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1.
Biochem Biophys Res Commun ; 672: 45-53, 2023 09 10.
Artículo en Inglés | MEDLINE | ID: mdl-37336124

RESUMEN

Secretory proteins are used by pathogenic bacteria to manipulate the host systems and compete with other microorganisms, thereby enabling their survival in their host. Similar to other bacteria, secretory proteins of Mycobacterium tuberculosis also play a pivotal role in evading immune response within hosts, thereby leading to acute and latent tuberculosis infection. Prokaryotes have several classes of bacterial secretory systems out of which the Sec and Tat pathways are the most conserved in Mtb to transport proteins across the cytoplasmic membrane. Here, we report the crystal structure of a secretory protein, Rv0398c determined to 1.9 Å resolution. The protein comprises a core of antiparallel ß sheets surrounded by α helices adopting a unique ß sandwich fold. Structural comparison with other secretory proteins in Mtb and other pathogenic bacteria reveals that Rv0398c may be secreted via the Sec pathway. Our structural and in silico analyses thus provide mechanistic insights into the pathway adopted by Mtb to transport out secretory protein, Rv0398c which will facilitate the invasion to the host immune system.


Asunto(s)
Proteínas Bacterianas , Mycobacterium tuberculosis , Proteínas Bacterianas/metabolismo , Proteínas de Transporte de Membrana/metabolismo , Mycobacterium tuberculosis/metabolismo , Proteínas Portadoras/metabolismo , Transporte Biológico
2.
Chemistry ; 29(23): e202203967, 2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-36799129

RESUMEN

The ephrin type-A receptor 2 (EPHA2) kinase belongs to the largest family of receptor tyrosine kinases. There are several indications of an involvement of EPHA2 in the development of infectious diseases and cancer. Despite pharmacological potential, EPHA2 is an under-examined target protein. In this study, we synthesized a series of derivatives of the inhibitor NVP-BHG712 and triazine-based compounds. These compounds were evaluated to determine their potential as kinase inhibitors of EPHA2, including elucidation of their binding mode (X-ray crystallography), affinity (microscale thermophoresis), and selectivity (Kinobeads assay). Eight inhibitors showed affinities in the low-nanomolar regime (KD <10 nM). Testing in up to seven colon cancer cell lines that express EPHA2 reveals that several derivatives feature promising effects for the control of human colon carcinoma. Thus, we have developed a set of powerful tool compounds for fundamental new research on the interplay of EPH receptors in a cellular context.


Asunto(s)
Neoplasias Colorrectales , Pirazoles , Humanos , Pirazoles/química , Pirimidinas/farmacología , Pirimidinas/química , Línea Celular , Neoplasias Colorrectales/tratamiento farmacológico , Línea Celular Tumoral
3.
Gesundheitswesen ; 85(1): 22-25, 2023 Jan.
Artículo en Alemán | MEDLINE | ID: mdl-35738304

RESUMEN

The positive side of the Covid-19 pandemic is that it has provided a stimulation for innovations. As an example, we discuss the Pragmatic Controlled Trial (PCT), a twin study that can be used to confirm the real-world effectiveness (RWE) of health services under the non-standardized conditions of everyday care. Proof of the RWE could generally be important for health services with conditional approval. The PCT uses the Bayesian principle instead of randomization. It enables care under non-standardized everyday conditions and, by describing the endpoint-specific risks of each individual patient and by classifying the interventions, creates an unbiased evaluation in a non-experimental, but risk-stratified and controlled study. Patients expect a timely solution to their health problems. Until now, science has required sufficiently well-founded results before approving an innovation. The Covid-19 pandemic has shown that the demand for immediate and best possible care can be met through the conditional approval of a new care principle. With the PCT, we describe a procedure with which, after conditional approval, the missing data can be collected in order to successfully complete the approval process.


Asunto(s)
COVID-19 , Atención a la Salud , Humanos , Teorema de Bayes , COVID-19/epidemiología , Alemania , Pandemias/prevención & control , Proyectos de Investigación , Investigación Biomédica
4.
Biochemistry ; 61(15): 1633-1641, 2022 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-35856337

RESUMEN

Ribonucleotide reductases (RNRs) catalyze the reduction of ribonucleotides to the corresponding deoxyribonucleotides. The catalytic activity of most RNRs depends on the formation of a dimer of the catalytic subunits. The active site is located at the interface, and part of the substrate binding site and regulatory mechanisms work across the subunit in the dimer. In this study, we describe and characterize a novel domain responsible for forming the catalytic dimer in several class II RNRs. The 3D structure of the class II RNR from Rhodobacter sphaeroides reveals a so far undescribed α-helical domain in the dimer interface, which is embracing the other subunit. Genetic removal of this HUG domain leads to a severe reduction of activity paired with reduced dimerization capability. In comparison with other described RNRs, the enzyme with this domain is less dependent on the presence of nucleotides to act as allosteric effectors in the formation of dimers. The HUG domain appears to serve as an interlock to keep the dimer intact and functional even at low enzyme and/or effector concentrations.


Asunto(s)
Ribonucleótido Reductasas , Regulación Alostérica , Sitios de Unión , Dominio Catalítico , Modelos Moleculares , Ribonucleótido Reductasas/química
5.
Crit Care ; 26(1): 51, 2022 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-35227308

RESUMEN

BACKGROUND: Timely antimicrobial treatment and source control are strongly recommended by sepsis guidelines, however, their impact on clinical outcomes is uncertain. METHODS: We performed a planned secondary analysis of a cluster-randomized trial conducted from July 2011 to May 2015 including forty German hospitals. All adult patients with sepsis treated in the participating ICUs were included. Primary exposures were timing of antimicrobial therapy and delay of surgical source control during the first 48 h after sepsis onset. Primary endpoint was 28-day mortality. Mixed models were used to investigate the effects of timing while adjusting for confounders. The linearity of the effect was investigated by fractional polynomials and by categorizing of timing. RESULTS: Analyses were based on 4792 patients receiving antimicrobial treatment and 1595 patients undergoing surgical source control. Fractional polynomial analysis identified a linear effect of timing of antimicrobials on 28-day mortality, which increased by 0.42% per hour delay (OR with 95% CI 1.019 [1.01, 1.028], p ≤ 0.001). This effect was significant in patients with and without shock (OR = 1.018 [1.008, 1.029] and 1.026 [1.01, 1.043], respectively). Using a categorized timing variable, there were no significant differences comparing treatment within 1 h versus 1-3 h, or 1 h versus 3-6 h. Delays of more than 6 h significantly increased mortality (OR = 1.41 [1.17, 1.69]). Delay in antimicrobials also increased risk of progression from severe sepsis to septic shock (OR per hour: 1.051 [1.022, 1.081], p ≤ 0.001). Time to surgical source control was significantly associated with decreased odds of successful source control (OR = 0.982 [0.971, 0.994], p = 0.003) and increased odds of death (OR = 1.011 [1.001, 1.021]; p = 0.03) in unadjusted analysis, but not when adjusted for confounders (OR = 0.991 [0.978, 1.005] and OR = 1.008 [0.997, 1.02], respectively). Only, among patients with septic shock delay of source control was significantly related to risk-of death (adjusted OR = 1.013 [1.001, 1.026], p = 0.04). CONCLUSIONS: Our findings suggest that management of sepsis is time critical both for antimicrobial therapy and source control. Also patients, who are not yet in septic shock, profit from early anti-infective treatment since it can prevent further deterioration. Trial registration ClinicalTrials.gov ( NCT01187134 ). Registered 23 August 2010, NCT01187134.


Asunto(s)
Antiinfecciosos , Sepsis , Choque Séptico , Adulto , Antibacterianos/uso terapéutico , Antiinfecciosos/uso terapéutico , Mortalidad Hospitalaria , Humanos , Unidades de Cuidados Intensivos , Choque Séptico/tratamiento farmacológico
6.
BMC Anesthesiol ; 22(1): 151, 2022 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-35585496

RESUMEN

BACKGROUND: Little is known about importance and implementation of end-of-life care (EOLC) in German intensive care units (ICU). This survey analyses preferences and differences in training between "medical" (internal medicine, neurology) and "surgical" (surgery, anaesthesiology) residents during intensive care rotation. METHODS: This is a point-prevalence study, in which intensive care medicine course participants of one educational course were surveyed. Physicians from multiple ICU and university as well as non-university hospitals and all care levels were asked to participate. The questionnaire was composed of a paper and an electronic part. Demographic and structural data were prompted and EOLC data (48 questions) were grouped into six categories considering importance and implementation: category 1 (important, always implemented), 2 (important, sometimes implemented), 3 (important, never implemented) and 4-6 (unimportant, implementation always, sometimes, never). The trial is registered at the "Deutsches Register für klinische Studien (DRKS)", Study number DRKS00026619, registered on September 10th 2021, www.drks.de . RESULTS: Overall, 194/ 220 (88%) participants responded. Mean age was 29.7 years, 55% were female and 60% had scant ICU working experience. There were 64% medical and 35% surgical residents. Level of care and size of ICU differed significantly between medical and surgical (both p < 0.001). Sufficient implementation was stated for 66% of EOLC questions, room for improvement (category 2 and 3) was seen in 25, and 8% were classified as irrelevant (category 6). Areas with the most potential for improvement included prognosis and outcome and patient autonomy. There were no significant differences between medical and surgical residents. CONCLUSIONS: Even though EOLC is predominantly regarded as sufficiently implemented in German ICU of all specialties, our survey unveiled still 25% room for improvement for medical as well as surgical ICU residents. This is important, as areas of improvement potential may be addressed with reasonable effort, like individualizing EOLC procedures or setting up EOLC teams. Health care providers as well as medical societies should emphasize EOLC training in their curricula.


Asunto(s)
Médicos , Cuidado Terminal , Adulto , Cuidados Críticos , Femenino , Humanos , Unidades de Cuidados Intensivos , Masculino , Encuestas y Cuestionarios , Cuidado Terminal/métodos
7.
Schmerz ; 36(2): 128-134, 2022 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-34533652

RESUMEN

BACKGROUND: Consumption of the psychotropic plant kratom (botanical name: Mitragyna speciosa) is sometimes used for the self-medication of chronic or acute pain. An increase in the use is possible in Germany in the future. OBJECTIVE: This review provides an overview on kratom for pain specialists. The topics of the review are the pharmacological aspects, the mental effects, the effects on pain and the risks of kratom including possible addiction. MATERIAL AND METHODS: We conducted a review of literature in PubMed published until 15 January 2021 resulting in 426 publications of which 8 were specifically concerned with the topic of kratom and pain. RESULTS: In addition to other alkaloids, kratom also contains 7­hydroxymitragynine, which is active on opioid receptors. The use of kratom is not without risks, e.g. because there is no standardized form of administration as well as the possibility of direct damage to health and of addiction. DISCUSSION: There are currently no evidence-based reasons to recommend the use of kratom as an analgesic. It is important for pain specialists to ask patients about a possible abuse of kratom and to be able to inform the patients about the potential risks of kratom.


Asunto(s)
Mitragyna , Analgésicos/efectos adversos , Alemania , Humanos , Mitragyna/efectos adversos , Dolor/tratamiento farmacológico
8.
Int J Mol Sci ; 23(23)2022 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-36499657

RESUMEN

Hematological and hemorheological parameters are known to be altered in COVID-19; however, the value of combined monitoring in order to deduce disease severity is only scarcely examined. A total of 44 acute SARS-CoV-2-infected patients (aCOV) and 44 age-matched healthy controls (Con) were included. Blood of aCOV was sampled at admission (T0), and at day 2 (T2), day 5 (T5), day 10 (T10), and day 30 (T30) while blood of Con was only sampled once. Inter- and intra-group differences were calculated for hematological and hemorheological parameters. Except for mean cellular volume and mean cellular hemoglobin, all blood cell parameters were significantly different between aCOV and Con. During the acute disease state (T0-T5), hematological and hemorheological parameters were highly altered in aCOV; in particular, anemic conditions and increased immune cell response/inflammation, oxidative/nitrosative stress, decreased deformability, as well as increased aggregation, were observed. During treatment and convalescence until T30, almost all abnormal values of aCOV improved towards Con values. During the acute state of the COVID-19 disease, the hematological, as well as the hemorheological system, show fast and potentially pathological changes that might contribute to the progression of the disease, but changes appear to be largely reversible after four weeks. Measuring RBC deformability and aggregation, as well as oxidative stress induction, may be helpful in monitoring critically ill COVID-19 patients.


Asunto(s)
COVID-19 , Hematología , Humanos , Hemorreología , SARS-CoV-2 , Índices de Eritrocitos , Enfermedad Crítica , Agregación Eritrocitaria
9.
Hum Mol Genet ; 28(20): 3339-3354, 2019 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-31334547

RESUMEN

Human dihydrolipoamide dehydrogenase (hLADH, hE3) deficiency (OMIM# 246900) is an often prematurely lethal genetic disease usually caused by inactive or partially inactive hE3 variants. Here we report the crystal structure of wild-type hE3 at an unprecedented high resolution of 1.75 Å and the structures of six disease-causing hE3 variants at resolutions ranging from 1.44 to 2.34 Å. P453L proved to be the most deleterious substitution in structure as aberrations extensively compromised the active site. The most prevalent G194C-hE3 variant primarily exhibited structural alterations close to the substitution site, whereas the nearby cofactor-binding residues were left unperturbed. The G426E substitution mainly interfered with the local charge distribution introducing dynamics to the substitution site in the dimer interface; G194C and G426E both led to minor structural changes. The R460G, R447G and I445M substitutions all perturbed a solvent accessible channel, the so-called H+/H2O channel, leading to the active site. Molecular pathomechanisms of enhanced reactive oxygen species (ROS) generation and impaired binding to multienzyme complexes were also addressed according to the structural data for the relevant mutations. In summary, we present here for the first time a comprehensive study that links three-dimensional structures of disease-causing hE3 variants to residual hLADH activities, altered capacities for ROS generation, compromised affinities for multienzyme complexes and eventually clinical symptoms. Our results may serve as useful starting points for future therapeutic intervention approaches.


Asunto(s)
Dihidrolipoamida Deshidrogenasa/deficiencia , Complejos Multienzimáticos/metabolismo , Dominio Catalítico , Dihidrolipoamida Deshidrogenasa/genética , Humanos , Complejos Multienzimáticos/genética , Mutagénesis Sitio-Dirigida , Mutación/genética , Conformación Proteica , Especies Reactivas de Oxígeno/metabolismo
10.
Purinergic Signal ; 17(4): 693-704, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34403084

RESUMEN

Human ecto-5-nucleotidase (CD73) is involved in purinergic signalling, which influences a diverse range of biological processes. CD73 hydrolyses AMP and is the major control point for the levels of extracellular adenosine. Inhibitors of CD73 thus block the immunosuppressive action of adenosine, a promising approach for cancer immunotherapy. Interestingly, ADP and ATP are competitive inhibitors of CD73, with the most potent small-molecule inhibitors to date being non-hydrolysable ADP analogues. While AMP is the major substrate of the enzyme, CD73 has been reported to hydrolyse other 5'-nucleoside monophosphates. Based on a fragment screening campaign at the BESSY II synchrotron, we present the binding modes of various deoxyribo- and ribonucleoside monophosphates and of four additional fragments binding to the nucleoside binding site of the open form of the enzyme. Kinetic analysis of monophosphate hydrolysis shows that ribonucleotide substrates are favoured over their deoxyribose equivalents with AMP being the best substrate. We characterised the initial step of AMP hydrolysis, the binding mode of AMP to the open conformation of CD73 and compared that to other monophosphate substrates. In addition, the inhibitory activity of various bisphosphonic acid derivatives of nucleoside diphosphates was determined. Although AMPCP remains the most potent inhibitor, replacement of the adenine base with other purines or with pyrimidines increases the Ki value only between twofold and sixfold. On the other hand, these nucleobases offer new opportunities to attach substituents for improved pharmacological properties.


Asunto(s)
5'-Nucleotidasa/metabolismo , Adenosina/metabolismo , Purinas/metabolismo , Nucleótidos de Pirimidina/metabolismo , Transducción de Señal/fisiología , Humanos , Hidrólisis , Unión Proteica , Pliegue de Proteína
11.
Crit Care ; 25(1): 368, 2021 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-34674733

RESUMEN

BACKGROUND: Fever and hypothermia have been observed in septic patients. Their influence on prognosis is subject to ongoing debates. METHODS: We did a secondary analysis of a large clinical dataset from a quality improvement trial. A binary logistic regression model was calculated to assess the association of the thermal response with outcome and a multinomial regression model to assess factors associated with fever or hypothermia. RESULTS: With 6542 analyzable cases we observed a bimodal temperature response characterized by fever or hypothermia, normothermia was rare. Hypothermia and high fever were both associated with higher lactate values. Hypothermia was associated with higher mortality, but this association was reduced after adjustment for other risk factors. Age, community-acquired sepsis, lower BMI and lower outside temperatures were associated with hypothermia while bacteremia and higher procalcitonin values were associated with high fever. CONCLUSIONS: Septic patients show either a hypothermic or a fever response. Whether hypothermia is a maladaptive response, as indicated by the higher mortality in hypothermic patients, or an adaptive response in patients with limited metabolic reserves under colder environmental conditions, remains an open question. Trial registration The original trial whose dataset was analyzed was registered at ClinicalTrials.gov (NCT01187134) on August 23, 2010, the first patient was included on July 1, 2011.


Asunto(s)
Fiebre , Hipotermia , Sepsis , Fiebre/complicaciones , Humanos , Hipotermia/complicaciones , Pronóstico , Sepsis/terapia , Temperatura
12.
Crit Care ; 25(1): 295, 2021 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-34404458

RESUMEN

BACKGROUND: Intensive Care Resources are heavily utilized during the COVID-19 pandemic. However, risk stratification and prediction of SARS-CoV-2 patient clinical outcomes upon ICU admission remain inadequate. This study aimed to develop a machine learning model, based on retrospective & prospective clinical data, to stratify patient risk and predict ICU survival and outcomes. METHODS: A Germany-wide electronic registry was established to pseudonymously collect admission, therapeutic and discharge information of SARS-CoV-2 ICU patients retrospectively and prospectively. Machine learning approaches were evaluated for the accuracy and interpretability of predictions. The Explainable Boosting Machine approach was selected as the most suitable method. Individual, non-linear shape functions for predictive parameters and parameter interactions are reported. RESULTS: 1039 patients were included in the Explainable Boosting Machine model, 596 patients retrospectively collected, and 443 patients prospectively collected. The model for prediction of general ICU outcome was shown to be more reliable to predict "survival". Age, inflammatory and thrombotic activity, and severity of ARDS at ICU admission were shown to be predictive of ICU survival. Patients' age, pulmonary dysfunction and transfer from an external institution were predictors for ECMO therapy. The interaction of patient age with D-dimer levels on admission and creatinine levels with SOFA score without GCS were predictors for renal replacement therapy. CONCLUSIONS: Using Explainable Boosting Machine analysis, we confirmed and weighed previously reported and identified novel predictors for outcome in critically ill COVID-19 patients. Using this strategy, predictive modeling of COVID-19 ICU patient outcomes can be performed overcoming the limitations of linear regression models. Trial registration "ClinicalTrials" (clinicaltrials.gov) under NCT04455451.


Asunto(s)
COVID-19/epidemiología , Enfermedad Crítica/epidemiología , Registros Electrónicos de Salud/estadística & datos numéricos , Unidades de Cuidados Intensivos , Aprendizaje Automático , Adulto , Anciano , COVID-19/terapia , Estudios de Cohortes , Enfermedad Crítica/terapia , Servicio de Urgencia en Hospital , Femenino , Alemania , Humanos , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud
13.
Genet Mol Biol ; 44(2): e20200393, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33877262

RESUMEN

Prolidase Deficiency (PD) is an autosomal recessive rare disorder caused by loss or reduction of prolidase enzymatic activity due to variants in the PEPD gene. PD clinical features vary among affected individuals: skin ulcerations, recurrent infections, and developmental delay are common. In this study, we describe a 16-year-old boy with a mild PD phenotype comprising chronic eczema, recurrent infections and elevated IgE. Whole exome sequencing analysis revealed three PEPD variants: c.575T>C p.(Leu192Pro) inherited from the mother, and c.692_694del p.(Tyr231del) and c.1409G>A p.(Arg470His), both inherited from the father. The variant p.(Tyr231del) has been previously characterized by high-resolution X-ray structure analysis as altering protein dynamics/flexibility. In order to study the effects of the other two prolidase variants, we performed site directed mutagenesis purification and crystallization studies. A high-resolution X-ray structure could only be obtained for the p.(Arg470His) variant, which showed no significant structural differences in comparison to WT prolidase. On the other hand, the p.(Leu192Pro) variant led to significant protein destabilization. Hence, we conclude that the maternal p.(Leu192Pro) variant was likely causally associated with the proband´s disease, together with the known pathogenic paternal variant p.(Tyr231del). Our results demonstrated the utility of exome sequencing to perform diagnosis in PD cases with mild phenotype.

14.
Scand J Immunol ; 91(2): e12837, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31622512

RESUMEN

After severe trauma, the resulting excessive inflammatory response is countered by compensatory anti-inflammatory mechanisms. The systemic inflammatory response to trauma enhanced by inappropriately timed surgical second hits may be detrimental for the patient. On the other hand, overwhelming anti-inflammatory mechanisms may put patients at increased risk from secondary local and systemic infections. The ensuing sepsis and organ dysfunction due to immune dysregulation remain the leading causes of death after injury. To date, there are no clinically applicable techniques to monitor the pro-/anti-inflammatory immune status of the patients and the remaining ability to react to microbial stimuli. Therefore, in the present study, we used a highly standardized and easy-to-use system to draw peripheral whole blood from polytraumatized patients (ISS ≥ 32, n = 7) and to challenge it with bacterial lipopolysaccharide. Secreted cytokines were compared with those in samples from healthy volunteers. We observed a significant decrease in the release of monocyte-derived mediators. Surprisingly, we detected stable or even increased concentrations of cytokines related to T cell maturation and function. For clinical practicability, we reduced the incubation time before supernatants were collected. Even after an abbreviated stimulation period, a stable release of almost all analysed parameters in patient blood could be detected. In conclusion, the data are indicative of a clinically well-applicable approach to monitor the immune status in severely injured patients in a short time. This may be used to optimize the timing of necessary surgical interventions to avoid a boost of proinflammation and reduce risk of secondary infections.


Asunto(s)
Monitorización Inmunológica/métodos , Traumatismo Múltiple/diagnóstico , Adulto , Células Cultivadas , Progresión de la Enfermedad , Femenino , Humanos , Lipopolisacáridos/inmunología , Masculino , Persona de Mediana Edad , Proyectos Piloto
15.
Inorg Chem ; 59(1): 350-359, 2020 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-31820946

RESUMEN

In situ formation of imine-based organic linkers facilitates the formation of metal-organic frameworks (MOFs), in particular if linker solubility hampers the direct synthesis. The reaction of ZrCl4 with 4-formylbenzoic acid or 4-formyl-3-hydroxybenzoic acid as the aldehyde source and 4-aminobenzoic acid as the amine source is shown to produce zirconium MOFs isoreticular to UiO-66 (PCN-161 and a novel DUT-133, [Zr6O4(OH)4(C15H9NO5)6], respectively). A similar reaction with p-phenylenediamine as the amine-containing building block gave 2-fold interpenetrated framework (PCN-164). Detailed characterization, including single crystal and powder X-ray diffraction, water stability tests, thermal stability, and in situ 1H and 13C NMR were performed to elucidate the formation mechanism of zirconium MOFs containing imine-based linkers. The resulting zirconium MOFs were evaluated as potential materials for CO2 capture and as ethylene oligomerization catalysts with anchored nickel as the active species.

16.
J Synchrotron Radiat ; 26(Pt 2): 393-405, 2019 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-30855248

RESUMEN

MXCuBE2 is the second-generation evolution of the MXCuBE beamline control software, initially developed and used at ESRF - the European Synchrotron. MXCuBE2 extends, in an intuitive graphical user interface (GUI), the functionalities and data collection methods available to users while keeping all previously available features and allowing for the straightforward incorporation of ongoing and future developments. MXCuBE2 introduces an extended abstraction layer that allows easy interfacing of any kind of macromolecular crystallography (MX) hardware component, whether this is a diffractometer, sample changer, detector or optical element. MXCuBE2 also works in strong synergy with the ISPyB Laboratory Information Management System, accessing the list of samples available for a particular experimental session and associating, either from instructions contained in ISPyB or from user input via the MXCuBE2 GUI, different data collection types to them. The development of MXCuBE2 forms the core of a fruitful collaboration which brings together several European synchrotrons and a software development factory and, as such, defines a new paradigm for the development of beamline control platforms for the European MX user community.

17.
J Immunol ; 198(12): 4846-4854, 2017 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-28490576

RESUMEN

During sepsis, excessive activation of the complement system with generation of the anaphylatoxin C5a results in profound disturbances in crucial neutrophil functions. Moreover, because neutrophil activity is highly dependent on intracellular pH (pHi), we propose a direct mechanistic link between complement activation and neutrophil pHi In this article, we demonstrate that in vitro exposure of human neutrophils to C5a significantly increased pHi by selective activation of the sodium/hydrogen exchanger. Upstream signaling of C5a-mediated intracellular alkalinization was dependent on C5aR1, intracellular calcium, protein kinase C, and calmodulin, and downstream signaling regulated the release of antibacterial myeloperoxidase and lactoferrin. Notably, the pH shift caused by C5a increased the glucose uptake and activated glycolytic flux in neutrophils, resulting in a significant release of lactate. Furthermore, C5a induced acidification of the extracellular micromilieu. In experimental murine sepsis, pHi of blood neutrophils was analogously alkalinized, which could be normalized by C5aR1 inhibition. In the clinical setting of sepsis, neutrophils from patients with septic shock likewise exhibited a significantly increased pHi These data suggest a novel role for the anaphylatoxin C5a as a master switch of the delicate pHi balance in neutrophils resulting in profound inflammatory and metabolic changes that contribute to hyperlactatemia during sepsis.


Asunto(s)
Activación de Complemento , Complemento C5a/metabolismo , Activación Neutrófila , Neutrófilos/inmunología , Sepsis/inmunología , Sepsis/metabolismo , Animales , Antiácidos/farmacología , Calcio/metabolismo , Calmodulina/metabolismo , Complemento C5a/inmunología , Glucosa/metabolismo , Humanos , Concentración de Iones de Hidrógeno , Lactatos/metabolismo , Lactoferrina , Ratones , Neutrófilos/química , Neutrófilos/efectos de los fármacos , Neutrófilos/metabolismo , Peroxidasa/metabolismo , Proteína Quinasa C/inmunología , Proteína Quinasa C/metabolismo , Receptor de Anafilatoxina C5a/metabolismo , Transducción de Señal
18.
JAMA ; 322(17): 1692-1704, 2019 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-31577037

RESUMEN

IMPORTANCE: End-of-life decisions occur daily in intensive care units (ICUs) around the world, and these practices could change over time. OBJECTIVE: To determine the changes in end-of-life practices in European ICUs after 16 years. DESIGN, SETTING, AND PARTICIPANTS: Ethicus-2 was a prospective observational study of 22 European ICUs previously included in the Ethicus-1 study (1999-2000). During a self-selected continuous 6-month period at each ICU, consecutive patients who died or had any limitation of life-sustaining therapy from September 2015 until October 2016 were included. Patients were followed up until death or until 2 months after the first treatment limitation decision. EXPOSURES: Comparison between the 1999-2000 cohort vs 2015-2016 cohort. MAIN OUTCOMES AND MEASURES: End-of-life outcomes were classified into 5 mutually exclusive categories (withholding of life-prolonging therapy, withdrawing of life-prolonging therapy, active shortening of the dying process, failed cardiopulmonary resuscitation [CPR], brain death). The primary outcome was whether patients received any treatment limitations (withholding or withdrawing of life-prolonging therapy or shortening of the dying process). Outcomes were determined by senior intensivists. RESULTS: Of 13 625 patients admitted to participating ICUs during the 2015-2016 study period, 1785 (13.1%) died or had limitations of life-prolonging therapies and were included in the study. Compared with the patients included in the 1999-2000 cohort (n = 2807), the patients in 2015-2016 cohort were significantly older (median age, 70 years [interquartile range {IQR}, 59-79] vs 67 years [IQR, 54-75]; P < .001) and the proportion of female patients was similar (39.6% vs 38.7%; P = .58). Significantly more treatment limitations occurred in the 2015-2016 cohort compared with the 1999-2000 cohort (1601 [89.7%] vs 1918 [68.3%]; difference, 21.4% [95% CI, 19.2% to 23.6%]; P < .001), with more withholding of life-prolonging therapy (892 [50.0%] vs 1143 [40.7%]; difference, 9.3% [95% CI, 6.4% to 12.3%]; P < .001), more withdrawing of life-prolonging therapy (692 [38.8%] vs 695 [24.8%]; difference, 14.0% [95% CI, 11.2% to 16.8%]; P < .001), less failed CPR (110 [6.2%] vs 628 [22.4%]; difference, -16.2% [95% CI, -18.1% to -14.3%]; P < .001), less brain death (74 [4.1%] vs 261 [9.3%]; difference, -5.2% [95% CI, -6.6% to -3.8%]; P < .001) and less active shortening of the dying process (17 [1.0%] vs 80 [2.9%]; difference, -1.9% [95% CI, -2.7% to -1.1%]; P < .001). CONCLUSIONS AND RELEVANCE: Among patients who had treatment limitations or died in 22 European ICUs in 2015-2016, compared with data reported from the same ICUs in 1999-2000, limitations in life-prolonging therapies occurred significantly more frequently and death without limitations in life-prolonging therapies occurred significantly less frequently. These findings suggest a shift in end-of-life practices in European ICUs, but the study is limited in that it excluded patients who survived ICU hospitalization without treatment limitations.

19.
Artículo en Alemán | MEDLINE | ID: mdl-30620952

RESUMEN

Sepsis is a common disease in intensive care units worldwide, which is associated with relevant morbidity and mortality. Although massive research efforts have been made for decades, there is no specific therapy for sepsis to date. Decisive in the treatment of sepsis is the early diagnosis, because the outcome of the treated patients can be significantly improved by early elimination of the infection focus, the fastest possible administration of a broad, calculated antibiosis as well as the stabilization of the hemodynamic situation. A definition of the clinical picture of sepsis with high diagnostic sensitivity and specificity is therefore indispensable. This article describes the previously and the currently available definition of sepsis and gives an overview of the epidemiology of this disease.


Asunto(s)
Sepsis/clasificación , Sepsis/epidemiología , Cuidados Críticos , Humanos , Insuficiencia Multiorgánica/diagnóstico , Insuficiencia Multiorgánica/etiología , Terminología como Asunto
20.
Hum Mol Genet ; 25(21): 4717­4725, 2016 08 29.
Artículo en Inglés | MEDLINE | ID: mdl-27577872

RESUMEN

A recent publication by Seng et al. in this journal reports the crystallographic structure of refolded, full-length SMN protein and two disease-relevant derivatives thereof. Here, we would like to suggest that at least two of the structures reported in that study are incorrect. We present evidence that one of the associated crystallographic datasets is derived from a crystal of the bacterial Sm-like protein Hfq and that a second dataset is derived from a crystal of the bacterial Gab protein. Both proteins are frequent contaminants of bacterially overexpressed proteins which might have been co-purified during metal affinity chromatography. A third structure presented in the Seng et al. paper cannot be examined further because neither the atomic coordinates, nor the diffraction intensities were made publicly available. The Tudor domain protein SMN has been shown to be a component of the SMN complex, which mediates the assembly of RNA-protein complexes of uridine-rich small nuclear ribonucleoproteins (UsnRNPs). Importantly, this activity is reduced in SMA patients, raising the possibility that the aetiology of SMA is linked to RNA metabolism. Structural studies on diverse components of the SMN complex, including fragments of SMN itself have contributed greatly to our understanding of the cellular UsnRNP assembly machinery. Yet full-length SMN has so far evaded structural elucidation. The Seng et al. study claimed to have closed this gap, but based on the results presented here, the only conclusion that can be drawn is that the Seng et al. study is largely invalid and should be retracted from the literature.

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