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1.
Emerg Infect Dis ; 27(8): 2174-2178, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34102097

RESUMO

We detected delayed and reduced antibody and T-cell responses after BNT162b2 vaccination in 71 elderly persons (median age 81 years) compared with 123 healthcare workers (median age 34 years) in Germany. These data emphasize that nonpharmaceutical interventions for coronavirus disease remain crucial and that additional immunizations for the elderly might become necessary.


Assuntos
COVID-19 , Adulto , Idoso , Idoso de 80 Anos ou mais , Vacinas contra COVID-19 , Alemanha/epidemiologia , Humanos , SARS-CoV-2 , Linfócitos T , Vacinação
2.
Crit Care Med ; 49(10): 1664-1673, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34166284

RESUMO

OBJECTIVES: The rapid diagnosis of acute infections and sepsis remains a serious challenge. As a result of limitations in current diagnostics, guidelines recommend early antimicrobials for suspected sepsis patients to improve outcomes at a cost to antimicrobial stewardship. We aimed to develop and prospectively validate a new, 29-messenger RNA blood-based host-response classifier Inflammatix Bacterial Viral Non-Infected version 2 (IMX-BVN-2) to determine the likelihood of bacterial and viral infections. DESIGN: Prospective observational study. SETTING: Emergency Department, Campus Benjamin Franklin, Charité-Universitätsmedizin Berlin, Germany. PATIENTS: Three hundred twelve adult patients presenting to the emergency department with suspected acute infections or sepsis with at least one vital sign change. INTERVENTIONS: None (observational study only). MEASUREMENTS AND MAIN RESULTS: Gene expression levels from extracted whole blood RNA was quantified on a NanoString nCounter SPRINT (NanoString Technologies, Seattle, WA). Two predicted probability scores for the presence of bacterial and viral infection were calculated using the IMX-BVN-2 neural network classifier, which was trained on an independent development set. The IMX-BVN-2 bacterial score showed an area under the receiver operating curve for adjudicated bacterial versus ruled out bacterial infection of 0.90 (95% CI, 0.85-0.95) compared with 0.89 (95% CI, 0.84-0.94) for procalcitonin with procalcitonin being used in the adjudication. The IMX-BVN-2 viral score area under the receiver operating curve for adjudicated versus ruled out viral infection was 0.83 (95% CI, 0.77-0.89). CONCLUSIONS: IMX-BVN-2 demonstrated accuracy for detecting both viral infections and bacterial infections. This shows the potential of host-response tests as a novel and practical approach for determining the causes of infections, which could improve patient outcomes while upholding antimicrobial stewardship.


Assuntos
Infecções Bacterianas/diagnóstico , RNA Mensageiro/análise , Viroses/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Infecções Bacterianas/sangue , Infecções Bacterianas/fisiopatologia , Berlim , Biomarcadores/análise , Biomarcadores/sangue , Serviço Hospitalar de Emergência/organização & administração , Serviço Hospitalar de Emergência/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , RNA Mensageiro/sangue , Curva ROC , Viroses/sangue , Viroses/fisiopatologia
4.
J Mol Med (Berl) ; 99(8): 1023-1031, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34023935

RESUMO

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.


Assuntos
COVID-19/metabolismo , Interações Hospedeiro-Patógeno , SARS-CoV-2/fisiologia , Imunidade Adaptativa , Animais , Antígenos de Grupos Sanguíneos/imunologia , Antígenos de Grupos Sanguíneos/metabolismo , COVID-19/imunologia , COVID-19/terapia , Exocitose , Glicosilação , Humanos , Imunidade Inata , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Internalização do Vírus , Replicação Viral
5.
TH Open ; 5(1): e43-e55, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33564744

RESUMO

COVID-19 (coronavirus disease 2019) patients often show excessive activation of coagulation, associated with increased risk of thrombosis. However, the diagnostic value of coagulation at initial clinical evaluation is not clear. We present an in-depth analysis of coagulation in patients presenting to the emergency department (ED) with suspected COVID-19. N = 58 patients with clinically suspected COVID-19 in the ED were enrolled. N = 17 subsequently tested positive using SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) polymerase chain reaction (PCR) swabs, while in n = 41 COVID-19 was ruled-out. We analyzed both standard and extended coagulation parameters, including thromboplastin time (INR), activated partial thromboplastin time (aPTT), antithrombin, plasminogen, plasminogen activator inhibitor-1 (PAI-1), D-dimers, and fibrinogen at admission, as well as α2-antiplasmin, activated protein C -resistance, factor V, lupus anticoagulant, protein C, protein S, and von Willebrand diagnostics. These data, as well as mortality and further laboratory parameters, were compared across groups based on COVID-19 diagnosis and severity of disease. In patients with COVID-19, we detected frequent clotting abnormalities, including D-dimers. The comparison cohort in the ED, however, showed similarly altered coagulation. Furthermore, parameters previously shown to distinguish between severe and moderate COVID-19 courses, such as platelets, plasminogen, fibrinogen, aPTT, INR, and antithrombin, as well as multiple nonroutine coagulation analytes showed no significant differences between patients with and without COVID-19 when presenting to the ED. At admission to the ED the prevalence of coagulopathy in patients with COVID-19 is high, yet comparable to the non-COVID-19 cohort presenting with respiratory symptoms. Nevertheless, coagulopathy might worsen during disease progression with the need of subsequent risk stratification.

9.
J Psychosom Obstet Gynaecol ; : 1-6, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33252280

RESUMO

OBJECTIVE: The prognosis for ovarian cancer patients remains poor. A key to maximizing survival rates is early detection and treatment. This requires an accurate prediction of malignancy. Our study seeks to improve the accuracy of prediction by focusing on early subjective assessment of malignancy. We therefore investigated the assessment of patients themselves in comparison to the assessment of physicians. METHODS: One thousand three hundred and thirty patients participated in a prospective and multicenter study in six hospitals in Berlin. Using univariate analysis and multivariate logistic regression models, we measured the accuracy of the early subjective assessment in comparison to the final histological outcome. Moreover, we investigated factors related to the assessment of patients and physicians. RESULTS: The patients' assessment of malignancy is remarkably accurate. With a positive predictive value of 58%, the majority of patients correctly assessed a pelvic mass as malignant. With more information available, physicians achieved only a slightly more accurate prediction of 63%. CONCLUSIONS: For the first time, our study considered subjective factors in the diagnostic process of pelvic masses. This paper demonstrates that the patients' personal assessment should be taken seriously as it can provide a significant contribution to earlier diagnosis and thus improved therapy and overall prognosis.

10.
Cell ; 182(6): 1419-1440.e23, 2020 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-32810438

RESUMO

Coronavirus disease 2019 (COVID-19) is a mild to moderate respiratory tract infection, however, a subset of patients progress to severe disease and respiratory failure. The mechanism of protective immunity in mild forms and the pathogenesis of severe COVID-19 associated with increased neutrophil counts and dysregulated immune responses remain unclear. In a dual-center, two-cohort study, we combined single-cell RNA-sequencing and single-cell proteomics of whole-blood and peripheral-blood mononuclear cells to determine changes in immune cell composition and activation in mild versus severe COVID-19 (242 samples from 109 individuals) over time. HLA-DRhiCD11chi inflammatory monocytes with an interferon-stimulated gene signature were elevated in mild COVID-19. Severe COVID-19 was marked by occurrence of neutrophil precursors, as evidence of emergency myelopoiesis, dysfunctional mature neutrophils, and HLA-DRlo monocytes. Our study provides detailed insights into the systemic immune response to SARS-CoV-2 infection and reveals profound alterations in the myeloid cell compartment associated with severe COVID-19.


Assuntos
Infecções por Coronavirus/imunologia , Células Mieloides/imunologia , Mielopoese , Pneumonia Viral/imunologia , Adulto , Idoso , Antígenos CD11/genética , Antígenos CD11/metabolismo , COVID-19 , Células Cultivadas , Infecções por Coronavirus/sangue , Infecções por Coronavirus/patologia , Feminino , Antígenos HLA-DR/genética , Antígenos HLA-DR/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Células Mieloides/citologia , Pandemias , Pneumonia Viral/sangue , Pneumonia Viral/patologia , Proteoma/genética , Proteoma/metabolismo , Proteômica , Análise de Célula Única
11.
Biomarkers ; 25(8): 616-625, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32700561

RESUMO

BACKGROUND: The 2019 coronavirus disease (COVID-19) caused by the SARS-CoV-2 virus has an impact on all aspects of patient care. Serum ferritin generally represents a biomarker of choice when iron deficiency is suspected. However, ferritin is also an acute-phase-protein exhibiting elevated serum concentration in various inflammatory diseases. Here we focus on the role of serum ferritin for diagnostic and clinical management of patients with COVID-19 in comparison with other infectious and non-infectious diseases. METHODS: We examined scientific articles listed in PubMed reporting on ferritin in various infectious and non-infectious diseases. We then compared these results with nine current COVID-19 ferritin reports published in 2020. RESULTS: Several non-infectious, as well as non-COVID-19 infectious diseases, are characterised by a partly dramatic elevation of serum ferritin levels. All COVID-19 studies published between February and May 2020, which documented laboratory serum ferritin, indicate ferritin as a biomarker of COVID-19 severity in hospitalised patients. CONCLUSIONS: Serum ferritin may be considered both a prognostic and stratifying biomarker that can also contribute to therapeutic decision-making concerning patients with COVID-19. It should be emphasised, however, that most scientific reports refer to cohorts in the Asian region. Further validation in other cohorts is urgently required.


Assuntos
Biomarcadores/sangue , COVID-19/sangue , Doenças Transmissíveis/sangue , Ferritinas/sangue , Inflamação/sangue , COVID-19/epidemiologia , COVID-19/virologia , Doenças Transmissíveis/diagnóstico , Feminino , Humanos , Inflamação/diagnóstico , Masculino , Pandemias , Prognóstico , SARS-CoV-2/fisiologia , Sensibilidade e Especificidade
12.
Transfusion ; 60(8): 1828-1836, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32339309

RESUMO

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°C. The BRMs CCL5/RANTES, TGFß1, 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, TGFß1, 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.


Assuntos
Plaquetas/metabolismo , Preservação de Sangue/efeitos adversos , Proteínas Sanguíneas/metabolismo , Temperatura Alta , Agregação Plaquetária , Adulto , Feminino , Humanos , Recém-Nascido , Masculino , Transfusão de Plaquetas/efeitos adversos , Fatores de Tempo , Reação Transfusional/sangue , Reação Transfusional/mortalidade
13.
Clin Chem Lab Med ; 58(5): 709-718, 2020 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-32069224

RESUMO

Background Accurate assessment of kidney function is needed for a variety of clinical indications and for research. The measurement of the serum clearance of iohexol has emerged as a feasible method to reach this objective. We report the analytical validation and clinical application of a new high-performance liquid chromatography (HPLC) - tandem mass spectrometry (MS/MS) assay to quantify iohexol in human serum. Specificity was enhanced due to the use of method specific acceptance limits for relative ion (RI) intensities. Methods The internal standard ioversol was added to 50 µL serum prior to protein precipitation with methanol. Linear gradient elution was performed on a Waters Oasis® HLB column. Three transitions for both iohexol and ioversol were monitored allowing calculation of RIs. Measurements acquired during method validation were used as a training set to establish stricter acceptance criteria for RIs which were then tested retrospectively on clinical routine measurements (86 measurements) and on mathematically simulated interferences. Results The method was linear between 5.0 µg/mL (lower limit of quantification [LLOQ]) and 100.3 µg/mL iohexol. Intraday and interday imprecision were ≤2.6% and ≤3.2%, respectively. Bias was -1.6% to 1.5%. All validation criteria were met, including selectivity, recovery, extraction efficiency and matrix effects. Retrospectively acceptance limits for RIs could be narrowed to ±4 relative standard deviations of the corresponding RIs in the training set. The new limits resulted in an enhanced sensitivity for the simulated interferences. Conclusions Criteria for validation were met and the assay is now used in our clinical routine diagnostics and in research.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Precipitação Química , Cromatografia Líquida de Alta Pressão/normas , Taxa de Filtração Glomerular , Humanos , Iohexol/análise , Iohexol/isolamento & purificação , Iohexol/normas , Testes de Função Renal/métodos , Limite de Detecção , Padrões de Referência , Reprodutibilidade dos Testes , Soro/química , Espectrometria de Massas em Tandem/normas
14.
Haematologica ; 105(8): 2083-2094, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31672904

RESUMO

There is prevailing evidence to suggest a decisive role for platelet-derived growth factors (PDGF) and their receptors in primary myelofibrosis. While PDGF receptor ß (PDGFRß) expression is increased in bone marrow stromal cells of patients correlating with the grade of myelofibrosis, knowledge on the precise role of PDGFRß signaling in myelofibrosis is sparse. Using the Gata-1low mouse model for myelofibrosis, we applied RNA sequencing, protein expression analyses, multispectral imaging and, as a novel approach in bone marrow tissue, an in situ proximity ligation assay to provide a detailed characterization of PDGFRß signaling and regulation during development of myelofibrosis. We observed an increase in PDGFRß and PDGF-B protein expression in overt fibrotic bone marrow, along with an increase in PDGFRß-PDGF-B interaction, analyzed by proximity ligation assay. However, PDGFRß tyrosine phosphorylation levels were not increased. We therefore focused on regulation of PDGFRß by protein tyrosine phosphatases as endogenous PDGFRß antagonists. Gene expression analyses showed distinct expression dynamics among PDGFRß-targeting phosphatases. In particular, we observed enhanced T-cell protein tyrosine phosphatase protein expression and PDGFRß-T-cell protein tyrosine phosphatase interaction in early and overt fibrotic bone marrow of Gata-1low mice. In vitro, T-cell protein tyrosine phosphatase (Ptpn2) knockdown increased PDGFRß phosphorylation at Y751 and Y1021, leading to enhanced downstream signaling in fibroblasts. Furthermore, Ptpn2 knockdown cells showed increased growth rates when exposed to low-serum growth medium. Taken together, PDGF signaling is differentially regulated during myelofibrosis. Protein tyrosine phosphatases, which have so far not been examined during disease progression, are novel and hitherto unrecognized components in myelofibrosis.


Assuntos
Mielofibrose Primária , Animais , Camundongos , Fosforilação , Fator de Crescimento Derivado de Plaquetas/genética , Fator de Crescimento Derivado de Plaquetas/metabolismo , Mielofibrose Primária/genética , Receptor beta de Fator de Crescimento Derivado de Plaquetas/genética , Transdução de Sinais
15.
Clin Chem Lab Med ; 58(2): 213-221, 2020 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-31665108

RESUMO

Background Lactate dehydrogenase (LD) activity is routinely monitored for therapeutic risk stratification of malignant diseases, but is also prone to preanalytical influences. Methods We systematically analyzed the impact of defined preanalytical conditions on the hemolysis-susceptible parameters LD, potassium (K) and hemolysis index in vacuum blood collection tubes (serum [SE], heparin plasma [HP]). Blood was collected by venipuncture from healthy volunteers. Tubes were either filled or underfilled to approximately 50%, then processed directly or stored at room temperature for 4 h. Potassium (K), sodium (Na), chloride (Cl), LD, creatine kinase (CK), total cholesterol, and indices for hemolysis, icterus, and lipemia were analyzed. Filling velocity was determined in a subset of tubes. Findings in healthy volunteers were reconfirmed in an in-patient cohort (n = 74,751) that was analyzed for plasma yield and LD data distribution. Results LD activity was higher in HP compared to SE. Underfilling led to higher LD values (SE: +21.6%; HP: +28.3%), K (SE: +4.2%; HP: +5.3%), and hemolysis index (SE: +260.8%; HP: +210.0%), while other analytes remained largely unchanged. Filling velocity of tubes was approximately 3-fold higher in the first half compared to the second half in both HP and SE collection tubes. Importantly, plasma yield also inversely correlated with LD in routine patients. By calculating reference limits, the lowest plasma yield quartile of the patient cohort displayed LD values clearly exceeding current reference recommendations. Conclusions Underfilling of tubes leads to a higher proportion of blood aspirated with high velocity and relevant elevations in LD. This finding should be considered in cases of clinically implausible elevated LD activities.


Assuntos
Heparina/química , L-Lactato Desidrogenase/sangue , Flebotomia/métodos , Adulto , Feminino , Hemólise , Humanos , L-Lactato Desidrogenase/normas , Masculino , Pessoa de Meia-Idade , Flebotomia/instrumentação , Flebotomia/normas , Potássio/sangue , Fase Pré-Analítica , Sódio/sangue
16.
Radiology ; 292(3): 664-672, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31264950

RESUMO

Background In the absence of randomized studies, it has been controversial whether the likelihood of acute kidney injury (AKI) differs between intravenous and intra-arterial contrast agent administration. Purpose To compare intravenous versus intra-arterial contrast agent administration in relationship to AKI and analyze the association between AKI and chronic kidney disease (defined as at least mildly decreased estimated glomerular filtration rates [eGFRs]). Materials and Methods This was a prospective study (ClinicalTrials.gov: NCT00844220) that involved randomizing participants with atypical chest pain and suspected coronary artery disease (CAD) between February 2009 and August 2015 to undergo coronary CT angiography with intravenous contrast agent administration or cardiac catheterization angiography with intra-arterial contrast agent administration. This prespecified secondary analysis compared AKI (serum creatinine increase of ≥ 25% or 0.5 mg/dL after 18-24 or 46-50 hours) determined by blinded investigators using absolute differences and relative risks, including two-sided 95% confidence intervals (CIs). Results A total of 320 participants (163 [50.9%] women; mean age, 60 years ± 11) were included. Baseline eGFR did not differ between the CT angiography group (84.3 mL/min/1.73 m2 ± 17.2) and the catheterization group (87.1 mL/min/1.73 m2 ± 16.7) (P = .14). AKI occurred in nine of 161 participants in the CT angiography group (5.6%; 95% CI: 3%, 10%) and in 21 of 159 participants in the catheterization group (13.2%; 95% CI: 9%,19%) (relative risk, 2.4; 95% CI: 1.1, 5.0; P = .02). Also in the subgroup of participants without obstructive CAD, in those not requiring coronary interventions, AKI was more common in the catheterization group (11.9%; 95% CI: 8%, 19%) than in the CT angiography group (4.3% [95% CI: 2%, 9%]; difference, 7.7% [95% CI: 1.3%, 14.1%]; relative risk, 2.8 [95% CI: 1.1, 7.0]; P = .02). Obstructive CAD (odds ratio [OR]: 2.7 [95% CI: 1.1, 6.6]; P = .02), femoral catheter access (OR: 2.5 [95% CI: 1.1, 5.6]; P = .04), and cine ventriculography were associated with AKI (OR: 2.3 [95% CI: 1.0, 4.9]; P = .03). In multivariable analysis, the presence of postcontrast AKI was associated with chronic kidney disease (hazard ratio: 12.4 [95% CI: 4.5, 34.6]; P < .01). Conclusion Acute kidney injury was more common after cardiac catheterization than after CT angiography in this prospective randomized study of patients suspected of having coronary artery disease. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Einstein and Newhouse in this issue.


Assuntos
Injúria Renal Aguda/epidemiologia , Meios de Contraste/administração & dosagem , Meios de Contraste/efeitos adversos , Doença da Artéria Coronariana/epidemiologia , Administração Intravenosa , Cateterismo Cardíaco/efeitos adversos , Causalidade , Comorbidade , Angiografia por Tomografia Computadorizada/efeitos adversos , Feminino , Alemanha , Taxa de Filtração Glomerular , Humanos , Injeções Intra-Arteriais , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Insuficiência Renal Crônica/epidemiologia , Fatores de Risco
17.
PLoS One ; 13(7): e0200507, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29995966

RESUMO

Glycome modulations have been described in the onset and progression of many diseases. Thus, many studies have proposed glycans from blood glycoproteins as disease markers. Astonishingly, little effort has been given unraveling preanalytical conditions potentially influencing glycan analysis prior to blood biomarker studies. In this work, we evaluate for the first time the effect of hemolysis, storage and blood collection, but also influence of various times and temperatures between individual processing steps on the total N-glycome and on a glycan-biomarker score. Venous blood was collected from 10 healthy donors in 11 blood collection tubes with different additives, processed variously to obtain 16 preanalytical variables and N-glycans released from serum or plasma were analyzed by MALDI-TOF-MS and capillary electrophoresis coupled with fluorescence detection (CE-LIF) for the first time. Long time storage of deep frozen samples at -20°C or -80°C exerted only a minor influence on the glycome as demonstrated by CE-LIF. The N-glycome was very stable evidenced by MALDI-TOF when stored at 4°C for at least 48 hours and blood collected in tubes devoid of additives. The glycome was stable upon storage after centrifugation and aliquoting, which is an important information considering future diagnostic applications. Hemolysis, however, negatively correlated with an established glycan score for ovarian cancer, when evaluated by MALDI-TOF-MS measurement by affecting relative intensities of certain glycans, which could lead to false negative / positive results in glycan biomarker studies.


Assuntos
Biomarcadores Tumorais/sangue , Carboidratos/sangue , Neoplasias Ovarianas/sangue , Manejo de Espécimes/métodos , Adulto , Eletroforese Capilar , Feminino , Humanos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
18.
Chembiochem ; 18(13): 1141-1145, 2017 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-28621497

RESUMO

A creative pioneer: Werner Reutter (1937-2016) was a scientist who both made fundamental discoveries in glycobiology and reached out to disciplines beyond his core field. Many of his former colleagues and students will remember his desire to exchange research ideas, which ultimately contributed to the birth of new research fields.


Assuntos
Glicômica , Biologia Molecular , Metabolismo dos Carboidratos/genética , Glicômica/história , Glicômica/métodos , História do Século XX , História do Século XXI , Humanos , Engenharia Metabólica/história , Engenharia Metabólica/métodos , Biologia Molecular/história , Biologia Molecular/métodos , Ácidos Siálicos/genética , Ácidos Siálicos/metabolismo , Recursos Humanos
19.
Chembiochem ; 18(13): 1338-1345, 2017 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-28489325

RESUMO

L-Selectin, a cell-adhesion receptor on the surface of most leukocytes, contains seven N-glycosylation sites. In order to obtain the crystal structure of human L-selectin, we expressed a shortened version of L-selectin comprising the C-type lectin and EGF-like domains (termed LE) and systematically analysed mutations of the three glycosylation sites (Asn22, Asn66 and Asn139) in order to reduce macroheterogeneity. After we further removed microheterogeneity, we obtained crystals that diffracted X-rays up to 1.9 Šfrom a variant (LE010) with exchanges N22Q and N139Q and one GlcNAc2 Man5 N-glycan chain attached to Asn66. Crystal-structure analysis showed that the terminal mannose of GlcNAc2 Man5 of one LE010 molecule was coordinated to Ca2+ in the binding site of a symmetry-related LE010. The orientation of the lectin and EGF-like domain was similar to the described "bent" conformation of E- and P-selectins. The Ca2+ -binding site reflects the binding mode seen in E- and P-selectin structures co-crystallised with ligands.


Assuntos
Cálcio/química , Fator de Crescimento Epidérmico/química , Selectina L/química , Lectinas Tipo C/química , Polissacarídeos/química , Sítios de Ligação , Cálcio/metabolismo , Clonagem Molecular , Cristalografia por Raios X , Fator de Crescimento Epidérmico/genética , Fator de Crescimento Epidérmico/metabolismo , Expressão Gênica , Glicosilação , Células HEK293 , Humanos , Selectina L/genética , Selectina L/metabolismo , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Modelos Moleculares , Mutação , Polissacarídeos/metabolismo , Ligação Proteica , Domínios Proteicos , Domínios e Motivos de Interação entre Proteínas , Estrutura Secundária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
20.
Chembiochem ; 18(13): 1234-1241, 2017 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-28370937

RESUMO

Human embryonic stem cells (hESCs) are pluripotent stem cells that offer a wide range of applications in regenerative medicine. In addition, they have been proposed as an appropriate alternative source of hepatocytes. In this work, hESCs were differentiated into definitive endodermal cells (DECs), followed by maturation into hepatocyte-like cells (HLCs). Their cell-surface N-glycome was profiled and also compared with that of primary human hepatocytes (PHHs). Undifferentiated hESCs contained large amounts of high-mannose N-glycans. In contrast, complex-type N-glycans such as asialylated or monosialylated biantennary and triantennary N-glycans were dominant in HLCs, and fully galactosylated structures were significantly more abundant than in undifferentiated hESCs. The cell-surface N-glycosylation of PHHs was more biologically processed than that of HLCs, with bisialylated biantennary and trisialylated triantennary structures predominant. This is the first report of the cell surface N-glycome of PHHs and of HLCs being directly generated from hESCs without embryoid body formation.


Assuntos
Membrana Celular/química , Glicômica , Hepatócitos/química , Células-Tronco Embrionárias Humanas/química , Polissacarídeos/química , Biomarcadores/metabolismo , Configuração de Carboidratos , Sequência de Carboidratos , Diferenciação Celular , Membrana Celular/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Metabolismo Energético , Expressão Gênica , Glicosilação , Hepatócitos/citologia , Hepatócitos/metabolismo , Células-Tronco Embrionárias Humanas/citologia , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , Manose/química , Manose/metabolismo , Polissacarídeos/metabolismo , Cultura Primária de Células , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
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