Search Results (218)

Candida albicans is a major fungal pathogen associated with vulvovaginal candidiasis, and rapid, sensitive detection remains challenging, particularly in amplification-free formats. Here, we report NaPddCas, a microfluidic-free, droplet-based CRISPR/Cas12a detection strategy for qualitative identification of Candida albicans DNA. Unlike conventional bulk CRISPR assays, NaPddCas partitions the reaction mixture into vortex-generated polydisperse droplets, enabling spatial confinement of Cas12a activation events and effective suppression of background fluorescence. This compartmentalization substantially enhances detection sensitivity without nucleic acid amplification or microfluidic devices. Using plasmid and genomic DNA templates, NaPddCas achieved reliable detection at concentrations several orders of magnitude lower than bulk CRISPR/Cas12a reactions. The assay further demonstrated high specificity against non-target bacterial and fungal species and was successfully applied to clinical vaginal secretion samples. Importantly, NaPddCas is designed as a qualitative or semi-qualitative droplet-dependent digital detection method rather than a quantitative digital assay. Owing to its simplicity, sensitivity, and amplification-free workflow, NaPddCas represents a practical approach for laboratory-based screening of Candida albicans infections. Full article

The unicellular ciliate Paramecium caudatum undergoes a developmental transition from asexual binary fission to sexual reproduction during its mature stage. This transition is triggered by mating interactions between cells of complementary mating types, leading to aggregate formation, mating pairs, and the meiotic division of micronuclei. Although calcium-driven EF-hand kinases have been implicated as mating type proteins, the spatiotemporal dynamics of calcium signaling during conjugation have not been comprehensively characterized. In this study, we established a behavioral assay to isolate committed cells from aggregates immediately after mating onset, and developed an experimental system to monitor intracellular calcium fluctuations specifically expressed in these cells. By combining Ca²⁺/EGTA buffering and microinjection approaches, we manipulated extracellular and intracellular calcium levels and confirmed the continuous requirement of calcium ions for conjugation-specific functions. Two significant findings emerged. First, we identified, for the first time, a calcium atlas covering the entire cell, with ascending centers localized in the anterior, oral apparatus, and posterior regions. The calcium/Indo-1-AM fluorescence peaked at 6 h after mating initiation and declined gradually, but persisted until conjugation was completed at ~48 h. Second, we demonstrated that distinct intracellular calcium thresholds are required for each stage of mating, including maintenance of mating activity, commitment of micronuclei to meiosis, and two-stepwise formation of mating pairs. These thresholds function as regulatory checkpoints that coordinate subcellular localization and stage synchronization. Collectively, our findings highlight calcium ions as pivotal regulators of conjugation in Paramecium and propose a novel framework, the Paramecium calcium atlas, for understanding the cellular and molecular mechanisms underlying sexual reproduction in ciliates. Full article

Acetyl phosphate (AcP) is a microbial metabolite acting as a link between cell metabolism and signaling, providing the survival of bacteria in the host. AcP was also identified as an intermediate of pyruvate oxidation in mammalian mitochondria and was found in the human blood in some severe pathologies. The possible contribution of circulating AcP to the maintenance of the physiological or pathological states of the body has not been studied. Since AcP can function as a donor of phosphate groups, we have examined in vitro the influence of AcP on calcium signaling in mitochondria and cells by measuring the membrane potential and the calcium retention capacity of mitochondria by selective electrodes and by assaying the cell calcium signaling by Fura-2AM fluorescent radiometry. AcP was shown to induce a concentration-dependent increase in the mitochondrial resistance to calcium ion loading both in the control and in the presence of ADP. This effect was especially pronounced when mitochondria were incubated in a phosphate-free medium; under these conditions, AcP strongly raised the membrane potential and increased the rate of calcium uptake and the calcium retention capacity several times. Moreover, AcP induced similar changes in human cells when calcium signaling was activated by ATP, to a greater extent in neuroblastoma cells than in astrocytes. In the presence of AcP, a tendency for an increase in the amplitude and a decrease in the continuance of the ATP-induced calcium response was observed. These changes are probably associated with the activation of calcium buffering by mitochondria due to the delivery of phosphate during the hydrolysis of AcP. The results show that AcP is involved in the regulation of the Ca²⁺ balance in cells by activating the accumulation of calcium ions by mitochondria, especially under phosphate deficiency. A shift in calcium signaling mediated by AcP supplementation may be caused by hyperphosphatemia, which is now considered as one of basic contributors to cellular dysfunction and progression of various diseases, including sepsis. Full article

This research utilized the CRISPR/Cas9 editing method to generate six mutant strains of Escherichia coli (E. coli) DH5α targeting specific genes. The functional characterization and phenotypic analysis confirmed the regulatory roles of these genes in modifying membrane permeability. The variations in membrane permeability among the mutant strains were assessed by measuring electrical conductivity, ortho-nitrophenyl-β-D-galactopyranoside (ONPG) hydrolysis, and propidium iodide (PI) fluorescence, with E. coli DH5α:ompA′ exhibiting the most pronounced increase in membrane permeability. The function of these genes in transformation was analyzed from physicochemical and microscopic perspectives. Assays of plasmid transformation efficiency revealed a significant enhancement in the E. coli DH5α:ompA′ mutant strain, underscoring the critical function of outer membrane proteins in DNA acquisition. Permeability simulations were performed utilizing the E. coli DH5α:ompA′ mutant strain, grounded in a previously established model. The quantitative correlation between transformation efficiency and membrane permeability in this mutant conformed to the equation T = aP + c. Full article

Hepatitis B virus (HBV) persists in infected hepatocytes through covalently closed circular DNA (cccDNA), a stable episomal form that serves as the transcriptional template for viral replication. Accurate and sensitive quantification of intrahepatic cccDNA is crucial for evaluating antiviral therapies, particularly those targeting a functional cure. Here, we report the development of a novel, cccDNA-specific detection system combining recombinase polymerase amplification (RPA) with CRISPR/Cas12a-based fluorescence detection. We designed and validated CRISPR RNAs (crRNAs) targeting HBV cccDNA-specific regions conserved across genotypes A–D. Reaction conditions for both RPA and Cas12a detection were optimized to enhance sensitivity, specificity, and accuracy. The system reliably detected as few as 10 copies of cccDNA-containing plasmid per reaction and showed no cross-reactivity with non-cccDNA forms in serum or plasma, indicating assay specificity. When applied to liver tissue samples from 10 HBV-infected and 6 non-HBV patients, the RPA-CRISPR/Cas12a assay exhibited a high sensitivity (90%) and a strong correlation with qPCR results (R² = 0.9155), confirming its accuracy. In the conclusion, the RPA-CRISPR/Cas12a system provides a robust, cost-effective, and scalable platform for sensitive and specific quantification of intrahepatic HBV cccDNA. This method holds promises for research and high-throughput therapeutic screening applications targeting cccDNA clearance. Full article

Background/Objectives: Formation of tight contacts between oral soft tissue and dental implants is a significant challenge in contemporary implantology. An essential role in this process is played by oral epithelial cells. In the present study, we investigated how titanium and zirconia surfaces with different roughness influence various parameters of oral epithelial cells in vitro. Methods: We used the human oral squamous carcinoma Ca9-22 cell line and cultured them on the following surfaces: machined smooth titanium (TiM) and zirconia (ZrM) surfaces, as well as sandblasted and acid-etched titanium moderately rough (SLA) and zirconia (ZLA) surfaces. Cell proliferation/viability was measured by CCK-8 assay, and cell morphology was analyzed by fluorescent microscopy. The gene expression of interleukin (IL)-8, intercellular adhesion molecule (ICAM)-1, E-cadherin, integrin (ITG)-α6, and ITG-β4 was measured by qPCR, and the content of IL-8 in conditioned media by ELISA. Results: At the initial culture phase, cell proliferation was promoted by rougher surfaces. Differences in cell attachment were observed between machined and moderately rough surfaces. Machined surfaces were associated with slightly higher IL-8 levels (p < 0.05). Furthermore, both ZLA and SLA surfaces promoted the expression of (ITG)-α, ITG-β4, and ICAM-1 in Ca9-22 cells (p < 0.05). Surface material had no impact on the investigated parameters. Conclusions: Under the limitations of this in vitro study, some properties of oral epithelial cells, particularly the immunological and barrier function, are moderately modified by roughness but not by material. Hence, the roughness of the implant surface might play a role in the quality of the peri-implant epithelium. Full article

The urgent need for effective therapies against cancer and antimicrobial-resistant pathogens motivates the development of novel metal-based complexes. Herein, we report the synthesis and characterization of four novel cobalt(II) complexes with biologically relevant β-diketo ester ligands. The complexes were characterized via UV-Vis, FTIR, mass spectrometry, and elemental analysis. Their biological activities were evaluated through antimicrobial and cytotoxic assays. Complex B1 exhibited the strongest antimicrobial activity, with minimum inhibitory concentrations (MICs) of 0.23 mg/mL against Staphylococcus aureus and Proteus mirabilis, and 0.01 mg/mL against Mucor mucedo, exceeding the performance of ketoconazole. Cytotoxicity studies on SW480 colorectal cancer cells and HaCaT normal keratinocytes identified B3 as the most potent anticancer agent (IC₅₀ = 11.49 µM), selectively targeting tumor cells. Morphological analysis indicated apoptosis as the primary mode of cell death. Mechanistic studies were performed to elucidate interactions with biomolecules. UV-Vis and fluorescence spectroscopy, viscosity measurements, and molecular docking revealed that B3 binds strongly to calf thymus DNA via hydrophobic interactions and groove binding, and exhibits selective binding to bovine serum albumin (site II, subdomain IIIA). These results highlight the potential of cobalt(II) complexes as multifunctional agents with significant antimicrobial and antitumor activities and provide detailed insight into their molecular interactions with DNA and serum proteins. Full article

The widespread circulation of Eurasian avian-like H1N1 (EA H1N1) swine influenza virus poses significant zoonotic and pandemic risks worldwide. However, current diagnostic methods are difficult to deploy in the field, as they generally require specialized laboratory infrastructure and trained personnel. Here, we present a novel dual-signal detection platform that combines reverse transcription recombinase polymerase amplification (RT-RPA) with CRISPR/Cas12a technology for rapid, on-site EA H1N1 detection. We established an integrated one-tube assay by designing and optimizing RT-RPA primers targeting a conserved region of the hemagglutinin (HA) gene, together with engineered CRISPR/Cas12a guide RNAs exhibiting high specificity. The platform incorporates two complementary readout modes: real-time fluorescence monitoring and visual colorimetric detection using a smartphone. The assay shows excellent analytical specificity, with no cross-reactivity observed against other swine influenza virus subtypes or common swine pathogens, (including CSFV, PRRSV, PEDV, PCV, TGEV, and RV). The detection limit is 2 copies/μL, and the entire procedure can be completed within 30 mins using simple portable equipment. When evaluated on 86 clinical samples, the assay demonstrated 94.18% concordance with RT-qPCR. Compared with conventional diagnostic methods, this RT-RPA–CRISPR/Cas12a assay offers greater convenience and cost-effectiveness. Its strong potential for field-based rapid testing underscores promising application prospects in swine influenza surveillance and control programs. Full article

Paratuberculosis (PTB), caused by Mycobacterium avium subsp. paratuberculosis (MAP), is a chronic intestinal disease in ruminants. PTB is difficult to diagnose, control, and eradicate, leading to substantial economic losses. Thus, sensitive and specific detection methods are urgently required. crRNA and primers targeting the MAP ATPase FtsK gene were designed for recombinase polymerase amplification (RPA) and nested PCR. Fecal DNA was amplified using RPA or nested PCR, purified with Tris-saturated phenol-chloroform-isoamyl alcohol, and detected via CRISPR-Cas12a. Moreover, signals were read using a qPCR instrument, fluorescence reader, or lateral flow strips. RPA–CRISPR-Cas12a and nested PCR–CRISPR-Cas12a assays were optimized and validated on 50 clinical samples and 7 MAP cultures. The limits of detection were 1 × 10⁻¹⁰ μg/μL for RPA–CRISPR-Cas12a and 1 × 10⁻¹⁴ μg/μL for nested PCR–CRISPR-Cas12a. Efficient cleavage of the ssDNA reporter occurred at DNA concentrations of ≥1 × 10⁻⁴ μg/μL, producing a strong fluorescent signal. All three detection methods showed perfect agreement with reference assays across both sample sets. This study presents the first integration of RPA or nested PCR with CRISPR-Cas12a for MAP detection, enabling rapid, specific, and highly sensitive diagnosis. Flexible detection options allow adaptation to available resources and bacterial loads, supporting practical use in PTB control. Full article

Climate change in the Pannonian region is accelerating a shift toward autumn sowing of cool-season grain legumes (pea, faba bean, lentil, chickpea, lupine) to achieve higher yields, greater biomass production, enhanced nitrogen fixation, improved soil cover, and superior resource use efficiency compared with spring sowing. However, successful overwintering depends on the availability of robust winter-hardy cultivars. This review synthesizes recent breeding advances, integrating traditional approaches—such as germplasm screening, hybridization, and field-based selection—with genomics-assisted strategies, including genome-wide association studies (GWAS), quantitative trait locus (QTL) mapping, marker-assisted selection (MAS), and CRISPR/Cas-mediated editing of CBF transcription factors. Key physiological mechanisms—LT₅₀ determination, cold acclimation, osmoprotectant accumulation (sugars, proline), and membrane stability—are assessed using field survival rates, electrolyte leakage assays, and chlorophyll fluorescence measurements. Despite challenges posed by genotype × environment interactions, variable winter severity, and polygenic trait control, the release of cultivars worldwide (e.g., ‘NS-Mraz’, ‘Lavinia F’, ‘Ghab series’, ‘Pinklevi’, and ‘Rézi’) and ongoing breeding programs demonstrate substantial progress. Future breeding efforts will increasingly rely on genomic selection (GS), high-throughput phenomics, pangenomics, and G×E modeling to accelerate the development of climate-resilient legume cultivars, ensuring stable and sustainable production under increasingly unpredictable winter conditions. Full article

Streptomyces sp. MC1, a bacterium isolated from an environment contaminated with organic and inorganic pollutants, can reduce chromium and degrade lindane, making it a promising candidate for bioremediation. However, a major challenge in bioremediation trials is monitoring bacteria survival in soil. To assess the survival of Streptomyces sp. MC1 during bioremediation, we introduced fluorescence tagging and a selectable marker into this strain by intergeneric conjugation from Escherichia coli. Conjugation assays were performed using two E. coli strains (ET12567/pUZ8002 or S17-1) and Streptomyces sp. MC1 (spores or mycelium). The integrative plasmid pSC001, carrying a gene encoding the monomeric green fluorescent protein (mGFP), was used. Various donor and recipient concentrations were tested and the presence of MgCl₂ or CaCl₂ during conjugation was also evaluated. Optimal conditions included low concentrations of both Streptomyces sp. MC1 spores and E. coli S17-1, with MgCl₂ in the medium. Exconjugants were analyzed, confirming plasmid site-specific integration and mGFP expression. In bioremediation assays with soils co-contaminated with Cr(VI) and lindane, fluorescence-tagged Streptomyces sp. MC1 successfully demonstrated survival over 28 days. Our results, combined with the availability of the Streptomyces sp. MC1 genome sequence, will facilitate further characterization of this strain’s features and accelerate its development for bioremediation applications. Full article

Background: Bacterial keratitis, a major cause of corneal blindness, is frequently associated with biofilm-forming pathogens such as Klebsiella pneumoniae. Cyclic-di-GMP (c-di-GMP) controls biofilm development, which increases antibiotic resistance and makes treatment more difficult, highlighting the need for innovative therapeutic approaches. Methods: This study investigated cinnamaldehyde as a potential ocular therapeutic using combined computational and experimental approaches. Molecular docking and in vitro assays (XTT, resazurin reduction, crystal violet staining, qRT-PCR, and fluorescence microscopy) were used to evaluate the anti-biofilm and immunomodulatory activities of cinnamaldehyde (CA) against Klebsiella pneumoniae. Results: CA inhibited biofilm formation in a dose-dependent manner (≈89% at 1000 µM; >50% at 250 µM), reduced bacterial attachment to contact lenses, and downregulated key biofilm genes (mrkA, mrkC, ybtS, bolA). Docking analysis revealed strong binding affinity to the mrkH regulator (−5.46 kcal/mol. CA maintained more than 80% corneal cell viability by increasing IL-10, suppressing inflammatory mediators (IL-1β, IL-6, and TNF-α), and improving bacterial clearance. Conclusions: This study combines computational docking, biofilm quantification, immune cell assays, and functional gene expression analyses to reveal the ability of cinnamaldehyde not only to suppress biofilm formation but also to enhance macrophage-mediated clearance and modulate corneal immune responses, a multi-target approach not previously described in the context of bacterial keratitis. Such effects highlight its potential as a novel ocular drug candidate for protecting corneal integrity in infectious keratitis. Full article

Calcium phosphates are one of the main materials used in biomedicine for bone regeneration purposes. To improve the properties of biocompatible β-Ca₃(PO₄)₂, doping by bioactive, antibacterial is actively used, as well as luminescent ions. Co-doped phosphates Ca_8−xSr_xZnEu(PO₄)₇ with a β-Ca₃(PO₄)₂ (β-TCP)-type structure were synthesized through solid-state synthesis. The β-TCP-type structure was confirmed using X-ray powder diffraction and FTIR spectroscopy. Photoluminescence data, including excitation and emission spectra, decay curves, lifetime values and quantum yields, were collected for all samples. Ca_8−xSr_xZnEu(PO₄)₇ phosphates exhibit strong red-emission due to 4f-4f transitions of Eu³⁺ ions in disordered oxygen surrounding, with quantum yields reaching 54%. The phosphates demonstrated biocompatibility through MTT assay, with successful differentiation of aMSCs into the osteogenic lineage. Antibacterial activity was tested against four bacteria (E. coli, S. aureus, P. aeruginosa, and E. faecalis) and a fungus (C. albicans). It was found that the samples demonstrated antibacterial properties. The growth of E. coli and E. faecalis is significant inhibited by Ca_8−xSr_xZnEu(PO₄)₇ samples with 0 ≤ x ≤ 6.0. Analysis of mixed salt solubility using Eu³⁺ ions as a fluorescent probe showed that increasing Sr²⁺ concentration in Ca_8−xSr_xZnEu(PO₄)₇ delays both β-TCP phase resorption and HAP phase precipitation. These results demonstrate the potential of Ca_8−xSr_xZnEu(PO₄)₇ phosphates for bioimaging and bone healing control. Full article

Pleurotus nebrodensis, a rare endemic Sicilian mushroom with notable gastronomic and medicinal value, attracts interest for its potential antioxidant properties, though data on its biological effects in skin models are lacking. This study evaluated the antioxidant activities of several aqueous extracts from wild (1a, 2a, 3a, 1b, 2b, and 3b) and cultivated (CAN1 °F, 3A, 2B(II), and CAN2 °F) P. nebrodensis basidiomes in human keratinocytes (HaCaT cells). Extracts were characterized through DPPH radical scavenging assay, MTT viability assay, and intracellular ROS and mitochondrial SOX quantification by DCFH-DA and MitoSOX Red fluorescence analyses. The methodology specifically included two approaches in keratinocytes: co-treatment of extracts and H₂O₂ to investigate direct scavenger activity, and pre-treatment to assess the preventive activity on oxidative stress modulation. This analysis demonstrated that selected extracts (1b and CAN2 °F) exert a dual action, combining anti-intracellular ROS and anti-mitochondrial SOX preventive effect with a direct free radical scavenging activity in human keratinocytes. In particular, CAN2 °F exerts its activity predominantly through prevention (modulation of cellular defenses), while 1b primarily functions as a direct intracellular ROS and mitochondrial SOX scavenger. Notably, glucan quantification revealed a correlation between β-glucan content and the overall antioxidant activity. These findings provide the first evidence of P. nebrodensis’s anti-ROS and anti-SOX efficacy in human keratinocytes, highlighting its potential as a source of natural bioactives for cosmeceutical and dermatological applications. Full article

Golden pompano (Trachinotus ovatus) is the largest-scale marine aquaculture fish species in China, with a significant economic and nutritional value as a high-quality seafood product. The recent outbreak of an epidemic caused by a novel Carpione rhabdovirus (CAPRV) occurred in cultured golden pompano. To address it, a CAPRV enzyme-mediated one-step sample processing–reverse transcription–enzyme-mediated duplex exponential amplification (EmOSP-RT-EmDEA) detection system was developed. This innovative molecular diagnostic tool integrates enzyme-mediated one-step sample processing (EmOSP) with enzyme-mediated duplex exponential amplification (EmDEA) technology. Unlike traditional RPA-Cas12a detection methods, this system directly incorporates fluorophores into RNA components, eliminating the need for exogenous fluorescent probes while maintaining high sensitivity. It enables rapid, sensitive, and specific detection of CAPRV2023 across various sample types, including clinical, invasive, minimally invasive, and environmental specimens. Performance evaluation of the CAPRV2023 EmOSP-RT-EmDEA detection system against conventional diagnostic methods, such as TaqMan qPCR and traditional PCR, demonstrated superior sensitivity, with a detection limit as low as 4 copies/μL, and exceptional specificity. The optimized EmOSP protocol for nucleic acid extraction from fecal, hepatic, and water samples provided robust and reproducible results. The EmOSP-RT-EmDEA system achieved a detection rate of 68.14% in fecal samples, matching the performance of the gold-standard TaqMan qPCR assay. Full article