Membrane phenotype and response to deoxycoformycin in mature T cell malignancies

The adenosine deaminase inhibitor deoxycoformycin was used in low doses to treat 19 patients with clinically aggressive T cell malignancy with a mature membrane phenotype. The patients comprised eight with prolymphocytic leukaemia, two with chronic lymphocytic leukaemia, four with adult T cell leukaemia-lymphoma, three with Sézary syndrome, and two with T cell lymphoma. Two thirds of the patients had been resistant or minimally responsive to combination chemotherapy. Complete remission was obtained in five patients (two with prolymphocytic leukaemia and one each with chronic lymphocytic leukaemia, adult T cell leukaemia-lymphoma, and Sézary syndrome) and partial remission in two others. Unmaintained complete remission lasting more than one year was seen in three patients. Responses were obtained only in patients with CD4+,CD8-membrane markers (seven out of 10), and no responses were recorded in any of the nine patients with a different phenotype. In this series remission appeared to correlate with the membrane phenotype of the neoplastic cell and not with the cytopathological diagnosis. Future studies should establish the biochemical basis for the greater sensitivity of CD4+ lymphoid cells to deoxycoformycin.     

Sinonasal undifferentiated carcinoma. An aggressive neoplasm derived from schneiderian epithelium and distinct from olfactory neuroblastoma

Eight cases of a highly aggressive undifferentiated carcinoma of the nasal cavity and paranasal sinuses are described. The patients, who ranged in age from 30-77 years, had multiple sinonasal symptoms, and each had involvement of the nasal cavity, maxillary antrum, and ethmoid sinus. Six tumors extended into the orbital bones, and five penetrated the cranial cavity. Five patients died of disease from 1 to 41 months after diagnosis (median: 4 months), and three are alive with tumor less than 1 year following diagnosis. Microscopically, the neoplasms formed nests, trabeculae, and sheets containing medium-sized cells with small to moderate amounts of eosinophilic cytoplasm. A high mitotic rate, tumor necrosis, and prominent vascular permeation were characteristic. Seven neoplasms were immunoreactive for cytokeratin, five for epithelial membrane antigen, and four for neuron-specific enolase. Ultrastructurally, occasional small desmosomes and rare membrane-bound, dense-core granules were observed. Sinonasal undifferentiated carcinoma is a distinctive clinicopathologic entity that must be distinguished from other, less aggressive sinonasal neoplasms.     

Distinctive immunoglobulin E anti-house dust allergen-binding specificities in a tropical Australian Aboriginal community

BACKGROUND: There is evidence that the specificity of the IgE binding in allergy tests can vary for different populations. OBJECTIVE: We aimed to examine the allergenic specificity of IgE binding in sera from house dust mite (HDM)-atopic subjects in a tropical Australian Aboriginal community. METHODS: Sera shown to contain IgE antibodies to an HDM extract of Dermatophagoides pteronyssinus were examined for IgE binding to a panel of nine purified HDM allergens from this mite species by quantitative microtitre assays. IgG antibody binding (IgG1 and IgG4) was also measured. RESULTS: The IgE-binding activity in the sera from the Aboriginal community was not directed to the expected major groups 1 and 2 HDM allergens but instead to the group 4 amylase allergen. There was also little IgE binding to the potentially cross-reactive tropomyosin (Der p 10) or arginine kinase (Der p 20) allergens. The IgG4 antibody was rarely detected and limited to the Der p 4 allergen. IgG1 antibody binding was frequently measured to all the allergens regardless of an individual's atopic status, whereas in urban communities it is restricted to the major allergens and to atopic subjects. CONCLUSION: The high IgE anti-HDM response of Australian Aboriginals predominantly bound Der p 4 and not the Der p 1 and 2 allergens, showing a distinctive allergy that could affect the disease outcome and diagnosis.     

The black hole effect in perimetry

Light-emitting diodes (LEDs), mounted in drilled holes in the perimeter bowl, are used as stimuli in several automated perimeters. A concern is that these "black holes" might interrupt the otherwise uniform background illumination and cause inconsistent test results. A Dicon perimeter was modified by covering some of the LEDs with diffusing plastic. One eye of 41 normal volunteers was tested repetitively within the central 5 degrees of the visual field at the same 12 locations with both covered and uncovered LED stimuli. Higher variances of multiple threshold determinations were observed, significant at the 0.0005 level, when testing was done with uncovered LEDs. On average, the black hole effect contributed 0.8 dB to short-term fluctuation. The black hole effect is probably of minor clinical importance except in exacting quantitative perimetry.     

Preparation of the internal mammary artery graft. Which is the best method?

Early reports questioned the adequacy of flow of the internal mammary artery when used routinely as a bypass graft. "Adequate" mammary artery flow is now contested only in certain situations, that is, left ventricular hypertrophy, acute myocardial infarction, and reoperations. To compare the methods of mammary pedicle graft preparations with free mammary artery flow, we studied 31 patients who had the left internal mammary artery harvested for elective coronary artery bypass grafting. Group I comprised 14 patients whose mean body surface area was 1.91 m2. Systolic, diastolic, and mean arterial blood pressures, left atrial pressure, and heart rate were recorded and stabilized during flow measurements. Free flow of the internal mammary artery was measured before any pharmacologic manipulation and ranged from 5 to 44 ml/min (mean 18 ml/min). The grafts were sprayed and wrapped in sponges soaked in diluted papaverine solution (60 mg in 40 ml normal saline) for an average of 21 minutes. Free flow ranged from 10 to 108 ml/min (mean 51 ml/min). Intraluminal papaverine of the same dilution was then injected with hydrostatic dilatation. Immediate internal mammary artery flows rose from 150 to 333 ml/min (mean 229 ml/min). Group II comprised 17 patients who had internal mammary artery takedown under the exact conditions used in group I. Mean body surface area was 1.89 m2. Mammary artery pedicles were injected with diluted papaverine throughout their lengths with size 25 needles. After an average of 19.5 minutes, free flow ranged from 28 to 132 ml/min (mean 69 ml/min). Intraluminal diluted papaverine was then administered as in group I, and flows increased from 144 to 280 ml/min (mean 198 ml/min). The distal internal mammary arteries in both groups were 1.75 to 2.5 mm in internal diameter at the site of arteriotomy for flow measurement. This study shows that all mammary arteries are in spasm immediately after harvest and that flow is inadequate before any pharmacologic intervention. Although extraluminal vasodilators will increase free mammary artery flow, intraluminal papaverine followed by hydrostatic dilatation raises free flow to maximal capacity. Subsequent graft spasm has not been observed.(ABSTRACT TRUNCATED AT 400 WORDS)     

Bone mineral density in relation to medical and lifestyle risk factors for osteoporosis in premenopausal, menopausal and postmenopausal women in general practice.

BACKGROUND. Interest in the prevention of osteoporosis is increasing and thus there is a need for an acceptable osteoporosis prevention programme in general practice. AIM. A study was undertaken to identify a cohort of middle-aged women attending a general practice who would be eligible for a longitudinal study looking at bone mineral density, osteoporosis and the effectiveness of hormone replacement therapy. This study aimed to describe the relationship between medical and lifestyle risk factors for osteoporosis and the initial bone density measurements in this group of women. METHOD. A health visitor administered a questionnaire to women aged between 48 and 52 years registered with a Belfast general practice. The main outcome measures were menopausal status, presence of medical and lifestyle risk factors and bone mineral density measurements. RESULTS. A total of 358 women our of 472 (76%) took part in the study which was conducted in 1991 and 1992. A highly significant difference was found between the mean bone mineral density of premenopausal, menopausal and postmenopausal women within the narrow study age range, postmenopausal women having the lowest bone mineral density. A significant relationship was found between body mass index and bone mineral density, a greater bone mineral density being found among women with a higher body mass index. Risk factors such as smoking and sedentary lifestyle were common (reported by approximately one third of respondents) but a poor relationship was found between these two and all the other risk factors and bone mineral density in this age group. CONCLUSION. Risk of osteoporosis cannot be identified by the presence of risk factors in women aged between 48 and 52 years. In terms of a current prevention strategy for general practice it would be better to take a population-based approach except for those women known to be at high risk of osteoporosis: women with early menopause or those who have had an oophorectomy.