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C McDonnell

Publications and source records attributed to C McDonnell.

13 recordsLinked to original sources
PubMed2001

Phase I study of twice-weekly gemcitabine and concomitant external-beam radiotherapy in patients with adenocarcinoma of the pancreas.

PURPOSE: To determine the maximum tolerated dose and dose-limiting toxicity associated with twice-weekly gemcitabine and concomitant external-beam radiotherapy in patients with adenocarcinoma of the pancreas. METHODS AND MATERIALS: Twenty-one patients with biopsy-proven adenocarcinoma of the pancreas were treated with external-beam radiotherapy to a dose of 50.4 Gy in 28 fractions, concurrent with gemcitabine, infused over 30 min before irradiation on a Monday and Thursday schedule. The dose of gemcitabine was escalated in 5 cohorts of 3--6 patients each. Initial gemcitabine dose was 10 mg/m(2), with dose escalation until dose-limiting toxicity was observed. RESULTS: The maximum tolerated dose of gemcitabine was 50 mg/m(2), when given in a twice-weekly schedule with radiation. Dose-limiting toxicity was seen in 2 patients at 60 mg/m(2), and consisted of severe upper gastrointestinal bleeding approximately 1 month after completion of treatment. Six patients had radiographic evidence of response to treatment, and 5 of these underwent complete surgical resection. Three patients who underwent complete resection had been deemed to have unresectable tumors before enrollment on trial. Four patients are alive, including 2 without evidence of disease more than 1 year after resection. CONCLUSION: The combination of external-beam radiation and twice-weekly gemcitabine at a dose of 50 mg/m(2) is well tolerated and shows promising activity for the treatment of pancreatic cancer. Our data suggest a higher maximum tolerated dose and different dose-limiting toxicity than previously reported. Further investigation of this regimen is warranted.

Adenocarcinoma↗
PubMed1998

Analgesia in day case breast biopsy--the value of pre-emptive tenoxicam.

PURPOSE: Inadequate analgesia is a major problem following ambulatory surgery. In this prospective randomised study, the use of pre-operative intravenous tenoxicam (a non steroidal anti-inflammatory agent) was compared with post-incision tenoxicam for the relief of post-operative pain in 77 patients undergoing day case breast biopsy. METHODS: All patients received a standard general anaesthetic which included infiltration of the wound with bupivacalne after skin closure. Intravenous tenoxicam (20 mg) was administered as a single bolus either 30 min before surgery (37 patients) or after incision (40 patients). Pain scores (100 mm visual analog scale) were obtained at 30, 60, 120 and 240 min after surgery analgesic requirements recorded. RESULTS: Both groups of patients were similar with respect to age, weight, operative time and length of the incision. Patients receiving the tenoxicam 30 min before surgery had lower pain scores at 30 min (22 +/- 3) vs 46 +/- 3; P < 0.0001), 60 min (9 +/- 2 vs 28 +/- 3); P < 0.0001), 120 min (6 +/- 2 vs 16 +/- 3); P = 0.0002) and 240 min (3 +/- 1) vs 7 +/- 2); P = 0.02) post-operatively. They had a longer time to first analgesia (55.1 +/- 4.6 vs 29.6 +/- 2.6) min; P = 0.0004), required less meperidine (5.4 +/- 2.6 vs 18.8 +/- 3.9) mg; P = 0.007) and were more likely not to require any further analgesia during the first four hours post-operatively. CONCLUSION: Pre-operatively administered tenoxicam provides superior post-operative analgesia than tenoxicam administered after surgical incision in patients undergoing breast biopsy.

Adult↗
PubMed1994

Determination of blood flow to the transplanted kidney. A novel application of phase-contrast, cine magnetic resonance imaging.

There is at present no noninvasive method that reliably measures blood flow in the poorly functioning renal allograft. The present study was designed to evaluate phase-contrast cine magnetic resonance imaging (PC-cine-MRI) for this purpose. We recruited for study 18 patients who had received kidney transplants 13-66 months earlier from closely related living donors. As judged by the glomerular filtration rate, which was elevated for a single kidney (76 +/- 4 ml/min 1.73 m2), allograft function was excellent, permitting the assumption of unimpaired renal extraction of paminohippuric acid (PAH). Allograft blood flow was determined consecutively on the same day, first by the standard PAH clearance technique and they by the product of the velocity of protons and renal vein cross-sectional area using PC-cine-MRI. MRI determinations could not be completed because of claustrophobia in two patients and failure to image the terminus of the allograft vein another two. Comparison of blood flow in the remaining 14 subjects revealed the two techniques to be strongly related (r = 0.91, P < 0.001). On the average, the renal blood flow rate was similar by each method; 732 +/- 62 by PAH clearance and 703 +/- 69 ml/min by PC-cine-MRI, but the agreement among individuals between the two methods was only modest, with a 95% confidence interval of agreement from -214 to +254 ml/min. We conclude that PC-cine-MRI provides a fairly accurate and noninvasive method for determining the rate of blood flow in the transplanted kidney. With further refinement it should permit the role of depressed blood flow in a variety of acute and chronic forms of human allograft dysfunction to be elucidated in humans for the first time.

Glomerular Filtration Rate↗
PubMed1991

Physical overdistension converts ventricular cardiomyocytes to acquire endocrine property and regulate ventricular atrial natriuretic peptide production.

Atrial natriuretic peptide (ANP) is present in adult atria but at very low concentrations in normal adult mammalian ventricles. In the atria, the production of ANP is regulated by physical distension of the atrial wall. The same phenomenon was investigated in the ventricles of rats and men. Cardiac tissues from human ventricular aneurysm (n = 5), spontaneously hypertensive rats (n = 30), and rats that had overloaded left ventricles induced by surgery (n = 84) were studied with the methods of light microscopic immunocytochemistry, electron microscopic immunogold staining, and RNA-RNA tissue in situ hybridization. It was found that the levels of ANP gene expression, ANP immunoreactivity, and ANP-containing specific granules in the overburdened ventricles were elevated and their degrees of fluctuation were directly proportional to the force of physical distension applied to the ventricular cardiomyocytes. In rats, ANP mRNA and ANP immunoreactivity returned to the control level seven days after the ventricular overload was surgically released. The changes of ANP and its mRNA in the ventricles were related more closely to the changes of intraventricular pressure than to cardiocytic hypertrophy. In addition, ANP immunoreactivity was demonstrated in Purkinje cells and periarteriolar cardiomyocytes in the ventricles of normotensive rats. In conclusion, physical overstretch of the ventricle wall is likely to be the triggering factor affecting ventricular cardiomyocytes to acquire endocrine property, and also to regulate the production of ventricular ANP, thereby contributing to the control of the blood volume and the blood pressure.

Animals↗
PubMed1990

Acute and custodial care among impaired aged.

The authors surveyed a community-based population of 628 persons who were 65 and over and who lived either in a rural Maryland county or in Baltimore. For each subject, the number of different medical problems, the subject's capacity to perform physical tasks, and the ability to function were assessed. The number and type of medical problems tended to be the best predictors of whether or not hospital or physician's office care were used, and of the volume of physician's office visits for subjects who sought outpatient care. The subject's ability to function was the best predictor of whether or not the subject used a paid home aide and the volume of family caregiving. Implications for research on association between need and use of long-term care are discussed.

Activities of Daily Living↗
PubMed1982

Rapid processing of urine specimens by urine screening and the AutoMicrobic system.

A total of 1,500 clean-voided urine specimens were analyzed for the presence of bacteria by urine screening with the Autobac 1 system. The specimens found positive by this method were further processed on the same day for identification and for antimicrobial susceptibility testing on the AutoMicrobic system with the Enterobacteriaceae-plus Card and the General Susceptibility Card, respectively. The inocula for these tests were prepared from the centrifuged and washed growth in the eugonic broth aspirated from the Autobac cuvette chambers. Of 1,500 specimens that were analyzed, 183 contained single isolates of gram-negative bacilli. The results of these rapid procedures were compared with results for the same organisms isolated from urine specimens cultured by the conventional method. The data showed 92.3% agreement for identification and a correlation of 93.6% for antibiotic susceptibility between the two procedures. It is concluded that gram-negative bacilli can be rapidly identified and tested for antimicrobial susceptibility with a high degree of accuracy from the centrifuged eugonic broth after urine screening. These findings also suggest that the AutoMicrobic system provides a rapid and convenient method for same-day processing of positive urine cultures when combined with the urine screening procedure.

Anti-Bacterial Agents↗