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1.
Biomater Adv ; 151: 213488, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37285725

RESUMO

In chronic wound (CW) scenarios, Staphylococcus aureus-induced infections are very prevalent. This leads to abnormal inflammatory processes, in which proteolytic enzymes, such as human neutrophil elastase (HNE), become highly expressed. Alanine-Alanine-Proline-Valine (AAPV) is an antimicrobial tetrapeptide capable of suppressing the HNE activity, restoring its expression to standard rates. Here, we proposed the incorporation of the peptide AAPV within an innovative co-axial drug delivery system, in which the peptide liberation was controlled by N-carboxymethyl chitosan (NCMC) solubilization, a pH-sensitive antimicrobial polymer effective against Staphylococcus aureus. The microfibers' core was composed of polycaprolactone (PCL), a mechanically resilient polymer, and AAPV, while the shell was made of the highly hydrated and absorbent sodium alginate (SA) and NCMC, responsive to neutral-basic pH (characteristic of CW). NCMC was loaded at twice its minimum bactericidal concentration (6.144 mg/mL) against S. aureus, while AAPV was loaded at its maximum inhibitory concentration against HNE (50 µg/mL), and the production of fibers with a core-shell structure, in which all components could be detected (directly or indirectly), was confirmed. Core-shell fibers were characterized as flexible and mechanically resilient, and structurally stable after 28-days of immersion in physiological-like environments. Time-kill kinetics evaluations revealed the effective action of NCMC against S. aureus, while elastase inhibitory activity examinations proved the ability of AAPV to reduce HNE levels. Cell biology testing confirmed the safety of the engineered fiber system for human tissue contact, with fibroblast-like cells and human keratinocytes maintaining their morphology while in contact with the produced fibers. Data confirmed the engineered drug delivery platform as potentially effective for applications in CW care.


Assuntos
Quitosana , Infecções Estafilocócicas , Humanos , Alginatos/farmacologia , Quitosana/farmacologia , Quitosana/química , Elastase de Leucócito/metabolismo , Elastase de Leucócito/farmacologia , Peptídeos/farmacologia , Polímeros/farmacologia , Staphylococcus aureus/metabolismo , Valina/farmacologia , Ferimentos e Lesões/complicações , Ferimentos e Lesões/microbiologia , Ferimentos e Lesões/terapia , Cicatrização/efeitos dos fármacos , Cicatrização/fisiologia
2.
Arch Razi Inst ; 78(1): 269-276, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-37312720

RESUMO

Many infections produced by multidrug-resistant (MDR) Klebsiella pneumoniae are the main cause of death and treatment restrictions worldwide. In K. pneumoniae, the efflux pump system is dangerous in drug resistance. Therefore, this study was designed to investigate the involvement of the AcrA and AcrB efflux pumps in antibiotic resistance in Klebsiella pneumoniae isolated from wound patients. During June 2021-February 2022, 87 clinical isolates of Klebsiella pneumonia bacteria were obtained from wound samples patients consulted to the hospitals in AL-Diwaniyah province, Iraq. The disc diffusion method performed an antibiotic susceptibility test after microbiological/biochemical identification. The polymerase chain reaction (PCR) technique was used to examine efflux genes' prevalence (acrA and acrB). The results showed that resistance to Carbenicillin 72 (82.7%), Erythromycin 66 (75.8%), Rifampin 58 (66.6%), Ceftazidime 52 (59.7%), Cefotaxime 44 (50.5%), Novobiocin 38 (43.6%), Tetracycline 32 (36.7%), Ciprofloxacin 22 (25.2%), Gentamicin 16 (18.3%), Nitrofurantoin 6 (10.3%) in Klebsiella pneumoniae isolates. The PCR procedure revealed that the occurrence of the acrA and acrB genes is 55 (100%) and 55 (100%), respectively. The findings of this investigation show that the AcrA and AcrB efflux pumps play a crucial character in antibiotic resistance in multidrug-resistant Klebsiella pneumoniae bacterial isolates. As a result of the unintentional transmission of antimicrobial resistance genes, precise detection of resistance genes using molecular approaches is required to switch the extent of resistant strains.


Assuntos
Cefotaxima , Farmacorresistência Bacteriana Múltipla , Klebsiella pneumoniae , Humanos , Ceftazidima , Ciprofloxacina , Nitrofurantoína , Farmacorresistência Bacteriana Múltipla/genética , Proteínas de Bactérias/genética , Ferimentos e Lesões/microbiologia , Ferimentos e Lesões/veterinária
3.
Nature ; 618(7964): 358-364, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37225987

RESUMO

The ability to switch between different lifestyles allows bacterial pathogens to thrive in diverse ecological niches1,2. However, a molecular understanding of their lifestyle changes within the human host is lacking. Here, by directly examining bacterial gene expression in human-derived samples, we discover a gene that orchestrates the transition between chronic and acute infection in the opportunistic pathogen Pseudomonas aeruginosa. The expression level of this gene, here named sicX, is the highest of the P. aeruginosa genes expressed in human chronic wound and cystic fibrosis infections, but it is expressed at extremely low levels during standard laboratory growth. We show that sicX encodes a small RNA that is strongly induced by low-oxygen conditions and post-transcriptionally regulates anaerobic ubiquinone biosynthesis. Deletion of sicX causes P. aeruginosa to switch from a chronic to an acute lifestyle in multiple mammalian models of infection. Notably, sicX is also a biomarker for this chronic-to-acute transition, as it is the most downregulated gene when a chronic infection is dispersed to cause acute septicaemia. This work solves a decades-old question regarding the molecular basis underlying the chronic-to-acute switch in P. aeruginosa and suggests oxygen as a primary environmental driver of acute lethality.


Assuntos
Doença Aguda , Doença Crônica , Genes Bacterianos , Oxigênio , Infecções por Pseudomonas , Pseudomonas aeruginosa , RNA Bacteriano , Animais , Humanos , Oxigênio/metabolismo , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/patogenicidade , Infecções por Pseudomonas/complicações , Infecções por Pseudomonas/microbiologia , Infecções por Pseudomonas/patologia , RNA Bacteriano/genética , RNA Bacteriano/metabolismo , Fibrose Cística/microbiologia , Ferimentos e Lesões/microbiologia , Ubiquinona/biossíntese , Anaerobiose , Genes Bacterianos/genética , Sepse/complicações , Sepse/microbiologia
4.
NPJ Biofilms Microbiomes ; 8(1): 49, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35705574

RESUMO

A new technique was used to measure the viscoelasticity of in vivo Pseudomonas aeruginosa biofilms. This was done through ex vivo microrheology measurements of in vivo biofilms excised from mouse wound beds. To our knowledge, this is the first time that the mechanics of in vivo biofilms have been measured. In vivo results are then compared to typical in vitro measurements. Biofilms grown in vivo are more relatively elastic than those grown in a wound-like medium in vitro but exhibited similar compliance. Using various genetically mutated P. aeruginosa strains, it is observed that the contributions of the exopolysaccharides Pel, Psl, and alginate to biofilm viscoelasticity were different for the biofilms grown in vitro and in vivo. In vitro experiments with collagen containing medium suggest this likely arises from the incorporation of host material, most notably collagen, into the matrix of the biofilm when it is grown in vivo. Taken together with earlier studies that examined the in vitro effects of collagen on mechanical properties, we conclude that collagen may, in some cases, be the dominant contributor to biofilm viscoelasticity in vivo.


Assuntos
Biofilmes , Pseudomonas aeruginosa , Animais , Colágeno/metabolismo , Colágeno/farmacologia , Camundongos , Polissacarídeos Bacterianos/metabolismo , Pseudomonas aeruginosa/fisiologia , Substâncias Viscoelásticas , Ferimentos e Lesões/microbiologia
5.
BMC Vet Res ; 18(1): 197, 2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35614464

RESUMO

A pathogenic strain of Macrococcus caseolyticus (M. caseolyticus) was isolated from wounds infection during an investigation on donkeys in Khartoum State. (122) samples were collected from external wounds (head, abdomen, back and leg) during different seasons. One isolate (124B) was identified using whole-genome sequence analysis. RAST software identified 31 virulent genes of disease and defense, including methicillin-resistant genes, TatR family and ANT(4')-Ib. Plasmid rep22 was identified by PlasmidFindet-2.0 Server and a CRISPR. MILST-2.0 predicted many novel alleles. NCBI notated the genome as a novel M. caseolyticus strain (DaniaSudan). The MLST-tree-V1 revealed that DaniaSudan and KM0211a strains were interrelated. Strain DaniaSudan was resistant to ciprofloxacin, ceftazidime, erythromycin, oxacillin, clindamycin and kanamycin. Mice modeling showed bacteremia and many clinical signs (swelling, allergy, wounds, and hair loss). Enlargement, hyperemia, adhesions and abscesses were observed in many organs.Constructive conclusionThe prevalence of the strain was 4.73%, with significant differences between collection seasons and locations of wounds. A highly significant association between doses (105 CFU/ml, 102 CFU/ml, Intra-peritoneum and sub-cutaneous) and swelling, developing of allergy and loss of hair (p = 0.001, p = 0.000 and p = 0.005) respectively were seen.This result represents the first report of pathogenic strains of M. caseolyticus worldwide.


Assuntos
Doenças dos Roedores , Staphylococcaceae , Ferimentos e Lesões , Animais , Antibacterianos/farmacologia , Equidae/microbiologia , Hipersensibilidade/etiologia , Hipersensibilidade/veterinária , Camundongos , Testes de Sensibilidade Microbiana/veterinária , Tipagem de Sequências Multilocus/veterinária , Prevalência , Staphylococcaceae/genética , Sudão , Ferimentos e Lesões/microbiologia
6.
Drug Deliv ; 29(1): 1086-1099, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35373683

RESUMO

The development of novel wound dressings, such as aerogels, with rapid hemostasis and bactericidal capacities for pre-hospital care is necessary. To prevent the occurrence of bacterial resistance, antibacterial photodynamic therapy (aPDT) with broad-spectrum antibacterial ability and negligible bacterial resistance has been intensively studied. However, photosensitizers often suffer from poor water solubility, short singlet oxygen (1O2) half-life and restricted 1O2 diffusion distance. Herein, sodium alginate was covalently modified by photosensitizers and phenylboronic acid, and cross-linked by Ca(II) ions to generate SA@TPAPP@PBA aerogel after lyophilization as an antibacterial photodynamic wound dressing. Afterwards, its photodynamic and bacterial capture activities were intensively evaluated. Furthermore, its hemostasis and bactericidal efficiency against Staphylococcus aureus were assessed via in vitro and in vivo assays. First, chemical immobilization of photosensitizers led to an enhancement of its solubility. Moreover, it showed an excellent hemostasis capacity. Due to the formation of reversible covalent bonds between phenylboronic acid and diol groups on bacterial cell surface, the aerogel could capture S. aureus tightly and dramatically enhance aPDT. To sum up, the prepared aerogel illustrated excellent hemostasis capacity and antibacterial ability against S. aureus. Therefore, they have great potential to be utilized as wound dressing in clinical trials.


Assuntos
Alginatos , Fotoquimioterapia , Alginatos/química , Antibacterianos/química , Antibacterianos/farmacologia , Bandagens , Géis , Staphylococcus aureus , Ferimentos e Lesões/microbiologia , Ferimentos e Lesões/terapia
7.
Pak J Pharm Sci ; 35(1(Supplementary)): 305-311, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35228192

RESUMO

Pathogenic strains of Staphylococcus aureus are mostly resistant to methicillin and they can cause severe infections. The current study was planned to assess the food poisoning potential of pathogenic, methicillin resistant Staphylococcus aureus by molecular detection of enterotoxin A (Eta) gene. A total of 100 septic wound samples from patients admitted in surgical ward (n=50) and burn unit (n=50) of Mayo Hospital Lahore were collected aseptically. These samples were processed primarily for bacterial growth on nutrient agar and purified on mannitol salt agar where twenty (20) samples showed pin-point colonies with yellow discoloration of media. Moreover, isolates were further characterized on the basis of microscopic appearance and biochemical assays where fourteen (14) isolates were declared Staphylococcus. DNA of these isolates were subjected to 16S rRNA gene amplification and sequences of S. aureus were submitted to NCBI GenBank viz., MW344063.1, MW341438.1, MW344064.1, MW344065.1, MW341439.1, MW341440.1, MW345971.1, MW345972.1, MW345973.1, MW716458.1. All the isolates (n=10) demonstrated molecular confirmation of pathogenicity and methicillin resistance by amplification of Coa and mecA gene. Out of these ten isolates, three amplified enterotoxin A (Eta) gene were confirmed. It is concluded that enterotoxin A of S. aureus which causes food poisoning is present in pathogenic, methicillin resistant S. aureus isolated from various wounds infections.


Assuntos
Biomarcadores/metabolismo , Microbiologia de Alimentos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Intoxicação Alimentar Estafilocócica/diagnóstico , Ferimentos e Lesões/microbiologia , Humanos , Pacientes Internados , Staphylococcus aureus Resistente à Meticilina/genética , Filogenia
8.
Molecules ; 27(1)2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35011491

RESUMO

Mangifera indica can generate up to 60% of polluting by-products, including peels. However, it has been shown that flavonoids and mangiferin are mainly responsible for the antioxidant, anti-inflammatory, and antibacterial activities closely related to the wound-healing process. The chemical composition of MEMI (methanolic extract of M. indica) was analyzed by HPLC-DAD, as well as concentrations of total phenol (TPC) and flavonoids (TFC) and antioxidant activity (SA50). Wound-healing efficacy was determined by measurements of wound contraction, histological analysis, and tensiometric method; moreover, anti-inflammatory, antibacterial, and acute dermal toxicity (OECD 402) were also evaluated. Phenol, resorcinol, conjugated resorcinol, and mangiferin were detected. TPC, TFC, and SA50 were 136 mg GAE/g, 101.66 mg QE/g, and 36.33 µg/mL, respectively. Tensile strength and wound contraction closure did not show significant differences between MEMI and dexpanthenol groups. Histological analysis (after 14 days) shows a similar architecture between MEMI treatment and normal skin. MEMI exhibits a reduction in edema. Staphylococcus epidermidis had an MIC of 2 mg/mL, while Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli reached 4 mg/mL. The MEMI showed no signs of toxicity. Therefore, this study demonstrates multiple targets that flavonoids and mangiferin of MEMI may present during the healing process.


Assuntos
Mangifera/química , Extratos Vegetais , Cicatrização/efeitos dos fármacos , Ferimentos e Lesões , Animais , Modelos Animais de Doenças , Flavonoides/química , Flavonoides/farmacologia , Masculino , Camundongos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Ferimentos e Lesões/tratamento farmacológico , Ferimentos e Lesões/metabolismo , Ferimentos e Lesões/microbiologia , Xantonas/química , Xantonas/farmacologia
9.
Rev Rene (Online) ; 23: e78112, 2022. graf
Artigo em Português | LILACS, BDENF - Enfermagem | ID: biblio-1376108

RESUMO

RESUMO Objetivo identificar na literatura a formação do biofilme e o seu comportamento diante das intervenções em feridas cutâneas. Métodos revisão integrativa, realizada nas bases de dados Cumulative Index to Nursing and Allied Health Literature , Literatura Latino-Americana e do Caribe em Ciências da Saúde, EMBASE, Scopus, The Cochrane Library Collaboration , MEDLINE/PubMed e Science Direct, sem delimitação temporal. Foram selecionados 19 estudos. Avaliação das informações ocorreu de forma descritiva, confrontando com os achados pertinentes. Resultados os estudos da amostra foram publicados no idioma inglês e contemplaram três tipos de pesquisa de biofilme: dois clínicos, seis in vitro e 11 in vivo (animal). Incluíram-se três temas: criação de modelo biofilme (n=4), avaliação do biofilme (n=3), comportamento do biofilme diante de intervenções para o seu manejo (n=12). Conclusão efeitos prejudiciais do biofilme na cicatrização de feridas foram confirmados. Diversas intervenções foram capazes de reduzir e eliminar o biofilme nos modelos in vitro e in vivo . Contribuições para a prática constatou-se que avaliação clínica da lesão não permite identificar o biofilme, inclusive quando presente encontra-se abaixo da superfície da lesão. Este achado suscita reflexão por parte dos enfermeiros a respeito das intervenções adotadas para a remoção do biofilme.


ABSTRACT Objective to identify in the literature the biofilm formation and its behavior when faced with interventions in cutaneous wounds. Methods an integrative review, carried out in the Cumulative Index to Nursing and Allied Health Literature, Latin American and Caribbean Health Sciences Literature, EMBASE, Scopus, The Cochrane Library Collaboration, MEDLINE/PubMed and Science Direct databases, without temporal delimitation. Nineteen studies were selected. The information was evaluated descriptively, comparing it with the pertinent findings. Results the sample studies were published in English and included three types of biofilm research: two clinical, six in vitro and 11 in vivo (animal). Three themes were included: biofilm model creation (n=4), biofilm assessment (n=3), biofilm behavior before interventions for its management (n=12). Conclusion the detrimental effects of biofilm on wound healing have been confirmed. Several interventions were able to reduce and eliminate biofilm in in vitro and in vivo models. Contributions to practice it was found that clinical evaluation of the lesion does not allow the identification of biofilm, even when present; it is below the surface of the lesion. This finding raises reflection on the part of nurses regarding the interventions adopted for the removal of biofilm.


Assuntos
Humanos , Infecção dos Ferimentos/microbiologia , Ferimentos e Lesões/microbiologia , Biofilmes/crescimento & desenvolvimento , Infecção dos Ferimentos/terapia , Ferimentos e Lesões/terapia
10.
Sci Rep ; 11(1): 23181, 2021 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-34848752

RESUMO

The endemic strain of Leishmania donovani in Sri Lanka causes cutaneous leishmaniasis (CL) rather than more common visceral form. We have visualized biofilms and profiled the microbiome of lesions and unaffected skin in thirty-nine CL patients. Twenty-four lesions (61.5%) were biofilm-positive according to fluorescence in situ hybridization. Biopsies of biofilm-positive lesions were dominated by Pseudomonas, class Bacilli and Enterobacteriaceae and distinguished by significantly lower community evenness. Higher relative abundance of a class Bacilli OTU was detected in wound swabs versus contralateral skin. Wound swabs and biopsies had significantly distinct microbiome profiles and lower diversity compared to unaffected skin. Greater abundances of potentially pathogenic organisms were observed in wet ulcers, lesions with high parasite loads and large wounds. In summary, more than half of L. donovani associated CL wounds harboured biofilms and the wounds exhibited a distinct, less diverse, microbiome than unaffected skin.


Assuntos
Biofilmes , Leishmania donovani , Leishmaniose Cutânea/microbiologia , Microbiota , Ferimentos e Lesões/microbiologia , Adulto , Biópsia , Estudos Transversais , Feminino , Variação Genética , Humanos , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Pele/patologia , Sri Lanka , Cicatrização
11.
Acta Microbiol Immunol Hung ; 68(4): 227-234, 2021 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-34806999

RESUMO

Staphylococcus aureus as an opportunistic bacterial pathogen with intrinsic and acquired resistance to many antibiotics is a worldwide problem. The current study was undertaken to evaluate the resistance pattern, and determine the genetic types of multidrug-resistant S. aureus isolated from wound. This cross-sectional study was conducted over the period of two years (from December 2018 to November 2020) at the hospitals affiliated to Shahid Beheshti University of Medical Sciences, Tehran, Iran. In present study, 75 multidrug-resistant S. aureus isolates collected from wound infections were investigated. Phenotypic resistance was assessed by Kirby-Bauer disk diffusion method. Conventional PCR was performed for the detection of virulence encoding genes. Genotyping of strains was performed based on coa gene polymorphism using multiplex-PCR assay. SCCmec typing, spa typing and MLST were also used to characterize the genotype of the mupirocin, tigecycline and vancomycin resistant multidrug-resistant S. aureus isolates. All 75 multidrug-resistant S. aureus isolates in the study were confirmed as MRSA. Coagulase typing distinguished isolates into five genotypic patterns including III (40%), I (24%), IVb (16%), V (10.7%) and type X (9.3%). Resistance to tigecycline was detected in 4% of MDR-MRSA isolates and all belonged to CC8/ST239- SCCmec III/t421 lineage. According to our analysis, one VRSA strain was identified that belonged to coa type V and CC/ST22-SCCmec IV/t790 lineage. Resistance to mupirocin was detected in 9.3% of strains. All 7 mupirocin resistant MDR-MRSA isolates exhibited resistance to mupirocin in high level. Of these, 4 isolates belonged to CC/ST8-SCCmec IV/t008 (57.1%), 2 isolates belonged to CC/ST8-SCCmec IV/t064 (28.6%) and one isolate to CC/ST22-SCCmec IV/t790 (14.3%). Altogether, current survey provides a snapshot of the characteristics of S. aureus strains isolated from patients. Our observations highlighted type III as predominant coa type among multidrug-resistant MDR strains indicating low heterogeneity of these isolates. Our study also indicates the importance of continuous monitoring of the genotypes of MDR-MRSA isolates to prevent nosocomial outbreaks and the spread of MDR isolates.


Assuntos
Farmacorresistência Bacteriana Múltipla , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Ferimentos e Lesões , Humanos , Antibacterianos/farmacologia , Estudos Transversais , Irã (Geográfico)/epidemiologia , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Mupirocina/farmacologia , Infecções Estafilocócicas/epidemiologia , Staphylococcus aureus/genética , Staphylococcus aureus/isolamento & purificação , Tigeciclina , Staphylococcus aureus Resistente à Vancomicina/genética , Staphylococcus aureus Resistente à Vancomicina/isolamento & purificação , Ferimentos e Lesões/microbiologia , Farmacorresistência Bacteriana Múltipla/genética
12.
J Immunol Res ; 2021: 6417658, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34840990

RESUMO

Enterogenous infection is a major cause of death during traumatic hemorrhagic shock (THS). It has been reported that Toll-like receptor 5 (TLR5) plays an integral role in regulating mucosal immunity and intestinal homeostasis of the microbiota. However, the roles played by TLR5 on intestinal barrier maintenance and commensal bacterial translocation post-THS are poorly understood. In this research, we established THS models in wild-type (WT) and Tlr5-/- (genetically deficient in TLR5 expression) mice. We found that THS promoted bacterial translocation, while TLR5 deficiency played a protective role in preventing commensal bacteria dissemination after THS. Furthermore, intestinal microbiota analysis uncovered that TLR5 deficiency enhanced the mucosal biological barrier by decreasing RegIIIγ-mediated bactericidal activity against G+ anaerobic bacteria. We then sorted small intestinal TLR5+ lamina propria dendritic cells (LPDCs) and analyzed TH1 differentiation in the intestinal lamina propria and a coculture system consisting of LPDCs and naïve T cells. Although TLR5 deficiency attenuated the regulation of TH1 polarization by LPDCs, it conferred stability to the cells during THS. Moreover, retinoic acid (RA) released from TLR5+ LPDCs could play a key role in modulating TH1 polarization. We also found that gavage administration of RA alleviated bacterial translocation in THS-treated WT mice. In summary, we documented that TLR5 signaling plays a pivotal role in regulating RegIIIγ-induced killing of G+ anaerobic bacteria, and LPDCs mediated TH1 differentiation via RA. These processes prevent intestinal bacterial translocation and enterogenous infection after THS, suggesting that therapeutically targeting LPDCs or gut microbiota can interfere with bacterial translocation after THS.


Assuntos
Células Dendríticas/imunologia , Intestinos/imunologia , Mucosa/patologia , Choque Hemorrágico/imunologia , Células Th1/imunologia , Receptor 5 Toll-Like/genética , Ferimentos e Lesões/imunologia , Animais , Diferenciação Celular , Humanos , Imunidade nas Mucosas , Intestinos/microbiologia , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Choque Hemorrágico/microbiologia , Simbiose , Tretinoína/metabolismo , Ferimentos e Lesões/microbiologia
13.
Emerg Microbes Infect ; 10(1): 2326-2339, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34821529

RESUMO

ABSTRACTMelioidosis is a serious infectious disease endemic in Southeast Asia, Northern Australia and has been increasingly reported in other tropical and subtropical regions in the world. Percutaneous inoculation through cuts and wounds on the skin is one of the major modes of natural transmission. Despite cuts in skin being a major route of entry, very little is known about how the causative bacterium Burkholderia pseudomallei initiates an infection at the skin and the disease manifestation at the skin known as cutaneous melioidosis. One key issue is the lack of suitable and relevant infection models. Employing an in vitro 2D keratinocyte cell culture, a 3D skin equivalent fibroblast-keratinocyte co-culture and ex vivo organ culture from human skin, we developed infection models utilizing surrogate model organism Burkholderia thailandensis to investigate Burkholderia-skin interactions. Collectively, these models show that the bacterial infection was largely limited at the wound's edge. Infection impedes wound closure, triggers inflammasome activation and cellular extrusion in the keratinocytes as a potential way to control bacterial infectious load at the skin. However, extensive infection over time could result in the epidermal layer being sloughed off, potentially contributing to formation of skin lesions.


Assuntos
Burkholderia pseudomallei/fisiologia , Burkholderia/fisiologia , Epiderme/microbiologia , Inflamassomos/metabolismo , Queratinócitos/microbiologia , Melioidose/microbiologia , Pele/microbiologia , Ferimentos e Lesões/microbiologia , Células Cultivadas , Epiderme/metabolismo , Humanos , Queratinócitos/metabolismo , Melioidose/metabolismo , Melioidose/patologia , Modelos Biológicos , Pele/metabolismo , Pele/patologia , Ferimentos e Lesões/metabolismo , Ferimentos e Lesões/patologia
14.
Cell Mol Biol (Noisy-le-grand) ; 67(1): 96-100, 2021 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-34817362

RESUMO

The skin is the largest organ in the human body, and due to its barrier function, it is susceptible to multiple injuries. The appearance of infections during the wound healing process is a complication that represents a formidable hospital challenge. The presence of opportunistic bacteria with sophisticated resistance mechanisms is difficult to eradicate and compromises patients' lives. Therefore, the search for new efficacious treatments from natural sources that prevent and counteract infections, in addition to promoting the healing process, has increased in recent years. In this respect, films with the capability to protect wounds and release drugs are the presentation that predominates commercially in the hospital environment. Those films can offer several mechanical advantages such as physical protection to prevent opportunistic bacteria's entry, regulation of gas exchange, and capture of exudate through a swelling process. Wound dressings are generally curative materials easily adaptable to different anatomical regions, with high strength and elasticity, and some are even bioabsorbable. Additionally, the components of the films can actively participate in promoting the healing process. Even more, the film can be made up of carriers with other active participants to prevent and eradicate infections. Therefore, the extensive versatility, practicality, and usefulness of films from natural sources to address infectious processes during wound healing are relevant and recurrent themes. This work presents an analysis of the state-of-the-art of films with natural products focused on preventing and eradicating infections in wound healing.


Assuntos
Produtos Biológicos/farmacologia , Infecções Oportunistas/prevenção & controle , Cicatrização/efeitos dos fármacos , Infecção dos Ferimentos/prevenção & controle , Ferimentos e Lesões/prevenção & controle , Produtos Biológicos/química , Humanos , Hidrogéis/química , Hidrogéis/farmacologia , Membranas Artificiais , Infecções Oportunistas/microbiologia , Plastificantes/química , Plastificantes/farmacologia , Substâncias Protetoras/química , Substâncias Protetoras/farmacologia , Infecção dos Ferimentos/microbiologia , Ferimentos e Lesões/microbiologia
15.
PLoS Negl Trop Dis ; 15(10): e0009862, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34644298

RESUMO

BACKGROUND: Chronic wounds pose a significant healthcare burden in low- and middle-income countries. Buruli ulcer (BU), caused by Mycobacterium ulcerans infection, causes wounds with high morbidity and financial burden. Although highly endemic in West and Central Africa, the presence of BU in Sierra Leone is not well described. This study aimed to confirm or exclude BU in suspected cases of chronic wounds presenting to Masanga Hospital, Sierra Leone. METHODOLOGY: Demographics, baseline clinical data, and quality of life scores were collected from patients with wounds suspected to be BU. Wound tissue samples were acquired and transported to the Swiss Tropical and Public Health Institute, Switzerland, for analysis to detect Mycobacterium ulcerans using qPCR, microscopic smear examination, and histopathology, as per World Health Organization (WHO) recommendations. FINDINGS: Twenty-one participants with wounds suspected to be BU were enrolled over 4-weeks (Feb-March 2019). Participants were predominantly young working males (62% male, 38% female, mean 35yrs, 90% employed in an occupation or as a student) with large, single, ulcerating wounds (mean diameter 9.4cm, 86% single wound) exclusively of the lower limbs (60% foot, 40% lower leg) present for a mean 15 months. The majority reported frequent exposure to water outdoors (76%). Self-reports of over-the-counter antibiotic use prior to presentation was high (81%), as was history of trauma (38%) and surgical interventions prior to enrolment (48%). Regarding laboratory investigation, all samples were negative for BU by microscopy, histopathology, and qPCR. Histopathology analysis revealed heavy bacterial load in many of the samples. The study had excellent participant recruitment, however follow-up proved difficult. CONCLUSIONS: BU was not confirmed as a cause of chronic ulceration in our cohort of suspected cases, as judged by laboratory analysis according to WHO standards. This does not exclude the presence of BU in the region, and the definitive cause of these treatment-resistance chronic wounds is uncertain.


Assuntos
Úlcera de Buruli/microbiologia , Mycobacterium ulcerans/isolamento & purificação , Doenças Negligenciadas/microbiologia , Ferimentos e Lesões/microbiologia , Adolescente , Adulto , Idoso , Antibacterianos/uso terapêutico , Úlcera de Buruli/tratamento farmacológico , Úlcera de Buruli/epidemiologia , Doença Crônica/epidemiologia , Estudos de Coortes , Feminino , Hospitais/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Mycobacterium ulcerans/efeitos dos fármacos , Mycobacterium ulcerans/genética , Mycobacterium ulcerans/fisiologia , Doenças Negligenciadas/tratamento farmacológico , Doenças Negligenciadas/epidemiologia , Serra Leoa/epidemiologia , Ferimentos e Lesões/epidemiologia , Adulto Jovem
16.
Nursing (Ed. bras., Impr.) ; 24(281): 6347-6354, out.-2021.
Artigo em Inglês, Português | LILACS, BDENF - Enfermagem | ID: biblio-1344576

RESUMO

Objetivo: Construir e obter a evidência de validade de conteúdo da Escala de Avaliação do Odor de Feridas Neoplásicas. Método: Estudo conduzido em 2019 em duas etapas: construção da escala a partir de revisão de literatura e validação a partir da avaliação de 17 juízes que responderam a um questionário por meio de ferramenta online. Foi aplicado o cálculo de índice de Validade de Conteúdo (IVC) para a análise dos dados. Resultados: As principais mudanças indicadas foram: retirada do swab para avaliar a carga microbiana e a inclusão do exsudato sanguinolento como item relevante na avaliação do odor. O IVC da escala foi de 0,91, indicando que 91% dos juízes consideraram a escala um instrumento relevante para avaliar o odor das feridas neoplásicas. Conclusão: A escala desenvolvida foi aprovada como instrumento de análise clínica que poderá auxiliar os profissionais na avaliação mais consistente do odor das feridas neoplásicas.(AU)


Objective: To build and obtain evidence of content validity of the Neoplastic Wound Odor Rating Scale. Materials and method: Two-step study: construction of the scale based on a literature review and validation based on the evaluation of 17 judges who answered a questionnaire through an online tool. The Content Validity Index (CVI) calculation was applied for data analysis. Results: The main changes indicated were: removal of the swab to assess the microbial load and the inclusion of bloody exudate as a relevant item in the odor assessment. The scale's CVI was 0.91, indicating that 91% of the judges considered the scale a relevant instrument to assess the odor of neoplastic wounds. Conclusion: The developed scale was approved as a clinical analysis instrument that can help professionals to more consistently assess the odor of neoplastic wounds.(AU)


Objetivo: Construir y obtener evidencia de la validez de contenido de la Escala de calificación de olores de heridas neoplásicas. Materiales y método: Estudio de dos pasos: construcción de la escala a partir de una revisión de la literatura y validación a partir de la evaluación de 17 jueces que respondieron un cuestionario a través de una herramienta online. Se aplicó el cálculo del Índice de Validez de Contenido (IVC) para el análisis de datos. Resultados: Los principales cambios indicados fueron: extracción del hisopo para evaluar la carga microbiana y la inclusión de exudado sanguinolento como elemento relevante en la evaluación de olores. El CVI de la escala fue de 0,91, lo que indica que el 91% de los jueces consideró la escala un instrumento relevante para evaluar el olor de las heridas neoplásicas. Conclusión: La escala desarrollada fue aprobada como un instrumento de análisis clínico que puede ayudar a los profesionales a evaluar de manera más consistente el olor de las heridas neoplásicas.(AU)


Assuntos
Humanos , Neoplasias Cutâneas , Ferimentos e Lesões/microbiologia , Odorantes/análise
17.
Int J Biol Macromol ; 188: 811-819, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34390748

RESUMO

Designing an antibacterial agent with a suitable water vapor permeability, good mechanical properties, and controlled antibiotic release is a promising method for stopping bacterial infection in wound tissue. In this respect, this work aims to prepare novel flexible polymeric hydrogel films via integrating UiO-66 into the polymeric carboxymethyl cellulose (CMC) hydrogel for improving the mechanical and antibiotic release performances. First, we performed a green hydrothermal synthetic method to synthesis UiO-66 and followed by encapsulating Tetracycline (TC) through immersion in its aqueous solution. Also, the casting technique was utilized to integrate different concentrations of the TC-encapsulated UiO-66 (TC@UiO-66, 5% to 15%) in the polymeric CMC matrix (CMC/TC@UiO-66) cross-linked by citric acid and plasticized by glycerol. The release performance showed a low initial burst release with a controlled release over 72 h in the artificial sweat and simulated wound exudate (PBS, pH 7.4) media. The in vitro cytotoxicity and antibacterial activity results revealed a good cytocompatibility toward Human skin fibroblast (HFF-1) cells and a significant activity against both E. coli and S. aureus with 1.3 and 1.7 cm inhibition zone, respectively. The obtained results recommend CMC/TC@UiO-66 films as a potential antibacterial wound dressing.


Assuntos
Antibacterianos/farmacologia , Bandagens/microbiologia , Carboximetilcelulose Sódica/química , Hidrogéis/química , Nanocompostos/química , Compostos Organometálicos/química , Ácidos Ftálicos/química , Tetraciclina/farmacologia , Ferimentos e Lesões/microbiologia , Morte Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Liberação Controlada de Fármacos , Escherichia coli/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Testes de Sensibilidade Microbiana , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/efeitos dos fármacos , Resistência à Tração
18.
Molecules ; 26(16)2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34443592

RESUMO

The bacterial infection of post-operative wounds is a common health problem. Therefore, it is important to investigate fast and accurate methods of identifying bacteria in clinical samples. The aim of the study was to analyse the use of the MALDI-TOF MS technique to identify microorganism wounds that are difficult to heal. The most common bacteria are Escherichia coli, Staphylococcus spp., and Enterococcus spp. We also demonstrate the effect of culture conditions, such as the used growth medium (solid: Brain Heart Infusion Agar, Mueller Hilton Agar, Glucose Bromocresol Purple Agar, and Vancomycin Resistance Enterococci Agar Base and liquid: Tryptic Soy Broth and BACTEC Lytic/10 Anaerobic/F), the incubation time (4, 6, and 24h), and the method of the preparation of bacterial protein extracts (the standard method based on the Bruker guideline, the Sepsityper method) to identify factors and the quality of the obtained mass spectra. By comparing the protein profiles of bacteria from patients not treated with antibiotics to those treated with antibiotics based on the presence/absence of specific signals and using the UniProt platform, it was possible to predict the probable mechanism of the action of the antibiotic used and the mechanism of drug resistance.


Assuntos
Bactérias/isolamento & purificação , Técnicas Bacteriológicas/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Ferimentos e Lesões/microbiologia , Farmacorresistência Bacteriana , Humanos , Período Pós-Operatório
19.
Int J Biol Macromol ; 186: 656-685, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34271047

RESUMO

Biomaterials are being extensively used in regenerative medicine including tissue engineering applications, as these enhance tissue development, repair, and help in the process of angiogenesis. Wound healing is a crucial biological process of regeneration of ruptured tissue after getting injury to the skin and other soft tissue in humans and animals. Besides, the accumulation of microbial biofilms around the wound surface can increase the risk and physically obstruct the wound healing activity, and may even lead to amputation. Hence, in both acute and chronic wounds, prominent biomaterials are required for wound healing along with antimicrobial agents. This review comprehensively addresses the antimicrobial and wound healing effects of chitosan, chitin, cellulose acetate, hyaluronic acid, pullulan, bacterial cellulose, fibrin, alginate, etc. based wound dressing biomaterials fabricated with natural resources such as honey, plant bioactive compounds, and marine-based polymers. Due to their excellent biocompatibility and biodegradability, bioactive compounds derived from honey, plants, and marine resources are commonly used in biomedical and tissue engineering applications. Different types of polymer-based biomaterials including hydrogel, film, scaffold, nanofiber, and sponge dressings fabricated with bioactive agents including honey, curcumin, tannin, quercetin, andrographolide, gelatin, carrageenan, etc., can exhibit significant wound healing process in, diabetic wounds, diabetic ulcers, and burns, and help in cartilage repair along with good biocompatibility and antimicrobial effects. Among the reviewed biomaterials, carbohydrate polymers such as chitosan-based biomaterials are prominent and widely used for wound healing applications followed by hyaluronic acid and alginate-based biomaterials loaded with honey, plant, and marine compounds. This review first provides an overview of the vast natural resources used to formulate different biomaterials for the treatment of antimicrobial, acute, and chronic wound healing processes.


Assuntos
Anti-Infecciosos/farmacologia , Organismos Aquáticos , Bandagens , Mel , Extratos Vegetais/farmacologia , Polímeros/farmacologia , Pele/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Ferimentos e Lesões/tratamento farmacológico , Alginatos/isolamento & purificação , Alginatos/farmacologia , Animais , Anti-Infecciosos/isolamento & purificação , Organismos Aquáticos/química , Quitosana/isolamento & purificação , Quitosana/farmacologia , Portadores de Fármacos , Composição de Medicamentos , Humanos , Ácido Hialurônico/isolamento & purificação , Ácido Hialurônico/farmacologia , Extratos Vegetais/isolamento & purificação , Polímeros/isolamento & purificação , Pele/lesões , Pele/microbiologia , Pele/patologia , Ferimentos e Lesões/microbiologia , Ferimentos e Lesões/patologia
20.
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
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