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S Edwards

Publications and source records attributed to S Edwards.

At least 181 records · Page 10Linked to original sources

Peripherally administered 5-hydroxytryptamine elicits the full behavioural sequence of satiety.

If 5-HT acts as a peripheral satiety signal, then it should not only produce anorectic effects when administered systemically but should allow the normal behavioural sequence of satiety to develop. Food-deprived rats treated with 5 mg/kg 5-HT were found to show, when given access to food, the full normal behavioural sequence of satiety, although the sequence occurred earlier than in rats treated with saline. It is therefore argued that 5-HT must be considered as a likely candidate for a peripheral satiety signal.

Animals↗

The development of an international reference panel of monoclonal antibodies for the differentiation of hog cholera virus from other pestiviruses.

A panel of 30 monoclonal antibodies was defined and characterized with respect to the binding capacity in immunoperoxidase assay to different strains of pestivirus. Using the panel it was possible to identify specifically all strains and isolates of hog cholera virus, hog cholera vaccines derived from 'C' strains, and most strains of bovine viral diarrhoea/border disease (BVD/BD) viruses (including those isolated from pigs). A small proportion of BVD/BD isolates from pigs and ruminants reacted only with the monoclonals specific for pestivirus group antigen. It is recommended that monoclonal typing methods be introduced into official procedures for the diagnosis of hog cholera/classical swine fever.

Animals↗

Chronic bullous disease of childhood with oral mucosal scarring.

Chronic bullous disease of childhood (CBDC) is an acquired subepidermal bullous disease; oral involvement occurs with mouth ulcers and blisters in 57% of patients. The condition usually remits before puberty but persistence of the disease in adulthood is recognized. We report a case with severe oral scarring similar to that described in patients with adult linear IgA disease. To our knowledge this has not been previously described.

Child↗

Demonstration of insulin transformation products in insulin vials by high-performance liquid chromatography.

OBJECTIVE: To assess the importance of temperature, light, agitation, and regular withdrawal of insulin on the rates of appearance of three groups of insulin transformation products (ITPs) in vials of human and beef soluble insulin. RESEARCH DESIGN AND METHODS: Twelve insulin-treated patients (6 receiving human soluble insulin, 6 receiving beef soluble insulin) participated in the study. Reverse-phase high-performance liquid chromatography was used to measure ITP in serial samples from vials stored in various laboratory environments or issued to patients. Vials in the laboratory were analyzed on nine occasions over 26 wk; those issued to patients were analyzed weekly. RESULTS: Results were expressed as rates of change (% total protein/wk). Except for human insulin stored at 4 degrees C, sampling did not accelerate transformation. Storage at higher temperatures caused more rapid transformation to all ITP groups, and human insulin was more susceptible than beef insulin. Exposure to light accelerated transformation mainly to group 3 ITP. Fibrillation occurred in beef but not human insulin carried in a shirt pocket. Results from patients' vials were consistent with reported storage conditions. CONCLUSIONS: All three ITP groups form in human and beef soluble insulin. Their rate of production is a function of temperature and light exposure. Differences between the two insulins were probably due to differences in formulation. Patients should be discouraged from hoarding vials and storing insulin in direct sunlight. One or more ITPs could contribute to the residual immunogenicity of modern insulin preparations.

Analysis of Variance↗

The effect of class II gene transfection on the tumourigenicity of the H-2K-negative mouse leukaemia cell line K36.16.

There is much evidence to suggest that potentially immunogenic tumour cells can escape cytolytic immune destruction by loss of class I antigen expression. Many tumours are allele-specific class I negative and, in murine systems, reconstitution of class I expression by gene transfection leads to an increase in tumour immunogenicity. In many systems where mice have rejected class I transfected tumour cells they are also immune to a subsequent challenge with the untransfected parent tumour. In this study we have examined the effect of stable class II antigen expression (induced by gene transfection) on a class I loss mutant (H-2Kk negative) murine cell line, K36.16. We show that H-2Ek expression is more effective at increasing tumour immunogenicity than the reconstitution of H-2Kk expression in these cells. This suggests that the induction of class II antigen expression on tumour cells may provide an effective way of enhancing tumour-specific immune responses in vivo.

Animals↗

Immunomagnetic purging of breast cancer from bone marrow for autologous transplantation.

Intensive chemotherapy with autologous bone marrow transplantation is a promising approach for the treatment of breast cancer, provided that clonogenic tumor cells do not contaminate the patient's bone marrow. We have previously demonstrated that a combination of 4-hydroperoxycyclophosphamide (4-HC) and immunomagnetic purging (IMP) with monoclonal antibodies and microspheres could remove 4-5 logs of clonogenic breast cancer cells from a 10-fold excess of human bone marrow cells. In the present report we have evaluated an apparatus for separating tumor cells from a large volume of human marrow. This apparatus will permit preparation of large volumes of purged marrow for use in studies of intensive therapy with autologous marrow support. Bone marrow progenitor cell (CFU-GM) recovery following this IMP technique was 85% of the unpurged control, and suggests that marrow recovery following high dose systemic chemotherapy will not be adversely affected. A phase I study to evaluate marrow reconstitution following IMP is underway. Preliminary data suggest that this IMP method will not delay engraftment in breast cancer patients receiving high-dose chemotherapy and autologous bone marrow support, but further study is required.

Adenocarcinoma↗

A study of the predominant genotypes of bovid herpesvirus 1 found in the U.K.

The genotypic classification of 84 U.K. isolates of bovid herpesvirus 1 was determined by the restriction endonuclease technique. Preliminary studies with six enzymes (EcoRI, HindIII, HpaI, BamHI, PstI and BstEII) showed that the principal genotypic variants, including the live vaccine strains used in the U.K., could be identified from the digestion patterns with just two endonucleases: HindIII and HpaI. Isolates from the 1960s were all categorised as genotype 2b. From 1977 onwards, genotype 1 has predominated in mainland Britain, with occasional type 2b isolates. Type 2b viruses were isolated from both respiratory and genital disease cases. There was no evidence of genotypes 2a or 3 in the U.K.

Animals↗

Round table on infectious bovine rhinotracheitis/infectious pustular vulvovaginitis virus infection diagnosis and control.

The current situation of infectious bovine rhinotracheitis/infectious pustular vulvovaginitis infection in various European countries is reviewed. Whilst some have a high serological prevalence and use live virus vaccines to control the disease, others have a low prevalence and two countries (Denmark and Switzerland) have national eradication schemes which are almost complete. Serology remains important for diagnosis although other tests such as delayed cutaneous hypersensitivity may have a role to play. New tests such as polymerase chain reaction may find increasing application where high sensitivity is required, such as the detection of virus in semen.

Animals↗

Age-related differences in cardiovascular reactions to mental stress tests in women.

Tested 84 healthy, sedentary women in the laboratory during performance of difficult and easy problem-solving tasks. They were divided into three age groups: 19 to 32 years, 33 to 43 years, and 44 to 60 years (n = 28 women per group). Baseline systolic blood pressure (SBP) and diastolic blood pressure increased with age, whereas skin conductance level was lower in older women. In addition, initial SBP reactions to tasks were positively related to age, even after controlling for baseline blood pressure, aerobic fitness, and Framingham Type A Scale behavior scores. There were no differences in heart rate (HR) or "additional" HR reactions, so the anticipated decline in cardiac sympathetic response with age was not observed. The mechanisms underlying age-related reactions to mental stress are discussed.

Adult↗

The relationship of DNA double-strand break induction to radiosensitivity in human tumour cell lines.

Recent data suggest that the differences in radiosensitivity between cell lines can be related to differences in dsb induction (Radford 1986a). In the light of this we have set out to assess the extent to which differences in radiation survival between human tumour cell lines can be attributed to differences in dsb induction. For nine human tumour lines survival was assayed by clonogenic assay and compared with dsb induction by irradiation at ice-bath temperature as measured by neutral filter elution. The lines varied widely in their sensitivity, ranging from a sensitive neuroblastoma (surviving fraction at 2 Gy, SF2 = 0.13) to a resistant bladder carcinoma (SF2 = 0.62). Dsb induction was found to vary between the cell lines, such that resistant cells generally suffered less damage than sensitive ones. However, the relationship between damage induction and cellular sensitivity was not a simple one, and other factors which may influence sensitivity need to be invoked. These data suggest that, in human tumour cell lines, differences in radiosensitivity may at least in part be due to different levels of damage induction, but that some lines may vary in their tolerance of damage due to differences in biological characteristics such as repair capacity.

Cell Line↗

Angina bullosa haemorrhagica--a report of three cases and review of the literature.

Angina bullosa haemorrhagica (ABH) is a term that was first introduced by Badham in 1967 to describe a bullous disorder in which recurrent oral blood blisters appear in the absence of any identifiable systemic disorder. The aetiology of this condition remains obscure. Three cases are described, and their similarities and differences discussed. In one case the histopathology showed an intradermal blister; this feature has not previously been recorded for this condition.

Adult↗

Aerobic fitness, physical activity, and psychophysiological reactions to mental tasks.

The association between aerobic fitness, exercise, and psychophysiological reactivity was assessed in cross-sectional and prospective analyses. Seventy-five healthy but sedentary adults carried out a sub-maximal exercise test and easy and difficult problem solving tasks. Blood pressure, heart rate, skin conductance level, respiration rate, tidal volume, and oxygen consumption were monitored and additional heart rate was also computed. Differences between relatively fit and unfit individuals were found in respiration rate during tasks and in skin conductance level during post-task recovery periods, with a tendency toward diminished heart rate reactivity in fitter people. Subjects were subsequently allocated to four conditions: high intensity aerobic training, moderate intensity aerobic training, an undemanding strength and flexibility program (designed as an attention-placebo condition), and waiting list control. Training programs were conducted over a 10-week period, and were followed by a second laboratory session. Appropriate changes in aerobic performance over the training period were observed in the 12-min run/walk test. There were no important modifications in psychophysiological stress reactions associated with the different experimental conditions. These results are discussed in relation to the literature concerning the effects of fitness and physical activity on physiological response patterns.

Adult↗

The diagnosis of bovine virus diarrhoea-mucosal disease in cattle.

Laboratory diagnostic procedures for bovine virus diarrhoea and mucosal disease are reviewed. For serology, emphasis is placed on the virus neutralisation test and enzyme immunoassays. The techniques and the pitfalls which may be encountered in culture procedures for isolation of the virus are described, with special reference to the use of immunofluorescence and immunoperoxidase methods for the detection of non-cytopathogenic virus strains. Viral antigen may also be detected directly in clinical or pathological samples. Monoclonal antibodies are expected to play an increasing role in diagnostic tests, and the application of gene probes for virus detection is anticipated in future years. In the interpretation of diagnostic laboratory test results, the importance is stressed of reviewing them in the context of the herd disease and breeding history, and relating them to current understanding of the pathogenesis and epidemiology of the disease.

Animals↗

A blocking ELISA to differentiate hog cholera virus antibodies in pig sera from those due to other pestiviruses.

The blocking ELISA technique was extended to comparative serology by using 3 different pestivirus strains: Hog cholera virus (HCV) Alfort strain propagated in PK15 cell line, Border disease virus (BDV) Aveyron strain in PK15 and BVD NADL** strain in fetal calf kidney (FCK) primary cells. Rabbit antisera to the Alfort HCV strain and Aveyron BDV strain were raised for use in the test. A bovine hyperimmune serum to BVD virus was also used for detecting antibodies specific to BVD virus. The ELISA was compared with the neutralisation test on various groups of field and experimetnal porcine sera. The results obtained with the ELISA were well correlated with the neutralisation test. Therefore the ELISA may be recommended as a differential serological test between HCV and other pestivirus antibodies in pig sera.

Animals↗