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Biomedical subjects

A Okayama

Publications and source records attributed to A Okayama.

At least 55 records · Page 3Linked to original sources

Rapid quantification of HTLV-I provirus load: detection of monoclonal proliferation of HTLV-I-infected cells among blood donors.

In this report, we quantified HTLV-I provirus load using the AmpliSensor system, which utilizes fluorescence to measure PCR products. With this method, provirus loads could be measured within 6 hr, and the results obtained correlated well with those obtained by other methods. Samples from 256 blood donors, who were positive for antibodies against HTLV-I, were analyzed, showing that provirus load ranged from less than 0.1% to 56% among carriers. We analyzed the association between provirus load and the biomarkers age and sex and found that it was not influenced by either. Provirus load was better correlated with soluble interleukin-2 receptor (sIL-2R) levels than with antibody titer against the virus. Among 18 blood donors with high provirus load (more than 10%), Southern blotting detected monoclonal integration of HTLV-I in infected cells in 2 cases, both of them showing high sIL-2R levels (more than 900 U/ml). Sequential analyses of provirus load showed stable levels of provirus in the same carriers, suggesting that some factors other than age or sex determined provirus load in infected individuals. Thus, this rapid method is a useful tool for the early detection of adult T-cell leukemia and other HTLV-I-associated diseases.

Adolescent↗

Trends in blood pressure and urinary sodium and potassium excretion in Japan: reinvestigation in the 8th year after the Intersalt Study.

Using the identical protocol of an Intersalt Study previously conducted, we undertook a new study (Intersalt-2) 8 years later. We measured changes in various factors affecting blood pressure (BP) including urinary sodium and potassium excretion in three districts of Japan: Osaka, Tochigi, and Toyama. Also we evaluated the trends in the relationships of those factors to BP. The Intersalt Study revealed that the average sodium excretion of all three study centres was high (particularly in Toyama) while potassium excretion was relatively low. The sodium/potassium ratio was therefore relatively high. The body mass index (BMI) was favourable, but the prevalence of heavy alcohol drinkers was high. Comparing the first to the second study reveals a decrease in sodium excretion in Toyama, although that area still had the highest value of the three study centres. The average potassium excretion increased only in Osaka. Sodium/potassium ratio decreased in all centres. BMI and the prevalence of heavy drinkers among the subjects of both studies were nearly the same. The trend of the relationship of sodium to BP in Osaka changed from negative to positive. In Toyama, it changed from positive to negative. It is thought that this negative relationship might occur in conjunction with a reduction in salt consumption in a population. In conclusion this study reveals that average sodium consumption in Japan remains high while potassium consumption is still low. As a factor in the prevention of hypertension, further efforts to reduce salt consumption and increase potassium intake are still needed.

Adult↗

Stroke incidence and case fatality in Shiga, Japan 1989-1993.

BACKGROUND: This paper describes incidence rates and case-fatality for sub-types of stroke using data collected in Takashima, Shiga, Japan, from 1989 to 1993 and compares these with similar registers in other parts of Japan. METHODS: Registered patients included all residents of the county who experienced a first-ever stroke. Stroke was defined as sudden onset of neurological symptoms which continued for a minimum of 24 hours or led to death. Almost all such patients are hospitalized in this country. Early case fatality was defined as patients who died within 28 days of stroke onset. Diagnosis of stroke type was based on clinical symptoms as well as computed tomography (CT) scans. RESULTS: Age-adjusted incidence rates for stroke per 100,000 population aged 35 years and older were 268.7 for men and 167.5 for women. The age-specific incidence rate of both cerebral infarction and cerebral haemorrhage increased with advancing age. The occurrence of cerebral infarction in men was twice as high as in women. The 28-day case fatality for all sub-types of stroke was 16.1% in men and 15.8% in women. Case fatality for cerebral infarction, cerebral haemorrhage, and subarachnoid haemorrhage was 10.7%, 22.4% and 28.6% respectively. CONCLUSIONS: Takashima County has a moderately high stroke incidence rate and case fatality compared with other similar studies in Japan. The incidence rate of cerebral infarction in men is twice that in women, while other sub-types of stroke showed smaller differences. In order to decrease the incidence of stroke in Japan, greater efforts at primary prevention will be necessary, in particular, it is important to prevent cerebral infarction in men.

Adult↗

Modulation of T-cell responses to a recall antigen in human T-cell leukemia virus type 1-infected individuals.

To determine the mechanism of the purified protein derivative (PPD)-specific hyporesponsiveness in Mycobacterium bovis BCG-vaccinated human T-cell leukemia virus type 1 (HTLV-1)-infected individuals, we examined cytokine production in response to PPD in the following four groups of individuals: (i) HTLV-negative, PPD nonresponders (n = 11; NN); (ii) HTLV-negative, PPD responders (n = 18; NP); (iii) HTLV-positive, PPD nonresponders (n = 15; PN); and (iv) HTLV-positive, PPD responders (n = 15; PP). In vitro stimulation with PPD resulted in both proliferative responses and gamma interferon (IFN-gamma) production in NP and PP (P < 0.02), with minimal proliferation and IFN-gamma production in the NN and PN groups. Further, PPD-specific interleukin 10 (IL-10) production was significantly reduced in the PN group (P < 0.01), while the other groups had comparable levels. Cytokine reconstitution experiments demonstrated that while addition of recombinant IL-12 (rIL-12) plus anti-IL-4 restored PPD-specific responses in the NN group, it had no effect in the PN group. However, addition of rIL-12 resulted in the increased production of IFN-gamma in both nonresponder groups (NN and PN), suggesting that the lack of IFN-gamma production was not responsible for the PPD anergy. We conclude that PPD-specific anergy in HTLV-1-infected individuals appears to be due in part to their inability to respond to rIL-12.

Antigens, Bacterial↗

Changes in body mass index and its relationships to other cardiovascular risk factors among Japanese population: results from the 1980 and 1990 national cardiovascular surveys in Japan.

Few studies have attempted to investigate the changes in body mass index (BMI) and its relationship to other cardiovascular factors in Asian populations, including Japanese. Data from two national cross-sectional surveys on circulatory disorders in 1980 and 1990 in Japan were used in this study. The sample consisted of 10,556 participants in the 1980 survey and 8,385 in the 1990 survey, aged > or = 30 years. The results show that after adjusting for age, smoking, alcohol consumption (ALC) and daily life physical activity (PA), mean BMI increased 0.49 kg/m2 (95% confidence interval: 0.34-0.65) in men aged 30-59 and 0.61 kg/m2 (0.37-0.86) in those aged > or = 60 from 1980 to 1990. In women, however, mean BMI decreased 0.24 kg/m2 (-0.39 0.09) in those aged 30-59 and increased 0.38 kg/m2 (0.12-0.64) in those aged > or = 60. BMI was significantly associated with hypertension, diabetes and hypercholesterolaemia. In both genders, cu-smokers had lower mean BMI than never smokers, while among the cu-smokers, mean BMI was positively associated with the number of cigarettes smoked per day. In men, BMI was positively associated with ALC and negatively associated with PA, while in women, BMI was negatively associated with ALC and positively associated with PA. The results suggest that BMI has significantly increased in men and in elderly women. BMI, even in the Japanese population who are characterized by relative low BMI, is significantly associated with several cardiovascular risk factors.

Adult↗

[Randomized controlled trial for smoking cessation among city office employees].

To evaluate the effect of a smoking cessation program by health professionals, a randomized intervention study was carried out in the Omihachiman city office in 1993. Participants (n = 53), volunteers from current smokers in the city office, were randomly divided into intervention and control groups. The intervention group received intensive education for five months (i.e., the effect of smoking on health, the beneficial aspects of quitting smoking, how to stop smoking and how to deal with the withdrawal symptoms). Group lectures (two times) and individual counseling (three times) were used for health education. After five months, the control group was also given the same advice on smoking cessation. Comparison of smoking cessation rates between the two groups was performed at the end of the intervention period. Follow-up of all participants occurred at six and 12 months post intervention. After the five months of intervention, smoking cessation rate in the intervention group (19.2%) tended to be higher than that in the control group (7.4%), but was not significant (chi 2 = 1.62). Over all smoking cessation rates of all participants (n = 53) at the end of the 10 month intervention was 32.1% and at six months and 1 year after the end of the 10 month intervention were 24.5% and 13.2%, respectively. Comparison of participants who successfully stopped smoking and those who did not, it was revealed that younger age, lower expired air CO concentration (p < 0.01), and attitude for smoking cessation at the beginning were significantly related to smoking cessation. In our study, after five months, smoking cessation rate in the intervention group was about two times that of the control group, although the effectiveness of our smoking cessation program could not be validated due to small sample size. Taking into account the rate of smoking cessation after one year, We believe that programs by health professionals are effective for smoking cessation.

Adult↗

[A case of Hopkins syndrome with onset at puberty].

The patient was a 15-year-old man who developed weakness of left leg 6 days after an acute asthmatic attack. Neurological examination revealed severe muscle weakness and atrophy at L5-S1 level and mild muscle weakness and atrophy at L2-4 level in the left leg. Deep tendon reflexes were normal in the upper limbs and slightly brisk in the lower limbs except for absence of Achilles tendon reflex on the left. His sensation was normal. Needle EMG revealed neurogenic changes in both the left (L2-S1) and right (L2-4) leg muscles. Motor nerve conduction study of the left tibial and peroneal nerves revealed a marked reduction of amplitude and mild reduction of MCV. F-wave was not evoked in either nerves. Sensory nerve conduction study of the left sural nerve was normal. The titers of anti-viral antibodies in the paired sera showed no significant changes in any viruses examined including echovirus, enterovirus, coxsackievirus and poliovirus type 1, 2 and 3. The serum IgE was elevated (1,300 IU/ml) and mite antigen-specific IgE was strongly positive. Spinal cord MRI revealed no abnormality in either thoracic or lumbar spinal cord. This patient was diagnosed as a rare case of Hopkins syndrome with onset at puberty.

Adolescent↗

[A case of motor and sensory polyneuropathy with retinitis pigmentosa and diffuse idiopathic skeletal hyperostosis].

We here report a 53-year-old man who presented with motor and sensory polyneuropathy, retinitis pigmentosa and diffuse idiopathic skeletal hyperostosis (DISH). He had a 15-year history of diabetes mellitus (DM). Visual impairment appeared at 17 years of age. Since age 47, he showed a slowly progressive sensory impairment and muscle weakness of the extremities. On neurological examination, retinitis pigmentosa and severe muscle atrophy, muscle weakness and sensory disturbance of all modalities in the distal portions of all four extremities were observed. Deep tendon reflexes were absent. A plain X-P showed diffuse ossification of the spinal and extraspinal ligaments. The motor nerve conduction velocities were severely reduced and no sensory nerve action potentials were evoked. The CSF examination revealed an increased protein level without pleocytosis. The sural nerve biopsy showed a marked onion bulb formation and a loss of the myelinated nerve fibers, which could not be solely explained by DM. As the phytanic acids levels, beta-lipoprotein, lactate and pyruvate in the sera were within the normal ranges, Refsum disease, Bassen-Kornzweig syndrome and mitochondrial diseases were unlikely in this patient. The presence of demyelinating and axonal polyneuropathy in this patient may have been caused by a common metabolic disturbance which produced both retinitis pigmentosa and DISH.

Diabetes Complications↗

Suppression of skin reactivity to purified protein derivative by hepatitis C virus among HTLV-I carriers in Japan.

In a population endemic for HTLV-I and hepatitis C virus (HCV), HTLV-I infection has been associated with a suppressed cell-mediated immunity measured by anergy to purified protein derivative (PPD). However, the effect of HCV and the impact of coinfection with HTLV-I and HCV have not been previously evaluated. To approach this issue, PPD reactivity was analyzed among 300 study subjects in the community-based Miyazaki Cohort Study. An erythema of <10 mm in diameter 48 hours after subcutaneous injection of the antigen defined PPD anergy. Logistic regression was used to estimate the relative risks. With adjustment for age, gender, and HTLV-I seropositivity, anti-HCV positivity was not independently associated with PPD anergy (odds ratio [OR] = 1.1; 95% confidence interval [CI] = 0.6-1.9). Subjects with both anti-HCV and anti-HTLV-I had a fivefold risk of PPD anergy relative to those free of both infections (OR = 5.2; 95% CI = 1.9-13.8). The risk was nearly threefold among those with anti-HTLV alone (OR = 2.8; 95% CI = 1.4-5.3). Thus, coinfected study subjects were 1.9 times more likely to have PPD anergy compared with those singly infected with HTLV-I (p = .34). HCV infection may slightly increase the risk of PPD anergy among HTLV-I carriers.

Adult↗

Risk factors for adult T-cell leukemia among carriers of human T-lymphotropic virus type I.

The presence of circulating "flower cells" and a low prevalence of antibody to Tax regulatory protein of human T-lymphotropic virus type I (HTLV-I) are characteristics of adult T-cell leukemia (ATL). To examine the predictability of levels of HTLV-I antibodies and of flower cell-like abnormal lymphocytes (Ably) for the risk of ATL among asymptomatic HTLV-I carriers, we prospectively evaluated the levels of viral markers of five HTLV-I carriers who developed ATL and 38 age-, sex-, and screen-matched HTLV-I-positive controls in the Miyazaki Cohort Study. After accounting for matching factors, Ably level was slightly, but not significantly, higher among cases than among controls (P =.13). Anti-HTLV-I (odds ratio [OR] = 1.6 per twofold dilution; 95% confidence interval [CI] 0.94, 3.8) was associated with ATL diagnosis, but antibody to Tax regulatory protein (anti-Tax) was not (OR = 0.78; 95% CI 0.26, 1.7). Anti-Tax level was low for all ATL cases for up to 10 years preceding their diagnosis, independent of the level of anti-HTLV-I titer. HTLV-I carriers with a higher anti-HTLV-I titer and a lower anti-Tax reactivity may be at greatest risk of ATL.

Adult↗

Predictors of level of circulating abnormal lymphocytes among human T-lymphotropic virus type I carriers in Japan.

Human T-lymphotropic virus type I (HTLV-I) carriers often have abnormal lymphocytes (Ably) that resemble malignant cells of adult T-cell leukemia (ATL). To identify predictors of the level of Ably in a longitudinal study of asymptomatic HTLV-I carriers, we analyzed data from 215 subjects (67 men and 148 women) with multiple Ably measurements on blood smears. Ably+ (those having Ably > 0.6% of leukocytes counted on a blood smear at least once) was strongly associated with a high proviral load (OR 8.9; 95% CI 4.1, 19.5). The association among those defined as Ably++ (Ably > 0.6% at all screens or Ably > 1.6% at least once) was higher (19.7; 6.9, 56.1). Ably++ was also significantly associated with male gender (2.8; 1.0, 7.8). Multivariate analysis of Ably level indicates that men with a high proviral load, high anti-HTLV-I titer and low anti-Tax reactivity have the highest Ably level.

Carrier State↗

Intrafamilial transmission of HTLV-I and its association with anti-Tax antibody in an endemic population in Japan.

To assess the relationship of anti-Tax antibody to human T-cell lymphotropic virus type-I (HTLV-I) transmission, the sero-prevalence of HTLV-I was analyzed among married couples and among mother/child (both adults) pairs. HTLV-I seroprevalence was significantly higher among wives with anti-Tax+ than those with anti-Tax- HTLV-I carrier husbands (82.4% vs. 59.5%). However, in the group of wives aged 60 years or older, there was no statistical difference in HTLV-I seropositivity based on the husbands' anti-Tax sero-status. In the group whose wives were less than 60 years old, more anti-Tax sero-positive than sero-negative husbands had high DNA levels (57.1% and 20.0%), whereas in the group of husbands whose wives were aged 60 years or older, the number of anti-Tax sero-positive and sero-negative individuals with high DNA levels was similar. HTLV-I sero-prevalence was significantly higher among the adult men with anti-Tax+ carrier mothers than those with anti-Tax- carrier mothers (52.0% vs. 14.3%). For women, HTLV-I sero-prevalence did not differ significantly according to their mothers' anti-Tax sero-status. Our results suggest that the presence of anti-Tax antibody in HTLV-I carriers is an age-dependent risk factor for male-to-female HTLV-I transmission. Furthermore, the effect of the mother's anti-Tax antibody as a risk factor for vertical HTLV-I transmission could be observed in men even after becoming adults.

Adult↗

Disposition of mirosamicin in honeybee hives.

Disposition of mirosamicin, a macrolide antibiotic, to honeybee adults, larvae, honey and royal jelly in the beehive after in-feed administration to adult bees was studied. Treatment was initiated at the end of July when the availability of natural pollen and nectar was poor. The drug was mixed with pollen-substitute paste and administered to honeybee colonies continuously for a week at a dosage of 200 mg/hive/week. High distributions in adult bees, jelly, larvae and a relatively low distribution in honey, of mirosamicin were observed. One day dosing of microsamin in sucrose syrup, a nectar substitute, resulted in a very high and long lasting residue in honey. Both royal and worker jelly, secreted from the jelly glands of adult bees, are acidic, so that a high distribution of a basic drug, such as mirosamicin, in jelly can be expected. This mechanism was considered to be responsible for a high concentration of mirosamicin in honeybee larvae, the host of Paenibacillus-larvae infection (American foulbrood), as primary larval food is jelly.

Animals↗

Relationship between blood pressure and alcohol consumption on the previous day in Japanese men.

An association has been found between high blood pressure (BP) and the regular consumption of alcohol in epidemiological studies, and a repeated withdrawal reaction to alcohol is considered one of the mechanisms of high BP in drinkers. In this study, we investigated the association between BP and alcohol consumption on the previous day in regular male drinkers. The study participants were 551 men aged 20 to 59 yr who drank alcohol regularly. BP was measured and information on daily alcohol intake was obtained from each participant by a questionnaire, which also asked whether alcohol had been consumed on the day before BP measurement. Age-adjusted BP was compared between participants who had (n=504, 91.6%) and those who had not (n=47, 8.4%) consumed alcohol on the previous day. There were no significant differences between the two groups with regard to BP or body mass index. Even after excluding subjects who were receiving anti-hypertensive drugs, there was still no significant difference in age-adjusted BP between the two groups. Our study found no association between BP and alcohol consumption on the previous day in regular male drinkers, which implies that alcohol withdrawal after 1 d of abstinence cannot explain the high blood pressure found in regular drinkers in this Japanese middle-aged population.

Adult↗

Persistent clonal proliferation of human T-lymphotropic virus type I-infected cells in vivo.

Clonal proliferation of human T-lymphotropic virus type I (HTLV-I)-infected cells has been detected by Southern blot analysis and inverse PCR in patients with adult T-cell leukemia, patients with HTLV-I-associated diseases, and even in asymptomatic carriers. Combining inverse PCR with long PCR, we amplified the genomic DNA regions flanking the integration sites of the HTLV-I provirus to detect clones of infected cells. Inverse long PCR revealed that increased virus load was associated with an increase of both the number of cells in each clone and the number of clones. Clonal proliferations were found in both CD4- and CD8-positive cells in a carrier and a patient with HTLV-I-associated neuropathy/tropical spastic paraparesis. These HTLV-I-infected clones persisted over several years in the same carriers, and, moreover, most of the persistent clones were CD4 positive in a HTLV-I carrier. These findings indicate that HTLV-I infection plays an important role in the clonal expansion of lymphocytes and the prolonged survival of CD4-positive cells in vivo. Surviving T-lymphocytes may be susceptible to genetic changes, leading to the onset of leukemia.

Adult↗

Heterosexual transmission of hepatitis C virus among married couples in southwestern Japan.

The heterosexual transmission of hepatitis C virus (HCV) remains controversial, and data from general populations are scanty. In this cross-sectional study, we assessed the seroprevalence of antibodies to hepatitis C virus (anti-HCV) and the presence and genotype of HCV-RNA among 109 married couples within an endemic, community-based Japanese population. Overall, 25% of the husbands and 32% of the wives had anti-HCV. Spouses with anti-HCV-positive partners were around 2 times more likely to have anti-HCV than spouses with anti-HCV-negative partners (p = 0.01). Of 6 couples in which both spouses had HCV-RNA, however, 3 presented discordant HCV genotypes (type 1b vs. 2b). The couples' anti-HCV concordance status was not significantly influenced by the presence or absence of HCV-RNA among anti-HCV-positive partners (odds ratio [OR]: 0.8 for wives, 0.6 for husbands), nor by the length of marriage, the number of pregnancies or the use of contraceptives. No significant associations with anti-HCV were observed for serum markers of sexually transmitted agents, including human T-lymphotropic virus (OR = 1.1, 95% confidence interval [CI] 0.5-2.3), Treponema pallidum (OR = 0.7; CI 0.1-6.1) and hepatitis B virus (OR = 1.6; CI 0.9-3.0). Our results suggest that the clustering of HCV infection among specific couples within this endemic population may not be attributable to heterosexual transmission. Follow-up studies are necessary to determine the risk of heterosexual transmission of HCV in endemic areas.

Adult↗