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Biomedical subjects

J Hamilton

Publications and source records attributed to J Hamilton.

At least 91 records · Page 5Linked to original sources
PubMed1995

Montreal Museum exhibit provides clear picture of advances in medical imaging.

An exhibit at the McCord Museum of Canadian History, which runs until November, marks the centennial of the discovery of the x-ray. Among the items on display are a portable field x-ray machine used during World War I and one of the machines commonly found in shoe stores between 1930 and 1950 to x-ray customers' feet. The exhibit also features one of the first scanners used in North America. Dr. Denis Melançon, a radiologist at the Montreal Neurological Institute, was the driving force behind the McCord exhibit. "I wanted to show [not only] the historical and scientific aspects of the discovery, but also its medical and social applications," he says.

Exhibitions as Topic↗
PubMed1995

A question of rhythm: recent advances in growth hormone research.

Research by Dr. Gloria Shaffer Tannenbaum at the McGill University-Montreal Children's Hospital Research Institute has led to the development of a new test to differentiate children who are deficient in growth hormone from those who are short but growing normally. This clinical application is the fruit of Tannenbaum's discovery that growth hormone secretion occurs in a rhythmic pattern regulated by intricate interactions between two neurohormones: growth hormone-releasing hormone (GHRH) and somatotropin release-inhibiting factor (SRIF). In the test an analogue of SRIF is used to allow stores of growth hormone to build up. A subsequent challenge with GHRH is then used to identify children with a genuine deficiency. Tannenbaum's research also indicates that there are sexual differences in the pattern of growth hormone release and that growth hormone regulates its own secretion by means of a negative feedback system.

Growth Disorders↗
PubMed1995

Dr. Balfour Mount and the cruel irony of our care for the dying.

Dr. Balfour Mount of Montreal thinks that the health care system, because of its fixation on disease processes, may have forgotten that it also has a mandate to alleviate suffering. "We need to recapture that vision," says Mount, who describes palliative medicine as a "rich combination" of clinical pharmacology, rehabilitation medicine and internal medicine. Mount says there is a cruel irony in our care of the dying. "Although these are the sickest people in our health care system, when medical technology doesn't know what to do, the quality and quantity of care falls away. How can we justify that?"

Canada↗
PubMed1995

Organization for rural MDs focuses "on problems that separate us from our urban counterparts".

Physicians in rural Canada face much different problems than their counterparts in large cities, a recent conference for rural physicians was told. For instance, rural areas may be decimated by funding caps because "they didn't have any resources to give up in the first place," said Dr. Ken Babey. He said rural physicians don't want to create divisiveness between urban and rural doctors, "but people don't realize that when they do something that has a big impact on the doctors who practise in cities and suburban areas, it has a disastrous impact on us." Rural doctors are attempting to organize so they can present a united front; in Nova Scotia, physicians recently formed a Section of Rural Practice.

Canada↗
PubMed1995

Ingestive response shows absence of taste aversion after bovine satietin in rats.

Six adult male rats (409 +/- 16 g) were equipped with chronically implanted oral catheters. Facial consummatory responses to gustatory stimuli, of 50 microliters 2.0 mol.1-1 banana or coconut flavoring, were recorded on a +4/-4 scale for 30 s. The new flavors were paired with IP injections on three different days. The rats were injected with either saline or 1 mg.kg-1 bovine serum satietin (bs-SAT). Food intake and body weight were reduced (p < 0.005) after satietin but not after saline. Both coconut and banana flavors aroused mild ingestive responses in the naive rats. Five days after the beginning of the pairing with IP injections, the rats' response to coconut and banana remained unchanged. The results show that satietin was able to reduce food intake and body weight but did not arouse taste aversion.

Animals↗
PubMed1995

Modified Pereyra bladder neck suspension: 10-year mean followup using outcomes analysis in 125 patients.

PURPOSE: We attempt to determine the long-term success rate of the modified Pereyra bladder neck suspension, identify preoperative factors predictive of long-term outcome, and investigate the influence of method and length of followup on reported continence status after modified Pereyra bladder neck suspension. MATERIALS AND METHODS: The charts of 177 patients who underwent modified Pereyra bladder neck suspension at our institution more than 5 years ago were reviewed. An attempt was made to contact all patients either by mail or telephone to complete a patient survey questionnaire. RESULTS: Of 177 patients 125 (71%) completed the patient survey with a mean followup of 9.8 years. At survey followup 20% of the patients reported no incontinence of any type and 51% reported stress urinary incontinence with or without urge incontinence. Of the patients 71% reported significant improvement in the incontinence and 73% were satisfied with the results of the procedure. No accurate preoperative predictors of long-term outcome were identified. The method and length of followup had significant impact on reported continence status after modified Pereyra bladder neck suspension. CONCLUSIONS: This long-term study using outcomes analysis reveals a high rate of recurrent stress incontinence after modified Pereyra bladder neck suspension. However, most patients maintain significant subjective improvement and remain satisfied with the results of the operation.

Female↗
PubMed1995

The treatment of node negative squamous cell carcinoma of the postcricoid region.

This study includes 155 patients with T1-4N0 carcinoma of the postcricoid region seen between 1963 and 1993. Sixty-seven were treated by primary surgery, 50 by primary irradiation therapy, 36 were unsuitable for curative treatment and two patients were lost to follow-up. Reasons for deciding against curative therapy were: advanced age, poor general condition and advanced disease at the primary site. This study included only those patients who had no neck node metastases at presentation. Patients receiving surgery tended to be in better general physical condition and tended to have more advanced disease than those treated by irradiation in this series. The tumour-specific five-year survival rate for those treated by surgery was 43 percent (95 percent confidence interval (CI) 23-60 percent). For those patients treated by irradiation the five-year survival rate was 48 percent (95 percent CI 27-66 percent) and for those receiving no treatment the median survival rate was three months (95 percent CI two-six months). The observed survival for the surgery group was only 18 percent and for the radiotherapy group 25 percent at five years. Multiple logistic regression showed no significant difference in proportions of host and tumour factors between the group receiving radiotherapy and the group receiving surgery. Recurrence at the primary site and the appearance of neck node metastases were not predicted by any host or tumour factor. Twenty-one patients out of 67 receiving primary surgery had recurrence at the primary site compared with 26 patients out of 50 receiving primary irradiation.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1995

A study of alpha-amylase activity in tracheobronchial secretions of seriously ill patients with tracheostomies.

This study was undertaken to assess any salivary aspiration in seriously ill patients with tracheostomies in an Intensive Care Unit setting. The alpha-amylase activity in the tracheostomies in an Intensive Care Unit setting. The alpha-amylase activity in the tracheobronchial secretions of 15 such patients were analysed to evaluate the incidence of salivary aspiration. None of the patients had clinical or radiological evidence of lung disorder at the time of the commencement of the study. Six out of 15 patients showed very high levels of alpha-amylase activity in their tracheobronchial secretions on Day 3 and all six subsequently developed severe chest infections. The other nine patients showed a low level of amylase activity in their secretions. Two patients in the latter group developed severe pulmonary disease. This study demonstrates that a high level of alpha-amylase activity in the tracheobronchial secretions of tracheotomized, ventilated patients indicates that salivary aspiration may be taking place, and further suggests that progressively increasing levels may indicate the likelihood of a major pulmonary complication developing.

Adult↗
PubMed1995

Resistance, humidity and temperature of the tracheal airway.

Patients after laryngectomy are subject to a high incidence of chest complaints. In attempting to reduce these a number of 'new nose' stoma filters have recently been introduced which claim to humidify and warm air, filter particulate matter and, by increasing tracheal airway resistance, to improve lung function. Our study defines the normal tracheal temperature, humidity and resistance values which were obtained from 16 patients with a normal upper respiratory tract. These parameters will allow the available filters to be evaluated objectively and may lead to the development of a more physiological 'new nose'.

Airway Resistance↗
PubMed1995

Embarking upon a medical career: psychological morbidity in first year medical students.

This study was undertaken to measure the prevalence of psychological morbidity, and the nature and source of stress, in first year medical students. Two hundred and four first year medical students at a university in the north of England were sent a postal, self-report questionnaire. They were asked to complete the General Health Questionnaire (GHQ), the Stress Incident Record and to give details of their alcohol consumption. A total of 172 students (84.3%) replied. Thirty-six per cent of the students scored above the threshold of the GHQ, indicating probable psychological disturbance. There was no difference between men and women. Approximately half of the students described a stressful incident, the majority of which were related to medical training rather than to personal problems. Male students reported drinking significantly more alcohol than female students, but there was no relationship between levels of alcohol consumption and either psychological disturbance or reporting of stress. The findings suggest that even at the preliminary stages of medical training, many students find aspects of the medical course very stressful. The psychological well-being of medical students needs to be more carefully addressed, and closer attention paid to the styles of medical teaching that may provoke avoidable distress.

Alcohol Drinking↗
PubMed1995

Training for skills.

The World Federation for Medical Education Summit in Edinburgh in 1993 called for bold, clear, attractive and feasible strategies to equip doctors with the skills for the future of health care. There was special emphasis on skills for problem-solving, ethical and evidence-based medicine, effective communication, health promotion and illness prevention, and to educate and be educated. There were also skills for the shaping of the future of health services to form partnerships with other professionals and communities, to promote primary health care and to respond to culture and context. Strategies for effective training for skills include linking them to knowledge and attitude, selection of students of aptitude and motivation, training through practice with feedback, training teachers and assessors, and the reinforcement of skills after graduation. This presentation describes practical examples of these strategies in action to address each of the identified skills, all of them based on experience in the real world in Australia and Nigeria.

Delivery of Health Care↗
PubMed1994

Characterisation of six additional human metallothionein genes.

Human metallothionein (MT) genes are clustered in a locus on chromosome 16, and this report presents the characterisation of the remaining six univestigated members of the family. Nucleotide sequencing in whole or part suggested that four of these genes, MT1I, MT1J, MT1K and MT1L do not encode expressed MT proteins, based on the presence of structural faults or atypical amino acid assignments. On the other hand, the structures of MT1H and MT1X are consistent with these genes being functional and encoding unique type 1 isoforms. The promoters of both genes conferred activity to CAT expression constructs when transfected into HeLa cells, and showed differential responses to inducers MT synthesis. Endogenous MT1H and MT1X genes were expressed at the mRNA level in HeLa cells following cadmium treatment. This work brings the number of functional class 1 and 2 MT genes in the human to eight, and confirms that each encodes structurally unique proteins.

Amino Acid Sequence↗