Search Results (287)

Objectives: Cefideroccol (FDC) is a siderophore cephalosporin with potent antibacterial activity against a wide range of Gram-negative multidrug-resistant (MDR) microorganisms. We investigated the anti-biofilm capacity of FDC against clinical strains. Methods: This multicenter study was conducted on 28 selected strains of MDR Gram-negative bacilli isolated from clinical samples of Pseudomonas aeruginosa (n = 5), Acinetobacter baumannii (n = 11), and Klebsiella pneumoniae (n = 12). We first determined the minimum inhibitory concentration (MIC) of each strain using the microdilution method. We also defined the minimum biofilm inhibitory concentration (MBIC) as a ≥50% reduction in tetrazolium salt (XTT) (as recommended in the 2017 Spanish Microbiology Protocols [SEIMC] for the microbiological diagnosis of infections related to the formation of biofilms). We also analyzed the reduction in the following biofilm variables after an 8 mg/mL FDC treatment: the CFU count, the cell viability, the biomass, the metabolic activity, and extracellular α or β polysaccharides. Results: The MIC₅₀ and MBIC₅₀ of FDC were 0.5 mg/L and 64 mg/L, respectively. We observed a mean (SD) fold increase in the susceptibility to FDC between planktonic and sessile cells for P. aeruginosa, A. baumannii, and K. pneumoniae of 9.60 (0.55), 6.27 (2.28), and 6.25 (2.80), respectively. When 8 mg/mL of FDC was tested, we observed that the best median (IQR) percentage reductions were obtained for cell viability and the extracellular matrix (73.1 [12.4–86.5] and 79.5 [37.3–95.5], respectively), particularly for P. aeruginosa. The lowest percentage reduction rates were those obtained for biomass. Conclusions: We demonstrated that the susceptibility to FDC was significantly reduced when strains were in a biofilm state. The best percentage reduction rates for all biofilm-defining variables were observed for P. aeruginosa. Our results need to be validated using a larger collection of clinical samples. Full article

Poplar leaves (Populi folium) are a herbal remedy traditionally used for the treatment of rheumatic diseases and prostate inflammation. The aim of our study was a comprehensive identification of secondary metabolites occurring in the leaves of Populus alba, Populus × candicans, and Populus nigra, in order to search for a source of raw plant material rich in active compounds. Total salicylate (TSC), flavonoid (TFC), and phenolic compound (TPC) contents were determined, and the antioxidant potential was assessed using DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS (2,2′-azino-bis(3-ethylbenzothiazoline- 6-sulfonic acid) diammonium salt), and FRAP (ferric reducing antioxidant power) assays as well as 2D-TLC (two-dimensional thin layer chromatography) bioautography using DPPH, riboflavin-light-NBT (nitro blue tetrazolium chloride), and xanthine oxidase inhibition tests. Secondary metabolites present in the analyzed poplar leaves were identified under the developed HPLC-DAD-ESI/MS (high performance liquid chromatography with photodiode array detection and electrospray ionization mass spectrometric detection analysis conditions and using the 2D-TLC method. Among the 80 identified compounds, 13 were shown for the first time in the genus Populus. The most diverse and similar set of flavonoids characterized the leaves of P. × candicans and P. nigra, while numerous salicylic compounds were present in the leaves of P. alba and P. × candicans. All analyzed leaves are a rich source of phenolic compounds. The highest flavonoid content was found in the leaves of P. × candicans and P. nigra, while the leaves of P. alba were characterized by the highest content of salicylates. All examined poplar leaves demonstrated antioxidant potential in all the assays used, which decreased in the following order: P. nigra, P. × candicans, P. alba. Full article

Background: Colon cancer is one of the leading causes of cancer-related deaths today. Crucial research continues for the ideal chemotherapy. In this context, natural compounds of plant origin play an important role in the development of new anticancer drugs. Methods: In this study, the effects of Consolida orientalis ethanol extract (flower parts), Smyrnium rotundifolium ethanol extract (aerial parts), and Euphorbia virgata ethanol extract (aerial parts) samples on HT-29 (human colorectal adenocarcinoma cell line) and healthy CCD-18Co (human normal colon fibroblast cell line) were investigated for the first time in the literature by applying 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) test within the scope of in vitro cytotoxicity analysis. Results: As a result of the study, it was observed that all plant extracts were most effective at 72 h. S. rotundifolium ethanol extract (aerial parts) was found to be the most effective on the HT-29 cell line. Both the higher cell viability of C. orientalis in healthy cells applied to it compared to S. rotundifolium and its effectiveness on colon cancer cell lines make C. orientalis more advantageous. Conclusions: When evaluating the efficacy of extracts on cancer cells, the load on healthy cells should be taken into account. Therefore, C. orientalis ethanol extract (flower parts) was found to have the potential to be a chemotherapeutic agent against colon cancer. Chemical reactivities of the dominant components of bioactive components were analyzed via Conceptual Density Functional Theory-based calculations. The power of the interactions with EGFR kinase of these compounds is checked via Molecular Docking Calculations. It was noted that Chlorogenic acid, which is the most reactive bioactive component, has a stronger binding to the mentioned enzyme. Full article

Levelers are indispensable additives for achieving void-free, bottom-up superconformal copper filling of microvias. Establishing the molecular-level correlation between leveler structure and performance is therefore essential to the continued advancement of microelectronic copper-plating technology. Herein, nitro blue tetrazolium chloride (NBT) is identified as an efficient leveler for copper microvia superfilling. A multiscale strategy—combining electrochemical measurements, X-ray photoelectron spectroscopy (XPS), density functional theory (DFT) calculations, and molecular dynamics (MD) simulations—is employed to elucidate the action mechanism of NBT and pinpoint its electroactive sites. Electrochemical tests show that NBT markedly suppresses copper deposition and, together with polyethylene glycol (PEG), effectively resists competitive adsorption by bis-(3-sulfopropyl) disulfide (SPS), thereby enhancing the microvia superfilling performance of the PEG–SPS–NBT additive system. DFT results reveal that the nitro groups and tetrazolium rings constitute the primary adsorption centers on the copper surface; the nitro groups additionally strengthen intermolecular interactions between NBT and PEG. MD simulations further confirm that NBT anchors onto the Cu(111) surface predominantly through these NO₂ groups and the tetrazolium ring, while co-adsorbed PEG enhances the overall adsorption strength of NBT. The electroplating experiment demonstrates that NBT can act as an effective leveler for microvia superfilling. Moreover, XPS analyses further confirm the synergistic co-adsorption of NBT and PEG and verify that the NO₂ groups and tetrazolium rings are the dominant adsorption sites of NBT. Collectively, the electroplating, XPS, electrochemical, DFT, and MD findings clarify the structure–activity relationship of NBT and provide rational guidelines for designing next-generation copper-plating levelers. Full article

Precision agriculture facilitates improved management by studying the spatial and temporal variability of soil attributes. Soybean (Glycine max (L.) Merrill) seeds may exhibit distinct quality when produced in different management zones. This study aimed to validate management zones during seed production and identify the variability and spatial distribution of soybean seed physiological quality using geostatistical tools. Management zones were defined based on interpolated maps of soil and vegetation attributes using the Smart Map Plugin (SMP) within the QGIS environment. Post-harvest, the variability of physiological seed quality across different management zones was assessed. Germination, accelerated aging, dry weight, emergence, electrical conductivity, and tetrazolium tests were conducted in a completely randomized design. Soil attributes, initial plant stand, and soybean seed productivity validated the management zones. Physiological seed quality varies across the production field, particularly in terms of vigor, thereby enhancing diagnostics through map interpolation. Geostatistics enable determination of the spatial distribution of soybean seed physiological quality in seed production areas, facilitating decision-making regarding harvest zones. Full article

The enzymes in honey can originate not only from bees and the plants from which the bees collect pollen and nectar but also from feed provided by beekeepers. Enzymes that hydrolyze sucrose—present in honey (α-glucosidase) or honey adulterated with invert syrup (β-fructofuranosidase)—can be distinguished using zymography, where enzymatic bands are detected with nitroblue tetrazolium (NBT) after sugar removal via ultrafiltration. This method enables the identification of honey produced in hives that have been improperly fed with invert syrup, leading to the mixture of natural honey and syrup, and offers a practical tool to detect indirect adulteration. The NBT assay, in combination with ultrafiltration, was used to determine the isoelectric point of honey bee α-glucosidases. The pI value of 6.63 for isoforms found in the head, midgut, and natural honey extracts during winter can be attributed to α-glucosidase III. Two additional isoforms with isoelectric points of 5.20 and 5.77 were observed in the midgut extract and may correspond to α-glucosidase I and II. The difference between α-glucosidase and β-fructofuranosidase was confirmed using a substrate specificity test, followed by thin-layer chromatography, where it was confirmed that α-glucosidase from natural honey, bee head, and bee midgut does not hydrolyze raffinose, in contrast to yeast β-fructofuranosidase. Full article

This study investigated the anti-SARS-CoV-2 activity of Polysaccharides (PSs) from three species of marine bacteria (Alteromonas nigrifaciens KMM 156, Cobetia amphilecti KMM 3890, and Idiomarina abyssalis KMM 227^T). The chemical structure of PSs from marine bacteria is characterized using ¹H and ¹³C NMR spectroscopy, including 2D NMR experiments. PS from A. nigrifaciens KMM 156 consists of tetrasaccharide repeating units containing two L-rhamnose residues and one residue each of 2-acetamido-2-deoxy-D-glucose and an ether of D-glucose with (R)-lactic acid, 3-O-[(R)-1-carboxyethyl]-D-glucose. PS from C. amphilecti KMM 3890 is constructed from branched trisaccharide repeating units consisting of D-glucose, D-mannose, and sulfated 3-deoxy-D-manno-oct-2-ulosonic acid. A unique PS from deep-sea marine bacterium I. abyssalis KMM 227^T consists of branched pentasaccharide repeating units and is characterized by the presence of a rare bacterial polysaccharide component 2-O-sulfate-3-N-(4-hydroxybutanoyl)-3,6-dideoxy-D-glucose. The activity of PSs against SARS-CoV-2 was assessed by inhibition of the virus cytopathogenic effect (CI) in the methylthiazolyl tetrazolium (MTT) test and using a real-time reverse transcription polymerase chain reaction (RT-PCR-RV). Results of the study demonstrate that PSs, which differ in chemical structure, exhibited anti-SARS-CoV-2 activity differences. This is confirmed both in the test of inhibition of the virus CI and in the reduction in the SARS-CoV-2 virus RNA level. PSs from A. nigrifaciens KMM 156 exhibited the strongest anti-SARS-CoV-2 effect, effectively inhibiting the stages of attachment and penetration of SARS-CoV-2 into the cells. Full article

Background: Rutin and quercetin are natural flavonoids with a variety of beneficial health effects, including anticancer activity. In the present study, we compared cytotoxicity and chemosensitization of human colon cancer HCT116 cells to anticancer drugs 5-fluorouracil (5-FU) and doxorubicin (DOX) by both compounds. Methods: The 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) test was used to determine cell viability. Western blot and immunofluorescence techniques were employed in the detection of expression of proteins involved in oxidative stress, apoptosis, and autophagy. Results: Quercetin treatment resulted in reduced cell viability compared to rutin at the same dose, suggesting greater cytotoxicity than rutin against HCT116 cells. Quercetin was also a better chemosensitizer of DOX than rutin, further reducing cell viability. However, rutin was a better chemosensitizer of 5-FU than quercetin. All treatments induced apoptosis, with rutin and DOX inducing intrinsic and 5-FU inducing extrinsic apoptotic cell death. Autophagy was induced in all treatments and played a pro-survival role, with the exception of DOX treatment. Different treatment regimens specifically modulated cancer cell signaling pathways involved in the regulation of oxidative stress, apoptosis, and autophagy. Conclusions: The results of the current study suggest that rutin and quercetin, although structural analogs, act as specific modulators of signaling pathways in cancer cells, differentially affecting cancer cell cytotoxicity and chemosensitization to anticancer drugs, based on the presence of a free hydroxyl group at the C-3 position of the flavonoid backbone at quercetin or rutinose in rutin. Full article

Background: Antibiotic-resistant Pseudomonas aeruginosa (P. aeruginosa) strains are an increasing cause of morbidity and mortality. Pulsed blue light (PBL) enhances porphyrin-induced reactive oxygen species and has been clinically shown to be harmless to the skin at low doses. Bacteriophages, viruses that infect bacteria, offer a promising non-antibiotic bactericidal approach. This study investigates the potential synergism between low-dose PBL and phage therapy against P. aeruginosa in planktonic cultures and preformed biofilms. Methods: We conducted a factorial dose–response in vitro study combining P. aeruginosa-specific phages with PBL (457 nm, 33 kHz) on both PA14 and multidrug-resistant PATZ2 strains. After excluding direct PBL effects on phage titer or activity, we assessed effectiveness on planktonic cultures using growth curve analysis (via growth_curve_outcomes, a newly developed, Python-based tool available on GitHub) , CFU, and PFU. Biofilm efficacy was evaluated using CFU post-sonication, crystal violet staining, and live/dead staining with confocal microscopy. Finally, we assessed reactive oxygen species (ROS) as a potential mechanism using the nitro blue tetrazolium reduction assay. ANOVA or Kruskal–Wallis tests with post hoc Tukey or Conover–Iman tests were used for comparisons (n = 5 biological replicates and technical triplicates). Results: The bacterial growth lag phase was significantly extended for phage alone or PBL alone, with a synergistic effect of up to 144% (p < 0.001 for all), achieving a 9 log CFU/mL reduction at 24 h (p < 0.001). In preformed biofilms, synergistic combinations significantly reduced biofilm biomass and bacterial viability (% Live, median (IQR): Control 80%; Phage 40%; PBL 25%; PBL&Phage 15%, p < 0.001). Mechanistically, PBL triggered transient ROS in planktonic cultures, amplified by phage co-treatment, while a biphasic ROS pattern in biofilms reflected time-dependent synergy. Conclusions: Phage therapy combined with PBL demonstrates a synergistic bactericidal effect against P. aeruginosa in both planktonic cultures and biofilms. Given the strong safety profile of PBL and phages, this approach may lead to a novel, antibiotic-complementary, safe treatment modality for patients suffering from difficult-to-treat antibiotic-resistant infections and biofilm-associated infections. Full article

Background and Objectives: Dexamethasone has been widely researched for its ability to promote osteogenic differentiation in mesenchymal stem cells in basic research. This study focused on examining the effects of dexamethasone on both cell viability and osteogenic differentiation in three-dimensional stem cell spheroids. Materials and Methods: These spheroids were created using concave microwells and exposed to dexamethasone at concentrations ranging from 0 μM to 100 μM, including intermediate levels of 0.1 μM, 1 μM, and 10 μM. Microscopic analysis was used to qualitatively assess cellular viability, while a water-soluble tetrazolium salt-based assay provided quantitative viability data. Osteogenic differentiation was evaluated by measuring alkaline phosphatase activity and calcium deposition using Alizarin Red staining. Additionally, the expression levels of genes associated with osteogenesis were measured through quantitative polymerase chain reaction. Results: The spheroids successfully self-assembled within the first 24 h and maintained their structural integrity over a seven-day period. Analysis of cell viability showed no statistically significant differences across the various dexamethasone concentrations tested. Although there was an observed increase in alkaline phosphatase activity and calcium deposition following dexamethasone treatment, these differences were not statistically significant. RUNX2 gene expression was upregulated in the 1 μM, 10 μM, and 100 μM groups, while COL1A1 expression significantly increased at 0.1 μM and 1 μM. Conclusions: These results indicate that dexamethasone supports cell viability and enhances RUNX2 and COL1A1 expression in stem cell spheroids. Full article

Gold nanoparticles stabilized with polyamidoamine dendrimers are one of the potential candidates for use as a contrast agent in computed tomography and a drug delivery agent. This work demonstrates a rapid, two-step synthesis of such complexes, which are size-stable for up to 18 months. The first step of the synthesis involves a short sonication of gold (III) chloride hydrate with polyamidoamine dendrimers of the fourth generation, while the second step uses microwaves to reduce gold (III) chloride hydrate with sodium citrate. The developed synthesis method enables rapid production of spherical and monodisperse gold nanoparticles stabilized with polyamidoamine dendrimers. Physicochemical characterization of the gold nanoparticle-polyamidoamine dendrimers complexes was performed using ultraviolet-visible spectroscopy, dynamic light scattering technique, infrared spectroscopy, atomic force microscopy, and transmission electron microscopy. The toxicity of synthesized complexes on the breast cancer MCF-7 cell line has been studied using the tetrazolium salt reduction test. The produced gold nanoparticles revealed lower toxicity levels on the MCF-7 cell line after 18 months from synthesis compared with newly synthesized colloids. Synthesized gold nanoparticles stabilized with dendrimers and commercially available gold nanoparticles stabilized with sodium citrate show similar toxicity levels on breast cancer cells. Full article

Cyperus esculentus is an invasive sedge causing high losses in many crops. Prevention is key in minimizing further spread and damage. Propagules (tubers or seeds) may spread via cattle manure. This study examined the effect of ensiling, digestion, and storage in manure on the viability of C. esculentus propagules. Propagules were subjected to five durations (0–16 weeks) in silage maize, seven durations (0–48 h) of ruminal digestion, and five durations of storage (0–16 weeks) in manure (slurry or farmyard), or combinations of previous processes. Afterwards, the viabilities were determined by a germination and tetrazolium test. After 6 weeks in a maize silo, the viability of the propagules was reduced by at least 96%. Incubation for 36 h in the rumen, followed by post-ruminal digestion in vitro, reduced seed viability by 30%. However, for the tubers, no effect was observed. The viability of seeds and tubers was reduced by 90% after 11.5 and 13.7 weeks of incubation in slurry, respectively. Compared with seeds, tubers were less tolerant to 12–24 h of animal digestion, followed by 8 weeks of storage in slurry. Keeping a maize silo closed for at least 6 weeks and maintaining slurry storage for at least 16 weeks are excellent measures to eliminate C. esculentus. For farmers, these preventive measures are relatively easy and cheap to implement compared to the requirements of curative control methods. Full article

Background and Objectives: Despite the development of treatment methods and the emergence of alternative new approaches in recent years, the visual prognosis of retinoblastoma contains deficiencies and this situation increases the need for the development of new treatment approaches. The cytotoxic and apoptosis-inducing effects of the combination of boswellic acid (BA), which has been determined to have significant potential in preclinical and clinical studies of various diseases, and Cisplatin (Cis), a potent chemotherapy agent, were investigated on the human retinoblastoma cell line (Y79). Materials and Methods: The cytotoxic effect of BA and Cis on Y79 cells was determined by the water soluble tetrazolium-1 (WST-1) test, the apoptotic rate of the cells was determined by annexin V staining, and the gene expressions of Protein53 (p53), Caspase-3 and Nuclear factor kappa B (NF-κB), which play an important role in apoptosis, were determined by RT-qPCR analysis. Interleukin 1-beta (IL1-β), tumor necrosis factor-α (TNF-α) and interferon γ (IFN-γ) levels were analyzed in cell lysates obtained from the experimental groups. Results: The combination of BA and Cis selectively inhibited the growth of Y79 cells and modulated NF-κB signaling, potentially through post-translational regulatory mechanisms. Moreover, it induced apoptosis by increasing p53 and Caspase-3 expressions, confirming its pro-apoptotic effects. Additionally, the combination treatment was associated with a reduction in inflammatory cytokine levels (TNF-α, IL1-β), suggesting a potential regulatory effect on inflammation-related pathways rather than direct inhibition of NF-κB activation. Conclusions: These findings suggest that BA combined with Cis inhibits Y79 retinoblastoma cell growth by inducing apoptosis and modulating NF-κB signaling. While NF-κB mRNA levels increased, reduced inflammatory cytokines and enhanced apoptosis suggest potential post-translational regulation. Further studies are needed to confirm NF-κB protein-level effects and in vivo efficacy. Full article

Fucoidans from Laminaria hyperborea (LH) can be antioxidative, antiangiogenic, and anti-inflammatory. In this study, a very high-molecular weight (3700 kDa) fucoidan from LH, FucBB04, was tested regarding its bioactivity in age-related macular degeneration (AMD) models in vitro. Primary retinal pigment epithelium (RPE) from pig eyes, human uveal melanoma cell line OMM-1, and RPE cell line ARPE-19 were used. Substituents of the extract were determined with chemical analysis. Cell viability was tested with tetrazolium assay (MTT), oxidative stress was induced by H₂O₂ or erastin, respectively. Secreted vascular endothelial growth factor A (VEGF-A) was assessed with ELISA. Retinal pigment epithelium 65 kDa protein (RPE65) and protectin (CD59) protein expression were tested in Western blot. Cell barrier was assessed by measuring trans-epithelial electrical resistance (TEER), phagocytic ability by a fluorescence assay. Gene expression and secretion of interleukin 6 (IL-6) and interleukin 8 (IL-8) were tested in real-time PCR and ELISA. FucBB04 displayed no oxidative stress protective effects. Its effect on VEGF was inconsistent, with VEGF secretion reduced in primary RPE, but not in ARPE-19. On the other hand, Lipopolysaccharide (LPS) and polyinosinic/polycytidylic acid (PIC)-induced IL-6 or IL-8 secretion was reduced by FucBB04, while complement inhibiting protein CD59 was not affected. In addition, FucBB04 did not influence the gene expression of IL-6 or IL-8. Visual cycle protein RPE65 expression, phagocytic ability, and barrier function were reduced by FucBB04. Very high-molecular weight fucoidan from LH shows bioactivities against AMD-related pathological pathways, but adverse effects on RPE function may limit its suitability as a therapeutic compound. Smaller high-molecular weight fucoidans are recommended for further research. Full article

Given the ecological significance and potential for afforestation and carbon sequestration of these species, this study contributes to optimizing nursery practices for successful regeneration and conservation efforts. Thus, this research assessed the physical and physiological seed quality and seedling production of Sequoia sempervirens, Sequoiadendron giganteum, and Pseudotsuga menziesii. For seed characteristics the following were tested: (I) Tetrazolium at concentrations: 0.0%, 0.1%, 0.5%, 1.0%; (II) moisture content and thousand-seed weight; (III) in-lab germination; and (IV) the classification of seeds’ viability through the use of a seed blower. Meanwhile, seedling production was tested: (I) five compositions of substrates and (II) doses of a controlled-release fertilizer (14-14-14): 0.0, 2.0, 4.0, 6.0, 8.0 g L⁻¹, for S. giganteum. The seed evaluations revealed no significant effect of tetrazolium concentrations on determining their viability. The water content results classify all species as orthodox. All species’ seeds were classified as small according to the weight of a thousand seeds. A maximum of 41% germination was observed for both S. sempervirens and S. giganteum, this value was 56% for P. menziesii, attributed to non-viability and emptiness. The seed blower increased germination by more than 20% for S. giganteum and almost 40% for P. menziesii. Seedling production was affected by the substrates, and a dosage of 4.0 g L⁻¹ of the controlled-release fertilizer is recommended for S. giganteum. Full article