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Biomedical subjects

K Tajima

Publications and source records attributed to K Tajima.

At least 253 records · Page 14Linked to original sources

Subsite-specific risk factors for colorectal cancer: a hospital-based case-control study in Japan.

To investigate the subsite-specific risk factors for colorectal cancer, we conducted a case-control study, using a common questionnaire which inquired about general lifestyles over the past five years (1988-92), at the Aichi Cancer Center Hospital, Nagoya, Japan. This study compared 432 patients with histopathologically diagnosed colorectal cancer (94 proximal colon [cecum, ascending colon, transverse colon]; 137 distal colon [descending colon, sigmoid colon]; 201 rectum [rectosigmoid, rectum]); and 31,782 first-visit outpatient controls who were free from cancer. In both genders, habitual smoking selectively increased the risk for rectum cancer. Soft or loose feces increased the risk for all subsites of colorectal cancer, particularly in female rectum cancer (odds ratio [OR] = 4.5). Among female dietary habits, Japanese-style foods decreased the risk for distal colon cancer, but increased the risk for proximal colon cancer. These results suggested that the risk factors for colorectal cancer differ by subsite among such a low-risk population as the Japanese. It is suggested also that 'irritable bowel' (soft or loose feces) might be associated with distal subsites of colorectal cancer, independently or combined with habitual smoking.

Adult↗

Incidence of human T lymphotropic virus type I seroconversion after age 40 among Japanese residents in an area where the virus is endemic.

To clarify how seroconversion after age 40 years contributes to the seroprevalence of human T lymphotropic virus type I (HTLV-I), Japanese residents were studied in an area of Kyushu in which HTLV-I is endemic. Cross-sectional data showed higher seroprevalences among subjects > or = 40 than in those < 40 years old (27.0% vs. 7.9%). The prevalence was also greater in women than men (25.5% vs. 17.6%). Six hundred subjects > or = 40 years old were tested during 1976-1993. Among 8 who seroconverted, 5 had an HTLV-seropositive spouse and 2 seroconverted after blood transfusions. The incidences per 1000 person-years of seroconversion in age groups 40-49, 50-59, and > or = 60 years were, respectively, 0.0, 0.0, and 3.3 (range, 1.38-5.13) in men and 0.0, 5.3 (range, 0.11-7.99), and 1.4 (range, 0.00-1.60) in women. The seroconversion incidence was insufficient to account for the rise of seroprevalence in those > or = 40 years old, especially among women. These results suggest that the high rate and sex discordance in HTLV-I seroprevalence after age 40 may depend mainly on the birth cohort effect for vertical or horizontal transmission.

Adult↗

Prolongation of epidural anesthesia in the rabbit with the use of a biodegradable copolymer paste containing lidocaine.

Prolongation of the drug effect using a drug-delivery system has recently been introduced in local anesthesia. In this study, we investigated the prolonging effect of an epidurally injected biodegradable copolymer paste containing 10% lidocaine (Lid-CoPol). Twenty-nine rabbits were studied. A catheter was placed in the epidural space at the level of L6-7 in each animal. A solution of 10% lidocaine (Group I, n = 12), or a copolymer containing 10% lidocaine (Lid-CoPol), (Group II, n = 12) or copolymer paste only (Group III, n = 5) was injected epidurally at a dose of 0.15 mL/kg. The effect of each drug was assessed by evaluation of response to pain stimulation and of the degree of motor block produced. The plasma lidocaine concentration was also measured consecutively in five animals of both Groups I and II. The duration of sensory and motor block of Lid-CoPol was 800% and 975% longer, respectively, than that of plain lidocaine solution. Plasma lidocaine concentration reached a maximum 5 min after injection (5.5 +/- 0.5 micrograms/mL) in Group I. In Group II, the level reached a maximum 30 min after injection (3.7 +/- 1.5 micrograms/mL). The findings are attributed in part to the slow release of lidocaine from the biodegradable copolymer paste, which is suggested as a new drug-delivery system for local anesthetics.

Anesthesia, Epidural↗

A large-scale, hospital-based case-control study of risk factors of breast cancer according to menopausal status.

We conducted a large-scale, hospital-based case-control study to evaluate differences and similarities in the risk factors of female breast cancer according to menopausal status. This study is based on a questionnaire survey on life style routinely obtained from outpatients who first visited the Aichi Cancer Center Hospital between January 1, 1988 and December 31, 1992. Among 36,944 outpatients, 1,186 women with breast cancer detected by histological examination were taken as the case group (607 premenopausal women and 445 postmenopausal women) and 23,163 women confirmed to be free of cancer were selected as the control group. New findings and reconfirmed factors of breast cancer were as follows. 1) The risk of at least one breast cancer history among subjects' first-degree relatives was relatively high among pre- as well as post-menopausal women. 2) A protective effect of physical activity against breast cancer was observed among both pre- and post-menopausal women. 3) Dietary control decreased the risk of premenopausal breast cancer. 4) Current smoking and drinking elevated the risk of breast cancer in premenopausal women. 5) Decreasing trends of breast cancer risk were associated with intake of bean curd, green-yellow vegetables, potato or sweet potato, chicken and ham or sausage in premenopausal women, while in postmenopausal women a risk reduction was associated with a more frequent intake of boiled, broiled and/or raw fish (sashimi). Further study will be needed to clarify the age group- and/or birth cohort-specific risk factors for breast cancer among the young generation in Japan.

Adult↗

Epidemiological features of HTLV-I and adult T cell leukemia.

Adult T-cell leukemia (ATL) patients and human T-cell leukemia virus type I (HTLV-I) carriers are clustered in limited groups in the world, especially among Japanese in Asia, Blacks in Central Africa, Melanesians in Papua New Guinea and Andeans in South America. The major transmission routes of HTLV-I under natural conditions are from mother-to-child through breast milk and from man-to-woman through semen. The whole life risk of ATL among persistent HTLV-I carriers is estimated at 2-6%. The detailed manifestation mechanism of ATL is not yet clarified; however, it is certain that HTLV-I infection in infancy is the main cause of ATL. Therefore, the prevention measure against mother-to-child transmission of HTLV-I is indispensable from a viewpoint of public health.

Adult↗

Gastrointestinal and skin lesions in piglets naturally infected with pseudorabies virus.

Pseudorabies virus (PRV) infection was diagnosed in 4 piglets from a litter by immunohistopathologic examination and virus isolation. Three piglets had moderate to severe neuronal degeneration, and PRV antigen was detected in Auerbach's myenteric plexus and Meissner's submucosal plexus of the gastrointestinal tract. One piglet had 2 types of skin lesions. One lesion appeared on the hip and ear and was characterized by ballooning degeneration, necrosis of epithelial cells, and intranuclear inclusion bodies. The other was found on the ear and hematoma-like lesion was composed of fibrinoid exudation and degenerative connective tissue. PRV antigen was clearly demonstrated in both skin lesions. These results suggested that degeneration of myenteric plexuses might be another characteristic of lesions in PRV-infected pigs and that the virus spreads by interaction between the skin and myenteric plexuses to the central nervous system.

Animals↗

Suppressive effect of molybdenum on hepatotoxicity of N-nitrosodiethylamine in rats.

In order to elucidate the mechanism by which molybdenum prevents the carcinogenesis of N-nitroso compounds, the effects of Na2MoO4-pretreatment on N-nitrosodiethylamine (NDEA)-induced DNA strand breaks, fluctuation in cation contents and lipid peroxidation levels in rat liver were examined. Male Wistar rats weighing 170-190 g were pretreated with Na2MoO4 (1.24 mmol/kg body weight, i.p., once a day) for 3 d and on day 4, they were exposed to NDEA (50 mg/kg body weight, once, i.p.). Three days after exposure to NDEA, the nitroso compound caused DNA strand breaks and disrupted potassium (K) and calcium (Ca) metabolism in the liver but did not affect lipid peroxidation levels. Na2MoO4-pretreatment prevented both NDEA-induced DNA damage and disruption of the metabolism of those cations but rather enhanced lipid peroxidation. These results suggest that Mo prevented NDEA-induced DNA damage by preventing disruption of intracellular Ca metabolism while stimulating the metabolism of the nitroso compound via a nontoxic pathway.

Animals↗

Noninvasive measurement of cerebral blood flow and glucose metabolic rate in the rat with high-resolution animal positron emission tomography (PET): a novel in vivo approach for assessing drug action in the brains of small animals.

The cerebral metabolic rate of glucose (CMRglc) and cerebral blood flow (CBF) in rats were estimated noninvasively with a high-resolution animal positron emission tomography (PET) system that we recently developed. Qualifications of CMRglc and CBF were attempted with radiotracers, 18F-2-fluoro-2-deoxyglucose and 15O-water, respectively. From the data obtained with PET, the CMRglc and CBF values under pretreatment conditions were respectively calculated as 51 +/- 14 mumol/min/100 g and 61 +/- 7 ml/min/100 g under pentobarbital-anesthesia. These values were in close agreement with published data obtained with the autoradiographic technique. Moreover, an increase of 69% (mean) in CBF was detected after i.v. acetazolamide administration. The results indicate that this high-resolution animal PET scanner holds great potential for the assessment of drug-related metabolic and circulatory effects in intact and experimental animals.

Acetazolamide↗

An autopsied case of T-cell rich B-cell lymphoma with general involvement.

Autoptic findings of a 77-year-old man with T-cell-rich B-cell lymphoma (TCRBCL) showed predominant infiltration of reactive T-cells with a minority population of neoplastic B-cells in liver, spleen, pancreas, adrenal gland, stomach, small intestine and heart, as well as, lymph node. DNA studies demonstrated dual rearrangement in the T-cell receptor beta (TCR beta), immunoglobulin heavy chain J region (IgJH) and kappa light chain J region (IgJ kappa) genes.

Aged↗

Desmoplastic fibroma. Aggressive curettage as a surgical alternative for treatment.

In this article, the authors present 5 patients with desmoplastic fibroma and review the literature. Four patients had aggressive curettage with bone graft, and 1 had aggressive curettage alone. Although the literature reports that many patients have recurrence after curettage, there have been no recurrences in these 5 patients during followup periods ranging from 5 years 6 months to 9 years. Although wide excision has been recommended in the literature, treatment with aggressive curettage achieved clinical and radiographic control of the lesions for at least an intermediate duration of followup.

Adolescent↗

[One-stage repair of interrupted aortic arch with ventricular septal defect].

Three neonates with type A interrupted aortic arch were successfully repaired through a median sternotomy incision during profound hypothermia and circulatory arrest in the past one year. Two aortic cannulas, a small plastic one (Cardicorp) in the ascending aorta and a long one inserted through the pulmonary artery and patent ductus arteriosus into the descending aorta. Two Pacifico's venous cannulas were inserted into superior and inferior vena cavae respectively. No dissection and encircling were required around three major branches from the aortic arch and both right and left pulmonary arteries. During a cooling phase a large ventricular septal defect was closed followed by circulatory arrest. It was possible to resect a patent ductus arteriosus and mobilize the descending thoracic aorta for anastomosis to the side of the ascending aorta without removal of the aortic cannula in the aorta. New instruments and development of cardiopulmonary bypass could bring a successful one-stage repair of interrupted aortic arch with ventricular septal defect more safely and easily than before.

Aorta, Thoracic↗

[AIDS/HIV related knowledge, attitude and behavior of acupuncture therapists in Aichi Prefecture].

To promote AIDS prevention measures in Japan, the actual state of knowledge, attitudes and behaviors (KAB) of workers at risk for HIV infection requires clarification. In the present study, acupuncture therapists in Aichi Prefecture were evaluated for level of their KAB. By using a self-administered questionnaire, the KAB condition of 500 acupuncture therapists was surveyed from September-November in 1993. Responses from 494 (98.8%) were available for analysis. Results showed that knowledge level on general issues regarding HIV epidemics was good. The main sources for information on AIDS/HIV were TV, general lectures, public reports and magazines. More than 80% of acupuncture therapists sterilize their needles by autoclave or boiling and 60% of them use disposable needles. Furthermore, 97% of the therapists reported utilizing one or the other of these methods. More than a half of them have participated in AIDS education programs. While about 30% of them responded that they are able to accept HIV carriers as clients, 20% of them expressed negative responses. There appears to be a discrepancy between their level of knowledge of HIV transmission routes and their practical attitude towards clients with AIDS and/or HIV carriers. A more appropriate education program based on behavioral science is desirable to lessen discrepancy distance between general knowledge and preferable behavior regarding AIDS/HIV.

Acquired Immunodeficiency Syndrome↗

Life-style and subsite of gastric cancer--joint effect of smoking and drinking habits.

To clarify the effects of life-style on gastric cancer by subsite focusing on the proximal part (cardia and fundus) and the distal part (pyloric antrum), a case-control study was conducted at the Aichi Cancer Center in Nagoya, Japan from 1988-1991. This study compared 668 histologically confirmed gastric cancer cases [123 cardia, 218 middle (body), 256 antrum, and 71 unclassified] with 668 controls using a common questionnaire about life-styles as related to smoking, drinking, dietary habits and frequency of food intake. Controls were selected from among outpatients of the same hospital. Controls free of cancer and other specific diseases were matched with cases for sex, age (within 2 years), and time of hospital visit (within 2 months). A Western-style breakfast decreased the risk of antrum cancer, while consumption of greasy food increased the risk of cardia cancer. Fresh vegetables decreased the risk of cancer in both cardia and antrum. Habitual smoking is associated with increased risk of gastric cancer and it is more prominent in cardia cancer, especially in those who are drinkers. Results obtained from this study suggest that risk factors and relative risks of gastric cancer varied by subsite to a considerable degree. Furthermore, the joint effect of smoking and drinking may play an important role in the development of gastric cancer, especially of cardia cancer.

Alcohol Drinking↗

The use of a human dura mater allograft for the repair of a contaminated abdominal wall defect: report of a case.

A case report of an infected full-thickness abdominal wall defect treated successfully with a human dura mater allograft is presented. A review of the literature and a discussion of prosthetic abdominal wall repair is also included. A 46-year-old woman presented with multiple small bowel perforations and a large abdominal wall defect due to a motor vehicle collision. A gamma-irradiated human dura mater prosthesis was used to repair the large abdominal wall defect which had been infected by a jejunal fistula. After more than 4 years of follow-up, the patient is free of complications, including wound infection, herniation, and ileus. The human dura mater allograft is thus considered to be a useful prosthesis for repairing potentially infected wounds.

Abdominal Muscles↗

Leaching and cytotoxicity of formaldehyde and methyl methacrylate from acrylic resin denture base materials.

Acrylic resin dentures have the potential to elicit irritation, inflammation, and an allergic response of the oral mucosa. Studies of substances leachable from acrylic resins, their cytotoxicity to cultured cells, and means of reducing their leaching were systematically conducted. Under in vivo and in vitro conditions, formaldehyde and methyl methacrylate were significantly leached into human saliva and saliva-substitute buffer, especially from autopolymerized resins. Both leachable substances showed cytotoxic potentials in the range of their leaching concentrations. Formaldehyde was cytotoxic at lower concentrations than methyl methacrylate. Preleaching in water reduced subsequent leaching of both formaldehyde and methyl methacrylate, and the amount of reduction depended on an increase in the preleaching temperatures. Immersion of acrylic resin dentures in hot water (50 degrees C) before insertion is recommended, especially for autopolymerized resins used either for rebasing or as denture base materials, to minimize the risk of adverse reactions in patients who wear acrylic resin dentures.

Cell Count↗

Case-control studies: matched controls or all available controls?

In order to realize the variation in the estimate of the odds ratio from case-control studies, results from individually matched sampling were compared with those from the analysis based on a large number of controls. The subjects were selected from those who visited Aichi Cancer Center Hospital from 1988 to 1990. Cases consisted of 251 male lung cancer patients aged 40-79 years. Age and year of visit matched controls were sampled independently 100 times and 5000 times from non-cancer male outpatients (cases to controls ratio: 1:1, 1:2, 1:3, and 1:4). As unmatched controls, all male non-cancer outpatients aged 40-79 years (4100 patients) were used. The smoking habit was adopted as an exposure variable. As logically expected, analysis based on 4100 male controls gave a steadier estimate than the matched analyses examined here, indicating that a matched sampling is not recommended when a large number of controls are available.

Adult↗

A simple surgical atrial septectomy for complex congenital heart disease.

A simple method of surgical atrial septectomy using a rongeur (Kerrison bone-cutting forceps), which is used in neurosurgery, is described. The closed rongeur is inserted into the left atrium through the right atrial appendage and the atrial septum. Then it is opened and the edge of the atrial septal defect and/or patent foramen ovale can be hooked by pulling slowly. The rongeur is then tightly closed again and pulled out together with the resected atrial specimen. This technique is safer and simpler than the Blalock-Hanlon technique or atrial septectomy with extra-corporeal circulation for older infants in whom balloon atrial septostomy is difficult.

Heart Defects, Congenital↗