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DNA/RNA-gold nanoparticle (DNA/RNA-AuNP) nanoprobes have been widely employed for nanobiotechnology applications. Here, we discover that both thiolated and non-thiolated DNA/RNA can be efficiently attached to AuNPs to achieve high-stable spherical nucleic acid (SNA) within minutes under a domestic microwave (MW)-assisted heating-dry circumstance. Further studies show that for non-thiolated DNA/RNA the conjugation is poly (T/U) tag dependent. Spectroscopy, test strip hybridization, and loading counting experiments indicate that low-affinity poly (T/U) tag mediates the formation of a standing-up conformation, which is distributed in the outer layer of SNA structure. In further application studies, CRISPR/Cas9-sgRNA (136 bp), SARS-CoV-2 RNA fragment (1278 bp), and rolling circle amplification (RCA) DNA products (over 1000 bp) can be successfully attached on AuNPs, which overcomes the routine methods in long-chain nucleic acid-AuNP conjugation, exhibiting great promise in biosensing and nucleic acids delivery applications. Current heating-dry strategy has improved traditional DNA/RNA-AuNP conjugation methods in simplicity, rapidity, cost, and universality. Simple methods for attaching polynucleotides to gold nanoparticles are of interest for simplifying conjugation in a range of applications. Here, the authors report a microwave heating-based method for the fast, one-step attachment of a range of thiolated or non-thiolated DNA and RNA to gold nanoparticles.

Nucleic acids are not only essential biomolecules that drive critical life processes such as growth, development, reproduction, inheritance, and mutation, but also serve as significant markers for disease diagnosis, pathogen identification, and cancer screening. Nevertheless, several challenges have hindered the widespread use of nucleic acids in biomedicine, such as susceptibility to degradation, limited cellular uptake efficiency, potential toxicity, and uncontrollable activity. Photo‐regulation offers an effective solution to address these challenges. It allows for the precise control of nucleic acid structure and function and enhances the stability and safety of their application in biomedicine. In this review, we systematically review the structural characteristics of the three primary photosensitive groups commonly used in the regulation of nucleic acid molecules (i.e., photocleavable molecules, photoisomerization molecules, and photo‐crosslinking molecules) under light irradiation. Subsequently, recent research advances in the development and application of photo‐modulation strategies based on these photosensitive molecules in antisense oligonucleotides, RNA interference, nucleic acid amplification, and CRISPR/Cas systems are outlined. Finally, we discuss the challenges faced in the widespread application of these photo‐regulatory strategies and outline potential future directions for their development. The initial section of this review summaries the common photosensitive motifs—photo‐cleavable, photoisomerization, and photo‐crosslinking molecules—that are employed to regulate the function of nucleic acids. The subsequent part delineates the application of established photo‐modulation techniques in regulating antisense oligonucleotides, RNA interference, nucleic acid amplification, and the CRISPR/Cas system. Lastly, the challenges and future directions for the application of those photosensitive nucleic acid molecules are discussed.

Background Exploration of adaptive evolutionary changes at the genetic level in vaginal microbial communities during different stages of cervical cancer remains limited. This study aimed to elucidate the mutational profile of the vaginal microbiota throughout the progression of cervical disease and subsequently establish diagnostic models. Methods This study utilized a metagenomic dataset consisting of 151 subjects classified into four categories: invasive cervical cancer (CC) ( n  = 42), cervical intraepithelial neoplasia (CIN) ( n  = 43), HPV-infected (HPVi) patients without cervical lesions ( n  = 34), and healthy controls ( n  = 32). The analysis focused on changes in microbiome abundance and extracted information on genetic variation. Consequently, comprehensive multimodal microbial signatures associated with CC, encompassing taxonomic alterations, mutation signatures, and enriched metabolic functional pathways, were identified. Diagnostic models for predicting CC were established considering gene characteristics based on single nucleotide variants (SNVs). Results In this study, we screened and analyzed the abundances of 18 key microbial strains during CC progression. Additionally, 71,6358 non-redundant mutations were identified, predominantly consisting of SNVs that were further annotated into 25,773 genes. Altered abundances of SNVs and mutation types were observed across the four groups. Specifically, there were 9847 SNVs in the HPV-infected group and 14,892 in the CC group. Furthermore, two distinct mutation signatures corresponding to the benign and malignant groups were identified. The enriched metabolic pathways showed limited similarity with only two overlapping pathways among the four groups. HPVi patients exhibited active nucleotide biosynthesis, whereas patients with CC demonstrated a significantly higher abundance of signaling and cellular-associated protein families. In contrast, healthy controls showed a distinct enrichment in sugar metabolism. Moreover, biomarkers based on microbial SNV abundance displayed stronger diagnostic capability (cc.AUC = 0.87) than the species-level biomarkers (cc.AUC = 0.78). Ultimately, the integration of multimodal biomarkers demonstrated optimal performance for accurately identifying different cervical statuses (cc.AUC = 0.86), with an acceptable performance (AUC = 0.79) in the external testing set. Conclusions The vaginal microbiome exhibits specific SNV evolution in conjunction with the progression of CC, and serves as a specific biomarker for distinguishing between different statuses of cervical disease.

The regulation of CRISPR‒Cas activity is critical for developing advanced biotechnologies. Optical control of CRISPR‒Cas system activity can be achieved by modulation of Cas proteins or guide RNA (gRNA), but these approaches either require complex protein engineering modifications or customization of the optically modulated gRNAs according to the target. Here, we present a method, termed photocleavable phosphorothioate DNA (PC&PS DNA)-mediated regulation of CRISPR‒Cas activity (DNACas), that is versatile and overcomes the limitations of conventional methods. In DNACas, CRISPR‒Cas activity is silenced by the affinity binding of PC&PS DNA and restored through light-triggered chemical bond breakage of PC&PS DNA. The universality of DNACas is demonstrated by adopting the PC&PS DNA to regulate various CRISPR‒Cas enzymes, achieving robust light-switching performance. DNACas is further adopted to develop a light-controlled one-pot LAMP-BrCas12b detection method and a spatiotemporal gene editing strategy. We anticipate that DNACas could be employed to drive various biotechnological advances. CRISPR systems are powerful tools for gene editing and diagnostics, but their regulation is challenging. Here, the authors present DNACas, a light-controlled method using photocleavable phosphorothioate DNA to modulate CRISPR activity, enabling precise gene editing and one-pot diagnostic detection.

CRISPR-based nucleic acid detection assays offer a potent and dependable tool in modern nucleic acid detection, owing to their high specificity, rapidity, sensitivity, ease of use, and broad applicability.The combination of the CRISPR system and nucleic acid amplification technology has transformed the modern biomedical landscape, markedly augmenting the specificity of nucleic acid amplification, thereby advancing the field of precision medicine.The one-pot nucleic acid detection assay based on the CRISPR system realizes the integration of nucleic acid amplification and CRISPR detection into a single reaction tube, which not only simplifies the experimental operations but also significantly reduces the risk of aerosol contamination. The integration of nucleic acid amplification (NAA) with the CRISPR detection system has led to significant advancements and opportunities for development in molecular diagnostics. Nevertheless, the incompatibility between CRISPR cleavage and NAA has significantly impeded the commercialization of this technology. Currently, several one-pot detection strategies based on CRISPR systems have been devised to address concerns regarding aerosol contamination risk and operational complexity associated with step-by-step detection as well as the sensitivity limitation of conventional one-pot methods. In this review, we provide a comprehensive introduction and outlook of the various solutions of the one-pot CRISPR assay for practitioners who are committed to developing better CRISPR nucleic acid detection technologies to promote the progress of molecular diagnostics. The integration of nucleic acid amplification (NAA) with the CRISPR detection system has led to significant advancements and opportunities for development in molecular diagnostics. Nevertheless, the incompatibility between CRISPR cleavage and NAA has significantly impeded the commercialization of this technology. Currently, several one-pot detection strategies based on CRISPR systems have been devised to address concerns regarding aerosol contamination risk and operational complexity associated with step-by-step detection as well as the sensitivity limitation of conventional one-pot methods. In this review, we provide a comprehensive introduction and outlook of the various solutions of the one-pot CRISPR assay for practitioners who are committed to developing better CRISPR nucleic acid detection technologies to promote the progress of molecular diagnostics.

CRISPR diagnostics based on nucleic acid amplification faces barriers to its commercial use, such as contamination risks and insufficient sensitivity. Here, we propose a robust solution involving optochemical control of CRISPR RNA (crRNA) activation in CRISPR detection. Based on this strategy, recombinase polymerase amplification (RPA) and CRISPR-Cas12a detection systems can be integrated into a completely closed test tube. crRNA can be designed to be temporarily inactivated so that RPA is not affected by Cas12a cleavage. After the RPA reaction is completed, the CRISPR-Cas12a detection system is activated under rapid light irradiation. This photocontrolled, fully closed CRISPR diagnostic system avoids contamination risks and exhibits a more than two orders of magnitude improvement in sensitivity compared with the conventional one-pot assay. This photocontrolled CRISPR method was applied to the clinical detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA, achieving detection sensitivity and specificity comparable to those of PCR. Furthermore, a compact and automatic photocontrolled CRISPR detection device was constructed.

The objective of this work was to analyze the effect of Thidiazuron (TDZ) treatment on floral initiation, flowering time, ornamental characteristics and physiological metabolism of potted Dendrobium nobile. Three TDZ concentrations (200, 500 and 1000 mg L−1) were applied as solution to water the root zone of the plants. Control plants (plants watered with water) showed a good vegetative development but no floral branches. TDZ greatly influenced the flowering process. For all the tested TDZ concentrations, the first flower bud occurred at 55–60 days after the last irrigation (DAI), the highest TDZ concentration showing the major delay in its occurrence. The initial flowering (30% of flowered plants) began 47 days after the first flower bud initiation with no statistical differences among the treatments. Plants treated with TDZ 500–1000 mg L−1 showed the longest period of flowering (about 32 days) and the single flowers delayed the withering of about 2–3 days compared to the lowest TDZ treatment (200 mg L−1). The number of flowers, floral branches and flowering percentage were distinctly influenced by the TDZ concentration. The highest percentage of flowering (40%) was scored when plants were watered with a TDZ solution at 500 mg L−1 and this was a performant treatment providing the best morphological flower features for the ornamental value of this plant. Among the physiological factors affecting the flowering, this study showed that TDZ increased the relative membrane permeability which facilitated the transport of macromolecular flower-forming substances into and out of the membrane. Therefore, the membrane permeability change could be an indicator of shifts in physiologically active substances during the flowering transition process in Dendrobium nobile plants.

The objective of this work was to analyze the effect of Thidiazuron (TDZ) treatment on floral initiation, flowering time, ornamental characteristics and physiological metabolism of potted Dendrobium nobile. Three TDZ concentrations (200, 500 and 1000 mg L[sup.−1] ) were applied as solution to water the root zone of the plants. Control plants (plants watered with water) showed a good vegetative development but no floral branches. TDZ greatly influenced the flowering process. For all the tested TDZ concentrations, the first flower bud occurred at 55–60 days after the last irrigation (DAI), the highest TDZ concentration showing the major delay in its occurrence. The initial flowering (30% of flowered plants) began 47 days after the first flower bud initiation with no statistical differences among the treatments. Plants treated with TDZ 500–1000 mg L[sup.−1] showed the longest period of flowering (about 32 days) and the single flowers delayed the withering of about 2–3 days compared to the lowest TDZ treatment (200 mg L[sup.−1] ). The number of flowers, floral branches and flowering percentage were distinctly influenced by the TDZ concentration. The highest percentage of flowering (40%) was scored when plants were watered with a TDZ solution at 500 mg L[sup.−1] and this was a performant treatment providing the best morphological flower features for the ornamental value of this plant. Among the physiological factors affecting the flowering, this study showed that TDZ increased the relative membrane permeability which facilitated the transport of macromolecular flower-forming substances into and out of the membrane. Therefore, the membrane permeability change could be an indicator of shifts in physiologically active substances during the flowering transition process in Dendrobium nobile plants.

DNA/RNA-gold nanoparticle (DNA/RNA-AuNP) nanoprobes have been widely employed for nanobiotechnology applications. Here we discovered that both thiolated and non-thiolated DNA/RNA can be efficiently attached to AuNPs to achieve high-stable spherical nucleic acid (SNA) within minutes under a domestic microwave (MW)-assisted heating-dry circumstance. Further studies showed that for non-thiolated DNA/RNA the conjugation is poly (T/U) tag dependent. Spectroscopy, test strip hybridization, and loading counting experiments indicate that low-affinity poly (T/U) tag mediates the formation of a standing-up conformation, which is distributed in the outer layer of such a SNA structure. In further applications study, CRISPR/Cas9-sgRNA (135 bp), RNA from Nucleocapsid (N) gene of SARS-CoV-2 (1279 bp), and rolling circle amplification (RCA) DNA products (over 1000 bp) could be successfully attached on AuNPs, which overcomes the routine methods in long-chain nucleic acid-AuNP conjugation, exhibiting great promise in novel biosensing and nucleic acids delivery strategy. This novel heating-dry strategy has improved the traditional DNA/RNA-AuNP conjugation methods in simplicity, rapidity, cost, and universality. Competing Interest Statement The authors have declared no competing interest.

We aimed to construct a validated nomogram model for predicting short-term (28-day) ischemic stroke mortality among critically ill populations. We collected raw data from the Medical Information Mart for Intensive Care IV database, a comprehensive repository renowned for its depth and breadth in critical care information. Subsequently, a rigorous analytical framework was employed, incorporating a 10-fold cross-validation procedure to ensure robustness and reliability. Leveraging advanced statistical methodologies, specifically the least absolute shrinkage and selection operator regression, variables pertinent to 28-day mortality in ischemic stroke were meticulously screened. Next, binary logistic regression was utilized to establish nomogram, then applied concordance index to evaluate discrimination of the prediction models. Predictive performance of the nomogram was assessed by integrated discrimination improvement (IDI) and net reclassification index (NRI). Additionally, we generated calibration curves to assess calibrating ability. Finally, we evaluated the nomogram's net clinical benefit using decision curve analysis (DCA), in comparison with scoring systems clinically applied under common conditions. A total of 2089 individuals were identified and assigned into training (n = 1443) or validation (n = 646) cohorts. Various identified risk factors, including age, ethnicity, marital status, underlying metastatic solid tumor, Charlson comorbidity index, heart rate, Glasgow coma scale, glucose concentrations, white blood cells, sodium concentrations, potassium concentrations, mechanical ventilation, use of heparin and mannitol, were associated with short-term (28-day) mortality in ischemic stroke individuals. A concordance index of 0.834 was obtained in the training dataset, indicating that our nomogram had good discriminating ability. Results of IDI and NRI in both cohorts proved that our nomogram had positive improvement of predictive performance, compared to other scoring systems. The actual and predicted incidence of mortality showed favorable concordance on calibration curves (P > 0.05). DCA curves revealed that, compared with scoring systems clinically used under common conditions, the constructed nomogram yielded a greater net clinical benefit. Utilizing a comprehensive array of fourteen readily accessible variables, a prognostic nomogram was meticulously formulated and rigorously validated to provide precise prognostication of short-term mortality within the ischemic stroke cohort.