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1.
ACS Biomater Sci Eng ; 7(5): 1827-1835, 2021 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-33966376

RESUMO

The progressively increasing degree of multiple antibiotic resistance in Gram-negative bacteria challenges the treatment of severe bacterial infection-induced chronic skin wounds. To address this problem, we developed a straightforward strategy to prepare a composite film consisting of antibacterial nanoparticles (4,6-diamino-2-pyrimidinethiol-functionalized gold nanoparticles, DAPT-Au NPs) and a silk fibroin (SF) mixed-matrix membrane (DAPT-Au-SF MMM) as a wound dressing for treating multidrug-resistant (MDR) E. coli- induced infection. The good hydrophilicity of SF allows the highly effective release of DAPT-Au NPs from the composite film to combat pathogens within minutes. The antibacterial activity of the composite film is maintained regardless of antimicrobial susceptibility. DAPT-Au-SF MMMs also promote healing in rat wounds infected by clinically isolated MDR E. coli. Our findings provide a new strategy to extend the use of gold nanomaterials and SF-based wound dressings, especially against drug-resistant bacterial infections.


Assuntos
Antibacterianos/uso terapêutico , Infecções por Escherichia coli/tratamento farmacológico , Fibroínas , Nanopartículas Metálicas , Ferimentos e Lesões/tratamento farmacológico , Ferimentos e Lesões/microbiologia , Animais , Escherichia coli , Ouro , Ratos
2.
Int J Mol Sci ; 22(8)2021 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-33924416

RESUMO

Local administration of antiseptics is required to prevent and fight against biofilm-based infections of chronic wounds. One of the methods used for delivering antiseptics to infected wounds is the application of dressings chemisorbed with antimicrobials. Dressings made of bacterial cellulose (BC) display several features, making them suitable for such a purpose. This work aimed to compare the activity of commonly used antiseptic molecules: octenidine, polyhexanide, povidone-iodine, chlorhexidine, ethacridine lactate, and hypochlorous solutions and to evaluate their usefulness as active substances of BC dressings against 48 bacterial strains (8 species) and 6 yeast strains (1 species). A silver dressing was applied as a control material of proven antimicrobial activity. The methodology applied included the assessment of minimal inhibitory concentrations (MIC) and minimal biofilm eradication concentration (MBEC), the modified disc-diffusion method, and the modified antibiofilm dressing activity measurement (A.D.A.M.) method. While in 96-well plate-based methods (MIC and MBEC assessment), the highest antimicrobial activity was recorded for chlorhexidine, in the modified disc-diffusion method and in the modified A.D.A.M test, povidone-iodine performed the best. In an in vitro setting simulating chronic wound conditions, BC dressings chemisorbed with polyhexanide, octenidine, or povidone-iodine displayed a similar or even higher antibiofilm activity than the control dressing containing silver molecules. If translated into clinical conditions, the obtained results suggest high applicability of BC dressings chemisorbed with antiseptics to eradicate biofilm from chronic wounds.


Assuntos
Anti-Infecciosos Locais/farmacologia , Bactérias/isolamento & purificação , Bandagens/microbiologia , Biofilmes/crescimento & desenvolvimento , Celulose/farmacologia , Ferimentos e Lesões/microbiologia , Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Biofilmes/efeitos dos fármacos , Doença Crônica , Farmacorresistência Bacteriana/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Prata/farmacologia , Leveduras/efeitos dos fármacos
3.
Biosensors (Basel) ; 11(3)2021 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-33800856

RESUMO

The rapid detection of pathogens in infected wounds can significantly improve the clinical outcome. Wound exudate, which can be collected in a non-invasive way, offers an attractive sample material for the detection of pathogens at the point-of-care (POC). Here, we report the development of a nucleic acid lateral flow immunoassay for direct detection of isothermally amplified DNA combined with fast sample preparation. The streamlined protocol was evaluated using human wound exudate spiked with the opportunistic pathogen Pseudomonas aeruginosa that cause severe health issues upon wound colonization. A detection limit of 2.1 × 105 CFU per mL of wound fluid was achieved, and no cross-reaction with other pathogens was observed. Furthermore, we integrated an internal amplification control that excludes false negative results and, in combination with the flow control, ensures the validity of the test result. The paper-based approach with only three simple hands-on steps has a turn-around time of less than 30 min and covers the complete analytical process chain from sample to answer. This newly developed workflow for wound fluid diagnostics has tremendous potential for reliable pathogen POC testing and subsequent target-oriented therapy.


Assuntos
Técnicas Biossensoriais , Imunoensaio , Ácidos Nucleicos , Exsudatos e Transudatos/microbiologia , Humanos , Limite de Detecção , Técnicas de Amplificação de Ácido Nucleico , Sistemas Automatizados de Assistência Junto ao Leito , Ferimentos e Lesões/microbiologia
4.
Int J Nanomedicine ; 16: 223-235, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33469282

RESUMO

Purpose: Today, the development of wounds and their side effects has become a problematic issue in medical science research. Hydrogel-based dressings are some of the best candidates for this purpose due to their ability to keep the wound bed clean, as well as provide proper moisture, tissue compatibility and an antimicrobial effect for wound healing. On the other hand, copper and its compounds have been used experimentally for many years in studies as an antimicrobial substance. Various studies have been performed determining the antimicrobial properties of this element, during which significant effects on infection have been shown. Methods: Chitosan/polyvinyl alcohol/copper nanofibers were successfully prepared by incorporating Cu onto a polymer electrospun using an electrospinning technique. A double-layer nanofiber composed of poly(vinyl alcohol) and chitosan incorporated with Cu nanoparticles as a protective layer and a second layer composed of polyvinylpyrrolidone (PVP) nanofibers which was adjacent to the damaged cells was prepared. The prepared nanofiber was characterized by TGA, FT-IR, TEM, SEM-EDS, and X-ray powder diffraction. The antimicrobial efficiency of the nanofibers was demonstrated through biological tests on some Gram-positive and Gram-negative bacteria. Finally, the prepared hydrogel formulations were prepared to evaluate their effect on the healing process of rat open wounds. Results: In this study, data from SEM, TEM, EDS, and XRD confirmed the formation of uniform fibers with nanodiameters and the presence of Cu nanoparticles onto the electrospun nanofibers. The antibacterial activity of copper was observed against all of the selected bacteria, but the Gram-positive bacteria were more sensitive compared to Gram-negative bacteria. Conclusion: According to the obtained results, the hydrogel wound dressing prepared in this research can be effective in caring for open wounds in the early stages of wound healing and preventing the occurrence of prolonged open wounds.


Assuntos
Antibacterianos/farmacologia , Bandagens , Quitosana/química , Cobre/química , Álcool de Polivinil/química , Ferimentos e Lesões/microbiologia , Animais , Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Íons , Masculino , Testes de Sensibilidade Microbiana , Nanofibras/ultraestrutura , Ratos Wistar , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Cicatrização/efeitos dos fármacos , Difração de Raios X
5.
PLoS One ; 15(6): e0235093, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32584878

RESUMO

Bacterial biofilms are one of the major issues in the treatment of chronic infections such as chronic wounds, where biofilms are typically polymicrobial. The synergy between species can occur during most polymicrobial infections, where antimicrobial resistance enhances as a result. Furthermore, self-produced extracellular polymeric substance (EPS) in biofilms results in a high tolerance to antibiotics that complicates wound healing. Since most antibiotics fail to remove biofilms in chronic infections, new therapeutic modalities may be required. Disruption of EPS is one of the effective approaches for biofilm eradication. Therefore, degradation of EPS using enzymes may result in improved chronic wounds healing. In the current study, we investigated the efficacy of trypsin, ß-glucosidase, and DNase I enzymes on the degradation of dual-species biofilms of Pseudomonas aeruginosa and Staphylococcus aureus in a wound-like medium. These species are the two most common bacteria associated with biofilm formation in chronic wounds. Moreover, the reduction of minimum biofilm eradication concentration (MBEC) of meropenem and amikacin was evaluated when combined with enzymes. The minimum effective concentrations of trypsin, ß-glucosidase, and DNase I enzymes to degrade biofilms were 1 µg/ml, 8 U/ml, and 150 U/ml, respectively. Combination of 0.15 µg/ml trypsin and 50 U/ml DNase I had a significant effect on S. aureus-P. aeruginosa biofilms which resulted in the dispersal and dissolution of all biofilms. In the presence of the enzymatic mixture, MBECs of antibiotics showed a significant decrease (p < 0.05), at least 2.5 fold. We found that trypsin/DNase I mixture can be used as an anti-biofilm agent against dual-species biofilms of S. aureus-P. aeruginosa.


Assuntos
Antibacterianos/farmacologia , Biofilmes , Infecções por Pseudomonas/tratamento farmacológico , Pseudomonas aeruginosa/fisiologia , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/fisiologia , Infecção dos Ferimentos/tratamento farmacológico , Ferimentos e Lesões/microbiologia , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Quimioterapia Combinada , Humanos , Infecção dos Ferimentos/microbiologia
6.
Artigo em Inglês | MEDLINE | ID: mdl-32517246

RESUMO

The Beach Exposure and Child Health Study (BEACHES) quantified the behavior of children at recreational beach areas to evaluate how various behaviors might affect their exposure to environmental contaminants such as bacteria and chemicals. Due to limited information in the study about abrasions, we conducted a literature review to examine how marine bacteria cause infections in open wounds. The literature review revealed possible adverse health effects from the bacterium Vibrio vulnificus due to its increasing prevalence and the severity of infection. We used data from the BEACHES study to review children's behavior and their susceptibility to abrasions. Children six years of age and younger were evaluated before and after 1 hour of play for open or healing abrasions at two beaches in Miami-Dade County, Florida (Crandon and Haulover), and two beaches in Galveston County, Texas (Stewart and Seawall). The children were videotaped to monitor their activities and to determine the behavior that would increase their susceptibility to obtaining abrasions. Overall, 58.2% of the children had at least one existing abrasion before playing at the beach, while 8.2% of the children acquired a new abrasion during their time at the beach. Children who acquired new abrasions most often played in the sea water, with new abrasions most frequently occurring on exposed skin surfaces such as the knees. Proper wound care before and after visiting the beach should be encouraged to minimize the risk of bacterial infection, especially considering the possible detrimental impacts that can be caused by some bacterial pathogens through wound exposures.


Assuntos
Praias , Microbiologia da Água , Infecção dos Ferimentos , Ferimentos e Lesões/etiologia , Criança , Pré-Escolar , Monitoramento Ambiental , Florida , Humanos , Água do Mar , Texas , Ferimentos e Lesões/microbiologia
7.
Int J Syst Evol Microbiol ; 70(6): 3597-3605, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32501786

RESUMO

Strains of a Gram-negative, aerobic, rod-shaped, non-spore-forming bacterium, designated MY50T, MY63 and MY101, were isolated from wound samples of three hospitalized patients in Yangon, Myanmar. Strains MY50T, MY63 and MY101 grew at temperatures of 4-44 °C, in media containing 1.0-7.0 % (w/v) NaCl and at pH 6.0-9.5. Phylogenetic analysis based on 16S rRNA gene and whole genome sequences showed that these strains belonged to the genus Pseudomonas and were part of the Pseudomonas oleovorans group and located close to Pseudomonas guguanensis and Pseudomonas mendocina. Whole-genome comparisons, using average nucleotide identity and digital DNA-DNA hybridization analyses, confirmed that strains MY50T, MY63 and MY101 were the same strain and they were a distinct species in the P. oleovorans group. Results of phenotypic characterization tests demonstrated that utilization of p-hydroxy-phenylacetic acid, glycerol, l-pyroglutamic acid and quinic acid could distinguish these strains from other species of the P. oleovorans group. These genetic and phenotypic characteristics suggest that they should be classified as representing a novel species, under the proposed name Pseudomonas yangonensis sp. nov. The type strain is MY50T (=LMG 31602T,=JCM 33396T), with a DNA G+C content of 62.82 mol%.


Assuntos
Filogenia , Pseudomonas/classificação , Ferimentos e Lesões/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Genes Bacterianos , Hospitais , Humanos , Mianmar , Hibridização de Ácido Nucleico , Pseudomonas/isolamento & purificação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
8.
Medicine (Baltimore) ; 99(15): e19746, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32282735

RESUMO

RATIONALE: Toxic shock syndrome (TSS) typically is an acute onset multi-organ infection caused by TSS toxin-1 producing Staphylococcus aureus. Herein we describe a highly unusual case report. PATIENT CONCERNS: A male patient self-referred to the University of Minnesota Hospital with a chronic history of S aureus infection with accompanying fever, hypotension, and nonhealing, football-sized lesion on his leg. DIAGNOSIS: An unusual case presentation of TSS/hyperimmunoglobulin E syndrome is described. The patient had a leg wound from which TSS toxin-1 S aureus was isolated. The patient exhibited characteristic skewing of T cells to those with variable region, ß-chain T cell receptor-2. Other patients have been seen with related presentations. INTERVENTIONS: The following therapeutic regimen was instituted: vigorous antibacterial scrubs several times daily plus intravenous Ancef 3 days each month; intravenous infusions of immunoglobulin G infusions (28 gm) every 3 weeks; and weekly subcutaneous injections of recombinant granulocyte colony-stimulating factor. OUTCOME: Improvement was obvious within 3 months: no further cellulitic episodes occurred; the patient regained 95 pounds in 9 months; blanching and cyanosis of fingers disappeared within 3 months as did intractable pain although mild hypesthesias continued for 2 years; erythroderma resolved, and repeat skin biopsies performed after 2 years no longer demonstrated T cell receptor skewing. Although IgE levels have not completely returned to normal, the patient remains in excellent health. LESSONS: We propose that staphylococcal TSST-1 was responsible for the serious problems suffered by this patient as suggested by the following features: rapid onset of chronic, life-threatening, disorder that began with an episode of staphylococcal sepsis; the extraordinary elevation of IgE levels in this previously non-atopic individual; the acquired severe granulocyte chemotactic defect that accompanied this hyperimmunoglobulinemia ("Job Syndrome") with its accompanying wound-healing defect; and the striking diffuse erythroderma, including palmar erythema ("Red Man Syndrome") with hypotension and fever that also characterizes TSS.


Assuntos
Síndrome de Job/microbiologia , Choque Séptico/microbiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/isolamento & purificação , Administração Intravenosa , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Cefazolina/administração & dosagem , Cefazolina/uso terapêutico , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Humanos , Imunoglobulina G/administração & dosagem , Imunoglobulina G/uso terapêutico , Infusões Intravenosas , Injeções Subcutâneas , Síndrome de Job/diagnóstico , Síndrome de Job/etiologia , Perna (Membro)/patologia , Masculino , Pessoa de Meia-Idade , Choque Séptico/diagnóstico , Choque Séptico/etiologia , Infecções Estafilocócicas/complicações , Infecções Estafilocócicas/patologia , Resultado do Tratamento , Ferimentos e Lesões/microbiologia
9.
J Agric Food Chem ; 68(6): 1621-1633, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-31967468

RESUMO

Collagen peptides can promote wound healing and are closely related to microbiome colonization. We investigated the relationship among collagen peptides, wound healing, and wound microflora colonization by administering the murine wound model with Salmo salar skin collagen peptides (Ss-SCPs) and Tilapia nilotica skin collagen peptides (Tn-SCPs). We analyzed the vascular endothelial growth factor (VEGF), fibroblast growth factors (ß-FGF), pattern recognition receptor (NOD2), antimicrobial peptides (ß-defence14, BD14), proinflammatory (TNF-α, IL-6, and IL-8) and anti-inflammatory (IL-10) cytokines, macrophages, neutrophil infiltration levels, and microbial communities in the rat wound. The healing rates of the Ss-SCP- and Tn-SCP-treated groups were significantly accelerated, associated with decreased TNF-α, IL-6, and IL-8 and upregulated BD14, NOD2, IL-10, VEGF, and ß-FGF. Accelerated healing in the collagen peptide group shows that the wound microflora such as Leuconostoc, Enterococcus, and Bacillus have a positive effect on wound healing (P < 0.01). Other microbiome species such as Stenotrophomonas, Bradyrhizobium, Sphingomonas, and Phyllobacterium had a negative influence and decreased colonization (P < 0.01). Altogether, these studies show that collagen peptide could upregulate wound NOD2 and BD14, which were implicated in microflora colonization regulation in the wound tissue and promoted wound healing by controlling the inflammatory reaction and increasing wound angiogenesis and collagen deposition.


Assuntos
Colágeno/química , Proteínas de Peixes/química , Microbiota/efeitos dos fármacos , Proteína Adaptadora de Sinalização NOD2/genética , Peptídeos/administração & dosagem , Pele/química , Ferimentos e Lesões/fisiopatologia , beta-Defensinas/genética , Administração Cutânea , Animais , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/isolamento & purificação , Ciclídeos , Fatores de Crescimento de Fibroblastos/genética , Fatores de Crescimento de Fibroblastos/imunologia , Humanos , Interleucina-10/genética , Interleucina-10/imunologia , Masculino , Camundongos , Proteína Adaptadora de Sinalização NOD2/imunologia , Peptídeos/química , Ratos , Ratos Sprague-Dawley , Salmo salar , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/imunologia , Cicatrização/efeitos dos fármacos , Ferimentos e Lesões/tratamento farmacológico , Ferimentos e Lesões/imunologia , Ferimentos e Lesões/microbiologia , beta-Defensinas/imunologia
10.
Nat Chem Biol ; 16(2): 126-133, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31792444

RESUMO

Materials can be made multifunctional by embedding them with living cells that perform sensing, synthesis, energy production, and physical movement. A challenge is that the conditions needed for living cells are not conducive to materials processing and require continuous water and nutrients. Here, we present a three dimensional (3D) printer that can mix material and cell streams to build 3D objects. Bacillus subtilis spores were printed within the material and germinated on its exterior surface, including spontaneously in new cracks. The material was resilient to extreme stresses, including desiccation, solvents, osmolarity, pH, ultraviolet light, and γ-radiation. Genetic engineering enabled the bacteria to respond to stimuli or produce chemicals on demand. As a demonstration, we printed custom-shaped hydrogels containing bacteria that can sense or kill Staphylococcus aureus, a causative agent of infections. This work demonstrates materials endued with living functions that can be used in applications that require storage or exposure to environmental stresses.


Assuntos
Bacillus subtilis , Impressão Tridimensional , Esporos Bacterianos , Ferimentos e Lesões/microbiologia , Antibacterianos/metabolismo , Bacillus subtilis/genética , Fenômenos Fisiológicos Bacterianos , Desenho de Equipamento , Escherichia coli , Concentração de Íons de Hidrogênio , Teste de Materiais , Microrganismos Geneticamente Modificados , Impressão Tridimensional/instrumentação , Percepção de Quorum , Sefarose/química , Esporos Bacterianos/crescimento & desenvolvimento , Esporos Bacterianos/fisiologia , Staphylococcus aureus , Estresse Fisiológico , Temperatura , Ácido Vanílico/análise
11.
Int J Biol Macromol ; 143: 510-520, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31778697

RESUMO

Polyurethane combined (PUC) foam dressings with various biomacromolecules were fabricated with the adsorption of asiaticoside and silver nanoparticles for traumatic wound treatment. Biomacromolecules had varying effects on physicochemical and mechanical properties of PU foam. With 2% incorporation, starches, high molecular weight chitosan and gelatin provided stiffer and more porous foams while carboxymethylcellulose had the highest compression strength but the lowest water vapor transmission. High water absorption was from foams with carboxymethylcellulose, alginate, hydroxypropyl methylcellulose and low molecular weight chitosan. Increasing the concentrations up to 12% had more prominent effect. However, powdery surface was noticed with poorer tensile properties that 6% incorporation was selected. FTIR spectra and DSC thermograms suggested interaction of PU formulation with biomacromolecules. EDS analysis confirmed existence of active compounds while acceptable stability was from sterilized PUC foam with alginate. On healthy volunteers, this selected foam dressing caused no skin irritation and retained moisture comparable to commercial product. In patients with traumatic dermal wounds, healing improvement with shorter wound closure time, higher reepithelialization and less pain score were from the selected foam dressing compared to standard gauze soaked with chlorhexidine. This PU-alginate combined foam dressing adsorbed with asiaticoside and silver nanoparticles proved advantages for traumatic dermal wound management.


Assuntos
Derme , Sistemas de Liberação de Medicamentos , Infecções Pneumocócicas , Poliuretanos , Streptococcus pneumoniae/metabolismo , Triterpenos , Infecção dos Ferimentos , Ferimentos e Lesões , Animais , Derme/metabolismo , Derme/microbiologia , Derme/patologia , Avaliação Pré-Clínica de Medicamentos , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Infecções Pneumocócicas/tratamento farmacológico , Infecções Pneumocócicas/metabolismo , Infecções Pneumocócicas/microbiologia , Infecções Pneumocócicas/patologia , Poliuretanos/química , Poliuretanos/farmacocinética , Poliuretanos/farmacologia , Células RAW 264.7 , Triterpenos/química , Triterpenos/farmacocinética , Triterpenos/farmacologia , Infecção dos Ferimentos/tratamento farmacológico , Infecção dos Ferimentos/metabolismo , Infecção dos Ferimentos/microbiologia , Infecção dos Ferimentos/patologia , Ferimentos e Lesões/tratamento farmacológico , Ferimentos e Lesões/metabolismo , Ferimentos e Lesões/microbiologia , Ferimentos e Lesões/patologia
12.
Am J Vet Res ; 81(1): 84-90, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31887087

RESUMO

OBJECTIVE: To investigate in vitro effects of triclosan coating of suture materials on the growth of clinically relevant bacteria isolated from wounds in dogs. SAMPLE: 6 types of suture material and 10 isolates each of methicillin-susceptible Staphylococcus pseudintermedius, methicillin-resistant S pseudintermedius, Escherichia coli, and AmpC ß-lactamase and extended-spectrum ß-lactamase-producing E coli from clinical wound infections. PROCEDURES: Isolates were cultured on Mueller-Hinton agar with 3 types of triclosan-coated suture, uncoated counterparts of the same suture types, and positive and negative controls. Zones of inhibition (ZOIs) were measured after overnight incubation. Sustained antimicrobial activity assays were performed with susceptible isolates. The ZOI measurements and durations of sustained antimicrobial activity were compared among suture types and isolates by statistical methods. Suture surface characteristics and bacterial adherence were evaluated qualitatively with scanning electron microscopy. RESULTS: ZOIs were generated only by triclosan-coated materials; triclosan-coated suture had sustained antimicrobial activity (inhibition) for 3 to 29 days against all tested pathogens. The ZOIs around triclosan-coated suture were significantly greater for S pseudintermedius isolates than for E coli isolates. Bacterial adherence to uncoated polyglactin-910 was greatest, followed by triclosan-coated polyglactin-910, and then uncoated monofilament sutures, with least adherence to coated monofilament sutures. CONCLUSIONS AND CLINICAL RELEVANCE: Surface characteristics of suture materials may be as important or more important than triclosan coating for microbial inhibition; however, triclosan coating appeared to affect bacterial adherence for multifilament sutures. Triclosan-coated, particularly monofilament, sutures inhibited pathogens commonly isolated from wounds of dogs, including multidrug-resistant bacteria. Further studies are required to assess clinical efficacy of triclosan-coated suture materials in vivo.


Assuntos
Bactérias/efeitos dos fármacos , Suturas/veterinária , Triclosan/farmacologia , Ferimentos e Lesões/veterinária , Animais , Anti-Infecciosos Locais/administração & dosagem , Anti-Infecciosos Locais/farmacologia , Bactérias/isolamento & purificação , Bactérias/ultraestrutura , Aderência Bacteriana/efeitos dos fármacos , Cães , Meticilina/farmacologia , Microscopia Eletrônica de Varredura , Poliglactina 910 , Propriedades de Superfície , Suturas/microbiologia , Triclosan/administração & dosagem , Ferimentos e Lesões/microbiologia
13.
J Infect Dis ; 221(4): 618-626, 2020 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-31565732

RESUMO

BACKGROUND: Antimicrobial resistance is a significant concern to public health, and there is a pressing need to develop novel antimicrobial therapeutic modalities. METHODS: In this study, we investigated the capacity for quinine hydrochloride (Q-HCL) to enhance the antimicrobial effects of antimicrobial blue light ([aBL] 405 nm wavelength) against multidrug-resistant (MDR) Gram-negative bacteria in vitro and in vivo. RESULTS: Our findings demonstrated the significant improvement in the inactivation of MDR Pseudomonas aeruginosa and Acinetobacter baumannii (planktonic cells and biofilms) when aBL was illuminated during Q-HCL exposure. Furthermore, the addition of Q-HCL significantly potentiated the antimicrobial effects of aBL in a mouse skin abrasion infection model. In addition, combined exposure of aBL and Q-HCL did not result in any significant apoptosis when exposed to uninfected mouse skin. CONCLUSIONS: In conclusion, aBL in combination with Q-HCL may offer a novel approach for the treatment of infections caused by MDR bacteria.


Assuntos
Infecções por Acinetobacter/tratamento farmacológico , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/efeitos da radiação , Antibacterianos/uso terapêutico , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos da radiação , Quinina/uso terapêutico , Terapia Ultravioleta/métodos , Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/fisiologia , Animais , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Biofilmes/efeitos da radiação , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla/efeitos da radiação , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Plâncton/microbiologia , Pseudomonas aeruginosa/fisiologia , Quinina/farmacologia , Pele/lesões , Pele/microbiologia , Pele/patologia , Resultado do Tratamento , Ferimentos e Lesões/microbiologia
14.
J Infect Chemother ; 26(2): 308-311, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31680035

RESUMO

Acinetobacter spp. are known to be a cause of nosocomial infections and to have diverse mechanisms of resistance to antimicrobials. Here, we report the case of a patient who presented to our emergency department with necrotizing fasciitis due to Acinetobacter junii as confirmed by Matrix-Assisted Laser Desorption/Ionization Time-of-Flight mass spectrometry (MALDI-TOF MS). Patients with liver cirrhosis are susceptible to gram-negative infection. Moreover, although Acinetobacter spp. infection is best known to be a cause of combat-related-skin and soft-tissue infections, we propose that medical professionals need to consider the presence of these potentially multi-drug-resistant, gram-negative pathogens when treating patients with liver cirrhosis who present with severe soft-tissue infections. To our knowledge, this is the first case report of severe-skin and soft-tissue infections caused by A. junii.


Assuntos
Infecções por Acinetobacter/diagnóstico , Acinetobacter/isolamento & purificação , Fasciite Necrosante/diagnóstico , Fasciite Necrosante/microbiologia , Cirrose Hepática/complicações , Infecções por Acinetobacter/complicações , Infecções por Acinetobacter/tratamento farmacológico , Infecções por Acinetobacter/microbiologia , Idoso , Antibacterianos/uso terapêutico , Infecções Comunitárias Adquiridas/diagnóstico , Infecções Comunitárias Adquiridas/tratamento farmacológico , Infecções Comunitárias Adquiridas/microbiologia , Fasciite Necrosante/complicações , Fasciite Necrosante/tratamento farmacológico , Humanos , Perna (Membro)/patologia , Masculino , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Resultado do Tratamento , Ferimentos e Lesões/microbiologia
15.
Surg Infect (Larchmt) ; 21(1): 15-22, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31210580

RESUMO

Background: Multi-drug resistance is considered a serious health threat particularly in the intensive care unit (ICU) setting. Studies evaluating multi-drug-resistant (MDR) pathogens in critically ill trauma patients are limited. The objectives were to describe the incidence of MDR, extensive-drug-resistant (XDR), and pan-drug-resistant (PDR) organism growth in ICU patients admitted with traumatic injuries and to identify any risk factors associated with MDR growth. Patients and Methods: This was a retrospective single-center cohort study of all ICU adult patients identified via the institution's trauma registry from January 1, 2016 to August 31, 2017. Patients were included if they had positive culture growth with susceptibility data taken during the index hospitalization. Patients were excluded if their cultures were drawn within 48 hours of emergency department triage. Study groups were defined based on the presence of at least one MDR pathogen during the index hospitalization. Results: A total of 2,578 charts were reviewed and 95 patients (mean age, 60 years; 66 males [69%]) with 201 total cultures were included. The majority of positive cultures were from respiratory (69%) and urinary (16%) sources. Of the 201 positive cultures, the majority of species identified was Enterobacteriaceae (47%), Staphylococcus (32%), Enterococcus (7%), Acinetobacter (5%), and Pseudomonas (3%). Of the 95 patients with positive cultures, the incidence of MDR, XDR, and PDR organisms was found to be 31%, 17%, and 0%, respectively. Augmented renal clearance (ARC) was the only risk factor associated with an increased risk for MDR organism growth (adjusted odds ratio 9.78, 95% confidence interval [CI] 2.56-37.41; p = 0.001). Conclusions: In this cohort of critically ill trauma patients, the incidence of an MDR pathogen occurred in 31% of patients. This is the first study to find an association of ARC and multi-drug resistance, which should be further validated as a potential cause for MDR organisms.


Assuntos
Estado Terminal/epidemiologia , Farmacorresistência Bacteriana Múltipla , Ferimentos e Lesões/complicações , Infecções Bacterianas/tratamento farmacológico , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Centros de Traumatologia/estatística & dados numéricos , Ferimentos e Lesões/microbiologia
16.
Sci Rep ; 9(1): 19318, 2019 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-31848388

RESUMO

A balanced redox state is critical for proper healing. Although human chronic wounds are characterized by high levels of oxidative stress (OS), whether OS levels are critical for chronic wound development is not known. For these studies, we used our chronic wound model in diabetic mice that has similar characteristics as human chronic wounds, including naturally developed biofilm. We hypothesize that OS levels in wound tissues are critical for chronic wound initiation and development. We show that increased OS levels in the wound correlate with increased chronicity. Moreover, without increased OS levels, biofilm taken from chronic wounds and placed in new excision wounds do not create chronic wounds. Similarly, high OS levels in the wound tissue in the absence of the skin microbiome do not lead to chronic wounds. These findings show that both high OS levels and bacteria are needed for chronic wound initiation and development. In conclusion, OS levels in the wound at time of injury are critical for biofilm formation and chronic wound development and may be a good predictor of the degree of wound chronicity. Treating such wounds might be accomplished by managing OS levels with antioxidants combined with manipulation of the skin microbiome after debridement.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Microbiota/genética , Estresse Oxidativo/genética , Ferimentos e Lesões/metabolismo , Animais , Antioxidantes/metabolismo , Biofilmes/crescimento & desenvolvimento , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/microbiologia , Diabetes Mellitus Experimental/patologia , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos Endogâmicos NOD , Pele/microbiologia , Pele/patologia , Cicatrização/genética , Infecção dos Ferimentos , Ferimentos e Lesões/etiologia , Ferimentos e Lesões/genética , Ferimentos e Lesões/microbiologia
17.
FEMS Microbiol Lett ; 366(16)2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31580434

RESUMO

A simple and facile way of using biogenic silver nanoparticles (BSNP) (10-20 nm) was developed for wound healing acceleration and suppression of wound infections. The BSNP were formulated in an ointment base, and the study to accelerate the wound healing process was conducted in a rat. The pH of the BSNP ointment, pH 6.8 ± 0.5, lies in normal pH range of the human skin, with good spreadability and diffusibility. The wound closure rate, as a percentage, was highest at day 3 for a BSNP ointment-treated wound at 22.77 ± 1.60%, while in an untreated control the rate was 10.99 ± 1.74%, for Betadine 14.73 ± 2.36% and for Soframycin 18.55 ± 1.37%, compared with day 0. A similar pattern of wound closure rate was found at days 7 and 11. The antibacterial activity of BSNP was evaluated against wound-infection-causing bacteria Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli by the agar diffusion method. The total bacterial counts in the wound area were enumerated by the colony forming unit method. The lowest number of bacterial counts was found in the BSNP-treated wound compared with the other groups. BSNP treatment at 7.5% concentration enhanced migration of fibroblasts in a scratch assay. These findings reveal BSNP as an efficient contrivance for wound healing acceleration and as an eco-friendly alternative therapeutic antimicrobial agent.


Assuntos
Anti-Infecciosos/administração & dosagem , Nanopartículas Metálicas/administração & dosagem , Nanomedicina/métodos , Prata/administração & dosagem , Cicatrização/efeitos dos fármacos , Infecção dos Ferimentos/prevenção & controle , Ferimentos e Lesões/tratamento farmacológico , Animais , Contagem de Colônia Microbiana , Modelos Animais de Doenças , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/prevenção & controle , Pomadas/administração & dosagem , Infecções por Pseudomonas/prevenção & controle , Pseudomonas aeruginosa/isolamento & purificação , Ratos , Infecções Estafilocócicas/prevenção & controle , Staphylococcus aureus/isolamento & purificação , Resultado do Tratamento , Infecção dos Ferimentos/tratamento farmacológico , Infecção dos Ferimentos/microbiologia , Ferimentos e Lesões/microbiologia
18.
Sci Rep ; 9(1): 14338, 2019 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-31605019

RESUMO

Neisseria animaloris is considered to be a commensal of the canine and feline oral cavities. It is able to cause systemic infections in animals as well as humans, usually after a biting trauma has occurred. We recovered N. animaloris from chronically inflamed bite wounds on pectoral fins and tailstocks, from lungs and other internal organs of eight harbour porpoises. Gross and histopathological evidence suggest that fatal disseminated N. animaloris infections had occurred due to traumatic injury from grey seals. We therefore conclude that these porpoises survived a grey seal predatory attack, with the bite lesions representing the subsequent portal of entry for bacteria to infect the animals causing abscesses in multiple tissues, and eventually death. We demonstrate that forensic microbiology provides a useful tool for linking a perpetrator to its victim. Moreover, N. animaloris should be added to the list of potential zoonotic bacteria following interactions with seals, as the finding of systemic transfer to the lungs and other tissues of the harbour porpoises may suggest a potential to do likewise in humans.


Assuntos
Genética Forense , Neisseria/patogenicidade , Focas Verdadeiras/lesões , Ferimentos e Lesões/genética , Animais , Animais Selvagens/genética , Animais Selvagens/lesões , Animais Selvagens/microbiologia , Neisseria/genética , Focas Verdadeiras/genética , Focas Verdadeiras/microbiologia , Ferimentos e Lesões/microbiologia , Zoonoses/genética , Zoonoses/microbiologia
19.
Nat Microbiol ; 4(12): 2146-2154, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31611643

RESUMO

A slimy, hydrated mucus gel lines all wet epithelia in the human body, including the eyes, lungs, and gastrointestinal and urogenital tracts. Mucus forms the first line of defence while housing trillions of microorganisms that constitute the microbiota1. Rarely do these microorganisms cause infections in healthy mucus1, suggesting that mechanisms exist in the mucus layer that regulate virulence. Using the bacterium Pseudomonas aeruginosa and a three-dimensional (3D) laboratory model of native mucus, we determined that exposure to mucus triggers downregulation of virulence genes that are involved in quorum sensing, siderophore biosynthesis and toxin secretion, and rapidly disintegrates biofilms-a hallmark of mucosal infections. This phenotypic switch is triggered by mucins, which are polymers that are densely grafted with O-linked glycans that form the 3D scaffold inside mucus. Here, we show that isolated mucins act at various scales, suppressing distinct virulence pathways, promoting a planktonic lifestyle, reducing cytotoxicity to human epithelia in vitro and attenuating infection in a porcine burn model. Other viscous polymer solutions lack the same effect, indicating that the regulatory function of mucin does not result from its polymeric structure alone. We identify that interactions with P. aeruginosa are mediated by mucin-associated glycans (mucin glycans). By isolating glycans from the mucin backbone, we assessed the collective activity of hundreds of complex structures in solution. Similar to their grafted counterparts, free mucin glycans potently regulate bacterial phenotypes even at relatively low concentrations. This regulatory function is likely dependent on glycan complexity, as monosaccharides do not attenuate virulence. Thus, mucin glycans are potent host signals that 'tame' microorganisms, rendering them less harmful to the host.


Assuntos
Interações Hospedeiro-Patógeno , Mucinas/química , Muco/microbiologia , Polissacarídeos/química , Pseudomonas aeruginosa/patogenicidade , Animais , Biofilmes , Queimaduras/microbiologia , Células Epiteliais/microbiologia , Feminino , Células HT29 , Humanos , Muco/química , Pseudomonas aeruginosa/efeitos dos fármacos , Percepção de Quorum , Suínos , Virulência/genética , Ferimentos e Lesões/microbiologia
20.
Int Wound J ; 16(5): 1214-1221, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31483575

RESUMO

The use of negative-pressure wound therapy (NPWT) has displayed significant clinical benefits in the healing of infected wounds. However, the effects of NPWT on bacterial colonisation and infection of traumatic wounds has been controversial. The aim of this study is to evaluate the impact of NPWT treatment in rabbits with a contaminated full-thickness wound on bacterial behaviour, including colony morphology, spatial distribution, fissional proliferation, and bacterial bioburden. Full-thickness wounds were created on the back of rabbits, and were inoculated with bioluminescent Staphylococcus aureus. The wounds were treated with sterile gauze dressings and NPWT with continuous negative pressure (-125 mm Hg). Wound samples were harvested on days 0 (6 hours after bacterial inoculation), 2, 4, 6, and 8 at the centre of wound beds before irrigation. Scanning electron microscopy and transmission electron microscopy (TEM) analyses were performed to determine the characteristic bacteriology. Laser scanning confocal microscopy was performed to obtain bioluminescent images, which were used to observe spatial distribution of the GFP-labelled S. aureus within the tissue and quantify the bacterial bioburden. NPWT resulted in sparse amounts of scattered bacteria on the wound surface or as sparsely spaced single colonies within the tissue. Wound bioburden on day 8 in the NPWT and gauze groups was 34.6 ± 5.5% and 141.9 ± 15.4% of the baseline values (N = 6), respectively (P < .0001). TEM showed a lack of S. aureus active fission within NPWT-treated tissue. NPWT can impact S. aureus colony morphology and spatial distribution both on the surface and within wound tissue, and reduce S. aureus as early as 48 hours after therapy initiation. Additionally, NPWT inhibits bacterial fissional proliferation in microcolonies.


Assuntos
Tratamento de Ferimentos com Pressão Negativa/métodos , Pele/ultraestrutura , Infecções Estafilocócicas/terapia , Cicatrização/fisiologia , Infecção dos Ferimentos/terapia , Ferimentos e Lesões/terapia , Animais , Modelos Animais de Doenças , Feminino , Microbiota/fisiologia , Microscopia Confocal/métodos , Microscopia Eletrônica , Microscopia Eletrônica de Transmissão/métodos , Coelhos , Distribuição Aleatória , Medição de Risco , Pele/microbiologia , Resultado do Tratamento , Ferimentos e Lesões/microbiologia
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