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1.
J Chem Phys ; 161(5)2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39087537

RESUMO

The diffusion of cations in organic solvent solutions is important for the performance of metal-ion batteries. In this article, pulsed field gradient nuclear magnetic resonance experiments and fully atomistic molecular dynamic simulations were employed to study the temperature-dependent diffusive behavior of various liquid electrolytes representing 1M propylene carbonate solutions of metal salts with bis(trifluoromethylsulfonyl)imide (TFSI-) or hexafluorophosphate (PF6-) anions commonly used in lithium-ion batteries and beyond. The experimental studies revealed the temperature dependence of the diffusion coefficients for the propylene carbonate (PC) solvent and for the anions following an Arrhenius type of behavior. It was observed that the PC molecules are the faster species. For the monovalent cations (Li+, Na+, K+), the PC solvent diffusion was enhanced as the cation size increased, while for the divalent cations (Mg2+, Ca2+, Sr2+, Ba2+), the opposite trend was observed, i.e., the diffusion coefficients decreased as the cation size increased. The anion diffusion in LiTFSI and NaTFSI solutions was found to be similar, while in electrolytes with divalent cations, a decrease in anion diffusion with increasing cation size was observed. It was shown that non-polarizable charge-scaled force fields could correspond perfectly to the experimental values of the anion and PC solvent diffusion coefficients in salt solutions of both monovalent (Li+, Na+, K+) and divalent (Mg2+, Ca2+, Sr2+, Ba2+) cations at a range of operational temperatures. Finally, after calculating the radial distribution functions between cations, anions, and solvent molecules, the increase in the PC diffusion coefficient established with the increase in cation size for monovalent cations was clearly explained by the large hydration shell of small Li+ cations, due to their strong interaction with the PC solvent. In solutions with larger monovalent cations, such as Na+, and with a smaller solvation shell of PC, the PC diffusion is faster due to more liberated solvent molecules. In the salt solutions with divalent cations, both the anion and the PC diffusion coefficients decreased as the cation size increased due to an enhanced cation-anion coordination, which was accompanied by an increase in the amount of PC in the cation solvation shell due to the presence of anions.

2.
Eur J Immunol ; 49(7): 1117-1126, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31002172

RESUMO

The first-in-human clinical trial of the CD28-specific monoclonal antibody (mAb) TGN1412 resulted in a life-threatening cytokine release syndrome. Although TGN1412 was designed as IgG4, known for weak Fc:Fcγ receptor (FcγR) interactions, these interactions contributed to TGN1412-induced T-cell activation. Using cell lines (TFs) expressing human FcγRI, -IIa, -IIb, or -III, we show that TGN1412 and TGN1412 as IgG1 and IgG2 are bound by FcγRs as it can be deduced from literature. However, upon coculture of TGN1412-decorated T cells with TFs or human primary blood cells, we observed that binding capacities by FcγRs do not correlate with the strength of the mediated effector function. FcγRIIa and FcγRIIb, showing no or very minor binding to TGN1412, mediated strongest T cell proliferation, while high-affinity FcγRI, exhibiting strong TGN1412 binding, mediated hardly any T-cell proliferation. These findings are of biological relevance because we show that FcγRI binds TGN1412, thus prevents binding to FcγRIIa or FcγRIIb, and consequently disables T-cell proliferation. In line with this, FcγRI- FcγRII+ but not FcγRI+ FcγRII+ monocytes mediate TGN1412-induced T-cell proliferation. Collectively, by using TGN1412 as example, our results indicate that binding of monomeric IgG subclasses does not predict the FcγR-mediated effector function, which has major implications for the design of therapeutic mAbs.


Assuntos
Anticorpos Monoclonais Humanizados/metabolismo , Síndrome da Liberação de Citocina/imunologia , Imunoglobulina G/metabolismo , Imunoterapia/efeitos adversos , Monócitos/imunologia , Receptores de IgG/metabolismo , Linfócitos T/imunologia , Animais , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/uso terapêutico , Antígenos CD28/antagonistas & inibidores , Linhagem Celular , Proliferação de Células , Síndrome da Liberação de Citocina/etiologia , Humanos , Ativação Linfocitária , Camundongos , Ligação Proteica , Receptores de IgG/genética
3.
BMC Med Inform Decis Mak ; 20(1): 28, 2020 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-32041606

RESUMO

BACKGROUND: Individualization and patient-specific optimization of treatment is a major goal of modern health care. One way to achieve this goal is the application of high-resolution diagnostics together with the application of targeted therapies. However, the rising number of different treatment modalities also induces new challenges: Whereas randomized clinical trials focus on proving average treatment effects in specific groups of patients, direct conclusions at the individual patient level are problematic. Thus, the identification of the best patient-specific treatment options remains an open question. Systems medicine, specifically mechanistic mathematical models, can substantially support individual treatment optimization. In addition to providing a better general understanding of disease mechanisms and treatment effects, these models allow for an identification of patient-specific parameterizations and, therefore, provide individualized predictions for the effect of different treatment modalities. RESULTS: In the following we describe a software framework that facilitates the integration of mathematical models and computer simulations into routine clinical processes to support decision-making. This is achieved by combining standard data management and data exploration tools, with the generation and visualization of mathematical model predictions for treatment options at an individual patient level. CONCLUSIONS: By integrating model results in an audit trail compatible manner into established clinical workflows, our framework has the potential to foster the use of systems-medical approaches in clinical practice. We illustrate the framework application by two use cases from the field of haematological oncology.


Assuntos
Tomada de Decisão Clínica/métodos , Simulação por Computador , Sistemas de Apoio a Decisões Clínicas , Doenças Hematológicas , Modelos Teóricos , Software , Fluxo de Trabalho , Humanos , Estudo de Prova de Conceito
4.
Stud Health Technol Inform ; 316: 1472-1476, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39176482

RESUMO

This study advances the utility of synthetic study data in hematology, particularly for Acute Myeloid Leukemia (AML), by facilitating its integration into healthcare systems and research platforms through standardization into the Observational Medical Outcomes Partnership (OMOP) and Fast Healthcare Interoperability Resources (FHIR) formats. In our previous work, we addressed the need for high-quality patient data and used CTAB-GAN+ and Normalizing Flow (NFlow) to synthesize data from 1606 patients across four multicenter AML clinical trials. We published the generated synthetic cohorts, that accurately replicate the distributions of key demographic, laboratory, molecular, and cytogenetic variables, alongside patient outcomes, demonstrating high fidelity and usability. The conversion to the OMOP format opens avenues for comparative observational multi-center research by enabling seamless combination with related OMOP datasets, thereby broadening the scope of AML research. Similarly, standardization into FHIR facilitates further developments of applications, e.g. via the SMART-on-FHIR platform, offering realistic test data. This effort aims to foster a more collaborative research environment and facilitate the development of innovative tools and applications in AML care and research.


Assuntos
Leucemia Mieloide Aguda , Humanos , Hematologia , Interoperabilidade da Informação em Saúde , Registros Eletrônicos de Saúde , Avaliação de Resultados em Cuidados de Saúde
5.
Stud Health Technol Inform ; 316: 643-644, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39176823

RESUMO

The integration of artificial intelligence (AI) algorithms into clinical practice holds immense potential to improve patient care, but widespread adoption still faces significant challenges, including interoperability issues. We propose a concept for the agile development of an IT platform to integrate AI-based applications into clinical workflows for a use case in ophthalmology.


Assuntos
Inteligência Artificial , Integração de Sistemas , Oftalmologia , Sistemas de Apoio a Decisões Clínicas/organização & administração , Humanos , Registros Eletrônicos de Saúde , Algoritmos , Fluxo de Trabalho
6.
Stud Health Technol Inform ; 317: 139-145, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39234716

RESUMO

INTRODUCTION: Seamless interoperability of ophthalmic clinical data is beneficial for improving patient care and advancing research through the integration of data from various sources. Such consolidation increases the amount of data available, leading to more robust statistical analyses, and improving the accuracy and reliability of artificial intelligence models. However, the lack of consistent, harmonized data formats and meanings (syntactic and semantic interoperability) poses a significant challenge in sharing ophthalmic data. METHODS: The Health Level 7 (HL7) Fast Healthcare Interoperability Resources (FHIR), a standard for the exchange of healthcare data, emerges as a promising solution. To facilitate cross-site data exchange in research, the German Medical Informatics Initiative (MII) has developed a core data set (CDS) based on FHIR. RESULTS: This work investigates the suitability of the MII CDS specifications for exchanging ophthalmic clinical data necessary to train and validate a specific machine learning model designed for predicting visual acuity. In interdisciplinary collaborations, we identified and categorized the required ophthalmic clinical data and explored the possibility of its mapping to FHIR using the MII CDS specifications. DISCUSSION: We found that the current FHIR MII CDS specifications do not completely accommodate the ophthalmic clinical data we investigated, indicating that the creation of an extension module is essential.


Assuntos
Interoperabilidade da Informação em Saúde , Humanos , Interoperabilidade da Informação em Saúde/normas , Registros Eletrônicos de Saúde/normas , Alemanha , Aprendizado de Máquina , Nível Sete de Saúde/normas , Oftalmopatias/terapia , Oftalmologia
7.
Front Med (Lausanne) ; 11: 1377209, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38903818

RESUMO

Introduction: Obtaining real-world data from routine clinical care is of growing interest for scientific research and personalized medicine. Despite the abundance of medical data across various facilities - including hospitals, outpatient clinics, and physician practices - the intersectoral exchange of information remains largely hindered due to differences in data structure, content, and adherence to data protection regulations. In response to this challenge, the Medical Informatics Initiative (MII) was launched in Germany, focusing initially on university hospitals to foster the exchange and utilization of real-world data through the development of standardized methods and tools, including the creation of a common core dataset. Our aim, as part of the Medical Informatics Research Hub in Saxony (MiHUBx), is to extend the MII concepts to non-university healthcare providers in a more seamless manner to enable the exchange of real-world data among intersectoral medical sites. Methods: We investigated what services are needed to facilitate the provision of harmonized real-world data for cross-site research. On this basis, we designed a Service Platform Prototype that hosts services for data harmonization, adhering to the globally recognized Health Level 7 (HL7) Fast Healthcare Interoperability Resources (FHIR) international standard communication format and the Observational Medical Outcomes Partnership (OMOP) common data model (CDM). Leveraging these standards, we implemented additional services facilitating data utilization, exchange and analysis. Throughout the development phase, we collaborated with an interdisciplinary team of experts from the fields of system administration, software engineering and technology acceptance to ensure that the solution is sustainable and reusable in the long term. Results: We have developed the pre-built packages "ResearchData-to-FHIR," "FHIR-to-OMOP," and "Addons," which provide the services for data harmonization and provision of project-related real-world data in both the FHIR MII Core dataset format (CDS) and the OMOP CDM format as well as utilization and a Service Platform Prototype to streamline data management and use. Conclusion: Our development shows a possible approach to extend the MII concepts to non-university healthcare providers to enable cross-site research on real-world data. Our Service Platform Prototype can thus pave the way for intersectoral data sharing, federated analysis, and provision of SMART-on-FHIR applications to support clinical decision making.

8.
Stud Health Technol Inform ; 317: 67-74, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39234708

RESUMO

INTRODUCTION: The Medical Informatics Initiative (MII) in Germany has pioneered platforms such as the National Portal for Medical Research Data (FDPG) to enhance the accessibility of data from clinical routine care for research across both university and non-university healthcare settings. This study explores the efficacy of the Medical Informatics Hub in Saxony (MiHUBx) services by integrating Klinikum Chemnitz gGmbH (KC) with the FDPG, leveraging the Fast Healthcare Interoperability Resources Core Data Set of the MII to standardize and harmonize data from disparate source systems. METHODS: The employed procedures include deploying installation packages to convert data into FHIR format and utilizing the Research Data Repository for structured data storage and exchange within the clinical infrastructure of KC. RESULT: Our results demonstrate successful integration, the development of a comprehensive deployment diagram, additionally, it was demonstrated that the non-university site can report clinical data to the FDPG. DISCUSSION: The discussion reflects on the practical application of this integration, highlighting its potential scalability to even smaller healthcare facilities and to pave the way to access to more medical data for research. This exemplary demonstration of the interplay of different tools provides valuable insights into technical and operational challenges, setting a precedent for future expansions and contributing to the democratization of medical data access.


Assuntos
Registros Eletrônicos de Saúde , Alemanha , Humanos , Informática Médica , Armazenamento e Recuperação da Informação/métodos , Integração de Sistemas , Interoperabilidade da Informação em Saúde
9.
bioRxiv ; 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38464092

RESUMO

Human cytomegalovirus (HCMV) encodes four viral Fc-gamma receptors (vFcγRs) that counteract antibody-mediated activation in vitro , but their role in infection and pathogenesis is unknown. To examine the in vivo function of vFcγRs in animal hosts closely related to humans, we identified and characterized vFcγRs encoded by rhesus CMV (RhCMV). We demonstrate that Rh05, Rh152/151 and Rh173 represent the complete set of RhCMV vFcγRs, each displaying functional similarities to their respective HCMV orthologs with respect to antagonizing host FcγR activation in vitro . When RhCMV-naïve rhesus macaques were infected with vFcγR-deleted RhCMV, peak plasma viremia levels and anti-RhCMV antibody responses were comparable to wildtype infections. However, the duration of plasma viremia was significantly shortened in immunocompetent, but not in CD4+ T cell-depleted animals. Since vFcγRs were not required for superinfection, we conclude that vFcγRs delay control by virus-specific adaptive immune responses, particularly antibodies, during primary infection.

10.
Cell Rep Med ; 5(4): 101483, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38579727

RESUMO

Immune cell phenotyping frequently detects lineage-unrelated receptors. Here, we report that surface receptors can be transferred from primary macrophages to CD4 T cells and identify the Fcγ receptor CD32 as driver and cargo of this trogocytotic transfer. Filamentous CD32+ nanoprotrusions deposit distinct plasma membrane patches onto target T cells. Transferred receptors confer cell migration and adhesion properties, and macrophage-derived membrane patches render resting CD4 T cells susceptible to infection by serving as hotspots for HIV-1 binding. Antibodies that recognize T cell epitopes enhance CD32-mediated trogocytosis. Such autoreactive anti-HIV-1 envelope antibodies can be found in the blood of HIV-1 patients and, consistently, the percentage of CD32+ CD4 T cells is increased in their blood. This CD32-mediated, antigen-independent cell communication mode transiently expands the receptor repertoire and functionality of immune cells. HIV-1 hijacks this mechanism by triggering the generation of trogocytosis-promoting autoantibodies to gain access to immune cells critical to its persistence.


Assuntos
Infecções por HIV , Soropositividade para HIV , HIV-1 , Humanos , Linfócitos T CD4-Positivos , Receptores de IgG/metabolismo , Autoanticorpos/metabolismo , Trogocitose
11.
PLOS Digit Health ; 2(5): e0000140, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37186586

RESUMO

The transfer of new insights from basic or clinical research into clinical routine is usually a lengthy and time-consuming process. Conversely, there are still many barriers to directly provide and use routine data in the context of basic and clinical research. In particular, no coherent software solution is available that allows a convenient and immediate bidirectional transfer of data between concrete treatment contexts and research settings. Here, we present a generic framework that integrates health data (e.g., clinical, molecular) and computational analytics (e.g., model predictions, statistical evaluations, visualizations) into a clinical software solution which simultaneously supports both patient-specific healthcare decisions and research efforts, while also adhering to the requirements for data protection and data quality. Specifically, our work is based on a recently established generic data management concept, for which we designed and implemented a web-based software framework that integrates data analysis, visualization as well as computer simulation and model prediction with audit trail functionality and a regulation-compliant pseudonymization service. Within the front-end application, we established two tailored views: a clinical (i.e., treatment context) perspective focusing on patient-specific data visualization, analysis and outcome prediction and a research perspective focusing on the exploration of pseudonymized data. We illustrate the application of our generic framework by two use-cases from the field of haematology/oncology. Our implementation demonstrates the feasibility of an integrated generation and backward propagation of data analysis results and model predictions at an individual patient level into clinical decision-making processes while enabling seamless integration into a clinical information system or an electronic health record.

12.
NPJ Vaccines ; 8(1): 8, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36737485

RESUMO

Human cytomegalovirus (HCMV) frequently causes congenital infections, resulting in birth defects and developmental disorders. A vaccine is needed, but unavailable. We analyzed the potential of CMV mutants, lacking their STAT2 antagonists to serve as live attenuated vaccine viruses in mice. Infections with attenuated viruses elicited strong ELISA-reactive binding IgG responses and induced neutralizing antibodies as well as antibodies stimulating cellular Fcγ receptors, including the antibody-dependent cellular cytotoxicity (ADCC)-eliciting receptors FcγRIII/CD16 and FcγRIV. Accordingly, vaccinated mice were fully protected against challenge infections. Female mice vaccinated prior to gestation transmitted CMV-specific IgG to their offspring, which protected the progeny from perinatal infections in a mouse model for congenital CMV disease. To define the role of maternal antibodies, female mice either capable or incapable of producing antibodies were vaccinated and subsequently bred to males of the opposite genotype. Challenge infections of the genotypically identical F1 generation revealed the indispensability of maternal antibodies for vaccine-induced protection against cytomegaloviruses.

13.
Elife ; 102021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-33724188

RESUMO

Human cytomegalovirus (HCMV) is endowed with multiple highly sophisticated immune evasion strategies. This includes the evasion from antibody mediated immune control by counteracting host Fc-gamma receptor (FcγR) mediated immune control mechanisms such as antibody-dependent cellular cytotoxicity (ADCC). We have previously shown that HCMV avoids FcγR activation by concomitant expression of the viral Fc-gamma-binding glycoproteins (vFcγRs) gp34 and gp68. We now show that gp34 and gp68 bind IgG simultaneously at topologically different Fcγ sites and achieve efficient antagonization of host FcγR activation by distinct but synergizing mechanisms. While gp34 enhances immune complex internalization, gp68 acts as inhibitor of host FcγR binding to immune complexes. In doing so, gp68 induces Fcγ accessibility to gp34 and simultaneously limits host FcγR recognition. The synergy of gp34 and gp68 is compelled by the interfering influence of excessive non-immune IgG ligands and highlights conformational changes within the IgG globular chains critical for antibody effector function.


Human cytomegalovirus is a type of herpes virus that rarely causes symptoms in healthy people but can cause serious complications in unborn babies and in people with compromised immune systems, such as transplant recipients. The virus has found ways to successfully evade the immune system, and once infected, the body retains the virus for life. It deploys an arsenal of proteins that bind to antibodies, specialized proteins the immune system uses to flag virus-infected cells for destruction. This prevents certain cells of the immune system, the natural killer cells, from recognizing and destroying virus-infected cells. These immune-evading proteins are called viral Fc-gamma receptors, or vFcγRs. While it has been previously shown that these receptors are able to evade the immune system, it remained unknown how exactly they prevent natural killer cells from recognizing infected cells. Now, Kolb et al. show that the cytomegalovirus deploys two vFcγRs called gp34 and gp68, which work together to block natural killer cells. The latter reduces the ability of natural killer cells to bind to antibodies on cytomegalovirus-infected cells. This paves the way for gp34 to pull virus proteins from the surface of the infected cell, making them inaccessible to the immune system. Neither protein fully protects virus-infected cells on its own, but together they are highly effective. The experiments reveal further details about how cytomegalovirus uses two defense mechanisms simultaneously to outmaneuver the immune system. Understanding this two-part viral evasion system may help scientists to develop vaccines or new treatments that can protect vulnerable people from diseases caused by the cytomegalovirus.


Assuntos
Citomegalovirus/imunologia , Imunoglobulina G/metabolismo , Receptores de IgG/antagonistas & inibidores , Citotoxicidade Celular Dependente de Anticorpos , Proteínas de Transporte/metabolismo , Linhagem Celular , Citomegalovirus/metabolismo , Glicoproteínas/metabolismo , Humanos , Evasão da Resposta Imune , Células Matadoras Naturais/metabolismo , Glicoproteínas de Membrana/metabolismo , Ligação Proteica , Receptores de IgG/imunologia , Receptores de IgG/metabolismo , Proteínas Virais/metabolismo
14.
Front Microbiol ; 11: 601555, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33281801

RESUMO

Viral infections are a global disease burden with only a limited number of antiviral agents available. Due to newly emerging viral pathogens and increasing occurrence of drug resistance, there is a continuous need for additional therapeutic options, preferably with extended target range. In the present study, we describe a novel antiviral peptide with broad activity against several double-stranded DNA viruses. The 22-mer peptide TAT-I24 potently neutralized viruses such as herpes simplex viruses, adenovirus type 5, cytomegalovirus, vaccinia virus, and simian virus 40 in cell culture models, while being less active against RNA viruses. The peptide TAT-I24 therefore represents a novel and promising drug candidate for use against double-stranded DNA viruses.

15.
BJU Int ; 103(8): 1040-6, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18990139

RESUMO

OBJECTIVE: To describe the lymphatic vessel density and to determine the functional and prognostic significance of tumoral lymphatic vessels in upper tract urothelial carcinoma (UTUC). PATIENTS AND METHODS: The study included 65 patients who had a radical nephroureterectomy (RNU) for UTUC between 1997 and 2004. All pathological slides were re-evaluated by one reference pathologist and clinical data were reviewed. Lymphatic endothelial cells (LECs) were stained immunohistochemically using D2-40. The lymphatic vessel density (LVD) was described in representative intratumoral (ITLVD), peritumoral (PTLVD) and non-tumoral (NTLVD) areas. Random samples were selected for double-immunostaining with D2-40 and CD-34 (to distinguish blood and lymphatic vessels) and the proliferation marker Ki-67 to detect lymphangiogenesis. The primary outcome measures were disease-specific survival (DSS) and disease recurrence (urothelial and/or distant). RESULTS: The median (interquartile range) PTLVD was 4.0 (3.0-6.3), and significantly higher than that for ITLVD, of 0.3 (0-1.7) (P < 0.001), and NTLVD, of 3 (2.0-3.7) (P < 0.001). Both a higher ITLVD and PTLVD, the presence of lymphovascular invasion (LVI) (each P < 0.001) and a high tumour grade (P = 0.004) were associated with reduced DSS on univariate analysis. A higher PTLVD (P = 0.028) and the presence of LVI (P = 0.020) independently predicted reduced DSS on multivariate analysis. IT and PT lymphatic vessels showed proliferating LECs in all analysed samples. CONCLUSION: Lymphangiogenesis is present in UTUC, as shown by a significantly increased PTLVD and proliferating LECs. Our findings suggest functional relevance of PT lymphatic vessels during lymphatic tumour spread. PTLVD is a potential novel prognostic factor for DSS in UTUC, and further prospective studies will be needed to determine the effect of its routine evaluation on clinical outcomes of this malignancy.


Assuntos
Carcinoma de Células de Transição/patologia , Linfangiogênese , Vasos Linfáticos/patologia , Nefrectomia/métodos , Neoplasias Urológicas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células de Transição/cirurgia , Feminino , Humanos , Imuno-Histoquímica , Metástase Linfática , Masculino , Glicoproteínas de Membrana/metabolismo , Pessoa de Meia-Idade , Análise Multivariada , Estadiamento de Neoplasias , Prognóstico , Resultado do Tratamento , Neoplasias Urológicas/cirurgia
16.
Front Immunol ; 10: 2920, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31921179

RESUMO

Lower respiratory tract infections, such as infections caused by influenza A viruses, are a constant threat for public health. Antivirals are indispensable to control disease caused by epidemic as well as pandemic influenza A. We developed a novel anti-influenza A virus approach based on an engineered single-domain antibody (VHH) construct that can selectively recruit innate immune cells to the sites of virus replication. This protective construct comprises two VHHs. One VHH binds with nanomolar affinity to the conserved influenza A matrix protein 2 (M2) ectodomain (M2e). Co-crystal structure analysis revealed that the complementarity determining regions 2 and 3 of this VHH embrace M2e. The second selected VHH specifically binds to the mouse Fcγ Receptor IV (FcγRIV) and was genetically fused to the M2e-specific VHH, which resulted in a bi-specific VHH-based construct that could be efficiently expressed in Pichia pastoris. In the presence of M2 expressing or influenza A virus-infected target cells, this single domain antibody construct selectively activated the mouse FcγRIV. Moreover, intranasal delivery of this bispecific FcγRIV-engaging VHH construct protected wild type but not FcγRIV-/- mice against challenge with an H3N2 influenza virus. These results provide proof of concept that VHHs directed against a surface exposed viral antigen can be readily armed with effector functions that trigger protective antiviral activity beyond direct virus neutralization.


Assuntos
Anticorpos Antivirais/imunologia , Vírus da Influenza A/imunologia , Influenza Humana/imunologia , Influenza Humana/metabolismo , Influenza Humana/virologia , Receptores de IgG/metabolismo , Anticorpos de Domínio Único/imunologia , Proteínas da Matriz Viral/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Biespecíficos/química , Anticorpos Biespecíficos/imunologia , Anticorpos Antivirais/química , Linhagem Celular , Humanos , Camundongos , Modelos Moleculares , Peptídeos/química , Peptídeos/imunologia , Conformação Proteica , Receptores de IgG/química , Anticorpos de Domínio Único/química , Relação Estrutura-Atividade , Proteínas da Matriz Viral/química
17.
Front Psychol ; 9: 1087, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30026712

RESUMO

Procrastination is a form of self-regulation failure characterized by the irrational delay of tasks despite potentially negative consequences. Previous research on procrastination was mainly conducted in academic settings, oftentimes combined with a focus on individual differences. As a consequence, scholarly knowledge about how situational factors affect procrastination in work settings is still scarce. Drawing on job stress literature, we assumed that work characteristics go along with cognitive appraisals of the work situation as a challenge and/or hindrance, that these cognitive appraisals affect employees' self-regulation effort to overcome inner resistances, and that self-regulation effort should in turn be related to workplace procrastination. In our study, we focused on three specific work characteristics that we expected to trigger both challenge and hindrance appraisal simultaneously: time pressure, problem solving, and planning and decision-making. We hypothesized serial indirect effects of these work characteristics on workplace procrastination via cognitive appraisal and self-regulation processes that unfold within individuals over short periods of time. Consequently, we conducted a diary study with three measurement occasions per workday over a period of 12 days. Overall, 762 day-level datasets from 110 employees were included in Bayesian multilevel structural equation modeling (MSEM; controlled for sleep quality and occupational self-efficacy). Our results revealed negative serial indirect effects of all three work characteristics on workplace procrastination via increased challenge appraisal and subsequently reduced self-regulation effort. Further, our results showed a positive serial indirect effect of time pressure (but not of problem solving or planning and decision making) on workplace procrastination via increased hindrance appraisal and subsequently increased self-regulation effort. Overall, our study showed that work characteristics are linked to workplace procrastination via within-person processes of cognitive appraisal and self-regulation. Because not all work characteristics triggered hindrance appraisal, we argue that it may make sense to further differentiate challenge stressors in the future. Moreover, cognitive appraisals affected self-regulation effort only on the within-person level. On the between-person level self-regulation effort was strongly negatively related with occupational self-efficacy. Thus, we conclude that depending the perspective on procrastination (e.g., differential psychology perspective vs. situational perspective) different variables will be considered relevant to explain the emergence of procrastination.

18.
Z Arztl Fortbild Qualitatssich ; 101(10): 661-6, 2007.
Artigo em Alemão | MEDLINE | ID: mdl-18309891

RESUMO

INTRODUCTION: Following the recent amendment to the Medical Education Act in Germany (Approbationsordnung 2002) and the abolition of the preliminary approbation for early residency (AiP), the discussion increasingly focuses on the restructuring of German post-graduate medical training. The training should include well-defined learning objectives and an educational concept with a central emphasis on communication skills training. In the German-speaking countries there has as yet been no publication of a structured training course for the improvement of communication skills in the context of post-graduate education. METHODS: Jointly designed by the University of Heidelberg's Clinic of Internal Medicine and Clinic of Paediatrics, this study aimed to measure the effect of a training programme for handling problems and difficult situations arising in the communication with parents and patients. 28 paediatric residents took part in a randomised controlled trial using standardized patients and video-feedback (intervention group: N = 14; control group: N = 14). Upon completion of the study, the control group also received training and was subsequently evaluated. The training course consisted of four units, lasting 90 minutes each. Both the acceptance of the training units and the self-evaluation of communication skills in dealing with parents were subject to assessment. RESULTS: The participating residents acknowledged the training course to be an extremely useful tool for improving their communication skills and confidence in dealing with the parents of ill children. A pre-post comparison of self-assessed communication skills revealed a significant increase in the intervention group, but not in the control group. DISCUSSION: The structured training course presented in the current study proved highly effective and should serve as a model for a compulsory component of a post-graduate training.


Assuntos
Educação Baseada em Competências/métodos , Currículo/normas , Educação Médica Continuada , Relações Médico-Paciente , Comunicação , Educação Baseada em Competências/organização & administração , Educação Baseada em Competências/normas , Alemanha , Humanos , Ensino/métodos
19.
Exp Psychol ; 50(1): 49-54, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12629960

RESUMO

In a laboratory experiment, we compare the relative impact of two possible determinants of intuitive evaluative judgments: ease of recognition and total value of prior encounters with a target. Participants encode daily return values of shares on the stock market while watching videotaped ads on the computer screen. This dual-task procedure ensures that participants subsequently lack relevant event memories and thus have to rely on their intuition when evaluating the targets. In the presentation, the share appearing least frequently produced the highest sum of returns. In contrast, the share appearing most frequently produced the lowest sum of returns. Evaluative judgments reveal a preference for the share with the highest sum of returns, although, as evident from recognition latencies, it was the one that was more difficult to recognize. The results provide evidence for the value-account model of implicit attitude formation (Betsch, Plessner, Schwieren, & Gütig, 2001), which predicts that intuitive evaluative judgments reflect the total value of prior encounters.


Assuntos
Intuição , Reconhecimento Psicológico , Adulto , Feminino , Humanos , Masculino
20.
Semin Immunopathol ; 36(6): 627-40, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25288477

RESUMO

The constant region of IgG antibodies mediates antiviral activities upon engaging host Fcγ receptors (FcγRs) expressed by a variety of immune cells, such as antibody-dependent cellullar cytotoxcity (ADCC) executed by natural killer (NK)cells. Human cytomegalovirus (HCMV) is unique among viruses by encoding also an array of several Fcγ-binding glycoproteins with cell surface disposition and concomitant incorporation into the virion. Evidence is increasing that the virus-encoded Fcγ receptors differ in their Fcγ binding mode but effectively operate as adversaries of host FcγRs since they are able to prevent IgG-mediated triggering of activating host FcγRs, i.e., FcγRI, FcγRIIA, and FcγRIIIA. Here we discuss virus-encoded FcγRs as the first known HCMV inhibitors of IgG-mediated immunity which could account for the limited efficacy of HCMV hyperimmune globulin in clinical settings. A better understanding of their molecular mode of action opens up new perspectives for improving IgG therapies against HCMV disease.


Assuntos
Infecções por Citomegalovirus/imunologia , Citomegalovirus/genética , Citomegalovirus/imunologia , Receptores de IgG/genética , Proteínas Virais/genética , Imunidade Adaptativa , Animais , Anticorpos Antivirais/imunologia , Proteínas de Transporte/metabolismo , Infecções por Citomegalovirus/genética , Infecções por Citomegalovirus/metabolismo , Infecções por Citomegalovirus/terapia , Humanos , Imunidade Inata , Imunoglobulina G/imunologia , Imunomodulação , Imunoterapia , Ligantes , Ligação Proteica , Receptores de IgG/química , Receptores de IgG/metabolismo , Proteínas Virais/metabolismo
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