RESUMO
Erythromycin fermentation residue (EFR) represents a typical hazardous waste produced by the microbial pharmaceutical industry. Although electrolysis is promising for EFR disposal, its microbial threats remain unclear. Herein, metagenomics was coupled with the random forest technique to decipher the antibiotic resistance patterns of electrochemically treated EFR. Results showed that 95.75% of erythromycin could be removed in 2 hr. Electrolysis temporarily influenced EFR microbiota, where the relative abundances of Proteobacteria and Actinobacteria increased, while those of Fusobacteria, Firmicutes, and Bacteroidetes decreased. A total of 505 antibiotic resistance gene (ARG) subtypes encoding resistance to 21 antibiotic types and 150 mobile genetic elements (MGEs), mainly including plasmid (72) and transposase (52) were assembled in EFR. Significant linear regression models were identified among microbial richness, ARG subtypes, and MGE numbers (r2=0.50-0.81, p< 0.001). Physicochemical factors of EFR (Total nitrogen, total organic carbon, protein, and humus) regulated ARG and MGE assembly (%IncMSE value = 5.14-14.85). The core ARG, MGE, and microbe sets (93.08%-99.85%) successfully explained 89.71%-92.92% of total ARG and MGE abundances. Specifically, gene aph(3')-I, transposase tnpA, and Mycolicibacterium were the primary drivers of the resistance dissemination system. This study also proposes efficient resistance mitigation measures, and provides recommendations for future management of antibiotic fermentation residue.
Assuntos
Eritromicina , Fermentação , Metagenômica , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos/genética , Farmacorresistência Bacteriana/genéticaRESUMO
Complex tissue damage accompanying with bacterial infection challenges healthcare systems globally. Conventional tissue engineering scaffolds normally generate secondary implantation trauma, mismatched regeneration and infection risks. Herein, we developed an easily implanted scaffold with multistep shape memory and photothermal-chemodynamic properties to exactly match repair requirements of each part from the tissue defect by adjusting its morphology as needed meanwhile inhibiting bacterial infection on demand. Specifically, a thermal-induced shape memory scaffold was prepared using hydroxyethyl methacrylate and polyethylene glycol diacrylate, which was further combined with the photothermal agent iron tannate (FeTA) to produce NIR light-induced shape memory property. By varying ingredients ratios in each segment, this scaffold could perform a stepwise recovery under different NIR periods. This process facilitated implantation after shape fixing to avoid trauma caused by conventional methods and gradually filled irregular defects under NIR to perform suitable tissue regeneration. Moreover, FeTA also catalyzed Fenton reaction at bacterial infections with abundant H2O2, which produced excess ROS for chemodynamic antibacterial therapy. As expected, bacteriostatic rate was further enhanced by additional photothermal therapy under NIR. The in vitro and vivo results showed that our scaffold was able to perform high efficacy in both antibiosis, inflammation reduction and wound healing acceleration, indicating a promising candidate for the regeneration of complex tissue damage with bacterial infection.
Assuntos
Antibacterianos , Alicerces Teciduais , Cicatrização , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/uso terapêutico , Animais , Alicerces Teciduais/química , Camundongos , Cicatrização/efeitos dos fármacos , Raios Infravermelhos , Terapia Fototérmica , Engenharia Tecidual/métodos , Taninos/química , Taninos/farmacologia , Materiais Inteligentes/química , Staphylococcus aureus/efeitos dos fármacos , Masculino , Polietilenoglicóis/químicaRESUMO
Biofilm-associated infections (BAIs) continue to pose a major challenge in the medical field. Nanomedicine, in particular, promises significant advances in combating BAIs through the introduction of a variety of nanomaterials and nano-antimicrobial strategies. However, studies to date have primarily focused on the removal of the bacterial biofilm and neglect the subsequent post-biofilm therapeutic measures for BAIs, rendering pure anti-biofilm strategies insufficient for the holistic recovery of affected patients. Herein, we construct an emerging dual-functional composite nanosheet (SiHx@Ga) that responds to pHs fluctuation in the biofilm microenvironment to enable a sequential therapy of BAIs. In the acidic environment of biofilm, SiHx@Ga employs the self-sensitized photothermal Trojan horse strategy to effectively impair the reactive oxygen species (ROS) defense system while triggering oxidative stress and lipid peroxidation of bacteria, engendering potent antibacterial and anti-biofilm effects. Surprisingly, in the post-treatment phase, SiHx@Ga adsorbs free pathogenic nucleic acids released after biofilm destruction, generates hydrogen with ROS-scavenging and promotes macrophage polarization to the M2 type, effectively mitigating damaging inflammatory burst and promoting tissue healing. This well-orchestrated strategy provides a sequential therapy of BAIs by utilizing microenvironmental variations, offering a conceptual paradigm shift in the field of nanomedicine anti-infectives.
Assuntos
Antibacterianos , Biofilmes , Gálio , Espécies Reativas de Oxigênio , Biofilmes/efeitos dos fármacos , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo , Gálio/química , Gálio/farmacologia , Camundongos , Portadores de Fármacos/química , Células RAW 264.7 , Humanos , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/fisiologiaRESUMO
Although MALDI-TOF mass spectrometry (MS) is considered as the gold standard for rapid and cost-effective identification of microorganisms in routine laboratory practices, its capability for antimicrobial resistance (AMR) detection has received limited focus. Nevertheless, recent studies explored the predictive performance of MALDI-TOF MS for detecting AMR in clinical pathogens when machine learning techniques are applied. This chapter describes a routine MALDI-TOF MS workflow for the rapid screening of AMR in foodborne pathogens, with Campylobacter spp. as a study model.
Assuntos
Campylobacter , Farmacorresistência Bacteriana , Aprendizado de Máquina , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Campylobacter/efeitos dos fármacos , Antibacterianos/farmacologia , Humanos , Microbiologia de Alimentos/métodos , Testes de Sensibilidade Microbiana/métodos , Doenças Transmitidas por Alimentos/microbiologia , Bactérias/efeitos dos fármacosRESUMO
Unveiling the strategies of bacterial adaptation to stress constitute a challenging area of research. The understanding of mechanisms governing emergence of resistance to antimicrobials is of particular importance regarding the increasing threat of antibiotic resistance on public health worldwide. In the last decades, the fast democratization of sequencing technologies along with the development of dedicated bioinformatical tools to process data offered new opportunities to characterize genomic variations underlying bacterial adaptation. Thereby, research teams have now the possibility to dive deeper in the deciphering of bacterial adaptive mechanisms through the identification of specific genetic targets mediating survival to stress. In this chapter, we proposed a step-by-step bioinformatical pipeline enabling the identification of mutational events underlying biocidal stress adaptation associated with antimicrobial resistance development using Escherichia marmotae as an illustrative model.
Assuntos
Biologia Computacional , Genoma Bacteriano , Genômica , Mutação , Genômica/métodos , Biologia Computacional/métodos , Bactérias/genética , Bactérias/efeitos dos fármacos , Farmacorresistência Bacteriana/genética , Antibacterianos/farmacologia , Software , Sequenciamento de Nucleotídeos em Larga Escala/métodosRESUMO
Shewanella baltica is a specific spoilage organism of golden pomfret. This study aims to explore the antibacterial mechanism of slightly acidic electrolysed water (SAEW) against S. baltica (strains ABa4, ABe2 and BBe1) in golden pomfret broths by metabolomics, proteomics and bioinformatics analyses. S. baltica was decreased by at least 3.94 log CFU/mL after SAEW treatment, and strain ABa4 had the highest resistance. Under SAEW stress, amino acids and organic acids in S. baltica decreased, and nucleotide related compounds degraded. Furthermore, 100 differentially expressed proteins (DEPs) were identified. Most DEPs of strains ABe2 and BBe1 were down-regulated, while some DEPs of strain ABa4 were up-regulated, especially those oxidative stress related proteins. These results suggest that the modes of SAEW against S. baltica can be traced to the inhibition of amino acid, carbon, nucleotide and sulphur metabolisms, and the loss of functional proteins for temperature regulation, translation, motility and protein folding.
Assuntos
Proteínas de Bactérias , Shewanella , Shewanella/metabolismo , Shewanella/química , Shewanella/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Água/metabolismo , Água/química , Eletrólise , Antibacterianos/farmacologia , Antibacterianos/metabolismo , Antibacterianos/química , Concentração de Íons de Hidrogênio , Vigna/química , Vigna/microbiologia , Vigna/metabolismoRESUMO
Aquatic products are highly susceptible to spoilage, and preparing composite edible film with essential oil is an effective solution. In this study, composite edible films were prepared using perilla essential oil (PEO)-glycerol monolaurate emulsions incorporated with chitosan and nisin, and the film formulation was optimized by response surface methodology. These films were applied to ready-to-eat fish balls and evaluated over a period of 12 days. The films with the highest inhibition rate against Staphylococcus aureus were acquired using a polymer composition of 6 µL/mL PEO, 18.4 µg/mL glycerol monolaurate, 14.2 mg/mL chitosan, and 11.0 µg/mL nisin. The fish balls coated with the optimal edible film showed minimal changes in appearance during storage and significantly reduced total bacterial counts and total volatile basic nitrogen compared to the control groups. This work indicated that the composite edible films containing essential oils possess ideal properties as antimicrobial packaging materials for aquatic foods.
Assuntos
Antibacterianos , Quitosana , Filmes Comestíveis , Emulsões , Embalagem de Alimentos , Lauratos , Monoglicerídeos , Nisina , Óleos Voláteis , Staphylococcus aureus , Nisina/farmacologia , Nisina/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Lauratos/química , Lauratos/farmacologia , Embalagem de Alimentos/instrumentação , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Emulsões/química , Quitosana/química , Quitosana/farmacologia , Monoglicerídeos/química , Monoglicerídeos/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Óleos de Plantas/química , Óleos de Plantas/farmacologia , Perilla/químicaRESUMO
Chlorogenic acid (CGA) is a well-known plant secondary metabolite exhibiting multiple physiological functions. The present study focused on screening for synergistic antibacterial combinations containing CGA. The combination of CGA and p-coumaric acid (pCA) exhibited remarkably enhanced antibacterial activity compared to that when administering the treatment only. Scanning electron microscopy revealed that a low-dose combination treatment could disrupt the Shigella dysenteriae cell membrane. A comprehensive analysis using nucleic acid and protein leakage assay, conductivity measurements, and biofilm formation inhibition experiments revealed that co-treatment increased the cell permeability and inhibited the biofilm formation substantially. Further, the polyacrylamide protein- and agarose gel-electrophoresis indicated that the proteins and DNA genome of Shigella dysenteriae severely degraded. Finally, the synergistic bactericidal effect was established for fresh-cut tomato preservation. This study demonstrates the remarkable potential of strategically selecting antibacterial agents with maximum synergistic effect and minimum dosage exhibiting excellent antibacterial activity in food preservation.
Assuntos
Antibacterianos , Ácido Clorogênico , Ácidos Cumáricos , Sinergismo Farmacológico , Shigella dysenteriae , Antibacterianos/farmacologia , Antibacterianos/química , Ácidos Cumáricos/farmacologia , Ácidos Cumáricos/química , Ácido Clorogênico/farmacologia , Ácido Clorogênico/química , Shigella dysenteriae/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Biofilmes/efeitos dos fármacos , Propionatos/farmacologia , Solanum lycopersicum/química , Solanum lycopersicum/microbiologia , Conservação de Alimentos/métodosRESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: Mouthwashes based on medicinal plants have demonstrated benefits in controlling plaque and inflammation, acting positively on the oral hygiene of patients with gingivitis. In traditional medicine, Punica granatum L. has been used to treat oral diseases in countries in Europe, Asia, North America, and Africa. AIM OF THE STUDY: The present study aimed to conduct a comprehensive review on the dental applications of Punica granatum L. for the treatment of gingivitis, including ethnomedicinal uses, analysis of randomized clinical trials, antibacterial activity against Porphyromonas gingivalis, mechanisms of action of phytochemicals isolated from this plant, and preclinical toxicity. MATERIALS AND METHODS: The literature was retrieved from Google Scholar, PubMed®, SciELO, and ScienceDirect®, since the first report published on the topic in 2001 until March 2024. RESULTS: Several clinical trials have demonstrated that mouthwashes containing P. granatum have equal or better efficacy than chlorhexidine in treating patients with gingivitis, confirming the indications for use of this plant by traditional communities. However, reports on the in vitro antibacterial activity of extracts from the fruits of this plant have not shown clinical relevance against the pathogen P. gingivalis. The ellagitannin punicalagin isolated from P. granatum has shown potential against several strains of Gram-positive and Gram-negative bacteria, but, to date, this compound has not yet been tested against P. gingivalis. It is likely that the mechanisms of action of flavonoids, such as quercetin, are involved in the inhibition of the activities of the RgpA, RgpB, and Kgp proteases of P. gingivalis. CONCLUSIONS: In summary, natural products obtained from P. granatum do not present toxic side effects and can be considered as possible substitutes of commercial products recommended for the treatment of gingivitis and other oral diseases.
Assuntos
Antibacterianos , Gengivite , Extratos Vegetais , Porphyromonas gingivalis , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Gengivite/tratamento farmacológico , Porphyromonas gingivalis/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Punica granatum/química , Medicina Tradicional , Animais , FitoterapiaRESUMO
Osteomyelitis is an osseous infectious disease that primarily affects children and the elderly with high morbidity and recurrence. The conventional treatments of osteomyelitis contain long-term and high-dose systemic antibiotics with debridements, which are not effective and lead to antibiotic resistance with serious side/adverse effects in many cases. Hence, developing novel antibiotic-free interventions against osteomyelitis (especially antibiotic-resistant bacterial infection) is urgent and anticipated. Here, a bone mesenchymal stem cell membrane-constructed nanocell (CFE@CM) was fabricated against osteomyelitis with the characteristics of acid-responsiveness, hydrogen peroxide self-supplying, enhanced chemodynamic therapeutic efficacy, bone marrow targeting and cuproptosis induction. Notably, mRNA sequencing was applied to unveil the underlying biological mechanisms and found that the biological processes related to copper ion binding, oxidative phosphorylation, peptide biosynthesis and metabolism, etc., were disturbed by CFE@CM in bacteria. This work provided an innovative antibiotic-free strategy against osteomyelitis through copper-enhanced Fenton reaction and distinct cuproptosis, promising to complement the current insufficient therapeutic regimen in clinic.
Assuntos
Cobre , Osteomielite , Osteomielite/tratamento farmacológico , Animais , Cobre/química , Cobre/farmacologia , Concentração de Íons de Hidrogênio , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/citologia , Camundongos , Peróxido de Hidrogênio/metabolismo , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Antibacterianos/química , Humanos , Staphylococcus aureus/efeitos dos fármacosRESUMO
Implant-associated infection (IAI) has become an intractable challenge in clinic. The healing of IAI is a complex physiological process involving a series of spatiotemporal connected events. However, existing titanium-based implants in clinic suffer from poor antibacterial effect and single function. Herein, a versatile surface platform based on the presentation of sequential function is developed. Fabrication of titania nanotubes and poly-γ-glutamic acid (γ-PGA) achieves the efficient incorporation of silver ions (Ag+) and the pH-sensitive release in response to acidic bone infection microenvironment. The optimized PGA/Ag platform exhibits satisfactory biocompatibility and converts macrophages from pro-inflammatory M1 to pro-healing M2 phenotype during the subsequent healing stage, which creates a beneficial osteoimmune microenvironment and promotes angio/osteogenesis. Furthermore, the PGA/Ag platform mediates osteoblast/osteoclast coupling through inhibiting CCL3/CCR1 signaling. These biological effects synergistically improve osseointegration under bacterial infection in vivo, matching the healing process of IAI. Overall, the novel integrated PGA/Ag surface platform proposed in this study fulfills function cascades under pathological state and shows great potential in IAI therapy.
Assuntos
Antibacterianos , Ácido Poliglutâmico , Prata , Titânio , Animais , Titânio/química , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Camundongos , Ácido Poliglutâmico/química , Ácido Poliglutâmico/análogos & derivados , Prata/química , Prata/farmacologia , Propriedades de Superfície , Nanotubos/química , Células RAW 264.7 , Infecções Relacionadas à Prótese/tratamento farmacológico , Osseointegração/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Osteoblastos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Cicatrização/efeitos dos fármacos , Próteses e ImplantesRESUMO
Osteomyelitis (OM) is a progressive, inflammatory infection of bone caused predominately by Staphylococcus aureus. Herein, we engineered an antibiotic-eluting collagen-hydroxyapatite scaffold capable of eliminating infection and facilitating bone healing. An iterative freeze-drying and chemical crosslinking approach was leveraged to modify antibiotic release kinetics, resulting in a layered dual-release system whereby an initial rapid release of antibiotic to clear infection was followed by a sustained controlled release to prevent reoccurrence of infection. We observed that the presence of microbial collagenase accelerated antibiotic release from the crosslinked layer of the scaffold, indicating that the material is responsive to microbial activity. As exemplar drugs, vancomycin and gentamicin-eluting scaffolds were demonstrated to be bactericidal, and supported osteogenesis in vitro. In a pilot murine model of OM, vancomycin-eluting scaffolds were observed to reduce S. aureus infection within the tibia. Finally, in a rabbit model of chronic OM, gentamicin-eluting scaffolds both facilitated radial bone defect healing and eliminated S. aureus infection. These results show that antibiotic-eluting collagen-hydroxyapatite scaffolds are a one-stage therapy for OM, which when implanted into infected bone defects simultaneously eradicate infection and facilitate bone tissue healing.
Assuntos
Antibacterianos , Gentamicinas , Osteomielite , Infecções Estafilocócicas , Staphylococcus aureus , Alicerces Teciduais , Animais , Alicerces Teciduais/química , Antibacterianos/farmacologia , Antibacterianos/química , Infecções Estafilocócicas/tratamento farmacológico , Osteomielite/tratamento farmacológico , Coelhos , Staphylococcus aureus/efeitos dos fármacos , Gentamicinas/farmacologia , Gentamicinas/administração & dosagem , Gentamicinas/química , Gentamicinas/uso terapêutico , Camundongos , Vancomicina/farmacologia , Vancomicina/química , Vancomicina/administração & dosagem , Durapatita/química , Cinética , Cicatrização/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Colágeno/química , FemininoRESUMO
As an emerging environmental contaminant, antibiotic resistance genes (ARGs) in tap water have attracted great attention. Although studies have provided ARG profiles in tap water, research on their abundance levels, composition characteristics, and potential threat is still insufficient. Here, 9 household tap water samples were collected from the Guangdong-Hong Kong-Macao Greater Bay Area (GBA) in China. Additionally, 75 sets of environmental sample data (9 types) were downloaded from the public database. Metagenomics was then performed to explore the differences in the abundance and composition of ARGs. 221 ARG subtypes consisting of 17 types were detected in tap water. Although the ARG abundance in tap water was not significantly different from that found in drinking water plants and reservoirs, their composition varied. In tap water samples, the three most abundant classes of resistance genes were multidrug, fosfomycin and MLS (macrolide-lincosamide-streptogramin) ARGs, and their corresponding subtypes ompR, fosX and macB were also the most abundant ARG subtypes. Regarding the potential mobility, vanS had the highest abundance on plasmids and viruses, but the absence of key genes rendered resistance to vancomycin ineffective. Generally, the majority of ARGs present in tap water were those that have not been assessed and are currently not listed as high-threat level ARG families based on the World Health Organization Guideline. Although the current potential threat to human health posed by ARGs in tap water is limited, with persistent transfer and accumulation, especially in pathogens, the potential danger to human health posed by ARGs should not be ignored.
Assuntos
Água Potável , Resistência Microbiana a Medicamentos , Metagenômica , Resistência Microbiana a Medicamentos/genética , Água Potável/microbiologia , China , Monitoramento Ambiental , Antibacterianos/farmacologia , Microbiologia da ÁguaRESUMO
This paper presents the surface treatment results of titanium, veterinary bone wedges. The functional coating is composed of a porous oxide layer (formed by a plasma electrolytic oxidation process) and a polymer poly(sebacic anhydride) (PSBA) layer loaded with amoxicillin (formed by dip coatings). The coatings were porous and composed of Ca (4.16%-6.54%) and P (7.64%-9.89% determined by scanning electron microscopy with EDX) in the upper part of the implant. The titanium bone wedges were hydrophilic (54° water contact angle) and rough (surface area (Sa):1.16 µm) The surface tension determined using diiodomethane was 68.6 ± 2.0° for the anodized implant and was similar for hybrid coatings: 60.7 ± 2.2°. 12.87 ± 0.91 µg/mL of amoxicillin was released from the implants during the first 30 min after immersion in the phosphate-buffered saline (PBS) solution. This concentration was enough to inhibit the Staphylococcus aureus ATCC 25923, and Staphylococcus epidermidis ATCC12228 growth. The obtained inhibition zones were between 27.3 ± 2.1 mm-30.7 ± 0.6 mm when implant extract after 1 h or 4 h immersion in PBS was collected. Various implant biocompatibility analyses were performed under in vivo conditions, including pyrogen test (3 rabbits), intracutaneous reactivity (3 rabbits, 5 places by side), acute systemic toxicity (20 house mice), and local lymph node assay (LLNA) (20 house mice). The extracts from implants were collected in polar and non-polar solutions, and the tests were conducted according to ISO 10993 standards. The results from the in vivo tests showed, that the implant's extracts are not toxic (mass body change below 5%), not sensitizing (SI < 1.6), and do not show the pyrogen effect (changes in the temperature 0.15ºC). The biocompatibility tests were performed in a certificated laboratory with a good laboratory practice certificate after all the necessary permissions.
Assuntos
Amoxicilina , Antibacterianos , Cerâmica , Materiais Revestidos Biocompatíveis , Teste de Materiais , Polímeros , Staphylococcus aureus , Staphylococcus epidermidis , Titânio , Titânio/química , Titânio/farmacologia , Antibacterianos/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Materiais Revestidos Biocompatíveis/química , Animais , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus epidermidis/efeitos dos fármacos , Teste de Materiais/métodos , Cerâmica/química , Cerâmica/farmacologia , Polímeros/química , Polímeros/farmacologia , Amoxicilina/farmacologia , Camundongos , Propriedades de Superfície , Próteses e Implantes , Osso e Ossos/efeitos dos fármacos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologiaRESUMO
The negative membrane potential within bacterial cells is crucial in various essential cellular processes. Sustaining a hyperpolarised membrane could offer a novel strategy to combat antimicrobial resistance. However, it remains uncertain which molecules are responsible for inducing hyperpolarization and what the underlying molecular mechanisms are. Here, we demonstrate that chemically diverse antimicrobial peptides (AMPs) trigger hyperpolarization of the bacterial cytosolic membrane when applied at subinhibitory concentrations. Specifically, these AMPs adopt a membrane-induced amphipathic structure and, thereby, generate hyperpolarization in Escherichia coli without damaging the cell membrane. These AMPs act as selective ionophores for K+ (over Na+) or Cl- (over H2PO4- and NO3-) ions, generating diffusion potential across the membrane. At lower dosages of AMPs, a quasi-steady-state membrane polarisation value is achieved. Our findings highlight the potential of AMPs as a valuable tool for chemically hyperpolarising bacteria, with implications for antimicrobial research and bacterial electrophysiology.
Assuntos
Peptídeos Antimicrobianos , Membrana Celular , Escherichia coli , Potenciais da Membrana , Escherichia coli/efeitos dos fármacos , Potenciais da Membrana/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Peptídeos Antimicrobianos/farmacologia , Peptídeos Antimicrobianos/química , Antibacterianos/farmacologia , Antibacterianos/química , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/químicaRESUMO
BACKGROUND: Bacillus strains are well recognized for their inherent production of bioactive compounds that exhibit antibacterial and anticancer properties. This study aims to evaluate the antimicrobial and anticancer effects of the secondary metabolite isolated from Bacillus licheniformis and Bacillus siamensis strain. MATERIAL AND METHOD: We developed and purified a new soil-derived Bacillus strain to study its metabolites on cancer cells and bacteria. After evaluating the antimicrobial effects of the selected strains' secondary metabolites by well diffusion, growth conditions and temperature optimised using liquid-liquid extraction, secondary metabolites isolated, and active compounds identified using GC-MS. Evaluation of PC-3 and HPrEpC cytotoxicity. AV/PI staining and comet assay assessed necrosis and apoptosis. Real-time PCR measured apoptotic gene expression. Finally, the scratch test measured cell movement. RESULTS: Bacillus strain metabolites exhibit dual-purpose antimicrobial and anticancer properties. Bacillus licheniformis isolate 56 and S2-G12 isolate 60 demonstrated the greatest antibacterial activity. Among all Bacillus isolates, isolates 56 (Bacillus licheniformis) and 60 (Bacillus siamensis strain) had the highest antibacterial activity. Crude extracts obtained from strains 56 and 60 decreased PC-3 cell viability in a dose-dependent manner. At 200 µg/mL, the survival rate of cells treated with strain 56 and 60 crude extract was 23% and 25%, respectively (p < 0.001). The treatment of PC-3 cells with strains 56 and 60 crude extract led to considerable apoptosis (46.2% and 50.09%, respectively) compared to the control group. After treatment with the crude extract from strains 56 and 60 at an IC50 concentration, a significant number of PC-3 cells showed comet formation, indicating DNA fragmentation. Metabolites extracted from strain 56 and 60 enhanced caspase 3, caspase 8, and Bax genes expression and reduced Bcl-2 expression (p < 0.001). Cell migration was also prevented. CONCLUSION: Our findings show that the secondary metabolites of B. licheniformis and B. siamensis have antibiotic and anticancer properties. However in vivo studies are necessary to confirm these findings.
Assuntos
Antibacterianos , Antineoplásicos , Apoptose , Bacillus licheniformis , Bacillus , Microbiologia do Solo , Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Bacillus licheniformis/metabolismo , Humanos , Bacillus/metabolismo , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Metabolismo Secundário , Testes de Sensibilidade Microbiana , Sobrevivência Celular/efeitos dos fármacosRESUMO
BACKGROUND AND OBJECTIVES: Nosocomial infections, including drug-resistant Acinetobacter baumannii infections, continue to impact the health of hospitalized patients. This study sought to determine the prevalence of these infections and assess the associated risk factors and clinical outcomes in Gorgan, Iran. METHODS: A retrospective cross-sectional study was conducted on 143 infected patients with Acinetobacter baumannii in two educational hospitals in Gorgan city, Iran between 2016 and 2018. Patient information including age, gender, reason and duration of hospitalization, background of diseases, type of sample culture, symptoms, laboratory findings, prescribed antibiotics, and antibiogram were collected and analyzed. The Logistic regression and survival statistical methods were used by software of SPSS 26. RESULTS: A total of 37 patients (25.87%) died during hospitalization. The less than one year and 45-65 years age groups demonstrated more deaths (29.7%; p-value < 0.001). Being single (not being married) was found to be a risk factor in increasing the chance of death among patients (OR = 2.154, 95% CI: 1.02-4.53; p = 0.048). Hospitalization in intensive care units (ICUs) was a risk factor for the death of patients (OR = 4.655, 95% CI: 7.6-83.2). The resistance to carbapenems was reported to be an important risk factor for the death of patients. CONCLUSIONS: Acinetobacter baumannii infections, particularly those resistant to carbapenems, are a significant risk for patients in ICUs and can lead to higher mortality rates.
Assuntos
Infecções por Acinetobacter , Acinetobacter baumannii , Antibacterianos , Carbapenêmicos , Infecção Hospitalar , Humanos , Acinetobacter baumannii/efeitos dos fármacos , Masculino , Feminino , Irã (Geográfico)/epidemiologia , Pessoa de Meia-Idade , Infecções por Acinetobacter/tratamento farmacológico , Infecções por Acinetobacter/mortalidade , Infecções por Acinetobacter/epidemiologia , Infecções por Acinetobacter/microbiologia , Carbapenêmicos/farmacologia , Carbapenêmicos/uso terapêutico , Idoso , Estudos Retrospectivos , Infecção Hospitalar/microbiologia , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/mortalidade , Estudos Transversais , Adulto , Fatores de Risco , Antibacterianos/uso terapêutico , Antibacterianos/farmacologia , Adolescente , Criança , Adulto Jovem , Pré-Escolar , Lactente , Testes de Sensibilidade Microbiana , Farmacorresistência Bacteriana Múltipla , Idoso de 80 Anos ou mais , Prevalência , Unidades de Terapia Intensiva/estatística & dados numéricosRESUMO
BACKGROUND: Scabies disproportionately affects people in resource-poor areas. Clinical diagnosis risks misdiagnosis due to resemblance to other skin diseases, but laboratory confirmation improves accuracy. Scabies allow for secondary bacterial infections. Associated bacteria exacerbate scabies and antibiotic resistance. Ethiopian scabies diagnosis relies solely on clinical exams without confirming parasites or investigating secondary bacterial infections. This study aims to identify parasites via scraping, isolate secondary bacteria, and evaluate their antibiotic susceptibility profiles. METHODS: A hospital based cross-sectional study was conducted from September 2022 to July 2023 among scabies suspected patients who visited the dermatology clinic at Borumeda General Hospital in Northeast Ethiopia. A systematic random sampling technique was used to select 422 study participants. Socio-demographic, hygiene, and clinical characteristics data were collected via face-to-face interviews and observation. Skin scrapings for parasitological investigations and swab samples for microbiological investigations were collected and transported for analysis and drug susceptibility testing. Descriptive statistics and logistic regression analysis were employed to assess risk factors. RESULT: Among 422 skin scraping samples, 156 (37.0%) cases of scabies were microscopically confirmed. Bed-sharing and having contact history were independent predictors of microscopically confirmed scabies. The prevalence of secondary bacterial infections among scabies-confirmed patients was 35.9% (56/156). The most prevalent bacterial species were Staphylococcus aureus, coagulase-negative staphylococci, and Streptococcus pyogenes. Tetracycline for Gram-positive bacteria and ampicillin for Gram-negative bacteria showed the highest rate of resistance. In both Gram-positive and Gram-negative strains, multidrug resistance was also observed. CONCLUSION: This study found that over one-third of skin scrapings tested positive for scabies. Additionally, more than one-third of scabies cases were complicated by secondary bacterial infections. Improved scabies diagnosis and consideration of secondary bacterial infections are important for better controlling this neglected tropical disease.
Assuntos
Escabiose , Escabiose/epidemiologia , Humanos , Etiópia/epidemiologia , Masculino , Feminino , Estudos Transversais , Adulto , Prevalência , Adolescente , Adulto Jovem , Pessoa de Meia-Idade , Criança , Hospitais Gerais , Coinfecção/epidemiologia , Coinfecção/microbiologia , Coinfecção/parasitologia , Pré-Escolar , Antibacterianos/uso terapêutico , Antibacterianos/farmacologia , Infecções Bacterianas/epidemiologia , Infecções Bacterianas/microbiologia , Fatores de Risco , IdosoRESUMO
The spread of antibiotic resistance (ABR) in uncommon human pathogens endangers global public health, escalating morbidity, death, and healthcare expenditures. Pantoea agglomerans, a member of the Erwiniaceae family that rarely infects humans, is emerging as a drug-resistant nosocomial pathogen. Seven P. agglomerans isolates were recovered from bacteremia patients at a tertiary care hospital in Kolkata, West Bengal, between March 2022 and October 2022. The isolates were evaluated for phenotypic resistance, ß-lactamase and plasmid-mediated quinolone resistance (PMQR) genes, plasmid profiling, and clonality assessment. All isolates were resistant to fluoroquinolones and third-generation cephalosporins, with four resistant to carbapenems. The following ß-lactamases and PMQR genes were identified: blaOXA-1 (n = 1), blaTEM (n = 1), blaCTX-M-1 (n = 2), blaNDM (n = 5), blaOXA-181 (n = 1), qnrB (n = 2), and qnrS (n = 4). Six isolates carried up to seven plasmids ranging in size from 2 kb to > 212 kb. IncFI, FII, HI, and X3 plasmid types were detected in three isolates, while the rest remained untypable. Four different genetic patterns were noted. Four isolates were clonally related, with three being clonal. The swap of environmental isolates to human pathogens exacerbates the ABR dilemma, periling patient care and outcomes. This is the first report in India of a carbapenem-resistant P. agglomerans blood isolate carrying blaOXA-181. In-depth genomic research of drug-resistant microbes adapted to the environment-human interfaces might underpin the source-route-containment of ABR.
Assuntos
Antibacterianos , Bacteriemia , Carbapenêmicos , Pantoea , Plasmídeos , Centros de Atenção Terciária , beta-Lactamases , Humanos , Índia , Centros de Atenção Terciária/estatística & dados numéricos , Bacteriemia/microbiologia , beta-Lactamases/genética , Pantoea/genética , Pantoea/efeitos dos fármacos , Pantoea/isolamento & purificação , Plasmídeos/genética , Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , Testes de Sensibilidade Microbiana , Infecções por Enterobacteriaceae/microbiologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Farmacorresistência Bacteriana Múltipla/genética , MasculinoRESUMO
During extensive field explorations of the Lateritic area in West Bengal, one remarkable wild Russuloid macrofungus, ethnically termed "Kend Patra," was collected. The species was known to enrich the diet of the local people, being considered as income source for some tribal groups. Using morphological characters and molecular analysis of this collection, provide a unique placement of the taxon in the Russula subgenus Compactae (Fr.) Bon. Further in order to find functional constituents for biopharma applications, methanolic extract was prepared that shows the existence of a substantial amounts of phenol, flavonoid, ascorbic acid and carotenoids. Antioxidant activity was determined where the fraction demonstrated strong DPPH, ABTS, and nitric oxide radical scavenging activities, high Fe2+ ion chelating ability, and a reducing power with EC50 values ranging from 538.69 to 891.75 µg/ml. The extract was found to be effective against Listeria monocytogenes, Bacillus subtilis, Pseudomonas aeruginosa, Escherichia coli, Salmonella typhi and Staphylococcus aureus. In addition, the extract exhibited potent anticancer activities as it inhibited A549 cell proliferation, caused morphological changes, elevated ROS levels, hindered the clonogenic ability and migratory potential of cancerous cells, arrested cell cycle progression at S phase, and induced apoptosis by modulating the intrinsic mitochondrial pathway. Overall, this study contributes a new species to the world's myco-diversity and presents an exciting opportunity for future researchers to conduct comprehensive investigations on this unique species in order to uncover potential new medications for human use.