Effect of predominant methanogenic flora on outcome of lactose hydrogen breath test in controls and irritable bowel syndrome patients of north India

The relationship between methanogenic flora and hydrogen (H(2)) production is considered to be a possible confounding factor in the interpretation of hydrogen breath tests (H(2)BT). Therefore, the present study was conducted prospectively and included 154 IBS patients (fulfilling Rome II criteria) and 286 age-and-sex-matched apparently healthy controls. Each subject underwent H(2)BT after overnight fasting using 25 g lactose. Methane and H(2) were measured using an SC Microlyser from Quintron, USA, at baseline and every 30 min for a total of 4 h. Subjects with fasting methane concentration <10 ppm were labeled as low methane producers (LMP) and >10 ppm as predominant methane producers (PMP). A rise >20 ppm over base line in hydrogen concentration was taken as +ve hydrogen breath test. IBS and control groups included 66.78% and 67.53% males, respectively. Mean age in the two groups were 48.52 +/- 30.54 years (range 15-68 years) and 45.67 +/- 30.54 years (range 15-78 years), respectively. Hydrogen breath test was +ve in 77/154 (50%) IBS patients and in 142/286 (49.65%) in controls (P > 0.05). It was also observed that the hydrogen breath test was -ve due to PMP in 5/77 (6.49%) of IBS patients and in 29/154 (20.14%) in controls. PMP affected lactose hydrogen breath tests in 6.49-20.14% subjects. This effect is more apparent in apparently healthy subjects as compared to patients with IBS.

Influence of previously ingested wheat on fasting breath hydrogen in celiac patients

The excretion of hydrogen in breath commonly persists, despite an overnight fast. Although the elevation of hydrogen concentration above the fasting value after the administration of a test sugar is evidence of malabsorption, the level of the fasting value itself in untreated celiac patients is unknown. Therefore, we studied the fasting breath hydrogen (FBH(2)) concentration in 40 healthy controls, 35 subjects with functional bowel disorders, and 30 patients of untreated celiac disease with and without bread or wheat diet one day before the test. The fasting level of hydrogen concentration in untreated celiac patients (28.7 +/- 19.5 ppm) was significantly higher than those in healthy volunteers (9.5 +/- 3.4 ppm) and subjects with functional bowel disorders (10.6 +/- 4.5 ppm). The percentage of patients with elevated H(2) fasting levels in untreated celiac disease (82.5%) was significantly higher than that in healthy controls (10%) and subjects with functional bowel disorders (17.1%). In 30 celiac patients, studied with and without wheat-free diet one day before the test, the fasting hydrogen levels decreased from 28.7 +/- 19.5 ppm to 10.6 +/- 3.5 ppm, and becoming normal in all patients of celiac disease. Our results show that the patients of untreated celiac disease should be instructed not to eat things made up of wheat one day before hydrogen breath testing so that the normal fasting hydrogen concentration can be obtained and false-negative hydrogen breath test results can be avoided.

Endoscopic balloon dilation in caustic-induced chronic gastric outlet obstruction

BACKGROUND

The standard treatment of caustic-induced gastric outlet obstruction (GOO) is surgery. There are only a few reports in the medical literature on endoscopic balloon dilation (EBD) for caustic-induced GOO.

OBJECTIVE

To study the short-term and long-term response of EBD in patients with caustic-induced GOO.

SETTING

Tertiary-care center in India.

DESIGN

Retrospective analysis of data.

PATIENTS

Of the 49 patients with caustic-induced GOO seen by us between January 1998 and December 2003, 41 were treated by EBD. Thirty-seven patients had consumed an acid and 4 had consumed an alkali a mean (SD) of 19.5 +/- 14.5 weeks earlier. EBD was performed every 3 weeks by using through-the-scope balloons under endoscopic guidance.

INTERVENTION

The balloon was negotiated across the narrowed segment and inflated for 60 seconds by using a pressure gun. Balloons of incremental diameters, up to a maximum of 3 sizes, were used in each sitting. The end point of dilation was 15 mm, after which patients were assessed for recurrence. The patients were observed until August 2007.

RESULTS

All 41 patients (23 men; mean [SD] age 29.6 +/- 8.5 years) could be successfully taken for EBD. Thirty-nine patients underwent successful repeated dilations, which required a mean (SD) of 5.8 +/- 2.6 dilations (range 2-13) to achieve the end point of 15 mm. All 39 patients were followed up for an average (SD) of 35.4 +/- 11.1 months (range 18-58 months). The mean (SD) size of the first dilator was 8.2 +/- 0.6 mm (range 8-10 mm). One patient had a perforation and was subjected to antrectomy; another patient had pain every time he received EBD; he also had surgery. Other complications were minor: self-limiting pain (n = 8) or bleeding (n = 7).

CONCLUSIONS

EBD is a safe, effective, and long-lasting alternative to surgery for caustic-induced GOO.

The effect of two levels of pressure support ventilation on tidal volume delivery and minute ventilation in preterm infants

OBJECTIVE

To study the effect of different levels of pressure support ventilation (PSV) on respiratory parameters in preterm infants during the weaning phase of mechanical ventilation.

DESIGN/METHODS

In this quasi-experimental crossover study, a total of 19 154 breaths were analysed from 10 ventilated infants of <32 weeks' gestation. Breath-to-breath data on minute ventilation, tidal volume, respiratory rate, peak inspiratory pressure and mean airway pressure were collected during three study epochs: synchronised intermittent mandatory ventilation (SIMV) alone, SIMV with partial PSV (PS(min)), and SIMV with full PSV (PS(max)). PS(min) was set to provide an exhaled tidal volume (V(Te)) between 2.5-4 ml/kg and PS(max) 5-8 ml/kg V(Te). Statistical analyses were performed using analysis of variance (ANOVA) for repeated measures.

RESULTS

The addition of full PSV (PS(max)) was associated with a significant increase in total minute ventilation as compared with SIMV alone (392 ml/kg/min vs 270 ml/kg/min, respectively; p<0.05). This difference in minute ventilation was still present when PS(min) was used (332 ml/kg/min as compared with 270 ml/kg/min in SIMV; p<0.05). There was also a concomitant decrease in the respiratory rate with both PS(max) (59 breaths per minute) and PS(min) (65 breaths per minute) compared with SIMV alone (72 breaths per min) (p<0.05).

CONCLUSIONS

Pressure support ventilation increases total minute ventilation and stabilises breathing in proportion to the level of pressure support used. This may be advantageous and provide a useful ventilation strategy for use during weaning stages of mechanical ventilation in preterm infants.

Complex dynamics in polymer nanocomposites

Polymer nanocomposites offer the potential to create a new type of hybrid material with unique thermal, optical, or electrical properties. Understanding their structure, phase behavior, and dynamics is crucial for realizing such potentials. In this work we provide an experimental insight into the dynamics of such composites in terms of the temperature, wave vector, and volume fraction of nanoparticles, using multispeckle synchrotron x-ray photon correlation spectroscopy measurements on gold nanoparticles embedded in polymethylmethacrylate. Detailed analysis of the intermediate scattering functions reveals possible existence of an intrinsic length scale for dynamic heterogeneity in polymer nanocomposites similar to that seen in other soft materials like colloidal gels and glasses.

Thickness induced structural changes in polystyrene films

Changes to the structure of polystyrene melt films as measured through the spectrum of density fluctuations have been observed as a function of film thickness down to the polymer radius of gyration (Rg). Films thicker than 4Rg show bulklike density fluctuations. Thinner films exhibit a peak in S(q) near q=0 which grows with decreasing thickness. This peak is attributed to a decreased interpenetration of chains resulting in an enhanced compressibility. Measurements were made using small angle x-ray scattering in a standing wave geometry designed to enhance scattering from the interior of the film compared to interface scattering.

Does every short stature child need screening for celiac disease?

AIM

To study the etiological profile of short stature at a tertiary care hospital in north India.

METHODS

In this prospective study, 176 children with short stature were enrolled from January 2005 to December 2006. Appropriate screening and definitive tests were performed to establish the etiology of short stature.

RESULTS

Celiac disease (CD) emerged as the single most common (15.3%) cause of short stature, followed by various endocrine disorders. It was interesting to note that none of the CD patients presented with gastrointestinal symptoms.

CONCLUSION

All short children should be screened for CD irrespective of gastrointestinal symptoms.

Cervical esophageal web and celiac disease

BACKGROUND AND AIM

There is paucity of prospective data on association between cervical esophageal webs and celiac disease. It is not clear whether all patients with cervical esophageal web need screening for celiac disease. Hence, the present study was carried out to determine the association of cervical esophageal web with celiac disease.

METHODS

This prospective study included consecutive patients with symptomatic cervical esophageal web diagnosed over a period of 4.5 years. Tissue transglutaminase antibody was measured in serum of each patient. Patients with elevated tissue transglutaminase antibody titer were subjected to esophagogastroduodenoscopy and biopsies were obtained from the descending duodenum to look for histological changes of celiac disease. Esophageal web was treated with bougie dilatation. Celiac disease was diagnosed on the basis of elevated tissue transglutaminase antibody and suggestive duodenal histology.

RESULTS

Twenty one patients were diagnosed to have cervical esophageal web. Eighteen (85.7%) had evidence of iron deficiency. Five (23.8%) patients with cervical esophageal web fulfilled criteria for diagnosis of celiac disease. All five had evidence of iron deficiency. None of these patients gave a history of chronic diarrhea. All patients were treated with bougie dilatation. Patients with celiac disease were advised of a gluten-free diet. All five celiac disease patients are free of dysphagia without recurrence after a mean follow up of 10 months (range: 3 to 16 months).

CONCLUSIONS

There is association between cervical esophageal web and celiac disease. All adult patients with cervical esophageal web and iron deficiency need screening for celiac disease even in the absence of chronic diarrhea.

Orocecal transit time in patients with celiac disease from North India: a case control study

AIM

The mechanisms responsible for bowel disturbances in celiac disease are still unknown. Small bowel motor abnormalities may be involved in this pathological condition; however, there is no study addressing small bowel transit in patients of celiac disease from Northern India.

METHOD

The mouth-to-cecum transit time was studied in 80 celiac patients and 80 age and sex matched apparently healthy controls.

RESULTS

Orocecal transit time in celiac patients was significantly delayed being 180+/-10.6 minutes (Mean+/-SE) as compared to 105+/-12.4 minutes in apparently healthy controls.

CONCLUSION

This prolonged orocecal transit time could be due to impaired small bowel function (deranged motility) in patients with celiac disease.

Squeeze-out of branched alkanes on graphite

We study squalane and heptamethylnonane (HMN) confined between a conducting atomic force microscope tip and a graphite surface. Solvation layering occurs for both liquids but marked differences in the squeeze out mechanics are observed for ordered or disordered monolayers. The squalane monolayer at 25 degrees C is an ordered solid, as verified by direct imaging, and the squeeze out can be modeled using elastic continuum mechanics. HMN is in a disordered state at 25 degrees C and cannot be modeled as a single elastic asperity even in solid-solid contact because HMN liquid is trapped in the contact zone.

Study of small intestinal bacterial overgrowth in North Indian patients with irritable bowel syndrome: a case control study

BACKGROUND

Approximately 20% of the general population has irritable bowel syndrome. Despite this high prevalence, the cause of irritable bowel syndrome is unknown. There is no data available concerning the prevalence of small intestinal bacterial overgrowth in North Indian patients with irritable bowel syndrome.

AIM

This study evaluated the prevalence of small intestinal bacterial overgrowth in patients with irritable bowel syndrome compared with healthy controls.

METHODS

This study included 225 consecutive patients of irritable bowel syndrome between the ages 20 and 65 years attending the gastroenterology clinics. Diagnosis of irritable bowel syndrome was made according to the Rome II criteria. Small intestinal bacterial overgrowth was estimated by using the non-invasive glucose hydrogen breath test.

RESULTS

Of 225 patients of irritable bowel syndrome, 160 (71.1%) were male and 65 (28.9%) were female. Of 100 controls, 65 (65%) were male and 35 (35%) female. The prevalence of small intestinal bacterial overgrowth was 25 of 225 (11.1%) patients with irritable bowel syndrome and 1 of 100 (1%) in apparently healthy controls. This difference was statistically significant. The prevalence of small intestinal bacterial overgrowth in male and female patients was not significantly different.

CONCLUSION

This study indicates that the prevalence of small intestinal bacterial overgrowth in irritable bowel syndrome patients from North India is approximately 11.1%, which is lower than the reported prevalence.

Traumatic orbitomaxillary encephalocele

A rare case of occult traumatic intramaxillary encephalocele and intraorbital encephalocele without obvious connection to exterior is described

Small intestinal bacterial overgrowth in North Indian patients with celiac disease

BACKGROUND

Occasionally celiac patients continue to experience gastro-intestinal symptoms even with a gluten free diet. In these cases, small intestinal bacterial overgrowth may be one of the causes of the lack of response. Therefore, this prospective study was planned to determine the prevalence of small intestinal bacterial overgrowth in celiac patients.

MATERIALS AND METHODS

We studied 87 confirmed cases of celiac disease from North India and 87 age and sex matched controls. Celiac disease was confirmed by positive IgA antitissue transglutaminase on ELISA. 80 g glucose hydrogen breath test (non-invasive test) was performed to establish small intestinal bacterial overgrowth. Rise of more than 10 ppm in hydrogen concentration over baseline value within two hours was considered suggestive of small intestinal bacterial overgrowth.

RESULTS

Out of 87 patients with celiac disease, 49 were male and 38 were female. The mean (+/-SD) age for male patients was 26.3 +/- 16.3 years (range 14-59 years) and for female patients was 28.4 +/- 15.6 years (range 16-58 years). Amongst the controls, 52 (59.8%) were male and 35 (40.2%) were female. The mean (+/- SD) age for male controls was 27.6 +/- 14.5 years (range 15-57 years) and for female controls was 29.3 +/- 16.5 years (range 18-59 years). Hydrogen breath test was suggestive of bacterial overgrowth in 18 of the 87 (20.7%) celiac disease patients but not in any of the apparently healthy controls.

CONCLUSION

This study indicates that a large number of celiac patients from North India suffer from bacterial overgrowth which can be accordingly treated with antibiotics.

Partially wetting thin liquid films: structure and dynamics studied with coherent x rays

We studied the surface structure of thin liquid films vapor deposited on solid substrates in a partial wetting situation by means of coherent x-ray scattering. No dynamics has been observed showing the absence of capillary waves on liquid films partially wetting a substrate. Instead an exponential form of the height-height correlation function has been found pointing toward a solidlike behavior of the thin liquid films at large length scales. The exact surface structure and degree of replication with the substrate depend on the deposition rate of the molecules.

Solvation and squeeze out of hexadecane on graphite

We have performed simultaneous force and conductivity measurement of hexadecane liquid confined between a conducting atomic force microscope tip and a graphite surface. Both the current and the force data reveal discrete solvation layering of the hexadecane near the surface. We typically observe that the current does not vary with load in a simple way as the layer closest to the surface is compressed, but increases markedly prior to the expulsion of material from the tip-sample gap. We infer that even for a nanoscale asperity there is conformation change of the confined hexadecane under the tip apex prior to squeeze out of the molecules.

Evidence for viscoelastic effects in surface capillary waves of molten polymer films

The surface dynamics of supported ultrathin polystyrene films with thickness comparable to the radius of gyration were investigated by surface sensitive x-ray photon correlation spectroscopy. We show for the first time that the conventional model of capillary waves on a viscous liquid has to be modified to include the effects of a shear modulus in order to explain both static and dynamic scattering data from ultrathin molten polymer films.

Modification of small bowel microflora in chronic alcoholics with alcoholic liver disease

The bacterial flora of the gastrointestinal tract plays an essential role in human physiology. Our aim was to study the pattern of change in bacterial microflora in the small intestines of patients with chronic alcoholic liver disease (ALD). Patients of ALD made up the test group and nonalcoholics served as controls. Duodenal (D2) biopsies were obtained by upper gastrointestinal endoscopy and processed immediately for microbiological analysis. Marked qualitative and quantitative alterations of small intestinal microflora was documented in chronic alcoholics. There was increased bacterial growth of both gram-positive cocci and gram-negative bacilli in the ALD group.

Isolation and characterization of microsomal omega-6-desaturase gene (fad2-1) from soybean

A genomic DNA sequence (fad2-1) encoding seed specific microsomal 0-6 desaturase was isolated from soybean (Glycine max. L cv. Pusa-9702). A positive genomic clone of 1852 nucleotides containing a single uninterrupted 3' end exonic region with an ORF of 1140 bp encoding a peptide of 379 amino acids, a complete 3' UTR of 206 bp and 86 bp of 5' UTR interrupted by a single intron of 420 bp was obtained on screening the sub-genomic library of soybean. Southern blots revealed at least two copies of the gene per haploid genome. Analysis of the translated product showed the presence of three histidine boxes, with the general sequence HXXXH and five probable transmembrane segments reported to be involved in substrate specificity.

Comparison of multidetector computed tomographic colonography and conventional colonoscopy for detection of colorectal polyps and cancer

BACKGROUND

Computed tomographic colonography (CTC) is a new technique for detecting colonic neoplasms. Data on the utility of this method in the Indian population are limited.

METHODS

Forty-two patients with symptoms of colonic disease underwent CTC and conventional colonoscopy (CC) within one week of each other and the findings at these two investigations were compared.

RESULTS

The entire colon could be evaluated in 38 patients on CTC and in 23 patients on CC. Of the 19 patients who had incomplete CC, 14 had occlusive colonic lesions. Of the 86 lesions detected on CC, 76 (88.4%) were correctly identified on CTC with regard to location and size. CTC was false negative for 10 lesions and false positive for 5 lesions in 3 patients. The sensitivity and specificity of CTC were 65% and 77%, respectively, for lesions 1-5 mm; 97% and 83% for 6-9 mm-sized lesions; and 100% and 100% for lesions 10 mm or larger. Extracolonic findings were seen in 24 of 42 patients (57%).

CONCLUSIONS

CTC is reliable for detecting lesions 6 mm or larger in size. It permits evaluation of the region proximal to an occlusive growth, which is often not possible with CC.

Endoscopic transpapillary nasopancreatic drainage alone to treat pancreatic ascites and pleural effusion

BACKGROUND

Pancreatic ascites and pleural effusion are uncommon sequelae of pancreatitis and are associated with significant morbidity and mortality. Endoscopic decompression of the pancreatic duct through transpapillary stent or nasopancreatic drain (NPD) has shown encouraging results but the experience is limited. The aim of the present study was to evaluate the efficacy of endoscopic transpapillary nasopancreatic drainage in patients with pancreatic ascites and pleural effusion.

METHODS

Over a period of 9 years, 10 patients (eight male) with pancreatic ascites and/or pleural effusion with pancreatic duct disruption documented on pancreatogram were studied. After informed consent, endoscopic transpapillary NPD was placed. The end-points were resolution of ascites and/or pleural effusion or need for surgery.

RESULTS

Of 10 patients (age range: 13 months-46 years), four patients had only ascites, four had only pleural effusion and two had both ascites and pleural effusion. Ascites and/or pleural effusion resolved in all the patients within 4 weeks of placement of NPD. The healing of ductal disruption was demonstrated by nasopancreatogram as early as 2 weeks and NPD could be removed without necessitating another endoscopy. No major complications related to NPD placement were noted. There was no recurrence of pancreatic ascites and/or pleural effusion at a mean follow up of 39 months.

CONCLUSIONS

Pancreatic ascites and pleural effusion can be effectively treated by endoscopic retrograde pancreatography and transpapillary NPD placement.