Contact angles of substances used for internal tamponade in retinal detachment surgery

In order to ascertain the tamponade effect of air and silicone oil we examined the contact angles subtended by ex vivo human retina, Teflon and Perspex to find a suitable experimental material which would mimic the surface properties of the retina at a three-phase interface. Using the captive bubble technique to measure the contact angle, it was found that air subtended a larger contact angle (38.8°) with the retina than did silicone oil (18.2°). On coating the Perspex surface with protein (PCP), it was observed that the surface properties were modified such that PCP subtended contact angles with air (43.0°) and silicone oil (16.4°) similar to those subtended by ex vivo human retina. Using PCP as an experimental material that mimics ex vivo human retina, spherical chambers were employed in order to examine qualitatively and to quantify the arc of contact obtained with air and silicone oil. It was found that air gave a greater arc of contact for the same percentage fill than silicone oil.     

Reliability of dual diagnosis. Substance dependence and psychiatric disorders.

The Structured Clinical Interview for DSM-III-R was used to examine the effects of the co-occurrence of psychiatric and substance dependence disorders on diagnostic reliability. The test-retest reliability over a 1-week period was studied in groups of: a) individuals with current substance abuse diagnoses (N = 97), b) individuals with past, but not current, drug histories (N = 146), and c) individuals without substance abuse diagnoses (N = 356; primarily psychiatric patients). A measurement of reliability (Kappa coefficients) was estimated for four general psychiatric categories (psychotic, mood, anxiety, and eating disorders), along with specific most-frequent diagnoses in each category (schizophrenia, major depression, panic disorders, and bulimia nervosa, respectively). Past use and non-drug-use groups were similar in their generally reliable reporting of current and past psychiatric disorders. However, current mood and psychotic disorders were less reliably diagnosed in the group with current substance use disorders.     

Fasting insulin and left ventricular mass in hypertensives and normotensive controls.

The mechanism by which increased left ventricular (LV) mass leads to increased coronary heart disease morbidity and mortality is unknown. We evaluated the relation between fasting insulin and echocardiographic LV mass in hypertensives off medication and normotensive controls, controlling the analyses for blood pressure (BP) and body mass index (BMI). Fasting insulin (p = 0.0217) was the most significant predictor of LV mass in hypertensives, while BMI (p = 0.0265) and diastolic BP (p = 0.0159) were the only significant predictors of LV mass in controls. The relation between fasting insulin and LV mass was not confounded by obesity in hypertensives, but obesity and fasting insulin may interact to predict LV mass.     

Value of acute-phase angiography in the detection of vascular injuries caused by gunshot wounds to the head: analysis of 12 cases.

A study of the angiographic findings in consecutive civilian patients with cranial gunshot wounds examined in the acute stage has not been done. Most prior clinical studies have evaluated the findings in survivors in the subacute or chronic stages and have often been of war-time casualties. We determined the clinicoradiologic features of six cases of posttraumatic intracranial aneurysm, vascular occlusion, or arteriovenous fistula caused by penetrating missiles among 12 civilian patients who were examined in the acute posttraumatic stage (within 48 hr of injury) during a 1-year period. Three internal carotid/vertebral artery aneurysms, one external carotid artery aneurysm, one combined aneurysm/arteriovenous fistula of the vertebrobasilar circulation, and one cerebral venous occlusion were identified. The 50% overall prevalence of major vascular lesions in this series of civilian patients with penetrating missile injuries examined in the acute stage suggests these injuries are more common than previously suspected. It may indicate that selective cerebral angiography should be considered in the evaluation of the cranial vascular system of such persons.     

New monoclonal antibodies reacting with bile ducts: further insights into the pathogenesis of bile ductular proliferation in biliary diseases.

We have produced a range of monoclonal antibodies which stain human intrahepatic bile ducts of different sizes. Amongst 26 monoclonal antibodies produced, five clones reacted specifically with bile ducts of different sizes, of which three have been maintained in culture and their viability following freezing and thawing confirmed. Staining patterns varied between normal adult liver tissue, normal fetal liver tissue and a variety of hepatobiliary diseases. The antibodies provide further evidence of the immunological heterogeneity of the human intrahepatic biliary tree and support the hypothesis that proliferating bile ductules are derived from periseptal hepatocytes. The preparation of the antibodies, their staining reactions in normal adult, normal fetal and a variety of liver diseases are described.     

High-Temperature Short-Time Heat Inactivation of HIV and Other Viruses in Human Blood Plasma

An ultra-short-time heating system was used to process blood plasma spiked with various viruses (HIV, vesicular stomatitis virus, encephalomyocarditis virus). Virus reduction and recovery of plasma proteins were measured at various temperatures from 65 to 85 degrees C. Processing at 77 degrees C and 0.006 s resulted in a high level of virus kill, including greater than or equal to 4.4 log10 HIV, while maintaining protein structure and activity essentially intact.     

The management of patients with an intrinsic supratentorial brain tumour

The management of patients presenting with supratentorial glioma between 1978 and 1986 is reviewed. Complete follow-up in 517 cases was obtained. One hundred and fifty eight patients were not submitted to any form of surgery, 299 patients were biopsied and 60 patients underwent craniotomy and internal decompression. The no surgery group contained a higher proportion of patients with poor prognostic indicators than either the biopsy or craniotomy groups. The craniotomy group consisted of patients with better prognostic indicators than the biopsy group, in particular, younger age and more favourable site, type and grade of tumour. This was reflected in the difference in outcome between the groups. Median survival was 14 months in the craniotomy group, four months in the biopsy group and 2.2 months in the no surgery group. The outcome in patients with histologically proven malignant gliomas was best in those patients who received radiotherapy. The craniotomy group had a median survival of 18.5 months, a two year survival of 48% and a five year survival of 9%. The median survival following radiotherapy of those patients with proven malignant gliomas who had a biopsy was 9.5 months with a two year survival of 16% and a five year survival of 2%. These results compare favourably with studies which have adopted a more aggressive approach, suggesting that outcome is determined as much by patient selection using favourable prognostic indicators as by the treatment itself. The need for prospective trials of the management of unselected consecutive glioma patients randomizing them to conservative and radical treatment groups in order to define the role of both conventional therapy and radical therapy is discussed.     

Urothelial grafts in mice

Mouse bladder epithelium has been successfully transplanted to the bladders of syngeneic mice and has survived for at least twenty weeks. The fate of the transplanted tissue was followed using a fluorescein label. The recipient bladders were prepared by stripping the urothelium either by a surgical or a chemical method. The possibility of adopting a comparable technique for the treatment of early bladder cancer in man is discussed.