77 research outputs found
Glycosylation is a key in SARS-CoV-2 infection
SARS-CoV-2 causes the respiratory syndrome COVID-19 and is responsible for the current pandemic. The S protein of SARS-CoV-2-mediating virus binding to target cells and subsequent viral uptake is extensively glycosylated. Here we focus on how glycosylation of both SARS-CoV-2 and target cells crucially impacts SARS-CoV-2 infection at different levels: (1) virus binding and entry to host cells, with glycosaminoglycans of host cells acting as a necessary co-factor for SARS-CoV-2 infection by interacting with the receptor-binding domain of the SARS-CoV-2 spike glycoprotein, (2) innate and adaptive immune response where glycosylation plays both a protective role and contributes to immune evasion by masking of viral polypeptide epitopes and may add to the cytokine cascade via non-fucosylated IgG, and (3) therapy and vaccination where a monoclonal antibody-neutralizing SARS-CoV-2 was shown to interact also with a distinct glycan epitope on the SARS-CoV-2 spike protein. These evidences highlight the importance of ensuring that glycans are considered when tackling this disease, particularly in the development of vaccines, therapeutic strategies and serological testing
Vertrauen, Optimismus und ErNeuerung: der VON-Index zur Messung von VerÀnderungsbereitschaft in Transformationsgesellschaften
'Der Artikel verfolgt das Ziel, die Erfahrungen und EinschĂ€tzungen der Bevölkerungen in Kroatien, Serbien und Montenegro sowie Bosnien und Herzegowina auf dem Weg zur Entwicklung einer Demokratie mit Hilfe eines so genannten VON-Indexes (der sich auf Vertrauen, Entwicklungsoptimismus und Erneuerungsbereitschaft bezieht) darzustellen und zu bewerten. ErgĂ€nzt werden die Ergebnisse durch qualitatives Datenmaterial aus ExpertInnenbefragungen und Fokusgruppeninterviews. Nach KlĂ€rung der Fragestellung wird der VON-Index vorgestellt und erlĂ€utert. AnschlieĂend folgt die Darstellung der AusprĂ€gungen des VON-Indexes, wobei sich hohe, ambivalente und geringe VerĂ€nderungsbereitschaft unterscheiden lassen. Diese Differenzierung dient in der Folge als Grundlage fĂŒr die Bildung von drei Bevölkerungsgruppen mit unterschiedlichen Stimmungslagen. Diese Gruppen werden in Bezug auf soziale Merkmale und Einstellungen der Befragten nĂ€her analysiert. Der LĂ€ndervergleich zeigt die KomplexitĂ€t der Bevölkerungseinstellungen zur kĂŒnftigen Entwicklung der drei Staaten, wobei auch jeweilige historische Besonderheiten zu berĂŒcksichtigen sind.' (Autorenreferat)'The article analyses the public in Croatia, Serbia and Montenegro and Bosnia and Herzegovina on their way to democracy, by measuring experiences and attitudes with the so-called VON-index. VON refers to trust, optimism for development, and readiness for renewal. Quantitative survey data are supplemented with information from expert and focus group interviews. After introducing the research question, the VON-index based measurement is explained and results are being presented. We can distinguish between a high, an ambivalent and a low readiness for change. Referring to these different types, and acknowledging social characteristics and public sentiments, the complexity of attitudes of the public for the future development of these three states is displayed, also reflecting the concrete historical context.' (author's abstract)
Interaction of human dipeptidyl peptidase IV and human immunodeficiency virus type-1 transcription transactivator in Sf9 cells
<p>Abstract</p> <p>Background</p> <p>Dipeptidyl peptidase IV (DPPIV) also known as the T cell activation marker CD26 is a multifunctional protein which is involved in various biological processes. The association of human-DPPIV with components of the human immunodeficiency virus type-1 (HIV1) is well documented and raised some discussions. Several reports implicated the interaction of human-DPPIV with the HIV1 transcription transactivator protein (HIV1-Tat) and the inhibition of the dipeptidyl peptidase activity of DPPIV by the HIV1-Tat protein. Furthermore, enzyme kinetic data implied another binding site for the HIV1-Tat other than the active centre of DPPIV. However, the biological significance of this interaction of the HIV1-Tat protein and human-DPPIV has not been studied, yet. Therefore, we focused on the interaction of HIV1-Tat protein with DPPIV and investigated the subsequent biological consequences of this interaction in <it>Spodoptera frugiperda </it>cells, using the BAC-TO-BAC baculovirus system.</p> <p>Results</p> <p>The HIV1-Tat protein (Tat-<it>BRU</it>) co-localized and co-immunoprecipitated with human-DPPIV protein, following co-expression in the baculovirus-driven <it>Sf9 </it>cell expression system. Furthermore, tyrosine phosphorylation of DPPIV protein was up-regulated in Tat/DPPIV-co-expressing cells after 72 h culturing and also in DPPIV-expressing <it>Sf9 </it>cells after application of purified recombinant Tat protein. As opposed to the expression of Tat alone, serine phosphorylation of the Tat protein was decreased when co-expressed with human-DPPIV protein.</p> <p>Conclusions</p> <p>We show for the first time that human-DPPIV and HIV1-Tat co-immunoprecipitate. Furthermore, our findings indicate that the interaction of HIV1-Tat and human-DPPIV may be involved in signalling platforms that regulate the biological function of both human-DPPIV and HIV1-Tat.</p
High prevalence of anti-HCV antibodies in two metropolitan emergency departments in Germany : a prospective screening analysis of 28,809 patients
Background and Aims: The prevalence of hepatitis C virus (HCV) antibodies in Germany has been estimated to be in the range of 0.4â0.63%. Screening for HCV is recommended in patients with elevated ALT levels or significant risk factors for HCV transmission only. However, 15â30% of patients report no risk factors and ALT levels can be normal in up to 20â30% of patients with chronic HCV infection. The aim of this study was to assess the HCV seroprevalence in patients visiting two tertiary care emergency departments in Berlin and Frankfurt, respectively.
Methods: Between May 2008 and March 2010, a total of 28,809 consecutive patients were screened for the presence of anti-HCV antibodies. Anti-HCV positive sera were subsequently tested for HCV-RNA.
Results: The overall HCV seroprevalence was 2.6% (95% CI: 2.4â2.8; 2.4% in Berlin and 3.5% in Frankfurt). HCV-RNA was detectable in 68% of anti-HCV positive cases. Thus, the prevalence of chronic HCV infection in the overall study population was 1.6% (95% CI 1.5â1.8). The most commonly reported risk factor was former/current injection drug use (IDU; 31.2%) and those with IDU as the main risk factor were significantly younger than patients without IDU (p<0.001) and the male-to-female ratio was 72% (121 vs. 46 patients; p<0.001). Finally, 18.8% of contacted HCV-RNA positive patients had not been diagnosed previously.
Conclusions: The HCV seroprevalence was more than four times higher compared to current estimates and almost one fifth of contacted HCV-RNA positive patients had not been diagnosed previously
Cupulin Is a Zona Pellucida-Like Domain Protein and Major Component of the Cupula from the Inner Ear
The extracellular membranes of the inner ear are essential constituents to
maintain sensory functions, the cupula for sensing torsional movements of the
head, the otoconial membrane for sensing linear movements and accelerations
like gravity, and the tectorial membrane in the cochlea for hearing. So far a
number of structural proteins have been described, but for the gelatinous
cupula precise data are missing. Here, we describe for the first time a major
proteinogenic component of the cupula structure with an apparent molecular
mass of 45 kDa from salmon. Analyses of respective peptides revealed highly
conserved amino-acid sequences with identity to zona pellucida-like domain
proteins. Immunohistochemistry studies localized the protein in the ampulla of
the inner ear from salmon and according to its anatomical appearance we
identified this glycoprotein as Cupulin. Future research on structure and
function of zona pellucida-like domain proteins will enhance our knowledge of
inner ear diseases, like sudden loss of vestibular function and other
disturbances
Fibrinogen and factor XIII A-subunit genotypes interactively influence C-reactive protein levels during inflammation
Fibrinogen is a target of autoimmune reactions in rheumatoid arthritis (RA). Fibrin(ogen) derivatives are involved in inflammatory processes and the generation of a stable fibrin network is necessary for sufficient inflammation control. As the density and stability of fibrin networks depend on complex interactions between factor XIIIA (F13A) and fibrinogen genotypes, the authors studied whether these genotypes were related to C-reactive protein (CRP) levels during acute-phase reactions
Pooling, room temperature, and extended storage time increase the release of adultâspecific biologic response modifiers in platelet concentrates: a hidden transfusion risk for neonates?
BACKGROUND: Adult donor platelets (PLTs) are frequently transfused to prevent or stop bleeding in neonates with thrombocytopenia. There is evidence for PLT transfusion-related morbidity and mortality, leading to the hypothesis on immunomodulatory effects of transfusing adult PLTs into neonates. Candidate factors are biologic response modifiers (BRMs) that are expressed at higher rates in adult than in neonatal PLTs. This study investigated whether storage conditions or preparation methods impact on the release of those differentially expressed BRMs.
STUDY DESIGN AND METHODS: Pooled PLT concentrates (PCs) and apheresis PCs (APCs) were stored under agitation for up to 7 days at room temperature (RT) or at 2 to 8 degrees C. The BRMs CCL5/RANTES, TGF beta 1, TSP1, and DKK1 were measured in PCs' supernatant, lysate, and corresponding plasma. PLT function was assessed by light transmission aggregometry.
RESULTS: Concerning the preparation method, higher concentrations of DKK1 were found in pooled PCs compared to APCs. In supernatants, the concentrations of CCL5, TGF beta 1, TSP1, and DKK1 significantly increased, both over standard (†4 days) and over extended storage times (7 days). Each of the four BRMs showed an up to twofold increase in concentration after storage at RT compared to cold storage (CS). There was no difference in the aggregation capacity.
CONCLUSION: This analysis shows that the release of adult-specific BRMs during storage is lowest in short- and CS APCs. Our study points to strategies for reducing the exposure of sick neonates to BRMs that can be specifically associated to PLT transfusion-related morbidity
Fibrinogen and factor XIII A-subunit genotypes interactively influence C-reactive protein levels during inflammation
Fibrinogen is a target of autoimmune reactions in rheumatoid arthritis (RA). Fibrin(ogen) derivatives are involved in inflammatory processes and the generation of a stable fibrin network is necessary for sufficient inflammation control. As the density and stability of fibrin networks depend on complex interactions between factor XIIIA (F13A) and fibrinogen genotypes, the authors studied whether these genotypes were related to C-reactive protein (CRP) levels during acute-phase reactions
HE4 as a serum biomarker for the diagnosis of pelvic masses: a prospective, multicenter study in 965 patients
Background: To evaluate the diagnostic value of adding human epididymis protein 4 (HE4), cancer antigen 125 (CA125) and risk of malignancy algorithm (ROMA) to ultrasound for detecting ovarian cancer in patients with a pelvic mass.
Methods: This was a prospective, observational, multicenter study. Patients aged > 18 years who were scheduled to undergo surgery for a suspicious pelvic mass had CA125 and HE4 levels measured prior to surgery, in addition to a routine transvaginal ultrasound scan. The diagnostic performance of CA125, HE4 and ROMA for distinguishing between benign and malignant adnexal masses was assessed using receiver operating characteristic (ROC) analysis and the corresponding area under the curve (AUC).
Results: Of 965 evaluable patients, 804 were diagnosed with benign tumors and 161 were diagnosed with ovarian cancer. In late-stage ovarian cancer, CA125, HE4 and ROMA all had an excellent diagnostic performance (AUC > 0.92), whereas in stage I and II, diagnostic performance of all three biomarkers was less adequate (AUC < 0.77). In the differential diagnosis of ovarian cancer and endometriosis, ROMA and HE4 performed better than CA125 with 99 and 98.1% versus 75.0% sensitivity, respectively, at 75.4% specificity.
Conclusions: ROMA and HE4 could be valuable biomarkers to help with the diagnosis of ovarian cancer in premenopausal patients in order to differentiate from endometriosis, whereas CA125 may be more adequate for postmenopausal patients
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