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Selected AbstractsUremic pruritus: A reviewHEMODIALYSIS INTERNATIONAL, Issue 2 2005Jocemir R. Lugon Abstract Pruritus is a major disorder among the skin derangements in advanced renal failure. Its prevalence seems to be diminishing perhaps because of improvements in dialysis treatment. Recent information suggests that interactions between dermal mast cells and distal ends of nonmyelinated C fibers may be important in the precipitation and regulation of the sensory stimuli. The knowledge as to the control of pruritus transmission to cortex areas is still incomplete but endogenous opioid and opioid receptors may have a role in this regard. A recent classification was proposed for pruritus based on the level of its origin. Uremic pruritus, however, seems to be too complex to fit perfectly in any of the suggested modalities. Inflammation and malnutrition are recognized risk factors for cardiovascular death in end-stage renal disease patients, which may be related to the genesis of pruritus. Consistent with this concept, lower serum levels of albumin and higher serum levels of ferritin were found in pruritic patients when compared to nonpruritic ones. Newer treatments for this difficult clinical problem are being developed and tested. [source] Baguio Mineral District: An oceanic arc witness to the geological evolution of northern Luzon, PhilippinesISLAND ARC, Issue 4 2008Graciano P. Yumul Jr Abstract The Baguio Mineral District exposes rock formations that evince the geological and tectonic evolution of this district from a subduction-related marginal basin to an island arc setting. Available onshore and offshore data are consistent with an Early (onset phase) to Middle (developed phase) Miocene arc polarity reversal from the east (termination of subduction along the proto-East Luzon Trough) to the west (initiation of subduction along the Manila Trench). Geophysical modeling and geochemical data calculation showed a 30 ± 5 km crustal thickness for the mineral district. Subduction-related multiple arc magmatism and ophiolite accretion contributed to crustal thickening. Recent information on the Oligo,Miocene Zigzag and Klondyke formations in the mineral district reveal that the marginal basin, where these rocks were deposited, has received eroded materials from adjacent terrains characterized by siliceous lithologies. Furthermore, adakitic rocks, high permeable zones and extensional zones which are exploration markers applied to identify possible mineralization targets, are prevalent in the mineral district. The geological evolution that the district had undergone mimics the evolution of island arcs worldwide in general and northern Luzon in particular. [source] Centrifugal speciation and centres of originJOURNAL OF BIOGEOGRAPHY, Issue 5 2000John C. Briggs Abstract Aim To discuss the development and usefulness of the theory of centrifugal speciation and its practical application to the centre of origin hypothesis. Location The Indo-West Pacific Ocean. Methods Utilization of patterns demonstrating species diversity, generic age, dispersal tracks, phylogenetics, extinction and genetic diversity. Results The centrifugal speciation hypothesis appears to provide a suitable explanation for the way in which centres of origin theoretically operate. Recent information about the centre of origin in the marine East Indies suggests that it is the source of evolutionary radiation for the Indo-West Pacific. Its mechanism appears to conform to the centrifugal prediction. Main conclusions The East Indies Triangle is the origin of a series of dynamic systems that extend across the entire Indo-West Pacific. These systems are apparently maintained by a continuous outflow from the centre of origin. A series of species replacements from the East Indies over the past 10 million years would create and perpetuate the systems that have been identified. [source] Non-erosive reflux disease, functional heartburn and gastroesophageal reflux disease; insights into pathophysiology and clinical presentationJOURNAL OF DIGESTIVE DISEASES, Issue 4 2006Eamonn MM QUIGLEY Non-erosive reflux disease (NERD) has emerged as a real entity in the spectrum of gastroesophageal reflux disease (GERD) and may, indeed, represent the most common manifestation of reflux disease. Recent information indicates NERD can be further subclassified based on the results of pH studies and suggests that functional heartburn needs to be differentiated as that subgroup of patients in which there appears to be no relationship between symptoms, however ,typical' of GERD, and acid exposure. Other aspects of NERD need to be appreciated, including overlap with functional dyspepsia and the potential variations in response to such therapeutic interventions as acid-suppressive therapy and fundoplication. It seems quite possible that our failure to separate functional heartburn from NERD, in general, has contributed, in large measure, to diagnostic difficulties and therapeutic disappointment in GERD. An appreciation of the range of entities, of different etiology and pathology, within NERD will foster the development of effective approaches to the assessment and therapy of this challenging disorder. [source] The role of hepatic peroxisome proliferator-activated receptors (PPARs) in health and diseaseLIVER INTERNATIONAL, Issue 3 2000Lynn Everett Abstract: The liver has long been known to respond to exposure to certain chemicals with hyperplasia and proliferation of the peroxisomal compartment. This response is now known to be mediated by specific receptors. The peroxisome proliferator-activated receptors (PPARs) were cloned 10 years ago, and in that interval, have been found to serve as receptors for a number of endogenous lipid compounds, in addition to the peroxisome proliferators that originally led to their study. Three receptors, designated the ,, ,, and , receptors, have been found in mammals. PPAR, is the most abundant form found in the liver, with smaller amounts of the , and , forms also expressed there. Kupffer cells, like other macrophages, appear to express the , and , isoforms. Hepatic stellate cells are reported to express the , isoform. PPAR, knock-out mice fail to undergo peroxisome proliferation when challenged with the proliferators. Moreover, they have severe derangements of lipid metabolism, particularly during fasting, indicating that normal function of the alpha receptors is needed for lipid homeostasis. This in turn suggests that inadequate PPAR-mediated responses may contribute to abnormal fatty acid metabolism in alcoholic and non-alcoholic steatohepatitis. Recent information suggests that PPAR, receptors may be important in control of the activation state of the stellate cells, and their repression or inactivation may predispose to hepatic fibrosis. The first approved drug that specifically activates PPAR,, troglitazone, has rarely been found to cause serious liver injury. Although this is likely to represent an idiosyncratic reaction, the medical community will need to be alert to the possibility that activation or blockade of these receptors may cause hepatic dysfunction. [source] Opioid Rotation in the Management of Chronic Pain: Where Is the Evidence?PAIN PRACTICE, Issue 2 2010K.C.P. Vissers MD Abstract The management of chronic pain remains a challenge because of its complexity and unpredictable response to pharmacological treatment. In addition, accurate pain management may be hindered by the prejudice of physicians and patients that strong opioids, classified as step 3 medications in the World Health Organization ladder for cancer pain management, are reserved for the end stage of life. Recent information indicates the potential value of strong opioids in the treatment of chronic nonmalignant pain. There are, up until now, insufficient data to provide indications about which opioid to use to initiate treatment or the dose to be used for any specific pain syndrome. The strong inter-patient variability in opioid receptor response and in the pharmacokinetic and pharmacodynamic behavior of strong opioids justifies an individual selection of the appropriate opioid and stepwise dose titration. Clinical experience shows that switching from one opioid to another may optimize pain control while maintaining an acceptable side effect profile or even improving the side effects. This treatment strategy, described as opioid rotation or switch, requires a dose calculation for the newly started opioid. Currently, conversion tables and equianalgesic doses are available. However, those recommendations are often based on data derived from studies designed to evaluate acute pain relief, and sometimes on single dose studies, which reduces this information to the level of an indication. In daily practice, the clinician needs to titrate the optimal dose during the opioid rotation from a reduced calculated dose, based on the clinical response of the patient. Further research and studies are needed to optimize the equianalgesic dosing tables. [source] Market Shares, Financial Constraints and Pricing Behaviour in the Export MarketECONOMICA, Issue 276 2002Nils Gottfries A structural dynamic model of price and quantity adjustment is estimated on time series data for exports and export prices. Two sources of dynamics are considered: customer markets and preset prices. As predicted by the customer market model, the market share adjusts slowly after a change in the relative price and financial conditions affect prices. Prices are found to be sticky in the sense that they do not reflect the most recent information about costs and exchange rates. A parsimoniously parameterized structural model explains about 90% of the variation in market share and the relative price. [source] Structure,function studies of glutamate synthases: A class of self-regulated iron-sulfur flavoenzymes essential for nitrogen assimilationIUBMB LIFE, Issue 5 2008Maria Antonietta Vanoni Abstract Glutamate synthases play with glutamine synthetase an essential role in nitrogen assimilation processes in microorganisms, plants, and lower animals by catalyzing the net synthesis of one molecule of L -glutamate from L -glutamine and 2-oxoglutarate. They exhibit a modular architecture with a common subunit or region, which is responsible for the L -glutamine-dependent glutamate synthesis from 2-oxoglutarate. Here, a PurF- (Type II- or Ntn-) type amidotransferase domain is coupled to the synthase domain, a (,/,)8 barrel containing FMN and one [3Fe-4S]0,+1 cluster, through a ,30 Å-long intramolecular tunnel for the transfer of ammonia between the sites. In bacterial and eukaryotic GltS, reducing equivalents are provided by reduced pyridine nucleotides thanks to the stable association with a second subunit or region, which acts as a FAD-dependent NAD(P)H oxidoreductase and is responsible for the formation of the two low potential [4Fe-4S]+1,+2 clusters of the enzyme. In photosynthetic cells, reduced ferredoxin is the physiological reductant. This review focus on the mechanism of cross-activation of the synthase and glutaminase reactions in response to the bound substrates and the redox state of the enzyme cofactors, as well as on recent information on the structure of the ,, protomer of the NADPH-dependent enzyme, which sheds light on the intramolecular electron transfer pathway between the flavin cofactors. © 2008 IUBMB IUBMB Life, 60(5): 287,300, 2008 [source] Purification of Matrix Gla Protein From a Marine Teleost Fish, Argyrosomus regius: Calcified Cartilage and Not Bone as the Primary Site of MGP Accumulation in Fish,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 2 2003DC Simes Abstract Matrix Gla protein (MGP) belongs to the family of vitamin K-dependent, Gla-containing proteins, and in mammals, birds, and Xenopus, its mRNA was previously detected in extracts of bone, cartilage, and soft tissues (mainly heart and kidney), whereas the protein was found to accumulate mainly in bone. However, at that time, it was not evaluated if this accumulation originated from protein synthesized in cartilage or in bone cells because both coexist in skeletal structures of higher vertebrates and Xenopus. Later reports showed that MGP also accumulated in costal calcified cartilage as well as at sites of heart valves and arterial calcification. Interestingly, MGP was also found to accumulate in vertebra of shark, a cartilaginous fish. However, to date, no information is available on sites of MGP expression or accumulation in teleost fishes, the ancestors of terrestrial vertebrates, who have in their skeleton mineralized structures with both bone and calcified cartilage. To analyze MGP structure and function in bony fish, MGP was acid-extracted from the mineralized matrix of either bone tissue (vertebra) or calcified cartilage (branchial arches) from the bony fish, Argyrosomus regius,, separated from the mineral phase by dialysis, and purified by Sephacryl S-100 chromatography. No MGP was recovered from bone tissue, whereas a protein peak corresponding to the MGP position in this type of gel filtration was obtained from an extract of branchial arches, rich in calcified cartilage. MGP was identified by N-terminal amino acid sequence analysis, and the resulting protein sequence was used to design specific oligonucleotides suitable to amplify the corresponding DNA by a mixture of reverse transcription-polymerase chain reaction (RT-PCR) and 5,rapid amplification of cDNA (RACE)-PCR. In parallel, ArBGP (bone Gla protein, osteocalcin) was also identified in the same fish, and its complementary DNA cloned by an identical procedure. Tissue distribution/accumulation was analyzed by Northern blot, in situ hybridization, and immunohistochemistry. In mineralized tissues, the MGP gene was predominantly expressed in cartilage from branchial arches, with no expression detected in the different types of bone analyzed, whereas BGP mRNA was located in bone tissue as expected. Accordingly, the MGP protein was found to accumulate, by immunohistochemical analysis, mainly in the extracellular matrix of calcified cartilage. In soft tissues, MGP mRNA was mainly expressed in heart but in situ hybridization, indicated that cells expressing the MGP gene were located in the bulbus arteriosus and aortic wall, rich in smooth muscle and endothelial cells, whereas no expression was detected in the striated muscle myocardial fibers of the ventricle. These results show that in marine teleost fish, as in mammals, the MGP gene is expressed in cartilage, heart, and kidney tissues, but in contrast with results obtained in Xenopus and higher vertebrates, the protein does not accumulate in vertebra of non-osteocytic teleost fish, but only in calcified cartilage. In addition, our results also indicate that the presence of MGP mRNA in heart tissue is due, at least in fish, to the expression of the MGP gene in only two specific cell types, smooth muscle and endothelial cells, whereas no expression was found in the striated muscle fibers of the ventricle. In light of these results and recent information on expression of MGP gene in these same cell types in mammalian aorta, it is likely that the levels of MGP mRNA previously detected in Xenopus, birds, and mammalian heart tissue may be restricted toregions rich in smooth muscle and endothelial cells. Our results also emphasize the need to re-evaluate which cell types are involved in MGP gene expression in other soft tissues and bring further evidence that fish are a valuable model system to study MGP gene expression and regulation. [source] HIF-1 and p53: communication of transcription factors under hypoxiaJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 4 2004Tobias Schmid Abstract Oxygen sensing and reactivity to changes in the concentration of oxygen is a fundamental property of cell physiology. The lack of O2 (hypoxia) is transmitted into many adaptive responses, a process that is largely controlled by a transcription factor known as hypoxia inducible factor-1 (HIF-1). More recent reports suggest that besides its traditional regulation via proteasomal degradation other signaling pathways contribute to stability regulation of the HIF-1, subunit and/or HIF-1 transactivation. These regulatory circuits allow for the integration of HIF-1 into scenarios of cell-survival vs. cell-death with the rule of the thumb that short-term mild hypoxia maintains cell viability while prolonged and severe hypoxia provokes cell demise. Cell death pathways are associated with stabilization of the tumor suppressor p53, a response also seen under hypoxic conditions. Here we summarize recent information on accumulation of HIF-1, and p53 under hypoxia and provide a model to explain the communication between HIF-1 and p53 under (patho)physiological conditions. [source] A proposal for a dynamic h-type indexJOURNAL OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE AND TECHNOLOGY, Issue 11 2008Ronald Rousseau A time-dependent h-type indicator is proposed. This indicator depends on the size of the h-core, the number of citations received, and recent change in the value of the h-index. As such, it tries to combine in a dynamic way older information about the source (e.g., a scientist or research institute that is evaluated) with recent information. [source] Brugada Syndrome: Current Clinical Aspects and Risk StratificationANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 3 2002Ph.D., Takanori Ikeda M.D. Brugada syndrome is a primary electrical disease of the heart that causes sudden cardiac death or life-threatening ventricular arrhythmias, especially in younger men. Genetic analysis supports that this syndrome is a cardiac ion channel disease. A typical electrocardiographic finding consists of a right bundle branch block pattern and ST-segment elevation in the right precordial leads. The higher intercostal space V1 to V3 lead electrocardiogram could be helpful in detecting Brugada patients. Although two types of the ST-segment elevation are present, the coved type is more relevant to the syndrome than the saddle-back type. These patterns can be present permanently or intermittently. Recent data suggest that the Brugada-type electrocardiogram is more prevalent than the manifest Brugada syndrome. Asymptomatic individuals have a much lower incidence of future cardiac events than the symptomatic patients. Although risk stratification for the Brugada syndrome is still incomplete, the inducibility of sustained ventricular arrhythmias has been proposed as a good outcome predictor in this syndrome. In noninvasive techniques, some clinical evidence supports that late potentials detected by signal-averaged electrocardiography are a useful index for identifying patients at risk. The available data recommend prophylactic implantation of an imptantabie cardioverter defibrillator to prevent sudden cardiac death. This review summarizes recent information of the syndrome by reviewing most of new clinical reports and speculates on its risk stratification. A.N.E. 2002;7(3):251,262 [source] A review of the biophysical properties of salmonid faeces: implications for aquaculture waste dispersal models and integrated multi-trophic aquacultureAQUACULTURE RESEARCH, Issue 3 2009G K Reid Abstract Knowledge of the quantitative and qualitative properties of salmonid faeces is necessary for aquaculture waste dispersal models, and the design of integrated multi-trophic aquaculture (IMTA) systems. The amount and proximate composition of salmonid faeces can be estimated using a mass-balance, nutritional approach. Indigestible components of salmonid diets have the potential to affect faecal ,cohesiveness' or ,stability'. Nutrient content and density of faeces can vary depending on diet and submersion time. Faecal density has a greater influence on settling velocity than faecal size. Published settling velocity data on salmonid faeces are highly variable due to differences in fish size, rearing systems, collection time, water density, methodology, the mass fraction tested and diet. Most faecal settling data used in published salmonid waste dispersal models are rudimentary and recent information suggests that such models are highly sensitive to this input. The design of open-water IMTA systems and estimation of nutrient capture and recovery from co-cultured filter feeders is difficult due to limited information on particle size, digestibility, settleable and non-settleable mass fractions of salmonid faeces at cage environments. Implications of faecal properties on the accountability for the effects of aquaculture nutrient loading are discussed. [source] ADAMs in cancer cell proliferation and progressionCANCER SCIENCE, Issue 5 2007Satsuki Mochizuki A disintegrin and metalloproteinases (ADAMs) are a new gene family of proteins with sequence similarity to the reprolysin family of snake venomases that share the metalloproteinase domain with matrix metalloproteinases (MMPs). They are structurally classified into two groups: the membrane-anchored ADAM and ADAM with thrombospondin motifs (ADAMTS). These molecules are involved in various biological events such as cell adhesion, cell fusion, cell migration, membrane protein shedding and proteolysis. Studies on the biochemical characteristics and biological functions of ADAMs are in progress, and accumulated lines of evidence have shown that some ADAMs are expressed in malignant tumors and participate in the pathology of cancers. The activities of ADAMs are regulated by gene expression, intracytoplasmic and pericellular regulation, activation of the zymogens and inhibition of activities by inhibitors. Many ADAM species, including ADAM8, ADAM9, ADAM10, ADAM12, ADAM15, ADAM17, ADAM19, ADAM28, ADAMTS1, ADAMTS4 and ADAMTS5, are expressed in human malignant tumors. Many of them are involved in the regulation of growth factor activities and integrin functions, leading to promotion of cell growth and invasion, although the precise mechanisms of these are not clear at the present time. In this article, we review recent information about ADAM family members and their implications for cancer cell proliferation and progression. (Cancer Sci 2007; 98: 621,628) [source] Anosognosia for memory impairment in Alzheimer's diseaseACTA NEUROPSYCHIATRICA, Issue 4 2010Georgina Stewart Stewart G, McGeown WJ, Shanks MF, Venneri A. Anosognosia for memory impairment in Alzheimer's disease. Objective: To investigate whether patients with Alzheimer's disease (AD) were able to alter their awareness of memory deficits after exposure to a memory task. Methods: Thirty normal older adults and 23 mild AD patients participated in the study. Anosognosia was assessed using discrepancies between self- and informant-evaluations of cognitive and functional performance. Participants estimated their performance on the Verbal Paired Associates task at different points in time (before, immediately after the task and after a 1-h delay). Results: AD patients were generally less able to judge their memory abilities than healthy older adults, and tended to overestimate their task performance beforehand. Their prediction accuracy increased immediately after the task, but after a 1-h delay, they again misjudged their abilities at pretesting accuracy levels. Self-carer discrepancy scores of awareness of deficits in memory and other areas correlated significantly with memory tests but not with other neuropsychological tasks in the assessment, and larger discrepancy scores were associated with poorer performance. Conclusion: AD patients can monitor their task performance online, but are unable to maintain awareness of their deficits over time. Loss of awareness of memory deficits (or of any other deficits) in early stage AD may indicate damage to a system which updates a personal knowledge base with recent information. Failure to retain this information impedes abstraction from episodic to semantic memory. [source] Commercial and sexual exploitation of children and young people in the UK,a reviewCHILD ABUSE REVIEW, Issue 1 2005Elaine Chase Abstract This paper reviews recent information and data relevant to the commercial sexual exploitation of children and young people in the UK. Three main aspects of exploitation are addressed: abuse through prostitution; abuse through pornography; and the trafficking of children and young people to and through the UK for the purposes of commercial sexual exploitation. Most published research in this area relates to young people exploited through prostitution. The review explores the range of vulnerability factors, the processes used to engage young people in prostitution and the types of support strategies for those being exploited. Rather less information is currently available on the scale of child pornography, or the links between the use of pornography and other forms of sexual abuse. The internet as a modern technology for proliferating child pornography is discussed, alongside its role in providing opportunities for paedophiles to access and ,groom' children for sexual purposes. Finally, the review provides a summary of research on trafficking of children to and through the UK for the purposes of commercial sexual exploitation and demonstrates the limited knowledge about this topic. Copyright © 2005 John Wiley & Sons, Ltd. [source] Accelerated ventricular rhythm in the neonatal period: a review and two new cases in asymptomatic infants with an apparently normal heartACTA PAEDIATRICA, Issue 10 2004M Anatoliotaki Accelerated ventricular rhythm (AVR) was observed in two newborn infants. In the first case, arrhythmia was noted during the foetal period. Both neonates were asymptomatic and had no evidence of cardiac disease. The arrhythmia eventually disappeared when the infants were 4 mo and 24 d old, respectively. AVR in the neonatal period is reviewed in this report and recent information regarding appropriate diagnostic evaluation, differentiation from ventricular tachycardia and treatment is outlined. Conclusion: Accelerated ventricular rhythm is a benign and self-limited arrhythmia in the neonatal period. However, it is important to differentiate it from other serious rhythm disorders, mainly ventricular tachycardia, in order to avoid unnecessary and potentially harmful treatment and to relieve parental anxiety. [source] | ||||||||||||||||