Accurate Cancer Screening and Prediction of PD-L1-Guided Immunotherapy Efficacy Using Quantum Dot Nanosphere Self-Assembly and Machine Learning.

Accurate quantification of exosomal PD-L1 protein in tumors is closely linked to the response to immunotherapy, but robust methods to achieve high-precision quantitative detection of PD-L1 expression on the surface of circulating exosomes are still lacking. In this work, we developed a signal amplification approach based on aptamer recognition and DNA scaffold hybridization-triggered assembly of quantum dot nanospheres, which enables bicolor phenotyping of exosomes to accurately screen for cancers and predict PD-L1-guided immunotherapeutic effects through machine learning. Through DNA-mediated assembly, we utilized two aptamers for simultaneous ultrasensitive detection of exosomal antigens, which have synergistic roles in tumor diagnosis and treatment prediction, and thus, we achieved better sample classification and prediction through machine-learning algorithms. With a drop of blood, we can distinguish between different cancer patients and healthy individuals and predict the outcome of immunotherapy. This approach provides valuable insights into the development of personalized diagnostics and precision medicine.

Advances in rapid point-of-care virus testing.

Outbreaks of viral diseases seriously jeopardize people's health and cause huge economic losses. At the same time, virology provides a new perspective for biology, molecular biology and cancer research, and it is important to study the discovered viruses with potential applications. Therefore, the development of immediate and rapid viral detection methods for the prevention and treatment of viral diseases as well as the study of viruses has attracted extensive attention from scientists. With the continuous progress of science and technology, especially in the field of bioanalysis, a series of new detection techniques have been applied to the on-site rapid detection of viruses, which has become a powerful approach for human beings to fight against viruses. In this paper, the latest research progress of rapid point-of-care detection of viral nucleic acids, antigens and antibodies is presented. In addition, the advantages and disadvantages of these technologies are discussed from the perspective of practical application requirements. Finally, the problems and challenges faced by rapid viral detection methods and their development prospects are discussed.

Real-Time Imaging of Single Viral mRNA Translation in Live Cells Using CRISPR/dCas13.

Translation is one of the many critical cellular activities regulated by viruses following host-cell invasion, and studies of viral mRNA translation kinetics and subcellular localization require techniques for the dynamic, real-time visualization of translation. However, conventional tools for imaging mRNA translation often require coding region modifications that may affect native translation. Here, we achieve dynamic imaging of translation with a tool that labels target mRNAs with unmodified coding regions using a CRISPR/dCas13 system with specific complementary paired guide RNAs. This system enables a real-time dynamic visualization of the translation process and is a promising tool for further investigations of the mechanisms of translation.

High-resolution magnetic resonance imaging-based radiomic features aid in selecting endovascular candidates among patients with cerebral venous sinus thrombosis.

OBJECTIVES: Cerebral venous sinus thrombosis (CVST) can cause sinus obstruction and stenosis, with potentially fatal consequences. High-resolution magnetic resonance imaging (HRMRI) can diagnose CVST qualitatively, although quantitative screening methods are lacking for patients refractory to anticoagulation therapy and who may benefit from endovascular treatment (EVT). Thus, in this study, we used radiomic features (RFs) extracted from HRMRI to build machine learning models to predict response to drug therapy and determine the appropriateness of EVT. MATERIALS AND METHODS: RFs were extracted from three-dimensional T1-weighted motion-sensitized driven equilibrium (MSDE), T2-weighted MSDE, T1-contrast, and T1-contrast MSDE sequences to build radiomic signatures and support vector machine (SVM) models for predicting the efficacy of standard drug therapy and the necessity of EVT. RESULTS: We retrospectively included 53 patients with CVST in a prospective cohort study, among whom 14 underwent EVT after standard drug therapy failed. Thirteen RFs were selected to construct the RF signature and CVST-SVM models. In the validation dataset, the sensitivity, specificity, and area under the curve performance for the RF signature model were 0.833, 0.937, and 0.977, respectively. The radiomic score was correlated with days from symptom onset, history of dyslipidemia, smoking, fibrin degradation product, and D-dimer levels. The sensitivity, specificity, and area under the curve for the CVST-SVM model in the validation set were 0.917, 0.969, and 0.992, respectively. CONCLUSIONS: The CVST-SVM model trained with RFs extracted from HRMRI outperformed the RF signature model and could aid physicians in predicting patient responses to drug treatment and identifying those who may require EVT.

In Situ Self-Assembly of Fluorogenic RNA Nanozipper Enables Real-Time Imaging of Single Viral mRNA Translation.

Real-time visualization of individual viral mRNA translation activities in live cells is essential to obtain critical details of viral mRNA dynamics and to detect its transient responses to environmental stress. Fluorogenic RNA aptamers are powerful tools for real-time imaging of mRNA in live cells, but monitoring the translation activity of individual mRNAs remains a challenge due to their intrinsic photophysical properties. Here, we develop a genetically encoded turn-on 3,5-difluoro-4-hydroxybenzylidene imidazolinone (DFHBI)-binding RNA nanozipper with superior brightness and high photostability by in situ self-assembly of multiple nanozippers along single mRNAs. The nanozipper enables real-time imaging of the mobility and dynamic translation of individual viral mRNAs in live cells, providing information on the spatial dynamics and translational elongation rate of viral mRNAs.

[Bioinformatics Analysis on Key Genes and Immune Infiltration of Osteosarcoma].

Objective To screen the potential key genes of osteosarcoma by bioinformatics methods and analyze their immune infiltration patterns. Methods The gene expression profiles GSE16088 and GSE12865 associated with osteosarcoma were obtained from the Gene Expression Omnibus(GEO),and the differentially expressed genes(DEGs)related to osteosarcoma were screened by bioinformatics tools.Gene Ontology(GO)annotation,Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment,and analysis of immune cell infiltration were then carried out for the DEGs.The potential Hub genes of osteosarcoma were identified by protein-protein interaction network,and the expression of Hub genes in osteosarcoma and normal tissue samples was verified via the Cancer Genome Atlas(TCGA). Results A total of 108 DEGs were screened out.GO annotation and KEGG pathway enrichment revealed that the DEGs were mainly involved in integrin binding,extracellular matrix (ECM) structural components,ECM receptor interactions,and phosphatidylinositol 3-kinase/protein kinase B(PI3K/Akt)signaling pathway.Macrophages were the predominant infiltrating immune cells in osteosarcoma.Secreted phosphoprotein 1(SPP1),matrix metallopeptidase 2(MMP2),lysyl oxidase(LOX),collagen type V alpha(II)chain(COL5A2),and melanoma cell adhesion molecule(MCAM)presented differential expression between osteosarcoma and normal tissue samples(all P<0.05). Conclusions SPP1,MMP2,LOX,COL5A2,and MCAM are all up-regulated in osteosarcoma,which may serve as potential biomarkers of osteosarcoma.Macrophages are the key infiltrating immune cells in osteosarcoma,which may provide new perspectives for the treatment of osteosarcoma.

Accurate and Efficient Lipoprotein Detection Based on the HCR-DNAzyme Platform.

Cardiovascular disease is one of the main causes of death in the world, which is closely associated with dyslipidemia. Dyslipidaemia is usually manifested as a relatively higher level of low-density lipoprotein (LDL) and lower level of high-density lipoprotein (HDL). Thus, the quantitative detection of the LDL and HDL particles is of great importance to predict the risk of cardiovascular diseases. However, the traditional methods can only indirectly reflect the HDL/LDL particle concentrations by detecting the cholesterol or proteins in HDL/LDL particles and are always laborious and time-consuming. Thus, the accurate and efficient approach for the detection of intact HDL and LDL particles is still lacking so far. We developed an enzyme- and isolation-free method to measure the concentration of HDL and LDL based on DNAzyme and hybridization chain reaction (HCR)-based signal amplification. This method can be used to directly and accurately detect the concentration of "actual" HDL and LDL particles instead of the cholesterol in HDL and LDL, with limits of detection of 10 and 30 mg/dL, respectively, which also satisfied the lipoprotein analysis in clinical samples. Therefore, this HCR-DNAzyme platform has great potential in clinical applications and health management.

MicroRNA-375-3p enhances chemosensitivity to 5-fluorouracil by targeting thymidylate synthase in colorectal cancer.

Resistance to chemotherapy is a major challenge for the treatment of patients with colorectal cancer (CRC). Previous studies have found that microRNAs (miRNAs) play key roles in drug resistance; however, the role of miRNA-373-3p (miR-375-3p) in CRC remains unclear. The current study aimed to explore the potential function of miR-375-3p in 5-fluorouracil (5-FU) resistance. MicroRNA-375-3p was found to be widely downregulated in human CRC cell lines and tissues and to promote the sensitivity of CRC cells to 5-FU by inducing colon cancer cell apoptosis and cycle arrest and by inhibiting cell growth, migration, and invasion in vitro. Thymidylate synthase (TYMS) was found to be a direct target of miR-375-3p, and TYMS knockdown exerted similar effects as miR-375-3p overexpression on the CRC cellular response to 5-FU. Lipid-coated calcium carbonate nanoparticles (NPs) were designed to cotransport 5-FU and miR-375-3p into cells efficiently and rapidly and to release the drugs in a weakly acidic tumor microenvironment. The therapeutic effect of combined miR-375 + 5-FU/NPs was significantly higher than that of the individual treatments in mouse s.c. xenografts derived from HCT116 cells. Our results suggest that restoring miR-375-3p levels could be a future novel therapeutic strategy to enhance chemosensitivity to 5-FU.

Nonadditive Transport in Multi-Channel Single-Molecule Circuits.

As stated in the classic Kirchhoff's circuit laws, the total conductance of two parallel channels in an electronic circuit is the sum of the individual conductance. However, in molecular circuits, the quantum interference (QI) between the individual channels may lead to apparent invalidity of Kirchhoff's laws. Such an effect can be very significant in single-molecule circuits consisting of partially overlapped multiple transport channels. Herein, an investigation on how the molecular circuit conductance correlates to the individual channels is conducted in the presence of QI. It is found that the conductance of multi-channel circuit consisting of both constructive and destructive QI is significantly smaller than the addition of individual ones due to the interference between channels. In contrast, the circuit consisting of destructive QI channels exhibits an additive transport. These investigations provide a new cognition of transport mechanism and manipulation of transport in multi-channel molecular circuits.

Distinguishing Diketopyrrolopyrrole Isomers in Single-Molecule Junctions via Reversible Stimuli-Responsive Quantum Interference.

Distinguishing structural isomers at the single-molecule level remains a challenge. We report the single-molecule recognition of two diketopyrrolopyrrole containing isomers (SDPP and SPPO) employing the mechanically controllable break junction technique. The single-molecule conductances of the two isomers are indistinguishable under normal conditions. However, reversible protonation and deprotonation of the SPPO in molecular junction result in more than 1 order of magnitude conductance change, which dramatically enhances the conductance difference between the two isomers. Theoretical study reveals that the dramatic conductance switching is due to reversible quantum interference effect. It is suggested that combination of stimuli-response and quantum interference can be an efficient strategy to enhance isomer recognition and conductance switching in single-molecule junctions.

Terminal Deoxynucleotidyl Transferase and T7 Exonuclease-Aided Amplification Strategy for Ultrasensitive Detection of Uracil-DNA Glycosylase.

As one of the key initiators of the base excision repair process, uracil-DNA glycosylase (UDG) plays an important role in maintaining genomic integrity. It has been found that aberrant expression of UDG is associated with a variety of diseases. Thus, accurate and sensitive detection of UDG activity is of critical significance for biomedical research and early clinical diagnosis. Here, we developed a novel fluorescent sensing platform for UDG activity detection based on a terminal deoxynucleotidyl transferase (TdT) and T7 exonuclease (T7 Exo)-aided recycling amplification strategy. In this strategy, only two DNA oligonucleotides (DNA substrate containing one uracil base and Poly dT probe labeled with a fluorophore/quencher pair) are used. UDG catalyzes the removal of uracil base from the enclosed dumbbell-shape DNA substrate to give an apyrimidinic site, at which the substrate oligonucleotide is cleaved by endonuclease IV. The released 3'-end can be elongated by TdT to form a long deoxyadenine-rich (Poly dA) tail, which may be used as a recyclable template to initiate T7 Exo-mediated hybridization-digestion cycles of the Poly dT probe, giving a significantly enhanced fluorescence output. The proposed UDG-sensing strategy showed excellent selectivity and high sensitivity with a detection limit of 1.5 × 10-4 U/mL. The sensing platform was also demonstrated to work well for UDG inhibitor screening and inhibitory activity evaluation, thus holding great potential in UDG-related disease diagnosis and drug discovery. The proposed strategy can be easily used for the detection of other DNA repair-related enzymes by simply changing the recognition site in DNA substrate and might also be extended to the analysis of some DNA/RNA-processing enzymes, including restriction endonuclease, DNA methyltransferase, polynucleotide kinase, and so on.

Establishment of lysozyme gene RNA interference systemand its involvement in salinity tolerance in sea cucumber (Apostichopus japonicus).

The lysozyme gene was silenced using RNA interference (RNAi) to analyze the function of lysozyme in sea cucumber under salt stress. The interfering efficiency of four lysozyme RNAi oligos ranged from 0.55 to 0.70. From the four oligos, p-miR-L245 was used for further interfering experiments because it had the best silencing efficiency. Peristomial film injection of p-miR-L245 (10 µg) was used for further interfering experiments. The lowest gene expression, determined by RT-PCR assay, in muscle, coelomic fluid, and parapodium occurred 48 h after p-miR-L245 injection, while that of body wall and tube foot was 96 h and 24 h, respectively. Lysozyme activity in muscle and body wall was significantly lower than the controls. The lowest lysozyme activity in muscle, body wall and parapodium, was found at 48, 72, and 48 h, respectively, which was consistent with the transcription expression of lysozyme. The lowest point of lysozyme activity was at 96 h in coelomic fluid and tube foot, which was laid behind lysozyme expression in transcription level. The expression profile of the lysozyme transcription level and lysozyme activity in the body wall and tube foot increased at 12 h after p-miR-L245 injection before the interference effect appeared. NKA gene expression was expressed at a high level in the positive control (PC) and negative control (NC) groups at 12, 24, and 48 h, while NKA was expressed at low levels in the lysozyme RNAi injection group at 12 and 24 h. The level of NKA gene expression recovered to the level of the PC and NC group at 48, 72, and 96 h after the lysozyme RNAi injection. NKCC1 gene expression was high in the PC and NC groups at 96 h, while the NKCC1 was expressed at a low level 96 h after lysozyme RNAi injection. The results suggest that lysozyme decay involves NKA and NKCC1 gene expression under salinity 18 psµ. The K+ and Cl- concentration after lysozyme RNAi injection was lower than in the PC and NC group.

Immune checkpoint inhibitor for different age patients with NSCLC in efficacy: A systematic review and meta-analysis.

OBJECTIVE: This article is a Meta-analysis aiming to systematically evaluate the difference in efficacy of immune checkpoint inhibitor in patients with non-small cell lung cancer (NSCLC) by age. METHODS: We performed a Meta-analysis of published randomized controlled trials concerning for patients with NSCLC by age. We compared overall survival among three groups (age <65 years, age 65-75 years, age ≥75 years). Hazard ratios (HRs) and 95% confidence intervals (CIs) were collected and pooled. RESULTS: A total of 10,291 patients from 17 RCTs were included. In the group under age 65 years, immune checkpoint inhibitor can significantly prolong the overall survival of patients with NSCLC (HR = 0.73, 95% CI: 0.66∼0.81, P < 0.00001). In the age 65-75 years group, immune checkpoint inhibitors prolonged overall survival in patients with NSCLC (HR = 0.78, 95% CI:0.71∼0.84, P < 0.00001). However, it has no significant effect on the overall survival of NSCLC patients (HR = 0.88, 95% CI:0.72∼1.08, P > 0.05) in the group older than 75 years. CONCLUSIONS: Immune checkpoint inhibitors prolonged the overall survival of NSCLC patients in the age <65 years group and the age 65-75 years group, but in the age ≥75 years group, there was no significant effect on overall survival. This may be related to innate immune and adaptive immune dysregulation due to "immunosenescence" in older patients.

Schiff base functionalized dialdehyde starch for enhanced removal of Cu (II): Preparation, performances, DFT calculations.

Dialdehyde starch modified by 2-hydrazinopyridine (HYD-DAS) based on the reaction of dialdehyde starch (DAS) and 2-hydrazinopyridine was synthesized and characterized by FT-IR spectra, element analysis and SEM. HYD-DAS can efficiently adsorb Cu (II) ion to demonstrate visual color changes from yellow to dark brown in aqueous solutions. The influence on HYD-DAS to Cu (II) adsorption including pH value of solution, isotherm, kinetics, thermodynamics and possible mechanism had also been examined. Batch experiments indicate that HYD-DAS's to Cu (II) adsorption reaches equilibrium within 250 min, and its adsorption capacity and rate are 195.75 mg/g and 98.63 %, respectively. Moreover, HYD-DAS to Cu (II) adsorption remains robust and underscoring after five cycles to exhibit good selectivity and reusability. Kinetics studies suggest the absorption process follows a quasi-second-order with isotherms aligning to the Langmuir monolayer model, and thermodynamics reveals that it is a spontaneous endothermic nature of adsorption. Based on the analyses of XPS and DFT calculations, a possible mechanism for HYD-DAS to Cu (II) adsorption is that Cu (II) combined with nitrogen atoms from Schiff base and hydrazine pyridine ring in HYD-DAS.

6,6'-Diheptyl-3,3'-bis-[(pyridin-3-yl)ethyn-yl]-5H,5'H-di-pyrrolo-[1,2-b:1',2'-g][2,6]naphthyridine-5,5'-dione.

The complete mol-ecule of the title compound, C42H42N4O2, is generated by a crystallographic centre of symmetry. The pendant heptyl chains adopt extended conformations and the dihedral angle between the pyrrole and pyridine rings is 8.18 (15)°. In the crystal, the mol-ecules are arranged in columnar stacks propagating in the [010] direction via slipped aromatic π-π stacking inter-actions.

Pharmacokinetics, pharmacodynamics and safety of LPM3480392 in two phase I clinical trials in healthy Chinese male subjects.

Drugs for acute postoperative pain and breakthrough cancer pain are still urgent in clinical. LPM3480392 is a G-protein-biased ligand at the µ-opioid receptor and showed potent analgesia in nonclinical studies. Two phase I studies of LPM3480392 were conducted in healthy Chinese male volunteers to explore its tolerability, pharmacokinetics and pharmacodynamics under single ascending doses (Study I 0.1-3.0 mg, 30 min) and different infusion times (Study II, 0.6-1.0 mg, 2-15 min). There was one serious adverse event (AE) observed in Study II, and the rest AEs were mild or moderate in severity and resolved by the end of the study. Plasma LPM3480392 maximum concentration (Cmax ) (under lower infusion rate) and area under the plasma concentration-time curve (AUCs) were generally increased with dose. Moreover, LPM3480392 at a dose of 0.6 mg under a 2 min infusion rate elicited effective analgesia as the peak effect within 10-30 min, which was measured by cold pain test and pupillometry. These findings suggest that LPM3480392 could be a potential treatment for acute pain management.

The Role of Polaronic States on the Spin Dynamics in Solution-Processed Two-Dimensional Layered Perovskite with Different Layer Thickness.

2D lead halide perovskites (LHPs) show strong excitonic and spin-orbit coupling effects, generating a facile spin injection. Besides, they possess a polaron character due to the soft crystal lattice, which can prolong the spin lifetime, making them favorable materials for spintronic applications. Here, the spin dynamics of 2D PEA2 PbI4 (MAPbI3 )n -l thin films with different layers by temperature- and pump fluence-dependent circularly polarization-resolved transient absorption (TA) measurements is studied. These results indicate that the spin depolarization mechanism is gradually converted from the Maialle-Silva-Sham (MSS) mechanism to the polaronic states protection mechanism with the layer number increasing from = 1 to 3, which is determined by the interplay between the strength of Coulomb exchange interaction and the strength of polaronic effect. While for ≥ 4, the Elliot-Yafet (EY) impurities mechanism is proposed, in which the formed polaronic states with free charge carriers no longer play the protective role.

Clinical application of parathyroid autotransplantation in endoscopic radical resection of thyroid carcinoma.

Purpose: This study aimed to examine the effect of selective inferior parathyroid gland autotransplantation on central lymph node dissection(CLND) and incidence of postoperative hypoparathyroidism in patients undergoing endoscopic radical resection of thyroid carcinoma. Methods: The data of 310 patients undergoing endoscopic radical resection of thyroid carcinoma will be retrospectively analyzed. The patients will be divided into the experimental group and the control group according to whether they combined with parathyroid autotransplantation. Statistics of the incidence rate of postoperative hypoparathyroidism, the concentration of PTH and Calcium in the systemic circulation at different time points in the two groups, the concentration of PTH in the cubital fossa vein in the transplantation region in the experimental group, and the number of central lymph nodes and positive lymph nodes dissection will be carried out. Results: The incidence rate of temporary and permanent hypoparathyroidism in the experimental group was 33.75% and 0.625%, respectively, and in the control group was 22% and 5%, respectively; its difference was statistically significant (X2 = 10.255, P=0.006). Parathyroid autotransplantation increased incidence of transient hypoparathyroidism (OR, 1.806; Cl, 1.088-2.998; P=0.022), and lower incidence of permanent hypoparathyroidism (OR, 0.112; Cl, 0.014-0.904; P=0.040). The diameters of thyroid cancer nodules was not associated with the occurrence of transient hypoparathyroidism (OR, 0.769; Cl, 0.467-1.265; P=0.301) or permanent hypoparathyroidism (OR, 1.434; Cl, 0.316-6.515; P=0.641). Comparison of systemic circulation PTH, between the two groups showed that the PTH of patients in the experimental group was higher than that in the control group from 1 week to 12 months after the operation, and the difference was statistically significant (P<0.05). In the experimental group, from 1 week to 12 months after surgery, PTH concentrations was significantly higher in the cubital fossa of the transplantation side than in the contralateral side, and the differences were statistically significant (P<0.05). The mean number of central lymph node dissected per patient was significantly higher in the experimental group (7.94 ± 3.03 vs. 6.99 ± 2.86; P <0.05); The mean number of positive nodes per patient was significantly higher in the experimental group (3.16 ± 1.86 vs. 2.53 ± 1.59; P <0.05). Conclusions: In endoscopic radical resection of thyroid carcinoma, parathyroid autotransplantation is more beneficial to postoperative parathyroid glands function recovery, effectively preventing postoperative permanent hypoparathyroidism and realizing more thorough CLND.

Proximity-induced exponential amplification reaction triggered by proteins and small molecules.

We proposed a method to regulate nucleic acid polymerization by proximity and designed an ultrasensitive biosensor based on proximity-induced exponential amplification reaction for proximity assay of proteins (streptavidin) and small molecules (adenosine triphosphate), which allows us to detect a variety of interesting targets by simply changing the binding sites of DNA.

[The anatomic and radiographic morphometry of thoracic pedicle rib unit].

OBJECTIVES: To investigate the spatial structure of pedicle rib units in normal thoracic human spines and to compare the dimensions of the pedicle rib unit with corresponding dimensions. METHODS: Thoracic spine specimens in four fresh adult cadaveric were used. Computerized tomographic (CT) images (including two-dimensional, three-dimensional reconstruction) of the thoracic spines were obtained. Measurement parameters include:the width, the height, the chord length and the sagittal angles of the pedicle rib unit compared with pedicle, especially for the pedicle-rib overlapping height. RESULTS: The pedicle rib unit was not a simple two-dimensional structure but a three-dimensional structure. The shortest height of pedicle rib unit was (12.6 ± 0.8) mm (T(1)), while the longest was (16.9 ± 1.1) mm (T(11)). The shortest height of pedicle-rib overlap was (7.2 ± 0.3) mm (T(1)), while the longest was (11.8 ± 1.0) mm (T(10)). The height of pedicle rib unit and the height of pedicle were significantly larger than that of the pedicle-rib overlap (P < 0.05), while there was no significantly difference between the height of pedicle rib unit and the height of pedicle (P > 0.05). CONCLUSIONS: The pedicle rib unit is a complicated spatial structure, and the longitudinal height of pedicle-rib overlap should be taken as the real height of the unit.