总被引:7,自引:0,他引:7  
Summary The gene responsible for multiple endocrine neoplasia type 2A (MEN2A) has recently been assigned to the pericentromeric region of chromsome 10 in European Caucasian kindreds by linkage analysis using a DNA marker, interstitial retinol-binding protein 3 (RBP3). We have found tight linkage between the MEN2A and RBP3 loci in Japanese MEN2A kindreds. The maximum lod score is 5.19 at a recombination fraction of 0.00. This result suggests that mutation of a certain gene close to RBP3 is responsible for MEN2A irrespective of ethnic backgrounds.  相似文献   
12.
Sixty-one Borrelia burgdorferi sensu lato strains from various sources (ticks, human, and wild animals) in Japan and two strains from ticks in Far Eastern Russia were classified on the basis of reactivity with 16 monoclonal antibodies (mAb) to outer surface protein A (OspA) and by DNA-DNA hybridization assay. Eleven OspA serotypes (J1 to J11) were recognized among the Japanese and the Far East Russian isolates (serotypes J1 to J9 were identified as B. garinii, serotype J10 was identified as B. afzelii, and serotype J11 corresponded to B. japonica), whereas 7 OspA serotypes for North American and European isolates previously reported (Bettina Wilske et al, J. Clin. Microbiol. 31:340-350, 1993) were not observed except for OspA serotype 2 which showed identical reactivity with OspA serotype J10. This finding provides helpful information for understanding the geographical distribution of Lyme disease borrelia and the development of vaccine and diagnostic tests. In conclusion: 1. B. burgdorferi sensu stricto has not been observed in Japan, 2. Japanese B. afzelii isolates are closely related to those from Europe, 3. B. garinii isolates from Japan are highly heterogeneous and apparently different from European B. garinii isolates.  相似文献   
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In a study of nine families with “site-specific” ovarian cancer (criterion: three or more cases of epithelial ovarian cancer and no cases of breast cancer diagnosed at age <50 years) we have obtained evidence of linkage to the breast-ovarian cancer susceptibility gene, BRCA1 on 17q12-21. If the risk of cancer in these families is assumed to be restricted to the ovary, the best estimate of the proportion of families linked to BRCA1 is .78 (95% confidence interval .32–1.0). If predisposition to both breast and ovarian cancer is assumed, the proportion linked is 1.0 (95% confidence interval .46–1.0). The linkage of familial site-specific ovarian cancer to BRCA1 indicates the possibility of predictive testing in such families; however, this is only appropriate in families where the evidence for linkage to BRCA1 is conclusive.  相似文献   
15.
Vacuolar membranes isolated from several species including fernand moss exhibited pyro-phosphate-dependent H+ transport activity.On immunoblot analysis, H+ -pyrophosphatase was detected inthe vacuolar membranes. A membrane integral protein of 23,000daltons was not found in the membranes of Chara, Conocephalum,or Kalanchoë. Thus, H+-pyrophosphatase may be a universalenzyme among green plants, but the 23-kDa protein is not a commonprotein of central vacuoles. (Received September 10, 1993; Accepted November 29, 1993)  相似文献   
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A synthetic 22-mer oligodeoxyribonucleotide having an AACGTT palindrome, AAC-22, induced interferon (IFN) production and augmented the natural killer (NK) activity in murine splenocytes, whereas its analogue, ACC-22, having an ACCGGT palindrome, did not. The binding of AAC-22 to splenocytes was not different from that of ACC-22. Lipofection of AAC-22 to splenocytes remarkably enhanced IFN production and NK cell activity, whereas that of ACC-22 caused little enhancement. These results strongly suggest that the prerequisite for IFN production is not the binding of AAC-22 to the cell surface receptors, but its penetration into the spleen cells.  相似文献   
18.
A specific-locus test was carried out to examine the mutagenic activity of N-ethyl-N-nitrosourea (ENU) on mouse primordial germ cells (PGC). Embryos of C3H/He mice were treated transplacentally with 30 or 50 mg ENU per kg of maternal body weight on day 8.5, 10.5, or 13.5 of gestation (G8.5 day, G10.5 day, or G13.5 day). Male and female mice that had been treated with ENU in embryonic stages were mated with female or male tester PW mice to detect recessive mutations induced in PGC.

ENU induced recessive mutations at a relatively high rate in PGC at these developmental stages. The most sensitive stage was G10.5 day. On G8.5 day, the induced mutation rate in males and females was not significantly different. Cluster mutations, which originate from the limited number of PGC and cell killing, were more frequently induced at an earlier developmental stage. The induced mutation rate per unit dose of ENU (1 mg/kg) was higher in G8.5 and G10.5 day PGC than in stem-cell spermatogonia. It can be concluded that mouse PGC are more sensitive than stem-cell spermatogonia to the induction of recessive mutations by ENU.  相似文献   

19.
Summary A human anaplastic thyroid cancer cell line K-119, derived from a 77-yr-old woman who had developed marked neutrophilia and underwent surgery for anaplastic thyroid cancer, has been established. The spindlelike and polygonal cells in shape are stably proliferating since the beginning of its culture 2 yr ago. The cells grow rapidly and the population doubling time is 26 h. The chromosomes show many abnormalities and many marker chromosomes have been observed. Heterotransplantation of the cells into nude mice has resulted in the formation of tumors that are histologically interpreted as anaplastic cancer. The most noteworthy characteristics of the cell line are the many Ki-67-positive cells (86.3%) and that the cell line spontaneously secretes granulocyte colony-stimulating factor (G-CSF) and releases increased amounts of G-CSF in response to the stimulation of tumor necrosis factor, interleukin 1α, and interleukin 1β. The conditioned medium obtained from K-119 cells contains an autocrine factor stimulating the proliferation of themselves.  相似文献   
20.
We have previously reported that the antitumor effect of OK-432, a streptococcal preparation, is markedly augmented when injected intratumorally together with fibrinogen (OK-432/fbg) [1]. In order to elucidate the effects of this immunotherapy on regional lymph nodes (RLN), we carried out both morphological and functional analyses of the RLN from colonic cancer patients treated with OK-432/ fbg. Computer-aided morphometry revealed that the maximal cross-sectional areas and the broadest diameters of the RLN were significantly greater (p<0.01) in patients who had undergone local immunotherapy than in patients who had not. The component structures of RLN, such as sinus, follicle and paracortex, were all enlarged in the OK-432/fbg-treated patients, and necrosis of metastatic tumors was observed. RLN lymphocytes recovered from OK-432/fbg treated patients showed elevated reactivity to phytohemagglutinin (PHA) and the stimulation index was clearly higher than that of control patients. Flow cytometric analysis revealed a predominance of T-cells, especially CD4 subsets, and higher positivity for both CD25 and HLA-DR. Furthermore, RLN lymphocytes killed more effectively K562 and Daudi cells in the patients who had had immunotherapy. These results suggest that the effect of local immunotherapy with OK-432/fbg is not restricted to the site of injection but extends to the lymph nodes, and contributes to tumor regression through the augmentation of cellular immunity.Abbreviations RLN regional lymph node(s) - OK-432/fbg OK-432/fibrinogen solution - PHA phytohemagglutinin - NK natural killer - LAK lymphocyte activated killer  相似文献   
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