PubMed Health⌕ Search

Biomedical subjects

K Nishimura

Publications and source records attributed to K Nishimura.

At least 235 records · Page 13Linked to original sources
PubMed2000

[Retrieval and cryopreservation of testicular sperm].

We reviewed 44 cases of non-obstructive azoospermia treated by testicular sperm extraction and intracytoplasmic sperm injection (ICSI) from July, 1997 to September 1999 at our institutes. Testicular sperm were retrieved from 32 patients (72.7%). ICSI was performed on 29 patients and the partners of 15 patients (46.9%) became pregnant. Out of 10 patients with histology of Sertoli-cell-only, we could retrieve sperm from 3 patients (30%). Testicular volume, Johnsen's score count (JSC), and FSH were significant parameters to predict the recovery of testicular sperm from the patients, but if only the patients with JSC less than 8, are analyzed, none of them was significant parameter. Chromosomal abnormality was not a significant parameter. The partner's age, motility of recovered sperm and testicular volume correlated with the fertilization rate. Chromosomal abnormality or the usage of cryopreserved sperm was not a significant parameter to predict fertilization.

Adult↗
PubMed2000

[A case of ruptured distal aortic arch aneurysm with bronchiolitis obliterans organizing pneumonia].

We report a case of histologically proved bronchiolitis obliterans organizing pneumonia (BOOP) associated with ruptured distal aortic arch aneurysm (DAAA) into the lung. A 63-years-old male with preoperative episode of hemosputum and hemoptysis was diagnosed DAAA. Preoperative computed tomographic scanning demonstrated that the aneurysm was surrounded with the structure of 2 layers of the enhanced high density external layer and the not enhanced low density internal layer. Combined resection of the left upper lobe and the aneurysm was performed safely because of marked adhesion between the lung and the aneurysm. Postoperative histological examination revealed that the perianeurysmal structure was due to BOOP.

Aneurysm, Ruptured↗
PubMed2000

[Desensitization therapy for antituberculous drugs].

We retrospectively evaluated the effectiveness of desensitization therapy for antituberculous drugs (Rifampicin and Isoniazid) in 28 cases (29 episodes) with adverse reactions to these drugs. Desensitization therapy for RFP was performed in 23 cases (24 episodes) with administration of a first dose of 1-150 mg and a final dose of 300-450 mg for 1-29 days. The success rate of this therapy was 79% (19 of 24 episodes). Desensitization therapy for INH was performed in 12 cases with administration of a first dose of 2.5-100 mg and a final dose of 200-400 mg for 3-25 days. The success rate of this therapy was 83% (10 of 12 cases). Based on a comparative study of cases between successful and unsuccessful desensitization to RFP and INH it was concluded that there were no significant differences with regard to allergic history, adverse effects and their periods of appearance, the first dose and final dose of administration and the interval of administration, starting periods of the desensitization therapy and the periods of appearance of adverse effects due to this therapy. We evaluated desensitization therapy for two antituberculous drugs (RFP and INH) for tuberculous patients for whom the use of such drugs was restricted because of adverse effects, and we found it is a useful treatment, showing a high rate of success (80%).

Adolescent↗
PubMed2000

[Desensitization therapy for allergic reactions of antituberculous drugs--evaluation of desensitization therapy according to the guideline of the Japanese Society for Tuberculosis].

We prospectively evaluated the effectiveness of desensitization therapy for cases showing side-effects to antituberculous drugs (Isoniazid and Rifampicin) according to the guideline proposed by the Treatment Committee of the Japanese Society for Tuberculosis. Nineteen patients (23-88 years old, male 9, female 10) who had experienced adverse effects after receiving antituberculous drugs and underwent desensitization therapy between August 1998 and March 2000 were studied. Underlying diseases were 14 cases of pulmonary tuberculosis, 2 cases of cervical tuberculous lymphadenitis, 1 case of pulmonary atypical mycobacteriosis, 1 case of pulmonary tuberculosis and tuberculous pleuritis, 1 case of pulmonary tuberculosis and tuberculous lymphadenitis. The regimens of treatment for tuberculosis were INH + RFP + EB in 8 cases, INH + RFP + EB + PZA in 7 cases, INH + RFP + SM in 2 cases, INH + RFP + SM + PZA in 1 case, and INH + RFP in 1 case. Adverse reactions were 8 cases of eruption, 7 cases of drug fever, 3 cases of drug fever and eruption, and 1 case of drug fever and cervical lymphadenopathy. The causative drugs suggested from DLST or the clinical course were RFP in 17 cases and INH in 8 cases. The clinical effect of desensitization therapy for these antituberculous drugs was good in 14 out of the 17 cases (82%) for RFP, and in 6 out of 8 cases (75%) for INH. The effectiveness rate of the present desensitization therapy according to the guideline of the Japanese Society for Tuberculosis was almost equal to that of previous desensitization therapy, and the clinical results were almost same in present and previous studies despite the different methods of administration of the antituberculous drugs.

Adult↗
PubMed2000

[Clinical evaluation of urinary basic fetoprotein and the BTA test for detection of bladder cancer].

We compared the results of urinary basic fetoprotein (BFP) and the BTA test with those of urinary cytology in patients with bladder cancer. We also analyzed the urinary BFP and the BTA test results in patients with benign diseases and postoperative bladder cancer with no evidence of recurrence. The cutoff value for urinary BFP was set at 10 ng/ml. Classes 4 and 5 according to urinary cytology were defined as positive. The sensitivity of urinary BFP for Ta, 1 bladder cancer was significantly higher than that of urinary cytology (p < 0.05). The urinary cytology positive rate for Ta, 1 bladder cancer improved when combined with urinary BFP and the BTA test. The urinary BFP positive rate for benign diseases was significantly higher in patients with pyuria than in patients without pyuria (p < 0.05). The BTA test positive rate for benign diseases was higher in patients with pyuria than in patients without pyuria. The urinary BFP and the BTA test positive rates for postoperative bladder cancer with no evidence of recurrence was significantly higher in patients with urinary diversion than in patients without urinary diversion (BFP: p < 0.01, BTA: p < 0.05).

Adult↗
PubMed2000

[Metastatic bladder tumor disseminated lymphogenously from gastric cancer: a case report].

A 59-year-old man was referred to our clinic with a complaint of frequent urination, voiding pain, and macroscopic hematuria. He had undergone total gastrectomy for mucinous adenocarcinoma, 21 months earlier. Pelvic computed tomography revealed a thick bladder wall all around. There were no other metastatic sites except for paraaortic lymph nodes. Transurethral resection of the bladder tumor was performed. The specimen showed signet ring cell carcinoma and revealed the same pathological findings as the primary gastric cancer. We diagnosed him with metastastic bladder tumor lymphogenously disseminated from gastric cancer. Such lymphogenous metastases from gastric cancer at the entire bladder wall without other apparent lesions have rarely been reported in the Japanese literature.

Adenocarcinoma, Mucinous↗
PubMed2000

[Role of hepatocyte growth factor in invasion of prostate cancer cell lines through tumor-stromal interaction].

We examined how prostate stromal cell-derived hepatocyte growth factor (HGF) affects invasion of prostate cancer cells through tumor-stromal interaction. The effects of HGF, various growth factors [transforming growth factor (TGF)-alpha, TGF-beta 1, basic fibroblast growth factor, keratinocyte growth factor, and platelet-derived growth factor], and conditioned medium (CM) from prostate stromal cells (PrSC) on prostate cancer cells (LNCaP, PC-3 and DU145) were determined by collagen gel invesion assay. DU145 cells and PrSC were co-cultured for matrigel invasion chamber assay. LNCaP and PC-3 cells did not respond to any of the factors examined. Invasion of DU145 cells into the collagen gel matrix was induced by HGF and TGF-beta 1, but not by any of the other factors tested. When DU145 cells were cultured in CM from PrSC or co-cultured with PrSC, the cells acquired invasive potential, and this invasion was inhibited by an antibody against HGF, but not against TGF-beta 1. Induction activity of CM from cancer cells to stimulate HGF production by PrSC was studied by ELISA method and Western blotting. Native type HGF production in PrSC was enhanced by some unknown inducer(s) produced by cancer cells. In summary, PrSC-derived HGF enhanced invasive activity of the prostate cancer cell line DU145 through tumor-stromal interaction wherein DU145 cells secreted some HGF-inducer(s) for PrSC.

Cell Communication↗
PubMed1999

K(+) channel blockers and cytochrome P450 inhibitors on acetylcholine-induced, endothelium-dependent relaxation in rabbit mesenteric artery.

Acetylcholine caused an endothelium-dependent relaxation in isolated rabbit mesenteric small artery in the presence of nitro L-arginine and indomethacin. The acetylcholine-induced relaxation was attenuated by high K(+) solution, suggesting that the response is mediated by a membrane potential-sensitive mechanism, presumably an endothelium-derived hyperpolarizing factor. The acetylcholine-induced relaxation was also inhibited with tetraethylammonium, 4-aminopyridine and charybdotoxin, but not with Ba(2+), apamin, iberiotoxin nor glibenclamide. The relaxation was abolished by a combination of apamin and charybdotoxin, but iberiotoxin could not replace charybdotoxin in this combination. The responses to charybdotoxin and 4-aminopyridine were synergistic but neither apamin nor iberiotoxin increased the effect of 4-aminopyridine. Clotrimazole and proadifen inhibited the acetylcholine-induced relaxation, but these drugs also inhibited the cromakalim-induced relaxation, while protoporphyrin IX inhibited the acetylcholine- but not cromakalim-induced relaxation. 17-Octadecynoic acid and 1-aminobenzotriazole did not affect the response to acetylcholine. Four regioisomers of epoxyeicosatrienoic acids did not relax endothelium-denuded artery. A gap junction inhibitor 18alpha-glycyrrhetinic acid attenuated the relaxation to acetylcholine. It is suggested that in rabbit mesenteric artery, the acetylcholine-induced, nitric oxide- and prostacyclin-independent relaxation is mainly mediated by 4-aminopyridine- and charybdotoxin-sensitive K(+) channels and that the relaxation is not mediated through cytochrome P450 enzyme metabolites. The contribution of heterocellular gap junctional communication to the relaxation is discussed.

8,11,14-Eicosatrienoic Acid↗
PubMed1999

Prostate stromal cell-derived hepatocyte growth factor induces invasion of prostate cancer cell line DU145 through tumor-stromal interaction.

BACKGROUND: In prostate cancer, several growth factors derived from stromal cells regulate tumor cell growth. Hepatocyte growth factor (HGF) possesses biological activities that promote cancer proliferation and invasion through tumor-stromal interaction. We examined how prostate stromal cell-derived HGF affects invasion of prostate cancer cells through this interaction. METHODS: The effects of HGF, various growth factors (transforming growth factor (TGF)-alpha, TGF-beta1, basic fibroblast growth factor, keratinocyte growth factor, and platelet-derived growth factor), and conditioned medium (CM) from prostate stromal cells (PrSC) on prostate cancer cells (LNCaP, PC-3, and DU145) were determined by collagen gel invasion assay. DU145 cells and PrSC were cocultured for Matrigel invasion chamber assay. Induction activity of CM from cancer cells to stimulate HGF production by PrSC was studied by the ELISA method and Western blotting. RESULTS: LNCaP and PC-3 cells did not respond to any of the factors examined. Invasion of DU145 cells into the collagen gel matrix was induced by HGF and TGF-beta1, but not by any of the other factors tested. When DU145 cells were cultured in CM from PrSC or cocultured with PrSC, the cells acquired invasive potential, and this invasion was inhibited by an antibody against HGF, but not against TGF-beta1. Native-type HGF production in PrSC was enhanced by some unknown inducer(s) produced by cancer cells. CONCLUSIONS: PrSC-derived HGF enhanced invasive activity of the prostate cancer cell line DU145 through tumor-stromal interaction, wherein DU145 cells secreted some HGF-inducer(s) for PrSC.

Cell Communication↗
PubMed1999

Gene structure and chromosomal localization of mouse S-adenosylmethionine decarboxylase.

The structure of the mouse S-adenosylmethionine decarboxylase (AdoMetDC) gene has been determined. The mouse gene (AMD1) consisted of eight exons and seven introns, similar to the rat AdoMetDC gene, and was mapped to chromosome 10. The characteristics of AMD1 gene were as follows: (1) The region of the promoter necessary for maximal transcriptional activity was located about 400 nucleotides upstream of the transcriptional initiation point, and contained a TATA box and two GC boxes. The transcriptional activity of the promoter was nearly equal to that of the SV40 promoter. (2) Two polyadenylation signals for transcription were observed, and the larger AdoMetDC mRNA, which is the dominant form of mRNA, corresponded to mRNA that is generated using the second polyadenylation signal. (3) Using stable transfectants, we confirmed that the upstream open reading frame (uORF) in the 5'-untranslated region (5'-UTR) of AdoMetDC mRNA functioned as a negative regulatory element. Lower concentrations of polyamines affect both stimulation and inhibition of AdoMetDC synthesis, through the uORF in the mRNA, than affect general protein synthesis.

5' Untranslated Regions↗
PubMed1999

Exploration of optimal giving-up time in uncertain environment: a sit-and-wait forager

I address variability of giving-up time of a sit-and-wait forager in a stochastic environment. Behavioral variability is considered as an essential unavoidable feature of animals. In a stochastic environment, this unavoidable behavioral variability will increase. Thus, the existence of some behavioral variation would be considered to be a constraint. I analyse the expected long-term reward rate for a model of patch exploitation by a sit-and-wait forager as a function of giving-up time (GUT) given environmental stochasticity and a base behavioral variability. While the animal is learning about the environment, a mixed strategy is favored and thus, more variability is added to behavior. I claim that it is important to study not only the final optimal strategy but also the strategy used during the exploration process. Copyright 1999 Academic Press.

Journal Article↗
PubMed1999

Complexity of terminal airspace geometry assessed by lung computed tomography in normal subjects and patients with chronic obstructive pulmonary disease.

Increases in the low attenuation areas (LAA) of chest x-ray computed tomography images in patients with chronic obstructive pulmonary disease (COPD) have been reported to reflect the development of pathological emphysema. We examined the statistical properties of LAA clusters in COPD patients and in healthy subjects. In COPD patients, the percentage of the lung field occupied by LAAs (LAA%) ranged from 2.6 to 67.6. In contrast, LAA% was always <30% in healthy subjects. The cumulative size distribution of the LAA clusters followed a power law characterized by an exponent D. We show that D is a measure of the complexity of the terminal airspace geometry. The COPD patients with normal LAA% had significantly smaller D values than the healthy subjects, and the D values did not correlate with pulmonary function tests except for the diffusing capacity of the lung. We interpret these results by using a large elastic spring network model and find that the neighboring smaller LAA clusters tend to coalesce and form larger clusters as the weak elastic fibers separating them break under tension. This process leaves LAA% unchanged whereas it decreases the number of small clusters and increases the number of large clusters, which results in a reduction in D similar to that observed in early emphysema patients. These findings suggest that D is a sensitive and powerful parameter for the detection of the terminal airspace enlargement that occurs in early emphysema.

Forced Expiratory Volume↗
PubMed1999

Involvement of Spt7p in vacuolar polyphosphate level of Saccharomyces cerevisiae.

Saccharomyces cerevisiae became less sensitive to nickel by a defect of the SPT7 gene encoding a transcription factor. Initial rate of nickel uptake by whole cells of a SPT7-negative mutant FY963 was nearly equal to that of the parent strain FY61, and FY963 accumulated nickel about 1.7-fold of the value of FY61 when cultured in medium containing 0.1 mM NiCl2; most of which was sequestered into vacuoles. The pH gradient-driven nickel uptake by vacuolar membrane vesicles was not altered in FY963, but the amount of polyphosphate in vacuoles was highly elevated. Involvement of Spt7p in nickel detoxification through regulation of vacuolar polyphosphate level in S. cerevisiae was discussed.

Biological Transport↗
PubMed1999

Assessment of regional and global left ventricular function by reinjection T1-201 and rest Tc-99m sestamibi ECG-gated SPECT: comparison with three-dimensional magnetic resonance imaging.

OBJECTIVES: The purpose of this study was to test the ability of reinjection thallium-201 and rest technetium-99m sestamibi ECG (electrocardiographic)-gated SPECT (i.e., reinjection-g-SPECT [single-photon emission computed tomography] and MIBI-g-SPECT) to determine regional and global functional parameters. BACKGROUND: The ECG-gated perfusion SPECT was reported to provide accurate left ventricular ejection fraction (LVEF) using an automated algorithm. We hypothesized that other various functional data may be obtained using reinjection-g-SPECT and MIBI-g-SPECT. METHODS: Reinjection-g-SPECT, MIBI-g-SPECT, and three-dimensional magnetic resonance imaging (3DMRI) were conducted in 20 patients with coronary artery disease. Regional wall motion (RWM) and wall thickening (RWT) were analyzed using semiquantitative visual scoring by each g-SPECT and 3DMRI. The left ventricular end-systolic and end-diastolic volumes (EDV, ESV) and LVEF estimated by reinjection- and MIBI-g-SPECT were compared with the results of 3DMRI. RESULTS: A high degree of agreement in RWM and RWT assessment was observed between each g-SPECT and 3DMRI (kappa >.70, p < .001). The LVEF values by reinjection- and MIBI-g-SPECT correlated and agreed well with those by 3DMRI (reinjection: r = .92, SEE = 5.9%, SD of differences = 5.7%; sestamibi: r = .94, SEE = 4.4%, SD of differences = 5.1%). The same also pertained to EDV (reinjection: r = .85, SEE = 18.7 ml, SD of differences = 18.4 ml; sestamibi: r = .92, SEE = 13.1 ml, SD of differences = 13.0 ml) and ESV (reinjection: r = .94, SEE = 10.3 ml, SD of differences = 10.3 ml; sestamibi: r = .97, SEE = 6.7 ml [p < .05 vs. reinjection by F test], SD of differences = 6.6 ml [p < .05 vs. reinjection by F test]). CONCLUSIONS: Reinjection- and MIBI-g-SPECT provide clinically satisfactory various functional data. These functional data in combination with the perfusion information will improve diagnostic and prognostic accuracy without an increase in cost or the radiation dose to the patients.

Adult↗
PubMed1999

Lack of effect of carbohydrate depletion on some properties of human mast cell chymase.

Human chymase from vascular tissues was purified to homogeneity by heparin affinity and gel filtration chromatography. Treatment of human chymase with endoglycosidase F resulted in cleavage of the carbohydrate moiety yielding a deglycosylation product that did not lose its catalytic activity. This enzymatic deglycosylation product was enough to explore possibilities that N-glycan might modify some properties of human chymase. Substrate specificity, optimum pH and the elution profile from the heparin affinity gel were not affected by the deglycosylation. Only a slight but significant difference was observed in the Km value for conversion of angiotensin I to angiotensin II. Other kinetic constants such as kcat were not influenced. The kinetics of conversion of big endothelin-1 to endothelin-1(1-31) were not significantly affected. The deglycosylated human chymase was more susceptible to deactivation under alkaline pH and thermal stress. Even at physiological temperature and pH, the activity of glycosylated human chymase was more stable. From these results, it appears that the N-glycan of human chymase contributes to the stability of this enzyme but not to its functional properties.

Carbohydrates↗
PubMed1999

Transcription of some PHO genes in Saccharomyces cerevisiae is regulated by spt7p.

Spt7p is a new global transcription factor in Saccharomyces cerevisiae(Gansheroff et al., 1995). We report here that the activities of high affinity phosphate transport and acid phosphatase in particular were decreased in a spt7 null mutant. Northern blot experiments revealed that transcription of the PHO84 and PHO5 genes was impaired in this mutant; expression of the PHO regulatory genes, PHO4 and PHO2, was normal. Spt7p is thus linked with expression of several structural genes of the PHO regulon in yeast.

Acid Phosphatase↗
PubMed1999

Chondroprogenitor cells of synovial tissue.

OBJECTIVE: To assess the chondrogenic potential of cells within the synovium. METHODS: Explants of synovium taken from various sites in the joint were embedded in agarose and cultured with transforming growth factor beta1 (TGFbeta1) to assess their chondrogenic potential. Isolated synovial cells were also tested for their chondrogenic potential by culturing them as aggregates in a chemically defined medium with TGFbeta1. Cartilage formation was determined with histologic staining and immunohistochemistry. The osteochondral potential of the isolated cells was also assessed after subcutaneous implantation of the cells, loaded into porous calcium phosphate ceramic cubes, in athymic mice. RESULTS: A total of 48 synovial explants were cultured in agarose with TGFbeta1. The formation of cartilage was observed in the outer region of 21 explants, and type II collagen was localized in that region by immunohistochemistry. A larger percentage of TGFbeta1+ explants from the inner synovium sites formed cartilage compared with those from the outer synovium sites. Chondrogenesis occurred in aggregates incubated with TGFbeta1 as early as day 7, and by day 14, all TGFbeta1+ aggregates demonstrated chondrogenesis. In contrast with the results of the in vitro aggregate assay for chondrogenesis, no formation of cartilage or bone was evident in any section containing synovial cell-loaded ceramic cubes that were harvested at either 3 or 6 weeks after implantation subcutaneously in athymic mice. CONCLUSION: Synovial explants and isolated synovial cells will undergo chondrogenesis when cultured in the presence of TGFbeta1. The data indicate a possible synovial origin for the chondrocytic cells found in rheumatoid pannus. Furthermore, these data are consistent with the clinical findings of synovial chondrogenesis leading to synovial chondromatosis.

Animals↗