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2.
Antimicrob Resist Infect Control ; 13(1): 20, 2024 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-38355509

RESUMEN

BACKGROUND: In most of Europe and especially in Germany, there is currently a concerning rise in the number of hospital-acquired infections due to vancomycin-resistant Enterococcus faecium (VREfm). Therefore, there is a need to improve our understanding of the way VREfm spreads in hospitals. In this study, we investigated the molecular epidemiology of VREfm isolates from the first appearance at our university hospital in 2004 until 2010. There is only very scarce information about the molecular epidemiology of VREfm from this early time in Germany. METHODS: Our analysis includes all available first VREfm isolates of each patient at our tertiary care center collected during the years 2004-2010. If available, additional consecutive VREfm isolates from some patients were analyzed. We used multilocus sequence typing (MLST) and core genome multilocus sequence typing (cgMLST) for the analysis and description of nosocomial transmission pathways as well as the detection of outbreaks. RESULTS: VREfm isolates from 158 patients and 76 additional subsequent patient isolates were included in the analysis. Until 2006, detections of VREfm remained singular cases, followed by a peak in the number of VREfm cases in 2007 and 2008 with a subsequent decline to baseline in 2010. MLST and cgMLST analysis show significant changes in the dominant sequence types (STs) and complex types (CTs) over the study period, with ST192 and ST17 being responsible for the peak in VREfm cases in 2007 and 2008. The four largest clusters detected during the study period are comprised of these two STs. Cluster analysis shows a focus on specific wards and departments for each cluster. In the early years of this study (2004-2006), all analyzed VREfm stemmed from clinical specimens, whereas since 2007, approximately half of the VREfm were detected by screening. Of the 234 VREfm isolates analyzed, 96% had a vanB and only 4% had a vanA resistance genotype. CONCLUSIONS: This retrospective study contributes significant knowledge about regional VREfm epidemiology from this early VREfm period in Germany. One remarkable finding is the striking dominance of vanB-positive VREfm isolates over the entire study period, which is in contrast with countrywide data. Analysis of cgMLST shows the transition from sporadic VRE cases at our institution to a sharp increase in VRE numbers triggered by oligoclonal spread and specific outbreak clusters with the dominance of ST192 and ST17.


Asunto(s)
Enterococcus faecium , Enterococos Resistentes a la Vancomicina , Humanos , Vancomicina , Estudios Retrospectivos , Epidemiología Molecular , Tipificación de Secuencias Multilocus , Enterococcus faecium/genética , Centros de Atención Terciaria , Atención Terciaria de Salud , Enterococos Resistentes a la Vancomicina/genética
3.
Sci Rep ; 13(1): 19025, 2023 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-37923898

RESUMEN

Hypervirulent Klebsiella pneumoniae strains (hvKp) can cause invasive community-acquired infections in healthy patients of all ages. In this study, the prevalence of putative hvKp in a German tertiary center was investigated and hvKp were characterized by phenotypic and molecular assays. All K. pneumoniae isolates in routine microbiological diagnostics from a single center were screened by string-testing over a period of 6 months. String-test positive (≥ 0.5 mm) isolates were re-evaluated on different media and under various conditions (aerobe, anaerobe). For string-test positive isolates, genes (magA, iutA, rmpA and rmpA2) associated with hypermucoviscosity and hypervirulence were amplified by multiplex PCR. PCR-positive isolates were subjected to whole-genome sequencing and sedimentation and biofilm formation assays. From 1310 screened K. pneumoniae isolates in clinical routine 100 isolates (7.6%) were string test positive. From these, 9% (n = 9) were defined as putative hvKp (string-test+/PCR+). Highest rate of string-test-positive isolates was observed on MacConkey agar under aerobic conditions. Amongst these nine putative hvKp isolates, the international lineage ST23 carrying hvKp-plasmid pKpVP-1 was the most common, but also a rare ST86 with pKpVP-2 was identified. All nine isolates showed hypermucoviscosity and weak biofilm formation. In conclusion, 9% of string-positive, respectively 0.69% of all K. pneumoniae isolates from routine were defined as putative hypervirulent. MacConkey agar was the best medium for hvKp screening.


Asunto(s)
Infecciones por Klebsiella , Klebsiella pneumoniae , Humanos , Factores de Virulencia/genética , Virulencia/genética , Agar , Reacción en Cadena de la Polimerasa Multiplex , Infecciones por Klebsiella/diagnóstico , Infecciones por Klebsiella/epidemiología , Infecciones por Klebsiella/microbiología , Antibacterianos
4.
Infection ; 51(5): 1557-1562, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37217812

RESUMEN

INTRODUCTION: Bloodstream infections with Enterococcus faecalis are associated with relevant morbidity and mortality. Targeted antimicrobial therapy is essential. The choice of an adequate treatment may be challenging when susceptibility testing offers different options. Selective reporting of antibiotic susceptibility test results might lead to a more tailored antibiotic therapy and could therefore be an important antimicrobial stewardship program intervention. The aim of this study was to analyse whether the introduction of selective reporting of antibiotic test results leads to a more targeted antibiotic therapy in patients with bloodstream infection with Enterococcus faecalis. METHODS: This study was performed as a retrospective cohort study at the University Hospital Regensburg, Germany. All patients with blood cultures positive for Enterococcus faecalis between March 2003 and March 2022 were analysed. In February 2014 selective reporting of antibiotic susceptibility test results omitting sensitivity results for agents not recommended was introduced. RESULTS: 263 patients with blood cultures positive for Enterococcus faecalis were included. After introduction of selective reporting of antibiotic tests (AI) significantly more patients received ampicillin than before introduction of selective reporting (BI) (9.6% BI vs. 34.6% AI, p < 0.001). CONCLUSION: Selective reporting of antibiotic susceptibility test results led to a significantly higher use of ampicillin.


Asunto(s)
Enterococcus faecium , Infecciones por Bacterias Grampositivas , Sepsis , Humanos , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Enterococcus faecalis , Estudios Retrospectivos , Pruebas de Sensibilidad Microbiana , Ampicilina , Infecciones por Bacterias Grampositivas/diagnóstico , Infecciones por Bacterias Grampositivas/tratamiento farmacológico
5.
PLoS One ; 18(1): e0280502, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36662898

RESUMEN

BACKGROUND: Patients with COVID-19 and severe acute respiratory failure may require veno-venous extracorporeal membrane oxygenation (VV ECMO). Yet, this procedure is resource-intensive and high mortality rates have been reported. Thus, predictors for identifying patients who will benefit from VV ECMO would be helpful. METHODS: This retrospective study included 129 patients with COVID-19 and severe acute respiratory failure, who had received VV ECMO at the University Medical Center Regensburg, Germany, between 1 March 2020 and 31 December 2021. Patient-specific factors and relevant intensive-care parameters at the time of the decision to start VV ECMO were investigated regarding their value as predictors of patient survival. In addition, the intensive-care course of the first 10 days of VV ECMO was compared between survivors and patients who had died in the intensive care unit. RESULTS: The most important parameters for predicting outcome were patient age and platelet count, which differed significantly between survivors and non-survivors (age: 52.6±8.1 vs. 57.4±10.1 years, p<0.001; platelet count before VV ECMO: 321.3±132.2 vs. 262.0±121.0 /nL, p = 0.006; average on day 10: 199.2±88.0 vs. 147.1±57.9 /nL, p = 0.002). A linear regression model derived from parameters collected before the start of VV ECMO only included age and platelet count. Patients were divided into two groups by using receiver operating characteristics (ROC) analysis: group 1: 78% of patients, mortality 26%; group 2: 22% of patients, mortality 75%. A second linear regression model included average blood pH, minimum paO2, and average pump flow on day 10 of VV ECMO in addition to age and platelet count. The ROC curve resulted in two cut-off values and thus in three groups: group 1: 25% of patients, mortality 93%; group 2: 45% of patients, mortality 31%; group 3: 30% of patients, mortality 0%.


Asunto(s)
COVID-19 , Oxigenación por Membrana Extracorpórea , Síndrome de Dificultad Respiratoria , Insuficiencia Respiratoria , Humanos , Adulto , Persona de Mediana Edad , Oxigenación por Membrana Extracorpórea/métodos , Pronóstico , Estudios Retrospectivos , COVID-19/terapia , Cuidados Críticos , Insuficiencia Respiratoria/terapia
6.
Artículo en Inglés | MEDLINE | ID: mdl-35206511

RESUMEN

Millions of people use public transportation daily worldwide and frequently touch surfaces, thereby producing a reservoir of microorganisms on surfaces increasing the risk of transmission. Constant occupation makes sufficient cleaning difficult to achieve. Thus, an autonomous, permanent, antimicrobial coating (AMC) could keep down the microbial burden on such surfaces. A photodynamic AMC was applied to frequently touched surfaces in buses. The microbial burden (colony forming units, cfu) was determined weekly and compared to equivalent surfaces in buses without AMC (references). The microbial burden ranged from 0-209 cfu/cm2 on references and from 0-54 cfu/cm2 on AMC. The means were 13.4 ± 29.6 cfu/cm2 on references and 4.5 ± 8.4 cfu/cm2 on AMC (p < 0.001). The difference in microbial burden on AMC and references was almost constant throughout the study. Considering a hygiene benchmark of 5 cfu/cm2, the data yield an absolute risk reduction of 22.6% and a relative risk reduction of 50.7%. In conclusion, photodynamic AMC kept down the microbial burden, reducing the risk of transmission of microorganisms. AMC permanently and autonomously contributes to hygienic conditions on surfaces in public transportation. Photodynamic AMC therefore are suitable for reducing the microbial load and closing hygiene gaps in public transportation.


Asunto(s)
Antiinfecciosos , Antibacterianos , Recuento de Colonia Microbiana , Humanos , Vehículos a Motor , Transportes
7.
J Exp Med ; 219(1)2022 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-34919140

RESUMEN

Metastasis is the major cause of death in cancer patients. Circulating tumor cells need to migrate through the endothelial layer of blood vessels to escape the hostile circulation and establish metastases at distant organ sites. Here, we identified the membrane-bound metalloprotease ADAM17 on endothelial cells as a key driver of metastasis. We show that TNFR1-dependent tumor cell-induced endothelial cell death, tumor cell extravasation, and subsequent metastatic seeding is dependent on the activity of endothelial ADAM17. Moreover, we reveal that ADAM17-mediated TNFR1 ectodomain shedding and subsequent processing by the γ-secretase complex is required for the induction of TNF-induced necroptosis. Consequently, genetic ablation of ADAM17 in endothelial cells as well as short-term pharmacological inhibition of ADAM17 prevents long-term metastases formation in the lung. Thus, our data identified ADAM17 as a novel essential regulator of necroptosis and as a new promising target for antimetastatic and advanced-stage cancer therapies.


Asunto(s)
Proteína ADAM17/antagonistas & inhibidores , Células Endoteliales/metabolismo , Necroptosis , Neoplasias/etiología , Neoplasias/patología , Animales , Antineoplásicos/farmacología , Biomarcadores , Biomarcadores de Tumor , Comunicación Celular , Muerte Celular , Susceptibilidad a Enfermedades/inmunología , Humanos , Necroptosis/genética , Invasividad Neoplásica , Metástasis de la Neoplasia , Siembra Neoplásica , Neoplasias/metabolismo , Neoplasias/terapia , Proteolisis , Receptores Tipo I de Factores de Necrosis Tumoral/metabolismo , Microambiente Tumoral/efectos de los fármacos , Microambiente Tumoral/genética , Microambiente Tumoral/inmunología , Factor de Necrosis Tumoral alfa/metabolismo
8.
Crit Rev Microbiol ; 48(5): 531-564, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34699296

RESUMEN

Recent reports provide evidence that contaminated healthcare environments represent major sources for the acquisition and transmission of pathogens. Antimicrobial coatings (AMC) may permanently and autonomously reduce the contamination of such environmental surfaces complementing standard hygiene procedures. This review provides an overview of the current status of AMC and the demands to enable a rational application of AMC in health care settings. Firstly, a suitable laboratory test norm is required that adequately quantifies the efficacy of AMC. In particular, the frequently used wet testing (e.g. ISO 22196) must be replaced by testing under realistic, dry surface conditions. Secondly, field studies should be mandatory to provide evidence for antimicrobial efficacy under real-life conditions. The antimicrobial efficacy should be correlated to the rate of nosocomial transmission at least. Thirdly, the respective AMC technology should not add additional bacterial resistance development induced by the biocidal agents and co- or cross-resistance with antibiotic substances. Lastly, the biocidal substances used in AMC should be safe for humans and the environment. These measures should help to achieve a broader acceptance for AMC in healthcare settings and beyond. Technologies like the photodynamic approach already fulfil most of these AMC requirements.


Asunto(s)
Antiinfecciosos , Antibacterianos , Antiinfecciosos/farmacología , Hospitales , Humanos , Higiene
9.
Microorganisms ; 11(1)2022 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-36677346

RESUMEN

PURPOSE: Community-acquired methicillin-resistant Staphylococcus aureus strains (CA-MRSA) are spread worldwide and often cause recurring and persistent infections in humans. CA-MRSA strains frequently carry Panton-Valentine leukocidin (PVL) as a distinctive virulence factor. This study investigates the molecular epidemiology, antibiotic resistance and clinical characteristics of PVL-positive MRSA strains in Northern Bavaria, Germany, isolated over an eight-year period. METHODS: Strains were identified by MALDI-TOF MS and antibiotic susceptibility was tested by automated microdilution (VITEK 2) or disk diffusion. PVL-encoding genes and mecA were detected by PCR. MRSA clonal complexes (CC) and lineages were assigned by genotyping via DNA microarray and spa-typing. RESULTS: In total, 131 PVL-positive MRSA were collected from five hospital sites between 2009 and 2016. Predominant lineages were CC8-MRSA-[IV+ACME], USA300 (27/131; 20.6%); CC30-MRSA-IV, Southwest Pacific Clone (26/131; 19.8%) and CC80-MRSA-IV (25/131; 19.1%). Other CCs were detected less frequently. Resistance against erythromycin and clindamycin was prevalent, whereas all strains were sensitive towards vancomycin and linezolid. In total, 100 cases (76.3%) were causally linked to an infection. The majority (102/131; 77.9%) of isolates were detected in skin swabs or swabs from surgical sites. CONCLUSIONS: During the sample period we found an increase in the PVL-positive MRSA lineages CC30 and CC1. Compared to less-abundant lineages CC1 or CC22, the predominant lineages CC8, CC30 and CC80 harbored a broader resistance spectrum. Furthermore, these lineages are probably associated with a travel and migration background. In the spatio-temporal setting we investigated, these were arguably drivers of diversification and change in the landscape of PVL-positive MRSA.

10.
Front Genet ; 12: 723958, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34868203

RESUMEN

In the context of microarray-based epidemiological typing of the clonal organism Staphylococcus aureus/MRSA, a strain was identified that did not belong to known clonal complexes. The molecular analysis by microarray-based typing yielded signals suggesting that it was a mosaic or hybrid strain of two lineages. To verify this result, the isolate was sequenced with both, short-read Illumina and long-read Nanopore technologies and analysed in detail. This supported the hypothesis that the genome of this strain, ST6610-MRSA-IVg comprised of segments originating from two different clonal complexes (CC). While the backbone of the strain's genome, i.e., roughly 2 megabases, belongs to CC8, a continuous insert of 894 kb (approx. 30% of the genome) originated from CC140. Beside core genomic markers in the normal succession and orientation, this insert also included the mecA gene, coding for PbP2a and causing methicillin resistance, localised on an SCCmec IVg element. This particular SCCmec type was also previously observed in CC140 MRSA from African countries. A second conspicuous observation was the presence of the trimethoprim resistance gene dfrG within on a prophage that occupied an attachment site normally used by Panton-Valentine Leucocidin phages. This observation could indicate a role of large-scale chromosomal recombination in the evolution of S. aureus as well as a role of phages in the dissemination of antibiotic resistance genes.

11.
Front Pediatr ; 9: 721518, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34778127

RESUMEN

Background: Opening schools and keeping children safe from SARS-CoV-2 infections at the same time is urgently needed to protect children from direct and indirect consequences of the COVID-19 pandemic. To achieve this goal, a safe, efficient, and cost-effective SARS-CoV-2 testing system for schools in addition to standard hygiene measures is necessary. Methods: We implemented the screening WICOVIR concept for schools in the southeast of Germany, which is based on gargling at home, pooling of samples in schools, and assessment of SARS-CoV-2 by pool rRT-PCR, performed decentralized in numerous participating laboratories. Depooling was performed if pools were positive, and results were transmitted with software specifically developed for the project within a day. Here, we report the results after the first 13 weeks in the project. Findings: We developed and implemented the proof-of-concept test system within a pilot phase of 7 weeks based on almost 17,000 participants. After 6 weeks in the main phase of the project, we performed >100,000 tests in total, analyzed in 7,896 pools, identifying 19 cases in >100 participating schools. On average, positive children showed an individual CT value of 31 when identified in the pools. Up to 30 samples were pooled (mean 13) in general, based on school classes and attached school staff. All three participating laboratories detected positive samples reliably with their previously established rRT-PCR standard protocols. When self-administered antigen tests were performed concomitantly in positive cases, only one of these eight tests was positive, and when antigen tests performed after positive pool rRT-PCR results were already known were included, 3 out of 11 truly positive tests were also identified by antigen testing. After 3 weeks of repetitive WICOVIR testing twice weekly, the detection rate of positive children in that cohort decreased significantly from 0.042 to 0.012 (p = 0.008). Interpretation: Repeated gargle pool rRT-PCR testing can be implemented quickly in schools. It is an effective, valid, and well-received test system for schools, superior to antigen tests in sensitivity, acceptance, and costs.

12.
Cells ; 10(11)2021 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-34831323

RESUMEN

Signaling via death receptor family members such as TNF-R1 mediates pleiotropic biological outcomes ranging from inflammation and proliferation to cell death. Pro-survival signaling is mediated via TNF-R1 complex I at the cellular plasma membrane. Cell death induction requires complex IIa/b or necrosome formation, which occurs in the cytoplasm. In many cell types, full apoptotic or necroptotic cell death induction requires the internalization of TNF-R1 and receptosome formation to properly relay the signal inside the cell. We interrogated the role of the enzyme A disintegrin and metalloprotease 17 (ADAM17)/TACE (TNF-α converting enzyme) in death receptor signaling in human hematopoietic cells, using pharmacological inhibition and genetic ablation. We show that in U937 and Jurkat cells the absence of ADAM17 does not abrogate, but rather increases TNF mediated cell death. Likewise, cell death triggered via DR3 is enhanced in U937 cells lacking ADAM17. We identified ADAM17 as the key molecule that fine-tunes death receptor signaling. A better understanding of cell fate decisions made via the receptors of the TNF-R1 superfamily may enable us, in the future, to more efficiently treat infectious and inflammatory diseases or cancer.


Asunto(s)
Proteína ADAM17/metabolismo , Receptores Tipo I de Factores de Necrosis Tumoral/metabolismo , Proteína ADAM17/antagonistas & inhibidores , Proteína ADAM17/deficiencia , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Muerte Celular , Supervivencia Celular , Endocitosis , Humanos , Células Jurkat , Células MCF-7 , Modelos Biológicos , FN-kappa B/metabolismo , Miembro 25 de Receptores de Factores de Necrosis Tumoral/metabolismo , Transducción de Señal , Factor de Necrosis Tumoral alfa/farmacología , Células U937
13.
Medicine (Baltimore) ; 100(34): e27060, 2021 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-34449497

RESUMEN

ABSTRACT: Antibiotic stewardship (ABS) programs intend to improve outcomes of nosocomial infections and to counteract the emergence of further antimicrobial resistances. At the anesthesiologic-neurosurgical intensive care unit (ICU) of the University Medical Center Regensburg (Germany) we implemented a standard operating procedure (SOP) with clear instructions for the preanalytical handling and storage of microbiological samples. We intended to find out whether the instructions given in the SOP led to a higher rate of ideal material being sent to the laboratory and to overall better quality of the received results.We retraced retrospectively all samples taken in cases of suspected pneumonia, urinary tract infection, bloodstream infection, catheter infection associated with a central venous or arterial catheter and ventriculitis due to external ventricular drainage as well as all smears taken for the screening for multi-resistant bacteria within a time period of 1 year before to 1 year after the implementation of the SOP.In the case of suspected pneumonia and urinary tract infection, large amounts of ideal material were sent to the microbiological laboratory. A remarkable improvement after the implementation of the SOP, however, could only be observed regarding the number of urine samples taken from older urinary catheters, which was significantly lower in the "SOP group". Samples for microbiological diagnostics were taken much more often in the daytime, although storage of the probes did not lead to worse results.Concrete instructions enable adequate preanalytical handling of microbiological probes. However, we could not recognize substantial improvements probably due to a preexisting high process quality on the ICU. Microbiological diagnostics during the night shift has to be improved.


Asunto(s)
Protocolos Clínicos/normas , Unidades de Cuidados Intensivos/organización & administración , Técnicas Microbiológicas/normas , Programas de Optimización del Uso de los Antimicrobianos , Infección Hospitalaria/microbiología , Infección Hospitalaria/prevención & control , Alemania , Humanos , Unidades de Cuidados Intensivos/normas , Neurocirugia , Estudios Retrospectivos , Factores de Tiempo
14.
Microb Genom ; 7(7)2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34223815

RESUMEN

This study investigated the evolution and epidemiology of the community-associated and multidrug-resistant Staphylococcus aureus clone European CC1-MRSA-IV. Whole-genome sequences were obtained for 194 European CC1-MRSA-IV isolates (189 of human and 5 of animal origin) from 12 countries, and 10 meticillin-susceptible precursors (from North-Eastern Romania; all of human origin) of the clone. Phylogenetic analysis was performed using a maximum-likelihood approach, a time-measured phylogeny was reconstructed using Bayesian analysis, and in silico microarray genotyping was performed to identify resistance, virulence-associated and SCCmec (staphylococcal cassette chromosome mec) genes. Isolates were typically sequence type 1 (190/204) and spa type t127 (183/204). Bayesian analysis indicated that European CC1-MRSA-IV emerged in approximately 1995 before undergoing rapid expansion in the late 1990s and 2000s, while spreading throughout Europe and into the Middle East. Phylogenetic analysis revealed an unstructured meticillin-resistant S. aureus (MRSA) population, lacking significant geographical or temporal clusters. The MRSA were genotypically multidrug-resistant, consistently encoded seh, and intermittently (34/194) encoded an undisrupted hlb gene with concomitant absence of the lysogenic phage-encoded genes sak and scn. All MRSA also harboured a characteristic ~5350 nt insertion in SCCmec adjacent to orfX. Detailed demographic data from Denmark showed that there, the clone is typically (25/35) found in the community, and often (10/35) among individuals with links to South-Eastern Europe. This study elucidated the evolution and epidemiology of European CC1-MRSA-IV, which emerged from a meticillin-susceptible lineage prevalent in North-Eastern Romania before disseminating rapidly throughout Europe.


Asunto(s)
Farmacorresistencia Bacteriana Múltiple/genética , Genoma Bacteriano/genética , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/genética , Infecciones Estafilocócicas/epidemiología , Animales , Antibacterianos/farmacología , Infecciones Comunitarias Adquiridas/microbiología , Infección Hospitalaria/microbiología , Europa (Continente)/epidemiología , Evolución Molecular , Humanos , Staphylococcus aureus Resistente a Meticilina/clasificación , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Filogenia , Secuenciación Completa del Genoma
15.
Cancers (Basel) ; 13(11)2021 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-34063813

RESUMEN

Death-receptor-mediated signaling results in either cell death or survival. Such opposite signaling cascades emanate from receptor-associated signaling complexes, which are often formed in different subcellular locations. The proteins involved are frequently post-translationally modified (PTM) by ubiquitination, phosphorylation, or glycosylation to allow proper spatio-temporal regulation/recruitment of these signaling complexes in a defined cellular compartment. During the last couple of years, increasing attention has been paid to the reversible cysteine-centered PTM S-palmitoylation. This PTM regulates the hydrophobicity of soluble and membrane proteins and modulates protein:protein interaction and their interaction with distinct membrane micro-domains (i.e., lipid rafts). We conclude with which functional and mechanistic roles for S-palmitoylation as well as different forms of membrane micro-domains in death-receptor-mediated signal transduction were unraveled in the last two decades.

16.
Laryngorhinootologie ; 100(6): 434-442, 2021 06.
Artículo en Alemán | MEDLINE | ID: mdl-33851374

RESUMEN

Increasing normative demands on patient safety and quality assurance measures, but also the problem of multi-resistant germs and pathogens with a high potential for infection, increase the need for hygienically correct work.In this study, hygienically relevant potential sources of contamination in ENT examinations were to be identified and possible improvement strategies examined.A complete ENT examination was performed by 5 examiners with different professional experience, whose gloves were wetted with fluorescent lotion prior to the examination. Contaminations especially on the examination unit and on the instruments were identified. The potential risk of transmission of pathogens to subsequent patients was assessed using a specially developed score. Various strategies to reduce identified contamination possibilities were developed and thought through.The score of the investigators was very high with an average of 87.4 points (±3.6). The implementation of individual hygiene measures during the examination process would lead to a significant reduction of the score and thus to an improvement in hygiene: No shaking of hands (81.8), additional disinfection of patient's chair (79.8), disinfection of important surfaces (69.8), provision of standard instruments (60.2) or all instruments (32.2), disinfection of all relevant surfaces and provision of all instruments (7.4).The results show very clearly that an ENT examination is a complex procedure from the point of view of hygiene. For reliable protection against possible transmission events, a structured bundling of hygiene measures is therefore necessary.


Asunto(s)
Desinfección , Higiene , Fluorescencia , Humanos
17.
Am J Infect Control ; 49(7): 912-918, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33428983

RESUMEN

BACKGROUND: Hand hygiene is essential for infection prevention. This study aimed to find a suitable theoretical model and identify critical facilitators and barriers to explain hospital visitors' hand hygiene practice. METHODS: Visitors in 4 hospitals were observed and asked to give explanations for using or not using the hand rub dispenser. The written explanations of N = 838 participants were coded according to three theoretical models: Theory of Planned Behavior, Health Action Process Approach (HAPA), and Theoretical Domains Framework (TDF). RESULTS: Self-reported hand hygiene behavior differed from observed behavior, with 15.75% wrongly claiming to have cleaned their hands. Critical facilitators for hand hygiene were attitude toward the behavior,subjective norm, outcome expectancies, risk perception, planning, action control, knowledge and skills, motivation and goals, and social influences. Key barriers included perceived behavioral control; barriers and resources; memory, attention, and decision processes; and environmental context and resources. CONCLUSIONS: Visitors' self-reported hand hygiene behavior is over-reported. Both HAPA and TDF were identified as suitable theoretical models for explaining visitor's hand hygiene practice. Future behavior change interventions should focus on (1) visibility and accessibility of cleaning products; (2) informing laypeople about their role regarding infection prevention; and (3) leveraging social influence processes.


Asunto(s)
Higiene de las Manos , Hospitales , Humanos , Motivación , Autoinforme
18.
PLoS One ; 15(9): e0239444, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32986726

RESUMEN

INTRODUCTION: Infection prevention and speaking up on errors are core qualities of health care providers. Heuristic effects (e.g. overconfidence) may impair behavior in daily routine, while speaking up can be inhibited by hierarchical barriers and medical team factors. Aim of this investigation was to determine, how medical students experience these difficulties for hand hygiene in daily routine. METHODS: On the base of prior investigations we developed a questionnaire with 5-point Likert ordinal scaled items and free text entries. This was tested for validity and reliability (Cronbach's Alpha 0.89). Accredited German, Swiss and Austrian universities were contacted and medical students asked to participated in the anonymous online survey. Quantitative statistics used parametric and non-parametric tests and effect size calculations according to Lakens. Qualitative data was coded according to Janesick. RESULTS: 1042 undergraduates of 12 universities participated. All rated their capabilities in hand hygiene and feedback reception higher than those of fellow students, nurses and physicians (p<0.001). Half of the participants rating themselves to be best educated, realized that faulty hand hygiene can be of lethal effect. Findings were independent from age, sex, academic course and university. Speaking-up in case of omitted hand hygiene was rated to be done seldomly and most rare on persons of higher hierarchic levels. Qualitative results of 164 entries showed four main themes: 1) Education methods in hand hygiene are insufficient, 2) Hierarchy barriers impair constructive work place culture 3) Hygiene and feedback are linked to medical ethics and 4) There is no consequence for breaking hygiene rules. DISCUSSION: Although partially limited by the selection bias, this study confirms the overconfidence-effects demonstrated in post-graduates in other settings and different professions. The independence from study progress suggests, that the effect occurs before start of the academic course with need for educational intervention at the very beginning. Qualitative data showed that used methods are insufficient and contradictory work place behavior in hospitals are frustrating. Even 20 years after "To err is human", work place culture still is far away from the desirable.


Asunto(s)
Cognición , Higiene de las Manos , Lenguaje , Competencia Profesional , Estudiantes de Medicina/psicología , Adolescente , Adulto , Femenino , Humanos , Masculino , Seguridad del Paciente , Adulto Joven
19.
Euro Surveill ; 25(25)2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32613938

RESUMEN

We investigated why a clinical meticillin-resistant Staphylococcus aureus (MRSA) isolate yielded false-negative results with some commercial PCR tests for MRSA detection. We found that an epidemic European CC1-MRSA-IV clone generally exhibits this behaviour. The failure of the assays was attributable to a large insertion in the orfX/SCCmec integration site. To ensure the reliability of molecular MRSA tests, it is vital to monitor emergence of new SCCmec types and junction sites.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Infecciones Estafilocócicas/diagnóstico , Austria/epidemiología , Reacciones Falso Negativas , Femenino , Alemania/epidemiología , Humanos , Irlanda/epidemiología , Staphylococcus aureus Resistente a Meticilina/genética , Persona de Mediana Edad , Infecciones Estafilocócicas/epidemiología
20.
Cell Commun Signal ; 17(1): 90, 2019 08 05.
Artículo en Inglés | MEDLINE | ID: mdl-31382980

RESUMEN

BACKGROUND: Binding of tumor necrosis factor (TNF) to TNF-receptor 1 (TNF-R1) can induce either cell survival or cell death. The selection between these diametrically opposed effects depends on the subcellular location of TNF-R1: plasma membrane retention leads to survival, while endocytosis leads to cell death. How the respective TNF-R1 associated signaling complexes are recruited to the distinct subcellular location is not known. Here, we identify palmitoylation of TNF-R1 as a molecular mechanism to achieve signal diversification. METHODS: Human monocytic U937 cells were analyzed. Palmitoylated proteins were enriched by acyl resin assisted capture (AcylRAC) and analyzed by western blot and mass spectrometry. Palmitoylation of TNF-R1 was validated by metabolic labeling. TNF induced depalmitoylation and involvement of APT2 was analyzed by enzyme activity assays, pharmacological inhibition and shRNA mediated knock-down. TNF-R1 palmitoylation site analysis was done by mutated TNF-R1 expression in TNF-R1 knock-out cells. Apoptosis (nuclear DNA fragmentation, caspase 3 assays), NF-κB activation and TNF-R1 internalization were used as biological readouts. RESULTS: We identify dynamic S-palmitoylation as a new mechanism that controls selective TNF signaling. TNF-R1 itself is constitutively palmitoylated and depalmitoylated upon ligand binding. We identified the palmitoyl thioesterase APT2 to be involved in TNF-R1 depalmitoylation and TNF induced NF-κB activation. Mutation of the putative palmitoylation site C248 interferes with TNF-R1 localization to the plasma membrane and thus, proper signal transduction. CONCLUSIONS: Our results introduce palmitoylation as a new layer of dynamic regulation of TNF-R1 induced signal transduction at a very early step of the TNF induced signaling cascade. Understanding the underlying mechanism may allow novel therapeutic options for disease treatment in future.


Asunto(s)
Lipoilación , Receptores Tipo I de Factores de Necrosis Tumoral/metabolismo , Transducción de Señal , Línea Celular , Regulación de la Expresión Génica , Humanos , FN-kappa B/metabolismo , Transporte de Proteínas , Tioléster Hidrolasas/metabolismo
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