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1.
Transpl Int ; 37: 12310, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38317690

RESUMO

Since the early days of clinical lung transplantation the preservation of donor organs has become a fairly standardized procedure and most centers do follow similar processes. This includes the use of low-potassium high dextran flush solutions and static cold storage (SCS) in a cooler filled with ice. Depending on the length of SCS, organs usually arrive at the recipient hospital at a temperature of 0°C-4°C. The question of the optimal storage temperature for donor lung preservation has been revisited as data from large animal experiments demonstrated that organs stored at 10°C experience less mitochondrial damage. Thus, prolonged cold ischemic times can be better tolerated at 10°C-even in pre-damaged organs. The clinical applicability of these findings was demonstrated in an international multi-center observational study including three high-volume lung transplant centers. Total clinical preservation times of up to 24 hrs have been successfully achieved in organs stored at 10°C without hampering primary organ function and short-term outcomes. Currently, a randomized-controlled trial (RCT) is recruiting patients with the aim to compare standard SCS on ice with prolonged SCS protocol at 10°C. If, as anticipated, this RCT confirms data from previous studies, lung transplantation could indeed become a semi-elective procedure.


Assuntos
Transplante de Pulmão , Preservação de Órgãos , Animais , Humanos , Temperatura Baixa , Gelo , Pulmão , Transplante de Pulmão/métodos , Estudos Observacionais como Assunto , Preservação de Órgãos/métodos , Perfusão/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto , Temperatura , Estudos Multicêntricos como Assunto
2.
Rev Sci Instrum ; 94(10)2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37815423

RESUMO

At the ReAccelerator within the Facility for Rare Isotope Beams, a combination of an interchangeable aluminum foil and a silicon detector was developed to quantify isobaric contamination in rare isotope beams. The device is simple to operate and is now used routinely. In this article, we describe the system and show an application of the device to determine the level of contamination of an Si-32 rare isotope beam by stable S-32. In addition, we describe how the new diagnostic device helped confirm an enhancement of the beam purity prior to beam delivery to experiments.

3.
AJNR Am J Neuroradiol ; 44(6): 707-715, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37230540

RESUMO

BACKGROUND AND PURPOSE: Vein of Galen malformation is a rare congenital cerebrovascular malformation. In affected patients, increased cerebral venous pressure constitutes an important etiologic factor for the development of brain parenchymal damage. The aim of this study was to investigate the potential of serial cerebral venous Doppler measurements to detect and monitor increased cerebral venous pressure. MATERIALS AND METHODS: This was a retrospective monocentric analysis of ultrasound examinations within the first 9 months of life in patients with vein of Galen malformation admitted at <28 days of life. Categorization of perfusion waveforms in the superficial cerebral sinus and veins into 6 patterns was based on antero- and retrograde flow components. We performed an analysis of flow profiles across time and correlation with disease severity, clinical interventions, and congestion damage on cerebral MR imaging. RESULTS: The study included 44 Doppler ultrasound examinations of the superior sagittal sinus and 36 examinations of the cortical veins from 7 patients. Doppler flow profiles before interventional therapy correlated with disease severity determined by the Bicêtre Neonatal Evaluation Score (Spearman ρ = -0.97, P = < .001). At this time, 4 of 7 patients (57.1%) showed a retrograde flow component in the superior sagittal sinus, whereas after embolization, none of the 6 treated patients presented with a retrograde flow component. Only patients with a high retrograde flow component (equal or more than one-third retrograde flow, n = 2) showed severe venous congestion damage on cerebral MR imaging. CONCLUSIONS: Flow profiles in the superficial cerebral sinus and veins appear to be a useful tool to noninvasively detect and monitor cerebral venous congestion in vein of Galen malformation.


Assuntos
Veias Cerebrais , Hiperemia , Malformações da Veia de Galeno , Recém-Nascido , Humanos , Seio Sagital Superior/diagnóstico por imagem , Malformações da Veia de Galeno/complicações , Malformações da Veia de Galeno/diagnóstico por imagem , Estudos Retrospectivos , Veias Cerebrais/diagnóstico por imagem , Veias Cerebrais/anormalidades , Ultrassonografia Doppler
4.
Zoonoses Public Health ; 69(6): 673-681, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35546073

RESUMO

While previous research on zoonotic transmission of community-acquired Clostridioides difficile infection (CA-CDI) focused on food-producing animals, the present study aimed to investigate whether dogs are carriers of resistant and/or virulent C. difficile strains. Rectal swabs were collected from 323 dogs and 38 C. difficile isolates (11.8%) were obtained. Isolates were characterized by antimicrobial susceptibility testing, whole-genome sequencing (WGS) and a DNA hybridization assay. Multilocus sequence typing (MLST), core genome MLST (cgMLST) and screening for virulence and antimicrobial resistance genes were performed based on WGS. Minimum inhibitory concentrations for erythromycin, clindamycin, tetracycline, vancomycin and metronidazole were determined by E-test. Out of 38 C. difficile isolates, 28 (73.7%) carried genes for toxins. The majority of isolates belonged to MLST sequence types (STs) of clade I and one to clade V. Several isolates belonged to STs previously associated with human CA-CDI. However, cgMLST showed low genetic relatedness between the isolates of this study and C. difficile strains isolated from humans in Austria for which genome sequences were publicly available. Four isolates (10.5%) displayed resistance to three of the tested antimicrobial agents. Isolates exhibited resistance to erythromycin, clindamycin, tetracycline and metronidazole. These phenotypic resistances were supported by the presence of the resistance genes erm(B), cfr(C) and tet(M). All isolates were susceptible to vancomycin. Our results indicate that dogs may carry virulent and antimicrobial-resistant C. difficile strains.


Assuntos
Anti-Infecciosos , Clostridioides difficile , Infecções por Clostridium , Doenças do Cão , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Anti-Infecciosos/farmacologia , Clindamicina/farmacologia , Clostridioides , Clostridioides difficile/genética , Infecções por Clostridium/epidemiologia , Infecções por Clostridium/veterinária , Doenças do Cão/tratamento farmacológico , Doenças do Cão/epidemiologia , Cães , Farmacorresistência Bacteriana/genética , Eritromicina , Genótipo , Humanos , Metronidazol/farmacologia , Testes de Sensibilidade Microbiana/veterinária , Tipagem de Sequências Multilocus/veterinária , Tetraciclinas , Vancomicina/farmacologia
5.
Sci Rep ; 12(1): 7072, 2022 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-35490174

RESUMO

Alemtuzumab is a monoclonal antibody targeting CD52, used as induction therapy after lung transplantation (LTx). Its engagement produces a long-lasting immunodepletion; however, the mechanisms driving cell reconstitution are poorly defined. We hypothesized that miRNAs are involved in this process. The expression of a set of miRNAs, cytokines and co-signaling molecules was measured with RT-qPCR and flow cytometry in prospectively collected serum samples of LTx recipients, after alemtuzumab or no induction therapy. Twenty-six LTx recipients who received alemtuzumab and twenty-seven matched LTx recipients without induction therapy were included in the analysis. One year after transplantation four miRNAs were differentially regulated: miR-23b (p = 0.05) miR-146 (p = 0.04), miR-155 (p < 0.001) and miR-486 (p < 0.001). Expression of 3 miRNAs changed within the alemtuzumab group: miR-146 (p < 0.001), miR-155 (p < 0.001) and miR-31 (p < 0.001). Levels of IL-13, IL-4, IFN-γ, BAFF, IL-5, IL-9, IL-17F, IL-17A and IL-22 were different one year after transplantation compared to baseline. In no-induction group, concentration of sCD27, sB7.2 and sPD-L1 increased overtime. Expression of miR-23b, miR-146, miR-486, miR-155 and miR-31 was different in LTx recipients who received alemtuzumab compared to recipients without induction therapy. The observed cytokine pattern suggested proliferation of specific B cell subsets in alemtuzumab group and co-stimulation of T-cells in no-induction group.


Assuntos
MicroRNA Circulante , Transplante de Pulmão , MicroRNAs , Alemtuzumab/uso terapêutico , Citocinas/metabolismo , Quimioterapia de Indução , MicroRNAs/genética
6.
Hautarzt ; 73(1): 27-39, 2022 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-34821976

RESUMO

BACKGROUND: Psoriasis (Pso) and atopic dermatitis (AD) are chronic skin diseases that result in significant physical and psychological impairment, financial burden, and loss of quality of life. According to previous data, there are regional differences in healthcare. OBJECTIVES: The aim was to analyse the epidemiology as well as the treatment of insured people with Pso and AD in Germany in a regional comparison. METHODS: Data of the insurance company Techniker Krankenkasse for the year 2019 regarding treatment prevalences as well as drug prescriptions on the regional level for all physicians were examined. RESULTS: In 2019 the overall prevalence of Pso was 2.5% (about 2 million insured people in Germany) and AD was 4.2% (about 3.6 million insured people). In Pso, new guideline-compliant drugs were frequently utilised, yet systemic glucocorticosteroids (GCS) were still disproportionally prescribed. Regionally, there were pronounced disparities with higher prescription rates of the new drugs in the north and east. Insured people with AD most frequently received topical GCS (approx. 88%), of which most were class III (66%), and significantly less frequently calcineurin inhibitors (< 10%), which also conform to guidelines. Systemically, GCS were by far most commonly used (about 25% of all insured people with drug prescriptions). Dupilumab, the only long-term drug approved in 2019, was very rarely prescribed, accounting for less than 1%. Again, large regional differences similar to Pso were found. CONCLUSION: Pso and AD show relevant disparities and gaps in drug care in the regional comparison despite uniform national guidelines and patient needs. The barriers to appropriate modern pharmaceuticals need to be clarified and mitigated.


Assuntos
Dermatite Atópica , Eczema , Psoríase , Atenção à Saúde , Dermatite Atópica/diagnóstico , Dermatite Atópica/tratamento farmacológico , Dermatite Atópica/epidemiologia , Alemanha/epidemiologia , Humanos , Psoríase/diagnóstico , Psoríase/tratamento farmacológico , Psoríase/epidemiologia , Qualidade de Vida
7.
Pneumologie ; 75(10): 753-760, 2021 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-34428830

RESUMO

Health status and quality of life are impaired in patients with idiopathic pulmonary fibrosis (IPF) and idiopathic non-specific interstitial fibrosis (iNSIP). In Germany exists only the K-BILD questionnaire for patients with ILD 1 in a professional translation by Kreuter et al. 2 This questionnaire focuses on the main problems in patients with progressive lung fibrosis in a limited manner. Therefore a new quality of life questionnaire for patients with idiopathic pulmonary fibrosis was developed and linguistically validated. METHODS: The linguistic validation of our questionnaire was carried out in a multistage process in collaboration with the developer of the questionnaire and bilingual, professional translators. Review by the developers and back translations as well as clinical assessment by IPF- and iNSIP-patients ensured that the translated questionnaire reflected the intention of the original English version of our questionnaire.Cross-validation was carried out with the St. Georges Respiratory Questionnaire (SGRQ). RESULTS: The new questionnaire concerning the health status was composed in English and German language. The questions cover five scales (sensitivity, selectivity and symptoms like breathlessness and cough and a visual analog scale on general health status) with 23 items. CONCLUSIONS: The results show that the FFB maps the special needs of the patients with IPF and iNSIP well and can support clinical and scientific questions and can be helpful in monitoring the clinical course.


Assuntos
Fibrose Pulmonar Idiopática , Qualidade de Vida , Humanos , Fibrose Pulmonar Idiopática/diagnóstico , Idioma , Linguística , Inquéritos e Questionários
8.
Vet Microbiol ; 254: 109005, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33582485

RESUMO

Information about livestock carrying methicillin-resistant coagulase-negative staphylococci and mammaliicocci (MRCoNS/MRM) is scarce. The study was designed to gain knowledge of the prevalence, the phenotypic and genotypic antimicrobial resistance and the genetic diversity of MRCoNS/MRM originating from ruminants and New World camelids. In addition, a multi-locus sequence typing scheme for the characterization of Mammaliicoccus (formerly Staphylococcus) sciuri was developed. The study was conducted from April 2014 to January 2017 at the University Clinic for Ruminants and the Institute of Microbiology at the University of Veterinary Medicine Vienna. Seven hundred twenty-three nasal swabs originating from ruminants and New World camelids with and without clinical signs were examined. After isolation, MRCoNS/MRM were identified by MALDI-TOF, rpoB sequencing and typed by DNA microarray-based analysis and PCR. Antimicrobial susceptibility testing was conducted by agar disk diffusion. From all 723 nasal swabs, 189 MRCoNS/MRM were obtained. Members of the Mammaliicoccus (M.) sciuri group were predominant (M. sciuri (n = 130), followed by M. lentus (n = 43), M. fleurettii (n = 11)). In total, 158 out of 189 isolates showed phenotypically a multi-resistance profile. A seven-loci multi-locus sequence typing scheme for M. sciuri was developed. The scheme includes the analysis of internal segments of the house-keeping genes ack, aroE, ftsZ, glpK, gmk, pta1 and tpiA. In total, 28 different sequence types (STs) were identified among 92 selected M. sciuri isolates. ST1 was the most prevalent ST (n = 35), followed by ST 2 (n = 15), ST3 and ST5 (each n = 5), ST4 (n = 3), ST6, ST7, ST8, ST9, ST10 and ST11 (each n = 2).


Assuntos
Camelídeos Americanos/microbiologia , Variação Genética , Resistência a Meticilina , Ruminantes/microbiologia , Infecções Estafilocócicas/veterinária , Staphylococcus/classificação , Staphylococcus/genética , Animais , Antibacterianos/farmacologia , Técnicas de Tipagem Bacteriana/métodos , DNA Bacteriano/genética , Farmacorresistência Bacteriana Múltipla/genética , Genes Bacterianos/genética , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus/métodos , Infecções Estafilocócicas/epidemiologia , Staphylococcus/efeitos dos fármacos
10.
Pneumologie ; 75(5): 337-343, 2021 May.
Artigo em Alemão | MEDLINE | ID: mdl-33147638

RESUMO

INTRODUCTION: Besides dyspnea a dry cough is one of the main symptoms in patients with pulmonary fibrosis. Little is known about the 24-hour-variability of this symptom. Moreover, it is unclear if other auscultation phenomena occur. METHODS: A long-term auscultation for 24-hours was performed in patients with fibrotic lung diseases (LEOSound, Löwenstein Medical GmbH & Co. KG, Medical-Electronics, Bad Ems, Germany). Coughing and wheezing sounds were recorded. For the following analysis the 24-hour period was divided into two intervals of 12 hours each (daytime and nighttime). Events were registered in epochs (at least one event in 30 seconds). RESULTS: 20 patients were included (6 with nonspecific interstitial pneumonia and 14 with idiopathic pulmonary fibrosis). On average 166 coughing epochs were recorded in a 24-hour-period (day/night 116/50; P < 0.001). Moreover, 203 wheezing epochs were registered (day/night 84/119; P = 0.273). Auscultation phenomena did not correlate with spirometric and bodyplethymographic data, nor with data of diffusion capacity. DISCUSSION: The study is showing the clinical potential of long-term auscultation in patients with fibrotic lung diseases. Especially the findings concerning the coughing symptoms were remarkable. It could be shown that there was a decrease of coughing during nighttime in comparison to daytime. In contrast to this, wheezing sounds were increasing at nighttime. The clinical relevance of this finding is yet to be assessed. Finally, there was no correlation between the severity of the disease measured by functional diagnostics and the amount of coughing.


Assuntos
Tosse , Doenças Pulmonares Intersticiais , Auscultação , Tosse/diagnóstico , Alemanha , Humanos , Pulmão , Doenças Pulmonares Intersticiais/diagnóstico , Sons Respiratórios
11.
J Comp Pathol ; 178: 56-60, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32800110

RESUMO

We report the first isolation of Acinetobacter kookii from a Rothschild's giraffe calf (Giraffa camelopardalis rothschildi) that had severe polyarthritis. The isolate was resistant to more than one representative of each of four classes of antibiotics (penicillins, macrolides, lincosamides and tetracyclines). As A. kookii has not been previously associated with disease in humans or animals, it may be an emerging opportunistic pathogen posing a threat to immunocompromised patients. Furthermore, as transmission of Acinetobacter spp. with similar patterns of antimicrobial resistance has been previously reported in human and animal populations, special care should be taken when handling infected animals.


Assuntos
Acinetobacter , Artrite/veterinária , Girafas , Acinetobacter/efeitos dos fármacos , Acinetobacter/isolamento & purificação , Infecções por Acinetobacter/tratamento farmacológico , Infecções por Acinetobacter/patologia , Infecções por Acinetobacter/veterinária , Animais , Animais de Zoológico/microbiologia , Antibacterianos/uso terapêutico , Artrite/microbiologia , Doenças Transmissíveis Emergentes/veterinária , Resistência a Medicamentos , Girafas/microbiologia , Masculino
12.
Sci Rep ; 10(1): 5380, 2020 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-32214122

RESUMO

Dogs share many chronic morbidities with humans and thus represent a powerful model for translational research. In comparison to rodents, the canine ganglioside metabolism more closely resembles the human one. Gangliosides are components of the cell plasma membrane playing a role in neuronal development, intercellular communication and cellular differentiation. The present in vitro study aimed to characterize structural and functional changes induced by GM1 ganglioside (GM1) in canine dorsal root ganglia (DRG) neurons and interactions of GM1 with nerve growth factor (NGF) and fibroblast growth factor (FGF2) using immunofluorescence for several cellular proteins including neurofilaments, synaptophysin, and cleaved caspase 3, transmission electron microscopy, and electrophysiology. GM1 supplementation resulted in increased neurite outgrowth and neuronal survival. This was also observed in DRG neurons challenged with hypoxia mimicking neurodegenerative conditions due to disruptions of energy homeostasis. Immunofluorescence indicated an impact of GM1 on neurofilament phosphorylation, axonal transport, and synaptogenesis. An increased number of multivesicular bodies in GM1 treated neurons suggested metabolic changes. Electrophysiological changes induced by GM1 indicated an increased neuronal excitability. Summarized, GM1 has neurotrophic and neuroprotective effects on canine DRG neurons and induces functional changes. However, further studies are needed to clarify the therapeutic value of gangliosides in neurodegenerative diseases.


Assuntos
Fator 2 de Crescimento de Fibroblastos/metabolismo , Gangliosídeo G(M1)/metabolismo , Fator de Crescimento Neural/metabolismo , Fatores de Crescimento Neural/metabolismo , Animais , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Cães , Gânglios Espinais/citologia , Gânglios Espinais/metabolismo , Gânglios Espinais/fisiologia , Gangliosídeos/metabolismo , Neurônios/metabolismo , Fármacos Neuroprotetores/farmacologia
13.
Med Klin Intensivmed Notfmed ; 115(4): 300-306, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31392353

RESUMO

BACKGROUND: The spontaneous breathing trial (SBT) is a well-established diagnostic test for predicting extubation failure in intubated intensive care unit (ICU) patients. However, the SBT has not been evaluated in a specific cohort of tracheostomized patients in whom weaning is prolonged and ultimately unsuccessful. OBJECTIVE: The aim of the trial was to investigate the relevance of SBT failure criteria in chronic respiratory failure subjects undergoing long-term invasive home mechanical ventilation following tracheostomy and weaning failure. METHODS: Measurement of all established failure criteria including pneumotachygraphical assessment of the rapid shallow breathing index (RSBI) took place during an SBT. The decision to continue spontaneous breathing was based on failure criteria as well as the subjective willingness of the patient. RESULTS: Fifteen subjects with a median age of 58 years (interquartile range [IQR] 44-74) were studied; 10 with COPD, 4 with neuromuscular diseases and 1 with both. Twelve subjects met the SBT failure criteria within 30 min, but one third of these subjects were still able to continue with spontaneous breathing. In contrast, 3 subjects could not be weaned despite the SBT being successful. An increased RSBI was the most frequently observed SBT failure criterion (57% of all SBT). However, the SBT varied substantially in individual subjects who were able to sustain spontaneous breathing, despite having reached the cut-off for SBT failure. CONCLUSION: The SBT was of low predictive value regarding spontaneous breathing ability in chronic respiratory failure subjects with prolonged, unsuccessful weaning.


Assuntos
Respiração Artificial , Desmame do Respirador , Extubação , Estudos de Coortes , Humanos , Pessoa de Meia-Idade , Traqueostomia
14.
Phys Rev Lett ; 123(23): 239905, 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31868474

RESUMO

This corrects the article DOI: 10.1103/PhysRevLett.120.032701.

16.
J Mater Sci Mater Med ; 30(11): 121, 2019 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-31655914

RESUMO

Composite scaffolds can improve regenerative capacities of scaffolds in various tissue-engineering approaches. In order to generate a 3D printable scaffold that is capable of cartilage regeneration, decellularized extracellular matrix (DECM) of porcine nasal cartilage was added to 3D printed polycaprolactone (PCL) scaffolds. Subsequently, scaffolds (PCL, PCL/DECM and DECM) were seeded with human primary nasoseptal chondrocytes and differentiated with cartilage inductive medium for up to 42 days in vitro. Afterwards samples were analyzed with scanning electron microscopy, histology, biochemical assays and gene expression analysis. In short, results showed cell attachment and proliferation on all scaffolds. There was a trend towards ossification on pure PCL scaffolds, whereas we found evidence for cartilage tissue formation on DECM scaffolds as well as on PCL/DECM scaffolds. Moreover, biochemical analysis indicated an enhanced differentiation on novel PCL/DECM scaffolds. In conclusion, the addition of DECM to 3D printable PCL scaffolds may yield a new composite material for regenerative approaches in cartilage for facial reconstructive surgery. Further research will be necessary to evaluate these findings in vivo.


Assuntos
Matriz Extracelular , Cartilagens Nasais/fisiologia , Tecidos Suporte , Animais , Condrócitos , Condrogênese , Humanos , Impressão Tridimensional , Regeneração , Suínos , Engenharia Tecidual/métodos
18.
Appl Environ Microbiol ; 85(9)2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30824455

RESUMO

Multidrug-resistant bacterial pathogens are becoming increasingly prevalent, and novel strategies to treat bacterial infections caused by these organisms are desperately needed. Bacterial central metabolism is crucial for catabolic processes and provides precursors for anabolic pathways, such as the biosynthesis of essential biomolecules like amino acids or vitamins. However, most essential pathways are not regarded as good targets for antibiotic therapy since their products might be acquired from the environment. This issue raises doubts about the essentiality of such targets during infection. A putative target in bacterial anabolism is the methionine biosynthesis pathway. In contrast to humans, almost all bacteria carry methionine biosynthesis pathways which have often been suggested as putative targets for novel anti-infectives. While the growth of methionine auxotrophic strains can be stimulated by exogenous methionine, the extracellular concentrations required by most bacterial species are unknown. Furthermore, several phenotypic characteristics of methionine auxotrophs are only partly reversed by exogenous methionine. We investigated methionine auxotrophic mutants of Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli (all differing in methionine biosynthesis enzymes) and found that each needed concentrations of exogenous methionine far exceeding that reported for human serum (∼30 µM). Accordingly, these methionine auxotrophs showed a reduced ability to proliferate in human serum. Additionally, S. aureus and P. aeruginosa methionine auxotrophs were significantly impaired in their ability to form and maintain biofilms. Altogether, our data show intrinsic defects of methionine auxotrophs. This result suggests that the pathway should be considered for further studies validating the therapeutic potential of inhibitors.IMPORTANCE New antibiotics that attack novel targets are needed to circumvent widespread resistance to conventional drugs. Bacterial anabolic pathways, such as the enzymes for biosynthesis of the essential amino acid methionine, have been proposed as potential targets. However, the eligibility of enzymes in these pathways as drug targets is unclear because metabolites might be acquired from the environment to overcome inhibition. We investigated the nutritional needs of methionine auxotrophs of the pathogens Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli We found that each auxotrophic strain retained a growth disadvantage at methionine concentrations mimicking those available in vivo and showed that biofilm biomass was strongly influenced by endogenous methionine biosynthesis. Our experiments suggest that inhibition of the methionine biosynthesis pathway has deleterious effects even in the presence of external methionine. Therefore, additional efforts to validate the effects of methionine biosynthesis inhibitors in vivo are warranted.


Assuntos
Biofilmes/efeitos dos fármacos , Escherichia coli/fisiologia , Metionina/deficiência , Pseudomonas aeruginosa/fisiologia , Staphylococcus aureus/fisiologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Mutação , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/genética , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/genética
19.
Clin Microbiol Infect ; 25(5): 630.e1-630.e6, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30076974

RESUMO

OBJECTIVES: To investigate the faecal carriage of optrA-positive enterococci among asymptomatic healthy humans in Hangzhou, China, and to characterize the genetic context of optrA. METHODS: A total of 3458 stool samples from healthy individuals were collected and cultured on a selective medium containing 10 mg/L florfenicol and resulting enterococci were screened for the presence of optrA by PCR. OptrA variants were determined by amino acid sequence comparison with the original OptrA from Enterococcus faecalis E349. Whole genome sequencing and PCR mapping were performed to obtain and analyse the genetic environment of optrA. RESULTS: Similar optrA carriage rates (∼3.5%) were detected in samples from adults (55/1558) and children (66/1900). Linezolid resistance rates for E. faecalis, Enterococcus faecium and other Enterococcus species were 58.5% (38/65), 42.3% (11/26) and 0% (0/31), respectively. Nineteen OptrA variants exhibiting different linezolid MICs were identified. Isolates carrying wild-type OptrA and variants RDK, KLDP, KD, D, RDKP, and EDP generally demonstrated linezolid MICs ≥8 mg/L. The OptrA variants, with fexA upstream and erm(A) downstream, were flanked by IS1216E at one or both ends. The fexA-optrA(wild-type) was located downstream of a Tn554 transposon, and was inserted into the radC gene. The EDM variant was detected in 31/73 enterococci with linezolid MICs ≤4 mg/L. Despite the variable genetic context, Tn558-araC-optrA(EDM)-erm(A)-met was the most common gene array. CONCLUSIONS: This study revealed a correlation between linezolid MIC, genetic context and OptrA variant. Intestinal colonization of healthy individuals by optrA-positive enterococci is a concern, and active epidemiological surveillance of optrA is warranted.


Assuntos
Proteínas de Bactérias/genética , Portador Sadio/epidemiologia , Farmacorresistência Bacteriana , Enterococcus faecalis/isolamento & purificação , Enterococcus faecium/isolamento & purificação , Fezes/microbiologia , Infecções por Bactérias Gram-Positivas/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/farmacologia , Portador Sadio/microbiologia , Criança , Pré-Escolar , China/epidemiologia , Enterococcus faecalis/genética , Enterococcus faecium/genética , Feminino , Variação Genética , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Lactente , Recém-Nascido , Linezolida/farmacologia , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Sequenciamento Completo do Genoma , Adulto Jovem
20.
Nervenarzt ; 89(10): 1083-1094, 2018 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-30120488

RESUMO

BACKGROUND: The microtubule-associated tau protein is the defining denominator of a group of neurodegenerative diseases termed tauopathies. OBJECTIVE: Provide a timely state of the art review on recent scientific advances in the field of tauopathies. MATERIAL AND METHODS: Systematic review of the literature from the past 10 years. RESULTS: Tau proteins are increasingly being recognized as a highly variable protein, underlying and defining a spectrum of molecularly defined diseases, with a clinical spectrum ranging from dementia to hypokinetic movement disorders. Genetic variation at the tau locus can trigger disease or modify disease risk. Tau protein alterations can damage nerve cells and propagate pathologies through the brain. Thus, tau proteins may serve both as a serological and imaging biomarker. Tau proteins also provide a broad spectrum of rational therapeutic interventions to prevent disease progression. This knowledge has led to modern clinical trials. CONCLUSION: The field of tauopathies is in a state of dynamic and rapid progress, requiring close interdisciplinary collaboration.


Assuntos
Tauopatias , Proteínas tau , Encéfalo/patologia , Variação Genética , Humanos , Tauopatias/genética , Tauopatias/patologia , Tauopatias/terapia , Proteínas tau/genética
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