Search PubMed⌕ Search

Biomedical subjects

M Whitehead

Publications and source records attributed to M Whitehead.

At least 55 records · Page 3Linked to original sources
PubMed1998

Effects of hormone replacement therapy on the endometrium and lipid parameters: a review of randomized clinical trials, 1985 to 1995.

The association between unopposed estrogen replacement therapy and endometrial hyperplasia and endometrial cancer in nonhysterectomized postmenopausal women is well known, and studies have suggested that the addition of progestin to the regimen reduces the risk of hyperplasia and cancer. The effect of estrogen plus progestin hormone replacement therapy on the lipid profile has also been extensively studied. To determine the extent of the effects of hormone replacement therapy on the endometrium and lipid parameters and to provide an overview of these studies, we reviewed 10 years of English language publications.

Endometrial Hyperplasia↗
PubMed1998

Diffusion of ideas on social inequalities in health: a European perspective.

The issue of social inequalities in health has become politically salient during the 1990s in many European countries. Research evidence and ideas that eventually came to the attention of national policy makers helped to trigger this change. The pathways of this information flow are traced through an examination of the work of international agencies and a presentation of case studies from three countries: the Netherlands, Britain, and Sweden. Each country's experience was different but nevertheless influenced and reinforced the courses of action adopted by the others. It is clear that, in order to meet the challenge that health inequalities pose to public health and policy, cooperation will become even more important in the future.

Diffusion of Innovation↗
PubMed1997

Venous thrombo-embolism and hormone replacement therapy.

Recent data have indicated that hormone replacement therapy (HRT) is associated with an increased risk of venous thrombo-embolism. Although the relative risk is significantly higher, the absolute risk remains small. Epidemiological studies on which the increased risk was based may have been open to biases, including those of referral, investigation and diagnosis. None the less, the association appears real albeit the mechanism poorly understood. Potential mechanisms include unmasking of an underlying thrombophilia or combination with other recognized risk factors for venous thrombo-embolism. The implications of these findings have to be placed firmly in the clinical context and weighed against the established benefits of hormone replacement therapy, including relief of menopausal symptoms, prevention of osteoporosis and arterial-vascular disease. Patients with a personal or family history of venous thrombo-embolism should be screened for underlying thrombophilia and such screening may be extended to relatives. However, the risk of venous thrombo-embolism following initiation of HRT is not yet known. None the less, HRT should be used with caution in this situation and may be best avoided, unless associated with concomitant antithrombotic therapy, in certain thrombophilias, expert advice should be sought. Patients without risk factors should be advised of the small increase in risk of venous thrombosis which is greatest during the first year. Where additional risk factors are present the situation will have to be assessed on an individual basis for each patient. For example, the beneficial effects of HRT in an obese patient at risk of arterial disease may outweigh the small risk of thrombosis. Patients already on HRT should have some assessment of the risk of venous thrombosis made and where there are features suggestive of thrombophilia screening performed.

Estrogen Replacement Therapy↗
PubMed1997

Quality of life scores: an independent prognostic variable in a general population of cancer patients receiving chemotherapy. The National Cancer Institute of Canada Clinical Trials Group.

This report examines the prognostic associations between QOL scores measured by the EORTC QLQ-C30 and survival in a large heterogeneous population of cancer patients. Eight hundred and fifty-one cancer patients who were to receive chemotherapy were enrolled in two National Cancer Institute of Canada Clinical Trials Group (NCIC CTG) antiemetic trials. All patients completed the EORTC QLQ-C30 immediately prior to their first chemotherapy. Survival data were available and obtained for 474 of 639 patients (74%). Cox's proportional hazards model was used to assess the independent impact of QOL and demographic variables on survival. Presence of metastatic disease, diagnosis of lung or ovarian cancer, ECOG performance status, global quality of life and emotional functioning were significantly associated with survival. Global QOL was predictive in all patients, in subgroups of patients with metastatic disease, with breast and lung cancer and other tumour types. In patients with low global quality of life scores, patients with low emotional functioning ratings lived longer than did patients with high emotional functioning ratings. Patients with high global QOL live significantly longer than do patients with low global QOL. The relationship between emotional functioning in patients with low global QOL and survival needs confirmation.

Female↗
PubMed1996

Pressure-limited ventilation with permissive hypercapnia and minimum PEEP in saline-lavaged rabbits allows progressive improvement in oxygenation, but does not avoid ventilator-induced lung injury.

OBJECTIVE: To determine whether pressure-limited intermittent mandatory ventilation with permissive hypercapnia and positive end-expiratory pressure (PEEP) titrated to arterial oxygen tension (PaO2) prevents or reduces acute lung injury, compared to conventional ventilation, in saline-lavaged rabbits. DESIGN: Prospective randomised trial. SETTING: University animal laboratory. SUBJECTS: 18 New Zealand White rabbits. INTERVENTIONS: Following five sequential saline lung lavages, anaesthetised rabbits were randomly allocated in pairs to receive either of two ventilation protocols using intermittent mandatory ventilation. The study group had peak inspiratory pressure limited to 15 cm H2O and arterial partial pressure of carbon dioxide (PaCO2) was allowed to rise. The control group received 12 ml/kg tidal volume with rate adjusted for normocarbia. PEEP and fractional inspired oxygen (FIO2) were adjusted to maintain, PaO2 between 8 and 13.3 kPa (60 and 100 mm Hg) using a predetermined protocol. At 10 h or following death, lung lavage was repeated and lung histology evaluated. MEASUREMENTS AND MAIN RESULTS: The mean increase in lavage cell counts and protein concentration and hyaline membrane scores were not significantly different between the groups. Oxygenation progressively improved more in the study group (p = 0.01 vs control for PaO2/FIO2 ratio and alveolar-arterial oxygen tension gradient (AaDO2)). PEEP was similar and the mean airway pressure higher in the control group, suggesting that this probably resulted from less ventilator-induced injury in the study group. Four deaths occurred in the control group (three due to pneumothorax and one to hypoxaemia) and none in the study group (p = 0.08). CONCLUSIONS: This ventilatory protocol may have failed to prevent lung overdistension or it may have provided insufficient PEEP to prevent injury in this model; PEEP greater than the lower inflection point of the pressure-volume curve has been shown to prevent injury almost entirely.

Animals↗
PubMed1996

Treatments for menopausal and post-menopausal problems: present and future.

Probable developments in HRT and non-HRT treatments for menopausal and post-menopausal problems have been reviewed. More information is required on potential benefits and side-effects of HRT. The major potential benefit is prevention against stroke amelioration of Alzheimer's disease: the major potential side-effect discussed in this chapter is ovarian cancer. At present, techniques for delivering oestrogens are more varied and advanced than those for progestogens. Non-oral delivery systems for progestogens which minimize side-effects will be introduced during the next decade. It is not clear whether benefits expected with new progestational agents will be realized. Preliminary data suggest that SERMs and phytoestrogens are worthy of further evaluation. Their development will provoke intense interest over the next 10 years.

Aged↗
PubMed1996

Current patterns and trends in male mortality by social class (based on occupation).

Every ten years, information from the decennial census is used together with national death registration data to study socio-economic differences in mortality. This article reports the findings of one of the analyses prepared for the latest decennial supplement. This volume is due for publication late in 1997. Over 175,000 deaths of men aged 20-64 in England and Wales were analysed using the Registrar General's Social Class (based on occupation) schema. The social gradient in all-cause mortality observed in earlier decades is still seen in 1991-93. In absolute terms, there has been a fall in mortality rates in England and Wales over the twenty-year period 1970-72 to 1991-93. This is reflected in the falls in mortality rates for each of the social classes I to IV over the two decades. In contrast, the mortality rate of Social Class V rose in the early 1980s. Since then, it has fallen. However, it is still higher than in the early 1970s. Trends in mortality show a relative widening of social differentials developing over this period. This is true for all-cause mortality and for the specific causes investigated in this article. Mortality is almost three times higher in Social Class V (SMR 189) than in Social Class I (SMR 66). Classes IIIM and IV (SMRs 117, 116 respectively) have nearly double the mortality of Class I. Even larger differentials are observed for stroke, lung cancer and suicide.

Adult↗
PubMed1995

Posterior fontanelle cranial ultrasound: anatomic and sonographic correlation.

OBJECTIVE: The purpose of this study was to correlate normal brain anatomy as seen on posterior fontanelle cranial sonography with anatomical sections of the premature infant brain. MATERIALS AND METHODS: Images obtained from 93 cranial ultrasound examinations performed via both the anterior and posterior fontanelle in 53 infants, ranging in gestational age from 24 to 42 weeks, were reviewed to determine the ultrasound anatomy visible and also the changing appearances with increasing gestational age. The brains of five infants were sectioned at post-mortem according to predetermined anatomical landmarks to correlate with posterior fontanelle ultrasound scan planes. Brain preservation techniques involved fixation in formalin at room temperature, refrigeration of brain following formalin fixation, and brain freezing at -17 degrees C. RESULTS: In the premature infant brain, the subarachnoid space is up to 15 mm in thickness. Occipital lobe anatomy well seen includes occipital horns of lateral ventricles, and white matter tracts to the visual cortex and visual association areas. Brain anatomy was better appreciated on sections obtained following brain freezing rather than formalin fixation. CONCLUSION: Satisfactory ultrasound anatomic correlation of the premature brain is possible using a brain freezing preservation technique. Posterior fontanelle ultrasound allows detailed illustration of occipital lobe anatomy.

Brain↗