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Biomedical subjects

H Muramatsu

Publications and source records attributed to H Muramatsu.

At least 91 records · Page 5Linked to original sources
PubMed2000

Midkine expression in Reed-Sternberg cells of Hodgkin's disease.

Midkine (MK) was originally cloned as a product of a retinoic acid-responsive gene. The rationale for studying MK expression is based on previous reports showing that it transforms 3T3 cells, and that it acts as an autocrine growth factor in Wilm's tumors, and that its overexpression has been associated with worse outcome in bladder carcinoma. Besides bladder carcinoma, its expression was reported in various solid tumors. We investigated the expression of MK protein and/or MK gene in biopsied specimens from 40 patients with primary malignant lymphoma, 21 with Hodgkin's disease (HD) and 19 with non-Hodgkin's lymphoma (NHL). Reed-Sternberg (R-S) cells were stained positive in 10 of 16 HD cases evaluated by immunohistochemical method, whereas 18 of 19 NHL cases did not stain, and one B-cell NHL stained weakly positive. Immunostaining analysis was extended to established cell lines and to normal lymphocytes with or without lectin stimulation or with EB virus transformation. Among hematopoietic cells examined, erythro- or megakaryoblastic leukemia cell lines (K562, MEG-01 and UT7) were positive, while normal lymphocytes (except the EB virus-transformed one) and most myeloid and lymphoid cell lines (except Raji cells) were negative. On the contrary, solid tumor cell lines showed high and strongly positive staining including cell lines derived from of lung gastric, colon, and a pancreatic cancer. Using semi-quantitative reverse transcription polymerase chain reaction (RT-PCR), which is suitable for the detection of weakly expressed mRNA, the relative ratio of MK mRNA to beta-actin mRNA of samples was measured and compared in cases where RNA was available. The mean values of relative ratio (MK/beta-actin) of HD were almost twice as those of NHL samples, peripheral blood T cells, and spleen B cells. Our findings showed that MK is expressed in Reed-Sternberg cells of HD, and that MK might play a role in the pathogenesis of HD.

Animals↗
PubMed2000

[Student nurses' views on the usefulness of psychology].

It has been said for a long time that psychology is very important and useful for nursing. And, due to specialization in medicine and aging of society, the importance and usefulness of psychological knowledge for the nurses have increased even more. However, it has not been made clear what sort of psychological knowledge is useful for nursing process and what ought to be taught in the lectures on psychology in the nursing school. In this paper, 173 student nurses rated the usefulness of 75 major propositions of psychology. The results revealed that especially the areas of motivation, consciousness, physiological psychology, and clinical psychology were recognized as very useful, although all areas of psychology taken up in this research were rated as useful. The results also revealed that these areas could be classified into 5 factors, that is, basic psychology, understanding of human behavior, understanding of mental condition, understanding of matters directly related to medicine, and cognition. It is expected that these results are taken into account so that the lectures on psychology are useful for the nurses.

Adult↗
PubMed2000

A new antimitotic substance, FR182877. I. Taxonomy, fermentation, isolation, physico-chemical properties and biological activities.

Using the characteristic morphological changes of mammalian cells, we screened novel antimitotic substances and found that a strain of Streptomyces sp. No.9885 produced FR182877. This substance was isolated from the culture broth by ethyl acetate extraction, silica gel column chromatography and ODS column chromatography. Structural studies on FR182877 suggested that it had a unique hexacyclic structure encompassing its highly strained double bond. FR182877 exhibited potent antitumor activities against murine ascitic tumor and solid tumor in vivo.

Animals↗
PubMed2000

FR901469, a novel antifungal antibiotic from an unidentified fungus No.11243. I. Taxonomy, fermentation, isolation, physico-chemical properties and biological properties.

FR901469 is a novel antifungal antibiotic produced by an unidentified fungus No.11243. This compound was isolated from the culture broth by solvent extraction, HP-20 and YMC ODS gel column chromatography, and lyophilization. FR901469 is a white powder which melts at 182 approximately 187 degrees C and possesses the molecular formula C71H116N14O23. This compound has good water solubility. FR901469 inhibited the activity of 1,3-beta-glucan synthase from Candida albicans with an IC50 value of 0.05 microg/ml, and displayed greater inhibitory activity than other 1,3-beta-glucan synthase inhibitors such as, WF11899A, echinocandin B, aculeacin A, and papulacandin B.

Animals↗
PubMed2000

FR901469, a novel antifungal antibiotic from an unidentified fungus No.11243. II. In vitro and in vivo activities.

FR901469 is a water-soluble macrocyclic lipopeptidolactone (C71H116N14O23) that has inhibitory activity against 1,3-beta-glucan synthase and exhibits in vitro and in vivo antifungal activity against both Candida albicans and Aspergillus fumigatus. The MICs of FR901469 against Candida albicans FP633 and Aspergillus fumigatus FP1305 in a micro-broth dilution test were 0.63 and 0.16 microg/ml, respectively. FR901469 showed excellent efficacy by subcutaneous injection against both Candida albicans and Aspergillus fumigatus in a murine systemic infection mode, with ED50s of 0.32 and 0.2 mg/kg, respectively. This compound also showed potent anti-Pneumocystis activity in the nude mice model with experimental Pneumocystis pneumonia. The hemolytic activity of FR901469 towards mouse red blood cells, is about 30-fold weaker than that of amphotericin B.

Animals↗
PubMed2000

Cyclooxygenase-2 inhibitor induces apoptosis and enhances cytotoxicity of various anticancer agents in non-small cell lung cancer cell lines.

In recent years, a combination of two demographic phenomena, an increase in the number of older people in the population and an increase in the incidence of lung cancer with age, has made it mandatory to develop therapeutic modalities with less toxicity for the treatment of inoperable elderly patients with lung cancer. Our study shows that a cyclooxygenase (COX)-2 inhibitor, nimesulide, can inhibit proliferation of non-small cell lung cancer cell lines in vitro in a dose-dependent manner, in part by inducing apoptosis even at clinically achievable low concentrations. Our observations also suggest that the responsiveness of non-small cell lung cancer to COX-2 inhibitors does not require the presence of wild-type p53, but may be influenced by the degree of COX-2 expression. In addition, we found that nimesulide, when used in combination at clinically achievable concentrations, reduced the IC50 values of various anticancer agents by up to 77%, although the level of reduction varied considerably. Because our previous studies have indicated a significantly increased COX-2 expression in up to 70% of adenocarcinoma cases, the present findings are of great clinical interest. In conjunction with the recent development of next generation, highly selective COX-2 inhibitors, they can be expected to lead to even greater efficacy of their use as adjuncts to various anticancer agents for the treatment of high-risk patients without compromising their quality of life.

Antineoplastic Agents↗
PubMed1999

Is radiosensitive cell line cross-sensitive to heat?: Effect of heat on two rat yolk sac tumor cell lines with different radiosensitivity.

The differences between two rat yolk sac tumor cell lines, which are of the same origin but differ in their response to irradiation, in thermal sensitivity and development of thermotolerance were investigated. A radiosensitive cell line NMT-1 is consistently less heat sensitive than the radioresistant cell line NMT-1R. The thermotolerances in NMT-1 and in NMT-1R preheated at 43 degrees C for 30 min, respectively, reached peaks at 6 h and at 12 h, but did not completely disappear at 48 h. Thermotolerance with a good correlation between both cell lines with HSP70 accumulation was observed in a different time course after a primary heating.

Animals↗
PubMed1999

Delayed administration of ethyl eicosapentate improves local cerebral blood flow and metabolism without affecting infarct volumes in the rat focal ischemic model.

The objective of this study was to assess whether delayed administration of ethyl eicosapentate has a favorable effect on cerebral blood flow and metabolism in rats suffering from cerebral infarction. Adult male Sprague-Dawley rats weighing 250-300 g were used. Left middle cerebral artery occlusion was induced for 2 h. After 24-h reperfusion, rats were treated with ethyl eicosapentate (100 mg kg(-1); ethyl eicosapentate treated) or saline (saline treated) by gavage, once a day for 4 weeks. After 4 weeks, local cerebral blood flow and local cerebral glucose utilization were measured autoradiographically, and infarction size was measured. In the ischemic side, the local cerebral blood flow and local cerebral glucose utilization values in the parietal cortex and the lateral caudoputamen, which constituted the ischemic core, were equivalent to zero in both groups. The peri-infarcted areas, i.e., the frontal cortex and medial caudoputamen, were significantly higher in the ethyl eicosapentate treated group than the saline treated group. In the non-ischemic side, ethyl eicosapentate treated group had a tendency to improve local cerebral blood flow and local cerebral glucose utilization values in a medial caudoputamen. These results suggest that ethyl eicosapentate treatment may be beneficial for maintaining cerebral circulation and metabolism except for infarction area after cerebral infarction.

Animals↗
PubMed1999

Intraluminal increase of superoxide anion following transient focal cerebral ischemia in rats.

Using a modification of Karnovsky's Mn2+/diaminobenzizine (DAB) technique, we examined the production of superoxide anion (.O-2) in the vascular lumen following transient occlusion and reperfusion of the left middle cerebral artery (MCA) in Sprague-Dawley rats. The MCA was occluded for 2 h using an intraluminal suture method. Zero, 15, 30, and 60 min after reperfusion, animals were perfused transcardially with buffer containing Mn2+ and DAB, and brain samples were prepared for light and electron microscopic examination. The amber reaction deposits of.O-2 were observable to the naked eye along the major cerebral vessels of the ischemic hemisphere after each reperfusion period. Upon microscopic examination the deposits were revealed to be within arterial, capillary, and venular lumen. The amount of reaction deposits in the ischemic hemisphere corresponded to the duration of reperfusion. The formation of.O-2 was suppressed when the perfusate contained superoxide dismutase and when either Mn2+ or DAB was omitted, confirming that the reaction products produced are due to the enhanced production of.O-2. These results show that there is a progressive increase in intraluminal. O-2 during reperfusion following an ischemic insult which may participate in the aggravation of cerebral damage.

Animals↗
PubMed1999

Expression of midkine in normal and burn sites of rat skin.

Expression of midkine (MK), a retinoic acid-inducible heparin binding growth factor, was examined immunohistochemically in normal and burn sites of rat skin. In the normal skin, MK was localized in the epidermis and dermal appendages such as hair follicles and sebaceous glands. Mast cells in the subdermal connective tissue also accumulated MK. After burn injury, MK-positive cells began to infiltrate into subdermal connective tissue, and the number of MK-positive cells in the region increased to a maximum at postburn day two and then decreased gradually. Western blotting analysis of both normal and postburn skin revealed a 30 kDa band reactive with anti-MK antibody; this band was concluded to be a dimer of MK. These findings were discussed from the viewpoint of the possible role of MK in wound healing.

Animals↗
PubMed1999

Three-dimensional microstructural analysis of human trabecular bone in relation to its mechanical properties.

The purpose of this preliminary study is to explore the relationship between elastic modulus, bone mineral density (BMD), and trabecular microstructure in three dimensions. Twenty cubes of trabecular bone were processed from two lumbar vertebrae obtained from one individual. The BMD of each cube was measured by dual-energy X-ray absorptiometry and peripheral quantitative computed tomography. Each cube was serially scanned by microcomputed tomography to produce three-dimensional data sets. By analyzing these data sets, three-dimensional trabecular microstructural indices of connectivity density and fractal dimension were calculated as well as histomorphometric parameters. The cubes were tested mechanically in a nondestructive manner for measurement of their elastic modulus. This preliminary study showed that: (1) bone mass index is correlated with mechanical properties, with coefficients of correlation ranging from 0.552 to 0.601; and (2) when controlling for BMD, no association could be detected between measures of structural complexity (connectivity density and fractal dimension) and elastic modulus in the craniocaudal direction of human vertebral bodies.

Biomechanical Phenomena↗
PubMed1999

Enhanced inhibition of experimental metastasis by the combination chemotherapy of Cu-Zn SOD and adriamycin.

We previously reported that reactive oxygen species (ROS) enhance tumor cell metastasis, and by administration of recombinant human superoxide dismutase (rh SOD), an enzyme which scavenges O2- successfully reduced lung metastasis of mouse MethA sarcoma and Lewis lung carcinoma. These observations suggested that rh SOD suppressed tumor cell invasion by eliminating O2- the primary source of ROS. However, for the clinical application of the drug as an anti metastatic agent, rh SOD needs to be administered in combination with other cytotoxic agents, since SOD by itself has no cytotoxic activity. In this paper, we investigated the effectiveness of the combination chemotherapy of rh SOD and adriamycin (ADR), an anti-cancer agent against the experimental metastasis of highly metastatic clone, MH-02, which was derived from murine Meth A sarcoma. The present metastasis experiment clearly indicates that the administration of rh SOD enhances the antimetastatic effect of ADR. On the other hand, we found that the inhibition rate of metastasis exhibited by the combination chemotherapy of rh SOD and a certain dose (5 mg/ml) of ADR was inferior to that of rh SOD. This apparent paradoxical phenomenon was presumably explained by our finding that tumor cells themselves augment their invasive capacity and platelet aggregation, both of which are causative factors for metastasis formation, by generation of O2- when they were treated with ADR. Nevertheless, the combination chemotherapy of SOD with anticancer drugs such as ADR can be a practical anti-metastasis strategy.

Animals↗
PubMed1999

Spatially and temporally regulated expression of N-acetylglucosamine-6-O-sulfotransferase during mouse embryogenesis.

GlcNAc-6-O-sulfotransferase is involved in formation of 6-sulfo-N -acetyllactosamine-containing structures such as 6-sulfo sialyl Lewis x. We investigated the mode of expression of GlcNAc-6-O-sulfotransferase during postimplantation embryogenesis in the mouse by in situ hybridization. Sulfotransferase mRNA was not detected on embryonic day (E) 6.5, while on E7.5 it was detected in the mesoderm, ectoderm, and ectoplacental cone. On E10.5, the sulfotransferase signals were mainly observed in the nervous tissue. On E12.5 and 13.5, various tissues in the process of differentiation expressed this mRNA. Several epithelial and mesenchymal tissues undergoing epithelial-mesenchymal interactions strongly expressed the mRNA. For example, in the developing tooth strong sulfotransferase mRNA expression was found only in the condensing mesenchyme on E13.5. On E13.5 and 15.5, the sites showing intense expression of the sulfotransferase again became restricted. In the brain, sulfotransferase mRNA was frequently found as discrete signals in narrow regions. These results suggest that 6-sulfo-N-acetyllactosamine structures have important roles in development. On E13.5 and 15.5, G152 (6-sulfo sialyl Lewis x antigen) was expressed in the neocortex, and AG223 (6-sulfo Lewis x antigen) in the thalamus and neocortex where the sulfotransferase signal was detected. However, in other organs, expression of these antigens did not correlate with the sulfotransferase mRNA, implicating complex nature of regulation of expression of the fucosyl 6-sulfo antigens.

Animals↗
PubMed1999

Survey of 222Rn concentrations in the air of a tunnel located in Nagano City using the solid-state nuclear track detector method.

The survey of 222Rn concentration in the air of tunnels constructed during World War II has been performed using a solid-state nuclear track detector technique. For the practical application of this technique to the determination of 222Rn concentrations in air, some basic properties were experimentally examined on the cellulose nitrate film, Kodak LR 115 type II. The calibration coefficient of the cellulose nitrate film used is determined from a correlation between the 222Rn concentration in air and the observed number of perforated etched tracks for widespread radon concentrations. The slope of the linear relationship observed yields a calibration coefficient of (0.00209 +/- 0.00018) tracks cm(-2) (Bq m(-3) h)(-1). From the survey of 222Rn concentration in the air of tunnels, the concentration of several thousand Bq m(-3) was observed at the inner most area of the tunnel, and the seasonal variation was clearly observed. The exponential distribution of radon concentration as a function of distance from the openings of the tunnel suggests that the radon concentration in the tunnel is basically governed by diffusion and mixing of radon gas with air.

Air Pollutants, Radioactive↗
PubMed1999

Midkine is expressed during repair of bone fracture and promotes chondrogenesis.

Midkine (MK) is a heparin-binding growth/differentiation factor implicated in the control of development and repair of various tissues. Upon fracture of the murine tibia, MK was found to be transiently expressed during bone repair. MK was immunohistochemically detected in spindle-shaped mesenchymal cells at the fracture site on day 4 after fracture and in chondrocytes in the area of endochondral ossification on day 7. MK expression was decreased on day 14 and scarcely seen on day 28 when bone repair was completed. This mode of MK expression is reminiscent of MK expression during development. MK was expressed in hypertrophic chondrocytes of the prebone cartilage rudiments on embryonic day 14 in mouse embryos. MK was also strongly expressed in the epiphyseal growth plate. MK was localized intracellularly during both bone repair and development, and this localization was confirmed by immunoelectron microscopy for embryonic chondrocytes. When MK cDNA was transfected into ATDC5 chondrogenic cells and overexpressed, the majority of transfected cells with strong MK expression showed enhanced chondrogenesis as revealed by increased synthesis of sulfated glycosaminoglycans, aggrecan, and type II collagen. These results suggest that MK plays important roles in chondrogenesis and contributes to bone formation and repair.

Aggrecans↗
PubMed1999

[Bronchiectasis].

Obstructive impairment of pulmonary function in bronchiectasis depends on the number of segments involved in the bronchiectatic process and severity of the morphologic abnormalities in the region of the dilated bronchi. There is no obstructive change in bronchiectasis with single segmental lesion without fatal cases with multiple dilatation of bronchi. Immotile cilia syndrome, Kartagener syndrome, diffuse panbronchiolitis and cystic fibrosis can result from a multitude of heredity were observed in the obstructive impairment. A case of panbronchiolitis obliterans with diffuse cystic dilatation of bronchi due to mycoplasma pneumoniae infection was presented in severe obstructive disturbance.

Bronchi↗