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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.
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Campylobacter , Farmacorresistencia Bacteriana , Aprendizaje Automático , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Campylobacter/efectos de los fármacos , Antibacterianos/farmacología , Humanos , Microbiología de Alimentos/métodos , Pruebas de Sensibilidad Microbiana/métodos , Enfermedades Transmitidas por los Alimentos/microbiología , Bacterias/efectos de los fármacosRESUMEN
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.
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Antibacterianos , Ácido Clorogénico , Ácidos Cumáricos , Sinergismo Farmacológico , Shigella dysenteriae , Antibacterianos/farmacología , Antibacterianos/química , Ácidos Cumáricos/farmacología , Ácidos Cumáricos/química , Ácido Clorogénico/farmacología , Ácido Clorogénico/química , Shigella dysenteriae/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Biopelículas/efectos de los fármacos , Propionatos/farmacología , Solanum lycopersicum/química , Solanum lycopersicum/microbiología , Conservación de Alimentos/métodosRESUMEN
Alicyclobacillus spp. is a potential spoiling agent of acidic products and citrus drinks, leading to sensory alterations in contaminated products and consequent economic losses. Treatments such as pasteurization eliminate vegetative cells, but also create a favorable atmosphere for spore germination. To guarantee quality and safety, the application of natural substances as bioconservatives is a considerable and promising alternative for the food industry. This study evaluated the effect of hexane extract of Matricaria chamomilla L. (HE), Nisin (N) and their combination (HE + N). These compounds are present in some studies describing their antibacterial action, but no studies were found on the association of these compounds against the species Alicyclobacillus spp. This study aimed to analyze the antioxidant activity (AA) for the DPPH⢠(0,23 µmol Trolox/mg) and ABTS (27.93 µmol Trolox/mg), the Checkboard test revealed synergism between HE and N with a fractional inhibitory index (FIC) of 0.068., and to study the antibacterial and sporicidal effect. The antibacterial and sporicidal activity was satisfactory against Alicyclobacillus acidoterrestris with MIC and MBC of 1.95 µg/mL and MSC of 7.81 µg/mL in analyzes using HE + N. The application in orange juice proved to be effective, with an MBC of 0.007 µg/mL. The MIC results served as a parameter for other tests carried out in this study, such as flow cytometry and Scanning Electron Microscopy (SEM), and for the evaluation of sensory characteristics with Electronic Nose (E-nose).
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Alicyclobacillus , Antibacterianos , Matricaria , Pruebas de Sensibilidad Microbiana , Nisina , Extractos Vegetales , Nisina/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Extractos Vegetales/farmacología , Extractos Vegetales/química , Alicyclobacillus/efectos de los fármacos , Alicyclobacillus/crecimiento & desarrollo , Matricaria/química , Antioxidantes/farmacología , Antioxidantes/químicaRESUMEN
Objective: This study aimed to evaluate antibiotic susceptibility and antimicrobial resistance trends among clinically significant anaerobes in Kuwait hospitals from 2013 to 2022, comparing these findings with data from 2002 to 2012. Methods: The study prospectively collected 2,317 anaerobic isolates from various body sites across four Kuwaiti hospitals between January 2013 and December 2022. The minimum inhibitory concentrations for 11 antianaerobic antibiotics were determined using E-test methodology. The study analyzed trends and resistance rates across two periods: 2013-2017 and 2018-2022, using statistical analysis for resistance comparison. Results: Of the 2,317 isolates, most were from wounds (42.2%), fluids (28.0%), and tissues (20.5%). Bacteroides fragilis was the most common pathogen (34.0%), followed by Prevotella bivia (13.4%). Over 90% of isolates were susceptible to imipenem, meropenem, tigecycline, and metronidazole, whereas lower susceptibility was observed for penicillin, amoxicillin-clavulanic acid, and clindamycin. Notable differences in resistance profiles since 2002 were observed, especially in amoxicillin-clavulanic acid, piperacillin, piperacillin-tazobactam, and clindamycin. Conclusion: Owing to detected resistance to all antibiotics, susceptibility testing for anaerobic isolates is recommended in severe infections to ensure effective antimicrobial therapy. Continuous surveillance is crucial for developing antibiotic policies to manage invasive anaerobic infections.
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Antibacterianos , Bacterias Anaerobias , Pruebas de Sensibilidad Microbiana , Antibacterianos/farmacología , Bacterias Anaerobias/efectos de los fármacos , Kuwait/epidemiología , Humanos , Estudios Prospectivos , Tigeciclina/farmacología , Farmacorresistencia Bacteriana , Bacteroides fragilis/efectos de los fármacos , Bacteroides fragilis/aislamiento & purificación , Metronidazol/farmacología , Metronidazol/uso terapéuticoRESUMEN
The study investigates the potential of Rhizoclonium hieroglyphicum as a novel source for synthesizing nickel oxide nanoparticles (RH-NiONPs) and evaluates its biological applications. Phytochemicals in the algal extract serve as capping, reducing and stabilizing agent for nickel oxide nanoparticles. The process variables were optimized using BBD based RSM to obtain maximum RH-NiONPs. Characterization of RH-NiONPs using UV-Vis and FT-IR spectroscopy reveals the plasmon resonance peak at 340 nm and the functional groups responsible for reduction and stabilization. XRD confirmed the crystalline nature while the stability and size of the RH-NiONPs were determined by DLS and zeta potential. Toxicity assessments demonstrated the effect of RH-NiONPs against Vigna radiata, Allium cepa and Artemia salina was low. RH-NiONPs revealed significant zone of inhibition against the selected bacteria and fungi. The results of larvicidal activity showed that RH-NiONPs are toxic to 4th instar larvae of Daphnis nerii. Also, RH-NiONPs efficiently decolorized Reactive Violet 13 (92%) under sunlight irradiation and the experimental data well fits to Langmuir isotherm along with pseudo second order kinetic model. The thermodynamic studies enunciate the exothermic and non-spontaneous photocatalytic decolorization of reactive violet 13. Thus, the current study assesses the eco-friendly and cost-effective nature of RH-NiONPs along with its biological applications.
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Artemia , Nanopartículas del Metal , Níquel , Extractos Vegetales , Níquel/química , Níquel/farmacología , Animales , Extractos Vegetales/química , Extractos Vegetales/farmacología , Nanopartículas del Metal/química , Artemia/efectos de los fármacos , Cebollas/química , Cebollas/efectos de los fármacos , Daphnia/efectos de los fármacos , Vigna/química , Propiedades de Superficie , Larva/efectos de los fármacos , Tamaño de la Partícula , Pruebas de Sensibilidad Microbiana , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/síntesis químicaRESUMEN
Antimicrobial resistance (AMR) is global health concern escalating rapidly in both clinical settings and environment. The effluent from pharmaceuticals and hospitals may contain diverse antibiotics, exerting selective pressure to develop AMR. To study the aquatic prevalence of drug-resistant staphylococci, sampling was done from river Yamuna (3 sites) and wastewater (7 sites) near pharmaceutical industries in Delhi-NCR, India. 59.25% (224/378) were considered presumptive staphylococci while, methicillin resistance was noted in 25% (56/224) isolates. Further, 23 methicillin-resistant coagulase negative staphylococci (MR-CoNS) of 8 different species were identified via 16S rRNA gene sequencing. Multidrug resistance (MDR) was noted in 60.87% (14/23) isolates. PCR based detection of antibiotic resistance genes revealed the number of isolates containing mecA (7/23), blaZ (6/23), msrA (10/23), aac(6')aph (2") (2/23), aph(3')-IIIa (2/23), ant(4')-Ia (1/23), dfrG (4/23), dfrA(drfS1) (3/23), tetK (1/23) and tetM (1/23). The current research highlights the concerning prevalence of MDR-CoNS in aquatic environment in Delhi.
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Antibacterianos , Coagulasa , Farmacorresistencia Bacteriana Múltiple , ARN Ribosómico 16S , Staphylococcus , Aguas Residuales , India/epidemiología , Aguas Residuales/microbiología , Staphylococcus/genética , Staphylococcus/efectos de los fármacos , Staphylococcus/aislamiento & purificación , Staphylococcus/clasificación , Farmacorresistencia Bacteriana Múltiple/genética , Coagulasa/metabolismo , Coagulasa/genética , ARN Ribosómico 16S/genética , Antibacterianos/farmacología , Prevalencia , Pruebas de Sensibilidad MicrobianaRESUMEN
The microenvironment of wound healing is susceptible to bacterial infection, chronic inflammation, oxidative stress, and inadequate angiogenesis, requiring the development of innovative wound dressings with antibacterial, anti-inflammatory, antioxidant, and angiogenic capabilities. This research crafted a new multifunctional bacterial cellulose composite membrane infused with copper-doped carbon dots (BC/Cu(II)-RCDs). Findings validated the successful loading of copper-doped carbon dots onto the BC membrane via hydrogen bonding interactions. Compared to the pure BC membrane, the BC/Cu(II)-RCDs composite membrane exhibited significantly enhanced hydrophilicity, tensile properties, and thermal stability. Diverse in vitro assays demonstrated excellent biocompatibility and antibacterial activity of BC/Cu(II)-RCDs composite membranes, alongside their ability to expedite the inflammatory phase and stimulate angiogenesis. In vivo trials corroborated the membrane's ability to foster epithelial regeneration, collagen deposition, and tissue regrowth in full-thickness skin wounds in rats while also curbing inflammation in infected full-thickness skin wounds. More importantly, the treatment of the BC/Cu(II)-RCDs composite membrane may result in the activation of VEGF and MAPK signaling proteins, which are key players in cell migration, angiogenesis, and skin tissue development. In essence, the developed BC/Cu(II)-RCDs composite membrane shows promise for treating infected wounds and serves as a viable alternative material for medicinal bandages.
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Antibacterianos , Carbono , Celulosa , Cobre , Cicatrización de Heridas , Cicatrización de Heridas/efectos de los fármacos , Cobre/química , Celulosa/química , Celulosa/farmacología , Animales , Antibacterianos/farmacología , Antibacterianos/química , Carbono/química , Ratas , Humanos , Masculino , Ratas Sprague-Dawley , Staphylococcus aureus/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Puntos Cuánticos/químicaRESUMEN
Perilla essential oil (PLEO) offers benefits for food preservation and healthcare, yet its instability restricts its applications. In this study, chitosan (CS) and TiO2 used to prepare composite particles. TiO2, after being modified with sodium laurate (SL), was successfully introduced at 0.1 %-3 % into the CS matrix. The resulting CS-SL-TiO2 composite particles can be formed by intertwining and rearranging through intramolecular and intermolecular interactions, and form an O/W interface with stability and viscoelasticity. The Pickering emulsions stabilized by these particles exhibit non-Newtonian pseudoplastic behavior, shear-thinning properties, and slow-release characteristics, along with antibacterial activity. Emulsions with 0.5 % and 1 % CS-SL-TiO2 composites demonstrated superior antibacterial effects against Escherichia coli and Staphylococcus aureus. The study revealed that all emulsions undergo Fickian diffusion and a sustained release of PLEO, with the Ritger-Peppas model best describing this release mechanism. The slow-release behaviors positively correlates with interfacial pressure, composite particle size, composite particle potential, composite contact angle, emulsion particle size and emulsion potential, but negatively correlates with diffusion rate, penetration rate, release kinetics and release rate. The findings lay groundwork for developing slow-release antimicrobial emulsions within polysaccharide matrices, showcasing promise for antimicrobial packaging solutions and enhanced food preservation techniques.
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Antibacterianos , Quitosano , Emulsiones , Escherichia coli , Staphylococcus aureus , Titanio , Agua , Quitosano/química , Quitosano/farmacología , Titanio/química , Antibacterianos/química , Antibacterianos/farmacología , Staphylococcus aureus/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Agua/química , Aceites Volátiles/química , Aceites Volátiles/farmacología , Tamaño de la Partícula , Preparaciones de Acción Retardada/química , Aceites de Plantas/química , Aceites de Plantas/farmacología , Pruebas de Sensibilidad Microbiana , Liberación de FármacosRESUMEN
Frequent occurrence of wound infection caused by multiple-resistant bacteria (MRB) has posed a serious challenge to the current healthcare system relying on antibiotics. The development of novel antimicrobial materials with high safety and efficacy to heal wound infection is of great importance in combating this crisis. Herein, we prepared a promising antibacterial hydrogel by cross-linking ferrous ions (Fe2+) with the deprotonated carboxyl anion in sodium alginate (Na-ALG) to cure wound infections caused by methicillin-resistant Staphylococcus aureus (MRSA). Interestingly, ferrous-modified Na-ALG (Fe-ALG) hydrogel demonstrated better properties compared to the traditional Na-ALG-based hydrogels, including injectability, self-healing, appropriate fluidity, high-water retention, potent MRSA-killing efficacy, and excellent biocompatibility. Importantly, the addition of Fe2+ enhances the antibacterial efficacy of the Na-ALG hydrogel, enabling it to effectively eliminate MRSA and accelerate the healing of antibiotic-resistant bacterial-infected wounds in a remarkably short period (10 days). This modification not only facilitates wound closure and fur generation, but also mitigates systemic inflammation, thereby effectively impeding the spread of MRSA to the lungs. Taken together, Fe-ALG hydrogel is a promising therapeutic material for treating wound infections by Staphylococcus aureus, especially by antibiotic-resistant strains like MRSA.
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Alginatos , Antibacterianos , Compuestos Ferrosos , Hidrogeles , Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Cicatrización de Heridas , Infección de Heridas , Alginatos/química , Alginatos/farmacología , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Hidrogeles/química , Hidrogeles/farmacología , Compuestos Ferrosos/química , Compuestos Ferrosos/farmacología , Cicatrización de Heridas/efectos de los fármacos , Antibacterianos/farmacología , Antibacterianos/química , Animales , Infecciones Estafilocócicas/tratamiento farmacológico , Infección de Heridas/tratamiento farmacológico , Infección de Heridas/microbiología , Ratones , Pruebas de Sensibilidad Microbiana , MasculinoRESUMEN
BACKGROUND: Cystic fibrosis (CF), an inherited autosomal recessive disorder, is linked with high morbidity and mortality rates due to bacteria, filamentous, yeast and black yeast-like fungi colonisation in the upper respiratory tract. Although Candida species are the most common fungi isolated from CF patients, azole-resistant Aspergillus fumigatus (ARAf) is a big concern for invasive aspergillosis. Notably, the exact prevalences of Aspergillus species and the prevalence of ARAf isolates among Iranian CF patients have yet to be previously reported and are unknown. We aimed to investigate the prevalence of ARAf isolates in CF patients among Iranian populations by focusing on molecular mechanisms of the mutations in the target gene. METHODS: The 1 year prospective study recovered 120 sputum samples from 103 CF patients. Of these, 55.1% (86/156) yielded Aspergillus species, screened for ARAf using plates containing itraconazole (4 mg/L) and voriconazole (1 mg/L). According to the CLSI-M38 guidelines, antifungal susceptibility testing was performed using the broth microdilution method. In all phenotypically resistant isolates, the target of azole agents, the cyp51A gene, was sequenced to detect any possible single nucleotide polymorphisms (SNP) mediating resistance. RESULTS: Of 120 samples, 101 (84.2%) were positive for filamentous fungi and yeast-like relatives, with 156 fungal isolates. The most common colonising fungi were Aspergillus species (55.1%, 86/156), followed by Candida species (39.8%, 62/156), Exophiala species (3.8%, 6/156) and Scedosporium species (1.3%, 2/156). Forty out of 86 (46.5%) were identified for section Fumigati, 36 (41.9%) for section Flavi, 6 (7%) for section Nigri and 4 (4.6%) for section Terrei. Fourteen out of 40 A. fumigatus isolates were phenotypically resistant. The overall proportion of ARAf in total fungal isolates was 9% (14/156). cyp51A gene analysis in resistant isolates revealed that 13 isolates harboured G448S, G432C, T289F, D255E, M220I, M172V, G138C, G54E and F46Y mutations and one isolate carried G448S, G432C, T289F, D255E, M220I, G138C, G54E and F46Y mutations. Additionally, this study detects two novel cyp51A single-nucleotide polymorphisms (I242V and D490E). CONCLUSIONS: This study first investigated ARAf isolates in Iranian CF patients. Due to a resistance rate of up to 9%, it is recommended that susceptibility testing of Aspergillus isolates from CF patients receiving antifungal treatment be a part of the routine diagnostic workup. However, extensive multicentre studies with a high volume of CF patients are highly warranted to determine the impact of ARAf on CF patients.
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Antifúngicos , Aspergillus fumigatus , Azoles , Fibrosis Quística , Sistema Enzimático del Citocromo P-450 , Farmacorresistencia Fúngica , Proteínas Fúngicas , Pruebas de Sensibilidad Microbiana , Humanos , Fibrosis Quística/microbiología , Fibrosis Quística/complicaciones , Irán/epidemiología , Aspergillus fumigatus/efectos de los fármacos , Aspergillus fumigatus/genética , Aspergillus fumigatus/aislamiento & purificación , Farmacorresistencia Fúngica/genética , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Estudios Prospectivos , Prevalencia , Sistema Enzimático del Citocromo P-450/genética , Azoles/farmacología , Azoles/uso terapéutico , Proteínas Fúngicas/genética , Masculino , Femenino , Aspergilosis/microbiología , Aspergilosis/epidemiología , Aspergilosis/tratamiento farmacológico , Adulto , Niño , Adolescente , Polimorfismo de Nucleótido Simple , Adulto Joven , Esputo/microbiología , Itraconazol/farmacología , Voriconazol/farmacología , Voriconazol/uso terapéutico , Preescolar , MutaciónRESUMEN
Management of urinary tract infections (UTI) is a highly challenging process due to the biofilm-forming ability of human-pathogenic bacteria. Here, we designed to fabricate an effective nanogel with a combination of chitosan bio-polymer and nalidixic acid to prevent biofilm-forming bacterial pathogens. Chitosan-coated nalidixic acid nanogel (NA@CS) exhibits outstanding inhibition potential against bacterial strains. In vitro, anti-bacterial analysis methods (well diffusion, colony-forming assay, and anti-biofilm assay) were performed to study the bacterial inhibition potential of prepared nanogel, which reveals that NA@CS nanogel have greater inhibition potential against selected pathogens. The combination of nalidixic acid with chitosan biopolymer decreases the virulence and pathogenicity of biofilm-forming pathogens due to their ability to membrane phospholipids penetration. Furthermore, the fabricated NA@CS nanogel showed reliable in vitro bio-compatibility on L929 fibroblast cells and in vivo compatibility with Artemia salina animal model. Overall, the results demonstrate that NA@CS nanogel could be an effective therapeutic for treating urinary tract infections and urine bladder wound healing.
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Antibacterianos , Biopelículas , Quitosano , Ácido Nalidíxico , Nanogeles , Infecciones Urinarias , Infecciones Urinarias/microbiología , Infecciones Urinarias/prevención & control , Infecciones Urinarias/tratamiento farmacológico , Quitosano/química , Quitosano/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Animales , Nanogeles/química , Ácido Nalidíxico/farmacología , Biopelículas/efectos de los fármacos , Ratones , Línea Celular , Bacterias/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Humanos , Artemia/efectos de los fármacos , Artemia/microbiologíaRESUMEN
Introduction. Staphylococcus aureus is a leading agent in community-acquired bacteraemia (CAB) and has been linked to elevated mortality rates and methicillin resistance in Costa Rica.Gap statement and aim. To update and enhance previous data obtained in this country, we analysed the clinical manifestations of 54 S. aureus CAB cases in a tertiary hospital and delineated the sequence types (STs), virulome, and resistome of the implicated isolates.Methodology. Clinical information was retrieved from patient files. Antibiotic susceptibility profiles were obtained with disc diffusion and automated phenotypic tests. Genomic data were exploited to type the isolates and for detection of resistance and virulence genes.Results. Primary infections predominantly manifested as bone and joint infections, followed by skin and soft tissue infections. Alarmingly, 70% of patients continued to exhibit positive haemocultures beyond 48 h of treatment modification, with nearly a quarter requiring mechanical ventilation or developing septic shock. The 30-day mortality rate reached an alarming 40%. More than 60% of the patients were found to have received suboptimal or inappropriate antibiotic treatment, and there was an alarming tendency towards the overuse of third-generation cephalosporins as empirical treatment. Laboratory tests indicated elevated creatinine levels, leukocytosis, and bandaemia within the first 24 h of hospitalization. However, most showed improvement after 48 h. The isolates were categorized into 13 STs, with a predominance of representatives from the clonal complexes CC72 (ST72), CC8 (ST8), CC5 (ST5, ST6), and CC1 (ST188). Twenty-four isolates tested positive for mecA, with ST72 strains accounting for 20. In addition, we detected genes conferring acquired resistance to aminoglycosides, MLSB antibiotics, trimethoprim/sulfamethoxazole, and mutations for fluoroquinolone resistance in the isolate collection. Genes associated with biofilm formation, capsule synthesis, and exotoxin production were prevalent, in contrast to the infrequent detection of enterotoxins or exfoliative toxin genes.Conclusions. Our findings broaden our understanding of S. aureus infections in a largely understudied region and can enhance patient management and treatment strategies.
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Antibacterianos , Bacteriemia , Infecciones Comunitarias Adquiridas , Pruebas de Sensibilidad Microbiana , Infecciones Estafilocócicas , Staphylococcus aureus , Centros de Atención Terciaria , Humanos , Costa Rica/epidemiología , Centros de Atención Terciaria/estadística & datos numéricos , Infecciones Comunitarias Adquiridas/microbiología , Infecciones Comunitarias Adquiridas/epidemiología , Infecciones Comunitarias Adquiridas/mortalidad , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/epidemiología , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/mortalidad , Bacteriemia/microbiología , Bacteriemia/epidemiología , Bacteriemia/mortalidad , Bacteriemia/tratamiento farmacológico , Masculino , Staphylococcus aureus/genética , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/aislamiento & purificación , Persona de Mediana Edad , Femenino , Anciano , Adulto , Antibacterianos/uso terapéutico , Antibacterianos/farmacología , Anciano de 80 o más Años , Adulto Joven , Adolescente , Factores de Virulencia/genética , NiñoRESUMEN
BackgroundThe number of cholera cases reported to the World Health Organization (WHO) in 2022 was more than double that of 2021. Nine countries of the WHO European Region reported 51 cases of cholera in 2022 vs five reported cases in 2021.AimWe aimed to confirm that the Vibrio cholerae O1 isolates reported by WHO European Region countries in 2022 belonged to the seventh pandemic El Tor lineage (7PET). We also studied their virulence, antimicrobial resistance (AMR) determinants and phylogenetic relationships.MethodsWe used microbial genomics to study the 49 V. cholerae O1 isolates recovered from the 51 European cases. We also used > 1,450 publicly available 7PET genomes to provide a global phylogenetic context for these 49 isolates.ResultsAll 46 good-quality genomes obtained belonged to the 7PET lineage. All but two isolates belonged to genomic Wave 3 and were grouped within three sub-lineages, one of which, Pre-AFR15, predominated (34/44). This sub-lineage, corresponding to isolates from several countries in Southern Asia, the Middle East and Eastern or Southern Africa, was probably a major contributor to the global upsurge of cholera cases in 2022. No unusual AMR profiles were inferred from analysis of the AMR gene content of the 46 genomes.ConclusionReference laboratories in high-income countries should use whole genome sequencing to assign V. cholerae O1 isolates formally to the 7PET or non-epidemic lineages. Periodic collaborative genomic studies based on isolates from travellers can provide useful information on the circulating strains and their evolution, particularly as concerns AMR.
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Antibacterianos , Cólera , Filogenia , Vibrio cholerae O1 , Vibrio cholerae O1/genética , Vibrio cholerae O1/aislamiento & purificación , Vibrio cholerae O1/clasificación , Cólera/microbiología , Cólera/epidemiología , Humanos , Europa (Continente)/epidemiología , Antibacterianos/farmacología , Secuenciación Completa del Genoma , Pruebas de Sensibilidad Microbiana , Genoma Bacteriano , Genómica , Virulencia/genética , Farmacorresistencia Bacteriana/genéticaRESUMEN
BACKGROUND: Rifampicin resistant tuberculosis remains a global health problem with almost half a million new cases annually. In high-income countries patients empirically start a standardized treatment regimen, followed by an individualized regimen guided by drug susceptibility test (DST) results. In most settings, DST information is not available or is limited to isoniazid and fluoroquinolones. Whole genome sequencing could more accurately guide individualized treatment as the full drug resistance profile is obtained with a single test. Whole genome sequencing has not reached its full potential for patient care, in part due to the complexity of translating a resistance profile into the most effective individualized regimen. METHODS: We developed a treatment recommender clinical decision support system (CDSS) and an accompanying web application for user-friendly recommendation of the optimal individualized treatment regimen to a clinician. RESULTS: Following expert stakeholder meetings and literature review, nine drug features and 14 treatment regimen features were identified and quantified. Using machine learning, a model was developed to predict the optimal treatment regimen based on a training set of 3895 treatment regimen-expert feedback pairs. The acceptability of the treatment recommender CDSS was assessed as part of a clinical trial and in a routine care setting. Within the clinical trial setting, all patients received the CDSS recommended treatment. In 8 of 20 cases, the initial recommendation was recomputed because of stock out, clinical contra-indication or toxicity. In routine care setting, physicians rejected the treatment recommendation in 7 out of 15 cases because it deviated from the national TB treatment guidelines. A survey indicated that the treatment recommender CDSS is easy to use and useful in clinical practice but requires digital infrastructure support and training. CONCLUSIONS: Our findings suggest that global implementation of the novel treatment recommender CDSS holds the potential to improve treatment outcomes of patients with RR-TB, especially those with 'difficult-to-treat' forms of RR-TB.
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Antituberculosos , Sistemas de Apoyo a Decisiones Clínicas , Aprendizaje Automático , Rifampin , Tuberculosis Resistente a Múltiples Medicamentos , Humanos , Rifampin/uso terapéutico , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Antituberculosos/uso terapéutico , Antituberculosos/administración & dosificación , Mycobacterium tuberculosis/efectos de los fármacos , Medicina de Precisión/métodos , Pruebas de Sensibilidad Microbiana , Masculino , Femenino , AdultoRESUMEN
BACKGROUND: Carbapenem-resistant Acinetobacter baumannii (CRAB) frequently causes both healthcare-associated infections and nosocomial outbreaks in burn medicine/plastic surgery and beyond. Owing to the high antibiotic resistance, infections are difficult to treat, and patient outcomes are often compromised. The environmental persistence capability of CRAB favors its transmission in hospitals. A comprehensive analysis and understanding of CRAB epidemiology and microbiology are essential for guiding management. METHODS: A three-year retrospective cohort study (2020-2022) was conducted in a German tertiary burn and plastic surgery center. In addition to epidemiological analyses, microbiological and molecular techniques, including whole-genome sequencing, were applied for the comprehensive examination of isolates from CRAB-positive patients. RESULTS: During the study period, eight CRAB cases were found, corresponding to an overall incidence of 0.2 CRAB cases per 100 cases and an incidence density of 0.35 CRAB cases per 1000 patient-days. Six cases (75%) were treated in the burn intensive care unit, and four cases (50%) acquired CRAB in the hospital. Molecular analyses comprising 74 isolates supported the epidemiologic assumption that hospital acquisitions occurred within two separate clusters. In one of these clusters, environmental CRAB contamination of anesthesia equipment may have enabled transmission. Furthermore, molecular diversity of CRAB isolates within patients was observed. CONCLUSIONS: CRAB can pose a challenge in terms of infection prevention and control, especially if cases are clustered in time and space on a ward. Our study demonstrates that high-resolution phylogenetic analysis of several bacterial isolates from single patients can greatly aid in understanding transmission chains and helps to take precision control measures.
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Infecciones por Acinetobacter , Acinetobacter baumannii , Carbapenémicos , Infección Hospitalaria , Control de Infecciones , Acinetobacter baumannii/genética , Acinetobacter baumannii/efectos de los fármacos , Acinetobacter baumannii/aislamiento & purificación , Humanos , Infecciones por Acinetobacter/epidemiología , Infecciones por Acinetobacter/microbiología , Alemania/epidemiología , Carbapenémicos/farmacología , Estudios Retrospectivos , Masculino , Femenino , Persona de Mediana Edad , Infección Hospitalaria/epidemiología , Infección Hospitalaria/microbiología , Anciano , Adulto , Control de Infecciones/métodos , Epidemiología Molecular , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Quemaduras/microbiología , Quemaduras/complicaciones , Cirugía Plástica , Unidades de Quemados , Secuenciación Completa del Genoma , Incidencia , Pruebas de Sensibilidad MicrobianaRESUMEN
BACKGROUND: Staphylococcus aureus is an infectious bacterium that is frequently found in healthcare settings and the community. This study aimed to prepare rutin-loaded chitosan nanoparticles (Rut-CS NPs) and assess their antibacterial activity against pathogenic strains of S. aureus. RESULTS: The synthesized Rut-CS NPs exhibited an amorphous morphology with a size ranging from 160 to 240 nm and a zeta potential of 37.3 mV. Rut-CS NPs demonstrated significant antibacterial activity against S. aureus strains. Following exposure to Rut-CS NPs, the production of staphyloxanthin pigment decreased by 43.31-89.63%, leading to increased susceptibility of S. aureus to hydrogen peroxide. Additionally, visual inspection of cell morphology indicated changes in membrane integrity and permeability upon Rut-CS NPs exposure, leading to a substantial increase (107.07-191.08%) in cytoplasmic DNA leakage in the strains. Furthermore, ½ MIC of Rut-CS NPs effectively inhibited the biofilm formation (22.5-37.5%) and hemolytic activity (69-82.59%) in the S. aureus strains. CONCLUSIONS: Our study showcases that Rut-CS NPs can serve as a novel treatment agent to combat S. aureus infections by altering cell morphology and inhibiting virulence factors of S. aureus.
Asunto(s)
Antibacterianos , Biopelículas , Quitosano , Pruebas de Sensibilidad Microbiana , Nanopartículas , Rutina , Staphylococcus aureus , Xantófilas , Staphylococcus aureus/efectos de los fármacos , Quitosano/farmacología , Quitosano/química , Rutina/farmacología , Rutina/química , Nanopartículas/química , Antibacterianos/farmacología , Antibacterianos/química , Biopelículas/efectos de los fármacos , Xantófilas/farmacología , Xantófilas/química , Hemólisis/efectos de los fármacos , Factores de Virulencia , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/tratamiento farmacológico , Humanos , Peróxido de Hidrógeno/farmacologíaRESUMEN
The use of antimicrobial drugs in food-producing animals contributes to the selection pressure on pathogenic and commensal bacteria to become resistant. This study aims to evaluate the existence of trade-offs between treatment effectiveness, cost, and the dynamics of resistance in gut commensal bacteria. We developed a within-host ordinary differential equation model to track the dynamics of antimicrobial drug concentrations and bacterial populations in the site of infection (lung) and the gut. The model was parameterized to represent enrofloxacin treatment for bovine respiratory disease (BRD) caused by Pastereulla multocida in cattle. Three approved enrofloxacin dosing regimens were compared for their effects on resistance on P. multocida and commensal E. coli: 12.5 mg/kg and 7.5 mg/kg as a single dose, and 5 mg/kg as three doses. Additionally, we explored non-FDA-approved regimes. Our results indicated that both 12.5 mg/kg and 7.5 mg/kg as a single dose scenario increased the most the treatment costs and prevalence of P. multocida resistance in the lungs, while 5 mg/kg as three doses increased resistance in commensal E. coli bacteria in the gut the most out of the approved scenarios. A proposed non-FDA-approved scenario (7.5 mg/kg, two doses 24 h apart) showed low economic costs, minimal P. multocida, and moderate effects on resistant E. coli. Overall, the scenarios that decrease P. multocida, including resistant P. multocida did not coincide with those that decrease resistant E. coli the most, suggesting a trade-off between both outcomes. The sensitivity analysis suggests that bacterial populations were the most sensitive to drug conversion factors into plasma ( ß ), elimination of the drug from the colon ( Ï ), fifty percent sensitive bacteria (P. multocida) killing effect ( L s50 ), fifty percent of bacteria (E. coli) above ECOFF killing effect ( C r50 ), and net drug transfer rate in the lung ( γ ) parameters.
Asunto(s)
Antibacterianos , Farmacorresistencia Bacteriana , Enrofloxacina , Escherichia coli , Animales , Enrofloxacina/farmacología , Enrofloxacina/administración & dosificación , Enrofloxacina/uso terapéutico , Bovinos , Antibacterianos/farmacología , Antibacterianos/administración & dosificación , Farmacorresistencia Bacteriana/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Pasteurella multocida/efectos de los fármacos , Enfermedades de los Bovinos/tratamiento farmacológico , Enfermedades de los Bovinos/microbiología , Pruebas de Sensibilidad Microbiana , Resultado del Tratamiento , Pulmón/microbiología , Pulmón/efectos de los fármacosRESUMEN
BACKGROUND: Nosocomial infections are a global problem in hospitals all around the world. It is considered a major health problem, especially in developing countries. The increase in the patient's stay in hospitals has increased the mortality rate, and consequently, the costs drastically increase. The main purpose of using disinfectants in the hospital environment is to reduce the risk of nosocomial infections. Ethylene diamine tetra acetic acid (EDTA) causes lysis and increases susceptibility to antimicrobial agents in the planktonic form of bacteria. This substance affects the permeability of the outer membrane of bacteria. It also prevents the formation of biofilms by bacteria. MATERIALS AND METHODS: In the current study, 120 isolates of Acinetobacter baumannii (A. baumannii) were confirmed by phenotypic and genotypic methods. Antibiogram was performed and then the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of isolates against 5% sodium hypochlorite, ethanol %70, sayasept-HP 2%, chlorhexidine 2%, dettol 4/8% were evaluated. In addition, the disinfectant effect was re-evaluated with the mixture of EDTA solution. All isolates were examined for biofilm presence by crystal violet staining method in triplicates and repeated three times for each strain. Also for all isolates detection of efflux pump genes (Qac-E, qacE-Δ1, SUG-E) by PCR technique was done. RESULTS: Antibiogram results of A. baumannii showed that 6.7% were Multi-drug-resistant (MDR), and 89.2% were Extensively drug-resistant (XDR) isolates. The highest effect of disinfectants was related to 5% sodium hypochlorite, and the least effect was 70% ethanol. EDTA increases the efficacy of selected disinfectants significantly. The highest prevalence of the efflux pump genes was related to SUG-E (95%) and Qac-E (91.7%), and, the qacE-Δ1 gene with 12.5%. The biofilm production rate was 91.3% among all isolates. CONCLUSION: The best and safest way to disinfect hospital floors and surfaces is to choose the right disinfectants, and learn how to use them properly. In this study, a mixture of disinfectants and EDTA had a significant effect on bactericidal activity. it was found that improper use of disinfectants, especially the use of sub-inhibitory dilutions, increases the resistance of bacteria to disinfectants.
Asunto(s)
Acinetobacter baumannii , Biopelículas , Desinfectantes , Genotipo , Pruebas de Sensibilidad Microbiana , Fenotipo , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Acinetobacter baumannii/efectos de los fármacos , Acinetobacter baumannii/genética , Acinetobacter baumannii/fisiología , Acinetobacter baumannii/aislamiento & purificación , Desinfectantes/farmacología , Humanos , Irán , Ácido Edético/farmacología , Farmacorresistencia Bacteriana/genética , Antibacterianos/farmacología , Infecciones por Acinetobacter/microbiología , Hipoclorito de Sodio/farmacología , Infección Hospitalaria/microbiología , Clorhexidina/farmacologíaRESUMEN
Colistin resistance testing methods such as broth microdilution (BMD) are time-consuming and labour intensive for clinical laboratories. MBT Lipid Xtract Kit on MALDI Biotyper Sirius System (Bruker, Billerica, MA, USA) utilizes lipidomic analysis to identify specific cell wall modifications associated with colistin resistance. We compared MBT to BMD (ComASP Colistin, Liofilchem) across 36 Gram-negative isolates (non-resistant MIC ≤2 µg ml-1, resistant MIC ≥4 µg ml-1). All samples were tested twice on MBT with discrepant results repeated before assessing categorical agreement between MBT and BMD. 44.4% (16/36) of isolates were colistin resistant via BMD. MBT Lipid Xtract had 80.6% agreement (29/36) with BMD, with 5/7 discrepancies corrected to match upon repeat testing. There was 100% agreement for Escherichia coli isolates (n=16). The whole-genome sequencing was completed on the two discrepant Klebsiella pneumoniae isolates, with variants within colistin resistance-associated loci identified (MIC 0.5 µg ml-1: arnC S30T, pmrB T246A, lapB N212T, lpxM S253G, crrB Q287K and MIC >16 µg ml-1: arnC S30T, pmrB R90insRN, pmrB T246A, pmrA E57G, lpxM S253G). Further evaluation, particularly for non-E. coli, of MBT is required prior to implementation in clinical laboratories.
Asunto(s)
Antibacterianos , Colistina , Farmacorresistencia Bacteriana , Pruebas de Sensibilidad Microbiana , Colistina/farmacología , Antibacterianos/farmacología , Humanos , Bacterias Gramnegativas/efectos de los fármacos , Secuenciación Completa del Genoma , Escherichia coli/efectos de los fármacos , Escherichia coli/genéticaRESUMEN
Solution blowing process was used to prepare cellulose nonwovens, by using N-methyl morpholine-N-oxide (NMMO) as solvent, and salicylic acid (SA) microcapsules as antibacterial additives. The structure and properties of cellulose nonwovens modified with different SA microcapsules contents were compared and evaluated. The results showed that more uniform and denser web structure was formed with the increase of SA microcapsules content, the average fiber diameter of cellulose nonwoven increased from 1.99 µm to 2.65 µm. The air flow resistance and filtration efficiency of cellulose nonwovens increased with addition of SA microcapsules, whereas the mechanical properties, and wearing comfort including air permeability, moisture vapor transfer rate, and softness of cellulose nonwovens decreased slightly, under the same basis weight. SA microcapsules modified cellulose nonwovens exhibited good sustained-release behavior and antimicrobial activity against Escherichia coli. The higher SA microcapsules content in cellulose nonwovens, the faster release rate and the higher antimicrobial activity. The cellulose solution-blown nonwovens modified with SA microcapsules are expected to find applications in medical and healthcare fields due to its antibacterial activity and biodegradability.