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81.
Hymenoptera venom allergy is a potentially life‐threatening allergic reaction following a honeybee, vespid, or ant sting. Systemic‐allergic sting reactions have been reported in up to 7.5% of adults and up to 3.4% of children. They can be mild and restricted to the skin or moderate to severe with a risk of life‐threatening anaphylaxis. Patients should carry an emergency kit containing an adrenaline autoinjector, H1‐antihistamines, and corticosteroids depending on the severity of their previous sting reaction(s). The only treatment to prevent further systemic sting reactions is venom immunotherapy. This guideline has been prepared by the European Academy of Allergy and Clinical Immunology's (EAACI) Taskforce on Venom Immunotherapy as part of the EAACI Guidelines on Allergen Immunotherapy initiative. The guideline aims to provide evidence‐based recommendations for the use of venom immunotherapy, has been informed by a formal systematic review and meta‐analysis and produced using the Appraisal of Guidelines for Research and Evaluation (AGREE II) approach. The process included representation from a range of stakeholders. Venom immunotherapy is indicated in venom‐allergic children and adults to prevent further moderate‐to‐severe systemic sting reactions. Venom immunotherapy is also recommended in adults with only generalized skin reactions as it results in significant improvements in quality of life compared to carrying an adrenaline autoinjector. This guideline aims to give practical advice on performing venom immunotherapy. Key sections cover general considerations before initiating venom immunotherapy, evidence‐based clinical recommendations, risk factors for adverse events and for relapse of systemic sting reaction, and a summary of gaps in the evidence.  相似文献   
82.
Recently, multichannel intraluminal impedance (MII) monitoring was added to the repertoire of tests to evaluate the (patho)physiology of gastroesophageal reflux (GER) in children. Its advantage above the sole monitoring of the esophageal pH lies in the ability of the detection of both acid and nonacid GER and to discern between liquid and gas GER. Currently, combined 24 h pH‐MII monitoring is recommended for evaluation of gastro‐esophageal reflux disease (GERD) and its relation to symptoms in infants and children, despite the lack of reference values in these age groups. There is new evidence in the current issue of this Journal supporting the role of pH‐MII monitoring for the evaluation of children presenting with gastrointestinal symptoms suggestive of GERD and the prediction of the presence of reflux esophagitis. However, several issues should be taken into account when performing pH‐MII clinically.  相似文献   
83.
This review focuses on the plasticity of the regulation of a particular neuroendocrine transducer cell, the melanotrope cell in the pituitary pars intermedia of the amphibian Xenopus laevis. This cell type is a suitable model to study the relationship between various external regulatory inputs and the secretion of an adaptive endocrine message, in this case the release of α-melanophore-stimulating hormone, which activates skin melanophores to darken when the animal is placed on a dark background. Information about the environmental conditions is processed by various brain centres, in the hypothalamus and elsewhere, that eventually control the activity of the melanotrope cell regarding hormone production and secretion. The review discusses the roles of these hypothalamic and extrahypothalamic nuclei, their neurochemical messengers acting on the melanotrope, and the external stimuli they mediate to control melanotrope cell functioning.  相似文献   
84.
Challenges for the effective molecular imprinting of proteins   总被引:1,自引:0,他引:1  
Molecular imprinting is a technique that is used to create artificial receptors by the formation of a polymer network around a template molecule. This technique has proven to be particularly effective for molecules with low molecular weight (<1500 Da), and during the past five years the number of research articles on the imprinting of larger (bio)templates is increasing considerably. However, expanding the methodology toward imprinted materials for selective recognition of proteins, DNA, viruses and bacteria appears to be extremely challenging. This paper presents a critical analysis of data presented by several authors and our own experiments, showing that the molecular imprinting of proteins still faces some fundamental challenges. The main topics of concern are proper monomer selection, washing method/template removal, quantification of the rebinding and reproducibility. Use of charged monomers can lead to strong electrostatic interactions between monomers and template but also to undesired high aspecific binding. Up till now, it has not been convincingly shown that electrostatic interactions lead to better imprinting results. The combination of a detergent (SDS) and AcOH, commonly used for template removal, can lead to experimental artifacts, and should ideally be avoided. In many cases template rebinding is unreliably quantified, results are not evaluated critically and lack statistical analysis. Therefore, it can be argued that presently, in numerous publications the scientific evidence of molecular imprinting of proteins is not convincing.  相似文献   
85.
Introduction Several studies have paid attention to the relationship between psychiatric disorders and adolescent offending but few have distinguished different types of offenders, especially within the category of youngsters who have committed sex offences. Aim To test for relationships between psychiatric disorder and specific offence category among young male offenders. Method Nationwide data were extracted from Dutch Forensic Psychiatric Services (FPD) files for five groups of offenders, as defined by their index offence: 308 violent sex offenders; 134 non‐violent sex‐offenders; 270 sex offenders against children; 3148 violent offenders and 1620 offenders charged with any crime other than interpersonal body contact crimes. They were compared on individual characteristics and psychiatric diagnoses according to DSM‐IV criteria. Having a diagnosis of a paraphilia alone was exclusively associated with sex offending, therefore all such youths were excluded from further analyses. The OVERALS technique was used to explore possible relationships between offence, psychiatric diagnoses, sociodemographic and individual characteristics among the remaining young men for whom all pertinent data were available (n = 1894). Results Sex offenders constituted a distinct group of juvenile delinquents. Developmental disorders were more common among non‐violent sex offenders and child molesters. Violent offences were more typical of delinquents from immigrant backgrounds. Conclusion Group differences in types of psychiatric diagnoses may reflect differences in aetiological factors for the various types of sexual and other delinquent behaviour, and this would be worthy of further study. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
86.
Growth factors, such as ciliary neurotrophic factor (CNTF), have been implicated in neuronal survival and proliferation. About 2% of the human population is homozygous for a polymorphism that induces truncated and biologically inactive CNTF but does not obviously change the phenotype. In a population of patients with hereditary neuropathy, a higher rate of the CNTF null mutation would indicate greater susceptibility for clinically significant disease, and a recent report attributes early onset and rapid deterioration in a case of familial ALS (FALS) to this mutation. We have, therefore, genotyped the CNTF polymorphism in a large group of patients with CMT 1a, HNPP, sporadic ALS, in one pedigree with FALS, and controls. All groups exhibited a similar distribution of the polymorphism. We conclude that absence of CNTF does not increase susceptibility for these disorders and confirm that it does not affect onset and course of familial and sporadic ALS.  相似文献   
87.
88.

Background:

Bile duct obstruction is associated with hepatic accumulation of leukocytes and liver injury. The aim of this study was to evaluate the effect of simvastatin on cholestasis-induced liver inflammation and tissue damage.

Experimental approach:

C57BL/6 mice were treated with simvastatin (0.02 and 0.2 mg·kg−1) and vehicle before and after undergoing bile duct ligation (BDL) for 12 h. Leukocyte recruitment and microvascular perfusion in the liver were analysed using intravital fluorescence microscopy. CXC chemokines in the liver were determined by enzyme-linked immunosorbent assay. Liver damage was monitored by measuring serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Hepatic levels of myeloperoxidase (MPO) were also determined.

Key results:

Administration of 0.2 mg·kg−1 simvastatin decreased ALT and AST by 87% and 83%, respectively, in BDL mice. This dose of simvastatin reduced hepatic formation of CXC chemokines by 37–82% and restored sinusoidal perfusion in cholestatic animals. Moreover, BDL-induced leukocyte adhesion in sinusoids and postsinusoidal venules, as well as MPO levels in the liver, was significantly reduced by simvastatin. Notably, administration of 0.2 mg·kg−1 simvastatin 2 h after BDL induction also decreased cholestatic liver injury and inflammation.

Conclusions and implications:

These findings show that simvastatin protects against BDL-induced liver injury. The hepatoprotective effect of simvastatin is mediated, at least in part, by reduced formation of CXC chemokines and leukocyte recruitment. Thus, our novel data suggest that the use of statins may be an effective strategy to protect against the hepatic injury associated with obstructive jaundice.  相似文献   
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