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Biomedical subjects

M Donaldson

Publications and source records attributed to M Donaldson.

At least 37 records · Page 2Linked to original sources
PubMed1995

Atypical androgen receptor in the human melanoma cell line IIB-MEL-J.

To evaluate the presence of androgen receptors in the human melanoma cell line IIB-MEL-J, a Scatchard plot analysis was performed. Cells in culture revealed a single binding component with an apparent dissociation constant (KD) at 37 degrees C of 11 nM and a binding capacity of 326 fmol/mg protein when measured with [3H]-R1881. Competition analysis revealed an atypical relaxation of specificity, since not only androgen (testosterone, dihydrotestosterone [DHT], R1881) and antiandrogen (hydroxy-flutamide [OH-FLU]) competed for [3H]-R1881 binding, but also estradiol, progesterone, and cortisol at 500-fold excess concentration. Binding of [3H]-estradiol and [3H]-R5020 in the absence of unlabeled DHT were completely suppressed in its presence. Immunohistochemistry of androgen receptor with a monoclonal antibody showed that nuclei were vigorously stained. Different doses of flutamide (FLU) and OH-FLU tested on cultured IIB-MEL-J cells in the presence of serum inhibited significantly cell proliferation in a dose-dependent manner. When cells were incubated with 10 nM DHT and 1% charcoal-adsorbed serum, a significant stimulation of growth that was observed was inhibited by 4 microM OH-FLU. DHT stimulation was completely reversed by the antiestrogen tamoxifen. In addition, male nude mice transplanted with IIB-MEL-J tumor were treated with FLU when tumors were palpable. FLU was effective in diminishing tumor growth and increasing survival rate of the animals. As a conclusion, the presence of functional androgen receptors in these cells has been demonstrated by growth inhibition in vitro and in vivo with antiandrogens, and their atypical nature is suggested by binding cross-reactivity and competition studies.

Androgen Antagonists↗
PubMed1994

The effects of weight loss in obese subjects on the thermogenic, metabolic and haemodynamic responses to the glucose clamp.

The aim of this work was to examine the effects of weight loss in obese subjects on the thermogenic, metabolic and cardiovascular responses to a glucose clamp. Resting measurements were made, followed by a hyperinsulinaemic (100 mU/m2/min) euglycaemic clamp (4.5 mmol/l). The subjects were six healthy, obese subjects (mean body mass index before weight loss 37.0 +/- 1.7 kg/m2 and after weight loss 31.4 +/- 2.3 kg/m2). The following measurements were made: indirect calorimetry, blood pressure, heart rate, forearm blood flow, plasma catecholamines, plasma deuterated glucose turnover before and during a glucose clamp. Glucose disposal during the clamp increased from 2.53 +/- 0.40 to 3.31 +/- 0.42 mmol/min after weight loss (P < 0.01). Glucose-induced thermogenesis rose from 0.15 +/- 0.09 to 0.50 +/- 0.12 kJ/min (P < 0.05). The apparent cost of glucose storage was not significantly different from zero prior to weight loss, but increased to 11.0 +/- 2.2% after weight loss. In response to the clamp endogenous glucose production was suppressed by 66 +/- 7% initially and this was not affected by weight loss. Weight loss was accompanied by increased peripheral insulin sensitivity and glucose-induced thermogenesis, but it did not affect hepatic insulin sensitivity.

Adult↗
PubMed1993

Hepatitis B prevalence in local authority employees.

Prevalence of hepatitis B infection was determined in 420 employees from three local authorities by testing for hepatitis B core antibody (anti-HBc). Five (1.2 per cent) were positive: this included a hepatitis BsAg carrier, three with antibody to hepatitis BsAg (anti-HBs) and one who had only anti-HBc. The prevalence of hepatitis B was not significantly different (P > 0.05) from a control group of blood donors. However, four out of five anti-HBc positive individuals worked with mentally or physically handicapped individuals or those discharged into the community after long-term institutionalized care.

Adolescent↗
PubMed1993

Computer-Assisted Retrospective Clinical Activities Statistics (CARCAS) Program.

Clinical pharmacy services have been demonstrated to have a positive impact on patient care in the hospital setting. Accurate and complete documentation of interventions aimed at improving drug use is essential to assess workload characteristics, determine the impact of pharmacist activities, justify current programs and predict future clinical staffing requirements. The need for an improved system of collecting and analyzing clinical workload statistics led to the development of a Computer-Assisted Retrospective Clinical Activities Statistics (CARCAS) Program in our department. Using a pre-defined clinical activity coding system, pharmacist activities were efficiently documented on a daily basis using an existing distributional computer system. Training requirements and data entry time were minimal. The CARCAS Program appeared to capture more clinical pharmacist activities than the earlier manual system. The flexibility of the CARCAS Program should permit adaptation to other hospitals with similar computer systems regardless of the nature of their clinical programs.

British Columbia↗
PubMed1993

[Pregnancy with spermatozoa from the head of the epididymis in spermatic duct agenesis].

From a male affected of agenesis of corpus and cauda epididymis and vas deferens, sperms were surgically obtained aspirating epididymal content with the help of a surgical microscope. Motile sperms were separated after discontinuous Percoll gradient centrifugation and used to inseminate in vitro the spouse's oocytes 8 hrs. after aspiration according to the current techniques. Twenty hours later, oocytes were checked for fertilization and transferred to fresh culture medium. From 13 preovulatory oocytes only one was fertilized and transferred to the Fallopian tube at the 6 cells stage. Fourteen days after embryo transfer, serum HCG concentration was 320 mU/ml and on day 29th a 5mm fetal sac showing heart beats was detected by transvaginal sonography. After an uneventful 38 weeks gestation a normal baby girl weighing 2,800 g was delivered.

Adult↗
PubMed1991

The pre-registration house officer year: a critical incident study.

To define the major problems faced by pre-registration house officers, 328 critical incidents from 200 house officers and related staff were collected. Each incident was analysed and key words representing the main features were abstracted. These were then aggregated into eight broad categories; personal aspects, clinical skills, communication and relationships, problem-related, organization skills, education, dying patients, and administration. Further analysis of the incidents suggested a series of conclusions which include the need for effective supervision of the house officer with feedback on performance. An induction/orientation period is necessary; there is evidence that a proportion of house officers need additional experience of practical procedures; house officers often have difficulty in setting priorities and they have little experience, prior to qualification, of organizational skills; during the year they are very busy with little time off. Facilities and accommodation may be less than adequate. They perceive a lack of support from senior staff to help with personal problems and career guidance; they are conscious that communication skills are of great importance and would like additional help with this; there is little time for formal education during the year. The range of clinical material presented is enormous, however, and the challenge for medical education is to ensure that the opportunities for learning are not missed.

Clinical Competence↗
PubMed1985

Career aspirations of geriatric medicine trainees.

The views of trainees in geriatric medicine on preferred career styles were studied by questionnaire. As expected, the majority of respondents did not intend a career in geriatric medicine upon graduation. Whilst a majority would prefer a post wholly dedicated to the care of elderly patients, half the sample would prefer their service to be integrated with general medical services. The majority are optimistic for the future of geriatric medicine in the United Kingdom.

Age Factors↗
PubMed1984

Characterization of Ross River viruses isolated from patients with polyarthritis in New Caledonia and Wallis and Futuna Islands.

Viruses isolated during 1979 and 1980 from patients with polyarthritis in New Caledonia and Wallis and Futuna Islands have been found to be more closely related to Ross River virus than any other regional Alphavirus. On the basis of virulence in suckling mice the majority of these isolates were found to be more closely related to the NB5092 strain of Ross River virus than to the prototype T48 strain.

Alphavirus↗
PubMed1984

Early experience with in situ saphenous vein grafts for severe ischemia of the lower extremity.

Based upon this group of 35 patients with a variety of vascular lesions, it would appear that the in situ saphenous vein technique is certainly, at least, a viable alternative to standard bypass techniques. It has been applied with equally encouraging results by several surgeons in a variety of clinical settings, all using the procedure for the first time in a learning phase. This technique may become the procedure of choice for the treatment of occlusive disease of the lower extremity in this difficult and challenging group of patients.

Blood Vessel Prosthesis↗