Detection of diarrheagenic Escherichia coli by use of melting-curve analysis and real-time multiplex PCR.

Diarrheagenic Escherichia coli strains are important causes of diarrhea in children from the developing world and are now being recognized as emerging enteropathogens in the developed world. Current methods of detection are too expensive and labor-intensive for routine detection of these organisms to be practical. We developed a real-time fluorescence-based multiplex PCR for the detection of all six of the currently recognized classes of diarrheagenic E.

Effect of lactoferrin on enteroaggregative E. coli (EAEC).

We previously demonstrated that lactoferrin inhibits adherence of enteropathogenic Escherichia coli to HEp-2 cells and decreases invasiveness of Shigella flexneri in HeLa cells by disruption of the type III secretory system (TTSS) of both enteropathogens. To determine whether these effects were specific to the TTSS, we assessed the activity of bovine lactoferrin on enteroaggregative E. coli (EAEC), enteropathogens whose virulence is not TTSS dependent.

High resolution computed tomography of the temporal bone in infants and children: a review.

Pathologic conditions involving the temporal bone in infants and children are now commonly diagnosed by computed tomography (CT). The importance of utilizing high resolution computed tomography (HRCT) with magnified, thin (1.5 mm) scans in both the axial and coronal planes is stressed in order to obtain the maximal anatomic information that is critical for proper diagnosis.

Routine chest radiographs in pediatric intensive care: a prospective study.

The clinical value of routine chest radiographs was prospectively evaluated in a pediatric intensive care unit. Physicians were asked to predict findings of clinical impact in 353 routine morning chest radiographs performed in 101 patients after examining the patients. In 81 instances (23%), the clinical impact of the chest radiographs was incorrectly predicted and significant alterations in management would have potentially been missed had the chest radiographs not been available.

Efficacy of chest radiography in pediatric intensive care.

We prospectively evaluated the efficacy and clinical usefulness of bedside chest radiography in a pediatric intensive-care unit. Seven hundred ninety-five radiographs were evaluated in 126 patients over a 10-week period. Eighty-one percent of all radiographs showed one or more cardiopulmonary abnormalities, and 25% of routine radiographs had findings that altered management of patients.

Chloroform mediated refractory state against ornithine decarboxylase induction by serial chloroform treatment.

The chloroform mediated refractory state against ornithine decarboxylase induction in male and female rat liver was further studied. One aspect of the investigation was to determine the duration of the induced refractory period while the other component focused on the extent to which the inhibitory effect was dependent upon the concentration of the first dose. When the dosing interval between the first and second dose was varied from 1 to 31 days, the magnitude of the resistance to further stimulation by chloroform only decreased gradually.

Studies on the mechanism of action of chloroform stimulation of rat hepatic ornithine decarboxylase (ODC).

We have previously reported that chloroform is a very potent stimulator of rat hepatic Ornithine Decarboxylase (ODC) activity. At that time we conducted the obligatory time course and dose response studies in male and female rats. However, in an attempt to more thoroughly understand the mechanism of this stimulation, we have examined the effects of a series of pharmacologic, physiologic and toxicologic manipulations on the chloroform response.

Effect of chloroform on hepatic and renal DNA synthesis and ornithine decarboxylase activity in mice and rats.

Chloroform administered intraperitoneally (i.p.) to male mice and rats resulted in a dose-dependent increase in hepatic ornithine decarboxylase (ODC) activity.

Induction by chloroform of two forms of ornithine decarboxylase in rat liver. Half-life of isozymes.

Ornithine decarboxylase (ODC) in rat liver was separated into two species by DEAE-Sepharose CL-6B column chromatography. The activity of both species of ODC was increased at least 20-fold by chloroform treatment of the rats. The major species, Peak A, contained 65% of the ODC activity and possessed a half-life of 11 min.

Chloroform induction of ornithine decarboxylase activity in rats.

Chloroform is a drinking water contaminant that has been demonstrated to be carcinogenic to mice and rats resulting in an increased incidence of liver and kidney tumors, respectively. The mechanism of chloroform carcinogenicity might be by tumor initiation and/or promotion. Since induction of ornithine decarboxylase (ODC) activity has been proposed as a molecular marker for tumor promoters, we have investigated the effect of chloroform on ODC activity in rats.

Comparison of enhancement of GGTase-positive foci and induction of ornithine decarboxylase in rat liver by barbiturates.

The indication of ornithine decarboxylase (ODC) by barbiturates and the ability of barbiturates to enhance neoplastic progression of chemically initiated cancer was examined in rat liver. All seven barbiturates induced ODC with barbital (7.7 fold increase) and phenobarbital (5.

Oxidative damage to the erythrocyte induced by sodium chlorite, in vitro.

The ability of sodium chlorite to react with constituents of the erythrocyte, in vitro, was examined and compared to that of nitrite. The oxidative damage resulting from chlorite is fundamentally different from that of nitrite. Nitrite is slightly more potent as an oxidant of hemoglobin, while chlorite appears to be less specific in its oxidation of cellular constituents.

Oxidative damage to the erythrocyte induced by sodium chlorite, in vivo.

Sodium chlorite in drinking water was found to produce a slight but compensated anemia in rats after exposure to up to 500 ppm for 90 days. Decreases in hemoglobin, red cell count, and packed cell volume seen after 30 days exposure had substantially recovered by 90 days of treatment. Signs of adaptation remained in that 2,3-diphosphoglyceric acid concentrations in the red cell remained elevated after 90 days exposure to 50 and 100 ppm CIO2-.