Chromosomal breakage analysis in dyskeratosis congenita peripheral blood lymphocytes.

Dyskeratosis congenita (DC) is a rare inherited disorder characterized by reticulate skin pigmentation, nail dystrophy and mucosal leucoplakia. Bone marrow failure occurs in the majority of cases and there is a predisposition to malignancy. Following conflicting reports of increased spontaneous and induced chromosomal breakage in DC lymphocytes, we examined chromosomal breakage with and without clastogen treatment in 10 DC patients from six different families.

Fas-independent death of activated CD4(+) T lymphocytes induced by CTLA-4 crosslinking.

The CTLA-4 receptor is a critical inhibitory regulator of T cell proliferation and effector function. However, the mechanisms through which CTLA-4 modulates the activation of T cells remain uncertain. Initial studies, using activated human T cells, have suggested that CTLA-4 crosslinking may induce apoptosis.

Neonatal cranial ultrasonographic findings in preterm twins complicated by severe fetofetal transfusion syndrome.

Objective: To investigate cranial ultrasonographic findings in survivors of monochorionic pregnancies complicated by fetofetal transfusion syndrome.

Study Design: Case details of all monochorionic twin pregnancies complicated by fetofetal transfusion syndrome were obtained from the Centre for Fetal Care database for a 3-year period. Fetofetal transfusion syndrome was diagnosed according to ultrasonographic criteria.

Cerebral functional changes following cardiac surgery: Neuropsychological and EEG assessment.

Objective: Some form of organic and functional cerebral deficit may occur in up to one third of patients following cardiopulmonary bypass surgery. This study was designed to assess cerebral functional deficit in cardiac surgical patients.

Methods: Neuropsychological and quantitative electroencephalographic (EEG) changes were assessed in 62 first time coronary artery bypass graft surgery patients before surgery and within 1 week and 2 months after surgery.

The ureteric jet index: a novel measure of divided renal function.

The aim of this study was to evaluate an index of divided renal function based on the quantification of the ureteric jets seen on colour Doppler ultrasound of the bladder. Thirty-one patients attending for scintigraphic renography underwent colour Doppler ultrasound with video recording for 5 min. Divided renal function was calculated as the proportion of jets from the right-sided orifice ('jet index').

Adult onset of acute myeloid leukaemia (M6) in patients with Shwachman-Diamond syndrome.

Three male patients (two of whom were brothers) with Shwachman-Diamond (SDS) syndrome presented with acute myeloid leukaemia in adulthood. In all three cases there was trilineage myelodysplasia and the morphology was consistent with FAB subtype M6. SDS is an inherited bone marrow failure syndrome with a high propensity to leukaemic transformation.

Patient-controlled sedation for cataract surgery using peribulbar block.

Patients undergoing cataract surgery using peribulbar block were allocated randomly to self-administer doses of either midazolam 0.1 mg or propofol 3.3 mg without a lock-out facility; in the control group the syringe was charged with saline, not as a placebo, but to "blind" the surgeon and the nurse observer.

Detection and functional assessment of accessory splenic tissue (splenunculi) with radiolabelled heat damaged autologous erythrocytes.

Eight patients (six with idiopathic thrombocytopenic purpura, one with immune pancytopenia, and one with autoimmune haemolytic anaemia), who had previously been splenectomized, were found to have splenunculi using radioactively labelled heat damaged autologous erythrocytes. In all patients the splenunculi were found to have significant 'splenic function'. However, there was a poor correlation between the size and the function of the splenunculi.

Major surgery in von Willebrand's disease.

Two patients with von Willebrand's disease underwent major surgery, the first had aortic valve replacement and the second a total hip replacement. Clinically, the best practical test for monitoring the dose of cryoprecipitate necessary to maintain haemostasis was the bleeding time. The response to coagulation factor replacement in von Willebrand's disease is extremely variable, and it is necessary to maintain close coagulation monitoring until the patient's surgical condition is satisfactory for discharge from hospital.

The Value of Lactate and Pyruvate Measurements in the Assessment of the Redox State of Free Nicotinamide-Adenine Dinucleotide in the Cytoplasm of Perfused Rat Heart.

In the isolated rat heart perfused with glucose as substrate, measurements were made of perfusate and tissue lactate and pyruvate concentrations, and of tissue α-glycerophosphate and dihydroxyacetone phosphate concentrations. The conditions studied included increased heart work, anoxia, the addition of insulin, acute alloxan diabetes, chronic streptozotocin diabetes, and the addition of ketone bodies. True intracellular lactate values (estimated from the lactate and sorbitol spaces) and apparent tissue values exceeded perfusate values, showing the existence of a lactate concentration gradient.