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1.
Vaccine ; 40(50): 7335-7342, 2022 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-36347722

RESUMO

BACKGROUND AND OBJECTIVES: Although vaccine preventable, the incidence of tick-borne encephalitis (TBE) increased in Germany from 2001 to 2021 by on average 2% each year, with a peak of more than 700 TBE infections documented in 2020. TBE-risk areas, as designated by district based on incidence of human cases, expanded north- and northeastward, present in 11 of the 16 Federal States as of 2022. Using claims data from a German statutory health insurance in the Federal States of Saxony and Thuringia (AOK PLUS), we aimed to assess whether official assignment of a district to a risk area had an impact on vaccination rates in Germany. METHODS: The data covered the period from 01/01/2010 to 31/12/2018 and included information on vaccine administrations from outpatient physicians. Yearly incident vaccination rates were reported overall and by district. To investigate the association between a new designation of an incident TBE-risk area and vaccination rates, a difference-in-difference analysis was conducted. RESULTS: Overall, the incident vaccination rates increased from 6.2 to 9.5 per 1,000 person-years between 2012 and 2018, with a peak of 12.2 in 2015. While districts that had been risk-areas for the whole study period had always a higher vaccination rate compared to districts that were never categorized as risk areas, the increase between 2012 and 2018 was comparable in the two groups (3.0 and 3.2 per 1,000 person-years, respectively). In contrast, districts that were newly designated risk districts during the study period experienced a significantly larger increase in vaccination rates, going from 5.8 to 14.7 per 1,000 person-years between 2012 and 2018, with a peak of 19.6 in 2015. CONCLUSION: The results suggest that the new designation of a district as risk area has a significant positive impact on vaccination rates, which is strongest immediately after designation of risk area.


Assuntos
Encefalite Transmitida por Carrapatos , Encefalite Viral , Infecções por Flavivirus , Vacinas , Humanos , Cobertura Vacinal , Encefalite Transmitida por Carrapatos/epidemiologia , Encefalite Transmitida por Carrapatos/prevenção & controle , Fatores de Transcrição
2.
Infection ; 43(1): 37-43, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25367409

RESUMO

INTRODUCTION: Tigecycline is an established treatment option for infections with multiresistant bacteria (MRB). It retains activity against many strains with limited susceptibility to other antibiotics. Efficacy and safety of tigecycline as monotherapy or in combination regimens were investigated in a prospective noninterventional study involving 1,025 severely ill patients in clinical routine at 137 German hospitals. MATERIALS AND METHODS: Data on the full population have been published; our present analysis focuses on infections caused by MRB. The study population included patients with complicated infections, high disease severity (APACHE II > 15: 65 %) and high MRB prevalence. Most patients had comorbidities, including cardiovascular disease, renal insufficiency, and/or diabetes mellitus. Treatment success was defined as cure/improvement without requirement of further antibiotic therapy. RESULTS: Pathogens isolated from 215 evaluable patients with documented MRB infections included 132 methicillin-resistant Staphylococcus aureus (MRSA), 42 vancomycin-resistant Enterococci (VRE) and 67 Gram-negative extended beta-lactamase (ESBL) producers. Of the MRB subpopulation, 140 patients received tigecycline monotherapy, 75 were treated with combination regimens. High overall clinical success rates were recorded for MRB infections treated with tigecycline alone (94 %) or in combinations (88 %); in detail intraabdominal infections (monotherapy: 90 %; combinations: 93 %), skin/soft tissue infections (93; 100 %), community-acquired pneumonia (100; 100 %), hospital-acquired pneumonia (94,7; 72,7 %), diabetic foot infections (89; 33 %), blood stream infections (100; 100 %) and multiple-site infections (92; 71 %). CONCLUSIONS: Tigecycline achieved high clinical success rates in patients with documented infections involving MRB strains despite high disease severity. These results add to the evidence indicating that tigecycline is a valuable therapeutic option for complicated infections in severely ill patients with a high likelihood of multidrug-resistant pathogen involvement.


Assuntos
Antibacterianos/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/microbiologia , Farmacorresistência Bacteriana Múltipla , Minociclina/análogos & derivados , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/administração & dosagem , Antibacterianos/farmacologia , Infecções Bacterianas/epidemiologia , Pé Diabético , Quimioterapia Combinada , Feminino , Hospitalização , Humanos , Infecções Intra-Abdominais , Masculino , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Pessoa de Meia-Idade , Minociclina/administração & dosagem , Minociclina/farmacologia , Minociclina/uso terapêutico , Estudos Prospectivos , Tigeciclina , Resultado do Tratamento , Enterococos Resistentes à Vancomicina/efeitos dos fármacos , Adulto Jovem , beta-Lactamases
3.
Hautarzt ; 65(1): 15-25, 2014 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-24445941

RESUMO

Staphylococcus aureus is one of the major pathogens causing chronic skin and soft tissue infections. Particularly isolates producing Panton-Valentine leukocidin (PVL) comprising methicillin-susceptible and community-associated methicillin-resistant S. aureus (CA-MRSA) have been associated with more aggressive and persistent or relapsing courses. Beyond classical resistance mechanisms, functional resistance as shown by the small colony-variant (SCV) phenotype could be also responsible for treatment failures, despite the administration of antibiotics tested in vitro as susceptible. Also this phenotype has been associated with chronic courses of infections often with multiple exacerbations. Due to their ability to persist intracellularly, SCVs are protected from host defense and antibiotic treatment if only extracellularly active agents are administered. Reduced growth, abnormal colony morphology and changes in the metabolism of the SCVs aggravate drastically their identification, differentiation and susceptibility testing. The diagnostic and therapeutic challenges of PVL-positive and SCV isolates necessitate close collaboration with microbiological and infectious disease specialists.


Assuntos
Toxinas Bacterianas/metabolismo , Exotoxinas/metabolismo , Leucocidinas/metabolismo , Infecções dos Tecidos Moles/diagnóstico , Infecções dos Tecidos Moles/microbiologia , Infecções Cutâneas Estafilocócicas/diagnóstico , Infecções Cutâneas Estafilocócicas/microbiologia , Staphylococcus aureus/isolamento & purificação , Staphylococcus aureus/metabolismo , Antibacterianos/uso terapêutico , Doença Crônica , Humanos , Recidiva , Infecções dos Tecidos Moles/tratamento farmacológico , Infecções Cutâneas Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/classificação
4.
Clin Microbiol Infect ; 20(9): O554-7, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24372797

RESUMO

We analysed trends in antimicrobial non-susceptibility in methicillin-resistant Staphylococcus aureus (MSRA) from Germany to assess the impact of the changing population structure of MRSA on antimicrobial resistance rates. During two large nationwide multicentre studies in 2004-2005 and 2010-2011, we collected consecutively spa-genotyped MRSA isolates. The increase in non-susceptibility rates for tetracycline and trimethoprim-sulphamethoxazole was associated with the spread of livestock-associated MRSA. A decrease in non-susceptibility rates for aminoglycosides and quinolones affected all major lineages (spa-clonal complexes 003, 008, and 032). All isolated remained susceptible to glycopeptides and linezolid.


Assuntos
Antibacterianos/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Genótipo , Alemanha/epidemiologia , Humanos , Staphylococcus aureus Resistente à Meticilina/classificação , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana , Tipagem Molecular
5.
Eur J Clin Microbiol Infect Dis ; 30(9): 1095-103, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21347680

RESUMO

To document the development of resistance to tigecycline in comparison with 17 other antimicrobials, the susceptibilities of 2,741 isolates comprising 16 bacterial species recovered from hospitalised patients in 15 German centres in 2009 were assessed. The results were compared with those of previous trials (German Tigecycline Evaluation Surveillance Trial, G-TEST I and II, performed in 2005 and 2007, respectively) conducted prior to and shortly after the introduction of tigecycline in Germany. Moreover, the in vitro activities of tigecycline against the subset of multidrug-resistant (MDR) pathogens recovered within all three sampling periods (n = 4,988) were evaluated in comparison to the corresponding non-MDR isolates. All susceptibility tests were performed by broth microdilution. Between 2005 and 2009, tigecycline retained its high activity against Gram-positive and Gram-negative organisms, including MDR pathogens. By contrast, an in part marked increase in resistance to broad-spectrum beta-lactams and fluoroquinolones was observed for many Enterobacteriaceae and for non-fermenting Gram-negative bacteria. Against a background of a steadily increasing number of multiresistant pathogens, the activity of tigecycline remained unaltered. With the exception of Acinetobacter isolates with decreased susceptibility to carbapenems, tigecycline's activity profile was not notably affected by organisms resistant to other drug classes and, thus, holds promise as an important therapeutic agent, particularly for situations in which MDR organisms are suspected.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla , Bactérias Gram-Negativas/efeitos dos fármacos , Infecções por Bactérias Gram-Negativas/microbiologia , Bactérias Gram-Positivas/efeitos dos fármacos , Infecções por Bactérias Gram-Positivas/microbiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Alemanha , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/isolamento & purificação , Humanos , Lactente , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Minociclina/análogos & derivados , Minociclina/farmacologia , Tigeciclina , Adulto Jovem
6.
Allergy ; 65(11): 1430-7, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20456313

RESUMO

BACKGROUND: Staphylococcus aureus has been associated with chronic rhinosinusitis with nasal polyps (CRSwNP) pathogenesis but its role is still controversially discussed. Here, we demonstrate S. aureus detection in the mucosa of CRSwNP. In addition, intracellular residency of S. aureus in nasal polyp epithelial cells (NPECs) and its capability to induce TH-2 cytokines were analyzed in vitro. METHODS: Staphylococcus aureus detection in CRSwNP (n = 25), CRS without polyps (CRSsNP, n = 5), and turbinate mucosa (TM, n = 10) was performed by peptide nucleic acid-fluorescence in situ hybridization (PNA-FISH) and microbial cultivation from tissue biopsies. Intracellular residency was examined by intracellular persistence assay and electron microscopy. IL-6 and IL-13 responses to S. aureus infection and supernatants were quantified by ELISA. RESULTS: Peptide nucleic acid-fluorescence in situ hybridization positive bacterial cells were significantly increased in the epithelium of CRSwNP (17/25) compared to CRSsNP (0/5) and TM (1/10). Good concordance of PNA-FISH results and S. aureus cultivation was found applying Cohen's κ for CRSwNP (κ = 0.841) and TM (κ = 1.0). Intracellular persistence assay with S. aureus strain Newman and its corresponding small-colony variant mutant strain III33 demonstrated intracellular survival and replication of S. aureus within NPECs. Both S. aureus strains significantly induced IL-6 but not IL-13 in infected NPECs and in NPECs challenged with corresponding staphylococcal supernatants. CONCLUSION: Invasion of the epithelium by S. aureus was a phenomenon seen predominantly in CRSwNP. Regardless of an intra- or extracellular localization in the epithelium, S. aureus is capable to induce IL-6 synthesis in vitro and thus may contribute to the TH-2 cytokine pattern in CRSwNP.


Assuntos
Interleucina-6/biossíntese , Mucosa Nasal/microbiologia , Pólipos Nasais/microbiologia , Rinite/microbiologia , Sinusite/microbiologia , Infecções Estafilocócicas/complicações , Adulto , Células Cultivadas , Doença Crônica , Feminino , Humanos , Hibridização in Situ Fluorescente , Interleucina-13/biossíntese , Masculino , Pessoa de Meia-Idade , Mucosa Nasal/imunologia , Pólipos Nasais/complicações , Pólipos Nasais/imunologia , Rinite/complicações , Rinite/imunologia , Sinusite/complicações , Sinusite/imunologia , Infecções Estafilocócicas/imunologia , Staphylococcus aureus/imunologia
7.
Eur J Clin Microbiol Infect Dis ; 28(8): 1007-11, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19296137

RESUMO

Tigecycline, a broad-spectrum antibiotic for parenteral use, was introduced in Germany in May 2006. In the G-TEST-II trial, the susceptibility of isolates, recovered in 2007 from hospitalised patients in 15 centres, was assessed against tigecycline and comparators. Susceptibility tests were performed by the microdilution procedure. This study reports on the susceptibility of the isolates of 16 bacterial species and compares the results with those of a trial (G-TEST I) conducted prior to the introduction of tigecycline. Between 2005 and 2007, tigecycline retained activity against Gram-positive and Gram-negative organisms. By contrast, the rate of vancomycin-resistant strains among Enterococcus faecium isolates almost doubled. Moreover, an increase in resistance to broad-spectrum beta-lactams and fluoroquinolones was observed for members of the family Enterobacteriaceae. Against a background of a steadily rising number of pathogens that are resistant to various antibiotic classes, tigecycline represents an important treatment option.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Infecções Bacterianas/microbiologia , Minociclina/análogos & derivados , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Bactérias/isolamento & purificação , Criança , Pré-Escolar , Feminino , Alemanha , Hospitais , Humanos , Lactente , Masculino , Testes de Sensibilidade Microbiana/métodos , Pessoa de Meia-Idade , Minociclina/farmacologia , Tigeciclina , Adulto Jovem
8.
Eur J Clin Microbiol Infect Dis ; 28(8): 935-43, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19319582

RESUMO

In developed countries, acute gastroenteritis (AGE) is a major source of morbidity. However, only a few studies have estimated its incidence and the associated medical burden. This population-based study determined the incidence of community-acquired AGE patients seeking medical care and the relative role of various pathogens. Stool samples from patients with AGE presenting to a general practitioner (GP), pediatrician, or specialist in internal medicine for that reason were screened for various bacterial and viral enteropathogens. A control group was established as well. Incidences were calculated by the number of positive patients divided by the general population. The study was performed in north-west Germany in 2004. The incidence of AGE patients requiring medical consultation was 4,020/100,000 inhabitants. Children (<5 years of age) were at the highest risk (13,810/100,000 inhabitants). Of the patients, 6.6% were tested positive for an enteropathogenic bacteria and 17.7% for a viral agent. The predominant pathogens were norovirus (626/100,000) and rotavirus (270/100,000). Salmonella was the most frequently detected bacteria (162/100,000). The results presented confirm AGE and, specifically, AGE of viral origin as a major public health burden in developed countries.


Assuntos
Infecções Comunitárias Adquiridas/epidemiologia , Gastroenterite/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Bactérias/classificação , Bactérias/isolamento & purificação , Criança , Pré-Escolar , Infecções Comunitárias Adquiridas/etiologia , Fezes/microbiologia , Fezes/virologia , Feminino , Gastroenterite/etiologia , Alemanha/epidemiologia , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Vírus/classificação , Vírus/isolamento & purificação , Adulto Jovem
9.
J Hosp Infect ; 71(4): 320-6, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19201056

RESUMO

Since patient exchange between hospitals sharing a common catchment area might favour regional spread of meticillin-resistant Staphylococcus aureus (MRSA), the reliable detection of patients colonised at admission is crucial. Thus, hospitals in the Dutch-German border area EUREGIO MRSA-net aim at synchronising their local MRSA standards in order to prevent unidentified inter-hospital as well as cross-border spread. This assumes enhanced knowledge of MRSA prevalence and risk factors associated with MRSA carriage at admission. We conducted nasal MRSA screening of all inpatients admitted to 39 German hospitals (in the period 1 November to 30 November 2006) and to one Dutch hospital (in the period 1 July to 30 September 2007) in the EUREGIO MRSA-net. A total of 390 MRSA cases were detected among 25,540 patients screened. The admission prevalence was 1.6 MRSA/100 patients (6.5% of all S. aureus) in the German and 0.5 MRSA/100 patients (1.4% of all S. aureus) in the Dutch part of the border region. Overall, the predominating S. aureus protein A gene (spa) sequence types were t003, t032 and t011. One isolate (t044) carried Panton-Valentine leukocidin (PVL) encoding genes. Altogether, 79% and 67% of all MRSA patients in the German and Dutch regions respectively, were identifiable by the classical nosocomial risk factors assessed. In patients lacking all risk factors assessed, spa types t011 and t034 were predominant (P<0.001).


Assuntos
Técnicas de Tipagem Bacteriana , Portador Sadio/epidemiologia , Staphylococcus aureus Resistente à Meticilina/classificação , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Infecções Estafilocócicas/epidemiologia , Toxinas Bacterianas/genética , Portador Sadio/microbiologia , DNA Bacteriano/química , DNA Bacteriano/genética , Exotoxinas/genética , Genótipo , Alemanha/epidemiologia , Hospitais , Humanos , Leucocidinas/genética , Países Baixos/epidemiologia , Nariz/microbiologia , Admissão do Paciente , Prevalência , Análise de Sequência de DNA , Infecções Estafilocócicas/microbiologia , Proteína Estafilocócica A/genética
10.
Eur J Clin Microbiol Infect Dis ; 28(1): 83-90, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18716808

RESUMO

Tigecycline is a novel antimicrobial agent for parenteral use encompassing a broad spectrum of bacterial pathogens, including multi-resistant organisms. Here, we report the results of the first nationwide surveillance trial that was conducted in order to evaluate the susceptibility of bacterial isolates to tigecycline in a European country prior to its clinical use. A total of 2,610 Gram-positive and Gram-negative organisms recovered from hospitalized patients were tested. Minimum inhibitory concentrations (MICs) were determined using the microdilution method. All enterococci, staphylococci (including methicillin-resistant Staphylococcus aureus; MRSA), and streptococci tested were tigecycline-susceptible, except one isolate of Staphylococcus haemolyticus. Among the Gram-negative bacteria, 100% of the Escherichia coli isolates (including extended spectrum beta-lactamase [ESBL]-producers) were tigecycline-susceptible, while about 10% of the Enterobacter cloacae and Klebsiella pneumoniae isolates were resistant. Based on the results of this surveillance study, tigecycline may represent a suitable option most notably for the empiric treatment of bacterial mixed infections, including in clinical situations in which multi-resistant organisms are suspected.


Assuntos
Antibacterianos/farmacologia , Bactérias Aeróbias/efeitos dos fármacos , Infecções Bacterianas/microbiologia , Minociclina/análogos & derivados , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Bactérias Aeróbias/isolamento & purificação , Criança , Pré-Escolar , Feminino , Alemanha , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/isolamento & purificação , Humanos , Lactente , Recém-Nascido , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Minociclina/farmacologia , Tigeciclina
11.
J Inflamm (Lond) ; 5: 11, 2008 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-18664275

RESUMO

OBJECTIVES: Chronic rhinosinusitis (CRS) is a chronic inflammatory disease of the nasal mucosa. Recent studies suggest that S. aureus enterotoxins may play an etiologic role in the development of CRS. Apart from surgery and repeated courses of steroids, macrolide antibiotics have been reported to exert anti-inflammatory effects in CRS. Similar effects have been reported for fluoroquinolones on various cell types. Since these effects have poorly been characterized in CRS, we examined anti-inflammatory effects of ciprofloxacin on human nasal epithelial cells (HNECs). METHODS: Inflammation was induced in HNECs cultured from nasal turbinate mucosa with supernatants of S. aureus Newman for 12 hours. Subsequently, HNECs were coincubated with S. aureus Newman and ciprofloxacin (1.5 x 10-5 M), clarithromycin (10-6 M) or prednisolone (10-5 M) for another 12 hours. IL-8 synthesis was quantified after 12 and 24 hours by ELISA. RESULTS: Stimulation with S. aureus Newman supernatants was associated with an increase of IL-8 synthesis after 12 hours in all experiments. During the second 12 hours, IL-8 synthesis decreased and this effect was independent from any stimulus or inhibitor. However, coincubation of HNECs with ciprofloxacin was associated with a more extensive decrease of IL-8 synthesis. Similarly, addition of clarithromycin was associated with a reduction of IL-8 synthesis although this effect was not significant. Coincubation with prednisolone resulted in a significant reduction of IL-8 levels. CONCLUSION: Ciprofloxacin exerts anti-inflammatory effects in S. aureus Newman driven nasal inflammation. Inhibitory effects were comparable to those of prednisolone and clarithromycin.

12.
Scand J Immunol ; 67(3): 238-44, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18261038

RESUMO

Citrobacter rodentium induces an acute, self-limited colitis in mice which is histologically associated with crypt hyperplasia. The infection serves as a model for human infectious colitis induced by enteropathogenic Escherichia coli. We investigated if Balb/c mice, which had spontaneously cleared C. rodentium infection, were protected against re-infection and if resistance against intestinal infection can be systemically transferred using spleen cells. The course of infection was monitored by faecal excretion. Spleen cells, splenic CD3+ and CD4+ cells were transferred from resistant mice to non-infected recipients prior to infection. Cytokine secretion, serum and faecal antibody titres and histological disease severity were assessed. Balb/c mice were resistant against re-infection. The course of infection was shorter in mice receiving primed spleen cells, CD3+ and CD4+ cells. Transfer of CD4+ T cells from resistant mice induced gamma-interferon, interleukin (IL)-2 and IL-17 secretion and suppressed IL-10 secretion. Anti-Citrobacter serum IgG1 and IgG2a enzyme-linked immunosorbent assay OD levels were increased. Faecal IgA secretion was increased while serum IgA was suppressed in recipients of CD4+ cells. Large bowel histology showed protection from colitis in recipients of primed cells as indicated by normal colonic epithelium. In Balb/c mice, C. rodentium infection is followed by resistance, which can be transferred by CD4+ cells. Transfer of protection is associated with IL-17 secretion, enhanced serum IgG and faecal IgA secretion. This is the first study to demonstrate the mechanisms by which systemic resistance from previously C. rodentium-infected mice can be transferred to non-infected animals.


Assuntos
Transferência Adotiva , Linfócitos T CD4-Positivos/transplante , Colite/prevenção & controle , Infecções por Enterobacteriaceae/prevenção & controle , Células Th1/imunologia , Animais , Anticorpos Antibacterianos/sangue , Linfócitos T CD4-Positivos/imunologia , Citrobacter rodentium/imunologia , Colite/imunologia , Colite/microbiologia , Infecções por Enterobacteriaceae/imunologia , Infecções por Enterobacteriaceae/patologia , Feminino , Citometria de Fluxo , Imunoglobulina A/análise , Imunoglobulina A/imunologia , Interferon gama/metabolismo , Interleucina-10/metabolismo , Interleucina-17/metabolismo , Interleucina-2/metabolismo , Camundongos , Camundongos Endogâmicos BALB C
13.
Int Arch Allergy Immunol ; 145(1): 24-32, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-17703097

RESUMO

BACKGROUND: Bacterial etiology of chronic rhinosinusitis (CRS) still remains controversial. Whereas Staphylococcus aureus enterotoxins have been detected in CRS, the impact of Staphylococcus epidermidis, a major commensal inhabitant of the nose, has not been studied. Among others, serine and cysteine proteases have been identified as factors of virulence in S. epidermidis. METHODS: S. epidermidis was examined in tissue biopsies of 30 CRS patients (16 with nasal polyposis) using standard procedures. Primary human nasal epithelial cells from inferior nasal turbinates (HNECs), from nasal polyps (NPECs) and A549 airway epithelial cells were stimulated with S. epidermidis supernatants DSM20044 or ATCC35984 and the IL-8 and GRO-alpha response was quantified by ELISA. Protease-triggered chemokine responses and involvement of NF-kappaB were investigated by addition of protease or NF-kappaB inhibitors. Activation of NF-kappaB was demonstrated by quantitative DNA binding assay. RESULTS: S. epidermidis was the most frequently isolated bacteria in the majority of CRS patients. HNECs and NPECs revealed no different IL-6 and IL-8 synthesis following stimulation with DSM20044 or ATCC35984. Stimulation of HNECs and A549 cells with S. epidermidis supernatants resulted in increased IL-8 and GRO-alpha expression which could be suppressed by the serine protease inhibitor AEBSF and the NF-kappaB inhibitor BAY 11 but not by the cysteine protease inhibitor E64. Results obtained for A549 cells were similar to HNECs. CONCLUSION: S. epidermidis was present in the majority of CRS specimens. Proinflammatory impact of S. epidermidis supernatants on nasal epithelial cells was demonstrated by serine protease-triggered and NF-kappaB-dependent chemokine responses.


Assuntos
Quimiocina CXCL1/imunologia , Interleucina-8/imunologia , Mucosa Nasal/imunologia , Rinite/microbiologia , Sinusite/microbiologia , Staphylococcus epidermidis/imunologia , Linhagem Celular , Células Cultivadas , Doença Crônica , Células Epiteliais/imunologia , Células Epiteliais/microbiologia , Humanos , Interleucina-6/imunologia , NF-kappa B/antagonistas & inibidores , Mucosa Nasal/citologia , Pólipos Nasais/imunologia , Pólipos Nasais/microbiologia , Nitrilas/farmacologia , Rinite/imunologia , Inibidores de Serina Proteinase/farmacologia , Sinusite/imunologia , Staphylococcus epidermidis/isolamento & purificação , Sulfonas/farmacologia
14.
Int J Artif Organs ; 30(9): 778-85, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17918122

RESUMO

Staphylococci have various strategies for resisting therapy that extend beyond classic mechanisms. Clinical experience with device-associated infections as well as with infections due to small-colony variants (SCVs) clearly shows that both antibacterial chemotherapy and host defense mechanisms are often unable to eliminate the pathogens and cure these infections. Of particular interest is the fact that in the past few years an increasing number of various foreign body-related infections due to staphylococcal SCVs have been reported. In this overview, the characteristics of SCVs recovered from clinical specimens and of defined mutants displaying the SCV phenotype are described. Their slow growth and changing biochemical and physiological features represent a challenge to clinical laboratory personnel, because recovery, identification, as well as susceptibility testing of these variants need particular efforts. In addition, the reduced susceptibility to aminoglycosides and the ability of SCVs to persist intracellularly require specific attention for the treatment of these infections. Thus, special efforts to search for these variants formed by Staphylococcus aureus or by coagulase-negative staphylococci should be considered when an infection is particularly resistant to therapy, persists for a long period or fails to respond to apparently adequate therapy with antimicrobial compounds.


Assuntos
Infecções Relacionadas à Prótese/microbiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus/classificação , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Modelos Animais de Doenças , Farmacorresistência Bacteriana , Corpos Estranhos , Regulação Bacteriana da Expressão Gênica , Genômica , Humanos , Mutação , Infecções Relacionadas à Prótese/diagnóstico , Infecções Relacionadas à Prótese/tratamento farmacológico , Infecções Estafilocócicas/diagnóstico , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/genética , Staphylococcus/efeitos dos fármacos , Staphylococcus/crescimento & desenvolvimento , Staphylococcus/patogenicidade , Virulência
15.
Int J Artif Organs ; 30(9): 792-7, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17918124

RESUMO

Staphylococcus aureus has emerged as a major cause of implant infections. It is known that it is able to produce several toxins that contribute to its armory of virulent weapons, but there are still no data on their prevalence among isolates recovered from biomaterial-centered infections. In this study, 200 Staphylococcus aureus isolates from infections related to different types of orthopedic implants (hip and knee arthroprostheses, internal and external fixation devices) were tested by polymerase chain reaction for the prevalence of genes encoding for leukotoxins. Although almost all isolates were positive for the ã-hemolysin gene (99%), none was positive for lukM. The leukotoxin genes lukE/lukD were found in 67% of isolates. The presence of lukE/lukD was significantly associated with that of Accessory Gene Regulatory locus agr II. The lukE/lukD-positive isolates were significantly more prevalent in the staphylococcal isolates from knee arthroprostheses than in the isolates from the other implant types. The genes encoding Panton-Valentine leukocidin components were detected in only one isolate that, curiously enough, was taken solely from a knee arthroprosthesis infection.


Assuntos
Proteínas de Bactérias/genética , Toxinas Bacterianas/genética , DNA Bacteriano/isolamento & purificação , Regulação Bacteriana da Expressão Gênica , Prótese Articular/efeitos adversos , Dispositivos de Fixação Ortopédica/efeitos adversos , Infecções Relacionadas à Prótese/microbiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/genética , Proteínas de Bactérias/isolamento & purificação , Toxinas Bacterianas/isolamento & purificação , Exotoxinas/genética , Fixadores Externos/efeitos adversos , Proteínas Hemolisinas/genética , Prótese de Quadril/efeitos adversos , Humanos , Fixadores Internos/efeitos adversos , Prótese do Joelho/efeitos adversos , Leucocidinas/genética , Reação em Cadeia da Polimerase , Staphylococcus aureus/química , Staphylococcus aureus/isolamento & purificação , Staphylococcus aureus/patogenicidade , Transativadores/genética
16.
Clin Exp Allergy ; 37(7): 1009-22, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17581194

RESUMO

BACKGROUND: The effects of protease-activated receptor-2 (PAR-2) stimulation on inflammation mechanisms of chronic rhinosinusitis (CRS) are still unknown. METHODS: PAR-2 receptor expression was investigated by immunohistochemistry and Taqman mRNA analysis in the mucosa of different rhinosinusitis entities. In primary nasal epithelial cell cultures, the function of PAR-2 and its ability to produce CXC, CC chemokines, and IL-6 were measured by calcium mobilization and stimulation tests. Inhibition tests were performed using cortisone, serine protease inhibitors, cysteine protease inhibitors, Pertussis toxin (PTX) and nuclear transcription factor (NF-kappaB) inhibition (BAY 11-7085). Signal transduction pathways were analysed by electromobility shift assays (EMSA) and NF-kappaB binding studies. RESULTS: The expression of PAR-2 was found to be increased in CRS specimens. The activation of PAR by trypsin or PAR-2-specific activating peptide (AP) caused an increase in cytosolic calcium, as well as the release of the CXC chemokines IL-8 and growth-related oncogene (GRO)-alpha, but not the release of CC chemokines or IL-6. AP-induced CXC chemokine was sensitive to PTX and activation of NF-kappaB was inhibited by BAY11-7085. Furthermore, a serine protease inhibitor significantly inhibited chemokine synthesis stimulated by trypsin and culture supernatants of staphylococci, whereas steroids and cysteine protease inhibitors had little effect. CONCLUSION: PAR-2 plays a role in serine protease-mediated regulation - staphylococcal and non-staphylococcal origin - of IL-8 and GRO-alpha in nasal epithelial cells, but not in the regulation of CC chemokines. PAR-2 may therefore be involved in the pathophysiology of CRS and NP at different sites of activation, namely (i) proteases, (ii) the PAR-2 receptor itself or (iii) the application of novel agents that block NF-kappaB/IkappaB-alpha signalling.


Assuntos
Quimiocinas CXC/biossíntese , Interleucina-8/biossíntese , NF-kappa B/metabolismo , Mucosa Nasal/metabolismo , Receptor PAR-2/metabolismo , Rinite/metabolismo , Serina Endopeptidases/metabolismo , Sinusite/metabolismo , Doença Aguda , Adulto , Idoso , Proteínas de Bactérias/metabolismo , Cálcio/metabolismo , Estudos de Casos e Controles , Células Cultivadas , Quimiocina CCL11 , Quimiocina CCL17 , Quimiocina CCL5/metabolismo , Quimiocina CXCL1 , Quimiocinas CC/metabolismo , Doença Crônica , Meios de Cultivo Condicionados/metabolismo , Feminino , Humanos , Interleucina-6/metabolismo , Masculino , Pessoa de Meia-Idade , NF-kappa B/antagonistas & inibidores , Mucosa Nasal/efeitos dos fármacos , Mucosa Nasal/imunologia , Mucosa Nasal/microbiologia , Pólipos Nasais/enzimologia , Pólipos Nasais/imunologia , Pólipos Nasais/metabolismo , Nitrilas/farmacologia , Peptídeos/farmacologia , Toxina Pertussis/farmacologia , RNA Mensageiro/metabolismo , Receptor PAR-2/agonistas , Receptor PAR-2/genética , Rinite/enzimologia , Rinite/imunologia , Rinite/microbiologia , Inibidores de Serina Proteinase/farmacologia , Transdução de Sinais , Sinusite/enzimologia , Sinusite/imunologia , Sinusite/microbiologia , Staphylococcus aureus/enzimologia , Sulfonas/farmacologia , Tripsina/metabolismo
17.
Clin Exp Immunol ; 144(3): 534-42, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16734624

RESUMO

While various microorganisms have been recovered from patients with chronic rhinosinusitis, the inflammatory impact of virulence factors, in particular proteases from Staphylococcus aureus and coagulase negative staphylococci on the nasal epithelium, has not yet been investigated. Expression of CXC chemokines was determined in the epithelium of patients with chronic rhinosinusitis by immunohistochemistry. In a cell culture system of A549 respiratory epithelial cells, chemokine levels were quantified by enzyme-linked immunosorbent assay (ELISA) after stimulation with supernatants originating from three different staphylococcal strains or with trypsin, representing a serine protease. Inhibition experiments were performed with prednisolone, with the serine protease inhibitor 4-(2-aminoethyl)-benzenesulphonylfluoride (AEBSF) and with the nuclear transcription factor (NF)-kappaBeta inhibitor (2E)-3-[[4-(1,1-dimethylethyl)phenyl]sulphonyl]-2-propenenitrite (BAY) 11-7085. Electromobility shift assays (EMSA) were used to demonstrate NF-kappaB-dependent protein synthesis. CXC chemokines interleukin (IL)-8, growth-related oncogene alpha (GRO-alpha) and granulocyte chemotactic protein-2 (GCP-2) were expressed in the patients' epithelium whereas epithelial cell-derived neutrophil attractant 78 (ENA-78) was rarely detected. In A549 cells, chemokines IL-8, ENA-78 and GRO-alpha but not GCP-2 were induced by trypsin and almost equal levels were induced by staphylococcal supernatants. IL-8, GRO-alpha and ENA-78 synthesis was suppressed almost completely by AEBSF and BAY 11-7085, whereas prednisolone reduced chemokine levels differentially dependent on the supernatant added. CXC chemokines were detectable in the epithelium of patients with chronic rhinosinusitis. Staphylococcal serine proteases induced CXC chemokines in A549 cells, probably by the activation of proteases activated receptors, and thus might potentially be involved in neutrophilic inflammation in chronic sinusitis.


Assuntos
Quimiocinas CXC/metabolismo , Mucosa Nasal/imunologia , Infiltração de Neutrófilos/imunologia , Rinite/imunologia , Sinusite/imunologia , Adulto , Idoso , Linhagem Celular , Quimiocina CXCL1 , Quimiocina CXCL5 , Doença Crônica , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/imunologia , Feminino , Humanos , Imunidade nas Mucosas , Técnicas Imunoenzimáticas , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Interleucina-8/metabolismo , Masculino , Metaloendopeptidases/imunologia , Pessoa de Meia-Idade , NF-kappa B/antagonistas & inibidores , NF-kappa B/fisiologia , Mucosa Nasal/efeitos dos fármacos , Nitrilas/farmacologia , Prednisolona/farmacologia , Inibidores de Serina Proteinase/farmacologia , Transdução de Sinais/imunologia , Sulfonas/farmacologia , Tripsina/imunologia
18.
Int J Artif Organs ; 29(4): 360-7, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16705604

RESUMO

The vast use of prosthetic materials in medicine over the last decades has been accompanied by the appearance of new opportunistic pathogens previously considered incapable of causing infections with significant morbidity and/or mortality. In this regard, the genus Staphylococcus enlisting numerous species usually characterized by a saprophytic habit covers a special role. Apart from Staphylococcus aureus and Staphylococcus epidermidis, well known for their large prevalence in implant-related infections, a number of further staphylococcal species are progressively being indicated for their pathogenic potential. The increasing attention on these opportunistic bacteria is due to an ever growing number of clinical reports, which is also deriving from a more accurate identification of these species with currently available techniques. This synopsis intends to offer an overview on recently emerging coagulase-negative staphylococci (CoNS) as well as coagulase-positive/-variable staphylococci exhibiting distinct traits of virulence, pathogenicity, and epidemiologic impact depending among others on the medical field, the type of prosthetic device and its anatomic location.


Assuntos
Doenças Transmissíveis Emergentes/microbiologia , Infecções Relacionadas à Prótese/microbiologia , Infecções Estafilocócicas/epidemiologia , Humanos , Virulência
19.
Int J Artif Organs ; 28(11): 1146-56, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16353121

RESUMO

The application of medical devices either for temporary or permanent use has become an indispensible part of almost all fields of medicine. However, foreign bodies are associated with a substantial risk of bacterial and fungal infections. Implant-associated infections significantly contribute to the still increasing problem of nosocomial infections. To reduce the incidence of such infections, specific guidelines providing evidence-based recommendations and comprising both technological and nontechnological strategies for prevention have been established. Strict adherence to hygienic rules during insertion or implantation of the device are aspects of particular importance. Besides such basic and indispensable aspects, the development of new materials which could withstand microbial adherence and colonization has become a major topic in recent years. Modification of surface by primarily physico-chemical methods may lead to a change in specific and unspecific interactions with microorganisms and, thus, to a reduction in microbial adherence. Medical devices made out of a material that would be ideally antiadhesive or at least colonization-resistant would be the most suitable candidates to avoid colonization and subsequent infection. However, it appears impossible to create a surface with an absolute 'zero'-adherence due to thermodynamical reasons and due to the fact that a modified material surface is in vivo rapidly covered by plasma and connective tissue proteins. Therefore, another concept for the prevention of implant-associated infections involves the impregnation of devices with various antimicrobial substances such as antibiotics, antiseptics, and/or metals. In fact, already commercially available materials for clinical use such as antimicrobial catheters have been introduced, in part with considerable impact on subsequent infections. However, future studies are warranted to translate the knowledge on the pathogenesis of device-associated infections into applicable prevention strategies.


Assuntos
Materiais Revestidos Biocompatíveis , Controle de Infecções/normas , Infecções Relacionadas à Prótese/prevenção & controle , Antibacterianos/administração & dosagem , Aderência Bacteriana , Contaminação de Equipamentos/prevenção & controle , Humanos , Guias de Prática Clínica como Assunto , Desenho de Prótese
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