Search PubMed⌕ Search

Biomedical subjects

N Kinoshita

Publications and source records attributed to N Kinoshita.

At least 73 records · Page 4Linked to original sources

Effects of diltiazem on myocardial perfusion abnormalities during exercise in patients with hypertrophic cardiomyopathy.

The effect of diltiazem on myocardial ischemia in patients with hypertrophic cardiomyopathy (HCM) was evaluated by exercise myocardial 201Tl single photon emission computed tomography (SPECT). Exercise myocardial SPECT was performed before and 8 weeks after oral administration of diltiazem (180 mg/day) in 20 patients with HCM who showed transient perfusion defects on exercise myocardial 201Tl SPECT under control conditions. SPECT images were divided into 17 segments. The 201Tl perfusion defects were visually scored and evaluated as the defect score. The transient dilation index was calculated as an index of subendocardial ischemia. Improvement of the defect score was demonstrated in 15 patients after the administration of diltiazem. The mean defect score decreased significantly from 9.90 +/- 5.17 to 5.50 +/- 4.89 (p < 0.0001). Although 16 of 20 patients showed an abnormal transient dilation index before diltiazem treatment, 16 showed improvement and 13 of these normalized after diltiazem therapy. The mean transient dilation index decreased from 1.16 +/- 0.10 to 1.02 +/- 0.09 (p < 0.0001). In conclusion, diltiazem prevents or diminishes myocardial ischemia in patients with HCM.

Adult↗

The risk of hepatitis C virus infection among blood donors in Osaka, Japan.

To estimate the risk of hepatitis C virus (HCV) infection among blood donors, we conducted a retrospective cohort study with 448,020 HCV-seronegative donors who donated blood more than once between February 1992 and July 1997 in Osaka (a total of 2,676,738 allogeneic blood donations). The donors were divided into four age groups according to the age at the initial donation: Group A (16-24 years), Group B (25-34 years), Group C (35-49 years) and Group D (50-64 years). Fifty-nine donors became infected with HCV among the 448,020 HCV-seronegative donors who donated blood more than once within a period of approximately five years. In a total of 1,095,668 person-years of observation (PYO), the incidence rate was 5.38 per 105 PYO, with the 95% confidence interval (95% C.I.) being 4.10 to 6.95. There was no significant difference in the incidence rate between males and females. Young donors between the ages of 16 and 24 (8.89; 95% C.I., 6.04 to 12.61) had a significantly higher incidence rate of HCV infection than donors between the ages of 35 and 49 (1.81; 0.67 to 3.95). The cumulative risk of HCV infection among donors between the ages of 16 and 64 was estimated to be 0.27% (95% C.I., 0.16 to 0.39) for males and 0.27% (95% C.I., 0.15 to 0.38) for females. Based on the recent age-specific incidence rate, the cumulative risk of HCV infection among blood donors was estimated to be about 0.3% in the Osaka district of Japan. The incidence rate differed among age groups, indicating that HCV infection is associated with age-related behaviors and the need for further epidemiological research towards the eradication of community-acquired HCV infection.

Adolescent↗

Diperamycin, a new antimicrobial antibiotic produced by Streptomyces griseoaurantiacus MK393-AF2. I. Taxonomy, fermentation, isolation, physico-chemical properties and biological activities.

Antibacterial antibiotics, diperamycin (1) was produced in the culture broth of Streptomyces griseoaurantiacus MK393-AF2. Various spectroscopic analyses of 1 suggested that 1 belonged to a member of cyclic hexadepsipeptide antibiotic. Antibiotic 1 had potent inhibitory activity against various Gram-positive bacteria including Enterococcus seriolicida and methicillin-resistant Staphylococcus aureus.

Animals↗

Cremimycin, a novel 19-membered macrocyclic lactam antibiotic, from Streptomyces sp.

A novel 19-membered macrocyclic lactam antibiotic, cremimycin, was isolated from the culture broth of an actinomycete strain. The producing organism, designated MJ635-86F5, was identified as a member of Streptomyces. Cremimycin was isolated from the mycelial cake by extraction with CHCl3-MeOH and precipitation with hexane-MeOH. The structure of cremimycin was determined by spectroscopic study. Cremimycin showed broad antimicrobial activities against Gram-positive bacteria including MRSA.

Animals↗

Nothramicin, a new anthracycline antibiotic from Nocardia sp. MJ896-43F17.

A new antibiotic designated nothramicin was isolated from the culture broth of Nocardia sp. MJ896-43F17 which was closely related to Nocardia brasiliensis. It was isolated by the Diaion HP-20 column chromatography, butyl acetate extraction and purified by HPLC. It inhibited the growth of mycobacteria at the concentration of 1.56 approximately 25 microg/ml. Nothramicin was revealed to be a new member of anthracycline antibiotics by the various spectroscopies.

Animals↗

Polyketomycin, a new antibiotic from Streptomyces sp. MK277-AF1. I. Taxonomy, production, isolation, physico-chemical properties and biological activities.

A new antibiotic designated polyketomycin was isolated from the culture broth of Streptomyces sp. MK277-AF1. It was purified by ethyl acetate extraction, Sephadex LH-20 column chromatography and centrifugal partition chromatography (CPC). It inhibited growth of Gram-positive bacteria including methicillin-resistant Staphylococcus aureus (MRSA). Its MICs were less than 0.2 microgram/ml. Polyketomycin exhibited cytotoxic activity against nine tumor cell lines at concentrations of 0.9-5.2 micrograms/ml.

Anti-Bacterial Agents↗

Epostatin, new inhibitor of dipeptidyl peptidase II, produced by Streptomyces sp. MJ995-OF5. I. Taxonomy of producing strain, fermentation, isolation, physico-chemical properties and biological properties.

A new inhibitor of dipeptidyl peptidase II (DPP-II, EC 3.4.14.2), designated as epostatin, was discovered in the fermentation broth of a strain isolated in our institute. The strain has been identified as Streptomyces sp. MJ995-OF5 on the basis of taxonomic studies. Epostatin was obtained as a yellow powder after seqential purification by chromatography on Diaion HP-20, n-butanol extraction, Sephadex LH-20 column chromatography and centrifugal partition chromatography (CPC). Epostatin inhibited DPP-II competitively in a dose dependent manner. The compound was slightly inhibitory against other dipeptidyl peptidases.

Alanine↗

A 7.6kb DNA region from Streptomyces kasugaensis M338-M1 includes some genes responsible for kasugamycin biosynthesis.

A 7.6kb PstI-KpnI DNA fragment including a sequence highly similar to kasugamycin acetyltransferase gene (kac) was isolated from Streptomyces kasugaensis M338-M1 and sequenced. Nine open reading frames (ORFs), designated as ORF A, B, C, D, E, F, G, H and I, were recognized in this region, although ORF A was incomplete. ORF G runs in the opposite direction to the others. The amino acid sequence deduced from ORF H showed 98% similarity to that of the kasugamycin acetyltransferase from S. kasugaensis MB273-C4, another kasugamycin (KSM) producer. Transformation of E. coli JM109 with ORF H made the strain highly resistant to KSM. The deduced amino acid sequences of the ORF A, C and D products were similar, respectively, to glucosyltransferase I from E. coli (26%), beta-alanine: pyruvate transaminase from Pseudomonas putida (32%) and dTDP-D-glucose 4,6-dehydratase (StrE) from Streptomyces griseus (37%). The strE-like ORF (ORF D) seems to be the gene responsible for formation of the 6-deoxy structure of the kasugamine moiety. ORF A and ORF C are also likely to have roles in KSM biosynthesis. Taken together, our analyses strongly suggest that this DNA region includes at least a part of the gene cluster of KSM biosynthesis.

Amino Acid Sequence↗

[Smoking behavior and cognition for smoking cessation after diagnosis of head and neck cancer or stomach cancer].

This study aims at describing smoking behavior and cognition for smoking cessation among Japanese men after the diagnosis of cancer. Subjects were 144 patients with head and neck cancer (oral cavity, pharynx and larynx without requirement of total laryngectomy) and 104 patients with stomach cancer who were current or ex-smokers at time of diagnosis. A self-administered questionnaire was mailed at least 1.5 years alter diagnosis. Response was by mail and 72% (248/344) of completed questionnaires were returned. Among 164 patients who were smokers at the time of diagnosis, 59(36%) reported that they continued to smoke after the diagnosis of cancer. Stomach cancer patients (53%) had significantly higher (p < 0.01) continuance rate of smoking than head and neck cancer patients (24%), and patients in fifties (53%) had the highest continuance rate of smoking in the study participants. Among 105 patients who were abstinent, 83(79%) had stopped smoking within 6 months after the diagnosis of cancer. Interest in smoking cessation among the current smokers was high (83%), and they preferred a smoking cessation class with multiple participants to "person to person" counseling provided by health care practitioners.

Aged↗

Occurrence of sustained increase in QT dispersion following exercise in patients with residual myocardial ischemia after healing of anterior wall myocardial infarction.

Our objective was to evaluate the effect of exercise on QT dispersion over the next 3 hours, as seen on a standard 12-lead electrocardiogram in patients with healed myocardial infarction with or without residual ischemia. We measured QT and QTc dispersion before, immediately after, and 1 and 2 hours after symptom-limited, dynamic treadmill exercise tests in 28 patients with healed anterior wall myocardial infarction with (group I, n = 18) and without (group II, n = 10) residual ischemia. The same protocol was followed in 5 group I patients after successful performance of coronary angioplasty. QT and QTc dispersion did not change immediately after exercise in group II. These parameters increased in group I (QT dispersion at rest [mean +/- SD] 57 +/- 22 ms, and after exercise 87 +/- 27 ms; QTc dispersion at rest 62 +/- 25 ms, and after exercise 114 +/- 36 ms). The increases in QT and QTc dispersion were sustained for at least 2 hours. After a successful coronary angioplasty in 5 patients, these parameters no longer increased with exercise. Thus, QT dispersion increased for at least 2 hours after exercise in patients who had residual ischemia after healing of myocardial infarction. Data obtained in 5 of these patients after coronary angioplasty support the idea that residual ischemia plays a key role in the sustained increase in QT dispersion after exercise.

Aged↗

In vivo but not in vitro stimulations rescue of the defective class switching to IgG or IgA in B-cells of immunodeficiency with hyper IgM.

In an X-linked immunodeficiency with hyper IgM (X-HIM), several mutations of genes coding for CD40 ligand are responsible for B-cell defects. However, it is controversial whether the defective class switching from IgM to IgG or IgA but not IgE is rescued by in vitro stimulations or not. In six X-HIM patients, signaling through CD40 induced IgE but not IgG or IgA secretion in vitro. When transferred into SCID mice, however, B-cells of X-HIM patients secreted as much IgG and IgA as those of healthy controls. Moreover, sIgG and sIgA expressions were also induced by the in vivo stimulation. These results support that B-cells of X-HIM patients are defective of in vitro class switching from IgM to IgG or IgA and show that the in vivo stimulations rescue the defective class switching and suggest that the class switching of IgE and that of IgG or IgA might be regulated quite differently.

Animals↗

The reproducibility of color Doppler duplex sonography in the measurement of renal arterial blood velocity.

In this study, the reproducibility of color Doppler duplex sonography for repeated measurements of renal blood flow was evaluated in 14 healthy subjects. We examined the reproducibility for different examiners and different time intervals between the examinations. Doppler frequency sonograms were analyzed with several parameters, and statistical evaluation was performed by calculating both the correlation coefficient (r) and coefficient of variation (CV). Peak systolic velocity (S), early diastolic velocity (D1) and mean velocity (MV) showed good reproducibility (r = 0.902-0.992, CV = 2.15-8.16%). On the other hand, end-diastolic velocity (D2), acceleration time (AT) and acceleration index (AI) showed poor reproducibility. We conclude that the reproducibility of this method is acceptable for repeated measurements of renal blood velocity, using suitable parameters S, D1 and MV.

Adult↗

Second primary cancers following non-Hodgkin's lymphoma in Japan: increased risk of hepatocellular carcinoma.

We evaluated the risk of development of second primary cancers, with particular reference to subsequent hepatocellular carcinoma (HCC), in 592 patients diagnosed as non-Hodgkin's lymphoma (NHL), at Osaka Medical Center for Cancer and Cardiovascular Diseases. During 1978-1994, 2,163 person-years of observation were accrued, and 27 of the patients developed a second primary cancer, yielding an observed-to-expected ratio (O/E) of 1.53 [95% confidence interval (CI) = 1.01-2.23]. Significant excess risk was noted for primary liver cancer (PLC; O/E = 4.36, 95% CI = 1.99-8.28; O = 9) and non-lymphocytic leukemia (O/E = 26.17, 95% CI = 5.26-76.46; O = 3). The excess risk of PLC was relatively constant within the first 10 years after the NHL diagnosis. Patients who received chemotherapy as the NHL treatment had a significantly increased risk of PLC (O/E = 5.91, 95% CI = 2.70-11.23; O = 9). Their clinical reports indicated that all nine patients with PLC were diagnosed as HCC, and eight of them had clinical and/or histologic evidence of cirrhosis at the time of HCC diagnosis. None of the nine patients had a history of blood transfusion between the first NHL treatment and the diagnosis of HCC. These findings suggested that Japanese NHL patients might have an increased risk of developing HCC, and they indicated the importance of medical surveillance for liver malignancies, as well as subsequent leukemias. Possible explanations for the excess risk of subsequent HCC are discussed.

Adult↗

Resormycin, a novel herbicidal and antifungal antibiotic produced by a strain of Streptomyces platensis. I. Taxonomy, production, isolation and biological properties.

Resormycin, a novel herbicidal and antifungal antibiotic, was isolated from the cultured broth of streptomycete strain. The strain was isolated from a soil collected at Yokohama-shi, Kanagawa Prefecture, Japan, and identified as Streptomyces platensis MJ953-SF5. Resormycin was purified by active charcol, Amberlite IRC-50, Amberlite CG-50 and Sephadex LH-20 column chromatographies. Resormycin markedly inhibited the growth of monocotyledonous and dicotyledonous weed. The antibiotic showed antimicrobial activity against phytopathogenic fungi.

Antifungal Agents↗

Epoxyquinomicins A, B, C and D, new antibiotics from Amycolatopsis. I. Taxonomy, fermentation, isolation and antimicrobial activities.

A new structural class of the antibiotic, epoxyquinomicins A, B, C and D were isolated from the culture broth of the strain MK299-95F4, which was related to Amycolatopsis sulphurea. Antimicrobial activity of epoxyquinomicins A and B were weak against Gram-positive bacteria, and epoxyquinomicins C and D showed almost no antimicrobial activity and no cytotoxicity. All these antibiotics showed improvement of collagen induced arthritis in vivo.

Actinobacteria↗

Formamicin, a novel antifungal antibiotic produced by a strain of Saccharothrix sp. I. Taxonomy, production, isolation and biological properties.

Formamicin, an antifungal antibiotic, was isolated from the cultured broth of an actinomycete strain. The strain was isolated from a soil collected at Setagaya-ku, Tokyo, Japan, and identified as Saccharothrix sp. MK27-91F2. Formamicin was extracted with acetone from cultured mycelia and purified by silicagel and Sephadex LH-20 column chromatographies and CPC (Centrifugal liquid-liquid Partition Chromatography). Formamicin showed strong antimicrobial activity against phytopathogenic fungi.

Actinomycetales↗