Search Results (565)

RNA viruses pose significant threats to global health, causing diseases such as COVID-19, HIV/AIDS, influenza, and dengue. These viruses are characterized by high mutation rates, rapid evolution, and the ability to evade traditional antiviral therapies, making effective treatment and prevention particularly challenging. In recent years, CRISPR/Cas13 has emerged as a promising antiviral tool due to its ability to specifically target and degrade viral RNA. Unlike conventional antiviral strategies, Cas13 functions at the RNA level, providing a broad-spectrum and programmable approach to combating RNA viruses. Its flexibility allows for rapid adaptation of guide RNAs to counteract emerging viral variants, making it particularly suitable for highly diverse viruses such as SARS-CoV-2 and HIV. This review discusses up-to-date applications of Cas13 in targeting a wide range of RNA viruses, including SARS-CoV-2, HIV, dengue, influenza, and other RNA viruses, focusing on its therapeutic potential. Preclinical studies have demonstrated Cas13’s efficacy in degrading viral RNA and inhibiting replication, with applications spanning prophylactic interventions to post-infection treatments. However, challenges such as collateral cleavage, inefficient delivery, potential immunogenicity, and the development of an appropriate ethical framework must be addressed before clinical translation. Future research should focus on optimizing crRNA design, improving delivery systems, and conducting rigorous preclinical evaluations to enhance specificity, safety, and therapeutic efficacy. With continued advancements, Cas13 holds great promise as a revolutionary antiviral strategy, offering novel solutions to combat some of the world’s most persistent viral threats. Full article

The presence of cognitive lapses in the post-COVID-19 period, particularly among younger individuals, suggests a potential genetic predisposition. This case–control study aimed to assess the association between neurodegeneration-associated genes and cognitive declines in the post-COVID-19 Armenian population under the age of 65. In addition, we examined other contributing factors, including depressive symptoms, hypovitaminosis D, vitamin B12 and B9 deficiencies, and some viral infections, as potential confounders or effect modifiers. A total of 162 participants (ages 19–65, Med = 43), who were exposed to SARS-CoV-2 in Armenia between 2020 and 2022, participated in this study. Standardized assessments, including the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and the Montreal Cognitive Assessment (MoCA), were used to evaluate cognitive functions and mental status, while the Patient Health Questionnaire-9 (PHQ-9) was utilized to assess depressive symptoms. Clinical interview data, comprising yes/no self-reports regarding the presence of cognitive problems and depressive symptoms, were also included. Genetic analysis identified copy number variations (CNVs) in the APP, PSEN1, PSEN2, MAPT, and GRN genes, while viral infections (HSV-1, HSV-2, CMV, EBV, HIV, SARS-CoV-2, Hepatitis A, B, and C) and vitamin D, B12, and B9 deficiencies were measured. Lower cognitive performance was associated with CNVs in PSEN1 (exons 1, 9, 12), GRN (exons 1, 6, 12), and MAPT (exons 2, 8), along with viral infections (HSV-1, HSV-2, HAV-2). The findings indicate that post-COVID-19 cognitive problems are multifactorial and are linked to genetic mutations, viral infections, age, gender, and folic acid deficiency. Full article

Coal combustion residues are increasingly viewed as alternative sources of rare earth elements (REEs), but their heterogeneous composition and post-depositional alteration complicate resource evaluation. This study analyzes 50 coal ash (CA) samples collected from a weathered dumpsite near Almaty, Kazakhstan, originating from power generation using coal from the Ekibastuz Basin. A multi-method approach—comprising bulk chemical characterization, unsupervised clustering, X-ray diffraction (XRD), scanning electron microscopy (SEM), and supervised machine learning (ML)—was applied to identify consistent indicators of REE enrichment. While conventional regression models failed to predict individual REE concentrations accurately, ML algorithms consistently highlighted vanadium (V) as the most robust predictor of ΣREE across Random Forest, XGBoost, and LASSO. This suggests that V may act as a geochemical proxy for REE-bearing phases, potentially due to co-retention in amorphous or ferruginous matrices. Despite compositional similarity among many samples, XRD and SEM revealed marked variability in phase structure and crystallinity, underscoring the limitations of bulk oxide data alone. These findings demonstrate that REE behavior in ash cannot be predicted deterministically, but ML can be used to screen for informative compositional signals. The proposed workflow may support the preliminary classification and valorization of heterogeneous ash materials in secondary resource strategies. Full article

The persistent contamination of aquatic environments by heavy metals, particularly Pb²⁺, Cd²⁺, and Cu^2+, poses a serious global threat due to their toxicity, persistence, and bioaccumulative behavior. In response, low-cost and eco-friendly adsorbents are being explored, among which CaCO₃-based biocomposites derived from mollusk shells have shown exceptional performance. In this study, a hybrid biocomposite composed of poly(vinyl alcohol) (PVA) and oyster shell-derived CaCO₃ was computationally investigated using Density Functional Theory (DFT) to elucidate the electronic and structural basis for its high metal-removal efficiency. Calculations were performed at the B3LYP/6-311++G(d,p), M05-2X/6-311+G(d,p), and M06-2X/6-311++G(d,p) levels using GAUSSIAN 16. Among them, B3LYP was identified as the most balanced in terms of accuracy and computational cost. The hybridization with CaCO₃ reduced the HOMO-LUMO gap by 20% and doubled the dipole moment (7.65 Debye), increasing the composite’s polarity and reactivity. Upon chelation with metal ions, the gap further dropped to as low as 0.029 eV (Cd²⁺), while the dipole moment rose to 17.06 Debye (Pb²⁺), signaling enhanced charge separation and stronger electrostatic interactions. Electrostatic potential maps revealed high nucleophilicity at carbonate oxygens and reinforced electrophilic fields around the hydrated metal centers, correlating with the affinity trend Cu²⁺ > Cd²⁺ > Pb²⁺. Fukui function analysis indicated a redistribution of reactive sites, with carbonate oxygens acting as ambiphilic centers suitable for multidentate coordination. Natural Bond Orbital (NBO) analysis confirmed the presence of highly nucleophilic lone pairs and weakened bonding orbitals, enabling flexible adsorption dynamics. Furthermore, NCI/RDG analysis highlighted attractive noncovalent interactions with Cu²⁺ and Pb²⁺, while FT-IR simulations demonstrated the formation of hydrogen bonding (O–H···O=C) and Ca²⁺···O coordination bridges between phases. Full article

Using the combination of Concentrated solar power (CSP) and calcium looping (CaL) technology is an effective way to solve the problems of intermittent solar energy, but calcium-based materials are prone to sintering due to the densification of the surface structure during high-temperature cycling. In this study, the enhancement mechanism of Co and Cr doping in terms of the adsorption properties of CaO was investigated by Density Functional Theory (DFT) calculations. The results indicate that Co and Cr doping shortens the bond length between metal and oxygen atoms, enhances covalent bonding interactions, and reduces the oxygen vacancy formation energy. Meanwhile, the O²⁻ diffusion energy barrier decreased from 4.606 eV for CaO to 3.648 eV for Co-CaO and 2.854 eV for Cr-CaO, which promoted CO₂ adsorption kinetics. The CO₂ adsorption energy was significantly increased in terms of the absolute value, and a partial density of states (PDOS) analysis indicated that doping enhanced the C-O orbital hybridization strength. In addition, Ca₄O₄ cluster adsorption calculations indicated that the formation of stronger metal–oxygen bonds on the doped surface effectively inhibited particle migration and sintering. This work reveals the mechanisms of transition metal doping in optimizing the electronic structure of CaO and enhancing CO₂ adsorption performance and sintering resistance, which provides a theoretical basis for the design of efficient calcium-based sorbents. Full article

Potentially toxic elements such as cadmium (Cd) in agricultural soils represent a global concern due to their toxicity and potential accumulation in the food chain. However, our understanding of cadmium’s complex sources and the mechanisms controlling its spatial distribution across diverse edaphic and geological contexts remains limited, particularly in underexplored agricultural regions. Our study aimed to assess the total accumulated Cd content in soils under avocado cultivation and its association with edaphic, geochemical, and geomorphological variables. To this end, we considered the total concentrations of other metals and explored their associations to gain a better understanding of Cd’s spatial distribution. We analyzed 26 physicochemical properties, the total concentrations of 22 elements (including heavy and trace metals such as As, Ba, Cr, Cu, Hg, Ni, Pb, Sb, Se, Sr, Tl, V, and Zn and major elements such as Al, Ca, Fe, K, Mg, and Na), and six geospatial variables in 410 soil samples collected from various avocado-growing regions in Peru in order to identity potential associations that could help explain the spatial patterns of Cd. For data analysis, we applied (1) univariate statistics (skewness, kurtosis); (2) multivariate methods such as Spearman correlations and principal component analysis (PCA); (3) spatial modeling using the Geodetector tool; and (4) non-parametric testing (Kruskal–Wallis test with Dunn’s post hoc test). Our results indicated (1) the presence of hotspots with Cd concentrations exceeding 3 mg·kg⁻¹, displaying a leptokurtic distribution (skewness = 7.3); (2) dominant accumulation mechanisms involving co-adsorption and cation competition (Na⁺, Ca²⁺), as well as geogenic co-accumulation with Zn and Pb; and (3) significantly higher Cd concentrations in Leptosols derived from Cretaceous intermediate igneous rocks (diorites/tonalites), averaging 1.33 mg kg⁻¹ compared to 0.20 mg·kg⁻¹ in alluvial soils (p < 0.0001). The factors with the greatest explanatory power (q > 15%, Geodetector) were the Zn content, parent material, geological age, and soil taxonomic classification. These findings provide edaphogenetic insights that can inform soil cadmium (Cd) management strategies, including recommendations to avoid establishing new plantations in areas with a high risk of Cd accumulation. Such approaches can enhance the efficiency of mitigation programs and reduce the risks to export markets. Full article

Background/Objectives: Cognitive impairment and vestibular dysfunction commonly co-occur in older adults and may share overlapping neuroanatomical pathways. Understanding their association may enhance the early identification of cognitive decline using clinically feasible vestibular assessments. This study aimed to examine the relationship between vestibular dysfunction and early cognitive impairment, assess the diagnostic accuracy of vestibular markers, and explore the association of subjective dizziness and balance measures with cognitive performance. Methods: Our cross-sectional study included 90 participants aged ≥60 years, classified into cognitively healthy, mild cognitive impairment (MCI), and early Alzheimer’s disease (AD) groups. Cognitive function was assessed using the MoCA and the MMSE; vestibular function was evaluated via posturography sway and horizontal vHIT gain. Subjective dizziness and balance were measured using the Dizziness Handicap Inventory (DHI), gait speed, and eyes-closed balance time. The data were analyzed using SPSS v24 with ANOVA, Pearson correlations, linear regression, and ROC curve analyses. Results: Significant group differences were found across the cognitive and vestibular scores (MoCA: p = 0.001. Sway: p = 0.001. vHIT: p = 0.001). vHIT gain and posturography sway independently predicted the MoCA and MMSE scores (adjusted R² = 0.68 and 0.65, respectively). The ROC analysis showed a strong diagnostic accuracy for posturography sway (AUC = 0.87) and vHIT gain (AUC = 0.82). Conclusions: Vestibular dysfunction is significantly associated with early cognitive impairment and may serve as a useful clinical marker for cognitive screening in older adults. Full article

Pepper anthracnose is a globally devastating fungal disease caused by Colletotrichum spp. In this study, we explored the molecular mechanisms underlying anthracnose resistance in Capsicum annuum by comparing a resistant variety 225 with a susceptible variety 307. Phenotypic analysis revealed that variety 225 displayed stronger resistance than variety 307. Through comparative transcriptome analysis and weighted gene co-expression network analysis (WGCNA), 17 gene modules were identified, among which the salmon module showed a strong association with resistance in variety 225. Within this module, 18 hub genes—including Ca59V2g00372.1 (CaTLP6), encoding a thaumatin-like protein (TLP)—were significantly upregulated upon infection. A genome-wide analysis identified 31 CaTLP genes in C. annuum, with members of group V (such as CaTLP6) exhibiting induced expression post-inoculation of Colletotrichum scovillei. Subcellular localization analysis indicated that group V CaTLP proteins were associated with the plasma membrane, suggesting a role in pathogen recognition. These findings highlight the significance of CaTLP genes, particularly those in group V, in pepper’s defense against anthracnose caused by C. scovillei and offer promising targets for breeding resistant cultivars. Full article

We report new medium-resolution spectroscopy covering the wavelength range from 0.6 to 2.4 $\mathsf{\mu }$m, as well as multi-epoch, multi-wavelength photometry, of the Class I high-mass embedded young stellar object Mol 12 (IRAS 05373+2349). It is embedded ($A_V\simeq 12$) in the centre of a dense core at a distance of 1.59 kpc from the Sun and has a total luminosity of $1.74\times {10}^3{L}_{\odot }$. The spectra show a large number of permitted atomic emission lines, mostly for Fe, H, C, N, and Ca, that originate in the inner zones of a very active protoplanetary disc and no photospheric absorption lines. Conspicuously, the He I line at 1.0830 $\mathsf{\mu }$m displays a complex P-Cygni profile. Also, the first overtone CO emission band-heads at 2.3 $\mathsf{\mu }$m are seen in emission. From the strengths of the principal emission lines, we determined the accretion rate and luminosity to be $\dot{M}\sim {10}^{-5}{M}_{\odot }$ y⁻¹ and $L_{\mathrm{acc}}\sim {10}^3{L}_{\odot }$, respectively. Decade-long light curves show a series of irregular brightness dips of more than four magnitudes in r, becoming shallower as the wavelength increases and disappearing at $\lambda >3\mathsf{\mu }$m. The colour–magnitude diagrams suggest the occurrence of a series of eclipses caused by the passage of small dust cloudlets in front of the star, producing more than 10 magnitudes of extra extinction. Full article

Titanium and its alloy scaffolds are widely utilized in clinical settings; however, their biologically inert surfaces and inherent mechanical characteristics impede osteogenesis and soft tissue integration, thereby limiting their application. Selective laser melting (SLM) was employed to fabricate scaffolds with matched cortical bone mechanical properties, achieving a composite coating of hydroxyapatite complexed with trace elements of silicon, strontium, and fluoride (mHA), along with type I collagen (Col I) and fibrinogen (Fg), thus activating the scaffold surface. Initially, we utilized the excellent adhesive properties of dopamine to co-deposit mHA and polydopamine (PDA) onto porous Ti-6Al-4V scaffolds, which was followed by immobilization of type I collagen and fibrinogen onto PDA. This bioinorganic/bioprotein composite coating, formed via PDA bonding, exhibits excellent stability. Moreover, in vitro cell experiments demonstrate excellent biocompatibility of the porous Ti-6Al-4V scaffold with composite bioactive coatings on its surface. Preosteoblasts (MC3T3-E1) and human keratinocytes (HaCaT) exhibit enhanced adhesion and proliferation activity, and the osteogenic performance of the scaffold is significantly improved. The PDA-mHA-Col I-Fg composite-coated porous titanium alloy scaffold holds significant promise in enhancing the efficacy of percutaneous bone transplantation and requires further investigation. Full article

Background: Silver nanoparticles (AgNPs) show promises as antimicrobial biomaterials with use for combating multidrug-resistant microorganisms, and they are widely used in healthcare, medicine, and food industries. However, traditional physicochemical synthesis methods often require harsh conditions and toxic reagents, generating harmful waste. The synthesis of AgNPs using plant-derived bioactive compounds offers an eco-friendly alternative to conventional methods. Methods: In this study, a bio-green approach was employed to synthesize AgNPs using ethanolic extracts from Antigonon leptopus leaves (EXT-AL). The synthesis was optimized under different pH conditions (5.5, 8.0, 10.0) and EXT-AL concentrations (10–200 μg/mL). Antibacterial activity was evaluated against Escherichia coli and Staphylococcus aureus, and cytotoxicity was assessed in HeLa, CaCo-2, T731-GFP, and HaCaT cell lines. Results: UV-Vis spectroscopy confirmed nanoparticle formation, with a surface plasmon resonance peak at 410 nm. Alkaline conditions (pH 10.0) favored the formation of smaller, spherical AgNPs. Characterization by DLS, TEM, and AFM revealed uniform nanoparticles with a hydrodynamic diameter of 93.48 ± 1.88 nm and a zeta potential of −37.80 ± 1.28 mV. The AgNPs remained stable in Milli-Q water but tended to aggregate in PBS, DMEM, and MHB media. Antibacterial assays demonstrated significant bactericidal activity against Escherichia coli and Staphylococcus aureus at 3.9 μg/mL (Ag⁺ equivalent). Cytotoxicity tests showed no toxicity to HeLa, T731-GFP, CaCo-2, or HaCaT cells at concentrations ≥ 7.8 μg/mL after 24 h. Conclusions: These findings highlight Antigonon leptopus extract as a sustainable and cost-effective resource for AgNPs synthesis, with strong antimicrobial properties and potential biomedical applications. Full article

The CRISPR–Cas system has transformed molecular biology by providing precise tools for genome editing and pathogen detection. Originating from bacterial adaptive immunity, CRISPR technology identifies and cleaves genetic material from pathogens, thereby preventing infections. CRISPR–Cas9, the most widely utilized variant, creates double-stranded breaks in the target DNA, enabling genetic disruptions or edits. This approach has shown significant potential in antiviral therapies, addressing chronic infections, such as HIV, SARS-CoV-2, and hepatitis viruses. In HIV, CRISPR–Cas9 edits the essential viral genes and disrupts latent reservoirs, while CCR5 gene modifications render the T cells resistant to viral entry. Similarly, SARS-CoV-2 is targeted using CRISPR–Cas13d to inhibit the conserved viral genes, significantly reducing viral loads. Hepatitis B and C treatments leverage CRISPR technologies to target conserved genomic regions, limiting replication and expression. Emerging innovations, such as the PAC-MAN approach for influenza and base-editing systems to reduce off-target effects, further highlight the therapeutic versatility of CRISPR. Additionally, advances in Cas12a and Cas13 have driven the development of diagnostic platforms like DETECTR and SHERLOCK, which provide rapid and cost-effective viral detection. Innovative tools like AIOD-CRISPR enable accessible point-of-care diagnostics for early viral detection. Experimental approaches, such as targeting latent HSV-1 reservoirs, highlight the transformative potential of CRISPR in combating persistent infections. Full article

This study employs density functional theory (DFT) simulations to systematically investigate the structural and optoelectronic modifications induced by the substitution of metal ions (Mg²⁺, Ca²⁺, Mn²⁺, Fe²⁺/³⁺, Co²⁺, and Ni²⁺) in kaolinite. First-principles calculations reveal distinct substitution behaviors: Na-Ni (II)-1 exhibits the lowest cell energy, indicating superior structural stability, while Na-Mn (II)-1 demonstrates the most favorable substitution energy (−5.44 eV). XRD simulations of divalent substitutions show a positive correlation between atomic number and diffraction intensity at 8.778° and 9.774°, suggesting a spectral marker for substitution detection. Electronic structure analysis identifies significant bandgap reduction, with Na-Fe (II)-4 achieving an ultranarrow gap of 1.014 eV, attributed to spin-polarized d-orbital contributions. X-ray absorption fine-structure (XAFS) simulations further reveal metal-specific bond elongation, with Fe³⁺ substitutions preserving near-pristine coordination distances. These findings establish a comprehensive framework linking metal substitution to structural distortion and optoelectronic response, providing theoretical insights for optimizing kaolinite-based material properties through computational feature extraction. Full article

Herein, we present in-depth investigations of the biological activities of a CaO/NiO nanocomposite synthesized via a sustainable eco-friendly approach, utilizing Citrus limonium fruit extract as a natural stabilizing and facilitating agent. The efficacy of the nanocomposite is compared with those of individual CaO and NiO nanoparticles. X-ray diffraction analysis confirms the cubic phase of CaO as well as NiO within a unified matrix, demonstrating a refined crystallite size of 48 nm, which is smaller than that of the individual nanoparticles. FTIR study substantiates the occurrence of strong Ca-O-Ni-O bonds, along with CO₃²⁻, C–H, and CH₂ bonds. The CaO, NiO, and CaO/NiO samples exhibit bandgap values of 1.70, 3.46, and 3.44 eV, respectively. Surface morphology analysis reveals that CaO/NiO holds a well-defined heterostructure with porous morphology. An XPS study confirms that Ca and Ni elements exist in the 2+ oxidation state in the CaO/NiO. The nanocomposite exhibits superior antibacterial activity, with inhibition zones of 24.3 mm against Bacillus subtilis and 20.6 mm against Salmonella typhi, and MIC values of 23.4 and 46.8 µg/mL, respectively. It also demonstrates strong antioxidant potential, with IC₅₀ values of 96.8 ± 0.4 µg/mL (DPPH) and 91.8 ± 0.1 µg/mL (superoxide anion). Furthermore, it shows the lowest IC₅₀ for α-amylase (98.6 ± 0.7 µg/mL) and strong α-glucosidase inhibition (81.96 ± 0.5 µg/mL). Consequently, this insightful study reveals how biogenic synthesis helps develop high-performance multifunctional CaO/NiO nanocomposites for biomedical applications. Full article

Over the past 3 years, several kidney complications in children with severe involvement by SARS-CoV-2 have been described. However, literature data are still lacking regarding possible kidney injury in children with paucisymptomatic SARS-CoV-2 infection. Thus, we retrospectively evaluated renal function in those patients. Children between 3 and 18 years, without any renal disease, with previous paucisymptomatic SARS-CoV-2 infection from May 2020 to March 2022, were recruited at our post-COVID-19 outpatient clinic. We retrospectively collected: Glomerular filtration rate, Fractional-excretion-of-sodium (FENa), tubular-reabsorption-of-phosphate (TRP), calcium-creatinine-urine ratio (CaU/CrU); proteinuria/m²/day and microhematuria by urine cytofluorometry. A total of 148 children were enrolled after a median period of 3 (IQR 6) months after infection. Twenty-six patients (17.6%) had reduced GFR, fifty (33.9%) had hyperfiltration, eleven (7.4%) had abnormal FENa and/or TRP, twenty-two (14.9%) had hypercalciuria, seventy-eight (52.7%) had pathological daily proteinuria. Microhematuria was found in sixteen (10.9%) subjects. Hyperfiltration was more prevalent among males (38.9% vs. 22.4%, p = 0.027); CaU/CrU [median 0.08 (IQR 0.09) vs. 0.13 (IQR 0.13) p = 0.003] was significantly higher in females. Our data suggest that SARS-CoV-2 could determine, in a significant proportion of children, kidney damage characterized by hyperfiltration, proteinuria, and hematuria, warranting strict follow-up in these patients. Full article