Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 648
Filter
1.
Nat Geosci ; 17(2): 110-113, 2024.
Article in English | MEDLINE | ID: mdl-38356916

ABSTRACT

Global warming has caused widespread surface lowering of mountain glaciers. By comparing two firn cores collected in 2018 and 2020 from Corbassière glacier in Switzerland, we demonstrate how vulnerable these precious archives of past environmental conditions have become. Within two years, the soluble impurity records were destroyed by melting. The glacier is now irrevocably lost as an archive for reconstructing major atmospheric aerosol components.

3.
BMC Med Educ ; 24(1): 148, 2024 Feb 15.
Article in English | MEDLINE | ID: mdl-38360638

ABSTRACT

BACKGROUND: Cricothyrotomy is an invasive and rare emergency intervention to secure the airway in a "cannot intubate, cannot ventilate" situation. This leads to lack of routine. Cricothyrotomy is performed only hesitantly. Therefore, we aim to improve teaching by including a virtual reality (VR) cricothyrotomy as a learning tool. METHODS: We programmed the VR cricothyrotomy in the C# programming language on the open-source Unity platform. We could include 149 students that we randomly assigned to either a study group (VR cricothyrotomy) or control group (educational video). We asked the study group to subjectively rate the VR cricothyrotomy. To evaluate our intervention (VR cricothyrotomy) we took the time participants needed to perform a cricothyrotomy on a plastic model of a trachea and evaluated the correct procedural steps. RESULTS: The majority of students that performed the VR simulation agreed that they improved in speed (81%) and procedural steps (92%). All participants completed the cricothyrotomy in 47s ± 16s and reached a total score of 8.7 ± 0.7 of 9 possible points. We saw no significant difference in time needed to perform a cricothyrotomy between study and control group (p > 0.05). However, the total score of correct procedural steps was significantly higher in the study group than in the control group (p < 0.05). CONCLUSIONS: Virtual reality is an innovative learning tool to improve teaching of emergency procedures. The VR cricothyrotomy subjectively and objectively improved correct procedural steps. Digitized education fills an educational gap between pure haptic experience and theoretical knowledge. This is of great value when focusing on extension of factual knowledge. TRIAL REGISTRATION: DRKS00031736, registered on the 20th April 2023.


Subject(s)
Gamification , Laryngectomy , Simulation Training , Virtual Reality , Humans , Case-Control Studies , Learning , Simulation Training/methods , Laryngeal Muscles/surgery
4.
Sci Rep ; 12(1): 17590, 2022 Oct 20.
Article in English | MEDLINE | ID: mdl-36266367

ABSTRACT

Within this work, we demonstrate in-situ alignment of the easy axis single-crystal magnetic particles inside a polymer matrix using fused filament fabrication. Two different magnetic materials are investigated: (i) Strontium hexaferrite inside a PA6 matrix, fill grade: 49 vol% and (ii) Samarium iron nitride inside a PA12 matrix, fill grade: 44 vol%. In the presence of the external alignment field, the strontium hexaferrite particles inside the PA6 matrix can be well aligned with a ratio of remnant magnetization to saturation magnetization in an easy axis of 0.7. No significant alignment for samarium iron nitride could be achieved. The results show the feasibility to fabricate magnets with arbitrary and locally defined easy axis using fused filament fabrication since the permanent magnets (or alternatively an electromagnet) can be mounted on a rotatable platform.

6.
Ann Oncol ; 32(5): 609-619, 2021 05.
Article in English | MEDLINE | ID: mdl-33610734

ABSTRACT

BACKGROUND: Claudin 18.2 (CLDN18.2) is contained within normal gastric mucosa epithelial tight junctions; upon malignant transformation, CLDN18.2 epitopes become exposed. Zolbetuximab, a chimeric monoclonal antibody, mediates specific killing of CLDN18.2-positive cells through immune effector mechanisms. PATIENTS AND METHODS: The FAST study enrolled advanced gastric/gastro-oesophageal junction and oesophageal adenocarcinoma patients (aged ≥18 years) with moderate-to-strong CLDN18.2 expression in ≥40% tumour cells. Patients received first-line epirubicin + oxaliplatin + capecitabine (EOX, arm 1, n = 84) every 3 weeks (Q3W), or zolbetuximab + EOX (loading dose, 800 mg/m2 then 600 mg/m2 Q3W) (arm 2, n = 77). Arm 3 (exploratory) was added after enrolment initiation (zolbetuximab + EOX 1000 mg/m2 Q3W, n = 85). The primary endpoint was progression-free survival (PFS) and overall survival (OS) was a secondary endpoint. RESULTS: In the overall population, both PFS [hazard ratio (HR) = 0.44; 95% confidence interval (CI), 0.29-0.67; P < 0.0005] and OS (HR = 0.55; 95% CI, 0.39-0.77; P < 0.0005) were significantly improved with zolbetuximab + EOX (arm 2) compared with EOX alone (arm 1). This significant PFS benefit was retained in patients with moderate-to-strong CLDN18.2 expression in ≥70% of tumour cells (HR = 0.38; 95% CI, 0.23-0.62; P < 0.0005). Significant improvement in PFS was also reported in the overall population of arm 3 versus arm 1 (HR = 0.58; 95% CI, 0.39-0.85; P = 0.0114) but not in high CLDN18.2-expressing patients; no significant improvement in OS was observed in either population. Most adverse events (AEs) related to zolbetuximab + EOX (nausea, vomiting, neutropenia, anaemia) were grade 1-2. Grade ≥3 AEs showed no substantial increases overall (zolbetuximab + EOX versus EOX alone). CONCLUSIONS: In advanced gastric/gastro-oesophageal junction and oesophageal adenocarcinoma patients expressing CLDN18.2, adding zolbetuximab to first-line EOX provided longer PFS and OS versus EOX alone. Zolbetuximab + EOX was generally tolerated and AEs were manageable. Zolbetuximab 800/600 mg/m2 is being evaluated in phase III studies based on clinical benefit observed in the overall population and in patients with moderate-to-strong CLDN18.2 expression in ≥70% of tumour cells.


Subject(s)
Adenocarcinoma , Esophageal Neoplasms , Stomach Neoplasms , Adenocarcinoma/drug therapy , Adolescent , Adult , Antibodies, Monoclonal/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Capecitabine/therapeutic use , Claudins/genetics , Claudins/therapeutic use , Esophageal Neoplasms/drug therapy , Esophagogastric Junction , Humans , Stomach Neoplasms/drug therapy
7.
Article in English | MEDLINE | ID: mdl-33557269

ABSTRACT

Contact tracing is one of the oldest social network health interventions used to reduce the diffusion of various infectious diseases. However, some infectious diseases like COVID-19 amass at such a great scope that traditional methods of conducting contact tracing (e.g., face-to-face interviews) remain difficult to implement, pointing to the need to develop reliable and valid survey approaches. The purpose of this research is to test the effectiveness of three different egocentric survey methods for extracting contact tracing data: (1) a baseline approach, (2) a retrieval cue approach, and (3) a context-based approach. A sample of 397 college students were randomized into one condition each. They were prompted to anonymously provide contacts and populated places visited from the past four days depending on what condition they were given. After controlling for various demographic, social identity, psychological, and physiological variables, participants in the context-based condition were significantly more likely to recall more contacts (medium effect size) and places (large effect size) than the other two conditions. Theoretically, the research supports suggestions by field theory that assume network recall can be significantly improved by activating relevant activity foci. Practically, the research contributes to the development of innovative social network data collection methods for contract tracing survey instruments.


Subject(s)
Contact Tracing/methods , Social Networking , COVID-19 , Humans , Random Allocation
9.
Ann Oncol ; 30(9): 1487-1495, 2019 09 01.
Article in English | MEDLINE | ID: mdl-31240302

ABSTRACT

BACKGROUND: Claudin 18.2 (CLDN18.2) is physiologically confined to gastric mucosa tight junctions; however, upon malignant transformation, perturbations in cell polarity lead to CLDN18.2 epitopes being exposed on the cancer cell surface. The first-in-class monoclonal antibody, zolbetuximab (formerly known as IMAB362), binds to CLDN18.2 and can induce immune-mediated lysis of CLDN18.2-positive cells. PATIENTS AND METHODS: Patients with advanced gastric, gastro-oesophageal junction (GEJ) or oesophageal adenocarcinomas with moderate-to-strong CLDN18.2 expression in ≥50% of tumour cells received zolbetuximab intravenously every 2 weeks for five planned infusions. At least three patients were enrolled in two sequential cohorts (cohort 1300 mg/m2; cohort 2600 mg/m2); additional patients were enrolled into a dose-expansion cohort (cohort 3600 mg/m2). The primary end point was the objective response rate [ORR: complete and partial response (PR)]; secondary end points included clinical benefit [ORR+stable disease (SD)], progression-free survival, safety/tolerability, and zolbetuximab pharmacokinetic profile. RESULTS: From September 2010 to September 2012, 54 patients were enrolled (cohort 1, n = 4; cohort 2, n = 6; cohort 3, n = 44). Three patients in cohort 1 and 25 patients in cohorts 2/3 received at least 5 infusions. Antitumour activity data were available for 43 patients, of whom 4 achieved PR (ORR 9%) and 6 (14%) had SD for a clinical benefit rate of 23%. In a subgroup of patients with moderate-to-high CLDN18.2 expression in ≥70% of tumour cells, ORR was 14% (n = 4/29). Treatment-related adverse events occurred in 81.5% (n = 44/54) patients; nausea (61%), vomiting (50%), and fatigue (22%) were the most frequent. CONCLUSIONS: Zolbetuximab monotherapy was well tolerated and exhibited antitumour activity in patients with CLDN18.2-positive advanced gastric or GEJ adenocarcinomas, with response rates similar to those reported for single-agent targeted agents in gastric/GEJ cancer trials. CLINICALTRIALS.GOV NUMBER: NCT01197885.


Subject(s)
Adenocarcinoma/drug therapy , Antibodies, Monoclonal/administration & dosage , Esophageal Neoplasms/drug therapy , Stomach Neoplasms/drug therapy , Adenocarcinoma/immunology , Adenocarcinoma/pathology , Aged , Antibodies, Monoclonal/adverse effects , Drug-Related Side Effects and Adverse Reactions/classification , Drug-Related Side Effects and Adverse Reactions/pathology , Esophageal Neoplasms/immunology , Esophageal Neoplasms/pathology , Esophagogastric Junction/drug effects , Esophagogastric Junction/pathology , Female , Humans , Male , Middle Aged , Neoplasm Recurrence, Local/drug therapy , Neoplasm Recurrence, Local/pathology , Stomach Neoplasms/immunology , Stomach Neoplasms/pathology , Treatment Outcome
10.
Int J Legal Med ; 133(2): 325-334, 2019 Mar.
Article in English | MEDLINE | ID: mdl-29797283

ABSTRACT

Some STR loci have internal sequence variations, which are not revealed by the standard STR typing methods used in forensic genetics (PCR and fragment length analysis by capillary electrophoresis (CE)). Typing of STRs with next-generation sequencing (NGS) uncovers the sequence variation in the repeat region and in the flanking regions. In this study, 363 Danish individuals were typed for 56 STRs (26 autosomal STRs, 24 Y-STRs, and 6 X-STRs) using the ForenSeq™ DNA Signature Prep Kit to establish a Danish STR sequence database. Increased allelic diversity was observed in 34 STRs by the PCR-NGS assay. The largest increases were found in DYS389II and D12S391, where the numbers of sequenced alleles were around four times larger than the numbers of alleles determined by repeat length alone. Thirteen SNPs and one InDel were identified in the flanking regions of 12 STRs. Furthermore, 36 single positions and five longer stretches in the STR flanking regions were found to have dubious genotyping quality. The combined match probability of the 26 autosomal STRs was 10,000 times larger using the PCR-NGS assay than by using PCR-CE. The typical paternity indices for trios and duos were 500 and 100 times larger, respectively, than those obtained with PCR-CE. The assay also amplified 94 SNPs selected for human identification. Eleven of these loci were not in Hardy-Weinberg equilibrium in the Danish population, most likely because the minimum threshold for allele calling (30 reads) in the ForenSeq™ Universal Analysis Software was too low and frequent allele dropouts were not detected.


Subject(s)
DNA Fingerprinting , Databases, Nucleic Acid , Microsatellite Repeats , Sequence Analysis, DNA/instrumentation , Sequence Analysis, DNA/methods , Alleles , Denmark , Female , Genetics, Population , Genotype , Haplotypes , Humans , INDEL Mutation , Male , Polymerase Chain Reaction , Polymorphism, Single Nucleotide
12.
Eur Psychiatry ; 48: 51-57, 2018 02.
Article in English | MEDLINE | ID: mdl-29331599

ABSTRACT

BACKGROUND: Psychiatric inpatient treatment is increasingly performed in settings with locked doors. However, locked wards have well-known disadvantages and are ethically problematic. In addition, recent data challenges the hypothesis that locked wards provide improved safety over open-door settings regarding suicide, absconding and aggression. Furthermore, there is evidence that the introduction of an open-door policy may lead to short-term reductions in involuntary measures. The aim of this study was to assess if the introduction of an open-door policy is associated with a long-term reduction of the frequency of seclusion and forced medication. METHOD: In this 6-year, hospital-wide, longitudinal, observational study, we examined the frequency of seclusion and forced medication in 17,359 inpatient cases admitted to the Department of Adult Psychiatry, Universitäre Psychiatrische Kliniken (UPK) Basel, University of Basel, Switzerland. In an approach to enable a less restrictive policy, six previously closed psychiatric wards were permanently opened beginning from August 2011. During this process, a systematic change towards a more patient-centered and recovery-oriented care was applied. Statistical analysis consisted of generalized estimating equations (GEE) models. RESULTS: In multivariate analyses controlling for potential confounders, the implementation of an open-door policy was associated with a continuous reduction of seclusion (from 8.2 to 3.5%; ηp2=0.82; odds ratio: 0.88) and forced medication (from 2.4 to 1.2%; ηp2=0.70; odds ratio: 0.90). CONCLUSION: This underlines the potential of the introduction of an open-door policy to attain a long-term reduction in involuntary measures.


Subject(s)
Mental Disorders/drug therapy , Patient Isolation , Policy , Psychiatric Department, Hospital , Adult , Aggression/psychology , Female , Hospitalization , Humans , Inpatients/psychology , Longitudinal Studies , Male , Mental Disorders/psychology , Middle Aged , Restraint, Physical/psychology , Suicide/psychology , Switzerland
13.
Sci Rep ; 7(1): 16638, 2017 11 30.
Article in English | MEDLINE | ID: mdl-29192156

ABSTRACT

Worldwide, more than 1 billion people suffer from allergic diseases. However, until now it is not fully understood how certain proteins can induce allergic immune responses, while others cannot. Studies suggest that allergenicity is a process not only determined by properties of the allergen itself but also by costimulatory factors, that are not classically associated with allergic reactions. To investigate the allergenicity of the major birch pollen allergen Bet v 1 and the impact of adjuvants associated with pollen, e.g. lipopolysaccharide (LPS), we performed quantitative proteome analysis to study the activation of monocyte-derived dendritic cells (moDCs). Thus, we treated cells with birch pollen extract (BPE), recombinant Bet v 1, and LPS followed by proteomic profiling via high-performance liquid chromatography and tandem mass spectrometry (HPLC-MS/MS) using isobaric labelling. Enrichment and pathway analysis revealed the influence of regulated proteins especially in cytokine signalling and dendritic cell activation. We found highly regulated, but differentially expressed proteins after treatment with BPE and LPS, whereas the cellular response to Bet v 1 was limited. Our findings lead to the conclusion that Bet v 1 needs a specific "allergen context" involving cofactors apart from LPS to induce an immune response in human moDCs.


Subject(s)
Allergens/immunology , Dendritic Cells/immunology , Dendritic Cells/metabolism , Proteome , Proteomics , Analysis of Variance , Biomarkers , Computational Biology/methods , Cytokines/metabolism , Cytotoxicity, Immunologic , Gene Ontology , Humans , Hypersensitivity/immunology , Hypersensitivity/metabolism , Immunophenotyping , Lipopolysaccharides/immunology , Molecular Sequence Annotation , NF-kappa B/metabolism , Proteomics/methods
14.
J Pharm Biomed Anal ; 143: 147-158, 2017 Sep 05.
Article in English | MEDLINE | ID: mdl-28599168

ABSTRACT

For the first time, a comprehensive investigation of the impurity profile of the synthetic thyroid API (active pharmaceutical ingredient) liothyronine sodium (LT3Na) was performed by using reversed phase HPLC and advanced structural elucidation techniques including high resolution tandem mass spectrometry (HRMS/MS) and on-line hydrogen-deuterium (H/D) exchange. Overall, 39 compounds were characterized and 25 of these related substances were previously unknown to literature. The impurity classification system recently developed for the closely related API levothyroxine sodium (LT4Na) could be applied to the newly characterized liothyronine sodium impurities resulting in a wholistic thyroid API impurity classification system. Furthermore, the mass-spectrometric CID-fragmentation of specific related substances was discussed and rationalized by detailed fragmentation pathways. Moreover, the UV/Vis absorption characteristics of the API and selected impurities were investigated to corroborate chemical structure assignments derived from MS data.


Subject(s)
Triiodothyronine/analysis , Chromatography, High Pressure Liquid , Deuterium , Drug Contamination , Hydrogen , Mass Spectrometry , Sodium
15.
Clin Genet ; 91(6): 868-880, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28229453

ABSTRACT

The group of chondrodysplasia with multiple dislocations includes several entities, characterized by short stature, dislocation of large joints, hand and/or vertebral anomalies. Other features, such as epiphyseal or metaphyseal changes, cleft palate, intellectual disability are also often part of the phenotype. In addition, several conditions with overlapping features are related to this group and broaden the spectrum. The majority of these disorders have been linked to pathogenic variants in genes encoding proteins implicated in the synthesis or sulfation of proteoglycans (PG). In a series of 30 patients with multiple dislocations, we have performed exome sequencing and subsequent targeted analysis of 15 genes, implicated in chondrodysplasia with multiple dislocations, and related conditions. We have identified causative pathogenic variants in 60% of patients (18/30); when a clinical diagnosis was suspected, this was molecularly confirmed in 53% of cases. Forty percent of patients remain without molecular etiology. Pathogenic variants in genes implicated in PG synthesis are of major importance in chondrodysplasia with multiple dislocations and related conditions. The combination of hand features, growth failure severity, radiological aspects of long bones and of vertebrae allowed discrimination among the different conditions. We propose key diagnostic clues to the clinician.


Subject(s)
Intellectual Disability/genetics , Musculoskeletal Abnormalities/genetics , Osteochondrodysplasias/genetics , Adolescent , Adult , Child , Child, Preschool , Female , Genetic Association Studies , Humans , Infant , Infant, Newborn , Intellectual Disability/diagnosis , Intellectual Disability/diagnostic imaging , Intellectual Disability/physiopathology , Male , Musculoskeletal Abnormalities/diagnosis , Musculoskeletal Abnormalities/diagnostic imaging , Musculoskeletal Abnormalities/physiopathology , Osteochondrodysplasias/diagnosis , Osteochondrodysplasias/diagnostic imaging , Osteochondrodysplasias/physiopathology , Radiography , Exome Sequencing
16.
Clin Microbiol Infect ; 23(1): 48.e1-48.e7, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27615716

ABSTRACT

OBJECTIVES: To investigate the prevalence and risk factors for asymptomatic toxigenic (TCD) and nontoxigenic Clostridium difficile (NTCD) colonization in a broad cross section of the general hospital population over a 3-year period. METHODS: Patients without diarrhoea admitted to two Australian tertiary hospitals were randomly selected through six repeated cross-sectional surveys conducted between 2012 and 2014. Stool specimens were cultured under anaerobic conditions, and C. difficile isolates were tested for the presence of toxin genes and ribotyped. Patients were then grouped into noncolonized, TCD colonized or NTCD colonized for identifying risk factors using multinomial logistic regression models. RESULTS: A total of 1380 asymptomatic patients were enrolled; 76 patients (5.5%) were TCD colonized and 28 (2.0%) were NTCD colonized. There was a decreasing annual trend in TCD colonization, and asymptomatic colonization was more prevalent during the summer than winter months. TCD colonization was associated with gastro-oesophageal reflux disease (relative risk ratio (RRR) = 2.20; 95% confidence interval (CI) 1.17-4.14), higher number of admissions in the previous year (RRR = 1.24; 95% CI 1.10-1.39) and antimicrobial exposure during the current admission (RRR = 2.78; 95% CI 1.23-6.28). NTCD colonization was associated with chronic obstructive pulmonary disease (RRR = 3.88; 95% CI 1.66-9.07) and chronic kidney failure (RRR = 5.78; 95% CI 2.29-14.59). Forty-eight different ribotypes were identified, with 014/020 (n = 23), 018 (n = 10) and 056 (n = 6) being the most commonly isolated. CONCLUSIONS: Risk factors differ between patients with asymptomatic colonization by toxigenic and nontoxigenic strains. Given that morbidity is largely driven by toxigenic strains, this novel finding has important implications for disease control and prevention.


Subject(s)
Carrier State , Clostridioides difficile/isolation & purification , Hospitals , Adult , Aged , Aged, 80 and over , Australia/epidemiology , Clostridium Infections/epidemiology , Clostridium Infections/microbiology , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Risk Factors , Seasons
17.
J Pharm Biomed Anal ; 135: 140-152, 2017 Feb 20.
Article in English | MEDLINE | ID: mdl-28024262

ABSTRACT

The structural elucidation of unknown pharmaceutical impurities plays an important role in the quality control of newly developed and well-established active pharmaceutical ingredients (APIs). The United States Pharmacopeia (USP) monograph for the API Levothyroxine Sodium, a synthetic thyroid hormone, features two high pressure liquid chromatography (HPLC) methods using UV-VIS absorption detection to determine organic impurities in the drug substance. The impurity profile of the first USP method ("Procedure 1") has already been extensively studied, however for the second method ("Procedure 2"), which exhibits a significantly different impurity profile, no wholistic structural elucidation of impurities has been performed yet. Applying minor modifications to the chromatographic parameters of USP "Procedure 2" and using various comprehensive structural elucidation methods such as high resolution tandem mass spectrometry with on-line hydrogen-deuterium (H/D) exchange or two-dimensional nuclear magnetic resonance spectroscopy (NMR) we gained new insights about the complex impurity profile of the synthetic thyroid hormone. This resulted in the characterization of 24 compounds previously unknown to literature and the introduction of two new classes of Levothyroxine Sodium impurities. Five novel compounds were unambiguously identified via isolation or synthesis of reference substances and subsequent NMR spectroscopic investigation. Additionally, Collision-Induced Dissociation (CID)-type fragmentation of identified major impurities as well as neutral loss fragmentation patterns of many characterized impurities were discussed.


Subject(s)
Deuterium Exchange Measurement/methods , Drug Contamination , Magnetic Resonance Spectroscopy/methods , Tandem Mass Spectrometry/methods , Thyroxine/analysis , Thyroxine/chemical synthesis , Chromatography, High Pressure Liquid/methods , Mass Spectrometry/methods
19.
Opt Express ; 24(8): 8214-27, 2016 Apr 18.
Article in English | MEDLINE | ID: mdl-27137260

ABSTRACT

The performance of the knife-edge method as a beam profiling technique for tightly focused light beams depends on several parameters, such as the material and height of the knife-pad as well as the polarization and wavelength of the focused light beam under study. Here we demonstrate that the choice of the substrate the knife-pads are fabricated on has a crucial influence on the reconstructed beam projections as well. We employ an analytical model for the interaction of the knife-pad with the beam and report good agreement between our numerical and experimental results. Moreover, we simplify the analytical model and demonstrate, in which way the underlying physical effects lead to the apparent polarization dependent beam shifts and changes of the beamwidth for different substrate materials and heights of the knife-pad.

20.
Planta Med ; 82(11-12): 973-85, 2016 Jul.
Article in English | MEDLINE | ID: mdl-27220077

ABSTRACT

The X-linked inhibitor of apoptosis protein is a cellular protein that inhibits the activity of mammalian caspases and promotes resistance to apoptosis. The ethanol extract of the aerial parts of Ephedra sinica has been identified to possess inhibitory activity of the X-linked inhibitor of apoptosis protein by an in vitro fluorescence polarization assay using the BIR3 domain of the X-linked inhibitor of apoptosis protein. Bioactivity-guided fractionation identified proanthocyanidin-enriched fractions as the active principles. The most active fraction showed an IC50 value of 27.3 µg/mL (CI95: 25.9-28.9 µg/mL) corresponding to 9.6 µM (CI95: 9.1-10.1 µM) calculated by the use of the determined average molecular weight of 2853.5. Samples were analyzed by a thiolytic degradation/HPLC-MS assay, UHPLC-HRMS, and 1D NMR.The thiolytic degradation/HPLC-MS assay revealed a mean degree of polymerization of 9.5 ± 0.2 units (calculated average MW 2853.5) for the active fraction and 11.4 ± 0.6 units (calculated average MW 3437.0) for the most related inactive fraction. Chemical characterization identified (epi)gallocatechin (76.6 ± 1.0 % active; 80.7 ± 2.7 % inactive sample) and (epi)catechin units as building blocks. Interestingly, the investigated proanthocyanidins turned out to be a complex mixture of double linked A-type (binding 2-O-7″, 4-6″) and single linked B-type units.This study identified oligomeric proanthocyanidins as active principles of E. sinica in vitro by a fluorescence polarization assay and via protein fragment complementation analysis.


Subject(s)
Ephedra sinica/chemistry , Plant Extracts/pharmacology , Proanthocyanidins/pharmacology , X-Linked Inhibitor of Apoptosis Protein/antagonists & inhibitors , Fluorescence Polarization , HEK293 Cells , Humans , Plant Components, Aerial/chemistry , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Proanthocyanidins/chemistry , Proanthocyanidins/isolation & purification , Protein Binding , Protein Domains
SELECTION OF CITATIONS
SEARCH DETAIL
...