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Lysozyme is an important component of the innate immune system. It functions by hydrolyzing the peptidoglycan (PG) layer of bacteria. The human pathogen Listeria monocytogenes is intrinsically lysozyme resistant. The peptidoglycan N-deacetylase PgdA and O-acetyltransferase OatA are two known factors contributing to its lysozyme resistance. Furthermore, it was shown that the absence of components of an ABC transporter, referred to here as EslABC, leads to reduced lysozyme resistance. How its activity is linked to lysozyme resistance is still unknown. To investigate this further, a strain with a deletion in eslB, coding for a membrane component of the ABC transporter, was constructed in L. monocytogenes strain 10403S. The eslB mutant showed a 40-fold reduction in the MIC to lysozyme. Analysis of the PG structure revealed that the eslB mutant produced PG with reduced levels of O-acetylation. Using growth and autolysis assays, we showed that the absence of EslB manifests in a growth defect in media containing high concentrations of sugars and increased endogenous cell lysis. A thinner PG layer produced by the eslB mutant under these growth conditions might explain these phenotypes. Furthermore, the eslB mutant had a noticeable cell division defect and formed elongated cells. Microscopy analysis revealed that an early cell division protein still localized in the eslB mutant, indicating that a downstream process is perturbed. Based on our results, we hypothesize that EslB affects the biosynthesis and modification of the cell wall in L. monocytogenes and is thus important for the maintenance of cell wall integrity.IMPORTANCE The ABC transporter EslABC is associated with the intrinsic lysozyme resistance of Listeria monocytogenes However, the exact role of the transporter in this process and in the physiology of L. monocytogenes is unknown. Using different assays to characterize an eslB deletion strain, we found that the absence of EslB affects not only lysozyme resistance but also endogenous cell lysis, cell wall biosynthesis, cell division, and the ability of the bacterium to grow in media containing high concentrations of sugars. Our results indicate that EslB is, by means of a yet-unknown mechanism, an important determinant for cell wall integrity in L. monocytogenes.
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Proteínas Bacterianas/metabolismo , Pared Celular/metabolismo , Listeria monocytogenes/metabolismo , Proteínas Bacterianas/genética , Eliminación de Gen , Regulación de la Expresión Génica , Listeria monocytogenes/patogenicidad , Muramidasa/metabolismo , Peptidoglicano/química , Peptidoglicano/metabolismo , VirulenciaRESUMEN
Patients with rare diseases often receive insufficient medical care. The European Reference Networks (ERNs) were initiated by the European Union to improve healthcare for patients with rare and complex diseases within Europe. The Reference Network on Hepatological Diseases (ERN RARE-LIVER), which consists of hepatological centres, scientific societies and numerous patient organizations, is one of 24 ERNs. The aim of ERN RARE-LIVER is high-quality healthcare for patients suffering from rare liver diseases, regardless of their place of residence. Standardization of treatment, coordination of research projects as well as training and teaching of patients, patient representatives and healthcare professionals are means to reach this goal. Virtual case discussions are offered via a web-based platform (Clinical Patient Management System), in which experts from the ERNs advise treating physicians on the diagnosis and therapy of rare diseases.
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Atención a la Salud , Enfermedades Raras , Europa (Continente) , Personal de Salud , Humanos , Enfermedades Raras/diagnóstico , Enfermedades Raras/terapiaRESUMEN
AIMS: Drug-induced liver injury (DILI) is a heterogenous entity leading to liver damage. We have analysed the frequency, biochemical and histological patterns and clinical courses of DILI cases due to metamizole at our tertiary care centre in Hamburg, Germany. METHODS: Consecutive patients with DILI who presented to our clinic were analysed retrospectively. Causes of acute hepatitis other than DILI were excluded. RESULTS: In total, 154 DILI cases were admitted to our centre from 2008 to 2017. After phenprocoumon, metamizole was the second most frequent putative agent causing DILI (23 of all 154 DILI cases, 14,9%). The biochemical pattern on admission of metamizole-induced DILI cases was hepatocellular with median levels of alanine transaminase (779 U/L, 64-3532 U/L) by far exceeding median alkaline phosphatase levels (131 U/L, 42-578 U/L). In 17 of the 23 cases (74%) liver biopsy was performed. Moderate to severe inflammatory histological activity and severe centrilobular necrosis (>30%) was present in 76.5 and 35.3%, respectively. Metamizole was involved in 2 DILI cases progressing to acute liver failure, then receiving liver transplantation and still alive at time of assessment. Our data were supported by re-exposure in 4 patients. Furthermore, a database search for metamizole-induced liver injury in the European Medicines Agency's database identified about 300 reports on suspected metamizole-induced DILI in Europe. CONCLUSION: Elevation of liver enzymes or acute liver failure are not mentioned in the German drug label of metamizole as potential side effects. Our study reveals that in Germany and Europe, metamizole is a frequent and underrated agent causing DILI.
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Enfermedad Hepática Inducida por Sustancias y Drogas , Dipirona , Enfermedad Hepática Inducida por Sustancias y Drogas/epidemiología , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Dipirona/efectos adversos , Europa (Continente) , Alemania/epidemiología , Humanos , Hígado , Estudios RetrospectivosRESUMEN
The soil bacterium Bacillus subtilis can get into contact with growth-inhibiting substances, which may be of anthropogenic origin. Glyphosate is such a substance serving as a nonselective herbicide. Glyphosate specifically inhibits the 5-enolpyruvyl-shikimate-3-phosphate (EPSP) synthase, which generates an essential precursor for de novo synthesis of aromatic amino acids in plants, fungi, bacteria and archaea. Inhibition of the EPSP synthase by glyphosate results in depletion of the cellular levels of aromatic amino acids unless the environment provides them. Here, we have assessed the potential of B. subtilis to adapt to glyphosate at the genome level. In contrast to Escherichia coli, which evolves glyphosate resistance by elevating the production and decreasing the glyphosate sensitivity of the EPSP synthase, B. subtilis primarily inactivates the gltT gene encoding the high-affinity glutamate/aspartate symporter GltT. Further adaptation of the gltT mutants to glyphosate led to the inactivation of the gltP gene encoding the glutamate transporter GltP. Metabolome analyses confirmed that GltT is the major entryway of glyphosate into B. subtilis. GltP, the GltT homologue of E. coli also transports glyphosate into B. subtilis. Finally, we found that GltT is involved in uptake of the herbicide glufosinate, which inhibits the glutamine synthetase.
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3-Fosfoshikimato 1-Carboxiviniltransferasa/metabolismo , Adaptación Fisiológica/genética , Genoma Bacteriano/genética , Glicina/análogos & derivados , Sistemas de Transporte de Aminoácidos Acídicos/genética , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Activación Enzimática/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Escherichia coli/genética , Glicina/metabolismo , Glicina/toxicidad , Herbicidas/metabolismo , Herbicidas/toxicidad , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/metabolismo , GlifosatoRESUMEN
Objectives: Primary biliary cholangitis (PBC) is a chronic inflammatory disease of the small intrahepatic bile ducts disproportionally affecting women. Timely diagnosis and treatment can often prevent progression to liver cirrhosis. We hypothesized PBC diagnosis in male patients is delayed and prognosis impaired. We, therefore, conducted a case-control study and compared clinical and prognostic features among male and female patients with PBC.Materials and methods: 49 male patients with PBC treated at a German tertiary care center between 2006 and 2017 were identified and compared to 98 age-matched female controls. Prospectively collected clinical/biochemical data were analyzed retrospectively. Liver biopsies were scored in a blinded fashion. Prognostic parameters were calculated using established prognostic scores (GLOBE, PBC-UKE). Statistical analysis was performed using Mann-Whitney test and Fisher´s exact test.Results: At PBC diagnosis, male patients reported significantly less PBC-associated symptoms as compared to female controls (34 versus 71%, p < .01). Compared to female patients, median time from onset of PBC-related symptoms and/or first reported elevated cholestatic biochemical parameters to PBC diagnosis was significantly increased in men (36 versus 12 months, p = .02). In addition, male patients underwent liver biopsy to establish PBC diagnosis more frequently, tended to show more advanced fibrosis and showed significantly poorer prognostic PBC score results. Hepatocellular carcinoma was only observed in male patients (n = 3).Conclusions: When compared to women, men with PBC suffer from less PBC-related symptoms, receive PBC diagnosis delayed and have a worse prognosis. Despite its rarity, the diagnosis of PBC should be considered in men with elevated cholestatic parameters.
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Conductos Biliares Intrahepáticos , Colangitis/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Factores SexualesRESUMEN
OBJECTIVE: The controlled attenuation parameter (CAP) measured by transient elastography allows for the noninvasive assessment of hepatic steatosis. However, discrepant results between CAP values and histological evaluation have been reported in particular with high CAP values. We therefore investigated the diagnostic validity of high CAP measurements. METHODS: Forty patients with liver disease and CAP measurements >â300âdB/m that underwent ultrasound-guided or minilaparoscopic liver biopsy were retrospectively enrolled. CAP values were compared with the respective histological and macroscopic evaluation and correlated with clinical parameters. RESULTS: CAP values >â300âdB/m had an 87.5â% specificity for detection of hepatic steatosis but failed to discriminate between steatosis grade S1â-âS3. Discordant results, defined as a discrepancy of at least 2 steatosis grades between transient elastography and liver biopsy, were observed in 40â% of cases. The interquartile range (IQR) of CAP was confirmed as a predictor of discrepant findings. Macroscopic evaluation as part of minilaparoscopy detected hepatic steatosis in 74â% of patients with histological grade S2â-âS3 in contrast to only 10â% classified as histological grade S0â-âS1. CONCLUSION: High CAP measurements need to be interpreted with care and with regard to clinical parameters, in particular when high IQR values are registered.
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Diagnóstico por Imagen de Elasticidad/métodos , Hígado Graso/patología , Hígado/patología , Enfermedad del Hígado Graso no Alcohólico/patología , Biopsia , Humanos , Valor Predictivo de las Pruebas , Curva ROC , Estudios Retrospectivos , Sensibilidad y EspecificidadRESUMEN
In 2015, more than 13â000 people died due to the consequences of liver cirrhosis in Germany. Frequently, relevant liver fibrosis is diagnosed by non-invasive methods (e.âg., ultrasound-based measurement of liver stiffness) already in the compensated stage. Following diagnosis of liver fibrosis, a thorough investigation of the underlying chronic liver disease and effective treatment are important to prevent progression to decompensated cirrhosis. Since morbidity and mortality dramatically increase in the decompensated stage (patients may present with jaundice, ascites, hepatic encephalopathy, gastrointestinal bleeding) with an upsurge in 1-year-mortality from 1â-â3.4â% to 20â-â57â%, prophylactic measures to prevent decompensation are indicated. Based on a risk stratification, these measures include propranolol or carvedilol as non-selective betablockers, as well as endoscopic band ligations as primary prophylaxis to prevent variceal bleeding. Because of the high risk for malignant transformation (2â-â8â% per year depending on the underlying etiology), surveillance by liver ultrasound every six months is essential to detect liver cancer in an early stage and to facilitate curative therapy. Currently under debate is the administration of antibiotics to prevent bacterial infections, which commonly trigger acute decompensation. To this regard, studies are not convincing and the risk to induce drug resistance has to be observed. However, health care providers should check the vaccination status and recommend missing vaccinations. The management of compensated liver cirrhosis also includes counseling and potentially also a drug therapy to prevent osteoporosis and muscle wasting. In this review, we will discuss specific prophylactic measures in the management of compensated liver cirrhosis based on the pathophysiological background and central clinical studies. If a patient decompensates despite these prophylactic measures (approximately 15â% of patients with liver cirrhosis per year), liver transplantation has to be discussed as definitive therapy (especially in patients with MELD >â15).
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Carvedilol/administración & dosificación , Várices Esofágicas y Gástricas/prevención & control , Hemorragia Gastrointestinal/prevención & control , Cirrosis Hepática/diagnóstico , Cirrosis Hepática/terapia , Propranolol/administración & dosificación , Alemania , Encefalopatía Hepática , Humanos , Cirrosis Hepática/fisiopatologíaRESUMEN
Idiosyncratic drug-induced liver injury (DILI) and hepatic injury due to herbal and dietary supplements (HDS) can adapt clinical characteristics of autoimmune hepatitis (AIH), such as the appearance of autoantibodies and infiltration of the liver by immune competent cells. To describe these cases of DILI/HDS, the poorly-defined term "autoimmune(-like)" DILI/HDS came up. It is uncertain if these cases represent a subgroup of DILI/HDS with distinct pathomechanistic and prognostic features different from "classical" DILI/HDS. Besides, due to the overlap of clinical characteristics of "immune-mediated" DILI/HDS and AIH, both entities are not easy to differentiate. However, the demarcation is important, especially with regard to treatment: AIH requires long-term, mostly lifelong immunosuppression, whereas DILI/HDS does not. Only through exact diagnostic evaluation, exclusion of differential diagnoses and prolonged follow-up can the correct diagnosis reliably be made. Molecular mechanisms have not been analysed for the subgroup of "autoimmune(-like)" DILI/HDS yet. However, several pathogenetic checkpoints of DILI/HDS in general and AIH are shared. An analysis of these shared mechanisms might hint at relevant molecular processes of "autoimmune(-like)" DILI/HDS.
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Enfermedad Hepática Inducida por Sustancias y Drogas/inmunología , Suplementos Dietéticos/efectos adversos , Hepatitis Autoinmune/inmunología , Hígado/efectos de los fármacos , Hígado/lesiones , Fitoterapia/efectos adversos , Autoanticuerpos , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Diagnóstico Diferencial , Hepatitis Autoinmune/patología , Medicina de Hierbas , Humanos , Hígado/inmunologíaRESUMEN
The foodborne pathogen Listeria monocytogenes can grow in a wide range of environmental conditions. For the study of the physiology of this organism, several chemically defined media have been developed over the past decades. Here, we examined the ability of L. monocytogenes wildtype strains EGD-e and 10403S to grow under salt and pH stress in Listeria synthetic medium (LSM). Furthermore, we determined that a wide range of carbon sources could support the growth of both wildtype strains in LSM. However, for hexose phosphate sugars such as glucose-1-phosphate, both L. monocytogenes strains need to be pre-grown under conditions, where the major virulence regulator PrfA is active. In addition, growth of both L. monocytogenes strains was observed when LSM was supplemented with the amino acid sugar N-acetylmannosamine (ManNAc). We were able to show that some of the proteins encoded in the operon lmo2795-nanE, such as the ManNAc-6-phosphate epimerase NanE, are required for growth in the presence of ManNAc. The first gene of the operon, lmo2795, encodes a transcriptional regulator of the RpiR family. Using electrophoretic mobility shift assays and quantitative real-time PCR analysis, we were able to show that Lmo2795 binds to the promoter region of the operon lmo2795-nanE and activates its expression.
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Listeria monocytogenes , Listeria , Listeria monocytogenes/genética , Listeria/genética , Listeria/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Virulencia/genética , Operón , Regulación Bacteriana de la Expresión GénicaRESUMEN
Listeria monocytogenes is ubiquitously found in nature and can easily enter food-processing facilities due to contaminations of raw materials. Several countermeasures are used to combat contamination of food products, for instance, the use of disinfectants that contain quaternary ammonium compounds, such as benzalkonium chloride (BAC) and cetyltrimethylammonium bromide (CTAB). In this study, we assessed the potential of the commonly used wild-type strain EGD-e to adapt to BAC and CTAB under laboratory growth conditions. All BAC-tolerant suppressors exclusively carried mutations in fepR, encoding a TetR-like transcriptional regulator, or its promoter region, likely resulting in the overproduction of the efflux pump FepA. In contrast, CTAB tolerance was associated with mutations in sugR, which regulates the expression of the efflux pumps SugE1 and SugE2. L. monocytogenes strains lacking either FepA or SugE1/2 could still acquire tolerance toward BAC and CTAB. Genomic analysis revealed that the overproduction of the remaining efflux system could compensate for the deleted one, and even in the absence of both efflux systems, tolerant strains could be isolated, which all carried mutations in the diacylglycerol kinase-encoding gene lmo1753 (dgkB). DgkB converts diacylglycerol to phosphatidic acid, which is subsequently reused for the synthesis of phospholipids, suggesting that alterations in membrane composition could be the third adaptation mechanism. IMPORTANCE Survival and proliferation of Listeria monocytogenes in the food industry are ongoing concerns, and while there are various countermeasures to combat contamination of food products, the pathogen still successfully manages to withstand the harsh conditions present in food-processing facilities, resulting in reoccurring outbreaks, subsequent infection, and disease. To counteract the spread of L. monocytogenes, it is crucial to understand and elucidate the underlying mechanism that permits their successful evasion. We present various adaptation mechanisms of L. monocytogenes to withstand two important quaternary ammonium compounds.
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The bacterial cell wall is composed of a thick layer of peptidoglycan and cell wall polymers, which are either embedded in the membrane or linked to the peptidoglycan backbone and referred to as lipoteichoic acid (LTA) and wall teichoic acid (WTA), respectively. Modifications of the peptidoglycan or WTA backbone can alter the susceptibility of the bacterial cell towards cationic antimicrobials and lysozyme. The human pathogen Listeria monocytogenes is intrinsically resistant towards lysozyme, mainly due to deacetylation and O-acetylation of the peptidoglycan backbone via PgdA and OatA. Recent studies identified additional factors, which contribute to the lysozyme resistance of this pathogen. One of these is the predicted ABC transporter, EslABC. An eslB mutant is hyper-sensitive towards lysozyme, likely due to the production of thinner and less O-acetylated peptidoglycan. Using a suppressor screen, we show here that suppression of eslB phenotypes could be achieved by enhancing peptidoglycan biosynthesis, reducing peptidoglycan hydrolysis or alterations in WTA biosynthesis and modification. The lack of EslB also leads to a higher negative surface charge, which likely stimulates the activity of peptidoglycan hydrolases and lysozyme. Based on our results, we hypothesize that the portion of cell surface exposed WTA is increased in the eslB mutant due to the thinner peptidoglycan layer and that latter one could be caused by an impairment in UDP-N-acetylglucosamine (UDP-GlcNAc) production or distribution.
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With regard to potential applications of genomic selection in small numbered breeds, we evaluated genomic models and focused on potential candidate gene annotations for weight and meat quality traits in the local Rotes Höhenvieh (RHV) breed. Traits included 6,003 birth weights (BWT), 5,719 200 d-weights (200dw), 4,594 365 d-weights (365dw), and 547 records for intramuscular fat content (IMF). A total of 581,304 SNP from 370 genotyped cattle with phenotypic records were included in genomic analyses. Model evaluations focused on single- and multiple-trait models with direct and with direct and maternal genetic effects. Genetic relationship matrices were based on pedigree (A-matrix), SNP markers (G-matrix), or both (H-matrix). Genome-wide association studies (GWASs) were carried out using linear mixed models to identify potential candidate genes for the traits of interest. De-regressed proofs (DRP) for direct and maternal genetic components were used as pseudo-phenotypes in the GWAS. Accuracies of direct breeding values were higher from models based on G or on H compared to A. Highest accuracies (> 0.89) were obtained for IMF with multiple-trait models using the G-matrix. Direct heritabilities with maternal genetic effects ranged from 0.62 to 0.66 for BWT, from 0.45 to 0.55 for 200dW, from 0.40 to 0.44 for 365dW, and from 0.48 to 0.75 for IMF. Maternal heritabilities for BWT, 200dW, and 365dW were in a narrow range from 0.21 to 0.24, 0.24 to 0.27, and 0.21 to 0.25, respectively, and from 0.25 to 0.65 for IMF. Direct genetic correlations among body weight traits were positive and favorable, and very similar from different models but showed a stronger variation with 0.31 (A), -0.13 (G), and 0.45 (H) between BWT and IMF. In gene annotations, we identified 6, 3, 1, and 6 potential candidate genes for direct genetic effect on BWT, 200dW, 365dW, and IMF traits, respectively. Regarding maternal genetic effects, four (SHROOM3, ZNF609, PECAM1, and TEX2) and two (TMEM182 and SEC11A) genes were detected as potential candidate genes for BWT and 365dW, respectively. Potential candidate genes for maternal effect on IMF were GRHL2, FGA, FGB, and CTNNA3. As the most important finding from a practical breeding perspective, a small number of genotyped RHV cattle enabled accurate breeding values for high heritability IMF.
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Diastolic dysfunction in heart failure with preserved ejection fraction (HFpEF) is characterised by increased left ventricular stiffness and impaired active relaxation. Underpinning pathomechanisms are incompletely understood. Cardiac hypertrophy and end stage heart disease are associated with alterations in the cardiac microtubule (MT) network. Increased amounts and modifications of α-tubulin associate with myocardial stiffness. MT alterations in HFpEF have not been analysed yet. Using ZSF1 obese rats (O-ZSF1), a validated HFpEF model, we characterised MT-modifying enzymes, quantity and tyrosination/detyrosination pattern of α-tubulin at 20 and 32 weeks of age. In the left ventricle of O-ZSF1, α-tubulin concentration (20 weeks: 1.5-fold, p = 0.019; 32 weeks: 1.7-fold, p = 0.042) and detyrosination levels (20 weeks: 1.4-fold, p = 0.013; 32 weeks: 1.3-fold, p = 0.074) were increased compared to lean ZSF1 rats. Tyrosination/α-tubulin ratio was lower in O-ZSF1 (20 weeks: 0.8-fold, p = 0.020; 32 weeks: 0.7-fold, p = 0.052). Expression of α-tubulin modifying enzymes was comparable. These results reveal new alterations in the left ventricle in HFpEF that are detectable during early (20 weeks) and late (32 weeks) progression. We suppose that these alterations contribute to diastolic dysfunction in HFpEF and that reestablishment of MT homeostasis might represent a new target for pharmacological interventions.
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Insuficiencia Cardíaca , Animales , Modelos Animales de Enfermedad , Miocardio/metabolismo , Ratas , Volumen Sistólico , Tubulina (Proteína)/metabolismoRESUMEN
ATP-binding cassette (ABC) transporters are usually involved in the translocation of their cognate substrates, which is driven by ATP hydrolysis. Typically, these transporters are required for the import or export of a wide range of substrates such as sugars, ions and complex organic molecules. ABC exporters can also be involved in the export of toxic compounds such as antibiotics. However, recent studies revealed alternative detoxification mechanisms of ABC transporters. For instance, the ABC transporter BceAB of Bacillus subtilis seems to confer resistance to bacitracin via target protection. In addition, several transporters with functions other than substrate export or import have been identified in the past. Here, we provide an overview of recent findings on ABC transporters of the Gram-positive organisms B. subtilis and Listeria monocytogenes with transport or regulatory functions affecting antibiotic resistance, cell wall biosynthesis, cell division and sporulation.
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Bacillus subtilis develops genetic competence for the uptake of foreign DNA when cells enter stationary phase and a high cell density is reached. These signals are integrated by the competence transcription factor ComK, which is subject to transcriptional, post-transcriptional and post-translational regulation. Many proteins are involved in the development of competence, both to control ComK activity and to mediate DNA uptake. However, for many proteins, the precise function they play in competence development is unknown. In this study, we assessed whether proteins required for genetic transformation play a role in the activation of ComK or rather act downstream of competence gene expression. While these possibilities could be distinguished for most of the tested factors, we assume that two proteins, PNPase and the transcription factor YtrA, are required both for full ComK activity and for the downstream processes of DNA uptake and integration. Further analyses of the role of the transcription factor YtrA for the competence development revealed that the overexpression of the YtrBCDEF ABC transporter in the ytrA mutant causes the loss of genetic competence. Moreover, overexpression of this ABC transporter also affects biofilm formation. Since the ytrGABCDEF operon is naturally induced by cell wall-targeting antibiotics, we tested the cell wall properties upon overexpression of the ABC transporter and observed an increased thickness of the cell wall. The composition and properties of the cell wall are important for competence development and biofilm formation, suggesting that the observed phenotypes are the result of the increased cell wall thickness as an outcome of YtrBCDEF overexpression.
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BACKGROUND: TGFß1 is a growth factor that plays a major role in the remodeling process of the heart by inducing cardiomyocyte dysfunction and apoptosis, as well as fibrosis thereby restricting heart function. TGFß1 mediates its effect via the TGFß receptor I (ALK5) and the activation of SMAD transcription factors, but TGFß1 is also known as activator of phosphoinositide-3-kinase (PI3K) via the non-SMAD signaling pathway. The aim of this study was to investigate whether PI3K is also involved in TGFß1-induced cardiomyocytes apoptosis and contractile dysfunction. METHODS AND RESULTS: Incubation of isolated ventricular cardiomyocytes with TGFß1 resulted in impaired contractile function. Pre-incubation of cells with the PI3K inhibitor Ly294002 or the ALK5 inhibitor SB431542 attenuated the decreased cell shortening in TGFß1-stimulated cells. Additionally, TGFß-induced apoptosis was significantly reduced by the PI3K inhibitor Ly294002. Administration of a PI3Kγ-specific inhibitor AS605240 abolished the TGFß effect on apoptosis and cell shortening. This was also confirmed in cardiomyocytes from PI3Kγ KO mice. Induction of SMAD binding activity and the TGFß target gene collagen 1 could be blocked by the PI3K inhibitor Ly294002, but not by the specific PI3Kγ inhibitor AS605240. CONCLUSIONS: TGFß1-induced SMAD activation, cardiomyocyte apoptosis, and impaired cell shortening are mediated via both, the ALK5 receptor and PI3K, in adult cardiomyocytes. PI3Kγ specifically contributes to apoptosis induction and impairment of contractile function independent of SMAD signaling.
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BACKGROUND: Head and neck squamous cell cancer (HNSCC) is one of the most common tumors worldwide and there is an enormous need for innovative therapy approaches. Several recent studies suggest tumor entity specific roles of glycogen synthase kinase 3 (GSK3) in different human cancers, acting as tumor suppressor or as tumor promoter. Here we describe the role of GSK3 with respect to different parameters within HNSCC progression. METHODS: Base line expression and activity profiles of p-GSK3α/ß (Ser21/9) and p-GSK3α/ß (Tyr279/216) were analyzed by immunohistochemistry and western blotting. Four different permanent HNSCC cell lines were exposed to the potent GSK3α/ß inhibitor SB 216763. Cell viability was controlled via the MTT test. Cell migration was quantified with the Real Time Cell Analyzer (RCTA) xCELLigence. Regulation of the epithelial-mesenchymal transition (EMT) was measured with the Human Epithelial to Mesenchymal Transition (EMT) RT2 Profiler™ PCR Array and scratch assays. Taqman probes were used to detect the specific gene expression profiles of inflammatory cytokines Interleukin IL1ß, IL6, IL8, IL10, TNFα and IFNß. RESULTS: Exposure of permanent HNSCC cell lines to the specific GSK3α/ß inhibitor SB 216763 leads to significant growth inhibition, inhibition of migration and decreased levels of active GSK3α/ß in a dose dependent manner.Exposure of HNSCC lines to SB 216763 also resulted in a markable shift of EMT markers and functional EMT dysregulation. Functionally GSK3 differentially mediates the expression of TLR4- and TLR3-induced inflammatory cytokines in HNSCC, whereas no effect of SB 216763 on the NFkB activity was noticed. CONCLUSION: GSK3α/ß plays a crucial role in a variety of regulatory networks for HNSCC cancer progression as it drives proliferation or migration and thus GSK3 could serve as an interesting target for clinical drug development.
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Patients with primary biliary cholangitis (PBC) can show biochemical, serological and/or histological features of autoimmune hepatitis (AIH). The term 'AIH-PBC overlap syndrome' has been used frequently for these cases and implies the coexistence of two separate diseases. However, the boundaries between 'classical' PBC, PBC with features of AIH and 'classical' AIH are difficult to define, and therefore the term 'variant syndrome' should be preferred. A variant syndrome must primarily be assumed in PBC patients showing pronounced hepatitic activity, either expressed by elevated transaminases and raised levels of serum IgG/gammaglobulins or more specifically by liver biopsy showing a modified hepatitis activity index (mHAI) score of >4/18. The presence of AIH-specific autoantibodies also supports the diagnosis of a variant syndrome. The diagnosis must not be missed because individually adapted immunosuppressive treatment, analogous to AIH therapy, appears to have an important beneficial impact on the prognosis and should therefore be offered to these patients.
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Hepatitis Autoinmune/diagnóstico , Cirrosis Hepática Biliar/diagnóstico , Enfermedades Indiferenciadas del Tejido Conectivo/diagnóstico , Adulto , Autoanticuerpos/sangre , Biopsia , Femenino , Hepatitis Autoinmune/tratamiento farmacológico , Hepatitis Autoinmune/inmunología , Humanos , Inmunosupresores/uso terapéutico , Cirrosis Hepática Biliar/tratamiento farmacológico , Cirrosis Hepática Biliar/inmunología , Masculino , Pronóstico , Enfermedades Indiferenciadas del Tejido Conectivo/inmunologíaRESUMEN
The strictly anaerobic, Gram-positive bacterium Clostridium luticellarii, which has straight or slightly curved rod-shaped cells, polar endospores, and peritrichous flagella, is used for the production of strong aromatic Chinese liquors. C. luticellarii is able to produce butanoic acid. The draft genome sequence consists of 3.757 Mbp, including 3,632 predicted protein-encoding genes.
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Action control deficits of schizophrenia patients result from frontostriatal brain abnormalities and presumably reflect an impairment of selective cognitive processes. This study aimed at dissociating two different levels of action control in saccades toward and away from visual stimuli (pro- and antisaccades). Results of previous studies suggested that task switch effects (between pro- and antisaccades) reflect the persistence of a task-specific production rule and refer to the level of task selection, whereas response switch effects (between leftward and rightward saccades) point to the persistence of a specific response program, referring to the level of response selection. In the present study, task switching and response switching were investigated in 20 schizophrenia patients and 20 control subjects. Groups did not differ concerning task switch effects. In contrast, response switching entailed a stronger enhancement of error rates in patients, suggesting a specific deficit on the level of response selection in schizophrenia. The deficit was associated with spatial working memory capacities, confirming and specifying existing hypotheses on a relationship between working memory and action control.