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1.
ACS Appl Mater Interfaces ; 16(29): 37795-37805, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39008846

RESUMO

Biofilm-mediated wound infections pose a significant challenge due to the limitations of conventional antibiotics, which often exhibit narrow-spectrum activity, fail to eliminate recurrent bacterial contamination, and are unable to penetrate the biofilm matrix. While the search for alternatives has explored the use of metal nanoparticles and synthetic biocides, these solutions often suffer from unintended toxicity to surrounding tissues and lack controlled administration and release. In this study, we engineered a pH-responsive release-active dressing film based on carboxymethyl cellulose, incorporating a synthetic antibacterial molecule (SAM-17). The dressing film exhibited optimal mechanical stability for easy application and demonstrated excellent fluid absorption properties, allowing for prolonged moisturization at the site of injury. The film exhibited pH-dependent release of cargo, with 78% release within 24 h at acidic pH, enabling targeted antibacterial drug delivery within the wound microenvironment. Furthermore, the release-active film effectively eliminated repeated challenges of bacterial contamination. Remarkably, the film demonstrated a minimal toxicity profile in both in vitro and in vivo models. The film eliminated preformed bacterial biofilms, achieving a reduction of 2.5 log against methicillin-resistant Staphylococcus aureus (MRSA) and 4.1 log against vancomycin-resistant S. aureus (VRSA). In a biofilm-mediated MRSA wound infection model, this release-active film eradicated the biofilm-embedded bacteria by over 99%, resulting in accelerated wound healing. These findings highlight the potential of this film as an effective candidate for tackling biofilm-associated wound infections.


Assuntos
Antibacterianos , Bandagens , Biofilmes , Staphylococcus aureus Resistente à Meticilina , Infecção dos Ferimentos , Biofilmes/efeitos dos fármacos , Antibacterianos/química , Antibacterianos/farmacologia , Infecção dos Ferimentos/tratamento farmacológico , Infecção dos Ferimentos/microbiologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/fisiologia , Animais , Camundongos , Concentração de Íons de Hidrogênio , Infecções Estafilocócicas/tratamento farmacológico , Testes de Sensibilidade Microbiana , Humanos , Carboximetilcelulose Sódica/química , Carboximetilcelulose Sódica/farmacologia
2.
Lett Appl Microbiol ; 77(7)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39009015

RESUMO

Lactoferrin is an antimicrobial glycoprotein that demonstrates a broad-spectrum of activity against a wide variety of clinical pathogens. This study investigated the potential of bovine lactoferrin (bLf) against multidrug resistant Staphylococcus capitis (S. capitis) strains. Growth curve analysis and time-kill curves demonstrated that at 750 µg ml-1 lactoferrin significantly inhibited (50.6%, P < 0.05) the growth of most isolates tested (90%), and this effect was based on a bacteriostatic mechanism. At the same concentration, bLf also significantly inhibited (30%, P < 0.05) biofilm formation in 40% of strains tested. Combinations of bLf with selected antibiotics were assessed for enhanced antimicrobial activity using growth curves. BLf combined with ß-lactam antibiotics reduced the growth of S. capitis strains, however, the effects were not significant. BLf displays antimicrobial effects against multidrug resistant S. capitis isolates, but with strain-specific effects.


Assuntos
Antibacterianos , Biofilmes , Lactoferrina , Testes de Sensibilidade Microbiana , Staphylococcus capitis , Lactoferrina/farmacologia , Animais , Bovinos , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Antibacterianos/farmacologia , Staphylococcus capitis/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla , Infecções Estafilocócicas/microbiologia
3.
Microb Pathog ; 194: 106800, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39025380

RESUMO

Candida albicans is a common commensal fungus and fourth most frequent causative agent of nosocomial infections including life-threatening invasive candidiasis in humans. The effectiveness of present antifungal therapies using azoles, polyenes, flucytosine and echinocandins has plateaued in managing fungal infections. The limitations of these antifungal drugs are related to polymorphic morphology, biofilm formation, emergence of drug-resistant strains and production of several virulence factors. Development of new antifungal agents, which can particularly afflict multiple cellular targets and limiting evolving resistant strains are needed. Recently, metal nanoparticles have emerged as a source of new antifungal agents for antifungal formulations. Furthermore, green nanotechnology deals with the use of biosynthetic routes that offer new avenue for synthesizing antifungal nanoparticles coupled with less toxic chemical inventory and environmental sustainability. This article reviews the recent developments on C. albicans pathogenesis, biofilm formation, drug resistance, mode of action of antifungal drugs and antifungal activities of metal nanoparticles. The antifungal efficacy and mode of action of metal nanoparticles are described in the context of prospective therapeutic applications.

4.
mSystems ; : e0036524, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39058093

RESUMO

Bacterial relatedness measured using select chromosomal loci forms the basis of public health genomic surveillance. While approximating vertical evolution through this approach has proven exceptionally valuable for understanding pathogen dynamics, it excludes a fundamental dimension of bacterial evolution-horizontal gene transfer. Incorporating the accessory genome is the logical remediation and has recently shown promise in expanding epidemiological resolution for enteric pathogens. Employing k-mer-based Jaccard index analysis, and a novel genome length distance metric, we computed pangenome (i.e., core and accessory) relatedness for the globally important pathogen Salmonella enterica serotype Typhi (Typhi), and graphically express both vertical (homology-by-descent) and horizontal (homology-by-admixture) evolutionary relationships in a reticulate network of over 2,200 U.S. Typhi genomes. This analysis revealed non-random structure in the Typhi pangenome that is driven predominantly by the gain and loss of mobile genetic elements, confirming and expanding upon known epidemiological patterns, revealing novel plasmid dynamics, and identifying avenues for further genomic epidemiological exploration. With an eye to public health application, this work adds important biological context to the rapidly improving ways of analyzing bacterial genetic data and demonstrates the value of the accessory genome to infer pathogen epidemiology and evolution.IMPORTANCEGiven bacterial evolution occurs in both vertical and horizontal dimensions, inclusion of both core and accessory genetic material (i.e., the pangenome) is a logical step toward a more thorough understanding of pathogen dynamics. With an eye to public, and indeed, global health relevance, we couple contemporary tools for genomic analysis with decades of research on mobile genetic elements to demonstrate the value of the pangenome, known and unknown, annotated, and hypothetical, for stratification of Salmonella enterica serovar Typhi (Typhi) populations. We confirm and expand upon what is known about Typhi epidemiology, plasmids, and antimicrobial resistance dynamics, and offer new avenues of exploration to further deduce Typhi ecology and evolution, and ultimately to reduce the incidence of human disease.

5.
J Med Microbiol ; 73(7)2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39057747

RESUMO

The application of a One Health approach recognizes that human health, animal health, plant health and ecosystem health are intrinsically connected. Tackling complex challenges associated with foodborne zoonoses, antimicrobial resistance, and emerging threats is imperative. Therefore, the One Health European Joint Programme was established within the European Union research programme Horizon 2020. The One Health European Joint Programme activities were based on the development and harmonization of a One Health science-based framework in the European Union (EU) and involved public health, animal health and food safety institutes from almost all EU Member States, the UK and Norway, thus strengthening the cooperation between public, medical and veterinary organizations in Europe. Activities including 24 joint research projects, 6 joint integrative projects and 17 PhD projects, and a multicountry simulation exercise facilitated harmonization of laboratory methods and surveillance, and improved tools for risk assessment. The provision of sustainable solutions is integral to a One Health approach. To ensure the legacy of the work of the One Health European Joint Programme, focus was on strategic communication and dissemination of the outputs and engagement of stakeholders at the national, European and international levels.


Assuntos
União Europeia , Saúde Única , Humanos , Animais , Saúde Pública , Europa (Continente) , Zoonoses/prevenção & controle , Comunicação , Inocuidade dos Alimentos
6.
BMC Complement Med Ther ; 24(1): 272, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39026301

RESUMO

BACKGROUND: Cymbopogon is a member of the family Poaceae and has been explored for its phytochemicals and bioactivities. Although the antimicrobial activities of Cymbopogon spp. extracts have been extensively studied, comprehensive analyses are required to identify promising compounds for the treatment of antimicrobial resistance. Therefore, this study investigated the antioxidant and antimicrobial properties of Cymbopogon spp. ethanolic extracts in every single organ. METHODS: Ethanolic extracts were obtained from three Indonesian commercial species of Cymbopogon spp., namely Cymbopogon citratus (L.) Rendle, Cymbopogon nardus (DC.) Spatf., and Cymbopogon winterianus Jowitt. The leaf, stem, and root extracts were evaluated via metabolite profiling using gas chromatography-mass spectrometry (GC-MS). In silico and in vitro analyses were used to evaluate the antioxidant and antimicrobial properties of the Cymbopogon spp. ethanolic extracts. In addition, bioactivity was measured using cytotoxicity assays. Antioxidant assays were performed using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2-azino-bis [3-ethylbenzothiazoline-6-sulfonic acid (ABTS) to determine toxicity to Huh7it-1 cells using a tetrazolium bromide (MTT) assay. Finally, the antimicrobial activity of these extracts was evaluated against Candida albicans, Bacillus subtilis, Staphylococcus aureus, and Escherichia coli using a well diffusion assay. RESULTS: GC-MS analysis revealed 53 metabolites. Of these, 2,5-bis(1,1-dimethylethyl)- phenol (27.87%), alpha-cadinol (26.76%), and 1,2-dimethoxy-4-(1-propenyl)-benzene (20.56%) were the predominant compounds. C. winterianus and C. nardus leaves exhibited the highest antioxidant activity against DPPH and ABTS, respectively. Contrastingly, the MTT assay showed low cytotoxicity. C. nardus leaf extract exhibited the highest antimicrobial activity against E. coli and S. aureus, whereas C. winterianus stem extract showed the highest activity against B. substilis. Furthermore, computational pathway analysis predicted that antimicrobial activity mechanisms were related to antioxidant activity. CONCLUSIONS: These findings demonstrate that the leaves had strong antioxidant activity, whereas both the leaves and stems showed great antimicrobial activity. Furthermore, all Cymbopogon spp. ethanolic extracts showed low toxicity. These findings provide a foundation for future studies that assess the clinical safety of Cymbopogon spp. as novel drug candidates.


Assuntos
Anti-Infecciosos , Antioxidantes , Cymbopogon , Extratos Vegetais , Folhas de Planta , Raízes de Plantas , Antioxidantes/farmacologia , Antioxidantes/química , Cymbopogon/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Folhas de Planta/química , Raízes de Plantas/química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Caules de Planta/química , Testes de Sensibilidade Microbiana , Humanos , Cromatografia Gasosa-Espectrometria de Massas , Indonésia
7.
Artigo em Inglês | MEDLINE | ID: mdl-39044541

RESUMO

AIMS: Judicious antimicrobial use in companion animal practice is critical for maintaining the effectiveness of antimicrobial agents against bacterial infections and reducing the selection of antimicrobial-resistant bacteria. This study aimed to provide insights into companion animal veterinarians' antimicrobial treatment recommendations for common bacterial infections in dogs and cats and describe the factors influencing their prescription choices. METHODS AND RESULTS: An online survey using QualtricsXM® software was administered between September and November 2022 to companion animal veterinarians who were Illinois State Veterinary Medical Association members. Descriptive and text analyses were conducted to assess the participants' responses. A total of 78 surveys were included in the analysis. Skin infections were ranked as the most common bacterial infections for which veterinarians prescribed antimicrobial agents, followed by ear, urinary tract, respiratory, and enteric infections. The severity of clinical symptoms and the results of bacterial culture and susceptibility tests were the most influential factors for veterinarians when making antimicrobial prescription choices. Veterinarians were aware of the current antimicrobial prescription guideline recommendations when prescribing antimicrobials empirically to nine hypothetical scenarios of bacterial infections. According to the results of the text analysis that assessed veterinarians' responses to an open-ended question, regarding their challenges when prescribing antimicrobial agents, the pairwise correlation of word frequencies within each response showed the highest correlations between the words 'owner' and 'compliance', 'administration' and 'route', 'cost' and 'culture', and 'patients' and 'acceptance'. CONCLUSIONS: The study results can support animal health stakeholders in the development of antimicrobial stewardship programmes to promote appropriate antimicrobial use and limit the emergence of antimicrobial resistance.

8.
Clin Infect Dis ; 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39045871

RESUMO

There is an unmet need for developing drugs for the treatment of gonorrhea, due to rapidly evolving resistance of Neisseria gonorrhoeae against antimicrobial drugs used for empiric therapy, an increase in globally reported multidrug resistant cases, and the limited available therapeutic options. Furthermore, few drugs are under development. Development of antimicrobials is hampered by challenges in clinical trial design, limitations of available diagnostics, changes in and varying standards of care, lack of robust animal models, and clinically relevant pharmacodynamic targets. On April 23, 2021, the U.S. Food and Drug Administration; Centers for Disease Control and Prevention; and National Institute of Allergy and Infectious Diseases, National Institutes of Health co-sponsored a workshop with stakeholders from academia, industry, and regulatory agencies to discuss the challenges and strategies, including potential collaborations and incentives, to facilitate the development of drugs for the treatment of gonorrhea. This article provides a summary of the workshop.

9.
Microbiol Spectr ; : e0393423, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39046262

RESUMO

Efflux pumps and biofilm play significant roles in bacterial antibiotic resistance. This study investigates the potential of chlorogenic acid (CGA) and carnosol (CL), as phenolic and diterpene compounds, respectively, for their inhibitory effects on efflux pumps. Among the 12 multidrug-resistant (MDR) strains of Staphylococcus aureus and Pseudomonas aeruginosa isolated from nosocomial skin infections, eight strains were identified as extensively drug resistant (XDR) using the disc diffusion method. The presence of efflux pumps in MDR strains of S. aureus and P. aeruginosa was screened using carbonyl cyanide-m-chlorophenylhydrazone. Between the 12 MDR strains of S. aureus and P. aeruginosa, 80% (4 out of 5) of the S. aureus strains and 85.7% (6 out of 7) of the P. aeruginosa strains exhibited active efflux pumps associated with gentamicin resistance. The checkerboard assay results, in combination with gentamicin, demonstrated that CGA exhibited a reduction in the minimum inhibitory concentration (MIC) for XDR S. aureus strain. Similarly, CL showed a synergistic effect and reduced the MIC for both XDR strains of S. aureus and P. aeruginosa. Flow cytometry was used to examine efflux pump activity at sub-MIC concentrations of 1/8, 1/4, and 1/2 MIC in comparison to the control. In XDR S. aureus, CGA demonstrated 39%, 70%, and 19% inhibition, while CL exhibited 74%, 73.5%, and 62% suppression. In XDR P. aeruginosa, CL exhibited inhibition rates of 25%, 10%, and 15%. The inhibition of biofilm formation was assessed using the microtiter plate method, resulting in successful inhibition of biofilm formation. Finally, the MTT assay was conducted, and it confirmed minimal cytotoxicity. Given the significant reduction in efflux pump activity and biofilm formation observed with CGA and CL in this study, these compounds can be considered as potential inhibitors of efflux pumps and biofilm formation, offering potential strategies to overcome antimicrobial resistance. IMPORTANCE: In summary, CGA and CL demonstrated promising potentiating antimicrobial effects against XDR strains of Staphylococcus aureus and Pseudomonas aeruginosa, suggesting their probably potential as candidates for addressing nosocomial pathogens. They exhibited significant suppression of efflux pump activity, indicating a possible successful inhibition of this mechanism. Moreover, all substances effectively inhibited biofilm formation, while showing minimal cytotoxicity. However, further advancement to clinical trials is needed to evaluate the feasibility of utilizing CGA and CL for reversing bacterial XDR efflux and determining their efficacy against biofilms. These trials will provide valuable insights into the practical applications of these compounds in combating drug-resistant infections.

11.
Cell Rep ; 43(7): 114449, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-38985680

RESUMO

Some microbial toxins also target the producer species itself, necessitating a means of self-protection. The M2 double-stranded RNA (dsRNA) killer virus in Saccharomyces cerevisiae contains a single open reading frame (ORF) encoding both the secreted pore-forming toxin K2 as well as a cognate immunity factor. Here, we show that expression of a 49-amino acid N-terminal peptide from the K2 precursor is both necessary and sufficient for immunity. This immunity peptide simultaneously functions as a signal peptide for toxin secretion and protects the cell against the cytotoxic K2 α subunit. The K2 toxin and immunity factor can be functionally separated into two ORFs, yielding a modular toxin-immunity system. This case further shows how a (signal) peptide can carry the potential for providing cellular protection against an antimicrobial toxin.


Assuntos
Fatores Matadores de Levedura , Sinais Direcionadores de Proteínas , Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Fatores Matadores de Levedura/metabolismo , Fases de Leitura Aberta/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética
12.
Prev Vet Med ; 230: 106287, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39059075

RESUMO

Limiting the use of antimicrobial agents in intensive livestock production is a challenge due to different perceptions between the short-term benefits of antimicrobial use (AMU) by livestock producers and the long-term social costs of antimicrobial resistance (AMR) and its impact on human, animal, and environmental health. Pig farmers are key stakeholders supporting Thailand's national strategic plan on AMR which aims to reduce antimicrobial consumption in the livestock sector. Consequently, this study explored the knowledge, perceptions, attitudes, and practices of pig farmers towards AMU and AMR, expecting to provide information that would help guide policymakers in the development of a proper interventional program for antimicrobial stewardship. The qualitative approach utilized individual, face-to-face, in-depth, semi-structured interviews with the 20 owners of middle- and large-scale pig farms in eastern Thailand. The major themes identified in this finding were: (1) the use of antimicrobials on farms and the knowledge of antimicrobials; (2) AMU on pig farms (the purpose of AMU, antimicrobial prescription practices, and performing antimicrobial susceptibility testing); (3) attitudes towards prescribing practices and record keeping; (4) farm animal husbandry practices and AMU; (5) factors influencing AMU; and (6) awareness regarding AMR. Most of the pig farm owners recognized that achieving Good Agricultural Practices certification required following the legislation and regulations for AMU. Other observations were that the respondents had positive attitudes towards prescribing practices, performing antimicrobial susceptibility testing before antimicrobial therapy, and recording drug use on farms; however, there was low awareness of AMR. In addition, alternative substances, such as medicinal plants, and proper biosecurity practices were mentioned. Factors influencing AMU on pig farms were intensive enforcement of legislation and regulations, the implementation of farm management practices, the provision of information and consultancy services by veterinary professionals, farmer experience, and consumer trends.

13.
Biology (Basel) ; 13(7)2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-39056680

RESUMO

Porins are crucial proteins located in the outer membrane that directly influence antimicrobial resistance mechanisms and virulence in bacteria. In this study, a porin gene (Vp-porin) was cloned in V. parahaemolyticus, and the function of Vp-Porin in biological characteristics and virulence was investigated. The results of sequence analysis showed that Vp-Porin is highly conserved in Vibrio spp., and the predicted 3D structure showed it could form a 20-strand transmembrane ß-barrel domian. Membrane permeabilization provides evidence that the membrane integrity of ∆Vp-porin was damaged and the sensitivity to tetracycline, polymyxin B, rifampicin and cephalothin of ∆Vp-porin obviously increased. In addition, loss of Vp-porin damaged motility due to downregulated flagellar synthesis. In addition, ∆Vp-porin exhibited attenuated cytotoxicity to Tetrahymena. The relative survival rate of Tetrahymena infection with ∆Vp-porin was 86%, which is much higher than that with WT (49%). Taken together, the results of this study indicate that Vp-Porin in V. parahaemolyticus plays various roles in biological characteristics in membrane integrity, antimicrobial resistance and motility and contributes to virulence.

14.
Curr Issues Mol Biol ; 46(7): 7447-7472, 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39057083

RESUMO

Even with the intensive efforts by public health programs to control and prevent it, non-typhoidal Salmonella (NTS) infection remains an important public health challenge. It is responsible for approximately 150 million illnesses and 60,000 deaths worldwide annually. NTS infection poses significant risks with high rates of morbidity and mortality, leading to potential short- and long-term complications. There is growing concern among health authorities about the increasing incidence of antimicrobial resistance, with multidrug resistance totaling 22.6% in Europe, highlighting an urgent need for new therapeutic approaches. Our review aims to provide a comprehensive overview of NTS infection. We outline the molecular mechanisms involved in the pathogenesis of NTS infection, as well as the events leading to invasive NTS infection and the subsequent complications associated with it. Given the widespread implications of antimicrobial resistance, our review also presents the global landscape of resistance, including multidrug resistance, and delve into the underlying mechanisms driving this resistance. The rising rates of antibiotic resistance frequently lead to treatment failures, emphasizing the importance of investigating alternative therapeutic options. Therefore, in this review we also explore potential alternative therapies that could offer promising approaches to treating NTS infections.

15.
Pathogens ; 13(7)2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-39057765

RESUMO

BACKGROUND: Tolerance enables bacteria to survive intermittent antibiotic exposure without an increase in antimicrobial susceptibility. In this study, we investigated the presence of tolerance to three antimicrobials, ceftriaxone, azithromycin and ciprofloxacin, in clinical isolates and the WHO (World Health Organization) reference panel of Neisseria gonorrhoeae. METHODS: We used the modified tolerance disk (TD test) to assess for tolerance to ceftriaxone, azithromycin and ciprofloxacin in 14 WHO reference strains and 62 N. gonorrhoeae clinical isolates-evenly divided between anorectal and urogenital infections. The isolates underwent a three-step incubation process wherein the isolates were exposed to an antibiotic disk for 20 h of incubation (Step I), followed by the replacement of the antibiotic disk with a nutrient disk for overnight incubation (Step II) and additional overnight incubation with extra nutrients (Step III). RESULTS: A total of 4 of the 62 clinical anorectal isolates and none of the urogenital isolates exhibited tolerance to azithromycin (p = 0.033). Tolerance to ceftriaxone and ciprofloxacin was observed in eight and four isolates, respectively, with no difference between infection sites. Tolerance was also detected in 8 (K, M, N, O, P, U, V, W) out of the 14 WHO reference strains, with varying patterns of tolerance to ceftriaxone (n = 8), ciprofloxacin (n = 2) and azithromycin (n = 1). CONCLUSIONS: This study identified ceftriaxone, azithromycin and ciprofloxacin tolerance in clinical and WHO reference N. gonorrhoeae isolates. Azithromycin tolerance was more common in anorectal than urogenital infections.

16.
Vet Sci ; 11(7)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39057979

RESUMO

Food safety for cricket production is a crucial factor in producing edible crickets with safety for consumers and sustainability for two-spotted (Gryllus bimaculatus) as well as house (Acheta domesticus) cricket production. This study was conducted by simultaneously rearing two cricket species, comprising two-spotted crickets (G. bimaculatus) and house crickets (A. domesticus). A total of 16 rearing crates were used for the present study, which were allocated into 8 rearing crates for each studied cricket species, including paper egg cartons. Cricket eggs were incubated in the rearing crates. Once the crickets hatched, tap water and powdered feed were provided ad libitum throughout the experiment. At the end of this study (35 and 42 days for the two-spotted and house crickets, respectively), all crickets were harvested, rinsed in tap water, and boiled in water for 5 min. During the rearing and harvesting processes, samples were collected from various potential contamination points for bacteria, including E. coli and Salmonella spp. There were samples of the initial input (feed, drinking water, and staff hands), rearing environment (water pipe, crate wall, living cartons, frass, and cricket surface), and harvesting crickets (harvested, washed, and boiled crickets), with a 2-week sampling interval, except for the last round of sampling for the two-spotted crickets. Subsequently, all samples were submitted to isolate and identify contaminated bacteria. The samples from the last round of sampling for both kinds of crickets were submitted to quantify the level of contamination for E. coli and Salmonella spp., including antimicrobial resistance by the disk diffusion method for the positive isolate. The results showed that bacterial contamination was found in the rearing of both cricket species, primarily involving Klebsiella spp. and Enterobacter spp., mainly found in prepared drinking water and the water pipes of drinking water supply equipment, which are potential sources of contamination with cricket frass. E. coli was found in 4.8% and 4.3% of the two-spotted and house crickets, respectively, while no presence of Salmonella spp. was detected in any submitted samples. The quantification of E. coli and Salmonella spp. indicated E. coli contamination near the water pipe and the frass of two-spotted crickets, but Salmonella spp. was undetectable in both two-spotted and house crickets. The antimicrobial resistance of isolated E. coli mainly involved penicillin G, amoxicillin, ampicillin, erythromycin, lincomycin, and tiamulin. Thus, good farm management with proper sanitation practices (such as cleaning and keeping the environment dry), as well as boiling crickets during the harvesting process, may help ensure the safety of edible cricket production.

17.
Vet Sci ; 11(7)2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39057999

RESUMO

Salmonella spp. pose a global threat as a leading cause of foodborne illnesses, particularly prevalent in the European Union (EU), where it remains the second cause of foodborne outbreaks. The emergence of antimicrobial resistance (AMR) in Salmonella spp. has become a critical concern, complicating treatment strategies and escalating the risk of severe infections. The study focuses on large and small ruminants, identifying a prevalence of Salmonella spp. in slaughterhouses and revealing varied AMR rates across antimicrobial families throughout a meta-analysis. Also, comparison with AMR in human medicine was carried out by a systematic review. The results of the present meta-analysis displayed a prevalence of Salmonella spp. in large and small ruminants at slaughterhouses of 8.01% (8.31%, cattle; 7.04%, goats; 6.12%, sheep). According to the AMR of Salmonella spp., 20, 14, and 13 out of 62 antimicrobials studied were classified as low (<5%), high (>5% but <10%), and very high (>10%), respectively. Salmonella spp. did not display AMR against aztreonam, mezlocillin, ertapenem, meropenem, cefoxitin, ceftazidime, levofloxacin, tilmicosin, linezolid, fosfomycin, furazolidone, quinupristin, trimethoprim and spectinomycin. In contrast, a prevalence of 100% of AMR has been described against ofloxacin, lincomycin, and cloxacillin. In the context of the main antibiotics used in the treatment of human salmonellosis, azithromycin was shown to have the highest resistance among Salmonella spp. isolates from humans. Regarding cephalosporins, which are also used for the treatment of salmonellosis in humans, the prevalence of Salmonella spp. resistance to this class of antibiotics was similar in both human and animal samples. Concerning quinolones, despite a heightened resistance profile in Salmonella spp. isolates from ruminant samples, there appears to be no discernible compromise to the efficacy of salmonellosis treatment in humans since lower prevalences of AMR in Salmonella spp. isolated from human specimens were observed. Although the resistance of Salmonella spp. indicates some degree of concern, most antibiotics are not used in veterinary medicine. Thus, the contribution of cattle, sheep and goats to the rise of antibiotic resistance of Salmonella spp. and its potential impact on public health appears to be relatively insignificant, due to their low prevalence in carcasses and organs. Nevertheless, the observed low prevalence of Salmonella spp. in ruminants at slaughterhouse and the correspondingly low AMR rates of Salmonella spp. to key antibiotics employed in human medicine do not indicate that ruminant livestock poses a substantial public health risk concerning the transmission of AMR. Thus, the results observed in both the meta-analysis and systematic review suggests that AMR is not solely attributed to veterinary antibiotic use but is also influenced by factors such as animal health management (i.e., biosecurity measures, prophylactic schemes) and human medicine.

18.
JMIR Form Res ; 8: e54458, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39059001

RESUMO

BACKGROUND: Antimicrobial resistance (AMR) represents a growing concern for public health. OBJECTIVE: We sought to explore the challenges associated with development and implementation of a complex intervention designed to improve AMS in hospitals. METHODS: We conducted a qualitative evaluation of a complex AMS intervention with educational, behavioral, and technological components in 5 wards of an English hospital. At 2 weeks and 7 weeks after initiating the intervention, we interviewed 25 users of the intervention, including senior and junior prescribers, a senior nurse, a pharmacist, and a microbiologist. Topics discussed included perceived impacts of different elements of the intervention and facilitators and barriers to effective use. Interviews were supplemented by 2 observations of ward rounds to gain insights into AMS practices. Data were audio-recorded, transcribed, and inductively and deductively analyzed thematically using NVivo12. RESULTS: Tracing the adoption and impact of the various components of the intervention was difficult, as it had been introduced into a setting with competing pressures. These particularly affected behavioral and educational components (eg, training, awareness-building activities), which were often delivered ad hoc. We found that the participatory intervention design had addressed typical use cases but had not catered for edge cases that only became visible when the intervention was delivered in real-world settings (eg, variations in prescribing workflows across different specialties and conditions). CONCLUSIONS: Effective user-focused design of complex interventions to promote AMS can support acceptance and use. However, not all requirements and potential barriers to use can be fully anticipated or tested in advance of full implementation in real-world settings.

19.
Microbiol Res ; 287: 127837, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39059097

RESUMO

Klebsiella pneumoniae, a prominent nosocomial pathogen, poses a critical global health threat due to its multidrug-resistant (MDR) and hypervirulent strains. This comprehensive review focuses into the complex approaches undertaken in the development of vaccines against K. pneumoniae. Traditional methods, such as whole-cell and ribosomal-based vaccines, are compared with modern strategies, including DNA and mRNA vaccines, and extracellular vesicles (EVs), among others. Each method presents unique advantages and challenges, emphasising the complexity of developing an effective vaccine against this pathogen. Significant advancements in computational tools and artificial intelligence (AI) have revolutionised antigen identification and vaccine design, enhancing the precision and efficiency of developing multiepitope-based vaccines. The review also highlights the potential of glycomics and immunoinformatics in identifying key antigenic components and elucidating immune evasion mechanisms employed by K. pneumoniae. Despite progress, challenges remain in ensuring the safety, efficacy, and manufacturability of these vaccines. Notably, EVs demonstrate promise due to their intrinsic adjuvant properties and ability to elicit robust immune responses, although concerns regarding inflammation and antigen variability persist. This review provides a critical overview of the current landscape of K. pneumoniae vaccine development, stressing the need for continued innovation and interdisciplinary collaboration to address this pressing public health issue. The integration of advanced computational methods and AI holds the potential to accelerate the development of effective immunotherapies, paving the way for novel vaccines against MDR K. pneumoniae.

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