Mechanistic Study of the Solvent-Dependent Formation of Extended and Stacked Supramolecular Polymers Composed of Bis(imidazolylporphyrinatozinc) Molecules.

Bis(imidazolylporphyrinatozinc) molecules linked through a 1,3-butadiynylene moiety respond to the solvents they are dissolved in to afford exclusively extended (E) or stacked (S) supramolecular polymers. This system is expected to be a solvation/desolvation indicator. However, the principles underlying the solvent-dependent formation of the two types of polymers and the mechanism of the transformation between them are unclear. The formation of the polymers is considered to depend on the two types of complementary coordination bonds that can be formed and the π-π interactions between the porphyrins. In this study, the contributions and solvent dependence of both the coordination bonds and the π-π interactions have been investigated. The results clearly indicate that the coordination bonds are weakly or little solvent-dependent, and that the π-π interactions function effectively only in the inner porphyrins of the S-polymer and are strongly solvent-dependent. Thermodynamic analysis revealed that the formation of the E- or S-polymer in solution is determined by the total energies and the type of solvent used. The transformation of the E- to S-polymer was investigated by gel permeation chromatography. The kinetics of the transformation were also determined. The role of the terminal imidazolylporphyrinatozinc moieties was also investigated: The results indicate that the transformation from the E- to S-polymer occurs by an exchange mechanism between the polymers, induced by attack of terminal free imidazolyl groups on a polymer to zinc porphyrins on other polymers.

A Solvation/Desolvation Indicator Based on van der Waals Interactions between Solvents and Porphyrins.

Solvation is a ubiquitous phenomenon associated with molecules in solutions. It often determines the equilibria of molecular systems and the rates of chemical reactions. Van der Waals interactions (a general term) includes weak interactions among noncharged compounds and it contributes significantly to solvation. The distinct observation of van der Waals interaction between solvent and porphyrin derivatives is reported herein. Bis(imidazolylporphyrinatozinc) structures connected through a 1,3-butadiyne moiety give two types of coordination polymers, E (extended) and S (stacked) polymers, exclusively. E polymers have larger solvent-accessible surface areas than the corresponding S polymers. Therefore, E polymers are better solvated than S polymers, providing an indicator of solvation and desolvation for the solvents used. A simple method (like a litmus test) was developed to evaluate the solvation ability of various solvents. Sixty-seven solvents and liquid compounds were tested, under the same conditions, using a conventional UV/Vis spectrometer. The results revealed a new liquid group with high solvation ability towards the porphyrins, and clarified van der Waals interaction assisted by secondary interaction on the substituents. The indicator system should contribute to the solution chemistry of molecules and materials, and to supramolecular chemistry interactions among hetero components.

Tongue Strength is Associated with Grip Strength and Nutritional Status in Older Adult Inpatients of a Rehabilitation Hospital.

The aim of this cross-sectional study was to investigate whether tongue strength observed in older adult inpatients of a rehabilitation hospital is associated with muscle function, nutritional status, and dysphagia. A total of 174 older adult inpatients aged 65 years and older in rehabilitation (64 men, 110 women; median age, 84 years; interquartile range, 80-89 years) who were suspected of having reduced tongue strength due to sarcopenia were included in this study. Isometric tongue strength was measured using a device fitted with a disposable oral balloon probe. We evaluated age, muscle function as assessed by the Barthel index and grip strength, nutritional status as measured by the Mini Nutritional Assessment-short form (MNA-SF), body mass index, serum albumin, controlling nutritional status, and calf circumference and arm muscle area to assess muscle mass. In addition, the functional oral intake scale (FOIS) was used as an index of dysphagia. Multivariate linear regression analysis revealed that isometric tongue strength was independently associated with grip strength (coefficient = 0.33, 95 % confidence interval (CI) 0.12-0.54, p = 0.002), MNA-SF (coefficient = 0.74, 95 % CI 0.12-1.35, p = 0.019), and FOIS (coefficient = 0.02, 95 % CI 0.00-0.15, p = 0.047). To maintain and improve tongue strength in association with sarcopenic dysphagia, exercise therapy and nutritional therapy interventions, as well as direct interventions to address tongue strength, may be effective in dysphagia rehabilitation in older adult inpatients.

Role of infected grandmothers in transmission of Helicobacter pylori to children in a Japanese rural town.

AIM: Although the prevalence of Helicobacter pylori (H. pylori) increases with age and the main period of acquisition is childhood, the route of transmission of H. pylori infection remains unclear. This study aims to evaluate the relationship between prevalence of children and grandparents. METHODS: A total of 838 consecutive children who attended the Urita clinic and whose blood was taken for work up were enrolled in the present study. They were 449 boys and 389 girls, with a mean age of 12.4 years. H. pylori serology of their family members who were living together in one house was picked up to analyse intra-familial clustering of H. pylori infection. The family members of these children consisted of 448 fathers, 597 mothers, 205 grandfathers, 361 grandmothers and 589 siblings. RESULTS: The seropositive rates of mothers, grandmother and siblings in seropositive children were significantly higher than those in seronegative children. H. pylori infection in mothers and grandmothers was a marked risk factor for infection in the index children. Larger family size was not a risk factor for H. pylori infection. In contrast, having an infected father or grandfather was not an independent predictor for children infection. CONCLUSIONS: Our data demonstrate that not only mother-to-child transmission but also grandmother-to-child transmission is an important mechanism for the spread of H. pylori in a three-generation household.

Genotyping of skin and soft tissue infection (SSTI)-associated methicillin-resistant Staphylococcus aureus (MRSA) strains among outpatients in a teaching hospital in Japan: application of a phage-open reading frame typing (POT) kit.

We aimed to elucidate the current epidemiological features of outpatient skin and soft tissue infection (SSTI)-associated methicillin-resistant Staphylococcus aureus (MRSA) in Japan. Altogether, we evaluated the performance of a phage-open reading frame typing (POT) kit for genotyping these MRSA strains. We collected 57 MRSA strains from all outpatients with SSTIs attending a teaching hospital in Japan. Drug susceptibility measurement and genotyping including SCCmec typing, spa typing, multilocus sequence typing, pulsed-field gel electrophoresis, and commercial POT-kit were performed. The majority of strains (39 strains, 68 %) had the SCCmec-II element. Seventeen strains (30 %) with SCCmec-IV accounted for the second largest population. Strains with SCCmec-IV and SCCmec-V appeared multiclonal, and a predominance of Panton-Valentine leukocidin (PVL) gene-negative CC8/spa-CC008 strains, as well as the first isolate of an ST93 strain in Japan, was observed among them. Only one USA300 strain was identified. Strains with SCCmec-IV and SCCmec-V were significantly susceptible to antimicrobials. The PVL gene was found in 5 SCCmec-IV strains and 1 SCCmec-V strain. The POT-kit successfully predicted the SCCmec type in 54 strains (95 %), and typing by POT1 scores was highly concordant with SCCmec typing and spa typing. Moreover, three PVL-positive strains fell into a particular POT type (POT scores, 106-77-113). Simpson's index of the POT-kit was 0.977. In conclusion, the present study clarified the multiclonal nature of outpatient SSTI-associated MRSA in a teaching hospital in Japan. These data also underscore the utility of the POT-kit for non-outbreak surveillance through its simple platform consisting of two multiplex PCRs without sequencing.

Effects of a soybean nutrition bar on the postprandial blood glucose and lipid levels in patients with diabetes mellitus.

We investigated the influence of a soybean nutrition bar made from whole soy powder on the blood glucose, insulin and lipid levels in comparison with a test cookie with the same amount of energy in patients with diabetes mellitus. In the cross-over designed study, meal tolerance tests using the soybean nutrition bar and test cookie were performed. Two kinds of test meals were used: Study 1 80 kcal, Study 2 592 kcal. The blood glucose response was significantly lower in the soybean nutrition bar trial than in the cookie trial (Studies 1 and 2, p < 0.001). The blood insulin response was also significantly lower in the soybean nutrition bar trial than in the cookie trial (Study 2, p < 0.001). The blood triglyceride and non-esterified fatty acid responses were not significantly different between the two trials, nor were the changes in breath H2 enrichment (Study 2). The soybean nutrition bar did not induce postprandial hyperglycaemia in diabetic patients unlike the isoenergetic test cookies.

Effects of the traditional Japanese medicine Rikkunshito on postprandial glucose and lipid metabolism.

BACKGROUND/AIMS: Rikkunshito, a traditional Japanese medicine, has been used as a prokinetic agent to treat functional dyspepsia. Acceleration of gastric emptying of a meal may have a great impact on postprandial blood glucose and insulin responses, possibly resulting in lipid metabolism. The aim of the present study was to investigate associations between blood glucose and insulin levels and GLP-1 response after administration of solid test meals. Effects of Rikkunshito on glucose and lipid metabolism were also evaluated. METHODOLOGY: A meal challenge test (cookie test) was performed on 11 healthy volunteers. RESULTS: Two-week intake of Rikkunshito did not affect postprandial glucose, GLP-1, triglyceride, or RLP-c responses, whereas the plasma insulin level at 60 min was significantly higher after intake of Rikkunshito. FFA levels were also lower from 60 min to 180 min after intake of Rikkunshito. This suggests that GLP-1 does not contribute to enhanced insulin secretion at 60 min after ingestion of solid test meals. It is likely that a prokinetic effect of Rikkunshito could alter insulin secretion after ingestion of solid test meals. CONCLUSIONS: Rikkunshito enhances insulin secretion at 60 min after taking solid meals and subsequently reduces plasma FFA levels. These may contribute to preventing metabolic syndrome.

Measurement of Solvation Ability of Solvents by Porphyrin-Based Solvation/Desolvation Indicators.

A new solvent scale, solvation ability (SA), was developed to arrange solvents in the order of their SA for large π-conjugated compounds. The SA of a solvent was determined in a binary solvent system of an assessed solvent and a standard "good" solvent (GS) or "poor" solvent (PS), chloroform or methylcyclohexane, respectively, in the presence of two types of solvation/desolvation indicators, 1Zn2 and 2Zn2 . The latter comprises bis(imidazolylporphyrinatozinc) linked via a 1,3-butadiynylene moiety having linear alkyl and hydrophilic side chains, respectively. GSs and PSs give extended (E-) and stacked (S-) supramolecular polymers of the indicators, respectively. SA values are defined as vol % of the standard solvent added to an assessed solvent to give the balance point where comparable amounts of E- and S-polymers of the indicators coexist. GSs and PSs have positive and negative signs, respectively. In this study, the SA of 25 solvents was determined. The SA values with indicator 1Zn2 were as follows: ethyl acetate (-81), hexane (-66), toluene (-50), cyclohexane (-47), CCl4 (-25), chloroform (50), and nitrobenzene (79).

Form of gastric air bubble is associated with gastroesophageal reflux symptoms.

BACKGROUND/AIMS: Gastric bubble is present in approximately 70% of normal chest and abdominal radiograph. Most swallowed air is regurgitated and belching is a physiological phenomenon to expel ingested gas from the stomach and is a common symptom in normal adults. In the present study it was investigated whether gastric bubble detected on abdominal radiograph is associated with GERD symptoms. METHODOLOGY: All of the patients who first attend our hospital were asked to respond the F-scale questionnaire regardless of their chief complaints to diagnose GERD. Plain abdominal films in the erect position were used to measure the size of gastric bubble and to classify the form of gastric bubble into four groups: dome-type; irregular-type; stomach-type; and undetected-type. The quantity of gastric bubble (gastric bubble score) was determined as the pixel value on image collected from hospital's digital database. RESULTS: The gastric bubble score of irregular-type was significant lower than that of dome-type and stomach-type. GERD was most frequently detected in stomach-type group, followed by undetected-type, irregular-type, and dome-type. The mean score of F-scale was significantly higher in stomach-type than in dome-type. CONCLUSIONS: It is concluded that gastric bubble detected on plain abdominal films is an informative marker for evaluating the functional disorder of upper digestive tracts. Physicians have to recognize the importance of plain films of the abdomen in the diagnostic process of GERD.

[Human parvovirus B19 infection in 15 adults--two-year Toho University Hospital study].

Human parvovirus B19 infection in adults features clinical symptoms and laboratory abnormal findings unlike those in children commonly associated with cheek rash. We diagnosed 15 adult cases based on the positive increase in anti-parvovirus B19 IgM antibody (8.89 +/- 7.86 mean +/- SD, enzyme immunoassay (EIA)). Antibody titer was measured in 78 patients clinically showing fever, edema, exanthema, arthralgia, and myalgia among 11,040 outpatients first visiting the hospital from January 2005 to December 2007. Based on clinical and laboratory findings for these 15 cases, we recommended that physicians taking anti-parvovirus B19 antibody blood samples note whether (1) the level of C reactive protein is negative or low and without leucocytosis; (2) a miliary rash is observed in short duration (rarely facial); (3) arthralgia and/or myalgia is present in the extremities (sometimes asymmetrical); (4) edema is present in the extremities, especially finger, ankle, or sole of the foot; (5) contact has been made with ill children; (6) flu-like symptoms occur such as fatigue, headache, or fever;and (7) normo- or hypocomplementemia and/or antinuclear antibody is positive. Patients who fulfill requirement (1) plus at least three of requirements (2) through (7) should have a blood sample taken. We retrospectively studied 78 cases using these requirements, finding their sensitivity to be 100% (15/15), specificity to be 88.9% (56/63), positive predictive value to be 68.1% (15/22) and negative predictive value to be 100% (56/56). These requirements are thus useful in selecting patients for measuring antibody titer and definitively diagnosing severe or persistent parvovirus B19 infection occationally observed in adults.

Is the metabolism of toast alcohol beverages influenced by a meal taken five minutes later?

Alcohol is commonly consumed with, or soon after, a meal that affects gastric emptying and thus, absorption and metabolism of alcohol. The aim of this study is to evaluate the effect of liquid test meal ingested soon after, alcohol ingestion on alcohol metabolism, as is common in the social setting. First, a 100 mL of water containing of 80 mg of 13C-ethanol was administrated orally in 7 healthy subjects, and 200 mL of liquid meal (200 kcal) was administrated 5 min after alcohol ingestion. Breath samples were taken at baseline and at 10-min interval for 150 min. Next, 13C-ethanol breath test was performed without ingestion of liquid meal. Cmax was decreased after ingestion of liquid meal, whereas Tmax was unchanged. The descending gradient of 13CO2 excretion curves after ingestion of liquid meal is parallel to that without liquid meal, while the ascending gradient of 13CO2 excretion curves in the first 10 min had a tendency to be greater after ingestion of liquid meal than without ingestion of liquid meal. A significant delay in breath 13CO2 excretion after ingestion of liquid meal was found and the AUC values were lower after ingestion of liquid meal in each time point, indicating that liquid meal ingested soon after alcohol ingestion may not affect elimination but absorption and/or metabolism of a small amount of alcohol.

Saliva transit from the oral cavity to the esophagus in GERD.

BACKGROUND/AIMS: Normal esophageal acid clearance depends on the neutralization of acid by swallowed saliva, as well as on esophageal peristalsis. This study therefore aimed to investigate the association between saliva production and transport from the oral cavity to the esophagus and developing gastroesophageal reflux disease (GERD) METHODOLOGY: Twenty-eight consecutive patients with GERD symptoms by gastroesophageal reflux self-report questionnaires and 13 healthy volunteers were recruited in the study. After intravenous administration of 99mTc-pertechnetate, anterior sequential imaging was performed every minute for 40 minutes. At 20 minutes after injection of radionuclide, a lemon candy was administered intra-orally to stimulate salivary secretion. Regions of interest (ROI) were selected on the individual oral cavity, the pharynx, and the upper esophagus and time activity curves were drawn for each of these. A time-activity curve in each ROI was subjectively graded, as zero to two-point. The sum of scores in 3 ROIs was considered as a saliva transit total score. RESULTS: The mean transit score of the oral cavity did not differ significantly between GERD patients and healthy volunteers (1.38 vs. 1.61), whereas significantly lower transit scores of pharynx and upper esophagus were found in GERD patients. A 0-point saliva transit score of pharynx and upper esophagus was significantly more frequently detected in GERD patients than in healthy volunteers. CONCLUSIONS: This new modification of saliva scintigraphy is able to evaluate the esophageal motility simply, without a test meal, and to detect impaired saliva transit between pharynx and upper esophagus in GERD patients non-invasively.

Extensive atrophic gastritis linked to increased levels of intraluminal hydrogen gas.

BACKGROUND/AIMS: Gastric acid plays an important part in the prevention of bacterial colonization of the gastrointestinal tract. If these bacteria have an ability of hydrogen (H2) fermentation, intraluminal H2 gas might be detected. We attempted to measure the intraluminal H2 concentrations to determine the bacterial overgrowth in the gastrointestinal tract. METHODOLOGY: Studies were performed in 647 consecutive patients undergoing upper endoscopy. At the time of endoscopic examination, we intubated the stomach and the descending part of the duodenum without inflation by air, and 20 ml of intraluminal gas samples of both sites was collected through the biopsy channel. Intraluminal H2 concentrations were measured by gas chromatography. RESULTS: Over all, intragastric and intraduodenal H2 gas was detected in 566 (87.5%) and 524 (81.0%), respectively. The mean values of intragastric and intraduodenal H2 gas were 8.5 +/- 15.9 and 13.2 +/- 58.0 ppm, respectively. The intraduodenal H2 level was increased with the progression of atrophic gastritis, whereas the intragastric H2 level was the highest in patients without atrophic gastritis. CONCLUSIONS: The intraduodenal hydrogen levels were increased with the progression of atrophic gastritis. It is likely that the influence of hypochlorhydria on bacterial overgrowth in the proximal small intestine is more pronounced, compared to that in the stomach.

Retroperitoneal lymphangioleiomyomatosis associated with endosalpingiosis.

A case of retroperitoneal lymphangioleiomyomatosis (LAM) arising from endosalpingiosis is described. A 25-year-old woman with no history of tuberous sclerosis or hormonal therapy presented with a painless, palpable abdominal mass. Computed tomographic and magnetic resonance imaging studies of the abdomen demonstrated a 4 cm cystic mass in the retroperitoneum. Macroscopically, the excised retroperitoneal cyst was multilocular and measured 4.0 x 3.5 x 3.5 cm. Histologically, the lesion demonstrated three components. The first comprised multiple cysts or glands lined by columnar epithelial cells with cilia. The second component was a condensation of small stromal cells immediately subjacent to the cystic epithelium or glands. The third component was a thick exterior wall composed of plump spindle cells with clear to palely eosinophilic cytoplasm in a fascicular pattern, and slit-like vascular spaces, resembling LAM. Immunohistochemically, the epithelium and glands were positive for cytokeratin 7. The stromal cells were positive for vimentin and CD10. The cells of the LMA-like component showed positive staining for HMB45, alpha-smooth muscle actin, muscle actin and h-caldesmon. The lesion, LAM arising from endosalpingiosis, represents a distinctive pathologic entity that should be recognized and studied further. This type of lesion should be included in the differential diagnosis of retroperitoneal cystic lesions.

Gastroesophageal reflux disease symptoms are more common in general practice in Japan.

AIM: To accurately assess the prevalence of GERD symptoms in general practice. METHODS: 4139 consecutive patients (2025 men and 2114 women with a mean age of 43 years), who first attended the Outpatient Department of General Medicine and Emergency Care at Toho University Omori Hospital, were asked to respond to the F-scale questionnaire regardless of their chief complaints. The questionnaire is a self-report instrument, written in a simple and easy-to-understand language, containing 12 questions. RESULTS: Of 4139 subjects, 1554 patients (37.6%) were identified as GERD according to their F-scale score (> 7). However, there were only 45 consultations (1.1%) for typical GERD symptoms. Although GERD symptoms are common in adults of all ages, the prevalence of GERD was highest in the 20-29 years age group and the age group 70-79 years had the lowest prevalence for both males and females. CONCLUSION: Although there was a high rate indicating GERD in our primary care population, only 1.1% of outpatients attended our hospital with a chief complaint of GERD symptoms. Since about one-third of GERD patients are affected by atypical symptoms, general physicians need to be cautious about extrapolating these results to patients with a chief complaint other than typical GERD symptoms.

Ten-second endoscopic breath test using a 20-mg dose of 13C-urea to detect Helicobacter pylori infection.

BACKGROUND/AIMS: Attempts to improve the 13C-urea breath test (UBT) have focused on decreasing the amount of substrate used and reducing the duration of the test. To render the test less expensive and more convenient, we designed a more rapid and less expensive endoscopic UBT with a low dose of 20 mg and a shortened measurement time. METHODOLOGY: A total of 178 patients who underwent diagnostic upper endoscopy were enrolled. At endoscopy, 150 mL of intragastric gas sample were collected through a biopsy channel. Following inflation with air, 20 mL of water containing 20 mg of 13C-urea were sprayed onto the gastric mucosa using a spraying instrument. After 10 seconds, a gastric gas sample was collected again. The standard UBT was performed after 3-10 days. RESULTS: The delta13CO2 values of intragastric samples in H. pylori-positive patients and H. pylori-negative patients were 76.7 +/- 132.9 per thousand and 1.6 +/- 1.2 per thousand, respectively. With intragastric samples, the maximum sensitivity and specificity of intragastric samples were 83.7% and 100% with cut-off point of 8 per thousand, respectively. CONCLUSIONS: Ten-second endoscopic UBT using a 20-mg dose of 13C-urea is a rapid, inexpensive, and accurate method for the detection of H. pylori infection in clinical practice.

Endoscopic 13C-urea breath test for detection of Helicobacter pylori infection after partial gastrectomy.

BACKGROUND/AIMS: It is difficult to interpret the results of 13C-urea breath test (UBT) in gastrectomy patients because the test urea may pass through the stomach faster. The aim of this study is to evaluate the efficacy of the modified endoscopic UBT for detection of Helicobacter pylori (H. pylori) infection in the residual stomach. METHODOLOGY: An endoscopic UBT was performed in 44 patients who had undergone partial gastrectomy. At endoscopy, 20 mL of water containing 100mg of 13C-urea were sprayed onto the gastric mucosa and an intragastric gas sample was immediately collected through the biopsy channel. Breath samples were collected at 20 min after spraying 13C-urea. RESULTS: The intragastric delta13CO2 value in H. pylori-positive patients was significantly higher than those of 20-minute breath samples. The maximum sensitivity and specificity of intragastric samples were 97% and 100% with cutoff point of 5 per thousand, respectively. The sensitivity and specificity of breath samples at 20 min were 71.4% and 66.7% with cutoff point of 0.6 per thousand, respectively. CONCLUSIONS: An endoscopic UBT was superior to a standard UBT to detect H. pylori infection after partial gastrectomy.

High incidence of fermentation in the digestive tract in patients with reflux oesophagitis.

OBJECTIVES: Because bacteria represent the sole source of gut hydrogen (H2) and methane (CH4), fasting breath H2 and CH4 gases have been used as markers of colonic fermentation. The presence of carbohydrates in the colonic lumen inhibits gastric and pancreatic secretions, and also influences lower oesophageal sphincter function in gastro-oesophageal reflux disease. MATERIALS AND METHODS: Studies were performed in 793 consecutive patients undergoing oesophagogastroscopy (270 men and 523 women, aged 19-85 years). A fasting breath sample (20 ml) was collected before endoscopy. At endoscopy, we intubated the stomach without inflation by air, and 20 ml of intragastric gas was collected through the biopsy channel. Next, the tip of the endoscope was inserted into the second portion of the duodenum without inflation by air, and 20 ml of intraduodenal gas was collected. H2 and CH4 concentrations of each sample were measured by gas chromatography. RESULTS: Reflux oesophagitis was found in 147 of the 793 patients. The mean values of the H2 and/or CH4 levels of samples taken from the stomach, duodenum and exhaled air were higher in patients with reflux oesophagitis than those without reflux oesophagitis. High H2 and/or CH4 levels were more frequently found in patients with reflux oesophagitis. CONCLUSIONS: We concluded that the presence of fermentation in the digestive tract was considered to be a risk factor for developing reflux oesophagitis.

Hydrogen and methane gases are frequently detected in the stomach.

AIM: To investigate the incidence of bacterial overgrowth in the stomach by using a new endoscopic method in which intragastric hydrogen and methane gases are collected and analyzed. METHODS: Studies were performed in 490 consecutive patients undergoing esophagogastroscopy. At endoscopy, we intubated the stomach without inflation by air, and 20 mL of intragastric gas was collected through the biopsy channel using a 30 mL syringe. Intragastric hydrogen and methane concentrations were immediately measured by gaschromatography. H pylori infection was also determined by serology. RESULTS: Most of intragastric hydrogen and methane levels were less than 15 ppm (parts per million). The median hydrogen and methane values (interquartile range) were 3 (1-8) ppm and 2 (1-5) ppm, respectively. The high hydrogen and methane levels for indication of fermentation were decided if the patient had the values more than 90 percentile range in each sample. When a patient had a high level of hydrogen or methane in one or more samples, the patient was considered to have fermentation. The overall incidence of intragastric fermentation was 15.4% (73/473). Intragastric methane levels were higher in the postoperative group than in other groups. None of the mean hydrogen or methane values was related to H pylori infection. CONCLUSION: Hydrogen and methane gases are more frequently detected in the stomach than expected, regardless of the presence of abdominal symptoms. Previous gastric surgery influences on the growth of methane-producing bacteria in the fasting stomach.

Seventy-five gram glucose tolerance test to assess carbohydrate malabsorption and small bowel bacterial overgrowth.

AIM: To investigate non-invasively the incidence of absorption of carbohydrates in diabetic patients during an oral glucose tolerance test (OGTT) and to determine whether malabsorption may be associated with insulin secretion and insulin resistance. METHODS: A standard 75-g OGTT was performed in 82 diabetic patients. The patients received 75 g of anhydrous glucose in 225 mL of water after an overnight fasting and breath samples were collected at baseline and up to 120 min after ingestion. Breath hydrogen and methane concentrations were measured. Blood glucose and serum insulin concentrations were measured before ingestion and at 30, 60, 90, 120 min post-ingestion. RESULTS: When carbohydrate malabsorption was defined as subjects with an increase of at least 10 ppm (parts per million) in hydrogen or methane excretion within a 2-h period, 28 (34%) had carbohydrate malabsorption. According to the result of increased breath test, 21 (75%) patients were classified as small bowel bacterial overgrowth and 7 (25%) as glucose malabsorption. Patients with carbohydrate malabsorption were older and had poor glycemic control as compared with those without carbohydrate malabsorption. The HOMA value, the sum of serum insulin during the test and the Delta insulin/Delta glucose ratio were greater in patients with carbohydrate malabsorption. CONCLUSION: Insulin resistance may be overestimated by using these markers if the patient has carbohydrate malabsorption, or that carbohydrate malabsorption may be present prior to the development of insulin resistance. Hence carbohydrate malabsorption should be taken into account for estimating insulin resistance and beta-cell function.