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Biomedical subjects

K Nakano

Publications and source records attributed to K Nakano.

At least 343 records · Page 19Linked to original sources
PubMed1995

Left ventricular function on exercise after surgical treatment of small aortic annuli.

To evaluate left ventricular function during exercise after aortic annular enlargement 15 patients with either aortic (group I, n = 8) or aortomitral (group II, n = 7) annuloplasty for small aortic annuli and eight patients (group III) with standard valve replacement for aortic stenosis without small aortic annuli received gated cardiac pool imagining by technetium-99m-labelled red blood cells at rest and during exercise at a mean of 23 months after operation. Left ventricular ejection fraction, preload requitable stroke work and stroke power index (preload requitable stroke work/systolic ejection period) were measured. Compared with resting values, left ventricular performance and stroke work rate on exercise after aortic annular enlargements increased significantly, as did those after standard aortic valve replacement. These results suggest that aortic annular enlargement can be indicated for surgical treatment of valvular heart diseases associated with small aortic annuli.

Adult↗
PubMed1995

Oxidative metabolism in Rett syndrome: 2. Biochemical and molecular studies.

In an attempt to identify a possible defect of mitochondrial metabolism in Rett syndrome we studied 9 girls with typical Rett syndrome using a clinical protocol designed to identify disorders of oxidative metabolism. One girl, (RO) had marked lactic acidemia. Biochemical studies on samples from these patients included leukocyte pyruvate carboxylase assay, serum biotinidase and skin fibroblast pyruvate production, pyruvate dehydrogenase, citrate synthetase and 2-oxoglutarate dehydrogenase assay. Muscle electron transport activities were studied on samples from 4 typical Rett patients including RO. Mitochondrial DNA (mtDNA) mutational analysis for the np3243 MELAS mutation, the np8993 NARP mutation, the np8344 MERFF mutation and the 4977 kb common deletion found in Kearns-Sayre syndrome and aged tissues were tested for in 1 of the muscle samples and 2 blood samples from typical Rett patients. Western blotting of electron transport complex III was performed on mitochondrial samples obtained from autopsy brain tissue in 2 Rett patients and compared to pediatric control brain samples. No abnormalities were found in blood biotinidase or pyruvate carboxylase. Western blotting of 2 Rett brain mitochondrial samples for complex III appear normal. Pyruvate consumption in medium from 8 Rett fibroblast lines grown with and without dichloroacetate (DCA) showed a normal fall in pyruvate suggesting normal pyruvate dehydrogenase activity in these cells, however the fibroblasts from patient RO had a high pyruvate production in culture. Pyruvate dehydrogenase, 2-oxo-glutarate dehydrogenase and citrate synthetase activities in 8 Rett fibroblast lines were normal.(ABSTRACT TRUNCATED AT 250 WORDS)

Blotting, Western↗
PubMed1995

Alteration of gamma-ray-induced chromosome aberration by 0.5 M NaCl in Chinese hamster cells.

Hypertonic treatment (0.5 M NaCl in phosphate-buffered saline, pH 7.2) at 37 degrees C for 20 min slightly delayed the mitotic frequency for non-irradiated cells in G1 and G2 phases. The mitotic frequency for irradiated cells in G2 was delayed by hypertonic treatment, and that in G1 was slightly delayed by hypertonic treatment. Hypertonic treatment in non-irradiated cells did not induce any chromosomal or chromatid aberrations in either G1 or G2. Chromosomal aberrations caused by gamma-irradiation were slightly enhanced by hypertonic treatment, and chromatid aberrations were markedly enhanced by hypertonic treatment. The enhancement ratio of gamma-irradiation-induced chromatid breaks and exchanges was 1.4 and 3.0, respectively. This cell cycle dependency of chromosome aberrations induced by postirradiation hypertonic treatment was the same as that of cell survival. These findings suggested that hypertonic treatment modifies the rejoining of DNA strand breaks in G2, but slightly modifies that in G1.

Animals↗
PubMed1995

Rare association of human papillomavirus DNA with esophageal cancer in Japan.

To examine whether human papillomavirus (HPV) DNA is associated with esophageal cancer, frozen and paraffin-embedded neoplasms of the upper aerodigestive tract, including esophageal cancer, were investigated. DNA obtained from frozen specimens and cell lines were analyzed by both polymerase chain reaction (PCR) and Southern blot hybridization. DNA from paraffin-embedded samples were analyzed strictly by PCR. DNA of HPV types 6 and 11 was detected in papillomas of the upper respiratory tract at > 50%. However, HPV DNA was infrequently detected in specimens from the upper digestive tract (31 esophageal cancers and 2 esophageal carcinoma--derived cell lines), even by PCR at a sensitivity of 0.1 copy number per cell. These results suggest that the etiologic significance of HPV infection in esophageal cancer is negligible.

Base Sequence↗
PubMed1995

Optimum culture conditions for production of exfoliative toxin by Staphylococcus hyicus.

Optimum culture conditions for the production of exfoliative toxin by Staphylococcus hyicus (shET) were examined. High shET activity was obtained from the culture filtrate of HI and TY broth inoculated with S. hyicus. The pH in these two media ranged from 7 to 8.5 during bacterial culture, while the lowest pH in TS and BHI broth was less than 6. shET activity in the culture filtrate from TY broth inoculated with 10(7) CFU of S. hyicus per ml was higher than that in TY broth inoculated with 10(6) and 10(8) CFU of bacteria per ml. When shET activity in the culture filtrate was measured under various shaking conditions, the culture filtrate shaken at 75 oscillations per min had the highest shET activity of the five shaking conditions. shET activity of the culture filtrate of TY broth to which protease inhibitor had been added was the same as that of TY broth without inhibitor. shET activity in a shaking culture in an Erlenmeyer flask was also the same as that in sac culture and that in shaking culture using a shaking (Sakaguchi) flask. shET activity in TY broth supplemented with 100 mM glucose was significantly lower than that in TY broth without glucose. Based on the above results, the optimum culture conditions for the production of shET were as follows: inoculation of 3 x 10(9) CFU of S. hyicus strain P-1 into 300 ml of TY broth in a 2,000-ml Erlenmeyer flask, and incubation at 37 C with shaking at 75 oscillations per min.(ABSTRACT TRUNCATED AT 250 WORDS)

Ammonium Sulfate↗
PubMed1995

Functional and T cell receptor gene usage analysis of cytotoxic T lymphocytes in fresh tumor-infiltrating lymphocytes from human head and neck cancer.

Twenty-one cytotoxic T lymphocyte (CTL) clones or lines that killed autologous tumor cells, but not allogeneic tumor, K562, or Daudi cells, were established from fresh tumor-infiltrating lymphocytes of two individuals (HP-1 and HP-2) with head and neck cancer by limiting dilution in the presence of recombinant interleukin-2. Sixteen (76%) of these 21 clones or lines comprised CD4+ CTLs and the other five comprised CD8+ CTLs. These observations suggest that autologous tumor cell-specific CD4+ CD8- and CD4- CD8+ CTLs are present in vivo at the tumor site in head and neck cancer. Analysis of T cell receptor (TCR) gene arrangements in 20 of the 21 CTL isolates with reverse transcriptase and the polymerase chain reaction revealed that five of 12 and five of eight isolates from HP-1 and HP-2, respectively, were clones, the other isolates being lines comprised of two or more clones. Each CTL clone showed a different combination of V alpha and V beta gene expression, suggesting that more than five different tumor-associated antigens may be expressed on head and neck cancer cells. In spite of the diversity of TCR alpha beta combinations, TCR V alpha 1, V alpha 3, V alpha 8, V alpha 10, V beta 8, V beta 9, and V beta 17 were also frequently expressed in both patients. These data suggest that specific CTLs proliferate oligoclonally and contribute to the specific immune response against head and neck cancer in vivo.

Antigens, Neoplasm↗
PubMed1995

Possible receptor for exfoliative toxins produced by Staphylococcus hyicus and Staphylococcus aureus.

Exfoliative toxin produced by Staphylococcus hyicus bound to the GM4-like glycolipid extracted from the skin of 1-day-old chickens but did not bind to glycolipid from adult chickens or suckling mice. Exfoliative toxin produced by Staphylococcus aureus bound to the GM4-like glycolipid extracted from the skin of suckling mice but not to glycolipid from 1-day-old or adult chickens. S. hyicus and S. aureus exfoliative toxins lost their toxicity by preincubation with GM4-like glycolipid from 1-day-old chickens and suckling mice, respectively.

Animals↗
PubMed1995

Analysis of a suppressor mutation ssb (kinC) of sur0B20 (spo0A) mutation in Bacillus subtilis reveals that kinC encodes a histidine protein kinase.

sur0B20 is a mutation that suppresses the effects of spo0B delta B or spo0F221 mutations in Bacillus subtilis, sur0B20 is an allele of the spo0A gene (Glu-14 to Val-14 conversion) and restores the sporulation of spo0B or spo0F mutants to the wild-type level. Here, we report the isolation of suppressor mutations of sur0B20 (ssb). One of these mutations, ssb-12, severely impairs the suppressor activity of sur0B20. A 2.5-kbp MboI fragment which complements the ssb-12 mutation was cloned by the prophage transformation method using phi CM as a vector. Nucleotide sequencing of the fragment revealed two open reading frames (orf1 and orf2). Gene disruption and complementation experiments showed that orf2 is the ssb gene. ssb was shown to encode a protein with a molecular weight of 48,846 (428 amino acid residues) showing strong similarity to transmitter kinases, especially KinA, of two-component regulatory systems. Therefore, ssb was renamed kinC. Deletion of kinC had no observable effect on sporulation. kinC transcription was induced at the onset of sporulation, probably from a sigma A-dependent promoter, and its expression was shut off at T3. DNase I protection experiments showed that the Spo0A protein binds to two adjoining sites in the kinC promoter region with different affinities. These results suggest that kinC expression might be regulated by Spo0A.

Amino Acid Sequence↗
PubMed1995

Deoxycholic acid in gall bladder bile does not account for the shortened nucleation time in patients with cholesterol gall stones.

The relations between the concentration of deoxycholic acid (DCA), the cholesterol saturation index, and the nucleation time in gall bladder bile were measured to determine the role of DCA in bile in the pathogenesis of cholesterol gall stone disease. Bile was obtained from patients with cholesterol gall stones (n = 30), subjects without gall stones (n = 35), and patients with pigment gall stones (n = 9). Three of 30 cholesterol gall stone patients and 10 of 35 gall stone free subjects were treated with antibiotics by mouth to decrease the concentration of bile DCA and determine the effect of DCA on biliary lithogenecity. Both the percentage and concentration of DCA in bile were similar in patients with and without cholesterol gall stones despite significant differences in their cholesterol saturation indices and nucleation times. Neither the percentage nor the concentration of DCA in bile correlated with either the cholesterol saturation index or the nucleation time. Analysis of subgroups with matching cholesterol saturation indices showed no correlation between the proportion of DCA in the bile and the cholesterol nucleation time. The proportion of DCA in bile was decreased by antibiotic treatment, but this had no effect on the cholesterol saturation index or nucleation time. These results suggest that DCA in bile is not responsible for biliary cholesterol saturation or cholesterol nucleation time.

Aged↗
PubMed1995

Hepatic cholesterol 7 alpha-hydroxylase activity and serum 7 alpha-hydroxy-cholesterol level during liver regeneration after partial hepatectomy in rats.

Hepatic cholesterol 7 alpha-hydroxylase is a rate-limiting enzyme for bile acid synthesis, and we have previously shown that the serum 7 alpha-hydroxycholesterol level reflects the enzyme activity in patients with an intact liver. The purpose of this study was to evaluate the alterations in hepatic cholesterol 7 alpha-hydroxylase activity and the serum 7 alpha-hydroxycholesterol level after hepatectomy and the correlations between these parameters and liver mass. Hepatic cholesterol 7 alpha-hydroxylase activity, the serum 7 alpha-hydroxycholesterol level and the remaining liver weight were determined after 70% hepatectomy in rats. Cholesterol 7 alpha-hydroxylase activity was decreased on days 1 and 2 (from 28.3 +/- 3.7 to 8.5 +/- 2.8 and 13.3 +/- 3.6 pmol/min/mg protein, respectively), returned to the preoperative level on day 3 (24.7 +/- 2.6 pmol/min/mg protein) and further elevated thereafter (71.4 +/- 10.9 on day 7 and 51.3 +/- 6.6 pmol/min/mg protein on day 14). The serum level of 7 alpha-hydroxycholesterol changed simultaneously with the enzyme activity, and a significant correlation between the two parameters was observed (r = 0.915, p < 0.0001). The correlations between the liver weight and hepatic cholesterol 7 alpha-hydroxylase activity and serum 7 alpha-hydroxycholesterol level were significant (p < 0.01), but the significances disappeared for the period of days 3-14 (r = 0.424, p = 0.08; r = 0.299, p = 0.228, respectively). In conclusion, hepatic cholesterol 7 alpha-hydroxylase activity is suppressed by hepatectomy and then activated as the liver regenerates. The serum 7 alpha-hydroxycholesterol level is a good parameter of this enzyme activity after partial hepatectomy.

Animals↗
PubMed1995

Crosslines, fluorophores in the AGE-related cross-linked proteins.

We can summarize our results as follows: (1) A pair of fluorescent crosslines were isolated from the Maillard reaction mixture; (2) AGE-proteins contained crossline-like structures, and (3) crossline-like immunoreactivities were accumulated in renal tissues of diabetic rats. From these results we concluded that fluorophores in AGE proteins have crossline-like structures and we had the first indication that XLs could be markers for renal disorders.

Animals↗
PubMed1995

Carbidopa/levodopa and selegiline do not affect platelet mitochondrial function in early parkinsonism.

Previous studies have demonstrated impaired complex I activity in platelets from Parkinson's disease (PD) patients who were receiving levodopa and other medications for their disease. Eleven patients with early PD underwent three sequential plateletphereses: while on no medication, after receiving carbidopa/levodopa for 1 month, and after receiving carbidopa/levodopa plus selegiline for 1 additional month. As expected, carbidopa/levodopa and selegiline significantly improved motor function in these patients. Treatment with carbidopa/levodopa alone and carbidopa/levodopa plus selegiline did not affect the activities of complexes I, II/III, and IV and citrate synthetase. These observations support the hypothesis that impaired complex I activity in PD patients is a characteristic of the disease and not due to medications.

Adult↗
PubMed1995

Histamine synthesis by cells of the macrophage lineage in bone marrow of mice.

An injection of Escherichia coli lipopolysaccharide (LPS) increased the activity of histidine decarboxylase (HDC) in bone marrow (BM) cells of C3H/HeN mice much more than in C3H/HeJ mice, which are resistant to various effects of LPS. In WBB6/F1 (W/Wv) mice, which are genetically deficient in mast cells, HDC activity increased more than in C3H/HeN mice. Cultured BM cells of W/Wv mice spontaneously synthesized histamine in a HDC-dependent way. LPS caused a slight increase in HDC-associated histamine synthesis by these cells. Treatment of the BM cells with murine recombinant granulocyte-macrophage colony stimulating factor (mrGM-CSF) increased the histamine synthesis. In addition, treatment with mrGM-CSF made the cells respond to LPS by a dose-dependent increase in HDC activity and histamine synthesis. Most dish-adherent BM cells that had been treated with both mrGM-CSF and LPS for 48 h were stained for nonspecific esterase and not for chloroacetate esterase, and had twice as much HDC activity as the nonadherent cells had. Immunocytochemical analysis of the BM cells of W/Wv mice treated with both mrGM-CSF and LPS showed that HDC was in the cytoplasm of cells having Mac-1, a macrophage-differentiation antigen. These results suggest that cells of the macrophage lineage in the BM of mice synthesize histamine.

Animals↗
PubMed1995

Interaction of tetrachloroethylene with rat hepatic microsomal P450-dependent monooxygenases.

1. We have studied the effects of tetrachloroethylene (PCE) on the kinetics of the P450-dependent monooxygenases in rat liver microsomes. 2. 7-Pentoxyresorufin O-depentylase (PROD) and 7-benzyloxyresorufin O-debenzylase (BROD) activities in phenobarbital (PB)-treated rat liver microsomes were substantially inhibited by PCE. The inhibition profiles were non-competitive for both enzyme activities; Ki's from Eadie-Hofsee plots were 0.16 and 0.29 mM for PROD and BROD respectively. In contrast, the enzyme activities in untreated, beta-naphthoflavone (BNF)-, isoniazid (ISN)- and pregnenolone-16 alpha-carbonitrile (PCN)-induced microsomes were not affected by PCE. 3. 7-Ethoxycoumarin O-deethylase (ECOD) activity in PB-induced microsomes was competitively inhibited by PCE, with a Ki that was lower than those of other microsomes. 4. PCE inhibited 7-ethoxyresorufin O-deethylase (EROD) activities in some microsomes slightly. The Ki for PCE was the lowest in untreated, followed by ISN-treated microsomes. 5. No effect of PCE upon aniline 4-hydroxylase (AN4H) and testosterone 6 beta-hydroxylase (TS6BH) activities was evident in any microsomal preparation. 6. These results indicate that PCE inhibits PB-inducible, P450-dependent monooxygenases in vitro non-competitively or competitively, and that the P450 enzymes of the P4502B subfamily may contribute to PCE toxicity.

Animals↗
PubMed1995

[A measurement scale for the Type A behavior pattern in women: the development of the Everyday Behavior Questionnaire].

A new 23-item scale, the Everyday Behavior Questionnaire (EDBQ) was developed to assess the Type A behavior pattern in women. Nurses (N = 139) in an university hospital participated in the validation study. Factor analysis of the 23 items revealed a four-factor structure. The four factors were anger/impatience, competitiveness/hard-driving, speed, and eagerness/interest. Internal consistency reliability estimates of four factors were adequate. Concurrent validity assessed by the relationship between the EDBQ and the Jenkins Activity Survey was significantly high. The four-factor structure and the relationship between the factors and psychological/physical symptoms adequately demonstrated Type A characteristics, as well as the uniqueness of the new questionnaire. These results suggested that the construct validity was in the desired direction. Further reliability and validity researches with the EDBQ in various samples were suggested.

Adult↗
PubMed1995

[Electronmicroscopic study on tongue squamous cell carcinoma--radiotherapy cases].

We examined the ultrastructures of the tongue squamous cell carcinomas which received radiotherapy and compared the metastatic cases with the non-metastatic cases. The results were as follows: 1. The non-metastatic cases were clinically T1N0 or T2N0 and histologically Grade I or II of the WHO classification. Electronmicroscopic observation of these cases revealed that numerous microvilli and a small number of desmosomes were found and the cell attachment seemed to be weak. These findings were different from those of the non-metastatic cases which received surgery. 2. In the metastatic cases of which the primary lesions were controlled, microvilli were not developed and a number of desmosomes were shown as compared with those in the non-metastatic cases. However, cell atypia and dispersion of the nuclear chromatin were clearly recognized.

Adult↗