PubMed Health⌕ Search

Biomedical subjects

H Nishimura

Publications and source records attributed to H Nishimura.

At least 343 records · Page 19Linked to original sources

Comparable effects of angiotensin II and converting enzyme blockade on hemodynamics and cardiac hypertrophy in spontaneously hypertensive rats.

Angiotensin-converting enzyme inhibitors may regress left ventricular hypertrophy (LVH) without decreasing blood pressure (BP). The aim of the present study was to compare the effects of low and high doses of lisinopril and the angiotensin II receptor antagonist TCV116 (TCV) on LVH and hemodynamics in spontaneously hypertensive rats (SHR). Lisinopril (0.5 and 3 mg/kg per day) and TCV (0.3 mg/kg per day) were given to 8-week-old male SHR daily for 2 weeks. Untreated SHR and Wistar-Kyoto rats (WKY) served as controls. Untreated SHR had a greater left ventricular (LV) weight than WKY (p < 0.01). Lisinopril (3 mg/kg per day) decreased both LV weight and BP. Lisinopril (0.5 mg/kg per day) significantly decreased LV weight, but not BP. In contrast, although TCV significantly decreased BP, LVH was not suppressed. Renal blood flow (RBF) in untreated SHR was less than that in WKY (p < 0.05), but was increased with either lisinopril (3 mg/kg per day)-treated rats (p< 0.05). These findings suggest that factors other than afterload reduction play a role in the regression of LVH with lisinopril, whereas a longer duration of treatment and/or a higher dose may be necessary with TCV. Despite the decrease in BP, TCV normalized RBF in SHR, perhaps due to the blockade of renal angiotensin II.

Angiotensin II↗

Absolute configuration of a new mosquito repellent, (+)-eucamalol and the repellent activity of its epimer.

(+)-Eucamalol (1) and (-)-1-epi-eucamalol (2) were synthesized from (S)-(-)-perillaldehyde to determine the absolute configuration of 1, the structure of natural (+)-eucamalol being determined to be (1R,6R)-(+)-3-formyl-6-isopropyl-2-cyclohexen-1-ol. (+)-Eucamolol (1) and its 1-epimer (2) exhibited significant repellent activity against Aedes albopictus, and inhibited its feeding as well as DEET.

Aedes↗

A catechol 2,3-dioxygenase gene as a reporter.

A catechol 2,3-dioxygenase (C23O) gene of Pseudomonas aeruginosa was expressed under the Simian virus 40 or Rous sarcoma virus promoter in mammalian cells; it was found that the gene could be used as a reporter for the study of gene expression. The C23O gene was a more sensitive reporter than the generally used beta-galactosidase gene.

Amino Acid Sequence↗

[A case of myogenic intractable pain due to thalamic hemorrhage relieved by Vim-Vo thalamotomy].

A 58-year-old female patient with myogenic intractable pain due to thalamic hemorrhage which was relieved by stereotactic Vim-Vo thalamotomy was reported. She had an intractable pain, involuntary movement and deep sensory disturbance in her right arm. We performed stereotactic Vim-Vo thalamotomy using electrophysiological technique to relieve her involuntary movement and myogenic intractable pain. The electrophysiological recordings suggested the followings: (1) The destructive lesion by thalamic hemorrhage was located on from posterior border of Vim nucleus to the upper half of Vc nucleus. (2) Most of Vim neurons remained as intact state. (3) Thalamic electrical activities were relatively enhanced in the Vim nucleus. From these data, we can deduce that the deep sensory inputs reach the border area of Vim nucleus and Vc nucleus in the human thalamus. IMP-SPECT scans were performed before and after the operation. IMP-SPECT scan before operation showed us the contra-lateral cerebellar low perfusional state (crossed cerebellar diaschisis). This crossed cerebellar diaschisis disappeared after the operation. This result suggested that the interaction of cerebellum and Vim nucleus was very close. The above mentioned speculation was more compatible to Jones & Hirai's new parcellation of the human thalamus than to Hassler's.

Cerebral Hemorrhage↗

Effects of in vivo administration of anti-IL-10 monoclonal antibody on the host defence mechanism against murine Salmonella infection.

Interleukin-10 (IL-10) is a cytokine that regulates various macrophage functions. To elucidate the involvement of endogenous IL-10 in the early stage of murine salmonellosis, we examined the effect of anti-IL-10 monoclonal antibody (mAb) administration on the host defence mechanism against Salmonella choleraesuis infection. The in vivo administration of anti-IL-10 mAb significantly enhanced host resistance at the early stage of Salmonella infection, as assessed by bacterial growth in the peritoneal cavity and the liver. Enhanced levels of monokine mRNA, including IL-1 alpha, tumour necrosis factor-alpha (TNF-alpha) and IL-12, were observed from day 1 after infection in the peritoneal macrophages in anti-IL-10 mAb-treated mice compared with those in control mAb-treated mice. Mice treated with anti-IL-10 mAb exhibited significantly higher levels of interferon-gamma (IFN-gamma) in the peritoneal exudates and major histocompatibility complex (MHC) class II expression on the peritoneal macrophages on days 3 and 5 after infection. Notably, in vivo anti-IL-10 mAb brought about an increment of gamma delta T cells in the peritoneal cavity at the early phase of infection, which was correlated with the expression of endogenous heat-shock protein 60 (HSP60), which is implicated as a potential ligand for gamma delta T cells, in the infected macrophages. Our results suggest that the neutralization of endogenous IL-10 accelerates some macrophage functions and, consequently, the activation of immunocompetent cells, including gamma delta T cells, at the early stage of infection, resulting in an enhanced host defence against Salmonella infection.

Animals↗

[The relationship between genotypes of HLA-DRB1 alleles and progression of bony destruction changes of rheumatoid arthritis].

The relationship between genotypes of HLA-DRB 1 alleles and the progression of bone destruction of RA patients was assessed. The genotypes of the HLA-DRB 1 alleles were determined in 329 Japanese patients with seropositive RNA by polymerase chain reaction and allele-specific oligonucleotide probe techniques. We regarded HLA-DRB 1* 0101, 0401, 0404, 0405, 1001 and 1402 as susceptible alleles of RA and classified the patients into three groups. The s/s group consisted of those with susceptible factors in both of the HLA-DRB 1 alleles. The s/n group was made up of those having one susceptible factor and one non-susceptible factor. The n/n group consisted of those possessing two non-susceptible factors. The grading of radiographic change that was evaluated by Larsen's criteria compared with the genotyped results. In the result, the median years taken to development to grade III, IV and V were significantly shorter in the s/s groups compared with that in the s/n and n/n groups. Thus, genotyping of HLA-DRB 1 can be a useful prognostic market in the progression of bone destruction of RA.

Adult↗

[MR diagnosis for metastasis or non-metastasis of mediastinal and hilar lymph nodes in cases of primary lung cancer: detectability, signal intensity, and MR-pathologic correlation].

The detectability and signal intensity on MR imaging of mediastinal and hilar lymph nodes were studied in cases of lung cancer. Additionally, short inversion time inversion recovery (STIR) images and pathologic findings were compared. In the detection of resected metastatic mediastinal and hilar lymph nodes (n = 146), the STIR image (82%) was superior to the T1-weighted image (71%) and the T2-weighted image (60%). On STIR imaging, 212 (60%) of 412 resected non-metastatic mediastinal nodes and 38 (33%) of 116 resected non-metastatic hilar lymph nodes were detected. Characteristics of signal intensities of metastatic nodes were mainly low on T1-weighted images, high on T2-weighted images, and very high on STIR images. The rate of these characteristics of signal intensity of metastatic nodes was 59%. However, the rate of very high signal intensity of metastatic nodes on STIR imaging was 81%. Pathologically, lymph nodes with high or very high signal intensities on STIR images were metastatic, reactive and hyperplastic, or non-metastatic. Lymph nodes with slightly high signal intensity or high intensity with a low focus on STIR images were anthracotic, anthrasilicotic, caseous necrotic, calcified, or fibrotic. Thus, when the signal intensity of a lymph node was decreased on the STIR image, there was no definite evidence of metastasis excluding micro-metastasis or coagulation necrosis of a metastatic tumor. We conclude that the signal characteristics on STIR imaging are useful for distinguishing between macro-metastatic and non-metastatic lymph nodes when enlarged nodes are detected by various other types of medical imaging.

Adenocarcinoma↗

Management of chylothorax after pulmonary resection.

BACKGROUND: Conservative management with intrapleural drainage and total parenteral nutrition (TPN) has been the first choice of treatment for postoperative chylothorax. With this approach, however, it usually takes several weeks for the chylothorax to resolve and it is sometimes unsuccessful. In this study, we reviewed seven patients who had chylothorax develop after pulmonary resection for primary carcinoma of the lung. STUDY DESIGN: The patients were treated according to a "one-week trial" that consisted of one week of observation with intrapleural drainage and maximum parenteral nutritional support followed by operative intervention if the effect of the conservative therapy was not adequate. When the chylous leak was decreased to less than 100 mL/day or less than 15 percent of the maximum daily drainage volume after the "one-week trial," the conservative management was continued for two more weeks. After observation for three weeks, oral intake was begun and a final evaluation of the treatment was made. RESULTS: One patient did not consent to the "one-week trial" and underwent operative treatment on the third postoperative day. Two patients had chylous leaks less than 100 mL/day or less than 15 percent of the maximum daily chylous leak after one week observation. Conservative management with TPN was continued in these patients for two more weeks and operation was performed in one on the 20th day and in the other on the 22nd postoperative day. The remaining four patients underwent operative treatment on the seventh or eighth postoperative day. All of the operations for chylothorax were successful, and chest tubes were removed promptly. These results show that operative management of chylothorax was reliable and safe. The "one-week trial," however, offered few advantages in determining the therapeutic strategy for postoperative chylothorax.

Adult↗

[Troponin T].

Explore the source record for details and available documents.

Biomarkers↗

Isolation and characterization of the THI6 gene encoding a bifunctional thiamin-phosphate pyrophosphorylase/hydroxyethylthiazole kinase from Saccharomyces cerevisiae.

Thiamin-phosphate pyrophosphorylase (TMP-PPase; EC 2.5.1.3) involved in de novo synthesis of thiamin in Saccharomyces cerevisiae is a bifunctional enzyme with 4-methyl-5-beta-hydroxyethylthiazole kinase (Th-kinase; EC 2.7.1.50) activity, which is an octamer of identical 60-kDa subunits (Kawasaki, Y. (1993) J. Bacteriol. 175, 5153-5158). Previous study demonstrated that the activities of both TMP-PPase and Th-kinase are reduced by the mutation of a single nuclear gene, designated THI6. We have cloned the THI6 gene from a yeast genomic library by functional complementation of the thi6 mutant and determined by DNA blot analysis that THI6 is located on chromosome XVI. The nucleotide sequence of the THI6 gene contained an open reading frame of 1,620 base pairs encoding a 540-amino acid polypeptide with a calculated molecular weight of 58,058, which is similar to the determined molecular mass of the purified bifunctional enzyme. Gene disruption demonstrated that the thi6 null strain is auxotrophic for thiamin, indicating that the THI6 protein is essential for thiamin synthesis in yeast. A recently isolated thi6 mutant, thi6-3, bearing a replacement of Glu370 by Lys370, showed a decrease in only Th-kinase activity, proving that the THI6 gene of S. cerevisiae encodes a structural gene of the thiamin biosynthetic bifunctional enzyme. Furthermore, complementation analysis of the thi6 null strain with the modified THI6 DNAs by a 12-nucleotide linker insertion suggested that a region from amino acids 138 to 187 and that from amino acids 370 to 453 are involved in functional domains of TMP-PPase and Th-kinase, respectively, whereas the COOH-terminal region is necessary for both enzyme activities. Strains conferring no Th-kinase but slight TMP-PPase activity could grow in medium without thiamin, suggesting that 4-methyl-5-beta-hydroxyethylthiazole is not involved in the pathway of de novo synthesis of thiamin via 4-methyl-5-beta-hydroxyethylthiazole monophosphate. Northern blot analysis demonstrated that THI6 gene expression is regulated at the mRNA level by intracellular thiamin pyrophosphate, a coenzyme form of thiamin, and that it requires the positive regulatory factors encoded by the THI2 and THI3 genes.

Alkyl and Aryl Transferases↗

Purification and characterization of a novel substrate for plasma kallikrein (PK-120) in human plasma.

A 120 kDa plasma protein, which is susceptible to plasma kallikrein, was purified from human plasma by polyethylene glycol fractionation followed by ion exchange chromatography using Q-Sepharose, S-Sepharose, and hydroxyapatite and gel filtration on Sephacryl S-200. The 120 kDa protein, termed PK-120 in this paper, was a single polypeptide chain containing about 20% sugar by weight and its concentration in plasma was estimated to be 80 micrograms/ml by ELISA. At least three fragments, 100, 70, and 35 kDa, were produced from PK-120 by plasma kallikrein. The N-terminal sequence and Western blot demonstrated that PK-120 was first cleaved to yield the 100 and 35 kDa fragments, then the 100 kDa fragment was cleaved into the 70 kDa fragment. N-Terminal sequence analyses of PK-120 and its fragments demonstrated that it is a novel plasma protein, distinct from high molecular weight kininogen, a natural substrate for plasma kallikrein.

Amino Acid Sequence↗

Activation of the alternative pathway of complement by apoptotic Jurkat cells.

Jurkat T cells die of apoptosis upon exposure to anti-Fas mAb. Here we show that although the alternative complement pathway generally does not attack homologous cells, anti-Fas-induced apoptotic Jurkat T cells were attacked antibody-independently by the alternative pathway of human complement and opsonized with iC3b, which is a ligand of the complement receptor type 3 (CR3) of phagocytes. These results suggest that apoptotic cells become the targets of the homologous alternative complement pathway, which facilitates the clearance of apoptotic cells by phagocytes.

Antibodies, Monoclonal↗

Staurosporine inhibits phorbol 12-myristate 13-acetate- and insulin-stimulated translocation of GLUT1 and GLUT4 glucose transporters in rat adipose cells.

Staurosporine, a widely used protein kinase C inhibitor, completely inhibited both phorbol 12-myristate 13-acetate (PMA)- and insulin-stimulated glucose transport activity in isolated rat adipocytes. The inhibition was non-competitive and was attributed to a blockade of the PMA- and insulin-induced translocation of both GLUT1 and GLUT4 glucose transporters. The PMA-stimulated glucose transport activity was more sensitive to inhibition by staurosporine than was insulin-stimulated transport activity (PMA, IC50 = 1.1 +/- 0.1 microM; insulin, IC50 = 6.4 +/- 0.7 microM; P < 0.05, n = 3). At 1 microM staurosporine the insulin-sensitivity was decreased, i.e. EC50 increased from 0.12 nM to 5.4 nM, but the maximum response to insulin and the time course for stimulation were unaffected. At 6 microM staurosporine the insulin-sensitivity was further decreased, the maximal stimulation was decreased by 25%, and the apparent half-time for stimulation was extended from 2.5 min in control cells to 9.4 min. Staurosporine (30 microM) was able to block insulin's ability to stimulate glucose transport, whether added before or after insulin, by a mechanism that did not alter the rate of GLUT4 internalization. In intact adipose cells, staurosporine (30 microM) induced a slight (30%) decrease in the maximal insulin-induced receptor autophosphorylation and a similar decrease in the tyrosine phosphorylation of pp60 and pp160 (insulin-receptor substrate-1: 'IRS-1'), but was without effect on insulin binding to its receptor. Conversely, staurosporine induced a concentration-dependent inhibition of the constitutively tyrosine-phosphorylated (pp120) protein and of an insulin-stimulated protein pp53 in the cytosol. The locus of staurosporine's action appears to be distal from the initial insulin-receptor signalling, at a step that regulates the specific translocation of the glucose transporters to the plasma membranes.

Adipocytes↗

Cocirculation of two distinct groups of influenza C virus in Yamagata City, Japan.

The antigenic and genetic relationships among 15 strains of influenza C virus isolated between August, 1988, and May, 1990, in Yamagata City, Japan, were investigated. Based on the results of antigenic analysis with monoclonal antibodies to the hemagglutinin-esterase (HE) glycoproteins and oligonucleotide mapping of total vRNA, the isolates were divided into two distinct groups closely related to either C/Yamagata/26/81 or C/Aichi/1/81. Antigenic differences between two groups could be detected clearly with heterogeneous antiviral sera. Comparison of the HE gene sequences between the representative Yamagata isolates and the previous isolates from other countries showed that C/Yamagata/26/81-like and C/Aichi/1/81-like viruses had high degrees of nucleotide sequence homology with C/pig/Beijing/115/81 and C/Johannesburg/1/66, respectively. These observations suggest that two lineages of influenza C virus, markedly different from each other in both antigenic and genetic structures, were simultaneously present in Yamagata City during 1988-1990 and that viruses belonging to each of the two lineages may also be prevalent in other areas of Japan and even in other countries.

Amino Acid Sequence↗

Identification of regions of bovine factor VII essential for binding to tissue factor.

Initiation of the extrinsic blood coagulation pathway is mediated by a complex formed between plasma-derived factor VII/VIIa and cell-derived tissue factor (TF). To identify the site(s) of interaction, zymogen VII and VIIa were enzymatically and chemically modified, and their affinities for TF were estimated by measuring their inhibitory effects on the amidolytic activity enhanced after formation of the VIIa-TF complex. We found that the VIIa-light chain (Ki = 3.5 x 10(-7) M) and its fragment consisting of the gamma-carboxyglutamic acid (Gla)-domain and the first epidermal growth factor (EGF)-like domain (Gla-EGF1 peptide; Ki = 1.0 x 10(-6) M) have an affinity for TF. Therefore, one of the binding sites of VII with TF is probably located in the Gla-EGF1 region. On the other hand, a dansyl-Glu-Gly-Arg chloromethyl ketone-treated Gla-domainless VIIa (Ki = 0.7 x 10(-7) M) showed a high affinity for TF, whereas the corresponding Gla-domainless VII similarly treated showed no binding potential, thereby indicating that binding site(s) other than in the Gla-EGF1 region are present in VIIa but not in VII. Acetylation or carbamylation of the alpha-amino group of the NH2-terminal Ile-153 of VIIa resulted in the loss of binding affinity for TF; such modifications convert VIIa into a zymogen-like inactive form by destroying the salt bridge between Ile-153 and Asp-343 in VIIa. The rate of carbamylation of VIIa was reduced in the presence of TF. Protection of the alpha-amino group of Ile-153 from carbamylation after complex formation was consistent with salt bridge formation between Ile-153 and Asp-343 in the VIIa-TF complex. Therefore, binding of TF with the heavy chain of VIIa may induce a conformational change that brings the alpha-amino group of Ile-153 close to the beta-carboxyl group of Asp-343 to make a stable salt bridge.

1-Carboxyglutamic Acid↗