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Biomedical subjects

J Marshall

Publications and source records attributed to J Marshall.

At least 451 records · Page 25Linked to original sources
PubMed1984

An automatic electronic device (Rite Time) to detect the onset of the infertile period by basal body temperature measurements.

Two trials of an electronic thermometer (Rite Time), designed to record and interpret basal body temperature (BBT) patterns in normal ovulating women, are described. A total of 140 menstrual cycles from 34 women, who used the thermal or symptothermal methods of natural family planning, were studied. Rite Time gave a signal for the start of the infertile period in 117 cycles, of which 114 (97%) appeared to have occurred at appropriate times. Further studies using hormonal and ultrasound reference points for ovulation were carried out in 21 cycles. Rite Time generally produced BBT patterns of quality acceptable for interpretation of the periovulatory BBT shift. About one-half of the volunteers said that they would be willing to replace their conventional charting methods with Rite Time.

Body Temperature↗
PubMed1984

Retinal and epiretinal glia--an immunohistochemical study.

Immunohistochemical techniques were used to examine the distribution of cells containing glial fibrillary acidic protein (GFAP) in normal and pathological human specimens, including 22 globes (13 of which contained epiretinal membranes 'in situ'), 16 surgically excised epiretinal membranes, and monolayers of cells obtained from five epiretinal membranes placed in tissue culture. The astrocytic cells of normal and pathological retinae stained with the glial-cell marker, but Müller cells were GFAP-negative in normal retinae at the antisera dilutions used. Müller cells did, however, stain in retinae from glaucomatous eyes and in eyes with prolonged retinal detachment. Electron microscopy did not reveal any obvious morphological difference between the intermediate filaments of normal (GFAP-negative) and GFAP-positive Müller cells. Ten of the 13 epiretinal membranes 'in situ', all 16 excised membranes, and three of the five monolayers contained glial cells. Purely glial membranes were not associated with retinal puckering or detachment, while all membranes causing tractional complications had a prominent fibrous, non-glial component. Our findings suggest that glial cells do not contribute significantly to the contractile forces generated by epiretinal membranes. They may, however, provide a scaffold on which other cells proliferate and contract and an anchorage by means of which tangential forces are transmitted into and through the retina.

Adolescent↗
PubMed1984

Effect of indomethacin on cerebral blood flow, carbon dioxide reactivity and the response to epoprostenol (prostacyclin) infusion in man.

Cerebral blood flow (CBF) has been measured using a non-invasive Xenon133 clearance technique in six normal subjects after 2 days pretreatment with oral indomethacin at a dose of 100 mg/day. The results were compared with placebo given in a double blind balanced cross-over design. Indomethacin was found to result in a reduction in resting CBF of about 25% but the reactivity of the cerebrovascular circulation to carbon dioxide was preserved at normal levels. Infusions of epoprostenol (prostacyclin, PGI2) at a dose of 5 ng/kg/min resulted in a reduction of CBF of about 10% after placebo but no significant change in CBF after indomethacin. The results suggest that prostaglandins are involved in the maintenance of cerebrovascular tone but not in the mechanism of cerebral vasodilation accompanying hypercapnia. The combination of indomethacin and PGI2 has been proposed as a treatment of cerebral artery spasm and the findings suggest that the combination therapy would not be accompanied by undesirable intracerebral steal.

Adult↗
PubMed1984

Subarachnoid haemorrhage in identical twins.

A pair of identical twins both of whom died of subarachnoid haemorrhage from ruptured anterior communicating artery aneurysms are reported. These twins are compared to the three other reported twins with ruptured cerebral aneurysms.

Adult↗
PubMed1984

Studies on regional cerebral oxygen utilisation and cognitive function in multiple sclerosis.

Regional cerebral oxygen utilisation (rCMRO2), oxygen extraction (rOER), blood flow (rCBF), and blood volume (rCBV) have been determined for fifteen patients with multiple sclerosis in remission using positron emission tomography (PET). Cerebral oxygen utilisation and blood flow were significantly reduced in both white matter and peripheral cortical grey matter in the multiple sclerosis patients compared to a group of normal controls. No evidence of regional cerebral ischaemia in the multiple sclerosis group was found. Lowest levels of cerebral oxygen utilisation were found in patients with cerebral atrophy, and in patients in whom a significant fall in present full-scale IQ from estimated pre-morbid levels had occurred. No correlation was found between rCMRO2 values and severity of locomotor dysfunction or clinical disease duration.

Adult↗
PubMed1984

Cerebral blood flow after carotid occlusion and extracranial-intracranial bypass.

Eleven patients with occlusion of one internal carotid artery showed marked reduction of regional cerebral blood flow (rCBF) through the hemisphere on the affected side with high rCBF on the opposite side. Six of the patients had no surgery, during follow-up of 2 to 5 years. rCBF increased on both sides leaving a persisting asymmetry of rCBF. Five patients had extracranial-intracranial bypass; rCBF increased on the affected side but not on the opposite side. Asymmetry of rCBF between the hemispheres remained but was much less than in the non-operated group.

Adult↗
PubMed1984

Long survival in subacute sclerosing panencephalitis.

A case is reported of a boy who at the age of 14 years developed subacute sclerosing panencephalitis. He deteriorated over a period of 9 months, improved greatly and remained stable for 7 years before relapse. The final deterioration to death extended over 6 years. During the whole period he was examined regularly and the electroencephalogram recorded at 3 to 6 monthly intervals. The brain was examined histologically after death. Electroencephalographic and pathological features are described.

Adolescent↗
PubMed1984

Beak and feather dystrophy in wild sulphur-crested cockatoos (Cacatua galerita).

Three flocks of wild sulphur-crested cockatoos in southeastern Australia had a 10-20% prevalence of feather and beak deformities. In affected birds, the crest, tail, contour and down feathers were lost or reduced in length owing to a "pinching off" 0.5-1 cm above the skin. The underlying skin was discolored brown. Flight feathers appeared normal and could sustain flight. In mildly affected birds, only the crest and down feathers were involved. Histological examination of affected feathers showed necrosis of developing cells in their epidermal collars. The epidermis was moderately hyperplastic and contained numerous large macrophages, with large intracytoplasmic granules. Electron microscopic examination showed these granules to consist of regular lattices of 17-20-nm-diameter particles, resembling parvovirus particles. In some birds the upper beak was enlarged and had longitudinal cracks. Histological examination of the beak showed necrosis of its epidermis. It was concluded that a viral infection may have caused feather and beak dystrophy in these birds.

Animals↗
PubMed1983

Human trabecular meshwork in primary culture: a morphological and autoradiographic study.

The growth and behaviour of human trabecular meshwork cells in primary culture was studied by light microscopy, time-lapse cinephotomicrography, autoradiography and electron microscopy. In all 925 explants of trabecular tissue from 132 eyes (68 +/- 14 years) were set up, and 20% produced extensive monolayers. Failure to produce primary outgrowths did not increase substantially until the eyes were over 5 days post-mortem. The latent period prior to growth was anything from a few days to 4 weeks; only then did meshwork cells label with [3H]-thymidine. The cells which grew incorporated large amounts of [3H]-leucine and this served as a useful marker to identify migratory cells. In addition they had the ultrastructural features of metabolically active cells including many mitochondria, a well-developed Golgi apparatus, abundant rough endoplasmic reticulum and prominent lysosomes. It was considered that the cells in primary culture had many features in common with 'activated' rather than normal meshwork cells.

Adult↗
PubMed1983

The role of stress, social support and age in survival from breast cancer.

This study focused on the relationship of objective and subjective stresses to survival from breast cancer. The potential mediating roles of social support and age were also considered. This prospective study involved 208 white female breast cancer patients diagnosed between 1958 and 1960. At the time of diagnosis, subjects were interviewed regarding objective and subjective stress and social support present in the 5-year period preceding their diagnosis. Twenty years later, survival was calculated. The relationships between stress and survival were examined for three age groups: 15-45, 46-60, and 61 and older. Objective stress was related to survival for the oldest group while subjective stress was related to survival for the youngest group. Neither stress was related to survival for women aged 46-60. Social involvement was independently related to survival although it was not a mediator in the stress-survival relationship. Using the entire sample, stage of cancer at diagnosis was the best predictor of survival. However, when women aged 46-60 were eliminated from the analysis, stress and social involvement accounted for twice as much variance in survival as stage.

Adolescent↗
PubMed1983

Nuclear magnetic resonance imaging of the posterior fossa: 50 cases.

Fifty patients with clinical diagnoses of disease within the posterior fossa were examined with a nuclear magnetic resonance (NMR) scanner and the results were compared with X-ray computed tomography (CT). A variety of NMR pulse sequences reflecting proton density, T1, T2 and blood flow were used and imaging was performed in transverse coronal and sagittal planes. In many cases NMR provided diagnostic information unavailable from CT scans. This included recognition of lesions not seen with CT in infarction and multiple sclerosis, as well as more precise definition of mass effects, oedema and anatomical relationships in other diseases. Extrinsic and intrinsic tumours were readily distinguished, as were brain-stem and cerebellar tumours. Arnold-Chiari malformations were demonstrated with sagittal scans and cerebellar atrophy was identified. A patient treated with radiotherapy displayed more extensive changes in the surrounding brain with NMR than with CT. Evidence of occlusion or reduced flow was found in two cases with vertebro-basilar disease. Occlusion of the internal carotid artery was also demonstrated. Computed tomography was superior to NMR in demonstrating calcification and bone erosion. In four of 14 tumours studied, contrast-enhanced CT demonstrated the margin between tumour and surrounding oedema or brain better than NMR. Nuclear magnetic resonance imaging is a versatile, non-invasive technique capable of demonstrating a wide spectrum of disease within the posterior fossa.

Adolescent↗
PubMed1983

Police occupational demands, psychological distress and the coping function of alcohol.

Alcohol use is an important problem among personnel in the high-stress police occupation. The impact of occupational demands, psychological distress, and coping on police alcohol consumption are explored. Results indicate that psychological distress, as an intervening factor between work demands and alcohol use itself, has an important positive effect on alcohol use.

Alcohol Drinking↗
PubMed1983

Progressive leptomeningeal fibrosis: a clinico-pathological case report.

A female patient developed persistent facial pain beginning at age 19 years. Intermittent motor and sensory disturbances referable to one hemisphere began nine years later and by the age of 41 she had developed signs of increased intracranial pressure. Exploratory craniotomy revealed replacement of the leptomeninges by thick, fibrous tissue. The histological appearance was that of a chronic, benign and minimally infiltrative process with a mild, non-specific inflammatory component, underlying cortical ischaemic changes, and white matter oedema. The lesion resembled nodular fasciitis, a soft tissue process. No cause of the reactive fibrosis of the meninges in this case is known.

Adult↗
PubMed1983

The effect of glucocorticoid hormones on release of HBsAg from PLC/PRF/5 (Alexander) hepatoma cells.

The glucocorticoid hormones dexamethasone, beta-methasone, and cortisone enhanced HBsAg release from PLC/PRF/5 cells by 40 per cent, 40 per cent and 10 per cent respectively, as compared to untreated controls. In the same experiments dexamethasone and betamethasone depressed the viable cell population by 20 per cent compared to the controls whereas cortisone had no significant effect. Immune electron microscope studies of the HBsAg material revealed no morphological differences compared to the control. Thus the glucocorticoid hormones dexamethasone, betamethasone and cortisone induce quantitative enhancement of HBsAg release without significant qualitative change. It is suggested that quantitative change in HBsAg release relates at least in part to the cell cycle of PLC/PRF/5 cells.

Betamethasone↗
PubMed1983

Diet in the epidemiology of carcinoma of the prostate gland.

In vivo, in vitro, prospective, and retrospective epidemiologic inquiries have suggested that retinoids inhibit cancer, and fats have been hypothesized to enhance and ascorbic acid to reduce cancer risk. Comparison of 260 patients from Buffalo with cancer of the prostate gland was made with two different control series of similar size and age distribution. Regardless of the control group, risk of prostate cancer gained with increases in ingestion of retinoids, animal fats, and vitamin C. These anomalous findings may be due to peculiarities in methodology. From the possible specificity of effect of the nutrients studied, as shown in experimental animals and in vitro, a hypothesis could be made that a substance like vitamin A or C, which may inhibit certain cancers, also may enhance risk of other cancer types or have neither effect.

Adult↗