[Analysis of compliance with lung protective mechanical ventilation strategy in patients with acute respiratory distress syndrome]

Objective: To assess the compliance with a lung protective ventilation strategy and to evaluate the relationship with prognosis in patients with acute respiratory distress syndrome (ARDS). Methods: In the prospective multicenter cohort study (CHARDS), patients with ARDS undergoing invasive mechanical ventilation were enrolled to collect essential information, mechanical ventilation data, and prognostic data. Compliance was operationally defined as tidal volume ≤7 ml/kg predicted body weight (PBW) or plateau pressure ≤30 cmH2O or driving pressure≤15 cmH2O. Tidal volume data collected 7 days prior to ventilation after ARDS diagnosis were categorized into four groups: standard group (Group A, 100% compliance), non-standard group (Group B, 50%-99% compliance, Group C,1%-49% compliance,and Group D,totally non-compliant). Plateau pressure and drive pressure measurements were recorded on the first day. Stepwise regression, specifically Logistics regression, was used to identify the factors influencing ICU survival. Results: A total of 449 ARDS patients with invasive mechanical ventilation were included; the proportion of mild, moderate, and severe patients was 71 (15.8%), 198 (44.1%) and 180 (40.1%), respectively. During the first 7 days, a total of 2880 tidal volume measurements were recorded with an average tidal volume of (6.89±1.93) ml/kg PBW. Of these measurements, 53.2% were found to be≤7 ml/kg PBW. The rates of compliance with lung protective mechanical ventilation were 29.8% (134/449), 24.5% (110/449), 23.6% (106/449), and 22% (99/449) in groups A, B, C, and D, respectively. In the standard group, the tidal volume for mild ARDS patients was 18.3%(13/71), while it was 81.7%(58/71)in the non-standard group. Similarly, in patients with moderate ARDS, the tidal volume was 25.8% (51/198) in the standard group, while it was 74.2% (147/198) in the non-standard group. Finally, in patients with severe ARDS, the tidal volume was 38.9% (70/180) in the standard group, while it was 61.1% (110/180) in the non-standard group. Notably, the compliance rate was higher in patients with moderate and severe ARDS in group A compared to patients with mild and moderate ARDS (18.3% vs. 25.8% vs. 38.9%, χ2=13.124, P=0.001). Plateau pressure was recorded in 221 patients, 95.9% (212/221) patients with plateau pressure≤30 cmH2O, and driving pressure was recorded in 207 patients, 77.8% (161/207) patients with a driving pressure ≤15 cmH2O.During the first 7 days, the mortality rate in the intensive care unit (ICU) was lower in the tidal volume standard group compared to the non-standard group (34.6% vs. 51.3%, χ2=10.464, P=0.001). In addition, the in-hospital mortality rate was lower in the standard group compared to the non-standard group (39.8% vs. 57%, χ2=11.016, P=0.001).The results of the subgroup analysis showed that the mortality rates of moderate and severe ARDS patients in the standard group were significantly lower than those in the non-standard group, both in the ICU and in the hospital (all P<0.05). However, there was no statistically significant difference in mortality among mild ARDS patients (all P>0.05). Conclusions: There was high compliance with recommended lung protective mechanical ventilation strategies in ARDS patients, with slightly lower compliance in patients with mild ARDS, and high compliance rates for plateau and drive pressures. The tidal volume full compliance group had a lower mortality than the non-compliance group, and showed a similar trend in the moderate-to-severe ARDS subgroup, but there was no significant correlation between compliance and prognosis in patients with mild ARDS subgroup.

Allosteric Activator-Regulated CRISPR/Cas12a System Enables Biosensing and Imaging of Intracellular Endogenous and Exogenous Targets

Sensors designed based on the trans-cleavage activity of CRISPR/Cas12a systems have opened up a new era in the field of biosensing. The current design of CRISPR/Cas12-based sensors in the "on-off-on" mode mainly focuses on programming the activator strand (AS) to indirectly switch the trans-cleavage activity of Cas12a in response to target information. However, this design usually requires the help of additional auxiliary probes to keep the activator strand in an initially "blocked" state. The length design and dosage of the auxiliary probe need to be strictly optimized to ensure the lowest background and the best signal-to-noise ratio. This will inevitably increase the experiment complexity. To solve this problem, we propose using AS after the "RESET" effect to directly regulate the Cas12a enzymatic activity. Initially, the activator strand was rationally designed to be embedded in a hairpin structure to deprive its ability to activate the CRISPR/Cas12a system. When the target is present, target-mediated strand displacement causes the conformation change in the AS, the hairpin structure is opened, and the CRISPR/Cas12a system is reactivated; the switchable structure of AS can be used to regulate the degree of activation of Cas12a according to the target concentration. Due to the advantages of low background and stability, the CRISPR/Cas12a-based strategy can not only image endogenous biomarkers (miR-21) in living cells but also enable long-term and accurate imaging analysis of the process of exogenous virus invasion of cells. Release and replication of virus genome in host cells are indispensable hallmark events of cell infection by virus; sensitive monitoring of them is of great significance to revealing virus infection mechanism and defending against viral diseases.

Photoactivatable CRISPR/Cas12a Sensors for Biomarkers Imaging and Point-of-Care Diagnostics

In recent years, the CRISPR/Cas12a-based sensing strategy has shown significant potential for specific target detection due to its rapid and sensitive characteristics. However, the "always active" biosensors are often insufficient to manipulate nucleic acid sensing with high spatiotemporal control. It remains crucial to develop nucleic acid sensing devices that can be activated at the desired time and space by a remotely applied stimulus. Here, we integrated photoactivation with the CRISPR/Cas12a system for DNA and RNA detection, aiming to provide high spatiotemporal control for nucleic acid sensing. By rationally designing the target recognition sequence, this photoactivation CRISPR/Cas12a system could recognize HPV16 and survivin, respectively. We combined the lateral flow assay strip test with the CRISPR/Cas12a system to realize the visualization of nucleic acid cleavage signals, displaying potential instant test application capabilities. Additionally, we also successfully realized the temporary control of its fluorescent sensing activity for survivin by photoactivation in vivo, allowing rapid detection of target nucleic acids and avoiding the risk of contamination from premature leaks during storage. Our strategy suggests that the CRISPR/Cas12a platform can be triggered by photoactivation to sense various targets, expanding the technical toolbox for precise biological and medical analysis. This study represents a significant advancement in nucleic acid sensing and has potential applications in disease diagnosis and treatment.

Metal-Induced Energy Transfer (MIET) Imaging of Cell Surface Engineering with Multivalent DNA Nanobrushes

The spacing between cells has a significant impact on cell-cell interactions, which are critical to the fate and function of both individual cells and multicellular organisms. However, accurately measuring the distance between cell membranes and the variations between different membranes has proven to be a challenging task. In this study, we employ metal-induced energy transfer (MIET) imaging/spectroscopy to determine and track the intermembrane distance and variations with nanometer precision. We have developed a DNA-based molecular adhesive called the DNA nanobrush, which serves as a cellular adhesive for connecting the plasma membranes of different cells. By manipulating the number of base pairs within the DNA nanobrush, we can modify various aspects of membrane-membrane interactions such as adhesive directionality, distance, and forces. We demonstrate that such nanometer-level changes can be detected with MIET imaging/spectroscopy. Moreover, we successfully employed MIET to measure distance variations between a cellular plasma membrane and a model membrane. This experiment not only showcases the effectiveness of MIET as a powerful tool for accurately quantifying membrane-membrane interactions but also validates the potential of DNA nanobrushes as cellular adhesives. This innovative method holds significant implications for advancing the study of multicellular interactions.

Low-Background CRISPR/Cas12a Sensors for Versatile Live-Cell Biosensing

The trans-cleavage activity of CRISPR/Cas12a has been widely used in biosensing. However, many CRISPR/Cas12a-based biosensors, especially those that work in "on-off-on" mode, usually suffer from high background and thus impossible intracellular application. Herein, this problem is efficiently overcome by elaborately designing the activator strand (AS) of CRISPR/Cas12a using the "RESET" effect found by our group. The activation ability of the as-designed AS to CRISPR/Cas12a can be easily inhibited, thus assuring a low background for subsequent biosensing applications, which not only benefits the detection sensitivity improvement of CRISPR/Cas12a-based biosensors but also promotes their applications in live cells as well as makes it possible to design high-performance biosensors with greatly improved flexibility, thus achieving the analysis of a wide range of targets. As examples, by using different strategies such as strand displacement, strand cleavage, and aptamer-substrate interaction to reactivate the inhibited enzyme activity, several CRISPR/Cas12a-based biosensing systems are developed for the sensitive and specific detection of different targets, including nucleic acid (miR-21), biological small molecules (ATP), and enzymes (hOGG1), giving the detection limits of 0.96 pM, 8.6 μM, and 8.3 × 10-5 U/mL, respectively. Thanks to the low background, these biosensors are demonstrated to work well for the accurate imaging analysis of different biomolecules in live cells. Moreover, we also demonstrate that these sensing systems can be easily combined with lateral flow assay (LFA), thus holding great potential in point-of-care testing, especially in poorly equipped or nonlaboratory environments.

[Effects of small GTP-binding protein GDP dissociation stimulator on adipocyte hypertrophy and glucose metabolism disorder in mice]

Objective: To explore the effect and mechanism of small GTP-binding protein GDP dissociation stimulator (SmgGDS) on the development of obesity. Methods: (1) 8-week-old C57BL/6J mice were randomly assigned to normal diet and high fat diet group, with 6 mice in each group. They were fed regular feed and a high fat diet containing 60% fat for 4 months, respectively. The expression of SmgGDS in epididymal adipose tissue (eWAT), liver, and skeletal muscle were measured using Western-blot. (2) 6-week-old wild-type (WT) and SmgGDS knockdown (KD) mice were divided into four groups, each receiving high fat diet for 4 months (7 in each group) and 7 months (9 in each group). Glucose tolerance test (GTT) and insulin tolerance test (ITT) were conducted; The weight, adipose tissue, and liver weight of mice were recorded; HE staining examined adipose tissue structural changes; Western-blot determined extracellular signal-regulated kinase (ERK) 1/2 phosphorylation levels in eWAT; Real time fluorescence quantitative polymerase chain reaction (RT-qPCR) was used to detect mRNA levels of CCAAT/enhancer binding protein α (C/EBPα), C/EBPβ and peroxisome proliferator activated receptor γ (PPARγ) in eWAT. (3) Mouse embryonic fibroblasts (MEFs) extracted from WT and KD mice were induced for differentiation. Oil red O staining and Western-blot were used to detect lipid droplet and expression of SmgGDS and phospho-ERK; C/EBPα, C/EBPβ and PPARγ mRNA levels were measured using RT-qPCR. (4) 10-week-old C57BL/6J mice were randomly assigned into two groups, with 7 mice in each group. Mice were infected with SmgGDS overexpressing adeno-associated virus (AAV-SmgGDS) or empty vector intraperitoneally, then fed with high fat diet. After 4 weeks, performed GTT and ITT; Recorded the weight and adipose tissue weight of mice; HE staining was used to analyze structural changes of eWAT; Western-blot was used to detect the phosphorylation level of ERK in eWAT. Results: (1) The expression of SmgGDS was significantly upregulated in eWAT of high fat diet fed mice (normal diet group: 0.218±0.037, high fat diet group:0.439±0.072, t=2.74, P=0.034). (2) At 4 months of high fat diet intervention, the glucose tolerance (60 minutes after glucose injection, WT group: 528 mg/dl±21 mg/dl, KD group: 435 mg/dl±17 mg/dl, t=3.47, P=0.030; 90 minutes, WT group: 463 mg/dl±24 mg/dl, KD group: 366 mg/dl±18 mg/dl, t=3.23, P=0.047;120 minutes, WT group: 416 mg/dl±21 mg/dl, KD group: 297 mg/dl±16 mg/dl, t=4.49, P=0.005) and insulin sensitivity (15 minutes after insulin injection, WT group: 77.79%±3.45%, KD group: 54.30%±2.92%, t=3.49, P=0.005; 30 minutes, WT group: 62.27%±5.31%, KD group: 42.25%±1.85%, t=2.978, P=0.024; 90 minutes, WT group: 85.69%±6.63%, KD group: 64.71%±5.41%, t=3.120, P=0.016) of KD mice were significantly improved compared to the WT group, with an increase in eWAT weight ratio (WT: 4.19%±0.18%, KD: 5.12%±0.37%, t=2.28, P=0.042), but a decrease in average adipocyte area (WT group: 5221 μm²±241 μm², KD group: 4410 μm²±196 μm², t=2.61, P=0.026). After 7 months of high fat diet, the eWAT weight ratio of KD mice decreased (WT: 5.02%±0.20%, KD: 3.88%±0.21%, t=3.92, P=0.001) and adipocyte size decreased (WT group: 6 783 μm²±390 μm², KD group: 4785 μm²±303 μm², t=4.05, P=0.002). The phospho-ERK1 in eWAT increased (WT group: 0.174±0.056, KD group: 0.588±0.147, t=2.64, P=0.025), and mRNA level of PPARγ significantly decreased (WT group: 1.018±0.128, KD group: 0.029±0.015, t=7.70, P=0.015). (3) The expression of SmgGDS was significantly increased in differentiated MEF (undifferentiated: 6.789±0.511, differentiated: 10.170±0.523, t=4.63, P=0.010); SmgGDS knock-down inhibited lipid droplet formation in MEF (WT group: 1.00±0.02, KD group: 0.88±0.02, t=5.05, P=0.007) and increased ERK1 (WT group: 0.600±0.179, KD group: 1.325±0.102, t=3.52, P=0.025) and ERK2 (WT group: 2.179±0.687, KD group: 5.200±0.814, t=2.84, P=0.047) activity, which can be reversed by ERK1/2 inhibitor. (4) SmgGDS over expression resulted in weight gain, increased eWAT weight (control group: 3.29%±0.36%, AAV-SmgGDS group: 4.27%±0.26%, t=2.20, P=0.048) and adipocyte size (control group: 3525 μm²±454 μm², AAV-SmgGDS group: 5326 μm²±655 μm², t=2.26, P=0.047), impaired insulin sensitivity(30 minutes after insulin injection, control group: 44.03%±4.29%, AAV-SmgGDS group: 62.70%±2.81%, t=3.06, P=0.019), and decreased ERK1 (control group: 0.829±0.077, AAV-SmgGDS group: 0.326±0.036, t=5.96, P=0.001)and ERK2 (control group: 5.748±0.287, AAV-SmgGDS group: 2.999±0.845, t=3.08, P=0.022) activity in eWAT. Conclusion: SmgGDS knockdown improves obesity related glucose metabolism disorder by inhibiting adipogenesis and adipose tissue hypertrophy, which is associated with ERK activation.

[A glass micropipette vacuum technique of cerebrospinal fluid sampling in C57BL/6 mice]

The purpose of this study was to establish a suitable method for extracting cerebrospinal fluid (CSF) from C57BL/6 mice. A patch clamp electrode puller was used to draw a glass micropipette, and a brain stereotaxic device was used to fix the mouse's head at an angle of 135° from the body. Under a stereoscopic microscope, the skin and muscle tissue on the back of the mouse's head were separated, and the dura mater at the cerebellomedullary cistern was exposed. The glass micropipette (with an angle of 20° to 30° from the dura mater) was used to puncture at a point 1 mm inboard of Y-shaped dorsal vertebral artery for CSF sampling. After the first extraction, the glass micropipette was connected with a 1 mL sterile syringe to form a negative pressure device for the second extraction. The results showed that the successful rate of CSF extraction was 83.33% (30/36). Average CSF extraction amount was (7.16 ± 0.43) μL per mouse. In addition, C57BL/6 mice were given intranasally ferric ammonium citrate (FAC) to establish a model of brain iron accumulation, and the CSF extraction technique established in the present study was used for sampling. The results showed that iron content in the CSF from the normal saline control group was not detected, while the iron content in the CSF from FAC-treated group was (76.24 ± 38.53) μmol/L, and the difference was significant. These results suggest that glass micropipette vacuum technique of CSF sampling established in the present study has the advantages of simplicity, high success rate, large extraction volume, and low bleeding rate, and is suitable for the research on C57BL/6 mouse neurological disease models.

Lignin-based covalent organic polymers with improved crystallinity for non-targeted analysis of chemical hazards in food samples

Lignin, the most abundant source of renewable aromatic compounds derived from natural lignocellulosic biomass, has great potential for various applications as green materials due to its abundant active groups. However, it is still challenging to quickly construct green polymers with a certain crystallinity by utilizing lignin as a building block. Herein, new green lignin-based covalent organic polymers (LIGOPD-COPs) were one-pot fabricated with water as the reaction solvent and natural lignin as the raw material. Furthermore, by using paraformaldehyde as a protector and modulator, the LIGOPD-COPs prepared under optimized conditions displayed better crystallinity than reported lignin-based polymers, demonstrating the feasibility of preparing lignin-based polymers with improved crystallinity. The improved crystallinity confers LIGOPD-COPs with enhanced application performance, which was demonstrated by their excellent performances in sample treatment of non-targeted food safety analysis. Under optimized conditions, phytochromes, the main interfering matrices, were almost completely removed from different phytochromes-rich vegetables by LIGOPD-COPs, accompanied by "full recovery" of 90 chemical hazards. Green, low-cost, and reusable properties, together with improved crystallinity, will accelerate the industrialization and marketization of lignin-based COPs, and promote their applications in many fields.

Observation of a Strongly Isospin-Mixed Doublet in ^{26}Si via β-Delayed Two-Proton Decay of ^{26}P

β decay of proton-rich nuclei plays an important role in exploring isospin mixing. The β decay of ^{26}P at the proton drip line is studied using double-sided silicon strip detectors operating in conjunction with high-purity germanium detectors. The T=2 isobaric analog state (IAS) at 13 055 keV and two new high-lying states at 13 380 and 11 912 keV in ^{26}Si are unambiguously identified through β-delayed two-proton emission (β2p). Angular correlations of two protons emitted from ^{26}Si excited states populated by ^{26}P β decay are measured, which suggests that the two protons are emitted mainly sequentially. We report the first observation of a strongly isospin-mixed doublet that deexcites mainly via two-proton decay. The isospin mixing matrix element between the ^{26}Si IAS and the nearby 13 380-keV state is determined to be 130(21) keV, and this result represents the strongest mixing, highest excitation energy, and largest level spacing of a doublet ever observed in β-decay experiments.

"RESET" Effect: Random Extending Sequences Enhance the Trans-Cleavage Activity of CRISPR/Cas12a

The trans-cleavage activity of CRISPR/Cas12a has been widely used in biosensing applications. However, the lack of exploration on the fundamental properties of CRISPR/Cas12a not only discourages further in-depth studies of the CRISPR/Cas12a system but also limits the design space of CRISPR/Cas12a-based applications. Herein, a "RESET" effect (random extending sequences enhance trans-cleavage activity) is discovered for the activation of CRISPR/Cas12a trans-cleavage activity. That is, a single-stranded DNA, which is too short to work as the activator, can efficiently activate CRISPR/Cas12a after being extended a random sequence from its 3'-end, even when the random sequence folds into secondary structures. The finding of the "RESET" effect enriches the CRISPR/Cas12a-based sensing strategies. Based on this effect, two CRISPR/Cas12a-based biosensors are designed for the sensitive and specific detection of two biologically important enzymes.

[Effects of postoperative urine protein levels on predicting acute kidney injury in critically ill patients undergoing non-cardiac surgery]

Objective: To investigate the predictive value of postoperative urine protein level in critically ill patients undergoing non-cardiac surgery with acute kidney injury (AKI). Methods: A total of 661 critically ill patients undergoing non-cardiac surgery, who visited the Department of Critical Care Medicine of Peking University First Hospital from May 20, 2019 to November 24, 2020, were enrolled in this prospective study. The clinical data of the patient's age, gender, body mass index, laboratory examination, surgical status, etc. were collected. AKI diagnostic criteria of the 2012 KDIGO guidelines were used to diagnose the occurrence of AKI after surgery. The independent predictors of AKI were determined by multivariate logistic regression. Results: The age of this patient cohort was (69±15) years. The prevalence of AKI was 45.4% (300/661). Multivariate logistic regression showed that urine protein semi-quantitative ≥2+(OR=2.62, 95%CI: 1.05-6.56, P=0.039) was independent factor for postoperative AKI in critically ill patients undergoing non-cardiac surgery, other independent factors include higher age (OR=1.04, 95%CI: 1.02-1.06, P=0.001), higher body mass index (BMI) (OR=1.12, 95%CI: 1.04-1.21, P=0.004), lower plasma hemoglobin level (OR=0.98, 95%CI: 0.97-1.00, P=0.019), lower central venous pressure (OR=0.89, 95%CI: 0.83-0.97, P=0.005) and lower total hypotension time (OR=1.01, 95%CI: 1.00-1.01, P=0.041). Conclusions: Urine protein semi-quantitative ≥2+after surgery is an independent predictive factor for the occurrence of postoperative AKI in critically ill patients undergoing non-cardiac surgery. It is important to check urine routine immediately after surgery to detect and deal with high-risk patients.

Recent advances in constructing high-order DNA structures

Molecular self-assembly is widely used in the fields of biosensors, molecular devices, efficient catalytic materials, and medical biomaterials. As the carrier of genetic information, DNA is a kind of biomacromolecule composed of deoxyribonucleotide units. DNA nanotechnology extends DNA of its original properties as a molecule that stores and transmits genetic information from its biological environment. By taking advantage of its unique base pairing and inherent biocompatibility to produce structurally-defined supramolecular structures. With the continuously development of DNA technology, the assembly method of DNA nanostructures is not only limited on the basis of DNA hybridization but also other biochemical interactions. In this review, we summarize the latest methods used to construct high-order DNA nanostructures. The problems of DNA nanostructures are discussed and the future directions in this field are provided.

A CRISPR/Cas12a-responsive dual-aptamer DNA network for specific capture and controllable release of circulating tumor cells

The separation and detection of circulating tumor cells (CTCs) have a significant impact on clinical diagnosis and treatment by providing a predictive diagnosis of primary tumors and tumor metastasis.

MnO2 nanosheets as a carrier and accelerator for improved live-cell biosensing application of CRISPR/Cas12a

Besides gene-editing, the CRISPR/Cas12a system has also been widely used in in vitro biosensing, but its applications in live-cell biosensing are rare. One reason is lacking appropriate carriers to synchronously deliver all components of the CRISPR/Cas12a system into living cells. Herein, we demonstrate that MnO₂ nanosheets are an excellent carrier of CRISPR/Cas12a due to the two important roles played by them. Through a simple mixing operation, all components of the CRISPR/Cas12a system can be loaded on MnO₂ nanosheets and thus synchronously delivered into cells. Intracellular glutathione (GSH)-induced decomposition of MnO₂ nanosheets not only results in the rapid release of the CRISPR/Cas12a system in cells but also provides Mn²⁺ as an accelerator to promote CRISPR/Cas12a-based biosensing of intracellular targets. Due to the merits of highly efficient delivery, rapid intracellular release, and the accelerated signal output reaction, MnO₂ nanosheets work better than commercial liposome carriers in live-cell biosensing analysis of survivin messenger RNA (mRNA), producing much brighter fluorescence images in a shorter time. The use of MnO₂ nanosheets might provide a good carrier for different CRISPR/Cas systems and achieve the rapid and sensitive live-cell biosensing analysis of different intracellular targets, thus paving a promising way to promote the applications of CRISPR/Cas systems in living cells.

Herein, we demonstrate that MnO₂ nanosheets are an excellent carrier of CRISPR/Cas12a due to the two important roles played by them.

Ferroptosis patterns and tumor microenvironment infiltration characterization in esophageal squamous cell cancer

Background: Esophageal Squamous Cell Cancer (ESCC) is an aggressive disease associated with a poor prognosis. As a newly defined form of regulated cell death, ferroptosis plays a crucial role in cancer development and treatment and might be a promising therapeutic target. However, the expression patterns of ferroptosis-related genes (FRGs) in ESCC remain to be systematically analyzed. Methods: First, we retrieved the transcriptional profile of ESCC from TCGA and GEO datasets (GSE47404, GSE23400, and GSE53625) and performed unsupervised clustering to identify different ferroptosis patterns. Then, we used the ssGSEA algorithm to estimate the immune cell infiltration of these patterns and explored the differences in immune cell abundance. Common genes among patterns were finally identified as signature genes of ferroptosis patterns. Results: Herein, we depicted the multi-omics landscape of FRGs through integrated bioinformatics analysis and identified three ESCC subtypes with distinct immune characteristics: clusters A-C. Cluster C was abundant in CD8⁺ T cells and other immune cell infiltration, while cluster A was immune-barren. By comparing the differently expressed genes between clusters of diverse datasets, we defined a gene signature for each cluster and successfully validated it in the TCGA-ESCC dataset. Conclusion: We provided a comprehensive insight into the expression pattern of ferroptosis genes and their interaction with immune cell infiltration. Additionally, we established a gene signature to define the ferroptosis patterns, which might be used to predict the response to immunotherapy.

DNA nanolantern-mediated catalytic hairpin assembly nanoamplifiers for simultaneous detection of multiple microRNAs

Simultaneous detection of multiple microRNAs (miRNAs) with high sensitivity can give accurate and reliable information for clinical applications. By uniformly anchoring hairpin probes on the surface of DNA nanolantern, a three-dimensional DNA nanostructure contains abundant and adjustable modification sites, highly integrated DNA nanoprobes were designed and developed as catalytic hairpin assembly (CHA)-based signal amplifiers for enzyme-free signal amplification detection of target miRNAs. The nanolantern-based CHA (NLC) amplifiers, which were facilely prepared via a simple "one-pot" annealing method, showed enhanced biostability, improved cell internalization efficiency, accelerated CHA reaction kinetics, and increased signal amplification capability compared to the single-stranded DNA hairpin probes used in traditional CHA reaction. By co-assembling multiple hairpin probes on a DNA nanolantern surface, as-prepared NLC amplifiers were demonstrated to work well for highly sensitive and specific imaging, expression level fluctuation analysis of two miRNAs in living cells, and miRNAs-guided tumor imaging in living mice. The proposed DNA nanolantern-based nanoamplifier strategy might provide a feasible way to promote the cellular and in vivo applications of nucleic acid probes.

Oxidative Cleavage-Based Three-Dimensional DNA Biosensor for Ratiometric Detection of Hypochlorous Acid and Myeloperoxidase

Methods to detect and quantify disease biomarkers with high specificity and sensitivity in biological fluids play a key role in enabling clinical diagnosis, including point-of-care testing. Myeloperoxidase (MPO) is an emerging biomarker for the detection of inflammation, neurodegenerative diseases, and cardiovascular disease, where excess MPO can lead to oxidative damage to biomolecules in homeostatic systems. While numerous methods have been developed for MPO analysis, most techniques are challenging in clinical applications due to the lack of amplification methods, high cost, or other practical drawbacks. Enzyme-linked immunosorbent assays are currently used for the quantification of MPO in clinical practice, which is often limited by the availability of antibodies with high affinity and specificity and the significant nonspecific binding of antibodies to the analytical surface. In contrast, nucleic acid-based biosensors are of interest because of their simplicity, fast response time, low cost, high sensitivity, and low background signal, but detection targets are limited to nucleic acids and non-nucleic acid biomarkers are rare. Recent studies reveal that the modification of a genome in the form of phosphorothioate is specifically sensitive to the oxidative effects of the MPO/H₂O₂/Cl^- system. We developed an oxidative cleavage-based three-dimensional DNA biosensor for rapid, ratiometric detection of HOCl and MPO in a "one-pot" method, which is simple, stable, sensitive, specific, and time-saving and does not require a complex reaction process, such as PCR and enzyme involvement. The constructed biosensor has also been successfully used for MPO detection in complex samples. This strategy is therefore of great value in disease diagnosis and biomedical research.

Signal amplification and output of CRISPR/Cas-based biosensing systems: A review

CRISPR (clustered regularly interspaced short palindromic repeats)/Cas (CRISPR-associated) proteins are powerful gene-editing tools because of their ability to accurately recognize and manipulate nucleic acids. Besides gene-editing function, they also show great promise in biosensing applications due to the superiority of easy design and precise targeting. To improve the performance of CRISPR/Cas-based biosensing systems, various nucleic acid-based signal amplification techniques are elaborately incorporated. The incorporation of these amplification techniques not only greatly increases the detection sensitivity and specificity, but also extends the detectable target range, as well as makes the use of various signal output modes possible. Therefore, summarizing the use of signal amplification techniques in sensing systems and elucidating their roles in improving sensing performance are very necessary for the development of more superior CRISPR/Cas-based biosensors for various applications. In this review, CRISPR/Cas-based biosensors are summarized from two aspects: the incorporation of signal amplification techniques in three kinds of CRISPR/Cas-based biosensing systems (Cas9, Cas12 and Cas13-based ones) and the signal output modes used by these biosensors. The challenges and prospects for the future development of CRISPR/Cas-based biosensors are also discussed.

Nonenzymatic catalytic assembly of valency-controlled DNA architectures for nanoparticles and live cell assembly

The precise control over high-order DNA architecture assembly might be challenging due to complicated circuit design and functional unit synthesis. Here, we show an enzyme-free, catalytic assembly to construct nanometer and micrometer architectures in a bottom-up manner and applied them in nanoparticles and cell assembly.

[Prognosis and related risk factors of acute respiratory distress syndrome in elder patients]

Objective: To study the risk factors associated with the hospital survival rate of elder patients with acute respiratory distress syndrome (ARDS) in Medical/Respiratory Intensive Care Units (MICUs/RICUs) by evaluating the prognosis, and therefore to provide insight into patient treatment strategy. Methods: Twenty MICUs/RICUs of 19 general hospitals in mainland China participated in the multicenter prospective cohort study carried out from Mar 1^st, 2016 to Feb 28^th, 2018. Patients who met the criteria of Berlin ARDS and older than 65 years were recruited. Baseline data, risk factors of ARDS, ventilator setup and prognosis data were collected from all patients. Univariant and multivariant regression analysis were conducted to analyze the factors associated with the prognosis. Results: 170 elder ARDS patients (age≥65 years) met the Berlin ARDS criteria, among whom 8.8% (15/170), 42.9% (73/170) and 48.2% (82/170) patients had mild, moderate and severe ARDS, respectively. The most common predisposing factor for elder ARDS was pneumonia, which was present in 134 patients (78.8%). 37.6% (64/170) patients were treated with noninvasive mechanical ventilation (NIV), but 43.8% (28/64) cases experienced treatment failure. 76.5% (130/170) patients were treated with invasive mechanical ventilation. All patients 80 years or older were given invasive mechanical ventilation. 51.8% (88/170) cases had complications of non-pulmonary organ failure. 61.8% (105/170) patients deceased during hospital stay. Multivariant logistic analysis showed that the independent risk factors for hospital survival rate in elder patients with ARDS were SOFA score (P=0.030, RR=0.725, 95% CI 0.543-0.969), oxygen index after 24 hours of ARDS diagnosis (P=0.030, RR=0.196, 95% CI 0.045-0.853), accumulated fluid balance within 7 days after diagnosis of ARDS (P=0.026, RR=1.000, 95% CI 1.000-1.000) and shock (P=0.034, RR=0.140, 95% CI 0.023-0.863). Conclusion: Among 20 ICUs, the high mortality rate of elder patients with ARDS was correlated with higher 24 hour SOFA score, lower 24 hour oxygen index after ARDS diagnosis, more positive fluid balance within 7 days and concomitant shock. The conservative fluid strategy within 7 days of ARDS diagnosis may benefit the elder ARDS patients.

DNA nanostructure-based nucleic acid probes: construction and biological applications

In recent years, DNA has been widely noted as a kind of material that can be used to construct building blocks for biosensing, in vivo imaging, drug development, and disease therapy because of its advantages of good biocompatibility and programmable properties. However, traditional DNA-based sensing processes are mostly achieved by random diffusion of free DNA probes, which were restricted by limited dynamics and relatively low efficiency. Moreover, in the application of biosystems, single-stranded DNA probes face challenges such as being difficult to internalize into cells and being easily decomposed in the cellular microenvironment. To overcome the above limitations, DNA nanostructure-based probes have attracted intense attention. This kind of probe showed a series of advantages compared to the conventional ones, including increased biostability, enhanced cell internalization efficiency, accelerated reaction rate, and amplified signal output, and thus improved in vitro and in vivo applications. Therefore, reviewing and summarizing the important roles of DNA nanostructures in improving biosensor design is very necessary for the development of DNA nanotechnology and its applications in biology and pharmacology. In this perspective, DNA nanostructure-based probes are reviewed and summarized from several aspects: probe classification according to the dimensions of DNA nanostructures (one, two, and three-dimensional nanostructures), the common connection modes between nucleic acid probes and DNA nanostructures, and the most important advantages of DNA self-assembled nanostructures in the applications of biosensing, imaging analysis, cell assembly, cell capture, and theranostics. Finally, the challenges and prospects for the future development of DNA nanostructure-based nucleic acid probes are also discussed.

DNA nanolantern-based split aptamer probes for in situ ATP imaging in living cells and lighting up mitochondria

Accurate and specific analysis of adenosine triphosphate (ATP) expression levels in living cells can provide valuable information for understanding cell metabolism, physiological activities and pathologic mechanisms. Herein, DNA nanolantern-based split aptamer nanoprobes are prepared and demonstrated to work well for in situ analysis of ATP expression in living cells. The nanoprobes, which carry multiple split aptamer units on the surface, are easily and inexpensively prepared by a "one-pot" assembly reaction of four short oligonucleotide strands. A series of characterization experiments verify that the nanoprobes have good monodispersity, strong biostability, high cell internalization efficiency, and fluorescence resonance energy transfer (FRET)-based ratiometric response to ATP in the concentration range covering the entire intracellular ATP expression level. By changing the intracellular ATP level via different treatments, the nanoprobes are demonstrated to show excellent performance in intracellular ATP expression analysis, giving a highly ATP concentration-dependent ratiometric fluorescence signal output. ATP-induced formation of large-sized DNA aggregates not only amplifies the FRET signal output, but also makes in situ ATP-imaging analysis in living cells possible. In situ responsive crosslinking of nanoprobes also makes them capable of lighting up the mitochondria of living cells. By simply changing the split aptamer sequence, the proposed DNA nanolantern-based split aptamer strategy might be easily extended to other targets.

[Analysis of the self-conscious health status and influencing factors of greenhouse agricultural workers in Beijing suburb]

Objective: To explore the self-conscious health status and related influencing factors of greenhouse agricultural workers in Beijing suburb, so as to provide scientific basis for developing strategies to improve and promote the occupational health conditions of those workers. Methods: According to the production characteristics and scale of the main agricultural districts or counties in the suburb of Beijing, 182 agricultural production personnel were randomly selected to investigate the general situation, occupational situation and self-conscious health status during June 2018 to December 2019. The relevant factors which may affect the self-conscious health conditions were also analyzed by statistical methods. Results: The detection or reported rate of self-conscious health problems was 51.6% (94/182) , among which 29.1% (53/182) workers reported musculoskeletal disorder diseases and 21.4% (39/182) workers reported nervous system diseases. And the self-conscious health status of greenhouse agricultural workers were statistically different in household registration, gender, marital status, working years, mixing or spraying pesticides, smoking or eating in the greenhouse (P<0.05) . Moreover, gender, mixing or spraying pesticide, eating and smoking behavior in the workplace all had an impact on the risk of self-conscious health status of greenhouse agricultural workers (P< 0.05) . Specifically, male is the protective factor to reduce the occurrence of self-conscious symptoms of greenhouse agricultural workers (OR=0.447, 95%CI: 0.234~0.852) , while mixing or spraying pesticides and smoking or eating behaviors in the workplace are the risk factors (OR=1.055, 2.524; 95%CI: 0.503~2.210, 1.107~5.755) . Conclusion: Reducing pesticide use from the source thus minimize related exposure opportunities, strengthening occupational health education thus foster good hygienic habits and improve individual protection consciousness are of great significance for the health protection of greenhouse agricultural workers in Beijing suburb.

Large Isospin Asymmetry in ^{22}Si/^{22}O Mirror Gamow-Teller Transitions Reveals the Halo Structure of ^{22}Al

β-delayed one-proton emissions of ^{22}Si, the lightest nucleus with an isospin projection T_{z}=-3, are studied with a silicon array surrounded by high-purity germanium detectors. Properties of β-decay branches and the reduced transition probabilities for the transitions to the low-lying states of ^{22}Al are determined. Compared to the mirror β decay of ^{22}O, the largest value of mirror asymmetry in low-lying states by far, with δ=209(96), is found in the transition to the first 1^{+} excited state. Shell-model calculation with isospin-nonconserving forces, including the T=1, J=2, 3 interaction related to the s_{1/2} orbit that introduces explicitly the isospin-symmetry breaking force and describes the loosely bound nature of the wave functions of the s_{1/2} orbit, can reproduce the observed data well and consistently explain the observation that a large δ value occurs for the first but not for the second 1^{+} excited state of ^{22}Al. Our results, while supporting the proton-halo structure in ^{22}Al, might provide another means to identify halo nuclei.

Green Layer-by-Layer Assembly of Porphyrin/G-Quadruplex-Based Near-Infrared Nanocomposite Photosensitizer with High Biocompatibility and Bioavailability

A simple and green layer-by-layer assembly strategy is developed for the preparation of a highly bioavailable nanocomposite photosensitizer by assembling near-infrared (NIR) light-sensitive porphyrin/G-quadruplex complexes on the surface of a highly biocompatible nanoparticle that is prepared via Zn²⁺-assisted coordination self-assembly of an amphiphilic amino acid. After being efficiently delivered to the target site and internalized into tumor cells via enhanced permeability and retention effect and interactions between aptamers and tumor markers, the as-prepared nanoassembly can be directly used as an NIR light-responsive photosensitizer for tumor photodynamic therapy (PDT) since the porphyrin/G-quadruplex complexes are exposed on the nanoassembly surface and kept in an active state. It can also disassemble under the synergistic stimuli of an acidic pH environment and overexpressed glutathione, leasing more efficient porphyrin/G-quadruplex composite photosensitizers while reducing the interference caused by glutathione-dependent ¹O₂ consumption. Since the nanoassembly can work no matter if it is disassembled or not, the compulsory requirement for in vivo photosensitizer release is eliminated, thus resulting in the great improvement of the bioavailability of the photosensitizer. The PDT applications of the nanoassembly were well demonstrated in both in vitro cell and in vivo animal experiments.

Seed-borne endophytic Bacillus velezensis LHSB1 mediate the biocontrol of peanut stem rot caused by Sclerotium rolfsii

AIMS

This study aimed to obtain an antagonistic endophyte against Sclerotium rolfsii from peanut seeds, evaluate the biocontrol efficacy towards peanut stem rot and explore its antifungal mechanism against S. rolfsii.

METHODS AND RESULTS

Thirty-seven endophytic bacteria were isolated from peanut seeds, six of which exhibited stronger antagonistic activities against S. rolfsii (inhibition rate, IR of hyphae growth ≥70%). Strain LHSB1, the strongest antagonistic strain, was identified as Bacillus velezensis. LHSB1 showed 93·8% of radial growth inhibition of S. rolfsii hyphae and exhibited obvious antagonistic activity against another six pathogenic fungi of peanut. Pot experiments showed two different LHSB1 treatments both significantly reduced the disease incidence and severity of stem rot (P < 0·05) compared to the controls, and the biocontrol efficacy reached 62·6-70·8%, significantly higher than that of Carbendazim control (P < 0·05). Further analyses revealed LHSB1 culture filtrate significantly inhibited sclerotia formation and germination, caused the abnormalities and membrane integrity damage of S. rolfsii hyphae, which might be the possible mode of action of LHSB1 against S. rolfsii. Three antifungal lipopeptides bacillomycin A, surfactin A and fengycin A, were detected in LHSB1 culture extracts by UPLC-ESI-MS, which could be responsible for the biocontrol activity of LHSB1 against S. rolfsii.

CONCLUSION

Our results suggested that the seed-borne endophytic B. velezensis LHSB1 would be a tremendous potential agent for the biocontrol of peanut stem rot caused by S. rolfsii.

SIGNIFICANCE AND IMPACT OF THE STUDY

This comprehensive study provides a candidate endophytic biocontrol strain and reveals its antifungal mechanism against S. rolfsi. To the best of our knowledge, this is the first time that seed-borne endophytic B. velezensis was used as the biocontrol agent to control peanut stem rot.

Three-dimensional DNA nanostructures to improve the hyperbranched hybridization chain reaction

Nonenzymatic nucleic acid amplification techniques (e.g. the hybridization chain reaction, HCR) have shown promising potential for amplified detection of biomarkers.

Nonenzymatic nucleic acid amplification techniques (e.g. the hybridization chain reaction, HCR) have shown promising potential for amplified detection of biomarkers. However, the traditional HCR occurs through random diffusion of DNA hairpins, making the kinetics and efficiency quite low. By assembling DNA hairpins at the vertexes of tetrahedral DNA nanostructures (TDNs), the reaction kinetics of the HCR is greatly accelerated due to the synergetic contributions of multiple reaction orientations, increased collision probability and enhanced local concentrations. The proposed quadrivalent TDN (qTDN)-mediated hyperbranched HCR has a ∼70-fold faster reaction rate than the traditional HCR. The approximately 76% fluorescence resonance energy transfer (FRET) efficiency obtained is the highest in the reported DNA-based FRET sensing systems as far as we know. Moreover, qTDNs modified by hairpins can easily load drugs, freely traverse plasma membranes and be rapidly cross-linked via the target-triggered HCR in live cells. The reduced freedom of movement as a result of the large crosslinked structure might constrain the hyperbranched HCR in a confined environment, thus making it a promising candidate for in situ imaging and photodynamic therapy. Hence, we present a paradigm of perfect integration of DNA nanotechnology with nucleic acid amplification, thus paving a promising way to the improved performance of nucleic acid amplification techniques and their wider application.

[Risk factors of postoperative complications after laparoscopic surgery for pheochromocytoma]

Objective: To investigate the effects of intraoperative hemodynamic instability on postoperative complications of laparoscopic surgery for pheochromocytoma. Methods: It was a retrospective cohort study. According to inclusion/exclusion criteria, adult patients underwent laparoscopic surgery for pheochromocytoma from January 2005 to December 2017 in Peking University First Hospital were enrolled in this study. Eligible patients were divided into two groups by evidence of postoperative complications to find out the effects of intraoperative hemodynamic instability and its' effects on other prognostic indices. The normally distributed continuous variables were compared between two groups by Student's t test, Mann-Whitney U test were used for the comparison for non-normally distributed continuous variables and χ(2) test for categorical variables. Results: A total of 198 patients were finally enrolled in this study, including 87 males and 111 females with an average age of (47±15) years. Postoperative complications occurred in 17 patients with an incidence of 8.6%, and intraoperative hemodynamic instability occurred in 45 patients (22.7%). It was found that history of stroke[odds ratio (OR)=13.387, 95% confidence interval (CI): 2.284-78.460, P=0.004], intraoperative hemodynamic instability (OR=3.351, 95%CI: 1.119-10.039, P=0.031) and intraoperative positive fluid balance (for each additional 100 ml) (OR=1.087, 95%CI: 1.031-1.146, P=0.002)were the independent risk factors of postoperative complications of laparoscopic surgery for pheochromocytoma. Furthermore, more postoperative complications, higher rate of admitting to ICU and longer hospital stay was found in patients with hemodynamic instability. Conclusion: Intraoperative hemodynamic instability is an independent risk factor for postoperative complications of laparoscopic surgery in patients with pheochromocytoma, and it associates with more postoperative complications and higher rate of admitting to ICU.

High flow nasal cannula compared with conventional oxygen therapy for acute hypoxemic respiratory failure: a systematic review and meta-analysis

BACKGROUND

This systematic review and meta-analysis summarizes the safety and efficacy of high flow nasal cannula (HFNC) in patients with acute hypoxemic respiratory failure.

METHODS

We performed a comprehensive search of MEDLINE, EMBASE, and Web of Science. We identified randomized controlled trials that compared HFNC to conventional oxygen therapy. We pooled data and report summary estimates of effect using relative risk for dichotomous outcomes and mean difference or standardized mean difference for continuous outcomes, with 95% confidence intervals. We assessed risk of bias of included studies using the Cochrane tool and certainty in pooled effect estimates using GRADE methods.

RESULTS

We included 9 RCTs (n = 2093 patients). We found no difference in mortality in patients treated with HFNC (relative risk [RR] 0.94, 95% confidence interval [CI] 0.67-1.31, moderate certainty) compared to conventional oxygen therapy. We found a decreased risk of requiring intubation (RR 0.85, 95% CI 0.74-0.99) or escalation of oxygen therapy (defined as crossover to HFNC in the control group, or initiation of non-invasive ventilation or invasive mechanical ventilation in either group) favouring HFNC-treated patients (RR 0.71, 95% CI 0.51-0.98), although certainty in both outcomes was low due to imprecision and issues related to risk of bias. HFNC had no effect on intensive care unit length of stay (mean difference [MD] 1.38 days more, 95% CI 0.90 days fewer to 3.66 days more, low certainty), hospital length of stay (MD 0.85 days fewer, 95% CI 2.07 days fewer to 0.37 days more, moderate certainty), patient reported comfort (SMD 0.12 lower, 95% CI 0.61 lower to 0.37 higher, very low certainty) or patient reported dyspnea (standardized mean difference [SMD] 0.16 lower, 95% CI 1.10 lower to 1.42 higher, low certainty). Complications of treatment were variably reported amongst included studies, but little harm was associated with HFNC use.

CONCLUSION

In patients with acute hypoxemic respiratory failure, HFNC may decrease the need for tracheal intubation without impacting mortality.

Dinuclear HgII tetracarbene complex-triggered aggregation-induced emission for rapid and selective sensing of Hg2+ and organomercury species

Mercury-mediated chelate ring formation and subsequent aggregation gives strong fluorescence for rapid and selective sensing of Hg²⁺ and organomercury.

Rapid, reliable and highly selective detection of mercury species, including Hg²⁺ ions and organomercury, is of significant importance for environmental protection and human health. Herein, a new fluorescent dye 1,1,2,2-tetrakis[4-(3-methyl-1H-benzimidazol-1-yl)phenyl ethylene tetraiodide (Tmbipe) with aggregation-induced emission (AIE) potential was prepared and characterized. The presence of four positively charged methylated benzimidazole groups endows Tmbipe with excellent water solubility and almost undetectable background fluorescence. However, it can coordinate with two Hg²⁺ ions or two organomercury molecules (e.g. methylmercury and phenylmercury) to form a planar dinuclear Hg^II tetracarbene complex, which can then self-aggregate to turn on AIE fluorescence. Such a fluorescence turn-on process can be completed in 3 min. In addition, synergic rigidification of the tetraphenylethylene-bridged Tmbipe molecule by mercury-mediated chelate ring formation and subsequent aggregation results in obviously higher fluorescence enhancement than that given by the single aggregation-induced one. Low background, high fluorescence enhancement and rapid response time make Tmbipe a good fluorescent probe for reliable, sensitive and highly selective quantitation of both inorganic and organic mercury species. This probe was also demonstrated to work well for identification of mercury species accumulation in living cells.

Dexmedetomidine enhances ropivacaine-induced sciatic nerve injury in diabetic rats

BACKGROUND

Previous studies suggest that dexmedetomidine has a protective effect against local anaesthetic-induced nerve injury in regional nerve blocks. Whether this potentially protective effect exists in the context of diabetes mellitus is unknown.

METHODS

A diabetic state was established in adult male Sprague-Dawley rats with intraperitoneal injection of streptozotocin. Injections of ropivacaine 0.5%, dexmedetomidine 20 μg kg^-1 (alone and in combination), or normal saline (all in 0.2 ml) were made around the sciatic nerve in control and diabetic rats (n=8 per group). The duration of sensory and motor nerve block and the motor nerve conduction velocity (MNCV) were determined. Sciatic nerves were harvested at post-injection day 7 and assessed with light and electron microscopy or used for pro-inflammatory cytokine measurements.

RESULTS

Ropivacaine and dexmedetomidine alone or in combination did not produce nerve fibre damage in control non-diabetic rats. In diabetic rats, ropivacaine induced significant nerve fibre damage, which was enhanced by dexmedetomidine. This manifested with slowed MNCV, decreased axon density, and decreased ratio of inner to outer diameter of the myelin sheath (G ratio). Demyelination, axon disappearance, and empty vacuoles were also found using electron microscopy. An associated increase in nerve interleukin-1β and tumour necrosis factor-α was also seen.

CONCLUSIONS

Ropivacaine 0.5% causes significant sciatic nerve injury in diabetic rats that is greatly potentiated by high-dose dexmedetomidine. Although the dose of dexmedetomidine used in this study is considerably higher than that used in clinical practice, our data suggest that further studies to assess ropivacaine (alone and in combination with dexmedetomidine) use for peripheral nerve blockade in diabetic patients are warranted.

[Perioperative management of pregnant women combined with congenital fibrinogen deficiency: four cases report and literature review]

Congenital fibrinogen deficiency is an autosomal recessive or dominant disorder in which quantitative (afibrinogenaemia or hypofibrinogenaemia) or qualitative (dysfibrinogenaemia) defects in the fibrinogen Aa, Bb or c protein chains that lead to reduced functional fibrinogen. We now report the perioperative management of 4 pregnant women suffering from hypofibrinogenaemia scheduled for elective caesarean section from December 2012 to October 2016 in Peking University First Hospital and review this disease with reference to classification, symptom, replacement therapy, and selection of the modes of pregnancy termination and anesthesia. The four patients were all asymptomatic, whereas there existed recurrent pregnancy loss (case 3), family history (case 2), and offspring heredity (cases 3 and 4). Routine clotting studies revealed low fibrinogen levels and prolonged thrombin time (TT) during pregnancy and on admission. However, the platelet (PLT) count, prothrombin time (PT) and activated partial thromboplastin time (APTT) were normal. All the patients were administered fibrinogen concentrate perioperatively, and underwent uncomplicated combined spinal-epidural anesthesia and uneventful surgical procedure without postpartum hemorrhage. The replacement therapy of fibrinogen or fresh frozen plasma administration was essential to avoid anesthesia and obstetric complications. Regional blockade could safely be offered in the caesarean section, providing that their coagulation defect was corrected by availability of therapeutic products and adequate response to treatment. In addition, the point-of-care rotational thrombelastometry (ROTEM) or thrombelastogram (TEG) could play an important role in an optimal perioperative management for such patients. Management plans must be tailored to each individual, taking into consideration their bleeding risk as well as potential maternal and neonatal complications.

Cav-1 promotes atherosclerosis by activating JNK-associated signaling

The objective of the study is to calculate the role and underlying the molecular mechanisms of caveolin-1 (Cav-1) in atherosclerosis (AS). Cav-1 was mainly expressed in the endothelial cells of atherosclerotic lesions in both human patients and apolipoprotein E deficient (ApoE^-/-) mice. Cav-1 deficiency (Cav-1^-/-) attenuated high-fat diet (HFD)-induced atherosclerotic lesions in ApoE^-/- mice, supported by the reduced aortic plaques. Cav-1^-/- reduced the macrophage content and decreased the release of inflammation-related cytokines or chemokine in serum or abdominal aortas, accompanied with the inactivation of inhibitor κB kinase κ (IKKβ)/p65/IκBα signaling pathway. Also, the activity of mitogen-activated protein kinases 7/c-Jun-N-terminal kinase (MKK7/JNK) signaling was decreased by Cav-1^-/-. In addition, oxidative stress induced by HFD in ApoE^-/- mice was alleviated by Cav-1^-/-. In response to HFD, Cav-1^-/- markedly reduced triglyceride (TG), total cholesterol (TC), low-density lipoprotein-cholesterol (LDLC) and very low-density lipoprotein-cholesterol (VLDLC) in serum of HFD-fed ApoE^-/- mice, whereas enhanced high-density lipoprotein-cholesterol (HDLC) contents. Consistent with these findings, haematoxylin and eosin (H&E) and Oil Red O staining showed fewer lipid droplets in the liver of Cav-1-deficient mice. Further, real time-quantitative PCR (RT-qPCR) analysis indicated that Cav-1^-/- alleviated dyslipidemia both in liver and abdominal aortas of ApoE^-/- mice fed with HFD. Cav-1 inhibition-induced attenuation of inflammatory response, oxidative stress and dyslipidemia were confirmed in vitro using mouse vascular smooth muscle cells (VSMCs) treated with ox-LDL. Surprisingly, the processes regulated by Cav-1-knockdown could be abolished through promoting JNK activation in ox-LDL-treated VSMCs. In conclusion, Cav-1 expression could promote HFD-induced AS in a JNK-dependent manner.

[GBA mutations and Parkinson's disease]

Parkinson's disease (PD) is a common neurodegenerative disease characterized by the degeneration of dopaminergic neurons in the substantia nigra and the intraneuronal Lewy bodies in this area. Genetic mutations in PD pathogenesis have been explored and better understood in recent years. GBA variants are now considered to be the single largest risk factor for PD. Gaucher disease (GD) is a lysosomal storage disorder disease and an inherited deficiency of lysosomal glucocerebrosidase (GCase) arising from mutations in the gene GBA. A group of patients with GD exhibit parkinsonian symptoms, meanwhile, GBA mutations are more frequently observed in patients with PD. These lines of evidence suggest a close relationship between GBA mutations and PD. GBA mutations are associated with an earlier onset age and a distinct cognitive decline in PD. GCase loss-of-function caused by GBA mutations interferes with the degradation of α-synuclein, and α-synuclein pathology in turn inhibits normal GCase function in PD, which forms a vicious cycle. However, the exact mechanisms for this bidirectional pathogenic loop have not to be fully elucidated. In this review, we summarize the current understandings on the potential link between GBA mutations and PD pathogenesis, which may show novel insights into PD etiology and therapeutics.

[Expression of osteoprotegerin and receptor activator of nuclear factor kappa-B ligand in mandibular ramus osteotomy healing with administration of different doses of parathyroid hormone]

Objective: To investigate the effect of parathyroid hormone (PTH) on the bone healing of mandibular ramus osteotomy. Methods: The mandibular ramus osteotomy model was established in sixty rabbits and these rabbits were randomly divided into experimental group A, experimental group B and control group. In the experimental group A and experimental group B, the rabbits were given PTH (20 and 40 μg/kg respectively) every other day after operation. In the control group, 1 ml saline was given. The animals were sacrificed at 1 week, 2 weeks, 3 weeks and 4 weeks postoperatively. The new bone formation was observed by histology and cone bone CT. The expression of osteoprotegerin and receptor activator of nuclear factor kappa-B (RANKL) in the new bone was detected by real-time quantitative PCR. Results: The experimental groups has better osteogenesis and the bone mineral density than the control group in osteotomy area. The experimental group B showed the best osteogenesis.Osteoprotegerin mRNA expression in experimental group A (1.127±0.035, 1.742±0.049, 1.049±0.062, 1.063±0.036) was significantly higher than that in the control group in each period (0.965±0.082, 1.254±0.071, 0.793±0.061, 0.684±0.055) (P=0.010, P=0.000, P=0.001, P=0.020), while group B (1.416±0.205, 2.648±0.168, 1.652±0.091, 1.712±0.070) was significantly higher than group A (P=0.000, P=0.010, P=0.023, P=0.003). RANKL mRNA expression in control group (1.666±0.086, 1.058±0.105, 0.885±0.124, 0.972±0.136) was significantly higher than that of the group A (0.788±0.036, 0.585±0.017, 0.692±0.017, 0.527±0.051) (P=0.001, P=0.006, P=0.003, P=0.028) in each period, while group A was significantly higher than group B(0.247±0.022, 0.240±0.034, 0.134±0.011, 0.103±0.050) (P=0.000, P=0.001, P=0.002, P=0.012). Conclusions: PTH can upregulate the expression of osteoprotegerin and reduce expression of RANKL, thus promoting new bone formation. Intermittent administration of high dose of parathyroid hormone can further promote the healing process after mandibular ramus osteotomy.

The expression change of RORγt, BATF, and IL-17 in Chinese vitiligo patients with 308 nanometers excimer laser treatment

This study aims to explore the expression of RORγt, BATF, and IL-17 in Chinese vitiligo patients with 308 nm excimer laser treatment. One hundred and sixty-four vitiligo patients treated with 308 nm excimer laser were enrolled as Case group and 137 health examiners as Control group. Quantitative real-time polymerase chain reaction and immunohistochemistry were conducted to detect the expressions of RORγt, BATF, and IL-17. Expression of RORγt, BATF, IL-17A, and IL-17F were higher in Case group than Control group, with the diagnostic accuracy of 88.04, 87.38, 97.34, and 89.04%, respectively. Pearson correlation analysis showed a positive correlation in RORγt, BATF, IL-17A, and IL-17F mRNAs in vitiligo patients. Moreover, their expressions were higher in active vitiligo patients than stable ones. Besides, the expressions of RORγt, BATF, IL-17A, and IL-17F in vitiligo skin were significantly higher than those in non lesional skin and normal controls. After treatment, their expressions were significantly decreased. Active vitiligo and the high expressions of RORγt, BATF, and IL-17F were the independent risk factors for the ineffectiveness of 308 nm excimer laser treatment. The expressions of RORγt, BATF, IL-17 were significantly enhanced in vitiligo patients, which were correlated with the activity of vitiligo and 308 nm excimer laser therapeutic effects.

[Effects of recent upper respiratory-tract infections on incidence of the perioperative respiratory adverse events in children: a prospective cohort study]

OBJECTIVE

To investigate the effects of the recent upper respiratory tract infections (URI) on the incidence of perioperative respiratory adverse events in children scheduled to undergo general anesthesia and elective surgery.

METHODS

In the study, 232 children undergoing general anesthesia with laryngeal mask airway (LMA) for elective ophthalmic surgeries at Peking University First Hospital, Beijing, China, from Nov. 1, 2015 to May 10, 2016 were enrolled. On the day of the surgery, the parents of the children were preoperatively asked to fill out a questionnaire regarding the baseline characteristics and medical history of the children, including gender, age, height, weight, history of URI within the last 2 weeks before anesthesia, history of premature, long-term passive smoking exposure, habitual sleep snoring, and history of asthma. In addition, all adverse respiratory events throughout the perioperative periods (oxygen desaturation, cough, copious secretions, laryngospasm and bronchospasm) as well as peri-operative variables (number of attempts to insert the LMA successfully, anesthesia duration and so on) were recorded. Multivariate Logistic regression analysis was applied to identify independent risk factors of perioperative respiratory adverse events.

RESULTS

Among the 232 children included in the study, 28.0% (65/232) presented with a history of a recent URI within the last 2 weeks before anesthesia. The presence of the recent URI increased the incidence of oxygen desaturation (23.1% vs.12.0%, P=0.034), copious secretions (15.4% vs. 6.6%, P=0.036) and any of all the adverse respiratory events (32.3% vs. 18.6%, P=0.024). Multivariate Logistic regression analysis identified two independent risk factors of perioperative adverse respiratory events: a history of URI within the last 2 weeks before general anesthesia (OR=2.021, 95%CI: 1.023-3.994, P=0.043) and habitual sleep snoring (OR=3.660, 95%CI: 1.517-8.832, P=0.004).

CONCLUSION

A history of a recent URI within 2 weeks before general anesthesia was associated with a higher incidence of oxygen desaturation, copious secretions and the overall respiratory adverse events. For the children with recent URI, we recommend the general anesthesia and elective surgery should be postponed for at least 2 weeks after the URI.

[Study on the appropriate parameters of automatic full crown tooth preparation for dental tooth preparation robot]

Objective: To further study the most suitable parameters for automatic full crown preparation using oral clinical micro robot. Its purpose is to improve the quality of automated tooth preparing for the system and to lay the foundation for clinical application. Methods: Twenty selected artificial resin teeth were used as sample teeth. The micro robot automatic tooth preparation system was used in dental clinic to control the picosecond laser beam to complete two dimensional cutting on the resin tooth sample according to the motion planning path. Using the laser scanning measuring microscope, each layer of cutting depth values was obtained and the average value was calculated. The monolayer cutting depth was determined. The three-dimensional (3D) data of the target resin teeth was obtained using internal scanner, and the CAD data of full-crown tooth preparation was designed by CAD self-develged software. According to the depth of the single layer, 11 complete resin teeth in phantom head were automatically prepared by the robot controlling the laser focused spot in accordance with the layer-cutting way. And the accuracy of resin tooth preparation was evaluated with the software. Using the same method, monolayer cutting depth parameter for cutting dental hard tissue was obtained. Then 15 extracted mandibular and maxillary first molars went through automatic full crown tooth preparation. And the 3D data of tooth preparations were obtained with intra oral scanner. The software was used to evaluate the accuracy of tooth preparation. Results: The results indicated that the single cutting depth of cutting resin teeth and in vitro teeth by picosecond laser were (60.0±2.6) and (45.0±3.6) μm, respectively. Using the tooth preparation robot, 11 artificial resin teeth and 15 complete natural teeth were automatically prepared, and the average time were (13.0±0.7), (17.0±1.8) min respectively. Through software evaluation, the average preparation depth of the occlusal surface of 11 resin teeth was approximately (2.089±0.026) mm, the error was about (0.089±0.026) mm; the average convergence angle was about 6.56°±0.30°, the error was about 0.56°±0.30°. Compared with the target preparation shape, the average shape error of the 11 resin tooth preparations was about 0.02-0.11 mm. And the average preparation depth of the occlusal surface of 15 natural teeth was approximately (2.097±0.022) mm, the error was about (0.097±0.022) mm; the average convergence angle was about 6.98°±0.35°, the error was about 0.98°±0.35°. Compared with the target preparation shape, the average shape error of the 15 natural tooth preparations was about 0.05-0.17 mm. Conclusions: The experimental results indicate that the automatic tooth preparation for resin teeth and the teeth were completed according to the specific parameters of the single cutting depth by the micro robot controlling picosecond laser respectively, its preparation accuracy met the clinical needs. And the suitability of the parameter was confirmed.

Antidepressant effects of Kai-Xin-San in fluoxetine-resistant depression rats

This study aimed to investigate the antidepressant effect and the mechanism of action of Kai-Xin-San (KXS) in fluoxetine-resistant depressive (FRD) rats. Two hundred male Wistar rats weighing 200±10 g were exposed to chronic and unpredictable mild stresses (CUMS) for 4 weeks and given fluoxetine treatment simultaneously. The rats that did not show significant improvement in behavioral indexes were chosen as the FRD model rats. These rats were randomly divided into four groups: FRD model control; oral fluoxetine and aspirin; oral KXS at a dose of 338 mg·kg-1·day-1; and oral KXS at a dose of 676 mg·kg-1·day-1. Rats continued to be exposed to CUMS and underwent treatment once a day for 3 weeks, then cytokine (COX-2, IFN-γ, IL-1β, IL-2, IL-4, IL-6, IL-10, TGF-β, and TNF-α) levels in the hippocampus and serum, and organ coefficients were measured. Both doses of KXS improved the crossing and rearing frequencies, sucrose-preference index, and body weight in FRD rats. KXS at a dose of 338 mg·kg-1·day-1reduced COX-2, IL-2, IL-6, TNF-α levels, increased IL-10 level in the hippocampus, and reduced IL-2 and TNF-α levels in serum. KXS at a dose of 676 mg·kg-1·day-1reduced TNF-α level in the hippocampus, reduced IL-2 and TNF-α levels in serum, and increased IFN-γ and IL-10 levels in the hippocampus and serum. There were no significant differences in organ-coefficients of the spleen among and between groups. The results suggested that oral administration of KXS in FRD rats was effective in improving behavior disorders by influencing various inflammatory pathways.

[Effects of apolipoprotein E deficiency on sphingosine-1-phosphate distribution in plasma and lipoproteins of mice]

Objective: To investigate the effects of apolipoprotein E deficiency (Apo E(-/-)) on plasma and lipoprotein distribution of sphingosine-1-phosphate (S1P) in mice. Methods: Five male or female Apo E(-/-) or wild type (WT) mice were fed with chow diet and sacrificed at 32-week-age and plasma was collected. The constituents of lipoprotein(very low density lipoprotein (VLDL), low density lipoprotein (LDL), high density lipoprotein (HDL)) were separated by ultracentrifuge. The protein concentration of constituents was detected by BCA protein quantitative kit, and the S1P concentration in plasma and various lipoprotein constituents was detected by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Western blot was used to determine the plasma, liver, and kidney protein expression of apolipoprotein M(Apo M), which is considered as specific ligand of S1P.The S1P concentration in plasma and various constituents of lipoprotein in the Apo E(-/-) mice was compared to respective WT mice. Results: (1)Plasma S1P content was significantly higher in the Apo E(-/-) groups than that of WT groups (male: (535.7±78.5)nmol/L vs. (263.3±22.0)nmol/L; female: (601.1±64.0)nmol/L vs. (279.0±33.9)nmol/L; all P<0.01). (2) Compared with WT mice, S1P content in non-HDL(LDL+ VLDL) was significantly higher in Apo E(-/-) mice (male: (504.9±52.8)nmol/L vs. (28.7±9.0)nmol/L; female: (427.7±27.4) vs. (27.8±4.7)nmol/L; after standardization of protein concentration, male: (385.0±41.2)pmol/mg protein vs. (71.4±6.6)pmol/mg protein; female: (330.2±22.0)pmol/mg protein vs. (67.2±12.1)pmol/mg protein; all P<0.01). (3) The expression of Apo M in plasma, liver and kidney was significantly higher in Apo E(-/-) groups than that of WT groups(all P<0.05). Conclusion: The deficiency of Apo E could lead to upregulated S1P expression in the non-HDL, the underlying mechanism might be the increased transfer of HDL into the non-HDL by Apo M-S1P.

Is the Dispersion Relation Applicable for Exotic Nuclear Systems? The Abnormal Threshold Anomaly in the ^{6}He+^{209}Bi System

The threshold anomaly of the phenomenological potential has been known for a long time in nuclear reactions at energies around the Coulomb barrier, where the connection between the real and imaginary potentials is well described by the dispersion relation. However, this connection is not clear yet for some weakly bound nuclear systems, especially for reactions induced by exotic radioactive nuclei. In this study, precise optical potentials of the halo nuclear system ^{6}He+^{209}Bi were extracted via ^{208}Pb(^{7}Li,^{6}He) transfer reactions with energies measured downward to the extremely sub-barrier region. The real potential presents a bell-like shape around the barrier as a normal threshold anomaly in tightly bound nuclear systems. However, the imaginary potential shows an abnormal behavior: it increases first with energy decreasing below the barrier and then falls quickly down to 0. It is the first time the threshold of the imaginary potential has been determined in an exotic nuclear system. Moreover, experimental results show the dispersion relation is not applicable for this system, which may be a common phenomenon for exotic nuclear systems. We discuss possible explanations for such a peculiar behavior, but further study is still desired for the underlying physics.

Current Use of Oral Anticoagulants and Prognostic Analysis in Patients with Atrial Fibrillation Undergoing Coronary Stenting

Background:

It is currently believed that triple oral antithrombotic therapy in patients with atrial fibrillation (AF) after percutaneous coronary intervention (PCI) should be recommended if there are no contraindications. However, selecting triple therapy for AF patients undergoing PCI is still challenging when bleeding risk is considered. This study aimed to investigate the current use of oral anticoagulants (Vitamin K antagonists [VKA]) and perform prognostic analysis in real-world patients with AF undergoing coronary stenting.

Methods:

A total of 276 consecutive coronary artery disease (CAD) patients with or without AF undergoing coronary stenting were retrospectively evaluated and analyzed. The univariate and multivariate analyses were conducted to explore the current use of VKA and prognosis of patients with AF undergoing coronary stenting. The primary end-point was composite of all-cause death, nonfatal recurrent myocardial infarction, stroke, serious bleeding events, unplanned repeat revascularization, and worsening heart failure at 12-month follow-up after coronary stenting.

Results:

AF patients undergoing coronary stenting have more clinical concomitant diseases. Only 9.0% AF patients after coronary stenting received triple antithrombotic therapy (VKA, aspirin, and clopidogrel) at discharge. AF was independently associated with increased risk of the 12-month composite end-points (relative risk = 5.732, 95% confidence interval 1.786–18.396, P = 0.003).

Conclusions:

In real-life AF patients undergoing coronary stenting, guideline-recommended VKA was less used. AF patients had adjusted worse prognosis during 12-month follow-up after discharge. It is of utmost importance to improve the current status of oral anticoagulants use.

The value of Sonoclot detection technology to guide the clinical medication of the perioperative anticoagulation and antiplatelet therapy in patients with acute myocardial infarction undergoing emergent PCI

The value of Sonoclot detection technology to guide the clinical medication of the perioperative anticoagulation and antiplatelet therapy in patients with acute myocardial infarction (AMI) undergoing emergent percutaneous coronary intervention (PCI) was estimated. One hundred and twenty-eight patients were randomly divided into control group and observation group with 64 cases in each group. Control group adopted routine blood coagulation indexes, including prothrombin time, activated partial thromboplastin time, fibrinogen and plasma thrombin time, platelet count and platelet aggregation turbidity analysis; observation group adopted Sonoclot detection technology, including activated clotting time, coagulation rate and platelet function. Anticoagulant therapy selected was of low molecular weight heparin calcium perioperatively, intraoperative unfractionated heparin, and clopidogrel (75 mg) combined with aspirin enteric-coated tablets (100 mg) as antiplatelet drugs. The therapy was administered in accordance with blood coagulation results. The blood coagulation time, postoperative creatine kinase isoenzyme MB, cardiac troponin I and B-type natriuretic peptide levels in the observation group are significantly lower than those in the control group (P<0.05) though the operating time and specifications of the stenting did not show any significant difference (P>0.05). The incidence of recurrent myocardial infarction, microembolism, acute and subacute thrombosis and bleeding events in the observation group are significantly lower than those in the control group (P<0.05). In the control group, there is no difference in the coagulation indexes of the patients with thrombosis events or bleeding events or no event (P>0.05). Whereas, in the observation group, there is significant difference in coagulation indexes of the patients with thrombosis events or bleeding events or no event (P<0.05). In conclusion, Sonoclot detection technology instructs emergent PCI treatment in AMI patients to shorten the detection time of blood coagulation, reduce the degree of myocardial injury, reduce the incidence of perioperative thrombosis and bleeding events. Furthermore, it has great value in guiding the clinical medication of anticoagulation and antiplatelet therapy.