Development of a solute and defect concentration dependant Ising model for the study of transmutation induced segregation in neutron irradiated W-(Re, Os) systems.

In this study, radiation-induced precipitation of transmutation products is addressed via the development of a new solute and vacancy concentration dependant Ising model for the W-Re-Os system. This new model includes interactions between both Os and Re atoms with vacancies, thus facilitating more representative simulations of transmutation in fusion reactor components. Local solute concentration dependencies are introduced for the W-Re, W-Os and Re-Os pair interactions. The model correctly accounts for the repulsion between small clusters of vacancies and the attraction between larger clusters/voids, via the introduction of local vacancy concentration dependant interaction coefficients between pairs of atoms and vacancies. To parameterise the pair interactions between atoms and/or vacancies, the enthalpy of mixing, ΔHmix, for various configurations and solute/defect concentrations, was calculated using density functional theory, within 6 binary systems: W-Re, W-Os, Re-Os, W-vacancy, Re-vacancy and Os-vacancy. The new energy model was implemented into the SPPARKS Monte Carlo code, and successfully used to predict the formation of voids decorated with Re and Os solute atoms. Analysis suggests that there is a strong thermodynamic tendency for Os to bind to these voids with a comparatively weaker binding from Re atoms. The binding energies of various solute/vacancy clusters were calculated and showed that Re and Os solute atoms tend to stabilise small clusters of vacancies, increasing the attractive binding energy between the constituents.

Severe coagulation defect due to a dietary deficiency of vitamin K.

A patient with multiple injuries developed a severe coagulation defect due to a deficiency of vitamin K. None of the usual predisposing factors was present and the patient's diet was very poor. Dietary deficiency of vitamin K and the importance of antibiotic therapy in its production are discussed.

Mechanized blood grouping: a hospital trial using an 8-channel grouping machine.

ABO and Rh (D) groups of 6403 blood samples were assessed on an 8/9-channel autoanalyser in the Serology Department of the London Hospital; the results were independently checked at the Regional Blood Transfusion Centre, Brentwood, using the routine methods for grouping donor blood. Results of this comparative study are given and instances are described in which anomalous results or incorrect groupings occurred; the possible causes are discussed. The 8/9-channel automated blood group analyser is evaluated in terms of routine hospital laboratory practice.

Assessment of children's colour vision using the Pickford-Nicolson anomaloscope.

The colour vision of 439 boys, aged 4-11 years, was measured by the Pickford-Nicolson anomaloscope and four pseudoisochromatic tests. Matching range and dispersion of mid match point were found to be larger than adult values, but did not decrease with age. However, younger children took longer to establish matching range. Twenty-eight (6.4%) colour defectives were found and it is concluded that the Pickford-Nicolson anomaloscope gives valid results with children.

Angioedema responding to antiprotease treatment but without abnormalities of the complement system.

Four patients suffered from chronic or recurrent angioedema, of sudden onset in adult life, associated with visceral pain and impossible to control by dietary means. In spite of normal complement function they respond very well to tranexamic acid therapy. Antiprotease drugs need not be restricted to cases of ClsINH deficiency.

Intravenous lignocaine in prevention of deep venous thrombosis after elective hip surgery.

Intravenous lignocaine is a possible means of preventing deep venous thrombosis (D.V.T.) after elective hip surgery. In 14 control patients the total incidence of D.V.T. was 78%, with a 57% incidence of thigh-vein thrombosis. In 14 patients treated at random with intravenous lignocaine during the first 6 postoperative days, there were only 2 calf-vein thrombi (14%; P less than 0-005). In a further 14 cases treated consecutively there were 4 unilateral calf-vein thrombi. No thrombi originated in the thigh veins (P less than 0-001). After intravenous lignocaine was stopped the total incidence of D.V.T. in the 28 patients rose to 53% with a 21% incidence of thigh-vein thrombi between the 7th and 14th postoperative days. There was no significant difference in postoperative coagulation and fibrinolytic activity between control and treated patients, and blood loss and transfusion requirements were similar. Immediate or delayed hypersensitivity reactions to lignocaine were not observed. The results support the view that damage to the vessel wall may be the initial event in the formation of a venous thrombus.

Phase II trial of thymosin fraction 5 in advanced renal cancer.

Partially purified thymosin fraction 5 ( TF5 ) was administered to 21 patients with advanced renal cancer. Two different loading dose schedules and doses (60 and 120 mg/m2) of SQ TF5 were employed in 10 patients each. Of 20 evaluable patients, three exhibited partial responses and two exhibited stable disease. All five of these patients had had prior nephrectomies and lung metastases as the dominant site of disease. Toxicity was minimal but included one probable systemic allergic reaction. We could not identify any specific relationship between TF5 dose/schedule or pretreatment immune abnormalities and tumor responsiveness. Our results indicate that the administration of TF5 alone can induce regressions of renal cancer. Additional trials with larger numbers of patients appear to be justified.

Recombinant leukocyte A interferon in B-cell chronic lymphocytic leukemia: in vivo effects on autologous antitumor immunity.

Eight previously treated and four untreated patients with B cell chronic lymphocytic leukemia (CLL) received 20 X 10(6) U/m2 recombinant leukocyte interferon clone A (rIFN-alpha A) intramuscularly three times a week for 8 weeks. None of the eight patients who had received prior chemotherapy exhibited objective evidence of tumor regression. Two of the four previously untreated patients responded with transient (90%) decreases in absolute lymphocyte counts lasting for 2 and 7 months. Toxicity was moderate, with all patients experiencing a flu-like syndrome requiring a 50% dose reduction. Half of the patients exhibited anorexia, weight loss, and a drop in performance status. The two responders had normal serum immunoglobulin levels prior to treatment, whereas 80% of non-responders had depressed levels. Treatment with rIFN-alpha A was associated with a depression of nonspecific and specific humoral immunity in assays employing cryopreserved autologous pretherapy CLL cells. No consistent effects were demonstrable in cytolytic assays with purified peripheral blood T cells as effector cells, including one that utilized autologous CLL target cells. rIFN-alpha A has limited antitumor activity in B cell CLL which is restricted to untreated patients with an early stage of disease. With the assays employed it was not possible to demonstrate that rIFN-alpha A could augment autologous antitumor immunity.

A randomized trial to evaluate the immunorestorative properties of synthetic thymosin-alpha 1 in patients with lung cancer.

A randomized trial was performed in 42 postradiotherapy patients with non-small cell lung cancer to determine whether the administration of synthetic thymosin-alpha 1 by either a loading dose or a twice-weekly schedule could accelerate the reconstitution of thymic dependent immunity. The radiotherapy-induced immunosuppression was characterized by an absolute T cell lymphopenia and by impaired T cell function in lymphoproliferative assays. Placebo-treated patients did not show any improvement in T cell numbers or function over 15 weeks of serial immune monitoring, and exhibited gradual depressions of helper T lymphocyte percentages. Patients treated with thymosin by the loading dose regimen exhibited a normalization of T cell function (p = 0.04), whereas patients treated with the twice-weekly schedule maintained normal helper T cell percentages (p = 0.04). Thymosin treatment was associated with significant improvements in relapse-free and overall survival, which was most pronounced for patients with nonbulky tumors. Thymosin-alpha 1 exhibits schedule-dependent immune restorative and homeostatic properties. Large scale Phase III trials are indicated to definitively establish the impact of thymosin therapy in lung cancer patients treated with radiotherapy.