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M Fujino

Publications and source records attributed to M Fujino.

At least 91 records · Page 5Linked to original sources
PubMed1998

A prolactin-releasing peptide in the brain.

Hypothalamic peptide hormones regulate the secretion of most of the anterior pituitary hormones, that is, growth hormone, follicle-stimulating hormone, luteinizing hormone, thyroid-stimulating hormone and adrenocorticotropin. These peptides do not regulate the secretion of prolactin, at least in a specific manner, however. The peptides act through specific receptors, which are referred to as seven-transmembrane-domain receptors or G-protein-coupled receptors. Although prolactin is important in pregnancy and lactation in mammals, and is involved in the development of the mammary glands and the promotion of milk synthesis, a specific prolactin-releasing hormone has remained unknown. Here we identify a potent candidate for such a hormone. We first proposed that there may still be unknown peptide hormone factors that control pituitary function through seven-transmembrane-domain receptors. We isolated the complementary DNA encoding an 'orphan' receptor (that is, one for which the ligand is unknown). This receptor, hGR3, is specifically expressed in the human pituitary. We then searched for the hGR3 ligand in the hypothalamus and identified a new peptide, which shares no sequence similarity with known peptides and proteins, as an endogenous ligand. We show that this ligand is a potent prolactin-releasing factor for rat anterior pituitary cells; we have therefore named this peptide prolactin-releasing peptide.

Amino Acid Sequence↗
PubMed1998

p53 and Bcl-2 expression in pneumoconiosis-related pre-cancerous lesions and lung cancers: frequent and preferential p53 expression in pneumoconiotic bronchiolar dysplasias.

To explore the mechanism by which lung cancers excessively arise from pneumoconiosis, we determined the altered expression of p53 and Bcl-2 by immunohistochemistry (IHC) in lung cancers, dysplasias and non-cancerous pulmonary epithelia in pneumoconiotics in comparison with those from non-pneumoconiotic patients. We examined p53 expression in squamous cell carcinomas (SCCs) and dysplasias separately in the central and peripheral zones of bronchial trees, based on observations that SCCs from pneumoconiotic patients occurr more frequently in peripheral epithelia than those from non-pneumoconiotic patients (55 of 72 SCCs with pneumoconiosis vs. 33 of 72 SCCs without pneumoconiosis). Forty-one of 72 patients with pneumoconiosis-related lung cancers had altered p53 expression, which was comparable to the positivity of p53 expression in lung cancers without pneumoconiosis. p53 expression was observed significantly more frequently in bronchiolar dysplasias with pneumoconiosis than in those from non-pneumoconiotic patients (13 of 23 vs. 4 of 22), while p53 expression was found in bronchial dysplasias with pneumoconiosis as frequently as those without pneumoconiosis. Moreover, in patients with pneumoconiosis, bronchiolar dysplasias exhibited p53 expression more frequently than bronchial dysplasias (13 of 23 vs. 4 of 19). When comparison was restricted to bronchiolar dysplasias from patients without lung cancer, p53 expression had a strikingly higher frequency in the dysplasias with pneumoconiosis than in those from non-pneumoconiotic patients (8 of 15 vs. 0 of 14). Bcl-2 occasionally was expressed in squamous metaplasias and basal cell hyperplasias, in contrast to p53, for which immunostaining was negative in these lesions. Altogether, our results show that pre-cancerous and/or cancerous targets in pneumoconiosis may be distributed over a more peripheral zone than those in patients without pneumoconiosis.

Bronchi↗
PubMed1998

Transition state in the folding of alpha-lactalbumin probed by the 6-120 disulfide bond.

The guanidine hydrochloride concentration dependence of the folding and unfolding rate constants of a derivative of alpha-lactalbumin, in which the 6-120 disulfide bond is selectively reduced and S-carboxymethylated, was measured and compared with that of disulfide-intact alpha-lactalbumin. The concentration dependence of the folding and unfolding rate constants was analyzed on the basis of the two alternative models, the intermediate-controlled folding model and the multiple-pathway folding model, that we had proposed previously. All of the data supported the multiple-pathway folding model. Therefore, the molten globule state that accumulates at an early stage of folding of alpha-lactalbumin is not an obligatory intermediate. The cleavage of the 6-120 disulfide bond resulted in acceleration of unfolding without changing the refolding rate, indicating that the loop closed by the 6-120 disulfide bond is unfolded in the transition state. It is theoretically shown that the chain entropy gain on removing the cross-link from a random coil chain with helical stretches can be comparable to that from an entirely random chain. Therefore, the present result is not inconsistent with the known structure in the molten globule intermediate. Based on this result and other knowledge obtained so far, the structure in the transition state of the folding reaction of alpha-lactalbumin is discussed.

Animals↗
PubMed1998

Efficient Fas-ligand gene expression in rodent liver after intravenous injection of a recombinant adenovirus by the use of a Cre-mediated switching system.

An adenovirus vector AxCALNFasL was constructed in order to transduce a gene for rat Fas-ligand, requiring co-expression of Cre recombinase for its expression. In the cosmid cassette, pAxCALNFasL, a stuffer DNA fragment flanked with two loxP sequences was placed between the promoter and Fas-ligand cDNA to prevent its expression in transfected 293 cells. COS-7 cells infected with AxCALNFasL alone did not induce apoptosis in cocultivated Jurkat cells, but the cells treated with AxCALNFasL and AxCANCre (an adenovirus expressing Cre recombinase with the CAG promoter) did. BALB/c mice injected with 10(9) plaque-forming units of AxCALNFasL and with different doses of AxCANCre, developed lethal acute liver failure. The number of the apoptotic hepatocytes increased dramatically with increased doses of injected AxCANCre, indicating that the level of transgene expression in the rodent liver appeared to be adjustable. Based on these observations, we conclude that vectors expressing a gene to produce cytotoxic substances can be constructed by the use of a Cre-mediated switching system. Our system also demonstrated that efficient expression of the toxic gene in the rodent liver was achievable by co-infection of adenovirus vectors carrying the target gene and Cre recombinase.

Adenoviridae↗
PubMed1998

Sex differences in marital and social adjustment.

A sample of 67 married Japanese men and 79 married Japanese women, ranging in age from 25 through 85 years, were interviewed to clarify the relationship between marital adjustment and social adjustment. For the whole sample, the total score of the Short Marital Adjustment Test (SMAT; Locke & Wallace, 1959) and its subcategories, dyadic consensus and satisfaction, was significantly correlated with 5 subcategory scores of the Social Adjustment Scale-II (SAS-II; Weissman, 1978): household adjustment (except the spouse), external family adjustment, work adjustment, social leisure adjustment, and general adjustment. These correlations were present also for the women; for the men, they were present only for social leisure adjustment and general adjustment. Among men, the dyadic consensus scores of the SMAT had stronger correlations with the social adjustment scores; among women, correlations with the marital satisfaction scores of the SMAT were stronger. Thus, marital adjustment may be a part of social adjustment for women, but the two may be discrete for men.

Adult↗
PubMed1998

Phosphorylation of sic1, a cyclin-dependent kinase (Cdk) inhibitor, by Cdk including Pho85 kinase is required for its prompt degradation.

In the yeast Saccharomyces cerevisiae, Sic1, an inhibitor of Clb-Cdc28 kinases, must be phosphorylated and degraded in G1 for cells to initiate DNA replication, and Cln-Cdc28 kinase appears to be primarily responsible for phosphorylation of Sic1. The Pho85 kinase is a yeast cyclin-dependent kinase (Cdk), which is not essential for cell growth unless both CLN1 and CLN2 are absent. We demonstrate that Pho85, when complexed with Pcl1, a G1 cyclin homologue, can phosphorylate Sic1 in vitro, and that Sic1 appears to be more stable in pho85Delta cells. Three consensus Cdk phosphorylation sites present in Sic1 are phosphorylated in vivo, and two of them are required for prompt degradation of the inhibitor. Pho85 and other G1 Cdks appear to phosphorylate Sic1 at different sites in vivo. Thus at least two distinct Cdks can participate in phosphorylation of Sic1 and may therefore regulate progression through G1.

CDC28 Protein Kinase, S cerevisiae↗
PubMed1998

Synthesis of new peptides with prolactin-releasing activity by a combination of recombinant DNA technology and a cysteine-specific cyanylation reaction.

A newly isolated peptide from bovine hypothalamus with prolactin-releasing activity (prolactin-releasing peptide; PrRP) was synthesized by a combination of recombinant DNA technology and a cysteine-specific cyanylation reaction, together with rat and human homologs. The peptides were expressed in the form of fusion proteins with basic fibroblast growth factor mutein, which were purified by heparin-affinity chromatography. The fusion proteins were cleaved at the cysteine residues of the junction site by cyanylation, followed by treatment with ammonia for C-terminal amidation. Purification of the resulting crude peptides was performed using chromatography on a gel-filtration column, a cation-exchange column, and a reversed-phase column. As an example, about 90 mg of bovine PrRP (bPrRP) was obtained from 201 of culture bloth. The purified b PrRP showed full biological activities in binding to its receptor expressed on CHO cells and releasing arachidonic acid metabolite from the same cells, while the C-terminal acid form of bPrRP had little of these activities. These results indicate that the C-terminal amide structure is very important for expressing biological activity. The peptides obtained here might be very useful for studies on their biological significance and roles in vivo.

Amino Acid Sequence↗
PubMed1998

Development of an enzyme-linked immunosorbent assay using recombinant chicken anemia virus proteins expressed in a baculovirus vector system.

Recombinant baculoviruses were constructed to express the putative proteins VP1, VP2 or VP3 of the chicken anemia virus (CAV). The recombinant VP1, VP2 or VP3 were detected by SDS-PAGE, and their molecular weights were 50, 30/27 and 16 kDa, respectively. The VP2 and VP3 reacted with sera from CAV-infected chickens in Western blot analysis and when used as an enzyme-linked immunosorbent assay (ELISA) antigen, but VP1 did not. Antibodies to CAV were detected, by ELISA using crude insect cell lysates containing VP2 or VP3, from 2 to 20 weeks or 2 to 7 weeks after CAV infection, respectively. These findings indicate that recombinant VP2 and VP3 expressed in the baculovirus vector system can be used as antigens to detect anti-CAV antibodies in ELISA.

Animals↗
PubMed1998

Fas-mediated apoptosis is involved in the elimination of gene-transduced hepatocytes with E1/E3-deleted adenoviral vectors.

Gene-transduced hepatocytes with E1/E3-deleted adenoviral vectors are eliminated immediately and the expression of transduced genes disappears rapidly following the vector administration. In this report, we analysed the involvement of apoptotic cell death in the elimination of hepatocytes infected with adenoviral vectors. An E1/E3-deleted adenoviral vector expressing Escherichia coli beta-galactosidase (LacZ) was injected via the portal vein into congenitally Fas-deficient mice (lpr), Fas ligand-deficient mice (gld) and their control mice, MRL and C3H. 5-Bromo-4-chloro-3-indolyl-beta-D-galactoside (X-gal) staining of the liver specimens showed that 80-100% of hepatocytes were LacZ positive at 7 days after virus administration, suggesting that most of the hepatocytes received the injected adenoviral vectors. In normal mice, the number of LacZ-positive cells decreased dramatically at 14 and 21 days after transduction and few positive cells were observed at day 28. Beta-galactosidase activity, quantified by the O-nitrophenyl-beta-D-galactopyranoside assay, gave comparable results to X-gal staining. At days 14 or 21, many apoptotic hepatocytes and apoptotic infiltrating cells were detected with the terminal deoxyribonucleotidyl transferase-mediated dUTP-digoxigenin nick end-labelling (TUNEL) in situ apoptosis detection method. This observation suggested that the apoptotic process was associated with the elimination of adenovirus-infected hepatocytes. To test the involvement of the Fas-Fas ligand interaction in this apoptotic process, the period of transgene expression was measured in lpr and gld mice, which had received the same amount of AxCALacZ. X-Gal histochemical analysis detected many LacZ-positive cells in lpr or gld mice liver even at 21 or 28 days after AxCALacZ injection. There were significant differences in the reduction rates of beta-galactosidase activity of liver homogenates between lpr and MRL, or gld and C3H mice. Based on these observations, we conclude that the Fas-mediated apoptotic process is involved in the elimination of hepatocytes infected with E1/E3-deleted adenoviral vectors.

Adenoviridae↗
PubMed1997

Ki-67 labeling indices in non-small cell lung cancer: comparison between image cytometry and flow cytometry.

Expression of the proliferation-associated nuclear antigen Ki-67 was studied in 27 human non-small cell lung cancers (NSCLCs). We measured immunohistochemical Ki-67 labeling indices using image cytometry (ICM) and flow cytometry (FCM) and compared the indices determined with the two methods. Ki-67 labeling indices of tumor cells ranged from 2% to 59% with ICM, and from 3% to 56% with FCM, varying from case to case. There was a linear correlation of values between the two methods (r = 0.77, P < 0.05). To examine whether Ki-67 labeling indices represent tumor proliferative activity, we studied the relationship between the Ki-67 labeling index and the S-phase fraction determined by FCM. There was a positive correlation between the Ki-67 labeling index and the S-phase fraction (r = 0.91, P < 0.01). Comparison of Ki-67 labeling indices and clinicopathological parameters showed lower Ki-67 labeling indices in well-differentiated tumors than in moderate and poorly differentiated tumors (P < 0.05). No correlation was observed between Ki-67 labeling indices and p53 expression. It was concluded that the Ki-67 labeling index was in fact measured with both ICM and FCM, and that it represents tumor proliferative activity of NSCLCs.

Adenocarcinoma↗
PubMed1997

Altered retinoblastoma protein expression in nonsmall cell lung cancer: its synergistic effects with altered ras and p53 protein status on prognosis.

BACKGROUND: Inactivation of the retinoblastoma (Rb) gene has been documented in various types of cancer, including lung cancer. Alterations of the p53 and ras genes are also common features in the molecular biology of lung carcinoma, and the authors of this article have reported previously on the prognostic significance of both of them. In the present study, the authors evaluated the prognostic significance of the loss of Rb protein expression alone, then performed a combined analysis of Rb protein and ras p21 status (Rb/ras) as well as an analysis of Rb and p53 protein status (Rb/p53) in patients with nonsmall cell lung cancer (NSCLC). METHODS: Ninety-one patients with NSCLC underwent potentially curative resection between 1977 and 1988, 65 of whom received postoperative combination chemotherapy. Tumor specimens were analyzed for Rb protein expression by immunohistochemistry. Univariate and multivariate analyses were performed to assess the association between Rb protein expression and survival. RESULTS: Nineteen (21%) of the 91 NSCLCs showed negative Rb protein expression. Positive or negative Rb protein expression (Rb+ or Rb-) as an individual factor was not statistically correlated with survival or prognosis in this cohort of NSCLC patients, although a tendency among Rb- patients to do worse was observed. The authors then combined the Rb protein status with previously studied results of ras p21 and p53 protein expression in the same tumor specimens, and compared the prognosis between the individuals with theoretically the best pattern of gene expression in their tumors and those with theoretically the worst pattern of expression, i.e., Rb+/ras- versus Rb-/ras+ and Rb+/p53- versus Rb-/p53+. In patients with adenocarcinoma, those with Rb-/ras+ tumors survived for a significantly shorter period after surgery (13% 5-year survival) than those with Rb+/ras- tumors (82% 5-year survival) (P = 0.01). Similarly, patients with Rb-/p53+ tumors survived for a significantly shorter period (20% 5-year survival) compared with those who had Rb+/p53- tumors (73% 5-year survival) (P = 0.008). Rb/ras status was a significant prognostic factor (P = 0.02 by univariate analysis, P = 0.048 by multivariate analysis), and Rb/p53 status tended to be significant as a prognostic factor (P = 0.04 by univariate analysis, P = 0.08 by multivariate analysis). In patients with squamous cell carcinoma, neither Rb/ras nor Rb/p53 status was a significant prognostic factor in this cohort. CONCLUSIONS: These results suggest that combined immunohistochemical analyses of Rb and ras p21 proteins and of Rb and p53 proteins may indicate their potentially synergistic effects on survival and prognosis. These analyses may also be useful for stratifying patients with adenocarcinoma of the lung into different prognostic groups and identifying populations with different risks of recurrence. Larger prospective studies with Stage I NSCLC patients are necessary to confirm the current findings.

Adenocarcinoma↗
PubMed1997

Identification and characterization of a novel human cortistatin-like peptide.

Expressed sequence tags (ESTs) that showed significant homology to rat cortistatin (CST) were found in a human fetal brain cDNA library. A protein coded by the cDNA showed 55% identity to rat preprocortistatin in amino acid. Similarly in the generation of mature peptides from rat preprocortistatin, it was expected that cleavage at dibasic amino acids in the C-terminal portion of the coded protein might produce at least two different sizes of mature peptides with 29 and 17 amino acid residues, respectively. We chemically synthesized the predicted mature peptide with 17 amino acid residues (hCS-17) and examined its biological activities. It bound to all human somatostatin receptor (SSTR) subtypes in almost the same manner as rat CST-14. It also inhibited cAMP production induced by forskolin through SSTRs. Administration of hCS-17 to the cerebral ventricle showed flattening of cortical and hippocampal electroencephalograms in rats. These results indicate that a bioactive peptide encoded by the cDNA is a human counterpart corresponding to rat CST.

Amino Acid Sequence↗
PubMed1997

Histomorphometric evaluation of the thin hydroxyapatite layer formed through anodization followed by hydrothermal treatment.

By the previously described method of electrochemical and hydrothermal reaction, a thin hydroxyapatite (HA) layer of 1 microm thickness was formed on machined, grit-blasted, and titanium plasma-sprayed implants, the surfaces of which were equipped with a gap zone of 0.15 mm in depth. These implants, together with HA and titanium plasma-sprayed implants as control materials, were placed in dog mandibles for 4 weeks. Histomorphometrical comparison was performed to examine the effects of the thin HA layer and the surface topography on bone formation. The roughened implants, especially the grit-blasted implants, were surrounded with thin bone newly formed along the rough surfaces and showed higher bone apposition than the smooth implants. The gap zone of the HA plasma-sprayed implant was repaired with new bone that had vertically extended from the surrounding bone. The thin HA layer had as much osteoconduction as a plasma-sprayed HA coating but showed significantly different bone response. The results suggest that bone formation on an HA film is affected by degradation in living tissue that is related to the crystallinity and the chemical composition of the HA film itself.

Animals↗
PubMed1997

Reduction of the DTH response is related to morphological changes of Langerhans cells in mice exposed to acute immobilization stress.

There is a large body of evidence indicating that stress influences immune competence. For example, psoriasis and atopic dermatitis may be exacerbated by psychic stress and related to abnormalities in the cellular constituents of the immune system in the skin. However, the underlying mechanisms remain unclear. We therefore investigated the potential of acute immobilization stress to affect the DTH response in BALB/c mice. DTH was significantly reduced in an immobilization time-dependent manner when stress exposure was just before sensitization. Although the number of Langerhans cells (LC) did not change under these conditions, marked alteration of LC morphology was observed with a significant decrease in area. Recovery of LC was observed within 24 h when the DTH response was also restored. Expression of the calcitonin gene-related peptide (CGRP), which inhibits LC antigen presentation, was significantly increased up to 1.6-fold in nerve fibres of immobilized mice. We conclude that stress-induced suppression of DTH could be due to reduction of LC antigen presentation with morphological change in association with CGRP elevation.

Acute Disease↗
PubMed1997

Monoclonal antibodies against mouse splenic stromal cells.

A panel of rat monoclonal antibodies directed against mouse splenic stromal cells were isolated. These monoclonal antibodies were immunohistochemically divided into four groups which reacted with non-lymphoid cells of the murine spleen; (I) in the white pulp, (II) at the marginal zone, (III) in the red pulp, and (IV) on the endothelium of splenic blood vessels. These monoclonal antibodies were studied immunohistochemically in lymphoid organs by means of light and electron microscopy. Monoclonal antibodies SS-4 (group I) reacted with fibroblastic reticulum cells that were distributed only in the white pulp of the spleen and in the follicular areas of lymph nodes. The SS-4 staining cell, in clustered splenic stromal cells, formed colonies which included a small number of Thy-1 positive lymphocytes. Therefore, we concluded that SS-4 staining stromal cells comprise the lymphoid compartment. In contrast, monoclonal antibodies SS-1, SS-3 and SS-5 (group II) reacted with dendritic shaped cells in the marginal zone of the spleen. Examination of splenic extramedullary hematopoiesis in mice rescued by bone marrow transplantation after lethal irradiation revealed that SS-3 and SS-5 reacted with dendritic shaped stromal cells in clonal nodules of engrafted marrow in the red pulp. SS-3 and SS-5 staining cells could not be observed in physiologic hematopoiesis of non-transplanted mice. It was suggested that SS-3 and SS-5 staining stromal cells are involved in primitive hematopoiesis. Monoclonal antibodies SS-2, SS-6 and SS-7 (group III) mainly reacted with dendritic cells and macrophages in the red pulp. Monoclonal antibodies SS-B and SS-9 (group IV) reacted with endothelial cells of blood vessels and sinuses. These findings of heterogeneity in mouse splenic stromal cells are further evidence that specific micro-environments are composed by specialized stromal cells.

Animals↗
PubMed1997

[Sasumata(U+I) shape skin incision for the surgery through median sternotomy].

Since April, 1994 we have tried median sternotomy in a new skin incision which resembles to "Sasumata", a Japanese historical weapon of police, for the surgery of eleven patients with thymic disease or lung cancer for cosmetic reasons. An U-shaped skin incision in the upper half portion of the breast and a vertical incision from the bottom of "U" to xyphoid process were made. A comparison was made in eight patients with former conventional method, a linear incision on the sternum. The new incision was useful not only for cosmetic reasons but also for the following reasons; enough operation area, good lymph node dissection from lower neck to upper mediastinum without additional collar incision, and good healing of the skin. There were no differences between the two incision groups on operation time, bleeding volume and hospital stay after surgery. In a postoperative research almost all patients have been satisfied with the new incision.

Adult↗