Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 25
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Artigo em Inglês | MEDLINE | ID: mdl-30782988

RESUMO

Vancomycin-resistant Enterococcus faecium (VREfm) is a frequent cause of nosocomial outbreaks. In the second half of 2015, a sharp increase in the incidence of VREfm was observed at our university medical center. Next-generation sequencing (NGS) was used to analyze the first isolates of VREfm recovered from patients between 2010 and 2016 (n = 773) in order to decipher epidemiological change, outbreak dynamics, and possible transmission routes. VREfm isolates were analyzed using whole-genome sequencing followed by sequence type extraction and phylogenetic analysis. We examined epidemiological data, room occupancy data, and patient transferals and calculated an intensity score for patient-to-patient contact. Phylogenetic analysis revealed the presence of 38 NGS clusters and 110 single clones. The increase of VREfm was caused mainly by the expansion of two newly introduced NGS clusters, comprising VanB-type strains determined by multilocus sequence typing (MLST) as sequence type 80 (ST80) and ST117. By combining phylogenetic information with epidemiological data, intrahospital transmission could be demonstrated, however to a lesser extent than initially expected based solely on epidemiological data. The outbreak clones were continuously imported from other hospitals, suggesting a change in the epidemiological situation at a regional scale. By tracking intrahospital patient transferals, two major axes could be identified that contributed to the spread of VREfm within the hospital. NGS-based outbreak analysis revealed a dramatic change in the local and regional epidemiology of VREfm, emphasizing the role of health care networks in the spread of VREfm.

2.
J Clin Microbiol ; 56(11)2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30135233

RESUMO

Klebsiella pneumoniae and related species are frequent causes of nosocomial infections and outbreaks. Therefore, quick and reliable strain typing is crucial for the detection of transmission routes in the hospital. The aim of this study was to evaluate Fourier transform infrared spectroscopy (FTIR) and matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) as rapid methods for typing clinical Klebsiella isolates in comparison to whole-genome sequencing (WGS), which was considered the gold standard for typing and identification. Here, 68 clinical Klebsiella strains were analyzed by WGS, FTIR, and MALDI-TOF MS. FTIR showed high discriminatory power in comparison to the WGS reference, whereas MALDI-TOF MS exhibited a low ability to type the isolates. MALDI-TOF mass spectra were further analyzed for peaks that showed high specificity for different Klebsiella species. Phylogenetic analysis revealed that the Klebsiella isolates comprised three different species: K. pneumoniae, K. variicola, and K. quasipneumoniae Genome analysis showed that MALDI-TOF MS can be used to distinguish K. pneumoniae from K. variicola due to shifts of certain mass peaks. The peaks were tentatively identified as three ribosomal proteins (S15p, L28p, L31p) and one stress response protein (YjbJ), which exhibit amino acid differences between the two species. Overall, FTIR has high discriminatory power to recognize the clonal relationship of isolates, thus representing a valuable tool for rapid outbreak analysis and for the detection of transmission events due to fast turnaround times and low costs per sample. Furthermore, specific amino acid substitutions allow the discrimination of K. pneumoniae and K. variicola by MALDI-TOF MS.

3.
Front Immunol ; 9: 79, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29459858

RESUMO

We previously showed that in mice infected with Leishmania major type I interferons (IFNs) initiate the innate immune response to the parasite at day 1 and 2 of infection. Here, we investigated which type I IFN subtypes are expressed during the first 8 weeks of L. major infection and whether type I IFNs are essential for a protective immune response and clinical cure of the disease. In self-healing C57BL/6 mice infected with a high dose of L. major, IFN-α4, IFN-α5, IFN-α11, IFN-α13, and IFN-ß mRNA were most prominently regulated during the course of infection. In C57BL/6 mice deficient for IFN-ß or the IFN-α/ß-receptor chain 1 (IFNAR1), development of skin lesions and parasite loads in skin, draining lymph node, and spleen was indistinguishable from wild-type (WT) mice. In line with the clinical findings, C57BL/6 IFN-ß-/-, IFNAR1-/-, and WT mice exhibited similar mRNA expression levels of IFN-γ, interleukin (IL)-4, IL-12, IL-13, inducible nitric oxide synthase, and arginase 1 during the acute and late phase of the infection. Also, myeloid dendritic cells from WT and IFNAR1-/- mice produced comparable amounts of IL-12p40/p70 protein upon exposure to L. major in vitro. In non-healing BALB/c WT mice, the mRNAs of IFN-α subtypes (α2, α4, α5, α6, and α9) were rapidly induced after high-dose L. major infection. However, genetic deletion of IFNAR1 or IFN-ß did not alter the progressive course of infection seen in WT BALB/c mice. Finally, we tested whether type I IFNs and/or IL-12 are required for the prophylactic effect of CpG-oligodesoxynucleotides (ODN) in BALB/c mice. Local and systemic administration of CpG-ODN 1668 protected WT and IFN-ß-/- mice equally well from progressive leishmaniasis. By contrast, the protective effect of CpG-ODN 1668 was lost in BALB/c IFNAR1-/- (despite a sustained suppression of IL-4) and in BALB/c IL-12p35-/- mice. From these data, we conclude that IFN-ß and IFNAR1 signaling are dispensable for a curative immune response to L. major in C57BL/6 mice and irrelevant for disease development in BALB/c mice, whereas IL-12 and IFN-α subtypes are essential for the disease prevention by CpG-ODNs in this mouse strain.

4.
Eye (Lond) ; 32(6): 1021-1027, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29379104

RESUMO

PURPOSE: The aim of the study was to evaluate the bacterial contamination level of contact surfaces on slit lamps and the grip areas of lenses. METHODS: Within unannounced audits, two regions of the slit lamps (headrest and joystick), indirect ophthalmoscopy devices, and ultrasound probes were obtained with rayon-tipped swab. Non-contact lenses used for indirect fundoscopy were pressed on RODAC (Replicate Organism Detection and Counting) plates. One hundred and eighty-one surfaces were sampled. The total number of colony-forming units was assessed and bacterial species were identified. Spa-typing and antimicrobial susceptibility testing were performed from Staphylococcus aureus isolates. RESULTS: Among the total bacterial isolates from ophthalmological equipment (lenses: 51 of 78, slit lamps: 43 of 88, ophthalmoscopy helmets: 3 of 8, ultrasound probes: 2 of 7), coagulase-negative staphylococci (CNS) was most frequently found, followed by Micrococcus spp. (lenses vs. slit lamps: P < 0.001 and P = 0.01, respectively). The bacterial contamination of lenses (76%) was significantly higher than that of slit lamps (54%) (P < 0.003). A significantly higher contamination with CNS was observed on lenses from residents vs. from consultants (78% vs. 35%, P = 0.01). A total of seven different spa-types of S. aureus were isolated. No correlation was found between S. aureus contamination of different ophthalmological equipments (Spearman's rank correlation coefficient, ρ = 0.04, P = 0.75). Methicillin-resistant S. aureus was not detected. CONCLUSION: Bacterial species of the normal skin flora were isolated from the ophthalmological equipment. The bacterial contamination of the portable devices was significantly higher than that of slit lamps. Therefore, proper hygiene of the mobile instruments should be monitored in order to prevent transmission of bacteria in residents and consultants.

5.
FASEB J ; 32(1): 26-36, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28855276

RESUMO

Leukocytes express formyl-peptide receptors (FPRs), which sense microbe-associated molecular pattern (MAMP) molecules, leading to leukocyte chemotaxis and activation. We recently demonstrated that phenol-soluble modulin (PSM) peptides from highly pathogenic Staphylococcus aureus are efficient ligands for the human FPR2. How PSM detection by FPR2 impacts on the course of S. aureus infections has remained unknown. We characterized the specificity of mouse FPR2 (mFpr2) using a receptor-transfected cell line, homeobox b8 (Hoxb8), and primary neutrophils isolated from wild-type (WT) or mFpr2-/- mice. The influx of leukocytes into the peritoneum of WT and mFpr2-/- mice was analyzed. We demonstrate that mFpr2 is specifically activated by PSMs in mice, and they represent the first secreted pathogen-derived ligands for the mFpr2. Intraperitoneal infection with S. aureus led to lower numbers of immigrated leukocytes in mFpr2-/- compared with WT mice at 3 h after infection, and this difference was not observed when mice were infected with an S. aureus PSM mutant. Our data support the hypothesis that the mFpr2 is the functional homolog of the human FPR2 and that a mouse infection model represents a suitable model for analyzing the role of PSMs during infection. PSM recognition by mFpr2 shapes leukocyte influx in local infections, the typical infections caused by S. aureus-Weiss, E., Hanzelmann, D., Fehlhaber, B., Klos, A., von Loewenich, F. D., Liese, J., Peschel, A., Kretschmer, D. Formyl-peptide receptor 2 governs leukocyte influx in local Staphylococcus aureus infections.


Assuntos
Leucócitos/imunologia , Receptores de Formil Peptídeo/imunologia , Receptores de Lipoxinas/imunologia , Infecções Estafilocócicas/imunologia , Animais , Toxinas Bacterianas/genética , Toxinas Bacterianas/imunologia , Sinalização do Cálcio/imunologia , Degranulação Celular/imunologia , Linhagem Celular , Movimento Celular/imunologia , Modelos Animais de Doenças , Feminino , Genes Bacterianos , Proteínas de Homeodomínio/imunologia , Humanos , Ligantes , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mutação , Neutrófilos/imunologia , Receptores de Formil Peptídeo/deficiência , Receptores de Formil Peptídeo/genética , Staphylococcus aureus/genética , Staphylococcus aureus/imunologia
6.
BMC Genomics ; 18(1): 859, 2017 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-29126393

RESUMO

BACKGROUND: Pseudomonas putida is a Gram-negative, non-fermenting bacterium frequently encountered in various environmental niches. P. putida rarely causes disease in humans, though serious infections and outbreaks have been reported from time to time. Some have suggested that P. putida functions as an exchange platform for antibiotic resistance genes (ARG), and thus represents a serious concern in the spread of ARGs to more pathogenic organisms within a hospital. Though poorly understood, the frequency of ARG exchange between P. putida and the more virulent Pseudomonas aeruginosa and its clinical relevance are particularly important for designing efficient infection control strategies, such as deciding whether high-risk patients colonized with a multidrug resistant but typically low pathogenic P. putida strain should be contact isolated or not. RESULTS: In this study, 21,373 screening samples (stool, rectal and throat swab) were examined to determine the presence of P. putida in a high-risk group of haemato-oncology patients during a 28-month period. A total of 89 P. putida group strains were isolated from 85 patients, with 41 of 89 (46.1%) strains harbouring the metallo-beta-lactamase gene bla VIM. These 41 clinical isolates, plus 18 bla VIM positive environmental P. putida isolates, and 17 bla VIM positive P. aeruginosa isolates, were characterized by whole genome sequencing (WGS). We constructed a maximum-likelihood tree to separate the 59 bla VIM positive P. putida group strains into eight distinct phylogenetic clusters. Bla VIM-1 was present in 6 clusters while bla VIM-2 was detected in 4 clusters. Five P. putida group strains contained both, bla VIM-1 and bla VIM-2 genes. In contrast, all P. aeruginosa strains belonged to a single genetic cluster and contained the same ARGs. Apart from bla VIM-2 and sul genes, no other ARGs were shared between P. aeruginosa and P. putida. Furthermore, the bla VIM-2 gene in P. aeruginosa was predicted to be only chromosomally located. CONCLUSION: These data provide evidence that no exchange of comprehensive ARG harbouring mobile genetic elements had occurred between P. aeruginosa and P. putida group strains during the study period, thus eliminating the need to implement enhanced infection control measures for high-risk patients colonized with a bla VIM positiv P. putida group strains in our clinical setting.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Meio Ambiente , Transferência Genética Horizontal , Genômica , Pseudomonas aeruginosa/genética , Pseudomonas putida/genética , Humanos , Filogenia , Pseudomonas putida/efeitos dos fármacos , Pseudomonas putida/fisiologia
7.
Stem Cells Int ; 2017: 3548435, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28951742

RESUMO

INTRODUCTION: The aim of the study was an evaluation of different approaches for guided bone regeneration (GBR) of peri-implant defects in an in vivo animal model. MATERIALS AND METHODS: In minipigs (n = 15), peri-implant defects around calcium phosphate- (CaP-; n = 46) coated implants were created and randomly filled with (1) blank, (2) collagen/hydroxylapatite/ß-tricalcium phosphate scaffold (CHT), (3) CHT + growth factor cocktail (GFC), (4) jellyfish collagen matrix, (5) jellyfish collagen matrix + GFC, (6) collagen powder, and (7) collagen powder + periodontal ligament stem cells (PDLSC). Additional collagen membranes were used for coverage of the defects. After 120 days of healing, bone growth was evaluated histologically (bone to implant contact (BIC;%)), vertical bone apposition (VBA; mm), and new bone height (NBH; %). RESULTS: In all groups, new bone formation was seen. Though, when compared to the blank group, no significant differences were detected for all parameters. BIC and NBH in the group with collagen matrix as well as the group with the collagen matrix + GFC were significantly less when compared to the collagen powder group (all: p < 0.003). CONCLUSION: GBR procedures, in combination with CaP-coated implants, will lead to an enhancement of peri-implant bone growth. There was no additional significant enhancement of osseous regeneration when using GFC or PDLSC.

8.
J Oral Pathol Med ; 46(10): 911-920, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28677249

RESUMO

BACKGROUND: Uncertainties in detection of oral epithelial dysplasia (OED) frequently result from sampling error especially in inflammatory oral lesions. Endomicroscopy allows non-invasive, "en face" imaging of upper oral epithelium, but parameters of OED are unknown. METHODS: Mucosal nuclei were imaged in 34 toluidine blue-stained oral lesions with a commercial endomicroscopy. Histopathological diagnosis showed four biopsies in "dys-/neoplastic," 23 in "inflammatory," and seven in "others" disease groups. Strength of different assessment strategies of nuclear scoring, nuclear count, and automated nuclear analysis were measured by area under ROC curve (AUC) to identify histopathological "dys-/neoplastic" group. Nuclear objects from automated image analysis were visually corrected. RESULTS: Best-performing parameters of nuclear-to-image ratios were the count of large nuclei (AUC=0.986) and 6-nearest neighborhood relation (AUC=0.896), and best parameters of nuclear polymorphism were the count of atypical nuclei (AUC=0.996) and compactness of nuclei (AUC=0.922). Excluding low-grade OED, nuclear scoring and count reached 100% sensitivity and 98% specificity for detection of dys-/neoplastic lesions. In automated analysis, combination of parameters enhanced diagnostic strength. Sensitivity of 100% and specificity of 87% were seen for distances of 6-nearest neighbors and aspect ratios even in uncorrected objects. Correction improved measures of nuclear polymorphism only. The hue of background color was stronger than nuclear density (AUC=0.779 vs 0.687) to detect dys-/neoplastic group indicating that macroscopic aspect is biased. CONCLUSIONS: Nuclear-to-image ratios are applicable for automated optical in vivo diagnostics for oral potentially malignant disorders. Nuclear endomicroscopy may promote non-invasive, early detection of dys-/neoplastic lesions by reducing sampling error.


Assuntos
Carcinoma in Situ/patologia , Núcleo Celular/patologia , Neoplasias Bucais/patologia , Boca/patologia , Idoso , Idoso de 80 Anos ou mais , Automação , Endoscopia , Epitélio/patologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Microscopia , Pessoa de Meia-Idade , Projetos Piloto
9.
Front Biosci (Schol Ed) ; 9: 180-193, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-27814584

RESUMO

The regeneration of periodontal tissues still remains a challenge in periodontology. The aim of the present study was to examine the regenerative potential of a) different collagen support versus blank, b) different collagen support +/- a growth factor cocktail (GF) and c) a collagen powder versus collagen powder + periodontal ligament stem cells (PDLSCs) comparatively in a large animal model. The stem cells (SC) were isolated from extracted teeth of 15 adult miniature pigs. A total of 60 class II furcation defects were treated with the materials named above. Concluding, a histological evaluation followed. A significant increase in regeneration was observed in all treatment groups. The new attachment formation reached a maximum of 77 percent. In the control group a new attachment formation of 13 percent was observed. The study shows that all implanted materials improved periodontal regeneration, though there were no significant differences between the experimental groups. Within the limitations of this study, it can be assumed that the lack of significant differences is due to the complexity of the clinical setting.


Assuntos
Ligamento Periodontal/fisiologia , Regeneração/fisiologia , Células-Tronco/fisiologia , Animais , Cementogênese , Colágeno , Defeitos da Furca/terapia , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Ligamento Periodontal/citologia , Ligamento Periodontal/efeitos dos fármacos , Distribuição Aleatória , Regeneração/efeitos dos fármacos , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Suínos , Porco Miniatura , Tecidos Suporte
10.
Int J Syst Evol Microbiol ; 66(8): 3005-9, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27150727

RESUMO

A strain of obligately anaerobic, Gram-stain-negative and non-spore-forming rod-shaped bacterium was isolated from a human wound and characterized both phenotypically and genotypically. The strain was moderately saccharolytic and proteolytic. Phylogenetic analysis was based on full-length 16S rRNA gene sequence analysis and revealed the strain to represent a member of the genus Prevotella, but to be different from the described species, with the closest relationship to Prevotella bergensis and Prevotella multisaccharivorax. The genomic DNA G+C content was 43.2 mol%. The most abundant cellular long-chain fatty acids were 3-OH iso-C17 : 0, anteiso-C15 : 0 and iso-C15 : 0. In view of phenotypical and biochemical characteristics as well as gene sequencing, strain A1336T is considered to represent a novel species within the genus Prevotella, for which the name Prevotella colorans sp. nov. is proposed. The type strain is A1336T (=DSM 100333T =CCUG 67421T =CCOS 902T).


Assuntos
Filogenia , Prevotella/classificação , Ferimentos e Lesões/microbiologia , Idoso , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Feminino , Humanos , Pigmentação , Prevotella/genética , Prevotella/isolamento & purificação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
11.
Clin Oral Investig ; 20(1): 193-7, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26411858

RESUMO

OBJECTIVES: Co-occurrence of oral lichen planus (OLP) and chronic hepatitis C virus (HCV) infection suggests a strong association, but the relation between mucocutaneus, autoimmune lichen planus and HCV infection remains unclear. In areas with higher prevalence of HCV infection in general population, like Japan and southern Europe, 20 to 40 % of patients with OLP test positive for anti-HCV antibodies, whereas in German populations, a co-occurrence of 4.2 to 16 % was reported. MATERIAL AND METHODS: We screened 143 patients with histopathologically proven OLP for prevalence of anti-HCV antibodies. Additionally, we examined 51 anti-HCV-positive subjects with current or past HCV infection for clinical symptoms of OLP. In all patients, confirmatory diagnosis was made by the detection of HCV RNA via reverse transcription-polymerase chain reaction (RT-PCR). A randomized control group comprised 109 blood sera samples of patients without any characteristics of OLP. RESULTS: The results of all patients showed no co-occurrence in either cohort. CONCLUSION: In conclusion, no association between oral lichen planus and chronic HCV infection in our study population was found. CLINICAL RELEVANCE: Anti-HCV antibody screening in patients with confirmed oral lichen planus is not indicated routinely in central Germany.


Assuntos
Hepatite C/epidemiologia , Líquen Plano Bucal/epidemiologia , Estudos Transversais , Feminino , Alemanha/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Reação em Cadeia da Polimerase em Tempo Real
12.
Immunity ; 43(5): 1011-21, 2015 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-26588783

RESUMO

The skin is a site of constant dialog between the immune system and commensal bacteria. However, the molecular mechanisms that allow us to tolerate the presence of skin commensals without eliciting destructive inflammation are unknown. Using a model system to study the antigen-specific response to S. epidermidis, we demonstrated that skin colonization during a defined period of neonatal life was required for establishing immune tolerance to commensal microbes. This crucial window was characterized by an abrupt influx of highly activated regulatory T (Treg) cells into neonatal skin. Selective inhibition of this Treg cell wave completely abrogated tolerance. Thus, the host-commensal relationship in the skin relied on a unique Treg cell population that mediated tolerance to bacterial antigens during a defined developmental window. This suggests that the cutaneous microbiome composition in neonatal life is crucial in shaping adaptive immune responses to commensals, and disrupting these interactions might have enduring health implications.


Assuntos
Animais Recém-Nascidos/imunologia , Pele/imunologia , Pele/microbiologia , Infecções Estafilocócicas/imunologia , Staphylococcus epidermidis/imunologia , Linfócitos T Reguladores/imunologia , Animais , Animais Recém-Nascidos/microbiologia , Antígenos de Bactérias/imunologia , Interações Hospedeiro-Patógeno/imunologia , Tolerância Imunológica/imunologia , Inflamação/imunologia , Inflamação/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Microbiota/imunologia , Dados de Sequência Molecular , Infecções Estafilocócicas/microbiologia , Linfócitos T Reguladores/microbiologia
13.
Mol Microbiol ; 98(6): 1073-88, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26303846

RESUMO

Bacteria respond to ever-changing environments through several adaptive strategies. This includes mechanisms leading to a high degree of phenotypic variability within a genetically homogeneous population. In Staphylococcus aureus, the capsular polysaccharide (CP) protects against phagocytosis, but also impedes adherence to endothelial cells and/or matrix proteins. We analysed the regulation of core biosynthesis genes (capA-P) necessary for CP synthesis using single-cell assays (immunofluorescence and promoter-activity). In persistent human carriers, we found a distinct subpopulation of nasal S. aureus to be CP positive. In vitro, cap expression is also heterogeneous and strongly growth-phase dependent. We asked whether this peculiar expression pattern (earlyOff/lateHeterogen) is orchestrated by the quorum system Agr. We show that the Agr-driven effector molecule RNAIII promotes cap expression largely via inactivation of the repressor Rot. High NaCl, deletion of CodY or Sae also resulted in higher cap expression but did not change the earlyOFF/lateHeterogen expression pattern. Activity of the quorum system itself is largely homogenous and does not account for the observed heterogeneity of cap expression or the strictly growth phase dependent expression. Our findings are in contrast to the prevailing view that quorum sensing is the main driving force for virulence gene expression when bacterial cell densities increase.


Assuntos
Cápsulas Bacterianas/genética , Proteínas de Bactérias/genética , Fenótipo , Polissacarídeos Bacterianos/genética , Staphylococcus aureus/genética , Staphylococcus aureus/metabolismo , Cápsulas Bacterianas/química , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Humanos , Nariz/microbiologia , Polissacarídeos Bacterianos/biossíntese , Regiões Promotoras Genéticas , Percepção de Quorum , RNA Bacteriano/genética , Proteínas Repressoras/genética , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/crescimento & desenvolvimento , Staphylococcus aureus/patogenicidade , Virulência/genética
14.
J Antimicrob Chemother ; 70(5): 1322-30, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25583750

RESUMO

OBJECTIVES: Here we report on a long-term outbreak from 2009 to 2012 with an XDR Pseudomonas aeruginosa on two wards at a university hospital in southern Germany. METHODS: Whole-genome sequencing was performed on the outbreak isolates and a core genome was constructed for molecular epidemiological analysis. We applied a time-place-sequence algorithm to improve estimation of transmission probabilities. RESULTS: By using conventional infection control methods we identified 49 P. aeruginosa strains, including eight environmental isolates that belonged to ST308 (by MLST) and carried the metallo-ß-lactamase IMP-8. Phylogenetic analysis on the basis of a non-recombinant core genome that contained 22 outbreak-specific SNPs revealed a pattern of four dominant clades with a strong phylogeographic structure and allowed us to determine the potential temporal origin of the outbreak to July 2008, 1 year before the index case was diagnosed. Superspreaders at the root of clades exhibited a high number of probable and predicted transmissions, indicating their exceptional position in the outbreak. CONCLUSIONS: Our results suggest that the initial expansion of dominant sublineages was driven by a few superspreaders, while environmental contamination seemed to sustain the outbreak for a long period despite regular environmental control measures.


Assuntos
Surtos de Doenças , Farmacorresistência Bacteriana Múltipla , Infecções por Pseudomonas/epidemiologia , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/classificação , Pseudomonas aeruginosa/efeitos dos fármacos , Transmissão de Doença Infecciosa , Microbiologia Ambiental , Estudos Epidemiológicos , Genoma Bacteriano , Alemanha/epidemiologia , Hospitais Universitários , Humanos , Epidemiologia Molecular , Tipagem Molecular , Infecções por Pseudomonas/transmissão , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/isolamento & purificação , Análise de Sequência de DNA , Análise Espaço-Temporal
15.
J Oral Pathol Med ; 44(6): 429-36, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25213013

RESUMO

BACKGROUND: The aim of the study was the immunohistological assessment of VEGF-single nucleotide polymorphism (SNP)-related angiogenic activity in oral squamous cell carcinoma (OSCC) in correlation with prognosis. METHODS: Fifty OSCC samples were immunostained with CD31-antibodies. Mean microvessel density (MVD) and staining intensity were determined and associated with clinicopathological/prognostic features as well as with the VEGF +936C/T SNP. RESULTS: A significant higher MVD could be seen for T3 and T4 compared with T1 and T2, N > 0 vs. N0 as well as G3-G4 vs. G1-G2 OSCCs (all: P < 0.05). A higher MVD was also associated with increased and earlier rates of local relapses, more metastases, and a significant decreased overall as well as disease-free survival (all: P < 0.05). When comparing T1 and T2 samples with +936-T-allele with T 1&2 samples without this allele, staining intensity was significantly increased (P = 0.002). CONCLUSIONS: Angiogenesis influences local as well as distant growth of OSCCs with a significant correlation between prognostic parameters. The correlation between VEGF +936-T-allele and increased CD31 immunostain needs further confirmation.


Assuntos
Carcinoma de Células Escamosas/irrigação sanguínea , Carcinoma de Células Escamosas/genética , Neoplasias de Cabeça e Pescoço/irrigação sanguínea , Neoplasias de Cabeça e Pescoço/genética , Neoplasias Bucais/irrigação sanguínea , Neoplasias Bucais/genética , Fator A de Crescimento do Endotélio Vascular/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/patologia , Intervalo Livre de Doença , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Imuno-Histoquímica , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/patologia , Recidiva Local de Neoplasia/irrigação sanguínea , Recidiva Local de Neoplasia/genética , Segunda Neoplasia Primária/irrigação sanguínea , Segunda Neoplasia Primária/genética , Segunda Neoplasia Primária/patologia , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Polimorfismo de Nucleotídeo Único , Prognóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço , Taxa de Sobrevida
16.
Clin Oral Investig ; 19(2): 171-80, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25413495

RESUMO

OBJECTIVES: Oral anticoagulation therapy (OAT) with vitamin K inhibitors protects the patients from thromboembolic events. It may however lead to excessive hemorrhage during and after an oral surgery procedure. The aim of this systematic review was to evaluate the justifications to reduce, withdraw, or alter OATs prior to minor oral surgery procedures to manage bleeding events. MATERIALS AND METHODS: A systematic MEDLINE search was conducted for clinical studies in English or German language from 1994 to 2014 comparing patients treated with OAT, without OAT, as well as patients with altered OAT for oral surgery purposes. Relevant outcome parameters were: postoperative local hemostasis, bleeding episodes, occurrence of thromboembolic events, and other complications due to the anticoagulation medication. A hand search for references cited in the identified publications completed the review. RESULTS: After screening of 1755 abstracts, 16 clinical studies were identified according to the selection criteria. Due to the heterogeneity of the obtained data, aggregation and synthesis were not possible. There was no significant difference in bleeding events comparing patients under continued OAT to those with reduced, altered, and/or discontinued OAT medications. Minor bleeding events in the test and control groups were successfully stopped with local measures. However, no superiority of a single hemostatic measure could be identified. Neither the international normalized ratio (INR), within the therapeutic range (2-4), nor the extent of the minor oral surgery procedure had an influence on postoperative bleeding episodes. DISCUSSION: There is strong evidence that OAT patients undergoing minor oral surgery should not discontinue their medication in order to prevent thromboembolic complications. CLINICAL RELEVANCE: Nonetheless, INR should be less than 4, local hemostatic measures are of high importance and patients need to be instructed and closely monitored as minor bleedings might occur more often in OAT patients.


Assuntos
Anticoagulantes/uso terapêutico , Cirurgia Bucal , Humanos
17.
BMC Infect Dis ; 14: 650, 2014 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-25490897

RESUMO

BACKGROUND: This study aimed to investigate risk factors for colonisation with extensively drug-resistant P. aeruginosa (XDR-PA) in immunocompromised patients and to build a clinical risk score (CRS) based on these results. METHODS: We conducted a matched case-control study with 31 cases and 93 controls (1:3). Cases were colonised with XDR-PA during hospitalisation. Independent risk factors were determined using a three step conditional logistic regression procedure. A CRS was built with respect to the corresponding risk fraction of each risk factor, and its discriminatory power was estimated by receiver operating characteristic (ROC) analysis. RESULTS: The presence of a central venous catheter (OR 7.41, P = 0.0008), the presence of a urinary catheter (OR 21.04, P < 0.0001), CRP > 10 mg/dl (OR 7.36, P = 0.0015), and ciprofloxacin administration (OR 5.53, P = 0.025) were independent risk factors. The CRS exhibited a high discriminatory power, defining a high risk population with an approximately fourteen times greater risk for XDR-PA colonisation. CONCLUSIONS: Unnecessary use of antibiotics, particularly ciprofloxacin should be avoided, and a high standard of infection control measures must be achieved when using medical devices. A CRS can be used for adaptation of the active screening culture policy to the local setting.


Assuntos
Infecção Hospitalar/etiologia , Farmacorresistência Bacteriana Múltipla , Hospedeiro Imunocomprometido , Infecções por Pseudomonas/etiologia , Pseudomonas aeruginosa/isolamento & purificação , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Infecção Hospitalar/diagnóstico , Infecção Hospitalar/imunologia , Feminino , Doenças Hematológicas/complicações , Doenças Hematológicas/terapia , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Infecções por Pseudomonas/diagnóstico , Infecções por Pseudomonas/imunologia , Fatores de Risco
18.
Cell Microbiol ; 15(6): 891-909, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23217115

RESUMO

Staphylococcus (S.) aureus is a frequent cause of severe skin infections. The ability to control the infection is largely dependent on the rapid recruitment of neutrophils (PMN). To gain more insight into the dynamics of PMN migration and host-pathogen interactions in vivo, we used intravital two-photon (2-P) microscopy to visualize S. aureus skin infections in the mouse. Reporter S. aureus strains expressing fluorescent proteins were developed, which allowed for detection of the bacteria in vivo. By employing LysM-EGFP mice to visualize PMN, we observed the rapid appearance of PMN in the extravascular space of the dermis and their directed movement towards the focus of infection, which led to the delineation of an abscess within 1 day. Moreover, tracking of transferred labelled bone-marrow neutrophils showed that PMN localization to the site of infection is dependent on the presence of G-protein-coupled receptors on the PMN, whereas Interleukin-1 receptor was required on host cells other than PMN. Furthermore, the S. aureus complement inhibitor Ecb could block PMN accumulation at thesite of infection. Our results establish that 2-P microscopy is a powerful tool to investigate the orchestration of the immune cells, S. aureus location and gene expression in vivo on a single cell level.


Assuntos
Abscesso/patologia , Interações Hospedeiro-Patógeno/fisiologia , Microscopia/métodos , Fótons , Infecções Cutâneas Estafilocócicas/patologia , Staphylococcus aureus/fisiologia , Abscesso/fisiopatologia , Animais , Modelos Animais de Doenças , Corantes Fluorescentes , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Infiltração de Neutrófilos/fisiologia , Neutrófilos/patologia , Neutrófilos/fisiologia , Receptores de Interleucina-1/deficiência , Receptores de Interleucina-1/genética , Receptores de Interleucina-1/fisiologia , Transdução de Sinais/fisiologia , Pele/microbiologia , Pele/patologia , Pele/fisiopatologia , Infecções Cutâneas Estafilocócicas/fisiopatologia , Staphylococcus aureus/patogenicidade
19.
Artigo em Inglês | MEDLINE | ID: mdl-23159120

RESUMO

OBJECTIVES: Investigations of cone beam computed tomography (CBCT) for bisphosphonate-related osteonecrosis of the jaw (BRONJ) imaging are rare. The purpose of this study was to investigate the prevalence of typical radiological findings of BRONJ in CBCT. METHODS: Twenty-seven CBCTs of BRONJ sites were assessed on the basis of the radiological findings (cancellous bone destruction, cortical bone erosion, sequestration, osteosclerosis, and periostal bone formation) and put in relation to the severity of the BRONJ sites. RESULTS: Cancellous bone destruction and cortical bone erosion were the most common findings. Occurrence seems to decrease with decreasing BRONJ severity. Sequestration and osteosclerosis were less frequent and could be seen across all stages. Periosteal bone formation occurred in high-stage BRONJ only. CONCLUSION: Cancellous bone destruction, cortical bone erosion, sequestration, and osteosclerosis can be seen across all stages and prevalence seems to decrease with decreasing severity of BRONJ. The occurrence of periosteal new bone formation seems to start in high-stage BRONJ.


Assuntos
Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico/métodos , Feminino , Humanos , Masculino , Prevalência
20.
Microb Biotechnol ; 5(1): 129-34, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21958360

RESUMO

An intracellular approach for monitoring protein production in Staphylococcus aureus is described. mCherry, fused to the dodecapeptide Tip, was capable of inducing tetracycline repressor (TetR). Time- and concentration-dependent production of mCherry could be correlated to TetR-controlled GFPmut2 activity. This approach can potentially be extended to native S. aureus proteins.


Assuntos
Regulação Bacteriana da Expressão Gênica , Proteínas Luminescentes/metabolismo , Peptídeos/metabolismo , Staphylococcus aureus/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Expressão Gênica , Genes Reporter , Proteínas Luminescentes/genética , Peptídeos/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Staphylococcus aureus/genética , Tetraciclina/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA