Biomedical subjects
Publications and source records attributed to S Payne.
Nursing models tend to be based on theory, and are not always rigorously tested for effectiveness. For people with cancer, often the prime nursing input is aimed at improving quality of life. A model has been developed to better facilitate this, which may also apply in other specialties.
Racemic 1,5,6-tri-O-benzyl-myo-inositol was prepared by five routes and converted into 1,5,6-tri-O-benzyl-2,3-O-isopropylidene-myo-inositol, the camphanates of which were readily separated by chromatography. The absolute configurations of the chiral derivatives were established by their conversion into the known chiral 1,4,5,6-tetra-O-benzyl-myo-inositols. 1D-1,5,6-Tri-O-benzyl-2,3-O-isopropylidene-myo-inositol was converted into 1D-1,3,5,6-tetra-O-benzyl-myo-inositol and thence into 1D-2,4-di-O-methyl-myo-inositol. 1D-1,5,6-Tri-O-benzyl-myo-inositol was converted into 1D-1,2,5,6-tetra-O-benzyl-myo-inositol, the diacetate of which is a chiral analogue of "thermosalient crystals". The potential of the above compounds for the synthesis of natural products is surveyed.
The human genome contains many different types of endogenous proviruses and retrovirus-like elements. An unusual element of this kind has been isolated from human DNA on the basis of its relatedness to the integrase-coding domain of the pol gene of feline leukaemia virus (FeLV). The element, termed Hs5, is related to FeLV only over a short region of 81 nucleotides predicted to encode the carboxyl terminus of the FeLV integrase protein, p46pol. The region of relatedness between Hs5 and FeLV identifies a short conserved amino acid stretch which is shared among distantly related retroviruses. The conservation of this sequence, its position, and predicted secondary structure suggest that it may represent a conserved substrate binding site or active site of the integrase enzyme. Nucleotide sequence analysis of Hs5 reveals that it is not an intact retrovirus, but contains only the 3' terminus of pol and a defective env gene without apparent long terminal repeat; Hs5 is unusual among human endogenous retrovirus-like elements in this respect.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Doxorubicin (Adriamycin, ADR) is an anthracycline antineoplastic with the serious side effect of dose-related cardiomyopathy. A model of ADR cardiotoxicity was created to examine some subcellular toxic effects of ADR with cultured cardiac myocytes (CMCs) exposed to 1 x 10(-7) to 1 x 10(-5) M ADR for 24 to 48 hr. Lactate dehydrogenase (LDH) activity was monitored in the CMC medium to monitor CMC damage as a function of ADR concentration. A four- to eightfold elevation of LDH activity in medium of CMCs exposed to 1 x 10(-6) to 1 x 10(-5) M ADR was found. No change in LDH activity was detected in medium of CMCs exposed to 1 x 10(-7) M ADR or in control CMCs after 24 or 48 h ADR exposure. Data suggest a dose-dependent effect of ADR on LDH activity in CMC medium. Serial monitoring of LDH in media of ADR-exposed CMCs may correlate with other evidence of ADR cardiotoxicity in vitro.
Explore the source record for details and available documents.
A clinic to which general practitioners can refer patients for some types of orthopaedic appliances was opened in North Clwyd in 1983. During 1985, 956 patients were referred by 82 general practitioners; 860 patients received an appliance, and the average waiting time was less than five weeks. Most referrals were for soft collars (44%), lumbar sacral supports (30%), and dorsilumbar supports (7%). Thirty eight patients failed to attend, 54 declined an appliance, and four referrals were considered to be inappropriate. A few patients were subsequently referred to consultant outpatient clinics, 22 for physiotherapy and 34 were referred simultaneously to the open access clinic. The referral rates for general practitioners with access to community hospitals were low. Such an arrangement merits wider consideration.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Allyl 4-O-benzyl-alpha-L-rhamnopyranoside was converted into allyl 4-O-benzyl-3-O-methyl-alpha-L-rhamnopyranoside and this was condensed with 2,3,4-tri-O-acetyl-alpha-L-rhamnopyranosyl chloride to give a disaccharide derivative which was converted into allyl 4-O-benzyl-2-O-(2,3-O-isopropylidene-alpha-L-rhamnopyranosyl)-3-O-methyl -alpha- L-rhamnopyranoside. This disaccharide derivative was condensed with 2,4-di-O-acetyl-3,6-di-O-methyl-alpha-D-glucopyranosyl chloride to give a trisaccharide derivative which was converted into the title compound. This compound represents the oligosaccharide portion of the major serologically active glycolipid from Mycobacterium leprae which is required to prepare a synthetic diagnostic agent for leprosy infection at an early stage and to investigate the specificities of monoclonal antibodies directed towards the glycolipid.
The unique periodic nature of equine infectious anaemia (EIA) is believed to result from the ability of the infecting virus. EIAV, to undergo relatively rapid antigenic variations which circumvent host immune responses resulting in distinct virus populations in sequential clinical episodes in the persistently infected horse. This model was examined by oligonucleotide mapping comparisons of the RNA genomes of selected isolates of EIAV. Variations in oligonucleotide maps could be reproducibly demonstrated (i) after adaptation of the laboratory strain of EIAV to replication in a pony, (ii) after serial passage of virus between two ponies, and (iii) after a prolonged persistent infection in a single pony. In the latter case, the two isolates examined were recovered from different clinical episodes and were shown to be antigenic variants. In contrast, no variations in RNA structure could be detected in oligonucleotide maps of virus isolated after prolonged passage in tissue culture. Thus, these results support our concept that EIAV is a highly mutable virus, which may given rise to antigenic variants in the presence of immune pressures. The degree of variation observed between oligonucleotide maps is similar to that observed previously between variants of visna virus. These similarities between EIAV an visna suggest that genomic point mutations producing antigenic variants may be a more important mechanism of retrovirus persistence than was previously recognized.
Animal experiments have suggested that Puchel, a lipophilic derivative of DTPA may be of use in removing plutonium from humans after an accidental intake. This study reports toxicological findings in mice. After the administration of Puchel, as single or repeated doses of the pentasodium salt, an LD50/ld value of 530 +/- 44 mg kg-1 was obtained.
Explore the source record for details and available documents.
Ingestion of oral contrast material as a routine part of abdominal computerized tomographic scanning creates numerous gas and fluid interfaces within the gastrointestinal tract. Following deep inspiration or expiration, fluid motion induced by shifting intra-abdominal contents persists for several seconds. This causes radial streak artifacts to arise from air-fluid interfaces, even though respiration is suspended while the scan is made. Such artifacts can be reduced if the beginning of a scan is delayed to allow fluid motion to stop. An alternative is to re-scan an area of interest in the lateral decubitus position so as to shift air-fluid levels and their associated artifacts away from any region in question.
Explore the source record for details and available documents.
Preliminary studies have suggested that alpha-1-antitrypsin (A1AT) is a useful immunohistochemical marker of histiocytes (monocytes/macrophages) and malignant tumours derived from them. To confirm the reliability of this marker a wide variety of benign and malignant lymphoreticular cells and tissues have been stained by the immunoperoxidase technique for A1AT and positive staining was found to be confined to histiocytes. Immunodiffusion, isotope labelling, and isoelectric focusing studies performed on cell lysates confirmed that the positive staining shown by monocytes and malignant histiocytes is due to the presence of A1AT identical with serum A1AT and that this material is synthesised by these cells rather than taken up from their environment. Positive immunoperoxidase staining for A1AT is thus a reliable marker of lymphoreticular neoplasms of true histiocytic origin.
Explore the source record for details and available documents.