Showing papers by "University of Gothenburg published in 2000"

Effects of Controlled-Release Metoprolol on Total Mortality, Hospitalizations, and Well-being in Patients With Heart Failure: The Metoprolol CR/XL Randomized Intervention Trial in Congestive Heart Failure (MERIT-HF)

Abstract: For editorial comment see p 1335. Context Results from recent studies on the effects of b1-blockade in patients with heart failure demonstrated a 34% reduction in total mortality. However, the effect of b1-blockade on the frequency of hospitalizations, symptoms, and quality of life in patients with heart failure has not been fully explored. Objective To examine the effects of the b1-blocker controlled-release/extendedrelease metoprolol succinate (metoprolol CR/XL) on mortality, hospitalization, symptoms, and quality of life in patients with heart failure.

Functional and clinical significance of skeletal muscle architecture.

Abstract: Skeletal muscle architecture is the structural property of whole muscles that dominates their function. This review describes the basic architectural properties of human upper and lower extremity muscles. The designs of various muscle groups in humans and other species are analyzed from the point of view of optimizing function. Muscle fiber arrangement and motor unit arrangement is discussed in terms of the control of movement. Finally, the ability of muscles to change their architecture in response to immobilization, eccentric exercise, and surgical tendon transfer is reviewed. Future integrative physiological studies will provide insights into the mechanisms by which such adaptations occur. It is likely that muscle fibers transduce both stress and strain and respond by modifying sarcomere number in a way more suited to the new biomechanical environment.

Peripheral infusion of IGF-I selectively induces neurogenesis in the adult rat hippocampus.

Abstract: In several species, including humans, the dentate granule cell layer (GCL) of the hippocampus exhibits neurogenesis throughout adult life. The ability to regulate adult neurogenesis pharmacologically may be of therapeutic value as a mechanism for replacing lost neurons. Insulin-like growth factor-I (IGF-I) is a growth-promoting peptide hormone that has been shown to have neurotrophic properties. The relationship between IGF-I and adult hippocampal neurogenesis is to date unknown. The aim of this study was to investigate the effect of the peripheral administration of IGF-I on cellular proliferation in the dentate subgranular proliferative zone, which contains neuronal progenitor cells, and on the subsequent migration and differentiation of progenitor cells within the GCL. Using bromodeoxyuridine (BrdU) labeling, we found a significant increase of BrdU-immunoreactive progenitors in the GCL after 6 d of peripheral IGF-I administration. To determine the cell fate in progenitor progeny, we characterized the colocalization of BrdU-immunolabeled cells with cell-specific markers. In animals treated with IGF-I for 20 d, BrdU-positive cells increased significantly. Furthermore, the fraction of newly generated neurons in the GCL increased, as evaluated by the neuronal markers Calbindin D(28K), microtubule-associated protein-2, and NeuN. There was no difference in the fraction of newly generated astrocytes. Thus, our results show that peripheral infusion of IGF-I increases progenitor cell proliferation and selectively induces neurogenesis in the progeny of adult neural progenitor cells. This corresponds to a 78 +/- 17% (p < 0.001) increase in the number of new neurons in IGF-I-treated animals compared with controls.

Research criteria for subcortical vascular dementia in clinical trials.

Abstract: Vascular dementia (VaD) incorporate different vascular mechanisms and changes in the brain, and have different causes and clinical manifestations. Variation in defining the cognitive syndrome, in vascular etiologies, and allowable brain changes in current clinical definitions of VaD have resulted in variable estimates of prevalence, of groups of subjects, and of the types and distribution of putative causal brain lesions. Thus current criteria for VaD select an etiologically and clinically heterogeneous group. This definitional heterogeneity may have been a factor in “negative” clinical trials. An alternative for clinical drug trials is to focus on a more homogenous group, such as those with subcortical (ischemic) VaD. This designation incorporates two small vessel clinical entities “Binswanger’s disease” and “the lacunar state”. It comprises small vessel disease as the primary vascular etiology, lacunar infarct(s) and ischaemic white matter lesions as the primary type of brain lesions, and subcortical location as the primary location of lesions. The subcortical clinical syndrome is the primary clinical manifestation, a definition which still requires additional empirical data. We expect that subcortical VaD show a more predictable clinical picture, natural history, outcome, and treatment responses. We propose a modification of the NINDS-AIREN criteria as a new research criteria for subcortical VaD.

Information state and dialogue management in the TRINDI dialogue move engine toolkit

Abstract: We introduce an architecture and toolkit for building dialogue managers currently being developed in the TRINDI project, based on the notions of information state and dialogue move engine. The aim is to provide a framework for experimenting with implementations of different theories of information state, information state update and dialogue control. A number of dialogue managers are currently being built using the toolkit, and we present overviews of two of them. We believe that this framework will make implementation of dialogue processing theories easier, also facilitating comparison of different types of dialogue systems, thus helping to achieve a prerequisite for arriving at a best practice for the development of the dialogue management component of a spoken dialogue system.

Autism and Asperger syndrome: coexistence with other clinical disorders

Abstract: Objective: To provide a clinically useful analysis of the extent to which autism and Asperger syndrome coexist with other disorders. Method: Selective review of the literature detailing data pertaining to symptoms and disorders sometimes encountered in connection with autism or Asperger syndrome. Results: A large number of medical conditions, psychiatric disorders and behavioural and motor dyscontrol symptoms are associated with autism and Asperger syndrome. Conclusion: Comorbidity is to be expected in autism spectrum disorders — directly or indirectly. Comorbid conditions may be markers for underlying pathophysiology and suggest a more varied treatment approach. There is a great need for in-depth research into this area, meaning that the exclusion criteria of current diagnostic manuals, i.e. those that rule out a diagnosis of autism in some disorders, and a diagnosis of certain other disorders in autism may have to be revised.

Increased gibberellin biosynthesis in transgenic trees promotes growth, biomass production and xylem fiber length.

Abstract: In most tree-breeding programs worldwide, increasing the trees' growth rates and stem volumes and shortening their rotation times are important aims. Such trees would yield more biomass per unit area. Here we show that overexpressing a key regulatory gene in the biosynthesis of the plant hormone gibberellin (GA) in hybrid aspen (Populus tremula x P. tremuloides) improves growth rate and biomass. In addition, these transgenic trees have more numerous and longer xylem fibers than unmodified wild-type (wt) plants. Long fibers are desirable in the production of strong paper, but it has not as yet proved possible to influence this trait by traditional breeding techniques. We also show that GA has an antagonistic effect on root initiation, as the transgenic lines showed poorer rooting than the control plants when potted in soil. However, the negative effect on rooting efficiencies in the initial establishment of young plantlets in the growth chamber did not significantly affect root growth at later stages.

A conceptual framework for the analysis of vulnerability in supply chains

Abstract: A conceptual framework for the analysis of vulnerability in supply chains is developed. The conceptual framework is limited to the inbound logistic flow of manufacturers. The study has been performed as a two‐step process. Step one explores the concept of vulnerability from the point of view of an inductive approach. The conceptual framework is generated and based on the empirical findings from a case study of a Swedish car manufacturer in the automotive industry. Step two is deductive in terms of testing in other industries the generated conceptual framework that originates from step one. The conceptual framework consists of two dimensions, namely categories of disturbance and sources of disturbance. Principally, categories of disturbance are divided into quantitative and qualitative disturbances. Sources of disturbance are divided into atomistic (direct) and holistic (indirect) disturbances. In addition, the specific criteria of an inbound logistic flow indicate how vulnerability in supply chains is proposed to be analysed according to the developed conceptual framework of vulnerability.

Age estimation: the state of the art in relation to the specific demands of forensic practise.

Abstract: Age estimation in cadavers, human remains and living individuals may clarify issues with significant legal and social ramifications for individuals as well as for the community. In such cases methods for estimating age should fulfil the following specific demands: (1) they must have been presented to the scientific community, as a rule by publication in peer-reviewed journals, (2) clear information concerning accuracy of age estimation by the method should be available, (3) the methods need to be sufficiently accurate and (4) in cases of age estimation in living individuals principles of medical ethics and legal regulations have to be considered. We have identified and summarized the methods that essentially fulfil these specific demands. In childhood and adolescence morphological methods based on the radiological examination of dental and skeletal development are to be recommended. In adulthood, the accuracy of most morphological methods is much reduced. Here a biochemical method based on aspartic acid racemization in dentine provides the most accurate estimates of age, followed by special morphological dental and skeletal methods. The choice of method has to take account of the individual circumstances of each case. Most methods require either the consultation of specialised and trained scientists or an adequate calibration by the “user”. Very few attempts have been made to find common standardisation, calibration and evaluation procedures or to develop means of quality assurance for methods of age estimation. Efforts in these directions are necessary to guarantee quality standards and adequate answers to the important legal and social issue of age estimation in forensic medicine.

Suggested guidelines for the topographic evaluation of implant surfaces.

Abstract: The bone anchorage components of commercially available oral implant systems differ in surface roughness by at least sixfold. Correct reporting of the surface roughness of implant systems is important, since one cannot exclude the possibility that surface roughness will influence clinical results. However, many confusing statements are found in the literature when the surface topography of implants is described. Different measuring instruments and techniques strongly influence the outcome of a topographic characterization. Furthermore, a screw-type design introduces problems for most measuring instruments. Without a standard procedure, it is generally impossible to compare values from one study with another. The aim of the present study was to suggest standards for topographic evaluation of oral implants in terms of measuring equipment, filtering process, and selection of parameters. It is suggested that the measuring instrument be able to measure all parts of a threaded implant if the investigation relates to such a design. Preferably, 3-dimensional measurements should be performed. On screw-type implants, tops, valleys, and flanks should be evaluated. At least 3 samples in a batch should be evaluated, filter size must be specified, and at least one of each height, spatial, and hybrid parameter should be presented.

Prevalence of depression and its treatment in an elderly population: the Cache County study.

Abstract: Background Previous estimates of the prevalence of geriatric depression have varied. There are few large population-based studies; most of these focused on individuals younger than 80 years. No US studies have been published since the advent of the newer antidepressant agents. Methods In 1995 through 1996, as part of a large population study, we examined the current and lifetime prevalence of depressive disorders in 4559 nondemented individuals aged 65 to 100 years. This sample represented 90% of the elderly population of Cache County, Utah. Using a modified version of the Diagnostic Interview Schedule, we ascertained past and present DSM-IV major depression, dysthymia, and subclinical depressive disorders. Medication use was determined through a structured interview and a "medicine chest inventory." Results Point prevalence of major depression was estimated at 4.4% in women and 2.7% in men ( P =.003). Other depressive syndromes were surprisingly uncommon (combined point prevalence, 1.6%). Among subjects with current major depression, 35.7% were taking an antidepressant (mostly selective serotonin reuptake inhibitors) and 27.4% a sedative/hypnotic. The current prevalence of major depression did not change appreciably with age. Estimated lifetime prevalence of major depression was 20.4% in women and 9.6% in men ( P Conclusions These estimates for prevalence of major depression are higher than those reported previously in North American studies. Treatment with antidepressants was more common than reported previously, but was still lacking in most individuals with major depression. The prevalence of subsyndromal depressive symptoms was low, possibly because of unusual characteristics of the population.

The Project of Rationalization: A Critique and Reappraisal of Neo-Institutionalism in Organization Studies:

Abstract: This article critically approaches various neo-institutional accounts of the process of formal organizing. While acknowledging the importance of the overall orientation marked by neo-institutional studies, the article identifies several crucial aspects that have escaped the attention of neo-institutional research. In particular, it criticizes the inability of neo-institutionalism to provide an account of the means linking situated forms of organizing with wider instrumental beliefs and practices, in terms other than adaptivist, diffusionist. Such a limitation is partly a consequence of unwillingness of neo-institutionalism to focus on and analyze the very architecture of the rationalized patterns and relationships which neo-institutionalists claim to be diffusing across organizational populations and fields. Drawing on several sources, the article develops a framework that seeks to outline the conceptual means for decomposing the carriers of rationalized patterns, models and techniques and showing the dis...

Epidemic of coeliac disease in Swedish children

Abstract: Coeliac disease has emerged as a public health problem The aim of the present study was to analyse trends in the occurrence of symptomatic coeliac disease in Swedish children from 1973 to 1997, and to explore any temporal relationship to changes in infant dietary patterns We established a population-based prospective incidence register of coeliac disease in 1991, and, in addition, retrospective data from 1973 were collected A total of 2151 cases fulfilled the diagnostic criteria Furthermore We collected national data on a yearly basis on duration of breastfeeding, intake of gluten-containing cereals and recommendations on when and how to introduce gluten into the diet of infants From 1985 to 1987 the annual incidence rate in children below 2 y of age increased fourfold to 200-240 cases per 100000 person years, followed from 1995 by a sharp decline to the previous level of 50-60 cases per 100000 person years This epidemic pattern is quite unique for a chronic disease of immunological pathogenesis, suggesting that prevention could be possible The ecological observations made in this study are compatible with the epidemic being the result, at least in part, of a change in and an interplay among three factors within the area of infant feeding, ie amount of gluten given, age at introduction of gluten, and whether breastfeeding was ongoing or not when gluten was introduced Other factor(s) may also have contributed, and the search for these should be intensified

Exploration of deep intraterrestrial microbial life: current perspectives

Abstract: Intraterrestrial life has been found at depths of several thousand metres in deep sub-sea floor sediments and in the basement crust beneath the sediments. It has also been found at up to 2800-m depth in continental sedimentary rocks, 5300-m depth in igneous rock aquifers and in fluid inclusions in ancient salt deposits from salt mines. The biomass of these intraterrestrial organisms may be equal to the total weight of all marine and terrestrial plants. The intraterrestrial microbes generally seem to be active at very low but significant rates and several investigations indicate chemolithoautotrophs to form a chemosynthetic base. Hydrogen, methane and carbon dioxide gases are continuously generated in the interior of our planet and probably constitute sustainable sources of carbon and energy for deep intraterrestrial biosphere ecosystems. Several prospective research areas are foreseen to focus on the importance of microbial communities for metabolic processes such as anaerobic utilisation of hydrocarbons and anaerobic methane oxidation.

A multiscale dynamic programming procedure for boundary detection in ultrasonic artery images

Abstract: Ultrasonic measurements of human carotid and femoral artery walls are conventionally obtained by manually tracing interfaces between tissue layers. The drawbacks of this method are the interobserver variability and inefficiency. Here, the authors present a new automated method which reduces these problems. By applying a multiscale dynamic programming (DP) algorithm, approximate vessel wall positions are first estimated in a coarse-scale image, which then guide the detection of the boundaries in a fine-scale image. In both cases, DP is used for finding a global optimum for a cost function. The cost function is a weighted sum of terms, in fuzzy expression forms, representing image features and geometrical characteristics of the vessel interfaces. The weights are adjusted by a training procedure using human expert tracings. Operator interventions, if needed, also take effect under the framework of global optimality. This reduces the amount of human intervention and, hence, variability due to subjectiveness. By incorporating human knowledge and experience, the algorithm becomes more robust. A thorough evaluation of the method in the clinical environment shows that interobserver variability is evidently decreased and so is the overall analysis time. The authors conclude that the automated procedure can replace the manual procedure and leads to an improved performance.

Protein oxidation in response to increased transcriptional or translational errors.

Abstract: In this study, we show a correlation between synthesis of aberrant proteins and their oxidative modification. The level of aberrant proteins was elevated in Escherichia coli cultures by decreasing transcriptional or translational fidelity using specific mutations or drugs. Protein carbonylation, an oxidative modification, increased in parallel to the induction of the heat shock chaperone GroEL. As the protein turnover rates and level of intracellular oxidative stress remained unchanged, it appears that carbonylation results from the increased susceptibility of the misfolded proteins. These studies show that the cellular protein oxidation is not limited only by available reactive oxygen species, but by the levels of aberrant proteins. Thus, protein oxidation seen in aging cells may be the consequence also of reduced transcriptional/translational fidelity, and protein structures appear to have evolved to minimize oxidative damage. In addition, we discuss the possibility that carbonylation, being an unrepairable protein modification, may serve as a tagging system to shunt misfolded proteins between pathways of refolding by chaperones or the proteolytic apparatus.

Gram-positive bacteria are potent inducers of monocytic interleukin-12 (IL-12) while gram-negative bacteria preferentially stimulate IL-10 production.

Abstract: Interleukin-10 (IL-10) and IL-12 are two cytokines secreted by monocytes/macrophages in response to bacterial products which have largely opposite effects on the immune system. IL-12 activates cytotoxicity and gamma interferon (IFN-gamma) secretion by T cells and NK cells, whereas IL-10 inhibits these functions. In the present study, the capacities of gram-positive and gram-negative bacteria to induce IL-10 and IL-12 were compared. Monocytes from blood donors were stimulated with UV-killed bacteria from each of seven gram-positive and seven gram-negative bacterial species representing both aerobic and anaerobic commensals and pathogens. Gram-positive bacteria induced much more IL-12 than did gram-negative bacteria (median, 3,500 versus 120 pg/ml at an optimal dose of 25 bacteria/cell; P < 0.001), whereas gram-negative bacteria preferentially stimulated secretion of IL-10 (650 versus 200 pg/ml; P < 0.001). Gram-positive species also induced stronger major histocompatibility complex class II-restricted IFN-gamma production in unfractionated blood mononuclear cells than did gram-negative species (12,000 versus 3,600 pg/ml; P < 0.001). The poor IL-12-inducing capacity of gram-negative bacteria was not remediated by addition of blocking anti-IL-10 antibodies to the cultures. No isolated bacterial component could be identified that mimicked the potent induction of IL-12 by whole gram-positive bacteria, whereas purified LPS induced IL-10. The results suggest that gram-positive bacteria induce a cytokine pattern that promotes Th1 effector functions.

Abnormal gastrointestinal development in PDGF-A and PDGFR-(alpha) deficient mice implicates a novel mesenchymal structure with putative instructive properties in villus morphogenesis.

Abstract: Development of the gastrointestinal (GI) tract depends on reciprocal epithelial-mesenchymal cell signaling. Here, we demonstrate a role for platelet-derived growth factor-A (PDGF-A) and its receptor, PDGFR-(alpha), in this process. Mice lacking PDGF-A or PDGFR-(alpha) were found to develop an abnormal GI mucosal lining, including fewer and misshapen villi and loss of pericryptal mesenchyme. Onset of villus morphogenesis correlated with the formation of clusters of PDGFR-(alpha) positive cells, 'villus clusters', which remained located at the tip of the mesenchymal core of the growing villus. Lack of PDGF-A or PDGFR-(alpha) resulted in progressive depletion of PDGFR-(alpha) positive mesenchymal cells, the formation of fewer villus clusters, and premature expression of smooth muscle actin (SMA) in the villus mesenchyme. We found that the villus clusters were postmitotic, expressed BMP-2 and BMP-4, and that their formation correlated with downregulated DNA synthesis in adjacent intestinal epithelium. We propose a model in which villus morphogenesis is initiated as a result of aggregation of PDGFR-(a) positive cells into cell clusters that subsequently function as mesenchymal centers of signaling to the epithelium. The role of PDGF-A seems to be to secure renewal of PDGFR-(alpha) positive cells when they are consumed in the initial rounds of cluster formation.

Theorising the Rise of Regionness

Abstract: (2000). Theorising the Rise of Regionness. New Political Economy: Vol. 5, No. 3, pp. 457-472.

Firm size, age and efficiency: Evidence from Kenyan manufacturing firms

Abstract: Translog stochastic frontier production functions are estimated using an unbalanced panel of 235 Kenyan manufacturing firms in the food, wood, textile and metal sectors. The sectors are estimated individually in order to investigate whether technical efficiency is systematically related to the size and age of firms. The evidence suggests that firm size has a positive and significant effect in the wood and textile sectors. The age effect is less systematic, but is insignificant in all sectors, except textiles.