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Search Results (5,475)

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12 pages, 335 KiB  
Review
Poisoning-Induced Acute Kidney Injury: A Review
by Ching-Hsiang Yu, Lan-Chi Huang and Yu-Jang Su
Medicina 2024, 60(8), 1302; https://doi.org/10.3390/medicina60081302 - 12 Aug 2024
Abstract
Acute kidney injury (AKI) is a debilitating, multi-etiological disease that is commonly seen in clinical practice and in the emergency department. In this review, we introduce the definition, symptoms, and causes of poisoning-related AKI; we also discuss its mechanisms, risk factors, and epidemiology, [...] Read more.
Acute kidney injury (AKI) is a debilitating, multi-etiological disease that is commonly seen in clinical practice and in the emergency department. In this review, we introduce the definition, symptoms, and causes of poisoning-related AKI; we also discuss its mechanisms, risk factors, and epidemiology, as well as elaborate on the relevant laboratory tests. Subsequently, we discuss the treatment strategies for toxin- and substance-related AKI caused by Glafenin, antimicrobial agents, lithium, contrast media, snake venom, herbicides, ethylene glycol, synthetic cannabinoids, cocaine, heroin, and amphetamines. Finally, for a comprehensive overview of poisoning-related AKI, we review the management, prevention, and outcomes of this condition. Full article
(This article belongs to the Special Issue Early Detection and Clinical Treatment of Acute Kidney Injury)
16 pages, 1908 KiB  
Article
Synthesis of Second-Generation Analogs of Temporin-SHa Peptide Having Broad-Spectrum Antibacterial and Anticancer Effects
by Arif Iftikhar Khan, Shahzad Nazir, Muhammad Nadeem ul Haque, Rukesh Maharjan, Farooq-Ahmad Khan, Hamza Olleik, Elise Courvoisier-Dezord, Marc Maresca and Farzana Shaheen
Antibiotics 2024, 13(8), 758; https://doi.org/10.3390/antibiotics13080758 (registering DOI) - 11 Aug 2024
Viewed by 317
Abstract
Antimicrobial peptides (AMPs) are a promising class of therapeutic alternatives with broad-spectrum activity against resistant pathogens. Small AMPs like temporin-SHa (1) and its first-generation analog [G10a]-SHa (2) possess notable efficacy against Gram-positive and Gram-negative bacteria. In an effort to [...] Read more.
Antimicrobial peptides (AMPs) are a promising class of therapeutic alternatives with broad-spectrum activity against resistant pathogens. Small AMPs like temporin-SHa (1) and its first-generation analog [G10a]-SHa (2) possess notable efficacy against Gram-positive and Gram-negative bacteria. In an effort to further improve this antimicrobial activity, second-generation analogs of 1 were synthesised by replacing the natural glycine residue at position-10 of the parent molecule with atypical amino acids, such as D-Phenylalanine, D-Tyrosine and (2-Naphthyl)-D-alanine, to study the effect of hydrophobicity on antimicrobial efficacy. The resultant analogs (36) emerged as broad-spectrum antibacterial agents. Notably, the [G10K]-SHa analog (4), having a lysine substitution, demonstrated a 4-fold increase in activity against Gram-negative (Enterobacter cloacae DSM 30054) and Gram-positive (Enterococcus faecalis DSM 2570) bacteria relative to the parent peptide (1). Among all analogs, [G10f]-SHa peptide (3), featuring a D-Phe substitution, showed the most potent anticancer activity against lung cancer (A549), skin cancer (MNT-1), prostate cancer (PC-3), pancreatic cancer (MiaPaCa-2) and breast cancer (MCF-7) cells, achieving an IC50 value in the range of 3.6–6.8 µM; however, it was also found to be cytotoxic against normal cell lines as compared to [G10K]-SHa (4). Peptide 4 also possessed good anticancer activity but was found to be less cytotoxic against normal cell lines as compared to 1 and 3. These findings underscore the potential of second-generation temporin-SHa analogs, especially analog 4, as promising leads to develop new broad-spectrum antibacterial and anticancer agents. Full article
(This article belongs to the Section Antimicrobial Peptides)
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Figure 1
<p>UPLC profiles of the synthesised peptides; (<b>A</b>) temporin-SHa; (<b>B</b>) [G10a]-SHa; (<b>C</b>) [G10f]-SHa; (<b>D</b>) [G10y]-SHa; (<b>E</b>) [G10n]-SHa and (<b>F</b>) [G10K]-SHa.</p>
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<p>Circular dichroism of temporin SHa, [G10a]-Sha, and newly synthesised second-generation analogs of [G10a]-SHa in 20 mM SDS.</p>
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<p>Antiproliferative effect of SHa derivatives on human cancer cells. The antiproliferative effect of SHa derivatives was measured on dividing cancer cells, as explained in <a href="#sec4-antibiotics-13-00758" class="html-sec">Section 4</a> (Temporin-SHa (<b>1</b>): open black circles, [G10a]-SHa (<b>2</b>): closed red circles, [G10f]-SHa (<b>2</b>): closed green squares, [G10K]-SHa (<b>3</b>): closed black diamonds, [G10n]-SHa (<b>4</b>): inverted open purple triangles, [G10y]-SHa (<b>5</b>): closed blue triangles). Results are expressed as a percentage of cell proliferation, the untreated cells giving 100% proliferation (means ± SD, <span class="html-italic">n</span> = 3).</p>
Full article ">Figure 4
<p>Antiproliferative effect of SHa derivatives on human normal/non cancerous cells. The antiproliferative effect of SHa derivatives was measured on dividing normal cells, as explained in <a href="#sec4-antibiotics-13-00758" class="html-sec">Section 4</a> (temporin-SHa (<b>1</b>): open black circles, [G10a]-SHa (<b>2</b>): closed red circles, [G10f]-SHa (<b>2</b>): closed green squares, [G10K]-SHa (<b>3</b>): closed black diamonds, [G10n]-SHa (<b>4</b>): inverted open purple triangles, [G10y]-SHa (<b>5</b>): closed blue triangles). Results are expressed as a percentage of cell proliferation, the untreated cells giving 100% proliferation (means ± SD, <span class="html-italic">n</span> = 3).</p>
Full article ">Figure 5
<p>Cytotoxic effect of SHa derivatives on human normal and cancer lung cells. The cytotoxic effect of temporin-SHa (<b>1</b>) derivatives was measured on confluent/non-dividing cells, as explained in <a href="#sec4-antibiotics-13-00758" class="html-sec">Section 4</a>, using human lung cancer (A549 cells) and normal cells (BEAS-2B cells); ([G10a]-SHa (<b>2</b>): closed red circles, [G10f]-SHa (<b>2</b>): closed green squares, [G10K]-SHa (<b>3</b>): closed black diamonds, [G10n]-SHa (<b>4</b>): inverted open purple triangles, [G10y]-SHa (<b>5</b>): closed blue triangles). Results are expressed as a percentage of cell proliferation, the untreated cells giving 100% proliferation (means ± SD, <span class="html-italic">n</span> = 3).</p>
Full article ">Scheme 1
<p>Synthesis and structure of temporin-SHa (<b>1</b>), its first-generation [G10a]-SHa peptide (<b>2</b>) and newly synthesised second-generation analogs (<b>3</b>–<b>6</b>).</p>
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26 pages, 4780 KiB  
Article
Synthesis, Structural Properties and Biological Activities of Novel Hydrazones of 2-, 3-, 4-Iodobenzoic Acid
by Izabela Czyżewska, Liliana Mazur, Anna Biernasiuk, Anna Hordyjewska and Łukasz Popiołek
Molecules 2024, 29(16), 3814; https://doi.org/10.3390/molecules29163814 (registering DOI) - 11 Aug 2024
Viewed by 389
Abstract
Nowadays, searching for novel antimicrobial agents is crucial due to the increasing number of resistant bacterial strains. Moreover, cancer therapy is a major challenge for modern medicine. Currently used cytostatics have a large number of side effects and insufficient therapeutic effects. Due to [...] Read more.
Nowadays, searching for novel antimicrobial agents is crucial due to the increasing number of resistant bacterial strains. Moreover, cancer therapy is a major challenge for modern medicine. Currently used cytostatics have a large number of side effects and insufficient therapeutic effects. Due to the above-mentioned facts, we undertook research to synthesize novel compounds from the acylhydrazone group aimed at obtaining potential antimicrobial and anticancer agents. As a starting material, we employed hydrazides of 2-, 3- or 4-iodobenzoic acid, which gave three series of acylhydrazones in the condensation reaction with various aldehydes. The chemical structure of all obtained compounds was confirmed by IR, 1H NMR, and 13C NMR. The structure of selected compounds was determined by single-crystal X-ray diffraction analysis. Additionally, all samples were characterized using powder X-ray diffraction. The other issue in this research was to examine the possibility of the solvent-free synthesis of compounds using mechanochemical methods. The biological screening results revealed that some of the newly synthesized compounds indicated a beneficial antimicrobial effect even against MRSA—the methicillin-resistant Staphylococcus aureus ATCC 43300 strain. In many cases, the antibacterial activity of synthesized acylhydrazones was equal to or better than that of commercially available antibacterial agents that were used as reference substances in this research. Significantly, the tested compounds do not show toxicity to normal cell lines either. Full article
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Figure 1
<p>PXRD patterns of compound <b>13</b>: (<b>a</b>) simulated from the SCXRD data; (<b>b</b>) experimental after synthesis from solution; (<b>c</b>–<b>e</b>) experimental after liquid-assisted grinding (LAG) for 30, 60 and 90 min, respectively, using ethanol as a solvent; (<b>f</b>) experimental after LAG for 90 min using acetonitrile.</p>
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<p>Perspective view of the molecules constituting the asymmetric part in crystals <b>13</b>, <b>13</b>∙<b>ACN</b>, <b>20</b> and <b>26a</b> with the atom-numbering scheme. Thermal ellipsoids are drawn at the 50% probability level. Dashed lines indicate the hydrogen bonds.</p>
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<p>Molecular overlay of the conformers found in: (<b>a</b>) polymorphic modifications <b>26a</b> (red line), <b>26b</b> (green line) and <b>26c</b> (dark blue line); (<b>b</b>) unsolvated crystal <b>13</b> (molecule 13A—blue line, molecule 13B—green line) and its solvate <b>13</b>∙<b>ACN</b> (pink line).</p>
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<p>Part of the crystal structure of <b>13</b>·<b>ACN</b> in view along the <span class="html-italic">a</span> axis, showing the formation of channels filled in by the solvent molecules.</p>
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<p>Part of the crystal structure of <b>9</b> showing (<b>a</b>) supramolecular chains stabilized via strong N1–H1n∙∙∙O1A/N1A–H1nA∙∙∙O1 (x, y + 1, <span class="html-italic">z</span>) hydrogen bonds and weak C–H∙∙∙O/π interactions; (<b>b</b>) crystal packing viewed along the <span class="html-italic">b</span> axis with marked 2D layer parallel to the (−102) crystallographic plane. Molecules <b>9-A</b> and <b>9-B</b> are marked in green and blue, respectively. Dashed lines indicate hydrogen bonds.</p>
Full article ">Figure 6
<p>(<b>a</b>) Part of the crystal structure of <b>26a</b> showing hydrogen-bonding motifs; (<b>b</b>) crystal packing in <b>26a</b> viewed along the <span class="html-italic">b</span> axis; (<b>c</b>) crystal packing in <b>26b</b> viewed down the <span class="html-italic">a</span> axis; (<b>d</b>) hydrogen-bonding patterns in crystal <b>26c</b>, (<b>e</b>) part of the crystal structure of <b>26c</b> in view along the <span class="html-italic">a</span> axis. Dashed lines indicate inter- and intramolecular interactions.</p>
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<p>Synthesis of the hydrazides of 2-, 3- or 4-iodobenzoic acid.</p>
Full article ">Scheme 2
<p>Synthesis of the acylhydrazones of 2-, 3- or 4-iodobenzoic acid.</p>
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14 pages, 902 KiB  
Article
Solid-State Fermentation for Phenolic Compounds Recovery from Mexican Oregano (Lippia graveolens Kunth) Residual Leaves Applying a Lactic Acid Bacteria (Leuconostoc mesenteroides)
by Israel Bautista-Hernández, Ricardo Gómez-García, Cristóbal N. Aguilar, Guillermo C. G. Martínez-Ávila, Cristian Torres-León and Mónica L. Chávez-González
Agriculture 2024, 14(8), 1342; https://doi.org/10.3390/agriculture14081342 - 11 Aug 2024
Viewed by 457
Abstract
The Mexican oregano by-products are a source of bioactive molecules (polyphenols) that could be extracted using solid-state fermentation (SSF). This study fermented the by-products via SSF (120 h) with a lactic acid bacteria (LAB) Leuconostoc mesenteroides. Sequentially, a bioactive and chemical determination [...] Read more.
The Mexican oregano by-products are a source of bioactive molecules (polyphenols) that could be extracted using solid-state fermentation (SSF). This study fermented the by-products via SSF (120 h) with a lactic acid bacteria (LAB) Leuconostoc mesenteroides. Sequentially, a bioactive and chemical determination was made according to the phenolic content, antioxidant activity (DPPH/FRAP), bioactive properties (α-amylase inhibition and antimicrobial activity against Escherichia coli), and chemical composition (HPLC-MS). The results showed that the total phenolics and flavonoid content, as well as the antioxidant activity, increased (0.60, 2.55, and 3.01 times, respectively) during the SSF process compared with unfermented material. Also, the extracts showed antimicrobial activity against E. coli and α-amylase inhibition. These inhibitory results could be attributed to bioactive compounds identified via HPLC, such as gardenin B, trachelogenin, ferulic acid, and resveratrol 3-O-glucoside. Therefore, the application of L. mesenteroides under SSF on oregano by-products comprises an eco-friendly strategy for their valorization as raw materials for the recovery of phenolic compounds that could be natural alternatives against synthetic antioxidant and antimicrobial agents, promoting a more circular and sustainable supply system within the oregano industry. Full article
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Figure 1
<p>General process diagram of bioactive activity and chemical evaluation of <span class="html-italic">Lippia graveolens</span> by-product valorization through SSF process.</p>
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<p>Polyphenolic compounds concentration in fermentative extracts obtained from SSF process using <span class="html-italic">L. mesenteroides</span>. (<b>A</b>) Total polyphenolic content (TPC) and (<b>B</b>) total flavonoid content (TFC). Different letters show significant differences (α = 0.05).</p>
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<p>Antioxidant activity of fermentative extracts via the SSF process using <span class="html-italic">L. mesenteroides</span>; (<b>A</b>) FRAP assay and (<b>B</b>) DPPH<sup>●</sup> assay. The different letters show significant differences (α = 0.05).</p>
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10 pages, 2807 KiB  
Communication
Long-Term Stability and Efficacy of NCT Solutions
by Gabriel J. Staudinger, Zach M. Thomas, Sarah E. Hooper, Jeffrey F. Williams and Lori I. Robins
Int. J. Mol. Sci. 2024, 25(16), 8745; https://doi.org/10.3390/ijms25168745 (registering DOI) - 10 Aug 2024
Viewed by 292
Abstract
To realize the potential for the use of N-chlorotaurine (NCT) in healthcare, a better understanding of the long-term stability of the compound in water is needed. An array of analytical procedures is required that can measure changes in NCT concentration over time [...] Read more.
To realize the potential for the use of N-chlorotaurine (NCT) in healthcare, a better understanding of the long-term stability of the compound in water is needed. An array of analytical procedures is required that can measure changes in NCT concentration over time and allow for the detection and identification of contaminants and likely degradation end products. We used UV-Vis and NMR spectroscopy, HPLC, and LCMS to establish the stability of NCT in solutions subjected to prolonged ambient and elevated temperatures. Stability proved to be dependent on concentration with half-lives of ~120 days and ~236 days for 1% and 0.5% solutions of NCT at ~20 °C. Regardless of initial pH, all solutions shifted toward and maintained a pH of ~8.3 at 20 °C and 40 °C. NCT at 500 µg/mL and 250 µg /mL inhibited biofilm formation by Pseudomonas aeruginosa and Staphylococcus aureus but did not disperse established biofilms. NCT exposure to the biofilms had profound effects on the viability of both bacteria, reducing live organisms by >90%. Exposure of Interleukin-6 (IL-6) to 11 µM NCT reduced the binding of IL-6 to an immobilized specific antibody by ~48%, which is 5× the amount required for HOCl to bring about the same effect in this test system. Our data demonstrate the potency of the compound as an antimicrobial agent with potential benefits in the management of infected chronic wounds and suggest that NCT may contribute to anti-inflammatory processes in vivo by direct modification of cytokine mediators. Full article
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<p>UV-Vis spectroscopy, IR spectroscopy, and <sup>13</sup>C NMR spectroscopy of NCT. (<b>A</b>) UV–Visible spectroscopy wavelength scans of NCT (blue), N,N-dichlorotaurine (black), and taurine (teal). (<b>B</b>) IR spectrum of taurine (black) and NCT (blue). (<b>C</b>) <sup>13</sup>C NMR spectrum of NCT (black, singlets at 50.74 and 48.96 ppm) and taurine (gray, singlets at 47.42 and 35.38 ppm).</p>
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<p>HPLC and LCMS analysis of NCT. (<b>A</b>) HPLC spectrum of NCT (1 mg/mL) at 252 nm. The area under the curve was calculated and purity was determined to be &gt;95%. (<b>B</b>) UV-Vis wavelength trace of NCT detected by the LCMS. (<b>C</b>) TIC data for the corresponding LCMS peak at 252 nm. (<b>D</b>) MS data for the corresponding TIC peak at 252 nm.</p>
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<p>Stability of NCT solutions at 1%, 0.5%, and 0.25% at ambient and elevated temperatures. (<b>A</b>) Starting pH 9.5 at room temperature. (<b>B</b>) Starting pH 7 at 40 °C. (<b>C</b>) Starting pH 8 at 40 °C. (<b>D</b>) Starting pH 9.5 at 40 °C. Each condition was repeated three times. Additional stability data for these trials are available in <a href="#app1-ijms-25-08745" class="html-app">Figure S1</a>. All 1% solutions are in blue; 0.5% in green; and 0.25% in black. A single-factor ANOVA was used to test for differences in starting pH values and for differences in concentrations.</p>
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<p>pH of NCT solutions at 1% (circle), 0.5% (square), and 0.25% (triangle). (<b>A</b>) Solutions starting at a pH value of 7. (<b>B</b>) Solutions starting at a pH value of 8. (<b>C</b>) Solutions starting at a pH value of 9.5. Additional pH data for the three trials are available in <a href="#app1-ijms-25-08745" class="html-app">Figure S2</a>.</p>
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<p>ELISA test results for IL-6 binding to an IL-6 specific antibody after treatment with concentrations of NCT ranging from 0 to 2.76 mM. A single-factor ANOVA was used to test for differences in binding at all concentrations of NCT tested.</p>
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<p>Viability of remaining <span class="html-italic">P. aeruginosa</span> (black) and <span class="html-italic">S. aureus</span> (gray) biofilm biomass after treatment with various NCT concentrations. Significant reductions in viability were calculated using ANOVA and Tukey’s post hoc analysis. The significant threshold concentrations were 0.004% for <span class="html-italic">S. aureus</span> and 0.06% for <span class="html-italic">P. aeruginosa</span>.</p>
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14 pages, 3333 KiB  
Article
Discovery of Antibacterial Compounds with Potential Multi-Pharmacology against Staphylococcus Mur ligase Family Members by In Silico Structure-Based Drug Screening
by Mio Teshima, Kohei Monobe, Saya Okubo and Shunsuke Aoki
Molecules 2024, 29(16), 3792; https://doi.org/10.3390/molecules29163792 - 10 Aug 2024
Viewed by 279
Abstract
Staphylococcus aureus (S. aureus) is a major bacterial infection in humans, leading to severe disease and causing death. The stagnation of antibiotic development in recent decades has made it difficult to combat drug-resistant infections. In this study, we performed an in [...] Read more.
Staphylococcus aureus (S. aureus) is a major bacterial infection in humans, leading to severe disease and causing death. The stagnation of antibiotic development in recent decades has made it difficult to combat drug-resistant infections. In this study, we performed an in silico structure-based drug screening (SBDS) targeting the S. aureus MurE (saMurE) enzyme involved in cell wall synthesis of S. aureus. saMurE is an enzyme that is essential for the survival of S. aureus but not present in humans. SBDS identified nine saMurE inhibitor candidates, Compounds 19, from a structural library of 154,118 compounds. Among them, Compound 2 showed strong antibacterial activity against Staphylococcus epidermidis (S. epidermidis) used as a model bacterium. Amino acid sequence homology between saMurE and S. epidermidis MurE is 87.4%, suggesting that Compound 2 has a similar inhibitory effect on S. aureus. Compound 2 showed an IC50 value of 301 nM for S. epidermidis in the dose-dependent growth inhibition assay. Molecular dynamics simulation showed that Compound 2 binds stably to both S. aureus MurD and S. aureus MurF, suggesting that it is a potential multi-pharmacological pharmacological inhibitor. The structural and bioactivity information of Compound 2, as well as its potential multiple-target activity, could contribute to developing new antimicrobial agents based on MurE inhibition. Full article
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Graphical abstract

Graphical abstract
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<p>saMurE inhibitor screening strategy.</p>
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<p>Growth inhibitory effect of Compounds <b>1</b>–<b>9</b> on bacteria (<span class="html-italic">S. epidermidis</span>). A total of 0.3% DMSO and 100 μM ampicillin (AMP) were used as samples for comparison. Compounds <b>1</b>–<b>9</b> (100 μM). The vertical axis is the mean +/− SEM of the results of four independent experiments. Dunnett’s test: ****; <span class="html-italic">p</span> &lt; 0.0001; **; <span class="html-italic">p</span> &lt; 0.0021; *; <span class="html-italic">p</span> &lt; 0.0332; n.s. = not significant.</p>
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<p>Determination of 50% growth inhibition concentration against bacteria (<span class="html-italic">S. epidermidis</span>). The vertical axis shows the relative bacterial growth rate. The horizontal axis shows the molar concentration of Compound <b>2</b>.</p>
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<p>MDS results for the saMurE–Compound <b>2</b> complex: (<b>A</b>) Transition of ligand RMSD value (nm). Ligand RMSD values were calculated by comparison with the post-equilibration pose. (<b>B</b>) Radius (nm) of gyration during MDS. (<b>C</b>) Number of intermolecular hydrogen bonds.</p>
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<p>ProLIF analysis for the saMurE–Compound <b>2</b> interaction: (<b>A</b>) Interacting residues throughout the MDS timeframe. In the screening process, the piperazine group of Compound <b>2</b> is protonated. (<b>B</b>) A major (≥60% probability of presence) interaction residue group was observed throughout the entire period.</p>
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<p>Toxicity verification of Compound <b>2</b> on mammalian-derived cells: (<b>A</b>) COS-7 cells; (<b>B</b>) HepG2 cells. Negative control was 0.3% DMSO and positive control was 50 μM triclosan (TCS). Concentration of Compound <b>2</b> was 100 μM. Dunnett’s test: ***; <span class="html-italic">p</span> &lt; 0.0002; n.s. = not significant.</p>
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<p>MDS results for saMur ligase–Compound <b>2</b> complexes: (<b>A</b>) ligand RMSD values (nm); (<b>B</b>) radius (nm) of gyration during MDS; (<b>C</b>) number of intermolecular hydrogen bonds. saMurC (black), saMurD (red), saMurF (green).</p>
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13 pages, 2670 KiB  
Review
Advances in Regenerative and Reconstructive Medicine in the Prevention and Treatment of Bone Infections
by Leticia Ramos Dantas, Gabriel Burato Ortis, Paula Hansen Suss and Felipe Francisco Tuon
Biology 2024, 13(8), 605; https://doi.org/10.3390/biology13080605 (registering DOI) - 10 Aug 2024
Viewed by 198
Abstract
Reconstructive and regenerative medicine are critical disciplines dedicated to restoring tissues and organs affected by injury, disease, or congenital anomalies. These fields rely on biomaterials like synthetic polymers, metals, ceramics, and biological tissues to create substitutes that integrate seamlessly with the body. Personalized [...] Read more.
Reconstructive and regenerative medicine are critical disciplines dedicated to restoring tissues and organs affected by injury, disease, or congenital anomalies. These fields rely on biomaterials like synthetic polymers, metals, ceramics, and biological tissues to create substitutes that integrate seamlessly with the body. Personalized implants and prosthetics, designed using advanced imaging and computer-assisted techniques, ensure optimal functionality and fit. Regenerative medicine focuses on stimulating natural healing mechanisms through cellular therapies and biomaterial scaffolds, enhancing tissue regeneration. In bone repair, addressing defects requires advanced solutions such as bone grafts, essential in medical and dental practices worldwide. Bovine bone scaffolds offer advantages over autogenous grafts, reducing surgical risks and costs. Incorporating antimicrobial properties into bone substitutes, particularly with metals like zinc, copper, and silver, shows promise in preventing infections associated with graft procedures. Silver nanoparticles exhibit robust antimicrobial efficacy, while zinc nanoparticles aid in infection prevention and support bone healing; 3D printing technology facilitates the production of customized implants and scaffolds, revolutionizing treatment approaches across medical disciplines. In this review, we discuss the primary biomaterials and their association with antimicrobial agents. Full article
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<p>A diagram demonstrating multiple options for doping bone grafts or polymers for 3D printing using metal nanoparticles or antibiotics in bone reconstruction.</p>
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<p>Silver nanoparticles on bone surface used for orthopedic graft.</p>
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<p>Antibiotic-impregnated PLA models with <span class="html-italic">Staphylococcus aureus</span> test.</p>
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<p>Implants with PLA impregnated with antibiotics tested during surgery for hip replacement.</p>
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15 pages, 6620 KiB  
Article
Lactoferrin Affects the Viability of Bacteria in a Biofilm and the Formation of a New Biofilm Cycle of Mannheimia haemolytica A2
by Lucero Ruiz-Mazón, Gerardo Ramírez-Rico and Mireya de la Garza
Int. J. Mol. Sci. 2024, 25(16), 8718; https://doi.org/10.3390/ijms25168718 (registering DOI) - 9 Aug 2024
Viewed by 275
Abstract
Respiratory diseases in ruminants are responsible for enormous economic losses for the dairy and meat industry. The main causative bacterial agent of pneumonia in ovine is Mannheimia haemolytica A2. Due to the impact of this disease, the effect of the antimicrobial protein, bovine [...] Read more.
Respiratory diseases in ruminants are responsible for enormous economic losses for the dairy and meat industry. The main causative bacterial agent of pneumonia in ovine is Mannheimia haemolytica A2. Due to the impact of this disease, the effect of the antimicrobial protein, bovine lactoferrin (bLf), against virulence factors of this bacterium has been studied. However, its effect on biofilm formation has not been reported. In this work, we evaluated the effect on different stages of the biofilm. Our results reveal a decrease in biofilm formation when bacteria were pre-incubated with bLf. However, when bLf was added at the start of biofilm formation and on mature biofilm, an increase was observed, which was visualized by greater bacterial aggregation and secretion of biofilm matrix components. Additionally, through SDS-PAGE, a remarkable band of ~80 kDa was observed when bLf was added to biofilms. Therefore, the presence of bLf on the biofilm was determined through the Western blot and Microscopy techniques. Finally, by using Live/Dead staining, we observed that most of the bacteria in a biofilm with bLf were not viable. In addition, bLf affects the formation of a new biofilm cycle. In conclusion, bLf binds to the biofilm of M. haemolytica A2 and affects the viability of bacteria and the formation a new biofilm cycle. Full article
(This article belongs to the Special Issue New Insights into Lactoferrin)
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<p><b>Viability of <span class="html-italic">M. haemolytica</span> A2 with bLf.</b> <span class="html-italic">M. haemolytica</span> incubated with different concentrations of bLf at different times. The concentrations of 3.5 and 6 μM were sub-inhibitory until the 48th hour of incubation. Concentrations of 8 and 9 μM were inhibitory since they showed a significant difference regarding bacteria grown without bLf (NT) <span class="html-italic">p</span> &lt; 0.05. Representative results of three independent experiments.</p>
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<p><b>Inhibitory and stimulatory effect of bLf on the biofilm formation of <span class="html-italic">M. haemolytica</span> A2.</b> (<b>a</b>) Bacteria were pre-incubated overnight with 3.5 and 6 μM bLf, then transferred to a microplate for biofilm formation; after 48 h, bacteria that had previous contact with bLf were no longer able to form a biofilm as bacteria without treatment do, since there was a reduction of 38 and 51% with incubation of 3.5 and 6 μM bLf, respectively. (<b>b</b>) Bacteria culture was transferred to a microplate for biofilm formation, and 3.5 and 6 μM bLf were added; after 48 h, an increase in biofilm was observed compared to the biofilm of untreated bacteria. These results were dependent on bLf concentration, as a significant difference was obtained between the different bLf concentrations used; bovine Lf alone was added to the microplate without biofilm to discard adherence of bLf to the microplate. Statistically significant differences between ratios are indicated (* <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, *** <span class="html-italic">p</span> &lt; 0.001). Representative results of three independent experiments.</p>
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<p><b>Stimulatory effect of bLf on a mature biofilm of <span class="html-italic">M. haemolytica</span> A2</b>. Bovine Lf (3.5 and 6 μM) was added to a 48 h biofilm of <span class="html-italic">M. haemolytica</span> A2. After 24 h, an increase in biofilm with bLf was observed, compared to a biofilm of bacteria with no treatment. These results were dependent on bLf concentration, as a significant difference was obtained between both bLf concentrations used, respectively; Lf alone was added to the microplate without biofilm to discard adherence of bLf to the microplate. Statistically significant differences between ratios are indicated (* <span class="html-italic">p</span> &lt; 0.05, *** <span class="html-italic">p</span> &lt; 0.001). Representative results of three independent experiments.</p>
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<p><b>Biofilm observation under a Scanning Electron Microscope.</b> Biofilm of <span class="html-italic">M. haemolytica</span> A2 with no treatment (NT) at a magnification of 500× (<b>a</b>) and 10,000× (<b>b</b>). The blank space shows the surface to which it is attached; biofilm with 3.5 μM bLf at a magnification of 500× (<b>c</b>) and 10,000× (<b>d</b>). The biofilm was observed to a greater extent and structures on the bacterial surface were noticed, compared to the biofilm with no treatment (red arrow). Biofilm with 6 μM bLf at a magnification of 500× (<b>e</b>) and 10,000× (<b>f</b>). A remarkable increase in biofilm was observed, indicated by the lack of blank space, as well as an increase in the structures on the bacterial surface and a mesh-like coating (red arrows). Representative images of three independent samples.</p>
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<p><b>Proteins and carbohydrates of the biofilm matrix of <span class="html-italic">M. haemolytica</span> A2, observed under a laser confocal microscope.</b> Images show proteins of the biofilm without bLf (NT) with the Sypro Ruby stain (<b>a</b>–<b>c</b>), and carbohydrates of the biofilm with the Red Texas stain (<b>d</b>–<b>f</b>); proteins and carbohydrates from biofilm incubated with 3.5 μM bLf (<b>b</b>,<b>e</b>) and 6 μM bLf (<b>c</b>,<b>f</b>) are shown. The intensity of the fluorescence (white arrows) in the biofilms with bLf shows a major amount of these components compared to the biofilm with no treatment. Image magnification: 40×. Representative images of three independent samples.</p>
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<p><b>Results of 10% SDS-PAGE of <span class="html-italic">M. haemolytica</span> A2 biofilm proteins incubated or unincubated with bLf.</b> The protein pattern was analyzed by SDS-PAGE, using samples of 48 h biofilms with or without 3.5 and 6 μM bLf. With this assay, we did not observe differences in the biofilm pattern when bLf was added, in comparison to the biofilm without bLf. In addition, a remarkable band corresponding to the molecular weight of bLf (~80 kDa) was observed where it was added (red asterisks). Representative results of three independent samples.</p>
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<p><b>Presence of bLf in the biofilm of <span class="html-italic">M. haemolytica</span> A2 shown through laser confocal microscopy and Western blot</b>. Images show the distribution of bLf labeled with FITC (green fluorescence) at 3.5 μM (<b>b</b>) and 6 μM (<b>c</b>) throughout the biofilm of <span class="html-italic">M. haemolytica</span> A2, and a negative control where FITC-bLf was added to the plate with no biofilm (<b>a</b>). Western blot using anti-bLf in a biofilm without bLf (NT), with 3.5 or 6 μM bLf and a secondary anti-rabbit-HRP antibody alone as a negative control (<b>d</b>). Representative results of three independent samples.</p>
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<p><b>Bovine Lf affects the viability of bacteria in biofilms with bLf, visualized by Confocal Laser Microscopy.</b> CLM images of bacteria in biofilm for 48 h without bLf (NT) (<b>a</b>–<b>c</b>) and with 3.5 (<b>d</b>–<b>f</b>) or 6 μM (<b>g</b>–<b>i</b>) bLf, showing live bacteria with the Sypro stain (<b>a</b>,<b>d</b>,<b>g</b>) and dead bacteria with the propidium iodide exclusion stain (<b>b</b>,<b>e</b>,<b>h</b>). The merge shows a greater distribution of dead bacteria (visualized by the distribution of yellow fluorescence) in a biofilm with bLf (<b>f</b>,<b>i</b>) than in a biofilm without treatment, where a greater distribution of live bacteria was observed (visualized by the distribution of green fluorescence) (<b>c</b>). Representative images of three independent samples.</p>
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<p><b>Formation of a new biofilm cycle of <span class="html-italic">M. haemolytica</span> A2.</b> Bacteria of a 48 h biofilm with or without bLf were transferred to a new microplate to form a new biofilm cycle for another 48 h without bLf. A decrease in biofilm formation was observed in bacteria from a biofilm with bLf compared to bacteria from a biofilm with no treatment. Statistically significant differences between ratios are indicated (** <span class="html-italic">p</span> &lt; 0.01, *** <span class="html-italic">p</span> &lt; 0.001). Representative results of three independent experiments.</p>
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15 pages, 4057 KiB  
Article
Natural Dyeing and Antimicrobial Functionalization of Wool Fabrics Dyed with Chinese Dragon Fruit Extract to Enhance Sustainable Textiles
by Mohmadarslan Kutubuddin Sadannavar, Aravin Periyasamy, Syed Rashedul Islam, Faizan Shafiq, Xue Dong and Tao Zhao
Sustainability 2024, 16(16), 6832; https://doi.org/10.3390/su16166832 - 9 Aug 2024
Viewed by 355
Abstract
Recently, the natural dyeing process has achieved great importance in the textile wet processing industry due to its clean dyeing, eco-friendliness, and nontoxicity in nature. In the above research project, a unique natural dye extracted from dragon fruit was applied to wool fabric [...] Read more.
Recently, the natural dyeing process has achieved great importance in the textile wet processing industry due to its clean dyeing, eco-friendliness, and nontoxicity in nature. In the above research project, a unique natural dye extracted from dragon fruit was applied to wool fabric using various mordanting agents to encourage the use of natural dyes and lessen the negative environmental effects caused by synthetic dyeing. The color characteristics (K/S), fastness properties, Fourier transform infrared spectroscopy (FTIR), absorption spectra, and thermal and ultraviolet (UV) resistance of the extracted dye and dyed wool samples were tested and characterized. The K/S values of the dyed wool fabrics were between 5.75 and 13.29. The color fastness ratings obtained from the dyed wool fabric were found to be between good and excellent. Hence, the overall results proved that the novel natural dye obtained from dragon fruit can be utilized for dyeing wool material for the production of eco-friendly and sustainable antimicrobial textiles. Full article
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<p>Color shades obtained by wool samples after mordanting, dyeing, and control sample.</p>
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<p>SEM, EDX, and mapping images of (<b>a</b>) undyed wool, (<b>b</b>) wool dyed without mordant, and (<b>c</b>–<b>e</b>) wool dyed with different mordant, (<b>f</b>) carbon mapping, (<b>g</b>) nitrogen mapping, (<b>h</b>) oxygen mapping, and (<b>i</b>) mixed mapping.</p>
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<p>FTIR spectra of raw wool, natural dye extracted from dragon fruit, wool dyed without mordant, wool dyed with copper sulfate mordant, wool dyed with potassium dichromate mordant, and wool dyed with tin chloride mordant.</p>
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<p>Complex reaction mechanism of wool–potassium dichromate mordant for extracted natural dye from dragon fruit.</p>
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<p>Complex reaction mechanism of wool–copper sulfate mordant for natural dye extracted from dragon fruit.</p>
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<p>Complex reaction mechanism of wool–stannous chloride mordant for natural dye extracted from dragon fruit.</p>
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<p>TGA curves of undyed and dyed wool fabric with dragon fruit extract.</p>
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<p>Dye absorption spectrum of dragon fruit dye in the range of 400 nm to 700 nm.</p>
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<p>Chromatogram of dragon fruit dye.</p>
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<p>Mass spectra of degraded compounds.</p>
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<p>Antibacterial activity of undyed and dyed wool fabrics with and without mordant against <span class="html-italic">E. coli</span> and <span class="html-italic">S. aureus</span>.</p>
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14 pages, 3150 KiB  
Article
Comparative Study of TPGS and Soluplus Polymeric Micelles Embedded in Poloxamer 407 In Situ Gels for Intranasal Administration
by Bence Sipos, Frézia Földes, Mária Budai-Szűcs, Gábor Katona and Ildikó Csóka
Gels 2024, 10(8), 521; https://doi.org/10.3390/gels10080521 - 9 Aug 2024
Viewed by 229
Abstract
This study aims to highlight the importance of choosing the appropriate co-polymer or co-polymer mixed combinations in order to design value-added nasal dosage forms. Local therapy of upper respiratory tract-related infections, such as nasal rhinosinusitis is of paramount importance, thus advanced local therapeutic [...] Read more.
This study aims to highlight the importance of choosing the appropriate co-polymer or co-polymer mixed combinations in order to design value-added nasal dosage forms. Local therapy of upper respiratory tract-related infections, such as nasal rhinosinusitis is of paramount importance, thus advanced local therapeutic options are required. Dexamethasone was encapsulated into three different polymeric micelle formulations: Soluplus or TPGS-only and their mixed combinations. Dynamic light scattering measurements proved that the particles have a micelle size less than 100 nm in monodisperse distribution, with high encapsulation efficiency above 80% and an at least 7-fold water solubility increase. Tobramycin, as an antimicrobial agent, was co-formulated into the in situ gelling systems which were optimized based on gelation time and gelation temperature. The sol–gel transition takes place between 32–35 °C, which is optimally below the temperature of the nasal cavity in a quick manner below 5 min, a suitable strategic criterion against the mucociliary clearance. In vitro drug release and permeability studies confirmed a rapid kinetics in the case of the encapsulated dexamethasone accompanied with a sustained release of tobramycin, as the hydrophilic drug. Full article
(This article belongs to the Section Gel Analysis and Characterization)
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<p>Phase solubility study of DXM in the presence of varying concentrations of Soluplus (red) and TPGS (blue) measured at 25 °C. Results are average ± SD (<span class="html-italic">n</span> = 3).</p>
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<p>Gelation temperature measured via rotational viscosimetry at various Poloxamer 407 concentrations. DT_SP formulation: red, DT_TPGS formulation: blue, DT_SP/TPGS formulation: green. Results are average ± SD (<span class="html-italic">n</span> = 3).</p>
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<p>Gelation time measured via rotational viscosimetry at various Poloxamer 407 concentrations. DT_SP formulation: red, DT_TPGS formulation: blue, DT_SP/TPGS formulation: green. Results are average ± SD (<span class="html-italic">n</span> = 3).</p>
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<p>In vitro mucoadhesion study—mucoadhesive force (blue) and mucoadhesive work (red) regarding the different in situ gelling formulations showing a moderately high mucoadhesive tendency. Results are average ± SD (<span class="html-italic">n</span> = 5).</p>
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<p>In vitro drug release profile of dexamethasone (<b>A</b>) and tobramycin (<b>B</b>) from the formulations and their references showing enhanced drug release in the case of the dexamethasone-loaded polymeric micelles. Results are average ± SD (<span class="html-italic">n</span> = 3).</p>
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<p>In vitro nasal passive diffusion study of dexamethasone (<b>A</b>) and tobramycin (<b>B</b>) from the formulations and their references. Results show the enhanced permeation profile of the dexamethasone-loaded polymeric micelles and in the case of tobramycin. Results are average ± SD (<span class="html-italic">n</span> = 3).</p>
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26 pages, 3224 KiB  
Review
Plant-Derived Antimicrobials and Their Crucial Role in Combating Antimicrobial Resistance
by Paola Angelini
Antibiotics 2024, 13(8), 746; https://doi.org/10.3390/antibiotics13080746 - 9 Aug 2024
Viewed by 535
Abstract
Antibiotic resistance emerged shortly after the discovery of the first antibiotic and has remained a critical public health issue ever since. Managing antibiotic resistance in clinical settings continues to be challenging, particularly with the rise of superbugs, or bacteria resistant to multiple antibiotics, [...] Read more.
Antibiotic resistance emerged shortly after the discovery of the first antibiotic and has remained a critical public health issue ever since. Managing antibiotic resistance in clinical settings continues to be challenging, particularly with the rise of superbugs, or bacteria resistant to multiple antibiotics, known as multidrug-resistant (MDR) bacteria. This rapid development of resistance has compelled researchers to continuously seek new antimicrobial agents to curb resistance, despite a shrinking pipeline of new drugs. Recently, the focus of antimicrobial discovery has shifted to plants, fungi, lichens, endophytes, and various marine sources, such as seaweeds, corals, and other microorganisms, due to their promising properties. For this review, an extensive search was conducted across multiple scientific databases, including PubMed, Elsevier, ResearchGate, Scopus, and Google Scholar, encompassing publications from 1929 to 2024. This review provides a concise overview of the mechanisms employed by bacteria to develop antibiotic resistance, followed by an in-depth exploration of plant secondary metabolites as a potential solution to MDR pathogens. In recent years, the interest in plant-based medicines has surged, driven by their advantageous properties. However, additional research is essential to fully understand the mechanisms of action and verify the safety of antimicrobial phytochemicals. Future prospects for enhancing the use of plant secondary metabolites in combating antibiotic-resistant pathogens will also be discussed. Full article
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<p>Broth microdilution for antibacterial testing as recommended by the Clinical and Laboratory Standards Institute (CLSI) M07-A9: Methods for Dilution Antimicrobial Susceptibility Tests for Bacteria That Grow Aerobically; Approved Standard—Ninth Edition [<a href="#B55-antibiotics-13-00746" class="html-bibr">55</a>].</p>
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18 pages, 1972 KiB  
Review
Contemporary Speculations and Insightful Thoughts on Buckwheat—A Functional Pseudocereal as a Smart Biologically Active Supplement
by Vladimir S. Kurćubić, Slaviša B. Stajić, Vladimir Jakovljević, Vladimir Živković, Nikola Stanišić, Pavle Z. Mašković, Vesna Matejić and Luka V. Kurćubić
Foods 2024, 13(16), 2491; https://doi.org/10.3390/foods13162491 - 8 Aug 2024
Viewed by 415
Abstract
Today, food scientists are interested in more rational use of crops that possess desirable nutritional properties, and buckwheat is one of the functional pseudocereals that represents a rich source of bioactive compounds (BACs) and nutrients, phytochemicals, antimicrobial (AM) agents and antioxidants (AOs), which [...] Read more.
Today, food scientists are interested in more rational use of crops that possess desirable nutritional properties, and buckwheat is one of the functional pseudocereals that represents a rich source of bioactive compounds (BACs) and nutrients, phytochemicals, antimicrobial (AM) agents and antioxidants (AOs), which can be effectively applied in the prevention of malnutrition and celiac disease and treatment of various important health problems. There is ample evidence of the high potential of buckwheat consumption in various forms (food, dietary supplements, home remedies or alone, or in synergy with pharmaceutical drugs) with concrete benefits for human health. Contamination as well as other side-effects of all the aforementioned forms for application in different ways in humans must be seriously considered. This review paper presents an overview of the most important recent research related to buckwheat bioactive compounds (BACs), highlighting their various functions and proven positive effects on human health. Full article
(This article belongs to the Section Nutraceuticals, Functional Foods, and Novel Foods)
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<p>Experimental fields with <span class="html-italic">Fagopyrum esculentum</span> (Kopaonik Mountain, Serbia), maturity stage.</p>
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<p>Experimental fields with <span class="html-italic">Fagopyrum esculentum</span> (Ponikve, Tara Mountain, Serbia), flowering phase.</p>
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21 pages, 3340 KiB  
Article
Development of Xanthoangelol-Derived Compounds with Membrane-Disrupting Effects against Gram-Positive Bacteria
by Siyu Yang, Fangquan Liu, Yue Leng, Meiyue Zhang, Lei Zhang, Xuekun Wang and Yinhu Wang
Antibiotics 2024, 13(8), 744; https://doi.org/10.3390/antibiotics13080744 - 7 Aug 2024
Viewed by 398
Abstract
Infections caused by multidrug-resistant pathogens have emerged as a serious threat to public health. To develop new antibacterial agents to combat such drug-resistant bacteria, a class of novel amphiphilic xanthoangelol-derived compounds were designed and synthesized by mimicking the structure and function of antimicrobial [...] Read more.
Infections caused by multidrug-resistant pathogens have emerged as a serious threat to public health. To develop new antibacterial agents to combat such drug-resistant bacteria, a class of novel amphiphilic xanthoangelol-derived compounds were designed and synthesized by mimicking the structure and function of antimicrobial peptides (AMPs). Among them, compound 9h displayed excellent antimicrobial activity against the Gram-positive strains tested (MICs = 0.5–2 μg/mL), comparable to vancomycin, and with low hemolytic toxicity and good membrane selectivity. Additionally, compound 9h demonstrated rapid bactericidal effects, low resistance frequency, low cytotoxicity, and good plasma stability. Mechanistic studies further revealed that compound 9h had good membrane-targeting ability and was able to destroy the integrity of bacterial cell membranes, causing an increase in intracellular ROS and the leakage of DNA and proteins, thus accelerating bacterial death. These results make 9h a promising antimicrobial candidate to combat bacterial infection. Full article
(This article belongs to the Topic Antimicrobial Agents and Nanomaterials)
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<p>Structure of CAS-13, XF-73, and PMX-30063.</p>
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<p>Design concept for amphiphilic xanthoangelol-derived compounds by mimicking the structure and the biological function of AMPs.</p>
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<p>Plasma stability and cytotoxicity of compound <b>9h.</b> Plasma stability (<b>A</b>) and bactericidal activity in complex mammalian fluids (<b>B</b>), and in vitro cytotoxicity (<b>C</b>) of <b>9h</b> toward LO2 cells. Data are expressed as mean ± standard deviation (n = 3).</p>
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<p>Time-kill kinetics (<b>A</b>) and bacterial resistance study (<b>B</b>) of <b>9h</b> against <span class="html-italic">S. aureus</span> ATCC43300. Data are expressed as mean ± standard deviation (n = 3).</p>
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<p>Antibiofilm activity of <b>9h</b>. (<b>A</b>) Inhibition of <span class="html-italic">S. aureus</span> biofilm formation by <b>9h</b>. (<b>B</b>) Eradication of the preformed <span class="html-italic">S. aureus</span> biofilm by <b>9h</b>. Error bars represent standard deviation from the mean of triplicate readout. * <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, *** <span class="html-italic">p</span> &lt; 0.001, and **** <span class="html-italic">p</span> &lt; 0.0001, compared with the control group.</p>
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<p>Fluorescence and electron scanning microscopy. (<b>A</b>) SEM images of the cell membrane of <span class="html-italic">S. aureus</span> cells, scar bar: 1.00 um. (<b>B</b>) Fluorescence micrographs of <span class="html-italic">S. aureus</span> cells stained with DAPI and PI and treated with <b>9h,</b> scar bar: 50 um.</p>
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<p>Antibacterial mechanism of compound <b>9h</b>. (<b>A</b>) Cytoplasmic membrane depolarization against <span class="html-italic">S. aureus</span> by compound <b>9h</b>. (<b>B</b>) Cell membrane permeabilization against <span class="html-italic">S. aureus</span> by compound <b>9h</b>. Data are expressed as mean ± standard deviation (n = 3).</p>
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<p>Antibacterial mechanism of compound <b>9h</b> against <span class="html-italic">S. aureus</span> ATCC43300. (<b>A</b>) Intracellular ROS changes after the treatment of <b>9h</b>. (<b>B</b>) DNA leakage caused by compound <b>9h</b>. (<b>C</b>) Protein leakage caused by compound <b>9h</b>. Data are expressed as mean ± standard deviation (n = 3). ns, not significant. * <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, *** <span class="html-italic">p</span> &lt; 0.001, and **** <span class="html-italic">p</span> &lt; 0.0001, compared with the control group.</p>
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<p>Reagents and conditions: (a) pyridine, 150 °C, 10 h; (b) K<sub>2</sub>CO<sub>3</sub>, 1,3-dibromopropane, CH<sub>3</sub>CN, 60 °C, 8 h; (c) RH, K<sub>2</sub>CO<sub>3,</sub> CH<sub>3</sub>CN, 60 °C, 8 h.</p>
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<p>Reagents and conditions: (a) pyridine, 150 °C, 18 h; (b) K<sub>2</sub>CO<sub>3</sub>, CH<sub>3</sub>CN, 60 °C, 10 h; (c) RH, K<sub>2</sub>CO<sub>3,</sub> CH<sub>3</sub>CN, rt, 8 h.</p>
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11 pages, 1656 KiB  
Article
Immunomodulatory Effects and Protection in Sepsis by the Antibiotic Moxifloxacin
by Tiago R. Velho, Helena Raquel, Nuno Figueiredo, Ana Neves-Costa, Dora Pedroso, Isa Santos, Katharina Willmann and Luís F. Moita
Antibiotics 2024, 13(8), 742; https://doi.org/10.3390/antibiotics13080742 - 7 Aug 2024
Viewed by 341
Abstract
Sepsis is a leading cause of death in Intensive Care Units. Despite its prevalence, sepsis remains insufficiently understood, with no substantial qualitative improvements in its treatment in the past decades. Immunomodulatory agents may hold promise, given the significance of TNF-α and IL-1β as [...] Read more.
Sepsis is a leading cause of death in Intensive Care Units. Despite its prevalence, sepsis remains insufficiently understood, with no substantial qualitative improvements in its treatment in the past decades. Immunomodulatory agents may hold promise, given the significance of TNF-α and IL-1β as sepsis mediators. This study examines the immunomodulatory effects of moxifloxacin, a fluoroquinolone utilized in clinical practice. THP1 cells were treated in vitro with either PBS or moxifloxacin and subsequently challenged with lipopolysaccharide (LPS) or E. coli. C57BL/6 mice received intraperitoneal injections of LPS or underwent cecal ligation and puncture (CLP), followed by treatment with PBS, moxifloxacin, meropenem or epirubicin. Atm−/− mice underwent CLP and were treated with either PBS or moxifloxacin. Cytokine and organ lesion markers were quantified via ELISA, colony-forming units were assessed from mouse blood samples, and DNA damage was evaluated using a comet assay. Moxifloxacin inhibits the secretion of TNF-α and IL-1β in THP1 cells stimulated with LPS or E. coli. Intraperitoneal administration of moxifloxacin significantly increased the survival rate of mice with severe sepsis by 80% (p < 0.001), significantly reducing the plasma levels of cytokines and organ lesion markers. Notably, moxifloxacin exhibited no DNA damage in the comet assay, and Atm−/− mice were similarly protected following CLP, boasting an overall survival rate of 60% compared to their PBS-treated counterparts (p = 0.003). Moxifloxacin is an immunomodulatory agent, reducing TNF-α and IL-1β levels in immune cells stimulated with LPS and E. coli. Furthermore, moxifloxacin is also protective in an animal model of sepsis, leading to a significant reduction in cytokines and organ lesion markers. These effects appear unrelated to its antimicrobial activity or induction of DNA damage. Full article
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<p>Moxifloxacin inhibits the secretion of IL-1β and TNF-α. THP-1 cells were incubated with <span class="html-italic">Escherichia coli</span> (<b>A</b>,<b>B</b>) or lipopolysaccharide (LPS) (<b>C</b>,<b>D</b>), with moxifloxacin at concentrations of 5, 10 and 20 μM. IL-1β and TNF-α were reduced with both the stimuli. ns: non-significant; *: <span class="html-italic">p</span> &lt; 0.05; **: <span class="html-italic">p</span> &lt; 0.01.</p>
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<p>Moxifloxacin protection against sepsis. (<b>A</b>) Survival of C57BL/6 WT mice subjected to CLP treated with carrier (PBS), epirubicin (0.6 μg/g body weight) or moxifloxacin (20 μg/g body weight), at time of procedure and 24 h later. (<b>B</b>) Survival of C57BL/6 WT with LPS treated with PBS or moxifloxacin (20 μg/g body weight). (<b>C</b>) Survival of ATM-KO mice subjected to CLP treated with carrier (PBS) or moxifloxacin (20 μg/g body weight) at time of procedure and 24 h later. ns: non-significant; *: <span class="html-italic">p</span> &lt; 0.05; **: <span class="html-italic">p</span> &lt; 0.01; ***: <span class="html-italic">p</span> &lt; 0.001; ****: <span class="html-italic">p</span> &lt; 0.0001.</p>
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<p>Moxifloxacin has anti-inflammatory and protective effects in vivo. Moxifloxacin reduces inflammation and tissue lesions associated with CLP, as assessed by the reduced plasma levels of TNFα (<b>A</b>), IL1β (<b>B</b>), IL6 (<b>C</b>), and LDH (<b>E</b>), ALT (<b>F</b>) and urea (<b>G</b>) in C57BL/6 WT animals 24 h after CLP followed by treatment with PBS (C + P), epirubicin (C + E), moxifloxacin (C + MX) or meropenem (C + MP). Lactate levels were not changed between all groups (<b>H</b>). Polymicrobial load (CFU) in blood (<b>D</b>) of C57BL/6 WT animals 24 h after CLP followed by treatment with PBS (C + P), moxifloxacin (C + MX) or meropenem (C + MP). ns: non-significant; *: <span class="html-italic">p</span> &lt; 0.05; **: <span class="html-italic">p</span> &lt; 0.01; ***: <span class="html-italic">p</span> &lt; 0.001.</p>
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<p>DNA damage in THP-1 cells treated with moxifloxacin and etoposide. Comet assay performed on THP-1 cells verified that DNA damage is similar in all groups incubated with PBS (<b>A</b>), <span class="html-italic">E. coli</span> (<b>B</b>), and with moxifloxacin (4 h), at 5 (<b>C</b>), 10 (<b>D</b>) and 20 (<b>E</b>) μM following stimulation with <span class="html-italic">E. coli</span>. On the other hand, treatment with etoposide (<b>F</b>) resulted in increased average of DNA in tail, representing high DNA damage.</p>
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13 pages, 2488 KiB  
Article
Virulence and Antimicrobial Resistance Characterization of Glaesserella parasuis Isolates Recovered from Spanish Swine Farms
by Alba González-Fernández, Oscar Mencía-Ares, María José García-Iglesias, Máximo Petrocchi-Rilo, Rubén Miguélez-Pérez, César Bernardo Gutiérrez-Martín and Sonia Martínez-Martínez
Antibiotics 2024, 13(8), 741; https://doi.org/10.3390/antibiotics13080741 - 6 Aug 2024
Viewed by 342
Abstract
Glaesserella (Haemophilus) parasuis, the causative agent of Glässer’s disease, is present in most pig farms as an early colonizer of the upper respiratory tract. It exhibits remarkable variability in virulence and antimicrobial resistance (AMR), with virulent strains capable of inducing [...] Read more.
Glaesserella (Haemophilus) parasuis, the causative agent of Glässer’s disease, is present in most pig farms as an early colonizer of the upper respiratory tract. It exhibits remarkable variability in virulence and antimicrobial resistance (AMR), with virulent strains capable of inducing respiratory or systemic disease. This study aimed to characterize the virulence and the AMR profiles in 65 G. parasuis isolates recovered from Spanish swine farms. Virulence was assessed using multiplex leader sequence (LS)-PCR targeting vtaA genes, with all isolates identified as clinical (presumed virulent). Pathotyping based on ten pangenome genes revealed the virulent HPS_22970 as the most frequent (83.1%). Diverse pathotype profiles were observed, with 29 unique gene combinations and two isolates carrying only potentially non-virulent pangenome genes. AMR phenotyping showed widespread resistance, with 63.3% classified as multidrug resistant, and high resistance to clindamycin (98.3%) and tylosin (93.3%). A very strong association was found between certain pathotype genes and AMR phenotypes, notably between the virulent HPS_22970 and tetracycline resistance (p < 0.001; Φ = 0.58). This study reveals the wide diversity and complexity of G. parasuis pathogenicity and AMR phenotype, emphasizing the need for the targeted characterization of clinical isolates to ensure appropriate antimicrobial treatments and the implementation of prophylactic measures against virulent strains. Full article
(This article belongs to the Special Issue Antimicrobial Resistance and Virulence in Veterinary Pathogens)
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Figure 1
<p>Pathotype characterization of 65 <span class="html-italic">G. parasuis</span> isolates from Spanish swine farms: (<b>a</b>) pathotype clustering based on the presence of ten pangenome genes, using the unweighted pair group method with arithmetic mean (UPGMA) as the hierarchical clustering method; (<b>b</b>) frequency (%) of each pathotype gene; and (<b>c</b>) principal component analysis (PCA) of the ten evaluated pangenome genes, showing grouping based on pathologic process and TbpB cluster of each <span class="html-italic">G. parasuis</span> isolate.</p>
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<p>Antimicrobial resistance (AMR) characterization at the class level of 60 <span class="html-italic">G. parasuis</span> isolates from Spanish swine farms: (<b>a</b>) AMR phenotype clustering based on antimicrobial classes, using the unweighted pair group method with arithmetic mean (UPGMA) as the hierarchical clustering method, and (<b>b</b>) principal component analysis (PCA) of the AMR patterns, showing grouping based on the TbpB cluster of each <span class="html-italic">G. parasuis</span> isolate.</p>
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<p>Network associations between pathotype genes and antimicrobial resistance (AMR) at the class level in 60 <span class="html-italic">G. parasuis</span> isolates from Spanish swine farms. Node size is determined by the percentage occurrence of the pathotype gene or AMR class. Edge size is proportional to the magnitude of the association based on the Φ coefficient. The network was constructed using significant associations (<span class="html-italic">p</span> &lt; 0.05).</p>
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