Biomedical subjects

T Shimakawa

Publications and source records attributed to T Shimakawa.

At least 19 recordsLinked to original sources

PubMed2000

Trends in plasma cholesterol levels in the atherosclerosis risk in communities (ARIC) study.

BACKGROUND: Data from the Atherosclerosis Risk in Communities (ARIC) cohort study were examined both cross-sectionally and intraindividually to confirm recent findings from population-based studies showing a decline in total cholesterol (TC) levels in the United States. METHODS: For the cross-sectional analysis, mean plasma TC levels from 15,792 participants aged 45-64 at baseline visit, and who were selected randomly from four U.S. communities, were examined for each year covered by the first cohort visit (1987, 1988, and 1989). Ninety-three percent of the cohort participants returned for the follow-up visit (1990, 1991, and 1992), and were included in the assessment of intraindividual TC trends. RESULTS: Both mean TC and prevalence of hypercholesterolemia (defined as plasma cholesterol concentration >/=240 mg/dl) consistently declined over the 3 years covered by visit 1 for all age-gender-race groups. For 1987, 1988, and 1989, mean TC values (mg/dl) were, respectively, 220.3, 216.7, and 214.1 (annual average change, -1.4%, P < 0.001). For these same years, hypercholesterolemia prevalence rates were 30. 0, 27.8, and 25.3% (annual average change, -7.8%, P < 0.001). The mean plasma TC also decreased within individuals between the two visits across race, gender, and age decade categories. With the exception of black men, this decline was more marked for older than younger subjects, but no consistent differences were seen between the racial groups. However, in whites, decreases were greater for men than for women. Expected results were seen when these changes were correlated with changes in cardiovascular risk factors between the two visits. CONCLUSION: The current study results are consistent with those of previous studies, and confirm the notion that preventive programs appear to be effective in reducing mean population TC levels.

Arteriosclerosis↗

PubMed2000

Suppression of cellular immunity by surgical stress.

BACKGROUND: Suppression of cellular immunity is one of the host responses to surgical stress. In cancer patients this immunosuppression may accelerate the growth and metastasis of residual cancer cells, so it is desirable to restrict immunosuppression by surgical stress to a minimum. However, the extent and duration of immunosuppression caused by operations on gastrointestinal cancer, as well as the mechanisms involved, have not been determined. METHODS: To clarify these points, we investigated immunocyte function and measured the blood levels of hormones, cytokines, and acute phase reactants from before to after operation in 20 patients with stage I gastrointestinal cancer. RESULTS: In patients exposed to surgical stress, peripheral blood lymphocyte numbers and function were suppressed until at least 2 weeks postoperatively. This immunosuppression was mainly due to a decrease of helper-inducer T cells, cytotoxic T cells, natural killer cells, and interleukin-2 receptor-positive cells, as well as an increase of suppressor T cells. In addition, hypersecretion of cortisol and overproduction of immunosuppressive acidic protein were observed. CONCLUSIONS: Cellular immunosuppression by surgical stress was mainly due to an increase of lymphocyte subsets that depress cellular immunity coupled with a decrease of the subsets that promote it. Overproduction of cortisol and immunosuppressive acidic protein in response to surgical stress may play an important role in the development of immunosuppression.

Acute-Phase Proteins↗

PubMed1999

Clinical evaluation of endoscopic injection sclerotherapy using n-butyl-2-cyanoacrylate for gastric variceal bleeding.

BACKGROUND: Emergency endoscopic injection sclerotherapy (EIS) has been applied to the initial treatment of gastric variceal bleeding and various methods have been attempted. METHODS: Emergency EIS was performed on 38 patients with gastric variceal bleeding using either the ethanolamine oleate (EO) method or n-butyl-2-cyanoacrylate (Histoacryl) method and the outcome was compared. RESULTS: Complete haemostasis was defined as continuous haemostasis lasting for 14 days or more. Complete haemostasis was achieved in 52.4% of patients in the EO method versus 100% of those treated with the Histoacryl method, a significant difference, suggesting that the Histoacryl method was superior for achieving haemostasis in an emergency. The cumulative non-bleeding rate was also significantly higher in patients treated with Histoacryl, indicating the durability of haemostasis. There were no serious complications in patients who received either method of sclerotherapy. Post-EIS surgery was required in 42.8% of patients treated with EO, while no surgery was required in those treated with Histoacryl, supporting the greater haemostatic effect of Histoacryl. Although there was no significant difference in the cumulative survival rates of patients treated by these two methods, death from haemorrhage was avoided by using Histoacryl. CONCLUSIONS: Based on these results, the Histoacryl method is thought to be the initial treatment of choice for gastric variceal bleeding, because it achieved superior haemostasis compared with EO and death by haemorrhage was avoided.

Emergencies↗

PubMed1998

Provitamin A carotenoid intake and carotid artery plaques: the Atherosclerosis Risk in Communities Study.

We examined the cross-sectional association between intake of carotenoids with provitamin A activity and carotid artery plaques in 12,773 participants of the Atherosclerosis Risk in Communities Study aged 45-64 y. Usual diet was assessed with a 66-item food-frequency questionnaire. Plaques were examined by B-mode ultrasound of multiple carotid artery segments. In both women and men, those in the highest quintile of carotenoid consumption had a lower prevalence of plaques (women, 25.4%; men, 36.0%) than those in the lowest quintile of carotenoid consumption (women, 29.3%; men, 39.8%). The prevalence odds ratios contrasting extreme intake quintiles were 0.82 (95% CI: 0.70, 0.97) in women and 0.85 (95% CI: 0.72, 1.01) in men. The associations diminished slightly after potential confounders were adjusted for. In women, the inverse association was particularly strong for current smokers (adjusted odds ratio contrasting extreme quintiles: 0.67; 95% CI: 0.45, 0.98). In men, no such effect modification by smoking was seen. The inverse association was somewhat stronger in men aged 55-64 y than in those aged 45-54 y, whereas age made little difference in women. These findings, together with previous findings that carotenoid intake was unrelated to average carotid artery wall thickness, suggest that carotenoids may exert their influence later rather than earlier in the atherosclerotic process, and support the hypothesis that carotenoids or other plant-derived compounds may play a role in preventing arterial plaque formation.

Arteriosclerosis↗

PubMed1998

[Studies on pulmonary and systemic hemodynamic changes after transjugular intrahepatic portosystemic shunt (TIPS)].

In 10 patients who underwent transjugular intrahepatic portosystemic shunt (TIPS) at our institution, postoperative pulmonary and systemic hemodynamic changes were compared with those before the procedure. After TIPS, right atrial and pulmonary capillary wedge pressures, cardiac output, and cardiac index increased significantly, and there was a significant decrease in total peripheral resistance. Thus, systemic hemodynamic changes showed evidence of a more hyperdynamic circulation. In addition, right ventricular end-diastolic volume index was significantly increased and this increase was persistent, with maintained right heart strain. With respect to pulmonary hemodynamics, alveolar arterial oxygen difference and right-to-left shunt increased significantly, along with a significant decrease in arterio-venous oxygen content difference, which indicated impairment of pulmonary diffusing capacity. These findings suggest that preoperative evaluation of the cardiac reserve and pulmonary function is important before performing TIPS. After TIPS, patients should be followed carefully because postoperative heart failure or pulmonary edema may occur.

Aged↗

PubMed1997

Vitamin intake: a possible determinant of plasma homocyst(e)ine among middle-aged adults.

PURPOSE: Many epidemiologic studies have identified elevated plasma homocyst(e)ine as a risk factor for atherosclerosis and thromboembolic disease. To examined the relationship between vitamin intakes and plasma homocyst(e)ine, we analyzed dietary intake data from a case-control study of 322 middle-aged individuals with atherosclerosis in the carotid artery and 318 control subjects without evidence of this disease. METHODS: All of these individuals were selected from a probability sample of 15,800 men and women who participated in the Atherosclerosis Risk in Communities (ARIC) Study. RESULTS: Plasma homocyst(e)ine was inversely associated with intakes of folate, vitamin B6, and vitamin B12 (controls only for this vitamin)--the three key vitamins in homocyst(e)ine metabolism. Among nonusers of vitamin supplement products, on average each tertile increase in intake of these vitamins was associated with 0.4 to 0.7 mumol/L decrease in plasma homocyst(e)ine. An inverse association of plasma homocyst(e)ine was also found with thiamin, riboflavin, calcium, phosphorus, and iron. Methionine and protein intake did not show any significant association with plasma homocyst(e)ine. CONCLUSIONS: In almost all analyses, cases and controls showed similar associations between dietary variables and plasma homocyst(e)ine. Plasma homocyst(e)ine among users of vitamin supplement products was 1.5 mumol/L lower than that among nonusers. Further studies to examine possible causal relationships among vitamin intake, plasma homocyst(e)ine, and cardiovascular disease are needed.

Analysis of Variance↗

PubMed1996

Relation of hormone-replacement therapy to measures of plasma fibrinolytic activity. Atherosclerosis Risk in Communities (ARIC) Study Investigators.

BACKGROUND: The mechanisms by which replacement hormones may reduce the risk of coronary heart disease are not fully understood. Of specific interest is a potential effect of replacement hormones on plasma fibrinolytic activity, a putative determinant of thrombotic events. METHODS AND RESULTS: We investigated the relation of current use of replacement hormones to three measures of plasma fibrinolytic activity: tissue-type plasminogen activator (TPA) antigen, plasminogen activator inhibitor-1 (PAI-1) antigen, and D-dimer. The sample was composed of 288 women, free of clinical cardiovascular disease, who were selected for a case-control study of atherosclerosis: 142 women with ultrasonographic evidence of carotid intimal-medial thickening (cases) and 146 control subjects. Twenty percent (59 women) reported current use of replacement hormones. TPA antigen and PAI-1 antigen were highly correlated with each other (r = .67), whereas D-dimer correlated only weakly with TPA or PAI-1. Compared with nonusers, current users of replacement hormones had lower mean levels of TPA and PAI-1 antigens, suggesting enhanced fibrinolytic potential. In the entire sample, the multivariate-adjusted geometric mean values of TPA antigen were 6.3 and 7.3 ng/mL among current users and nonusers, respectively (P = .01); the corresponding values for PAI-1 antigen were 6.1 and 7.5 ng/mL (P = .13). These results were generally consistent for both atherosclerosis cases and their control subjects. D-dimer levels were lower in current hormone users than in nonusers, but the difference was not statistically significant (P > .15) in any of the analyses. CONCLUSIONS: The use of replacement hormones appears to be associated with enhancement of endogenous fibrinolytic potential. Enhanced plasma fibrinolytic activity among hormone users may explain, in part, the inverse association between hormone replacement therapy and coronary heart disease.

Alcohol Drinking↗

PubMed1995

Dietary antioxidants and carotid artery wall thickness. The ARIC Study. Atherosclerosis Risk in Communities Study.

BACKGROUND: Evidence that dietary antioxidants may prevent atherosclerotic disease is growing. The relationship between the intake of dietary and supplemental vitamin C, alpha-tocopherol, and provitamin A carotenoids and average carotid artery wall thickness was studied in 6318 female and 4989 male participants 45 to 64 years old int he Atherosclerosis Risk in Communities Study. METHODS AND RESULTS: Intake was assessed by use of a 66-item semiquantitative food-frequency questionnaire. Carotid artery intima-media wall thickness was measured as an indicator of atherosclerosis at multiple sites with B-mode ultrasound. Among men and women > 55 years old who had not recently begun a special diet, there was a significant inverse relationship between vitamin C intake and average artery wall thickness adjusted for age, body mass index, fasting serum glucose, systolic and diastolic blood pressures, HDL and LDL cholesterol, total caloric intake, cigarette use, race, and education (test for linear trend across quintiles of intake, P = .019 for women and P = .035 for men). An inverse relationship was also seen between wall thickness and alpha-tocopherol intake but was significant only in women (test for linear trend, P = .033 for women and P = .13 for men). There was a significant inverse association between carotene intake and wall thickness in older men (test for linear trend, P = .015), but the association weakened after adjustment for potential confounders. No significant relationships were seen in participants < 55 years old. CONCLUSIONS: These data provide limited support for the hypothesis that dietary vitamin C and alpha-tocopherol may protect against atherosclerotic disease, especially in individuals > 55 years old.

Antioxidants↗

PubMed1995

[A case of advanced esophageal cancer made resectable by preoperative combination therapy with 5-FU and CDDP].

The authors experienced a case of advanced esophageal cancer made resectable by combination therapy with 5-FU and CDDP as a neoadjuvant chemotherapy. The patient was a 69-year-old-man suffering from esophageal cancer of A3.N4 (+).Pl0.M0 at stage IV. At this case was diagnosed to be radically unresectable, this form of combination therapy was used. The patient showed PR after 2 courses and the operation could then be conducted. The intraoperative findings revealed fibrous fusion of tumor with the aorta, but no direct invasion. The metastatic lymph nodes were necrotized and reduced. It was evaluated as Grade 3 in accordance with the "Histologic criteria for the effects of anticancer chemotherapy." The postoperative course was favorable without recurrence. This therapy caused no adverse reactions and seems effective as a neoadjuvant chemotherapy for advanced esophageal cancer.

Aged↗

PubMed1995

[Study on pyrimidine nucleoside phosphorylase (PyNPase) activity in resected tissues of patients with gastric cancer].

Pyrimidine nucleoside phosphorylase (PyNPase) activity was measured in gastric cancer tissue from 25 patients who underwent resections of gastric cancer. The relation between the activity and host and tumor factors in gastric cancer was studied, and the following results were obtained. 1. PyNPase activity was 128.3 +/- 99.5 in cancer tissue and 37.2 +/- 23.1 in non-cancer tissue. The level was significantly higher in cancer tissue (p < 0.0001). 2. With respect to host factors, the PyNPase activity tended to be high in patients in whom cell-mediated immune response was maintained. 3. With respect to tumor factors, the values tended to be high in patients who were positive for lymph vessel and venous invasion, and positive for lymph node metastasis. 5'-deoxy-5-fluorouridine(5'-DFUR) is an anticancer agent which manifests antitumor effects when it is transformed into 5-FU by PyNPase. When this agent is administered to gastric cancer patients, it can be expected to be more effective in the above types of patients because of its characteristics.

Adult↗

PubMed1995

[Portal hemodynamic changes from TIPS--evaluation with pulse Doppler method].

Transjugular intrahepatic portosystemic shunt (TIPS) was applied in three patients with Child C liver cirrhosis. Portal venous pressure was reduced by an average of 10.7 mmHg, and results such as the disappearance of esophageal varices and reduction in ascites were obtained. The portal hemodynamics of these three patients was observed before and after TIPS using the pulse Doppler method. When portal hemodynamics in the main portal vein was examined before TIPS, it was found that the mean blood flow velocity had decreased, the blood flow volume was reduced and the cross-sectional area of the vein had increased. The congestion index was high and there was definite congestion of the portal venous system. After TIPS, the blood flow velocity and volume increased, the cross-sectional area of the vein was reduced and the congestion index was lower. Congestion of the portal venous system was improved in these three patients and the clinical efficacy of TIPS was proven by these results. If the stent can be detected sonographically, stent patency is easily confirmed with the pulse Doppler method which is usefull examination technique for follow-up of patients undergoing TIPS.

Aged↗

PubMed1995

[Influence of intratumor administration of OK-432 on the tumor selectivity of 5'-DFUR].

The influence of intratumor administration of OK-432 on the tumor-selective antitumor effect of 5'-DFUR was studied in 49 patients with advanced gastric cancer. The patients were divided into 4 groups that received oral 5'-DFUR, intratumor OK-432, oral 5'-DFUR plus intratumor and intracutaneous OK-432, or no therapy before operation. Using surgical specimens, the PyNPase activity and 5-FU content were measured, and the localization of PyNPase was determined immunohistologically. The results were as follows: 1) 5'-DFUR therapy decreased intratumor PyNPase activity whereas administration of OK-432 increased it. 2) PyNPase activity was higher in cancer tissue than in normal tissue for all groups. 3) The 5-FU content of cancer tissue was higher in patients receiving OK-432 plus 5'-DFUR than in patients receiving 5'-DFUR alone. 4) In the resected tumors, PyNPase was mainly localized in the cancer cells of some patients and in the stromal cells of others. Thus, the localization of PyNPase showed two major patterns.

Antineoplastic Agents↗

PubMed1994

Dietary fat intake and carotid artery wall thickness: the Atherosclerosis Risk in Communities (ARIC) Study.

Associations between atherosclerosis and dietary fat and cholesterol have been demonstrated in numerous animal experiments. The relation between these dietary components and atherosclerosis has not previously been reported in a population-based study among human beings. The associations of dietary fat and cholesterol with carotid artery wall thickness (atherosclerosis) were investigated in a population-based study, the Atherosclerosis Risk in Communities (ARIC) Study, from 1987 to 1989. Participants were 2,095 black women, 5,146 white women, 1,318 black men and 4,589 white men, aged 45-64 years, recruited from four US communities: Jackson, Mississippi; Forsyth County, North Carolina; Washington County, Maryland; and Minneapolis, Minnesota. Habitual diet was assessed with a food frequency questionnaire. Wall thickness was measured with B-mode ultrasound. After adjustment for age and energy intake, animal fat, saturated fat, monounsaturated fat, cholesterol, and Keys' score were positively related to wall thickness, while vegetable fat and polyunsaturated fat were inversely related to wall thickness. These associations persisted after further adjustment for smoking and hypertension and were consistent across the four race and sex groups. Thus, elements of habitual dietary intake were consistently associated with carotid artery wall thickness, compatible with their putatively atherogenic and antiatherogenic properties.

Black or African American↗

PubMed1994

Dietary intake patterns and sociodemographic factors in the atherosclerosis risk in communities study. ARIC Study Investigators.

BACKGROUND: Comprehensive and up-to-date data on differences in dietary intake according to various sociodemographic factors are needed to understand the potential impact of dietary factors on disease risks in the United States. METHODS: Usual dietary intake assessed by a food frequency questionnaire was examined in relation to race, sex, and educational attainment using baseline data obtained from randomly selected samples of 15,800 middle-aged black and white men and women who participated in the Atherosclerosis Risk in Communities Study. RESULTS: In almost all comparisons, higher educational attainment was associated with recommended dietary intake patterns--lower per energy intakes of meats, eggs, chicken with skin, and whole milk and higher intakes of fruits, vegetables, fish, chicken without skin, and low-fat milk. As expected from these food intake patterns, higher educational attainment was associated with lower intakes of saturated fatty acid and cholesterol and with higher intakes of dietary fiber and various micronutrients. Compared with women's diets, men's diets were slightly more atherogenic (in whites only) based upon Keys score and had lower micronutrient levels. Although there were large differences in the food intakes between blacks and whites, the differences in nutrient intakes were generally smaller. However, intakes of cholesterol and vitamin A were somewhat higher and intakes of saturated fatty acid, calcium, and potassium were lower among blacks than in whites. CONCLUSIONS: This community-based study clearly demonstrated that regardless of race and sex, high educational attainment is associated with recommended dietary intake patterns. Continuing efforts to improve general educational level and to promote healthy dietary habits among those with low socioeconomic status are warranted.

Black or African American↗

PubMed1994

Does dietary vitamin A protect against airway obstruction? The Atherosclerosis Risk in Communities (ARIC) Study Investigators.

A recent report based on data from the first National Health and Nutrition Examination Survey suggested that low intake of vitamin A may be associated with a greater risk of airway obstruction. We attempted to replicate these findings in a population-based sample of middle-aged adults (n = 15,743) who participated in the baseline examination of the Atherosclerosis Risk in Communities (ARIC) Study. Vitamin A intake was estimated from a 66-item food frequency questionnaire, and the presence of airway obstruction was determined by spirometry. Although airway obstruction was associated in ARIC with well-established risk factors such as age, sex, and smoking, there was little evidence for a role of vitamin A. With only one exception, vitamin A intake was unrelated to airway obstruction in all smoking categories using either categorical or continuous measures of lung function (FEV1, FVC, FEV1/FVC). Only among current smokers in the upper tertile of lifetime cigarette smoking (> 41 pack-years) was the odds ratio of having airway obstruction for the lowest quartile of vitamin A intake compared with the highest quartile elevated (1.7 [95% confidence interval 1.1 to 2.7]). Despite some biological plausibility that vitamin A intake may prevent obstructive lung disease, the inability to demonstrate association in a larger population study, with better estimation of usual dietary intake, casts doubt on the existence of causal relationship.

Airway Obstruction↗

PubMed1993

Usual dietary intake and hemoglobin A1 level in patients with insulin-dependent diabetes.

OBJECTIVE: To explore epidemiologic evidence for the relationship between dietary intake and glycemic control. DESIGN/SUBJECTS: We examined usual dietary intake, assessed by a food frequency questionnaire, from a random sample (n = 136) of patients who had had insulin-dependent diabetes mellitus for 15 to 21 years. RESULTS: In men, absolute intakes of energy, carbohydrate, protein, fat, and dietary fiber were positively correlated with hemoglobin A1 (HbA1) (P < .05); Spearman correlation coefficients (rs) were .28, .22, .28, .34, and .25, respectively. In women, the correlations were weaker and not significant; rs values were .18, .13, .17, .19, and .16, respectively. When these nutrients were expressed as a percentage of energy or as an amount per 1,000 kcal, only percentage of energy from fat showed a significant association with HbA1--but only in men (rs = .23 for men and .02 for women). Adjustment for body weight, insulin dose, and physical activity using multiple regression analysis did not change the relationship between HbA1 and intakes of energy and fat. Sucrose and alcohol intakes did not show any association with HbA1. CONCLUSIONS: Among men with insulin-dependent diabetes mellitus, the major dietary correlates of poor glycemic control were high intake of energy and percentage of energy from fat. Further investigation is needed to confirm this relationship of energy, fat, and glycemic control.

Adult↗

PubMed1993

Relationship between hemoglobin and cardiovascular risk factors in young adults.

To understand mechanisms of association between hemoglobin and cardiovascular disease (CVD), the relationships between hemoglobin and CVD risk factors were examined in 5115 black and white men and women who participated in the Coronary Artery Risk Development in Young Adults (CARDIA) Study. Hemoglobin was higher in men than women, whites than blacks, and smokers than non-smokers (p < 0.001). After adjusting for age, body mass index, current smoking status, and clinical center, hemoglobin correlated with diastolic blood pressure (0.11 < or = r < or = 0.22, p < 0.001) and plasma total cholesterol (0.08 < or = r < or = 0.11, p < 0.01) in all four race-sex groups and with systolic blood pressure in all but black women (0.07 < or = r < or = 0.13, p < 0.05). Among other factors possibly related to CVD risk, only serum albumin and white blood cell count showed significant correlations with hemoglobin in all groups (0.19 < or = r < or = 0.27, 0.07 < or = r < or = 0.18, respectively). These findings suggest that an association of hemoglobin with CVD risk factors may explain the association of hemoglobin with CVD.

Adult↗

PubMed1993

Identification of amino acid residues responsible for the changes of absorption and fluorescence spectra on the binding of subtilisin BPN' and Streptomyces subtilisin inhibitor.

An ultraviolet absorption difference spectrum characteristic of the ionization change of a tyrosyl residue was observed on the binding of subtilisin BPN' with Streptomyces subtilisin inhibitor (SSI) at alkaline pH. This difference spectrum was considered to be induced by a pKa shift (from 9.7 to > or = 11.5) of a tyrosyl residue of subtilisin BPN' in the interaction with carboxyls of SSI [Inouye et al. (1979) J. Biochem. 85, 1115-1126]. In the present paper, the tyrosyl residue in subtilisin BPN' and the carboxyls in SSI were identified by analyzing the difference spectrum using mutants of subtilisin BPN' and SSI: naturally occurring mutants and those prepared by site-directed and cassette mutagenesis. The difference spectrum disappeared on the binding of a mutant subtilisin BPN' of which Tyr104 was replaced by Phe (S-BPN'Y104F) and SSI at pH 9.8. The magnitude of the absorption difference was much smaller when subtilisin BPN' was bound with a mutant SSI of which both Glu67 and Asp68 were replaced by Gly than with the wild-type SSI. These lines of evidence indicated that the difference spectrum was caused by Tyr104 of subtilisin BPN' interacting with Glu67 and Asp68 of SSI. The binding of subtilisin BPN' and SSI is accompanied by an increase of tryptophan fluorescence, which is pH-dependent in the range of pH 7-11 [Uehara et al. (1978) J. Biochem. 84, 1195-1202]. In the present study, this pH-dependence of the fluorescence diminished when SSI bound with S-BPN'Y104F. This suggested that the fluorescence increase was due to Trp106 of subtilisin BPN' and was influenced by the ionization of Tyr104.

Amino Acids↗