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K Nishimura

Publications and source records attributed to K Nishimura.

At least 145 records · Page 8Linked to original sources
PubMed1990

[Changes in the immune response in postoperative patients while running the ventricular assist device (VAD)].

We examined the immunological parameters in two patients who were assisted with LVAD in postoperative LOS. Both patients demonstrated transient consumption of complements immediately after running the LVAD. The serum concentrations of immunoglobulins (IgG, IgM, IgA) showed no significant decrease. Both patients had significant postoperative lymphopenia, but recovered in a week. A decrease in the number of T cells was observed in both patients. The OKT4/OKT8 ratio initially increased in one patient, but gradually declined postoperatively. In the other patient, the OKT4/OKT8 ratio decreased. The lymphocyte response to mitogen (PHA) remained significantly depressed when the number of lymphocytes returned to the normal level, suggesting that the lymphocytes were functionally impaired. Such findings are generally observed after cardiac surgery. Thus, LVAD does not affect the immune response.

Adolescent↗
PubMed1990

Effect of chitin heparinoids on the activation of peritoneal macrophages and on the production of monokines in mice.

Sulfonated derivatives of chitin which showed anticoagulant activity (chitin heparinoids) were studied with regard to the activation of mouse peritoneal macrophages and the production of monokines. In comparison with 70% deacetylated chitin (DAC-70), which was the most adjuvant-active derivative of chitin, all chitin heparinoids were less effective for the augmentation of cytolytic activity of peritoneal macrophages. The number of macrophages was hardly increased or decreased by intraperitoneal injection of chitin heparinoids, and the activity of circulating colony-stimulating factor was not changed by their treatment. Only N-sulfonated DAC-70 stimulated the production of interleukin-1 by thioglycolate-induced peritoneal macrophages in vitro. However, its effect was weaker than that of DAC-70. Chitin heparinoids showed no or weak mitogenic activity on normal mouse spleen cells.

Adjuvants, Immunologic↗
PubMed1990

[Clinical experience with ceftibuten in complicated urinary tract infections].

Twenty-four patients with complicated urinary tract infections (UTI) were received ceftibuten (CETB) 400 mg b.i.d. orally for 5 days, and the following results were obtained. One of the recipients was excluded for negative bacteriuria before treatment. According to the criteria for evaluation of clinical efficacy of antimicrobial agents on UTI, 23 patients were assessed: 9 of them were judged to show excellent responses, 6 to have moderate responses and 8 poor responses. The overall efficacy was 65%. Four patients with indwelling catheter failed to show positive clinical response, but 15 out of 19 patients without indwelling catheter responded positively. As to bacteriological responses, organisms included Gram-positive cocci were eradicated in 28, replaced in 9 and persisted in 6 strains. Of 24 Gram-negative rods except 1 strain of Pseudomonas sp., 23 (96%) were eradicated. Safety evaluation was made in all 24 patients received CETB. No adverse reactions were observed in any cases. As to laboratory test results, slight, transient elevations of GOT, GPT and Al-P of serum were noted in 1 patient. Their values, however, returned to normal levels in 4 weeks.

Adult↗
PubMed1989

Assessment of transesophageal Doppler echography in dissecting aortic aneurysm.

To assess the clinical value of transesophageal Doppler echography in the diagnosis of dissecting aortic aneurysm, both transesophageal and conventional echograms were performed in 22 cases of dissecting aortic aneurysm. Of the 22 patients, 17 underwent angiography; 8, X-ray computed tomography; 4, both; and 12, surgery. The performance of each method was assessed in the following four segments: A, ascending aorta; B, aortic arch; C, thoracic descending aorta; and D, upper abdominal aorta. The results by angiography were presumed to be correct. In the group of 17 patients who underwent angiography, the rate of correct detection of an intimal flap using the transesophageal approach was 100% in all four segments, significantly better than detection by the conventional approach (segment A, 65%; segment B, 47%; segment C, 35%; segment D, 53%) (p less than 0.01), and the rate of correct detection of the entry sites using the transesophageal approach was 100%, significantly better than that by conventional approach (42%) (p less than 0.05). X-ray computed tomography was not capable of detecting the site of entry in all cases. The presence of thrombus, aortic regurgitation and pericardial hemorrhage were all revealed clearly by the transesophageal approach, and the results were partly proved by other methods. In conclusion, transesophageal Doppler echography provides a rapid and accurate method of diagnosing and evaluating dissecting aortic aneurysm and permits prompt initiation of appropriate treatment.

Adult↗
PubMed1989

Effects of D-serine on bacterial D-amino acid transaminase: accumulation of an intermediate and inactivation of the enzyme.

Incubation of pure bacterial D-amino acid transaminase with D-serine or erythro-beta-hydroxy-DL-aspartic acid, which are relatively poor substrates, leads to generation of a new absorbance band at 493 nm that is probably the quinonoid intermediate. The 420-nm absorbance band (due to the pyridoxal phosphate coenzyme) decreases, and the 338-nm absorbance band (due to the pyridoxamine phosphate or some other form of the coenzyme) increases. A negative Cotton effect at 493 nm in the circular dichroism spectra is also generated. Closely related D amino acids do not lead to generation of this new absorption band, which has a half-life of the order of several hours. Treatment of the enzyme with the good substrate D-alanine leads to a small but detectable amount of the same absorbance band. D-Serine but not erythro-beta-hydroxyaspartate leads to inactivation of D-amino acid transaminase, and D-alanine affords partial protection. The results indicate that D-serine is a unique type of inhibitor in which the initial steps of the half-reaction of transamination are so slow that a quinonoid intermediate with a 493-nm absorption band accumulates. A derivative formed from this intermediate inactivates the enzyme.

Circular Dichroism↗
PubMed1989

Stereospecificity of reactions catalyzed by bacterial D-amino acid transaminase.

The spectral shift from 420 to 338 nm when pure bacterial D-amino acid transaminase binds D-amino acid substrates is also exhibited in part by high concentrations of L-amino acids (L-alanine and L-glutamate) but not by simple dicarboxylic acids or monoamines. Slow processing of L-alanine to D-alanine was observed both by coupled enzymatic assays using D-amino acid oxidase and by high pressure liquid chromatography analysis employing an optically active chromophore (Marfey's reagent). When the acceptor for L-alanine was alpha-ketoglutarate, D-glutamate was also formed. This minor activity of the transaminase involved both homologous (L-alanine and D-alanine) and heterologous (L-alanine and D-glutamate) substrate pairs and was a function of the nature of the keto acid acceptor. In the presence of alpha-ketoisovalerate, DL-alanine was almost completely processed to D-valine; within the limits of the assay no L-valine was detected. With alpha-ketoisocaproate, 90% of the DL-alanine was converted to D-leucine. In the mechanism of this transaminase reaction, there may be more stereoselective constraints for the protonation of the quinonoid intermediate during the second half-reaction of the transamination reaction, i.e. the donation of the amino group from the pyridoxamine 5'-phosphate coenzyme to a second keto acid acceptor, than during removal of the alpha proton in the initial steps of the reaction pathway. Thus, with this D-amino acid transaminase, the discrete steps of transamination ensure fidelity of the stereospecificity of reaction pathway.

Bacillus↗
PubMed1989

High-performance liquid chromatography of proteins on N-methylpyridinium polymer columns.

Two types of 4-methylpyridinium polymers (4VP-DVB-Me and 4VP-EG-Me, cross-linked with divinylbenzene and ethylene glycol dimethacrylate, respectively) were employed for the analysis of proteins in ion-exchange high-performance liquid chromatography. These polymers had different physical properties in the dry state, but showed similar retentions in size-exclusion chromatography using carbohydrate standards. Generally, the 4VP-EG-Me column was superior to the 4VP-DVB-Me column with regard to separation and recovery of proteins.

Chromatography, High Pressure Liquid↗
PubMed1989

Activity and spectroscopic properties of bacterial D-amino acid transaminase after multiple site-directed mutagenesis of a single tryptophan residue.

One of the three tryptophan residues per subunit of thermostable D-amino acid transaminase, Trp-139, is close to the active-site Lys-145 in the sequence of the protein. This tryptophan has been changed to several other types of residues by site-directed mutagenesis. The only mutant protein that was sufficiently active and stable for study had Phe substituted for Trp (W139F). The spectroscopic properties of this mutant enzyme differed from those of the wild-type transaminase. For example, denatured W139F showed the expected decrease in fluorescence emission intensity at 350 nm due to the deletion of one Trp residue, but the fluorescence emission of the wild-type and W139F enzymes in the native state did not differ in intensity. This result suggests that the fluorescence of Trp-139 in the native, wild-type enzyme is not manifested perhaps due to its proximity to the coenzyme, pyridoxal phosphate. Results of energy-transfer studies at several wavelengths could also be interpreted as due to the proximity of Trp-139 and the coenzyme. Circular dichroism studies indicated that the negative Cotton effect at 420 nm due to the coenzyme was still present in W139F. However, the 280-nm optically active band present in the wild-type enzyme was greatly diminished in W139F. The mutant protein with Asp at position 139 (W139D) could not be isolated presumably because it was degraded. The other mutant enzymes, W139P, W139A, and W139H, were isolated with partial activities (15-35%) that were slowly lost upon storage at 4 degrees C. Overall, these results indicate the importance of Trp-139 in the thermostable D-amino acid transaminase.

Bacillus↗
PubMed1989

Identification of puberty-accelerating pheromones in male mouse urine.

Gas chromatography-mass spectrometry was employed to identify the two volatile amines in male mouse urine. These amines were much less concentrated in urine of castrated males. The identified amines, isobutylamine and isoamylamine, were assayed for the potential of puberty acceleration in postweaning female mice. A total of 105 young female mice were exposed to one of the following five odors: distilled water (control), 0.1 M isobutylamine, 0.1 M isoamylamine, a mixture of 0.05 M isobutylamine and 0.05 M isoamylamine, or fresh male mouse urine. The mixture of these amines accelerated the vaginal opening of young females. Except for the control, all experimental odors accelerated the first vaginal estrus in ICR strain mice.

Amines↗
PubMed1989

Scirrhous carcinoma of the stomach: a clinical and pathological study of 106 surgical cases.

Clinical and pathological characteristics of scirrhous carcinoma of the stomach were studied in 106 cases treated by gastrectomy between 1973 and 1983. The male to female ratio was 0.58. The percentage of scirrhous carcinomas to all gastric carcinomas resected in the same period was three times higher in females than males. The age distribution of the patients suggested that there were two peaks in the forties and sixties in the male, and in the thirties and fifties in the female. The incidence of scirrhous carcinoma in all types of gastric carcinoma was significantly higher in the twenties, thirties and forties compared to the lowest incidence in the seventies. In the female group the primary lesion had a tendency to be adjacent to the fundic gland area and to avoid intestinal metaplasia. In the male the opposite was recognized. Cancer nests with single cells or only several cells were common in this type of carcinoma. These findings suggest that there might be two biologically different scirrhous carcinomas both in the male and the female, the appearance of single carcinoma cells might be favored by female sex hormones and young ages, and not only the original gastric mucosa but also mucosa with intestinal metaplasia could be precursors of single carcinoma cells.

Adenocarcinoma, Scirrhous↗
PubMed1989

Separation and determination of theophylline from paraxanthine in human serum by reversed-phase high-performance liquid chromatography.

A sensitive and highly specific method for the determination of theophylline in serum by high-performance liquid chromatography (HPLC) has been developed. Theophylline was completely separated from paraxanthine, a major metabolite of caffeine which has been known to interfere with most isocratic reversed-phase HPLC methods, with a mixture of acetonitrile/tetrahydrofuran/acetate buffer (10 mM, pH 5.0; 5:1:94, v/v %) as the mobile phase using a C18 bonded reversed-phase column. Neither the other xanthine and uric acid derivatives nor numerous drugs tested were found to interfere. The proposed method was applied to therapeutic monitoring utilizing its excellent precision, reproducibility and high specificity for theophylline.

Aged↗
PubMed1989

Total replacement of the suprarenal inferior vena cava with an expanded polytetrafluoroethylene tube graft in 2 patients with tumor thrombi from renal cell carcinoma.

Total replacement of the suprarenal inferior vena cava using an expanded polytetrafluoroethylene vascular graft was successful in 2 renal cell carcinoma patients with extended tumor thrombi densely adherent to the vena caval wall. Right radical nephrectomy in 1 patient and enucleation of the tumor in the solitary right kidney were performed concomitantly. Both patients are well without tumor recurrence and with good vena caval patency 14 and 6 months postoperatively. This procedure could be a safer mode of operation in cases of extended vena caval involvement by malignant tumors. Total reconstruction of the inferior vena cava enables more radical resection of the tumor.

Blood Vessel Prosthesis↗
PubMed1989

Immunoadjuvant effects of periodontitis-associated bacteria.

Sonic extract (SE) from periodontopathic bacteria were studied for their effects on the immune response and adjuvanticity. The preparations of SE from A. actinomycetemcomitans, B. intermedius and B. gingivalis were found to have strong immunomodulating activity against the antigen itself and also sheep erythrocytes (SRBC) in in vivo experiments using C3H/HeN mice. All the SE enhanced the immune response to antigen and SRBC at low concentration. A strong immuno suppressive effect, however, was found at high concentrations of A. actinomycetemcomitans and B. intermedius but not of B. gingivalis. Moreover, these immunosuppressive effects were enhanced by the 3-day-prior injection to SRBC even at low concentrations, including that of B. gingivalis. The suppressive effect of SE from A. actinomycetemcomitans was dependent on the protein fraction in the SE tested, because suppressed anti-SRBC immune response was restored by pronase treatment or heating. Failure to recover immune response, found in a similar experiment using Bacteroides intermedius, indicated that its suppressive effect was due to a heat-stable and pronase-resistant substance. These findings, along with the data presented in this paper, support the hypothesis that patients who harbor these bacteria could suffer systemic immune suppression not only from the initial periodontopathic bacteria but also from secondary infecting bacteria. These suppressive effects may also enhance the pathogenicity of other opportunistic organisms in the gingival crevice.

Actinomyces↗
PubMed1989

[Effect of antibiotics and anti-cancer drugs on gastrointestinal infections and dissemination by C. albicans in mice inoculated orally with C. albicans].

The authors studied the effect of antibiotics, hydrocortisone and anti-cancer drugs on gastrointestinal infections and dissemination by C. albicans in mice inoculated orally with C. albicans. The mice were given orally, vancomycin, amikacin and polymyxin B, and they also were injected with ampicillin and gentamicin. Hydrocortisone, cyclophosphamide (CPA) which causes leukopenia and neutropenia, and methotrexate (MTX) which injures the mucous membrane of the gastrointestinal tract were injected to the mice. In the mice treated with antibiotics and anti-cancer drugs, and inoculated orally with C. albicans, the colony forming units of the feces conspicuously increased. Gastrointestinal candidiasis was frequently observed, particularly at the cardia and the cardio-antrum line of the stomach of these mice. In addition to these sites, gastrointestinal candidiasis was observed at the antrum and the small intestine of the mice injected with MTX. C. albicans was frequently recovered from the livers and lungs of the mice treated with antibiotics and MTX + CPA which cause leukopenia, neutropenia and the damage of mucous membrane of the gastrointestinal tract. It is suggested that the threshold gut population of C. albicans is a determinant for gastrointestinal candidiasis, and that leukopenia, neutropenia and the damage of mucous membrane of the gastrointestinal tract are important factors for dissemination by C. albicans from the primary gastrointestinal lesions.

Administration, Oral↗
PubMed1989

Cranial bone marrow in children: assessment of normal development with MR imaging.

Magnetic resonance images of cranial bone marrow in 238 patients (246 examinations) less than 25 years old were reviewed to establish normal age-related standards. Bone marrow in the clivus and calvaria had uniformly low signal intensity (grade 1) on T1-weighted images in most infants less than 1 year old. The number of patients with grade 1 marrow decreased rapidly in early childhood, while the number of patients with marrow of low and high signal intensity (grade 2) and uniformly high signal intensity (grade 3) gradually increased with age. A grade 1 marrow was no longer observed in either the clivus or calvaria after age 7. Most patients had a grade 3 marrow by age 15. Because bone marrow in certain pathologic conditions has decreased signal on T1-weighted images and therefore resembles grade 1 or 2 appearances of normal marrow in children, these results may be useful for differentiating normal and abnormal bone marrow signal intensities in infants and children.

Adult↗
PubMed1989

Carcinoma of the cervix: staging with MR imaging.

Demonstration and staging of carcinoma of the cervix with magnetic resonance (MR) imaging was evaluated prospectively in 67 patients with histologically proven lesions. Findings were correlated with surgical/pathologic results obtained within 2 weeks. MR imaging had an accuracy of 95% in demonstrating invasive disease (stage IB or higher). It was capable of depicting the location and extent of tumor invasion of cervical stroma and helped detect tumor beneath relatively normal epithelium or within the endocervical canal that had not been detected by means of colposcopic biopsy. The overall accuracy of MR imaging in staging carcinoma of the cervix was 76%, and in demonstrating parametrial status, the overall accuracy was 89%. In 39 patients with proven invasive disease, the accuracy in demonstrating parametrial status was 82%. In 13 of these 39 patients the low-signal-intensity stromal ring of the cervix on MR images was completely preserved and there were no false-positive results. MR imaging is a highly promising method for directly demonstrating and staging carcinoma of the cervix and seems to be capable of providing answers to crucial questions regarding mode of therapy.

Adult↗
PubMed1989

Enlarged uterus: differentiation between adenomyosis and leiomyoma with MR imaging.

The potential of magnetic resonance (MR) imaging in differentiation of adenomyosis from leiomyoma was evaluated in 93 patients who had a palpable enlarged uterus that was suspect for leiomyoma or adenomyosis. In all cases, MR images were correlated with surgical/pathologic findings. Pathologic findings showed that 71 enlarged uteri were due to leiomyoma, including one leiomyosarcoma, and 16 were due to adenomyosis. The other six patients were shown to have an enlarged uterus attributable to simultaneous involvement of both lesions. On T2-weighted images, adenomyosis appeared as an ill-defined, relatively homogeneous low-signal-intensity area embedded with sparse high-intensity spots. In contrast, leiomyomas were well-circumscribed masses with a spectrum of signal intensity. The cause of uterine enlargement was correctly diagnosed with MR images in 92 of the 93 cases. It is concluded that MR imaging is highly accurate in helping to distinguish between adenomyosis and leiomyoma in cases of enlarged uterus.

Adult↗