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General Aspects (general + aspect)
Selected AbstractsGastrointestinal Regulation of Food Intake: General Aspects and Focus on Anandamide and OleoylethanolamideJOURNAL OF NEUROENDOCRINOLOGY, Issue 2008R. Capasso The gastrointestinal tract plays a pivotal role in the regulation of food intake and energy balance. Signals from the gastrointestinal tract generally function to limit ingestion in the interest of efficient digestion. These signals may be released into the bloodstream or may activate afferent neurones that carry information to the brain and its cognitive centres, which regulates food intake. The rate at which nutrients become systemically available is also influenced by gastrointestinal motility: a delay in gastric emptying may evoke a satiety effect. Recent evidence suggests that the endocannabinoid anandamide and the related acylethanolamide oleoylethanolamide are produced in the intestine and might regulate feeding behaviour by engaging sensory afferent neurones that converge information to specific areas of the brain. The intestinal levels of these acylethanolamides are inversely correlated to feeding, as food deprivation increases intestinal levels of anandamide (which acts in the gut as a ,hunger signal'), while it decreases the levels of oleoylethanolamide (which acts in the gut as a ,satiety signal'). Additionally, these acylethanolamides, whose gastric levels change in response to diet-induced obesity, alter gastrointestinal motility, which might contribute to their effect on food intake and nutrient absorption. [source] Rhamnolipid Surfactants: An Update on the General Aspects of These Remarkable BiomoleculesBIOTECHNOLOGY PROGRESS, Issue 6 2005Marcia Nitschke Pseudomonas strains are able to biosynthesize rhamnose-containing surfactants also known as rhamnolipids. These surface-active compounds are reviewed with respect to chemical structure, properties, biosynthesis, and physiological role, focusing on their production and the use of low-cost substrates such as wastes from food industries as alternative carbon sources. The use of inexpensive raw materials such as agroindustrial wastes is an attractive strategy to reduce the production costs associated with biosurfactant production and, at same time, contribute to the reduction of environmental impact generated by the discard of residues, and the treatment costs. Carbohydrate-rich substrates generated low rhamnolipid levels, whereas oils and lipid-rich wastes have shown excellent potential as alternative carbon sources. [source] The ERA-40 re-analysisTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 612 2005S. M. Uppala Abstract ERA-40 is a re-analysis of meteorological observations from September 1957 to August 2002 produced by the European Centre for Medium-Range Weather Forecasts (ECMWF) in collaboration with many institutions. The observing system changed considerably over this re-analysis period, with assimilable data provided by a succession of satellite-borne instruments from the 1970s onwards, supplemented by increasing numbers of observations from aircraft, ocean-buoys and other surface platforms, but with a declining number of radiosonde ascents since the late 1980s. The observations used in ERA-40 were accumulated from many sources. The first part of this paper describes the data acquisition and the principal changes in data type and coverage over the period. It also describes the data assimilation system used for ERA-40. This benefited from many of the changes introduced into operational forecasting since the mid-1990s, when the systems used for the 15-year ECMWF re-analysis (ERA-15) and the National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) re-analysis were implemented. Several of the improvements are discussed. General aspects of the production of the analyses are also summarized. A number of results indicative of the overall performance of the data assimilation system, and implicitly of the observing system, are presented and discussed. The comparison of background (short-range) forecasts and analyses with observations, the consistency of the global mass budget, the magnitude of differences between analysis and background fields and the accuracy of medium-range forecasts run from the ERA-40 analyses are illustrated. Several results demonstrate the marked improvement that was made to the observing system for the southern hemisphere in the 1970s, particularly towards the end of the decade. In contrast, the synoptic quality of the analysis for the northern hemisphere is sufficient to provide forecasts that remain skilful well into the medium range for all years. Two particular problems are also examined: excessive precipitation over tropical oceans and a too strong Brewer-Dobson circulation, both of which are pronounced in later years. Several other aspects of the quality of the re-analyses revealed by monitoring and validation studies are summarized. Expectations that the ,second-generation' ERA-40 re-analysis would provide products that are better than those from the firstgeneration ERA-15 and NCEP/NCAR re-analyses are found to have been met in most cases. © Royal Meteorological Society, 2005. The contributions of N. A. Rayner and R. W. Saunders are Crown copyright. [source] Four cases of distinctive meningiomas with Zellballen growth patternAPMIS, Issue 12 2009YINGCHUN DONG Meningiomas are attributed to those tumours with slow-growing pattern occurring predominantly in middle-aged or elderly patients. Fifteen histological variants have been described based on the variable histomorphological features. Herein we report four cases with specific Zellballen growth pattern, giving the tumours a ,paraganglioma-like' general aspect. The diagnosis of meningiomas was confirmed by immunohistochemical and ultrastructural findings. Histopathologists should be aware of this specific morphology which can lead to misdiagnosis. [source] Reciprocal chemokine receptor and ligand expression in the human placenta: Implications for cytotrophoblast differentiationDEVELOPMENTAL DYNAMICS, Issue 4 2004Penelope M. Drake Abstract At the onset of pregnancy, the human placenta, which forms the interface between the embryo/fetus and the mother, must rapidly develop into a life-sustaining organ. The many unusual processes entailed in placental development include the poorly understood phenomenon of maternal tolerance of the hemiallogeneic cells of the conceptus, including, most remarkably, placental trophoblasts that invade the uterine wall. To investigate whether this fetal organ exerts control over the maternal immune system at the level of leukocyte trafficking, we examined placental expression of chemokines, well-known cytokine regulators of leukocyte movements. In situ hybridization revealed abundant expression of 13 chemokines in the stromal but not the trophoblast compartment of chorionic villi. Potential roles for these molecules include recruitment of the resident macrophage (Hofbauer cell) population to the villi. In parallel, cytotrophoblast production of a panel of nine chemokine receptors was assessed by using RNase protection assays. The numerous receptors detected suggested the novel possibility that the paracrine actions of chemokine ligands derived from either the villous stroma or the decidua could mediate general aspects of placental development, with specific contributions to cytotrophoblast differentiation along the pathway that leads to uterine invasion. Developmental Dynamics 229:877,885, 2004. © 2004 Wiley-Liss, Inc. [source] REVIEW: Human and laboratory rodent low response to alcohol: is better consilience possible?ADDICTION BIOLOGY, Issue 2 2010John C. Crabbe ABSTRACT If people are brought into the laboratory and given alcohol, there are pronounced differences among individuals in many responses to the drug. Some participants in alcohol challenge protocols show a cluster of ,low level of responses to alcohol' determined by observing post-drinking-related changes in subjective, motor and physiological effects at a given dose level. Those individuals characterized as having low level of response (LR) to alcohol have been shown to be at increased risk for a lifetime diagnosis of alcohol dependence (AD), and this relationship between low LR and AD appears to be in part genetic. LR to alcohol is an area where achieving greater consilience between the human and the rodent phenotypes would seem to be highly likely. However, despite extensive data from both human and rodent studies, few attempts have been made to evaluate the human and animal data systematically in order to understand which aspects of LR appear to be most directly comparable across species and thus the most promising for further study. We review four general aspects of LR that could be compared between humans and laboratory animals: (1) behavioral measures of subjective intoxication; (2) body sway; (3) endocrine responses; and (4) stimulant, autonomic and electrophysiological responses. None of these aspects of LR provide completely face-valid direct comparisons across species. Nevertheless, one of the most replicated findings in humans is the low subjective response, but, as it may reflect either aversively valenced and/or positively valenced responses to alcohol as usually assessed, it is unclear which rodent responses are analogous. Stimulated heart rate appears to be consistent in animal and human studies, although at-risk subjects appear to be more rather than less sensitive to alcohol using this measure. The hormone and electrophysiological data offer strong possibilities of understanding the neurobiological mechanisms, but the rodent data in particular are rather sparse and unsystematic. Therefore, we suggest that more effort is still needed to collect data using refined measures designed to be more directly comparable in humans and animals. Additionally, the genetically mediated mechanisms underlying this endophenotype need to be characterized further across species. [source] Maximum Residue Limits of Veterinary Medicinal Products and Their Regulation in European Community LawEUROPEAN LAW JOURNAL, Issue 2 2003Robert Ancuceanu This paper proposes a legal analysis of a legal and empirical tool (maximum residue limits (MRLs)) designed to protect the consumers of animal foodstuffs, as it is regulated in European Community law. After introducing the concept of MRLs in its legal context, MRLs are defined and the need for harmonisation in this field is explained. Then the main rules governing the establishment of MRLs at a Europe-wide level are expounded, an important place being devoted to some problems occurred in the cases decided by the European Court of Justice: is it possible to establish an MRL only for certain therapeutic indications? What about the intention of placing on the market in the establishment of an MRL? Is the procedure for the establishment of MRLs a tight or lax one? The answer to some of these questions involves more general aspects of European Community law. [source] Beliefs of chronically ill Japanese patients that lead to intentional non-adherence to medicationJOURNAL OF CLINICAL PHARMACY & THERAPEUTICS, Issue 5 2004N. Iihara BS Summary Objective:, To identify factors, associated with personal beliefs, involved in intentional non-adherence to prescribed medication of Japanese patients with chronic diseases. Methods:, A cross-sectional study of Japanese subjects with chronic, primarily liver, gastrointestinal, or nervous system diseases who had been prescribed oral medicines for regular use, was performed. The subjects were admitted to a university hospital and were interviewed face-to-face on admission. Intentional non-adherence was defined as experience of deliberate adjustment of self-managed prescription medicines during the few months prior to hospital admission. Patients' beliefs about taking medicines were assessed from the perspective of what the patient valued in order to take medicines without anxiety; whether the patient valued information about the medication such as its function and side-effects and/or mutual reliance on doctors. Using logistic multivariate regression analyses, factors associated with intentional non-adherence were identified. Results:, Among 154 subjects, 51 showed intentional non-adherence. Intentional non-adherence was associated with the following three factors: (a) the patients' beliefs with respect to taking medicines without anxiety, especially putting no value on mutual reliance on the patient,doctor relationship (P < 0·001) and putting great value on knowing the drug's side-effects (P < 0·001), (b) poor comprehension of general aspects of medication (P for trend <0·001), and (c) being in the prime of life (40,59 years) (P = 0·011). Comprehension of the function of each medicine, experience of side-effects, anxiety about taking medicines, and the number of types of medicines taken, were not associated with non-adherence. Conclusions:, Beliefs on which individual Japanese patients with chronic diseases attach value in order to take medicines without anxiety were potential factors for intentional non-adherence. This emphasizes the necessity of a patient-oriented approach to take account of patients' personal beliefs about medicines to increase adherence rate in Japan. [source] A general model of the public goods dilemmaJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 6 2010S. A. Frank Abstract An individually costly act that benefits all group members is a public good. Natural selection favours individual contribution to public goods only when some benefit to the individual offsets the cost of contribution. Problems of sex ratio, parasite virulence, microbial metabolism, punishment of noncooperators, and nearly all aspects of sociality have been analysed as public goods shaped by kin and group selection. Here, I develop two general aspects of the public goods problem that have received relatively little attention. First, variation in individual resources favours selfish individuals to vary their allocation to public goods. Those individuals better endowed contribute their excess resources to public benefit, whereas those individuals with fewer resources contribute less to the public good. Thus, purely selfish behaviour causes individuals to stratify into upper classes that contribute greatly to public benefit and social cohesion and to lower classes that contribute little to the public good. Second, if group success absolutely requires production of the public good, then the pressure favouring production is relatively high. By contrast, if group success depends weakly on the public good, then the pressure favouring production is relatively weak. Stated in this way, it is obvious that the role of baseline success is important. However, discussions of public goods problems sometimes fail to emphasize this point sufficiently. The models here suggest simple tests for the roles of resource variation and baseline success. Given the widespread importance of public goods, better models and tests would greatly deepen our understanding of many processes in biology and sociality. [source] 14-3-3 Proteins in Pineal Photoneuroendocrine Transduction: How Many Roles?JOURNAL OF NEUROENDOCRINOLOGY, Issue 4 2003D. C. Klein Abstract Recent studies suggest that a common theme links the diverse elements of pineal photoneuroendocrine transduction ,regulation via binding to 14-3-3 proteins. The elements include photoreception, neurotransmission, signal transduction and the synthesis of melatonin from tryptophan. We review general aspects of 14-3-3 proteins and their biological function as binding partners, and also focus on their roles in pineal photoneuroendocrine transduction. [source] The epithelial cell rests of Malassez , a role in periodontal regeneration?JOURNAL OF PERIODONTAL RESEARCH, Issue 4 2006J. C. Rincon This article reviews general aspects about the epithelial cell rests of Malassez (ERM). The historical and general morphological features of the ERM are briefly described. The embryological derivation of the ERM is presented as an important consideration in understanding the events associated with their origin and possible functional roles within the periodontal ligament. The ultrastructural description of the ERM is also included to complement the morphological characteristics which distinguish these cells as the unique epithelial element of the periodontal ligament. The unique ability of these cells to synthesize and secrete a number of proteins usually associated with cells of mesenchymal origin, rather than ectodermal origin, is discussed in light of their role in cementum repair and regeneration. Such considerations lead to our hypothesis that one of the functional roles of the ERM may lie not only their role in maintaining and contributing to the normal periodontal cellular elements and function but also contributing, in a significant manner, to periodontal regeneration. [source] Scaling characteristics and growth of corrosion product films in turbulent flow solution containing saturated CO2MATERIALS AND CORROSION/WERKSTOFFE UND KORROSION, Issue 1 2009Z. F. Yin Abstract In the present study, the surface and cross-section microstructures of the corrosion films were investigated by SEM and the corrosion rate was measured by mass loss at the various conditions associated with the main influencing factors such as temperature, CO2 partial pressure, and flow velocity. The results indicated that the three factors have obvious characteristics and the enhanced interactions among the main influencing factors intensively influence the formation and growth of corrosion film. In addition, there were two corrosion mechanisms connected with the forming film and damaging film. A new lattice model was proposed to describe the general aspects concerning the formation of the corrosion film at the metal surface/solution interfaces. [source] Diabetes mellitus and the peripheral nervous system: Manifestations and mechanisms,MUSCLE AND NERVE, Issue 2 2007Douglas W. Zochodne MD Abstract Diabetes targets the peripheral nervous system with several different patterns of damage and several mechanisms of disease. Diabetic polyneuropathy (DPN) is a common disorder involving a large proportion of diabetic patients, yet its pathophysiology is controversial. Mechanisms considered have included polyol flux, microangiopathy, oxidative stress, abnormal signaling from advanced glycation endproducts and growth factor deficiency. Although some clinical trials have demonstrated modest benefits in disease stabilization or pain therapy in DPN, robust therapy capable of reversing the disease is unavailable. In this review, general aspects of DPN and other diabetic neuropathies are examined, including a summary of recent therapeutic trials. A particular emphasis is placed on the evidence that the neurobiology of DPN reflects a unique yet common and disabling neurodegenerative disorder. Muscle Nerve, 2007 [source] General theory of domain decomposition: Beyond Schwarz methodsNUMERICAL METHODS FOR PARTIAL DIFFERENTIAL EQUATIONS, Issue 5 2001Ismael Herrera Abstract Recently, Herrera presented a general theory of domain decomposition methods (DDM). This article is part of a line of research devoted to its further development and applications. According to it, DDM are classified into direct and indirect, which in turn can be subdivided into overlapping and nonoverlapping. Some articles dealing with general aspects of the theory and with indirect (Trefftz,Herrera) methods have been published. In the present article, a very general direct-overlapping method, which subsumes Schwarz methods, is introduced. Also, this direct-overlapping method is quite suitable for parallel implementation. © 2001 John Wiley & Sons, Inc. Numer Methods Partial Differential Eq 17: 495,517, 2001 [source] A strategy for supervising occupational therapy students at community sitesOCCUPATIONAL THERAPY INTERNATIONAL, Issue 1 2005Susan Mulholland Academic Coordinator of Clinical Education Abstract Within the field of occupational therapy various innovative strategies have been used to provide students with effective clinical education (fieldwork) opportunities. One of the more unusual strategies involves the student participating in a placement at a site where there is no occupational therapist and no well-defined role. The University of Alberta, Canada developed and piloted a new fieldwork supervisory position. Feedback was collected from both the sites and students to explore the impact of this position on the fieldwork experience for stakeholders. As well, sites and students were asked to give their opinions on more general aspects of these placements. Both sites and students positively endorsed the fieldwork educator for independent community placement's role. Most recommendations for improvement revolved around increasing the time dedicated to this position and making it permanent. Caution must be taken in generalizing the results of this study, as there may be various considerations that make this an appropriate supervision strategy in Alberta, Canada but not in other locations. Further research is required to determine whether this supervision strategy could be used with other students or professions in other locations. Copyright © 2005 Whurr Publishers Ltd. [source] Practitioner Review: Use of antiepileptic drugs in childrenTHE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 2 2006Renzo Guerrini Background:, The aim in treating epilepsy is to minimise or control seizures with full respect of quality-of-life issues, especially of cognitive functions. Optimal treatment first demands a correct recognition of the major type of seizures, followed by a correct diagnosis of the type of epilepsy or of the specific syndrome. Methods:, Review of data from literature and personal clinical experience in treating children with epilepsy. Results:, After summarising the general aspects on the diagnosis and treatment of the main forms of childhood epilepsy, we review key issues about management of seizure disorders, including when to start treatment, how to proceed when the first treatment fails, and how to set the targets of treatment. A special section is devoted to the new concept of epileptic encephalopathy and to the influence of ,interictal' EEG abnormalities on cognition, behaviour, and motor abilities in children, providing some suggestions on why and how to treat these conditions. A second section approaches the choice of treatment according to the specific syndromes including infantile spasms, focal epilepsies, syndromes with typical absence seizures, the myoclonic epilepsies and the Lennox,Gastaut syndrome. Conclusions:, Antiepileptic drugs (AEDs) can efficiently control seizures in most children. However, the specificity of AEDs is relatively limited, although continuing research is leading to a better understanding of the relationship between pathogenesis and the mechanism(s) and site(s) of drug action. [source] The decline of Magan and the rise of Dilmun: Umm an-Nar ceramics from the burial mounds of Bahrain, c.2250,2000 BCARABIAN ARCHAEOLOGY AND EPIGRAPHY, Issue 2 2009Steffen Terp Laursen This article outlines some general aspects of the Magan and Dilmun trade and goes on to examine the Umm an-Nar pottery discovered in the tombs of the Early Dilmun burial mounds of Bahrain. These ceramics are of particular interest because they indirectly testify to Dilmun's contact with Magan in the late third millennium. In this article, thirty vessels of seven morphological types are singled out. By comparison with the material published from the Oman peninsula the Bahrain collection is tentatively dated to c.2250,2000 BC. The location of the Umm an-Nar pottery within the distribution of burial mounds reveals that its import was strongly associated with the scattered mounds of Early Type. It is demonstrated that the frequency of Umm an-Nar pottery declined just as the ten compact cemeteries emerged c.2050 BC. The observed patterns are seen as a response to the decline of Magan and the rise of Dilmun. [source] Validity and clinical significance of biomechanical testing of implant/bone interfaceCLINICAL ORAL IMPLANTS RESEARCH, Issue S2 2006Carlos Aparicio Abstract Purpose: The aim of this paper was to review the clinical literature on the Resonance frequency analysis (RFA) and Periotest techniques in order to assess the validity and prognostic value of each technique to detect implants at risk for failure. Material and methods: A search was made using the PubMed database to find clinical studies using the RFA and/or Periotest techniques. Results: A limited number of clinical reports were found. No randomized-controlled clinical trials or prospective cohort studies could be found for validity testing of the techniques. Consequently, only a narrative review was prepared to cover general aspects of the techniques, factors influencing measurements and the clinical relevance of the techniques. Conclusions: Factors such as bone density, upper or lower jaw, abutment length and supracrestal implant length seem to influence both RFA and Periotest measurements. Data suggest that high RFA and low Periotest values indicate successfully integrated implants and that low/decreasing RFA and high/increasing Periotest values may be signs of ongoing disintegration and/or marginal bone loss. However, single readings using any of the techniques are of limited clinical value. The prognostic value of the RFA and Periotest techniques in predicting loss of implant stability has yet to be established in prospective clinical studies. [source] | ||||||||||||||||