986 resultados para pectic substances
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The aim of this work is to present some practical, postmortem biochemistry applications to illustrate the usefulness of this discipline and reassert the importance of carrying out biochemical investigations as an integral part of the autopsy process. Five case reports are presented pertaining to diabetic ketoacidosis in an adult who was not known to suffer from diabetes and in presence of multiple psychotropic substances; fatal flecainide intoxication in a poor metabolizer also presenting an impaired renal function; diabetic ketoacidosis showing severe postmortem changes; primary aldosteronism presented with intracranial hemorrhage and hypothermia showing severe postmortem changes. The cases herein presented can be considered representative examples of the importance of postmortem biochemistry investigations, which may provide significant information useful in determining the cause of death in routine forensic casework or contribute to understanding the pathophysiological mechanisms involved in the death process.
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The lungs of small premature babies are at a developmental stage of finalizing their airway tree by a process called branching morphogenesis, and of creating terminal gas exchange units by a mechanism called septation. If the branching process is disturbed, the lung has a propensity to be hypoplastic. If septation is impaired, the terminal gas exchange units, the alveoli, tend to be enlarged and reduced in number, an entity known as bronchopulmonary dysplasia. Here, we review current knowledge of key molecules influencing branching and septation. In particular, we discuss the molecular similarities and dissimilarities between the two processes of airspace enlargement. Understanding of the molecular mechanisms regulating branching and septation may provide perinatologists with targets for improving lung growth and maturation.
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El consum de drogues no institucionalitzades té una important dimensió epidemiològica. En l'actualitat augmenta el consum de cocaïna i de cànnabis i s'estabilitza o disminueix el de opiacis. En la majoria dels països hi ha una relació entre la drogoaddicció i el delicte. Objectius: 1) Obtenir dades sociodemogràfiques en una població detinguda en els jutjats de guàrdia que passen a disposició judicial; 2) Obtenir dades sanitàries referents a infecció per VIH, VHC I VHB; 3) Obtenir dades de consums de cocaïna, haxis, heroïna, benzodiazepines i drogues de síntesis; 4) Conèixer la correlació o concordança clínico-analítica i, 5) Valorar la relació de l'addicció a drogues amb la delictologia. Subjectes i Mètodes: Estudi realitzat en una població de 151 subjectes consumidors de drogues il·legals detinguts a disposició judicial al Jutjat de guàrdia de la ciutat de Barcelona. Temps de l'estudi: 1,5 anys. Mètodes: Administració d'un qüestionari amb dades sociodemogràfiques, sanitàries i de consums de tòxics. Obtenció d'una mostra d'orina que es va analitzar per immunoassaig en l'analitzador AsXym (*Abbot). Els resultats es van interpretar com positius o negatius segons el punt de tall establert per al mètode. Resultats: El perfil de la mostra és un home solter, edat mitjana de 31.4 anys, amb estudis primaris i sense professió qualificada. La droga il·legal més consumida és la cocaïna, 77,5%, seguida dels opiacis 62,9%, del cànnabis 60,3% i benzodiazepines 61.6% (auto-medicades 40,9%). La prevalença de HIV va ser del 16,7%, VHC 37,9% i VHB 19,1%. La via intravenosa és utilitzada pel 46% dels cocainòmans i pel 53.8% del heroinòmans. Un 45.5% tenen signes compatibles amb UDVP. Només un 14.2% presentava signes de deteriorament físic i un 23.1% una clara síndrome d’abstinència. Existeix un 74.3% de correlació o concordança clínico-analítica. El delicte més relacionat amb el consum de drogues va ser els delictes contra la propietat. Conclusions i Discusió: Es detecta un alt consum de cocaïna i disminució de l'heroïna. El consum de cànnabis i benzodiazepines és elevat. Els delictes contra la propietat estan associats al consum de drogues il·legals. Propostes: L'estudi té aplicabilitat en medicina forense. El screening rutinari d'orina en població detinguda és una mesura d'utilitat. Permet obtenir dades objectives quan se sol·liciten informes de drogoaddicció als perits. Els detinguts poden beneficiar-se de circumstàncies modificadores de la responsabilitat criminal en cas de ser consumidors de tòxics, d’acord amb la legislació actual. Els lletrats i l'autoritat judicial tindran una prova objectiva en les seves actuacions per poder resoldre amb més coneixement els procediments on es troben implicats els consumidors de drogues d'abús.
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The behavioural response of Triatoma pseudomaculata to chemical substances present in their faeces or cuticle (footprints) was analyzed. Groups of larvae were simultaneously exposed to a clean filter paper and to another paper impregnated with a chemical stimulus in a circular arena. In these choice experiments, the insects aggregated significantly around papers impregnated with dry faeces. In addition, the bugs also showed a significant aggregation response to papers impregnated with compounds derived from their cuticle that were deposited by contact on the substrate. These results indicate that chemical compounds that affect the behaviour of T. pseudomaculata are present in the faeces and in the cuticle of this species. Results are discussed in relation to chemical communication in the Triatominae, as well as to the potential use of these substances in traps or sensors for the detection of this species.
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PURPOSE OF REVIEW: This review discusses publications highlighting current research on toxic, chemotherapy-induced peripheral neuropathies (CIPNs), and drug-induced peripheral neuropathies (DIPNs). RECENT FINDINGS: The emphasis in clinical studies is on the early detection and grading of peripheral neuropathies, whereas recent studies in animal models have given insights into molecular mechanisms, with the discovery of novel neuronal, axonal, and Schwann cell targets. Some substances trigger inflammatory changes in the peripheral nerves. Pharmacogenetic techniques are underway to identify genes that may help to predict individuals at higher risk of developing DIPNs. Several papers have been published on chemoprotectants; however, to date, this approach has not been shown effective in clinical trials. SUMMARY: Both length and nonlength-dependent neuropathies are encountered, including small-fiber involvement. The introduction of new diagnostic techniques, such as excitability studies, skin laser Doppler flowmetry, and pharmacogenetics, holds promise for early detection and to elucidate underlying mechanisms. New approaches to improve functions and quality of life in CIPN patients are discussed. Apart from developing less neurotoxic anticancer therapies, there is still hope to identify chemoprotective agents (erythropoietin and substances involved in the endocannabinoid system are promising) able to prevent or correct painful CIPNs.
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OBJECTIVES: Previous literature suggests that early psychosis (EP) patients with a history of offending behavior (HOB) have specific clinical needs. The aims of this study were to assess: (1) the prevalence of HOB in a representative sample of EP; (2) the premorbid and baseline characteristics of patients with HOB, and (3) the potential differences in short-term outcome of such patients when compared to patients without HOB. METHODS: The Early Psychosis Prevention and Intervention Centre (EPPIC) admitted 786 EP patients between 1998 and 2000. Data were collected from patients' files using a standardized questionnaire. Data of 647 patients could be analyzed. RESULTS: HOB patients (29% of the sample) were more likely to be male with lower level of premorbid functioning and education, have used illicit substances and have attempted suicide. They presented with a more complex clinical picture and had poorer 18-month outcome. Most importantly, they had a significantly longer duration of untreated psychosis. CONCLUSIONS: On the basis of the high prevalence and specific features of EP patients with HOB, our study confirms a need for additional research in this domain and for the development of specific treatment strategies. Most importantly, it suggests a need for the promotion of early detection strategies among the populations of young offenders, considering that some of them may be going through the early phases of a psychotic disorder and that reduction of treatment delay and provision of well adapted interventions may have a significant impact at numerous levels in such patients.
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To investigate the role of the coreceptor CD8 and lipid rafts in cytotoxic T lymphocyte (CTL) activation, we used soluble mono-and multimeric H-2Kd-peptide complexes and cloned S14 CTL specific for a photoreactive derivative of the Plasmodium berghei circumsporozoite (PbCS) peptide 252-260 [PbCS(ABA)]. We report that activation of CTL in suspension requires multimeric Kd-PbCS(ABA) complexes co-engaging TCR and CD8. Using TCR ligand photo-cross-linking, we find that monomeric Kd-PbCS(ABA) complexes promote association of TCR/CD3 with CD8/p56lck. Dimerization of these adducts results in activation of p56lck in lipid rafts, where phosphatases are excluded. Additional cross-linking further increases p56lck kinase activity, induces translocation of TCR/CD3 and other signaling molecules to lipid rafts and intracellular calcium mobilization. These events are prevented by blocking Src kinases or CD8 binding to TCR-associated Kd molecules, indicating that CTL activation is initiated by cross-linking of CD8-associated p56lck. They are also inhibited by methyl-beta-cyclodextrin, which disrupts rafts and by dipalmitoyl phosphatidylethanolamine, which interferes with TCR signaling. Because efficient association of CD8 and p56lck takes place in rafts, both reagents, though in different ways, impair coupling of p56lck to TCR, thereby inhibiting the initial and essential activation of p56lck induced by cross-linking of engaged TCR.
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AIM: Antidoping procedures are expected to greatly benefit from untargeted metabolomic approaches through the discovery of new biomarkers of prohibited substances abuse. RESULTS: Endogenous steroid metabolites were monitored in urine samples from a controlled elimination study of testosterone undecanoate after ingestion. A platform coupling ultra-high pressure LC with high-resolution quadrupole TOF MS was used and high between-subject metabolic variability was successfully handled using a multiblock data analysis strategy. Links between specific subsets of metabolites and influential genetic polymorphisms of the UGT2B17 enzyme were highlighted. CONCLUSION: This exploratory metabolomic strategy constitutes a first step toward a better understanding of the underlying patterns driving the high interindividual variability of steroid metabolism. Promising biomarkers were selected for further targeted study.
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Treatment-resistant hypertension is still common despite the availability of several types of antihypertensive agents acting by different mechanisms. The existence of refractory hypertension should lead to rule out "white-coat hypertension", poor adherence to prescribed drugs as well as classical causes of secondary hypertension such as renal artery stenosis, primary aldosteronism, pheochromocytoma and renal disease. It is also important to consider the possible existence of obstructive sleep apnea or the regular intake of vasopressive drugs or substances.
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The increasing number of bomb attacks involving improvised explosive devices, as well as the nature of the explosives, give rise to concern among safety and law enforcement agencies. The substances used in explosive charges are often everyday products diverted from their primary licit applications. Thus, reducing or limiting their accessibility for prevention purposes is difficult. Ammonium nitrate, employed in agriculture as a fertiliser, is used worldwide in small and large homemade bombs. Black powder, dedicated to hunting and shooting sports, is used illegally as a filling in pipe bombs causing extensive damage. If the main developments of instrumental techniques in explosive analysis have been constantly pushing the limits of detection, their actual contribution to the investigation of explosives in terms of source discrimination is limited. Forensic science has seen the emergence of a new technology, isotope ratio mass spectrometry (IRMS), that shows promising results. Its very first application in forensic science dates back to 1979. Liu et al. analysed cannabis plants coming from different countries [Liu et al. 1979]. This preliminary study highlighted its potential to discriminate specimens coming from different sources. Thirty years later, the keen interest in this new technology has given rise to a flourishing number of publications in forensic science. The countless applications of IRMS to a wide range of materials and substances attest to its success and suggest that the technique is ready to be used in forensic science. However, many studies are characterised by a lack of methodology and fundamental data. They have been undertaken in a top-down approach, applying this technique in an exploratory manner on a restricted sampling. This manner of procedure often does not allow the researcher to answer a number of questions, such as: do the specimens come from the same source, what do we mean by source or what is the inherent variability of a substance? The production of positive results has prevailed at the expense of forensic fundamentals. This research focused on the evaluation of the contribution of the information provided by isotopic analysis to the investigation of explosives. More specifically, this evaluation was based on a sampling of black powders and ammonium nitrate fertilisers coming from known sources. Not only has the methodology developed in this work enabled us to highlight crucial elements inherent to the methods themselves, but also to evaluate both the longitudinal and transversal variabilities of the information. First, the study of the variability of the profile over time was undertaken. Secondly, the variability of black powders and ammonium nitrate fertilisers within the same source and between different sources was evaluated. The contribution of this information to the investigation of explosives was then evaluated and discussed. --------------------------------------------------------------------------------------------------- Le nombre croissant d'attentats à la bombe impliquant des engins explosifs artisanaux, ainsi que la nature des charges explosives, constituent une préoccupation majeure pour les autorités d'application de la loi et les organismes de sécurité. Les substances utilisées dans les charges explosives sont souvent des produits du quotidien, détournés de leurs applications licites. Par conséquent, réduire ou limiter l'accessibilité de ces produits dans un but de prévention est difficile. Le nitrate d'ammonium, employé dans l'agriculture comme engrais, est utilisé dans des petits et grands engins explosifs artisanaux. La poudre noire, initialement dédiée à la chasse et au tir sportif, est fréquemment utilisée comme charge explosive dans les pipe bombs, qui causent des dommages importants. Si les développements des techniques d'analyse des explosifs n'ont cessé de repousser les limites de détection, leur contribution réelle à l'investigation des explosifs est limitée en termes de discrimination de sources. Une nouvelle technologie qui donne des résultats prometteurs a fait son apparition en science forensique: la spectrométrie de masse à rapport isotopique (IRMS). Sa première application en science forensique remonte à 1979. Liu et al. ont analysé des plants de cannabis provenant de différents pays [Liu et al. 1979]. Cette étude préliminaire, basée sur quelques analyses, a mis en évidence le potentiel de l'IRMS à discriminer des spécimens provenant de sources différentes. Trente ans plus tard, l'intérêt marqué pour cette nouvelle technologie en science forensique se traduit par un nombre florissant de publications. Les innombrables applications de l'IRMS à une large gamme de matériaux et de substances attestent de son succès et suggèrent que la technique est prête à être utilisée en science forensique. Cependant, de nombreuses études sont caractérisées par un manque de méthodologie et de données fondamentales. Elles ont été menées sans définir les hypothèses de recherche et en appliquant cette technique de façon exploratoire sur un échantillonnage restreint. Cette manière de procéder ne permet souvent pas au chercheur de répondre à un certain nombre de questions, tels que: est-ce que deux spécimens proviennent de la même source, qu'entend-on par source ou encore quelle est l'intravariabilité d'une substance? La production de résultats positifs a prévalu au détriment des fondamentaux de science forensique. Cette recherche s'est attachée à évaluer la contribution réelle de l'information isotopique dans les investigations en matière d'explosifs. Plus particulièrement, cette évaluation s'est basée sur un échantillonnage constitué de poudres noires et d'engrais à base de nitrate d'ammonium provenant de sources connues. La méthodologie développée dans ce travail a permis non seulement de mettre en évidence des éléments cruciaux relatifs à la méthode d'analyse elle-même, mais également d'évaluer la variabilité de l'information isotopique d'un point de vue longitudinal et transversal. Dans un premier temps, l'évolution du profil en fonction du temps a été étudiée. Dans un second temps, la variabilité du profil des poudres noires et des engrais à base de nitrate d'ammonium au sein d'une même source et entre différentes sources a été évaluée. La contribution de cette information dans le cadre des investigations d'explosifs a ensuite été discutée et évaluée.
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OBJECTIVES: Skin notations are used as a hazard identification tool to flag chemicals associated with a potential risk related to transdermal penetration. The transparency and rigorousness of the skin notation assignment process have recently been questioned. We compared different approaches proposed as criteria for these notations as a starting point for improving and systematizing current practice. METHODS: In this study, skin notations, dermal acute lethal dose 50 in mammals (LD(50)s) and two dermal risk indices derived from previously published work were compared using the lists of Swiss maximum allowable concentrations (MACs) and threshold limit values (TLVs) from the American Conference of Governmental Industrial Hygienists (ACGIH). The indices were both based on quantitative structure-activity relationship (QSAR) estimation of transdermal fluxes. One index compared the cumulative dose received through skin given specific exposure surface and duration to that received through lungs following inhalation 8 h at the MAC or TLV. The other index estimated the blood level increase caused by adding skin exposure to the inhalation route at kinetic steady state. Dermal-to-other route ratios of LD(50) were calculated as secondary indices of dermal penetrability. RESULTS: The working data set included 364 substances. Depending on the subdataset, agreement between the Swiss and ACGIH skin notations varied between 82 and 87%. Chemicals with a skin notation were more likely to have higher dermal risk indices and lower dermal LD(50) than chemicals without a notation (probabilities between 60 and 70%). The risk indices, based on cumulative dose and kinetic steady state, respectively, appeared proportional up to a constant independent of chemical-specific properties. They agreed well with dermal LD(50)s (Spearman correlation coefficients -0.42 to -0.43). Dermal-to-other routes LD(50) ratios were moderately associated with QSAR-based transdermal fluxes (Spearman correlation coefficients -0.2 to -0.3). CONCLUSIONS: The plausible but variable relationship between current skin notations and the different approaches tested confirm the need to improve current skin notations. QSAR-based risk indices and dermal toxicity data might be successfully integrated in a systematic alternative to current skin notations for detecting chemicals associated with potential dermal risk in the workplace. [Authors]
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Results of the National Health and Lifestyle Surveys: SLaN [Survey of Lifestyle, Attitudes and Nutrition] and HBSC [Health Behaviour in School-Aged Children] Two baseline surveys of health related behaviours among adults and schoolgoing young people were carried out across the Republic of Ireland in 1998 and again in 2002. The main aims of these surveys are to: - Produce reliable data of a representative cross-section of the Irish population in order to inform the Department of Health and Children's policy and programme planning. - Maintain a survey protocol which will enable lifestyle factors to be remeasured so that trends can be identified and changes monitored to assist national and regional setting of priorities in health promotion activities. In keeping with the health and lifestyle surveillance system of many European countries a number of related factors were measured in both surveys. These include general health, smoking, use of alcohol and other substances, food and nutrition, exercise and accidents. This work was commissioned by the Health Promotion Unit, Department of Health and Children and carried out at the Centre for Health Promotion Studies, National University of Ireland, Galway.This resource was contributed by The National Documentation Centre on Drug Use.
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Two baseline surveys of health related behaviours among adults and school-going young people were carried out across the Republic of Ireland in 1998 and again in 2002. The main aims of these surveys are to: - Produce reliable data of a nationally representative cross-section of the Irish population in order to inform the Department of health and Children's policy and programme planning. - Maintain a survey protocol which will enable lifestyle factors to be re-measured so that trends can be identified and changes monitored to assist national and regional setting of priorities in health promotion activities. This report focuses on these two cross-sectional studies, SLaN (Survey of Lifestyles, Attitudes and Nutrition) adults aged 18+ years and HBSC (health Behaviour in School-aged Children) school-going children aged 10-17 years. In keeping with the health and lifestyle surveillance system of many European countries a number of related factors were measured in both surveys. These include general health, smoking, use of alcohol and other substances, food and nutrition, exercise and accidents. This report presents the findings for the same topics at a regional level with some demographic analysis. It must be noted that the aim of the survey was to establish patterns in health and lifestyle at a national level. The significance therefore of findings at the regional level is to identify potential variations that may merit further investigation. This work was commissioned by the health Promotion Unit, Department of health and Children and carried out at the Centre for health Promotion Studies, national University of Ireland, Galway, and at the Department of Public health Medicine and Epidemiology, Woodview House, Belfield, national University of Ireland, Dublin.This resource was contributed by The National Documentation Centre on Drug Use.
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The inability to deal with substance misuse is a universal human problem. No country has discovered a failsafe way of tackling it. In Ireland there is an annual public outcry about an ever-deepening drinking culture but once the outcry is over the problem subsides below consciousness. Strategies are created and launched and quickly forgotten. Everybody is aware of the problem in their own family or neighbourhood and everybody has their own opinion on causes and remedies. Why then does nothing seem to work? After demonstrating the shortcomings of previous models of addiction, Jack Houlahan identifies a pattern that all human use of substances has in common. In A Ghost in Daylight, the general reader will find many popular stereotypes re-examined in a way that will illuminate their own experience; the specialist addiction worker or researcher will find reason to challenge first principles; a new approach to counselling and advice work is suggested; the policy-maker will find a firm foundation for what will be the first attempt at an integrated policy for dealing with the range of issues we group under the title 'substance misuse'.This resource was contributed by The National Documentation Centre on Drug Use.