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S L Morgan

Publications and source records attributed to S L Morgan.

At least 73 records · Page 4Linked to original sources
PubMed1989

Creation of a regional medical-nutrition education network.

The Southeastern Regional Medical-Nutrition Education Network (SER-MEN) was developed to coordinate and improve nutrition education in a consortium of the medical schools in Alabama, Florida, Georgia, and South Carolina. SERMEN's central office is at the Medical College of Georgia with the testing office at the University of Alabama at Birmingham. Students, faculty, and consultants in nutrition, education, and computer networking work together on projects on each campus that are coordinated and planned through semiannual meetings. A standardized examination was developed with the Nutrition Test-Item Bank to assess nutrition knowledge at various years of medical students from network schools. Each SERMEN school is connected to a microcomputer system at the central office that provides access to a data base of nutrition education and resources on each campus for developing curricula and syllabi. Funding has been provided by societies, foundations, and government agencies.

Computer Communication Networks↗
PubMed1989

Families' experiences in psychiatric emergencies.

Sixty families from three self-help, psychoeducational groups in western New York State were interviewed about their experiences during recent psychiatric emergencies involving their mentally ill relatives. Twenty-six hospital-based emergency mental health service providers were compared with the families on key attitudes toward emergency services. Families reported that emergencies were complicated and traumatic and that they involved contacts with numerous agencies, sometimes over several months. Satisfaction with the emergency service system was generally low among both families and hospital service providers. Service providers were less likely than families to believe that families' assessments of their ill relatives' need for treatment were credible. The author suggests that apparently "crazy" behavior of families may make sense in the context of serious patient pathology and a general lack of emergency assistance. Much effort is needed to develop coordinated emergency mental health treatment that is sensitive to families' needs.

Adaptation, Psychological↗
PubMed1988

A comparison of nutrition knowledge of freshmen and senior medical students: a collaborative study of southeastern medical schools.

It has been documented previously that nutrition knowledge of senior medial students at ten southeastern medical schools varies and is positively correlated with student assessment of the quantity and quality of nutrition education. To determine whether the differences in knowledge are related to the medical educational experience or are simply a reflection of differences in the students' knowledge on entry to medical school, the same examination was administered to entering freshmen at eight of the medical schools. The knowledge scores of freshmen were remarkably homogeneous from school to school (53 +/- 1%, range 51-55%), and nutrition knowledge was significantly higher for seniors than for the freshmen at all schools (mean 69 vs 53%, p less than 0.0001). On the basis of responses to survey items on the examination, the freshman medical students were more inclined than senior students to take a nutrition elective (62 vs 34%, p less than 0.0001), and more freshman rated nutrition as being important to their careers (74 vs 59%, p less than 0.05). These data indicate that 1) entering freshman medical students at the different schools studied have comparable levels of nutrition knowledge and are receptive to nutrition education, and 2) differences in medical training programs most likely explain the previously documented variability in nutrition knowledge of graduating medical students. These findings have important implications for professionals planning curricula for medical-nutrition education.

Education, Medical, Undergraduate↗
PubMed1988

Cross-sectional study of nutrition knowledge and attitudes of medical students at three points in their medical training at 11 southeastern medical schools.

Eleven southeastern medical schools cooperated to evaluate nutrition knowledge and attitudes of medical students. This study complements previous reports of an examination of entering freshmen and seniors. Average knowledge scores for 165 students tested after basic sciences (preclinical) training in this study were 67 +/- 7% compared with 53 +/- 6% for freshmen and 69 +/- 8% for seniors. The upperclassmen's scores were higher than the freshmen's (p less than 0.001) and varied with the amount of required nutrition teaching. Only 13% of preclinical students perceived nutrition as important to their careers compared with 74% of entering and 59% of graduating students, suggesting that preclinical teaching reduces their sense of relevance of nutrition to medicine. These findings suggest that nutrition knowledge can be increased through preclinical coursework and that the knowledge level can be maintained through the clinical years. However, the positive attitude of freshmen toward nutrition is lost after preclinical training and is only partially regained after the clinical years.

Attitude of Health Personnel↗
PubMed1988

Cefazolin versus cefamandole for prophylaxis during total joint arthroplasty.

A prospective, randomized, double-blind comparison of cefazolin versus cefamandole was carried out to evaluate safety and efficacy and to determine bone and serum antibiotic concentrations in patients undergoing total joint arthroplasty. Dosages were 1 g of cefazolin before surgery followed by 500 mg every eight hours for six doses, versus 2 g of cefamandole before surgery followed by 1 g every eight hours for six doses. Intraoperative doses were given during prolonged procedures. No significant adverse drug reactions were clearly attributable to either drug. Among 48 patients receiving cefazolin there was one postoperative wound infection and one distant site infection. Among 49 patients receiving cefamandole, there were two postoperative wound infections and two distant site infections. No deep wound infections occurred in either group during at least 48 months of follow-up study. In hip specimens removed at surgery, the mean antibiotic concentrations were 1.6 +/- 1.4 micrograms/g for cefazolin recipients, compared with 5.7 +/- 5.9 micrograms/g for cefamandole recipients (p less than .001). In knee specimens, the mean antibiotic concentrations were 0.64 +/- 0.57 microgram/g for cefazolin recipients compared to 3.8 +/- 3.4 micrograms/g for cefamandole recipients (p = .004). Cefazolin given at one-half the dose of cefamandole appeared to be equally safe and effective but resulted in lower bone concentrations of antibiotic.

Aged↗
PubMed1987

Solid-phase extraction and high-performance liquid chromatographic method for chlorpromazine and thirteen metabolites.

A rapid and reliable procedure, based on a C8 bonded phase extraction and reversed-phase isocratic high-performance liquid chromatographic separation with internal standard quantitation, has been developed for the determination of the antipsychotic drug chlorpromazine and thirteen common metabolites. The method allows quantitation of these analytes at the ng/ml concentration range in human plasma. An evaluation of recovery, detection limits, and reproducibility is presented along with application of the method to patient samples.

Biotransformation↗
PubMed1987

High-performance liquid chromatographic analysis of vancomycin in plasma, bone, atrial appendage tissue and pericardial fluid.

Solid-phase extraction coupled with reversed-phase high-performance liquid chromatography and UV detection was employed for the analysis of the antibiotic vancomycin in patient plasma, bone, atrial appendage, and pericardial fluid. Vancomycin was quantitated in samples from patients undergoing cardiac surgery. Calibrations were linear in the range 3-100 micrograms/ml vancomycin; the lower limit of detection was approximately 3 micrograms/ml in fluids with an absolute limit of detection in bone samples of 0.75 microgram per injection.

Bone and Bones↗
PubMed1987

Folate status of rheumatoid arthritis patients receiving long-term, low-dose methotrexate therapy.

The folate status of 29 healthy control subjects, 16 rheumatoid arthritis (RA) patients taking methotrexate (MTX), and 20 RA patients who were not being treated with MTX was estimated by an assay of the folate-dependent enzymatic synthesis of serine from formate and glycine, which is termed the C1 index. Analysis of variance demonstrated that the specific activity of the enzyme system in lymphocytes was significantly lower in the MTX-treated group, with an activity approximately one-half that of the control and the non-MTX-treated groups. Since the C1 index is one of the first biochemical parameters found to be different between MTX-treated and non-MTX-treated groups, alterations in folate-mediated amino acid metabolism may be involved in the mechanism of response to MTX therapy. Use of the C1 index may assist in the development of protocols which preserve the efficacy of MTX therapy while minimizing toxicity.

Adult↗
PubMed1987

Carbohydrate profiling of bacteria by gas chromatography-mass spectrometry: chemical derivatization and analytical pyrolysis.

Carbohydrate profiling by gas chromatography-mass spectrometry is a powerful tool for the identification and detection of bacteria. Its increasing applicability in the microbiology laboratory is illustrated by three examples. In the first, differentiation of legionellae by their sugar composition was determined with alditol acetate derivatization followed by selected- ion monitoring. In the second example, a carbohydrate pyrolysis product from Streptococcus agalactiae was used to differentiate group B streptococci from other Lancefield groups after direct sampling from culture plates. The third example employed the carbohydrates rhamnose and muramic acid as chemical markers for the direct detection of bacterial cell wall degradation products in mammalian tissues. The analysis of carbohydrate markers for bacteria by gas chromatography-mass spectrometry has great potential for use in clinical identification of isolated bacteria as well as in the rapid diagnosis of bacterial infections without prior culture.

Animals↗
PubMed1987

Effects of pretreatment with benzo[a]pyrene on the stereochemical selectivity of metabolic activation of benzo[a]pyrene to DNA-binding metabolites in hamster embryo cell cultures.

The proportions of individual benzo[a]pyrene (BaP)-DNA adducts present in rodent embryo cell cultures change with the length of time of exposure to BaP; the major alteration is an increase in the proportion of (+)-anti-7,8-dihydroxy-9,10-epoxy-7,8,9,10-tetrahydroBaP (BaPDE)-deoxyguanosine (dG) adduct (Sebti et al., Cancer Res., 45 (1984) 1594-1600). To determine if this change in the BaP-DNA adducts could result from the induction of enzymes involved in oxidation of BaP, hamster embryo cell cultures were exposed to acetone or BaP for 24 h and then the medium was replaced with fresh medium containing [3H]BaP. After 5 h the BaP-pretreated cells had a 30% higher level of binding of BaP to DNA and formed a greater proportion of (+)-anti-BaPE-dG adduct than the acetone-pretreated control group. Cells pretreated for 24 h with BaP and then exposed to [3H]BaP and Actinomycin D for 5 h had a lower level of binding of BaP to DNA and a lower amount of (+)-anti-BaPDE-deoxyguanosine adduct than cells pretreated with acetone and exposed to [3H]BaP for 5 h. In contrast, pretreatment for 24 h with BaP plus Actinomycin D followed by a 5-h exposure to [3H]BaP resulted in a decrease in overall binding of BaP to DNA but had no effect on the amount of (+)-anti-BaPDE-deoxyguanosine adduct. Actinomycin D treatment had no significant effect on either the total amount of BaP metabolized, the formation of primary and water-soluble BaP metabolites, or cell viability, but reduced [3H]uridine incorporation into RNA by more than 65% at all times. These results suggest that induction of specific isozymes of cytochrome P-450 may be involved in the time-dependent increase in the proportion of (+)-anti-BaPDE-DNA adducts in BaP-treated cells. The state of induction of specific isozymes of cytochrome P-450 and the ability of the BaP dose applied to induce them may be major factors in determining the proportion of BaP metabolized to (+)-anti-BaPDE, the most carcinogenic stereoisomer of BaPDE.

7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide↗
PubMed1987

Metabolism and DNA adduct formation of benzo[a]pyrene and 7,12-dimethylbenz[a]anthracene in fish cell lines in culture.

The metabolic activation of the carcinogens benzo[a]pyrene (BP) and 7,12-dimethylbenz[a]anthracene (DMBA) was examined in cell lines derived from bluegill fry (BF-2), rainbow trout (RTG-2) and brown bullhead (BB). All three cell lines metabolized BP (0.5 microgram/ml medium) almost completely to water-soluble metabolites within 120 h, but the maximum amount of BP bound to DNA ranged from only 5 pmol/mg DNA in the BF-2 cells to 17 in the BB cells and 44 in the RTG-2 cells. The major BP-DNA adduct in the BB and BF-2 cells was that formed by reaction of (+)-anti-BP-7,8-diol-9,10 epoxide [(+)anti-BPDE] with deoxyguanosine. This adduct was also present in the RTG-2 cell DNA, but there were larger amounts of unidentified polar BP-DNA adducts. Exposure of the cells to [3H]BP-7,8-diol, a metabolic precursor of (+)anti-BPDE, resulted in binding of 1.5, 12 and 35 pmol BP per mg DNA in the BF-2, BB and RTG-2 cells, respectively. More than 90% of the BP-7,8-diol added to the BF-2 cultures was recovered as a glucuronic acid conjugate, but the RTG-2 cells formed more glutathione conjugates than glucuronide conjugates. The BB cells formed both types of conjugates at a slower rate for more than 75% of the 7,8-diol was recovered unchanged after 24 h. The three cell lines differed in the proportion of a 0.1 microgram/ml dose of DMBA metabolized in 48 h: the values ranged from 47% in the BF-2 cells to 78% in the BB cells and 97% in the RTG-2 cells. The amount of DMBA bound to DNA ranged from 4.7 to 8.6 pmol/mg DNA in the three cell lines: DMBA-3,4-diol-1,2-epoxide (DMBADE) adducts were present in the BB cell DNA, but no significant amounts of DMBADE-DNA adducts were detected in the RTG-2 or BF-2 cell DNA. These results demonstrate that fish cell cultures can activate BP to an ultimate carcinogenic metabolite, (+)anti-BPDE, but the level of binding of this metabolite to DNA is much lower than that which occurs in rodent embryo cell cultures. In BF-2 cell cultures formation of BP-7,8-diol-glucuronide effectively prevents the activation of this diol to (+)anti-BPDE. A substantial proportion of the BP-7,8-diol is also metabolized to glucuronide and glutathione conjugates in BB and RTG-2 cells. DMBA also binds to DNA at very low levels in these fish cell cultures. Thus effective conjugation of diols and their metabolites by fish cell lines appears to greatly reduce metabolic activation of hydrocarbons through the bay-region diol epoxide pathway that predominates in mammalian cell cultures.

7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide↗
PubMed1986

Development of a rapid extraction and high-performance liquid chromatographic separation for amitriptyline and six biological metabolites.

The development of a rapid high-performance liquid chromatographic method for the determination of amitriptyline, amitriptyline-N-oxide, 10-hydroxyamitriptyline, 10-hydroxynortriptyline (E and Z isomers), nortriptyline and desmethylnortriptyline in plasma and liver tissue is described. A liquid--liquid extraction with hexane--butanol and back-extraction into phosphoric acid provides efficient extraction of amitriptyline-N-oxide along with amitriptyline and the other metabolites. A Supelcosil C8 reversed-phase column with 5-micron packing and a methanol--sodium phosphate buffer--amine modifier mobile phase was used. The combination of mobile phase pH and amine modifier concentration for the best separation within a reasonable analysis time for all seven solutes plus an internal standard was determined using a factorial design coupled with a multi-factor window diagram technique. Ultraviolet detection at 214 nm provided limits of detection of approximately 1 ng/ml.

Amitriptyline↗
PubMed1985

Modifications in the alditol acetate method for analysis of muramic acid and other neutral and amino sugars by capillary gas chromatography-mass spectrometry with selected ion monitoring.

Two alditol acetate methods for the gas chromatographic (GC) analysis of neutral and amino sugars were compared. Following sodium borohydride reduction, one method uses methylimidazole as an acetylation catalyst without prior removal of water or borate salts and the other method uses sodium acetate after removal of borate and water. Depending on the acetylation conditions, muramic acid produced different derivatives. With methylimidazole, reliable derivatization of muramic acid was not possible, although other sugars derivatized reliably. With sodium acetate, all sugars tested were reproducibly derivatized. The utility of the sodium acetate method is shown by the trace GC-mass spectrometric analysis of muramic acid and rhamnose derived from bacterial peptidoglycan-polysaccharide complexes in mammalian tissue.

Acetylation↗