Search Results (7,182)

The detection of biological markers is critical not only for the early diagnosis of cancer but also for adjustments in antitumor therapy. Rapid, sensitive, and selective detection and monitoring of the content of specific biomarkers in real time are key to point-of-care testing diagnostics. We report the detection of heat shock proteins by fluorescence immunoassay with the appropriate phage antibodies, with a minimum detection limit of 1 ng/mL. The fluorescence immunoassay data were confirmed by dot immunoassay and by circular dichroism studies. The results of the study may help in the adaptation of the fluorescence immunoassay to cancer diagnostics. Full article

Carcass growth and development are crucial evaluation indicators influencing the economic efficiency of goats (Capra hircus). This study aimed to screen the nucleotide variation sites (SNPs) of the APOE gene in Guizhou white goats and explore the correlation between APOE gene variations and body size traits, as APOE had been identified as a key candidate gene regulating growth and development in this breed through transcriptome sequencing screening. A total of 324 Guizhou white goats were used in this study for SNP detection, population genetic analysis, real-time fluorescence quantitative PCR (RT-qPCR) and association analysis. The results showed that one nucleotide mutation site (g.353 A > G) was detected in the APOE gene, which yielded two alleles (A and G) and three genotypes (AA, AG and GG). The site exhibited moderate polymorphism and conformed to Hardy–Weinberg equilibrium. The mRNA expression level of APOE in longissimus dorsi muscle was significantly higher in males than in females. Association analysis revealed a sex-specific effect of this locus on body size traits. The A allele and AA genotype were significantly associated with increased body weight and heart girth in females, whereas no significant effect was detected in males. Therefore, the identified APOE gene mutation site can serve as a candidate molecular marker for the early selection of growth traits in Guizhou white goats. Full article

Excessive accumulation of copper ions (Cu²⁺) in the environment and biological systems poses severe risks to ecological balance and human health, necessitating accurate detection and monitoring of Cu²⁺. Schiff base derivatives with favorable optical properties provide an efficient strategy for copper ion recognition. In this paper, fluorescent probe L (5-methyl-2-hydroxybenzaldehyde-(7-diethylaminocoumarin-3-formyl) hydrazone) was synthesized through a three-step reaction using 4-diethylaminosalicylaldehyde and diethyl malonate as starting materials. The structure of probe L was confirmed by melting point analysis, infrared spectroscopy, and nuclear magnetic resonance. Single-crystal X-ray analysis revealed that probe L crystallized into a triclinic lattice with space group $P_1^{-}$. Optical investigations, including UV–Vis spectroscopy, fluorescence spectroscopy, and aggregation-induced emission studies, demonstrated highly sensitive and selective fluorescence “turn-off” behavior of probe L towards Cu²⁺ ions in DMSO, with negligible interference from other metal ions. Job’s plot and crystallographic analysis revealed a 1:1 binding stoichiometry between probe L and Cu²⁺, forming the complex [Cu(L)]. Fluorescence titration experiments revealed a binding constant (K_b) of 5.2 × 10⁶ L/mol and a detection limit of 7.8 × 10⁻⁷ mol/L, indicating excellent sensitivity. These results suggest that probe L has considerable promise for Cu²⁺ detection in aqueous environments, with potential applications in environmental monitoring and public health protection. Full article

Albumin is an important biomarker in biological fluids and plays a critical role, particularly in the diagnosis of renal dysfunction. Therefore, the sensitive detection of low concentrations of albumin in urine is of great importance. In this study, a composite nanohydrogel modified with carbon dots has been developed for the selective detection of albumin from human urine. The composite nanohydrogels were synthesised using a molecular imprinting technique specifically designed to recognise albumin. Characterisation studies were conducted using ZetaSizer, SEM, EDX, CLSM and ATR-FTIR methods. The albumin-binding capacities of the carbon dots (C-Dots) and synthesised composite nanohydrogels were evaluated using fluorescence spectroscopy. The effects of different concentration conditions on binding efficiency were systematically investigated. Selectivity studies have shown that albumin-imprinted nanohydrogels can detect target molecule albumin four times more selectively than competitive molecules, Hb and IgG. Imprinting efficiency was estimated by comparing the signals of albumin obtained from non-imprinted and albumin-imprinted composite nanohydrogels. Finally, artificial urine samples mimicking real biological environment conditions were examined to evaluate matrix effect on the albumin detection. The repeatability and long-term stability of albumin detection, performed with four consecutive and six-month measurements, was evaluated using the %RSD value, confirming that the albumin determination performance was maintained. Full article

Sporulation represents a complex metabolic reprogramming process in bacteria. In this study, we used CRISPR-Cpf1 to knock out spoIIE and rsfA in Bacillus licheniformis. The ΔspoIIE strain completely lost sporulataion capacity, while ΔrsfA showed a 25% reduction. Although viable cell counts decreased by 80.7% and 45.7%, respectively, glucose consumption and 2,3-butanediol synthesis remained unchanged, and acetoin synthesis increased by 19% in ΔspoIIE. Per-cell metabolic rates were significantly enhanced: glucose uptake increased 2.7–3.4-fold, acetoin synthesis 2.3–4.2-fold, 2,3-butanediol synthesis 1.7-fold, and heterologous protein expression 10–15-fold. These findings demonstrate that blocking sporulation liberates metabolic resources and enhances the specific productivity of vegetative cells, providing a strategy for engineering high-performance B. licheniformis cell factories. Full article

This study proposes a four-dimensional Historical Building Defect Information Modeling (HBDIM) framework designed to support the documentation, diagnosis, and conservation of deteriorated historic stucco elements. The framework integrates multi-source digital documentation techniques, including terrestrial laser scanning (TLS), high-resolution photogrammetry, and automated total station measurements with laboratory-based material diagnostics to create a unified digital environment for defect detection and conservation assessment. The approach was applied to the Baron Empain Palace in Egypt as a representative case study of complex architectural heritage affected by material deterioration. Within the HBDIM workflow, point cloud processing and defect-oriented information modeling were used to identify and spatially localize deterioration features such as cracking, erosion, and material loss. Laboratory investigations—including computed tomography (CT), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray fluorescence (XRF)—were conducted to evaluate the effectiveness of calcium hydroxide nanoparticle consolidation treatments and to relate microstructural material behavior to spatially mapped defects within the digital model. Mechanical testing demonstrated a significant improvement in material performance, with treated stucco samples exhibiting an average compressive strength increase of approximately 69.06% compared to untreated specimens. The results demonstrate that integrating digital documentation, defect-oriented modeling, and material diagnostics within a four-dimensional framework provides a robust platform for linking geometric deterioration patterns with material-level conservation performance. By embedding diagnostic data and treatment outcomes within a temporally structured digital model, the HBDIM approach supports preventive conservation strategies, long-term monitoring, and data-driven decision-making in sustainable heritage management. Full article

Light-based diagnostic and therapeutic approaches are increasingly important in modern biomedicine, with organic dyes emerging as versatile optical agents due to their tunable photophysical properties. Precise control over absorption and emission characteristics has enabled their application in fluorescence, photoacoustic, and Raman imaging, as well as in photodynamic and photothermal therapies. However, challenges related to biocompatibility, aqueous stability, and in vivo performance remain critical for clinical translation. Organic dyes that absorb in the near-infrared region are particularly attractive because of their deeper tissue penetration and reduced background interference. This review highlights key structure property relationships of organic dyes and summarizes current design strategies, including chromophore modification, peripheral functionalization for water solubility, and self-assembled nanotheranostic systems. Recent biomedical applications in cancer diagnosis and therapy, bacterial detection, and imaging-guided treatment are discussed, along with future directions for advancing dye-based technologies in healthcare. Full article

Background and Objectives: Burn wounds are associated with delayed healing, infection, and pathological scarring. Effective repair requires tightly regulated immune and oxidative stress responses, including macrophage polarization. This study evaluated the association of the photosensitizer Rose Bengal, delivered in a hydrogel vehicle, with macrophage polarization and oxidative stress after burn injury. Materials and Methods: Three female red Duroc pigs underwent full-thickness contact burns followed by excision and autografting. Wounds received 20% Pluronic F-127 hydrogel containing 0.1% Rose Bengal sodium, hydrogel alone, or PBS (phosphate-buffered saline) on days 1, 7, and 14 post-burn. Biopsies from days 7 and 120 were analyzed by immunohistochemistry for pan-macrophage marker, CD206 (M2 macrophages), CD3E (T-cell infiltration), and 4-hydroxynonenal (4-HNE; oxidative stress marker). Mean fluorescence intensity was analyzed using two-way ANOVA with Tukey’s post hoc test (mean ± SD, p < 0.05). Results: At day 120, Rose Bengal treatment showed higher pan-macrophage expression (0.80 ± 0.07) compared with PBS (0.62 ± 0.10; p = 0.0034), whereas the difference versus hydrogel (0.68 ± 0.07; p = 0.0628) was not significant. CD206 expression was similarly higher in Rose Bengal-treated wounds (0.77 ± 0.06) compared with PBS (0.62 ± 0.05; p = 0.0277); hydrogel also differed from PBS (p = 0.0287), without a difference between hydrogel and Rose Bengal. For CD3E, a significant main effect of treatment was observed (F(2,12) = 8.346, p = 0.0054), with lower values in Rose Bengal versus PBS at day 120 (p = 0.0360). No differences in 4-HNE were detected. Conclusions: Rose Bengal–hydrogel treatment was associated with increased macrophage presence and enhanced M2 polarization without increased T-cell infiltration. Effects were significant versus PBS but not hydrogel, suggesting Rose Bengal may contribute to a pro-regenerative immune microenvironment without excessive adaptive activation. Full article

Abies georgei var. smithii (Viguie & Gaussen) is a dominant conifer along the southeastern margin of the Qinghai–Tibet Plateau, where heart rot often develops covertly, complicating forest health monitoring and disease management. Fomitopsis subpinicola B.K. Cui, M.L. Han & Shun Liu is an important causal agent of heart rot affecting A. georgei var. smithii in this region, yet rapid, field-deployable molecular diagnostics of this pathogen remain limited. Here, we developed and evaluated two TEF1α-based isothermal platforms for specific detection of F. subpinicola: RAA and LAMP. To reduce potential cross-reactivity, TEF1α sequences from representative taxa within the F. pinicola species complex and closely related non-complex species were aligned for primer/probe design. Candidate RAA primers were screened by gel electrophoresis to select an optimal pair, and two LAMP primer sets were compared by specificity testing to identify the best-performing set. Both assays specifically detected F. subpinicola with no cross-amplification in the tested non-target fungi. Limits of detection were 9.97 copies/μL for fluorescent RAA (25 min), 9.97 × 10² copies/μL for RAA-LFD (15 min), and 9.97 × 10³ copies/μL for LAMP (35 min). In 30 increment core samples from A. georgei var. smithii, all methods consistently detected samples with obvious decay, while fluorescent RAA additionally yielded positives in some apparently asymptomatic samples, indicating promise for early or low-abundance screening. Together, these assays constitute a tiered and application-oriented detection system, enabling flexible selection of diagnostic approaches according to sensitivity requirements, operational conditions, and field surveillance needs for heart rot of A. georgei var. smithii. Full article

All forms of neural communications, from cognition to emotion, are regulated by neurotransmitters, which are otherwise the chemical language of the brain. Precise detection of these neurotransmitters is essential for the perception of neurophysiology and diagnosis of neurodegenerative diseases as well. Among the existing techniques for the detection of these molecules, fluorescence sensing is evolving as a powerful approach in terms of high sensitivity, rapid response, and real-time visualization of the chemical events occurring in the neural system. In recent years, nanomaterials have transformed this field by integrating tunable optical properties, excellent photostability, and modifiable surface chemistry into biocompatible nanostructures. We summarize the recent advances of these architectures to show how the material type and dimensionality, as well as the surface functionality, play roles in sensing through the mechanisms of Förster resonance energy transfer (FRET), photoinduced electron transfer (PET), inner filter effect (IFE), and aggregation-induced emission (AIE). The discussion has also been extended to the correlation of fluorescence modulation with the selectivity and sensitivity in the mechanism-to-function relationship. The potential utility of such innovative technologies, including artificial intelligence, spectral deconvolution analysis via big data algorithms, and chip-integrated sensing, was explored as a means to enable real-time neurochemical detection. This converging area of nanotechnology and neuroscience leaves a mark not just in analytical accuracy, but also parallels human brain rhythms. Full article

In order to achieve rapid and qualitative detection of soluble heavy metal ions, nitrogen-doped fluorescent carbon quantum dots (N-CQDs) were synthesized using chitin extracted from shrimp and crab shells as the carbon source. The structural, morphological, and optical properties of the synthesized N-CQDs were systematically characterized using transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), Fourier transform infrared spectroscopy (FTIR), Raman, X-ray photoelectron spectroscopies (XPS), ultraviolet-visible (UV-Vis) absorption spectroscopy and fluorescence spectroscopy. The resulting N-CQDs exhibited a carbonization yield of 54.46% and a fluorescence quantum yield of 34.33%. Their morphology, structure and optical properties were thoroughly characterized using a range of analytical techniques. The synthesized N-CQDs exhibited excellent fluorescence properties, and remarkable stability. When applied for metal ion detection, the N-CQDs displayed a distinct and selective fluorescence quenching response exclusively toward Fe³⁺ ions. The detection limit for Fe³⁺ at room temperature was 4.04 μmol/L. Furthermore, due to the inherent nitrogen present in the acetyl amino groups of chitin, nitrogen doping was achieved without the need for external dopants during the hydrothermal synthesis process. Owing to their high stability, low cost and low toxicity, the N-CQDs synthesized in this study provide a promising fluorescence sensing platform with excellent selectivity for Fe³⁺ detection, achieved through precise control of surface functional groups. Full article

Toxoplasma gondii and Neospora caninum are closely related apicomplexan parasites of veterinary and public health importance. T. gondii is a zoonotic pathogen for which cats are the definitive host, whereas N. caninum is a major cause of reproductive losses in cattle, with dogs acting as the definitive host. Data on exposure in pet animals in Thailand remain limited. This study investigated seroprevalence and associated risk factors of T. gondii and N. caninum in pet cats and dogs in Pathum Thani Province, an urban area adjacent to Bangkok. Between June 2020 and July 2021, serum samples were collected from 169 owned animals, including 86 cats and 83 dogs, participating in a mobile sterilization program. Antibodies were detected using the indirect fluorescent antibody test (IFAT), and animal characteristics, behaviors, and environmental factors were obtained via owner questionnaires. Serological evidence of exposure to both parasites was detected. Antibodies against T. gondii were detected in 4.73% (8/169) of animals, including 4.65% (4/86) of cats and 4.82% (4/83) of dogs. For N. caninum, the overall seroprevalence was 10.06% (17/169), with a higher prevalence in dogs (15.66%, 13/83) than in cats (4.65%, 4/86). No significant risk factors were identified for T. gondii or N. caninum infection in either cats or dogs (p > 0.05). Full article

Fluorescent metal nanoclusters show great promise in heavy metal ion sensing. Herein, a bimetallic nanocluster (GSH-Au/Ag NCs) with orange fluorescence was synthesized through a facile one-pot method. The synthesized GSH-Au/Ag NCs displayed optimal excitation and emission peaks at 275 and 610 nm, respectively. The incorporation of silver can enhance the fluorescence of metal nanoclusters. The fluorescence of as-synthesized GSH-Au/Ag NCs can be significantly quenched by Hg²⁺ and Cu²⁺, and a “on–off” fluorescent probe was designed. The detection conditions, including pH and the concentration of the probe, were optimized. The respective detection limits for Hg²⁺ and Cu²⁺ ions under optimal detection conditions are estimated to be 40 nM and 33 nM, over the linear range of 100–1200 nM. Furthermore, a ratiometric fluorescent probe was prepared by mixing quinine sulfate and as-synthesized GSH-Au/Ag NCs. Hg²⁺ and Cu²⁺ can effectively quench the red fluorescence of GSH-Au/Ag NCs, whereas the blue fluorescence of quinine sulfate remains invariant. This leads to measurable changes in the RGB values of the resulting fluorescence images. The ratio (R/B) exhibits a linear relationship with the concentration of Hg²⁺ and Cu²⁺, enabling the determination of its concentration by analyzing RGB values in fluorescence images. This visual detection method significantly reduces both assay time and cost, making it suitable for on-site detection of heavy metal ions in water samples. Full article

Background and Objectives: Caries in primary teeth are characterized by rapid and often asymptomatic progression, with early dentin involvement and potential extension to the pulp. Untreated lesions may lead to complications that affect the development of the permanent dentition. The aim of this prospective study was to evaluate the clinical and biological effectiveness of chemo-mechanical controlled caries excavation using Brix 3000 compared to conventional treatment in primary molars over an 18-month follow-up period. Materials and Methods: A total of 82 children aged 4–7 years were included, each presenting with at least one carious lesion in a primary molar classified as International Caries Detection and Assessment System (ICDAS II) code 05 or 06. The carious lesions were divided into two groups according to the method of excavation: Group 1 (control), which contained 40 lesions treated with conventional bur excavation, and Group 2, which contained 42 lesions treated with chemo-mechanical excavation using Brix 3000. In all cases, excavation was controlled using a fluorescence-based device (ProFace). Clinical performance was evaluated using an assessment protocol adapted from the FDI (Fédération Dentaire Internationale) clinical criteria for the evaluation of direct and indirect restorations, with particular emphasis on biological outcomes. Follow-up examinations were performed after 1 week and 1, 3, 6, 12, and 18 months, and included radiographic evaluations. Results: After 18 months, chemo-mechanical caries excavation with Brix 3000 demonstrated a biological success rate of 100%, with no reported acute symptoms or complications. Esthetic criteria showed a success rate of 65% at 18 months, while anatomical and functional criteria demonstrated success rates of 95% and 98%, respectively. In the conventional bur excavation group, biological success reached 100%, while the esthetic, anatomical, and functional success rates were 61.3%, 93.5%, and 100%, respectively. No significant differences were observed between groups (p > 0.05). Conclusions: Chemo-mechanical controlled caries excavation using Brix 3000 represents a clinically effective and biologically reliable alternative to conventional caries excavation for the treatment of carious lesions in primary molars. Full article

Rare earth elements (REEs), located in the IIIB group of the periodic table, can be detected in very small quantities by sensitive detection techniques. REE labeling technologies utilize fluorescent labeling, magnetic labeling, atomic fluorescence labeling, fluorescence resonance energy transfer (FRET) labeling and radiolabeling. Widely used immunoassays related to REE-labeled technologies include time-resolved fluorescence immunofluorescence assay (TRFIA), inductively coupled plasma–mass spectrometry (ICP–MS)-based immunoassays, mass spectrometry flow-through (CyTOF), and upconversion nanoparticles (UCNPs). REE-labeled immunoassays have been widely used in various fields, such as biological analysis, biomarker detection and analysis of food detection techniques, as these assays can use low quantities of biological tissue, exhibit stability, can label materials, lack radioactivity and show multidetection capability. To provide researchers with a deeper understanding of the immunoassay technique used to label rare earth elements, this paper reviews its labeling principle, detection technology, and application. Full article