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Kokichi Arisawa

Publications and source records attributed to Kokichi Arisawa.

At least 19 recordsLinked to original sources
PubMed2006

Human T-cell lymphotropic virus type-1 infection and risk of cancer: 15.4 year longitudinal study among atomic bomb survivors in Nagasaki, Japan.

The objective of the present study was to investigate the association between human T-lymphotropic virus type-1 (HTLV-1) infection and cancer risk in a longitudinal study. The study population consisted of 2729 atomic bomb survivors in Nagasaki Prefecture, Japan, who had no previous history of cancer at baseline. The baseline survey, including analysis of antibody to HTLV-1, took place during 1985-1987 and follow-up was performed until the end of 2001. There were 553 incident cases of malignant neoplasms during the observation period. After adjustment for sex, age and other variables, HTLV-1 infection was not associated with the risk of developing cancers of all sites, excluding adult T-cell leukemia (rate ratio 1.0, 95% confidence interval [CI] 0.76-1.4), stomach, colon and rectum, lung, female breast or other minor sites, but was associated with increased risk of liver cancer (rate ratio 2.1, 95%CI 1.0-4.6). The point estimate of the rate ratio for thyroid cancer was 3.0, but this was not significantly higher than 1 because of the small number of events (n = 11) and low prevalence of HTLV-1 seropositivity. These findings support the idea that HTLV-1 infection is not associated with an increased general cancer risk. Confounding by hepatitis C virus (HCV) and the interaction between HTLV-1 and HCV may explain the increased risk of liver cancer among HTLV-1 carriers. Further follow-up may be required to determine if HTLV-1 carriers are at increased risk of thyroid cancer.

Female↗
PubMed2006

[Introduction of proteomic approach to environmental medicine].

Recent progress in life science technology and the availability of much information on genes obtained by genome analysis has enabled us to analyze the changes of proteins on a large scale. Sets of proteins are called proteomes, and proteomics is the scientific field of proteome analysis including differential, post translational modification and interaction analyses. Various proteomic techniques, particularly two-dimensional gel electrophoresis (2-DE), mass spectrometry, protein chip methods, and surface plasmon resonance (SPR), are very useful for acquiring proteomes in cells, tissues and body fluid, and for analyzing interactions between a protein and other biofactors including proteins. A proteomic approach is also useful for determining biomarkers of diseases and key proteins involved in various stages of metabolism such as differentiation, cell cycle and apoptosis. Environmental pollutants including endocrine disruptors inhibit activities of various organs in wild animals and humans. Proteomic approaches could be very useful tools for elucidating the mechanisms of damage caused by environmental pollutants. In this review, we describe the application of a proteomic approach to the field of environmental medicine.

Animals↗
PubMed2005

Multiprefectural spread of gastroenteritis outbreaks attributable to a single genogroup II norovirus strain from a tourist restaurant in Nagasaki, Japan.

A series of gastroenteritis outbreaks caused by noroviruses (NVs) among tourist groups from several prefectures was associated with eating a lunch prepared by a restaurant in Nagasaki City, Japan, on 18 and 19 November 2003. A retrospective cohort study was performed to estimate the magnitude of the outbreak and identify the source of infection. Epidemiological information was obtained through the local public health centers in the areas where the illness occurred. Stool and vomit specimens and food and environmental samples were analyzed by reverse transcription-PCR with genogroup-specific primers. Positive samples were sequenced and analyzed phylogenetically. Of 1,492 tourists who ate a lunch prepared by the restaurant during the 2-day period, 660 (44.2%) developed illness, with an average incubation time of 31.2 h. Whereas NVs were not detected in any food samples, identical sequences most closely related to the Mexico genotype of genogroup II NV were found in specimens from case patients, restaurant staff, and the kitchen table. Food handlers were concluded to be the source of the outbreak as a result of the contamination of several meals. The series of outbreaks described here exemplifies the role of tourism as a contemporary way to distribute a single infectious agent to multiple and geographically remote areas.

Adolescent↗
PubMed2005

Background exposure to PCDDs/PCDFs/PCBs and its potential health effects: a review of epidemiologic studies.

Here we review epidemiologic studies dealing with the dietary intake and the body burden of polychlorinated dibenzo-p-dioxins (PCDDs)/polychlorinated dibenzo-furans (PCDFs)/ polychlorinated biphenyls (PCBs) in the general population, and potential adverse health effects of these substances, especially on the risk of diabetes mellitus and endometriosis, and on thyroid function and the neurodevelopment of infants. The mean or median intake of dioxin-related compounds among the general populations of various countries is lower than the maximum tolerable daily intake (TDI) set by the WHO in 1998 (4pg TEQ/kg/day). However, there have been few reports on the distribution of intake and the proportion of subjects whose exposure levels exceed the maximum TDL. At present, it remains unclear whether background exposure to dioxin-related compounds is associated with increased risk of diabetes (because of lack of longitudinal studies), endometriosis (because of lack of studies with sufficient statistical power), or altered thyroid function (because of inconsistent results on humans). Consistent results have been reported for the association between exposure to background levels of PCBs/dioxins, especially trans-placental PCBs, and defective neurodevelopment of infants in the U.S. and Europe. Thus, efforts should be made to further decrease the body burden among women of reproductive age by reducing the release of PCDDs/PCDFs/PCBs into the environment.

Benzofurans↗
PubMed2005

Relationship between the type of urinary incontinence and falls among frail elderly women in Japan.

Urinary incontinence and falls are serious problem among elderly people, because of restriction of the Activities of Daily Living (ADL) and Quality of Life. Previous studies have examined the association between urinary incontinence and falls. However, results have been inconsistent. In Japan, with the rapid aging of the society, the number of elderly women who have urinary incontinence and are at risk of falling is increasing. We investigated the relationship between type of urinary incontinence and risk of falls among elderly users of day-care services in a long-term care system. Our study population comprised 118 ambulatory women. At baseline, we evaluated incontinent status, lower extremity muscle strength, balance ability, ADL, and Instrumental ADL. We asked subjects about number of falls every 4 months during a year. In univariate analysis, lower extremity muscle strength (p = 0.001) and mixed incontinence (p = 0.050) differed significantly according to the fall status. Stress and urge incontinence were not significantly associated with falls. In logistic regression analysis, subjects who had mixed incontinence were 3.05 (95% confidence interval 1.01-10.2) times more likely to fall than those without. These results suggest that mixed incontinence have independent associations with falls. Incontinent status should be considered to prevent falls among elderly persons who are partially dependent and need support.

Accidental Falls↗
PubMed2004

Abnormal folic acid-homocysteine metabolism as maternal risk factors for Down syndrome in Japan.

BACKGROUND: Japan has been considered as "a folate sufficient area", since traditional Japanese food contains an adequate amount of folic acid. However, the recent westernized food style of young Japanese mothers may affect the intake of folic acid among them. This food style may contribute to the occurrence of Down syndrome, which has proved to be linked to abnormal folate and homocysteine metabolisms. AIM OF THE STUDY: To preliminarily evaluate the levels of folic acid,homocysteine and other relevant factors which are associated with folate metabolism, among Japanese women who had pregnancies affected by Down syndrome. METHODS: Blood samples from 31 women who had pregnancies affected by Down syndrome (DS) were obtained. 60 age-matched control blood samples were also obtained from mothers who had not experienced miscarriages or abnormal pregnancies (CONT). Plasma homocysteine and serum folic acid, vitamin B12, and B6 were measured and compared between DS and CONT. Furthermore, the frequency of MTHFR polymorphism (C677T) was also investigated. RESULTS: Plasma levels of homocysteine were significantly increased in DS mothers (p = 0.004). In contrast, serum levels of folic acid were significantly decreased in DS mothers (p = 0.0001). There were no significant differences in the vitamin B12 and B6 levels between DS and CONT. Also, the frequency of 5,10-methylenetetrahydrofolate reductase gene (MTHFR) homozygous polymorphism showed no differences between DS and CONT. CONCLUSION: Different levels of serum folic acid and plasma homocysteine between both groups may contribute to the occurrence of Down syndrome even in Japan. Although there was no significant difference in the frequency of MTHFR polymorphism between the groups, probably because of an inadequate number of samples, further studies may contribute to the understanding of the occurrence of Down syndrome in Japan.

Adult↗
PubMed2004

An outbreak of gastroenteritis during school trip caused by serotype G2 group A rotavirus.

Between May14 and 18, 2001, there was an outbreak of acute gastroenteritis involving 45 school children out of a total of 107 (aged 11-12 years) attending a 3-day school trip. The epidemic curve characterized by a rapid onset and decline with a single peak incidence over a 5-day period resembled the pattern typical of a food-borne gastroenteritis outbreak. Epidemiological and virological investigations concluded, however, that this outbreak was caused by a single strain of serotype G2 group A rotavirus spreading to schoolmates from the primary case-pupil who had already been ill at the start of the trip. Efficient person-to-person transmission was likely to have occurred due to prolonged and close contacts under the conditions typical of such school trips. This study emphasizes the importance of including group A rotavirus infection as a possible cause of gastroenteritis outbreaks even in older children and adults.

Child↗
PubMed2004

Estimation of annual incidence, age-specific incidence rate, and cumulative risk of rotavirus gastroenteritis among children in Japan.

Rotavirus gastroenteritis is a common childhood infection, but the exact morbidity of the disease is not well described in Japan. We aimed at estimating morbidity measures to determine the magnitude of rotavirus gastroenteritis. An estimate for acute infectious gastroenteritis of all causes, to which rotavirus gastroenteritis belongs, has been available since the enactment in 1999 of the Law concerning the Prevention of Infectious Diseases and Medical Care of Patients with Infectious Diseases. Using this estimate and another estimate for the detection proportion of rotavirus among outpatients with acute infectious gastroenteritis, we calculated the annual incidence, the age-specific annual incidence rate, and the cumulative risk by the age of 6 years for rotavirus gastroenteritis. The latter estimate was obtained by a meta-analysis of four independent studies previously performed in Japan. According to our estimates, approximately 800,000 children in Japan under the age of 6 years visit pediatric practices or the outpatient department of hospitals because of rotavirus gastroenteritis at a rate of 11 cases/100 persons/year, and one in two children will visit pediatricians before they go to primary school. Such pediatrician visits most frequently occur at the age of 1 year (27 cases/100 persons/year). Thus, the magnitude of the burden of rotavirus disease among Japanese children is substantial.

Age Distribution↗
PubMed2003

The des-gamma-carboxy prothrombin index is a new prognostic indicator for hepatocellular carcinoma.

BACKGROUND: Des-gamma-carboxy prothrombin (DCP) has been reported to be an important prognostic factor in patients with hepatocellular carcinoma (HCC). Recently, a monoclonal antibody, 19B7, which recognizes the Gla domain of DCP, has been identified. The 19B7 antibody recognizes an epitope different from that recognized by MU-3, which is another antibody against DCP. In this study, the authors investigated the measurement of DCP using the antibodies MU-3 and 19B7, respectively, as a prognostic factor for patients with HCC who had solitary, small tumors and or Child Stage A HCC. METHODS: One hundred four patients with HCC who had solitary, small tumors or Child Stage A tumors were enrolled in the study between 1991 and 2001. All patients were treated and were followed for a mean of 3.2 years. The authors analyzed the correlation between the DCP Index (DCP measured by MU-3 and DCP measured by 19B7) and patient prognosis. The patients were classified into 3 groups based on their DCP Index: 1) DCP negative (DCP < 40 milli arbitrary unit (mAU)/mL)); 2) low DCP Index (DCP > or = 40 mAU/mL; MU-3:19B7 ratio, < 3.0; and 3) high DCP Index (DCP > or = 40 mAU/mL; MU-3:19B7 ratio, > or = 3.0). RESULTS: The survival rate for patients in the high DCP Index group was lower compared with the survival rate for patients in the DCP-negative group and was significantly lower compared with the survival rate for patients in the low DCP Index group. In a univariate Cox proportional hazards model, the positive factors were high DCP Index and low DCP Index. Among the positive predictive factors that were analyzed using a multivariate Cox proportional hazards model were age (hazard ratio, 3.27; P = 0.006), low DCP Index (hazard ratio, 2.87; P = 0.012), and high DCP Index (hazard ratio, 12.3; P < 0.0001). CONCLUSIONS: The prognosis of patients who had a high DCP Index score was poorer compared with patients who had a low DCP Index score and patients who were classified as DCP negative. The authors concluded that the DCP Index is a prognostic indicator for patients with HCC.

Aged↗
PubMed2003

Lower-extremity muscle forces measured by a hand-held dynamometer and the risk of falls among day-care users in Japan: using multinomial logistic regression analysis.

PURPOSE: To assess the relationship between the lower extremity muscle forces and risk of falls among the elderly who were using day-care services in the long-term care insurance system. METHOD: The study population comprised 96 women aged 69 - 91 years. At baseline, we assessed ADL, functional capacity, isometric muscle forces of knee extension and ankle dorsiflexion obtained with a hand-held dynamometer. After 1 year, we asked subjects about falls during the follow up period. RESULTS: In univariate analysis, only the knee extensor strength (p = 0.003) and ankle dorsiflexor strength (p = 0.02) differed significantly according to the fall status. After adjustment for age using multinomial logistic regression analysis, the weak quadriceps group was 7.50 times more likely than the strong group to fall once (p = 0.02), and 5.00 times more likely to fall twice or more (p = 0.02). The weakest ankle dorsiflexor group was 5.09 times more likely than the strongest group to fall twice or more (p = 0.05). CONCLUSIONS: Our results indicated that the forces of knee extensor and ankle dorsiflexor were strongly associated with falls among day-care users. Physiotherapy should focus on the lower-extremity muscle strength to prevent falls and deterioration of physical ability among elderly persons who are partially dependent and need support.

Accidental Falls↗
PubMed2003

Neonatal behavioral assessment scale as a predictor of later developmental disabilities of low birth-weight and/or premature infants.

The purpose of this study was to evaluate the usefulness of the Neonatal Behavioral Assessment Scale (NBAS) as a tool to assess the risk of later developmental disabilities. The study subjects were 209 low birth-weight and/or premature infants admitted to the NICU at the Nagasaki University Hospital, Nagasaki, Japan. These infants were examined using the NBAS at 36-38 (NBAS36), 40-42 (NBAS40) and 44-46 weeks (NBAS44) of postmenstrual age, and their developmental outcome was measured using standardized assessments at 5 years of age. Based on the results of diagnosis at 5 years of age, subjects were classified into three groups: Normal, Mild Disability and Severe Disability groups. Multinomial logistic regression analysis showed that lower Motor cluster scores for all assessment periods and lower Orientation cluster scores in the NBAS40 and NBAS44 were significantly associated with an increased risk of both Mild and Severe Disability. Also, the Range of State cluster scores for the NBAS44 were significantly related to the risk of Mild Disability, and the Reflexes cluster scores in the NBAS40 and NBAS44 were the best predictor of Severe Disability. In outcome prediction using the estimated regression coefficients, 94-97% of the subjects in the Normal group, 50-78% in the Mild Disability group and 71-85% in the Severe Disability group were correctly classified. The NBAS could help clinicians to develop a management protocol for infants at risk for developmental disabilities as well as to identify neonates at risk of developmental disabilities.

Aging↗
PubMed2003

Human T-lymphotropic virus type-I infection, survival and cancer risk in southwestern Japan: a prospective cohort study.

OBJECTIVES: This study prospectively evaluated the associations of human T-lymphotropic virus type-I (HTLV-I) infection with survival and cancer incidence. METHODS: The study base comprised 4297 adults (aged 40-69 years in 1993) who had either visited the outpatient clinic or who had received annual health check-ups at the A Hospital, Nagasaki, Japan, between 1985 and 1992 (HTLV-I seropositivity = 24.7%). During the follow-up period (1993-1999 or 2000), 290 deaths and 261 cases of malignant neoplasms occurred, including ten deaths and six incident cases of adult T-cell leukemia/lymphoma (ATL). RESULTS: After adjustment for gender, age and other covariates, HTLV-I seropositivity was associated with an increased mortality from all-causes excluding ATL (rate ratio, RR = 1.3, 95% confidence interval, CI = 1.0-1.7), all non-neoplastic diseases (RR = 1.5, 95% CI = 1.0-2.3) and heart diseases. HTLV-I infection was not found to be associated with an increased risk of developing total cancers other than ATL (RR = 0.98, 95% CI = 0.74-1.3), colorectal cancers, liver cancer or lung cancer, but was associated with a reduced risk of gastric cancer (RR = 0.42, 95% CI = 0.17-0.99). CONCLUSIONS: HTLV-I infection is associated with increased mortality from all-causes excluding ATL and all non-neoplastic diseases. HTLV-I carriers may not be at increased general cancer risk, but at reduced risk of gastric cancer.

Aged↗
PubMed2003

Neonatal behavioral characteristics and later behavioral problems.

The purposes of this study were (1) to evaluate the usefulness of the Neonatal Behavioral Assessment Scale (NBAS) as a tool to assess the risk of later behavioral problems, (2) to analyze the relationship between neonatal behavioral characteristics and behavioral problems in childhood. Subjects were 77 very-low-birth-weight infants admitted to the NICU at the Nagasaki University Hospital, Nagasaki, Japan. The results suggest that behavioral characteristics such as poor motor performance, poor state regulation, and poor interaction ability in the neonatal period are risk factors for behavioral problems in childhood. The NBAS could help clinicians to identify neonates at risk of later behavioral problems.

Child↗
PubMed2002

Fish intake, plasma omega-3 polyunsaturated fatty acids, and polychlorinated dibenzo-p-dioxins/polychlorinated dibenzo-furans and co-planar polychlorinated biphenyls in the blood of the Japanese population.

OBJECTIVES: To evaluate background exposure levels and determinants of the individual variations in the exposure to dioxins in Japan. METHODS: A cross-sectional study was performed on 131 men and 122 women (aged 20-76 years), who resided in five prefectures of Japan and had no occupational exposure to dioxins. Seven polychlorinated dibenzo-p-dioxins (PCDDs), ten polychlorinated dibenzo-furans (PCDFs) and 12 polychlorinated biphenyls (PCBs), which are assigned a toxicity equivalent factor, were determined in fasting blood. Biochemical analysis of plasma and a questionnaire survey on life-style, including dietary habit, were also performed. Factors associated with the levels of dioxin-related compounds in blood were evaluated by multiple linear regression. RESULTS: The median of total toxicity equivalents (TEQs) in men and women was 17 and 16 pg TEQ/g lipid, respectively, with no gender difference. After adjustment for age and other covariates, plasma concentrations of eicosapentaenoic acid, a biomarker of fish intake, were found to be positively associated with blood levels of total dioxin, PCDDs, PCDFs and PCBs, all of which were expressed on a TEQ basis (P<0.01). The frequency of intake of coastal fish, such as horse mackerel, mackerel and sardine, was also associated with TEQ-based concentrations of PCDFs (P=0.03) and PCBs (P=0.08). The intake of raw fish was positively related to total dioxins (P=0.06) and PCBs (P=0.03). CONCLUSIONS: The level of intake of marine fish, especially raw fish and coastal varieties, may be associated with increased blood levels of dioxin-related compounds among the population. Despite high fish consumption in Japan, the body burden of dioxins in the population was not found to be higher than that in western countries.

Adult↗
PubMed2002

Impact of aging on the development of hepatocellular carcinoma in patients with posttransfusion chronic hepatitis C.

BACKGROUND: Hepatitis C virus (HCV) infection is a heterogeneous disease, the natural history of which remains controversial. There is solid evidence that chronic HCV infection is responsible for the occurrence of hepatocellular carcinoma (HCC). The aim of the current cohort study was to determine the rate of the development of HCC from the time of primary HCV infection and to assess the risk factors for the development of HCC in chronic posttransfusion hepatitis C patients. METHODS: Four hundred sixty-nine patients with clinically compensated HCV, who had undergone a single blood transfusion comprised the current study cohort. Patients with other risk factors for chronic liver disease were excluded. All patients were referred to the liver center at the National Nagasaki Medical Center between December 1980 and December 1998 and were followed prospectively until the end of the analysis (June 2000). RESULTS: Follow-up data were obtained for 445 patients. The mean duration from HCV infection to the end of the observation was 28 years. Fifty-two patients (11.1%) progressed to HCC. The mean duration from the time of blood transfusion to the diagnosis of HCC was 31 years. Multivariate Cox regression analyses revealed age, fibrosis, duration from HCV infection to study entry, and alcohol consumption to be the independent factors affecting the development of HCC. The risk of developing HCC in patients age > or = 56 years was increased 7.8-fold compared with that in patients age < 56 years. The mean age of patients at the time of HCC diagnosis was 65 years (range, 58-79 years). CONCLUSIONS: At the time of diagnosis, 92% of the 52 HCC patients were age > 60 years and 38 of the HCC patients (73%) were in their 60s. There was a significantly negative correlation between the duration from HCV infection to the development of HCC and the age of the patient at the time of infection (correlation coefficient = 0.702; P < 0.0001; Y = 61.1-0.82X), indicating that the age of patients, rather than the duration of HCV infection, is more significant for HCC development in patients with posttransfusion HCV. Moreover, these data may contribute to the design of an optimal follow-up schedule for patients with posttransfusion HCV.

Adult↗
PubMed2002

Increased expression of sialyl Lewis(x) antigen as a prognostic factor in patients with stage 0, I, and II gastric cancer.

Immunohistochemically detected expression of sialyl Lewis(x) (Le(x)) antigen was analyzed in 101 stage 0-II gastric cancers to clarify its prognostic value after curative gastrectomy. Patients with a high-expression of sialyl Le(x) antigen within their tumors had shorter disease-specific intervals than those with negative- or low-expressing tumors (P<0.0001). This difference was noted particularly in stage I-B or II disease. Multivariate Cox's regression analysis revealed sialyl Le(x) antigen expression to be an independent predictor of disease-specific survival (Hazard ratio=9.10). In conclusion, the increased expression of sialyl Le(x) antigen may serve as a prognostic factor after curative surgery for stages 0-II gastric cancer.

Humans↗
PubMed2002

Geographic distribution of the incidence of adult T-cell leukemia/lymphoma and other malignancies in nagasaki prefecture, Japan.

BACKGROUND: It remains unclear whether human T-cell lymphotropic virus type-I (HTLV-I) infection is associated with an increased risk of malignancies other than adult T-cell leukemia/lymphoma. METHODS: The authors investigated the geographic distribution of the incidence of adult T-cell leukemia/lymphoma and other malignancies in Nagasaki Prefecture, Japan, where HTLV-I is endemic. The world age-standardized incidence rates of adult T-cell leukemia/lymphoma and five cancers of other sites were calculated in 15 areas, using the data from the Nagasaki Prefectural Cancer Registry (1985-97). RESULTS: The incidence of adult T-cell leukemia/lymphoma was found to be positively correlated with that of biliary tract cancer in men (person-years-weighted r = 0.49, P = 0.06) and liver cancer in women (r = 0.56, P = 0.03), but not with cancer of the stomach, lung or cervix uteri. CONCLUSIONS: The results may not support the hypothesis that HTLV-I infection is strongly associated with an increased risk of cancer of the stomach, lung or cervix uteri. The association between HTLV-I infection and cancer of the biliary tract and the possible interaction between hepatitis C virus and HTLV-I in the development of liver cancer should be evaluated by prospective cohort studies.

Adult↗