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Biomedical subjects

M Nishida

Publications and source records attributed to M Nishida.

At least 289 records · Page 16Linked to original sources
PubMed1995

[Heterogeneity of lipopolysaccharide chain size of Pseudomonas aeruginosa isolated from different clinical sources--with reference to gentamicin-susceptibility and serotype].

Lipopolysaccharide (LPS) compositions of P. aeruginosa isolated from from clinical sources such as blood, urine, pus, sputum, and feces were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and aminoglycoside-susceptibility and serotype of these isolates were investigated in this study. Fifty-nine isolates tested were divided into three groups according to the difference in their LPS compositions; 35 strains with the long-LPS chain (B-band LPS), 14 strains with the short chain (A-band LPS) and 10 LPS-deficient strains. The relationship between the LPS compositions and their sources of 59 strains were investigated. The majority of clinical isolates (12 of the 13 strains) from the blood samples possessed the long-LPS chain (B-band LPS) and the remaining possessed the short-LPS chain (A-band LPS). About 67% each of the isolates from urine and feces possessed the long-LPS chain, and the minor part of both groups possessed the short-LPS chain. In isolates from both sputum and pus samples, the long- and short-LPS chains were found at almost the same rate, and the LPS-deficient isolates were found in the sputum samples at a considerably high rate of 42%. The 19 of the 35 isolates with the long-LPS chain were susceptible to gentamicin (54%) and 12 isolates were resistant (34%). On the other hand, the 14 isolates with the short chain were divided roughly into three groups, gentamicin-resistant, and -susceptible groups and intermediate groups. It was also notable that 7 of the 10 LPS-deficient isolates were resistant to gentamicin.(ABSTRACT TRUNCATED AT 250 WORDS)

Drug Resistance, Microbial↗
PubMed1995

Localization of heparin-binding EGF-like growth factor in the smooth muscle cells and macrophages of human atherosclerotic plaques.

Heparin-binding EGF-like growth factor (HB-EGF) is a potent chemoattractant and mitogen for smooth muscle cells (SMC) in culture. To elucidate whether HB-EGF is implicated in the pathogenesis of human atherosclerosis, we examined immunohistochemical localization of HB-EGF in human aortic walls and atherosclerotic plaques. The medial SMC of the aorta in babies and children synthesized HB-EGF protein, while the number of SMC producing HB-EGF was dramatically decreased in young and middle-aged adults. In atherosclerotic plaques, however, marked production of HB-EGF protein was detected in SMC and macrophages of the plaques. Furthermore, EGF receptors, to which HB-EGF is known to bind, were detected in plaque SMC. These data suggest that HB-EGF may be implicated in the migration and proliferation of SMC that occurs in the normal development of arterial walls, and in the formation of atherosclerotic plaques.

Adult↗
PubMed1995

New tumor clips for the removal of large or deep-seated tumors: technical note.

We describe newly developed tumor-holding clips, which have been applied in more than 50 patients with large or deep-seated tumors. We devised various kinds of standard tumor clips by modifying Sugita aneurysm clips. Our new tumor clips permit gentle, steady, and easy retraction of the tumor in any direction without disturbance of the operative field. With the use of these clips, a surgeon can operate with both hands. From our experience of removing more than 50 tumors, we confirm that our tumor clips are useful for the removal of large or deep-seated tumors.

Brain Neoplasms↗
PubMed1995

Synthesis of saframycins. X. Transformation of (-)-saframycin A to (-)-saframycin Mx type compound with the structure proposed for saframycin E.

Treatment of (-)-saframycin A (1a) with selenium oxide in acetic acid afforded (-)-saframycin G (1g), and a catalytic reduction and regioselective oxidation sequence afforded the saframycin Mx type compound (3). We applied this methodology to the transformation of (+/-)-5-hydroxysaframycin B (11) to the hydroquinone (1e). Acetylation of 1e with acetic anhydride in pyridine gave the triacetate (13), which is identical with the triacetyl derivative of natural saframycin E.

Anti-Bacterial Agents↗
PubMed1995

Nitric oxide synthase protects the heart against ischemia-reperfusion injury in rabbits.

The role of nitric oxide (NO) in myocardial ischemia-reperfusion injury is still controversial. To determine the role of NO in the propagation of myocardial injury in a coronary artery occlusion-reperfusion model, we examined the effect of a competitive NO synthase inhibitor, NG-nitro-L-arginine methyl ester (L-NAME), with and without L-arginine, on the size of the infarct resulting from coronary artery occlusion (30 min) followed by reperfusion (48 hr) in rabbits. L-NAME (300 micrograms/kg, as a bolus, and 100 micrograms/kg/min, i.v.) with and without L-arginine (30 mg/kg, as a bolus, and 10 mg/kg/min, i.v.) was administered immediately before coronary occlusion to 60 min after reperfusion. The infarct size in the L-NAME-treated rabbits (75.1% +/- 5.0%, n = 7), assessed as a percentage of infarcted region/ischemic region, was significantly larger than that of control rabbits (51.2% +/- 7.4%, n = 7; P < .05). The increase in infarct size was significantly attenuated by the treatment with L-NAME and L-arginine (62.0% +/- 4.0%, n = 7). However, the infarct size for the treatment with L-NAME and D-arginine (76.7% +/- 5.7%, n = 6) did not differ from that in the L-NAME-treated rabbits. There was no significant difference in the infarct size between L-arginine-treated (60.1% +/- 7.3%, n = 6) and control rabbits. Rate-pressure products, as an index of myocardial oxygen consumption, were comparable in all the groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Oxidoreductases↗
PubMed1995

[Effects of inhaled beclomethasone on height growth and bone metabolism in children with asthma].

To evaluate the influences of inhaled beclomethasone dipropionate (BDP), 7.3-30.9 (15.5 +/- 6.5) micrograms/kg/day, on bone metabolism and height growth, we performed a longitudinal study for 6 months in 34 children with asthma aged between 3 and 15 years. Bone mineral density estimated by digital image processing method (DIP) and serum level of osteocalcin did not show any significant change, but height growth was slightly suppressed in the patients who inhaled more than 15 micrograms/kg/day of BDP. We concluded that the decision to prescribe inhaled BDP should be made on the balance of the clinical effects and the improvement of quality of life against the possibility of side effects.

Administration, Inhalation↗
PubMed1995

[Analysis of familial aggregation of ovarian and breast cancer in patients with ovarian cancer].

In 118 patients with common epithelial ovarian tumors (carcinomas and tumors of borderline malignancy) treated at Tsukuba University Hospital and Tsukuba-Gakuen Hospital, family histories of ovarian and breast cancer were obtained from medical records or in interviews, and familial aggregation of these cancers was examined. 1. A positive family history was found in 10 patients (8.5%). The high incidences of familial ovarian cancer and ovarian cancer in patients who were previously affected with breast cancer were statistically significant. 2. Patients with serous adenocarcinoma showed a significantly greater rate of positive family history than those with mucinous adenocarcinoma. 3. No significant correlation was seen between the clinical stage and a positive family history. 4. Every patient except one with a positive family history had onset of ovarian cancer after menopause. The age at onset for familial ovarian cancer cases was younger than that for the patients' relatives who were affected previously. 5. There were 14 healthy women considered to be at high risk for ovarian cancer among 5 familial ovarian and 2 familial ovarian and breast cancer aggregations. These preliminary findings suggest that screening for early ovarian cancer should be conducted in high risk relatives of familial cancer patients and women affected with breast cancer previously. More detailed studies are needed to define the occurrence of familial or hereditary ovarian and breast cancers in Japan.

Adenocarcinoma, Mucinous↗
PubMed1995

[An immunohistological study on expression of glutathione S-transferase pi (form) in human ovarian carcinoma].

Specimens from 102 cases of ovarian cancer were stained immunohistochemically with a rabbit polyclonal antibody prepared against the placental form of the enzyme glutathione S-transferase (GST-pi). All 28 cases of mucinous adenocarcinoma, 19 of clear cell carcinoma and 4 of malignant transformed dermoid cysts were stained positively with the GST-pi antibody. These tumors are considered to be resistant to chemotherapeutic agents as compared with other epithelial tumors. With regard to the histological grade, the degree of staining was reduced according to the loss of differentiation. An investigation of the relationship between GST-pi stain and the prognosis of the 50 patients with stage 2,3 or 4, according to the Kaplan-Meier method, revealed that the prognosis improved as the staining decreased. In conclusion, results suggested that immunohistochemical staining of GST-pi is correlated with the chemoresistance of the tumor, and may predict the outcome in patients with ovarian cancer.

Adenocarcinoma, Clear Cell↗
PubMed1995

[A case of renal cell carcinoma in a young adult].

Renal cell carcinoma in young adults under the age of forty is rare. A case of renal cell carcinoma in a 22-year-old female is presented. Microhematuria was pointed out in the patient by a health check up system and an ultrasonogram revealed a solid mass 5 cm in diameter in the lower pole of the right kidney. The patient was referred to our clinic in January, 1994. An abdominal CT showed a solid and well bordered mass in the right kidney. Renal tumor biopsy was revealed renal cell carcinoma. Right radical nephrectomy was performed on February 9, 1994. From 1986 to 1994, 4 cases of renal cell carcinoma in young adults, other than this case, have been treated in our clinic. All of them have been healthy for more than 6 years, suggesting a good prognosis.

Adult↗
PubMed1995

[Establishment of a cisplatin-resistant new human endometrial adenocarcinoma cell line, Sawano cells].

A new human endometrial adenocarcinoma cell line, Sawano cells, was established from an endometrial adenocarcinoma from a 61-year-old woman and has been maintained in vitro for more than 2 years and 10 months. The cells were found to form a monolayer in a mosaic fashion and to tend to pile up. Population doubling time was 43.2 hours at the 10th generation. The modal chromosomal number of the cell fell in a diploid range. Histology of the tumor induced in athymic mice showed it to be a moderately differentiated adenocarcinoma which closely resembled the original human tumor. Estrogen and progesterone receptors were not demonstrated in the in vitro culture cells and in the tumors induced in nude mice, though they were positively demonstrated in the original tumor. The cells had intrinsic cisplatin-resistance (50% inhibition concentration:6.63 micrograms/ml) at 120 hours of contact. We believe this cell line with help us to investigate the biological mechanisms of CDDP resistance.

Adenocarcinoma↗
PubMed1995

Platelet-activating factor induces cell growth through tyrosine phosphorylation pathway in cultured rat mesangial cells.

Accumulating evidence suggests that platelet-activating factor (PAF) may play a role in renal pathophysiology. Therefore, in order to investigate this notion further, the effects of PAF on cell growth and tyrosine phosphorylation were analyzed in cultured rat mesangial cells. PAF was found to enhance a time and concentration-dependent increase in phosphotyrosine in several proteins and stimulate 3H-thymidine incorporation. Tyrosine phosphorylation was also enhanced by PAF in protein kinase C (PKC) depleted cells, whereas a tyrosine kinase inhibitor, genistein, inhibited tyrosine phosphorylation of these proteins at the concentration of 1 microgram/ml. PAF stimulated 3H-thymidine incorporation at concentrations below 10(-6) M, but exerted progressive inhibition at concentrations above 10(-6) M. Pre-treatment with phorbol 12-myristate 13-acetate (PMA) did not affect PAF-enhanced incorporation at lower concentrations of PAF, and reversed the inhibitory effects of PAF at higher concentrations. Finally, genistein pre-treatment completely inhibited PAF-induced cell growth at the concentration of 1 microgram/ml. Both tyrosine phosphorylation and 3H-thymidine incorporation induced by PAF were completely inhibited by pre-treatment with the PAF-receptor antagonist, CV-6209, at the concentration of 10(-5)M. These results suggest that PAF enhancement of tyrosine phosphorylation occurred in a PKC-independent manner and that a tyrosine kinase was associated with PAF-induced tyrosine phosphorylation. Moreover, they indicate that the phosphoinositide hydrolysis-PKC pathway is not essential for PAF-induced cell proliferation, and that PKC activation may play an inhibitory rather than a stimulatory role in mitogenesis in response to PAF. Our results indicate that the tyrosine phosphorylation pathway induced by PAF may participate critically in downstream mitogenic signaling through the PAF receptor.

Animals↗
PubMed1995

[Carrier detection and prenatal diagnosis for hemophilia A using the inversion analysis of the factor VIII gene].

Hemophilia A is an X-linked hemorrhagic disorder caused by heterogeneous mutations in the factor VIII gene. Recently, it was reported that approximately 50% of the cases of severe hemophilia A may be caused by a common inversion in the factor VIII gene. In this study, we analyzed 33 Japanese patients with severe hemophilia A for the presence of this inversion mutation using the non-RI Southern blotting, and detected inversion mutations of the factor VIII gene in 12 patients (36.4%). We also showed that the inversion analysis of the factor VIII gene was useful for carrier detection and prenatal diagnosis in a hemophilia A family, which we had not been able to diagnose by the analysis of restriction fragment length polymorphisms (RFLPs) of the factor VIII gene. The detection of inversion mutations in the factor VIII gene using non-RI Southern blotting analysis appears to be very useful for the genetic counseling for severe hemophilia A.

Adult↗
PubMed1995

[Establishment of a new human endometrial adenocarcinoma cell line, Watanabe cells, containing estrogen receptor].

A new human endometrial adenocarcinoma cell line, Watanabe cells, was established from the ascitic fluid of a relapsed endometrial adenocarcinoma obtained from a 58-year-old woman; this cell line has been maintained in vitro for more than 3 years and 8 months. The cells formed a monolayer in a mosaic fashion and tended to pile up and formed a hemicyst. The population boubling time was 60.0 hours at the 10th generation. The modal chromosomal number of the cells was in the diploid range. The histology of tumors induced by this cell line in athymic nude mice showed poorly differentiated adenocarcinoma, while the initial tumor was a well differentiated adenocarcinoma. Estrogen and progesterone receptors (ER, PR) were demonstrated in the original tumor, whereas ER but not PR were present in the tumors induced in nude mice. CA125, CA19-9 and other tumor markers were positive in culture media of this cell line. The cells showed intrinsic cisplatin-resistance (50% inhibition concentration: > 10 micrograms/ml) at 120 hours of exposure by MTT assay. We believe this cell line will be useful for investigating the mechanisms of progesterone therapy, the biological behaviors of the tumor markers and mechanisms of chemotherapeutic resistance in endometrial carcinoma.

Adenocarcinoma↗
PubMed1994

The Urinary Excretion of Pyridinium Cross-links as Markers of Bone Meta stasisin Breast Cancer.

The collagen cross-links, pyridinoline (Pyr) and deoxypyridinoline (D-Pyr) excreted in urine have recently been suggested as new markers of bone metastasis. In a pilot study we measured Pyr and D-Pyr in 61 patients with breast cancer, 16 with known bone metastasis and 45 with no recognized metastasis in bone. Twenty healthy female subjects were also measured as controls. The mean values (+/-SD) of Pyr and D-Pyr in the group with bone metastasis were significantly higher (Pyr: p<0.01, D-Pyr: p <0.05) than those in the group without bone metastasis and in the control group. The mean (+/-SD) values of postmenopausal women were significantly higher than those of premenopausal in the group without bone metastasis (p<0.05) and in the control group (p<0.01). Therefore, the effect of menopause should be taken into account in the diagnosis of bone metastasis by assays of Pyr and D-Pyr. Setting the cut-off values (mean + 2SD of the values of control) for pre and postmenopausal patients, the accuracy for Pyr was 71.4% in premenopausal and 75.8% in postmenopausal patients; and for D-Pyr it was 71.4% and 78.8% respectively. We consider that measurement of urinary collagen cross-links assays can contribute to the early detection of metastatic spread to bone in breast cancer.

Journal Article↗
PubMed1994

Molecular cloning and site-directed mutagenesis of glutathione S-transferase from Escherichia coli. The conserved tyrosyl residue near the N terminus is not essential for catalysis.

Glutathione S-transferase (GST) was purified from Escherichia coli K-12, and its N-terminal sequence was determined to be MKLFYKPGAXSLAS. The gene encoding this sequence was cloned and mapped at 1731-1732 kilobases on the E. coli gene map. It encoded a polypeptide of 201 amino acid residues with a calculated molecular weight of 22,860. The overexpressed product of the gene was confirmed to have GST activity toward 1-chloro-2,4-dinitrobenzene and ethacrynic acid and GSH-dependent peroxidase activity toward cumene hydroperoxide. The relative molecular mass of the gene product was determined to be 40,000 by gel chromatography and 25,000 by SDS-polyacrylamide gel electrophoresis, indicating a homodimeric structure. The deduced amino acid sequence was 54% identical with that of Proteus mirabilis GST. Although the homologies between the GSTs from E. coli and mammals were low, many of the residues assigned to be important for the enzymatic function or structure in mammalian cytosolic GSTs were found to be conserved in E. coli GST. Therefore, E. coli GST is considered to have diverged from the same ancestor with other cytosolic GSTs. A specific tyrosyl residue in the vicinity of the N terminus is conserved in all of the known cytosolic GSTs and has been shown to function as a catalytic residue in alpha, mu, and pi class GSTs from mammals. Although Tyr5 in E. coli GST appeared to be the counterpart of the catalytic residue, its replacement with phenylalanine did not significantly affect the enzymatic activity. Therefore, this apparently conserved tyrosyl residue is not essential for catalytic activity in E. coli GST.

Amino Acid Sequence↗
PubMed1994

Developmental changes of neurotrophin-3 level in the mouse brain detected by a highly sensitive enzyme immunoassay.

Levels of neurotrophin-3 (NT-3) in the mouse brain were measured by a highly sensitive enzyme immunoassay (EIA). The monoclonal antibody, 3W3, was labeled with beta-galactosidase, followed by measurement of galactosidase activity. The detection limit of the EIA system was 0.4 pg/well (4 pg/ml). At 1 and 8 weeks of age, the highest level of NT-3 was detected in the hippocampus, a relatively high level also observed in the cerebellum. In contrast, in the cortex, the striatum, the diencephalon, the midbrain, and the brainstem, NT-3 levels were low. Furthermore, we examined the developmental changes of NT-3 level in the hippocampus and the cerebellum. In the hippocampus, the NT-3 levels were more than 20 ng/g tissue from 1 week to 14 weeks of age, but at 20 weeks of age the level decreased to about half. In the cerebellum, although the NT-3 level was high at 1 week of age, the levels were gradually decreased to one-fourth by 20 weeks of age. In peripheral tissues, a large amount of NT-3 protein was observed in the heart.

Animals↗
PubMed1994

gamma-Glutamylcysteine ethyl ester for myocardial protection in dogs during ischemia and reperfusion.

OBJECTIVES: The aim of this study was to examine the infarct-limiting effects of gamma-glutamylcysteine ethyl ester, a newly discovered synthetic precursor of glutathione biosynthesis, in a canine model of myocardial infarction. BACKGROUND: Reduced glutathione plays an important role in protecting cells against damage induced by reactive oxygen species during myocardial ischemia and reperfusion. Gamma-glutamylcysteine ethyl ester is capable of penetrating into cells in its intact form and increasing intracellular glutathione levels. METHODS: Dogs were subjected to a 90-min coronary occlusion followed by 5 h of reperfusion. An intravenous bolus injection of gamma-glutamylcysteine ethyl ester (3 or 10 mg/kg body weight) was administered immediately before reperfusion. Regional myocardial blood flow was measured with the use of colored microspheres. RESULTS: Gamma-glutamylcysteine ethyl ester effectively reduced infarct size in a dose-dependent manner (mean +/- SEM 26.4 +/- 3.5% in the low dose group [3 mg/kg, n = 10] and 19.0 +/- 3.4% in the high dose group [10 mg/kg, n = 10]; each p < 0.05 vs. the value in the control group [40.6 +/- 4.8%, n = 10]). There were no differences between the control and treated groups in hemodynamic variables or regional myocardial blood flow either during the ischemic period or after reperfusion. The reduced glutathione content of ischemic myocardium in the control group (0.62 +/- 0.11 mumol/g, p < 0.01) was significantly lower than that in nonischemic myocardium (1.46 +/- 0.07 mumol/g), and it was preserved by treatment in a dose-dependent manner (3 mg/kg, 0.83 +/- 0.06 mumol/g; 10 mg/kg, 0.92 +/- 0.14 mumol/g; each p < 0.05 vs. control level). There were no differences in oxidized glutathione content between nonischemic and ischemic myocardium or among the three groups. CONCLUSIONS: Gamma-glutamylcysteine ethyl ester, a precursor of glutathione, significantly attenuates myocardial ischemia and reperfusion injury when administered immediately before reperfusion.

Animals↗