Showing papers by "University of Manchester published in 1988"

Detecting anxiety and depression in general medical settings.

Abstract: To aid general practitioners and other non-psychiatrists in the better recognition of mental illness short scales measuring anxiety and depression were derived by latent trait analysis from a standardised psychiatric research interview. Designed to be used by non-psychiatrists, they provide dimensional measures of the severity of each disorder. The full set of nine questions need to be administered only if there are positive answers to the first four. When assessed against the full set of 60 questions contained in the psychiatric assessment schedule they had a specificity of 91% and a sensitivity of 86%. The scales would be used by non-psychiatrists in clinical investigations and possibly also by medical students to familiarise them with the common forms of psychiatric illness, which are often unrecognised in general medical settings.

Acetylcholine releases endothelium-derived hyperpolarizing factor and EDRF from rat blood vessels.

Abstract: 1. The effects of haemoglobin and methylene blue on the acetylcholine (ACh)-induced electrical and mechanical responses of smooth muscle cells were investigated in rat aorta and rat main pulmonary artery. 2. When the endothelium was intact, ACh induced a transient hyperpolarization and sustained relaxation of tissues precontracted with noradrenaline. Both hyperpolarization and relaxation were absent in preparations without endothelium. 3. Haemoglobin and methylene blue inhibited the ACh-induced relaxation, but not the transient hyperpolarization. 4. In aorta with an intact endothelium, ACh produced an increase in both the rate of 86Rb efflux and tissue cyclic GMP levels. The changes in ion flux were unaffected by either haemoglobin or methylene blue in concentrations which almost abolished the increase in cyclic GMP concentrations. 5. In arteries with an intact endothelium, indomethacin had no effect on the ACh-induced electrical and mechanical responses or on the increase in 86Rb efflux and tissue cyclic GMP levels. 6. It is concluded that in the rat aorta and rat main pulmonary artery, ACh releases two different substances, an endothelium-derived relaxing factor (EDRF) and a hyperpolarizing factor (EDHF), from the endothelial cells. Neither substance appears to be derived from a pathway dependent on cyclo-oxygenase. EDHF seems to play a minor role in the relaxation of noradrenaline-induced contractions.

Proteoglycan-fibrillar collagen interactions

Abstract: The future of biochemistry lies in understanding how single gene products associate and function together. Interactions in connective tissues, including those between the proteoglycans and collagens are especially piquant, evolutionarily conserved and physiologically significant. Connective tissues (e.g. skin, tendon, blood vessels, etc.) are systems of insoluble fibrils and soluble polymers which evolved to take the stresses of movement and the maintenance of shape [1]. The fibrils resist pulling forces, and the interfibrillar soluble polymers resist compressive forces, like the stuffing in a cushion. Cells communicate biochemically through the soluble polymer compartment. Within this simple framework, multicelled organisms developed [1]. It was often speculated that there were specific associations between fibrils and soluble polymers. These ideas were extremely general, lacking chemical knowledge of the participants, and methods for diagnosing interactions. The situation now tends to the other extreme. Sensitive methods discover many 'specific' liaisons in vitro. Even when these are observed at physiological pH, temperature and ionic strength, caution is needed. The very large polymers characteristic of connective tissues (collagens, proteoglycans etc.) have

Does leadership make a difference to organizational performance

Abstract: ? 1988 by Cornell University 0001 -8392/88/3303-0388/$1 00 This paper evaluates research on the impact of chief executive officers on corporate performance, taking Lieberson and O'Connor's pathbreaking study as its starting point Although that study is commonly regarded as the principal source of empirical support for the view that leaders have little impact on organizational performance because they are constrained by situational factors, it is argued here that the study and its derivatives have provided consistent and compelling evidence that individual leaders do make a difference The results of a study of large retail firms in the United Kingdom, designed to overcome the methodological problems of earlier studies of leadership and performance, are presented in support of this argument

Model theory and modules

Abstract: The model-theoretic investigation of modules has led to ideas, techniques and results which are of algebraic interest, irrespective of their model-theoretic significance It is these aspects that I will discuss in this chapter, although I will make some comments on the model theory of modules per se Our default is that the term “module” will mean (unital) right module over a ring (associative with 1) R The category of these is denoted Mod-R, the full subcategory of finitely presented modules will be denoted mod-R, the notation R-Mod denotes the category of left R-modules By Ab we mean the category of Abelian groups In Part 1 we introduce the general concepts and in Part 2 we discuss these in more specific contexts References within the text, as well as those in the bibliography, are not comprehensive but are intended to lead the reader to a variety of sources

A systematic asymmetry in the polarization properties of double radio sources with one jet

Abstract: It has long been a puzzle why high-luminosity extragalactic radio sources, which are symmetric in many respects, have jets on one side only1.The jets may be intrinsically asymmetric, because dissipation is stronger on one side or because they flip alternately between the two lobes they supply2, or the one-sidedness may be only apparent, the result of Doppler beaming in twin relativistic jets3. So far, attempts to distinguish observationally between these two possibilities have been inconclusive4. Following a suggestion by Laing5, we report here new observations which establish that almost invariably the jet side depolarizes less rapidly with increasing wavelength than the opposite side. If the jet one-sidedness is intrinsic, this depolarization most probably occurs internally, but if the one-sidedness is due to Doppler beaming the depolarization must occur in a foreground screen. Further detailed polarization observations, which can determine whether the depolarization in such sources is internal or external, should therefore settle whether jets are intrinsically or only apparently one-sided.

Collaborative coefficient: A single measure of the degree of collaboration in research

Abstract: It is shown that the mean number of authors per paper or the proportion of the multiple-authored papers is inadequate as a measure of the degree of collaboration in a discipline. A measure which combines some of the merits of both measures is suggested and derived. This measure, called the Collaborative Coefficient, is derived for four commonly used probability distributions.

Visual working memory in young-children

Abstract: Five experiments investigated immediate memory for drawings of familiar objects in children of different ages. The aims were to demonstrate younger children’s greater dependence on visual working memory and to explore the nature of this memory system. Experiment 1 showed that visual similarity of drawings impaired recall in young (5-year-old) children but not in older (10-year-old) children. Experiment 2 showed that younger and older children were affected in contrasting ways when the temporal order of recall was manipulated. Experiment 3 explored a recency effect found in backward recall and investigated its sensitivity to the presentation modality of materials used to produce retroactive interference (RI). For younger children, recency was reduced by visual but not by auditory-verbal RI; for older children, recency was more sensitive to auditoryverbal RI. Experiment 4 confirmed the effect of visual RI on visual recency in young children and showed that the same RI had little effect on their recall of spoken words. These results confirm younger children’s dependence on visual working memory. A final experiment showed that the effects of visual similarity and visual RI are additive, suggesting that they reflect different modes of accessing stored visuospatial information. Implications of these findings for developmental issues and for the nature of visual working memory are discussed.

Alzheimer's disease and Down's syndrome.

Abstract: The neuropathology of Down's syndrome at middle age is compared with that of Alzheimer's disease at that age, through a review of the published literature and from the author's personal observations. The pathological changes of Down's syndrome at middle age, i.e. the form and distribution of senile plaques and neurofibrillary tangles, and the pattern of involvement (atrophy) of neuronal systems are qualitatively the same as those of Alzheimer's disease at that age. Quantitative differences do occur and these may relate to biological or sociological variations inherent to the two parent populations. It is concluded that, in pathological terms, patients with Down's syndrome at middle age do indeed have Alzheimer's disease. Some ways in which a study of patients with Down's syndrome can give insight into the nature and development of the pathological changes of Alzheimer's disease are put forward and discussed.

An immunohistochemical study of human endometrial extracellular matrix during the menstrual cycle and first trimester of pregnancy

Abstract: Changes in the organisation and composition of extracellular matrix in human endometrium during the menstrual cycle and early pregnancy have been assessed by immunofluorescence. Amongst interstitial components, type-III and type V-collagens and fibronectin are present in endometrial stroma throughout the menstrual cycle as well as in first trimester decidua. Type V-collagen epitopes are masked early in the cycle, but become accessible in first trimester decidua. Type VI-collagen is abundant in endometrium in the proliferative phase, but is progressively lost in the secretory phase and decidua, in which it is retained only in blood vessel walls. Vitronectin is present in some blood vessels in decidua. Decidualising stromal cells also produce basement membrane components (type IV-collagen, laminin, heparan sulphate proteoglycan and a glycoprotein family recognised by monoclonal antibody G71) and these become organised into a pericellular aura.

Infrared spectroscopy of dust in the Taurus dark clouds: ice and silicates

Abstract: Des spectres IR representant les caracteristiques de la poussiere pour la glace a 3 μm et le silicate a 10 μm sont presentes pour des etoiles en direction du complexe de nuages sombres Taurus, l'echantillon observe incluant des etoiles de champ vues a travers le nuage et des objets presents dans l'environnement poussiereux des nuages Le resultat principal de l'etude demontre une correlation lineaire remarquable entre l'extinction visuelle Av et la profondeur optique dans la caracteristique d'absorption 3 μm de la glace pour les etoiles de champ vues a travers le nuage Par contraste, la caracteristique d'absorption a 97 μm du silicate est faiblement correlee avec Av, refletant une dilution de l'absorption du silicate relativement a Av resultant de la croissance des manteaux moleculaires dans le nuage sombre

Spatially restricted domains of homeo-gene transcripts in mouse embryos: relation to a segmented body plan

Abstract: Note: Gaunt, Sj Afrc,Inst Anim Physiol & Genet Res,Dept Molec Embryol,Cambridge Cb2 4at,England Fac Med Strasbourg,Cnrs,Genet Molec Eucaryotes Lab,Inserm,U184,F-67085 Strasbourg,France Univ Manchester,Dept Cell & Struct Biol,Manchester M13 9Pt,Lancs,England Reference UPDUB-ARTICLE-1988-002 Record created on 2008-02-25, modified on 2017-05-12

Cytokines in synovial fluid: II. The presence of tumour necrosis factor and interferon.

Abstract: Cytokine-specific monoclonal antibodies were used in enzyme-linked immunoadsorbant assays (ELISA) to examine a variety of synovial fluids for the presence of cytokines which might be expected to play some part in the pathology of arthritis. Low, but significant, levels of tumour necrosis factor alpha (TNF-alpha) were present in the majority of synovial fluids obtained from rheumatoid arthritis patients with a sero-positive history. Low levels of interferon (IFN)-alpha and IFN-gamma were also detected, but only IFN-alpha was significantly increased in the sero-positive group. Tumour necrosis factor beta (TNF-beta) was present only in trace amounts. These results suggest that the presence of cytokines, such as TNF-alpha and IFN-alpha in synovial fluid may be associated with tissue changes observed in rheumatoid joint disease and thus contribute to the pathology of the arthritis, but support evidence for the minimal role likely to be played by IFN-gamma in the joint pathology of rheumatoid arthritis.

Comparison of delayed release 5 aminosalicylic acid (mesalazine) and sulphasalazine in the treatment of mild to moderate ulcerative colitis relapse.

Abstract: Oral formulations of 5-aminosalicylic acid (mesalazine) appear less toxic than sulphasalazine. We have therefore compared sulphasalazine, low dose mesalazine and high dose mesalazine in the treatment of mild to moderate relapse of ulcerative colitis. Sixty one patients (32 men, aged 20-78 years) were randomly allocated to sulphasalazine 2 g daily, mesalazine 800 mg daily, or mesalazine 2.4 g daily in a double blind, double dummy, four week trial. Groups were comparable for age, sex, extent of disease, and pretrial sulphasalazine intake. Four patients were unable to complete the study because of treatment failure (two taking sulphasalazine and two high dose mesalazine). A further two patients taking sulphasalazine developed side effects necessitating withdrawal. Within treatment comparisons revealed significant improvement of: sigmoidoscopic grade in the sulphasalazine group; rectal bleeding, sigmoidoscopic and histological grade in the low dose mesalazine group; stool frequency, rectal bleeding and sigmoidoscopic grade in the high dose mesalazine group. Greater improvement in rectal bleeding (p less than 0.05) and sigmoidoscopic appearances (p less than 0.05) occurred in patients taking high dose mesalazine than in those taking sulphasalazine. In two patients taking high dose mesalazine minor rises of plasma creatinine concentrations occurred, suggesting the need to monitor renal function.

Disposition in male volunteers of a subanaesthetic intravenous dose of an oil in water emulsion of 14C-propofol.

Abstract: 1. An intravenous dose of 14C-propofol (0.47 mg/kg) administered to six male volunteers was rapidly eliminated with 88% recovered in the urine in 5 days and less than 2% in faeces. 2. The dose was cleared by metabolism with less than 0.3% excreted unchanged. The major metabolites were the glucuronic acid conjugate of propofol and the glucuronic acid and sulphate conjugates of its hydroxylated derivative, 2,6-diisopropyl-1,4-quinol. Propofol glucuronide accounted for about 53% of the urinary radioactivity and was the major metabolite in plasma from 30 min post dose. 3. The blood concentration of propofol declined in a biphasic manner from a maximum mean value of 0.44 microgram/ml, 2 min after injection. The half-lives of the first and second exponential phases, mean values 5 min and 97 min respectively, varied widely among subjects. A proportion of the dose was cleared slowly, probably due to slow release from less well perfused tissues. Propofol accounted for 94% of the total blood radioactivity at 2 min but only about 6% from 3 to 8 h post dose. 4. Propofol has a volume of distribution equivalent to about 3 to 4 times body weight, and a mean total body clearance of 2.2 1/min.

Constraint programming languages: their specification and generation

Abstract: Interestingly, constraint programming languages their specification and generation that you really wait for now is coming. It's significant to wait for the representative and beneficial books to read. Every book that is provided in better way and utterance will be expected by many peoples. Even you are a good reader or not, feeling to read this book will always appear when you find it. But, when you feel hard to find it as yours, what to do? Borrow to your friends and don't know when to give back it to her or him.

Computational nuclear physics

Abstract: Details of the link between relativistic quantum field theories and low-energy hadronic physics are still uncertain and hence nuclear physics is still without a firm theoretical foundation. Nevertheless it is a mature science in which the mathematical models have grown in sophistication to the point where, in order to extract detailed predictions, significant computational problems must be faced. The author outlines the nature of the basic interacting neutron-proton model of nuclear physics and describes how an approximate mean-field description of the ground state may be obtained starting from a knowledge of the two-nucleon interaction. The natural extension of this mean-field theory to nuclear spectroscopy leads to the shell model and in nuclear collisions to the coupled reaction channels for light-ion collisions and the time-dependent Hartree-Fock description of heavy-ion collisions. The author concludes with some observations on the computer requirements of nuclear physics and how these might develop in the near future.

Cytokines in synovial fluid. I. The presence of biologically active and immunoreactive IL-1.

Abstract: Using a sensitive IL-1-dependent T cell clone we estimated interleukin 1 (IL-1)-like activity in a variety of synovial fluids (SF). Although we demonstrate that SF contains potent inhibitors of endogenous and exogenous IL-1 we were able to estimate that samples from rheumatoid arthritis, osteoarthritis and other arthritides contain the equivalent of tens or hundreds of picograms of IL-1 per millilitre, when compared to a standard IL-1 preparation. Although there was some correlation between these results and those obtained using a radio-immunoassay (RIA) for IL-1 beta, the RIA indicated that IL-1 was present in the nanogram range. The results suggest that the importance of inhibitors of IL-1 in SF merits particular attention and that it is also important to consider the bioactivity of cytokines which may be detected by physical methods.