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K Caswell

Publications and source records attributed to K Caswell.

6 recordsLinked to original sources
PubMed1992

Advantages of achiral h.p.l.c. as a preparative step for chiral analysis in biological samples and its use in toxicokinetic studies.

1. Achiral reverse-phase h.p.l.c. with semi-automated post-column fraction collection and solid-phase sample reconcentration, has been applied as the purification procedure during the enantiomeric quantification of two widely differing experimental drugs; an HMG-CoA reductase inhibitor (I) and an alpha 2-adrenoceptor antagonist (II). 2. The robust and specific achiral methodologies were available prior to the need for chiral analyses and recovery of drug from the fractions provided clean samples from a variety of biological matrices, without the need to develop compatible achiral/chiral mobile phases. 3. Compared with direct chiral chromatography of plasma extracts, this approach decreased the potential for metabolites and endogenous components to interfere or impair the performance of the chiral stationary phase. 4. The availability of quantitative data from achiral analysis of samples negated the need for internal standardization of the chiral analyses, helped confirm assay specificity and provided potential to determine enantiomeric ratios where only one isomer could be accurately measured. 5. Routine enantiomeric analyses were successfully carried out on samples taken from animals dosed orally with the racemic drugs, providing important data on the possible levels of exposure to individual enantiomers during toxicity testing.

Animals↗
PubMed1983

Absence of cardiac arrhythmias during a very-low-calorie diet with high biological quality protein.

Fourteen women who were at least 50 lb (22.7 kg) overweight entered the 15 week study which included 4 weeks of 1200 cal (5028 J) balanced diet followed by 7 weeks on a very-low-calorie diet (VLCD) and 4 weeks of refeeding. During the VLCD high biological quality protein (poultry, fish) and recommended supplements of vitamins, minerals and water were used. With the exception of week 5 and 14, 25-h Holter monitorings were done weekly. During the initial 4 weeks, 2 patients showed disturbances of cardiac rhythm and were discharged from the study. Twelve patients completed the trial without any clinically significant changes in cardiac rhythm. The 12 lead ECGs remained normal in all patients throughout the study. The average weight loss was 46 lb (20.9 kg) and the whole program was well tolerated. It is concluded that seven weeks of VLCD with high biological quality protein and recommended supplements appears to be a safe method for weight reduction for severely obese patients.

Adult↗
PubMed1977

Open-heart surgery.

A randomized prospective study of the relative effectiveness of broad-spectrum versus specific antistaphylococcal antibiotic prophylaxis in open-heart surgery was done between May 1972 and June 1973. All patients undergoing open-heart surgery were assigned randomly (by hospital number) to receive either methicillin (M) or cephalothin (C) beginning the night before operation. There were 132 patients in the C group and 129 in the M group. There were no statistically significant differences in age or duration of hospitalization, cardiopulmonary bypass, urinary tract drainage, or postoperative fever. There was a significant difference in the ratio of male to total patients (0.67 C, 0.52 M, P less than .02) and duration of operation in hours (4.27 C, 3.87 M, P less than .02). A statistically significant higher rate of urinary tract infection (3 C, 22 M, P less than .05), pneumonia (0 C, 9 M, P less than .01), and episodes of sepsis and prosthetic endo carditis (0 C, 11 M, P less than .001) was found in the methicillin group. The incidence of wound infections and positive cultures from blood obtained immediately after termination of cardiopulmonary bypass was not significantly different. Cephalothin replaced methicillin as the routine antibiotic prophylaxis for open-heart surgery at our institution.

Adult↗
PubMed1977

Antibiotic prophylaxis for open-heart surgery.

A randomized, prospective study of the relative effectiveness of broad-spectrum versus specific antistaphylococal antibiotic prophylaxis in patients having open-heart surgery was performed between May, 1972, and June, 1973. All patients undergoing open-heart surgery was assigned randomly (by hospital number) to receive either methicillin or cephalothin beginning the night before operation. There were 132 patients in the cephalothin group and 129 in the methicillin group. There was no statistically significant differences in age or duration of hospitalization, cardiopulmonary bypass, urinary tract drainage, or postoperative fever. There was a significant difference in the ratio of male to total patients (cephalothin group, 0.67; methicillin group, 0.52; p less than 0.02) and duration of operation (cephalothin group, 4.27 hours; methicillin group, 3.87 hours; p less than 0.05). The methicillin group had a statistically significant higher rate of urinary tract infection (cephalothin group, 3 cases; emthicillin group, 22 cases, p less than 0.05), pneumonia (cephalothin group, no cases; methicillin group, 9 cases; p less than 0.01), and episodes of sepsis and prosthetic valve endocarditis (cephalothin group, no cases; methicillin group, 11 cases, p less than 0.001). The incidence of wound infections and positive blood cultures from blood obtained immediately after termination of cardiopulmonary bypass was not significantly different between the two groups. Cephalothin has replaced methicillin as the routine prophylaxis for open-heart surgery at our institution.

Bacterial Infections↗
PubMedDate not supplied

Use of plaster casts in the management of diabetic neuropathic foot ulcers.

Neuropathic foot ulceration is a major medical and economic problem among diabetic patients, and the traditional treatment involves bed rest with complete freedom from weight-bearing. We have investigated the use of walking plaster casts in the management of seven diabetic patients with long-standing, chronic plantar ulcers. Although all ulcers healed in a median time of 6 wk, this therapy was not without side effects, which are described in detail. We conclude that casting is a useful therapy for neuropathic ulcers, although several clinic visits, including cast removal and foot inspection, are necessary to avoid potential side effects caused by the casting of insensitive feet.

Adult↗