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Dietary nitrate is reduced to nitrite and nitric oxide by microbial flora, and this activity is beneficial to vascular health. It has been reported that this bacterial process is inhibited by chlorhexidine mouthwash, although the effects of other products are largely unknown. This study examined the effects of several treatments on salivary nitrate/nitrite and nitrate-reducing bacteria. Twelve university staff and students performed mouth-washing with water (control), essential oil, 0.35% povidone-iodine, or 0.0025% chlorhexidine and then ate 100 g lettuce (110 mg nitrate content), followed by collection of saliva and tongue bacteria at the baseline, and 1, 5, and 10 h thereafter. The individual treatments were separated by an interval of one week. Salivary nitrate/nitrite was measured by the calorimetric method, and a representative nitrate-reducing bacterial species, Veillonella dispar, was detected and semi-quantified using a polymerase chain reaction (PCR) assay. Significant increases in salivary nitrate/nitrite were observed for all treatments (all P < 0.05). The PCR assay showed that water, essential oil, and povidone-iodine mouthwash had little effect, whereas V. dispar DNA bands were markedly inhibited after washing with chlorhexidine. These results suggest that essential oil and povidone-iodine mouthwash have little effect on oral nitrate-reducing activity. Salivary nitrite production was not reduced by chlorhexidine, but the fainter band of V. dispar DNA suggests that longer daily use might blunt this nitrate-reducing activity.

Dietary nitrate has several beneficial effects, including blood pressure reduction and improved oxygen consumption efficiency, but in order to do so it must first be reduced to nitrite by oral bacteria. Veillonella spp., a strictly anaerobic group, are the most prevalent nitrate-reducing bacteria in the oral cavity. In response to some early studies that have hinted at inter- and intra-individual variation in salivary nitrate-nitrite conversion capacity, the purpose of the present study was to investigate the incidence of and variation in the Veillonella species V. atypica, V. dispar, and V. rogosae by direct PCR and to assess salivary nitrate-nitrite conversion capacity and its reproducibility after dietary nitrate consumption in 24 elderly individuals. V. atypica, V. dispar, and V. rogosae were detected in 10 (41.7%), 24 (100%), and 14 (58.3%) participants, respectively. The coefficients of correlation between the first and second experiments on increased nitrate/nitrite were 0.637 and 0.583, respectively, both of which were statistically significant (P0.01). In both experiments, 6 participants produced relatively low levels of nitrite (0.5 mM Δ nitrite) while 7 produced relatively high levels (1.0 mM Δ nitrite). The data suggested that V. dispar was the most prevalent species, being present even in individuals producing low levels of salivary nitrite.

The outcomes of Helicobacter pylori infection vary geographically. H pylori strains, disease presentation, and environments differ markedly in Bhutan and Dominican Republic. The aims were to compare the strains, histology, and expression of interleukin (IL) 8 and IL-10 from gastric mucosa from the 2 countries. H pylori status was assessed by the combination of rapid urease test, culture, and histology. Histology was evaluated using the updated Sydney System, and cytokines in gastric biopsies were measured using real-time polymerase chain reaction (PCR). There were 138 subjects from Bhutan and 155 from Dominican Republic. The prevalence of H pylori infection was 65% and 59%, respectively. The genotype of cagA was predominantly East Asian type in Bhutan versus Western type in Dominican Republic. Gastritis severity was significantly higher in H pylori-infected subjects from Bhutan than those from Dominican Republic. IL-8 expression by H pylori infection was 5.5-fold increased in Bhutan versus 3-fold in Dominican Republic (P.001); IL-10 expression was similar. IL-8 expression levels among H pylori-infected cases tended to be positively correlated with polymorphonuclear leucocyte and monocyte infiltration scores in both countries. IL-8 expression among those with grade 2 and 3 polymorphonuclear leucocyte and monocyte infiltration was significantly higher in Bhutan than in Dominican Republic. The difference in IL-8 expression in the 2 countries is reflected in the different disease pattern between them. Whether the dominant factor is differences in H pylori virulence, in host-H pylori-environmental interactions, genetic factors or all remains unclear. However, severity of inflammation appears to be a critical factor in disease pathogenesis. We compared IL-8 messenger RNA levels between the high gastric cancer risk country, Bhutan (mainly East Asian-type H pylori), and the lower gastric cancer risk country, Dominican Republic (mainly Western-type H pylori).

Although the incidence of gastric cancer in the Dominican Republic is not high, the disease remains a significant health problem. We first conducted a detailed analysis ofHelicobacter pyloristatus in the Dominican Republic. In total, 158 patients (103 females and 55 males; mean age 47.1±16.2 years) were recruited. The status ofH. pyloriinfection was determined based on four tests: rapid urease test, culture test, histological test and immunohistochemistry. The status ofcagAandvacAgenotypes inH. pyloriwas examined using PCR and gene sequencing. The overall prevalence ofH. pyloriinfection was 58.9 %. No relationship was found between theH. pyloriinfection rate and the age range of 17–91 years. Even in the youngest group (patients aged H. pyloriinfection rate was 62.5 %. Peptic ulcer was found in 23 patients and gastric cancer was found in one patient. TheH. pyloriinfection rate in patients with peptic ulcer was significantly higher than that in patients with gastritis (82.6 versus 54.5 %,PcagA-positive/vacAs1m1 genotype was the most prevalent (43/64, 67.2 %). Compared withH. pylori-negative patients,H. pylori-positive patients showed more severe gastritis. Furthermore, the presence ofcagAwas related to the presence of more severe gastritis. All CagA-positive strains had Western-type CagA. In conclusion, we found thatH. pyloriinfection is a risk factor for peptic ulcer in the Dominican Republic. Patients withcagA-positiveH. pyloricould be at higher risk for severe inflammation and atrophy.

In Japan, there is a higher incidence of childhood obesity in the Tohoku district than in other areas. It is known that reduced physical activity is associated with increased body weight, but little is known about the physical activity patterns of children in this area. Accordingly, this study was designed to measure the physical activity of 145 children (73 boys and 72 girls) in Hashikami Town, Aomori Prefecture. Physical activity was assessed through a questionnaire as well as through two weeks of pedometer use. Boys spent more time engaging in physical activity than girls did, reporting 9.5 (0.6-22.0) versus 7.0 (1.2-21.5) hours per week [median (range)] (p=0.002). On school days, boys took an average of 13,586+/-4,386 (mean+/-SD) steps per day, while girls took 12,248+/-4,112; on holidays, boys took 9,531+/-4,557, while girls took 9,419+/-4,524. There was no significant sex-based difference in the number of steps per day (F=1.197, p=0.276), but both boys and girls significantly reduced the number of steps they took on holidays (F=116.537, p

Obese people may succeed in reducing their weight temporarily, but most of them regain the lost weight within a few years. We, therefore, recommend moderate long-term changes in habit rather than a strict temporary program. The purpose of this study was to examine whether physical activity of 40 minutes, mainly walking, was effective in improving or preventing metabolic syndrome when combined with dieting. Participants, all of whom had a waist circumferenceor= 85 cm (men) oror= 90 cm (women), were assigned into one of two groups: the control group (10 men and 11 women, age: 64.2 +/- 3.4 [SD] years) and the intervention group (10 men and 12 women, age: 62.4 +/- 4.2 years). Participants (n = 22) enrolled in a 52-week program; their diets were assessed using a 3-day dietary record and daily steps were measured with a pedometer. No significant change was seen in their dietary records, but the mean number of daily steps increased from 5,806 to 8,000-9,000. In the intervention group, BMI, waist circumference, and systolic and diastolic blood pressures decreased significantly by week 12 (all p0.001) and remained low until week 52. In fact, no significant change was seen between weeks 12 and 52. The control group showed no significant changes in all variables. These results indicate that gentle exercise of about 40 minutes in combination with dieting is effective in preventing metabolic syndrome among a sedentary population, although its effect may be limited.

Recently, many cross-sectional studies observed that body mass index (BMI) and percentage of body fat (%BF) were inversely associated with pedometer-determined physical activities, but studies on Asian populations, including the Japanese, are sparse. Height, weight, body fat percentage (%BF, bioelectrical impedance analyzer), and waist circumference were measured on 117 women (62.8+/-4.5 years, 22.2+/-2.2 kg/m(2)) and 62 men (64.0+/-4.6 years, 23.6+/-2.5 kg/m(2)). Pearson correlations and partial correlation coefficients after controlling for age were calculated between steps/day and variables. Furthermore, participants were classified into four groups as follows:5,000, 5,000-7,499, 7,500-9,999, andor=10,000 steps/day, and analyzed using ANOVA across activity groups. In women, a significant correlation was found between steps/day and BMI (r=-0.217, p=0.018), %BF (r=-0.292, p=0.0014), and the relationship was still significant after controlling for age. The relationship between steps/day and waist circumference was not significant. In men, a significant relationship was not observed between steps/day and obesity indices. The correlations between steps/day and both BMI and %BF were significant in Japanese women, but weak compared with Caucasian and African-American women as reported previously. A possible cause is racial difference in degree of obesity and body shape. The effects of physical activity on body shape and composition may differ according to race.

Summary Background & aims Small bowel bacterial overgrowth (SBBO) may be associated with malnutrition, diarrhea, and weight loss. Recently, bone mineral density (BMD) in patients with SBBO was reported to be lower, and SBBO may be an important factor in the development of metabolic bone disease. However, the subjects in these studies were relatively young patients with intestinal diseases. There is no information on the effect of SBBO on BMD in older people. Method Seventeen relatively active and 33 disabled older people participated in this study. SBBO was determined by a breath hydrogen (H2) test after ingestion of a glucose solution. BMD of the lumbar spine and femur were measured using a dual energy X-ray absorptiometry scan (DEXA). Results One healthy control and 11 disabled subjects were SBBO-positive. The Z-scores of the lumbar spine were not statistically different between groups, and a high incidence of disorders, >70%, was seen in all groups. On the other hand, there were significant differences in the femoral BMD between the healthy controls and the SBBO-negative ( P 0.001 ) and SBBO-positive ( P 0.05 ) groups. No significant difference was seen in femoral BMD between SBBO-positive and SBBO-negative institutionalized people. Conclusion SBBO seems to have little effect on BMD in people approximately 80 years old.

The antibacterial effects of salivary nitrate/nitrite on the growth of three Desulfovibrio species were examined. The bacteria did not grow on plates with ≥ 0.2 mM nitrate or ≥ 1.0 mM nitrite. They were also incubated in filter-sterilized saliva. D. desulfuricans was reduced on the order of10(2) compared with the control solution (phosphate-buffered saline) in nine out of the 10 participants.

Pentane is a widely used index of lipid peroxidation. Although isopentane, an isomer of pentane, is a major component of ambient air in urban areas, many studies have disregarded the possibility that this compound is coeluted in the measurement of breath pentane. In the present study, a gas chromatograph equipped with a cold trap apparatus and a large-bore glass capillary column was used for determination of pentane, isopentane and isoprene in breath and ambient air. Isoprene was detected in all subjects at a concentration higher than that in the ambient air. However, the concentrations of breath pentane and isopentane were similar to, or less than, those of the ambient air. We suggest that great care is required in the measurement of breath pentane so that endogenous isoprene and ambient isopentane are not coeluted.

Nitrous oxide (N2O) is produced by denitrification, i.e. by microbial reduction of nitrate (NO3−). Our previous studies have established an analytical method for demonstrating the existence of N2O in exhaled air, and we showed that levels of N2O in exhaled air increase with age after puberty. However, the source of this change and its biological significance are still unclear. The purpose of this study was to examine whether the oral microorganisms are the main source of N2O. We measured exhaled N2O in 35 young adults (aged 19–29 years) and 34 older adults (aged 61–79 years) before and after mouth cleansing. N2O was measured using an infrared-photoacoustic analyzer equipped with an optical filter (UA0985, 2215 cm−1). Participants were classified as producers and non-producers according to the levels of exhaled N2O relative to the level in the atmosphere. N2O production differed significantly between the young adult producers and the older adult producers. Mouth cleansing resulted in an immediate reduction in exhaled N2O in both groups. We only found seven (20.0%) producers in the young, and 32 (94.1%) producers in the older after mouth washing. The differences before and after mouth cleansing were significant in both groups (P

Bioelectrical impedance analysis (BIA) is commonly used to measure the percentage of body fat (%BF), but its accuracy is controversial. In addition, the equations are specific to the group for which they were established. As far as we know, there is no study examining the accuracy of BIA in Japanese middle-aged and older people. We compared %BF assessed using BIA with that of dual-energy X-ray absorptiometry (DEXA) in 102 female and 51 male local residents aged 40 to 78 y. Simple correlation coefficients were 0.79 for females and 0.69 for males, which are statistically significant (p

Background. Superficial duodenal neoplasms (SDNs) are a challenging target in the digestive tract. Surgical resection is invasive, and it is difficult to determine the site and extent of the lesion from outside the intestine and resect it locally. Endoscopic submucosal dissection (ESD) has scarcely been utilized in the treatment of duodenal tumors because of technical difficulties and possible delayed perforation due to the action of digestive juices. Thus, no standard treatments for SDNs have been established. To challenge this issue, we elaborated endoscopy-assisted laparoscopic full-thickness resection (EALFTR) and analyzed its feasibility and safety.Methods. Twenty-four SDNs in 22 consecutive patients treated by EALFTR between January 2011 and July 2012 were analyzed retrospectively.Results. All lesions were removed en bloc. The lateral and vertical margins of the specimens were negative for tumor cells in all cases. The mean sizes of the resected specimens and lesions were 28.9 mm (SD ± 10.5) and 13.3 mm (SD ± 11.6), respectively. The mean operation time and intraoperative estimated blood loss were 133 min (SD ± 45.2) and 16 ml (SD ± 21.1), respectively. Anastomotic leakage occurred in three patients (13.6%) postoperatively, but all were minor leakage and recovered conservatively. Anastomotic stenosis or bleeding did not occur.Conclusions. EALFTR can be a safe and minimally invasive treatment option for SDNs. However, the number of cases in this study was small, and further accumulations of cases and investigation are necessary.

Small bowel bacterial overgrowth (SBBO) is defined as an abnormal increase in the number of bacteria in the small intestine, and may be occult in older adults. The aim of this study was to determine whether small bowel bacterial overgrowth (SBBO) is found in healthy older people as a concomitant of normal aging or is seen only in disabled or frail older people, excluding patients with intestinal disease and those who had undergone upper intestinal or gastric surgery.Forty-one relatively healthy older people, aged 74.6 +/- 1.7 (mean +/- SE) years, who engage in regular exercise, and 42 variously disabled older people, average age 78.8 +/- 1.1 years, who commute to a day-care center participated in this study. SBBO was determined by a breath hydrogen (H2) test after ingestion of 50g of glucose solution dissolved in 200mL of water. Physical activity was judged from the number of steps walked per day as measured by a pedometer. Food intake was assessed by an interview.No SBBO-positive subject was seen among the healthy, while 11 (25.6%) of the disabled older adults were positive. The number of steps/day taken by the disabled subjects was extremely low, only 22.3% of that of the healthy (P0.001). No significant difference was seen between the groups in food intake. The mean age of the SBBO-positive patients was relatively high, 81.5 +/- 2.2 years, and 5 (45.4%) of them were underweight, with a BMI18.5.Our results and previous studies indicate that SBBO is seen only in patients with intestinal disease and disabled or frail older people.

Background : Toxic nitrite and N -nitroso compounds due to gastric bacterial growth are often detected in the stomach of patients with atrophic gastritis and partial gastrectomy. The aim of this study is to investigate whether breath N 2 O, a major metabolite of denitrification, detected after ingestion of nitrate is associated with atrophic gastritis and partial gastrectomy. Methods : Nine young, 16 normal older, nine atrophic gastritis and six partial gastrectomy subjects ingested 100 g lettuce, equal to 130 mg nitrate, and breath N 2 O was measured at 15-min intervals for 5 h. N 2 O was analyzed using an infrared-photoacoustic analyzer, and atrophic gastritis was diagnosed by pepsinogen test. Results : The mean breath N 2 O concentrations were higher in the following order at all times: partial gastrectomy>atrophic gastritis>normal>young. The maximum N 2 O concentrations in the patients with partial gastrectomy and atrophic gastritis were 1655±296 and 1350±200 (mean±S.E.) ppb, respectively, which were higher than that of the normal subjects, 827±91 ppb ( P 2 O concentration in young people was 527±86 ppb, which was lower than that of the normal older people ( P Conclusion : These higher N 2 O concentrations in gastric patients reflect bacterial growth in the stomach due to the reduction of gastric acid.

We compared two lactase preparations derived from Aspergillus orizae (AOL) and Penicillinase multicolor (PML) for stability in the stomach and overall enzymatic activity in 10 asymptomatic subjects with lactase deficiency. The subjects were given 10,000 FCC units of either AOL or PML 30 min prior to or simultaneously with 300 ml of milk. Gastric juice was withdrawn through a nasogastric tube immediately after and every 15 min for 60 min, and breath was sampled before and every 15 min for 6 h after the milk ingestion. When lactase was given simultaneously with the milk, gastric juice lactase activity and galactose concentration were significantly higher than the control levels. When lactase preparations were given 30 min prior to the milk, neither lactase activity nor galactose was detected in the gastric juice. The pH of the gastric juice was about 6.0 after the milk ingestion. Breath hydrogen did not increase when milk was ingested simultaneously with enzymes, but did increase if enzymes were given 30 min prior to milk ingestion. There were no significant differences in lactase activity, galactose concentration in gastric juice, or breath hydrogen when AOL and PML were compared. In conclusion, with exogenous lactase, digestion of lactose begins in the stomach when pH is raised to 6.0 by the buffering action of milk. Lactase preparations are effective assessed by breath hydrogen analysis in asymptomatic individuals with lactase deficiency if the enzymes are given simultaneously with milk.

The toxicity of dietary nitrate (NO3-) is controversial. One reason is nitrate metabolism in the intestine is so complicated that it is far from fully understood. There is no study measuring breath nitric oxide (NO) and nitrous oxide (N2O) after ingesting vegetables and high-nitrate food at the same time.Breath samples from 10 healthy young and 10 healthy old subjects were collected at 15-min intervals for 5 h after ingestion of 100 g of lettuce and during fasting (control). Breath NO and N2O were analyzed by a chemiluminescence and an IR-PAS analyzer respectively.N2O maximum concentration and excretions increased significantly after ingesting lettuce in each group [303 (30) vs. 750 (81) ppb, 771 (72) vs. 1668 (146) microg in young; 442 (52) vs. 1092 (109) ppb, 1088 (125) vs. 2100 (183) microg in old subjects; mean (SE), P0.01], while NO did not. In addition, breath NO was strongly influenced by ambient NO, which varied greatly. N2O maximum level in old subjects after ingesting lettuce was higher than that of young subjects (750 vs. 1092 ppb, P0.05), and significantly higher N2O concentration levels were seen at 30, 45, 60, and 105 min in old subjects.A large amount of N2O produced in the intestine and normal nitrate intake do not influence the breath NO concentration, probably due to its relatively small production. Higher maximum N2O concentration after ingesting lettuce in old subject is probably because more bacteria, which rapidly reduce dietary nitrate in the upper intestinal tract, inhabit the gut in old age. Our results suggested that breath N2O is a useful noninvasive maker to estimate dietary nitrate reduction in the intestinal tract.

This study was conducted to determine whether and under what circumstances exercise causes nausea. Twelve healthy volunteers (20-37 years), including six athletes, participated in the study. Subjects were studied on seven occasions. Each subject performed low and high-intensity exercise without eating, immediately after eating a beef patty and 60 min after eating. Besides these exercise experiments, effect of meal on nausea was studied in each subject for 180 min without exercise. Exercise was done on a bicycle ergometer for 60 min at 40-50% maximal heart rate reserve and 20 min at 70-80% maximal heart rate reserve. Subjects were tested for nausea by visual analogue scales. Both low and high-intensity exercise caused nausea. Scores for nausea were greater during exercise at fasting state and immediately after eating than those without exercise (p0.05 during low-intensity exercise, and p0.01 during high-intensity exercise). Immediately after eating, scores for nausea were greater during high-intensity exercise than during low-intensity exercise (p0.05). During high-intensity exercise, scores for nausea were greater immediately after eating than without eating (p0.05). There were no differences in ratings for nausea between the sexes in any of the experimental conditions. Training did not decrease exercise-induced nausea. In conclusion, exercise causes nausea, the severity of which is related to exercise intensity and food intake, but not sex differences nor physical training.

Trace gases in exhaled air have been used as a simple means of assessing metabolic reactions. The investigations of trace gases derived from bacteria in human exhalation are usually hydrogen (H2) or methane (CH4). On the other hand, nitrous oxide (N2O) is also derived from microorganisms, especially denitrifying bacteria. Although many kinds of denitrifying bacteria have been isolated on and in the human body, there has been few concerning N2O. We studied 222 healthy people from the age of 5 to 85 years. The analysis of N2O in exhaled air was carried out by a infrared-photoacoustic (IR-PAS) analyzer. It was found that N2O ranged from 0 to 1670 ppbv in exhaled air and that 59% (131) of the subjects were producers of N2O. A highly significant relationship was observed between age and concentrations of N2O (r = 0.40, P0.01). The rate of production in young children and in the aged was significantly higher than that in adults aged 20-39 years (P0.01), and less than 30% were producers during puberty. The change of normal microflora on and in human body with aging may have caused the significant relationship between age and emissions of N2O.