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H Esaki

Publications and source records attributed to H Esaki.

At least 19 recordsLinked to original sources
PubMed2006

Drug resistance and random amplified polymorphic DNA analysis of Photobacterium damselae ssp. piscicida isolates from cultured Seriola (yellowtail, amberjack and kingfish) in Japan.

AIMS: To investigate the antimicrobial susceptibility and genetic characteristics of Photobacterium damselae ssp. piscicida isolates obtained from cultured Seriola in Japan. METHODS AND RESULTS: Minimal inhibitory concentrations of 14 antimicrobials for 74 isolates from Seriola in Japan in 2002 were determined. Isolates showed high frequencies of resistance to sulfamonomethoxine (SMMX) (97.3%), oxytetracycline (OTC) (77.0%), flumequine (FMQ) (77.0%), chloramphenicol (CP) (75.7%), kanamycin (KM) (63.5%) and oxolinic acid (OA) (62.0%), but low to ampicillin (ABPC) (2.8%). All isolates were susceptible to bicozamycin (BCM), fosfomycin (FOM) and florfenicol (FF). Of these isolates, 45 (60.8%) showed same resistance pattern (SMMX-OTC-FMQ-OA-CP-KM). In random amplified polymorphic DNA (RAPD) analysis, no difference was observed among our 74 field isolates and ATCC51736 isolated from Seriola in 1974 in Japan, but different from ATCC 17911 isolated from white perch in USA. CONCLUSIONS: FF, BCM, FOM and ABPC were useful antimicrobials for treating pseudotuberculosis. However, the frequency of multidrug resistance was high. RAPD analysis showed homogeneity of isolates from Seriola in Japan. SIGNIFICANCE AND IMPACT OF THE STUDY: This study demonstrates that some antimicrobials were still useful for treating pseudotuberculosis and that P. damselae ssp. piscicida strains of same origin might have spread among Seriola in Japan since 1974.

Animals↗
PubMed2005

Drug resistance and pulsed-field gel electrophoresis patterns of Lactococcus garvieae isolates from cultured Seriola (yellowtail, amberjack and kingfish) in Japan.

AIMS: To investigate the existing antimicrobial susceptibility and genetic characteristics of Lactococcus garvieae isolates from cultured Seriola in Japan. METHODS AND RESULTS: Minimum inhibitory concentrations (MICs) of 14 antimicrobial agents for 170 isolates were determined using the agar dilution method. Seventy-five isolates (44.1%) were simultaneously resistant to erythromycin (EM) (MIC>or=2 microg ml-1), lincomycin (LCM) (MIC>or=128 microg ml-1) and oxytetracycline (OTC) (MIC>or=4 microg ml-1). Resistance to EM was grouped as intermediate- and high-level resistant by MIC values. All resistant isolates possessed ermB and tet(S) genes. The number of different bands between pulsed-field gel electrophoresis patterns of 25 isolates and two ATCC strains (isolated in 1974), determined using two enzymes (ApaI and SmaI), did not exceed 3. CONCLUSIONS: The present resistance pattern observed with ermB and tet(S) is similar to that observed in previous reports. Moreover, the genetic characteristics of L. garvieae isolates from a wide area in Japan in 2002 and ATCC strains were closely related. SIGNIFICANCE AND IMPACT OF THE STUDY: This study suggests that EM-, LCM- and OTC-resistant isolates have been present for 15 years and that L. garvieae strains with same origin have spread among Seriola spp. in Japan since 1974.

Animals↗
PubMed2002

Glutathione-S-transferase activity toward aflatoxin epoxide in livers of mastomys and other rodents.

In order to study the liver glutathione-S-transferase (GST) activity toward aflatoxin B1 (AFB1) epoxide in mastomys in comparison with other rodents, we performed in vitro studies of the cytosolic GST activity toward AFB1-epoxide using mastomys, rat, mouse and hamster liver. Also AFB1 metabolism by liver microsomes including formation of AFB1-DNA adducts was studied. Cytosolic GST activity toward AFB1-epoxide was highest in mastomys liver, and higher in the hamster and mouse livers than in the rat liver, correlating well with the differences of the sensitivity of these species to the toxicity of AFB1. However, no relationship was noted between the sensitivity of a given species to the toxicity of AFB1 and the microsomal activity of binding of AFB1 to DNA or metabolizing AFB1 to AFM1, AFQ1 and AFP1. These results demonstrate the importance of the GST mediated AFB1-epoxide conjugation with glutathione in determining the differing sensitivities of these species to AFB1 toxicity. The extremely high activity of GST in mastomys indicates that this species would be a good model animal for studying GST toward AFB1-epoxide.

Aflatoxin B1↗
PubMed1999

New potent antioxidative o-dihydroxyisoflavones in fermented Japanese soybean products.

A potent antioxidative 6-hydroxydaidzein (6-OHD) was newly isolated from soybean koji fermented with Aspergillus oryzae. 6-OHD, in addition to 8-hydroxydaidzein and 8-hydroxygenistein, were found to be present in various fermented soybean products, including their koji. Considering that these o-dihydroxyisoflavones had strong antioxidative activities, they may contribute to protecting from oxidative deterioration during the processing of fermented soybean products.

Antioxidants↗
PubMed1999

[A study of the long-term effectiveness of an outpatient pulmonary rehabilitation program].

Pulmonary rehabilitation is one of the most important components of comprehensive care for patients with significant disability due to chronic respiratory failure. Because pulmonary rehabilitation has not been popular in Japan, the long-term effectiveness of pulmonary rehabilitation has rarely been reported. We therefore examined the long-term effectiveness of an outpatient pulmonary rehabilitation program for patients with chronic respiratory failure. Our program was composed of a once-a-week introduction program for 2 months and a support program that was continued every 4 weeks as long as possible. Thirty stable patients with chronic respiratory failure were enrolled in the program; 21 patients (COPD: 15, lung complications of tuberculosis: 6) completed the 9-week introduction program and the ensuing 6-month support program. Good compliance with the home training regimen was maintained during the period. The introduction program significantly alleviated dyspnea (Fletcher's grade: 3.3 to 3.0, p < 0.01) and improved the data for activity (Spector's score: 5.3 to 5.8, p < 0.01) and 6-minute walking distance (319 to 384 m, p < 0.01). These benefits were sustained during the 6-month support program. We concluded that outpatient pulmonary rehabilitation can alleviate dyspnea and improve the activity and exercise tolerance of patients with chronic respiratory failure, and that the effectiveness of training can be well maintained with a minimal support program.

Activities of Daily Living↗
PubMed1998

[A prospective study on the relationship between body mass index and mortality in middle-aged and elderly people in Japan].

We conducted a prospective study to clarify the relationship between mortality and body mass index (BMI) in a middle-aged and elderly population in Japan. The subjects included 12,649 people (5,686 males and 6,963 females) aged from 40-69 years, who were identified by a mail survey between 1987 and 1989, and thereafter were followed up from the date of the survey until February 28, 1995. Cox's proportional hazards model was used to adjust for age, smoking status, drinking habit and occupation, and hazard ratios were calculated for total mortality and cancer mortality based on levels of BMI, while using a BMI of 22 to approximately 24 as a reference level. Results showed a U shaped relationship between BMI and total mortality in females. Females demonstrated a minimal total mortality in the reference group, but a significantly high hazard ratio in the lowest group of BMI < 20 (hazard ratio = 1.95, p < 0.01) and the highest group of BMI > or= 26 (hazard ratio = 1.71, p < 0.01). On the other hand, males did not demonstrate such a U shaped relationship, but instead showed an L shaped relationship between BMI and total mortality. Males showed a minimal total mortality at a BMI of 24 of approximately 26 (hazard ratio = 0.92), but a significantly high hazard ratio in the lowest BMI group (hazard ratio = 1.57, p < 0.01). In contrast, an elevated hazard ratio was not observed in the highest BMI group (hazard ratio = 1.05). The relationship between BMI and cancer mortality was found to be similar to the relationship between BMI and total mortality in both males and females. Our findings suggest that moderate overweight may be a sign of good health among both middle-aged and elderly men in Japan.

Adult↗
PubMed1997

Characteristics of laryngeal receptors analyzed by presynaptic recording from the cat medulla oblongata.

In order to clarify the neural mechanisms for the protective laryngeal reflex, we conducted physiological analysis of laryngeal sensory receptors. In the present study, presynaptic unit activities, which might accurately reflect characteristics of the laryngeal receptor, were recorded with a glass microelectrode in the nucleus of the tractus solitarius of the medulla oblongata in ketamine-urethane anesthetized cats, and the responses to the mechanical and/or chemical stimuli were analyzed. From the results, it was demonstrated that highly sensitive mechanoreceptors and polymodal receptors exist in the laryngeal mucosa; they are particularly numerous in the laryngeal surface of the epiglottis and arytenoid region, and uncommon in the vocal fold. Mechanoreceptors on the laryngeal mucosa were classified into a rapidly adapting group and a slowly adapting group, while all polymodal receptors adapted rapidly to mechanical stimulation. These results suggest that these non-specific polymodal and rapidly adapting receptors may correspond to more superficial receptors such as free nerve endings and some taste buds, and also monomodal slowly adapting mechanoreceptors may correspond to deeper terminals in the subepithelium. It is also considered possible that the structures and the characteristics of these receptors are appropriate to elicit the protective laryngeal reflexes by non-specifically detecting various kinds of stimuli.

Animals↗
PubMed1997

Activity of H(+)-ATPase in ruminal bacteria with special reference to acid tolerance.

Batch culture experiments showed that permeabilized cells and membranes of Ruminococcus albus and Fibrobacter succinogenes, acid-intolerant celluloytic bacteria, have only one-fourth to one-fifth as much H(+)-ATPase as Megasphaera elsdenii and Streptococcus bovis, which are relatively acid tolerant. Even in the cells grown in continuous culture at pH 7.0, the acid-intolerant bacteria contained less than half as much H(+)-ATPase as the acid-tolerant bacteria. The amounts of H(+)-ATPase in the acid-tolerant bacteria were increased by more than twofold when the cells were grown at the lowest pH permitting growth, whereas little increase was observed in the case of the acid-intolerant bacteria. These results indicate that the acid-intolerant bacteria not only contain smaller amounts of H(+)-ATPase at neutral pH but also have a lower capacity to enhance the level of H(+)-ATPase in response to low pH than the acid-tolerant bacteria. In addition, the H(+)-ATPases of the acid-intolerant bacteria were more sensitive to low pH than those of the acid-tolerant bacteria, although the optimal pHs were similar.

Animals↗
PubMed1997

Antioxidative mechanism and apoptosis induction by 3-hydroxyanthranilic acid, an antioxidant in Indonesian food Tempeh, in the human hepatoma-derived cell line, HuH-7.

Recently, a new potent antioxidant was isolated from Tempeh (a traditional fermented soybean food in Indonesia) and was identified as 3-hydroxyanthranilic acid (HAA). This study deals with the antioxidant mechanism of HAA under biological systems and the cytokilling function of HAA to human malignant cells. HAA eliminated free radicals and inhibited the formation of fatty acid hydroperoxide in vitro, suggesting that HAA would serve as an antioxidant in the initial reaction in lipid oxidation systems. Actually, HAA inhibited the formation of the dominant product of membrane lipids, 12-hydroxyeicosatetraenoic acid (12-HETE) at a high concentration, while HAA accelerated 12-HETE formation at a low concentration in mammalian tissue. HAA oxidized glutathione and inhibited superoxide dismutase in vitro. Furthermore, HAA inhibited cell growth and induced apoptosis to HuH-7, a human hepatoma-derived cell line. As long as HAA is taken as a component of Tempeh, and not in large doses as a chemical, it may possibly act as a prooxidant rather than an antioxidant in vivo.

12-Hydroxy-5,8,10,14-eicosatetraenoic Acid↗
PubMed1997

Dengue hemorrhagic fever in Jakarta, Indonesia in 1988: isolation of dengue virus from patient whole blood using cell cultures.

During an outbreak of dengue hemorrhagic fever (DHF) in Jakarta, Indonesia in 1988, we attempted to isolate dengue virus using mosquito cells and a medium containing heparin. Whole blood, immediately after being drawn from patients, was inoculated into Aedes albopictus cell cultures temporarily maintained in the heparin-containing medium. The overall virus isolation rate was 25% (17 of 69) samples collected within three days after admission of the patients to hospital. No virus was obtained thereafter. The successful virus isolation was apparently not related to titers of anti-dengue virus hemagglutination-inhibiting antibodies present in patients' sera. The viruses were recovered from cases of each of the four World Health Organization grades of DHF without significant differences. The technique is simple and easily performed at bedside.

Aedes↗
PubMed1995

A prospective study on mortality among Japanese coal miners.

We conducted a prospective study to clarify mortality patterns among Japanese coal miners in a former coal mining area. Subjects included 1,796 coal miners and 4,022 non-coal-miners, who were identified by a mail survey between 1987 and 1989, and then followed up from the date of the survey to April 30th, 1994. We applied Cox's proportional hazards model to compare the mortalities between coal miners and non-coal-miners. Among the coal miners, significantly high risk ratios were observed in all causes of death (risk ratio = 1.4, p < 0.05) and all malignant neoplasms (risk ratio = 1.5, p < 0.05). Risk ratios for all causes of death and all malignant neoplasms also rose with the length of experience in coal mining. Analysis of the results for sites of cancer showed that coal miners had high risk ratios for stomach cancer (risk ratio = 1.6), liver cancer (risk ratio = 1.4) and lung cancer (risk ratio = 1.6), though these ratios were not statistically significant. When the risk ratio for lung cancer was analyzed according to the length of experience in coal mining, coal miners with at least 15 years' experience had a significantly high risk ratio (risk ratio = 2.4, p < 0.05), though coal miners with less than 15 years' experience had almost the same risk as non-coal-miners.

Adult↗
PubMed1994

Hepatitis B surface antigen, hepatitis C virus antibody, body mass index, and alcohol drinking among workers with elevated serum alanine aminotransferase.

METHODS: We conducted a case-control study on liver diseases among Japanese workers to examine associations between elevated serum alanine aminotransferase (alanine aminotransferase value > or = 50 IU/liter) and selected factors such as hepatitis B surface antigen positive, hepatitis C virus antibody positive, body mass index, and alcohol drinking. Out of 3,738 workers (1,477 males and 2,261 females) in a supermarket chain, 91 workers with an elevated serum alanine aminotransferase value (> or = 50 IU/liter) were classified as cases and 182 workers with normal serum alanine aminotransferase value and without an episode of blood transfusion were randomly selected as controls. RESULTS: Prevalence rates of hepatitis B surface antigen positive and hepatitis C virus antibody positive were 4.4 and 23.1% among the overall cases, 2.9 and 11.8% among the cases with 100 > alanine aminotransferase value > or = 50, and 8.7 and 56.5% among the cases with alanine aminotransferase value > or = 100. A logistic regression analysis was conducted. Odds ratios were 4.94 for hepatitis B surface antigen positive (P < 0.05) and 77.19 for hepatitis C virus antibody positive (P < 0.001). Odds ratios for body mass index increased with increasing body mass index values; 3.32 for 26 > body mass index > or = 24 (P < 0.01) and 5.03 for body mass index > or = 26 (P < 0.001). No increased risk was observed among regular drinkers of less than 27 g/day of ethanol (odds ratio is 0.23) or of 27-53 g/day of ethanol (odds ratio is 0.47). A slightly increased odds ratio of 1.35 was observed among regular drinkers of 54-81 g/day of ethanol, but this was not statistically significant. CONCLUSIONS: Our results suggest that hepatitis C virus and high body mass index are predominant factors in elevated serum alanine aminotransferase levels among Japanese workers, while alcohol drinking is a minor factor.

Adult↗
PubMed1993

Secondary spontaneous pneumothorax.

To assess the clinical manifestations and therapy of secondary spontaneous pneumothorax (SSP), 123 episodes of SSP in 67 patients were retrospectively reviewed and were compared with 254 episodes of primary spontaneous pneumothorax in 130 patients. The major underlying lung diseases associated with SSP were emphysema (22 patients) and tuberculosis (21 patients). The average age of patients with SSP was 66.8 years, and the most common symptom was dyspnea. The average arterial oxygen tension at onset of SSP was 61.1 +/- 12.1 mm Hg (mean +/- standard deviation), which was lower than that of patients with primary spontaneous pneumothorax (p < 0.01). The recurrence rate of open thoracotomy with pleural abrasion was 12.5% (3 of 24 episodes), which was not lower than that of thoracostomy tube drainage with chemical pleurodesis using tetracycline (recurrence rate, 18.8%) (p > 0.5). We concluded that considering the high age of the patients, the presence of underlying lung diseases, and the increased operative risk, thoracostomy tube drainage rather than open thoracotomy was preferred as the first choice of therapy for SSP.

Adolescent↗
PubMed1993

[An epidemiological study of tuberculosis in the former coal mining area of Chikuho. II. A case-control study on the relationship between socioeconomic factors and tuberculosis].

The authors conducted a case-control study on the relationship between socioeconomic factors and tuberculosis in the former coalmining area of Chikuho where tuberculosis incidence was high. The cases were 292 newly registered tuberculosis patients in Iizuka Health Center District, in the former coalmining area of Chikuho. Controls were randomly selected from resident cards, matched for sex, age, and place of residence. The results of comparing the cases with the controls were as follows: 1) Significantly more of the male cases had had long-term employment in coalmining. Exposure to dust is likely to be associated with the high tuberculosis incidence in males aged 50 or over. 2) The cases showed significantly higher unemployment levels and lower educational levels. Among females, more of the cases were unmarried or divorced, and a significantly higher proportion were receiving welfare benefits. The high incidence of tuberculosis is probably related to a low socioeconomic level resulting from closure of coalmines. 3) No difference was observed in working hours, night shifts, smoking rate, and drinking habits. These factors are unlikely to be singly related to the onset of tuberculosis.

Adolescent↗
PubMed1993

[An epidemiological study of tuberculosis in the former coal-mining area of Chikuho. I. An analysis of newly registered tuberculosis patients in Iizuka Health Center District].

To clarify risk factors and groups at high risk of tuberculosis, a study on tuberculosis was conducted in the former coalmining area of Chikuho, where the death rate from tuberculosis was high. The authors analysed 701 newly registered tuberculosis patients during the 5 years from 1982 through 1986 in Iizuka Health Center District in the Chikuho area, studied the geographical distribution of tuberculosis incidence in Fukuoka Prefecture, and compared the trends of tuberculosis incidence in Iizuka Health Center District, all Japan and Fukuoka Prefecture. The results were as follows: 1) The incidence of tuberculosis in Iizuka Health Center District was higher than those both in all Japan and in Fukuoka Prefecture. The incidence in Iizuka Health Center District has not decreased since 1981. Therefore, the difference in tuberculosis incidence between Iizuka Health Center District, and all Japan and Fukuoka Prefecture has gradually become greater. The incidence of tuberculosis in 1986 was 81.6 (per 100,000) in Iizuka Health Center District, 58.1 in Fukuoka Prefecture, 46.6 in all Japan. 2) A specific pattern was observed in the geographical distribution of tuberculosis incidence in Fukuoka Prefecture. A high incidence was concentrated in the former coalmining area of Chikuho. 3) The positive rate of tubercle bacilli (38.8%) was the same as that in all Japan. However, the positive rate was higher in age groups 10-49 than that in all Japan. 4) A total of 83.5% of tuberculosis cases were detected when visiting doctors, mainly with complaints of cough, fever and sputum. Only 6.9% of the patients were detected by screening examinations.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1990

[A malignant thymoma combined with sarcoidosis].

A case of 69-year-old female of malignant thymoma with sarcoidosis was experienced. Although many diseases such as myasthenia gravis are associated with thymoma, sarcoidosis is a rare thymoma-associated disease. Only one case of thymoma with sarcoidosis was reported all over the world, and our case is the first case in Japan. As thymus is essential for the development of T lymphocytes, thymoma may cause T lymphocytes disorder and sarcoidosis. So, we consider thymoma with sarcoidosis as a syndrome rather than as a spectrum of coincidental disease.

Aged↗
PubMed1990

[Four cases of spontaneous hemopneumothorax].

We reported four cases of spontaneous hemopneumothorax. Of these, one (a 25-year-old man) had right hemopneumothorax and three (a 28-year-old man, a 21-year-old woman and a 24-year-old man) had left hemopneumothorax. In one case, because massive intrapleural bleeding had continued, an emergency operation was performed. In two cases, thoracotomy was performed because of recurrent pneumothorax. In the other case, about one week after hemopneumothorax had been controlled by pleural drainage, pneumothorax recurred and thoracotomy was performed. In conclusion, early thoracotomy is the best treatment for spontaneous hemopneumothorax.

Adult↗