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K Britton

Publications and source records attributed to K Britton.

18 recordsLinked to original sources
PubMed1992

User requirements for information systems in nuclear medicine.

In the field of COST cooperation (COST = European Cooperation in the Field of Scientific and Technical Research) a project B2 for Quality Assurance in Nuclear Medicine Software has been established. In a memorandum of understanding setting up this project, user requirements were to be defined for the hardware and software used for data acquisition, processing and presentation. A subgroup of the management committee of COST B2 were interested in the Advanced Informatics in Medicine, AIM, task T-734 'Quality Assurance of Medical Software', and the AIM Project 'A 1034', coordinated by Dr K. Britton, was initiated. The initial drafts of this document were written in Helsinki during 1988-1990, and submitted for comment by the members of the management committee of COST B2. These comments were integrated in the text and this document was finalized by the UK group so as to make it available for international discussion. It is anticipated that, after appropriate international discussion, these User Requirements for Information Systems in Nuclear Medicine will be adopted by the management committee of COST B2 as a COST document. Towards these ends, a working group chaired by Dr Britton, including the British and Finnish teams and Ulrich Noelpp from Switzerland, was appointed by the management committee of COST B2 in April 1990. While writing it we have had the pleasure of working with referees from different European hospitals in many countries. We are happy to thank all of them for their valuable contributions.

Europe↗
PubMed1989

Central corticotropin releasing factor reduces natural cytotoxicity. Time course of action.

Corticotropin-releasing factor (CRF) administered intracerebroventricularly produced both a rapid, greater than 50% reduction in splenic natural killer (NK) cytotoxicity and a prolonged elevation in plasma corticosterone levels. In the first 60 minutes following CRF, fivefold increases in corticosterone levels were associated with the suppression of NK activity. However, NK activity returned to control levels at later time points even though elevated plasma corticosterone levels persisted. These data augment the findings that central CRF reduces natural cytotoxicity and establish a time course for the effect in acutely treated rats.

Animals↗
PubMed1988

The treatment of intraperitoneal malignant disease with monoclonal antibody guided 131I radiotherapy.

Seven patients with small volume ovarian carcinoma, remaining after conventional therapy with surgery and a platinum containing chemotherapy regimen, were treated with intraperitoneal monoclonal antibody guided radiotherapy. 100 mCi131I conjugated to 10 mg of monoclonal antibody were injected i.p. in 2,000 ml peritoneal dialysis fluid. Patients were evaluated 3 months later; 3 had clinical progressive disease while third look laparotomy demonstrated progressive disease in 3 of the remaining 4 patients. The seventh patient did not have a third look laparotomy and is currently inevaluable for response. Five patients with recurrent malignant ascites not controlled by diuretics or repeated paracentesis were similarly treated with 75-170 mCi131I conjugated to 10 mg monoclonal antibody. In three patients the ascites was controlled for a mean of 4 months. One patient died too early to assess the control of his ascites but tumour cells disappeared from the ascitic fluid after therapy. In the patient whose ascites were not controlled, a subpopulation of antigen-negative tumour cells was demonstrated. This study was unable to demonstrate a therapeutic benefit for i.p. injected monoclonal antibody guided radiotherapy for solid intraperitoneal tumour but suggests that it may be capable of controlling the accumulation of antigen positive malignant ascites.

Adult↗
PubMed1984

Oral administration of cyclosporin A for recipients of allogeneic marrow transplants: implications of clinical gut dysfunction.

Cyclosporin A (CyA) was used to minimize graft-versus-host disease (GVHD) in 28 recipients of allogeneic marrow transplants. When given orally, the absorption of CyA was markedly dependent on normal gut function. Patients without gut dysfunction showed normal serum concentration-time curves while those with diarrhoea from any cause (chemo-radiation enteritis, acute GVHD of the gut, infectious enteritis) showed minimal absorption of the drug. These data indicate the desirability of the intravenous administration of CyA during periods of gut dysfunction in marrow transplant recipients.

Administration, Oral↗
PubMed1984

Distribution and concentration of cyclosporin in human blood.

In patients receiving cyclosporin to minimise graft versus host disease after allogeneic bone marrow transplantation, whole blood cyclosporin concentration was roughly twice the serum concentration when blood was separated at 37 degrees C. In turn, blood separation at 37 degrees C resulted in a doubling of serum cyclosporin concentration compared with separation at room temperature. In vitro studies showed that the latter phenomenon was due to a temperature dependent partitioning of cyclosporin between plasma and red cells, such that increased cyclosporin was taken up from the serum into red cells at room temperature. Increasing delay in separation of patient blood (at either temperature) resulted in a gradually increasing cyclosporin serum concentration. Further in vitro studies showed that a distribution equilibrium between blood components was reached within 30 min incubation. Red cell uptake of cyclosporin was saturable at an incubation concentration of greater than 4 microgram/ml, while plasma and mononuclear cells showed a linear uptake to 7 micrograms/ml. The cellular cyclosporin content of a mononuclear cell was roughly 1000 times greater than that of an erythrocyte. For clinical monitoring we recommend the measurement of cyclosporin concentration either in whole blood or in serum separated at 37 degrees C without delay after venepuncture.

Bone Marrow Transplantation↗
PubMed1984

Tissue distribution and toxicity of cyclosporin A in the mouse.

Groups of mice were given cyclosporin A (CyA) subcutaneously for 6 wk at a dose of 12.5, 50 or 200 mg/kg/d. After 7, 21 and 42 days of CyA administration the CyA content of serum, thymus, mesenteric lymph nodes, spleen, kidney, liver, lung, small and large intestine and brain was measured, each organ was examined histologically, and the total viable nucleated cell content of thymus, mesenteric lymph nodes, spleen and femoral marrow was analysed. CyA was detected in every organ assayed at each concentration of CyA administered. The mean concentration of CyA per organ was consistently highest in organs of mice given CyA 200 mg/kg/d and lowest in those given 12.5 mg/kg/d at each time point, but there was pronounced variability in the concentration of CyA between individual mice. Repeated administration of CyA after the first week did not further elevate CyA tissue concentrations. At doses of 50 or 200 mg/kg/d CyA caused weight loss, diarrhea, intussusception and fatal neurotoxicity. In addition, the spleen, thymus and mesenteric lymph nodes of mice given CyA 50 or 200 mg/kg/d were hypocellular and disorganized, and all lymphoid organs contained numerous pyknotic lymphocytes. The liver showed fatty change and the kidney degeneration of proximal tubules. Femoral marrow showed enlarged and congested sinuses. No abnormalities were noted in mice given CyA 12.5 mg/kg/d.

Animals↗
PubMed1984

Monoclonal antibodies for successful tumour imaging.

The monoclonal antibody HMFG-2 which is directed to an oligosaccharide determinant on a large molecular weight mucin-like molecule found in the human milk fat globule reacts positively with breast and ovarian carcinomas. The purified antibody, labelled with 123I has been used successfully to locate ovarian tumours and their metastases in 20 out of 22 patients tested. Here we discuss those features of a) the antibody, b) the antigenic site it reacts with, c) the radioactive label and d) the scanning technique, which have contributed to the successful application of HMFG-2 to the effective imaging of ovarian tumours.

Antibodies, Monoclonal↗
PubMed1981

A multiobserver comparison of 99mTcO4 and 123I thyroid imaging.

The thyroids of forty patients were imaged using 2 mCi(74 MBq) 99mTc pertechnetate (99mTcO4) followed within one week by 2 mCi (74 MBq) 123I Iodide. The images obtained were evaluated by eight observers for 6 morphological criteria and assigned to 6 diagnostic categories with a confidence grading on a seven level scale (grade 1 being that for maximum confidence). Images were obtained with 123I for the same counts and the same times as those with 99mTcO4 and compared using an index in which the number of diagnostic categories and the mean confidence grading within each category were taken into account. The mean index obtained for 99mTcO4 images (9.2) was significantly greater (P less than 0.05, thus representing a lower observer confidence and less interobserver diagnostic agreement) than the mean indices for 123I equal count images (5.6) and 123I equal time images (6.8). The diagnoses made on the basis of 123I images were more frequently concordant with the final diagnosis after six months follow up (75% for equal counts and 77% for equal time) than those with 99mTcO4(63%). The radioisotope of iodine most suited to modern nuclear medicine instrumentation and with the most favourable radiation dosimetry is 123I which is recommended for those areas of thyroid imaging where iodine is superior.

Humans↗