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1.
Pediatr Infect Dis J ; 41(4): e142-e145, 2022 04 01.
Article in English | MEDLINE | ID: covidwho-1752202

ABSTRACT

We reviewed all cases of Panton-Valentine leukocidin-producing Staphylococcus aureus (PVL-SA) bacteremia in Danish children between 2016 and 2021. We found 2 fatal cases with preceding viral prodrome due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Given the usual benign course of SARS-CoV-2 infection in children, awareness of possible superinfection with PVL-SA in a child with rapid deterioration is crucial to ensure adequate treatment, including antimicrobial drugs with antitoxin effect.


Subject(s)
Bacteremia , Bacterial Toxins/biosynthesis , COVID-19/complications , Exotoxins/biosynthesis , Leukocidins/biosynthesis , SARS-CoV-2 , Staphylococcal Infections/etiology , Staphylococcal Infections/mortality , Staphylococcus aureus/genetics , Adolescent , COVID-19/virology , Child , Child, Preschool , Coinfection , Comorbidity , Denmark/epidemiology , Female , Humans , Infant , Male , Methicillin-Resistant Staphylococcus aureus/genetics , Methicillin-Resistant Staphylococcus aureus/metabolism , Public Health Surveillance , Severity of Illness Index , Staphylococcal Infections/diagnosis , Staphylococcal Infections/therapy , Staphylococcus aureus/drug effects , Staphylococcus aureus/metabolism
2.
Mar Drugs ; 20(1)2022 Jan 11.
Article in English | MEDLINE | ID: covidwho-1667236

ABSTRACT

The underexplored biodiversity of seaweeds has recently drawn great attention from researchers to find the bioactive compounds that might contribute to the growth of the blue economy. In this study, we aimed to explore the effect of seasonal growth (from May to September) on the in vitro antioxidant (FRAP, DPPH, and ORAC) and antimicrobial effects (MIC and MBC) of Cystoseira compressa collected in the Central Adriatic Sea. Algal compounds were analyzed by UPLC-PDA-ESI-QTOF, and TPC and TTC were determined. Fatty acids, among which oleic acid, palmitoleic acid, and palmitic acid were the dominant compounds in samples. The highest TPC, TTC and FRAP were obtained for June extract, 83.4 ± 4.0 mg GAE/g, 8.8 ± 0.8 mg CE/g and 2.7 ± 0.1 mM TE, respectively. The highest ORAC value of 72.1 ± 1.2 µM TE was obtained for the August samples, and all samples showed extremely high free radical scavenging activity and DPPH inhibition (>80%). The MIC and MBC results showed the best antibacterial activity for the June, July and August samples, when sea temperature was the highest, against Listeria monocytogenes, Staphylococcus aureus, and Salmonella enteritidis. The results show C. compressa as a potential species for the industrial production of nutraceuticals or functional food ingredients.


Subject(s)
Anti-Bacterial Agents/pharmacology , Antioxidants/pharmacology , Plant Extracts/pharmacology , Seaweed , Animals , Anti-Bacterial Agents/chemistry , Antioxidants/chemistry , Aquatic Organisms , Biphenyl Compounds , Mediterranean Sea , Microbial Sensitivity Tests , Picrates , Plant Extracts/chemistry , Salmonella enteritidis/drug effects , Seasons , Staphylococcus aureus/drug effects
3.
Microbiol Spectr ; 10(1): e0052221, 2022 02 23.
Article in English | MEDLINE | ID: covidwho-1622001

ABSTRACT

Heme-containing peroxidases are widely distributed in the animal and plant kingdoms and play an important role in host defense by generating potent oxidants. Myeloperoxidase (MPO), the prototype of heme-containing peroxidases, exists in neutrophils and monocytes. MPO has a broad spectrum of microbial killing. The difficulty of producing MPO at a large scale hinders its study and utilization. This study aimed to overexpress recombinant human MPO and characterize its microbicidal activities in vitro and in vivo. A human HEK293 cell line stably expressing recombinant MPO (rMPO) was established as a component of this study. rMPO was overexpressed and purified for studies on its biochemical and enzymatic properties, as well as its microbicidal activities. In this study, rMPO was secreted into culture medium as a monomer. rMPO revealed enzymatic activity similar to that of native MPO. rMPO, like native MPO, was capable of killing a broad spectrum of microorganisms, including Gram-negative and -positive bacteria and fungi, at low nM levels. Interestingly, rMPO could kill antibiotic-resistant bacteria, making it very useful for treatment of nosocomial infections and mixed infections. The administration of rMPO significantly reduced the morbidity and mortality of murine lung infections induced by Pseudomonas aeruginosa or methicillin-resistant Staphylococcus aureus. In animal safety tests, the administration of 100 nM rMPO via tail vein did not result in any sign of toxic effects. Taken together, the data suggest that rMPO purified from a stably expressing human cell line is a new class of antimicrobial agents with the ability to kill a broad spectrum of pathogens, including bacteria and fungi with or without drug resistance. IMPORTANCE Over the past 2 decades, more than 20 new infectious diseases have emerged. Unfortunately, novel antimicrobial therapeutics are discovered at much lower rates. Infections caused by resistant microorganisms often fail to respond to conventional treatment, resulting in prolonged illness, greater risk of death, and high health care costs. Currently, this is best seen with the lack of a cure for coronavirus disease 2019 (COVID-19). To combat such untreatable microorganisms, there is an urgent need to discover new classes of antimicrobial agents. Myeloperoxidase (MPO) plays an important role in host defense. The difficulty of producing MPO on a large scale hinders its study and utilization. We have produced recombinant MPO at a large scale and have characterized its antimicrobial activities. Most importantly, recombinant MPO significantly reduced the morbidity and mortality of murine pneumonia induced by Pseudomonas aeruginosa or methicillin-resistant Staphylococcus aureus. Our data suggest that recombinant MPO from human cells is a new class of antimicrobials with a broad spectrum of activity.


Subject(s)
Anti-Infective Agents/pharmacology , Peroxidase/pharmacology , Acute Disease , Animals , Anti-Infective Agents/classification , Anti-Infective Agents/therapeutic use , Anti-Infective Agents/toxicity , Candida albicans/drug effects , Drug Resistance, Bacterial , Escherichia coli/drug effects , Female , HEK293 Cells , Humans , Hydrogen Peroxide/toxicity , Male , Methicillin-Resistant Staphylococcus aureus/drug effects , Mice , Mice, Inbred C57BL , Peroxidase/genetics , Peroxidase/therapeutic use , Peroxidase/toxicity , Pneumonia, Bacterial/drug therapy , Pseudomonas Infections/drug therapy , Pseudomonas aeruginosa/drug effects , Recombinant Proteins/genetics , Recombinant Proteins/pharmacology , Recombinant Proteins/therapeutic use , Recombinant Proteins/toxicity , Staphylococcal Infections/drug therapy , Staphylococcus aureus/drug effects
4.
Science ; 372(6547): 1169-1175, 2021 06 11.
Article in English | MEDLINE | ID: covidwho-1583231

ABSTRACT

Emergent resistance to all clinical antibiotics calls for the next generation of therapeutics. Here we report an effective antimicrobial strategy targeting the bacterial hydrogen sulfide (H2S)-mediated defense system. We identified cystathionine γ-lyase (CSE) as the primary generator of H2S in two major human pathogens, Staphylococcus aureus and Pseudomonas aeruginosa, and discovered small molecules that inhibit bacterial CSE. These inhibitors potentiate bactericidal antibiotics against both pathogens in vitro and in mouse models of infection. CSE inhibitors also suppress bacterial tolerance, disrupting biofilm formation and substantially reducing the number of persister bacteria that survive antibiotic treatment. Our results establish bacterial H2S as a multifunctional defense factor and CSE as a drug target for versatile antibiotic enhancers.


Subject(s)
Anti-Bacterial Agents/pharmacology , Cystathionine gamma-Lyase/antagonists & inhibitors , Enzyme Inhibitors/pharmacology , Hydrogen Sulfide/metabolism , Pseudomonas aeruginosa/drug effects , Staphylococcus aureus/drug effects , Animals , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/metabolism , Biofilms , Crystallography, X-Ray , Cystathionine gamma-Lyase/chemistry , Cystathionine gamma-Lyase/genetics , Cystathionine gamma-Lyase/metabolism , Drug Discovery , Drug Resistance, Bacterial , Drug Synergism , Drug Tolerance , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/metabolism , Mice , Microbial Sensitivity Tests , Models, Molecular , Molecular Docking Simulation , Molecular Structure , Pseudomonas Infections/drug therapy , Pseudomonas Infections/microbiology , Pseudomonas aeruginosa/enzymology , Pseudomonas aeruginosa/genetics , Pseudomonas aeruginosa/growth & development , Small Molecule Libraries/chemistry , Small Molecule Libraries/metabolism , Small Molecule Libraries/pharmacology , Staphylococcal Infections/drug therapy , Staphylococcal Infections/microbiology , Staphylococcus aureus/enzymology , Staphylococcus aureus/genetics , Staphylococcus aureus/growth & development
5.
Int J Mol Sci ; 22(23)2021 Nov 24.
Article in English | MEDLINE | ID: covidwho-1542581

ABSTRACT

The Coronavirus Disease (COVID-19) pandemic is demanding the rapid action of the authorities and scientific community in order to find new antimicrobial solutions that could inactivate the pathogen SARS-CoV-2 that causes this disease. Gram-positive bacteria contribute to severe pneumonia associated with COVID-19, and their resistance to antibiotics is exponentially increasing. In this regard, non-woven fabrics are currently used for the fabrication of infection prevention clothing such as face masks, caps, scrubs, shirts, trousers, disposable gowns, overalls, hoods, aprons and shoe covers as protective tools against viral and bacterial infections. However, these non-woven fabrics are made of materials that do not exhibit intrinsic antimicrobial activity. Thus, we have here developed non-woven fabrics with antimicrobial coatings of cranberry extracts capable of inactivating enveloped viruses such as SARS-CoV-2 and the bacteriophage phi 6 (about 99% of viral inactivation in 1 min of viral contact), and two multidrug-resistant bacteria: the methicillin-resistant Staphylococcus aureus and the methicillin-resistant Staphylococcus epidermidis. The morphology, thermal and mechanical properties of the produced filters were characterized by optical and electron microscopy, differential scanning calorimetry, thermogravimetry and dynamic mechanical thermal analysis. The non-toxicity of these advanced technologies was ensured using a Caenorhabditis elegans in vivo model. These results open up a new prevention path using natural and biodegradable compounds for the fabrication of infection prevention clothing in the current COVID-19 pandemic and microbial resistant era.


Subject(s)
Drug Resistance, Multiple, Bacterial/drug effects , Plant Extracts/pharmacology , SARS-CoV-2/drug effects , Textiles , Vaccinium macrocarpon/chemistry , Animals , Anti-Bacterial Agents , Anti-Infective Agents , Bacteriophage phi 6/drug effects , COVID-19/prevention & control , Caenorhabditis elegans/drug effects , Humans , Methicillin-Resistant Staphylococcus aureus , Staphylococcus aureus/drug effects , Staphylococcus epidermidis/drug effects
6.
Sci Rep ; 11(1): 22543, 2021 11 19.
Article in English | MEDLINE | ID: covidwho-1526103

ABSTRACT

Microbial contamination is one of the major dreadful problems that raises hospitalization, morbidity and mortality rates globally, which subsequently obstructs socio-economic progress. The continuous misuse and overutilization of antibiotics participate mainly in the emergence of microbial resistance. To circumvent such a multidrug-resistance phenomenon, well-defined nanocomposite structures have recently been employed. In the current study, a facile, novel and cost-effective approach was applied to synthesize Ag@Ag2O core-shell nanocomposites (NCs) via chemical method. Several techniques were used to determine the structural, morphological, and optical characteristics of the as-prepared NCs. XRD, Raman, FTIR, XPS and SAED analysis revealed a crystalline hybrid structure of Ag core and Ag2O shell. Besides, SEM and HRTEM micrographs depicted spherical nanoparticles with size range of 19-60 nm. Additionally, zeta potential and fluorescence spectra illustrated aggregated nature of Ag@Ag2O NCs by - 5.34 mV with fluorescence emission peak at 498 nm. Ag@Ag2O NCs exhibited higher antimicrobial, antibiofilm, and algicidal activity in dose-dependent behavior. Interestingly, a remarkable mycocidal potency by 50 µg of Ag@Ag2O NCs against Candida albican; implying promising activity against COVID-19 white fungal post-infections. Through assessing cytotoxicity, Ag@Ag2O NCs exhibited higher safety against Vero cells than bulk silver nitrate by more than 100-fold.


Subject(s)
Anti-Infective Agents/chemistry , Anti-Infective Agents/pharmacology , Biofilms/drug effects , Nanocomposites/chemistry , Oxides/chemistry , Silver Compounds/chemistry , Animals , Anti-Infective Agents/chemical synthesis , Candida albicans/drug effects , Cell Survival/drug effects , Chlorella vulgaris/drug effects , Chlorocebus aethiops , Disinfectants/chemical synthesis , Disinfectants/chemistry , Disinfectants/pharmacology , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Metal Nanoparticles/chemistry , Oxides/chemical synthesis , Pseudomonas aeruginosa/drug effects , Silver Compounds/chemical synthesis , Silver Nitrate/pharmacology , Staphylococcus aureus/drug effects , Vero Cells
7.
Microbiol Spectr ; 9(3): e0028321, 2021 12 22.
Article in English | MEDLINE | ID: covidwho-1501550

ABSTRACT

The Infectious Disease Surveillance of Pediatrics (ISPED) program was established in 2015 to monitor and analyze the trends of bacterial epidemiology and antimicrobial resistance (AMR) in children. Clinical bacterial isolates were collected from 11 tertiary care children's hospitals in China in 2016 to 2020. Antimicrobial susceptibility testing was carried out using the Kirby-Bauer method or automated systems, with interpretation according to the Clinical and Laboratory Standards Institute 2019 breakpoints. A total of 288,377 isolates were collected, and the top 10 predominant bacteria were Escherichia coli, Streptococcus pneumoniae, Staphylococcus aureus, Haemophilus influenzae, Klebsiella pneumoniae, Moraxella catarrhalis, Streptococcus pyogenes, Staphylococcus epidermidis, Pseudomonas aeruginosa, and Acinetobacter baumannii. In 2020, the coronavirus disease 2019 (COVID-19) pandemic year, we observed a significant reduction in the proportion of respiratory tract samples (from 56.9% to 44.0%). A comparable reduction was also seen in the primary bacteria mainly isolated from respiratory tract samples, including S. pneumoniae, H. influenzae, and S. pyogenes. Multidrug-resistant organisms (MDROs) in children were commonly observed and presented higher rates of drug resistance than sensitive strains. The proportions of carbapenem-resistant K. pneumoniae (CRKP), carbapenem-resistant A. baumannii (CRAB), carbapenem-resistant P. aeruginosa (CRPA), and methicillin-resistant S. aureus (MRSA) strains were 19.7%, 46.4%%, 12.8%, and 35.0%, respectively. The proportions of CRKP, CRAB, and CRPA strains all showed decreasing trends between 2015 and 2020. Carbapenem-resistant Enterobacteriaceae (CRE) and CRPA gradually decreased with age, while CRAB showed the opposite trend with age. Both CRE and CRPA pose potential threats to neonates. MDROs show very high levels of AMR and have become an urgent threat to children, suggesting that effective monitoring of AMR and antimicrobial stewardship among children in China are required. IMPORTANCE AMR, especially that involving multidrug-resistant organisms (MDROs), is recognized as a global threat to human health; AMR renders infections increasingly difficult to treat, constituting an enormous economic burden and producing tremendous negative impacts on patient morbidity and mortality rates. There are many surveillance programs in the world to address AMR profiles and MDRO prevalence in humans. However, published studies evaluating the overall AMR rates or MDRO distributions in children are very limited or are of mixed quality. In this study, we showed the bacterial epidemiology and resistance profiles of primary pathogens in Chinese children from 2016 to 2020 for the first time, analyzed MDRO distributions with time and with age, and described MDROs' potential threats to children, especially low-immunity neonates. Our study will be very useful to guide antiinfection therapy in Chinese children, as well as worldwide pediatric patients.


Subject(s)
Bacteria/classification , Communicable Diseases/epidemiology , Communicable Diseases/microbiology , Drug Resistance, Bacterial , Acinetobacter baumannii/drug effects , Anti-Bacterial Agents/pharmacology , Bacteria/drug effects , Bacteria/isolation & purification , COVID-19/epidemiology , Child , China/epidemiology , Drug Resistance, Bacterial/drug effects , Escherichia coli/drug effects , Humans , Klebsiella pneumoniae/drug effects , Methicillin-Resistant Staphylococcus aureus/drug effects , Microbial Sensitivity Tests , Moraxella catarrhalis , Pseudomonas aeruginosa/drug effects , SARS-CoV-2 , Staphylococcus aureus/drug effects , Staphylococcus epidermidis , Streptococcus pneumoniae , Streptococcus pyogenes
8.
Molecules ; 26(19)2021 Oct 06.
Article in English | MEDLINE | ID: covidwho-1463769

ABSTRACT

Pristine high-density bulk disks of MgB2 with added hexagonal BN (10 wt.%) were prepared using spark plasma sintering. The BN-added samples are machinable by chipping them into desired geometries. Complex shapes of different sizes can also be obtained by the 3D printing of polylactic acid filaments embedded with MgB2 powder particles (10 wt.%). Our present work aims to assess antimicrobial activity quantified as viable cells (CFU/mL) vs. time of sintered and 3D-printed materials. In vitro antimicrobial tests were performed against the bacterial strains Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Staphylococcus aureus ATCC 25923, Enterococcus faecium DSM 13590, and Enterococcus faecalis ATCC 29212; and the yeast strain Candida parapsilosis ATCC 22019. The antimicrobial effects were found to depend on the tested samples and microbes, with E. faecium being the most resistant and E. coli the most susceptible.


Subject(s)
Anti-Infective Agents/pharmacology , Bacteria/drug effects , Boron Compounds/pharmacology , Fungi/drug effects , Magnesium Compounds/pharmacology , Candida parapsilosis/drug effects , Enterococcus faecalis/drug effects , Enterococcus faecium/drug effects , Escherichia coli/drug effects , Microbial Sensitivity Tests , Polyesters/pharmacology , Printing, Three-Dimensional , Pseudomonas aeruginosa/drug effects , Staphylococcus aureus/drug effects
9.
Molecules ; 26(19)2021 Sep 23.
Article in English | MEDLINE | ID: covidwho-1463764

ABSTRACT

Due to their large possibility of the structure modification, alkylammonium gemini surfactants are a rapidly growing class of compounds. They exhibit significant surface, aggregation and antimicrobial properties. Due to the fact that, in order to achieve the desired utility effect, the minimal concentration of compounds are used, they are in line with the principle of greenolution (green evolution) in chemistry. In this study, we present innovative synthesis of the homologous series of gemini surfactants modified at the spacer by the ether group, i.e., 3-oxa-1,5-pentane-bis(N-alkyl-N,N-dimethylammonium bromides). The critical micelle concentrations were determined. The minimal inhibitory concentrations of the synthesized compounds were determined against bacteria Escherichia coli ATCC 10536 and Staphylococcus aureus ATCC 6538; yeast Candida albicans ATCC 10231; and molds Aspergillus niger ATCC 16401 and Penicillium chrysogenum ATCC 60739. We also investigated the relationship between antimicrobial activity and alkyl chain length or the nature of the spacer. The obtained results indicate that the synthesized compounds are effective microbicides with a broad spectrum of biocidal activity.


Subject(s)
Anti-Infective Agents/pharmacology , Quaternary Ammonium Compounds/pharmacology , Surface-Active Agents/pharmacology , Anti-Infective Agents/chemistry , Aspergillus niger/drug effects , Candida albicans/drug effects , Escherichia coli/drug effects , Green Chemistry Technology , Micelles , Microbial Sensitivity Tests , Molecular Structure , Penicillium chrysogenum/drug effects , Quaternary Ammonium Compounds/chemistry , Staphylococcus aureus/drug effects , Surface-Active Agents/chemistry
10.
J Am Chem Soc ; 143(40): 16777-16785, 2021 10 13.
Article in English | MEDLINE | ID: covidwho-1442692

ABSTRACT

The most recent global health crisis caused by the SARS-CoV-2 outbreak and the alarming use of chemical warfare agents highlight the necessity to produce efficient protective clothing and masks against biohazard and chemical threats. However, the development of a multifunctional protective textile is still behind to supply adequate protection for the public. To tackle this challenge, we designed multifunctional and regenerable N-chlorine based biocidal and detoxifying textiles using a robust zirconium metal-organic framework (MOF), UiO-66-NH2, as a chlorine carrier which can be easily coated on textile fibers. A chlorine bleaching converted the amine groups located on the MOF linker to active N-chlorine structures. The fibrous composite exhibited rapid biocidal activity against both Gram-negative bacteria (E. coli) and Gram-positive bacteria (S. aureus) with up to a 7 log reduction within 5 min for each strain as well as a 5 log reduction of SARS-CoV-2 within 15 min. Moreover, the active chlorine loaded MOF/fiber composite selectively and rapidly degraded sulfur mustard and its chemical simulant 2-chloroethyl ethyl sulfide (CEES) with half-lives less than 3 minutes. The versatile MOF-based fibrous composite designed here has the potential to serve as protective cloth against both biological and chemical threats.


Subject(s)
Anti-Bacterial Agents/pharmacology , Antiviral Agents/pharmacology , Chemical Warfare Agents/chemistry , Chlorine/pharmacology , Metal-Organic Frameworks/pharmacology , Protective Clothing , Animals , Anti-Bacterial Agents/chemical synthesis , Antiviral Agents/chemical synthesis , Cell Line , Chlorine/chemistry , Escherichia coli/drug effects , Halogenation , Humans , Metal-Organic Frameworks/chemical synthesis , Microbial Sensitivity Tests , Mustard Gas/analogs & derivatives , Mustard Gas/chemistry , Oxidation-Reduction , SARS-CoV-2/drug effects , Staphylococcus aureus/drug effects , Textiles , Zirconium/chemistry
11.
Sci Rep ; 11(1): 18444, 2021 09 16.
Article in English | MEDLINE | ID: covidwho-1415956

ABSTRACT

Over the past year, the world's attention has focused on combating COVID-19 disease, but the other threat waiting at the door-antimicrobial resistance should not be forgotten. Although making the diagnosis rapidly and accurately is crucial in preventing antibiotic resistance development, bacterial identification techniques include some challenging processes. To address this challenge, we proposed a deep neural network (DNN) that can discriminate antibiotic-resistant bacteria using surface-enhanced Raman spectroscopy (SERS). Stacked autoencoder (SAE)-based DNN was used for the rapid identification of methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-sensitive S. aureus (MSSA) bacteria using a label-free SERS technique. The performance of the DNN was compared with traditional classifiers. Since the SERS technique provides high signal-to-noise ratio (SNR) data, some subtle differences were found between MRSA and MSSA in relative band intensities. SAE-based DNN can learn features from raw data and classify them with an accuracy of 97.66%. Moreover, the model discriminates bacteria with an area under curve (AUC) of 0.99. Compared to traditional classifiers, SAE-based DNN was found superior in accuracy and AUC values. The obtained results are also supported by statistical analysis. These results demonstrate that deep learning has great potential to characterize and detect antibiotic-resistant bacteria by using SERS spectral data.


Subject(s)
Methicillin Resistance , Staphylococcus aureus/classification , Staphylococcus aureus/growth & development , Deep Learning , Discriminant Analysis , Humans , Metal Nanoparticles/chemistry , Microbial Sensitivity Tests , Neural Networks, Computer , Signal-To-Noise Ratio , Silver/chemistry , Spectrum Analysis, Raman , Staphylococcus aureus/drug effects , Support Vector Machine
12.
Int J Mol Sci ; 22(15)2021 Jul 27.
Article in English | MEDLINE | ID: covidwho-1332900

ABSTRACT

A novel series of N-substituted cis- and trans-3-aryl-4-(diethoxyphosphoryl)azetidin-2-ones were synthesized by the Kinugasa reaction of N-methyl- or N-benzyl-(diethyoxyphosphoryl)nitrone and selected aryl alkynes. Stereochemistry of diastereoisomeric adducts was established based on vicinal H3-H4 coupling constants in azetidin-2-one ring. All the obtained azetidin-2-ones were evaluated for the antiviral activity against a broad range of DNA and RNA viruses. Azetidin-2-one trans-11f showed moderate inhibitory activity against human coronavirus (229E) with EC50 = 45 µM. The other isomer cis-11f was active against influenza A virus H1N1 subtype (EC50 = 12 µM by visual CPE score; EC50 = 8.3 µM by TMS score; MCC > 100 µM, CC50 = 39.9 µM). Several azetidin-2-ones 10 and 11 were tested for their cytostatic activity toward nine cancerous cell lines and several of them appeared slightly active for Capan-1, Hap1 and HCT-116 cells values of IC50 in the range 14.5-97.9 µM. Compound trans-11f was identified as adjuvant of oxacillin with significant ability to enhance the efficacy of this antibiotic toward the highly resistant S. aureus strain HEMSA 5. Docking and molecular dynamics simulations showed that enantiomer (3R,4S)-11f can be responsible for the promising activity due to the potency in displacing oxacillin at ß-lactamase, thus protecting the antibiotic from undesirable biotransformation.


Subject(s)
Adjuvants, Pharmaceutic/chemistry , Adjuvants, Pharmaceutic/pharmacology , Antiviral Agents/chemistry , Antiviral Agents/pharmacology , Azetidines/pharmacology , Infections/drug therapy , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Azetidines/chemistry , Bacterial Proteins/chemistry , Cell Line, Tumor , Cell Proliferation/drug effects , Coronavirus 229E, Human/drug effects , Cytostatic Agents/chemistry , Cytostatic Agents/pharmacology , Humans , Influenza A Virus, H1N1 Subtype/drug effects , Molecular Dynamics Simulation , Oxacillin/chemistry , Penicillin-Binding Proteins/chemistry , Staphylococcus aureus/drug effects , Stereoisomerism , beta-Lactamases/chemistry
13.
Int J Mol Sci ; 22(13)2021 Jun 28.
Article in English | MEDLINE | ID: covidwho-1304665

ABSTRACT

The paper presents a synthesis of poly(l-lactide) with bacteriostatic properties. This polymer was obtained by ring-opening polymerization of the lactide initiated by selected low-toxic zinc complexes, Zn[(acac)(L)H2O], where L represents N-(pyridin-4-ylmethylene) tryptophan or N-(2-pyridin-4-ylethylidene) phenylalanine. These complexes were obtained by reaction of Zn[(acac)2 H2O] and Schiff bases, the products of the condensation of amino acids and 4-pyridinecarboxaldehyde. The composition, structure, and geometry of the synthesized complexes were determined by NMR and FTIR spectroscopy, elemental analysis, and molecular modeling. Both complexes showed the geometry of a distorted trigonal bipyramid. The antibacterial and antifungal activities of both complexes were found to be much stronger than those of the primary Schiff bases. The present study showed a higher efficiency of polymerization when initiated by the obtained zinc complexes than when initiated by the zinc(II) acetylacetonate complex. The synthesized polylactide showed antibacterial properties, especially the product obtained by polymerization initiated by a zinc(II) complex with a ligand based on l-phenylalanine. The polylactide showed a particularly strong antimicrobial effect against Pseudomonas aeruginosa, Staphylococcus aureus, and Aspergillus brasiliensis. At the same time, this polymer does not exhibit fibroblast cytotoxicity.


Subject(s)
Polyesters/chemistry , Polymers/chemistry , Zinc/chemistry , Anti-Infective Agents/chemistry , Anti-Infective Agents/pharmacology , Aspergillus/drug effects , Chelating Agents/chemistry , Pseudomonas aeruginosa/drug effects , Staphylococcus aureus/drug effects
14.
Molecules ; 26(12)2021 Jun 14.
Article in English | MEDLINE | ID: covidwho-1282538

ABSTRACT

Staphylococcus aureus (Gram-positive) and Pseudomonas aeruginosa (Gram-negative) bacteria represent major infectious threats in the hospital environment due to their wide distribution, opportunistic behavior, and increasing antibiotic resistance. This study reports on the deposition of polyvinylpyrrolidone/antibiotic/isoflavonoid thin films by the matrix-assisted pulsed laser evaporation (MAPLE) method as anti-adhesion barrier coatings, on biomedical surfaces for improved resistance to microbial colonization. The thin films were characterized by Fourier transform infrared spectroscopy, infrared microscopy, and scanning electron microscopy. In vitro biological assay tests were performed to evaluate the influence of the thin films on the development of biofilms formed by Gram-positive and Gram-negative bacterial strains. In vitro biocompatibility tests were assessed on human endothelial cells examined for up to five days of incubation, via qualitative and quantitative methods. The results of this study revealed that the laser-fabricated coatings are biocompatible and resistant to microbial colonization and biofilm formation, making them successful candidates for biomedical devices and contact surfaces that would otherwise be amenable to contact transmission.


Subject(s)
Anti-Bacterial Agents/pharmacology , Biofilms/drug effects , Coated Materials, Biocompatible/pharmacology , Drug Resistance, Microbial/drug effects , Flavonoids/pharmacology , Pseudomonas aeruginosa/drug effects , Staphylococcus aureus/drug effects , Anti-Bacterial Agents/chemistry , Biofilms/growth & development , Coated Materials, Biocompatible/chemistry , Flavonoids/chemistry , Lasers/standards , Microbial Sensitivity Tests/methods , Pseudomonas aeruginosa/growth & development , Staphylococcus aureus/growth & development , Surface Properties
15.
ACS Appl Mater Interfaces ; 13(11): 12912-12927, 2021 Mar 24.
Article in English | MEDLINE | ID: covidwho-1185365

ABSTRACT

The current pandemic caused by SARS-CoV-2 has seen a widespread use of personal protective equipment, especially face masks. This has created the need to develop better and reusable protective masks with built-in antimicrobial, self-cleaning, and aerosol filtration properties to prevent the transmission of air-borne pathogens such as the coronaviruses. Herein, molybdenum disulfide (MoS2) nanosheets are used to prepare modified polycotton fabrics having excellent antibacterial activity and photothermal properties. Upon sunlight irradiation, the nanosheet-modified fabrics rapidly increased the surface temperature to ∼77 °C, making them ideal for sunlight-mediated self-disinfection. Complete self-disinfection of the nanosheet-modified fabric was achieved within 3 min of irradiation, making the fabrics favorably reusable upon self-disinfection. The nanosheet-modified fabrics maintained the antibacterial efficiency even after 60 washing cycles. Furthermore, the particle filtration efficiency of three-layered surgical masks was found to be significantly improved through incorporation of the MoS2-modified fabric as an additional layer of protective clothing, without compromising the breathability of the masks. The repurposed surgical masks could filter out around 97% of 200 nm particles and 96% of 100 nm particles, thus making them potentially useful for preventing the spread of coronaviruses (120 nm) by trapping them along with antibacterial protection against other airborne pathogens.


Subject(s)
Anti-Infective Agents/chemistry , Disulfides/chemistry , Molybdenum/chemistry , Nanostructures/chemistry , Personal Protective Equipment , Recycling , Anti-Infective Agents/pharmacology , COVID-19/prevention & control , COVID-19/virology , Escherichia coli/drug effects , Escherichia coli/metabolism , Glutathione/chemistry , Humans , Nanostructures/toxicity , Oxidation-Reduction , Particle Size , Reactive Oxygen Species/metabolism , SARS-CoV-2/isolation & purification , Staphylococcus aureus/drug effects , Staphylococcus aureus/metabolism , Sunlight , Temperature
16.
Bioorg Med Chem Lett ; 36: 127808, 2021 03 15.
Article in English | MEDLINE | ID: covidwho-1034180

ABSTRACT

Commercial disinfectants are routinely used to decontaminate surfaces where microbes are expected and unwelcome. Several disinfectants contain quaternary ammonium salts, or "quats", all being derived from ammonium. Quaternary alkyl dimethyl benzyl ammonium chloride or bromide disinfectants are widely available. These compounds are effective in reducing or eliminating bacteria on contaminated nonporous surfaces. A unique benzyl derived boronium salt with strong detergent action has been developed. It demonstrated 4-8X greater antibacterial activity against 3 different bacteria when compared to an equal concentration of a commercial quant disinfectant solution containing alkyl dimethyl benzyl ammonium chloride and alkyl dimethyl ethylbenzyl ammonium chloride. Antibacterial effectiveness of each agent was determined by the minimum inhibitory concentration (MIC) method.


Subject(s)
Anti-Bacterial Agents/pharmacology , Bromides/pharmacology , Disinfectants/pharmacology , Quaternary Ammonium Compounds/pharmacology , Anti-Bacterial Agents/chemical synthesis , Anti-Bacterial Agents/chemistry , Bromides/chemical synthesis , Bromides/chemistry , Disinfectants/chemical synthesis , Disinfectants/chemistry , Dose-Response Relationship, Drug , Escherichia coli/drug effects , Microbial Sensitivity Tests , Molecular Structure , Pseudomonas aeruginosa/drug effects , Quaternary Ammonium Compounds/chemical synthesis , Quaternary Ammonium Compounds/chemistry , Staphylococcus aureus/drug effects , Structure-Activity Relationship
17.
Rev Esp Quimioter ; 34(2): 81-92, 2021 Apr.
Article in Spanish | MEDLINE | ID: covidwho-1145772

ABSTRACT

From a microbiological point of view, both empirical and targeted antimicrobial treatment in respiratory infection is based on the sensitivity profile of isolated microorganisms and the possible resistance mechanisms that they may present. The latter may vary in different geographic areas according to prescription profiles and vaccination programs. Beta-lactam antibiotics, fluoroquinolones, and macrolides are the most commonly used antimicrobials during the exacerbations of chronic obstructive pulmonary disease and community-acquired pneumonia. In their prescription, different aspects such as intrinsic activity, bactericidal effect or their ability to prevent the development of resistance must be taken into account. The latter is related to the PK/PD parameters, the mutant prevention concentration and the so-called selection window. More recently, the potential ecological impact has grown in importance, not only on the intestinal microbiota, but also on the respiratory one. Maintaining the state of eubiosis requires the use of antimicrobials with a low profile of action on anaerobic bacteria. With their use, the resilience of the bacterial populations belonging to the microbiota, the state of resistance of colonization and the collateral damage related to the emergence of resistance to the antimicrobials in pathogens causing the infections and in the bacterial populations integrating the microbiota.


Subject(s)
Anti-Bacterial Agents/pharmacology , COVID-19/epidemiology , Drug Resistance, Bacterial , Pulmonary Disease, Chronic Obstructive/drug therapy , Respiratory Tract Infections/drug therapy , Administration, Oral , Anti-Bacterial Agents/administration & dosage , Chlamydophila pneumoniae/drug effects , Community-Acquired Infections/drug therapy , Community-Acquired Infections/microbiology , Disease Progression , Gastrointestinal Microbiome/drug effects , Haemophilus influenzae/drug effects , Humans , Microbial Sensitivity Tests , Moraxella catarrhalis/drug effects , Mycoplasma pneumoniae/drug effects , Pseudomonas aeruginosa/drug effects , Pulmonary Disease, Chronic Obstructive/microbiology , Respiratory Tract Infections/microbiology , Staphylococcus aureus/drug effects , Streptococcus pneumoniae/drug effects
18.
Assay Drug Dev Technol ; 19(3): 156-175, 2021 04.
Article in English | MEDLINE | ID: covidwho-1137927

ABSTRACT

Corona virus disease-2019 (COVID-19) emerged in Wuhan, China in December 2019 and was declared as a pandemic by the World Health Organization in March 2020. Although there is no complete treatment protocol for COVID-19, studies on this topic are ongoing, and it is known that broad-spectrum antibiotics such as cephalosporins are used for coinfections and symptoms in COVID-19 patients. Studies have shown that Staphylococcus aureus and Escherichia coli bacteria can cause symptoms such as diarrhea and coinfections accompanying COVID-19. Therefore, in this study, colon-targeted cefaclor monohydrate (CEF)-loaded poly(lactic-co-glycolic acid) (PLGA)-Eudragit S100 nanoparticles (NPs) were prepared using a nanoprecipitation technique. The particle sizes of the CEF-loaded NPs were between 171.4 and 198.8 nm. The encapsulation efficiency was in the range of 58.4%-81.2%. With dissolution studies, it has been concluded that formulations prepared with Eudragit S100 (E-coded) and Eudragit S100+PLGA (EP-coded) are pH-sensitive formulations and they are targetable to the colon, whereas the formulation prepared only with PLGA (P-coded) can release a higher CEF rate in the colon owing to the slow release properties of PLGA. The release kinetics were fitted to the Korsmeyer-Peppas and Weibull models. The antibacterial activity of E-, EP-, and P-coded formulations was 16-fold, 16-fold, and 2-fold higher than CEF, respectively, for S. aureus and E. coli according to the microdilution results. As a result of the time killing experiment, all formulations prepared were found to be more effective than the antibiotic itself for long periods. Consequently, all formulations prepared in this study hope to guide researchers/clinicians in treating both gram-positive and gram-negative bacteria-induced infections, as well as COVID-19 associated coinfections and symptoms.


Subject(s)
Anti-Bacterial Agents/administration & dosage , Anti-Bacterial Agents/therapeutic use , Bacterial Infections/complications , Bacterial Infections/drug therapy , COVID-19/complications , Cefaclor/administration & dosage , Cefaclor/therapeutic use , Intestinal Diseases/complications , Intestinal Diseases/drug therapy , Anti-Bacterial Agents/pharmacology , Cefaclor/pharmacology , Coinfection , Drug Compounding , Escherichia coli/drug effects , Excipients , Kinetics , Microbial Sensitivity Tests , Nanoparticles , Particle Size , Polylactic Acid-Polyglycolic Acid Copolymer , Polymethacrylic Acids , Staphylococcus aureus/drug effects
19.
ACS Appl Mater Interfaces ; 13(11): 12912-12927, 2021 Mar 24.
Article in English | MEDLINE | ID: covidwho-1132024

ABSTRACT

The current pandemic caused by SARS-CoV-2 has seen a widespread use of personal protective equipment, especially face masks. This has created the need to develop better and reusable protective masks with built-in antimicrobial, self-cleaning, and aerosol filtration properties to prevent the transmission of air-borne pathogens such as the coronaviruses. Herein, molybdenum disulfide (MoS2) nanosheets are used to prepare modified polycotton fabrics having excellent antibacterial activity and photothermal properties. Upon sunlight irradiation, the nanosheet-modified fabrics rapidly increased the surface temperature to ∼77 °C, making them ideal for sunlight-mediated self-disinfection. Complete self-disinfection of the nanosheet-modified fabric was achieved within 3 min of irradiation, making the fabrics favorably reusable upon self-disinfection. The nanosheet-modified fabrics maintained the antibacterial efficiency even after 60 washing cycles. Furthermore, the particle filtration efficiency of three-layered surgical masks was found to be significantly improved through incorporation of the MoS2-modified fabric as an additional layer of protective clothing, without compromising the breathability of the masks. The repurposed surgical masks could filter out around 97% of 200 nm particles and 96% of 100 nm particles, thus making them potentially useful for preventing the spread of coronaviruses (120 nm) by trapping them along with antibacterial protection against other airborne pathogens.


Subject(s)
Anti-Infective Agents/chemistry , Disulfides/chemistry , Molybdenum/chemistry , Nanostructures/chemistry , Personal Protective Equipment , Recycling , Anti-Infective Agents/pharmacology , COVID-19/prevention & control , COVID-19/virology , Escherichia coli/drug effects , Escherichia coli/metabolism , Glutathione/chemistry , Humans , Nanostructures/toxicity , Oxidation-Reduction , Particle Size , Reactive Oxygen Species/metabolism , SARS-CoV-2/isolation & purification , Staphylococcus aureus/drug effects , Staphylococcus aureus/metabolism , Sunlight , Temperature
20.
mSphere ; 6(2)2021 03 03.
Article in English | MEDLINE | ID: covidwho-1117328

ABSTRACT

Hand sanitizers have been developed as a convenient means to decontaminate an individual's hands of bacterial pathogens in situations in which soap and water are not available. Yet to our knowledge, no study has compared the antibacterial efficacy of a large collection of hand sanitizers. Using zone of growth inhibition and kill curve assays, we assessed the performance of 46 commercially available hand sanitizers that were obtained from national chain big-box stores, gasoline stations, pharmacies, and boutiques for antibacterial activity toward prototypical Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacterial pathogens. Results revealed substantial variability in the efficacy of many sanitizers evaluated. Formulations following World Health Organization-recommended ingredients (80% ethanol or 75% isopropyl alcohol) or those including benzalkonium chloride as the active principal ingredient displayed excellent antibacterial activity, whereas others exhibited modest or poor activity in the assays performed. Results also revealed that E. coli was generally more susceptible to most sanitizers in comparison to S. aureus and that there was significant strain-to-strain variability in hand sanitizer antimicrobial efficacy regardless of the organism evaluated. Further, tests of a subset of hand sanitizers toward severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) revealed no direct correlation between antibacterial and antiviral performance, with all ethyl alcohol formulations performing equally well and displaying improved activity in comparison to benzalkonium chloride-containing sanitizer. Taken together, these results indicate that there is likely to be substantial variability in the antimicrobial performance of commercially available hand sanitizers, particularly toward bacterial pathogens, and a need to evaluate the efficacy of sanitizers under development.IMPORTANCE In response to the coronavirus disease 2019 (COVID-19) pandemic, hand hygiene has taken on a prominent role in efforts to mitigate SARS-CoV-2 transmission and infection, which has led to a radical increase in the number and types of hand sanitizers manufactured to meet public demand. To our knowledge, no studies have evaluated or compared the antimicrobial performance of hand sanitizers that are being produced under COVID-19 emergency authorization. Tests of 46 commercially available hand sanitizers purchased from national chain brick-and-mortar stores revealed considerable variability in their antibacterial performance toward two bacterial pathogens of immediate health care concern, S. aureus and E. coli Expanded testing of a subset of hand sanitizers revealed no direct correlation between antibacterial performance of individual sanitizers and their activity toward SARS-CoV-2. These results indicate that as the pandemic subsides, there will be a need to validate the antimicrobial efficacy of sanitizers being produced.


Subject(s)
COVID-19/prevention & control , Escherichia coli/drug effects , Hand Sanitizers/pharmacology , SARS-CoV-2/drug effects , Staphylococcus aureus/drug effects , Animals , COVID-19/transmission , Cell Line , Chlorocebus aethiops , Escherichia coli Infections/prevention & control , Escherichia coli Infections/transmission , Hand Disinfection/methods , Humans , Microbial Sensitivity Tests , Staphylococcal Infections/prevention & control , Staphylococcal Infections/transmission , Vero Cells
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