50 years of the water-flow variance in Tucuruí reservoir related with Brazilian energy consumption.

Dammed rivers lose its natural characteristics of the flow cycle and becomes controlled by the energy demands of the hydroelectric plants. With the connection of the energy-producing plants to a central station in Brazil the situation is aggravated since demands in different regions of the country affect the water flow. Using downstream flow data from the Tucuruí dam over a 50-year period, we tested whether the variation in water flow has changed. We observed an increase of the annual variation of the water flow and the extreme events of flooding at downstream of the dam, indicating the operation of the dam intensified the control of water passage. The study reveals an increase in the variation of water flow in the dam's downstream section following the interconnection of the Tucurui dam with the Central System in 1997. Management strategies for the dam should be considered integrated with the national electricity demand, since distant demands may affect the local environment in question.

Carrier and spin dynamics of high-density exciton magnetic polarons in Cd0.8Mn0.2Te.

We investigated the carrier and spin dynamics of high-density exciton magnetic polarons (HD-EMPs) in Cd0.8Mn0.2Te based on the measurement of their time-resolved photoluminescence (PL) spectra and polarization states, and the utilization of photo-induced Faraday rotation techniques. The PL from the HD-EMPs were collected in a forward scattering configuration, and was observed as a pulsed emission of a few picoseconds duration, exhibiting a blue-shift with time evolution. The blue shift originated from the refractive-index dispersion of the sample. By excluding the influence of the refractive-index dispersion on the time profile, it was revealed that the ultra-short pulsed emission with a time width smaller than 1 ps was initially radiated with a time delay of ~2.4 ps after photoexcitation. From the results of time evolution of the polarization states, it is concluded that the exciton-Mn spin interactions occurs immediately after the excitation, which causes the Mn ion spins to align to follow the spin states of photoexcited excitons. The alignment of the Mn ion spins through the formation of the HD-EMPs was significantly faster than that of the localized EMP. On the other hand, the time evolution of the photo-induced Faraday rotation showed two decay components attributed to spin relaxations of the excitons and Mn ions within the HD-EMP. The observation of the Faraday rotation signal due to the Mn ion spins further confirms that these spins were aligned by the photo-excited spin-aligned excitons. Our findings suggest a novel mechanism for the effective optical control of spins in a semimagnetic semiconductor, which is associated with a multi-exciton system and its localized state.

Dietary intake of antioxidant vitamins and risk of stroke: the Japan Public Health Center-based Prospective Study.

BACKGROUND/OBJECTIVES: Epidemiologic evidence on the relationship between antioxidant vitamin intake and stroke is limited. We aimed to investigate the association between dietary intake of antioxidant vitamins and the incidence of total stroke and ischemic stroke. SUBJECTS/METHODS: The subjects were 82 044 Japanese men and women aged 45-74 years under the Japan Public Health Center-based Prospective Cohort Study. Between 1995 and 1997, dietary assessment was done using a food frequency questionnaire. During 983 857 person-years of follow-up until the end of 2009 we documented 3541 incident total strokes and 2138 ischemic strokes. RESULTS: Dietary intakes of α-carotene, ß-carotene, α-tocopherol and vitamin C were not inversely associated with the incidence of total stroke and ischemic stroke adjustment for cardiovascular risk factors and selected lifestyle variables. When stratified by current smoking status, the inverse association between dietary vitamin C intake and incidence of total stroke observed among non-smokers but not smokers, with respective multivariable hazard ratios for the highest versus lowest quintiles of vitamin C of 0.81 (95% confidence interval (CI), 0.68-0.96; P-trend=0.03) among non-smokers; and 1.03 (0.84-1.25; P-trend=0.55) among smokers. As for ischemic stroke, the corresponding multivariable hazard ratios were 0.76 (0.60-0.96; P-trend=0.02) among non-smokers; and 1.00 (0.78-1.28; P-trend=0.61) among smokers. CONCLUSIONS: Dietary vitamin C intake was inversely associated with the incidence of total stroke and ischemic stroke among non-smokers.

Faecal corticosterone levels of dogs relinquished to a shelter in Japan.

This study investigated the baseline level of faecal corticosterone in dogs relinquished to a shelter and compared changes in it caused by social events that dogs experienced. Faecal corticosterone was measured to assess the average stress levels of dogs that depend on the actual conditions of the shelter. One category of subject animals was dogs relinquished by their owner or stray dogs who were penned in a group (group RG) or caged individually due to their incompatibility (group RI), and the other category was demonstration dogs kept for dog training classes (group DT) and petting activities held in welfare facilities for the elderly and in elementary schools (group DP). While the number of dogs that were included in groups RG and RI fluctuated almost daily, the demonstration dogs were kept together for three months. The average level of faecal corticosterone was significantly higher in group RG than in groups DT and DP. The level of group RI was also relatively high, but the difference from the other three groups was not statistically significant. Faecal corticosterone concentrations of groups DT and DP rose somewhat from the baseline levels on the day after social service activities. The results of this study reaffirm that temporarily relinquished and socially unstable dogs especially suffer a certain level of stress in a shelter.

Seasonal differences in total antioxidant capacity intake from foods consumed by a Japanese population.

BACKGROUND/OBJECTIVES: This cross-sectional study aimed to estimate total antioxidant capacity (TAC) intake from food and beverages in a Japanese population from 7-day seasonal dietary records. SUBJECTS/METHODS: The 7-day weighed dietary records of 390 subjects over four seasons between 1996 and 1998 were used. The TAC values (µmol trolox equivalents (µmol TE)/g) of various foods and beverages were defined, as reported in previous studies for weighed dietary records, using several different methods. TAC values of foods were estimated in 242 food and beverage items: 86.5% of vegetables, 99.1% of fruits, 71.5% of potatoes, 96.7% of beans, and 100% of chocolates. Differences in TAC intake per day and intake (g) per day among seasons in each of the food and beverage group were compared using a general linear model for repeated measures. The TAC intake/day were calculated for each food and beverage item in the four seasons. RESULTS: TAC intake/day (µmol TE/day) varied from 10 189 (summer) to 12 292 (winter). TAC intake/day from fruits (2696) and potatoes (395) was highest in autumn, from vegetables (2827) it was highest in summer and from beans (4151) and tea (2331) it was highest in winter. CONCLUSIONS: The dietary habits of the studied Japanese population showed the highest antioxidant capacity in winter and the lowest in summer.

Rice, bread, noodle and cereal intake and colorectal cancer in Japanese men and women: the Japan Public Health Center-based prospective Study (JPHC Study).

BACKGROUND: Colorectal cancer (CRC) incidence rate increased rapidly in Japan between the 1950s and 1990s. We examined the association between rice intake and CRC risk in comparison with bread, noodles and cereal among Japanese adults enrolled in the Japan Public Health Center-based prospective Study. METHODS: A total of 73,501 Japanese men and women were followed-up from 1995 to 1999 until the end of 2008 for an average of 11 years. During 801,937 person-years of follow-up, we identified 1276 incident cases of CRC. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) of CRC for rice, noodle, bread and cereal intake were calculated by Cox proportional hazards model. RESULTS: Overall, no significant association was observed for the highest quartile of rice intake compared with the lowest and the risk of CRC and its subsites in men (HR, 0.77; 95% CI, 0.56-1.07) and women (HR, 1.10; 95% CI, 0.71-1.68). However, a non-significant inverse trend was observed between rice intake and rectal cancer in men. No clear patterns of association were observed in bread, noodle and cereal intake. CONCLUSION: Our findings suggest that the consumption of rice does not have a substantial impact on the risk of CRC in the Japanese population.

Dietary patterns and type 2 diabetes in Japanese men and women: the Japan Public Health Center-based Prospective Study.

BACKGROUND/OBJECTIVE: Dietary patterns in Western populations have been linked to type 2 diabetes, but the association of distinctive dietary patterns of Japanese population remains unclear. We prospectively investigated the association between dietary patterns and risk of developing type 2 diabetes among Japanese adults. SUBJECTS/METHODS: Participants were 27, 816 men and 36,889 women aged 45-74 years who participated in the second survey of the Japan Public Health Center-based prospective study and had no history of diabetes. Dietary patterns were derived by using principal component analysis of the consumption of 134 food and beverage items ascertained by a food frequency questionnaire. Odds ratios of self-reported physician-diagnosed type 2 diabetes over 5 year were estimated using logistic regression analysis. RESULTS: A total of 1194 new cases (692 men and 502 women) of type 2 diabetes were self-reported. We identified three dietary patterns: prudent, westernized and traditional Japanese patterns. Any dietary pattern was not significantly associated with type 2 diabetes risk after adjustment for covariates in both men and women. The multivariate-adjusted odds ratios (95% confidence interval) for type 2 diabetes for the highest versus lowest quartile of each dietary pattern score in men and women, respectively, were 0.93 (0.74-1.16) and 0.90 (0.69-1.16) for the prudent pattern, 1.15 (0.90-1.46) and 0.81 (0.61-1.08) for the westernized pattern, and 0.97 (0.74-1.27) and 0.87 (0.66-1.15) for the traditional pattern. CONCLUSIONS: Although a small protective effect of the prudent dietary pattern cannot be excluded, dietary patterns may not be appreciably associated with type 2 diabetes risk in Japanese.

Requirement of integrin ß3 for iron transportation during enamel formation.

Rodent incisors exhibit pigmentation on their labial surfaces. Although previous studies have shown that this pigment is composed of iron, the existence of other elements has not been investigated. This study found that the lower incisors of CD61, also known as integrin ß3, null mice (CD61(-/-)) lacked pigmentation. Although ameloblasts differentiated and formed enamel normally, no ferric ion accumulation was observed in maturation-stage ameloblasts in CD61(-/-) mice. Surface elements of control and CD61-/- lower incisors were compared by x-ray photoelectron spectroscopy (XPS). XPS analysis detected C, Ca, N, O, and P on the labial surfaces of lower incisors of both mice, whereas Fe was detected only in control samples. No peak of non-ferrous metal or other element was detected in either group. Quantitative RT-PCR analysis of 18 iron-transportation-related genes with mRNA from maturation-stage ameloblasts and ALC, a pre-ameloblastic cell line, was performed. The results suggested that CD61 regulates the expressions of Slc11a2 and Slc40a1, both of which are involved in iron transportation in epithelial tissues. These results suggested that the pigment on the labial surface of mouse incisors is composed of Fe and that both anemia and reduction of iron-transporting proteins may cause the loss of pigmentation in CD61(-/-) mice.

Dietary fiber intake and risk of cardiovascular disease in the Japanese population: the Japan Public Health Center-based study cohort.

BACKGROUND/OBJECTIVES: There has been no study with regard to the association between dietary fibers and the incidence of stroke and coronary heart disease (CHD) in Asia. We investigated the association between dietary fiber and the risk of cardiovascular disease (CVD), which we defined as stroke or CHD, in a Japanese population. SUBJECTS/METHODS: We studied 86 387 Japanese subjects (age 45-65 years, without CVD or cancer in 1995 as Cohort I and in 1998 as Cohort II) and used a self-administered questionnaire to follow-up the participants until the end of 2004. Dietary fiber intake was estimated from food-frequency questionnaires comprising 138 food items. RESULTS: After 899 141 person-years of follow-up, we documented the incidence of 2553 strokes and 684 cases of CHD. Multivariable-adjusted hazard ratios (95% confidence intervals (CIs)) of CVD for the third to fifth quintiles of total fiber were 0.79 (0.63-0.99), 0.70 (0.54-0.89) and 0.65 (0.48-0.87) in women, respectively, compared with the lowest quintile. Total fiber intake was inversely associated with the incidence of stroke, either cerebral infarction or intracerebral hemorrhage in women. The results for insoluble fiber in women were similar to those for total fiber, whereas those for soluble fiber were weak. An inverse association of total fiber with CVD was observed primarily in non-smokers (P for trend=0.045 and 0.001) and not in smokers (probability values for interaction between total fiber and smoking were 0.06 and 0.01 in men and women, respectively). CONCLUSIONS: Higher total dietary fiber was associated with reduced risk of CVD in Japanese non-smokers.

Effect of cooking loss in the assessment of vitamin intake for epidemiological data in Japan.

BACKGROUND/OBJECTIVES: The effect of cooking loss on vitamin intake is an important consideration in dietary and epidemiological studies in Japanese. However, because few published food values have considered cooking effect, allowing for cooking loss in the assessment of vitamin intake in Japan has been difficult. SUBJECTS/METHODS: Seven-day dietary records and a fasting blood sample were collected from 102 men and 113 women in August of 1994 or 1995. Vitamin intake were estimated using two food databases, one composed of raw food only and the second of cooked food. Estimates were compared with blood levels. RESULTS: Water-soluble vitamin intake using a food database including cooked food was lower than intakes estimated using a database composed of raw food only, except for pantothenic acid and vitamin B(12) intake. In particular, vitamin B(1) intake was 18.9% lower in men and 16.8% lower in women. However, when subjects were classified into the same and adjacent categories by joint classification by quintiles, appreciable change in ranking of a subject was not observed. Furthermore, the relationship between vitamin intake and biomarker did not improve when intake was calculated using a food database including cooked food. CONCLUSION: Although the effect of cooking loss on absolute values is not negligible, this might not significantly impact the ranking of subject intake estimations of vitamin intake in epidemiological studies.

Analysis of estrogenic activity of foodstuffs and cigarette smoke condensates using a yeast estrogen screening method.

Hormone mimics present in our environment are of concern because such agents could potentially reduce fertility and increase sexual dysfunction in wildlife and increase the risk of breast and reproductive organ cancers in man. Therefore, monitoring of the levels of estrogenic compounds in environmental materials is essential in order to prevent their exposure to man and to discover potential harmful effects on human health. In the present study, we analyzed estrogenic activity in 23 foodstuffs and cigarette smoke condensate samples extracted with an organic solvent, using the yeast estrogen screening (YES) system. Three soybean-related foodstuffs (soy sauce, tofu, miso), beer, coffee and cigarette smoke condensates showed clear estrogenic activity in the YES system. HPLC fractionations followed by the YES of these YES-positive samples revealed the presence of many estrogenic compounds in cigarette smoke condensates, whereas the other samples exerted estrogenic activities in only one or two fractions. Genistein was able to be isolated as the major active principle in soy sauce, tofu and miso, its concentration in these three foodstuffs ranging from 0.1 to 394 microg/g or ml. 8-Prenylnaringenin was also isolated from beer extracts as a major compound with estrogenic activity present at 0.22-4.0 ng/ml. Estrogenic activity of 8-prenylnaringenin with YES was 10-times as high as that of genistein, although it was 100-times less than that of 17beta-estradiol. Based on our results in vitro, 10 mg miso and 10 ml beer can be calculated to have similar estrogenic activity to 1 pmole 17beta-estradiol. It is very important that the effects of genistein and 8-prenylnaringenin on human health are elucidated.

On the bioactive conformation of the rhodopsin chromophore: absolute sense of twist around the 6-s-cis bond.

Incubation of opsin with synthetic 6-s-locked retinoids 2a and 2b only led to pigment formation from the alpha-locked 2a, the CD spectrum of which was similar to that of native rhodopsin (Rh). This establishes that the 6-s-bond of the chromophore in rhodopsin is cis, and that its helicity is negative. Earlier cross-linking studies showed that the 11-cis to all-trans photoisomerization occurring in the batho-Rh to lumi-Rh conversion induces a flip over of the side carrying the ring moiety. The GTP-binding assay of pigment Rh-(2a), incorporating retinal analogue 2a, has shown that its activity is 80% that of the native pigment. That is, the overall conformation around the 6-s bond is retained in the steps leading to G-protein activation.

Testicular toxicity in F344 rats by aminophenylnorharman, formed from norharman and aniline.

9-(4'-Aminophenyl)-9H-pyrido[3,4-b]indole [aminophenylnorharman (APNH)] is a novel mutagenic heterocyclic amine, produced by the reaction of norharman with aniline in the presence of S9 mix. In the present study, the acute toxicity of this compound was investigated in male F344 rats. Ten-week-old animals were treated with a single intragastric injection of APNH at doses of 45 or 90 mg/kg body wt and euthanized 1, 3, or 6 days afterward. When APNH was administered at a dose of 90 mg/kg, vacuolation of Sertoli cells in the testis was seen at 1 day after treatment. The testicular damage had markedly progressed by day 6, with multinucleated giant cells and loss of round spermatids in the seminiferous tubules observed in groups 1 and 2 of the four histological categories of spermatogenesis. Numbers of spermatogonia were also decreased by APNH treatment. No toxic changes were observed in Leydig cells under these conditions and serum follicle-stimulating hormone and luteinizing hormone concentrations were also unchanged from control values. Such severe testicular damage was not observed at any time point at the 45 mg/kg dose level of APNH. Moreover, neither norharman nor aniline alone exerted acute testicular toxicity at doses equivalent to 90 mg/kg of APNH. In addition to the testicular lesions, erosive changes of urinary bladder, thymic atrophy, and panmyelophthisis were evident in rats given APNH at 90 mg/kg.

Validity and reproducibility of a self-administered questionnaire to determine dietary supplement users among Japanese.

OBJECTIVE: To evaluate reproducibility and validity of a self-administered food frequency questionnaire (FFQ) to determine the dietary supplement use. DESIGN: Questionnaire data were compared with dietary records (DR) in four 7 day periods for validity. FFQ1 and FFQ2 administered at an interval of approximately one year were compared for reproducibility. SETTING AND SUBJECTS: A total of 361 samples were selected for a validation study of a questionnaire from the subgroup of the Japan Public Health Center-based prospective Study on cancer and cardiovascular disease (JPHC Study) cohort II. Categories of dietary supplements in the FFQ were 'multivitamins', 'beta-carotene', 'vitamin C', 'vitamin E', and 'other supplements'. For each category, inquiries were made as to the brand name, frequency and duration of use. A dietary supplement user was defined as a subject who used a dietary supplement one or more times a week for a year or longer. RESULTS: Prevalence of overall supplement use was 10.9%. Percentage agreement between FFQ1 and FFQ2 was 91.7%. Sensitivity and specificity of supplement use by FFQ were 80.6% and 89.2%, respectively. Sensitivity was high for 'vitamin C'. When the self-reported categories were corrected, sensitivity for 'multivitamins' and 'vitamin E' improved. CONCLUSIONS: The FFQ on dietary supplements used for the JPHC 5 y follow-up survey was valid to determine overall use and well-defined dietary supplement use such as vitamin C. Categories must be corrected when determining multivitamin and 'vitamin E'.

Induction of liver preneoplastic lesions by aminophenylnorharman, formed from norharman and aniline, in male F344 rats.

9-(4'-Aminophenyl)-9H-pyrido[3,4-b]indole (aminophenylnorharman, APNH), produced by the reaction of norharman with aniline in the presence of S9 mix, is a novel heterocyclic amine (HCA), with mutagenicity to Salmonella typhimurium TA 98 and YG 1024 comparable to that of other HCAs such as 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx). This experiment was designed to investigate its potential to induce glutathione S-transferase placental form (GST-P) positive foci in the liver. Male F344 rats, 7 weeks old, were fed diet containing 0, 10, 20, or 50 ppm APNH for 4 weeks, killed by ether euthanasia and performed complete necropsy. Numbers of GST-P positive foci larger than 0.1 mm in diameter induced by APNH at the dose of 10, 20, and 50 ppm were increased in a dose dependent manner to 0.52, 1.3, and 21 foci/cm2, respectively, with areas of 0.006, 0.01, and 2.3 mm2/cm2. No such GST-P positive foci were observed in rats fed control diet. These findings suggest that APNH has hepatocarcinogenic potential in male F344 rats.

Frequent association of 22q11.2 deletion with tetralogy of Fallot.

Chromosome 22q11.2 deletion causes DiGeorge syndrome, velocardiofacial syndrome, conotruncal anomaly face syndrome with tetralogy of Fallot (TOF), and sporadic or familial TOF. To determine the prevalence and clinical importance of the 22q11.2 deletion in TOF, a series of 212 Japanese TOF patients was studied. The type of pulmonary blood supply, which may lead to various clinical outcomes, and other additional anomalies were evaluated clinically. The 22q11.2 deletion was diagnosed by fluorescence in situ hybridization with N25 and TUPLE1 probes. Of the 212 patients examined, 28 (13%) had a 22q11.2 deletion, the frequency being higher than that in TOF patients with trisomy 21. The prevalence of the deletion in TOF patients with pulmonary atresia (PA) plus major aortico-pulmonary collateral arteries (MAPCA) was significantly higher than the value in patients with PA plus patent ductus arteriosus (PDA) (P = 0.04) or with pulmonary stenosis (PS) (P < 0.0001). All 28 patients with 22q11.2 deletion had one or more extracardiac abnormalities. Four of 9 patients with the 22q11.2 deletion and TOF-PA-MAPCA suffered from bronchomalacia, while none of 19 patients with TOF-PA-PDA or TOF-PS manifested bronchomalacia (P = 0.006). These results indicate that 22q11.2 deletion is the most frequent cause of syndromic TOF, especially for TOF-PA-MAPCA, and bronchomalacia is the clinically most important associated anomaly in TOF-PA-MAPCA patients.

Evaluation of gamma thalamotomy for parkinsonian and other tremors: survival of neurons adjacent to the thalamic lesion after gamma thalamotomy.

OBJECT: The effects of gamma thalamotomy for parkinsonian and other kinds of tremor were evaluated. METHODS: Thirty-six thalamotomies were performed in 31 patients by using a 4-mm collimator. The maximum dose was 150 Gy in the initial six cases, which was reduced to 130 Gy thereafter. The longest follow-up period was 6 years. The target was determined on T2-weighted and proton magnetic resonance (MR) images. The point chosen was in the lateral-most part of the thalamic ventralis intermedius nucleus. This is in keeping with open thalamotomy as practiced at the authors' institution. In 15 cases, gamma thalamotomy was the first surgical procedure. In other cases, previous therapeutic or vascular lesions were visible to facilitate targeting. Two types of tissue reaction were onserved on MR imaging: a simple oval shape and a complex irregular shape. Neither of these changes affected the clinical course. In the majority of cases, the tremor subsided after a latent interval of approximately 1 year after irradiation. The earliest response was demonstrated at 3 months. In five cases the tremor remained. In four of these cases, a second radiation session was administered. One of these four patients as well as another patient with an unsatisfactory result underwent open thalamotomy with microrecording. In both cases, depth recording adjacent to the necrotic area revealed normal neuronal activity, including the rhythmic discharge of tremor. Minor coagulation was performed and resulted in immediate and complete arrest of the remaining tremor. CONCLUSIONS: Gamma thalamotomy for Parkinson's disease seems to be an alternative useful method in selected cases.

Quantification of the co-mutagenic beta-carbolines, norharman and harman, in cigarette smoke condensates and cooked foods.

Co-mutagenic beta-carbolines, such as norharman and harman, were quantified in mainstream and sidestream smoke condensates of six Japanese brands of cigarettes, and also in 13 kinds of cooked foods, using a combination of blue cotton treatment and HPLC. Norharman and harman were detected in all the cigarette smoke condensate samples. Their levels in the mainstream smoke case were 900-4240 ng per cigarette for norharman, and 360-2240 ng for harman, and in sidestream smoke, 4130-8990 ng for norharman and 2100-3000 ng for harman. These beta-carbolines were also found to be present in all the cooked food samples, at levels of 2.39-795 ng for norharman and 0.62-377 ng for harman per gram of cooked food. The observed concentrations are much higher than those found for mutagenic and carcinogenic heterocyclic amines (HCAs), suggesting that humans are exposed to norharman and harman in daily life to a larger extent than to HCAs.