Human clinical studies have yielded a great number of findings on the suppressive effect of indigestible dextrin on glucose absorption. The suppressive effect tends to be marked in subject groups whose blood glucose is at high levels in blood tests and the degree of suppression may vary depending on the saccharide species used for loading. The following is a summary review of the suppressive effect of indigestible dextrin as reported in scientific papers. 1) In starch loading tests, although a significant difference in the degree of blood glucose suppression by indigestible dextrin is seen in groups whose blood glucose values after placebo ingestion are higher than average, no such difference is commonly observed in low-value groups. 2) When groups with high and low blood glucose values before testing are classified in the same starch loading study, however, a significant difference is observed even in low-value groups, as the low-value group includes subjects in the placebo group with higher blood glucose values showing higher peak values at testing. 3) In sucrose loading tests, the significant difference was observed more clearly not only in high-value groups but also in low-value groups. Since the inhibitory action of indigestible dextrin is strong on α-glucosidase when it binds to sucrose in order to hydrolyze into glucose and fructose, it appears certain that suppression of glucose absorption into the blood takes place. 4) When maltose loading was carried out in twelve healthy young subjects (mean age: 21.4±0.51) in a preliminary study, there was a significant difference in the degree of blood glucose suppression in the groups with higher than average blood glucose level. However, no significant difference was found in another test, in which maltose was loaded to 13 adult subjects (mean age: 54.4±5.5). Although the glucose absorption at maltose hydrolysis in α-glucosidase reaction may be inhibited by indigestible dextrin like as that at starch hydrolysis, the results of the maltose loading test were varied. 5) Since α-glucosidase is distributed over the small intestine wall, in order to inhibit co-transportation of the glucose into the blood in the hydrolysis of disaccharide by α-glucosidase, it is necessary for indigestible dextrin to also be distributed quickly over the same small intestine wall. If the loaded foods are taken in slowly, blood glucose level will describe a gradually increasing curve over time; similarly, if indigestible dextrin is taken in slowly, the distribution of the indigestible dextrin to the intestinal wall will be slow and inefficient for inhibition of glucose absorption.
Diarrheagenic Escherichia coli (DEC) is an important group of pathogens associated with enteric diseases. Diffusely adherent Escherichia coli (DAEC) strains are currently considered to constitute a sixth group of DEC. Although recent epidemiological studies have shown a high prevalence of DAEC strains among strains isolated from infant diarrheal stools, their involvement remains a matter of debate. Both commensal and pathogenic strains can be classified as Afa/Dr DAEC isolates since DAEC strains have been identified based on their diffuse adherence (DA) to cultured epithelial cells and on the detection of afa/dra/daa related operons encoding the DA phenotype. Measuring diffuse adhesion alone is insufficient to evaluate the diarrheagenicity of strains and other distinguishing characteristics are needed. In order to elucidate the pathophysiological processes by which Afa/Dr DAEC strains induce diarrhea, the present review focuses on the Afa/Dr adhesin and the various cell signaling events that occur after epithelial cells have been infected by Afa/Dr DAEC.
Food irradiation is an effective physical process for decontamination of fresh foods, sprout inhibition of potatoes and onions, and disinfestation of agricultural grains utilizing the ionizable energy of gamma-rays, X-rays, and electron beams. The wholesomeness - a combined notion of toxicological, microbiological, and nutritional suitability - of irradiated foods has been authorized by WHO and other international organizations. Research into the safety of alkylcyclobutanones, a newly detected unique radiolytic product in irradiated foods, is now in progress. Food irradiation has already been cleared in at least 51 countries and more than 400,000 tons of foods are commercially irradiated in at least 16 countries including China, the USA, and Asian countries. Spices and herbs are the main products for food irradiation to eliminate pathogens. However, in Japan, only potato irradiation for sprout inhibition has so far been cleared, and approximately 8,000 tons of irradiated potatoes are distributed on the Japanese market every year. All Nippon Spice Association, the Japanese spice industry association, has been submitting petitions for the approval of spice irradiation for decontamination to the Ministry of Health, Labor and Welfare for more than 10 years. TL analysis and alkylcyclobutanone analysis have already been authorized as official irradiation detection methods in the inspection of imported foods. Anti-food irradiation groups are still active and consumers also have vague concerns over the use of irradiation in food processing in Japan. In order to progress to a solution, public information activities using simple explanations are very important.
Light-to-moderate alcohol drinking reduces the risk of atherosclerotic diseases such as coronary heart disease, ischemic-type stroke, and peripheral artery disease through the anti-atherosclerotic and anti-thrombotic effects of alcohol. These beneficial effects of alcohol are explained mainly by its blood lipid-improving actions, such as HDL cholesterol-increasing and LDL cholesterol-decreasing actions, and by its blood coagulation-suppressing actions, such as platelet aggregation-inhibiting, blood fibrinogen-decreasing, and plasminogen activator-increasing actions. These biological actions of alcohol are thought to be independent of the type of beverage and to be due to ethanol itself. On the other hand, excessive drinking and binge drinking increase the risk of hypertension, hemorrhagic-type stroke, arrhythmia, and cardiomyopathy. The guidelines of the international and Japanese societies of hypertension recommend that alcohol intake should be restricted to less than two drinks (24 g ethanol) per day in men and one drink (12 g ethanol) per day in women. Alcohol drinking should never be recommended for promotion of health in those who are currently nondrinkers since there is no way of predicting the future likelihood of excessive drinking and addiction. Moreover, individual background factors such as age, gender, body weight, history of smoking, history of hypertension therapy, and polymorphism of alcohol-metabolizing enzymes should be taken into account when considering alcohol intake volume suitable for each individual. The etiology of alcohol-induced hypertension and cardiomyopathy remains to be clarified. Future studies are also needed to determine whether light-to-moderate alcohol drinking is permissible in persons with atherosclerotic disease and in persons with risk factors for atherosclerosis.
The Environmental Quality Standards for Water in Japan, established in 1971, have been revised 16 times in the past. The main content of the revisions consisted of addition of standard items, tightening of standard values, and change in measurement methods. To judge the level of attainment of the standards, which have been growing stricter, knowledge and proficiency in the appropriate measurement of the water environment are important. The present review, which focuses on the measurement methods for each standard item and gives an overview of the history and points of revision of the standards, will contribute to analyzing and understanding actual conditions in the water environment.
In order to assess the safety of electronic cigarettes, 32 smokers who consume more than 20 tobacco cigarettes daily were enrolled in the present study. The cartridge of an electronic cigarette contains 0.25 g of glycerin aqueous solution. Each participant was asked to consume one filter cartridge per day (more than 150 puffs per day) for 4 weeks. Following the treatment, no abnormal changes in blood pressure, hematological data, or blood chemistry and no severe adverse events were observed. Although a trace amount of acrolein was detected in the vapor collected from a single filter cartridge, it was less than the minimum amount in the mainstream smoke from a single tobacco cigarette. During the use of the electronic cigarette, the daily consumption of tobacco cigarettes decreased significantly. This electronic cigarette containing glycerin aqueous solution may be a safe alternative to cigarette smoking.
The presence of Bt Rice, a genetically modified rice cultivated in China and including the Cry1Ac gene, was surveyed in thirty imported processed-rice foods in Osaka city, Japan, using published PCR methods. Twenty-nine of the processed-rice foods were negative for Bt rice, although it was difficult to detect rice taxon-specific DNA in one rice paper sample and impossible in one bifun (rice vermicelli) sample. We therefore judged the bifun sample not susceptible to examination and investigated the cause of the failure to detect rice taxon-specific DNA in it. DNA solution extracted from the bifun was diluted to 1, 2.5, 5, and 10ng/μL and used in PCR assay. As no amplification products were obtained in these dilutes, we considered that PCR reaction was not inhibited by impurities. Although the DNA extracted from the bifun was amplified to detect wheat, corn, and common plant DNA, no amplification products were detected. This suggested that DNA in the bifun had been degraded through food processing. Detection of rice taxon-specific DNA using the real-time PCR method was also carried out in the thirty imported processed-rice foods. When PCR reaction was performed at 50 cycles with a threshold of 0.1, the Ct value was 50 in the bifun, 46 in the rice paper, and 26 to 35 in the other processed-rice foods. Under the experimental conditions, there was not enough DNA extracted from the bifun or the rice paper to allow amplification of the rice taxon-specific DNA by PCR. The use of commercial DNA extraction kits was investigated with both the bifun and the rice paper. The detection rate of rice taxon-specific DNA was higher with the Genomic-tip 20/G ion-exchange type kit than with other DNA extraction kits, especially when α-amylase was not used.