sodium-dodecyl-sulfate and Diarrhea

We developed a novel method that uses sodium dodecyl sulfate-EDTA-treated chromatography paper strips to collect unconcentrated fresh stool samples. After the paper strips were stored for 4 months at room temperature, rotavirus RNA could be successfully amplified by using reverse transcriptase PCR. The use of filter paper strips as a specimen support allows (self-)collection of stool samples by untrained persons. Diarrheal stool samples from remote areas can be stored and transported to a central diagnostic laboratory without the need for freezers or special shipping conditions. This convenient and inexpensive rotavirus sample collection system can be of use in epidemiological surveillance studies and vaccine trials.

Topics: Chromatography, Paper; Diarrhea; Edetic Acid; Feces; Humans; Reagent Strips; Reverse Transcriptase Polymerase Chain Reaction; RNA, Viral; Rotavirus; Rotavirus Infections; Sodium Dodecyl Sulfate; Specimen Handling

Six of 11 human immunodeficiency virus (HIV)-infected patients with chronic diarrhea, shedding only Candida spp. in their stools, elicited a Candida-specific secretory immunoglobulin A response. Similar responses were identified in only 1 of 10 HIV-positive patients with chronic diarrhea but without Candida spp. and in none of 10 HIV-negative subjects without diarrhea. Candida spp. may play a role in the etiology of chronic diarrhea associated with HIV infection.

Topics: AIDS-Related Opportunistic Infections; Antigens, Fungal; Blotting, Western; Candidiasis; Chronic Disease; Diarrhea; Electrophoresis, Polyacrylamide Gel; Enzyme-Linked Immunosorbent Assay; Feces; HIV Infections; Humans; Immunoglobulin A, Secretory; Intestinal Mucosa; Sodium Dodecyl Sulfate

Tryptic hydrolysis after reduction and carboxamidomethylation of staphylococcal enterotoxin B cleaved the single susceptible bond located between the 2 half-cystines of the molecule, Lys-Thr at positions 97 and 98 (Spero, L., Warren, J. R., and Metzger, J. F. (1973) J. Biol. Chem. 248, 7289-7294). The product remained as a single particle but was separated into the two constituent peptides by denaturants, and purification of the two fragments was accomplished by chromatography on CM-cellulose in 8 M urea. Antigenic activity was exhibited by the separated peptides after dialysis of urea solutions against dilute buffer, but was very labile. No emetic activity in rhesus monkeys was found for either separated peptide. The derivative behaved as two random coil peptides in 6 M guanidine hydrochloride but upon removal of guanidine refolded to a single molecular entity. Viscosity and unfolding kinetics in 1.5 M guanidine indicated physical identity of the recombined peptides with the derivative prior to treatment with guanidine. Three biological measures (serological, mitogenic, and emetic activity) were also essentially unaltered for the recombined material. Since these biological activities are dependent upon different aspects of enterotoxin structure, it is concluded that the recombined derivative was restored to its original conformation.

Topics: Animals; Diarrhea; Dose-Response Relationship, Drug; Electrophoresis, Polyacrylamide Gel; Enterotoxins; Guanidines; Immunodiffusion; Iodoacetamide; Macaca mulatta; Mice; Peptides; Rabbits; Sodium Dodecyl Sulfate; Spleen; Staphylococcus; Thymidine; Tritium; Trypsin; Vomiting