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BACKGROUND: Results from several studies indicate that the magnitude of immediate symptoms of type I allergy caused by allergen-induced cross-linking of high-affinity Fc epsilon receptors on effector cells (mast cells and basophils) is not always associated with allergen-specific IgE levels. OBJECTIVE: To investigate the association of results from intradermal skin testing, basophil histamine release and allergen-specific IgE, IgG1-4, IgA and IgM antibody levels in a clinical study performed in birch pollen-allergic patients (n = 18). METHODS: rBet v 1-specific IgEs were measured by quantitative CAP measurements and by using purified Fc epsilon RI-derived alpha-chain to quantify IgE capable of binding to effector cells. Bet v 1-specific IgG subclasses, IgA and IgM levels were measured by ELISA, and basophil histamine release was determined in whole blood samples. Intradermal skin testing was performed with the end-point titration method. RESULTS: Our study demonstrates on the molecular level that the concentrations of allergen-specific IgE antibodies capable of binding to Fc epsilon RI and biological sensitivities are not necessarily associated. A moderate association was found between cutaneous and basophil sensitivity. CONCLUSION: Our results highlight the quantitative discrepancies and limitations of the present diagnostic tools in allergy, even when using a single allergenic molecule. The quantity of allergen-specific serum IgE is only one component of far more complex cellular systems (i.e. basophil-based tests, skin tests) used as indirect diagnostic tests for IgE-mediated allergic sensitivity.  相似文献   
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Pyroglutamyl, proline-rich oligopeptides, classically referred to as bradykinin-potentiating peptides (BPPs) are found in Bothrops jararaca venom, and are naturally occurring inhibitors of the somatic angiotensin-converting enzyme (ACE). The chemical and pharmacological properties of these peptides were essential for the development of captopril, the first active site directed inhibitor of ACE, currently used to treat human hypertension. ACE is a complex ectoenzyme of the vascular endothelium, possessing two catalytic sites, performing diverse specific roles. Recent advances concerning novel features of BPPs revealed that they might still contribute to a better understanding of the cardiovascular physiology and pathology. The molecular biology of the BPPs revealed that they are part of two distinct C-type natriuretic peptide precursors found in the venom gland and the brain of B. jararaca, each containing seven BPPs. In situ hybridization studies detected the presence of the corresponding mRNA precursor in snake brain regions correlated with neuroendocrine functions, such as the ventro-medial hypothalamus, the paraventricular nuclei, the paraventricular organ, and the subcommissural organ. In this article we discuss the large variety of homologous BPPs in B. jararaca venom and brain, its significance, and whether the BPPs could represent novel endogenous neuropeptides.  相似文献   
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Abstract: We have designed and synthesized a new series of azapeptides which act as potential inhibitors of cathepsin B and/or cathepsin K. Their structures are based upon the inhibitory sites of natural cysteine protease inhibitors, cystatins. For the synthesized azapeptides, the equilibrium constants for dissociation of inhibitor–enzyme complex, Ki, were determined. Comparison of these values indicated that all of the azainhibitors act much stronger toward cathepsin B. Z‐Arg‐Leu‐His‐Agly‐Ile‐Val‐OMe ( 7 ) proved to be approximately 500 times more potent for cathepsin B than for cathepsin K. To be able to explain the obtained experimental values we used the molecular dynamics procedures to analyze the interactions between cathepsin B and compound 7 . We also determined the structure of the most potent and selective cathepsin B azainhibitor by means of NMR studies and theoretical calculations. In this report, we describe SAR studies of azapeptide inhibitors indicating the influence of the conformational flexibility of the examined compounds on inhibition of cathepsins B and K.  相似文献   
15.
Objective To investigate the best way to control the blood sugar level during the perioperation of bone fracture patients with type 2 diabetes(T2DM).Methods Bone fracture patients with T2DM were randomly divided into three groups:continuous subcutaneous insulin infusion group(insulin aspart,group CSII,n=20),glargine treatment group(insulin aspart+insulin glargine,group GA,n=20),and NPH treatment(insulin aspart+rh-insulin,group NA,n=20).The levels of fasting plasma glucose(FPG)and the 2 hours postprandial glucose(2h PG),blood glucose fluctuation(BGF),insulin dosage(ID),good effective time(GET),incidence of hypoglycemia,dawn phenomenon and infection,average time of stitches removal(ATSR),average hospitalized length(AHL)of three groups were compared.Results FPG and 2hPG,ID in group CSII[(6.32±1.18)mmol/L,(7.72±1.53)mmol/L,(35.40±1.60)IU]and group GA [(6.25±0.88)mmol/L,(7.32±1.17)mmol/L,(36.20±0.80)IU]were significantly lower than those of group NA [(7.44±1.36)mmol/L,(8.52±0.76)mmol/L,(40.50±2.40)IU,all P<0.05],simulaneously,BGF,GET incidence of complications,ATSR,AHL of group CSII and GA were significantly lower than those of group NA(all P<0.05).There were not significant difference between group CSII and group GA.Compared with group CSII,group GA had less costs in-hospital and better practicability.Conclusion Both CSII and insulin glargine combined with insulin aspart can effectively,safely,rapidly and stablely control hyperglycemia.and might be the first choice to control blood sugar for bone fracture patients with T2DM in perioperation.  相似文献   
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The greatest benefit of immunosuppression minimization for children may lie in improving patient morbidity, by the elimination of the inherent side effects of steroid and calcineurin inhibitors (CNI). The newer generation of powerful induction and maintenance immunosuppressants offers an option for selected immunosuppression minimization strategies, some of which have been shown to also reduce graft morbidity. Steroid minimization and avoidance in single-center uncontrolled trials have shown early promise and the availability of data from an ongoing randomized, prospective, controlled trial of steroid avoidance in children will provide necessary data to support a practice change for steroid elimination in children. Calcineurin inhibitor minimization and addition of mycophenolate mofetil (MMF) or sirolimus have shown variable improvements in renal function, though suboptimal efficacy and safety with the currently proposed regimes have limited their application. Randomized, prospective studies of steroid and calcineurin inhibitor minimization and/or avoidance are warranted to clearly confirm the short and long-term safety and efficacy of alternative immunosuppression combinations. Linked pharmacokinetic and mechanistic studies within these trials will allow for optimizing drug dosing and monitoring. This article reviews published experience to date with steroid and calcineurin minimization in pediatric renal transplantation and discusses the risks and benefits of these approaches.  相似文献   
17.
比较对新诊断2型糖尿病患者应用瑞格列奈(11例)和迪沙片(10例)治疗4周后空腹血糖(FPG)、餐后2h血糖(2hPG)、晨3点血糖(3aPG),空腹胰岛素(FIns)、餐后2h胰岛素(2hIns),糖化白蛋白的值。结果显示,与迪沙片组相比,瑞格列奈组治疗后空腹血糖、餐后2h血糖的下降幅度更为明显,但低血糖的发生次数反而减少。  相似文献   
18.
The recent global resurgence of mumps has drawn attention to the continued need for robust mumps immunization programs. Unfortunately, some vaccines derived from inadequately attenuated vaccine strains of mumps virus have caused meningitis in vaccinees, leading to withdrawal of certain vaccine strains from the market, public resistance to vaccination, or in some cases, cessation of national mumps vaccination programs. The most widely implicated mumps vaccine in cases of postvaccination meningitis is derived from the Urabe AM9 strain, which remains in use in some countries. The Urabe AM9 vaccine virus has been shown to exhibit a considerable degree of nucleotide and amino acid heterogeneity. Some studies have specifically implicated variants containing a lysine residue at amino acid position 335 in the hemagglutinin-neuraminidase (HN) protein with neurotoxicity, whereas a glutamic acid residue at this position was associated with attenuation. To test this hypothesis we generated two modified Urabe AM9 cDNA clones coding either for a lysine or a glutamic acid at position 335 in the HN gene. The two viruses were rescued by reverse genetics and characterized in vitro and in vivo. Both viruses exhibited similar growth kinetics in neuronal and non-neuronal cell lines and were of similar neurotoxicity when tested in rats, suggesting that amino acid 335 is not a crucial determinant of Urabe AM9 growth or neurovirulence.  相似文献   
19.
Abstract: Stellate ganglion block is commonly used to treat the sympathetically maintained pain which may occur in one‐third of patients with complex regional pain syndrome type 1. A complication that followed a single block and presented a diagnostic dilemma for the ophthalmologist is reported.  相似文献   
20.
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