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Biomedical subjects

K Tajima

Publications and source records attributed to K Tajima.

At least 235 records · Page 13Linked to original sources
PubMed1997

Mechanism and intermediate for formation of 2'-deoxyoxanosine.

A reaction mechanism for the direct formation of 2'-deoxyoxanosine (dOxo) from 2'-deoxyguanosine (dGuo) by nitrous acid (HNO2) or nitric oxide (NO) was explored by using guanosine (Guo) and its methyl derivatives. HNO2 treatment of 1-methylguanosine (1-Me-Guo) indicated that the exocyclic amino nitrogen (N5) of dOxo originates from imino nitrogen (N1) of dGuo. A short-lived intermediate detected in the Guo-HNO2 system by reversed phase (RP) HPLC was converted into oxanosine (Oxo) and xanthosine (Xao) at neutral pH. Based on these findings, we discuss the reaction mechanism for the formation of dOxo.

Deoxyguanosine↗
PubMed1997

[Risk factors of lung cancer--follow-up studies in Nagoya Japan].

A population-based follow-up study on the relationships between various environmental factors and risks of lung cancer has been conducted in Nagoya, Japan involving 24,489 inhabitants aged 40 or older. The baseline survey was conducted in 1985, using a self-recorded questionnaire. From a 10 year follow-up study, 161 cases with a newly diagnosed lung cancer (120 male cases and 41 female cases) were identified. Various environmental factors were related to the subsequent risk of lung cancer incidence. Causal relationship between smoking and lung cancer was noticed for current male smokers (RR = 5.72; 95% CI = 2.50-13.08) and for current female smokers (RR = 2.05%; 95% CI = 0.97-4.32). However, relative risks for other environmental factors were not statistically significant except increased risk for frequent coffee drinking in males (aRR = 2.02; 95% CI = 1.34-3.05) and decreased risk for frequent intake of green/yellow vegetables in females (aRR = 0.47; 95% CI = 0.23-0.94).

Adult↗
PubMed1996

Cloning, sequencing and complementation analysis of the recA gene from Prevotella ruminicola.

Degenerate PCR primers based on conserved RecA protein regions were used to amplify a portion of recA [corrected] from Prevotella ruminicola strain 23, which was used as a probe to isolate the full-length recA gene from the P. ruminicola genomic library. The P. ruminicola recA gene encoded a protein of 340 amino acids with a molecular mass of 36.81 kDa, P. ruminicola RecA was highly similar to other RecA proteins and most closely resembled that of Bacteroides fragilis (75% identity). It alleviated the methyl methanesulfonate and mitomycin C sensitivities of Escherichia coli recA mutants, but did not restore the resistance to UV-light irradiation. Mitomycin C treatment of otherwise isogenic E. coli strains showed a higher level of prophage induction in a recA harboring lysogen.

Amino Acid Sequence↗
PubMed1996

Protective factor against progression from atrophic gastritis to gastric cancer--data from a cohort study in Japan.

To investigate the association between atrophic gastritis and gastric cancer and to identify the risk and protective factors for the progression of atrophic gastritis to cancer, we conducted a prospective study on 5,373 subjects with neither cancer nor resected stomach who underwent gastroscopic examination and completed a life-style questionnaire. After an average of 6 years of follow-up, 69 gastric-cancer cases were identified, 65 from the subjects without atrophic gastritis and 4 from the subjects without atrophic gastritis. The presence of atrophic gastritis increased the risk of gastric cancer 2.19-fold, the risk trend increasing with the degree and the extension of atrophy [relative risk (RR) 1.60 for mild atrophy and 2.85 for moderate and severe atrophy]. Among the subjects with atrophic gastritis, family history of gastric cancer (RR 2.27) and a preference for spicy food (RR 1.84) increased the risk and self-administered meal controls, such as portion reduction (RR 0.44) reduction of salty food (RR 0.56) and the change to the consumption of easily digested food (RR 0.57) decreased the risk of gastric cancer. The results of this study suggest that atrophic gastritis increases the risk of gastric cancer but that dietary modification prevents the progression from atrophic gastritis to gastric cancer, regardless of pre-cancerous lesions.

Adult↗
PubMed1996

Deposits of eosinophil granule proteins in eosinophilic cholecystitis and eosinophilic colitis associated with hypereosinophilic syndrome.

A case of hypereosinophilic syndrome with eosinophilic colitis, eosinophilic cholecystitis, and increased serum levels of interleukin-5 (IL-5) and soluble interleukin-2 receptor (sIL-2R) is reported. Immunohistochemical studies of cholecystectomy and colon biopsy specimens with monoclonal antibodies, which are specific for activated eosinophils, secreted eosinophil cationic protein (ECP) and for major basic protein (MBP), demonstrated the presence of numerous activated eosinophils, secretion of ECP, and deposition of MBP in areas of tissue damage. These findings suggest that in eosinophilic cholecystitis and eosinophilic colitis, activated eosinophils infiltrate and degranulate in each tissue, releasing eosinophil granule proteins that produce tissue damage.

Adult↗
PubMed1996

Urinary excretion of tetrahydro-beta-carbolines relating to ingestion of alcoholic beverages.

Tetrahydro-beta-carbolines, formed from aldehydes and tryptamine, have been suggested as potential biochemical markers for alcoholism. The excretion of 1-methyl-1,2,3,4-tetrahydro-beta-carboline (MTBC) and 1,2,3,4-tetrahydro-beta-carboline (TBC) in human urine was studied to assess their possible origin. In urine collected after a drinking party, MTBC and TBC were excreted in significantly higher concentrations compared with sobriety. MTBC and TBC were contained in beer and wine at ng/ml levels, but not in distillate alcoholic beverages such as whisky, brandy, gin, etc. The urinary excretion of MTBC and TBC was elevated after drinking beer, whereas no change was observed after drinking whisky. When a human subject was orally administered with deuterated L-tryptophan together with drinking whisky, deuterated tryptamine was increasingly excreted in urine. However, no increase was found in urinary deuterated MTBC. These results indicate that the urinary excretion of MTBC and TBC associated with alcohol ingestion does not imply promotion of their in vivo formation, but the exogenous supply of MTBC and TBC by drinking alcoholic beverages containing them.

Adolescent↗
PubMed1996

Patients' expectations of information provided at cancer hospitals in Japan.

In order to survey patients' views on disease and treatment information that should be provided at hospitals, an anonymous self-administered questionnaire was distributed to patients at Aichi Cancer Center Hospital in 1995. All eligible first-visit outpatients (97 persons), randomly selected revisit outpatients (99 persons; about one in ten refused), and all except six eligible inpatients in good condition at discharge (97 persons) responded. Out of 293 patients (115 males, 174 females and 4 unspecified), 74% answered that they wanted to be informed of their diagnosis irrespective of circumstances, 20% answered that they would want to be informed only in certain circumstances, and 2% did not want to be informed at all. There were no significant differences in response among the three sources of patients. Inpatients wanted more (81%) to be explained about recommended therapy than either first-visit outpatients (67%) or revisit outpatients (67%). The majority considered that about a 30-minute explanation was needed using pamphlet-like written materials or video. When asked what information was needed when choosing a cancer hospital, 71% specified information on the specialty of the hospital, 57% the content of the care provided, 23% the name and specialty of the doctors, 20% the waiting period before scheduled admission, 13% the average admission period, 11% the number of patients with the same disease, 10% the waiting time at the outpatient clinic, 6% the meal menu, and 4% the number of private wards. Forty-three percent wanted an information service covering all hospitals in the region through an information center. The results revealed that patients at this cancer hospital required information on their disease, treatment, and hospital specialty.

Adult↗
PubMed1996

Prognostic factors and a predictive model of follicular lymphoma: a 25-year study at a single institution in Japan.

The incidence of follicular lymphoma in Japan is far lower than that in western countries, and no large-scale clinicopathologic studies on this neoplasm have been conducted in Japan. We reviewed histopathological specimens from 118 of 135 patients who had been diagnosed as having follicular lymphoma between 1968 and 1993. Prognostic factors influencing survival were analyzed using univariate and multivariate analyses. Factors that were independently significant upon multivariate analysis were incorporated into a predictive model. Ninety-three patients (78.8%) had a confirmed diagnosis of follicular lymphoma. Twenty-one of the remaining 25 patients were categorized as having other lymphoma subtypes, and four patients showed indefinite findings or those suggesting diseases other than lymphoma. Major characteristics of the 93 patients with follicular lymphoma were a median age of 53 years (20-85); 59 males (63%) and 34 females (37%); small cleaved cell type in 33 (35%), mixed cell type in 41 (44%) and large cell type in 19 (20%); stage I/II in 41 (44%) and stage III/IV in 50 (54%). Overall survival was 71% at 5 years, 58% at 10 years, and 43% at 15 years with a median survival of 13.3 years. Multivariate analysis revealed that two variables, age (>60) (P=0.001) and the serum LDH level (>1 x normal value) (P=0.026), were unfavorably significant prognostic factors influencing survival. The predictive model using these two variables identified three risk groups with estimated five-year survival rates of 88.5%, 56.8%, and 31.5%. Age and serum LDH were significant predictors of survival in Japanese patients with follicular lymphoma. Our predictive model may provide a basis for future therapeutic trials against follicular lymphoma in Japan.

Adult↗
PubMed1996

Tobacco, alcohol and dietary factors associated with the risk of oral cancer among Japanese.

The mortality rate among Japanese men due to oral cancer is increasing, but risk factors among Japanese other than smoking and drinking have not been examined. To investigate the dietary factors involved in oral cancer, we conducted a hospital-based case-referent study in Aichi, Japan. Cases comprised 189 men and 77 women aged 20-79 years with one of the following cancers: tongue, mouth, oropharynx and hypopharynx. The reference group comprised 9,858 male and 26,669 female out-patients without cancer. Smoking and drinking were highly associated with an increased risk of oral cancer. Japanese sake showed a lower odds ratio (OR) than beer or hard liquor (OR= 3.6, 4.5 and 4.8, respectively). In the cross analysis between smoking and drinking, smoking combined with drinking increased the risk of oral cancer to three times that of smoking only (OR=6.2 vs. 2.2). Frequent intake of raw vegetables (OR = 0.5) and fruit (OR = 0.5) were inversely associated with the risk of oral cancer after adjustment for age, sex, smoking, drinking and year of visit. Western-style breakfast and salty food preference decreased the risk of oral cancer, and salty food preference was still statistically significant by multivariate analysis (OR= 0.7). In conclusion, smoking cessation, drinking control and frequent intake of raw vegetables and fruit among Japanese are likely to be effective preventive measures against oral cancer.

Adult↗
PubMed1996

Subsite (cervix/endometrium)-specific risk and protective factors in uterus cancer.

In Japan the incidence of cervical cancer has been high, but has recently been decreasing gradually, while the incidence of endometrial cancer is running at lower levels but is gradually increasing. To clarify the common and/or specific risk and/or protective factors of cervical cancer(CC) in contrast with endometrial cancer (EC), a comparative case-control study was conducted at the Aichi Cancer Center Hospital, Japan. In total, 556 CC cases and 145 EC cases were included and 26,751 women, confirmed as free of cancer, were chosen as the common control group. Odds ratio and its 95% confidence interval (95%CI) for each exposure variable were estimated by using an unconditional logistic regression model adjusted for age and first-visit year. Habitual smoking and experience of pregnancy increased the risk of CC, while decreasing the risk of EC. Greater body mass index (>20), daily intake of fruit and more frequent intake of boiled or broiled fish (>1-2 times/week) decreased the risk of CC, whereas they increased the risk of EC. Daily intake of milk decreased the risk of CC. The results obtained from this study suggest that several EC-increasing risk factors are in fact CC-decreasing determinants. The observed risk reduction in both CC and EC by physical exercise and dietary control for health is noteworthy from the public health standpoint and warrants further investigation.

Adult↗
PubMed1996

High prevalence of arthropathy in HTLV-I carriers on a Japanese island.

OBJECTIVE: To determine the aetiological relationship between human T cell leukaemia virus type-I (HTLV-I) and arthritis, by performing an epidemiological study of the inhabitants of Tsushima, an island northwest of the main island of Kyushu, Japan, which is an endemic area of HTLV-I. METHODS: A total of 7087 people underwent an annual health check, and those with arthropathy had further physical and radiological examinations by rheumatologists. The presence of HTLV-I antibody was determined by the particle agglutinin method, and integration of the proviral DNA in peripheral lymphocytes was confirmed by polymerase chain reaction. RESULTS: HTLV-I was positive in 26.1% of inhabitants; the incidence increased to 37.0% in patients with symptoms of polyarthritis. The prevalence of rheumatoid arthritis (RA) was significantly different between HTLV-I carriers (0.56%) and non-carriers (0.31%). The stage of bone destruction in HTLV-I carriers with articular symptoms was milder than that in RA patients without HTLV-I. The relative risk of HTLV-I infection for polyarthritis was 1.66 (p < 0.05). CONCLUSION: This is the first epidemiological report clarifying the association between HTLV-I and polyarthritis. Our results suggest that this viral infection has a relationship to RA.

Antibodies, Viral↗
PubMed1996

Risk factors of thyroid cancer among women in Tokai, Japan.

To analyze the risk factors of thyroid cancer among Japanese women who generally consume much more iodine than Europeans, we conducted a hospital-based case-referent study at Aichi Cancer Center Hospital (ACCH) in Nagoya, Japan. Ninety-four female patients aged between 20-79 years with papillary or follicular carcinoma of the thyroid, and 22,666 female outpatients without cancer were used. Past history of benign thyroid mass or goiter (odds ratio: OR = 13.9) and hyperthyroidism (OR = 5.0) showed increased ORs of thyroid cancer. Thyroid cancer cases consumed coffee less frequently (OR = 0.5) and had had more experience of delivery than referents (> or = 3 times; OR = 2.5). Western style breakfast (OR = 0.5) also decreased the OR. For the multivariate analysis, past history of thyroid diseases (OR = 4.3) was positively associated with the risk of thyroid cancer and everyday coffee consumption (OR = 0.6) tended to decrease the risk. These results suggest that thyroid hormone-related factors may be involved in the risk of thyroid cancer in Japan, too. To clarify the risk involved in Japanese food, another comparative study including detailed information on iodine intake between countries and individuals is required.

Adenocarcinoma, Follicular↗
PubMed1996

Epidemiology of AIDS/HIV in Japan.

The data obtained from the national reporting system of acquired immune deficiency syndrome (AIDS) and its causative immune deficiency virus (HIV), the epidemic pattern of AIDS cases and HIV carriers in Japan from 1985 to 1995 could be summarized as follows: 1) the total number of reported AIDS cases and HIV carriers were 1,154 and 3,524 which included 167 and 915 foreigners, respectively; 2) among them the number of HIV carriers in hemophiliacs transmitted through HIV contaminated blood products was 1,806, including 582 AIDS victims; 3) excluding these hemophiliacs, there are 572 AIDS cases (167 foreigners) which shared risk factors for heterosexual contacts (37%) and homosexual contacts (31%), respectively; 4) on the other hand, more than 50% were heterosexuals and only 20% were homosexuals in 1,718 HIV carriers (915 foreigners); 5) the peak incidence is 33% in the 30s in AIDS, while more than 50% are in their 20s; 6) male-to-female ratio was 6.8 in AIDS cases but only 1.1 in HIV carriers; 7) the estimated number of HIV carriers in 2000 was 6,300-8,500 in Japanese and 700-1,700 in foreigners, respectively. From the above mentioned epidemic pattern of AIDS/HIV in Japan, we have to recognize that the recent number of HIV infection is actually increasing and the most of current HIV carriers even in foreigners are infected with HIV in our country and general activities for AIDS prevention in Japan and neighboring Asian countries should be promoted.

Acquired Immunodeficiency Syndrome↗
PubMed1996

[Questionnaire survey of AIDS examination recipients at government-run public health center regarding AIDS awareness promotion and HIV examinations].

An anonymous questionnaire survey was conducted among persons who had undergone screening for AIDS at public health centers under the auspices of 7 local government bodies (Hokkaido, Metropolitan Tokyo, Aichi Prefecture, Osaka Prefecture, Kobe City, Saga Prefecture, Okinawa Prefecture). There were 1,230 replies, for a response rate of 46.8%. Questions in the survey pertained to general knowledge of AIDS, information desired by the recipients, desired ways to foster awareness, and a desirable examination system. A comparison was made in terms of gender, marriage status (married, single) and age (less than 40 years of age, more than 40 years of age), respectively. The survey results were as follows. 1. Concerning the infection route, accurate response rate was low with regard to the mother-child infection, mosquito transmission, and use of contaminated needles. 2. Desired methods to promote AIDS awareness expressed among replies were given in the following order or frequency: "information via radio and TV," "spread of knowledge through telephone consultation," and "holding an AIDS Week or similar kinds of campaigns." 3. Information sought by respondents frequently included AIDS treatment, pathology, and spread. This trend was most obvious among those under 40 years of age. 4. As for the AIDS examination system, replies most often reflected the hope that the examination site would be the Public Health Center, the charge would be gratis, and that one could be examined at night during the week, and on days off. 5. For those undergoing examination where there was no actual concern of possibility of HIV infection, single persons, accounted for around 80% of the overall. 6. More than half of those who had been examined mentioned having experienced concerns about maintaining confidentiality at the time they were examined.

Acquired Immunodeficiency Syndrome↗
PubMed1996

Japanese risk behaviors and their HIV/AIDS-preventive behaviors.

This study is to identify the risk behaviors of the Japanese that may lead to HIV infection and the behaviors that prevent such infection, as well as their background factors. Two behavioral surveys were conducted for the present study. (1) For international comparison on knowledge, attitudes, beliefs, and practices (KABP) related to HIV/AIDS, we conducted a survey on a sample of 10,000 adults, randomly selected from a nationwide population in Japan; and (2) for sexual partner relation, we conducted a survey on a sample of 10,000 adults randomly selected from a population in five major cities of Japan. Our main findings include: (1) Most of the Japanese adult did not regard AIDS as a major threat in the area where they lived; (2) People in their twenties are too casual about "having sex without using a condom with someone they've met for the first time and know little about"; (3) Thirteen percent (19% male, 8% female) of those with a steady sex partner including a spouse, on average, had sex with 2.4 non-steady partners in the previous year; and (4) Only 25 percent used condoms always when they engaged in casual sex during the previous four weeks. These risk behaviors of the Japanese adults might lead to an explosive rise in the number of HIV-infected in the near future unless steps are taken immediately to prevent it.

Adult↗
PubMed1996

[Survival factors in healthy aging among rural Japanese residents of Aichi].

To investigate survival factors in healthy aging among rural Japanese elderly residents, a nested case-control study was conducted. Subjects who answered questionnaires in 1985 were followed for 10 years. Cases comprised 124 men and 109 women who, in 1995, were 75 years old or over, and whose activities of daily living were active enough to cope for themselves. Controls were selected from subjects who died between 1987 and 1994. One control per case was randomly selected, and matched to each case for sex and birth-year (+/- 2 years). The survival odds ratio (sOR) was calculated by using a conditional multiple logistic regression model. An sOR greater than 1.0 was observed for frequent intake of eggs, regular daily routine, adaptability to changes, leisure time exercise and a health examination at least once within 3 years. In both men and women present or past history of heart disease, cerebrovascular disease and diabetes, family history of hypertension, and in women, smoking were negatively associated with survival. By multivariate analysis, adaptability to change in men, and regular daily routine and health examinations in women were positively associated to survival. Smoking and history of chronic disease were negatively associated with survival, in both men and women. In conclusion, it is suggested that psychological factors and recent health examinations were positively associated to survival in healthy aging, and habitual smoking and chronic disease contributed negatively to survival. These results require further careful evaluation to determine whether the factors are associated with cause or effect.

Aged↗
PubMed1995

Formation of tetrahydro-beta-carbolines in human saliva.

When human saliva obtained after cigarette smoking was incubated in the presence of tryptamine, the formation of 1,2,3,4-tetrahydro-beta-carboline (TBC) and 1-methyl-1,2,3,4-tetrahydro-beta-carboline (MTBC) was observed in a short time. After incubation with tryptamine (2.5 micrograms/microliter) for 10 min, the concentrations of TBC and MTBC formed were 3.27 +/- 0.94 and 0.35 +/- 0.17 ng/microliter, respectively. The formation of TBC and MTBC in intact saliva and in saliva heated at 100 degrees for 10 min was compared, but no significant difference was found. The analysis of foodstuffs showed that significant amounts of tryptamine were contained in various foods and beverages. The analysis of cigarette smoke solutions and immersion solutions of denture-base acrylic resins showed that ng-micrograms/microliter levels of formaldehyde and acetaldehyde were contained in cigarette smoke and leached from dental resins. These results indicate that both precursors, tryptamine and aldehydes, coexist in oral environments and that their interaction to form TBC and MTBC potentially occurs in human saliva without participation of salivary enzyme.

Adult↗