Topological effect of an intramolecular split G-quadruplex on thioflavin T binding and fluorescence light-up.

In this work, the topological effect on binding interaction between a G-quadruplex and thioflavin T (ThT) ligand was systematically investigated on a platform of an intramolecular split G-quadruplex (Intra-SG). Distinct fluorescence changes from ThT were presented in the presence of distinct split modes of Intra-SG structures and an intriguing phenomenon of target-induced fluorescence light-up occurred for split modes 2 : 10, 5 : 7 and 8 : 4. It was validated that hybridization between the Intra-SG spacer and target did not unfold the G-quadruplex, but facilitated the ThT binding. Moreover, the 3' guanine-rich fragment of Intra-SG was very susceptible to topology variation produced by the bound target strand. Additionally, a bioanalytical method was developed for ultrasensitive gene detection, confirming the utility of the ThT/Intra-SG complex as a universal signal transducer. It is believed that the results and disclosed rules will inspire researchers to develop many new DNA-based signal transducers in the future.

Attenuated Salmonella-delivered PD-1 siRNA enhances the antitumor effects of EZH2 inhibitors in colorectal cancer.

Immunotherapy has made significant progress in the treatment of malignant tumors. However, strategies to combine immunotherapy with anticancer drugs have attracted great attention due to the low response rate and unique toxicity profile of immunotherapies and the subsequent development of acquired resistance in some initial responders. EZH2, a histone methyl transferase subunit of a Polycomb repressor complex,is highly expressed in a variety of tumors, and targeting EZH2 has become a new strategy for tumor therapy and drug combination. Here，we studied the effect of EZH2 inhibitors on colorectal cancer cells and their combination with immunotherapy. Our results demonstrated that EZH2 inhibitors can not only significantly inhibit the survival of colorectal cancer (CRC) cells and induce apoptosis, effectively inhibit cell invasion and migration, but also cause an increase in the expression of PD-L1 receptors on the cell surface. To determine the effect of EZH2 in combination with immunotherapy, we combine EZH2 inhibitors with PD-1 siRNA delivered by attenuated Salmonella. The vivo experiments have shown that the combination of EZH2 inhibitors and Salmonella-delivered PD-1 siRNA can further inhibit the development of CRC, trigger effective anti-tumor immunity, and improve therapeutic efficacy. Its underlying mechanisms mainly involve synergistic immunomodulation and apoptosis. This study suggests an emerging strategy based on a combination of EZH2 inhibitor and immunotherapy based on PD-1 inhibition.

Workplace violence and burnout among Chinese nurses during the COVID-19 pandemic: does the sense of coherence mediate the relationship?

BACKGROUND: Workplace violence has always been a critical issue worldwide before and after the COVID-19 pandemic, which can lead to burnout and turnover. In addition, the burnout and mental stress of nurses during the COVID-19 period have been widely described. To our knowledge, no studies have examined the mediating effect of the sense of coherence on the relationship between workplace violence and burnout among Chinese nurses over time. Therefore, this study aimed to explore the relationship between workplace violence and burnout among Chinese nurses and how the sense of coherence mediates the association. METHODS: Using a convenience sampling method, 1190 nurses from 4 tertiary grade-A comprehensive hospitals were investigated between September 2021 and December 2021 in 3 provinces of China. The Workplace Violence Scale, Burnout Inventory, and Sense of Coherence scale were used to collect data. Data analysis was conducted using descriptive statistics, Pearson correlation, and regression analysis to estimate direct and indirect effects using bootstrap analysis. RESULTS: The mean total scores for workplace violence and burnout were 1.67 ± 1.08 and 47.36 ± 18.39, respectively. Workplace violence was significantly negatively correlated with the sense of coherence (r = -0.25) and positively correlated with burnout (r = 0.27). Additionally, a higher level of workplace violence was associated with higher burnout (ß = 1.13, 95% CI: 0.68 ~ 1.56). A higher sense of coherence was also associated with lower burnout (ß = -0.98, 95% CI: -1.03 ~ -0.92). Workplace violence showed an effect on burnout through a sense of coherence. The direct, indirect and total effects were 1.13, 1.88 and 3.01, respectively. The mediating effect of the sense of coherence accounted for 62.45% of the relationship between workplace violence and burnout. CONCLUSION: We found that the sense of coherence mediated most workplace violence on burnout. It is imperative for hospital managers to improve nurses' sense of coherence to reduce the occurrence of burnout during COVID-19. Future intervention studies should be designed to strengthen nurses' sense of coherence.

MACC1 as a Potential Target for the Treatment and Prevention of Breast Cancer.

Metastasis associated in colon cancer 1 (MACC1) is an oncogene first identified in colon cancer. MACC1 has been identified in more than 20 different types of solid cancers. It is a key prognostic biomarker in clinical practice and is involved in recurrence, metastasis, and survival in many types of human cancers. MACC1 is significantly associated with the primary tumor, lymph node metastasis, distant metastasis classification, and clinical staging in patients with breast cancer (BC), and MACC1 overexpression is associated with reduced recurrence-free survival (RFS) and worse overall survival (OS) in patients. In addition, MACC1 is involved in BC progression in multiple ways. MACC1 promotes the immune escape of BC cells by affecting the infiltration of immune cells in the tumor microenvironment. Since the FGD5AS1/miR-497/MACC1 axis inhibits the apoptotic pathway in radiation-resistant BC tissues and cell lines, the MACC1 gene may play an important role in BC resistance to radiation. Since MACC1 is involved in numerous biological processes inside and outside BC cells, it is a key player in the tumor microenvironment. Focusing on MACC1, this article briefly discusses its biological effects, emphasizes its molecular mechanisms and pathways of action, and describes its use in the treatment and prevention of breast cancer.

Proximity ligation-transcription circuit-powered exponential amplifications for single-molecule monitoring of telomerase in human cells.

We develop a new strategy for single-molecule monitoring of telomerase based on proximity ligation-transcription circuit-powered exponential amplifications. This strategy exhibits high sensitivity with a detection limit of 0.1 aM for the synthetic telomerase product TPC4 in vitro and 1 HeLa cell in vivo. Moreover, it can screen potential inhibitors, discriminate telomerase from interferents, and distinguish cancer cells from normal cells.

Facile one-step synthesis of NIR-Responsive siRNA-Inorganic hybrid nanoplatform for imaging-guided photothermal and gene synergistic therapy.

Diagnosis-guided synergistic treatment based on innovative nanomaterials is of great significance for the development of anti-cancer therapies. However, the low delivery efficiency of therapeutic gene and the inability to trigger release on demand are still major obstacles impeding its wide application. Herein, we report an ultra-fast one-step method within 2 min to prepare a smart carrier, liposome-coated Prussian blue @ gold nano-flower, which is named LPAR after linking with tumor-targeting peptide. The versatile LPAR not only can respond to near-infrared (NIR) light, achieve the selective delivery and the controlled release of siRNA targeting the mutant gene of Kras at its codon-12 from Glycine (G) to Aspartic acid (D) (named as G12D mutant gene) in the malignant pancreatic tumors, but also efficiently convert the absorbed NIR light into the heat to realize gene-photothermal synergistic therapy both in vitro and in vivo. Theoretical simulation results reveal that the outstanding photothermal conversion efficiency of LPAR is mainly due to its higher electric field intensity and power density distributions. Furthermore, the LPAR possesses the capabilities for triple-modal imaging. Therefore, the developed NIR light-responsive LPAR has the potential to be served as a tumor-targeted nano-delivery system for imaging-guided synergistic therapy of cancers.

Dimeric G-Quadruplex: An Efficient Probe for Ultrasensitive Fluorescence Detection of Mustard Compounds.

Some mustard compounds (mustards) are highly toxic chemical warfare agents. Some are explored as new anticancer drugs. Therefore, the fast, selective, and sensitive detection of mustards is extremely important for public security and cancer therapy. Mustards mostly target the N7 position on the guanine bases of DNA. The guanine-rich G-quadruplex DNA (G4) has been widely studied in the sensing area, and it was found that dimeric G4 (D-G4) could dramatically light up the fluorescence intensity of thioflavin T (ThT). Based on this, we used for the first time the D-G4 DNA as a selective probe for ultrasensitive fluorescence detection of nitrogen mustard (NM). When NM occupies the N7 on guanine, it can block the formation of the D-G4 structure due to the steric hindrance, and hence, it inhibits the combination of D-G4 with ThT, leading to a sharp decrease of fluorescence intensity. The proposed reaction mechanism is proved using ultraviolet-visible (UV-Vis) spectra, circular dichroism (CD) spectra, and polyacrylamide gel electrophoresis. Herein, the concentration of D-G4/ThT used is as low as 50 nM due to its highly fluorescent performance, enabling both high sensitivity and low cost. NM can be detected with a wide linear range from 10 to 2000 nM. The detection limit of NM reaches a surprisingly low concentration of 6 nM, which is 2 or 3 orders of magnitude lower than that of previously developed fluorescence methods for mustards and simulants.

LncRNA MNX1-AS1 promotes ovarian cancer process via targeting the miR-744-5p/SOX12 axis.

PURPOSE: Ovarian cancer (OC) is the most common malignancy in women with high mortality. Increasing studies have revealed that long non-coding RNA (lncRNA) MNX1-AS1 has a promoting effect on various cancers. However, the mechanisms of MNX1-AS1 in OC are still unclear. Therefore, this study focused on exploring the mechanisms of MNX1-AS1 in OC. MATERIALS AND METHODS: The expression of SOX12 at the protein level was detected by western blot. Cell proliferation was detected by CCK8 assay and colony formation assay. Cell cycle and cell apoptosis were detected by flow cytometry. Wound-healing assay, transwell assay and western blot were used to detect the ability of cell migration and invasion. The target binding was confirmed through the luciferase reporter assay. RESULTS: The expression of MNX1-AS1 was increased in OC tumor tissues and cells. Elevated MNX1-AS1 expression is associated with advanced stage and lower overall survival rate. Knockdown of MNX1-AS1 inhibited cell proliferation, migration and invasion, blocked cell cycle, and promoted cell apoptosis in SKOV-3 and OVCAR-3 cells. MNX1-AS1 was competitively binding with miR-744-5p, and its downstream target gene was SOX12. miR-544-5p expression was decreased, while SOX12 expression was increased in OC tumor tissues and cells. Overexpression of miR-744-5p inhibited cell proliferation, migration, invasion and promoted cell apoptosis in SKOV-3 and OVCAR-3 cells. CONCLUSION: MNX1-AS1 promoted the development of OC through miR-744-5p/SOX12 axis. This study revealed a novel mechanism of MNX1-AS1 in OC, which may provide a new treatment or scanning target for OC.

Correlation analysis of Ki67 and CK7 expression with clinical characteristics and prognosis of postoperative cervical adenocarcinoma patients.

BACKGROUND: The purpose of this study is to investigate the correlation between cytokeratin 7 (CK7) and marker of proliferation Ki67 protein expression and clinical characteristics and prognosis of patients with cervical adenocarcinoma after surgery. METHODS: A total of 126 patients with cervical adenocarcinoma treated by surgery in our hospital from June 2011 to September 2015 were enrolled in this study. Immunohistochemistry (IHC) was used to detect the expression of CK7 and Ki67 in 126 cases of cervical adenocarcinoma tissues. The chi-square (χ2) test was used to compare the relationship between the positive expression rate of CK7 or Ki67 and clinicopathological features. Kaplan-Meier method was used to analyze the survival of different protein expression groups and Cox proportional hazards regression model was used to analyze the risk factors affecting the prognosis. RESULTS: The positive rate of CK7 was correlated with muscle invasion, vascular invasion, differentiation, and lymph node metastasis (all P<0.05). The positive expression rate of Ki67 was related to the degree of myometrial invasion and International Federation of Gynecology and Obstetrics (FIGO) stage (both P<0.05). Both CK7 and Ki67 may be independent risk factors for the prognosis of patients with cervical adenocarcinoma after surgery (both P<0.05), and their high expression heralds worse prognosis. CONCLUSIONS: The CK7 and Ki67 proteins may be key regulatory factors in the development of cervical adenocarcinoma after surgery, and their overexpression may lead to worse prognosis. Both CK7 and Ki67 may provide new markers for prognosis evaluation of cervical adenocarcinoma.

In Situ Fluorogenic Reaction Generated via Ascorbic Acid for the Construction of Universal Sensing Platform.

A highly fluorescent emission reaction between terephthalic acid (PTA) and ascorbic acid (AA) via simple control of the reaction temperature was first revealed with the detailed formation mechanism and various characterizations including electron paramagnetic resonance and mass spectrometry. Based on the AA-responsive emission, the alkaline phosphatase (ALP) triggered the transformation of l-ascorbic acid 2-phosphate trisodium salt to AA was integrated with the present system for developing a sensitive, selective, and universal platform. The monitoring of the activity of ALP and the fabrication of ALP-based enzyme-linked immunoassay (ELISA) with carcinoembryonic antigen (CEA) as the model target was performed. The fluorescence intensity correlated well to the CEA concentration in the ranges of 0.25-30 ng/mL, with a detection limit of 0.08 ng/mL. Such a facile protocol based on the fluorescent reaction between PTA and AA without the assistance of catalysis of nanomaterials avoided the laborious synthesis procedure and provided a direct strategy for the early clinical diagnosis coupled with ALP-related catalysis.

MicroRNA-370-3p shuttled by breast cancer cell-derived extracellular vesicles induces fibroblast activation through the CYLD/Nf-κB axis to promote breast cancer progression.

Breast cancer is a malignancy arising in the mammary epithelial tissues. Recent studies have indicated the abundance of microRNAs (miRNAs) in extracellular vesicles (EVs), and their interactions have been illustrated to exert crucial roles in the cell-to-cell communication. The present study focused on investigating whether EV-delivered miR-370-3p affects breast cancer. Initially, the miR-370-3p expression pattern was examined in the cancer-associated fibroblasts (CAFs), normal fibroblasts (NFs), and cancerous cells-derived EVs. The relation of miR-370-3p to CYLD was assessed using luciferase activity assay. Afterwards, based on ectopic expression and depletion experiments in the MCF-7 breast cancer cells, we evaluated stemness, migration, invasion, and sphere formation ability, and EMT, accompanied with measurement on the expression patterns of pro-inflammatory factors and nuclear factor-kappa B (NF-κB) signaling-related genes. Finally, tumorigenesis and proliferation were analyzed in vivo using a nude mouse xenograft model. The in vitro experiments revealed that breast cancer cell-derived EVs promoted NF activation, while activated fibroblasts contributed to enhanced stemness, migration, invasion, as well as EMT of cancerous cells. In addition, EVs could transfer miR-370-3p from breast cancer cells to NFs, and EV-encapsulated miR-370-3p was also found to facilitate fibroblast activation. Mechanistically, EV-encapsulated miR-370-3p downregulated the expression of CYLD through binding to its 3'UTR and activated the NF-κB signaling pathway, thereby promoting the cellular functions in vitro and in vivo in breast cancer. Taken together, EVs secreted by breast cancer cells could carry miR-370-3p to aggravate breast cancer through downregulating CYLD expression and activating the NF-κB signaling pathway.

Regulating Catalytic Activity of DNA-Templated Silver Nanoclusters Based on their Differential Interactions with DNA Structures and Stimuli-Responsive Structural Transition.

This work reports exquisite engineering of catalytic activity of DNA-templated silver nanoclusters (DNA-AgNCs) based on unique adsorption phenomena of DNAs on DNA-AgNCs and reversible transition between double and triple-stranded DNAs. Four DNA homopolymers exhibit different inhibition effects on the catalytic activity of DNA-AgNCs, poly adenine (polyA) > poly guanine (polyG) > poly cytosine (polyC) > poly thymine (polyT), demonstrating that polyA strands have the strongest adsorption affinity on DNA-AgNCs. Through the formation of T-A•T triplex DNAs, catalytic activity of DNA-AgNCs is restored from the deactivated state by double or single-stranded DNAs, indicating the participation of N7 groups of adenine bases in binding to DNA-AgNCs and blocking active sites. Accordingly, reversibly regulating catalytic activity of DNA-AgNCs can be realized based on DNA input-stimulated transition between duplex and triplex structures. In the end, two low-cost and facile biosensing methods are presented, which are derived from the activity-switchable platform. It is worthy to anticipate that the DNA-AgNCs with controlled catalytic activity will inspire researchers to devise more functionalized nanocatalysts and contribute to the exploration of intelligent biomedicine in the future.

Effect of Rho GTPase activating protein 9 combined with preoperative ratio of platelet distribution width to platelet count on prognosis of patients with serous ovarian cancer.

BACKGROUND: This study aimed to investigate the relationship between Rho GTPase activating protein 9 (ARHGAP9) combined with preoperative ratio of platelet distribution width to platelet count (PDW/PLT) and patients prognosis with serous ovarian cancer. METHODS: The clinical data of 80 patients with serous ovarian cancer treated in Jiangsu Cancer Hospital from May 2011 to May 2016 were analyzed retrospectively. We verified ARHGAP9 expression in The Cancer Genome Atlas (TCGA) database, then detected messenger RNA (mRNA) expression encoding ARHGAP9 in ovarian cancer tissue samples using reverse transcription quantitative polymerase chain reaction (RT-qPCR). These patients were divided into an ARHGAP9 low-expression group and an ARHGAP9 high-expression group. The optimal critical value of PDW/PLT was determined by receiver operating characteristic (ROC) curve. The patients were divided into low PDW/PLT group and high PDW/PLT group. Kaplan-Meier method and log-rank test were used for univariate survival analysis, Cox regression method was used for multivariate analysis, and then a nomogram was constructed for internal verification. RESULTS: The ARHGAP9 protein was highly expressed both in TCGA serous ovarian cancer database and the serous ovarian cancer tumor tissues. There were significant differences in menstrual status, the International Federation of Gynecology and Obstetrics (FIGO) stage and grade between the ARHGAP9 low expression group and ARHGAP9 high expression group (all P<0.05). There were significant differences in FIGO stage, lymph node metastasis, and ascites between the low PDW/PLT group and high PDW/PLT group (all P<0.05). Finally, 80 patients were included, with a mortality rate of 45.0% and a survival rate of 55.0%; the median progression-free survival (PFS) was 19 months, and the median overall survival (OS) was 62.5 months. Cox multivariate analysis showed that PDW/PLT and ARHGAP9 were independent risk factors for tumor progression (P=0.026 and P=0.028, respectively). In the internal validation, the C-index of the nomogram was 0.6518 [95% confidence interval (CI): 0.5685 to 0.7352], and the prediction model had certain accuracy. CONCLUSIONS: ARHGAP9 and PDW/PLT Decrease can significantly prolong OS and PFS in serous ovarian cancer patients. Therefore, ARHGAP9 can be used as a new predictive biomarker and may be related to the immune infiltration of serous ovarian cancer.

LINC00641 inhibits the proliferation and invasion of ovarian cancer cells by targeting miR-320a.

BACKGROUND: Ovarian cancer is a common malignancy of the female reproductive system, with one of the highest mortality rates among all malignant tumors. However, the pathogenesis of ovarian cancer has not been fully elucidated. This study investigated the role and molecular mechanism of LINC00641 in the development and progression of ovarian cancer. METHODS: Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the expression level of LINC00641 in ovarian cancer tissue and adjacent normal tissue. Cell Counting Kit-8 (CCK-8), colony formation, and Transwell assays were used to detect the effects of LINC00641 overexpression on the proliferation and migration of ovarian cancer cells. Bioinformatics analysis and luciferase reporter gene assay were employed to detect the binding of LINC00641 to the downstream target molecule, microRNA-320a (miR-320a). Western blotting was used to determine the effect of miR-320a overexpression on the expression of proliferation-related proteins [Ki-67 and proliferating cell nuclear antigen (PCNA)] and invasion-related proteins (E-cadherin, N-cadherin, and vimentin) in overexpressed LINC00641 cells. RESULTS: qRT-PCR results showed that LINC00641 was under-expressed in ovarian cancer tissue compared to adjacent tissue. Cell function experiments showed that the overexpression of LINC00641 could significantly inhibit the proliferation and migration of ovarian cancer cells. The luciferase reporter gene assay showed that LINC00641 could bind to miR-320a, and the overexpression of LINC00641 could markedly inhibit the expression of miR-320a in ovarian cancer cells. Overexpression of miR-320a could significantly block the inhibitory effect of LINC00641 on the proliferation and migration of ovarian cancer cells. CONCLUSIONS: As a tumor suppressor gene, LINC00641 can inhibit the proliferation and invasion of ovarian cancer cells by targeting miR-320a. The LINC00641/miR-320a axis may be a new target for the early diagnosis, treatment, or prognosis of ovarian cancer patients.

The Mediating Role of Resilience and Self-Esteem Between Life Events and Coping Styles Among Rural Left-Behind Adolescents in China: A Cross-Sectional Study.

Objective: This study aims to explore the association between life events and coping styles, and how resilience and self-esteem mediate the association. Methods: A cross-sectional study was conducted among 981 left-behind adolescents (LBAs) in five junior high schools in Hunan Province, China, from April 13 to April 20, 2020. We utilized self-designed sociodemographic questionnaire, Adolescent Self-Rating Life Events Checklist, Resilience Scale Chinese Adolescent, Rosenberg Self-Esteem Scale, and Simplified Coping Style Questionnaire to assess the mental health of LBAs. Statistic description, Pearson correlation analysis, and structural equation model were adopted to analyze the data. Results: Results revealed that life events could negatively predict resilience (ß = -0.29, P < 0.001) and self-esteem (ß = -0.39, P < 0.001) and positively predict LBAs' positive coping style (ß = 0.28, P < 0.001) and negative coping style (ß = 0.21, P < 0.001). Self-esteem could also positively predict the resilience of LBAs (ß = 0.62, P < 0.001); resilience could negatively predict the negative coping style (ß = -0.21, P < 0.001) and positively predict the positive coping style (ß = 0.79, P < 0.001). Life events not only have direct effects on negative coping style (ß = 0.21) and positive coping style (ß = 0.28) but also have indirect effects on coping styles by affecting resilience (ß = -0.29) and self-esteem (ß = -0.39). The total effect of life events on coping styles was 0.32, where 34.37% was mediated by resilience and self-esteem. Conclusion: We proved that resilience and self-esteem mediated most of the effects of life events on coping styles. The findings had important implications for interventions to promote mental health of LBAs, particularly the enhancement of resilience and self-esteem.

Burnout and associated occupational stresses among Chinese nurses: A cross-sectional study in three hospitals.

BACKGROUND: There is literature scarcity relating to burnout and other work stresses in relation to Chinese nursing-workforce performance. OBJECTIVES: To assess the relationship between self-esteem versus burnout; and effort-reward ratio versus favorability to the work environment, among Chinese nurses. METHODS: We employed four validated questionnaires in the assessment burnout, self-esteem, effort-reward ratio, and favorability of nursing workplace; Maslach-Burnout Inventory (MBI), Rosenberg's self-esteem (RS), Effort-Reward imbalance (ERI) and Work-Environment Scale questionnaires (WES). Linear and ordinal regression models were utilized to assess the relationships between the variables. Analyses were conducted by using SPSS at a 95% level of significance. RESULTS: We assessed 487 (Mean age: 38.8±7.1 years) nurses from three hospitals. Higher self-esteem was associated with a lower level of emotional exhaustion (Unstandardized coefficient: -0.579, p-Value<0.001); and a lower level of depersonalization (Unstandardized coefficient: -0.212, p-Value = 0.001). The relationship between self-esteem and personal achievement did not reach statistical significance. A higher effort-reward ratio was associated with less likelihood that nurses would consider their work environment favorable (Logit estimate of -0.832, p-Value = 0.014). CONCLUSION: Lower self-esteem is associated with increased burnout. A higher effort-reward ratio is associated with an enhanced perception work environment as unfavorable. We recommend psychosocial intervention programs and amendments in nursing policies to improve effort-reward imbalance among Chinese nurses.

High Quality Pyrazinoquinoxaline-Based Graphdiyne for Efficient Gradient Storage of Lithium Ions.

N-doping of graphdiyne with atomic precision is very important for the study of heteroatom doping effect and the structure-properties relationships of graphdiyne. Here we report the bottom-up synthesis and characterizations of high-quality pyrazinoquinoxaline-based graphdiyne (PQ-GDY) film. First-principle studies of the layered structure were performed to examine the stacking mode, lithium binding affinity, and bulk lithium storage capacity. Three-stage insertion of 14 lithium atoms with binding affinities in the order of pyrazine nitrogen > diyne carbon > central aromatic ring were confirmed by both lithium-ion half-cell measurements and DFT calculations. More than half of the lithium atoms preferentially bind to pyrazine nitrogen, and a reversible capacity of 570.0 mA h g-1 at a current density of 200 mA g-1 after 800 cycles was achieved. Such a high capacity utilization rate of 97.2% provides a good case study of N-doped GDY with atomic precision.

Illuminating Diverse Concomitant DNA Logic Gates and Concatenated Circuits with Hairpin DNA-Templated Silver Nanoclusters as Universal Dual-Output Generators.

Exquisite administration of a new type of hairpin DNA-templated silver nanoclusters (H-AgNCs) as universal dual-output generators in DNA-based logic systems is reported. Diverse concomitant contrary logic gates (CCLGs) with opposite functions (YES^ NOT, OR^ NOR, INHIBIT^ IMPLICATION, XOR^ XNOR, and MAJORITY^ MINORITY) and extended concatenated logic circuits are presented and some of them perform specific functions, such as parity generators and checkers. The introduction of H-AgNCs as noncovalent signal reporters avoids tedious and high-cost labeling procedures. Of note, the concomitant feature of CCLGs attributed to the dual-emitter AgNCs conduces to reducing the time and cost to devise multiple logic gates. As compared to previous ones, this design eliminates numerous substances (e.g., organic dyes) and unstable components (hydrogen peroxide), which not only decreases the complexity of logic performs and improves repeatability of operation, but also makes it convenient to connect distinct DNA-based logic gates. It is worthy to anticipate that the cost-effective strategy will inspire researchers to develop much more complex logic systems and contribute to the field of molecular computing.

Exploration of intramolecular split G-quadruplex and its analytical applications.

Distinct from intermolecular split G-quadruplex (Inter-SG), intramolecular split G-quadruplex (Intra-SG) which could be generated in a DNA spacer-inserted G-quadruplex strand has not been systematically explored. Not only is it essential for the purpose of simplicity of DNA-based bioanalytical applications, but also it will give us hints how to design split G-quadruplex-based system. Herein, comprehensive information is provided about influences of spacer length and split mode on the formation of Intra-SG, how to adjust its thermodynamic stability, and selection of optimal Intra-SG for bioanalysis. For instances, non-classical Intra-SG (e.g. 2:10, 4:8 and 5:7) displays lower stability than classical split strands (3:9, 6:6 and 9:3), which is closely related to integrity of consecutive guanine tract; as compared to regular Intra-SG structures, single-thymine capped ones have reduced melting temperature, providing an effective approach to adjustment of stability. It is believed that the disclosed rules in this study will contribute to the effective application of split G-quadruplex in the field of DNA technology in the future.

Identification of internal control genes for circular RNAs.

OBJECTIVE: At present, no studies have established internal control genes for circular RNA (circRNA) analyses. We aimed to identify reference circRNAs for real-time quantitative PCR (RT-qPCR). RESULTS: After analyzing the RNA-seq data, we obtained 50 circRNAs that were expressed in all samples. We ranked these 50 circRNAs according to their stability and obtained the six most stable circRNAs. We further evaluated the stability of the six circRNAs and three linear control genes (i.e., GAPDH, ß-actin and 18S rRNA) in 22 cell lines. Our results indicated that hsa_circ_0000284 (circHIPK3) and hsa_circ_0000471 (circN4BP2L2) were the two most stable genes. After removing linear RNAs or including the cells treated with Adriamycin, NH4Cl and shikonin, the two most stable genes were hsa_circ_0000471 and hsa_circ_0000284. The amplification efficiency was 100% for hsa_circ_0000471 and 95% for hsa_circ_0000284. CONCLUSIONS: In conclusion, since the stability of circRNAs is higher than that of linear RNAs, hsa_circ_0000284 and hsa_circ_0000471 may be used as reference genes not only for circRNAs but also for other kinds of RNAs. The findings in the present study fill the gap of lacking reference genes in the detection of circRNAs.