Search PubMed⌕ Search

Biomedical subjects

S Adachi

Publications and source records attributed to S Adachi.

At least 163 records · Page 9Linked to original sources
PubMed1996

Methotrexate inhibits superoxide production and chemotaxis in neutrophils activated by granulocyte colony-stimulating factor.

Treatment of circulating human neutrophils with recombinant human granulocyte colony-stimulating factor (rhG-CSF) for 30 min augmented superoxide generation and chemotaxis induced by N-formylmethionyl-leucyl-phenylalanine (fMLP) in a dose dependent manner. When neutrophils were treated with 1 microM of methotrexate (MTX) for 60 min after incubation with rhG-CSF (10 ng/ml), the effects of rhG-CSF on superoxide generation and chemotaxis were inhibited by approximately 49 and 29%, respectively. Although inhibitory effects of MTX were also seen in neutrophils not pretreated with rhG-CSF, the degree of inhibition was much less. The addition of either hypoxanthine or guanosine at a concentration of 100 microM to the culture medium significantly attenuated the effects of MTX. However, in neutrophils obtained from a patient with Lesch-Nyhan syndrome, which lacked hypoxanthine-guanine phosphoribosyl transferase activity neither hypoxanthine nor guanosine had any rescue effect. These results suggest that MTX inhibits superoxide generation and chemotaxis in rhG-CSF-activated neutrophils, at least in part, by disturbing purine nucleotide biosynthesis.

Cells, Cultured↗
PubMed1996

Mild hypoxia induces hypertrophy of cultured neonatal rat cardiomyocytes: a possible endogenous endothelin-1-mediated mechanism.

Hypoxic or ischemic stresses on cardiomyocytes may cause a variety of compensatory responses including cell hypertrophy. In this study, we examined whether hypoxia induces hypertrophy of cardiomyocytes in vitro and whether hypoxia-induced hypertrophy is inhibited by an endothelin A receptor antagonist (BQ123). Neonatal rat cardiomyocytes were cultured in 10% O2/85% N2/5% CO2 or 95% N2/5% CO2 to produce a mild or severe hypoxic condition, respectively. Cardiomyocytes exposed to severe hypoxia revealed degenerative morphological changes and a decrease of cell number, suggesting the toxicity of severe hypoxia on cardiomyocytes. In contrast, cardiomyocytes with mild hypoxia developed hypertrophy; cell surface area of cardiomyocytes as evaluated by an image analyser system increased by 1.6-fold over control after 48 h. [3H]leucine incorporation into the cells was significantly increased by mild hypoxia but decreased by severe hypoxia, mRNA level of skeletal alpha-actin, a genetic marker of cardiac hypertrophy, up-regulated after 6-24 h by mild hypoxia. A transient increase of preproET-1 mRNA and a time-dependent increase of ET-1 protein in the culture medium were also observed in cardiomyocytes exposed to mild hypoxia. BQ123 partially inhibited either hypoxia-induced [3H]leucine incorporation or skeletal alpha-actin mRNA in a dose-dependent manner. These data suggest that mild hypoxia induces hypertrophy of cardiomyocytes and that activation of endogenous ET-1 may, at least in part, mediate this hypertrophic responses as an autocrine/ paracrine factor.

Actins↗
PubMed1996

A small mucinous cystadenocarcinoma of the liver detected by a fluid-fluid level on ultrasonography.

A case of small, borderline malignant biliary mucinous cystic tumor is presented. The patient initially presented to us 18 months earlier to undergo a sigmoid colon resection for sigmoid colon cancer. At that time, a liver cyst measuring 18 x 12 mm was detected. On a follow-up abdominal ultrasonography study for colon cancer, the liver cyst had enlarged to 21 mm in diameter and contained a fluid-fluid level 18 months after surgery. Histological examination of a needle biopsy specimen indicated possible adenocarcinoma. Lateral segmentectomy of the liver was performed. Histopathologically, the tumor was diagnosed as a mucinous cystic tumor, of border line malignancy, which had originated from a bile duct gland. It contained both mucinous and serous components, which were thought to have caused the formation of a fluid-fluid level within the cyst. In this case, the fluid-fluid level demonstrated by ultrasonography was beneficial in the early detection of a cystic tumor of the liver. This case may be the smallest reported cystadenocarcinoma of the liver yet published.

Aged↗
PubMed1996

Synthesis of alanine and leucine by reductive amination of 2-oxoic acid with combination of hydrogenase and dehydrogenase.

Alanine synthesis by reductive amination of pyruvate was performed by the combination of NADH regeneration system and alanine dehydrogenase (AlaDH). The conversion of pyruvate to alanine was 99% after 1 h. Leucine synthesis was also carried out by the combination of NADH regeneration system and leucine dehydrogenase (LeuDH). The conversion of 4-methyl-2-oxovalerate to leucine was 60% after 1.5 h.

Alanine↗
PubMed1996

A rare case of burn scar malignancy.

Malignant changes in burn scars have long been reported in the literature. Most cases are squamous cell carcinomas and some other epithelial cell carcinomas. Soft tissue tumours are considered rare. A rare case of sarcoma arising in a scar on the sole of the foot in a 64-year-old male is reported. He had suffered fire burns 25 years previously. Histological findings indicated that the tumour was a pleomorphic liposarcoma. Amputation was performed, but he died 3 months after the operation. To our knowledge, this is only the second case of liposarcoma developing in a burn scar.

Burns↗
PubMed1996

[Clinical isolates of group B streptococci from elderly patients].

The importance of Group B streptococcal infection in elderly patients has not been clearly defined. We studied the annual incidence of Group B streptococci (GBS) isolated from sputum and urine of elderly patients who were admitted to Nagoyashi Koseiin Geriatric Hospital. The percentage of GBS isolated has increased since 1988. The type distribution of GBS isolates shows predominantly types Ia, Ib and JM9. The major clinical factors in patients from whom GBS was isolated from sputum were bedridden status, feeding tubes and tracheostomy. We also investigated the antibody to GBS in these elderly patients. The titers of GBS antibody were significantly higher in the group with GBS isolates than in the group without these pathogens. These results suggest that GBS is one of the causative organisms of nosocomial infections in elderly patients.

Aged↗
PubMed1996

Pharmacological characteristics of indoline derivatives in muscarinic receptor subtypes.

The present study was designed to investigate which muscarinic receptors the indoline derivatives interact with and also their pharmacological properties. Compounds I and II contracted guinea-pig ileum in a concentration-dependent manner, whereas compounds III-IX behaved as antagonists and Schild plots gave straight lines. 4-DAMP antagonized the contractile responses to compounds I and II, and the pA2 values for 4-DAMP were 8.96 +/- 0.23 and 9.09 +/- 0.06, respectively. In guinea-pig left atrium, compound I partly inhibited twitch responses, whereas compound II did not have any effect. In rabbit vas deferens, compounds I and II produced inhibitory effects on twitch responses evoked by field stimulation. Pirenzepine antagonized the inhibitory responses of compounds I and II, and the pA2 values for pirenzepine were 7.90 +/- 0.13 and 8.12 +/- 0.06, respectively. Compound I has about 150-fold higher affinity to M1 receptors than to M3 receptors, while compound II has about 360-fold higher affinity to M1 receptors. Our results indicate that compounds I and II show 7- and 16-fold higher M1 receptor selectivity than McN-A-343, respectively. Therefore, compound II is selective for M1 receptors over M2 or M3 receptors.

(4-(m-Chlorophenylcarbamoyloxy)-2-butynyl)trimethy↗
PubMed1996

Value of the staged segmental crossclamp to the aorta technique and reimplantation of intercostal arteries for the prevention of spinal complications associated with surgery for descending and thoraco-abdominal aortic aneurysms.

Spinal complication associated with descending and thoracoabdominal aortic aneurysm surgery is most serious. This report deals with the value of the segmental crossclamp technique and/or reimplantation of intercostal arteries for the prevention of this serious complication. The subjects were 107 patients, 87 with descending thoracic and 21 with thoracoabdominal aortic aneurysm who were operated on from May 1987 to March 1992 at the National Cardiovascular Center in Osaka. The staged segmental crossclamp technique was applied in 24, while the reconstruction of intercostal arteries was undertaken in 25 patients. Thirteen patients received both procedures simultaneously. The surgical and hospital mortality rates were 1.8% and 8.4%, respectively. Spinal complications were encountered in 11 patients (8.3%), paraplegia in 2 (1.8%) and paralysis in 7 (6.5%). The incidence of paraplegia or paralysis did not decrease under the crossclamp technique and/or reimplantation of intercostal arteries, although no spinal complication was observed in the last consecutive 33 cases. It was speculated that although advances in surgical techniques in dealing with these lesions have been obtained, these two procedures did not completely prevent spinal ischemia/complication during surgical intervention.

Aorta↗
PubMed1996

Molecular cloning of the cDNAs encoding pituitary glycoprotein hormone alpha- and gonadotropin II beta-subunits of the Japanese eel, Anguilla japonica, and increase in their mRNAs during ovarian development induced by injection of chum salmon pituitary homogenate.

cDNAs encoding the glycoprotein hormone alpha- and gonadotropin (GTH) II beta-subunits of Japanese eel (Anguilla japonica) pituitary were cloned using the polymerase chain reaction. The nucleotide sequence of the glycoprotein hormone alpha-subunit cDNA was 364 base pairs (bp) long, encoding 117 amino acids, and that of the GTH II beta-subunit cDNA was 433 bp long, encoding 140 amino acids. The deduced amino acid sequence of each mature subunit showed high homology with those of other teleosts, indicating that the structure of GTH subunits has been conserved during the evolution of teleosts. Changes in the expression of these subunit genes during ovarian development induced artificially by the injection of chum salmon pituitary homogenate were examined using Northern blot analysis. Glycoprotein hormone alpha-subunit mRNA increased almost linearly during ovarian development, whereas GTH II beta-subunit mRNA was detected only at the late vitellogenic and migratory nucleus stages. These data indicate that eel GTH II is synthesized mainly at the late vitellogenic and migratory nucleus stages, and suggest that GTH II plays an important role in final oocyte maturation of Japanese eel. Changes in the expression of glycoprotein hormone alpha- and GTH II beta-subunits mRNA correlate with the serum estradiol-17 beta (E(2)) and testosterone profile during ovarian development. The increase in mRNA of both subunits is probably due to positive feedback of E(2) and testosterone produced by ovarian follicles in response to the GTH contained in chum salmon pituitary homogenate.

Amino Acid Sequence↗
PubMed1996

Localization of Na+, K(+)-ATPase in tissues of rabbit and teleosts using an antiserum directed against a partial sequence of the alpha-subunit.

A specific polyclonal antibody against Na+, K(+)-ATPase alpha-subunit was developed using a synthetic oligopeptide as antigen. By Western blot analysis under non-reducing conditions, this antibody recognized a protein band of approximately 150 kDa corresponding to the intact form (alpha beta-complex) of Na+, K(+)-ATPase in rabbit kidney. Furthermore, this antibody recognized a 150 kDa protein band corresponding to the intact form of Na+, K(+)-ATPase and some bands of about 60-65 kDa corresponding to fragments of the alpha-subunit in gill and kidney of masu salmon. This antibody did not recognize the alpha-subunit under reducing conditions. By immunohistochemical analysis, cells immunoreactive with this antibody were observed in renal tubular epithelial cells in kidney sections of rabbit, masu salmon, eel and rockfish. In addition, large spherical eosinophilic cells in gills of masu salmon, eel and rockfish were immunoreactive with the antibody. It is likely that these immunoreactive cells correspond to gill chloride cells. These data indicate that this antibody is a useful tool for studying changes in and the function of Na+, K(+)-ATPase during osmoregulatory adaptation in a variety of fish species.

Amino Acid Sequence↗
PubMed1996

[A study on the maternal plasma C21 steroids concentration during pregnancy].

During pregnancy, C21 steroids such as progesterone (P4), and cortisol (F), have been reported to be closely involved in uterine contraction. To clarify the association between changes in steroid hormones and the onset of delivery, we measured the concentrations of six C21 steroids in maternal blood by high performance liquid chromatography. Changes in each steroid hormone were evaluated by analysis of variance during pregnancy. Pregnenolone, a source of C21 steroids, gradually increased during pregnancy. P4 and 17P4, its metabolite, reached a peak 3 weeks before delivery and noticeably decreased thereafter. Accompanying a decrease in P4 and 17P4, 20P4 and F, its metabolite, were noticeably increased. The association among these steroid hormones was also evaluated. The correlation between P4 and F was reversed after 3 weeks before delivery. These results suggest that steroid hormones in the maternal blood begin to change dynamically about 3 weeks before delivery. In particular, a decrease in P4 and an increase in F seem to be closely related to the onset of delivery.

17-alpha-Hydroxyprogesterone↗
PubMed1996

[Utility of predeposit autologous blood donation by switch back method combined with recombinant human erythropoietin in gynecological surgery].

To apply recombinant human (rh)erythropoietin (EPO) to predeposit autologous blood donation (P.A.B.D.) in cancer patients clinically, (1) we tested the effects of rh-EPO on 2 ovarian cancer cell lines in vitro at first, then, (2) studied the effect of the rh-EPO for switch back (SB) method that is a variant of P.A.B.D. clinically. Rh-EPO (0.068-68U/ml) caused no significant and reproducible stimulation of clonal growth to SHIN-3 (derived from serous cyst adenocarcinoma) and MN-1 (derived from mucinous cyst adenocarcinoma). Twenty-five cases were studied. The change in the hemoglobin concentration (delta Hb) was -0.43 +/- 1.38g/dl (mean +/- SD) and the change in the total amount of hemoglobin (total delta Hb) which is calculated on the basis of whole blood volume was 111.5 +/- 53.2g/body in 16 cases with rh-EPO. The delta Hb and total delta Hb were -3.25 +/- 0.78g/dl and 30.1 +/- 41.7g/body in 9 cases without rh-EPO. The rh-EPO combined cases were significantly increased in both delta Hb and total delta Hb (p < 0.05, unpaired student t test). We therefore conclude that it would be very beneficial to use rh-EPO combined with the SB method in P.A.B.D. for high maximum surgical blood order schedule (MSBOS) cases such as gynecological malignancies.

Adult↗
PubMed1996

[Effect of timing of granulocyte-colony stimulating factor administration on leukopenia induced by systemic chemotherapy in patients with non-small-cell lung cancer--multi-center randomized crossover study].

Sixty-six chemotherapy-naive patients with non-small-cell carcinoma of the lung were given two courses of systemic chemotherapy consisting of mitomycin C, vindesine, and cisplatin. The effect of the timing of administration of grannulocyte colony-stimulating factor (G-CSF) on the incidence of neutropenic fever, the nadir leukocyte count, the duration of neutropenia ( < or = 1000/mm3), and the time needed for recovery from neutropenia was studied. Patients were assigned at random to begin receiving G-CSF (50 microns/m2, subcutaneously) either when the leukocyte count was less than or equal to 1000/mm3 (group I) or when it was between 1000/mm3 and 2000/mm3 (group II), in a crossover fashion. The nadir leukocyte count was lower in group I than in group II (859/mm3 and 1215/mm3, respectively). The duration of leukopenia (defined as a leukocyte count less than or equal to 1000/mm3) was greater in group I than in group II (1.5 days and 0.8 day, respectively), as was the time needed for recovery to a leukocyte count of 2000/mm3 (1.9 days and 1.6 days, respectively) (p < 0.05). No differences were found in the incidence of neutropenic fever (group I: 44%, group Ii: 45%), in the duration of fever (group I: 2.3 days, group II: 2.8 days), or in the duration of G-CSF use (group I: 6.3 days, group II: 6.8 days). There were no treatment-related deaths in either group. We conclude that when this type of combination chemotherapy is given for non-small-cell carcinoma of the lung, administration of G-CSF can be postponed without clinical problems until the leukocyte count is less than of equal to 1000/mm3.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1995

Iron-ligand structure and iron redox property of nitric oxide reductase cytochrome P450nor from Fusarium oxysporum: relevance to its NO reduction activity.

We studied the nitric oxide reductase, cytochrome P450nor, purified from a denitrifying fungus Fusarium oxysporum with electron paramagnetic resonance spectral and redox potential measurements. The EPR spectral features of P450nor in the ferric resting, the ferric cyanide-bound, and the ferrous NO-bound forms were the same as the corresponding ones of other general P450s such as Pseudomonas putida P450cam. In contrast, the metyrapone complex of ferric P450nor gave an EPR spectrum with significantly different g values from that of P450cam. The EPR results were explained in terms of similarity in the immediate configuration of the S(-)-Fe-ligand (H2O, CN-, NO) structure between P450nor and P450cam but a structural difference at the heme distal pocket, especially in the substrate binding domain; P450cam has a camphor binding domain, while P450nor does not. In spite of the same S(-)-Fe-H2O configuration, the redox potential of P450nor in the ferric/ferrous couple was measured to be -307 mV, which is much lower than those of the camphor-bound (-140 mV) and -free (-250 mV) P450cam. The lower redox potential could be attributable to the different electrostatic interaction of the heme with its surroundings; e.g., the heme environment of P450nor is charged either more negatively or less positively than P450cam.(ABSTRACT TRUNCATED AT 250 WORDS)

Binding Sites↗