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Biomedical subjects

G MacDonald

Publications and source records attributed to G MacDonald.

At least 19 recordsLinked to original sources
PubMed1995

Shared governance--a unit based concept.

Shared governance has been depicted as a way of increasing staff nurse involvement: in work, motivation, quality of worklife, organizational commitment, power to influence patient care, and professional pride. This management style is typically implemented on a corporate basis in non-unionized organizations. However, it was identified as an initiative that could enable staff growth, innovation, autonomy and professionalism on a single nursing unit within a unionized hospital. The process of implementing a Shared Governance model on a 29 bed neuroscience unit in an 850 bed acute care teaching hospital is described.

Decision Making, Organizational↗
PubMed1994

YB-1 DNA-binding protein represses interferon gamma activation of class II major histocompatibility complex genes.

Interferon gamma (IFN-gamma) is the most potent inducer of class II major histocompatibility complex (MHC) genes. This induction is uniquely mediated by three DNA elements in the promoter region of class II MHC genes. One of these DNA elements, Y, contains an inverted CCAAT box. Previously, we have screened a lambda gt11 library for Y-binding proteins and identified the YB-1 gene. Here we provide evidence that YB-1 can repress the IFN-gamma induction of class II MHC promoter as well as the Invariant chain (Ii) gene which also contains a Y element in its promoter. This was demonstrated by cotransfecting a YB-1 expression vector with promoter-reporter gene constructs. As an alternate approach, an efficient transient transfection system was developed which resulted in a > 70% transfection efficiency. Transfection of YB-1 by this procedure resulted in the near abrogation of IFN-gamma induced HLA-DR antigen and mRNA expression. These findings show the functional suppression of class II MHC gene induction by the YB-1 protein.

Animals↗
PubMed1993

Profile of transition homes/shelters for victims of family violence.

This article presents the results of the Transition Home Survey--Supplement to the Residential Care Facilities Survey (RCF) 1991/92. The RCF is an annual survey sponsored by Statistics Canada. The Transition Home Survey was the first national endeavour to gather detailed information on clients and services provided in transition homes for victims of family violence. The target universe consisted of facilities defined as 'transition homes', which include shelters, second stage housing, family resource centres, safe home networks, satellites, emergency shelters and other homes for victims of family violence. The data presented covers four topics--facilities, services, caseload and revenue and expenditures.

Adolescent↗
PubMed1992

Professional attitudes regarding the sexual abuse of children: comparing police, child welfare and community mental health.

A survey was completed involving three of the key professional groups engaged in the investigation and treatment of child sexual abuse. Police, child welfare and community mental health in a large, rural geographic area in Canada completed attitudinal items relating to professional response to child sexual abuse. An empirical scale was created which was comprised of three orthogonal factors, each with acceptable levels of internal consistency: 1) Beliefs in regard to the extensiveness and seriousness of the issue; 2) treatment versus punishment priority; and 3) view regarding identity of those who perpetrate child sexual abuse. Important gender differences were found across professional groupings in attitude toward sexual abuse. Greatest difference in attitude between service sectors was tied to emphasis placed on treatment versus punishment as a primary aspect of professional intervention. Significant differences were found between child welfare and police, the two service sectors most needing a coordinated approach during the "investigative phase" of professional intervention.

Adult↗
PubMed1991

Improvement of silent myocardial ischaemia and reduction of plasma fibrinogen during nisoldipine therapy in occult coronary arterial disease.

The effect of the long-acting calcium channel blocking agent, nisoldipine, on silent myocardial ischaemia due to occult atherosclerotic coronary arterial disease has been evaluated in 12 asymptomatic patients (seven diabetics and five claudicants), none of whom had any history suggestive of ischaemic chest pain or previous myocardial infarction. All patients had normal resting electrocardiograms but positive exercise testing using 16-lead electrocardiographic mapping of the chest wall. They also had silent episodes of ST-segment depression during 24-hour ambulatory (Holter) monitoring. The study was of double-blind, cross-over design with four weeks randomised nisoldipine 10 mg twice daily versus placebo twice daily. Both the exercise test and Holter monitoring were carried out before entry to the trial and at the end of each randomised active and placebo phase. Plasma fibrinogen was also estimated at entry to the trial and at the end of each randomised phase. There were significant reductions in the magnitude (P less than 0.001) and duration (P less than 0.001) of depression of the ST segment on exercise testing and in the number of episodes (P less than 0.01), magnitude (P less than 0.001) and duration (P less than 0.02) of ST-segment depression on Holter monitoring at the end of the nisoldipine phase as compared to the randomised placebo phase. A significant reduction in plasma fibrinogen was also noted at the end of the nisoldipine phase (P less than 0.001). This study demonstrates the efficacy and usefulness of nisoldipine in treating myocardial ischaemia due to occult coronary arterial disease in asymptomatic subjects presenting with diabetes mellitus or intermittent claudication. Its use was associated with reduction in plasma fibrinogen.

Adult↗
PubMed1991

Fine structure physical mapping of the region of mouse chromosome 10 homologous to human chromosome 21.

Comparative mapping of human and mouse DNA for regions of genetic homology between human Chromosome 21 and the mouse genome is of interest because of the possibility of developing mouse models of human trisomy 21 (Down syndrome), understanding chromosome evolution, and isolating novel sequences conserved between the two species. At least two mouse chromosomes are known to carry sequences homologous to those on human Chromosome 21: mouse Chromosome 16 (D21S16h, D21S13h, D21S52h, App, Sod-1, Mx-1, Ets-2, Prgs,Ifnar) and mouse Chromosome 17 (D21S56h, Crya-1, and Cbs). Recently, five additional genes have been mapped within region 21q22 of human Chromosome 21:PFKL, CD18, COL6A1, COL6A2, and S100B. To assign these sequences to specific mouse chromosomes, we used human cDNA probes for COL6A1, COL6A2, CD18, and PFKL and a rat brain cDNA probe for S100B in conjunction with a panel of seven Chinese hamster-mouse somatic cell hybrids segregating mouse chromosomes. The specific chromosome complements of the hybrid cell lines and the presence or absence of hybridizing mouse sequences in their DNAs allow us to assign all five sequences to mouse Chromosome 10, with the assignment of Pfkl reported here for the first time. Analysis of genomic mouse DNA fragments produced by digestion with rare-cutting restriction enzymes and separated using pulsed-field gel electrophoresis allows us to construct a fine-structure physical map of two segments of the region of Chromosome 10 containing these five markers. The five loci span at least 1900 kb of mouse DNA and are consistent with the human order: Pfkl-Cd-18-Col6a-1-Col6a-2-S100b.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Complacency, risk perception and the problem of HIV education.

Many public surveys on the issue of HIV and AIDS have concentrated on the relationship between attitudes and knowledge. Often this relationship has been found wanting or at most tenuous. A recent survey of 1,002 people in Wales has supported these earlier findings, but found additionally that discriminatory and complacent attitudes on AIDS or towards people with the 'AIDS virus' are held by a significant proportion of the population. The survey also discovered that people correctly perceive the risk of HIV infection as being minimal. Depending on the question 17%-65% of the sample expressed discriminatory attitudes towards people that have the 'AIDS virus'. There was also no marked change over previous surveys in the degree of complacency surrounding AIDS. Younger people (aged (15-34) considered themselves to be more at risk of infection with the 'AIDS virus' but overall the perceived risk of infection was low. A sustained low key education programme in a variety of settings and independent of perceived risk is necessary to combat prejudice and complacency.

Adolescent↗
PubMed1990

Double-blind study of dilevalol and captopril, both in combination with hydrochlorothiazide, in patients with moderate to severe hypertension.

Sixty-one patients (41 men, 20 women) aged 29-73 years, with moderate to severe hypertension, were enrolled in a multicentre study to compare the efficacy, safety, and tolerability of dilevalol (D) and captopril (C). At the end of the baseline period, supine diastolic blood pressure (SuDBP) was 105-140 mm Hg on hydrochlorothiazide (HCTZ) 25 mg once daily and placebo t.i.d. Patients were randomly assigned to D + HCTZ (n = 29) or C + HCTZ (n = 32) and entered phase II titration of D (100-800 mg b.i.d.) or C (12.5 mg b.i.d. to 50 mg t.i.d.). If SuDBP was greater than 99 mm Hg, hydralazine was added (25 mg once daily to 50 mg b.i.d.). If SuDBP was less than or equal to 99 mm Hg, patients entered phase III, a 3-month maintenance period. Demographic profiles were not significantly different between the two groups. Baseline supine BP (mean +/- SEM) was similar in the two groups (D + HCTZ: 182 +/- 3/112 +/- 1; C + HCTZ: 179 +/- 4/113 +/- 1 mm Hg), as was baseline standing BP (D + HCTZ: 175 +/- 3/114 +/- 2; C +/- HCTZ: 173 +/- 4/113 +/- 1 mm Hg). At the end of phase II, there were no significant differences between treatments with respect to the changes in BP from baseline.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

Small cell carcinoma of prostate.

Small cell anaplastic carcinoma (SCC) involving the prostate is extremely unusual, either as a primary or as a secondary metastatic focus. A case of SCC presenting as prostatic obstruction and diagnosed with prostate biopsy is presented and the literature reviewed.

Aged↗
PubMed1989

Efficacy of nitrendipine in the treatment of elderly hypertensive subjects, and its effect on cerebral blood flow.

The ability of nitrendipine to control blood pressure (BP) over a 12- or 24-h period was assessed in patients greater than 65 years of age who had a systolic BP (SBP) greater than 170 mm Hg and a diastolic BP (DBP) greater than 100-130 mm Hg. Thirty patients were randomized equally into two groups: Group 1 received the drug once daily and Group 2 received it twice daily after a 2-week run-in on placebo. The study was double blind. BP was recorded 24 h (Group 1) or 12 h (Group 2) postnitrendipine. The study design permitted one dose titration if BP exceeded 170/100 mm Hg after 3 weeks of active therapy when the dose was doubled. Patients received 6 weeks of therapy at the preferred dosage. Patients underwent measurements of cerebral blood flow (CBF) initially and on three further occasions: after the final dose of placebo, and after the first and last doses of nitrendipine. With active therapy, mean SBP and DBP fell in both groups when subjects were in the sitting and standing postures, except that in Group 1 at Week 5 only, standing SBP and DBP were not significantly reduced on the 10 mg once daily regimen. At the preferred dose, eight of the 15 patients in Group 1 and 13 of the 15 patients in Group 2 responded with a reduction of standing DBP of 10 mm Hg or greater, 24 and 12 h, respectively, after the last dose.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1988

Neonatal infraorbital nerve transection in rat results in peripheral trigeminal sprouting.

Retrograde tracing techniques were employed to determine whether transection of the infraorbital (IO) nerve in either newborn or adult rats resulted in peripheral sprouting by undamaged trigeminal (V) axons. The IO nerve was sectioned just behind the vibrissa pad, either on the day of birth or when animals reached at least 60 days of age. After an additional 60 days, the same nerve was retransected in the orbit; horseradish peroxidase (HRP) or diamidino yellow (DY) was injected into the central portion of the vibrissa pad; and animals were killed 2-3 days later. In the neonatally nerve-damaged rats, this procedure invariably labelled primary afferent neurons in both the ipsilateral and contralateral V ganglia. On the ipsilateral side, these cells were located in the caudal portion of the ophthalmic-maxillary region and, less often, in the mandibular division. Their average diameter was 22.6 micron (s.d. = 5.6). On the contralateral side, most labelled ganglion cells were visible in the anteromedial part of the ophthalmic-maxillary region but a few could also be seen in the mandibular division. Their average diameter was 21.1 micron (s.d. = 5.5). No labelled ganglion cells were observed in adult rats subjected to the same series of manipulations. In a separate series of neonatally nerve-damaged animals, the above-described procedures were combined with neonatal injection of capsaicin in an effort to determine whether the observed sprouting was dependent upon the presence of large numbers of unmyelinated axons. The addition of this treatment reduced the number of labelled cells in both the ipsilateral and contralateral ganglia, but it did not alter either their distribution or average soma diameter. In a final experiment, sequential double-labelling techniques were used to determine whether the V axons that projected to the vibrissa pad via non-IO nerve branches were the result of sprouting by undamaged ganglion cells or arose from neurons that had originally projected into the IO nerve, were axotomized by our lesions, and regenerated to the vibrissa pad via another V branch. Here, the long-lived retrograde tracer true blue (TB) was injected into the vibrissa pad 6-8 hours before the neonatal nerve cut and DY was deposited into the pad after transection of the regenerate IO nerve in adulthood. Double-labelled cells in this experiment would have projected to the vibrissa pad via the IO nerve at birth and regenerated to it via another V branch in adulthood. Nearly 55% of the DY-labelled cells in this experiment also contained TB.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1988

Nalbuphine analgesia in the prehospital setting.

Forty-six patients with moderate to severe pain caused by orthopedic injuries, burns, multiple trauma, or intraabdominal conditions were treated with intravenous (IV) nalbuphine hydrochloride (Nubain; DuPont Pharmaceuticals, Wilmington, DE) by paramedics before arrival at the hospital. Patients who weighed less than 60 kg received 15 mg nalbuphine, and patients weighing greater than 60 kg received 20 mg nalbuphine. Forty-one of 46 patients (89%) experienced pain relief from nalbuphine, with maximum relief occurring within 15 minutes after the administration of the drug. Two addicted patients received no pain relief. There were no untoward side effects following nalbuphine administration, and the patients' heart rates, mean arterial pressures, and respiratory rates remained constant and stable throughout the study period. Repeated assessment of the patient by paramedics in the field was not impaired by nalbuphine treatment. In summary, nalbuphine hydrochloride is a useful and safe analgesic drug for IV use by paramedics in the prehospital setting.

Adolescent↗
PubMed1987

Cloned, Ia-restricted T cells that do not produce interleukin 4(IL 4)/B cell stimulatory factor 1(BSF-1) fail to help antigen-specific B cells.

T cells can be subdivided based on cell surface markers, MHC restriction, function, and production of soluble factors. Analysis of the ability of cloned, Ia-restricted, L3T4+ T cells to induce an in vitro anti-hapten antibody response to hapten-carrier conjugates allowed the definition of three functional subtypes. To examine whether these functional subtypes also differed in the production of soluble mediators, supernatants of the cloned lines were examined for the production of T cell growth factors and factors inducing increased expression of Ia glycoproteins on small resting B cells. All of the cloned lines produced T cell growth factors that could be further differentiated by inhibition with monoclonal antibodies. None of the Ia-restricted, L3T4+ cloned T cell lines that failed to produce IL 4/BSF-1 could provide helper function. Thus, the activation of antigen-specific B cells by helper T cells appears to require IL 4/BSF-1 as a necessary but not sufficient signal for differentiation into antibody-forming cells.

Animals↗
PubMed1987

Orbital optic glioma in neurofibromatosis. Magnetic resonance diagnosis of perineural arachnoidal gliomatosis.

In a patient with neurofibromatosis and orbital optic glioma, T2-weighted axial magnetic resonance images showed a fusiform area of high signal intensity with a central linear core of lower signal intensity. Computed tomographic images did not show a corresponding variation in tumor density. Histopathologic examination of the tumor revealed dense, circumferential, perineural glial proliferation. This "arachnoidal gliomatosis" is a feature of orbital optic gliomas in neurofibromatosis and, in our magnetic resonance scans, accurately corresponded with the region of high signal intensity within the tumor.

Arachnoid↗