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1.
We have shown that administration of estrogen which increases prolactin (PRL) synthesis in the rat may be mediated by an increase in poly [adenosine diphosphate ribose (ADP-ribose)] synthesis. Present investigation was attempted to study whether poly (ADP-ribose) synthesis is involved in rat PRL gene expression during early pregnancy. Anterior pituitaries were obtained on days 0, 2, 4, 6, 8, 10 and 12 of pregnancy (group C). Another group of pregnant rats was given nicotinamide, an inhibitor of poly (ADP-ribose) synthesis twice a day intra-peritoneally from day 0 to the day of sacrifice (group N). Serum estradiol (E2) concentration was determined by radioimmunoassay. PRL mRNA was measured by cytoplasmic dot hybridization using 32P-labeled cDNA. Poly (ADP-ribose) synthesis was assessed by incubating purified nuclei with 14C-nicotinamide adenine dinucleotide. The serum concentration of E2 increased between days 2 and 4, and on day 6 it decreased to the level of day 0. It remained low until day 12. No difference in the serum E2 level was observed in groups C and N. In group C, PRL mRNA increased from day 2 and remained high until day 8. In group C, poly (ADP-ribose) synthesis increased between days 2 and 4, decreased on day 6 to the level of day 0, and thereafter gradually increased until day 10. Administration of nicotinamide abolished the increase in poly (ADP-ribose) synthesis observed in group C during early pregnancy. In group N, the increase in PRL mRNA was completely suppressed. It is suggested that the increase in PRL mRNA in early pregnancy may be mediated by increased poly (ADP-ribose) synthesis.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
2.
Taq I-generated HLA-DQrestriction fragment length polymorphism was examined in Japanese patients with narcolepsy. All patients were DR2 positive and shared a 6.0 kb fragment, although this fragment was found only in 54 % of the healthy DR2-positive Japanese. This finding added the DQ gene to the list of candidates for the possible narcolepsy-susceptibility gene. In contrast, there was no complete association between narcolepsy and DXrestriction fragment length polymorphism. These findings suggest that a narcolepsy-susceptibility gene is located closer to the DQ locus than to the DX locus.  相似文献   
3.
The previous study from this laboratory demonstrated that the corneal epithelium of 19-d-old chick embryo synthesizes two classes of sulfated glycoconjugates consisting of sulfated glycoproteins and proteoglycans (Yonekura, H., Oguri, K., Nakazawa, K., Shimizu, S., Nakanishi, Y., & Okayama, M. (1982) J. Biol. Chem. 257, 11166-11175). The present study demonstrated that when the sulfated glycoproteins labeled metabolically with [35S]sulfate and [3H]glucosamine were analyzed by SDS-PAGE, the 70,000 component (accounting for approximately 30% of the 35S and 35% of the 3H of the total sulfated glycoprotein) co-migrated with five major proteins with apparent molecular weights (Mrs) of 70,000, 66,000, 58,000, 51,000, and 48,000, which together accounted for about 57% of the total tissue protein. All five proteins cross-reacted with an antibody against human sole keratin, indicating that they are cytokeratin polypeptides of the corneal epithelium. Amino acid analysis demonstrated that they had high contents of glycine, serine, glutamic acid, leucine, and aspartic acid. Two-dimensional tryptic peptide maps indicated that they were all different. Analysis of radiolabeled materials released by alkaline borohydride treatment of the sulfated glycoproteins which were synthesized in the presence and absence of tunicamycin and co-purified with the five cytokeratin polypeptides, revealed that they contained both N- and O-glycosidically linked sulfated oligosaccharides. All the results obtained in the present study indicate that the five sulfated glycoproteins are similar, if not identical, to the cytokeratin polypeptides. This is consistent with the result in the accompanying paper that these sulfated glycoproteins are localized intracellularly.  相似文献   
4.
Summary Specific antisera to -melanotropin (-MSH) and corticotropin (ACTH 1-39) were used to obtain immunocytochemical evidence for the differential localization of -MSH and ACTH in the secretory granules of corticotropes of rat anterior pituitary. The specificity of the antisera was established by binding 131I-labeled -MSH and ACTH 1-39 to their respective antisera. Double-labeling immunocytochemistry (for -MSH, ferritin; for ACTH, colloidal gold) was performed. Some secretory granules were labeled with ferritin particles (-MSH), whereas others contained gold particles (ACTH). Only a few granules showed both ACTH and -MSH. In typical corticotropes (stellate in form with a small number of secretory granules aligned along the cell periphery) only some of the secretory granules that were labeled with anti-ACTH serum were also immunoreactive to anti--MSH. In atypical corticotropes (polygonal in shape and containing a large number of secretory granules) almost all of the immunoreactive ACTH secretory granules were also positive to anti--MSH serum. An intermediate type of corticotrope was observed containing a small number of secretory granules, almost all of which were labeled with anti--MSH. Thus, rat anterior pituitary corticotropes may be classified into three types according to the distribution and content of -MSH. The light-microscopic immuncytochemistry provided similar results.  相似文献   
5.
Summary In a cooperative randomized control study of immunotherapy with bestatin in combination with chemotherapy in adults with acute nonlymphocytic leukemia (ANLL), 101 patients (48 in the bestatin group and 53 in the control group) out of 115 patients registered were evaluated as eligible. The bestatin group achieved a statistically significant prolongation of survival compared with the control group in overall ANLL and acute myelogenous leukemia. In the analysis of patient age, the bestatin group achieved a statistically significant prolongation of both the remission duration and survival in patients aged 50 to 65 years, while the differences were not significant in the 15 to 49 age group. The bestatin group tended to achieve a higher rate of reinduction of remission in patients who had recurrence of leukemia. Side effects developed in only 5 (9.6%) of 52 patients treated with bestatin. None of these side effects were particularly serious in nature. It is concluded that bestatin is useful for prolongation of survival of adult patients with ANLL, making for a longer remission duration especially in elderly patients and with few side effects.  相似文献   
6.
To study the gene products of the HLA complex, we produced two monoclonal antibodies, termed HU-18 and HU-23. They were active in complement-dependent cytotoxicity and detected B-cell alloantigens encoded by a locus (or loci) linked to HLA. When three types of HLA-DR4 homozygous B-cell lines with different HLA-D specificities were tested for reactivity with HU-18 and HU-23, they displayed distinct reaction patterns depending on the HLA-D specificities they possessed: EBV-Wa (HLA-DYT homozygous), negative for both HU-18 and HU-23; KT2 and KOB (HLA-DKT2 homozygous), positive only for HU-18; and ER (HLA-Dw4 homozygous), positive for both. These differential reaction patterns were further confirmed by testing against a panel of 17 HLA-DR4-positive peripheral blood lymphocytes with known HLA-D specificities. Thus, these monoclonal antibodies allow us to identify HLA-DYT, HLA-DKT2, and HLA-Dw4 solely by serologic methods. This is the first clearcut serologic identification of these three HLA-DR4-associated HLA-D specificities, which have been indistinguishable by conventional serology and identified only by cellular techniques. It is hoped that immunochemical investigations using HU-18 and HU-23 will advance our understanding of the HLA-D region on a molecular level.  相似文献   
7.
Summary Persistent estrus and diestrus was produced in rats by the administration of estrone for either 5 days or 30 days, respectively, immediately after birth. Female rats without any treatment were used for control. After these rats grew up, the anterior pituitaries were examined by electron microscopy. The identification criteria for two types of gonadotrophs, FSH-and LH-cells, proposed by Barnes were adopted. In the persistent estrous rats, FSH-gonadotrophs were almost normal, but LH-gonadotrophs were filled with an abundance of secretory granules which were probably suppressed in discharge. On the other hand, in the persistent diestrous rats, FSH-cells were few in number and strongly atrophic, containing a few secretory granules, while LH-cells were almost normal or rather slightly activated. These electron microscopic findings well coincide with the results of light microscopy of ovaries, which suggested that in the persistent estrous rats FSH secretion might be almost normal but the secretion of LH might be inhibited, while in the persistent diestrous rats FSH secretion might be almost totally abolished but LH might be moderately secreted. From these findings, identification of FSH-and LH-gonadotrophs in the anterior pituitary of the rat well coincides with that proposed by Barnes in mice.  相似文献   
8.
The objective of this study was to investigate the in vitro and in vivo developmental abilities of equine embryos cryopreserved by vitrification. Twenty-eight embryos were recovered from Native pony and Thoroughbred mares at Days 5 to 7 by nonsurgical uterine flushing (detection of ovulation=Day 0). The vitrification solution contained 40% ethylene glycol, 18% Ficoll, and 0.3 M sucrose in PBS. The embryos were placed for 1 to 2 min in vitrification solution (Group 1) or following exposure to 20% ethylene glycol in PBS for 10 to 20 min (Groups 2 and 3). Single embryos were loaded in 0.25-ml straws, cooled for 1 min in liquid nitrogen vapor and immersed in liquid nitrogen. Straws were warmed in water (20 degrees C, 20 sec), and the contents were expelled with 0.5 M sucrose in PBS. Then the sucrose was diluted in 1-step (Groups 1 and 2) or 4-steps (Group 3). Embryos (n=21) were cultured for 120 h in TCM199 supplemented with 10% fetal bovine serum at 37 degrees C in 5% CO(2) in air and evaluated morphologically. Development to the hatching or hatched blastocyst stage was obtained in 0 7 , 4 7 and 4 7 embryos in Groups 1, 2 and 3, respectively. An additional 7 embryos were vitrified-warmed according to the treatment of Group 2 (4 embryos) and Group 3 (3 embryos). Five embryos were selected after in vitro culture for 4 h and were transferred nonsurgically into the uterine horn of Day-4 recipient mares. Transfer of 2 embryos (both Day-6 blastocysts: Group-2 treatment) resulted in pregnancies with a viable fetus at Day-60 of the gestation period.  相似文献   
9.
Allo-chimerism and clonal elimination of self antigen (Ag) (Ia + Mls-1a) reactive Vβ6+ T cells were analyzed and compared between allogeneic bone marrow (BM) chimeras reconstituted with BM cells which had been treated with anti-Thy-1 monoclonal antibody (mAb) plus complement (C) (T chimeras) and BM chimeras which had been reconstituted with BM cells pretreated with anti-Thy-1 mAb alone (T+ chimeras). When lethally irradiated AKR (Mls-1a) mice were reconstituted with BM cells from B10 or B10 H-2 congenic mice, both T+ and T chimeras were entirely free of signs of graft-versus-host reaction (GVHR). However, complete replacement of the AKR lymphoid tissues by donor BM cells was accomplished at an early stage in T+ chimeras but not in T chimeras. On the other hand, clonal elimination of Vβ6+ T cells reactive to the recipient Ag (Mls-1a) was abolished in T+ chimeras but successfully induced in T chimeras. The Vβ6+ T cells not eliminated in T+ chimeras showed depressed responses against Mls-1a antigens. The findings herein demonstrate that T cells which contaminate a BM inoculum survive in recipient mice after treatment with anti-Thy-1 mAb without C in vitro followed by BMT. The surviving T cells have been estimated to represent fewer than 0.5% of the BM cells inoculated. These cells appear to accelerate the full replacement of recipient lymphoid tissues by donor cells. Furthermore, the T cells which survive in the marrow inoculum influence eventually the development of a tolerant state in the T cell repertoire of the donor.  相似文献   
10.
A lectin was purified from the bark of Robinia pseudoacaciaby sequential ion-exchange chromatography on DEAE-Sepharoseand CM-Toyopearl. The purified lectin was estimated to havea molecular weight of 106 kDa and to be a homotetramer of subunitswith a molecular weight of 29 kDa. Antibodies raised againstthe bark lectin cross-reacted with a 29-kDa polypeptide duringWestern blot analysis, showing that the antibodies are specificfor the bark lectin. The antibodies against the lectin fromRobinia bark cross-reacted with polypeptides in extracts ofthe seeds and bark of Sophora japonica, indicating that thelectin from Robinia bark is immunologically related to the lectinsof Sophora. However, the antibodies did not cross-react withproteins from Robinia seeds and leaves. The first twenty aminoacid residues from the N-terminus of the lectin from Robiniabark were determined and compared with those of the Sophoralectins. (Received July 13, 1991; Accepted December 12, 1991)  相似文献   
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