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1.
Allergy ; 77(10): 3028-3040, 2022 10.
Article in English | MEDLINE | ID: mdl-35485989

ABSTRACT

BACKGROUND: Diagnosis of food allergies is challenging, as combining information from specific IgE (sIgE)-sensitization pattern and skin prick tests (SPTs) with clinical history is necessary for a personalized management of allergic patients. The aim of this study was to compare two molecular tests, the ImmunoCAP ISAC (ISAC) and the Allergy Explorer, version 2 (ALEX2 ) in the context of pollen food syndrome (PFS) diagnosis in a real-life scenario, to assess the benefit of multiplex testing in PFS patients. METHODS: Diagnosis of food allergy was performed in 53 patients. Allergen-sIgE concentrations were measured with ISAC and ALEX2 . Results for sIgE were statistically compared with each other, with SPT results and with clinical presentation of the patients. RESULTS: Using ISAC as reference test for sIgE measurements, the average sensitivity of ALEX2 for PR-10 allergens was 83.2% and the average specificity 88.0%. If only low sIgE concentrations were included, the sensitivity was 60.8% and the specificity 91.1%. Apple and hazelnut sensitizations were confirmed in most patients by concordance of sIgE and SPT results. Significant correlations were shown between clinical symptoms and Mal d 1- and Gly m 4-sIgE levels measured by both tests and for Cor a 1-sIgE levels measured by ALEX2 . In eight patients, profilin related symptoms were supported by Hev b 8-sensitization. CONCLUSION: Multiplex testing is beneficial to understand patient-specific individual sensitization profiles and to providing personalized management recommendations. In the future, custom-designed test kits might enable reducing costs of multiplex testing for specific patient groups without compromising the diagnostic value.


Subject(s)
Food Hypersensitivity , Profilins , Allergens , Food Hypersensitivity/diagnosis , Humans , Immunoglobulin E , Pollen , Skin Tests/methods
2.
J Chem Inf Model ; 60(11): 5319-5330, 2020 11 23.
Article in English | MEDLINE | ID: mdl-32786697

ABSTRACT

Computational prediction of limiting activity coefficients is of great relevance for process design. For highly nonideal mixtures including molecules with directed interactions, methods that maintain the molecular character of the solvent are most promising. Computational expense and force-field deficiencies are the main limiting factors that prevent the use of high-throughput molecular dynamics (MD) simulations in a predictive setup. The combination of MD simulations and machine learning used in this work accounts for both issues. Comparison to published data including free-energy simulations, COSMO-RS and UNIFAC models, reveals competitive prediction accuracy.


Subject(s)
Machine Learning , Molecular Dynamics Simulation , Solvents , Thermodynamics
3.
J Phys Chem B ; 122(5): 1608-1626, 2018 02 08.
Article in English | MEDLINE | ID: mdl-29287148

ABSTRACT

Molecular dynamics simulations of native α-, ß-, and γ-cyclodextrin in aqueous solution have been conducted with the goal to investigate the performance of the CHARMM36 force field, the AMBER-compatible q4md-CD force field, and five variants of the GROMOS force field. The properties analyzed are structural parameters derived from X-ray diffraction and NMR experiments as well as hydrogen bonds and hydration patterns, including hydration free enthalpies. Recent revisions of the torsional-angle parameters for carbohydrate systems within the GROMOS family of force fields lead to a significant improvement of the agreement between simulated and experimental NMR data. Therefore, we recommend using the variant 53A6GLYC instead of 53A6 and 56A6CARBO_R or 2016H66 instead of 56A6CARBO to simulate cyclodextrins in solution. The CHARMM36 and q4md-CD force fields show a similar performance as the three recommended GROMOS parameter sets. A significant difference is the more flexible nature of the cyclodextrins modeled with the CHARMM36 and q4md-CD force fields compared to the three recommended GROMOS parameter sets.


Subject(s)
Cyclodextrins/chemistry , Molecular Dynamics Simulation , Thermodynamics , Molecular Structure , Reproducibility of Results , Solutions , Water/chemistry
4.
J Pediatr Endocrinol Metab ; 30(8): 815-821, 2017 Aug 28.
Article in English | MEDLINE | ID: mdl-28245190

ABSTRACT

BACKGROUND: Impaired glucose metabolism and cystic fibrosis (CF)-related diabetes (CFRD) are associated with insufficient weight gain and impaired lung function in children and adolescents with CF. We have asked whether imminent CFRD may be a cause of poor growth in children and adolescents. METHODS: A retrospective case control study including 32 patients with CF with or without diabetes was conducted. Sixteen pairs, matched according to age, gender and exocrine pancreatic insufficiency, were analysed. Standard deviation scores (SDS) of height, growth, weight, body mass index (BMI), forced vital capacity (FVC), forced expiratory volume in the first second (FEV1) and forced expiratory flow at 75% of expired FVC (FEF75) were recorded during a mean observation period of 13 years per patient. RESULTS: SDS of height and weight were reduced in CF patients with diabetes compared to those without, not only at the point of diagnosis (both p<0.05) but years before the evidence of diabetes. Afterwards there was a significant decline in height (p<0.001) and weight (p<0.01) SDS in CFRD patients and an increasing difference between the height and weight of CF patients with or without diabetes. In contrast, no significant reduction of BMI-SDS was observed in CFRD patients. All analysed lung function parameters showed a marked decline in CFRD patients starting 1 year prior to the diagnosis of diabetes. CONCLUSIONS: Deteriorating growth, reduced weight and impaired lung function are related to the development of CFRD and are obvious several years before the actual diagnosis of diabetes.


Subject(s)
Cystic Fibrosis/complications , Diabetes Mellitus/etiology , Growth Disorders/etiology , Lung/physiopathology , Adolescent , Case-Control Studies , Child , Cystic Fibrosis/physiopathology , Diabetes Mellitus/physiopathology , Female , Glucose Tolerance Test , Growth Disorders/physiopathology , Humans , Male , Respiratory Function Tests , Retrospective Studies , Weight Gain/physiology , Young Adult
5.
Heart Vessels ; 31(5): 783-94, 2016 May.
Article in English | MEDLINE | ID: mdl-26062773

ABSTRACT

The anti-platelet drug clopidogrel has been shown to modulate adhesion molecule and cytokine expression, both playing an important role in the pathogenesis of atherosclerosis. The aim of this study was to investigate the impact of clopidogrel on the development and progression of atherosclerosis. ApoE(-/-) mice fed an atherogenic diet (cholesterol: 1 %) for 6 months received a daily dose of clopidogrel (1 mg/kg) by i.p. injection. Anti-platelet treatment was started immediately in one experimental group, and in another group clopidogrel was started 2 month after beginning of the atherogenic diet. Blood was analysed at days 30, 60 and 120 to monitor the lipid profile. After 6 months the aortic arch and brachiocephalic artery were analysed by Sudan IV staining for plaque size and by morphometry for luminal occlusion. Serum levels of various adhesion molecules were investigated by ELISA and the cellular infiltrate was analysed by immunofluorescence. After daily treatment with 1 mg/kg clopidogrel mice showed a significant reduction of atherosclerotic lesions in the thoracic aorta and within cross sections of the aortic arch [plaque formation 55.2 % (clopidogrel/start) vs. 76.5 % (untreated control) n = 8, P < 0.05]. After treatment with clopidogrel P-/E-selectin levels and cytokine levels of MCP-1 and PDGFß were significantly reduced as compared to controls. The cellular infiltrate showed significantly reduced macrophage and T-cell infiltration in clopidogrel-treated animals. These results show that clopidogrel can effectively delay the development and progression of 'de-novo' atherosclerosis. However, once atherosclerotic lesions were already present, anti-platelet treatment alone did not result in reverse remodelling of these lesions.


Subject(s)
Aorta, Thoracic/drug effects , Aortic Diseases/prevention & control , Apolipoproteins E/deficiency , Atherosclerosis/prevention & control , Platelet Aggregation Inhibitors/pharmacology , Ticlopidine/analogs & derivatives , Animals , Aorta, Thoracic/immunology , Aorta, Thoracic/metabolism , Aorta, Thoracic/pathology , Aortic Diseases/blood , Aortic Diseases/genetics , Aortic Diseases/pathology , Apolipoproteins E/genetics , Atherosclerosis/blood , Atherosclerosis/genetics , Atherosclerosis/pathology , Biomarkers/blood , Chemokine CCL2/blood , Chemokine CCL2/genetics , Clopidogrel , Disease Models, Animal , Disease Progression , E-Selectin/blood , E-Selectin/genetics , Gene Expression Regulation , Genetic Predisposition to Disease , Lipids/blood , Lymphokines/blood , Lymphokines/genetics , Mice, Inbred C57BL , Mice, Knockout , P-Selectin/blood , P-Selectin/genetics , Phenotype , Plaque, Atherosclerotic , Platelet Aggregation/drug effects , Platelet-Derived Growth Factor/genetics , RNA, Messenger/genetics , RNA, Messenger/metabolism , Ticlopidine/pharmacology , Time Factors , Vascular Remodeling/drug effects
6.
J Atten Disord ; 18(2): 117-22, 2014 Feb.
Article in English | MEDLINE | ID: mdl-22713361

ABSTRACT

OBJECTIVE: ADHD is common among children with comorbidity of enuresis. Findings concerning prepulse inhibition (PPI) of startle reflexes are controversial. Although PPI is improved through desamino-arginine vasopressin (dDAVP) in enuresis, some patients also improve concomitant ADHD through dDAVP. This study aims to evaluate whether methylphenidate (MPH) also improves PPI in ADHD. METHOD: Nineteen ADHD patients were investigated in a prospective, double-blind, crossover study with MPH versus placebo. PPI was measured as a reduction of acoustic startle reflexes. Subgroups of gender, ADHD subtype, and baseline PPI were analyzed. RESULTS: Median baseline PPI of ADHD patients (51.7%) was below the value of age-matched normal controls (73%, p = .090). MPH showed no improvement in the whole group, or the subgroups gender or subtype. Reduced baseline PPI was significantly improved (22.5%-39.3%, p = .039). CONCLUSION: Heterogeneity of ADHD is confirmed with a wide range of baseline PPI. The improvement of reduced baseline PPI through MPH suggests impaired sensorimotor gating in this subgroup.


Subject(s)
Attention Deficit Disorder with Hyperactivity/drug therapy , Central Nervous System Stimulants/therapeutic use , Methylphenidate/therapeutic use , Reactive Inhibition , Reflex, Startle/drug effects , Acoustic Stimulation , Adolescent , Child , Cross-Over Studies , Deamino Arginine Vasopressin/therapeutic use , Double-Blind Method , Enuresis/drug therapy , Enuresis/etiology , Female , Humans , Male , Prospective Studies , Reflex, Startle/physiology , Treatment Outcome
7.
Antiviral Res ; 87(2): 162-78, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20471996

ABSTRACT

Caliciviridae are human or non-human pathogenic viruses with a high diversity. Some members of the Caliciviridae, i.e. human pathogenic norovirus or rabbit hemorrhagic disease virus (RHDV), are worldwide emerging pathogens. The norovirus is the major cause of viral gastroenteritis worldwide, accounting for about 85% of the outbreaks in Europe between 1995 and 2000. In the United States, 25 million cases of infection are reported each year. Since its emergence in 1984 as an agent of fatal hemorrhagic diseases in rabbits, RHDV has killed millions of rabbits and has been dispersed to all of the inhabitable continents. In view of their successful and apparently increasing emergence, the development of antiviral strategies to control infections due to these viral pathogens has now become an important issue in medicine and veterinary medicine. Antiviral strategies have to be based on an understanding of the epidemiology, transmission, clinical symptoms, viral replication and immunity to infection resulting from infection by these viruses. Here, we provide an overview of the mechanisms underlying calicivirus infection, focusing on the molecular aspects of replication in the host cell. Recent experimental data generated through an international collaboration on structural biology, virology and drug design within the European consortium VIZIER is also presented. Based on this analysis, we propose antiviral strategies that may significantly impact on the epidemiological characteristics of these highly successful viral pathogens.


Subject(s)
Antiviral Agents/therapeutic use , Caliciviridae Infections/epidemiology , Caliciviridae Infections/veterinary , Caliciviridae/drug effects , Disease Outbreaks , Animals , Antiviral Agents/pharmacology , Biomedical Research/organization & administration , Biomedical Research/trends , Caliciviridae Infections/drug therapy , Drug Design , Enzymes/chemistry , Enzymes/genetics , Enzymes/metabolism , Europe/epidemiology , European Union , Humans , United States/epidemiology , Viral Nonstructural Proteins/chemistry , Viral Nonstructural Proteins/genetics , Viral Nonstructural Proteins/metabolism , Virus Replication/drug effects
8.
J Virol ; 82(16): 8085-93, 2008 Aug.
Article in English | MEDLINE | ID: mdl-18550673

ABSTRACT

Sapovirus is a positive-stranded RNA virus with a translational strategy based on processing of a polyprotein precursor by a chymotrypsin-like protease. So far, the molecular mechanisms regulating cleavage specificity of the viral protease are poorly understood. In this study, the catalytic activities and substrate specificities of the predicted forms of the viral protease, the 3C-like protease (NS6) and the 3CD-like protease-polymerase (NS6-7), were examined in vitro. The purified NS6 and NS6-7 were able to cleave synthetic peptides (15 to 17 residues) displaying the cleavage sites of the sapovirus polyprotein, both NS6 and NS6-7 proteins being active forms of the viral protease. High-performance liquid chromatography and subsequent mass spectrometry analysis of digested products showed a specific trans cleavage of peptides bearing Gln-Gly, Gln-Ala, Glu-Gly, Glu-Pro, or Glu-Lys at the scissile bond. In contrast, peptides bearing Glu-Ala or Gln-Asp at the scissile bond (NS4-NS5 and NS5-NS6, or NS6-NS7 junctions, respectively) were resistant to trans cleavage by NS6 or NS6-7 proteins, whereas cis cleavage of the Glu-Ala scissile bond of the NS5-NS6 junction was evidenced. Interestingly, the presence of a Phe at position P4 overruled the resistance to trans cleavage of the Glu-Ala junction (NS5-NS6), whereas substitutions at the P1 and P2' positions altered the cleavage efficiency. The differential cleavage observed is supported by a model of the substrate-binding site of the sapovirus protease, indicating that the P4, P1, and P2' positions in the substrate modulate the cleavage specificity and efficiency of the sapovirus chymotrypsin-like protease.


Subject(s)
Chymases/chemistry , Sapovirus/chemistry , Viral Nonstructural Proteins/chemistry , Binding Sites , Catalytic Domain , Chromatography, High Pressure Liquid/methods , Chymases/metabolism , Mass Spectrometry/methods , Models, Genetic , Models, Molecular , Mutation , Open Reading Frames , Peptides/chemistry , Recombinant Proteins/chemistry , Sapovirus/enzymology , Substrate Specificity
9.
J Gen Virol ; 88(Pt 7): 2013-2018, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17554035

ABSTRACT

Protein translation in noroviruses requires translational processing of a polyprotein precursor by the viral protease. So far, the molecular mechanisms of catalytic cleavage by the viral protease are poorly understood. In this study, the catalytic activities and substrate specificities of the viral protease were examined in vitro by using synthetic peptides (11-15 residues) corresponding to the cleavage sites of the norovirus polyprotein. Both predicted forms of the viral protease, the 3C-like protease (3C(pro)) and the 3CD-like protease polymerase protein (3CD(propol)), displayed a specific trans cleavage activity of peptides bearing Gln-Gly at the scissile bond. In contrast, peptides bearing Glu-Gly at the scissile bond (p20/VPg and 3C(pro)/3D(pol) junctions) were resistant to trans-cleavage by 3C(pro) and 3CD(propol). Interestingly, the VPg/3C(pro) scissile bond (Glu-Ala) was cleaved only by 3CD(propol), and examination of relative cleavage efficiencies revealed significant differences in processing of peptides, indicating differential cleavage patterns for 3C(pro) and 3CD(propol).


Subject(s)
Norovirus/metabolism , Viral Proteins/metabolism , Amino Acid Sequence , Binding Sites/genetics , In Vitro Techniques , Norovirus/genetics , Peptide Fragments/chemistry , Peptide Fragments/genetics , Peptide Fragments/metabolism , Peptide Hydrolases/metabolism , Protein Biosynthesis , Protein Precursors/chemistry , Protein Precursors/genetics , Protein Precursors/metabolism , Protein Processing, Post-Translational , Substrate Specificity , Viral Proteins/chemistry , Viral Proteins/genetics
10.
J Virol ; 81(4): 1858-71, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17121797

ABSTRACT

Sapoviruses are one of the major agents of acute gastroenteritis in childhood. They form a tight genetic cluster (genus) in the Caliciviridae family that regroups both animal and human pathogenic strains. No permissive tissue culture has been developed for human sapovirus, limiting its characterization to surrogate systems. We report here on the first extensive characterization of the key enzyme of replication, the RNA-dependent RNA polymerase (RdRp) associated with the 3D(pol)-like protein. Enzymatically active sapovirus 3D(pol) and its defective mutant were expressed in Escherichia coli and purified. The overall structure of the sapovirus 3D(pol) was determined by X-ray crystallography to 2.32-A resolution. It revealed a right hand fold typical for template-dependent polynucleotide polymerases. The carboxyl terminus is located within the active site cleft, as observed in the RdRp of some (norovirus) but not other (lagovirus) caliciviruses. Sapovirus 3D(pol) prefers Mn(2+) over Mg(2+) but may utilize either as a cofactor in vitro. In a synthetic RNA template-dependent reaction, sapovirus 3D(pol) synthesizes a double-stranded RNA or labels the template 3' terminus by terminal transferase activity. Initiation of RNA synthesis occurs de novo on heteropolymeric templates or in a primer-dependent manner on polyadenylated templates. Strikingly, this mode of initiation of RNA synthesis was also described for norovirus, but not for lagovirus, suggesting structural and functional homologies in the RNA-dependent RNA polymerase of human pathogenic caliciviruses. This first experimental evidence makes sapovirus 3D(pol) an attractive target for developing drugs to control calicivirus infection in humans.


Subject(s)
RNA-Dependent RNA Polymerase/chemistry , RNA-Dependent RNA Polymerase/metabolism , Sapovirus/enzymology , Viral Proteins/chemistry , Viral Proteins/metabolism , Amino Acid Sequence , Binding Sites , Crystallography, X-Ray , Magnesium/metabolism , Manganese/metabolism , Models, Molecular , Molecular Sequence Data , Molecular Structure , RNA, Viral/biosynthesis , Templates, Genetic
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