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Antimicrobial agents are safe preservatives having the ability to protect foods from microbial spoilage and extend their shelf life. Many factors, including antimicrobials’ chemical features, storage environments, delivery methods, and diffusion in foods, can affect their antimicrobial activities. The physical-chemical characteristics of the food itself play an important role in determining the efficacy of antimicrobial agents in foods; however the mechanisms behind it have not been fully explored. This review provides new insights and comprehensive knowledge regarding the impacts of the food matrix, including the food components and food (micro)structures, on the activities of antimicrobial agents. Studies of the last 10 years regarding the influences of the food structure on the effects of antimicrobial agents against the microorganisms’ growth were summarized. The mechanisms underpinning the loss of the antimicrobial agents’ activity in foods are proposed. Finally, some strategies/technologies to improve the protection of antimicrobial agents in specific food categories are discussed.

Objective: Antibiotic misuse is a significant public health problem worldwide. Parents’ perceptions of antibiotics are critical for the antibiotic intake of children. The study’s aim was to validate the Turkish Parental Perception on Antibiotics Scale. Methods: This is a scale validation study. The data were collected through a questionnaire that consisted of 15 questions about the demographic and socioeconomic characteristics of the family and the Turkish Parental Perception on Antibiotics Scale. The scale, developed by Alumran et al., is a 5-point Likert type and consists of 31 items. The high scores obtained from the non-cut-off scale indicate better antibiotics perception. Experts completed the language adaption and content validity of the scale. Confirmatory factor analysis was used for construct validity. Reliability was tested by internal consistency coefficients. Results: One thousand eight people participated in the study. 68.8% of the participants were mothers. The mean age of the mothers was 35.7±5.0, and the mean age of the fathers was 39.4±5.2 years. The percent of high school and above graduates was 51.2% among mothers and 56.0% among fathers. According to the confirmatory factor analysis, the fit index values were standardized root mean square residual (SRMR)=0.06, goodness-of-fit index (GFI)=0.90, root mean square error of approximation (RMSEA)=0.06, comparative fit index (CFI)=0.95, non-normed fit index (NNFI)=0.93. The fit index values were good or excellent and confirmed the 5-factor structure. It was found that the internal consistency coefficients calculated for reliability were 0.79 for the whole scale and ranged between 0.63 and 0.86 for the subscales. Conclusion: The Turkish Parental Perception on Antibiotics Scale is a valid and reliable measurement tool. Further research is needed to determine the current situation regarding antibiotic perception. © 2023, DOC Design and Informatics Co. Ltd. All rights reserved.

Membrane-enveloped viruses are responsible for most viral pandemics in history, and more effort is needed to advance broadly applicable countermeasures to mitigate the impact of future outbreaks. In this Perspective, we discuss how biosensing techniques associated with lipid model membrane platforms are contributing to improving our mechanistic knowledge of membrane fusion and destabilization that is closely linked to viral entry as well as vaccine and antiviral drug development. A key benefit of these platforms is the simplicity of interpreting the results which can be complemented by other techniques to decipher more complicated biological observations and evaluate the biophysical functionalities that can be correlated to biological activities. Then, we introduce exciting application examples of membrane-targeting antivirals that have been refined over time and will continue to improve based on biophysical insights. Two ways to abrogate the function of viral membranes are introduced here: (1) selective disruption of the viral membrane structure and (2) alteration of the membrane component. While both methods are suitable for broadly useful antivirals, the latter also has the potential to produce an inactivated vaccine. Collectively, we emphasize how biosensing tools based on membrane interfacial science can provide valuable information that could be translated into biomedicines and improve their selectivity and performance. Ministry of Education (MOE) This work was supported by the Ministry of Education (MOE) in Singapore under grant RG111/20 and by a sponsored research agreement from LUCA AICell Inc. (RCA-LUCA AICell REQ0239282).

Tuberculosis (TB) is the leading infectious disease caused by Mycobacterium tuberculosis (Mtb). Clarithromycin (CTY), an analog of erythromycin (ERY), is more potent against multidrug-resistance (MDR) TB. ERY and CTY were previously reported to bind to the nascent polypeptide exit tunnel (NPET) near peptidyl transferase center (PTC), but the only available CTY structure in complex with D. radiodurans (Dra) ribosome could be misinterpreted due to resolution limitation. To date, the mechanism of specificity and efficacy of CTY for Mtb remains elusive since the Mtb ribosome-CTY complex structure is still unknown. Here, we employed new sample preparation methods and solved the Mtb ribosome-CTY complex structure at 3.3�� with cryo-EM technique, where the crucial gate site A2062 (E. coli numbering) is located at the CTY binding site within NPET. Two alternative conformations of A2062, a novel syn-conformation as well as a swayed conformation bound with water molecule at interface, may play a role in coordinating the binding of specific drug molecules. The previously overlooked C���H hydrogen bond (H-bond) and �� interaction may collectively contribute to the enhanced binding affinity. Together, our structure data provide a structural basis for the dynamic binding as well as the specificity of CTY and explain of how a single methyl group in CTY improves its potency, which provides new evidence to reveal previously unclear mechanism of translational modulation for future drug design and anti-TB therapy. Furthermore, our sample preparation method may facilitate drug discovery based on the complexes with low water solubility drugs by cryo-EM technique.

Emerging studies indicate that infusion of HIV-resistant cells could be an effective strategy to achieve a sterilizing or functional cure. We recently reported that glycosylphosphatidylinositol (GPI)-anchored nanobody or a fusion inhibitory peptide can render modified cells resistant to HIV-1 infection. In this study, we comprehensively characterized a panel of newly isolated HIV-1-neutralizing antibodies as GPI-anchored inhibitors. Fusion genes encoding the single-chain variable fragment (scFv) of 3BNC117, N6, PGT126, PGT128, 10E8, or 35O22 were constructed with a self-inactivating lentiviral vector, and they were efficiently expressed in the lipid raft sites of target cell membrane without affecting the expression of HIV-1 receptors (CD4, CCR5 and CXCR4). Significantly, transduced cells exhibited various degrees of resistance to cell-free HIV-1 infection and cell-associated HIV-1 transmission, as well as viral Env-mediated cell–cell fusion, with the cells modified by GPI-10E8 showing the most potent and broad anti-HIV activity. In mechanism, GPI-10E8 also interfered with the processing of viral Env in transduced cells and attenuated the infectivity of progeny viruses. By genetically linking 10E8 with a fusion inhibitor peptide, we subsequently designed a group of eight bifunctional constructs as cell membrane-based inhibitors, designated CMI01∼CMI08, which rendered cells completely resistant to HIV-1, HIV-2, and simian immunodeficiency virus (SIV). In human CD4+ T cells, GPI-10E8 and its bifunctional derivatives blocked both CCR5- and CXCR4-tropic HIV-1 isolates efficiently, and the modified cells displayed robust survival selection under HIV-1 infection. Therefore, our studies provide new strategies for generating HIV-resistant cells, which can be used alone or with other gene therapy approaches.

Bioactive restorative materials are being developed to either influence the de/remineralization balance of the dental hard tissues locally or to release components that interact with the oral microbiota. Surface prereacted glass (S-PRG, Shofu, Japan) is a material that may influence both processes. S-PRG releases fluoride, which can interact with the de/remineralization process, and a range of other compounds that may influence the oral microbiota. In the current study, several experiments were performed to investigate the potential of S-PRG to influence both the growth and lactic acid production of saliva-derived polymicrobial biofilms. Biofilm formation was studied using the Amsterdam Active Attachment model. An eluate of the S-PRG particles was tested by adding it to the growth medium or by exposing the biofilms to it for 1 h. The effect of S-PRG particles was tested by adding the particles to the growth medium. The current experiments showed that the presence of S-PRG eluate in the medium influenced biofilm growth and lactic acid production even at low concentrations. The composition of the biofilms changed in the presence of S-PRG eluate, even at concentrations of S-PRG eluate at which biofilm viability was not affected. Treatment of developing biofilms with S-PRG eluate did neither show an effect on biofilm viability nor on lactic acid production. The addition of S-PRG particles to the growth medium resulted in both a lower biofilm viability and lower lactic acid production, indicating that the release of ions from the particles was fast enough to influence biofilm formation. From the current experiments, it can be concluded that S-PRG has the potential to influence biofilm growth, but the presence of the released ions during biofilm formation is required to show an effect.

This study examined five species of the Lamiaceae family, Origanum vulgare L., Origanum dictamnus L., Origanum majorana L., Mentha spicata L. and Lavandula angustifolia L., and one species of the Hypericaceae family, Hypericum perforatum L., for their potential to enhance health and wellbeing or to prevent diseases. An analysis of secondary metabolites was performed by mass spectrometry and HPLC coupled with diode array detection to determine the phenolic compounds included in the plant extracts. The samples were evaluated for their total phenolic content, antioxidant potential, ability to prevent DNA scission caused by peroxyl radicals and antimicrobial activity against pathogens (MIC). All the samples, except Lavandula angustifolia L., had a high DPPH radical scavenging activity and showed significant antibacterial activity. Origanum majorana L. demonstrated the lowest IC50 value (10.31 μg·mL−1). Extracts of medicinal herbs had a remarkably high phenolic content varying between 428 and 1512.74 μg GAE/mg of dry extract, with Origanum vulgare L. having the largest amount of polyphenols. Moreover, the plant extracts exhibited a high level of resistance against DNA damage, with Origanum majorana L. showing the greatest level of protection with 98.05% inhibition. According to the results of this study, these plants from the Greek flora provide beneficial effects for health as natural antioxidants. A baseline can be established through the analysis of the findings of this survey for future research on the same plant species.

Nucleoside analogs are frequently used in the control of viral infections and neoplastic diseases. However, relatively few studies have shown that nucleoside analogs have antibacterial and antifungal activities. In this study, a fused pyrimidine molecule, uridine, was modified with various aliphatic chains and aromatic groups to produce new derivatives as antimicrobial agents. All newly synthesized uridine derivatives were analyzed by spectral (NMR, FTIR, mass spectrometry), elemental, and physicochemical analyses. Prediction of activity spectra for substances (PASS) and in vitro biological evaluation against bacteria and fungi indicated promising antimicrobial capability of these uridine derivatives. The tested compounds were more effective against fungal phytopathogens than bacterial strains, as determined by their in vitro antimicrobial activity. Cytotoxicity testing indicated that the compounds were less toxic. In addition, antiproliferative activity against Ehrlich ascites carcinoma (EAC) cells was investigated, and compound 6 (2′,3′-di-O-cinnamoyl-5′-O-palmitoyluridine) demonstrated promising anticancer activity. Their molecular docking against Escherichia coli (1RXF) and Salmonella typhi (3000) revealed notable binding affinities and nonbonding interactions in support of this finding. Stable conformation and binding patterns/energy were found in a stimulating 400 ns molecular dynamics (MD) simulation. Structure–activity relationship (SAR) investigation indicated that acyl chains, CH3(CH2)10CO-, (C6H5)3C-, and C2H5C6H4CO-, combined with deoxyribose, were most effective against the tested bacterial and fungal pathogens. Pharmacokinetic predictions were examined to determine their ADMET characteristics, and the results in silico were intriguing. Finally, the synthesized uridine derivatives demonstrated increased medicinal activity and high potential for future antimicrobial/anticancer agent(s).

Background: Ventilator-associated pneumonia (VAP) is a common and genuine complication in fundamentally sick patients accepting mechanical ventilation. Silver nitrate sol-gel (SN) has been proposed as a potential preventative measure against VAP. Be that as it may, the arrangement of SN with distinctive concentrations and pH values remains a basic factor influencing its effectiveness. Methods: Silver nitrate sol-gel was arranged with distinctive concentrations (0.1852%, 0.03496%, 0.1852%, and 0.01968%) and pH values (8.5, 7.0, 8.0, and 5.0) separately. The antimicrobial action of the silver nitrate and NaOH arrangements were assessed against Escherichia coli as a reference strain. The thickness and pH of the arrangements were measured, and biocompatibility tests were performed on the coating tube. The auxiliary changes in the endotracheal tube (ETT) tests after treatment were analyzed utilizing electron microscopy (SEM) and transmission electron microscopy (TEM). Results: The pH estimations of the diverse arrangements showed that the pH values shifted depending on the test conditions, with pH values extending from 5.0 to 8.5. The consistency estimations of the arrangements showed that the thickness values expanded as the pH values drew closer to 7.5 and diminished when the pH values went over 7.5. The antimicrobial action of the silver nitrate and NaOH arrangements were successful against Escherichia coli, with microbial checks decreasing in concentration (0.03496%, 0.1852% (pH: 8), and 0.01968%). The biocompatibility tests revealed tall cell reasonability rates, demonstrating that the coating tube was secure for therapeutic utilization and did not hurt typical cells. The SEM and TEM investigation gave visual proof of the antibacterial impacts of the silver nitrate and NaOH arrangements on the bacterial surface or interior of the bacterial cells. Moreover, the investigation revealed that a concentration of 0.03496% was the foremost successful in hindering the development of ETT bacterial colonization at the nanoscale level. Conclusions: We propose that cautious control and alteration of the pH and thickness of the arrangements are essential to guaranteeing the reproducibility and quality of the sol-gel materials. The silver nitrate and NaOH arrangements may serve as a potential preventative degree against VAP in sick patients, with a concentration of 0.03496% appearing to show the most elevated viability. The coating tube may serve as a secure and viable preventative measure against VAP in sick patients. Further investigation is required to optimize the concentration and introduction time of the arrangements to maximize their adequacy in avoiding VAP in real-world clinical settings.

This study investigated the inhibitory activity of organic solutions containing 5, 10, 15, 20 and 30% (w/v) sodium chloride and citric acid solution and 15:10, 15:15, 15:20 and 15:30% (w/v) sodium chloride (NaCl) combined with citric acid (CA) solution (salt/acid solution) for 10 min against microorganisms isolated from trimmed young coconut: Bacillus cereus, B. subtilis, Staphylococcus aureus, S. epidermidis, Enterobacter aerogenes, Serratia marcescens, Candida tropicalis, Lodderromyces elongisporus, Aspergillus aculeatus and Penicillium citrinum. Commercial antimicrobial agents such as potassium metabisulfite and sodium hypochlorite (NaOCl) were used as the controls. Results showed that 30% (w/v) NaCl solution displayed antimicrobial properties against all microorganisms, with s reduction range of 0.00–1.49 log CFU/mL. Treatment of 30% (w/v) CA solution inhibited all microorganisms in the reduction range of 1.50–8.43 log CFU/mL, while 15:20% (w/v) salt/acid solution was the minimum concentration that showed a similar antimicrobial effect with NaOCl and strong antimicrobial effect against Gram-negative bacteria. The mode of action of this solution against selected strains including B. cereus, E. aerogenes and C. tropicalis was also determined by scanning electron microscopy and transmission electron microscopy. B. cereus and E. aerogenes revealed degradation and detachment of the outer layer of the cell wall and cytoplasm membrane, while cytoplasmic inclusion in treated C. tropicalis cells changed to larger vacuoles and rough cell walls. The results suggested that a 15:20% (w/v) salt/acid solution could be used as an alternative antimicrobial agent to eliminate microorganisms on fresh produce.

Essential oils possessing antimicrobial characteristics have acquired considerable interest as an alternative to chemical preservatives in food products. This research hypothesizes that mānuka (MO) and kānuka (KO) oils may possess antimicrobial characteristics and have the potential to be used as natural preservatives for food applications. Initial experimentation was conducted to characterize MOs (with 5, 25, and 40% triketone contents), rosemary oil (RO) along with kanuka oil (KO) for their antibacterial efficacy against selected Gram-negative (Salmonella spp. and Escherichia coli), and Gram-positive (Listeria monocytogenes and Staphylococcus aureus) bacteria through disc diffusion and broth dilution assays. All MOs showed a higher antimicrobial effect against L. monocytogenes and S. aureus with a minimum inhibitory concentration below 0.04%, compared with KO (0.63%) and RO (2.5%). In chemical composition, α-pinene in KO, 1, 8 cineole in RO, calamenene, and leptospermone in MO were the major compounds, confirmed through Gas-chromatography-mass spectrometry analysis. Further, the antimicrobial effect of MO and RO in vacuum-packed beef pastes prepared from New Zealand commercial breed (3% fat) and wagyu (12% fat) beef tenderloins during 16 days of refrigerated storage was compared with sodium nitrate (SN) and control (without added oil). In both meat types, compared with the SN-treated and control samples, lower growth of L. monocytogenes and S. aureus in MO- and RO- treated samples was observed. However, for Salmonella and E. coli, RO treatment inhibited microbial growth most effectively. The results suggest the potential use of MO as a partial replacement for synthetic preservatives like sodium nitrate in meats, especially against L. monocytogenes and S. aureus.

Background: The susceptibility to SARS-CoV-2 infection is complex and not yet fully elucidated, being related to many variables; these include human microbiome and immune status, which are both affected for a long period by antibiotic use. We therefore aimed to examine the association of previous antibiotic consumption and SARS-CoV-2 infection in a large-scale population-based study with control of known confounders. Methods: A matched case–control study was performed utilizing the electronic medical records of a large Health Maintenance Organization. Cases were subjects with confirmed SARS-CoV-2 infection (n = 31,260), matched individually (1:4 ratio) to controls without a positive SARS-CoV-2 test (n = 125,039). The possible association between previous antibiotic use and SARS-CoV-2 infection was determined by comparing antibiotic consumption in the previous 6 and 12 months between the cases and controls. For each antibiotic consumed we calculated the odds ratio (OR) for documented SARS-CoV-2 infection, 95% confidence interval (CI), and p-value using univariate and multivariate analyses. Results: The association between previous antibiotic consumption and SARS-CoV-2 infection was complex and bi-directional. In the multivariate analysis, phenoxymethylpenicillin was associated with increased rate of SARS-CoV-2 infection (OR 1.110, 95% CI: 1.036–1.191) while decreased rates were associated with previous consumption of trimethoprim-sulfonamides (OR 0.783, 95% CI: 0.632–0.971) and azithromycin (OR 0.882, 95% CI: 0.829–0.938). Fluroquinolones were associated with decreased rates (OR 0.923, 95% CI: 0.861–0.989) only in the univariate analysis. Previous consumption of other antibiotics had no significant association with SARS-CoV-2 infection. Conclusions: Previous consumption of certain antibiotic agents has an independent significant association with increased or decreased rates of SARS-CoV-2 infection. Plausible mechanisms, that should be further elucidated, are mainly antibiotic effects on the human microbiome and immune modulation.

Enterococci are regarded as a better indication of faecal pollution in freshwater and marine waters. Their levels in seawater are positively connected with swimming-related gastrointestinal disorders. This study used an Enterococcus-specific polymerase chain reaction (PCR) to characterize the isolates. Classes 1 and 2 integrons were examined for environmental Enterococcus isolates using a standard biological procedure. All strains were assessed against a panel of 12 antibiotics from various classes using disc diffusion methods. The microdilution method was used to work out the minimum inhibitory concentration (MIC) according to the CLSI guiding principles. The combination therapy of the resistant drugs was evaluated using a checkerboard assay and a time-dependent test for assessing their bactericidal or bacteriostatic activity. The gene diversity of the tested organisms was analyzed with the aid of Enterobacterial Repetitive Intergenic Consensus (ERIC) PCR. In total, 57 Enterococcus spp. environmental samples were recovered, in which Enterococcus faecalis (33.33%) and Enterococcus faecium (59.65%) were the dominant species. Resistance to linezolid, ciprofloxacin, erythromycin, gentamicin, vancomycin, rifampicin, and tetracycline was prevalent. Fifty (50) strains tested positive for class 1 integron, more frequent in Enterococcus faecium and Enterococcus faecalis isolates, with no gene cassette array discovered. A combination of gentamicin (MIC 4 µg/mL) with vancomycin (MIC 256 µg/mL) antibiotics against Enterococcus faecalis showed antibacterial activity. In contrast, the combination of ciprofloxacin (1 µg/mL) with Ampicillin (16 µg/mL) antibiotics against Enterococcus faecalis showed a bacteriostatic effect. The ERIC-PCR analysis pointed out that most of the assessed isolates have close genetic similarities.

Bacteria may be the initial cause of certain pathologies as well as a secondary agent responsible for the development of complications such as pressure ulcer infections. Pressure ulcers are a persistent health problem, especially in immunocompromised patients, and associated with infection by opportunistic microorganisms with antimicrobial resistance, such as Klebsiella pneumoniae, highlight the need for the development of new antimicrobial approaches. Thus, the aim of this study was to evaluate the antibacterial and anti-adherent activity of Origanum vulgare L. (oregano) essential oil against Klebsiella pneumoniae strains, as well as the effect of its association with synthetic antimicrobials. To this end, the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) analyses were performed on microdilution plates. The assay of the Minimum Inhibitory Adherence Concentration (MIAC), with test tubes. As well as, the association study through the infusion disc method containing ampicillin (AMP), gentamicin (GEN), ciprofloxacin (CIP) and ceftriaxone (CEF). Therefore, it was possible to obtain that the essential oil of oregano presents antimicrobial and bactericidal activity, with MIC ranging between 128μg/mL and 256 μg/mL and MBC between 256 μg/mL and 512 μg/mL, on the tested K. pneumoniae strains. When used in association with ampicillin and gentamicin, oregano essential oil showed synergistic effect for some strains. Therefore, it is observed that the tested essential oil can act as a promising antibacterial in the treatment of diseases caused by K. pneumoniae. Resumo As bactérias podem ser a causa inicial de determinadas patologias como também um agente secundário responsável pelo desenvolvimento de complicações como as infecções das lesões por pressão. As lesões por pressão configuram um problema de saúde persistente, principalmente em pacientes imunocomprometidos, e associadas a infecção por microrganismos oportunistas com resistência antimicrobiana, como por exemplo a Klebisiella pneumoniae, ressaltam a necessidade do desenvolvimento de novas abordagens antimicrobianas. Assim, o objetivo deste estudo foi avaliar a atividade antibacteriana e antiaderente do óleo essencial de Origanum vulgareL. (orégano) contra cepas da Klebisiella pneumoniae, bem como o efeito da sua associação com antimicrobianos sintéticos. Para isso foram realizadas as análises da Concentração Mínima Inibitória (CIM) e Concentração Bactericida Mínima (CBM) em placas de micro diluição. O ensaio da Concentração Mínima de Aderência (CIMA), com tubos de ensaio. Como também, o estudo de associação através do método de disco de infusão contendo ampicilina, gentamicina, ciprofloxacino e ceftriaxona. Assim sendo, foi possível obter que o óleo essencial de orégano apresenta atividade antimicrobiana e bactericida, com CIM variando entre 128μg/mL e 256 μg/mL e CBM entre 256 μg/mL e 512 μg/mL, sobre as cepas de K. pneumoniae testadas. Quando utilizado em associação com a ampicilina e gentamicina, o óleo essencial de orégano demonstrou efeito sinérgico para algumas cepas. Portanto, observa-se que o óleo essencial testado pode atuar como um promissor antibacteriano no tratamento de doenças causadas por K. pneumoniae.

Funding Information: This study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior – Brazil (CAPES) – Finance Code 001. Publisher Copyright: Copyright © 2023 Schneider, Vieira, Carvalho, Sousa, Watanabe, Andrade and Silveira. Background: Antimicrobial textiles have proved to be a promising biosafety strategy. Thus, the current study was focused on identifying which antimicrobial substances impregnated in textiles used in healthcare services confer efficacy in reducing the microbial load present in these textiles and/or the Healthcare-Associated Infection (HAI) rates, when compared to conventional textiles. Methods: A systematic review of intervention studies using MEDLINE via the PubMed portal, EMBASE, CINAHL, Web of Science, Scopus, Google Scholar and medRxiv. The studies identified were selected according to eligibility criteria and submitted to data extraction and methodological quality evaluation through Joanna Briggs Institute specific tools. The outcomes were synthesized qualitatively. Results: 23 studies were selected to comprise the final sample, in which antimicrobial textiles were used by hospitalized patients, by health professionals during work shifts and in inanimate healthcare environments. Conclusions: Copper, silver, zinc oxide, titanium and silver-doped titanium impregnated in textiles used by patients confer efficacy in reducing the microbial load of these textiles and/or the HAI rates. Quaternary ammonium, chlorhexidine, silver and copper together, quaternary ammonium, alcohols and isothiazolone derivatives together, chitosan and dimethylol dimethyl hydantoin together, all impregnated in textiles used by health professionals confer efficacy in reducing the microbial load of these textiles. Quaternary ammonium impregnated in textiles used in inanimate healthcare environments confers efficacy in reducing the microbial load of these textiles. publishersversion published

One of the biggest challenges faced by the meat industry is maintaining the freshness of meat while extending its shelf life. Advanced packaging systems and food preservation techniques are highly beneficial in this regard. However, the energy crisis and environmental pollution demand an economically feasible and environmentally sustainable preservation method. Emulsion coatings (ECs) are highly trending in the food packaging industry. Efficiently developed coatings can preserve food, increase nutritional composition, and control antioxidants' release simultaneously. However, their construction has many challenges, especially for meat. Therefore, the following review focuses on the essential aspects of developing ECs for meat. The study begins by classifying emulsions based on composition and particle size, followed by a discussion on the physical properties, such as ingredient separation, rheology, and thermal characteristics. Furthermore, it discusses the lipid and protein oxidation and antimicrobial characteristics of ECs, which are necessary for other aspects to be relevant. Lastly, the review presents the limitations of the literature while discussing the future trends. ECs fabricated with antimicrobial/antioxidant properties present promising results in increasing the shelf life of meat while preserving its sensory aspects. In general, ECs are highly sustainable and effective packaging systems for meat industries., Tomas Bata University in Zlin, TBU: IGA/FT/2023/007; Univerzita Palackého v Olomouci: IGA_PrF_2023_024, Tomas Bata University in Zlin [IGA/FT/2023/007]; Palacky University in Olomouc [IGA_PrF_2023_024]

Vajira Medical Journal: Journal of Urban Medicine, 67, 3, none

Aim: The antimicrobial cetylpyridinium chloride (CPC) is used in the management of denture stomatitisassociated oral candidiasis as an alternative therapy as well as for oral hygiene. Cetylpyridinium chloride survives in the oral cavity for long periods at low doses, which fluctuates due to the dynamics of the oral cavity. In this study, it was aimed to evaluate the impact of different sub-therapeutic CPC concentrations (1/100, 1/200) for different time periods (0.,5., 2., 24., 48. h) on the expression of drug-resistance genes (CDR1, CDR2, MDR1, ERG11) in Candida albicans SC5314. Method: Total RNA was extracted immediately after antimicrobial exposure using the Biospeedy® TriEasy Isolation Kit followed by Real-Time Quantitative Reverse Transcription polymerase chain reaction (qRT-PCR). The data were analyzed by the comparative 2-ΔΔCT method to calculate the relative expression of the target genes after treatment with different CPC concentrations, standardized to the housekeeping gene Actin. Results: In this study, it was found that the drug resistance gene expression levels increased after exposure to high CPC concentrations (1/100) for 48 h, whereas the gene expression levels were downregulated at 1/200. Conclusion: These results may provide an insight into the mechanisms of action of drug-resistance genes in Candida albicans and aid the development of future strategies for using CPC as an alternative therapy., Amaç: Antimikrobiyal setilpridinyum klorür (CPC), ağız hijyeninin yanı sıra alternatif bir tedavi olarak protez stomatitiyle ilişkili oral kandidiyazis tedavisinde kullanılır. Setilpridinyum klorür (CPC), ağız boşluğunun dinamikleri nedeniyle dilue olarak ağız boşluğunda düşük dozlarda uzun süre mevcut kalır. Bu çalışmada, farklı zaman periyotlarında (0.,5., 2., 24., 48. saat) farklı alt terapötik CPC konsantrasyonlarının (1/100, 1/200) Candida albicans SC5314'te ilaca direnç genlerinin (CDR1, CDR2, MDR1, ERG11) ekspresyonu üzerindeki etkisinin değerlendirilmesi amaçlanmıştır. Yöntem: Toplam RNA, antimikrobiyal ile maruziyetten hemen sonra Biospeedy® Tri-Easy Isolation Kit ve ardından qRT-PCR kullanılarak ekstre edildi. Bu veriler, farklı CPC konsantrasyonları ile muameleden sonra hedef genlerin nispi ekspresyonunu hesaplamak için karşılaştırmalı 2-ΔΔCT yöntemiyle analiz edildi, Aktin housekeeping genine standardize edildi. Bulgular: Bu çalışmada, 48 saat boyunca, yüksek CPC konsantrasyonuna (1/100) maruz kalan örneklerde Candida ilaç direnci gen ekspresyon seviyelerinin arttığı, buna karşın 1/200 konsantrasyonunda bekletildiğinde azaldığı bulundu. Sonuç: Bu sonuçlar, Candida albicans'ta ilaca dirençli genlerin etki mekanizmaları hakkında bir fikir verebilir ve alternatif bir tedavi olarak CPC'yi kullanmak için gelecekteki stratejilerin geliştirilmesine yardımcı olabilir.

Antimicrobial resistance (AMR) and hospital-acquired infections (HAIs) are global health challenges. The burden of antibiotic resistance in HAIs is still unclear in low- and lower-middle-income countries (L-LMICs). This study summarizes recent data on antibiotic resistance in priority HAIs (ESKAPE-E) in L-LMICs and compares them with data from high-income countries (HICs). EMBASE, Web of Science, and Global Index Medicus were searched for studies on AMR patterns in HAIs published from 01/2010 to 10/2020. Random-effects meta-analyses were performed to obtain pooled estimates. In total, 163 eligible studies were included in the review and meta-analysis. The pooled methicillin resistance proportion in Staphylococcus aureus was 48.4% (95% confidence interval [95%CI] 41·7-55·2, n = 80). Pooled carbapenem resistance proportions were high in Gram-negative pathogens: Escherichia coli: 16·6% (95%CI 10·7-23·4, n = 60); Klebsiella pneumoniae: 34·9% (95%CI 24·6-45·9, n = 50); Pseudomonas aeruginosa: 37.1% (95%CI 24·6-45·9, n = 56); Enterobacter spp.: 51·2% (95%CI 27·5-74·7, n = 7); and Acinetobacter baumannii (complex): 72·4% (95%CI 62·1-81·7%, n = 36). A higher resistance proportions were observed for third-generation cephalosporins: Klebsiella pneumoniae: 78·7% (95%CI 71·5-85·2, n = 46); Escherichia coli: 78·5% (95%CI 72·1-84·2%, n = 58); and Enterobacter spp.: 83·5% (95%CI 71·9-92·8, n = 8). We observed a high between-study heterogeneity (I2 > 80%), which could not be explained by our set of moderators. Pooled resistance proportions for Gram-negative pathogens were higher in L-LMICs than regional and national estimates from HICs. Patients in resource-constrained regions are particularly affected by AMR. To combat the high resistance to critical antibiotics in L-LMICs, and bridge disparities in health, it is crucial to strengthen local surveillance and the health systems in general.

Background/aim: Our study investigated the susceptibility rate of ceftazidime-avibactam and the risk factors associated with its resistance by analyzing gram-negative bacteria isolated from various patient samples. Materials and methods: Between March and November 2020, 1119 gram-negative bacteria strains were isolated from patient samples in Acıbadem Healthcare Group hospitals; ceftazidime-avibactam susceptibility results were evaluated using a 10/4µg (Oxoid, UK) disc and evaluated according to Eucast 2020 recommendations. Patient and isolate characteristics that could be risk factors were retrospectively investigated and statistically analyzed using SPSS 25.0. Results: Male patients made up 52% (n = 581) of the study’s total patient population, and they averaged 55.5 ± 24.9 years old. Of 1119 gram-negative strains culture and antibiogram, 1023 (91.4%) were sensitive to ceftazidime-avibactam. An increased risk of resistance was observed with female gender (OR = 2.29; CI 95% [1.45–3.61]; p < 0.05), Pseudomonas aeruginosa (OR = 1.67, CI 95% [1.03–2.7]; p < 0.05), the presence of multidrug-resistance (MDR) (OR = 4.07, CI 95% [2.47–6.7]; p < 0.05) pandrug-resistance (PDR) (OR = 12, (CI) 95% [9.9–14.7] ]; p < 0.05) and admission to intensive care unit (ICU) (OR = 1.89, CI 95% [1.22–2.93]; p < 0.05). Conclusion: The resistance rate of ceftazidime-avibactam was found to be 8.6%, and it was thought that resistant strains produced metallo-ß-lactamase (MBL) type carbapenemase. Risk factors were female gender, Pseudomonas aeruginosa, MDR, PDR, and admission to ICU. Therefore, studying the ceftazidime-avibactam susceptibility test together with gram-negative bacteria identification, especially in groups at risk for resistance, is one of the important factors that can positively affect the success of treatment.

Some transition metals, like manganese, iron, cobalt, nickel, copper and zinc, required for the biosynthesis of metalloenzymes and metalloproteins, are essential micronutrients for the growth and development of pathogenic microorganisms. Among the defenses put in place by the host organism, the so-called “nutritional immunity” consists of reducing the availability of micronutrients and thus “starving” the pathogen. In the case of metals, microorganisms can fight the nutritional immunity in different ways, i.e. by directly recruiting the metal ion or capturing an extracellular metalloprotein or also through the synthesis of specific metallophores which allow importing the metal in the form of a chelate complex. The best known and most studied metallophores are those directed to iron (siderophores), but analogous chelators are also expressed by microorganisms to capture other metals, such as zinc. An efficient zinc recruitment can also be achieved by means of specialized zinc-binding proteins. A deep knowledge of the properties, structure and action mechanisms of extracytoplasmic zinc chelators can be a powerful tool to find out new therapeutic strategies against the antibiotic and/or antifungal resistance. This review aims to collect the knowledge concerning zincophores (small molecules and proteins in charge of zinc acquisition) expressed by bacterial or fungal microorganisms that are pathogenic for the human body.

Črevesne bakterije Campylobacter jejuni so od leta 2005 najpogostejši povzročitelj gastrointestinalnih okužb ljudi v Evropski Uniji. Glavni vir okužb z bakterijami C. jejuni pri ljudeh so uživanje nezadostno obdelanega perutninskega mesa, nepasteriziranega mleka in kontaminirane vode. Tu nastane vprašanje, kako bakterije C. jejuni, ki so poznane kot zelo občutljive na okoljske razmere, vseeno preživijo v okolju in pozvročijo nadaljne kontaminacije hrane in okužbe ljudi. Raziskave v zadnjih letih nakazujejo na sposobnost preživetja bakterij C. jejuni v biofilmih, ki jim omogočijo zaščito pred neugodnimi razmerami v okolju. Predvidevamo, da bi preprečitev pritrditve bakterij C. jejuni na površine, ki je prva stopnja tvorbe biofilma, lahko negativno vplivala na vse nadaljne stopnje tvorbe biofilma. V magistrski nalogi smo ovrednotili vpliv mutacij v genih, vključenih v različne stopnje nastanka biofilma.Vkjlučili smo: (i) šest sevov mutantov bakterij C. jejuni z enojno mutacijo v genih vključenih v različne stopnje nastanka biofilma (sevi mutantov v genih luxS, kpsM, omp50, csrA, rrpA in rrpB) ter (ii) tri seve mutantov bakterij C. jejuni z dvojno mutacijo v genih vključenih v različne stopnje nastanka biofilma (gena luxS in kpsM, gena luxS in omp50, ter gena rrpA in rrpB). Rezultati so pokazali pomembno vlogo posameznih genov, prevsem genov luxS, csrA in omp50, ki torej predstavljajo potencialni tarčni mehanizem alternativnih strategij nazdora nad patogenimi bakterijami C. jejuni. Intestinal bacteria Campylobacter jejuni have been the most common cause of gastrointestinal infections in humans in the European Union since 2005. The main source of C. jejuni infections in humans is the consumption of insufficiently processed poultry meat, unpasteurized milk and contaminated water. This raises the question of how C. jejuni bacteria, which are known to be very sensitive to external environmental conditions, still survive in the environment and cause further food contamination and human infections. Research in recent years indicates the ability of C. jejuni bacteria to survive in biofilms, which enable them to protect themselves from adverse environmental conditions. We hypothesize that preventing the adhesion of C. jejuni bacteria to surfaces, which is the first stage of biofilm formation, could negatively affect all subsequent stages of biofilm formation. In this master's thesis, we evaluated the impact of mutations in genes involved in different stages of biofilm formation. We included: (i) six mutants of bacteria C. jejuni with single mutations in genes involved in different stages of biofilm formation (mutants in genes luxS, kpsM, omp50, csrA, rrpA and rrpB) and (ii) three mutants of bacterial C. jejuni with a double mutation in genes involved in different stages of biofilm formation (luxS and kpsM genes, luxS and omp50 genes, and rrpA and rrpB genes). The results showed an important role of individual genes, especially, genes luxS, csrA and omp50, which therefore represent a potential target mechanism of alternative control strategies over the pathogenic bacteria C. jejuni.

Introduction. Food packaging has played an important and varied role, accordance with the requirements and demands of the market. Currently, these needs are focused on the goal of having safe and innocuous food for as long as possible. To this end, the study and development of new technologies for food packaging has been expanded, which provides the conditions and characteristics necessary to achieve the proposed objective. Objective. To present the most recent advances in the field of food packaging (active and intelligent). Development. This work presents different techniques and criteria that are considered used to propose the concept of active packaging. Gathering the necessary conditions for the supply or suppression of beneficial or harmful substances, contributing to the conservation and deterioration of the contained foods. In some cases, various compounds, mostly of natural origin, are incorporated to counteract the deterioration of food, such as antioxidants, antimicrobials, oxygen absorbers, carbon dioxide, and ethylene. At the same time, the technology known as intelligent packaging is presented, equipped with the necessary resources to monitor and interpret the internal state of the container, and with the ability to communicate this condition visually to be identified by consumers, merchants, and manufacturers. In both cases, the aim is to eliminate or delay the undesirable modification of food and its implications for human health. Conclusions. The generation of active and intelligent packaging represents an important innovation, which manages to increase the shelf life of food, in conditions suitable for consumption. Reaching a considerable economic impact of the sectors involved. These new developments require an individual evaluation of each specific food against the components used. To know the concentrations, according to the characteristic that is required to be controlled, and in this way, understand the possible interactions that can occur between the content and the container that contains it. Resumen Introducción. El envasado de alimentos ha jugado un papel importante y variado, de acuerdo con los requerimientos y demandas del mercado. Actualmente, estas necesidades se centran en el objetivo de tener alimentos seguros e inocuos durante el mayor tiempo posible. Para ello, se ha ampliado el estudio y desarrollo de nuevas tecnologías para el envasado de alimentos, que aportan las condiciones y características necesarias para conseguir el objetivo propuesto. Objetivo. Presentar los avances más recientes en el campo de los envases para alimentos (activos e inteligentes). Desarrollo. Este trabajo presenta diferentes técnicas y criterios que se consideran utilizados para proponer el concepto de envase activo. Reuniendo las condiciones necesarias para el suministro o supresión de sustancias benéficas o dañinas, contribuyendo a la conservación y deterioro de los alimentos contenidos. En algunos casos, se incorporan diversos compuestos, en su mayoría de origen natural, para contrarrestar el deterioro de los alimentos como es el caso de antioxidantes, antimicrobianos, absorbedores de oxígeno, dióxido de carbono y etileno. Además, se presenta la tecnología conocida como embalaje inteligente, dotado de los recursos necesarios para monitorizar e interpretar el estado interno del envase, y con la capacidad de comunicar esta condición de manera visual para ser identificado por los consumidores, comerciante y fabricantes. En ambos casos, se busca eliminar o retardar la modificación indeseada de los alimentos y sus implicaciones sobre la salud humana. Conclusiones. La generación de envases activos e inteligentes representa una importante innovación, que logra incrementar la vida útil de los alimentos, en condiciones aptas para su consumo. Alcanzando un considerable impacto económico de los sectores involucrados. Estos nuevos desarrollos requieren una evaluación individual de cada alimento específico frente a los componentes utilizados. Para conocer las concentraciones, según la característica que se requiera controlar, y de este modo, comprender las posibles interacciones que pueden ocurrir entre el contenido y el recipiente que lo contiene.

Bacterial biofilms are difficult to treat due to their resistance to traditional antibiotics. Although photodynamic therapy (PDT) has made significant progress in biomedical applications, most photosensitizers have poor water solubility and can thus aggregate in hydrophilic environments, leading to the quenching of photosensitizing activity in PDT. Herein, a benzoselenadiazole-containing ligand was designed and synthesized to construct the zirconium (IV)-based benzoselenadiazole-doped metal-organic framework (Se-MOF). Characterizations revealed that Se-MOF is a type of UiO-68 topological framework with regular crystallinity and high porosity. Compared to the MOF without benzoselenadiazole, Se-MOF exhibited a higher 1O2 generation efficacy and could effectively kill Staphylococcus aureus bacteria under visible-light irradiation. Importantly, in vitro biofilm experiments confirmed that Se-MOF could efficiently inhibit the formation of bacteria biofilms upon visible-light exposure. This study provides a promising strategy for developing MOF-based PDT agents, facilitating their transformation into clinical photodynamic antibacterial applications.

The World Health Organization expressed concern that antimicrobial resistance would increase during the COVID-19 pandemic due to the excessive use of antibiotics. This study aimed to explore if antibiotic prescribing patterns in general practices located in the North Denmark Region changed during the COVID-19 pandemic. The study was conducted as a registry-based study. Data was collected for every antibiotic prescription issued in general practices located in the North Denmark Region during the first year of the pandemic (1 February 2020 to 31 January 2021) and the year prior to the pandemic (1 February 2019 to 31 January 2020). Data were compared regarding antibiotic agents and the type of consultation linked to each antibiotic prescription. Results showed that antibiotic prescriptions decreased by 18.5% during the first pandemic year. The use of macrolides and lincosamides, along with combinations of penicillins and beta-lactamase -sensitive penicillins, was reduced the most. Face-to-face consultations related to an antibiotic prescription decreased by 28.5%, while the use of video consultations increased markedly. In Denmark, COVID-19 restrictions have contributed to both a lower consumption of antibiotics and a change in prescription patterns in general practice. Probably some of the COVID-19 -preventing initiatives could be of importance moving forward in the fight against antimicrobial resistance.

Infection prevention clothing is becoming an essential protective tool in the current pandemic, especially because now we know that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can easily infect humans in poorly ventilated indoor spaces. However, commercial infection prevention clothing is made of fabrics that are not capable of inactivating the virus. Therefore, viral infections of symptomatic and asymptomatic individuals wearing protective clothing such as masks can occur through aerosol transmission or by contact with the contaminated surfaces of the masks, which are suspected as an increasing source of highly infectious biological waste. Herein, we report an easy fabrication method of a novel antiviral non-woven fabric containing polymer filaments that were coated with solidified hand soap. This extra protective fabric is capable of inactivating enveloped viruses such as SARS-CoV-2 and phage Φ6 within 1 min of contact. In this study, this antiviral fabric was used to fabricate an antiviral face mask and did not show any cytotoxic effect in human keratinocyte HaCaT cells. Furthermore, this antiviral non-woven fabric could be used for the fabrication of other infection prevention clothing such as caps, scrubs, shirts, trousers, disposable gowns, overalls, hoods, aprons, and shoe covers. Therefore, this low-cost technology could provide a wide range of infection-protective tools to combat COVID-19 and future pandemics in developed and underdeveloped countries.

Herein, a series of novel 1H-1,2,3-triazole and carboxylate derivatives of metronidazole (5a–i and 7a–e) were synthesized and evaluated for their antimicrobial activity in vitro. All the newly synthesized compounds were characterized by 1H NMR, 13C NMR, HRMS, and 19F NMR (5b, 5c and 5h) spectroscopy wherever applicable. The structures of compounds 3, 5c and 7b were unambiguously confirmed by single crystal X-ray analysis diffraction method. Single crystal X-ray structure analysis supported the formation of the metronidazole derivatives. The antimicrobial (antifungal and antibacterial) activity of the prepared compounds was studied. All compounds (except 2 and 3) showed a potent inhibition rate of fungal growth as compared to control and metronidazole. The synthetic compounds also showed higher bacterial growth inhibiting effects compared to the activity of the parent compound. Amongst the tested compounds 5b, 5c, 5e, 7b and 7e displayed excellent potent antimicrobial activity. The current study has demonstrated the usefulness of the 1H-1,2,3-triazole moiety in the metronidazole skeleton.

Aim. To synthesize, study the antimicrobial activity and suggest antimicrobial activity mechanism for the novel derivatives of 6-(1H-benzimidazol-2-yl)-5-methylthieno[2,3-d]pyrimidin-4(3H)-one. Results and discussion. As the result of the targeted modification of 6-(1H-benzimidazol-2-yl)-5-methylthieno[2,3-d]-pyrimidin-4(3H)-one in position 3 with acetamide and 1,2,4-oxadiazol-5-ylmethyl substituents, the compounds, which demonstrated better antimicrobial activity in the agar well diffusion assay than the reference drug Streptomycin, were obtained. To elucidate the mechanism of action of the novel compounds, the docking studies were con-ducted to the active site of the 16S subunit of ribosomal RNA, the proven target for aminoglycoside antibiotics, as well as tRNA (Guanine37-N1)-methyltransferase (TrmD), which inhibitors were considered as a new potential class of antibiotics. Experimental part. By the interaction of 6-(1H-benzimidazol-2-yl)-5-methylthieno[2,3-d]pyrimidin-4(3H)-one with a series of N-arylchloroacetamides and 3-aryl-5-(chloromethyl)-1,2,4-oxadiazoles in DMF in the presence of K2CO3 the target compounds were obtained. The antimicrobial activity was assessed by the agar well diffusion method. The concentration of microbial cells was determined by the McFarland standard; the value was 107 cells in 1 mL of the media. The 18 – 24 hour culture of microorganisms was used for tests. For the bacteria cultivation, Müller-Hinton agar was used, Sabouraud agar was applied for C. albicans cultivation. The compounds were tested as the DMSO solution with the concentration of 100 µg/mL; the volume of the solution was 0.3 mL, the same volume was used for Streptomycin (the concentration 30 µg/mL). The docking studies were performed using Autodock Vina. Crystallographic data for the complexes of Streptomycin with the 16S subunit of ribosomal RNA (1NTB) and its active site, as well as for tRNA (Guanine37-N1)-methyltransferase (EC 2.1.1.228; TrmD) (5ZHN) and its active site were obtained from the Protein Data Bank.Conclusions. It has been determined that 2-[6-(1H-benzimidazol-2-yl)-5-methyl-4-oxothieno[2,3-d]pyrimidin-3(4H)-yl]-N-[4-(ethoxy)phenyl]acetamide, which is the most active as an antimicrobial agent among the compounds tested, also shows the best binding activity towards the active site of tRNA (guanine37-N1)-methyltransferase.

The recovery of other pathogens in patients with SARS-CoV-2 infection has been reported, either at the time of a SARS-CoV-2 infection diagnosis (co-infection) or subsequently (superinfection). However, data on the prevalence, microbiology, and outcomes of co-infection and superinfection are limited. The purpose of this study was to examine the occurrence of co-infections and superinfections and their outcomes among patients with SARS-CoV-2 infection.We searched literature databases for studies published from October 1, 2019, through February 8, 2021. We included studies that reported clinical features and outcomes of co-infection or superinfection of SARS-CoV-2 and other pathogens in hospitalized and non-hospitalized patients. We followed PRISMA guidelines, and we registered the protocol with PROSPERO as: CRD42020189763.Of 6639 articles screened, 118 were included in the random effects meta-analysis. The pooled prevalence of co-infection was 19% (95% confidence interval [CI]: 14%-25%, I2 = 98%) and that of superinfection was 24% (95% CI: 19%-30%). Pooled prevalence of pathogen type stratified by co- or superinfection were: viral co-infections, 10% (95% CI: 6%-14%); viral superinfections, 4% (95% CI: 0%-10%); bacterial co-infections, 8% (95% CI: 5%-11%); bacterial superinfections, 20% (95% CI: 13%-28%); fungal co-infections, 4% (95% CI: 2%-7%); and fungal superinfections, 8% (95% CI: 4%-13%). Patients with a co-infection or superinfection had higher odds of dying than those who only had SARS-CoV-2 infection (odds ratio = 3.31, 95% CI: 1.82-5.99). Compared to those with co-infections, patients with superinfections had a higher prevalence of mechanical ventilation (45% [95% CI: 33%-58%] vs. 10% [95% CI: 5%-16%]), but patients with co-infections had a greater average length of hospital stay than those with superinfections (mean = 29.0 days, standard deviation [SD] = 6.7 vs. mean = 16 days, SD = 6.2, respectively).Our study showed that as many as 19% of patients with COVID-19 have co-infections and 24% have superinfections. The presence of either co-infection or superinfection was associated with poor outcomes, including increased mortality. Our findings support the need for diagnostic testing to identify and treat co-occurring respiratory infections among patients with SARS-CoV-2 infection.

Poly(α-l-lysine) (PLL) is a class of water-soluble, cationic biopolymer composed of α-l-lysine structural units. The previous decade witnessed tremendous progress in the synthesis and biomedical applications of PLL and its composites. PLL-based polymers and copolymers, till date, have been extensively explored in the contexts such as antibacterial agents, gene/drug/protein delivery systems, bio-sensing, bio-imaging, and tissue engineering. This review aims to summarize the recent advances in PLL-based nanomaterials in these biomedical fields over the last decade. The review first describes the synthesis of PLL and its derivatives, followed by the main text of their recent biomedical applications and translational studies. Finally, the challenges and perspectives of PLL-based nanomaterials in biomedical fields are addressed., Graphical abstract Image 1, Highlights • Focusing on biomedical applications of PLL-based nanomaterials. • Discussing antibacterial agents, delivery systems, bio-sensing, bio-imaging, and tissue engineering in detail. • Addressing perspectives of PLL-based nanomaterials in biomedical fields.

Efficient, environmentally and economically sustainable, and nontoxic antibacterial products are of global relevance in the fight against microorganism contamination. In this work, an easy and straightforward method for the synthesis of bis‐morpholino triazine quaternary ammonium salts (bis‐mTQAS) is reported, starting from 2,4,6‐trichloro‐1,3,5‐triazine or 2,4‐dichloro‐6‐methoxy‐1,3,5‐triazine and various N‐alkylmorpholines. Bis‐mTQAS were tested as antimicrobials against Gram‐negative and Gram‐positive bacterial strains. The best‐performing bis‐mTQAS were found to achieve total disinfection against Staphylococcus aureus ATCC 25923 and Escherichia coli ATCC 25922 at 50 and 400 μg/mL, respectively. Distinctively, bis‐mTQAS with the highest antimicrobial efficiency had lowest cytotoxicity., An easy and straightforward methodology for the synthesis of bis‐morpholino triazine quaternary ammonium salts (bis‐mTQAS) is reported, starting from 2,4,6‐trichloro‐1,3,5‐triazine or 2,4‐dichloro‐6‐methoxy‐1,3,5‐triazine and various N‐alkylmorpholines. These bis‐mTQAS show significant promise as antimicrobial agents against Gram‐negative and Gram‐positive bacterial strains.

Isatin and its derivatives are important heterocycles found in nature and present in numerous bioactive compounds which possess various biological activities. Moreover, it is an essential building block in organic synthesis. The discovery of novel compounds active against human pathogenic bacteria and fungi is an urgent need, and the isatin may represent the suitable scaffold in the design of biologically relevant antimicrobials. A small library of 18 isatin hybrids was synthetized and evaluated for their antimicrobial potential on three reference strains: S. aureus, E. coli, both important human pathogens infamous for causing community- and hospital-acquired severe systemic infections; and C. albicans, responsible for devastating invasive infections, mainly in immunocompromised individuals. The study highlighted two lead compounds, 6k and 6m, endowed with inhibitory activity against S. aureus at very low concentrations (39.12 and 24.83 µg/mL, respectively).

A total of 50 cases of bovine clinical mastitis in Tripoli were subjected to microbiological examination. Thirty-five bacterial isolates were obtained and further identified by using the biochemical tests.Staphylococcus spp.(36%) was the predominant causative organism, then E. coli (24%) andStreptococcus spp. (6%) Additionally, twelve cases were caused by nonbacterial agents. The bacteria isolates were tested for theirin-vitrosusceptibility to different antimicrobial agents that are used in commercial intramammary infusion products. Antibacterial susceptibility testing showed that the bacteria isolates were sensitive to ciprofloxacin (100%), enrofloxacin (96%), cefotaxime (90%), deoxicillin (88.8%), clorophenicol (66.5), ampicillin (62.5%), amoxicillin (50%), vancomycin (42%) and fusidic acid (33.3%). According to these results, the ciprofloxacin was proved to be the drug of choice.

The main problems directly linked with the use of PMMA bone cements in orthopedic surgery are the improper mechanical bond between cement and bone and the absence of antimicrobial properties. Recently, more research has been devoted to new bone cement with antimicrobial properties using mainly antibiotics or other innovative materials with antimicrobial properties. In this paper, we developed modified PMMA bone cement with antimicrobial properties proposing some experimental antimicrobial agents consisting of silver nanoparticles incorporated in ceramic glass and hydroxyapatite impregnated with peppermint oil. The impact of the addition of antimicrobial agents on the structure, mechanical properties, and biocompatibility of new PMMA bone cements was quantified. It has been shown that the addition of antimicrobial agents improves the flexural strength of the traditional PMMA bone cement, while the yield strength values show a decrease, most likely because this agent acts as a discontinuity inside the material rather than as a reinforcing agent. In the case of all samples, the addition of antimicrobial agents had no significant influence on the thermal stability. The new PMMA bone cement showed good biocompatibility and the possibility of osteoblast proliferation (MTT test) along with a low level of cytotoxicity (LDH test).

The increasing prevalence of antimicrobial-resistant (AMR) bacteria along with the limited development of antimicrobials warrant investigating novel antimicrobial modalities. Emerging inorganic engineered nanomaterials (ENMs), most notably silver nanoparticles (AgNPs), have demonstrated superior antimicrobial properties. However, AgNPs, particularly those of small size, could exert overt toxicity to mammalian cells. This study investigated whether combining AgNPs and conventional antimicrobials would produce a synergistic response and determined the optimal and safe minimum inhibitory concentration (MIC) range against several wild-type Gram-positive and -negative strains and three different clinical isolates of AMR Klebsiella pneumoniae. Furthermore, the cytotoxicity of the synergistic combinations was assessed in a human hepatocyte model. The results showed that the AgNPs (15–25 nm) were effective against Gram-negative bacteria (MIC of 16–128 µg/mL) but not Gram-positive strains (MIC of 256 µg/mL). Both wild-type and AMR K. pneumoniae had similar MIC values following exposure to AgNPs. Importantly, co-exposure to combinations of AgNPs and antimicrobial agents, including kanamycin, colistin, rifampicin, and vancomycin, displayed synergy against both wild-type and AMR K. pneumoniae isolates (except for vancomycin against AMR strain I). Notably, the tested combinations demonstrated no to minimal toxicity against hepatocytes. Altogether, this study indicates the potential of combining AgNPs with conventional antimicrobials to overcome AMR bacteria.

International audience; The lack of novel drugs in development and the combination of increased incidence of drugresistant strains of bacteria has created the need for the search for new antimicrobials as well as new original strategies to fight bacterial resistance. In this context, a series of polyamine quinoline derivatives were prepared and biologically evaluated, identifying compounds able to sensitize doxycycline activity towards the Gram-negative bacteria P. aeruginosa. Of note was the identification of antibiotic enhancing analogues whose cytotoxicity ranged from negligible to significant. The mechanism of action of two of the best compounds was studied against P. aeruginosa and S. aureus establishing a different behaviour towards integrity or depolarization of bacterial membranes depending on the structure of the considered polyamine quinoline derivatives.

Introducción. El envasado de alimentos ha jugado un papel importante y variado, siempre de acuerdo con los requisitos y exigencias del mercado. Actualmente, estas necesidades se centran en el objetivo de tener alimentos seguros e inocuos durante el mayor tiempo posible. Para ello, se ha ampliado el estudio y desarrollo de nuevas tecnologías para el envasado de alimentos, que proporcionan las condiciones y características necesarias para alcanzar el objetivo propuesto. Objetivo. Presentar los avances más recientes en el campo del envasado de alimentos (activo e inteligente), incluyendo las perspectivas del impacto económico alcanzado y su correspondiente proyección futura. Desarrollo. Este trabajo presenta diferentes técnicas y criterios que se consideran utilizados para proponer el concepto de envasado activo, que cuenta con las condiciones necesarias para el suministro o supresión de sustancias o componentes generados en el mismo y que contribuyen a la conservación y deterioro de los alimentos contenidos. Al mismo tiempo, se presenta la tecnología conocida como embalaje inteligente, dotada de los recursos necesarios para monitorizar, e interpretar el estado interno del envase, comunicando esta situación fuera del mismo. En ambos casos, se promueve el uso de agentes o compuestos de origen natural para minimizar sus implicaciones sobre la salud y la modificación de los alimentos implicados. Conclusiones. La generación de envases activos e inteligentes requiere una evaluación individual de cada alimento específico, frente a los componentes utilizados. Conocer las concentraciones, según la característica que se requiera controlar, y así, comprender las posibles interacciones que se pueden producir entre el contenido y el recipiente que lo contiene. Introducción. El envasado de alimentos ha jugado papeles importantes y variados, siempre de acuerdo con los requerimientos y demandas del mercado. Actualmente, estas necesidades se centran en el objetivo de tener alimentos seguros e inocuos durante el mayor tiempo posible. Para ello, se ha ampliado el estudio y desarrollo de nuevas tecnologías para el envasado de alimentos, que aportan las condiciones y características necesarias para conseguir el objetivo propuesto. Objetivo. Presentar los avances más recientes en el campo de los envases para alimentos (activos e inteligentes), incluyendo las perspectivas del impacto económico alcanzado y su correspondiente proyección futura. Desarrollo. Este trabajo presenta diferentes técnicas y criterios los considerados utilizados para proponer el concepto de envase activo, que cuenta con las condiciones necesarias para el suministro o supresión de sustancias o componentes generados en él y que contribuyan a la conservación y deterioro del alimento contenido. Paralelamente, se presenta la tecnología conocida como envase inteligente, dotada de los recursos necesarios para monitorizar e interpretar el estado interno del contenedor, comunicando esta situación fuera de él. En ambos casos, se promueve el uso de agentes o compuestos de origen natural para minimizar sus implicaciones en la salud y la modificación de los alimentos involucrados. Conclusiones. La generación de envases activos e inteligentes, requieren una evaluación individual de cada alimento específico, frente a los componentes utilizados. Para conocer las concentraciones, según la característica que se requiera controlar, y de este modo, comprender las posibles interacciones que pueden ocurrir entre el contenido y el recipiente que lo contiene.

Antimicrobial resistance is a serious threat to global health, causing increased mortality and morbidity especially among critically ill patients. This toll is expected to rise following the COVID-19 pandemic. Carbapenem-resistant Acinetobacter baumannii (CRAb) is among the Gram-negative pathogens leading antimicrobial resistance globally; it is listed as a critical priority pathogen by the WHO and is implicated in hospital-acquired infections and outbreaks, particularly in critically ill patients. Recent reports from Lebanon describe increasing rates of infection with CRAb, hence the need to develop concerted interventions to control its spread. We set to describe the impact of combining antimicrobial stewardship and infection control measures on resistance rates and colonization pressure of CRAb in the intensive care units of a tertiary care center in Lebanon before the COVID-19 pandemic. The antimicrobial stewardship program introduced a carbapenem-sparing initiative in April 2019. During the same period, infection control interventions involved focused screening, monitoring, and tracking of CRAb, as well as compliance with specific measures. From January 2018 to January 2020, we report a statistically significant decrease in carbapenem consumption and a decrease in resistance rates of isolated A. baumannii. The colonization pressure of CRAb also decreased significantly, reaching record low levels at the end of the intervention period. The results indicate that a multidisciplinary approach and combined interventions between the stewardship and infection control teams can lead to a sustained reduction in resistance rates and CRAb spread in ICUs.

[EN] Enterobacterales resistant to carbapenems or producing extended-spectrum β-lactamases (ESBL) and non-fermenters resistant to carbapenems present resistance to many of the antimicrobials commonly used in clinical practice, and have been recognized by the World Health Organization as a critical priority for the development of new antimicrobials. In this review, the main mechanisms of resistance of Enterobacterales, Pseudomonas aeruginosa, Acinetobacter baumannii and Stenotrophomonas maltophilia to β-lactams, quinolones, aminoglycosides and polymyxins will be addressed. Updated information will be presented on the importance in resistance of antimicrobial modification mechanisms (including class C or extended-spectrum β-lactamases, carbapenemases and aminoglycoside-modifying enzymes), permeability alterations due to porin or lipopolysaccharide expression disorders, production of active efflux pumps, target alterations or protection, and expression of two-component systems., [ES] Los Enterobacterales resistentes a carbapenémicos o productores de betalactamasas de espectro extendido (BLEE) y los no fermentadores resistentes a carbapenémicos presentan resistencia a muchos de los antimicrobianos comúnmente empleados en la práctica clínica, y han sido reconocidos por la Organización Mundial de la Salud como una prioridad crítica para el desarrollo de nuevos antimicrobianos. En esta revisión se abordarán los principales mecanismos de resistencia de los Enterobacterales, Pseudomonas aeruginosa, Acinetobacter baumannii y Stenotrophomonas maltophilia a betalactámicos, quinolonas, aminoglucósidos y polimixinas. Se presentará información actualizada sobre la importancia en la resistencia de mecanismos de modificación de antimicrobianos (incluyendo betalactamasas de clase C de espectro extendido, carbapenemasas y enzimas modificadoras de aminoglucósidos), alteraciones de la permeabilidad por trastornos en la expresión de porinas o del lipopolisacárido, producción de bombas de expulsión activa, alteraciones de la diana o protección de la misma y expresión de sistemas de doble componente.

It seems quite challenging in tissue engineering to synthesize a base material with a range of essential activities, including biocompatibility, nontoxicity, and antimicrobial activities. Various types of materials are synthesized to solve the problem. This study aimed to provide the latest relevant information for practitioners about antibacterial scaffolds in dental tissue engineering. The PubMed search engine was used to review the relevant studies with a combination of the following terms as search queries: tissue engineering, scaffolds, antimicrobial, dentistry, dental stem cells, and oral diseases. It is noteworthy to state that only the terms related to tissue engineering in dentistry were considered. The antimicrobial scaffolds support the local tissue regeneration and prevent adverse inflammatory reactions; however, not all scaffolds have such positive characteristics. To resolve this potential defect, different antimicrobial agents are used during the synthesis process. Innovative methods in guided tissue engineering are actively working towards new ways to control oral and periodontal diseases.

Antimicrobial resistance is a global crisis which requires urgent action to halt its spread. The rate of deaths due to antibiotic resistance from bacterial infection reached 25,000 annually. Resistance rates to Escherichia coli and Klebsiella pneumoniae has risen to reach 40% and 56% respectively, in addition to high resistance rates of Acinetobacter baumannii to fluroquinolones and other antibiotics that reached 56%. So it has become an urgent need to establish robust programs to control antibiotic resistance and optimize the use of antibiotics in hospitals. In Egypt particularly, the rate of antibiotic resistance becomes high due to wrong traditions of dispensing and administration antibiotics in hospitals and pharmacies, all that drove us to build a program controlling all these obstacles. Antimicrobial stewardship programs (ASPs) are strategic programs to prevent development of microbial resistance and monitor prescription patterns of clinicians inside hospitals. In addition to minimize the toxic effects, overuse of antibiotics and improve the patient health, and minimize the emergence of antibiotic resistance in shadow of the lack of development of novel antimicrobial agents. In this review, we aimed to discuss antimicrobial stewardship programs, their core elements, clinical importance, essential requirements and their implementation in Egypt. In conclusion, the development of national guidelines for antimicrobial stewardship programs would be a useful step to help clinicians in making evidence-based treatment choices regarding antibiotic therapy and implementation of better antibiotic during pandemics. We hope this review help the medical staff to perform stewardship programs to control the antibiotic resistance in Egypt healthcare settings.

The size of metal nanoparticles (NPs) is crucial in their biomedical applications. Although abundant studies on the size effects of metal NPs in the range of 2–100 nm have been conducted, the exploration of the ultrasmall metal nanoclusters (NCs) of ~1 nm in size with unique features is quite limited. We synthesize three different sized gold (Au) NCs of different Au atom numbers and two bigger sized Au NPs protected by the same ligand to study the size influence on antimicrobial efficacy. The ultrasmall Au NCs can easily traverse the cell wall pores to be internalized inside bacteria, inducing reactive oxygen species generation to oxidize bacterial membrane and disturb bacterial metabolism. This explains why the Au NCs are antimicrobial while the Au NPs are non-antimicrobial, suggesting the key role of size in antimicrobial ability. Moreover, in contrast to the widely known size-dependent antimicrobial properties, the Au NCs of different atom numbers demonstrate molecule-like instead of size-dependent antimicrobial behavior with comparable effectiveness, indicating the unique molecule-like feature of ultrasmall Au NCs. Overcoming the bacterial defenses at the wall with ultrasmall Au NCs changes what was previously believed to harmless to the bacteria instead to a highly potent agent against the bacteria., Graphical abstract Image 1, Highlights • Size of nanomaterials plays a key role in biomedical applications, especially in antimicrobial behaviors. • The ultrasmall gold nanoclusters (Au NCs) less than 2 nm can easily traverse the cell wall pores to be internalized inside bacteria to kill bacteria. • The gold nanoparticles (Au NPs) are too big to be effectively internalized inside bacteria, failing to kill bacteria. • Au NCs of different atom numbers (i.e. different size) demonstrate molecule-like instead of size-dependent antimicrobial behavior.

Background: Antibiotic resistance (ABR) is at the top of global health threats. This paper aims to assess Polish physicians’ readiness to impact ABR through prescribing routines. Methods: Surveying Polish physicians participating in specialization courses at the Center for Postgraduate Medical Education in Warsaw, Poland from October 2019 to March 2020. Results: Information was obtained from 504 physicians aged 25–59, mean 32.8 ± 5.9 years, mainly women (65%). Most doctors (78%) prescribed antibiotics at least once a week. Physicians indicated clinical practice guidelines as resources most often consulted in the management of infections (90%). However, clinical experience was also declared a powerful resource. In total, 54% of respondents recalled receiving information about the prudent use of antibiotics within 12 months, which partially translated into changing views (56%) and practice (42%). Physicians disagreed that national campaigns provide good promotion of prudent antibiotics use (75%) or that they are effective (61%). Only 40% of doctors were aware of the national campaign promoting responsible antibiotics use, 24% had heard about the European Antibiotic Awareness Day and 20% knew about the World Antimicrobial Awareness Week. Conclusions: Prescribers most often rely on clinical practice guidelines and their own experience as resources for antibiotics use. Doctors’ awareness of available resources and information campaigns concerning antibiotics and antibiotic resistance should be improved.

Periprosthetic joint infection (PJI) is a difficult complication requiring a comprehensive eradication protocol. Cure rates have essentially stalled in the last two decades, using methods of antimicrobial cement joint spacers and parenteral antimicrobial agents. Functional spacers with higher-dose antimicrobial-loaded cement and antimicrobial-loaded calcium sulphate beads have emphasized local antimicrobial delivery on the premise that high-dose local antimicrobial delivery will enhance eradication. However, with increasing antimicrobial pressures, microbiota have responded with adaptive mechanisms beyond traditional antimicrobial resistance genes. In this review we describe adaptive resistance mechanisms that are relevant to the treatment of PJI. Some mechanisms are well known, but others are new. The objective of this review is to inform clinicians of the known adaptive resistance mechanisms of microbes relevant to PJI. We also discuss the implications of these adaptive mechanisms in the future treatment of PJI. Cite this article: Bone Joint J 2022;104-B(5):575–580.

Different types of spices used daily have been documented to have antimicrobial and medicinal value as well. Most bacteria are sensitive to the extracts from plants such as, garlic, onion, thyme and turmeric etc. Spices such as these have been used as antimicrobial agents in their raw form for the treatment of wounds, injuries and joint pains etc. The present study was conducted to investigate the antibacterial activity of these natural spices. Different concentrations of extracts were prepared by using two solvents; water and ethanol, the test organisms used wereEscherichia coli and Staphylococcus aureus. All the spices used were effective against the test organisms, but the best activity was shown in garlic, while the least activity was shown in thyme, in general, the ethanolic extracts were more reactive than the aqueous extracts. Natural spices could be a potential source for antimicrobial agents. Validation of natural spices as alternative and complementary medicine can be achieved by several in vivo trials through which the safe use of such products can be assured. This study emphasizes the therapeutic potential of spices and the need to enhance its exploitation on this regard.

Background Tuberculosis (TB) is a communicable, preventable and curable disease caused by the bacterium Mycobacterium tuberculosis (MTB). Peru is amongst the 30 countries with the highest burden of multidrug-resistant tuberculosis (MDR-TB) worldwide. In the fight against drug-resistant tuberculosis, the UKMYC6 microdilution plate was developed and validated by the CRyPTIC project. The objective of the study was to evaluate the use of the broth microdilution (BMD) plate methodology for susceptibility testing of drug-resistant MTB strains in Peru. Methods MTB strains isolated between 2015 and 2018 in Peru were used. 496 nationally-representative strains determined as drug-resistant by the routine 7H10 Agar Proportion Method (APM) were included in the present study. The Minimum Inhibitory Concentration (MIC) of 13 antituberculosis drugs were determined for each strain using the UKMYC6 microdilution plates. Diagnostic agreement between APM and BMD plate methodology was determined for rifampicin, isoniazid, ethambutol, ethionamide, kanamycin and levofloxacin. Phenotypes were set using binary (or ternary) classification based on Epidemiological cut-off values (ECOFF/ECV) proposed by the CRyPTIC project. Whole Genome Sequencing (WGS) was performed on strains with discrepant results between both methods. Results MIC distributions were determined for 13 first- and second-line anti-TB drugs, including new (bedaquiline, delamanid) and repurposed (clofazimine, linezolid) agents. MIC results were available for 80% (397/496) of the strains at 14 days and the remainder at 21 days. The comparative analysis determined a good agreement (0.64 ≤ k ≤ 0.79) for the drugs rifampicin, ethambutol, ethionamide and kanamycin, and the best agreement (k > 0.8) for isoniazid and levofloxacin. Overall, 12% of MIC values were above the UKMYC6 plate dilution ranges, most notably for the drugs rifampicin and rifabutin. No strain presented MICs higher than the ECOFF/ECV values for the new or repurposed drugs. Discrepant analysis using genotypic susceptibility testing by WGS supported half of the results obtained by APM (52%, 93/179) and half of those obtained by BMD plate methodology (48%, 86/179). Conclusions The BMD methodology using the UKMYC6 plate allows the complete susceptibility characterization, through the determination of MICs, of drug-resistant MTB strains in Peru. This methodology shows good diagnostic performances for rifampicin, isoniazid, ethambutol, ethionamide, kanamycin and levofloxacin. It also allows for the characterization of MICs for other drugs used in previous years against tuberculosis, as well as for new and repurposed drugs recently introduced worldwide.