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Validity of a selective recall method for assessing water intake and its relationship with hydration status.
Uchida, T, Nakamura, Y, Tanaka, H, Nakamura, S, Okamura, T, Watanabe, H, Murayama, N
European review for medical and pharmacological sciences. 2021;(21):6623-6632
Abstract
OBJECTIVE We previously established a descriptive dietary record method that accurately quantifies habitual water intake from food and beverages, to ascertain the relationship between water intake and health. Here, we verified the validity of a selective recall method, which is easy for users to answer and analyze. PATIENTS AND METHODS Japanese men and women aged 20-44 years (n = 16) and 45-64 years (n = 16) participated over three working days and one non-working day. The day following each of the surveyed days, participants collected their first morning urine for urinalysis and completed a selective recall and descriptive dietary record questionnaire. RESULTS The two methods of determining water intake were positively correlated (r = 0.94, p < 0.0001). Water intake volumes from non-alcoholic beverages (r = 0.94, p < 0.0001), alcoholic beverages (r = 1.00, p < 0.0001), and food (r = 0.72, p < 0.0001), calculated using the two methods, exhibited strong correlation. No correlation was observed between urinalysis parameters and total water intake. A significant, negative correlation was observed between urine osmolarity and total water intake in men (r = -0.55, p = 0.0011) and women (r = -0.51, p = 0.0032) aged 20-44 years. CONCLUSIONS Selective recall is a valid method for assessing water intake from food and beverages.
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Subacute Ingestion of Caffeine and Oolong Tea Increases Fat Oxidation without Affecting Energy Expenditure and Sleep Architecture: A Randomized, Placebo-Controlled, Double-Blinded Cross-Over Trial.
Zhang, S, Takano, J, Murayama, N, Tominaga, M, Abe, T, Park, I, Seol, J, Ishihara, A, Tanaka, Y, Yajima, K, et al
Nutrients. 2020;(12)
Abstract
Ingesting oolong tea or caffeine acutely increases energy expenditure, and oolong tea, but not caffeine, stimulates fat oxidation. The acute effects of caffeine, such as increased heart rate and interference with sleep, diminish over 1-4 days, known as caffeine tolerance. During each 14-day session of the present study, 12 non-obese males consumed oolong tea (100 mg caffeine, 21.4 mg gallic acid, 97 mg catechins and 125 mg polymerized polyphenol), caffeine (100 mg), or placebo at breakfast and lunch. On day 14 of each session, 24-h indirect calorimetry and polysomnographic sleep recording were performed. Caffeine and oolong tea increased fat oxidation by ~20% without affecting energy expenditure over 24-h. The decrease in the respiratory quotient by oolong tea was greater than that by caffeine during sleep. The effect of oolong tea on fat oxidation was salient in the post-absorptive state. These findings suggest a role of unidentified ingredients in oolong tea to stimulate fat oxidation, and this effect is partially suppressed in a postprandial state. Two weeks of caffeine or oolong tea ingestion increased fat oxidation without interfering with sleep. The effects of subacute ingestion of caffeine and oolong tea differed from the acute effects, which is a particularly important consideration regarding habitual tea consumption.
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3.
Effect of Increased Daily Water Intake and Hydration on Health in Japanese Adults.
Nakamura, Y, Watanabe, H, Tanaka, A, Yasui, M, Nishihira, J, Murayama, N
Nutrients. 2020;(4)
Abstract
Increased hydration is recommended as healthy habit with several merits. However, supportive data are sparse. To assess the efficacy of increased daily water intake, we tested the effect of water supplementation on biomarkers in blood, urine, and saliva. Twenty-four healthy Japanese men and 31 healthy Japanese women with fasting blood glucose levels ranging from 90-125 mg/dL were included. An open-label, two-arm, randomized controlled trial was conducted for 12 weeks. Two additional 550 mL bottles of water on top of habitual fluid intake were consumed in the intervention group. The subjects drank one bottle of water (550 mL) within 2 h of waking, and one bottle (550 mL) 2 h before bedtime. Subjects increased mean fluid intake from 1.3 L/day to 2.0 L/day, without changes in total energy intake. Total body water rate increased with associated water supplementation. There were no significant changes in fasting blood glucose and arginine vasopressin levels, but systolic blood pressure was significantly decreased in the intervention group. Furthermore, water supplementation increased body temperature, reduced blood urea nitrogen concentration, and suppressed estimated glomerular filtration rate reduction. Additionally, existence of an intestinal microbiome correlated with decreased systolic blood pressure and increased body temperature. Habitual water supplementation after waking up and before bedtime in healthy subjects with slightly elevated fasting blood glucose levels is not effective in lowering these levels. However, it represents a safe and promising intervention with the potential for lowering blood pressure, increasing body temperature, diluting blood waste materials, and protecting kidney function. Thus, increasing daily water intake could provide several health benefits.
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Green Tea Intake and Risks for Dementia, Alzheimer's Disease, Mild Cognitive Impairment, and Cognitive Impairment: A Systematic Review.
Kakutani, S, Watanabe, H, Murayama, N
Nutrients. 2019;11(5)
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Around 50 million people worldwide suffer from dementia, with 10 million new cases being diagnosed every year. Diet may play a role in the prevention of dementia. In this systematic review, the authors reviewed eight previous studies examining the effects of green tea on dementia. Six of the eight studies supported a preventative effect of green tea intake. The authors suggested that green tea might positively influence biological mechanisms such as oxidative stress, inflammation, accumulation of plaques in the brain and the maintenance of healthy blood vessels. The authors concluded that green tea intake might reduce the risk for dementia, Alzheimer's disease, mild cognitive impairment, or cognitive impairment, but further studies are needed.
Abstract
Dementia has become a major issue that requires urgent measures. The prevention of dementia may be influenced by dietary factors. We focused on green tea and performed a systematic review of observational studies that examined the association between green tea intake and dementia, Alzheimer's disease, mild cognitive impairment, or cognitive impairment. We searched for articles registered up to 23 August 2018, in the PubMed database and then for references of original articles or reviews that examined tea and cognition. Subsequently, the extracted articles were examined regarding whether they included original data assessing an association of green tea intake and dementia, Alzheimer's disease, mild cognitive impairment, or cognitive impairment. Finally, we included three cohort studies and five cross-sectional studies. One cohort study and three cross-sectional studies supported the positive effects of green tea intake. One cohort study and one cross-sectional study reported partial positive effects. The remaining one cohort study and one cross-sectional study showed no significant association of green tea intake. These results seem to support the hypothesis that green tea intake might reduce the risk for dementia, Alzheimer's disease, mild cognitive impairment, or cognitive impairment. Further results from well-designed and well-conducted cohort studies are required to derive robust evidence.
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Localized amyloidosis of the stomach mimicking a superficial gastric cancer.
Kagawa, M, Fujino, Y, Muguruma, N, Murayama, N, Okamoto, K, Kitamura, S, Kimura, T, Kishi, K, Miyamoto, H, Uehara, H, et al
Clinical journal of gastroenterology. 2016;(3):109-13
Abstract
A 73-year-old man was referred to our hospital for further examination of a depressed lesion in the stomach found by cancer screening gastroscopy. A barium upper gastrointestinal series showed an area of irregular mucosa measuring 15 mm on the anterior wall of the gastric body. Esophagogastroduodenoscopy revealed a 15 mm depressed lesion on the anterior wall of the lower gastric body. We suspected an undifferentiated adenocarcinoma from the appearance and took some biopsies. However, histology of the specimens revealed amyloidal deposits in the submucosal layer without malignant findings. Congo red staining was positive for amyloidal protein and green birefringence was observed under polarized light microscopy. Congo red staining with prior potassium permanganate incubation confirmed the light chain (AL) amyloid type. There were no amyloid deposits in the colon or duodenum. Computed tomography of the chest, abdomen, and pelvis showed no remarkable findings. Thus, this case was diagnosed as a localized gastric amyloidosis characterized by AL type amyloid deposition in the mucosal or submucosal layer. As the clinical outcome of gastric AL amyloidosis seems favorable, this case is scheduled for periodic examination to recognize potential disease progression and has been stable for 2 years.
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Regioselective hydroxylation of steroid hormones by human cytochromes P450.
Niwa, T, Murayama, N, Imagawa, Y, Yamazaki, H
Drug metabolism reviews. 2015;(2):89-110
Abstract
This article reviews in vitro metabolic activities [including Michaelis constants (Km), maximal velocities (Vmax) and Vmax/Km] and drug-steroid interactions [such as induction and cooperativity (activation)] of cytochromes P450 (P450 or CYP) in human tissues, including liver and adrenal gland, for 14 kinds of endogenous steroid compounds, including allopregnanolone, cholesterol, cortisol, cortisone, dehydroepiandrosterone, estradiol, estrone, pregnenolone, progesterone, testosterone and bile acids (cholic acid). First, we considered the drug-metabolizing P450s. 6β-Hydroxylation of many steroids, including cortisol, cortisone, progesterone and testosterone, was catalyzed primarily by CYP3A4. CYP1A2 and CYP3A4, respectively, are likely the major hepatic enzymes responsible for 2-/4-hydroxylation and 16α-hydroxylation of estradiol and estrone, steroids that can contribute to breast cancer risk. In contrast, CYP1A1 and CYP1B1 predominantly metabolized estrone and estradiol to 2- and 4-catechol estrogens, which are endogenous ultimate carcinogens if formed in the breast. Some metabolic activities of CYP3A4, including dehydroepiandrosterone 7β-/16α-hydroxylation, estrone 2-hydroxylation and testosterone 6β-hydroxylation, were higher than those for polymorphically expressed CYP3A5. Next, we considered typical steroidogenic P450s. CYP17A1, CYP19A1 and CYP27A1 catalyzed steroid synthesis, including hydroxylation at 17α, 19 and 27 positions, respectively. However, it was difficult to predict which hepatic drug-metabolizing P450 or steroidogenic P450 will be mainly responsible for metabolizing each steroid hormone in vivo based on these results. Further research is required on the metabolism of steroid hormones by various P450s and on prediction of their relative contributions to in vivo metabolism. The findings collected here provide fundamental and useful information on the metabolism of steroid compounds.
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Effects of Socioeconomic Status on Nutrition in Asia and Future Nutrition Policy Studies.
Murayama, N
Journal of nutritional science and vitaminology. 2015;:S66-8
Abstract
Evidence of health disparities has been reported around the world. One of the intermediate factors between socioeconomic status (SES) and health is nutrition. Many studies reported socioeconomically disadvantaged people had more risk of obesity and lifestyle-related diseases than others in western society. Micronutrient intake affected by SES, but little evidence indicates that SES affects either energy intake or the macronutrient composition of the diet in western countries. In contrast, there is not enough evidence of a consistent relationship between SES and nutrition in Asian countries at present. The present status of nutrition disparities in Asia is considered to vary by economic level of the country. For developing countries in Asia, India and Vietnam, SES associates with BMI positively in women. For relatively developed countries in Asia, Korea and Japan, SES associates with BMI negatively in women. Low SES groups consume more carbohydrate, and less protein and fat, so not only micronutrient but also macronutrient intake is affected by SES both in developing and in developed Asian countries. There are some studies on the pathway from SES to diet/nutrition. The association between low SES and obesity may be mediated, in part, by the low cost of energy-dense foods, concern about food price and dietary knowledge. Nutrition policy research is required to reduce nutrition disparities in Asia. We need a collaborative study of the impact of potential political options on diet and on health with other academic fields.
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Prediction of fluoroquinolone-induced elevation in serum creatinine levels: a case of drug-endogenous substance interaction involving the inhibition of renal secretion.
Imamura, Y, Murayama, N, Okudaira, N, Kurihara, A, Okazaki, O, Izumi, T, Inoue, K, Yuasa, H, Kusuhara, H, Sugiyama, Y
Clinical pharmacology and therapeutics. 2011;(1):81-8
Abstract
The aim of this study was to examine the mechanism underlying the elevation in serum creatinine levels caused by a novel des-fluoro(6)-quinolone antibacterial agent, DX-619, in healthy subjects. hOCT2 showed a prominent uptake of creatinine (K(m) = 56.4 mmol/l) among renal organic ion transporters. DX-619 is a potent inhibitor of hOCT2 (K(i) = 0.94 micromol/l), hMATE1 (0.82 µmol/l), and hMATE2-K (0.10 micromol/l). The pharmacokinetic model involving the inhibition of hOCT2 (model 1), hOCT2, and MATE1 or MATE2-K (model 2) could predict the elevation in serum creatinine levels in individual subjects receiving DX-619. This assumes that a significant contribution of tubular secretion (59, 38, and 31%) and reabsorption ranged from 3-50, 4-30, and 5-21% in model 1, -2a (hOCT2/hMATE1), and -2b (hOCT2/hMATE2-K), respectively, for creatinine. In conclusion, DX-619, at its therapeutic dose, is able to inhibit hOCT2, hMATE1, and hMATE2-K, leading to a significant inhibition of tubular secretion of creatinine and consequently to elevation of serum creatinine levels.
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Effect of Rikkunshi-to on appetite loss found in elderly dementia patients: a preliminary study.
Utumi, Y, Iseki, E, Murayama, N, Nozawa, M, Kumagai, R, Matsubara, Y, Ichimiya, Y, Arai, H
Psychogeriatrics : the official journal of the Japanese Psychogeriatric Society. 2011;(1):34-9
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Abstract
BACKGROUND Functional gastrointestinal symptoms are frequently found in elderly dementia patients. In such a case, we attempt treatment by the administration of antidepressants or second-generation antipsychotics. However, these medications have a risk of side-effects. In the present study, we carried out oral administration of Rikkunshi-to to elderly dementia patients with appetite loss, and examined its effects on food intake. METHODS Six elderly dementia patients were recruited from inpatients. They showed appetite loss, but no organic abnormalities of the gastrointestinal organs. These patients were given Rikkunshi-to, at 7.5 g per day, t.i.d. for 4 weeks. We examined the food intake, weight, total protein, albumin and potassium in plasma before administration and for 4 weeks after administration. In statistical analyses, the percentage of food consumed for 4 weeks was analyzed by anova. We also examined the side-effects of Rikkunshi-to. RESULTS In patient 3, we stopped investigation after 3 weeks because of the development of cholecystitis. The values of 4 weeks in patient 3 were calculated as the mean values of 4 weeks in the other five patients. anova and Tukey's multiple comparison showed a marginally significant difference in weight between before Rikkunshi-to was given and 4 weeks after. In change of food intake, there were no significant differences between before Rikkunshi-to was given and 1 day after, 1 day and 2 days after, 2 days and 3 days after, 3 days and 1 week after, and 1 week and 2 weeks after; however, there were significant increases in food intake between other times. With regard to the side-effects, mild lower limb oedema appeared in the two patients. CONCLUSION In the present study, we showed the effect of Rikkunshi-to in improving appetite loss in elderly dementia patients. The present study suggests that Rikkunshi-to might be useful in improving functional appetite loss in elderly dementia patients, because there are no serious side-effects.
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Oxidation of endobiotics mediated by xenobiotic-metabolizing forms of human cytochrome.
Niwa, T, Murayama, N, Yamazaki, H
Current drug metabolism. 2009;(7):700-12
Abstract
Cytochrome P450s (P450 or CYPs) comprise a superfamily of enzymes that catalyze the oxidation of a wide variety of xenobiotic chemicals including drugs and environmental carcinogens. Recent studies have demonstrated that endogenous chemicals are also oxidized by human P450s which mainly metabolize xenobiotics. In this review, we summarize the expected physiological significance of the biotransfornation as well as Michaelis-Menten constants (Km), maximal velocities (Vmax), Vmax/Km (intrinsic clearance) values, and/or metabolic activities for 33 endogenous substrates, including (1) arachidonic acid and fatty acids, (2) steroid hormones, such as testosterone, progesterone, and allopregnanolone, (3) amines, such as tyramine, and (4) lipid-soluble vitamins, such as retinol and vitamin D3 analogues, mediated human P450 isoforms consisting of so-called drug-metabolizing enzymes for the purpose of predicting the key enzyme(s) in vivo. Arachidonic acid is metabolized via the epoxidation and omega-hydroxylation to many biologically active eicosanoids such as epoxyeicosatrienoic acids and hydroxyeicosatetraenoic acids by multiple P450 isoforms including CYP2C, CYP2E1 and CYP4A11. CYP2D in the brain may be involved in the metabolism of neuronal amines and steroids and in the regulation of the central nervous system. CYP1A2 and CYP3A4 appear to be the major P450 enzymes catalyzing the oxidation of all-trans-retinol to all-trans-retinoic acid in human liver, and CYP3A4 is one of the vitamin D3 25-hydroxylases. Although the significance of the contribution is still unknown in detail, the collective findings provide fundamental and useful information for the biological contribution of the metabolism of endogenous substances by drug-metabolizing enzymes, P450s. In addition, genetic polymorphism of these drug-metabolizing P450s may affect the metabolism of the endobiotics. Forthermore, these findings imply that xenobiotic oxidations by P450 enzymes are affected by endobiotic molecules and that the endobiotic-xenobiotic interactions as well as drug-drug interactions or drug-food/beverage interactions may be of great importance when understanding the basis for pharmacological and toxicological actions of a number of xenobiotic chemicals.