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1.
Diagnostics (Basel) ; 13(13)2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37443639

RESUMO

Rapid testing for Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) of patients presenting to emergency departments (EDs) facilitates the decision for isolation on admission to hospital wards. Differences in the sensitivity of molecular assays have implications for diagnostic workflows. This study evaluated the performance of the cobas® Liat® RT-PCR, which is routinely used as the initial test for ED patients in our hospitals, compared with the eazyplex® RT-LAMP. A total of 378 oropharyngeal and nasal swabs with positive Liat® results were analysed. Residual sample aliquots were tested using NeuMoDx™, cobas® RT-PCR, and the eazyplex® assay. Patients were divided into asymptomatic (n = 157) and symptomatic (n = 221) groups according to the WHO case definition. Overall, 14% of positive Liat® results were not confirmed by RT-PCR. These samples were mainly attributed to 26.8% of asymptomatic patients, compared to 3.8% of the symptomatic group. Therefore, positive Liat® results were used to provisionally isolate patients in the ED until RT-PCR results were available. The eazyplex® assay identified 62% and 90.6% of RT-PCR-confirmed cases in asymptomatic and symptomatic patients, respectively. False-negative eazyplex® results were associated with RT-PCR Ct values > 30, and were more frequent in the asymptomatic group than in the symptomatic group (38.1% vs. 5.1%, respectively). Both the Liat® and eazyplex® assays are suitable for testing symptomatic patients. Their use in screening asymptomatic patients depends on the need to exclude any infection or identify those at high risk of transmission.

2.
Antibiotics (Basel) ; 12(6)2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-37370278

RESUMO

The acquisition of hypervirulence-associated genes by carbapenemase-producing Klebsiella pneumoniae is being increasingly observed, and easy-to-use diagnostic tests are needed for the surveillance of the hypervirulent K. pneumoniae (hvKp). In this pilot study, 87 K. pneumoniae isolates from invasive infections collected in 2022 and 2023 were analysed using the LAMP-based eazyplex® Superbug CRE and hvKp assays for the simultaneous identification of carbapenemases and virulence genes (rmpA/A2, iuC, iroC, ybt, clb). Nine isolates showed a Kleborate virulence score of 4 or 5 (10.3%). The time for the results of the eazyplex® assays ranged from 6.5 to 13 min, and the total turnaround time, including sample preparation, was less than 30 min. Five isolates, three of which produced New Delhi metallo-beta lactamase (NDM), were subjected to whole-genome sequencing (WGS) analysis for further characterisation. The eazyplex® test results for beta-lactamase and virulence genes were confirmed. The eazyplex® hvKp, currently only available as a Research Use Only assay, may be a useful tool for the rapid identification of hvKp without significant additional workload when combined with the eazyplex® Superbug CRE assay for the detection of carbapenemases.

3.
Antibiotics (Basel) ; 10(2)2021 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-33672690

RESUMO

Interest in the application of cold atmospheric plasma (CAP) in the medical field has been increasing. Indications in dentistry are surface modifications and antimicrobial interventions. The antimicrobial effect of CAP is mainly attributed to the generation of reactive oxygen and reactive nitrogen species. The aim of this article is to systematically review the available evidence from in-vitro studies on the antimicrobial effect of CAP on dental pathogens. A database search was performed (PubMed, Embase, Scopus). Data concerning the device parameters, experimental set-ups and microbial cultivation were extracted. The quality of the studies was evaluated using a newly designed assessment tool. 55 studies were included (quality score 31-92%). The reduction factors varied strongly among the publications although clusters could be identified between groups of set pathogen, working gases, and treatment time intervals. A time-dependent increase of the antimicrobial effect was observed throughout the studies. CAP may be a promising alternative for antimicrobial treatment in a clinically feasible application time. The introduced standardized protocol is able to compare the outcome and quality of in-vitro studies. Further studies, including multi-species biofilm models, are needed to specify the application parameters of CAP before CAP should be tested in randomized clinical trials.

4.
Antibiotics (Basel) ; 9(9)2020 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-32847029

RESUMO

(1) Background: Antimicrobial agents such as chlorhexidine (CHX) are commonly used in oral plaque control. However, sometimes those agents lack antimicrobial efficiency or cause undesired side effects. To identify alternative anti-infective agents, the present study investigated the antibacterial activity of all-fruit juices derived from blackcurrant, redcurrant, cranberry and raspberry on common oral pathogenic gram-positive and gram-negative bacteria (Streptococcus mutans, Streptococcus gordonii, Streptococcus sobrinus, Actinomyces naeslundii, Fusobacterium nucleatum, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Enterococcus faecalis). (2) Methods: Antibacterial efficiency was evaluated by agar diffusion assay and in direct contact with bacteria in planktonic culture. Furthermore, cytotoxicity on human gingival fibroblasts was determined. (3) Results: Blackcurrant juice was most efficient at suppressing bacteria; followed by the activity of redcurrant and cranberry juice. Raspberry juice only suppressed P. gingivalis significantly. Only high-concentrated blackcurrant juice showed minimal cytotoxic effects which were significantly less compared to the action of CHX. (4) Conclusion: Extracts from natural berry juices might be used for safe and efficient suppression of oral pathogenic bacterial species.

5.
Am J Orthod Dentofacial Orthop ; 156(6): 735-744, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31784007

RESUMO

INTRODUCTION: In this pilot study, we aimed to determine qualitative and quantitative microbiological changes after the implementation of orthodontic appliances. METHODS: A total of 10 healthy patients aged 12-15 years were recruited who needed to undergo orthodontic treatment with buccal fixed appliances. Gingival conditions were assessed by the Gingival Index, Periodontal Screening Index, and Sulcus Bleeding Index. Microbiological samples were collected before and 1 week after the start of therapy at premolars and molars of the right upper quadrant. Bacterial species were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. RESULTS: The total number of bacteria increased. Six bacterial species were identified that are involved in the development of caries and other infectious processes. The bacteria selectively adapted more efficiently to the new oral milieu compared with the general oral microbial background. There was a significant increase in Streptococcus spp at the premolars and molars. In all individuals, symptoms of inflammation and gingivitis were detected as a response to the bacterial challenge. CONCLUSIONS: Orthodontic treatment induces significant changes in the oral microbial flora associated with gingivitis and an enhanced risk for cariogenic reactions within the first days of orthodontic treatment. To prevent or reduce infectious side effects, oral hygiene instructions and control of patients are necessary before and during the beginning of the therapy.


Assuntos
Bactérias , Gengivite , Boca , Aparelhos Ortodônticos Fixos , Adolescente , Criança , Humanos , Boca/microbiologia , Aparelhos Ortodônticos , Índice Periodontal , Projetos Piloto
6.
Materials (Basel) ; 12(6)2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30875882

RESUMO

Coating of plasma chemical oxidized titanium (TiOB®) with gentamicin-tannic acid (TiOB® gta) has proven to be efficient in preventing bacterial colonization of implants. However, in times of increasing antibiotic resistance, the development of alternative antimicrobial functionalization strategies is of major interest. Therefore, the aim of the present study is to evaluate the antibacterial and biocompatible properties of TiOB® functionalized with silver nanoparticles (TiOB® SiOx Ag) and ionic zinc (TiOB® Zn). Antibacterial efficiency was determined by agar diffusion and proliferation test on Staphylocuccus aureus. Cytocompatibility was analyzed by direct cultivation of MC3T3-E1 cells on top of the functionalized surfaces for 2 and 4 d. All functionalized surfaces showed significant bactericidal effects expressed by extended lag phases (TiOB® gta for 5 h, TiOB® SiOx Ag for 8 h, TiOB® Zn for 10 h). While TiOB® gta (positive control) and TiOB® Zn remained bactericidal for 48 h, TiOB® SiOx Ag was active for only 4 h. After direct cultivation for 4 d, viable MC3T3-E1 cells were found on all surfaces tested with the highest biocompatibility recorded for TiOB® SiOx Ag. The present study revealed that functionalization of TiOB® with ionic zinc shows bactericidal properties that are comparable to those of a gentamicin-containing coating.

7.
Eur J Clin Microbiol Infect Dis ; 38(3): 581-591, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30680577

RESUMO

MALDI-TOF mass spectrometry (MS) may be used as a rapid typing method for nosocomial pathogens. Here, we evaluated MALDI-TOF MS for discrimination of hospital outbreak-related clusters of Serratia marcescens and carbapenemase-producing Citrobacter freundii. Thirty-three S. marcescens isolates collected from neonatal intensive care unit (NICU) patients, and 23 C. freundii isolates including VIM-positive isolates from a hospital colonization outbreak were measured by Vitek MS. Consensus spectra of each isolate were clustered using SARAMIS software. Genotyping was performed by whole-genome sequencing (WGS). First, a set of 21 S. marcescens isolates from 2014 with seven genotypes including three monoclonal clusters was used for the evaluation of MALDI-TOF typing. MS clustering was largely in agreement with genotyping results when the similarity cut-off for clonal identity was set on 90%. MALDI-TOF cluster analysis was then investigated for the surveillance of S. marcescens in the NICU in 2017 and demonstrated the introduction of new strains into the hospital and nosocomial transmissions. MS analysis of the C. freundii outbreak in 2016 revealed a monoclonal cluster of VIM-positive isolates and the separation of epidemiologically non-related VIM-positive and negative isolates. Two additional VIM-positive Citrobacter isolates from food samples were closely related to the large monoclonal cluster. WGS confirmed the MS results. MALDI-TOF MS may be used as a first-line typing tool for S. marcescens and C. freundii to detect transmission events in the hospital because isolates of an identical WGS type were grouped into the same MS cluster.


Assuntos
Técnicas de Tipagem Bacteriana/métodos , Citrobacter freundii/classificação , Infecção Hospitalar/microbiologia , Infecções por Enterobacteriaceae/microbiologia , Serratia marcescens/classificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Antibacterianos/farmacologia , Proteínas de Bactérias/biossíntese , Técnicas de Tipagem Bacteriana/normas , Citrobacter freundii/efeitos dos fármacos , Citrobacter freundii/isolamento & purificação , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/transmissão , Surtos de Doenças , Infecções por Enterobacteriaceae/epidemiologia , Infecções por Enterobacteriaceae/transmissão , Alemanha/epidemiologia , Humanos , Unidades de Terapia Intensiva Neonatal , Testes de Sensibilidade Microbiana , Serratia marcescens/efeitos dos fármacos , Serratia marcescens/isolamento & purificação , Sequenciamento Completo do Genoma , beta-Lactamases/biossíntese
8.
PLoS One ; 13(1): e0190716, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29304069

RESUMO

OBJECTIVE: From April 2013 to February 2014 we performed a multicentre prospective cross-sectional study in 541 German nursing home residents. We determined pharyngeal carriage of Streptococcus pneumoniae (primary objective) and other bacteria (secondary objective) in naso- and oropharyngeal swabs by culture-based standard procedures and explored the influence of multimorbidity and functional status on bacterial carriage. METHODS: Socio-demographic data, vaccination status, multimorbidity, nutrition and functional status defined by Comprehensive Geriatric Assessment were evaluated. We estimated carriage rates with 95% confidence intervals (CI) and explored potential risk factors by logistic regression analysis. RESULTS: Pneumococcal post-serotyping carriage rate was 0.8% (95%CI 0.2-1.9%; 4/526). Serotyping revealed serotypes 4, 7F, 23B and 23F and S. pseudopneumoniae in two other cases. Odds of carriage were higher in men (Odds ratio OR 5.3 (95%CI 0.9-29.4)), in malnourished residents (OR 4.6 (0.8-25.7)), residents living in shared rooms (OR 3.0 (0.5-16.5)) or having contact with schoolchildren (OR 2.0 (0.2-17.6)). The most frequent pathogen was Staphylococcus aureus (prevalence 29.5% (25.6-33.6%)) with meticillin-resistant Staphylococcus aureus prevalence of 1.1%. Gram-negative bacteria (GNB) were found in 22.5% (19.0-26.3%) with a prevalence of extended-spectrum beta lactamase (ESBL) producing bacteria of 0.8%. Odds of S. aureus carriage were higher for immobility (OR 1.84 (1.15-2.93)) and cognitive impairment (OR 1.54 (0.98-2.40)). Odds of GNB carriage were higher in residents with more severe comorbidity (OR 1.13 (1.00-1.28)) and malnutrition (OR 1.54 (0.81-2.91)). CONCLUSIONS: Given the observed data, at least long-term carriage of S. pneumoniae in nursing home residents seems to be rare and rather unlikely to cause nursing home acquired pneumonia. The low rate of colonization with multi drug resistant (MDR) bacteria confirms that nursing home residency is not a risk factor for MDR pneumonia in Germany. For individual risk assessment in this susceptible population, immobility and malnutrition should be considered as signs of functional impairment as well as comorbidity.


Assuntos
Portador Sadio/epidemiologia , Portador Sadio/microbiologia , Nariz/microbiologia , Casas de Saúde , Orofaringe/microbiologia , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Escherichia coli , Feminino , Alemanha , Humanos , Modelos Logísticos , Masculino , Multimorbidade , Prevalência , Estudos Prospectivos , Fatores de Risco , Staphylococcus aureus
9.
Z Gerontol Geriatr ; 51(4): 440-445, 2018 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-28956138

RESUMO

BACKGROUND: Nursing home residents and older hospitalized patients have a significantly higher risk to suffer from nosocomial infections (NI). It is still an unanswered question whether patients suffering from NI are at greater risk for deterioration of activities of daily living. MATERIAL AND METHODS: In a retrospective observational study, we evaluated the prevalence of NI during hospitalization of acute geriatric inpatients of the geriatric department at Jena University Hospital by patient records. The study included data from 555 patients, hospitalized from 1 August 2011 to 31 August 2012. We included patients without acute complications and those who developed NI after the second day of hospitalization. RESULTS: Every third patient developed a NI during the observation period. Consequently, the incidence of NI was approximately 18 patients with NI per 1000 days of hospitalization. This rate was considerably higher than the national average. The most frequent NIs were urinary tract infection, gastroenteritis and infections of the lower respiratory tract. A low value of Barthel index at admission, high multimorbidity index and transurethral indwelling catheters promoted the development of NI. An improvement in activities of daily living, assessed by mean values of the difference in the Barthel index, was significantly lower in patients who developed NI (mean value14.5 ± 16.3) than in patients who did not (mean value 18.1 ± 14.8). CONCLUSION: Nosocomial infections were a relevant factor for deterioration of the Barthel Index, at least temporarily and NIs, in particular the combination of several NIs, jeopardized an improvement in the activities of daily living. This was particularly true for infections of the lower respiratory tract and gastroenteritis.


Assuntos
Atividades Cotidianas , Infecção Hospitalar/epidemiologia , Gastroenterite/epidemiologia , Pacientes Internados/estatística & dados numéricos , Infecções Respiratórias/epidemiologia , Infecções Urinárias/epidemiologia , Doença Aguda , Idoso , Alemanha/epidemiologia , Humanos , Incidência , Prevalência , Estudos Retrospectivos , Fatores de Risco
10.
JMM Case Rep ; 4(6): e005099, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29026626

RESUMO

Introduction. Identification of non-O157 Shiga-toxin-producing Escherichia coli (STEC) infections may be underestimated in microbiological diagnosis. Case presentation. A 58-year-old woman developed diarrhoea with watery and subsequently mucous stool. Initial multiplex PCR testing revealed a positive result for stx2 . Culture isolation of a STEC was successful only after repeated inoculation of chromogenic E. coli media. Molecular characterization was performed and identified the isolate as stx2e-positive STEC of serotype O8 : H19. The strain harboured lpfA, but not eae. Conclusion. This case highlights the usefulness of initial multiplex PCR for diagnosis of non-O157 STEC infection.

11.
J Biophotonics ; 10(11): 1547-1557, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28464521

RESUMO

In times of rising antibiotic resistances, there is a high need for fast, sensitive and specific methods to determine antibiotic susceptibilities of bacterial pathogens. Here, we present an integrated microfluidic device in which bacteria from diluted suspensions are captured in well-defined regions using on-chip dielectrophoresis and further analyzed in a label-free and non-destructive manner using Raman spectroscopy. Minimal sample preparation and automated sample processing ensure safe handling of infectious material with minimal hands-on time for the operator. Clinical applicability of the presented device is demonstrated by antibiotic susceptibility testing of Escherichia coli towards the commonly prescribed second generation fluoroquinolone ciprofloxacin. Ciprofloxacin resistant E. coli were differentiated from sensitive E. coli with high accuracy within roughly three hours total analysis time paving the way for future point-of-care devices. Spectral changes leading to the discrimination between sensitive and resistant bacteria are in excellent agreement with expected metabolic changes in the bacteria due to the mode of action of the drug. The robustness of the method was confirmed with experiments involving different chip devices with different designs, both electrode as well as microfluidics design, and material. Furthermore, general applicability was demonstrated with different operators over an extended time period of half a year.


Assuntos
Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Dispositivos Lab-On-A-Chip , Análise Espectral Raman/instrumentação , Fatores de Tempo
13.
Med Microbiol Immunol ; 205(5): 485-500, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27377929

RESUMO

In cystic fibrosis (CF) patients' airways, inflammatory processes decisively contribute to remodeling and pulmonary destruction. The aims of this study were to compare upper airway (UAW) inflammation in the context of Staphylococcus aureus and Pseudomonas aeruginosa colonization in a longitudinal setting, and to examine further factors influencing UAW inflammation. Therefore, we analyzed soluble inflammatory mediators in noninvasively obtained nasal lavage (NL) of CF patients together with microbiology, medication, and relevant clinical parameters. NL, applying 10 mL of isotonic saline per nostril, was serially performed in 74 CF patients (326 samples). Concentrations of the inflammatory mediators' interleukin (IL)-1ß, IL-6, IL-8, matrix metalloproteinase (MMP)-9, and its anti-protease TIMP-1 were quantified by bead-based multiplexed assay, neutrophil elastase (NE) via ELISA. Culture-based microbiology of the upper and lower airways (LAW), as well as serological and clinical findings, were compiled. Our results indicate that UAW colonization with S. aureus significantly impacts the concentration of all measured inflammatory mediators in NL fluid except TIMP-1, whereas these effects were not significant for P. aeruginosa. Patients with S. aureus colonization of both the UAW and LAW showed significantly increased concentrations of IL-1ß, IL-6, IL-8, MMP-9, and slightly elevated concentrations of NE in NL fluid compared to non-colonized patients. This work elaborates a survey on S. aureus' virulence factors that may contribute to this underestimated pathology. Serial assessment of epithelial lining fluid by NL reveals that colonization of the UAW with S. aureus contributes more to CF airway inflammatory processes than hitherto expected.


Assuntos
Fibrose Cística/complicações , Inflamação/patologia , Infecções por Pseudomonas/patologia , Infecções Respiratórias/microbiologia , Infecções Respiratórias/patologia , Infecções Estafilocócicas/patologia , Adolescente , Adulto , Idoso , Criança , Fibrose Cística/patologia , Citocinas/análise , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Lavagem Nasal , Líquido da Lavagem Nasal/química , Peptídeo Hidrolases/análise , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/isolamento & purificação , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/isolamento & purificação , Adulto Jovem
14.
Front Microbiol ; 7: 357, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27047471

RESUMO

Secondary infections with Streptococcus pneumoniae cause severe pneumonia and enhance lethality during influenza epidemics and pandemics. Structural and functional similarities with viral neuraminidase (NA) suggest that the highly prevalent pneumococcal NAs, NanA and NanB, might contribute to this lethal synergism by supporting viral replication and that dual acting NA inhibitors (NAIs) will disrupt it. To verify this hypothesis, NanA and NanB were expressed in E. coli. After confirming their activity in enzyme assays, in vitro models with influenza virus A/Jena/8178/09 (Jena/8178) and the recombinant NanA or NanB (rNanA and rNanB) were established in A549 and MDCK cells to mimic the role of these pneumococcal NAs during co-infection. Studies on the influence of both NAs on viral receptor expression, spread, and yield revealed a distinct effect of NanA and NanB on viral replication in these in vitro models. Both enzymes were able to support Jena/8178 replication at certain concentrations. This synergism was disrupted by the NAIs oseltamivir, DANA, katsumadain A, and artocarpin exerting an inhibitory effect on viral NA and NanA. Interestingly, katsumadain A and artocarpin inhibited rNanA and rNanB similarly. Zanamivir did not show activity. These results demonstrate a key role of pneumococcal NAs in the lethal synergism with influenza viruses and reveal opportunities for its effective disruption.

16.
Diagn Microbiol Infect Dis ; 84(3): 252-7, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26712265

RESUMO

Rapid diagnosis of bloodstream infections remains a challenge for the early targeting of an antibiotic therapy in sepsis patients. In recent studies, the reliability of the Nanosphere Verigene Gram-positive and Gram-negative blood culture (BC-GP and BC-GN) assays for the rapid identification of bacteria and resistance genes directly from positive BCs has been demonstrated. In this work, we have developed a model to define treatment recommendations by combining Verigene test results with knowledge on local antibiotic resistance patterns of bacterial pathogens. The data of 275 positive BCs were analyzed. Two hundred sixty-three isolates (95.6%) were included in the Verigene assay panels, and 257 isolates (93.5%) were correctly identified. The agreement of the detection of resistance genes with subsequent phenotypic susceptibility testing was 100%. The hospital antibiogram was used to develop a treatment algorithm on the basis of Verigene results that may contribute to a faster patient management.


Assuntos
Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bacteriemia/tratamento farmacológico , Bacteriemia/microbiologia , Farmacorresistência Bacteriana , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Algoritmos , Bacteriemia/diagnóstico , Bactérias Gram-Negativas/classificação , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/genética , Bactérias Gram-Positivas/classificação , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/genética , Humanos , Testes de Sensibilidade Microbiana , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
17.
Rhinology ; 53(3): 249-59, 2015 09.
Artigo em Inglês | MEDLINE | ID: mdl-26363166

RESUMO

BACKGROUND: Chronic bacterial rhinosinusitis is a common feature in Cystic fibrosis (CF) as mucociliary clearance in the sinonasal compartment is impaired. Aim of the present prospective study was to compare dynamics of inflammatory markers in the upper and lower airways (UAW/LAW) during systemic antibiotic therapy. METHODS: Nasal lavage and sputum of 16 CF-patients receiving an IV-antibiotic treatment against Pseudomonas aeruginosa and/ or Staphylococcus aureus were collected before and during treatment (median after 7.5 days). Cytological changes, DNA concentration, and inflammatory markers interleukin (IL)-4, IL-8, IL-13 and Myeloperoxidase (MPO) were assessed in samples from both airway compartments. RESULTS: Total cell count declined significantly in LAW-samples but not in UAW. Although MPO and IL-8 decreased significantly in both airway compartments, this was considerably more pronounced for LAW (median decrease MPO: LAW=9.8-fold vs UAW=1.75-fold, respectively; IL-8: LAW=3-fold vs UAW=1.9-fold, respectively). DISCUSSION: This is the first publication demonstrating substantially lower effects of IV-antibiotic treatment on sinonasal than on pulmonary inflammatory markers. Consequently, our findings highlight limitations of systemic antibiotic treatment to control infection in the sinonasal compartment. Primarily, we attribute this to the paranasal sinus ́ structure: these hollow organs, which in bacterial sinusitis are frequently filled with pus, mucoeceles and polyps, are not reached effectively by systemic antibiotic treatment.


Assuntos
Antibacterianos/uso terapêutico , Fibrose Cística/metabolismo , Pneumonia/tratamento farmacológico , Pneumonia/metabolismo , Infecções por Pseudomonas/tratamento farmacológico , Infecções Estafilocócicas/tratamento farmacológico , Adulto , Biomarcadores/metabolismo , Fibrose Cística/complicações , Fibrose Cística/tratamento farmacológico , Citocinas/metabolismo , Feminino , Humanos , Infusões Intravenosas , Masculino , Estudos Prospectivos , Infecções por Pseudomonas/metabolismo , Infecções por Pseudomonas/patologia , Pseudomonas aeruginosa , Rinite/tratamento farmacológico , Rinite/metabolismo , Rinite/microbiologia , Sinusite/tratamento farmacológico , Sinusite/metabolismo , Sinusite/microbiologia , Infecções Estafilocócicas/metabolismo , Infecções Estafilocócicas/patologia , Staphylococcus aureus , Adulto Jovem
18.
Biomicrofluidics ; 9(4): 044118, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26339318

RESUMO

This work presents a polymeric centrifugal microfluidic platform for the rapid and sensitive identification of bacteria directly from urine, thus eliminating time-consuming cultivation steps. This "Lab-on-a-Disc" platform utilizes the rotationally induced centrifugal field to efficiently capture bacteria directly from suspension within a glass-polymer hybrid chip. Once trapped in an array of small V-shaped structures, the bacteria are readily available for spectroscopic characterization, such as Raman spectroscopic fingerprinting, providing valuable information on the characteristics of the captured bacteria. Utilising fluorescence microscopy, quantification of the bacterial load has been achieved for concentrations above 2 × 10(-7) cells ml(-1) within a 4 µl sample. As a pilot application, we characterize urine samples from patients with urinary tract infections. Following minimal sample preparation, Raman spectra of the bacteria are recorded following centrifugal capture in stopped-flow sedimentation mode. Utilizing advanced analysis algorithms, including extended multiplicative scattering correction, high-quality Raman spectra of different pathogens, such as Escherichia coli or Enterococcus faecalis, are obtained from the analyzed patient samples. The whole procedure, including sample preparation, requires about 1 h to obtain a valuable result, marking a significant reduction in diagnosis time when compared to the 24 h and more typically required for standard microbiological methods. As this cost-efficient centrifugal cartridge can be operated using low-complexity, widely automated instrumentation, while providing valuable bacterial identification in urine samples in a greatly reduced time-period, our opto-microfluidic Lab-on-a-Disc device demonstrates great potential for next-generation patient diagnostics at the of point-of-care.

19.
Anal Bioanal Chem ; 407(27): 8343-52, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26231687

RESUMO

Vancomycin is an important glycopeptide antibiotic which is used to treat serious infections caused by Gram-positive bacteria. However, during the last years, a tremendous rise in vancomycin resistances, especially among Enterococci, was reported, making fast diagnostic methods inevitable. In this contribution, we apply Raman spectroscopy to systematically characterize vancomycin-enterococci interactions over a time span of 90 min using a sensitive Enterococcus faecalis strain and two different vancomycin concentrations above the minimal inhibitory concentration (MIC). Successful action of the drug on the pathogen could be observed already after 30 min of interaction time. Characteristic spectral changes are visualized with the help of multivariate statistical analysis (linear discriminant analysis and partial least squares regressions). Those changes were employed to train a statistical model to predict vancomycin treatment based on the Raman spectra. The robustness of the model was tested using data recorded by an independent operator. Classification accuracies of >90 % were obtained for vancomycin concentrations in the lower range of a typical trough serum concentration recommended for most patients during appropriate vancomycin therapy. Characterization of drug-pathogen interactions by means of label-free spectroscopic methods, such as Raman spectroscopy, can provide the knowledge base for innovative and fast susceptibility tests which could speed up microbiological analysis as well as finding applications in novel antibiotic screenings assays. Graphical Abstract E. faecalis is incubated with vancomycin and characterized by means of Raman spectroscopy after different time points. Characteristic spectral changes reveal efficient vancomycin-enterococci-interaction.


Assuntos
Antibacterianos/farmacologia , Enterococcus faecalis/efeitos dos fármacos , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Testes de Sensibilidade Microbiana/métodos , Análise Espectral Raman/métodos , Vancomicina/farmacologia , Humanos
20.
Mediators Inflamm ; 2015: 626530, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26185365

RESUMO

BACKGROUND: In cystic fibrosis (CF) the upper (UAW) and lower airways (LAW) are reservoirs for pathogens like Pseudomonas aeruginosa. The consecutive hosts' release of proteolytic enzymes contributes to inflammation and progressive pulmonary destruction. Objectives were to assess dynamics of protease : antiprotease ratios and pathogens in CF-UAW and LAW sampled by nasal lavage (NL) and sputum before and after intravenous- (IV-) antibiotic therapy. METHODS: From 19 IV-antibiotic courses of 17 CF patients NL (10 mL/nostril) and sputum were collected before and after treatment. Microbiological colonization and concentrations of NE/SLPI/CTSS (ELISA) and MMP-9/TIMP-1 (multiplex bead array) were determined. Additionally, changes of sinonasal symptoms were assessed (SNOT-20). RESULTS: IV-antibiotic treatment had more pronounced effects on inflammatory markers in LAW, whereas trends to decrease were also found in UAW. Ratios of MMP-9/TIMP-1 were higher in sputum, and ratios of NE/SLPI were higher in NL. Remarkably, NE/SLPI ratio was 10-fold higher in NL compared to healthy controls. SNOT-20 scores decreased significantly during therapy (P = 0.001). CONCLUSION: For the first time, changes in microbiological patterns in UAW and LAW after IV-antibiotic treatments were assessed, together with changes of protease/antiprotease imbalances. Delayed responses of proteases and antiproteases to IV-antibiotic therapy were found in UAW compared to LAW.


Assuntos
Antibacterianos/administração & dosagem , Fibrose Cística/tratamento farmacológico , Pseudomonas aeruginosa/isolamento & purificação , Inibidor Tecidual de Metaloproteinase-1/análise , Adolescente , Adulto , Estudos de Casos e Controles , Catepsinas/análise , Criança , Fibrose Cística/enzimologia , Fibrose Cística/microbiologia , Feminino , Humanos , Injeções Intravenosas , Elastase de Leucócito/análise , Masculino , Metaloproteinase 9 da Matriz/análise , Pessoa de Meia-Idade , Estudos Prospectivos , Inibidor Secretado de Peptidases Leucocitárias/análise , Escarro/microbiologia
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