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Biomedical subjects

R S Summers

Publications and source records attributed to R S Summers.

At least 19 recordsLinked to original sources
PubMed2001

Comparative measurements of microbial activity in drinking water biofilters.

Tetrazolium reduction assays, phospholipid analysis, and 16S rRNA (rDNA) sequence analysis were applied to assess the distribution, composition and activity of microbial communities developing in biofilters treating non-ozonated and ozonated drinking water. The response of media-attached biomass to both operating temperature (3 degrees C vs. > 12 degrees C) and ozone application point was assessed. As judged by 2-(p-iodo-phenyl)-3-(p-nitrophenyl)-s-phenyl tetrazolium chloride (INT) reduction, the dehydrogenase activity in biofilter systems that were operated with non-ozonated water was 55% lower than in identical filters operating with ozonated water. There was no significant difference between the microbiological activity measured in a biofilter series treating ozonated water and an identical series where ozonated water was introduced at an intermediate point. The biomass levels in biofilter systems that were operated with ozonated water were 47% higher on average than identical systems operated with non-ozonated water. Operating temperature had no significant impact on total biomass levels; however, specific dehydrogenase activity was 70% higher in systems operated at ambient temperatures (> 12 degrees C) than in systems held at 3 degrees C. Phospholipid and rDNA analysis suggests that there was a community structure response to ozone application and operating temperature, but no response to different ozone application points.

Biomass↗
PubMed2001

Randomized, controlled trial of prescribing training in a South African province.

OBJECTIVES: Prescribing practices impact greatly on drug use and expenditure. The situation in developing countries is often compounded by a limited health budget. Furthermore, because of role substitution in these countries, prescribers are often not formally trained in rational prescribing. The study described in this paper assesses the effect of a prescribing training intervention for primary health care nurses. DESIGN: A generic training-of-trainers course and a 4-day effective prescribing course were presented to 24 provincial trainers. These trainers then conducted effective prescribing workshops for 20 primary health care nurses per workshop. In 1997, 457 prescribers were trained by this method in South Africa's Northern Province. The study investigated the impact of the training on prescribing practices for two target conditions, in a control and a study group of 11 clinics each, 1 month after and 3 months after the intervention. SETTING: Primary health care clinics in the Lowveld Region of the Northern Province of South Africa. RESULTS: Prescribing practices for the two conditions examined were significantly improved by the training. Changed behaviour was not only seen in prescribing for upper respiratory tract infections, used as an example condition, but also for diarrhoea and/or vomiting, a common condition in the region, which was not included in the training programme. These results show that prescribers not only retained the knowledge gained, but were also able to apply their new skills to other conditions (transfer effect). The change in the study group was maintained for 3 months after training, while there were no significant improvements in prescribing in the control group. INTERPRETATION: The training intervention had a beneficial effect on prescribing practices.

Drug Prescriptions↗
PubMed2000

A national database for essential drugs in South Africa.

In the process of drafting standard treatment guidelines for adults and children at hospital level, the Secretariat of the National Essential Drugs List Committee made use of a database designed with technical support from the School of Pharmacy, MEDUNSA. The database links the current 697 drugs on the Essential Drugs List with Standard Treatment Guidelines for over 400 conditions. It served to streamline the inclusion of different drugs and dosage forms in the various guidelines, and provided concise, updated information to other departments involved in drug procurement. From information on drug prices and morbidity, it can also be used to calculate drug consumption and cost estimates and compare them with actual figures.

Adult↗
PubMed1998

Microbial characterization of biological filters used for drinking water treatment.

The impact of preozonation and filter contact time (depth) on microbial communities was examined in drinking water biofilters treating Ohio River water which had undergone conventional treatment (coagulation, flocculation, sedimentation) or solutions of natural organic matter isolated from groundwater (both ozonated and nonozonated). With respect to filter depth, compared to filters treating nonozonated waters, preozonation of treated water led to greater differences in community phospholipid fatty acid (PLFA) profiles, utilization of sole carbon sources (Biolog), and arbitrarily primed PCR fingerprints. PLFA profiles indicated that there was a shift toward anaerobic bacteria in the communities found in the filter treating ozonated water compared to the communities found in the filter treating nonozonated settled water, which had a greater abundance of eukaryotic markers.

Filtration↗
PubMed1993

Plasma vitamin A levels in measles and malnourished pediatric patients and their implications in therapeutics.

Measles and protein energy malnutrition (PEM) in children have been associated with low serum retinol levels. Vitamin A supplementation has reduced mortality and morbidity significantly. The purpose of this study was to determine the effect of vitamin A supplementation on plasma retinol levels in children with these conditions. Black, African children, admitted to Ga-Rankuwa Hospital with measles or PEM, were randomly allocated to either a study or a control group. The study group received, in addition to routine treatment, 150,000 units of vitamin A palmitate IM on day 1 followed by 15,000 units orally for 7 days. The patients in the control group received routine appropriate treatment, which may have included 3000 units vitamin A per day. Retinol plasma concentrations of all patients were measured on days 1, 2, and 8. The mean baseline plasma retinol levels (day 1) of both the measles and PEM patients were lower than 11 micrograms/dl. There was a statistically significant increase in plasma levels in the study and control groups for both conditions by day 8 with the mean plasma retinol levels > 30 micrograms/dl. There was no statistically significant difference between study and control groups. This study has shown that there is a high incidence of baseline hyporetinaemia in these patients. The mean retinol plasma levels return to within normal limits after 8 days of either routine treatment or vitamin A supplementation.

Child↗
PubMed1992

Immunogenicity of recombinant hepatitis B vaccine in urban black children from Ga-Rankuwa, Bophuthatswana, South Africa.

Many areas in Southern Africa have a relatively high endemicity for hepatitis B for which the only effective medical measure is vaccination. The aim of this study was to evaluate the antibody response to a recombinant hepatitis B vaccine (Engerix B; Smith Kline-Beecham) in a black urban population, with the use of the recommended regimen and a low dose, short course. One hundred eleven children seronegative for hepatitis B virus (5 to 19 years old) were randomized to receive one of the two vaccination schedules (20 micrograms at zero, 1 and 6 months or 2 micrograms at zero, 1 and 2 months). Antibody to hepatitis B surface antigen was determined 6 to 8 weeks after the last dose by radioimmunoassay (Ausab; Abbott Laboratories). The recommended schedule gave a seroconversion rate of 100% with a geometric mean titer of 585.9 mIU/ml. The low dose, short course schedule produced a seroconversion rate of 63.8% and a geometric mean titer of 73.8 mIU/ml. In the 5- to 9-year-old individuals, however, 71.6% seroconverted (geometric mean titer 114.2 mIU/ml). For cost reasons further investigations on low dose regimens are indicated.

Adolescent↗
PubMed1991

Evaluation of a communications skills workshop for hospital pharmacists.

The ability to communicate is an essential requirement for effective practice. Until recently, however, pharmacy students received no training in this area. The resultant inadequacy was carried forward into practice. Only now has the omission been recognized and attempts made to improve the situation among practising pharmacists. We designed an 8-h workshop on communication skills. It covered the basic principles of communication (Workbook A--preparatory work before the workshop) and their application (Workbook B + case studies, exercises and role-playing--during the workshop). The workshop was presented to a group of hospital pharmacists in the Western Cape. At the end of the workshop participants completed a questionnaire on its usefulness, applicability and presentation on a five-point scale. Responses were counted, averaged and analysed by sex and age. Although the ratings were uniformly high (average 4.3 out of a possible 5.0) there were differences between men and women and between older and younger pharmacists. The possible reasons for and implications of these differences are discussed.

Adult↗
PubMed1990

Benzodiazepine use in a small community hospital. Appropriate prescribing or not?

Benzodiazepine (BDZ)-prescribing patterns in relation to indications and to drug characteristics in a small short-stay hospital were examined. In a sample of 800 patients, 183 were prescribed BDZs during their stay. Female patients received more BDZs (BDZ:female patients 1.31:1.0) than males (BDZs:male patients 1.02:1.0), particularly in the 21-40-year age group in which polypharmacy was highest. BDZs were classified according to their elimination half-lives. Our data showed that the majority fell into the long-acting (half-life greater than 24 h) (55%) and intermediate-acting (half-life 12-24 h) (20.7%) categories, despite the fact that most indications (pre-anaesthetic and night-time sedation; total 71.6%) called for the shorter-acting drugs. The merits or otherwise of this situation are discussed, and a number of questions put regarding the validity of this approach. Overall, BDZs accounted for 5.8% of the calculated medications given to the 800-patient sample.

Adolescent↗
PubMed1989

Carbamazepine clearance in paediatric epilepsy patients. Influence of body mass, dose, sex and co-medication.

Carbamazepine clearance was studied in Black paediatric epilepsy patients, 90 receiving monotherapy and 17 on combination therapy. For patients on monotherapy the following relationship are shown: clearance decreases with increasing body mass (r= 0.87); clearance increases with increasing dose (r = 0.70); and mean clearance for male are higher than those for females throughout the mass ranges, though the difference is not statistically significant. In the case of patients on carbamazepine plus another anticonvulsant, clearance also decreases with increasing body mass, and increases with increasing dose. Furthermore, in the mass groups which corresponded with those on monotherapy, mean carbamazepine clearance higher by a factor varying from 1.3 to 1.7; in the corresponding dosage groups, it is higher by a factor of between 1.4 and 1.7.

Biological Availability↗
PubMed1987

Changes in pharmacy practice due to a clinical pharmacy training programme for a group of community hospitals.

Education for and the practice of Clinical Pharmacy in South Africa have been neglected. This paper describes one attempt to improve matters. An initial survey of pharmacies, pharmacists and other staff in a small group of private hospitals determined the level of Clinical Pharmacy organization and services. The results were used to design a Clinical Pharmacy (training) Programme for selected pharmacists in the group. The programme consisted of six units, each of which was presented in at least a full-day session, with strong audiovisual support, small group discussion and rigorous exercises. During and after each session, implementation and application in the respective hospitals were monitored, as were participants' reactions. Clinical Pharmacy services increased markedly as a result of the programme, as did job satisfaction and motivation among most of the participating pharmacists.

Curriculum↗