PubMed Health⌕ Search

Biomedical subjects

J W Singleton

Publications and source records attributed to J W Singleton.

At least 19 recordsLinked to original sources
PubMed1999

Preliminary evaluation of safety and activity of recombinant human interleukin 11 in patients with active Crohn's disease.

BACKGROUND & AIMS: Recombinant human interleukin 11 (rhIL-11) is a cytokine with thrombocytopoietic activity and anti-inflammatory and mucosal protective effects. The objectives of this study were to investigate the safety and tolerability of rhIL-11 in patients with Crohn's disease and to explore the effects of dose and schedule on platelet count and Crohn's disease activity. METHODS: A multicenter, double-masked, placebo-controlled, dose-escalation study of 76 patients with active Crohn's disease was performed. Patients were randomized to receive subcutaneous placebo or rhIL-11 at doses of 5, 16, or 40 microgram. kg-1. wk-1 given 2 or 5 times weekly for 3 weeks. Clinical and laboratory safety data were recorded, and disease activity was measured at each visit. RESULTS: Subcutaneous injection of rhIL-11 generally was well tolerated. Significantly greater increases in platelet counts were found among patients receiving rhIL-11 40 microgram. kg-1. wk-1 as 2 or 5 weekly doses and 16 microgram. kg-1. week-1 as 5 weekly doses compared with patients receiving placebo (P < 0.05). Patients receiving 16 microgram. kg-1. wk-1 had the highest clinical response rates, with a response seen in 42% of patients (5/12) receiving 5 weekly doses and 33% of patients (4/12) receiving 2 weekly doses, compared with 7% of patients (1/15) receiving placebo. CONCLUSIONS: Short-term treatment with rhIL-11 is well tolerated in patients with active Crohn's disease. The thrombocytopoietic effect of rhIL-11 seems to be both dose and schedule dependent and may be minimized with retained clinical benefit in Crohn's disease at 16 microgram. kg-1. wk-1 given in 2 equal doses.

Adult↗
PubMed1995

RecA.oligonucleotide filaments bind in the minor groove of double-stranded DNA.

Escherichia coli RecA protein, in the presence of ATP or its analog adenosine 5'-[gamma-thio]triphosphate, polymerizes on single-stranded DNA to form nucleoprotein filaments that can then bind to homologous sequences on duplex DNA. The three-stranded joint molecule formed as a result of this binding event is a key intermediate in general recombination. We have used affinity cleavage to examine this three-stranded joint by incorporating a single thymidine-EDTA.Fe (T*) into the oligonucleotide part of the filament. Our analysis of the cleavage patterns from the joint molecule reveals that the nucleoprotein filament binds in the minor groove of an extended Watson-Crick duplex.

Adenosine Triphosphate↗
PubMed1995

Quality-of-life results of double-blind, placebo-controlled trial of mesalamine in patients with Crohn's disease.

Seven quality-of-life parameters were assessed in a trial of mesalamine in Crohn's disease. The results with regard to efficacy and safety have been previously published. A total of 310 patients were enrolled in this double-blind, parallel trial and randomized to receive placebo, or 1, 2, or 4 g/day of mesalamine in controlled-release capsules for 16 weeks. Results revealed that mesalamine at the dose of 4 g/day resulted in significant (P < 0.03) improvements from baseline in all quality-of-life parameters. A significant (P < 0.02) linear trend between increasing doses of mesalamine and increasing response was also noted. The 1- and 2-g/day doses of mesalamine also resulted in an improvement in quality of life, however, with the exception of 2 g/day of mesalamine on the hobby and recreational activities parameter, these changes were not significantly different from placebo.

Adult↗
PubMed1993

Mesalamine capsules for the treatment of active Crohn's disease: results of a 16-week trial. Pentasa Crohn's Disease Study Group.

BACKGROUND: Mesalamine is released from sulfasalazine in the colon and benefits colonic Crohn's disease. The mesalamine used in this study releases the drug throughout the small bowel and colon. Therefore, this study was designed to detect benefit for Crohn's disease involving the small bowel alone or both the colon and small bowel. METHODS: This double-blind, randomized, multicenter prospective controlled trial compared placebo and three daily doses of mesalamine in 310 patients. The primary outcome criterion was change in the Crohn's Disease Activity Index (CDAI) from baseline to final study visit. RESULTS: Patients taking 4 g/day mesalamine experienced a decrease of 72 CDAI points compared with 21 points in the placebo group (P < 0.01). Remission occurred in 43% of the 4-g group and 18% of the placebo group. Patients with ileum-only disease showed a 93-point improvement on 4 g mesalamine, compared with a 2-point improvement in similar patients on placebo. Mesalamine in this trial was not associated with clinically significant toxicity. CONCLUSIONS: This controlled-release mesalamine preparation is safe and effective at 4 g/day as a single agent in treatment of active Crohn's disease of the ileum and colon.

Adolescent↗
PubMed1987

Clinical activity assessment in inflammatory bowel disease.

Standardized methods of making and recording clinical observations of patients with inflammatory bowel disease are needed for the conduct of controlled clinical trials and for the application of the results of such trials to clinical practice. A number of attempts to develop such methods have been made since the early 1950s, and such efforts continue at present. A universally accepted and acceptable clinical instrument to measure the disease activity of either Crohn's disease or ulcerative colitis will probably never be achieved. However, if interested clinicians can agree on a basic set of observations and how to make and record them, accurate comparisons of therapeutic outcomes across time and space will become possible. Toward this goal several groups of clinicians are currently working.

Clinical Trials as Topic↗
PubMed1987

Search for a specific marker of mucosal dysplasia in chronic ulcerative colitis.

We have tried to identify a histochemical or immunohistochemical marker that would reliably detect mucosal dysplasia in chronic ulcerative colitis. Colonic biopsy specimens were taken from patients with long-standing ulcerative colitis undergoing surveillance colonoscopy. Control tissue was obtained from the margins of colonic resections performed for neoplastic or nonneoplastic diseases. Sections of the specimens were examined by periodic acid-Schiff staining, high iron diamine Alcian blue staining for sialomucins and sulfomucins, and binding of the lectins peanut agglutinin, Ulex europeus agglutinin I, and Ricinis communis I agglutinin. Sections were reacted also with anticarcinoembryonic antigen antibodies to determine whether a nonpolar surface distribution of the antigen was a feature of dysplasia. We found that changes in colonic mucin, characterized by periodic acid-Schiff-positive mucin outside of goblet cells, an increase in binding of peanut agglutinin, and an increase in the relative amount of sialylated mucin, were associated with morphologic dysplasia. However, identical alterations were observed, albeit less commonly, in colitis without dysplasia, particularly in the presence of active inflammation. No abnormality in the surface distribution of carcinoembryonic antigen or Ricinis communis I agglutinin was observed. Thus, we did not identify a reliable corollary test to the histologic diagnosis of mucosal dysplasia in ulcerative colitis. With regard to these histochemical markers, the colonic mucosa appears to respond similarly to inflammation and neoplasia.

Carcinoembryonic Antigen↗
PubMed1984

Patients with active Crohn's disease have elevated serum antibodies to antigens of seven enteric bacterial pathogens.

A variety of bacterial pathogens including Campylobacter, Yersinia, Listeria, Brucella, and Mycobacteria have been suggested as potential etiologic agents for Crohn's disease. To assess the role of these organisms we studied responses to eight antigens in sera from patients with active Crohn's disease and healthy age- and sex-matched controls. In complement-fixation assays, the sera from the Crohn's disease patients had enhanced reactivity compared with the control sera to all seven orally ingested pathogens studied; however, only the difference in distribution of titers to Yersinia pseudotuberculosis was statistically significant (p less than 0.0025). There was no difference between the two groups in reactivity to arabinomannan, a common mycobacterial antigen. Seroreactivity to enteric pathogens not resident in the bowel flora probably represents a nonspecific sensitization to cross-reacting antigens. Lack of response to the mycobacterial antigen suggests that widespread mycobacterial disease with high bacillary load is not present in Crohn's disease.

Adolescent↗
PubMed1979

National Cooperative Crohn's Disease Study: study design and conduct of the study.

The design and execution of the National Cooperative Crohn's Disease Study are described in this paper. The Study incorporated several noteworthy features developed to meet specific demands of the disease and its therapy. A standard clinical grading system, the Crohn's Disease Activity Index (CDAI) was developed to allow uniform decentralized clinical evaluation and decision-making throughout the 5 yr of the study. All three drugs in widespread clinical use in Crohn's disease were studied both for suppressive and prophylactic efficacy and for toxicity. The study employed a scheme for double-blind evaluation of patient progress which allowed adjustment of prednisone dose according to the degree of illness and ensured continuous monitoring for serious toxicity of any study drug. Results were analyzed primarily by ranking the clinical outcome of every patient according to a uniform and detailed scheme and applying Wilcoxon nonparametric statistics. Outcome was also analyzed by life-table methods. Eleven hundred nineteen patients were entered and 604 patients were randomized at 14 study centers during the 5-yr duration of the study. Twenty patients were eliminated from analysis as not meeting diagnostic criteria for Crohn's disease, and another 15 patients were eliminated as not meeting other preestablished criteria for analysis. Nine percent of randomized patients, equally distributed in the four treatment groups, withdrew as noncompliant. Ninety percent of patients completed all or all but one protocol-specified visits, and 95% completed the final radiologic and sigmoidoscopic evaluation.

Azathioprine↗
PubMed1979

National Cooperative Crohn's Disease Study: results of drug treatment.

The response of active and quiescent Crohn's disease to prednisone, sulfasalazine, or azathioprine has been studied in 569 patients in a placebo-controlled, randomized, multicenter cooperative trial. The response of active symptomatic disease to prednisone or sulfasalazine was significantly better than to placebo. Response to azathioprine was better than to placebo, but the difference did not reach conventional levels of statistical significance. Patients with colonic involvement were especially responsive to sulfasalazine, and those with small bowel involvement were especially responsive to prednisone. Patients' drug therapy immediately before entry to the study significantly affected subsequent response. For patients with quiescent disease, none of the drugs was superior to placebo in prophylaxis against flare-up or recurrence. There is less than a 5% risk that a clinically significant prophylactic effect of any of the drug regimens was missed.

Adult↗