RESUMO
La resistencia de antibióticos puede llegar a causar una amplia morbilidad y complicaciones. Objetivo: Determinar el perfil de resistencia antimicrobiana de Escherichia Coli y de Staphylococcus Saprophyticus, en pacientes con infección urinaria hospitalizados en el servicio de Medicina Interna del Hospital Municipal Los Olivos. Métodos: Estudio descriptivo, retrospectivo de corte transversal. Se realizó en el servicio de Medicina Interna del Hospital Municipal los Olivos (HMLO). Participantes: historia clínica de pacientes hospitalizados con infección urinaria en el servicio de Medicina Interna. Intervenciones: Según los criterios de inclusión y exclusión se obtuvieron, 96 historias clínicas (HC) del año 2013. Se utilizó un instrumento de recolección validado. Se realizó el análisis descriptivo con software estadístico STATA versión 25. Resultados: De las 96 HC, la edad promedio fue 55,04 años, los agentes microbianos más frecuentes fueron: la Escherichia coli con 85,3%, Staphylococcus saprophyticus 4.2% y Klebsiella pneumoniae 3,1%. La prevalencia de productores de betalactamasa espectro extendido (BLEE) fue 10,4%. Los antibióticos más resistentes fueron: trimetoprim/sulfametoxazol 89,6%, ampicilina 86%, piperacilina 84,6%, tetraciclina 79,2% y ciprofloxacino 70,8%. Los antibióticos más sensibles fueron: amikacina 100%, imipenem 100%, ertapenem 98%, meropenem 96% y piperacilina/tazobactam 96%. Conclusión: El uropatógeno más frecuente en pacientes con ITU hospitalizados fue la E. coli. Los antibióticos que presentaron resistencia a la E. coli fueron: trimetoprim/sulfametoxazol, ampicilina, piperacilina, tetraciclina y ciprofloxacino, y para el S. Saprophyticus fueron: amoxicilina/ ácido clavulánico, trimetoprim/sulfametoxazol, ceftriaxona y ciprofloxacino(AU)
Resistance to antibiotics may actually cause extensive morbidity and complications. Objective: To determine the antimicrobial resistance profile of Escherichia coli and Staphylococcus saprophyticus, in patients with urinary infection hospitalized in the Internal Medicine service of the Los Olivos Municipal Hospital. Methods: Descriptive, retrospective cross-sectional study. It was carried out in the Internal Medicine service of the Los Olivos Municipal Hospital (HMLO). Participants: clinical history of hospitalized patients with urinary infection in the Internal Medicine service. Interventions: According to the inclusion and exclusion criteria, 96 clinical records (HC) from 2013 were obtained. A validated collection instrument was used. Descriptive analysis was performed with STATA version 25 statistical software. Results: Of the 96 CHs, the average age was 55.04 years, the most frequent microbial agents were: Escherichia Coli with 85.3%, Staphylococcus saprophyticus 4.2% and Klebsiella pneumoniae 3.1%. The prevalence of extended spectrum beta-lactamase producers (ESBL) was 10.4%. The most resistant antibiotics were trimethoprim / sulfamethoxazole 89.6 %, ampicillin 86 %, piperacillin 84.6 %, tetracycline 79.2 % and ciprofloxacin 70.8 %. The most sensitive antibiotics were: amikacin 100%, imipenem 100%, ertapenem 98%, meropenem 96% and piperacillin / tazobactam 96%. Conclusion: The most common uropathogen in hospitalized UTI patients was E. coli. The antibiotics that showed resistance to E. coli were: trimethoprim/sulfamethoxazole, ampicillin, piperacillin, tetracycline, and ciprofloxacin, and for S. saprophyticus they were: amoxicillin/clavulanic acid, trimethoprim / sulfamethoxazole, ceftriaxone and ciprofloxacin(AU)
Assuntos
Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Infecções Urinárias/tratamento farmacológico , Farmacorresistência Bacteriana , Escherichia coli/efeitos dos fármacos , Staphylococcus saprophyticus/efeitos dos fármacos , Peru/epidemiologia , Resistência Microbiana a Medicamentos/imunologia , Prontuários Médicos , Estudos Transversais , Hospitais Públicos , Klebsiella pneumoniae/efeitos dos fármacos , Anti-Infecciosos Urinários/uso terapêuticoRESUMO
Recent studies on prevalence of urinary tract infection indicate that approximately one third population of the world has been suffering from this disease. The current study was designed to evaluate the antibacterial activity of aqueous-ethanolic extracts (30/70) of Tribulus terrestris (TT), Vaccinium macrocarpon (VM), Cuminum cyminum (CC), Rheum emodi (RE), Piper cubeba (PC) and their compound formulation "Crano-cure" against Escherichia coli, Klebsiella pneumonia, Staphylococcus saprophyticus and Proteus mirabilis through disc diffusion method and agar well methods compared with standard Ciprofloxacin. DPPH radical scavenging methods were applied for antioxidant activities and phytochemical analysis was also performed to detect the phytoconstituents. All the plants exhibited potent antibacterial strength while Crano-cure showed most potent results comparable with that of standard drug. The zone of inhibition produced by disk diffusion test was 26±0.34, 26±0.75, 26±0.00, 18±0.64, 22.5±0.52, 29±0.39, 32±0.00 mm and for agar well diffusion test 23±0.67, 22±0.46, 23±0.77, 20±0.00, 22±0.46, 24±0.52, 33±0.00 mm against Tribulus terrestris, Cuminum cyminum, Rheum emodi, Piper cubeba, Vaccinium macrocarpon, crano-cure and ciprofloxacin. Similarly, percentage inhibition for antioxidant potential was 78.74, 24.57, 58.75, 20.23, 88.88, 90.12 and 92.35 respectively. The tested plants exhibited remarkable antibacterial and antioxidant activities.
Assuntos
Antibacterianos/farmacologia , Antioxidantes/farmacologia , Cuminum , Piper , Extratos Vegetais/farmacologia , Rheum , Tribulus , Vaccinium macrocarpon , Compostos de Bifenilo , Ciprofloxacina/farmacologia , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Escherichia coli/efeitos dos fármacos , Indicadores e Reagentes , Klebsiella pneumoniae/efeitos dos fármacos , Picratos , Extratos Vegetais/química , Plantas Medicinais , Proteus mirabilis/efeitos dos fármacos , Staphylococcus saprophyticus/efeitos dos fármacos , Infecções UrináriasRESUMO
The ability to form biofilms on surfaces makes Staphylococcus saprophyticus (S. saprophyticus) becomes the main pathogenic factor in nosocomial infections. Previously, we demonstrated that baicalin (Bac) inhibited azithromycin-resistant S. saprophyticus (ARSS) biofilm formation. This investigation aims to explore the influence of baicalin on primary adhesion and aggregation phases of biofilm formation, and the treatment effect of baicalin and azithromycin on ARSS biofilm-associated infection. Crystal violet (CV) staining and scanning electron microscope (SEM) observations clearly showed that sub-inhibitory concentration baicalin inhibited ARSS biofilm formation when baicalin was added before the adhesion and aggregation phases. Baicalin significantly increased the relative adhesion inhibition rate and decreased the rate of bacteria aggregation in a dose-dependent manner. Moreover, CLSM and cell lysis assays revealed that baicalin inhibited the production of surface proteins and cell autolysis in bacteria adhesion and aggregation phases of biofilm formation. Meanwhile, the relative expressions of adhesion-related and autolysis-related genes were down-regulated by baicalin. In vivo, the combination of baicalin and azithromycin succeeded in eradicating ARSS from the mouse cutaneous infection model and decreasing the pathological injuries, the expressions of cytokines in infected tissue, and the number of inflammatory cells in the blood. Simultaneously, baicalin decreased the bacterial burdens in tubes, the level of TNF-α, and the number of monocytes and neutrophils compared with that of the SS and azithromycin groups. Based on these results, baicalin inhibited the adhesion and aggregation phases of biofilm formation by influenced the production of surface proteins and cell autolysis. Baicalin and azithromycin synergetically treated ARSS biofilm-associated infection.
Assuntos
Azitromicina , Aderência Bacteriana , Flavonoides , Staphylococcus saprophyticus , Animais , Aderência Bacteriana/efeitos dos fármacos , Biofilmes , Flavonoides/farmacologia , Proteínas de Membrana/metabolismo , Camundongos , Staphylococcus saprophyticus/efeitos dos fármacosRESUMO
Staphylococcus saprophyticus, the food-borne bacteria present in dairy products, ready-to-eat food and environmental sources, has been reported with antibiotic resistance, raising concerns about food microbial safety. The antimicrobial resistance of S. saprophyticus requires the development of new strategies. Light- and photosensitizer-based antimicrobial photodynamic inactivation (PDI) is a promising approach to control microbial contamination, whereas there is limited information regarding the effectiveness of PDI on S. saprophyticus biofilm control. In this study, PDI mediated by natural bioactive compound (curcumin) associated with LED was evaluated for its potential to prevent and disrupt S. saprophyticus biofilms. Biofilms were treated with curcumin (50, 100, 200 µM) and LED fluence (4.32 J/cm2, 8.64 J/cm2, 17.28 J/cm2). Control groups included samples treated only with curcumin or light, and samples received neither curcumin nor light. The action was examined on biofilm mass, viability, cellular metabolic activity and cytoplasmic membrane integrity. PDI using curcumin associated with LED exhibited significant antibiofilm activities, inducing biofilm prevention and removal, metabolic inactivation, intracellular membrane damage and cell death. Likewise, scanning electronic microscopy observations demonstrated obvious structural injury and morphological alteration of S. saprophyticus biofilm after PDI application. In conclusion, curcumin is an effective photosensitizer for the photodynamic control of S. saprophyticus biofilm.
Assuntos
Biofilmes/crescimento & desenvolvimento , Produtos Biológicos/farmacologia , Fotoquimioterapia , Staphylococcus saprophyticus/fisiologia , Biofilmes/efeitos dos fármacos , Contagem de Colônia Microbiana , Curcumina/farmacologia , Staphylococcus saprophyticus/citologia , Staphylococcus saprophyticus/efeitos dos fármacos , Staphylococcus saprophyticus/ultraestruturaRESUMO
Bacterial adhesion and the succeeding biofilm formation onto surfaces are responsible for implant- and device-associated infections. Bifunctional coatings integrating both nonfouling components and antimicrobial peptides (AMPs) are a promising approach to develop potent antibiofilm coatings. However, the current approaches and chemistry for such coatings are time-consuming and dependent on substrates and involve a multistep process. Also, the information is limited on the influence of the coating structure or its components on the antibiofilm activity of such AMP-based coatings. Here, we report a new strategy to rapidly assemble a stable, potent, and substrate-independent AMP-based antibiofilm coating in a nonfouling background. The coating structure allowed for the screening of AMPs in a relevant nonfouling background to identify optimal peptide combinations that work in cooperation to generate potent antibiofilm activity. The structure of the coating was changed by altering the organization of the hydrophilic polymer chains within the coatings. The coatings were thoroughly characterized using various surface analytical techniques and correlated with the efficiency to prevent biofilm formation against diverse bacteria. The coating method that allowed the conjugation of AMPs without altering the steric protection ability of hydrophilic polymer structure results in a bifunctional surface coating with excellent antibiofilm activity. In contrast, the conjugation of AMPs directly to the hydrophilic polymer chains resulted in a surface with poor antibiofilm activity and increased adhesion of bacteria. Using this coating approach, we further established a new screening method and identified a set of potent surface-tethered AMPs with high activity. The success of this new peptide screening and coating method is demonstrated using a clinically relevant mouse infection model to prevent catheter-associated urinary tract infection (CAUTI).
Assuntos
Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Incrustação Biológica/prevenção & controle , Materiais Revestidos Biocompatíveis/farmacologia , Proteínas Imobilizadas/farmacologia , Acrilamidas/química , Animais , Antibacterianos/síntese química , Peptídeos Catiônicos Antimicrobianos/síntese química , Catéteres/microbiologia , Materiais Revestidos Biocompatíveis/síntese química , Humanos , Proteínas Imobilizadas/síntese química , Indóis/química , Masculino , Camundongos Endogâmicos BALB C , Polímeros/química , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/fisiologia , Staphylococcus saprophyticus/efeitos dos fármacos , Staphylococcus saprophyticus/fisiologia , Infecções Urinárias/prevenção & controleRESUMO
A patient with a history of UTI acquired an isolate of Staphylococcus saprophyticus that was resistant to clindamycin, streptogramin A, pleuromutilins (LSPs), and oxacillin. A plasmid-located vga variant was identified in this pathogen, and the encoded protein showed a 39% to 67% identity to other previously characterized vga.
Assuntos
Proteínas de Bactérias/genética , Infecções Comunitárias Adquiridas/microbiologia , Farmacorresistência Bacteriana Múltipla/genética , Infecções Estafilocócicas/microbiologia , Staphylococcus saprophyticus/genética , Infecções Urinárias/microbiologia , Adolescente , Antibacterianos/farmacologia , Proteínas de Bactérias/classificação , DNA Bacteriano/genética , Feminino , Humanos , Testes de Sensibilidade Microbiana , Filogenia , Plasmídeos , Infecções Estafilocócicas/diagnóstico , Staphylococcus saprophyticus/efeitos dos fármacosRESUMO
This study aimed to investigate the structural and antimicrobial properties of Maillard reaction products (MRPs) in chicken liver protein (CLP) and its hydrolysate (CLPH) after sonication (SCLPH). The MRPs of CLP (CLPM), CLPH (CLPHM) and SCLPH (SCLPHM) were analyzed by several spectrometric techniques. The molecular weights of the CLPHM and SCLPHM were primarily between 1.35 kDa and 17 kDa. Moreover, the molecular weights in the CLPHM and SCLPHM below 1.35 kDa were increased, which indicated that cross-linking and thermal degradation occurred during the Maillard reaction (MR). The SCLPHM showed an obvious network skeleton, and the surface had many small crystal-shaped particles after ultrasound treatment and MR by scanning electron microscopy. The SCLPHM had more negative charges than the CLPHM, thus effectively inhibiting the growth of S. saprophyticus and E. coli. MR and ultrasound treatment could be a promising technology to expand the application prospects of low-value meat byproducts.
Assuntos
Antibacterianos/química , Fígado/metabolismo , Hidrolisados de Proteína/química , Animais , Antibacterianos/farmacologia , Galinhas , Escherichia coli/efeitos dos fármacos , Reação de Maillard , Peso Molecular , Hidrolisados de Proteína/farmacologia , Sonicação , Staphylococcus saprophyticus/efeitos dos fármacos , Temperatura de TransiçãoRESUMO
Chronic wounds and their associated bacterial infections are major issues in modern health care systems. Therefore, antimicrobial resistance (AMR), treatment costs, and number of disability-adjusted life-years have gained more interest. Recently, photodynamic therapy emerged as an effective approach against resistant and naïve bacterial strains with a low probability of creating AMR. In this study, needleless electrospinning was used to produce an indocyanine green (ICG) loaded poly(d,l-lactide) nanofibrous mesh as a photoresponsive wound dressing. The non-woven mesh had a homogeneous nanofibrous structure and showed long-term hydrolytic stability at different pH values. The antimicrobial activity was tested against several bacterial strains, namely Staphylococcus saprophyticus subsp. bovis, Escherichia coli DH5 alpha, and Staphylococcus aureus subsp. aureus. Upon irradiation with a laser of a specific wavelength (λ = 810 nm), the bacterial viability was significantly reduced by 99.978% (3.66 log10), 99.699% (2.52 log10), and 99.977% (3.64 log10), respectively. The nanofibrous mesh showed good biocompatibility, which was confirmed by the proliferation of mouse fibroblasts (L929) on the surface and into deeper parts of the mesh. Furthermore, a favorable proangiogenic effect was observed in ovo using the chorioallantoic membrane assay. In general, it can be concluded that ICG loaded nanofibers as an innovative wound dressing represent a promising strategy against chronic wounds associated with skin infections.
Assuntos
Materiais Biocompatíveis/farmacologia , Verde de Indocianina/farmacologia , Viabilidade Microbiana/efeitos dos fármacos , Poliésteres/química , Animais , Bandagens , Materiais Biocompatíveis/química , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Membrana Corioalantoide/irrigação sanguínea , Membrana Corioalantoide/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Verde de Indocianina/química , Camundongos , Nanofibras , Fotoquimioterapia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Staphylococcus saprophyticus/efeitos dos fármacos , Staphylococcus saprophyticus/crescimento & desenvolvimentoRESUMO
TAT (48-60) is a tridecapeptide from the envelope protein of HIV that was previously shown to possess cell-penetrating properties and antibacterial activity, making it a potential drug delivery agent for anticancer drugs and as antibacterial compound. Previous reports indicated that dimerization enhances the desired bioactivity of TAT; hence, we sought to synthesize multimeric TAT peptides. Herein, we describe the effects of multimerization on the antibacterial activity and secondary structure of the peptide. Terminal modifications such as N-acetylation and C-amidation were employed in the design. TATp monomer, dimer, and tetramer were synthesized using solid-phase peptide synthesis, purified by reversed-phase HPLC, and then characterized by mass spectrometry. Multimerization of the peptide did not change the secondary structure conformation. The CD analysis revealed a polyproline-II conformation for all peptide designs. Thus, this study provides a method of increasing the biological activity of the peptide by multimerization while retaining the secondary conformation of its monomeric unit. Furthermore, the bacteria Staphylococcus saprophyticus was found to be susceptible to the dimer and tetramer, with MIC50 of 12.50 µm and <1.56 µm, respectively. This suggests a structure-activity relationship whereby the antibacterial activity increases with increase in valency.
Assuntos
Antibacterianos/farmacologia , Staphylococcus saprophyticus/efeitos dos fármacos , Produtos do Gene tat do Vírus da Imunodeficiência Humana/farmacologia , Sequência de Aminoácidos , Antibacterianos/química , Cromatografia Líquida de Alta Pressão , Humanos , Testes de Sensibilidade Microbiana , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Staphylococcus saprophyticus/crescimento & desenvolvimento , Relação Estrutura-Atividade , Produtos do Gene tat do Vírus da Imunodeficiência Humana/químicaRESUMO
Staphylococcus saprophyticus is a uropathogenic bacteria responsible for acute urinary tract infections (UTIs) mainly in young female patients. Patients suffering from urinary catheterization, pregnant patients, the elderly as well as those with nosocomial UTIs are at greater risk of the colonizing S. saprophyticus infection. The causative factors include benign prostatic hyperplasia, indwelling catheter, neurogenic bladder, pregnancy, and history of frequent UTIs. Recent findings have exhibited that S. saprophyticus is resistant to several antimicrobial agents. Moreover, there is a global concern regarding the increasing level of antimicrobial resistance, which leads to treatment failure and reduced effectiveness of broad-spectrum antimicrobials. Therefore, a novel approach is being utilized to combat resistant microbes since the past few years. Subtractive proteome analysis has been performed with the entire proteome of S. saprophyticus strain American Type Culture Collection (ATCC) 15305 using several bioinformatics servers and software. The proteins that were non-homologous to humans and bacteria were identified for metabolic pathway analysis. Only four cytoplasmic proteins were found possessing the potential of novel drug target candidates. The development of innovative therapeutic agents by targeting the inhibition of any essential proteins may disrupt the metabolic pathways specific to the pathogen, thus causing destruction as well as eradication of the pathogen from a particular host. The identified targets can facilitate in designing novel and potent drugs against S. saprophyticus strain ATCC 15305.
Assuntos
Proteômica , Infecções Estafilocócicas , Staphylococcus saprophyticus , Infecções Urinárias , Idoso , Biologia Computacional , Feminino , Humanos , Redes e Vias Metabólicas , Gravidez , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus saprophyticus/efeitos dos fármacos , Staphylococcus saprophyticus/genéticaRESUMO
Tachylectin-2, a 27-kDa protein consisting of a five-bladed ß-propeller structure, is purified by three steps of chromatography, including dextran sulfate-Sepharose CL-6B, CM-Sepharose CL-6B, and Mono S. Three isolectins of tachylectin-2 including tachylectin-2a, -2b, and -2c are purified. These isolectins exhibit hemagglutinating activity against human A-type erythrocytes in a Ca2+-independent manner with tachylectin-2b showing the highest activity. Tachylectin-2b specifically agglutinates Staphylococcus saprophyticus KD. The tachylectin-2b-mediated hemagglutination is inhibited in the presence of GlcNAc and GalNAc. The association constants for GlcNAc and GalNAc are Ka = 1.95 × 104 M-1 and Ka = 1.11 × 103 M-1, respectively. Ultracentrifugation analysis shows that tachylectin-2b is present in monomer form in solution.
Assuntos
Caranguejos Ferradura/metabolismo , Lectinas/isolamento & purificação , Lectinas/farmacologia , Acetilgalactosamina/farmacologia , Acetilglucosamina/farmacologia , Testes de Aglutinação , Animais , Cálcio/metabolismo , Cromatografia , Eritrócitos/efeitos dos fármacos , Hemaglutinação/efeitos dos fármacos , Caranguejos Ferradura/química , Humanos , Lectinas/química , Isoformas de Proteínas/química , Isoformas de Proteínas/isolamento & purificação , Isoformas de Proteínas/farmacologia , Multimerização Proteica , Staphylococcus saprophyticus/efeitos dos fármacosRESUMO
AIMS: Urease is a virulence factor for the urinary tract pathogens Staphylococcus saprophyticus and Proteus mirabilis. Dimethylsulfoxide (DMSO) is structurally similar to urea, used as a solvent for urease inhibitors, and an effective treatment for interstitial cystitis/bladder pain syndrome (IC/BPS). The aims of this study were to test DMSO as a urease inhibitor and determine its physiological effects on S. saprophyticus and P. mirabilis. METHODS AND RESULTS: Urease activity in extracts and whole cells was measured by the formation of ammonium ions. Urease was highly sensitive to noncompetitive inhibition by DMSO (Ki about 6 mmol l-1 ). DMSO inhibited urease activity in whole cells, limited bacterial growth in media containing urea, and slowed the increase in pH which occurred in artificial urine medium. CONCLUSIONS: DMSO should be used with caution as a solvent when testing plant extracts or other potential urease inhibitors. Because it can inhibit bacterial growth and delay an increase in pH, it may be an effective treatment for urinary tract infections. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first detailed study of the inhibition of urease by DMSO. Dimethylsulfoxide may be used to treat urinary tract infections that are resistant to antibiotics or herbal remedies.
Assuntos
Dimetil Sulfóxido/farmacologia , Inibidores Enzimáticos/farmacologia , Proteus mirabilis/efeitos dos fármacos , Staphylococcus saprophyticus/efeitos dos fármacos , Urease/antagonistas & inibidores , Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Proteus mirabilis/crescimento & desenvolvimento , Proteus mirabilis/metabolismo , Proteus mirabilis/patogenicidade , Staphylococcus saprophyticus/crescimento & desenvolvimento , Staphylococcus saprophyticus/metabolismo , Staphylococcus saprophyticus/patogenicidade , Ureia/metabolismo , Urease/metabolismo , Infecções Urinárias/microbiologia , Fatores de Virulência/antagonistas & inibidores , Fatores de Virulência/metabolismoRESUMO
The naturally occurring anthraquinone derivative hypericin is a highly potent photosensitiser. Several in vitro studies show high phototoxicity of the pigment towards gram-positive bacteria. Nevertheless, the highly lipophilic nature and poor bioavailability prevent its application in daily clinical practice thus leading to a limited therapeutic value of hypericin. Liposomal encapsulation could help overcome these limitations and would make hypericin available for daily clinical practice. The use of liposomes as carriers for hypericin in antimicrobial photodynamic therapy (aPDT) is quite new. The aim of this work was to improve the photodynamic efficiency of the previously mentioned carriers by entrapping hypericin in the aqueous compartment of the liposomes. Therefore, a water-soluble inclusion complex of hypericin and (2-hydroxypropyl)-beta-cyclodextrin (Hyp-HPßCD) was prepared. After encapsulation of the inclusion complex into DSPC and DSPC/DPPC/DSPE-PEG liposomes with the dehydration-rehydration vesicle (DRV) method, the formulations were physicochemical characterised. The photodynamic efficiency towards the gram-positive model strain Staphylococcus saprophyticus subsp. bovis. was tested on planktonic cells as well as on biofilms. DSPC liposomes achieved a 4.1log reduction and the DSPC/DPPC/DSPE-PEG liposomes a 2.6log reduction in growth of planktonic bacteria, while Hyp-HPßCD showed total eradication. Even bacterial cells growing in a biofilm could be treated effectively in vitro.
Assuntos
Antibacterianos/química , Lipossomos/química , Perileno/análogos & derivados , Antracenos , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Composição de Medicamentos/métodos , Perileno/química , Fosfatidiletanolaminas/química , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/química , Polietilenoglicóis/química , Staphylococcus saprophyticus/efeitos dos fármacos , beta-Ciclodextrinas/químicaRESUMO
Antimicrobial resistance is one of the most serious problems that researchers of multiple disciplines are working on. The number of new antibiotics and their targeted structures have continuously decreased emphasizing the demand of alternative therapy for bacterial infections. Photodynamic therapy is such a promising strategy that has been proven to be effective against a wide range of bacterial strains. In this study, an inhalable nanoformulation for photodynamic therapy against respiratory infections was developed in the form of nano-in-microparticles consisting of curcumin nanoparticles embedded in a mannitol matrix. The produced nano-in-microparticles exhibited suitable aerodynamic properties with a mass median aerodynamic diameter of 2.88⯱â¯0.13⯵m and a high fine particle fraction of 60.99⯱â¯9.50%. They could be readily redispersed in an aqueous medium producing the original nanoparticles without any substantial changes in their properties. This was confirmed using dynamic light scattering and electron microscopy. Furthermore, the redispersed nanoparticles showed an efficient antibacterial photoactivity causing 99.99992% (6.1log10) and 97.75% (1.6log10) reduction in the viability of Staphylococcus saprophyticus subsp. bovis and Escherichia coli DH5 alpha respectively. Based on these findings, it can be concluded that nano-in-microparticles represent promising drug delivery systems for antimicrobial photodynamic therapy.
Assuntos
Antibacterianos/química , Curcumina/química , Nanopartículas/química , Administração por Inalação , Antibacterianos/farmacologia , Química Farmacêutica/métodos , Composição de Medicamentos/métodos , Sistemas de Liberação de Medicamentos/métodos , Inaladores de Pó Seco/métodos , Escherichia coli/efeitos dos fármacos , Excipientes/química , Manitol/química , Tamanho da Partícula , Fotoquimioterapia/métodos , Pós/química , Staphylococcus saprophyticus/efeitos dos fármacosRESUMO
Introduction and Objective: Urinary catheters and stents are frequently prone to catheter-associated urinary tract infections (CAUTI) through biofilm formation. Several strategies have been evaluated in search of a stent coating to reliably prevent adherence of bacteria and biofilm. Previous in vivo and in vitro research with methoxylated polyethylene glycol 3,4-dihydroxyphenylalanine (DOPA) copolymer as a candidate coating showed promising results to reduce the bacterial attachment. We aimed to further enhance this antimicrobial activity by adding antimicrobial agents to newly synthesized DOPA-based copolymers. Materials and Methods: Building on our previous experience, novel copolymers were engineered based on DOPA. Quaternary ammonium groups and silver particles were added by cross-linking to increase the antimicrobial activity through both kill-by-contact and planktonic killing. After coating polyurethane sheets and measuring contact angles, all candidate coatings were challenged in vitro with an Escherichia coli culture. The most promising coatings were then further evaluated against a panel of seven clinically relevant uropathogens and planktonic killing, and microbial attachment was determined. Results: Initially, seven coatings were developed, referred to as Surphys 093-099. The most significant increase in contact angle was identified in Surphys-095 and -098. Surphys coatings S-094, S-095, and S-098 were cross-linked with silver and exhibited profound antimicrobial properties when challenged with E. coli. Further testing demonstrated S-095 to have antimicrobial efficacy against gram-positive and gram-negative bacteria at different silver-loading concentrations. The final coating, consisting of a 2 mg/mL solution of S-095 cross-linked with 0.25 mg/mL AgNO3, appeared to be highly bactericidal showing a ≥99.9% bacterial killing effect while remaining below cytotoxicity levels. Conclusions: We were able to engineer DOPA-based copolymers and add quaternary ammonium and silver particles, thus increasing the bactericidal properties of the coating. These coatings have exhibited a biologically significant ability to prevent uropathogens from attaching to biomaterials and represent a realistic opportunity to combat CAUTI.
Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Di-Hidroxifenilalanina/farmacologia , Dopaminérgicos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Poliuretanos , Infecções Urinárias/prevenção & controle , Anti-Infecciosos , Infecções Relacionadas a Cateter/prevenção & controle , Materiais Revestidos Biocompatíveis , Stents Farmacológicos , Enterococcus faecalis/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Humanos , Técnicas In Vitro , Klebsiella pneumoniae/efeitos dos fármacos , Teste de Materiais , Polímeros , Proteus mirabilis/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Nitrato de Prata/farmacologia , Staphylococcus epidermidis/efeitos dos fármacos , Staphylococcus saprophyticus/efeitos dos fármacos , Cateteres UrináriosRESUMO
Staphylococcus equorum is a benign bacterium and the predominant species in high-salt fermented food. Some strains of S. equorum contain antibiotic-resistance plasmids, such as pSELNU1 that contains a lincosamide nucleotidyltransferase (lnuA) gene and confers resistance to lincomycin. Previously, we showed that pSELNU1 is transferred to other bacteria under laboratory growth conditions. However, it is not known if the plasmid can be transferred to other bacteria during food fermentation (in situ) or during passage through animal intestines (in vivo). In this study, we examined the in situ and in vivo transfer of pSELNU1 using Staphylococcus saprophyticus as a recipient. During soybean fermentation, pSELNU1 was transferred to S. saprophyticus at a rate of 1.9 × 10-5-5.6 × 10-6 per recipient in the presence of lincomycin. However, during passage through murine intestines, the plasmid was transferred at similar rates (1.3 × 10-5 per recipient) in the absence of lincomycin, indicating that the plasmid transfer is much more efficient under in vivo conditions. Based on these results, we conclude that it is prudent to examine food fermentation starter candidates for the presence of mobile genetic elements containing antibiotic resistance genes and to select candidates lacking these genes.
Assuntos
Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos/genética , Glycine max/microbiologia , Intestinos/microbiologia , Lincomicina/farmacologia , Plasmídeos/genética , Staphylococcus saprophyticus/genética , Animais , Coagulase/análise , Feminino , Alimentos Fermentados/microbiologia , Técnicas de Transferência de Genes , Sequências Repetitivas Dispersas , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Glycine max/metabolismo , Staphylococcus saprophyticus/efeitos dos fármacosRESUMO
The complete nucleotide sequence of a tetracycline-resistance gene (tetK)-carrying plasmid from a Staphylococcus saprophyticus isolate from jeotgal, a Korean high-salt-fermented seafood, was determined. The plasmid, designated pSSTET1, was 4439 bp in length and encoded typical elements found in plasmids that replicate via a rolling-circle mechanism, including the replication protein gene (rep), a double-stranded origin of replication, a single-stranded origin of replication, and a counter-transcribed RNA sequence. Additionally, the plasmid recombination enzyme gene (pre), which may be involved in inter-plasmid recombination and conjugation, was found. Each gene exhibited >94% sequence identity with those harbored in other Staphylococcus species. pSSTET1 was conditionally transferred to Staphylococcus species in a host-dependent manner and transferred to an Enterococcus faecalis strain in vitro. Antibiotic susceptibility of the transconjugants was host-dependent and transconjugants maintained a tetracycline-resistant phenotype in the absence of selective pressure over 100 generations.
Assuntos
Alimentos Fermentados/microbiologia , Microbiologia de Alimentos , Alimentos Marinhos/microbiologia , Staphylococcus saprophyticus/efeitos dos fármacos , Staphylococcus saprophyticus/genética , Resistência a Tetraciclina/genética , Animais , Conjugação Genética , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/genética , Genes Bacterianos , Humanos , Plasmídeos , República da CoreiaRESUMO
The constant increase in multi-resistant bacterial strains and the decline in the number of newly approved antibiotics necessitate the development of alternative approaches to antibiotic treatment. In this study, a modern alternative approach to antibiotic therapy using photosensitiser encapsulated polymeric nanoparticles is presented. Cationic nanoparticles were prepared using a biodegradable and biocompatible polymer poly (lactic-co-glycolic acid), a stabiliser poly (vinyl alcohol) and chitosan. Dynamic light scattering and laser Doppler anemometry were used to determine particle size distribution and ζ-potential respectively. To quantify the antibacterial photodynamic effect of the nanoparticles, in vitro studies were performed using Staphylococcus saprophyticus subsp. bovis and Escherichia coli DH5 alpha to represent both a gram-positive as well as a gram-negative strain. It was demonstrated that the particle ζ-potential significantly influenced the antibacterial phototoxicity, gaining up to 3 log10 higher efficacy for chitosan coated nanoparticles. Furthermore, neither irradiation alone nor curcumin in absence of light led to a significant growth reduction, confirming the photodynamic effect of curcumin. Electron microscopy has been used to study the morphological characteristics of the nanoparticles as well as their interaction with bacteria and the changes of bacterial morphology and ultrastructure upon photodynamic treatment. An increased adherence of the chitosan modified nanoparticles to the bacteria and structural damage upon photodynamic treatment was clearly evident and confirmed the results from in vitro studies.
Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Curcumina/química , Curcumina/farmacologia , Nanopartículas/química , Escherichia coli/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Staphylococcus saprophyticus/efeitos dos fármacosRESUMO
The Japanese Surveillance Committee conducted a second nationwide surveillance of antimicrobial susceptibility patterns of uropathogens responsible for acute uncomplicated cystitis (AUC) in premenopausal patients aged 16-40 years old at 31 hospitals throughout Japan from March 2015 to February 2016. In this study, the susceptibility of causative bacteria (Escherichia coli, Klebsiella pneumoniae, Staphylococcus saprophyticus) for various antimicrobial agents was investigated by isolation and culturing of organisms obtained from urine samples. In total, 324 strains were isolated from 361 patients, including E. coli (n = 220, 67.9%), S. saprophyticus (n = 36, 11.1%), and K. pneumoniae (n = 7, 2.2%). The minimum inhibitory concentrations (MICs) of 20 antibacterial agents for these strains were determined according to the Clinical and Laboratory Standards Institute (CLSI) manual. At least 93% of the E. coli isolates showed susceptibility to fluoroquinolones and cephalosporins, whereas 100% of the S. saprophyticus isolates showed susceptibility to fluoroquinolones and aminoglycosides. The proportions of fluoroquinolone-resistant and extended-spectrum ß-lactamase (ESBL)-producing E. coli strains were 6.4% (13/220) and 4.1% (9/220), respectively. The antimicrobial susceptibility of K. pneumoniae was retained during the surveillance period, while no multidrug-resistant strains were identified. In summary, antimicrobial susceptibility results of our second nationwide surveillance did not differ significantly from those of the first surveillance. Especially the numbers of fluoroquinolone-resistant and ESBL-producing E. coli strains were not increased in premenopausal patients with AUC in Japan.
Assuntos
Antibacterianos/farmacologia , Cistite/tratamento farmacológico , Farmacorresistência Bacteriana Múltipla , Escherichia coli/efeitos dos fármacos , Klebsiella pneumoniae/efeitos dos fármacos , Staphylococcus saprophyticus/efeitos dos fármacos , Adolescente , Adulto , Antibacterianos/uso terapêutico , Cistite/epidemiologia , Cistite/microbiologia , Monitoramento Epidemiológico , Escherichia coli/isolamento & purificação , Escherichia coli/metabolismo , Feminino , Humanos , Japão , Klebsiella pneumoniae/isolamento & purificação , Klebsiella pneumoniae/metabolismo , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Staphylococcus saprophyticus/isolamento & purificação , Staphylococcus saprophyticus/metabolismo , Adulto Jovem , beta-Lactamases/metabolismoRESUMO
Antibiotic resistance is increasing among Staphylococcus saprophyticus strains isolated from urinary tract infection. This necessitates alternative therapies. For this, a lytic phage (vB_SsapS-104) against S. saprophyticus, which formed round and clear plaques on bacterial culture plates, was isolated from hospital wastewater and characterized. Microscopy analysis showed that it had a small head (about 50 nm), tail (about 80 nm), and a collar (about 22 nm in length and 19 nm in width) indicating to be a phage within Siphoviridae family. Phage vB_SsapS-104 showed a large latency period of about 40 min, rapid adsorption rate that was significantly enhanced by MgCl2 and CaCl2, and high stability to a wide range of temperatures and pH values. Restriction analyses demonstrated that phage consists of a double-stranded DNA with an approximate genome size of 40 Kb. BLAST results did not show high similarity (megablast) with other previously identified phages. But, in Blastn, similarity with Staphylococcus phages was observed. Phage vB_SsapS-104 represented high anti-bacterial activity against S. saprophyticus isolates in vitro as it was able to lyse 8 of the 9 clinical isolates (%88.8) obtained from a hospital in Gorgan, Iran. It was a S. saprophyticus-specific phage because no lytic activity was observed on some other pathogenic bacteria tested. Therefore, phage vB_SsapS-104 can be considered as a specific virulent phage against of S. saprophyitcus isolated from urinary tract infection. This study provided the partial genomic characterization of S. saprophyticus phage and its application against urinary tract infection associated with S. saprophyticus. This phage also can be considered as a good candidate for a therapeutic alternative in the future.