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D McManus

Publications and source records attributed to D McManus.

17 recordsLinked to original sources

First clinical case of small de novo duplication of 19q (13.3-13.4) confirmed by FISH.

Partial trisomy of 19q has been reported in only 13 patients, of which all but one have been due to unbalanced translocations. Only one previous report of a de novo duplication of distal 19q has been described in a fetal chorionic villus sample. There was no description of clinical phenotype in this report. We describe the clinical manifestations and cytogenetic analysis in a child with an inverted duplication of 19q 13.3 to 13.4 confirmed by FISH using a chromosome 19 whole chromosome probe. This case represents the first report of a liveborn with "pure" distal trisomy 19q. Findings defining this uncommon aneusomy are a flat facies, down turned mouth, abnormal ears, and a short neck with redundant skin folds.

Abnormalities, Multiple↗

Regional variations in endothelin-1 and its receptor subtypes in human coronary vasculature: pathophysiological implications in coronary disease.

Endothelin-1 is a potent vasoconstrictor peptide and mitogen for vascular smooth muscle cells. Increased plasma or tissue levels of endothelin-1 have been described after myocardial infarction and in atherosclerosis, suggesting that this peptide may play a pathophysiological role in various coronary syndromes. Here, we have studied regional variations in ET-1 and its receptors in control and atherosclerotic human coronary vasculature using standard immunohistochemistry and in vitro autoradiography. ET-1 immunoreactivity was associated with luminal endothelial cells and smooth muscle cells at regions of atherosclerosis. ET(A) receptors were present on smooth muscle cells of coronary arteries and on cardiac myocytes. Medial ET(B) receptor binding at the proximal region of coronary arteries was weak, but increased significantly towards distal regions of this vessel (p<0.005 in control and p<0.0005 in ischaemic heart disease). Microvascular endothelial cells in the adventitia of coronary arteries, myocardial microvessels and the endocardial endothelium expressed the ET(B) receptor exclusively. The receptor variations revealed in this study provide supporting evidence that ET-1 is associated with (1) vascular smooth muscle and endothelial cell proliferation, including areas of intimal hyperplasia and regions of neovascularization (2) increased ET-1-induced reactivity of distal portions of the human coronary artery, (3) ET-1-mediated constriction of myocardial microvessels. These results provide new insights into different potential roles for this peptide in healthy and diseased human coronary vasculature.

Autoradiography↗

T-cell-rich histiocyte-rich B-cell lymphoma of parotid gland.

We describe a malignant lymphoma of the parotid gland arising in a patient with Sjögren's syndrome. Diagnosis was established on needle biopsy which showed a mixed population of lymphoid cells. Immunohistochemistry revealed B-lymphoid cells, T-lymphoid cells and histiocytes. Clonal immunoglobulin heavy chain gene rearrangement was demonstrated using the polymerase chain reaction. Within the confines of the small biopsy, the lesion qualifies for the designation T-cell-rich histiocyte-rich B-cell lymphoma. The value of molecular techniques in the diagnosis of malignant lymphoma on limited tissue samples is highlighted by this case.

Aged↗

Can practicing physicians improve their counseling and physical examination skills in breast cancer screening? A feasibility study.

OBJECTIVE: To improve breast cancer screening skills, practicing non-academic primary care physicians were offered an opportunity to participate in a one-hour private skills-assessment session with a patient instructor. Research questions included: would physicians in non-academic practice be interested in a skills course; would the course improve their skills in breast examination and/or in counseling for mammography; and if they did improve, would the effect endure? DESIGN: Pilot study with cohort follow-up. INTERVENTIONS: Physicians were offered an opportunity to have their counseling and physical examination skills evaluated in a one-on-one interaction with standardized patients. The protocol included patient instructors who were trained to use a uniform breast health history that emphasized their increased risk of breast cancer, scant knowledge of breast-cancer screening, and fear of medical tests and cancer. The standardized patients were trained using a 77-point checklist. They demonstrated a high degree of consistency and reproducibility. A critical part of the learning experience was immediate feedback to the physicians regarding their performances. Physicians who took the course were given an opportunity to repeat it approximately 18 months later. MEASUREMENTS AND MAIN RESULTS: Of the 82 primary care physicians in the community, 49 (60%) were eligible to have their skills evaluated. Of these, 38 (77.6%) participated in the intervention. Baseline skills had mean scores (correct responses) better than 50% in most aspects of the physical examination but less than 35% in several critical counseling areas: reviewing mechanics of getting mammography, actually recommending mammography, and directing the patient regarding scheduling. Of the 38 physicians, 15 repeated the course. There was a significant improvement in their overall performance: 49% vs 67% (p = 0.002). CONCLUSIONS: Primary care physicians in a non-academic practice are interested in reviewing and improving their counseling skills. They are capable of improving their skills after receiving background information, instruction, and brief feedback. They maintain these improvements over time.

Breast Neoplasms↗

Hydatid disease.

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Animals↗

Probucol and other antioxidants prevent the inhibition of endothelium-dependent relaxation by low density lipoproteins.

Hypercholesterolaemia and atherosclerosis impair responses to endothelium-derived nitric oxide (EDRF) in human and animal coronary arteries, a dysfunction that correlates with elevated low density lipoproteins (LDL). Previous studies show that native LDL immediately and reversibly inhibit acetylcholine-evoked EDRF responses in rabbit aortic ring precontracted with noradrenaline or serotonin whereas Cu(2+)-oxidised LDL (oxLDL) inhibit relaxations after 30 min with a potency that varies with the donor. We now show that antioxidants, probucol (10 microM) and ascorbic acid (100 microM) in vitro, prevent the inhibition by native LDL, indicating that this effect involves free radicals. As expected, the antioxidants had no influence on the inhibition by oxLDL. Superoxide dismutase appeared to have no effect on the inhibition by native or oxLDL. The oral administration of probucol to selected volunteers also prevented the inhibition of relaxation by their native LDL. These preparations showed a diminished susceptibility to oxidation and their oxLDL caused a markedly reduced and always reversible inhibition of relaxation compared to the potent and sometimes irreversible inhibition prior to administration of the drug. We conclude that antioxidants such as probucol reduce the formation of free radicals and the oxidative modification of LDL that lead to the impairment of EDRF responses and may prevent this same dysfunction in hypercholesterolaemia and atherosclerosis.

Acetylcholine↗

MRI in schizophrenia: basal ganglia and white matter T1 times.

The T1 relaxation time of the basal ganglia (putamen, globus pallidus and head of caudate) and of the frontoparietal centrum semiovale was compared between 49 schizophrenic patients and 36 healthy controls. Previous reports of increased T1 time in the basal ganglia were not confirmed, and group differences were not detected within the white matter. Within patients T1 values could not be related to tardive dyskinesia or other clinical features. Normal variation seen in basal ganglia T1 times is described for the first time: lowest values occur in the globus pallidus and highest in the caudate, and values within the putamen increase rostrally.

Adult↗

Individual differences in cognitive processes: towards an explanation of schizophrenic symptomatology.

A study is reported that examined the relationship between a measure of schizophrenic-like characteristics (schizotypy) in normal subjects and cognitive inhibition. Both repetitive and semantic measures of priming were used. It was found that low schizotypes showed negative priming (i.e. longer reaction times to the re-presentation of initially ignored stimuli) while high schizotypes did not; high schizotypes exhibited semantic facilitation (i.e. shorter reaction times to previously ignored stimuli) but low schizotypes did not. A model is suggested, including both inhibitory and facilitatory processes, which can account for these findings. Theorizing about these processes is of interest as it may shed some light on the mechanisms involved in the specifically cognitive symptoms of schizophrenia.

Adolescent↗