Search PubMed⌕ Search

Biomedical subjects

M A Harris

Publications and source records attributed to M A Harris.

At least 127 records · Page 7Linked to original sources

The effect of biopsy on survival of patients with osteosarcoma.

A retrospective study of patients with osteosarcoma was undertaken to determine whether there was a relationship between biopsy and survival. Fifty-seven patients treated at the Karolinska Hospital, Stockholm, between 1938 and 1959 were included in this study, all of whom were less than thirty years old, had a metaphysial osteosarcoma in a long bone but had no pulmonary metastases at the time of diagnosis; all were treated by amputation. No clinical variants of osteosarcoma were included. Twenty-four of the fifty-seven patients had an amputation without a prior biopsy; the others had biopsies before amputation. These two groups were fairly closely matched in age, sex, site and size of tumour, and in the level of amputation; some patients in each group received radiation before operation. Evaluation of these two groups of patients revealed that the performance of a biopsy, with or without a delay of not more than thirty days between the biopsy and the definitive operation, had no adverse effect on survival.

Adolescent↗

Hydrogenase activity and the H2-fumarate electron transport system in Bacteroides fragilis.

Hydrogenase activity and the H(2)-fumarate electron transport system in a carbohydrate-fermenting obligate anaerobe, Bacteroides fragilis, were investigated. In both whole cells and cell extracts, hydrogenase activity was demonstrated with methylene blue, benzyl viologen, flavin mononucleotide, or flavin adenine dinucleotide as the electron acceptor. A catalytic quantity of benzyl viologen or ferredoxin from Clostridium pasteurianum was required to reduce nicotinamide adenine dinucleotide or nicotinamide adenine dinucleotide phosphate with H(2). Much of the hydrogenase activity appeared to be associated with the soluble fraction of the cell. Fumarate reduction to succinate by H(2) was demonstrable in cell extracts only in the presence of a catalytic quantity of benzyl viologen, flavin mononucleotide, flavin adenine dinucleotide, or ferredoxin from C. pasteurianum. Sulfhydryl compounds were not required for fumarate reduction by H(2), but mercaptoethanol and dithiothreitol appeared to stimulate this activity by 59 and 61%, respectively. Inhibition of fumarate reduction by acriflavin, rotenone, 2-heptyl-4-hydroxyquinoline-N-oxide, and antimycin A suggest the involvement of a flavoprotein, a quinone, and cytochrome b in the reduction of fumarate to succinate. The involvement of a quinone in fumarate reduction is also apparent from the inhibition of fumarate reduction by H(2) when cell extracts were irradiated with ultraviolet light. Based on the evidence obtained, a possible scheme for the flow of electrons from H(2) to fumarate in B. fragilis is proposed.

Acriflavine↗

Anaerobic bacteria from the large intestine of mice.

Anaerobic bacteria from the colon of laboratory mice were enumerated and isolated using strict anaerobic techniques. Direct microscopic counts revealed 4.4 X 10(10) organisms in each gram (wet weight) of colon contents. Actual cultural counts averaged 3.2 X 10(10) organisms, which was 73% of the direct microscopic count. The tentatively identified genera were Bacteroides, Eubacterium, Fusobacterium, Lactobacillus, Peptostreptococcus, and Propionibacterium. Strains of Fusobacterium, Lactobacillus, Peptostreptococcus, and Propionibacterium were biochemically homogeneous. Strains of Bacteroides and Eubacterium, on the other hand, were biochemically heterogeneous and were subdivided into several distinct groups. The data indicate that many of the isolates are different from previously described species of the respective genera and may belong to new species.

Anaerobiosis↗

Expanded health belief model predicts diabetes self-management in college students.

An instrument was designed to determine relationships between constructs of the Expanded Health Belief Model and to identify characteristics of college students who successfully manage their diabetes. The Diabetes College Scale was developed to measure attitudes and behaviors pertinent to diabetes management and college life. It was tested for content validity, test-retest reliability, and internal consistency. Data were collected from college students using a cross-sectional design. Campus health care providers were invited via electronic mail to administer the survey to students with Type I diabetes. Ninety-eight questionnaires were mailed to interested providers, of which 86 (88%) were returned. Mean scores for attitude constructs, seven behaviors, and two outcomes were measured. Twenty-six experts established content validity. Instrument reliability was evaluated using paired t-tests, Cronbach's alpha, and correlation coefficients. Correlation coefficients and stepwise multiple regression analysis evaluated relationships among variables measured. Intention and emotional response were strong predictors of exercise, whereas health importance and intention were predictive of testing blood sugar. Situational factors and emotional response were substantial barriers to optimal diabetes self-care. College health care providers should address these areas in providing services to this population. Additional testing of the instrument is also recommended.

Adolescent↗

A chest injury in an isolated geo-politically sensitive area: questions in management.

The reported case of a stab wound to the chest occurred in an isolated area with no specialized surgical care available. The need for transport and specifically by air, introduced particular questions in management. On a humanitarian basis and in line with its mandate, the Peace Monitoring Group, a United Nations endorsed entity in Bougainville, Papua New Guinea, provided transport to a facility with an appropriate standard of care. The questions of need for patient evacuation and chest drainage, with the timing of this maneuver are considered.

Adult↗

Randomized, controlled trial of behavior therapy for families of adolescents with insulin-dependent diabetes mellitus.

OBJECTIVE: To describe the short-term results of a controlled trial of Behavioral Family Systems Therapy (BFST) for families of adolescents with diabetes. METHODS: We randomized 119 families of adolescents with diabetes to 3 months' treatment with either BFST, an education and support Group (ES), or current therapy (CT). Family relationships, psychological adjustment to diabetes, treatment adherence and diabetic control were assessed at baseline, after 3 months of treatment (reported here), and 6 and 12 months later. RESULTS: Compared with CT and ES, BFST yielded more improvement in parent-adolescent relations and reduced diabetes-specific conflict. Effects on psychological adjustment to diabetes and diabetic control were less robust and depended on the adolescent's age and gender. There were no effects on treatment adherence. CONCLUSIONS: BFST yielded some improvement in parent-adolescent relationships; its effects on diabetes outcomes depended on the adolescent's age and gender. Factors mediating the effectiveness of BFST must be clarified.

Adolescent↗

Development and evaluation of an intervention program: "Control on Campus".

PURPOSE: This study was designed to develop and test an intervention for college students with type 1 diabetes. METHODS: A diabetes program, "Control on Campus," and guide were developed based on the Expanded Health Belief Model and Social Learning Theory. Diabetes knowledge, attitudes, and behaviors were assessed preprogram, postprogram, and at follow-up for 3 intervention cohorts and a control group. RESULTS: Reporting of HbA1c values and diabetes knowledge improved significantly as a result of the intervention compared with no increase in the control group. Furthermore, participants reported feeling more support on campus after the intervention, appeared to have overcome their fears associated with testing their blood glucose, reported an increased frequency of blood glucose testing, and were more likely to test when they felt their blood glucose level was low. CONCLUSIONS: Overall, this research yielded substantial insight into the characteristics of college students with diabetes and was successful in designing and evaluating an intervention trial for this population.

Adolescent↗