L-isoleucine-supplemented Oral Rehydration Solution in the Treatment of Acute Diarrhoea in Children: A Randomized Controlled Trial.

Antimicrobial peptides represent an important component of the innate immune defenses of living organisms, including humans. They are broad-spectrum surface-acting agents secreted by the epithelial cells of the body in response to infection. Recently, L-isoleucine and its analogues have been found to induce antimicrobial peptides. The objectives of the study were to examine if addition of L-isoleucine to oral rehydration salts (ORS) solution would reduce stool output and/or duration of acute diarrhoea in children and induce antimicrobial peptides in intestine. This double-blind randomized controlled trial was conducted at the Dhaka Hospital of ICDDR,B. Fifty male children, aged 6-36 months, with acute diarrhoea and some dehydration, attending the hospital, were included in the study. Twenty-five children received L-isoleucine (2 g/L)-added ORS (study), and 25 received ORS without L-isoleucine (control). Stool weight, ORS intake, and duration of diarrhoea were the primary outcomes. There was a trend in reduction in mean±standard deviation (SD) daily stool output (g) of children in the L-isoleucine group from day 2 but it was significant on day 3 (388±261 vs 653±446; the difference between mean [95% confidence interval (CI) (-)265 (-509, -20); p=0.035]. Although the cumulative stool output from day 1 to day 3 reduced by 26% in the isoleucine group, it was not significant. Also, there was a trend in reduction in the mean±SD intake of ORS solution (mL) in the L-isoleucine group but it was significant only on day 1 (410±169 vs 564±301), the difference between mean (95% CI) (-)154 (-288, -18); p=0.04. The duration (hours) of diarrhoea was similar in both the groups. A gradual increase in stool concentrations of ß-defensin 2 and 3 was noted but they were not significantly different between the groups. L-isoleucine-supplemented ORS might be beneficial in reducing stool output and ORS intake in children with acute watery diarrhoea. A further study is warranted to substantiate the therapeutic effect of L-isoleucine.

Isolation and characterization of Helicobacter pylori strains from peptic ulcer patients in Dhaka, Bangladesh.

To study the association of Helicobacter pylori with peptic ulcer and the associated histopathological changes, to characterize the isolated strains in terms of their protein profile, 83 peptic ulcer cases were studied. A high association of H pylori with peptic ulcer (duodenal ulcer 77%, gastric ulcer 75%) and gastritis (74%) was observed. Age and smoking did not have any relationship with H pylori infection. The infection was predominantly associated with the 'quiescent' form of chronic gastritis. Comparative sodium dodecyl sulfate polyacrylamide gel electrophoresis of whole cell extracts of the local isolates and a reference strain from Australia showed a general homogeneity between the strains with obvious interstrain differences. However, the difference between the local isolates and the reference strain was more marked. Significant association of H. pylori with peptic ulcer along with strain variations were observed.

Antigen profile of Helicobacter pylori strains isolated from peptic ulcer patients in Dhaka, Bangladesh.

The whole-cell-extract and the acid-extract preparations of Helicobacter pylori strains isolated from peptic ulcer patients and the NCTC 11638 control strain were studied to compare their antigen profiles. Besides, the anti-H. pylori-antibody profile in serum from H. pylori-infected peptic ulcer patients were also studied to define the antigen stimulating specific anti-H. pylori-antibody response in the infected patients. The whole-cell extract (WCE) and the acid-extract (AE) preparations showed a general antigenic homogeneity among the H. pylori strains isolated from the patients and the NCTC 11638 control strain. A humoral immune response against the infecting organism was observed and three antigenic bands of approximate molecular masses of 61 kDa, 58 kDa and 24 kDa were recognized by all the tested sera. Those bands were found to be unique for H. pylori and did not show any cross reaction with the Campylobacter jejuni antigenic bands. This makes them a candidate for the specific antigens required to develop a specific serological diagnostic test. Further purification and characterization of the protein bands may be carried out to define their probable diagnostic or immuno-pathogenic role.

Occurrence of a large plasmid in a strain of Plesiomonas shigelloides with cross-reactivity against Shigella sonnei.

The plasmid profile of P. shigelloides SVC 01, strain with cross-reactivity with Sh. sonnei, (obtained from Dr Alf Lindberg, Stockholm University, Sweden), was assayed and compared with other local isolates of Plesiomonas spp. and also with Sh. sonnei. Diversity in occurrence of plasmids among different strains of P. shigelloides were observed. Further, the SVC 01 strain and Sh. sonnei differ in their plasmid profile.