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Toxics Jun 2024This study utilizes (MI) for the first time to investigate the uptake and translocation of chlorpyrifos (CPF; 10 µg g) from soil, introducing a new approach to improve...
This study utilizes (MI) for the first time to investigate the uptake and translocation of chlorpyrifos (CPF; 10 µg g) from soil, introducing a new approach to improve the efficacy of this technique, which includes using biosurfactants ( and ) at 10 CFU/mL to degrade CPF under greenhouse conditions. Moreover, antioxidant enzymes, including superoxide dismutase (SOD) and peroxidase (Prx), and oxidative stress due to hydrogen peroxide (HO) and malondialdehyde (MDA) in MI roots and leaves were evaluated under CPF stress. Our results demonstrated that amending soil with MI and followed by significantly reduced CPF levels in the soil ( > 0.05) and enhanced CPF concentrations in MI roots and leaves after 1, 3, 7, 10, and 14 days of the experiment. Furthermore, CPF showed its longest half-life (t) in soil contaminated solely with CPF, lasting 15.36 days. Conversely, its shortest half-life occurred in soil contaminated with CPF and treated with MI along with , lasting 4.65 days. Soil contaminated with CPF and treated with MI and showed a half-life of 7.98 days. The half-life (t) of CPF-contaminated soil with MI alone was 11.41 days. A batch equilibrium technique showed that is better than for eliminating CPF from soil in In vitro experiments. Notably, CPF-polluted soil treated with coadministration of MI and the tested bacteria improved the activities of SOD and Prx and reduced HO and MDA compared with CPF-polluted soil treated with MI alone. Our findings demonstrated that using and as biosurfactants to augment phytoremediation represents a commendable strategy for enhancing the remediation of CPF contamination in affected sites while reducing the existence of harmful pesticide remnants in crop plants.
PubMed: 38922115
DOI: 10.3390/toxics12060435 -
Veterinary Sciences May 2024The direct effects and antimicrobial activity of synthetic antimicrobial peptides (AMPs) obtained from dogs, including cBD, cBD103, and cCath, against wild-type strain...
The direct effects and antimicrobial activity of synthetic antimicrobial peptides (AMPs) obtained from dogs, including cBD, cBD103, and cCath, against wild-type strain PAO1 and canine keratinocytes were analyzed. Antibacterial effects on planktonic bacteria were assessed by determining the minimum bactericidal concentrations (MBCs) of AMPs and by a time-kill assay. Antibiofilm effects were assessed using the microtiter plate assay. We also evaluated the effects of AMPs on cell cytotoxicity and host immune response induced by stimulating canine epidermal keratinocyte progenitor (CPEK) cells with PAO1 and its LPS. cBD, cBD103, and cCath all exhibited dose-dependent antimicrobial and antibiofilm effects. In particular, 25 μg/mL cBD103 showed rapid bactericidal activity within 60 min and inhibited biofilm formation. In addition, pretreatment with cBD103 (25 µg/mL) and cCath (50 µg/mL) 1 h before stimulation significantly reduced the cytotoxicity of the CPEK cells by PAO1 and LPS-induced IL-6 and TNF-a expressions. cBD had little effect on the response to PAO1 and LPS in the cells. These results indicate the therapeutic potential of AMPs in skin infections. However, further studies on the mechanism of action of AMPs in keratinocytes and clinical trials are needed.
PubMed: 38921982
DOI: 10.3390/vetsci11060235 -
Nanomaterials (Basel, Switzerland) Jun 2024Tetrahedral amorphous carbon (taC) is a hydrogen-free carbon with extensive properties such as hardness, optical transparency, and chemical inertness. taC coatings have...
Tetrahedral amorphous carbon (taC) is a hydrogen-free carbon with extensive properties such as hardness, optical transparency, and chemical inertness. taC coatings have attracted much attention in recent times, as have coatings doped with a noble metal. A known antimicrobial metal agent, silver (Ag), has been used as a dopant in taC, with different Ag concentrations on the Ti64 coupons using a hybrid filtered cathodic vacuum arc (FCVA) and magnetron sputtering system. The physiochemical properties of the coated surface were investigated using spectroscopic and electron microscopy techniques. A doping effect of Ag-taC on biofilm formation was investigated and found to have a significant effect on the bacterial-biofilm-forming bacteria and depending on the concentration of Ag. Further, the effect of coated and uncoated Ag-taC films on a pathogenic bacterium was examined using SEM. The result revealed that the Ag-taC coatings inhibited the biofilm formation of . Therefore, this study demonstrated the possible use of Ag-taC coatings against biofilm-related complications on medical devices and infections from pathogenic bacteria.
PubMed: 38921893
DOI: 10.3390/nano14121017 -
Pathogens (Basel, Switzerland) Jun 2024is a common pathogen associated with recreational water facilities and poses risks to public health. However, data on the prevalence of in tourist destinations like...
is a common pathogen associated with recreational water facilities and poses risks to public health. However, data on the prevalence of in tourist destinations like the Canary Islands, Spain, remain limited. We assessed prevalence in 23 tourist facilities from 2016 to 2019. Compliance with water quality standards was evaluated, and 3962 samples were collected and analyzed. We examined different types of recreational water installations, including outer swimming pools, whirlpools, and cold wells. Of the sampled facilities, 31.2% did not comply with the current legislation's parametric values, mainly due to inadequate disinfectant levels, water temperature, and presence. The prevalence of was 4.8%, comparable to some European countries but lower than others. Cold wells displayed the highest non-compliance rate (89.2%) and yet exhibited a lower prevalence (1.9%) than outer swimming pools and whirlpools. Children's presence did not significantly impact contamination. Chlorine-based disinfectants are more effective than bromine-based ones in controlling . Regional variability in contamination was observed, with Fuerteventura showing lower colonization rates. Disinfectant levels play a critical role in control, and maintaining adequate levels is essential, particularly in bromine-treated installations. Our findings provide valuable insights into the prevalence and distribution of in recreational waters within tourist facilities. Tailored strategies are needed to ensure water safety in different Spanish regions. Continued monitoring and assessment, combined with artificial intelligence and machine learning, will enable the implementation of targeted interventions to protect the health of recreational water users.
PubMed: 38921799
DOI: 10.3390/pathogens13060501 -
Marine Drugs Jun 2024This study aimed to improve the conventional procedure of alginate isolation from the brown seaweed ( L.) biomass and investigate the possibility of further valorization...
This study aimed to improve the conventional procedure of alginate isolation from the brown seaweed ( L.) biomass and investigate the possibility of further valorization of the ethanolic fraction representing the byproduct after the degreasing and depigmentation of biomass. The acid treatment of biomass supported by ultrasound was modeled and optimized regarding the alginate yield using a response surface methodology based on the Box-Behnken design. A treatment time of 30 min, a liquid-to-solid ratio of 30 mL/g, and a treatment temperature of 47 °C were proposed as optimal conditions under which the alginate yield related to the mass of dry biomass was 30.9%. The use of ultrasonic radiation significantly reduced the time required for the acid treatment of biomass by about 4 to 24 times compared to other available conventional procedures. The isolated alginate had an M/G ratio of 1.08, which indicates a greater presence of M-blocks in its structure and the possibility of forming a soft and elastic hydrogel with its use. The chemical composition of the ethanolic fraction including total antioxidant content (293 mg gallic acid equivalent/g dry weight), total flavonoid content (14.9 mg rutin equivalent/g dry weight), contents of macroelements (the highest content of sodium, 106.59 mg/g dry weight), and microelement content (the highest content of boron, 198.84 mg/g dry weight) was determined, and the identification of bioactive compounds was carried out. The results of ultra high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry analysis confirmed the presence of 48 compounds, of which 41 compounds were identified as sugar alcohol, phenolic compounds, and lipids. According to the 2,2-diphenyl-1-picrylhydrazyl assay, the radical scavenging activity of the ethanolic fraction (the half-maximal inhibitory concentration of 42.84 ± 0.81 μg/mL) indicated its strong activity, which was almost the same as in the case of the positive control, synthetic antioxidant butylhydroxytoluene (the half-maximal inhibitory concentration of 36.61 ± 0.79 μg/mL). Gram-positive bacteria (, , and ) were more sensitive to the ethanolic fraction compared to Gram-negative bacteria (, , and ). The obtained results indicated the possibility of the further use of the ethanolic fraction as a fertilizer for plant growth in different species and antifouling agents, applicable in aquaculture.
Topics: Alginates; Laminaria; Antioxidants; Ethanol; Seaweed; Biomass; Flavonoids; Edible Seaweeds
PubMed: 38921591
DOI: 10.3390/md22060280 -
Marine Drugs May 2024Five new naphthalene derivatives dalesconosides A-D, F (-, ), a known synthetic analogue named dalesconoside E (), and eighteen known compounds (-) were isolated from...
Five new naphthalene derivatives dalesconosides A-D, F (-, ), a known synthetic analogue named dalesconoside E (), and eighteen known compounds (-) were isolated from MCZ-18, which is an endophytic fungus obtained from the Chinese mangrove plant . Differing from previously reported naphthalenes, compounds and were bearing a rare ribofuranoside substituted at C-1 and the 5-methyltetrahydrofuran-2,3-diol moiety, respectively. Their structures were determined by detailed nuclear magnetic resonance (NMR) and mass spectroscopic (MS) analyses, while the absolute configurations were established by theoretical electronic circular dichroism (ECD) calculation. Compounds , , - and showed broad ranges of antimicrobial spectrum against five indicator test microorganisms (, Methicillin-resistant , , and ); especially, , and were most potent. The variations in structure and attendant biological activities provided fresh insights concerning structure-activity relationships for the naphthalene derivatives.
Topics: Naphthalenes; Microbial Sensitivity Tests; Structure-Activity Relationship; Magnetic Resonance Spectroscopy; Anti-Bacterial Agents; Candida albicans; Molecular Structure; Rhizophoraceae; Endophytes; Anti-Infective Agents
PubMed: 38921554
DOI: 10.3390/md22060242 -
Journal of Fungi (Basel, Switzerland) May 2024In this study, bacteria residing in the gut of the rice weevils ( L.) (Coleoptera: Curculionidae) feeding on aflatoxin-contaminated corn kernels were isolated and...
In this study, bacteria residing in the gut of the rice weevils ( L.) (Coleoptera: Curculionidae) feeding on aflatoxin-contaminated corn kernels were isolated and evaluated for their ability to suppress and to remove/degrade aflatoxin B1 (AFB1). Four morphologically distinct gut-associated bacterial isolates were isolated and identified as (RWGB1), (RWGB2), (RWGB3), and (RWGB4) based on 16S rRNA gene sequence analysis. These bacterial isolates inhibited growth in the dual culture assay and induced morphological deformities in the fungal hyphae, as confirmed by scanning electron microscopy. All four bacterial isolates were capable of removing AFB1 from the nutrient broth medium. In addition, culture supernatants of these bacterial isolates degraded AFB1, and the degradation of toxin molecules was confirmed by liquid chromatography-mass spectrometry. The bacterial isolates, RWGB1, RWGB2, and RWGB4, were capable of producing antifungal volatile organic compounds that inhibited growth. These results suggest that the bacterial isolates from gut have the potential to bind and/or degrade AFB1. Further research on their application in the food and feed industries could enhance the safety of food and feed production.
PubMed: 38921363
DOI: 10.3390/jof10060377 -
Gels (Basel, Switzerland) Jun 2024A combination of Poloxamer 407 (P407) and hydroxypropyl methylcellulose (HPMC) hydrosols is proposed as an in situ thermo-gelling vehicle for the nasal drug delivery of...
A combination of Poloxamer 407 (P407) and hydroxypropyl methylcellulose (HPMC) hydrosols is proposed as an in situ thermo-gelling vehicle for the nasal drug delivery of chlorhexidine-silver nanoparticles conjugates (SN-CX). Optimization of the formulation was carried out by applying varying ratios of P407 and HPMC in the presence and absence of SN-CX so that gelation would occur in the temperature range of the nasal cavity (30-34 °C). Mechanisms for the observed gelation phenomena were suggested based on viscosimetry, texture analysis, and dynamic light scattering. Tests were carried out for sprayability, washout time, in vitro drug release, ex vivo permeation, and antimicrobial activity. When applied separately, HPMC was found to lower the P407 gelation temperature (T), whereas SN-CX increased it. However, in the presence of HPMC, SN-CX interfered with the P407 micellar organization in a principally contrasting way while leading to an even further decrease in T. SN-CX-loaded nasal formulations composed of P407 16% and HPMC 0.1% demonstrated a desired gelation at 31.9 °C, good sprayability (52.95% coverage of the anterior nasal cavity), mucoadhesion for 70 min under simulated nasal clearance, expedient release and permeation, and preserved anti-infective activity against seasonal Influenza virus and beta-coronavirus, and other pathogens. Our findings suggest that the current development could be considered a potential formulation of a protective nasal spray against respiratory infections.
PubMed: 38920931
DOI: 10.3390/gels10060385 -
MBio Jun 2024encodes the beta-lactamase AmpC, which promotes resistance to beta-lactam antibiotics. Expression of is induced by anhydro-muropeptides (AMPs) released from the...
UNLABELLED
encodes the beta-lactamase AmpC, which promotes resistance to beta-lactam antibiotics. Expression of is induced by anhydro-muropeptides (AMPs) released from the peptidoglycan (PG) cell wall upon beta-lactam treatment. AmpC can also be induced via genetic inactivation of PG biogenesis factors such as the endopeptidase DacB that cleaves PG crosslinks. Mutants in occur in beta-lactam-resistant clinical isolates of , but it has remained unclear why DacB inactivation promotes induction. Similarly, the inactivation of lytic transglycosylase (LT) enzymes such as SltB1 that cut PG glycans has also been associated with induction and beta-lactam resistance. Given that LT enzymes are capable of producing AMP products that serve as inducers, this latter observation has been especially difficult to explain. Here, we show that induction in or mutants requires another LT enzyme called MltG. In , MltG has been implicated in the degradation of nascent PG strands produced upon beta-lactam treatment. Accordingly, in and mutants, we detected the MltG-dependent production of pentapeptide-containing AMP products that are signatures of nascent PG degradation. Our results therefore support a model in which SltB1 and DacB use their PG-cleaving activity to open space in the PG matrix for the insertion of new material. Thus, their inactivation mimics low-level beta-lactam treatment by reducing the efficiency of new PG insertion into the wall, causing the degradation of some nascent PG material by MltG to produce the -inducing signal.
IMPORTANCE
Inducible beta-lactamases like the ampC system of are a common determinant of beta-lactam resistance among gram-negative bacteria. The regulation of is elegantly tuned to detect defects in cell wall synthesis caused by beta-lactam drugs. Studies of mutations causing induction in the absence of drug therefore promise to reveal new insights into the process of cell wall biogenesis in addition to aiding our understanding of how resistance to beta-lactam antibiotics arises in the clinic. In this study, the induction phenotype for mutants lacking a glycan-cleaving enzyme or an enzyme that cuts cell wall crosslinks was used to uncover a potential role for these enzymes in making space in the wall matrix for the insertion of new material during cell growth.
PubMed: 38920394
DOI: 10.1128/mbio.01419-24 -
Journal of Inflammation Research 2024Sepsis-associated acute kidney injury (S-AKI) contributes to high mortality, but it is lack of specific treatments. We aimed to investigate the underlying mechanism of...
PURPOSE
Sepsis-associated acute kidney injury (S-AKI) contributes to high mortality, but it is lack of specific treatments. We aimed to investigate the underlying mechanism of S-AKI and to identify target drugs to alleviate AKI.
METHODS
We establish a stable mouse model of S-AKI by Pseudomonas aeruginosa incision infection. Based on high-throughput sequencing and bioinformatics analysis, we investigated the underlying mechanism and selected the target drug (VX-702) for S-AKI. An in vitro model established by co-cultured of kidney tubular epithelial cell line (TCMK-1) cells with lipopolysaccharide (LPS)-induced leukemic monocyte/macrophage cells (RAW264.7), we explored the effect of VX-702 on S-AKI.
RESULTS
The data showed interleukin (IL)-6 and IL-1β were the hub genes, and the mitogen-activated protein kinase (MAPK) signaling pathway was the main pathway involved in S-AKI. Administration of VX-702 by oral gavage decreased the elevated concentrations of IL-6, IL-1β, serum creatinine, and blood urea nitrogen in mice with S-AKI. Moreover, VX-702 reduced the number of apoptotic cells in damaged kidney tissues. Cell viability was decreased, and the number of apoptotic cells was increased in TCMK-1 cells co-cultured with LPS-induced RAW264.7 cells compared to LPS-induced TCMK-1 cells. VX-702 treatment reversed this effect. VX-702 treatment reduced the levels of phosphorylated p38 MAPK and proinflammatory cytokines in RAW264.7 cells and the supernatant. VX-702 could bind IL-6, IL-1β and MAPK, and affect the binding of IL-1β and its receptor, as demonstrated by molecular docking.
CONCLUSION
VX-702 ameliorated S-AKI by inhibiting the release of proinflammatory cytokines from macrophages, indicating its potential as a novel therapeutic for S-AKI treatment.
PubMed: 38919509
DOI: 10.2147/JIR.S464018