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J J Mathewson

Publications and source records attributed to J J Mathewson.

At least 55 records · Page 3Linked to original sources
PubMed1990

A randomized, open-label comparison of nonprescription loperamide and attapulgite in the symptomatic treatment of acute diarrhea.

The efficacy of nonprescription doses of loperamide hydrochloride (Imodium A-D) was compared with nonfibrous activated attapulgite (Diasorb) in a randomized, parallel, open-label study of adult patients with acute diarrhea. The results of the study showed loperamide to be more effective than attapulgite in the control of diarrhea. Loperamide significantly reduced stool frequency compared with attapulgite, particularly within the first 12-hour period following the start of therapy, and significantly shortened the mean time to last unformed stool (loperamide, 14.2 hours, versus attapulgite, 19.5 hours). Subjective evaluations of severity of enteric symptoms, overall relief following treatment, and overall relief after 48 hours of treatment were equivalent for both drugs. Both treatments were well tolerated, and there was no difference between treatments with respect to the proportion of patients reporting adverse experiences.

Acute Disease↗
PubMed1990

Treatment of traveler's diarrhea with sulfamethoxazole and trimethoprim and loperamide.

In a randomized, double-blind, placebo-controlled trial, 227 US adults with acute diarrhea in Mexico received a single dose of sulfamethoxazole and trimethoprim (1600/320 mg) or 3 days of therapy with loperamide hydrochloride (4-mg loading dose, then 2 mg orally after each loose stool), sulfamethoxazole-trimethoprim (800/160 mg orally twice daily), or the combination of both. Subjects treated with the combination had the shortest average duration of diarrhea compared with the placebo group (1 hour vs 59 hours), took the least amount of loperamide after the loading dose (3.8 mg), and had the shortest duration of diarrhea associated with fecal leukocytes or blood-tinged stools (4.5 hours). A single dose of sulfamethoxazole-trimethoprim was also efficacious (28 vs 59 hours), but loperamide alone was significantly effective only when treatment failures were treated with antibiotics (33 vs 58 hours). The combination of sulfamethoxazole-trimethoprim plus loperamide can be highly recommended for the treatment of most patients with traveler's diarrhea.

Adult↗
PubMed1990

Evaluation of a selective enrichment technique for the isolation of Campylobacter pylori.

To cultivate Campylobacter pylori from contaminated biopsy specimens, Brucella broth was supplemented with 10% fetal calf serum, 1% Vitox, 1000 units/ml polymyxin B sulfate, 10 micrograms/ml vancomycin, and 2 micrograms/ml amphotericin B. Pseudomonas aeruginosa, Candida albicans, and Enterococcus fecalis were cocultivated with C. pylori. All four strains of C. pylori were recoverable at 24 h. When 21 C. pylori strains were studied in pure culture, 86% grew in the selective enrichment medium. In a clinical study, the selective enrichment technique resulted in isolation of C. pylori from 50% of patient samples, compared with isolation from only 36% of samples with agar cultivation. The selective enrichment technique may be more sensitive than techniques currently employed to isolate C. pylori from gastric tissue.

Bacteriological Techniques↗
PubMed1990

Multiple-challenge study of host susceptibility to Norwalk gastroenteritis in US adults.

In a multiple-challenge study of US adult volunteers with low or high levels of serum antibody to Norwalk virus, Norwalk inoculum 8FIIa was administered to 42 subjects, 22 were challenged 6 months later, and 19 received a third challenge after 6 more months. All 12 with high (greater than or equal to 1:200) but only 19 of 30 with low (less than 1:100) prechallenge titers experienced illness or a fourfold increase in titer after the first challenge (P less than .025). Only 4 of those challenged twice became ill; all had low initial titers but 3 had high titers before the second challenge. None became ill after a third challenge. Nine (47%) had high titers immediately before the third challenge; 3 had low titers before and after each challenge and remained asymptomatic. Thus, preexisting serum antibody to Norwalk virus does not seem to be associated with protective immunity, but antibody levels become associated with protection after repetitive exposure. Short-term resistance lasts greater than or equal to 6 months after challenge, and a small percentage of resistant individuals maintain low antibody titers even after multiple challenges.

Antibodies, Viral↗
PubMed1990

Occurrence of Norwalk virus infections among adults in Mexico.

Norwalk virus infection was sought in 48 US, 49 Puerto Rican, and 27 Mexican adults attending medical school in Guadalajara (Mexico) who were enrolled in a 2-year longitudinal study. Serum specimens were collected quarterly and as acute- and convalescent-phase samples around episodes of gastroenteritis. The reciprocal Norwalk virus geometric mean titer (GMT) for Puerto Rican students (567) was significantly higher than that of the US students overall (294; P less than .001) and for four of nine quarterly periods. The reciprocal Norwalk GMT for Mexican students (748) was also significantly higher than that of the US students overall (P less than .001) and for seven of nine quarterly periods. The average percentage of students per year with seroconversions was 30%. The rate of Norwalk virus infection averaged 0.36 episodes per student-year. Symptoms of gastroenteritis associated with seroconversion occurred in 45% of students. Preexisting serum antibody did not protect against subsequent Norwalk virus infection in these subjects. All student groups had similar rates of infection and symptomatic gastroenteritis.

Adult↗
PubMed1990

Emergence of resistant fecal Escherichia coli in travelers not taking prophylactic antimicrobial agents.

Fecal specimens from individuals traveling to Mexico were examined before, during, and after travel for the presence of Escherichia coli resistant to ampicillin, chloramphenicol, gentamicin, kanamycin, streptomycin, sulfonamides, trimethoprim (TMP), and TMP-sulfamethoxazole (TMP-SMX). None of these individuals took prophylactic antibiotics, although 4 of 13 took short courses of an antimicrobial agent for therapy of traveler's diarrhea. With an average of 9.3 E. coli per sample, resistance to all agents tested except gentamicin was shown to increase during the time in Mexico (P less than 0.001 to P less than 0.05). For example, no TMP-resistant (Tmpr) E. coli isolates were found by this method before travel, whereas 57% of the individuals had Tmpr and Tmpr-Smxr E. coli by the final week in Mexico. This increase in resistance occurred regardless of whether an individual took a short course of antimicrobial therapy. This study shows that travel itself, even without the use of prophylactic or therapeutic antimicrobial agents, is associated with the acquisition of resistant E. coli. Travel to developing nations may rival other sources of resistant organisms.

Anti-Bacterial Agents↗
PubMed1990

Comparison of two assay methods for patterns of adherence to HEp-2 cells of Escherichia coli from patients with diarrhea.

To determine whether methodological differences in the HEp-2 adherence assay could explain conflicting results of field studies, 244 strains of Escherichia coli from Mexican children with diarrhea were tested for patterns of adherence by the method used at the Center for Vaccine Development, University of Maryland (CVD), and at the Center for Infectious Diseases, University of Texas Medical School and School of Public Health (UTH). The CVD assay differentiated three phenotypes of adherent E. coli, including localized, diffuse, or aggregative adherence (LA, DA, or AA, respectively). There was agreement on pattern of adherence in 241 of the 244 strains (98.8%) tested by the CVD method in both Baltimore and Houston, and AA+ was the most common phenotype (28.5% of isolates). Among these isolates, the UTH assay detected only two adherent phenotypes (LA and DA), since it did not distinguish the AA pattern. The LA+ strains detected by each assay were compared for positivity with the enteropathogenic E. coli adherence factor (EAF) gene probe. Of the 16 strains LA+ by the CVD method, 100% were EAF+; in contrast, only 11 of 22 strains LA+ by the UTH method were EAF+ (P = 0.00074). These results help explain why in pediatric field studies in Mexico where isolates were tested by the UTH method (J. J. Mathewson, R. A. Oberhelman, H. L. Dupont, F. J. de la Cabada, and E. V. Garibay, J. Clin. Microbiol. 25:1917-1919, 1987) LA+ strains often did not belong to enteropathogenic E. coli O serogroups and why the AA pattern was not observed; the opposite was found in studies of pediatric diarrhea in Chile in which the CVD assay was used (M. M. Levine, V. Prado, R. M. Robins-Browne, H. Lior, J. B. Kaper, S. Moseley, K. Gicquelais, J. P. Nataro, P. Vial, and B. Tall, J. Infect. Dis. 158:224-228, 1988). Since it appears that both assays identify E. coli strains associated with diarrheal illness, the genetic relationships among these strains should be examined in future studies.

Bacterial Adhesion↗
PubMed1989

Escherichia coli O114:nonmotile as a pathogen in an outbreak of severe diarrhea associated with a day care center.

Five infants from a day care center developed severe diarrhea associated with enteropathogenic Escherichia coli O114:nonmotile (EPEC O114:NM) and required hospitalization. Five additional cases of diarrhea associated with EPEC O114:NM subsequently occurred, four in hospital contacts of the patients and one in a household contact. Biochemically, all EPEC O114:NM isolates were sorbitol nonfermenters. All isolates produced low concentrations of cytotoxin with a mean of 10(1.23) CD50/mg of protein. Cytotoxin was not neutralized with antibody to Shiga-like toxin I or II. Heat-labile and heat-stable enterotoxins were not present by gene probe analysis. Stool isolates from 9 of 10 hospitalized infants were positive for EPEC adherence factor by colony blot DNA probe analysis. The severity of the disease, sorbitol nonfermentation, and presence of enteroadherence are unusual features of this organism.

Child Day Care Centers↗
PubMed1989

A comparative study of furazolidone and placebo in addition to oral rehydration in the treatment of acute infantile diarrhea.

Between July and October 1987 an outpatient study of 191 children with acute diarrhea was undertaken in two rural communities in Mexico. Through a double-blind randomization we compared the efficacy of a combination therapy of furazolidone, 7.5 mg/kg/day, plus standard oral rehydration therapy (ORT) (96 patients) versus a placebo plus ORT (95 patients), each given for 5 days. Diarrheal stool samples were collected from all patients before therapy. By means of a two-vial transport media system the samples were sent to a university laboratory and examined for viral, bacterial, and parasitic organisms. The most commonly isolated organisms were enterotoxigenic Escherichia coli (13%) and Giardia lamblia (13%). Patients who received furazolidone plus ORT showed a greater reduction in duration of diarrhea when compared with those receiving placebo plus ORT (63.4 h versus 71.44 h). There was also a trend toward shorter duration of diarrhea in patients with Giardia who were treated with furazolidone/ORT compared with Giardia patients in the placebo/ORT group. When fecal leukocytes were present in the stool, the furazolidone/ORT-treated patients had a significantly higher percentage of clinical cures (79% versus 54%, p = 0.03) and an overall shorter duration of diarrhea (62.0 h versus 80.6 h, p = 0.055) at the end of 5 days of therapy than did the placebo/ORT-treated group.

Diarrhea, Infantile↗
PubMed1988

Travelers' diarrhea in West Africa and Mexico: fecal transport systems and liquid bismuth subsalicylate for self-therapy.

The goals of this study were threefold: to compare the etiology of travelers' diarrhea in West Africa and Mexico, to evaluate two fecal transport systems for the recovery of enteropathogens, and to verify the efficacy of liquid bismuth subsalicylate (BSS) in different locations and under different entrance criteria for disease severity. The study populations consisted of 133 European tourists in West Africa and 112 American students in Mexico who had suffered from travelers' diarrhea. In 60% and 38% of the stool samples at the two study sites, similar proportions of enteropathogens were detected. A two-vial system consisting of Enteric Plus medium and polyvinyl alcohol fixative was slightly superior for identifying enteric pathogens than was a three-vial system with buffered glycerol saline, Cary-Blair medium with campylobacter antibodies, and polyvinyl alcohol fixative. In a parallel, double-blind, randomized trial, BSS significantly shortened disease duration at both study sites.

Aeromonas↗
PubMed1988

Test-of-cure stool cultures for traveler's diarrhea.

Whether enteropathogens were eradicated or persisted in test-of-cure stool cultures from 251 patients with traveler's diarrhea, the durations of diarrhea were similar within the antimicrobial agent-treated (32 versus 33 h) and placebo-treated (82 versus 96 h) groups. Routine test-of-cure stool cultures can be useful for evaluating treatment failures and for assessing asymptomatic carriage of enteropathogens after treatment, but they are not mandated in the design of placebo-controlled antimicrobial treatment trials in traveler's diarrhea when the focus of the trial is clinical efficacy.

Carrier State↗
PubMed1988

Heat susceptibility of bacterial enteropathogens. Implications for the prevention of travelers' diarrhea.

The heat susceptibility of four bacterial enteropathogens in foods and water was studied to develop effective recommendations for travelers to regions where diarrheal diseases are important health problems. All enteropathogens tested survived well in foods stored at refrigerator temperature (4 degrees C), room temperature (25 degrees C), and 50 degrees C, which is too hot to touch. Tap water had to be heated above 65 degrees C to reliably kill all bacterial enteropathogens. At 13 of the 14 tourist-oriented hotels in four countries, water from the hot water tap did not reach temperatures of 65 degrees C. The implications of this study are that food and water that are too hot to touch may still be contaminated with bacterial enteropathogens. Travelers should be advised that food, water, or beverages are safe only if they have been brought to boiling or near-boiling temperatures prior to consumption.

Bacterial Physiological Phenomena↗
PubMed1987

Enteroadherent Escherichia coli as a cause of diarrhea among children in Mexico.

Enteropathogenic Escherichia coli (EPEC) often exhibits localized adherence or diffuse adherence to HEp-2 cells. We recently provided evidence that HEp-2 cell-adherent or enteroadherent E. coli (EAEC) not belonging to EPEC serogroups was the cause of diarrhea among U.S. travelers to Mexico. In the present study, we looked for EAEC and EPEC in stool specimens from 154 children with acute diarrhea and 137 well children seen at several outpatient clinics in Guadalajara, Mexico. EAEC showing localized adherence (EAEC-L) was isolated from 13.0% of the patients and 0.7% of the controls (P less than 0.0001). EAEC showing diffuse adherence (EAEC-D) was recovered from 20.8% of the patients and 7.3% of the controls (P less than 0.001). EPEC was isolated from 4.5 and 6.7% of the patients and controls, respectively. Among all enteropathogens, only enterotoxigenic E. coli occurred as commonly (21.4%) as EAEC-D and EAEC-L did in children with diarrhea. Of the EAEC-L strains isolated from children with diarrhea, 20% belonged to recognized EPEC serogroups, and 3.1% of EAEC-D strains belonged to recognized EPEC serogroups. This study suggests that EAEC may be an important pediatric enteropathogen in Mexican children with diarrhea and further supports the observation that adherence to HEp-2 cells may be a marker of virulence independent of EPEC serogroup among E. coli strains.

Bacterial Adhesion↗
PubMed1986

Western blot analysis of intestinal secretory immunoglobulin A response to Campylobacter jejuni antigens in patients with naturally acquired Campylobacter enteritis.

Secretory immunoglobulin A (sIgA) response at the intestinal mucosa is a primary defense against enteric infections. We sought to determine which antigens of Campylobacter jejuni outer membranes elicited sIgA responses in 8 patients with naturally acquired Campylobacter enteritis using Western blot analysis of fecal extracts. Naturally acquired Campylobacter infection elicited an sIgA response in 7 of 8 patients. Of these 7 patients, 5 had Campylobacter-specific sIgA titers of 1:16 and two had titers of 1:64. The C. jejuni antigens eliciting sIgA production varied, but 5 of 8 patients exhibited reactions to a 63-kilodalton flagellar antigen, and 7 of 8 patients had a reaction with a 58- and a 44-kilodalton antigen of C. jejuni and Campylobacter coli. Reaction with a 14.5- and a 97-kilodalton antigen was observed with the only stool that contained gross blood and mucus. Reactions with Campylobacter antigens were not detected in the fecal extracts of 5 healthy individuals. Identification of the antigens of C. jejuni that elicit an sIgA response may help us to better understand the immunology of Campylobacter enteritis and to identify antigens that are important in vaccine development.

Antigens, Bacterial↗