Search PubMed⌕ Search

Biomedical subjects

H Murakami

Publications and source records attributed to H Murakami.

At least 379 records · Page 21Linked to original sources
PubMed1995

Steroid-responsive pulmonary disorders associated with myelodysplastic syndromes with der(1q;7p) chromosomal abnormality.

We report three patients with pulmonary disorders associated with myelodysplastic syndromes (MDS). All three patients had symptoms of pyrexia and respiratory discomfort. One patient had pulmonary eosinophilia with bilateral pleural effusion, one had interstitial pneumonia, and one had bilateral pleural effusion caused by systemic vasculitis. Elevated C-reactive protein (CRP) levels, polyclonal hypergammaglobulinemia, and morphological abnormalities in peripheral blood were observed in all three patients. The bone marrow of these patients revealed trilineage dysplasia and eosinophilia. Cytogenetic analysis showed [46,XY,-7,+der(1q;7p)]. Antibiotic treatment was not effective. However, improvement was dramatic after corticosteroid treatment; CRP levels were reduced and the hypergammaglobulinemia was improved. These cases suggest that MDS with [-7,+der(1q;7p)] may be correlated with bone marrow eosinophilia and that an immunologic abnormality may be involved in the pulmonary disorders.

Adrenal Cortex Hormones↗
PubMed1995

Lymph node metastases in carcinoma of the head of the pancreas region.

Histopathological examination of lymph node metastatic involvement in 139 specimens obtained from patients who underwent pancreatoduodenectomy or total pancreatectomy combined with wide resection of lymph nodes was performed, to clarify the critical areas of lymph node dissection in patients with carcinoma of the head of the pancreas region. Perigastric lymph node involvement in patients with carcinoma of the head of the pancreas was 14 per cent, in those with carcinoma of the distal bile duct 0 per cent and in those with carcinoma of the papilla of Vater 4 per cent. Para-aortic lymph node involvement in patients with carcinoma of the head of the pancreas, the distal bile duct and the papilla of Vater was 26, 9 and 0 per cent, respectively. On the basis of these results, pylorus-preserving pancreatoduodenectomy is indicated in almost all patients with carcinoma of the distal bile duct and the papilla of Vater. In patients with carcinoma of the head of the pancreas, however, wide dissection of lymph nodes, including para-aortic lymph nodes, should be carried out because of the relatively high incidence of para-aortic lymph node involvement.

Carcinoma, Ductal, Breast↗
PubMed1995

Possible involvement of focal adhesion kinase, p125FAK, in osteoclastic bone resorption.

Involvement of tyrosine phosphorylation in osteoclastic bone resorption was examined using osteoclast-like multinucleated cells prepared from co-cultures of mouse osteoblastic cells and bone marrow cells in the presence of 1 alpha,25-dihydroxyvitamin D3. When osteoclast-like cells were plated on culture dishes in the presence of 10% fetal bovine serum, they were sharply stained in their peripheral region by anti-phosphotyrosine antibody. Western blot analysis revealed that 115- to 130-kD proteins were tyrosine-phosphorylated in osteoclast-like cells. Using immunoprecipitation and immunoblotting, one of the proteins with 115-130 kD was identified as focal adhesion kinase (p125FAK), a tyrosine kinase, which is localized in focal adhesions. Immunostaining with anti-p125FAK antibody revealed that p125FAK was mainly localized at the periphery of osteoclast-like cells. Herbimycin A, a tyrosine kinase inhibitor, not only suppressed tyrosine phosphorylation of p125FAK but also changed the intracellular localization of p125FAK and disrupted a ringed structure of F-actin-containing podosomes in osteoclast-like cells. Antisense oligodeoxynucleotides to p125FAK inhibited dentine resorption by osteoclast-like cells, whereas sense oligodeoxynucleotides did not. These results suggest that p125FAK is involved in osteoclastic bone resorption and that tyrosine phosphorylation of p125FAK is critical for regulating osteoclast function.

Animals↗
PubMed1995

Longitudinal study of the effect of high intensity weight training on aerobic capacity.

To investigate the effect of a long-term weight lifting programme characterized by high intensity, low repetition and long rest period between sets on maximal oxygen consumption (VO2max) and to determine the advantage of this programme combined with jogging, 26 male untrained students were involved in weight training for a period of 3 years. The VO2max and body composition of the subjects were examined at beginning, 1 year, 2 years (T2), and 3 years after (T3) training. Of the group, 19 subjects performed the weight lifting programme 5 days each week for 3 years (W-group), 4 subjects performed the same weight lifting programme for 3 years with an additional running programme consisting of 2 miles of jogging once a week during the 3rd year (R1-group), and 3 subjects performed the weight lifting programme during the 1st year and the same combined jogging and weight lifting programme as the R1-group during the 2nd and 3rd years (R2-group). The average VO2max relative to their body mass of the W-group decreased significantly during the 1st year, followed by an insignificant decrease in the 2nd year and a levelling off in the 3rd year. The average VO2max of the W-group at T2 and T3 was 44.2 and 44.1 ml.kg-1.min-1, respectively. The tendency of VO2max changes in the R1- and R2-groups was similar to the W-group until they started the jogging programme, after which they recovered significantly to the initial level within a year of including that programme, and they then levelled off during the next year. Lean body mass estimated from skinfold thicknesses had increased by about 8% after 3 years of weight lifting. The maximal muscle strength, defined by total olympic lifts (snatch, and clean and jerk), of these three groups increased significantly and there was no significant difference among the amounts of the increase in the three groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Molecular cloning of the 31 kDa cytosolic phospholipase A2, as an antigen recognized by the lung cancer-specific human monoclonal antibody, AE6F4.

The human monoclonal antibody AE6F4 specifically reacts with human lung cancer tissues but does not with normal tissues. This monoclonal antibody recognizes a cytosolic 31 kDa antigen in the cancer cells. In a previous study, we elucidated that the 31 kDa antigen belonged to a family of proteins collectively designated as 14-3-3 proteins, which were known as protein kinase-dependent activators of tyrosine/trytophan hydroxylases, or protein kinase C inhibitor proteins. Here we report molecular cloning of the 31 kDa antigen from the human lung adenocarcinoma cell line, A549. Sequencing analysis indicates that the cloned cDNA is identical to that of previously reported human placental cytosolic phospholipase A2 (cPLA2), which is also a member of the 14-3-3 protein family. Western analysis demonstrated that a 31 kDa recombinant cPLA2 expressed in monkey COS cells was recognized by the AE6F4 monoclonal antibody. Binding of the monoclonal antibody to the recombinant cPLA2 was abolished when treated with sodium periodate, suggesting that not only are carbohydrate chains associated with the cPLA2, but they also play a crucial role in antigen recognition by the monoclonal antibody.

14-3-3 Proteins↗
PubMed1995

Molecular cloning of yeast cytochrome c-like polypeptide expressed in human lung carcinoma: an antigen recognizable by lung cancer-specific human monoclonal antibody.

We previously determined the amino acid sequence to the epitope (ATLFKTR) of cytochrome c from Candida krusei, which is cross-reactive to the lung cancer-specific human monoclonal antibody HB4C5. Here we report that an antigen messenger RNA, which codes for a structure similar to the cytochrome c epitope, is expressed in the human lung adenocarcinoma A549. Sequencing analysis has revealed that this messenger RNA encodes a novel 190 amino acid polypeptide of 21-kDa containing an amino acid sequence (ALLFFT) similar to the cytochrome c epitope, although the total messenger RNA sequence is apparently different from the cytochrome c messenger RNA. Western analysis indicated that an antibody-recognizable 21-kDa antigen which has the same molecular weight as the predicted polypeptide is expressed in the A549 adenocarcinoma. The in vitro translated product of the antigen messenger RNA and synthesized ALLFFT peptide were both shown to be reactive with the monoclonal antibody, indicating that this protein contains the epitope which enables A549 cells to specifically react with the antibody. The antigen mRNA was not expressed in non-transformed fibroblasts, suggesting that the antigen mRNA expression was associated with cellular transformation. Also in part of the antigen nucleotide sequence, there was a segment that had about 90% homology to the long terminal repeat sequence (no. 297-475) of the human endogenous retrovirus HERV-K10, which was related to the mouse mammary tumor virus.

Adenocarcinoma↗
PubMed1995

Chorda-evoked opening of tight junctions in rat submandibular salivary acini demonstrated by microperoxidase.

The permeability of these junctions from the interstitium to the lumen was examined by using an ultrastructural tracer, microperoxidase, in conjunction with electron microscopy. In the resting gland, the reaction product of microperoxidase was seen in the interstitial and intercellular spaces, but not within acinar lumina; thus the tight junction was impermeable to microperoxidase (junction closed). Intraductal injection of hypertonic sucrose solution (1000 mOsm; 30 microliters) caused a sustained elevation of the luminal pressure, indicating osmotic water flow into the lumen due to the presence of a hypertonic solution. In this gland no opening of the tight junctions was observed. In the chorda-stimulated gland, microperoxidase entered the lumen through the tight junctions, that is, they became permeable to microperoxidase (junction open). These findings suggest that chorda stimulation opens the acinar tight junctions and that the paracellular secretory pathway may be involved in the secretion of small molecules and water from the submandibular acini.

Animals↗
PubMed1995

Detection of O2- generation and neutrophil accumulation in rat lungs after acute necrotizing pancreatitis.

BACKGROUND: Polymorphonuclear neutrophils (PMNs) and PMN-derived superoxide anions (O2-) have been found to mediate acute respiratory distress syndrome (ARDS). But the evidence has been obtained only indirectly, (for example, by treatment with free radical scavengers or by measuring lipid peroxides). METHODS: We used chemiluminescence technique to measure O2- generation directly from the surface of rat lungs with necrotizing pancreatitis. Myeloperoxidase activity in the lung tissue was measured by a new chemiluminescence method to quantitate pulmonary neutrophil sequestration. RESULTS: Transient bursts of chemiluminescence that reflected O2- generation were observed at the lung surface 3 to 5 hours after necrotizing pancreatitis was induced. No O2- dependent chemiluminescence was detected at the lung surfaces of the neutropenic rat made by pretreatment with polyclonal antineutrophil antibody. Myeloperoxidase activity was significantly high (mean, 1690 cell numbers/mg wet tissue) in the necrotizing pancreatitis rat lung (p < 0.005). CONCLUSIONS: These data confirmed that activated neutrophils and neutrophil-derived superoxide anions were implicated in lung injury after acute severe pancreatitis.

Acute Disease↗
PubMed1995

A possible mechanism of the specific action of bisphosphonates on osteoclasts: tiludronate preferentially affects polarized osteoclasts having ruffled borders.

The mechanism of action of tiludronate [(4-chlorophenyl)-thiomethylene bisphosphonate] on osteoclastic bone resorption was examined in mouse culture systems. Tiludronate did not inhibit the formation of osteoclast-like multinucleated cells (OCLs) induced by 1 alpha,25-dihydroxyvitamin D3 in cocultures of mouse osteoblastic cells and bone marrow cells. OCLs obtained from cocultures on collagen gel-coated dishes, treated with tiludronate, formed as many resorption pits on dentine slices as those obtained from the control cocultures. However, pit formation by OCLs was dose-dependently inhibited when tiludronate was added directly to the pit formation assay. Other bisphosphonates such as alendronate and etidronate dose-dependently inhibited pit formation according to the in vivo potencies of the respective bisphosphonates to inhibit bone resorption. However, they had no inhibitory effect on the recruitment of OCLs induced by 1 alpha,25-dihydroxyvitamin D3 in the cocultures. When OCLs were placed on dentine slices, they formed the ringed structure of F-actin-containing podosomes and ruffled borders (polarized OCLs) even in the presence of tiludronate. However, the actin rings in OCLs were disrupted by the addition of tiludronate soon after they began to resorb dentine. In contrast, OCLs placed on collagen gel formed neither actin rings nor ruffled borders (nonpolarized OCLs), and showed no response to tiludronate. OCLs formed from the spleen cells of osteosclerotic (oc/oc) mice developed the ringed structure of podosomes, but not ruffled borders, on dentine slices. The actin ring in the oc/oc spleen cell-derived OCLs placed on dentine slices was not disrupted by the addition of tiludronate.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1995

The small GTP-binding protein, rho p21, is involved in bone resorption by regulating cytoskeletal organization in osteoclasts.

Rho protein (rho p21), a p21ras-related small guanine nucleotide binding protein, regulates cytoskeletal organization in a number of different types of cells. Evidence has indicated that Clostridium botulinum-derived ADP-ribosyltransferase (C3 exoenzyme) specifically ADP-ribosylates rho p21 at Asn41 and renders it functionally inactive. In this study, we examined the involvement of rho p21 in osteoclastic bone resorption using the C3 exoenzyme. When osteoclast-like multinucleated cells obtained from cocultures of mouse osteoblastic cells and bone marrow cells were placed on dentine slices, they formed ringed structures of podosomes containing F-actin (corresponding to the clear zone) within 8 hours. Many resorption pits were formed on dentine slices after culture for 24 hours. The C3 exoenzyme at 0.15-10 micrograms/ml added to the culture medium disrupted the ringed structure of podosomes in osteoclast-like cells in a dose-dependent manner. Correspondingly, pit formation by osteoclast-like cells on dentine slices was dose-dependently inhibited also by adding the C3 exoenzyme. Microinjection of the C3 exoenzyme into osteoclast-like cells placed on culture dishes completely disrupted the ringed podosome structure within 20 minutes. The amount of the rho p21 which was ADP-ribosylated by the C3 exoenzyme in vitro was much greater in purified osteoclast-like cells than in osteoblastic cells. Prior exposure of the purified osteoclast-like cell preparation to the C3 exoenzyme in vivo markedly decreased the amount of unribosylated rho p21. This indicated that the C3 exoenzyme incorporated into osteoclast-like cells effectively ADP-ribosylates rho p21 in vivo.(ABSTRACT TRUNCATED AT 250 WORDS)

Actins↗
PubMed1995

Structural analysis of alkaline-soluble polysaccharide, P-1, from the kernels of Prunus mume Sieb. et Zucc.

A polysaccharide fraction extracted with cold 0.5 M NaOH from the kernels of Prunus mume exhibited some biological activities. A polysaccharide, P-1, was purified from the 0.5M NaOH extract by ion-exchange chromatography and gel-filtration. The results of the structural analysis of P-1 to determine the relationship between the activities and the structure are described in this paper. In the mild acid hydrolysis of P-1, the nondialyzable hydrolysate (I-3) believed to be its core portion was obtained. The yield of I-3 was 26.0% and contained 59.8% uronic acid as galacturonic acid (GalA). The neutral sugars of I-3 were composed of rhamnose, xylose and galactose in a molar ratio of 1.0:3.4:0.3 following analysis by gas-liquid chromatography. The molecular weight of I-3 was estimated to be ca. 14000 by gel-filtration on Toyopearl HW55F. I-3 exhibited the mitogenic activity toward spleen cells as well as P-1. These facts appeared to confirm that I-3 was the core part of P-1 and important for its biological activity. I-3 was successfully reduced by the Taylor and Conrad method to avoid so much repetition. Methylation analysis of the reduced hydrolysate by gas-liquid chromatography and gas chromatography-mass spectroscopy showed that the ratio of 1,4-linked galactopyranosyl and 1,3,4-linked galactopyranosyl residues were significantly increased in comparison with native I-3. These results suggested that I-3 was composed of 1,4- and 1,3,4-linked galacturonic acid residues in the main chain.

Animals↗
PubMed1995

Enhancement of production of IgM and interferon-beta in human cell lines by poly-lysine.

The promotive effects of poly-cations on immunoglobulin production was investigated using human-human hybridoma cells. Among poly-cations tested, epsilon-poly-L-lysine with hydrochloride (approximately 4 kDa), which has been used as an antibacterial food additive, had the greatest activity in enhancing IgM production of human-human hybridoma HB4C5 cells without stimulating cell proliferation. Immunoglobulin production stimulatory (IPS) activity of epsilon-poly-lysine was not affected by trypsin digestion. It was stable below 60 degrees C but completely inactivated with heating at 100 degrees C for 30 min. epsilon-Poly-lysine also enhanced interferon-beta (IFN-beta) production of human osteosarcoma MG-63 cells, but this stimulatory effect was reduced by the trypsin digestion.

Amino Acid Sequence↗
PubMed1995

Ras amplification in BHK-21 cells produces a host cell line for further rapid establishment of recombinant protein hyper-producing cell lines.

To rapidly establish recombinant protein hyper-producing cell lines we introduced a reporter plasmid into BHK-21 cells that had been 'primed' by transfection and amplification of the ras oncogene. The reporter plasmid used carries the human interleukin-6 (hIL-6) gene which is under control of the human cytomegalovirus immediate early promoter. The primed BHK cell lines were shown to produce many stable hIL-6 hyper-producing cells achieving about 15 times higher productivity than the control BHK-21 cells.

Animals↗
PubMed1995

E1A and ras oncogenes synergistically enhance recombinant protein production under control of the cytomegalovirus promoter in BHK-21 cells.

The amplified ras oncogene greatly enhanced the production of recombinant human interleukin-6 (hIL-6) under control of the cytomegalovirus immediate early promoter (CMV promoter) in BHK-21 cells. When the adenovirus E1A oncogene was further transfected into the above mentioned ras-amplified hIL-6 hyperproducing BHK cells, the transfectants had about 10 times higher productivity than non-transfectants. However, the E1A gene alone did not enhance productivity. These results implicate a ras and E1A synergistic ability that acts to enhance hIL-6 production.

Adenoviridae↗
PubMed1995

Development of a protein-free medium with iron salts replacing transferrin for a human-human hybridoma.

Many protein-free media have been developed, because protein-free media are usually more economical than serum-free or serum-containing media and facilitate the purification of bioactive materials. We evaluated various iron salts and chelating agents replacing transferrin to develop a protein-free medium for a human-human hybridoma, HB4C5, and found out that ferric citrate was favorable for the production and the productivity of monoclonal antibodies.

Antibodies, Monoclonal↗
PubMed1995

Premature termination mutation (772Glu-->stop) in the hormone-binding domain of the androgen receptor in a patient with the receptor-negative form of complete androgen insensitivity syndrome.

We have characterized the androgen receptor in a Japanese infant with complete androgen insensitivity syndrome (or androgen resistance), and have investigated the molecular basis. Androgen binding was undetectable in cultured genital skin fibroblasts from this patient by whole-cell androgen receptor binding assay. Sequence analysis of the entire coding region of the androgen receptor gene from this patient revealed a single nucleotide substitution (G-->T) at nucleotide position 2676 in exon E (or 5), resulting in conversion of glutamine codon (GAG) to amber stop codon (TAG) at amino acid position 772 within the hormone-binding domain of the androgen receptor. This premature termination mutation (or nonsense mutation), introducing a truncated androgen receptor that lacks most of its androgen binding capacity, is though to cause the receptor-negative form of complete androgen insensitivity syndrome in this patient.

Base Sequence↗