Objective: To investigate the relationship between green tea consumption and subsequent risk of gastric cancer at different anatomical subsites in a population-based prospective study. Methods: The ...Japan Public Health Center-based prospective study (JPHC Study) was established in 1990 for Cohort I and in 1993 for Cohort II. Among 72,943 subjects (34,832 men and 38,111 women), 892 gastric cancer cases (665 men and 227 women) were identified from 1990 to 2001. Results: While no association between green tea consumption and gastric cancer was observed among men, a decreased risk of gastric cancer was observed among women after adjustment for potential confounding factors. This result was more remarkable when only the tumors in the distal portion were analyzed; for that subsite, the relative risk was 0.51 (95% confidence interval 0.30-0.86) in the highest category of green tea consumption (5 or more cups per day versus less than 1 cup per day) (p for trend = 0.01). The null association for upper-third gastric cancer was consistent for both sexes. Conclusions: An inverse association between green tea consumption and distal gastric cancer was observed among women. More prospective studies with detailed information are needed to confirm the role of green tea in the occurrence of gastric cancer.
The odds ratio was 1.462 with 95 % confidence interval ranged from 0.998 to 2.144. (2013) Correction: Smoking Cessation Increases Short-Term Risk of Type 2 Diabetes Irrespective of Weight Gain: The ...Japan Public Health Center-Based Prospective Study.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
A base excision repair enzyme, NTH1, has activity that is capable of removing oxidized pyrimidines, such as thymine glycol (Tg), from DNA. To clarify whether the NTH1 gene is involved in gastric ...carcinogenesis, we first examined the NTH1 expression level in eight gastric cancer cell lines, and the results showed that NTH1 expression was downregulated in all of them, including cell line AGS. Next, a comparison of excisional repair activity against Tg by empty vector-transfected AGS clones and FLAG-NTH1-expressing AGS clones showed that a low NTH1 expression level led to low capacity to repair the damaged base in the gastric epithelial cells. Reduced messenger RNA expression of NTH1 was also detected in 36% (18/50) of primary gastric cancers. Moreover, immunohistochemical analysis revealed that NTH1 was predominantly localized in the cytoplasm in 24% (12/50) of the primary gastric cancers in contrast to the nuclear localization in non-cancerous tissue, suggesting impaired excisional repair ability for nuclear DNA. No associations between clinicopathological factors and NTH1 expression level or localization pattern were detected in the gastric cancers. Next, we found two novel genetic polymorphisms, i.e. c.-163C>G and c.-241_-221del, in the NTH1 promoter region, and a luciferase assay showed that both were associated with reduced promoter activity. However, there were no associations between the polymorphisms and risk of gastric cancer in a gastric cancer case–control study. These findings suggested that downregulation of NTH1 expression and abnormal localization of NTH1 may be involved in the pathogenesis of a subset of gastric cancers.
Few data have been available on the sex-specific magnitude of the smoking effect on the risk of coronary heart disease (CHD) in Asia.
A population-based prospective cohort study of 19 782 men and 21 ...500 women aged 40-59 years between 1990-1992 and 2001 was conducted to examine the relationship between smoking status and the risk of CHD.
A total of 260 incidences of CHD were confirmed among men, including 174 myocardial infarctions (MI). The numbers among women were 66 and 43, respectively. The multivariate relative risk 95% confidence interval (CI) for current smokers versus never-smokers in men after adjustment for cardiovascular risk factors, several life style factors and public health centre was 2.85 (1.98, 4.12) for total CHD and 3.64 (2.27, 5.83) for MI. These respective risks in women were 3.07 (1.48, 6.40) and 2.90 (1.18, 7.18). Among men, a dose-dependent relationship was observed between the number of cigarettes and the risk of MI. The population-attributable risk per cent (95% CI) of CHD was 46% (34, 55) in men and 9% (0, 18) in women. Smoking cessation, however, led to a rapid decline in the CHD risk within 2 years.
Smoking raises the risk of CHD significantly in both sexes of middle-aged Japanese, with large public health significance especially in men. Smoking cessation would have an immediate effect on risk reduction.
Although dietary risk factors may differ between localized and advanced prostate cancer, data on associations between the consumption of fruits and vegetables and risk of localized and advanced ...cancers are limited. We examined associations between fruit and vegetable consumption and risk of prostate cancer in a Japanese population. During 1995-1998, a validated food frequency questionnaire was administered to 43,475 men aged 45-74 yr. During 321,061 person-years of follow-up until the end of 2004, 339 cases of prostate cancer were identified. Consumption of fruits or total vegetables was not associated with a decreased risk of total prostate cancer, with corresponding multivariate hazard ratios of the highest vs. lowest quartiles of 1.09 (95% CI = 0.77-1.53; trend P = 0.39) for fruits and 1.33 (95% CI = 0.93-1.91; trend P = 0.52) for total vegetables. Also, no association was observed for intake of either fruits or vegetables (total or any subtype) with localized or advanced prostate cancer. This prospective cohort study suggests that consumption of fruits or vegetables may not be associated with the risk of either localized or advanced prostate cancer in Japanese men. However, the possibility of confounding by detection bias on the risk of localized cancer could not be totally ruled out.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, OILJ, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK, VSZLJ
We conducted a population‐based, double‐blind, randomized controlled trial to examine the effect of vitamin C supplementation on serum pepsinogen (PG) level, Helicobacter pylori (H. pylori) ...infection, and cytotoxin‐associated gene A (Cag A) status. Subjects aged 40 to 69 years living in one village in Akita prefecture, a high‐risk area for gastric cancer in Japan, were recruited through annual health check‐up programs. Among 635 subjects diagnosed as having chronic gastritis on the basis of serum PG levels, after excluding ineligible cases, 439 subjects were assigned to one of four groups using a 2×2 factorial design (0 or 15 mg/day β‐carotene and 50 or 500 mg/day vitamin C). However, based on the results from two β‐carotene trials in the United States, we discontinued β‐carotene (vitamin C supplementation was continued). Finally, 120 subjects in the low‐dose group (vitamin C 50 mg), and 124 subjects in the high‐dose group (vitamin C 500 mg) completed the 5‐year supplementation. The difference in the change of PGI/II ratio between baseline and after 5‐year follow up was statistically significant between the intervention groups among those who completed the supplementation: ‐0.25 for the low‐dose group and ‐0.13 for the high‐dose group (P=0.046). To conclude, vitamin C supplementation may protect against progression of gastric mucosal atrophy. (Cancer Sci 2003; 94: 378–382)
Previous studies of Japanese migrants have suggested that the increase in colorectal cancer rates occurring after migration is slower among Japanese Brazilians than among Japanese Americans. We ...hypothesized that this difference may partly reflect differences in vegetable and fruit intake between the populations. Using data from validation studies of food frequency questionnaires being used in comparative case–control studies of colorectal adenoma in Tokyo, São Paulo, and Hawaii, plasma carotenoid, retinol, tocopherol, and coenzyme Q10 levels were measured by high-performance liquid chromatography, and 25-hydroxy vitamin D levels were estimated by enzyme-linked immunosorbent assay. Plasma levels were compared by analysis of covariance between 142 Japanese in Tokyo, 79 Japanese Brazilians in São Paulo, and 78 Japanese Americans in Hawaii. Overall, we found significantly lower plasma carotenoid levels, except for lycopene levels, and retinol levels in Japanese Americans compared with Japanese in Tokyo and Japanese Brazilians. The plasma total carotenoid level was highest in Japanese Brazilians. Compared with the mean level among Japanese Brazilians (1741.2 ng/ml), P for difference was 0.03 among Japanese in Tokyo (1514.4 ng/ml) and less than 0.01 for Japanese Americans (1257.7 ng/ml). Plasma lycopene and tocopherol levels did not substantially differ between the three populations. We also found significantly lower plasma levels of 25-hydroxy vitamin D and total coenzyme Q10 in Japanese in Tokyo than in Japanese Americans and Japanese Brazilians. Higher levels of plasma carotenoids among Japanese Brazilians than among Japanese in Tokyo and Hawaii may have contributed to the slower pace of the increase in colorectal cancer rates observed in that population after migration.
To explore whether polymorphisms in
AhR,
ARNT, and
AhRR contribute to endometriosis susceptibility and severity.
Case control study.
Hospital.
One hundred thirty-eight Japanese women with or without ...endometriosis, diagnosed endoscopically.
Endoscopic laparoscopy, with blood samples for genotyping obtained before the laparoscopic examination for genomic DNA extraction from peripheral leukocytes.
AhR,
ARNT, and
AhRR polymorphisms were genotyped using real-time polymerase chain reaction (PCR) analysis. Odds ratios and 95% confidence intervals were calculated for
AhR,
ARNT, and
AhRR genotypes to evaluate the risk of endometriosis. Associations between these polymorphisms and stage of endometriosis were also examined.
The C/G + G/G genotypes at codon 185 of
AhRR showed a statistically significant association with risk of endometriosis (adjusted odds ratio, 2.53; 95% confidence interval, 1.16–5.55). Furthermore, a statistically significant trend associated the C/G + G/G genotypes with the clinical stage of endometriosis. No statistically significant association was observed between
AhR codon 554 or
ARNT codon 189 polymorphisms and endometriosis.
AhRR codon 185 polymorphism was associated with susceptibility to and severity of endometriosis in Japanese women.
Abstract Heterocyclic aromatic amines (HAAs), which are formed from the reaction of creatine or creatinine, amino acids, and sugars in meat and fish cooked at high temperatures, have been shown to be ...mutagenic in bacterial assays and carcinogenic in animal models. Following advances in the dietary assessment of HAA intake in epidemiological studies - including development of a validated meat-cooking module and a specialized food composition database - a number of epidemiological studies have specifically examined the association of HAA intake and cancer risk, most of which were conducted in Western countries. Given that dietary habits and cooking methods differ across countries, however, epidemiological investigation of dietary HAA intake requires a population-specific assessment method. Here, we developed a practical method for assessing dietary HAA intake among Japanese using a food frequency questionnaire (FFQ) and evaluated its validity for use in epidemiological studies by comparison with 2-amino-1-methyl-6-phenylimidazo 4,5-b pyridine (PhIP) levels in human hair. The Japan Public Health Center-based Prospective Study reported that daily intake of HAAs among Japanese was relatively low, and that more than 50% of total intake in mainland Japan was derived from fish. Only four case-control studies in Japan have been reported so far, for colorectal, stomach and prostate cancer, and colorectal adenoma. A statistically significant positive association was found between 2-amino-3,4-dimethylimidazo 4,5-f quinoline (MeIQ) and the risk of colorectal adenoma and between individual and total HAAs and the risk of prostate cancer. In contrast, no association was observed for colorectal or stomach cancer, or for colorectal adenoma among men. We also found that the limited and inconsistent findings among epidemiological studies are due to the difficulty in assessing exposure levels of HAAs. In addition to further evidence from prospective cohort studies in Japanese based on dietary HAA intake estimated by FFQs, studies using other methods to assess HAA exposure, such as biomarkers, are highly anticipated.
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