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Biomedical subjects

T Hirohata

Publications and source records attributed to T Hirohata.

At least 55 records · Page 3Linked to original sources
PubMed1994

Cancer mortality in low radon spa area.

Recently lower mortality for cancers of all sites was reported among inhabitants in the Misasa spa area, where there is a high radon background. To clarify the effects of radon exposure on cancer mortality, the effects of a hot spring itself on cancer mortality was investigated in the Beppu spa area, which has only a low radon background, and adjacent control areas. For females, the mortalities for cancers of all sites, liver and lung were higher in Beppu than those for all Japan on the basis of the standardized mortality ratio (SMR), while the SMR for all cancers was lower in adjacent areas. For the male inhabitants in both areas the cancer mortalities of all sites were not significantly different from those of all Japan. When we directly compared the most typical spa areas in Beppu and an adjacent control area, a Poisson regression analysis did not show that the relative risk of dying from cancer of all sites was decreased in the spa areas. These results are thus consistent with the view that the lower cancer mortality in the Misasa spa area might be related to exposure to low levels of radon.

Adult↗
PubMed1994

[A role of aryl hydrocarbon hydroxylase inducibility in susceptibility to lung carcinogenesis].

Lung cancer mortality has been increasing rapidly in recent years in Japan and is expected to exceed that of stomach cancer in male Japanese in the near future. Although chronic inhalation of cigarette smoke is a major risk factor for the development of lung cancer, it seems important to examine genetic susceptibility to the disease as well. Aryl hydrocarbon hydroxylase (AHH), a drug-metabolism enzyme, is useful in determining the individual differences in genetic susceptibility to lung carcinogenesis. AHH is a microsomal membrane-bound monooxygenase system located in most tissues of the body. In mice, AHH inducibility is under the control of the Ah locus and certain inbred strains of mice are susceptible to AHH induction by 3-methylcholanthrene treatment (Ah responsive strains), while other strains are not (Ah non-responsive strains). A strong correlation was observed between AHH inducibility and tumor incidence in mice. Since AHH is also responsible for the activation to carcinogens of benzo (a)pyrene and other aromatic hydrocarbons in cigarette smoke, it may also be important in humans in the causation of lung cancer. Kellermann et al. investigated the genetics of AHH in a human population and reported that the inducibility of this enzyme was controlled by a single gene locus with 2 dominant alleles. They classified humans as having low, intermediate, or high inducibility of AHH. In addition, they reported a significant positive correlation between the extent of inducibility and susceptibility to lung cancer. Their claim, however, has been both supported and refuted by subsequent investigators. Recently, a close association between development of lung cancer and three polymorphisms of CYP1A1 caused by the presence or absence of one MspI site in the 3'-flanking region, namely, a predominant homozygote pattern (A), a heterozygote pattern (B) and a homozygous rare allele pattern (C), has been reported. The relationship between AHH inducibility and polymorphisms of CYP1A1 had not been investigated previously. Our study indicated that the genotype of C, very frequent in Kreyberg type I, was closely related to high AHH inducibility. Thus, the relationship between AHH inducibility and lung cancer, suggested by Kellermann et al., is supported by our study. Further studies will be needed to confirm the present results. Identification of smokers who have genetically high susceptibility to lung cancer (pattern C), may become important for the prevention of lung cancer.

Animals↗
PubMed1994

Reproducibility of dietary and other data from a self-administered questionnaire.

This study examined the reproducibility of information obtained from a questionnaire covering dietary and other information by comparing the answers to the questionnaires with answers to the same questions one year later. Answers from 191 men and 220 women, aged 40 to 65, in Fukuoka prefecture, Japan were compared. The surveys were conducted in November 1989 and November 1990. In the second survey, 97.2% of the first respondents answered. The concordance between the two responses was high, and the differences between the mean intakes from the two surveys were within 5% for 7 food items and within 15% for 14 food items among the 20 items about which the respondents were asked. The intraclass correlation coefficients varied from 0.30 for eggs to 0.62 for milk, with 16 items greater than 0.4. The differences in reproducibility between the sexes and two age categories were not significant. Close values also were obtained for the estimated consumption of salt. A substantially high reproducibility was observed on items regarding drinking and smoking; most of the kappa statistics and the intraclass correlation coefficients were between 0.5 and 0.9. The above reproducibility on individual food items was comparable to or better than those reported from other studies. The results of the present study thus indicate that the self-administered semiquantitative food intake questionnaire used for our cross-sectional study is useful for epidemiologic studies to assess the association between diet and various diseases. In particular, the present questionnaire is highly dependable regarding the overall group intake of foods.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Epidemiology of gallbladder polyps: an ultrasonographic study of male self-defense officials in Japan.

The prevalence and risk factors of gallbladder polyps diagnosed by ultrasonography were investigated in 2739 male self-defense officials who received a retirement health examination at the Self-Defense Forces Fukuoka Hospital, Japan, between October 1986 and December 1990. Excluding 38 men whose gallbladder had been removed previously, 143 men were found to have gallbladder polyps. The overall prevalence of gallbladder polyps was 5.3%. The relation between gallbladder polyps and smoking, alcohol use, body mass index, glucose tolerance, and serum lipids was examined in 137 men with stoneless polyps and 2495 normal subjects. Whereas smoking tended to be inversely associated with gallbladder polyps, none of the other lifestyle and clinical variables were related to this condition. Thus the reported risk factors of gallstones had no relation to gallbladder polyps.

Alcohol Drinking↗
PubMed1994

[Selective effectiveness of galactose-containing liposome IL-2 on liver lymphocytes].

We have performed immunochemical intraarterial infusion immunochemotherapy containing IL-2, mitomycin C and 5-FU as the main active ingredient for metastatic liver tumor and obtained favorable results. However, we are obliged to perform intra-hepatic arterial infusion once or twice a week, because of the short half-life of IL-2. Thus, we are using a drug delivery system to activate lymphocytes of the liver. We noticed many galactose-receptors in the liver and prepared galactose-containing liposome preparations using various carriers/bases. As a result, galactose-containing liposome preparations showed the highest accumulation and the highest localized enhancing effect on the antitumor activity of lymphocytes in the liver sites.

Animals↗
PubMed1994

[Oral complication of sublabial transsphenoidal approach and advantage of endonasal transsphenoidal approach].

In order to know the exact incidence of oral complications due to the sublabial transsphenoidal approach, the authors meticulously heard the complaints of 46 patients, who had undergone the approach more than 3 months before. The incidence of the patients who had one or more complaints concerning the oral region was 52.2%. Dysesthesia of the upper lip was most frequent (37%), followed by upper lip pain (17.4%). These complaints were more marked in two patients who had undergone operations using the sublabial approach twice. Among the nine patients with dentures, the dentures had to be remade in three patients because of gigival atrophy several months after the use of the sublabial approach. With a view to overcoming these complications, the authors adapted the endonasal transsphenoidal approach in 13 patients. There was no inconvenience during surgery while this approach was being used, and there were no postoperative oral complications. Among three patients using dentures, there were none who needed remodeling of their dentures. In nine patients, the tension reducing incision was made in the bottom of the columella, which caused no cosmetic problem. Furthermore, the time consumed for approaching the sphenoid sinus was less than that required when using the sublabial approach. In conclusion, the following type of patient is believed to be an appropriate candidate for endonasal approach. A patient who has a relatively smaller sellar lesion and 1) An acromegalic patient whose nostril is relatively large, 2) An elderly patient using dentures, 3) A patient who has undergone previous transsphenoidal surgery, or 4) A patient whose columellar crease is hidden.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenoma↗
PubMed1993

Association of alcohol intake, cigarette smoking, and occupational status with the risk of idiopathic osteonecrosis of the femoral head.

To investigate the association of alcohol intake, cigarette smoking, occupation, and other factors with the development of idiopathic osteonecrosis of the femoral head, a nationwide multicenter case-control study was conducted in Japan during 1988-1990, comparing 118 cases with no history of systemic corticosteroid use with 236 controls matched for sex, age, ethnicity, clinic, and date of initial examination. The risks of developing femoral head necrosis associated with potential risk factors were estimated by adjusted relative odds obtained by a conditional logistic regression model. The elevated relative odds were observed for occasional drinkers (relative odds = 3.2, 95% confidence interval 1.1-9.2) and regular drinkers (relative odds = 13.1, 95% confidence interval 4.1-42.5) with a significant dose-response relation (p < 0.001). For current drinkers, the relative odds were 2.8, 9.4, and 14.8 for < 320, 320-799, and > or = 800 g/week of ethanol intake, respectively. An increased risk was found for current smokers (relative odds = 4.7, 95% confidence interval 1.5-14.5), but a linear increasing trend in the cumulative effect of smoking was not evident at 20 pack-years or over. A weak but significant dose-response relation was observed for daily occupational energy consumption (p < 0.05). The present study confirmed the strong association of alcohol intake and positive association of cigarette smoking and suggested the role of heavy physical work.

Adult↗
PubMed1993

A successful liver metastasis model in mice with neuraminidase treated colon 26.

The aim of this study was to establish a reproducible and quantitative liver metastasis model in mice. The in vitro colon 26 (C-26) cultured cell line was initially taken from an in vivo transplantable C-26 adenocarcinoma tumor mass using the standard enzymatic treatments, collagenase and DNAse. In vitro cultured cells x 10(4) were introduced into the portal vein of syngeneic BALB/c mice to induce liver metastases and, 3 weeks later metastatic foci were found in approximately 50% to 70% of the mice. In contrast, C-26 cells desialylated by neuraminidase (Nase) treatment greatly increased the incidence of hepatic metastases with countable hepatic colonies being found in all mice (100%). This result seems to be related to the liver-characteristic D-galactose receptors, since pre-injection with an excess amount of galactocerebroside completely prevented tumor colonization in the liver. Thus, although we cannot disregard the involvement of other adhesion molecules in this system as yet, our experimental model may become a useful tool for the analysis of hepatic metastases from colon cancer in the future.

Animals↗
PubMed1993

Association between blood polychlorinated biphenyl concentration and serum triglyceride level in chronic "Yusho" (polychlorinated biphenyl poisoning) patients.

The association between blood polychlorinated biphenyl (PCB) concentration and serum triglyceride level was investigated in 259 "Yusho" patients (PCB poisoning) who underwent health examinations for Yusho in 1988. Geometric means of PCB and triglyceride were 3.84 ppb (95% confidence interval: 3.54-4.17) and 114.3 mg/dl (106.6-122.6), respectively. Both correlation and multiple regression analyses showed a weak but statistically significant correlation between these two variables. The mean triglyceride level adjusted for age and sex was then calculated for comparison among four PCB levels, using analysis of covariance. This indicated a progressive increase with increasing PCB: 98.36, 117.78, 117.84, and 127.65 mg/dl at < 2.7, 2.7+, 4.1+, and 6.1+ ppb, respectively (F = 2.01, P = 0.113). Comparing PCB levels, the difference in adjusted mean triglyceride levels was marginally significant between the first and second (P = 0.088), and the first and third quartiles (P = 0.066), and reached significance between the first and fourth quartiles (P = 0.021). Thus, a weak but significant association between blood PCB and serum triglyceride was observed in the patients 20 years after exposure, although their blood PCB and serum triglyceride were relatively close to the normal levels.

Adult↗
PubMed1993

In vivo effect of 7,8-benzoflavone on aryl hydrocarbon hydroxylase activity of mouse liver microsomes.

In vivo administration of 3-methylcholanthrene (MC) and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) produced much higher hepatic microsomal aryl hydrocarbon hydroxylase (AHH) induction than 7,8-benzoflavone (7,8-BF) in both aromatic hydrocarbon (Ah)-responsive and nonresponsive strains of mice. Simultaneous treatment or pre-treatment with 7,8-BF produced an inhibitory effect on AHH induction by MC or TCDD (i.e., the degrees of the inhibition, with TCDD, were 28% in the Ah-responsive strain C57BL/6N (C57) mice and 45% in the nonresponsive strain DDD;Qdj (DDD) mice). However, posttreatment with 7,8-BF was inclined to promote the induction of AHH by MC or TCDD (i.e., the degrees of the enhancement, with MC, were 15% in C57 mice and 45% in DDD mice). These results may suggest that the inhibitory effect of 7,8-BF in vivo is limited not to the combination of AHH inducer (MC or TCDD) but to its application of timing or Ah responsiveness.

Animals↗
PubMed1993

Serum lipids and gallstone disease. A study of self-defense officials in Japan.

Based on screening ultrasonography of the gallbladder in 2756 men who received a retirement health examination at the Self-Defense Forces Fukuoka Hospital, Japan, during the period of 1986 to 1990, we compared serum lipid levels among 61 men with gallstones, 38 who had the gallbladder removed previously, and 2494 with a normal gallbladder. In univariate analysis, men having gallstones and those who had had a cholecystectomy had lower concentrations of total and low-density-lipoprotein (LDL) cholesterol than did control subjects, although the differences were not statistically significant. After adjustment for body mass index, smoking, alcohol use, and glucose tolerance, inverse associations of cholecystectomy with total and LDL cholesterol levels were more pronounced and statistically significant. There was no appreciable difference in high-density-lipoprotein (HDL) cholesterol and triglycerides between control subjects and men either with gallstones or after cholecystectomy. The present study did not support a positive relation between gallstones and serum triglyceride levels and an inverse one to HDL cholesterol, which have been reported elsewhere. The findings on total and LDL cholesterol are consistent with some, but not all recent studies.

Cholecystectomy↗
PubMed1993

Enhanced activity against syngeneic murine tumors by intrasplenic injection of recombinant interleukin-2 (IL-2) and interleukin-1 (IL-1).

The antitumor activity of Interleukin-1 (IL-1), was assessed against the murine adenocarcinoma colon 26 tumor model in combination with Interleukin-2 (IL-2). Colon 26 tumor cells were inoculated on the back of syngeneic BALB/c mice. Fourteen days after inoculation, when the tumor nodule reached approximately 10 mm in diameter, tumor nodules were resected and Hank's solution, IL-2, IL-1, or IL-2 plus IL-1 were injected directly into the mouse spleen. One week after treatment, potent natural killer (NK) and enhanced lymphokine activated killer (LAK) cell activities were seen in the splenocytes treated by the combination of IL-2 plus IL-1. Furthermore the combination treatment by IL-2 plus IL-1 resulted in a significantly prolonged survival. Phenotypic analysis showed an increased number of percent positive cells expressing asialo GM 1 and IL-2 receptor after treatment with IL-2 plus IL-1. A possible role of IL-1 in augmentation of IL-2 dependent antitumor activity in vivo is discussed.

Adenocarcinoma↗
PubMed1993

[Laboratory findings in the medical examination of chronic "Yusho" (PCB poisoning) patients: with special reference to blood PCB and serum triglyceride].

Associations of blood PCB concentration with serum levels of triglyceride, gamma-GTP, total-, and conjugated-bilirubin were investigated in "Yusho" patients twenty years after outbreak, using the information obtained from the medical examinations in 1988 and 1989. Study subjects were 259 patients in 1988, and 268 patients in 1989, including 190 patients who consecutively received both examinations. Blood PCB concentrations (mean +/- SE) were 4.78 +/- 0.22 ppb in 1988, and 4.47 +/- 0.17 ppb in 1989. The results of blood-chemical analysis were compared among four categorized concentrations of blood PCB, using the analysis of variance. Significant difference was observed for triglyceride (1988: p < 0.025, 1989: p < 0.005), but not for gamma-GTP, total-, and conjugated-bilirubin. In 1988, the mean triglyceride levels were 108, 137, 145, and 166 mg/dl at < 2.7, > or = 2.7, > or = 4.1, and > or = 6.1 ppb of blood of PCB, respectively. Corresponding figures in 1989 were 106, 129, 154, and 156 mg/dl at < 2.7, > or = 2.7, > or = 4.0, and > or = 5.7 ppb of blood PCB, respectively. Thus, clear positive association between blood PCB and serum triglyceride was observed in the patients twenty years after exposure.

Aged↗
PubMed1993

[A case of intra- and extracranially extensive metastatic brain tumor of tracheal cancer origin].

The authors report a case of metastatic brain tumor of tracheal cancer origin, itself a rare condition. A 55-year-old man was admitted with complaints of headache, atonic seizure of left lower limb and right temporal swelling. On admission, the patient had left recurrent nerve palsy. CT scan displayed right temporal bone destruction and ring-enhanced mass. MRI disclosed that the mass contained an inner necrotic region and a perifocal edema. Right common carotid angiogram revealed that the tumor was fed only by narrowed vessels of the middle meningeal artery. Subtotal removal of the tumor was performed, and histological examination revealed cranial metastasis of tracheal squamous cell carcinoma. Postoperative course was uneventful, and the patient underwent medical treatment for the primary lesion before post-operative brain-irradiation.

Brain Neoplasms↗
PubMed1992

Hepatitis B virus, cigarette smoking and alcohol consumption in the development of hepatocellular carcinoma: a case-control study in Fukuoka, Japan.

The roles of the hepatitis B virus (HBV), cigarette smoking and alcohol consumption in the etiology of hepatocellular carcinoma (HCC) were examined in a case-control study involving 204 patients with HCC and 410 control subjects in Fukuoka prefecture, where HCC risk is among the highest in Japan. Information on smoking and drinking habits was obtained by a detailed interview survey, and the results were analyzed in conjunction with serum hepatitis B surface antigen (HBsAg) status after adjustment for sex, age and other possible confounding factors. Individuals positive for serum HBsAg showed a relative risk (RR) for HCC of 13.8 (95% confidence interval, Cl 5.9 to 32.5), whereas heavy drinkers experienced about a 2-fold risk increase compared with non-drinkers. Light or moderate drinkers, however, demonstrated RRs near the unity. Some risk excess was observed among ex-smokers (RR = 1.5, 95% CI 0.8 to 2.8) and current smokers (RR = 1.5, 0.8 to 2.7) compared with non-smokers, but without evidence for a dose-response relationship in terms of pack-years. Analysis among HBsAg-negative subjects revealed similar non-significant association with smoking, and there was no clear interaction between alcohol and cigarette consumption on HCC risk. Other significant risk factors included positive histories of blood transfusion (RR = 3.7, 2.2 to 6.3) and familiar liver disease (RR = 2.6, 1.6 to 4.2). Attributable risk calculations suggest that chronic HBV infection and heavy drinking may account for 17% and 13% of HCC occurrence, respectively, in this high risk area. The association of cigarette smoking with HCC was not evident in our study.

Adult↗