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Biomedical subjects

R W Shaw

Publications and source records attributed to R W Shaw.

At least 181 records · Page 10Linked to original sources
PubMed1986

Reversible pituitary ovarian suppression induced by an LHRH agonist in the treatment of endometriosis--comparison of two dose regimens.

Buserelin [D-Ser(TBU)6-des Gly NH2(10) LHRH ethylamide], an LHRH agonist, was administered intranasally at two dose levels, 200 micrograms t.d.s or 300 micrograms t.d.s., to 20 women with proven endometriosis, many with recurrent disease. Both dose schedules achieved significant suppression of circulating 17 beta-oestradiol levels often to within the postmenopausal range, the larger dose inducing significantly greater suppression (P less than 0.05). Serum FSH values were suppressed below baseline but serum LH remained at pretreatment levels or above, whilst on treatment. Complete resolution of endometriotic deposits was achieved in 68% of cases following 6 months treatment with dramatic and long-standing relief of symptoms with no apparent dose difference. In all other subjects there was significant reduction in the extent of endometriotic deposits and improvement in American Fertility Society classification of disease stage. The most commonly occurring side effect was hot flushes; their intensity and frequency related to the degree of suppression of serum oestradiol and the dose of Buserelin administered.

Buserelin↗
PubMed1985

Identification of the components of a putative cytochrome bc1 complex in Rhodopseudomonas viridis.

Chromatophore membranes isolated from the bacteriochlorophyll b-containing, photosynthetic purple nonsulfur bacterium, Rhodopseudomonas viridis, have been shown to contain a Rieske iron-sulfur protein, a cytochrome similar to cytochrome c1, and also at least one b-type cytochrome. These observations suggest the presence of a previously undetected cytochrome bc1 complex in this bacterium.

Bacterial Chromatophores↗
PubMed1985

Effect of an intranasal LHRH agonist on gonadotrophins and hot flushes in post-menopausal women.

Alterations in circulating gonadotrophins have been reported at the time of onset of menopausal flushes. In order to study this association D-SER(TBU)6-EA10-LHRH, a luteinizing hormone releasing hormone (LHRH) agonist was given intranasally at a dose of 200 micrograms twice daily to 12 post-menopausal women to study its effect on gonadotrophin secretion and hot flushes. Following an initial period of 3-5 days of increased gonadotrophin secretion, pituitary desensitization occurred, with a significant suppression of circulating LH and follicle-stimulating hormone (FSH) levels (P less than 0.001) and a reduction in gonadotrophin pulse amplitude (P less than 0.05). This was accompanied by a significant diminution of the pituitary's response to exogenous LHRH (P less than 0.05). However, no significant alteration in the incidence of hot flushes was observed on such therapy.

Administration, Intranasal↗
PubMed1984

Dual-mode EPR spectrometry of O2-pulsed cytochrome c oxidase.

O2-activated bovine heart cytochrome c oxidase has been examined by dual-mode EPR spectrometry. Resonances have been observed at g = 10 and 4.5 in the parallel mode and at g = 10, 5, 1.8 and 1.7 in the normal mode. The bulk of these signals are interpreted to come from a stoichiometric S = 2 system with magnitude of a = 0.17 cm-1, D = +2.1 cm-1, magnitude of E = 0.026 cm-1, g = 2. Exchange coupling between cytochrome a3 and CuB is not indicated.

Animals↗
PubMed1984

The effects of bromocriptine on the sexual behaviour of hyperprolactinaemic man: a controlled case study.

A 44-year old man presented with loss of sexual interest and erectile failure and together with his wife was treated successfully with sexual counselling. He was subsequently found to have been hyperprolactinaemic before and after sex therapy. Comparison of bromocriptine with placebo in two double blind studies showed a modest increase in sexual interest when his prolactin levels fell to normal. In this case, the principal effect of hyperprolactinaemia was on sexual interest. His main problems, erectile impotence and decline in sexual activity, resulted from his and his wife's psychological reaction to this modest hormonal effect. Hyperprolactinaemia appears to have a similar effect to testosterone deficiency in men.

Adult↗
PubMed1984

Effects of chronic luteinizing hormone-releasing hormone agonist treatment on dysfunctional uterine bleeding in the stumptailed macaque.

Dysfunctional uterine bleeding is a disorder which presents problems for effective treatment and management. We have utilized the ability of chronic LRH agonist treatment to suppress ovarian steroid production to examine its effects on stumptailed macaques with a detailed history of excessive days of menstrual bleeding. Five monkeys were treated for 6 months with daily injections of D-Ser[But]6 LRH (1-9) nonapeptide-ethylamide. This was successful in suppressing ovarian steroid production in all monkeys as indicated by the maintenance of serum concentrations of oestradiol at less than 100 pg/ml and progesterone at less than 1 ng/ml. All monkeys menstruated for their typical time period during the first treatment cycle, but thereafter bleeding stopped in 2 monkeys and was considerably reduced in a further 2. In the remaining monkey, no significant improvement occurred. The results indicate that suppression of ovarian function in this way may have a significant role to play in the treatment of dysfunctional uterine bleeding.

Animals↗
PubMed1983

Intranasal treatment with luteinising hormone releasing hormone agonist in women with endometriosis.

An agonist analogue of luteinising hormone releasing hormone (buserelin) was successfully used to treat women with endometriosis. A dose of 200 micrograms administered intranasally thrice daily was found to be effective in five patients, in whom the endometriotic lesions resolved after six months' treatment. Failure occurred in a sixth patient, who received only 400 micrograms once daily. Anovulation was induced in all subjects together with suppression of menstruation after the first month of treatment. Symptoms of abdominal pain, dysmenorrhoea, and dyspareunia were relieved during treatment, and one previously infertile patient conceived within two months of stopping treatment. No side effects were reported with this dosage, and the results suggest a new form of treatment for patients with endometriosis.

Adult↗
PubMed1983

Multiple frequency EPR studies on three forms of oxidized cytochrome c oxidase.

Bovine heart mitochondrial cytochrome c oxidase (cytochrome aa3) (EC 1.9.3.1) has been demonstrated to occur in several forms when the redox centers in the protein are thought to be fully oxidized. We report here the results of extensive EPR studies at 3, 8.9, 9.2, 9.4, 15 and 34 GHz on the resting state, the alternative resting state (with g = 12 at 9 GHz) and pulsed state (with g = 5 signal at 9 GHz). Theoretical consideration is given to all binary spin-coupling possibilities under the constraint that the iron atoms are either ferric or ferrous and the copper atoms are either cupric or cuprous. We conclude that the g = 12 signal can arise from any spin system with S greater than 1 and D = 0.15 cm-1. The g = 5 signals originate from an excited, integer-spin system with D = 0.035 cm-1, which is approximately 7 cm-1 above the ground state (not observed in EPR). It is pointed out that in interpretations of data and elaboration of suitable models in this field, the implications of spin-coupling should be considered in a comprehensive and not in a selective way. At 3 GHz, EPR spectra of CuA in the resting, pulsed and anaerobically oxidized states show that this center is identical in its EPR for all three states.

Animals↗
PubMed1983

Specific binding of luteinizing hormone releasing hormone to human luteal tissue.

Homogenates of human luteal tissue bound radioiodinated luteinizing hormone releasing hormone agonist. Specific binding was both time- and temperature-dependent. Native LHRH and two LHRH agonists competed for binding, whereas TRH, somatostatin and oxytocin did not, indicating that the binding sites were specific. The apparent Ka values were 2 X 10(7)M-1 for both LHRH agonists and 10(6)M-1 for native LHRH. This is the first demonstration of specific binding of LHRH to human ovarian tissue. No binding could be detected to ovarian tissue from postmenopausal women.

Binding, Competitive↗
PubMed1983

Solvent proton relaxation studies of cytochrome c oxidase solutions.

The interaction of solvent water protons with the bound paramagnetic metal ions of beef heart cytochrome c oxidase has been examined. The observed proton relaxation rates of enzyme solutions had a negative temperature dependence, indicating a rapid exchange between solvent protons in the coordination sphere of the metal ions and bulk solvent. An analysis of the dependence of the proton relaxation rate on the observation frequency indicated that the correlation time, which modulates the interaction between solvent protons and the unpaired electrons on the metal ions, is due to the electron spin relaxation time of the heme irons of cytochrome c oxidase. This means that at least one of the hemes is exposed to solvent. The proton relaxation rate of the oxidized enzyme was found to be sensitive to changes in ionic strength and to changes in the spin states of the metal ions. Heme a3 was found to be relatively inaccessible to bulk solvent. Partial reduction of the enzyme caused a slight increase in the relaxation rate, which may be due to a change in the antiferromagnetic coupling between two of the bound paramagnetic centers. Further reduction resulted in a decreased relaxation rate, and the fully reduced enzyme was no longer sensitive to changes in ionic strength. The binding of cytochrome c to cytochrome c oxidase had little effect on the proton relaxation rates of oxidized cytochrome oxidase indicating that cytochrome c binding has little effect on solvent accessibility to the metal ion sites.

Animals↗
PubMed1983

Mullerian mixed tumour of the uterine corpus: a clinical histopathological review of 28 patients.

Clinical and histopathological features of 28 patients with Mullerian mixed tumours of the uterine corpus presenting to the Birmingham and Midland Hospital for Women between 1972 and 1977 are reviewed. The 5-year survival value for this group of patients was 25% with 53.5% of patients dying within 12 months of diagnosis. The most important finding of prognostic value was the extent of the tumour at the time of diagnosis and where this was localized to the uterus, there was a 50% 5-year survival. The presence of specific types of heterotopic elements or numbers of mitotic elements were not correlated with outcome. Five patients had previously received radium for induction of a radiation menopause and the relevance of this treatment and other factors in the aetiology of the tumour are discussed.

Aged↗
PubMed1983

Medical ethics: a survey of general practitioners' attitudes.

A postal questionnaire was used to investigate general practitioners' attitudes to several issues of medical ethics: artificial insemination, contraception, termination of pregnancy, euthanasia and criteria for brain death. The 500 doctors surveyed were all practising in the west of Scotland; 301 forms were returned (60 per cent response).

Adult↗