Single Ingestion of Trehalose Enhances Prolonged Exercise Performance by Effective Use of Glucose and Lipid in Healthy Men.

Trehalose increases blood glucose levels slowly and induces a slight insulin response. The present study aimed to study the effect of trehalose on prolonged exercise performance. The participants were 12 healthy men (age: 21.3 ± 0.9 y). After an overnight fast (12 h), they first exercised with a constant load (intensity: 40% V˙O2peak) for 60 min using a bicycle ergometer. They continued to exercise with a constant load (40% V˙O2peak) for 30 min between four sets of the 30-s Wingate test. After the 1st set, each participant ingested 500 mL water (control), 8% glucose, or 8% trehalose in three trials. These three trials were at least one week apart and were conducted in a double-blind and randomized crossover manner. Blood was collected for seven biochemical parameters at 12 time points during the experiment. The area under the curve of adrenaline after ingestion of trehalose was significantly lower than that for water and tended to be lower than that for glucose in the later stage of the exercise. Lower secretion of adrenaline after a single dose of 8% trehalose during prolonged exercise reflected the preservation of carbohydrates in the body in the later stage of the exercise. In conclusion, a single ingestion of trehalose helped to maintain prolonged exercise performance.

Effects of a Single Ingestion of Trehalose during Prolonged Exercise.

Trehalose (TRE), a disaccharide, is absorbed slowly and gradually increases the blood glucose (GLU) level along with reducing insulin secretion. The aim of this study was twofold. First, we examined exercise performance following ingestions of either GLU, TRE, or water (WAT). The second purpose was to investigate the effects of TRE energy metabolism during prolonged exercise. We examined exercise performance using the Wingate test, with 30-min constant load exercise at 40% VO2peak after exercising for 60 min at 40% VO2peak, by using an electromagnetic brake-type bicycle ergometer (Part 1). The power values, blood glucose and lactate, and respiratory exchange ratio (RER) were measured. In addition, we investigated the energy metabolism after a single ingestion of TRE, by measuring the RER and estimating the lipid oxidation for 60 min at 40% VO2peak (Part 2). Healthy college male students performed three trials-(1) placebo (WAT), (2) GLU, and (3) TRE. Repeated two-way analysis of variance (ANOVA) was used for a comparison of the data among the three trial groups. A multiple comparison test was performed using post hoc Bonferroni correction. The TRE ingestion significantly increased the average and maximum power values (p < 0.01). The TRE ingestion showed significantly higher lipid utilization than the GLU lipid oxidation values the in TRE, 12.5 ± 6.1 g/h; GLU, 9.3 ± 4.7 g/h; and WAT, 15.0 ± 4.4 g/h; (p < 0.01). In conclusion, we provide novel data that a single TRE ingestion was effective in improving prolonged exercise performance by effective use of glucose and lipids.

Pilot Study on Interferon-γ-producing T Cell Subsets after the Protective Vaccination with Radiation-attenuated Cercaria of Schistosoma japonicum in the Miniature Pig Model.

CLAWN miniature pig has been shown to serve as a suitable host for the experimental infection of Schistosoma japonicum. In this study, we found that radiation-attenuated cercaria (RAC) vaccine gave CLAWN miniature pigs protective immunity against subsequent challenge infection with S. japonicum cercaria. To characterize the protective immune response of the pig model vaccinated by attenuated cercaria, flow cytometric analysis of the reactive T cell subsets was performed. The intracellular interferon (IFN)-γ and the cell surface markers revealed the peripheral blood CD3+ T-lymphocytes produced significant amounts of IFN-γ during the immunization period and after the challenge infection. CD4+ αß-T cells as well as CD4+/CD8α(mid) double positive and/or CD8α(high) αß-T cells were the major IFN-γ-producing CD3+ T cells. On the contrary, γδ T cells did not produce intracellular IFN-γ. Our results suggested that RAC-vaccinated miniature pigs showed effective protective immunity through the activation of αß T cells bearing antigen specific T-cell receptors but not through the activation of γδ T cells.

Sequential measurements of glomerular filtration rate in conscious rats by a bolus injection of iodixanol and a single blood sample.

To estimate the glomerular filtration rate (GFR) sequentially in conscious rats, we validated a single-blood-sample method using a bolus injection of the nonionic contrast medium iodixanol as a tracer. First, to clarify basal age-related GFR profiles, iodixanol was intravenously administered once weekly at 1500 mg kg(-1) I to clinically healthy male F344 rats from 6 to 15 weeks of age. The blood sample was collected 120 min later, and serum iodixanol concentration was measured by HPLC. GFR values decreased gradually by 9 weeks, presumably due to rapidly increased body weights, and then remained constant from 10 weeks onward. When converting the GFR from body weight to body surface area, the reference range (40-60 ml min(-1) m(-2) ) in the latter was much more stable than that (6-11 ml min(-1) kg(-1) ) in the former. For nephropathy rats induced by cisplatin (3.75-7.5 mg kg(-1) , i.v., single dose), bromoethylamine hydrobromide (BEA, 250-500 mg kg(-1) , i.v., single dose) or puromycin aminonucleoside (PAN, 15 mg kg(-1) day(-1) , s.c., 10 days), GFR decreased or tended to decrease before increasing in serum urea nitrogen (UN) and creatinine concentrations. Accordingly, serum UN and creatinine concentrations became elevated when the GFR decreased to 50-60% of the basal value. This method without urine collection contributes to the reduction of animal numbers because of repeated application to the same animals.

Assessment of voiding function in inhabitants infected with Schistosoma haematobium.

Voiding function of Schistosoma haematobium infected students was evaluated in 45 schoolboys in Kwale district, Coast province, Kenya, using a questionnaire and uroflowmetry. Sixty-eight schoolboys who were S. haematobium negative were also examined. Symptoms related to the lower urinary tract were qualitatively assessed using the International Prostate Symptoms Score (I-PSS) questionnaire. The I-PSS showed that S. haematobium infected boys felt the need to strain to urinate and post voiding some urine still remained. To examine the disturbances revealed by I-PSS quantitatively, voiding was assessed by a portable uroflowmeter and a bladder scanner. Unexpectedly, no significant residual urine post voiding and no decline in urine flow rates were found in S. haematobium infected boys. However, volume-corrected maximum and average flow rates in S. haematobium infected boys were higher than in those not infected. These results suggest that cystitis associated with S. haematobium infection causes irritation and hypercontraction of the bladder.

Proteome approach for identification of schistosomiasis japonica vaccine candidate antigen.

Experimental vaccination with radiation-attenuated cercariae (RAC) confers possible practical levels of resistance to challenge infection by humoral and by cellular mechanism. Here, we aimed to identify possible vaccine antigens by using specific IgG antibody from RAC vaccinated miniature pig. Two milligrams of soluble egg antigen (SEA) or schistosomal worm antigen preparation (SWAP) was fractionated using two dimensional liquid chromatography (proteome PF 2D) consisted of high performance chromatofocusing (HPCF) and high resolution reversed phase chromatography (HPRP). Of the 42 HPCF fractions of SEA or SWAP, 26 (61.9%) or 15 (35.7%) showed positive dot blot reaction with RAC vaccinated serum respectively. The dot blot positive fractions were applied to the second HPRP column. One hundred and seven out of 26 x 96 of SEA fractions and 18 out of 15 x 96 SWAP fractions reacted with RAC vaccinated serum. From the positive fractions we chose 17 of SEA and 10 of SWAP that had no reactivity with normal cercariae infected (NCI) sera and had single peak of 214 nm; and automated N-terminal amino acid sequence based on in situ Edman Reaction was conducted. Four sequences were obtained and applied to the homology search in NCBI database. A total of eight candidate genes were listed up and their cDNA clones from schistosomula stage were obtained. Two of the recombinant proteins (AAW27472.1 and AXX25883.1) showed strong reactivity with the RAC vaccinated serum but marginal with NCI serum. This protocol using proteome PF 2D could be applicable in identifying immunoreactive proteins from crude extract for the development of vaccines or for diagnostics.

Randomized controlled trial of two forms of self-management group education in Japanese people with impaired glucose tolerance.

The aim of this study was to determine the effectiveness of education on diabetes prevention in subjects with impaired glucose tolerance. A total of 100 subjects of impaired glucose tolerance with hemoglobin A1c (HbA1c) levels >/=5.5 to <6.1% were assigned randomly to either support or control groups. All subjects received education in 8 sessions over a 6-month period. The support group consisted of 10 members collaborating with a dietitian or a nurse who learned coping skills by employing a participant-centered approach. Participants in the support group were required to keep a diary that monitored weight, food intake and blood glucose levels, while the control group attended several lectures. Subjects assigned to the support group had a reduction in mean HbA1c levels from 5.77 +/- 0.36% at baseline to 5.39 +/- 0.24% at the endpoint (p<0.01). Weight, total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and triglyceride (TG) levels also decreased (p<0.01) in the support group, whereas subjects in the control group had no observable reduction in these indices. After intervention, participants of the support group had improvements in their 2-h post-meal blood glucose levels. Support group education can be effective for improving glycemic control in participants when carried out in collaboration with educators and other team members.

Intervention with delivery of diabetic meals improves glycemic control in patients with type 2 diabetes mellitus.

The aim of this study was to investigate the effects of a diabetic meal delivery system on glycemic control over a 12 month period in patients with type 2 diabetes. A total of 77 patients with type 2 diabetes were assigned randomly into three dietary intervention groups: group M, diabetic meal delivery; group D, individual dietary counseling; and group C, conventional dietary education. In group M, HbA(1c) levels decreased significantly from 8.2 +/- 1.2% to 7.4 +/- 0.8% after 12 months (p<0.05), while in group D, HbA(1c) levels decreased significantly throughout the entire 12 month period, from 8.5 +/- 1.7% at baseline to 7.4 +/- 1.1% at the endpoint. Similarly, fasting blood glucose (FBG) levels decreased significantly between 1 and 12 months in group M (p<0.05), and decreased significantly during the entire 12 month period in group D (p<0.01). There were no significant changes in either HbA(1c) or FBG levels in group C. This study provides evidence that intervention with delivery of diabetic meals to patients with type 2 diabetes can be equally effective for achieving glycemic control as individual dietary counselling by a dietitian. Diabetic meal delivery can therefore be used successfully to provide diabetes education to outpatients.

T regulatory cell levels decrease in people infected with Schistosoma mansoni on effective treatment.

Schistosomiasis mansoni is usually a chronic infection that leads to long-term, systemic exposure to schistosome antigens. Experimental Schistosoma mansoni infection is associated with immunoregulatory mechanisms, including T regulatory cells (Treg) that may help control morbidity and dampen resistance to re-infection. We now show that some schistosomiasis mansoni patients have high proportions of CD3(+)/CD4(+)/CD25(high) Treg. On effective treatment with praziquantel, these high Treg percentages decrease, and fewer of the remaining Treg express CD45RO. The proportion of Treg in S. mansoni-infected patients is inversely related to their percentage of activated, putative effector T cells (CD3(+)/CD4(+)/CD25(medium)/HLA-DR(+) cells). We conclude some, but not all, schistosomiasis mansoni patients develop high percentages of circulating Treg, and effective treatment both decreases the levels of these cells and changes their phenotypes, possibly because of the removal of constant exposure to antigens from intravascular, egg-producing adult worms.

Estimation of interaural level difference based on anthropometry and its effect on sound localization.

Individualization of head-related transfer functions (HRTFs) is important for highly accurate sound localization systems such as virtual auditory displays. A method to estimate interaural level differences (ILDs) from a listener's anthropometry is presented in this paper to avoid the burden of direct measurement of HRTFs. The main result presented in this paper is that localization is improved with nonindividualized HRTF if ILD is fitted to the listener. First, the relationship between ILDs and the anthropometric parameters was analyzed using multiple regression analysis. The azimuthal variation of the ILDs in each 1/3-octave band was then estimated from the listener's anthropometric parameters. A psychoacoustical experiment was carried out to evaluate its effectiveness. The experimental results show that the adjustment of the frequency characteristics of ILDs for a listener with the proposed method is effective for localization accuracy.

Effect of exercise intensity on mild rhythmic-handgrip-exercise-induced functional sympatholysis.

This study attempts to clarify whether intensity of exercise influences functional sympatholysis during mild rhythmic handgrip exercise (RHG). We measured muscle oxygenation in both exercising and non-exercising muscle in the same arm in 11 subjects using near infrared spectroscopy (NIRS), heart rate, and blood pressure. We used the total labile signal to assess the relative muscle oxygenation by occlusion for 6 min. Subjects performed RHG (20 times/min) for 6 min at 10%, 20%, and 30% of maximal voluntary contraction (MVC) at random. We used a non-hypotensive lower body negative pressure (LBNP) of 220 mmHg for 2 min to elicit reproducible enhancement in muscle sympathetic nerve activity (MSNA) at rest and during RHG. LBNP caused decreases of 16.4% and 17.7% of the level of muscle oxygenation at rest (pre) in exercising (forearm) and non-exercising (upper arm) muscle respectively. Muscle oxygenation in non-exercising muscle with the application of LBNP during RHG did not change significantly at each intensity. In contrast, the decrease in muscle oxygenation in exercising muscle attenuated progressively as exercise intensity increased (10% MVC 8.8+/-2.8%, 20% MVC 7.1+/-2.0%, 30% MVC 4.6+/-3.0%), when LBNP was applied during RHG. The attenuation of the decrease in muscle oxygenation due to LBNP during RHG at 10%, 20%, and 30% was significantly different from that at rest (p<0.01). These findings indicate that functional sympatholysis during mild RHG might be attributed to exercise intensity.

The miniature pig: a unique experimental model for Schistosoma japonicum infection.

As part of a search for good animal models for human schistosomiasis, two miniature pigs of the CLAWN strain (C-1, C-2) were inoculated percutaneously with 200 Schistosoma japonicum cercariae of the Chinese strain, and the subsequent infection was monitored parasitologically, pathologically and serologically. Egg excretion into feces began at 5 weeks post-infection (p.i.) and became pronounced from 8 weeks to 17-20 weeks p.i. The average number of eggs in 1 g feces of each pig at the peak period between 8 and 20 weeks were 288 and 277, respectively. C-1 and C-2 were killed and perfused at 27 and 47 weeks p.i. and adult worm numbers recovered were 35 and 15, respectively. C-2 had at least four pairs of viable mature worms but no detectable fecal eggs for a month before perfusion, suggesting that any produced eggs were not excreted into the feces during this period. Egg deposits associated with inflammatory reactions were observed by histological examination of the liver, spleen, pancreas, mesenteric lymph nodes, lung, and small intestine. This suggests that reduced fecal excretion of eggs into the feces did not correlate to reduced parasite numbers in the chronic phase of schistosomiasis. This is the first report showing the miniature pig to be a potential model for human S. japonicum infection.

Schistosoma mansoni and alpha-galactosylceramide: prophylactic effect of Th1 Immune suppression in a mouse model of Graves' hyperthyroidism.

Graves' hyperthyroidism, an organ-specific autoimmune disease mediated by stimulatory thyrotropin receptor (TSHR) autoantibodies, has been considered a Th2-dominant disease. However, recent data with mouse Graves' models are conflicting. For example, we recently demonstrated that injection of BALB/c mice with adenovirus coding the TSHR induced Graves' hyperthyroidism characterized by mixed Th1 and Th2 immune responses against the TSHR, and that transient coexpression of the Th2 cytokine IL-4 by adenovirus skewed Ag-specific immune response toward Th2 and suppressed disease induction. To gain further insight into the relationship between immune polarization and Graves' disease, we evaluated the effect of Th2 immune polarization by helminth Schistosoma mansoni infection and alpha-galactosylceramide (alpha-GalCer), both known to bias the systemic immune response to Th2, on Graves' disease. S. mansoni infection first induced mixed Th1 and Th2 immune responses to soluble worm Ags, followed by a Th2 response to soluble egg Ags. Prior infection with S. mansoni suppressed the Th1-type anti-TSHR immune response, as demonstrated by impaired Ag-specific IFN-gamma secretion of splenocytes and decreased titers of IgG2a subclass anti-TSHR Abs, and also prevented disease development. Similarly, alpha-GalCer suppressed Ag-specific splenocyte secretion of IFN-gamma and prevented disease induction. However, once the anti-TSHR immune response was fully induced, S. mansoni or alpha-GalCer was ineffective in curing disease. These data support the Th1 theory in Graves' disease and indicate that suppression of the Th1-type immune response at the time of Ag priming may be crucial for inhibiting the pathogenic anti-TSHR immune response.

The involvement of cyclic adenosine monophosphate in the control of schistosome miracidium cilia.

This study examined the possible involvement of cyclic adenosine monophosphate (cAMP) in the control of ciliary action of Schistosoma mansoni miracidia. Miracidia immobilized in hypertonic NaCl solution were treated with 3 compounds that are known to increase intracellular cAMP concentrations. Forskolin, at a concentration of 50 microM, induced 50.1% of the miracidia to swim in hypertonic solution. The corresponding values obtained for 3-isobutyl-1-methylxanthine (IBMX) at 1 mM and 8-bromo-cAMP at 10 mM were 42.2 and 50.4%, respectively. The motility-enhancing effect of these compounds was dose dependent. Nevertheless, the swimming speed of miracidia activated in this way was only 10% of that observed in artificial pond water (APW). Cholera toxin had no apparent effect on miracidia swimming in hypertonic NaCl solution. Likewise, swimming in APW treated with forskolin at 50 microM, IBMX at 1 mM, or 8-bromo-cAMP at 10 mM did not induce any apparent change in motility. Miracidia swimming in APW were then treated with 3 compounds that decrease the intracellular concentration of cAMP. MDL-12,330A, at a concentration of 250 microM, caused a dramatic decrease in swimming over a period of 1 hr. Likewise, SQ22536 and imidazole, at concentrations of 20 and 50 mM, respectively, caused 36.5 and 73.4% decreases in swimming under the same conditions. Finally, inhibitors of cAMP-dependent protein kinase, i.e., PKI(14-22)amide, H89, and H88, completely inhibited miracidia swimming in APW at concentrations of 25, 50, and 100 microM, respectively. These results suggest that cAMP and cAMP-dependent protein kinase are involved in osmosis-controlled ciliary motion of schistosome miracidia.

Bancroftian filariasis in Nepal: a survey for circulating antigenemia of Wuchereria bancrofti and urinary IgG4 antibody in two rural areas of Nepal.

Serum and urine samples were randomly collected from residents in two rural areas at different altitudes in Nepal, and were examined for Wuchereria bancrofti antigens and antibodies (IgG4) to filarial antigens, respectively. In Judigaun, located at 900 m in altitude, 25.2% of 238 serum samples were positive for antigen, and 50.8% of 244 urine samples were positive for antibody. The level of IgG4 antibodies was higher among antigen positive individuals than among the antigen negatives. In Kotyang, located at 1100-1300 m, the prevalence of antigenemia was 15.4% of 117 serum samples.

Schemata and attitudes toward persons with intellectual disability in Japan.

375 parents of pupils were asked to respond to 14 questions on attitudes toward persons with intellectual disability. About 30% of variance in attitude was explained by a set of variables. The effects of schemata concerning person with intellectual disability had a great effect on attitudes toward such persons. The guess of a greater contribution of heredity as the basis of intellectual disability and of fewer such persons in the future of their own families than in the general population was associated with greater negative attitudes toward persons with intellectual disability. As these estimations relate to teachable information, the attitudes might be improved.

Body composition prediction equations based on bioelectrical impedance and anthropometric variables for Japanese obese women.

The tetrapolar bioelectrical impedance (BI) technique has been proposed as a convenient, valid approach to estimate body composition in normal, healthy adults. However, the validity of the BI technique for obese individuals is undetermined. The purpose of this study was to determine the validity of body composition estimated from the BI method when compared to underwater weighing with correction for residual volume, and to develop a convenient, useful equation that would sufficiently predict body composition of Japanese obese women. The order of assessing body composition was randomized for each subject. The subjects were 75 moderately or mildly obese women with a body fat content of 25.1-60.1%, aged 18-68 years. Among 12 independent variables which were arbitrarily selected as possible predictors of hydrodensitometrically determined body density (Db), BM Z/S2 was the best predictor (r = 0.803, n = 53), where BM = body mass (kg), Z = impedance (ohms), and S = stature (cm). When chronological age was added in a multiple regression analysis, Db was derived with higher accuracy (r = 0.878) with an SEE of 0.0064 g/cm3 . The linear multiple regression equation constructed for predicting the Db was, for instance, Db = 1.1171 - 0.0535BM Z/S2 - 0.0003 Age - 0.0005T, where T = triceps skinfold thickness (mm). Three equations developed in the present study were then cross-validated in a different sample (n = 22) of obese women. The results indicated that the above equation had the lowest SEE (0.0070 g/cm3 ). We suggest that body composition of Japanese obese women can be predicted with relatively high accuracy by a combination of BM Z/S2 with age and the triceps skinfold thickness. © 1992 Wiley-Liss, Inc.