RNA-seq analysis reveals transcriptome reprogramming and alternative splicing during early response to salt stress in tomato root.

Salt stress is one of the dominant abiotic stress conditions that cause severe damage to plant growth and, in turn, limiting crop productivity. It is therefore crucial to understand the molecular mechanism underlying plant root responses to high salinity as such knowledge will aid in efforts to develop salt-tolerant crops. Alternative splicing (AS) of precursor RNA is one of the important RNA processing steps that regulate gene expression and proteome diversity, and, consequently, many physiological and biochemical processes in plants, including responses to abiotic stresses like salt stress. In the current study, we utilized high-throughput RNA-sequencing to analyze the changes in the transcriptome and characterize AS landscape during the early response of tomato root to salt stress. Under salt stress conditions, 10,588 genes were found to be differentially expressed, including those involved in hormone signaling transduction, amino acid metabolism, and cell cycle regulation. More than 700 transcription factors (TFs), including members of the MYB, bHLH, and WRKY families, potentially regulated tomato root response to salt stress. AS events were found to be greatly enhanced under salt stress, where exon skipping was the most prevalent event. There were 3709 genes identified as differentially alternatively spliced (DAS), the most prominent of which were serine/threonine protein kinase, pentatricopeptide repeat (PPR)-containing protein, E3 ubiquitin-protein ligase. More than 100 DEGs were implicated in splicing and spliceosome assembly, which may regulate salt-responsive AS events in tomato roots. This study uncovers the stimulation of AS during tomato root response to salt stress and provides a valuable resource of salt-responsive genes for future studies to improve tomato salt tolerance.

m6A modification of lncRNA PHKA1-AS1 enhances Actinin Alpha 4 stability and promotes non-small cell lung cancer metastasis.

Cancer is a disease with molecular heterogeneity that is closely related to gene mutations and epigenetic changes. The principal histological subtype of lung cancer is non-small cell lung cancer (NSCLC). Long noncoding RNA (lncRNA) is a kind of RNA that is without protein coding function, playing a critical role in the progression of cancer. In this research, the regulatory mechanisms of lncRNA phosphorylase kinase regulatory subunit alpha 1 antisense RNA 1 (PHKA1-AS1) in the progression of NSCLC were explored. The increased level of N6-methyladenosine (m6A) modification in NSCLC caused the high expression of PHKA1-AS1. Subsequently, high-expressed PHKA1-AS1 significantly facilitated the proliferation and metastasis of NSCLC cells, and these effects could be reversed upon the inhibition of PHKA1-AS1 expression, both in vivo and in vitro. Additionally, the target protein of PHKA1-AS1 was actinin alpha 4 (ACTN4), which is known as an oncogene. Herein, PHKA1-AS1 could enhance the protein stability of ACTN4 by inhibiting its ubiquitination degradation process, thus exerting the function of ACTN4 in promoting the progress of NSCLC. In conclusion, this research provided a theoretical basis for further exploring the potential mechanism of NSCLC metastasis and searching novel biomarkers related to the pathogenesis and progression of NSCLC.

Photosynthetic capacity and assimilate transport of the lower canopy influence maize yield under high planting density.

Photosynthesis is a major trait of interest for development of high-yield crop plants. However, little is known about the effects of high-density planting on photosynthetic responses at the whole-canopy level. Using the high-yielding maize (Zea mays L.) cultivars 'LY66', 'MC670', and 'JK968', we here conducted a two-year field experiment to assess ear development in addition to leaf characteristics and photosynthetic parameters in each canopy layer at four planting densities. Increased planting density promoted high grain yield and population-scale biomass accumulation despite reduced per-plant productivity. MC670 had the strongest adaptability to high-density planting conditions. Physiological analysis showed that increased planting density primarily led to decreases in the single-leaf area above the ear for LY66 and MC670 and below the ear for JK968. Furthermore, high planting density decreased chlorophyll content and the photosynthetic rate due to decreased canopy transmission, leading to severe decreases in single-plant biomass accumulation in the lower canopy. Moreover, increased planting density improved pre-silking biomass transfer, especially in the lower canopy. Yield showed significant positive relationships with photosynthesis and biomass in the lower canopy, demonstrating the important contributions of these leaves to grain yield under dense planting conditions. Increased planting density led to retarded ear development as a consequence of reduced glucose and fructose contents in the ears, indicating reductions in sugar transport that were associated with limited sink organ development, reduced kernel number, and yield loss. Overall, these findings highlighted the photosynthetic capacities of the lower canopy as promising targets for improving maize yield under dense planting conditions.

Jaceosidin inhibits the progression and metastasis of NSCLC by regulating miR-34c-3p/Integrin α2ß1 axis.

Non-coding RNAs are crucial for cancer progression, among which miR-34c-3p has been demonstrated to be a tumor suppressor in non-small cell lung cancer (NSCLC). In this study, we attempt to identify flavonoids that can up-regulate miR-34c-3p expression, evaluate the anticancer activity of the flavonoids and explore its underlying mechanism in NSCLC cells. Six flavonoids were screened by RT-qPCR and we found that jaceosidin significantly increased miR-34c-3p expression in A549 cells. We found that jaceosidin inhibited the proliferation, migration and invasion of A549 and H1975 cells in a dose-relevant manner, indicated by cell counting kit (CCK-8) assay, wound healing assay, transwell assay and EdU assay, we observed that jaceosidin inhibited the proliferation, migration and invasion of A549 and H1975 cells in a dose-relevant manner. Further research suggested that miR-34c-3p bound to the transcriptome of integrin α2ß1 and then inhibited its expression, leading to the inhibitory effect on the migration and invasion of NSCLC. Our study sheds some light on anti-tumor of jaceosidin and provides a potential lead compound for NSCLC therapy.

Effects of microwave ablation on serum Golgi protein 73 in patients with primary liver cancer.

BACKGROUND: Microwave ablation (MWA) is an effective treatment option for patients with primary liver cancer. However, it has been reported that the MWA procedure induces a hepatic inflammatory response and injury, which may negatively affect the efficacy of MWA. As such, the discovery of reliable markers to monitor the patient's response to MWA is needed. Golgi protein 73 (GP73) has been shown to be associated with chronic liver disease. To date, the potential value of serum GP73 in the dynamic monitoring during MWA of liver cancer remains unclear. AIM: To examine the effects of MWA on the serum levels of GP73 in patients with primary liver cancer. METHODS: A total of 150 primary liver cancer patients with a single small lesion (≤ 3 cm in diameter) were retrospectively enrolled spanning the period between January 2016 and October 2018. All of the patients received MWA for the treatment of primary liver cancer. Serum GP73, alpha-fetoprotein (AFP), and widely used liver biochemical indicators [serum albumin, total bilirubin (TBIL), alanine aminotransferase (ALT), and aspartate aminotransferase (AST)] were compared before MWA and at different time points, including 1, 2, and 4 wk following the ablation procedure. RESULTS: Complete tumor ablation was achieved in 95.33% of the patients at 1 mo after MWA. The 1-, 2-, and 3-year disease-free survival rates were 74.67%, 59.33%, and 54.00%, respectively. The serum AFP levels were significantly decreased at 1, 2, and 4 wk after MWA; they returned to the normal range at 12 wk after MWA; and they remained stable thereafter during follow-up in those cases without recurrence. In contrast, the serum GP73 levels were significantly increased at 1 and 2 wk after MWA. The serum GP73 levels reached the peak at 2 wk after MWA, started to decline after hepatoprotective treatment with glycyrrhizin and reduced glutathione, and returned to the pretreatment levels at 12 and 24 wk after MWA. Notably, the changes of serum GP73 in response to MWA were similar to those of TBIL, ALT, and AST. CONCLUSION: Serum GP73 is markedly increased in response to MWA of liver cancer. Thus, serum GP73 holds potential as a marker to monitor MWA-induced inflammatory liver injury in need of amelioration.

Short-term prognostic factors for hepatitis B virus-related acute-on-chronic liver failure.

BACKGROUND: Acute-on-chronic liver failure (ACLF) is the abrupt exacerbation of declined hepatic function in patients with chronic liver disease. AIM: To explore the independent predictors of short-term prognosis in patients with hepatitis B virus (HBV)-related ACLF and to establish a predictive short-term prognosis model for HBV-related ACLF. METHODS: From January 2016 to December 2019, 207 patients with HBV-related ACLF attending the 910th Hospital of Chinese People's Liberation Army were continuously included in this retrospective study. Patients were stratified based on their survival status 3 mo after diagnosis. Information was collected regarding gender and age; coagulation function in terms of prothrombin time and international normalized ratio (INR); hematological profile in terms of neutrophil-to-lymphocyte ratio (NLR) and platelet count (PLT); blood biochemistry in terms of alanine aminotransferase, aspartate aminotransferase, total bilirubin (Tbil), albumin, cholinesterase, blood urea nitrogen (BUN), creatinine, blood glucose, and sodium (Na); tumor markers including alpha-fetoprotein (AFP) and Golgi protein 73 (GP73); virological indicators including HBV-DNA, HBsAg, HBeAg, Anti-HBe, and Anti-HBc; and complications including hepatic encephalopathy, hepatorenal syndrome, spontaneous peritonitis, gastrointestinal bleeding, and pulmonary infection. RESULTS: There were 157 and 50 patients in the survival and death categories, respectively. Univariate analysis revealed significant differences in age, PLT, Tbil, BUN, NLR, HBsAg, AFP, GP73, INR, stage of liver failure, classification of liver failure, and incidence of complications (pulmonary infection, hepatic encephalopathy, spontaneous bacterial peritonitis, and upper gastrointestinal bleeding) between the two groups (P < 0.05). GP73 [hazard ratio (HR): 1.009, 95% confidence interval (CI): 1.005-1.013, P = 0.000], middle stage of liver failure (HR: 5.056, 95%CI: 1.792-14.269, P = 0.002), late stage of liver failure (HR: 22.335, 95%CI: 8.544-58.388, P = 0.000), pulmonary infection (HR: 2.056, 95%CI: 1.145-3.690, P = 0.016), hepatorenal syndrome (HR: 6.847, 95%CI: 1.930-24.291, P = 0.003), and HBsAg (HR: 0.690, 95%CI: 0.524-0.908, P = 0.008) were independent risk factors for short-term prognosis in patients with HBV-related ACLF. Following binary logistics regression analysis, we arrived at the following formula for predicting short-term prognosis: Logit(P) = Ln(P/1-P) = 0.013 × (GP73 ng/mL) + 1.907 × (middle stage of liver failure) + 4.146 × (late stage of liver failure) + 0.734 × (pulmonary infection) + 22.320 × (hepatorenal syndrome) - 0.529 × (HBsAg) - 5.224. The predictive efficacy of the GP73-ACLF score was significantly better than that of the Model for End-Stage Liver Disease (MELD) and MELD-Na score models (P < 0.05). CONCLUSION: The stage of liver failure, presence of GP73, pulmonary infection, hepatorenal syndrome, and HBsAg are independent predictors of short-term prognosis in patients with HBV-related ACLF, and the GP73-ACLF model has good predictive value among these patients.

Study on the CBN Wheel Wear Mechanism of Longitudinal-Torsional Ultrasonic-Assisted Grinding Applied to TC4 Titanium Alloy.

In this study, the CBN (cubic boron nitride) wheel wear model of TC4 titanium alloy in longitudinal-torsional ultrasonic-assisted grinding (LTUAG) was established to explore the grinding wheel wear pattern of TC4 titanium alloy in LTUAG and to improve the grinding efficiency of TC4 titanium alloy and the grinding wheel life. The establishment of the model is based on the grinding force model, the abrasive surface temperature model, the abrasive wear model, and the adhesion wear model of TC4 titanium alloy in LTUAG. The accuracy of the built model is verified by the wheel wear test of TC4 titanium alloy in LTUAG. Research has shown that the grinding force and grinding temperature in LTUAG increase with the increase of the grinding depth and workpiece feed rate and decrease with the increase of the longitudinal ultrasonic amplitude. It also shows that the grinding force gradually decreases with the increase of the grinding wheel speed, while the grinding temperature gradually increases with the increase of the grinding wheel speed. In addition, the use of LTUAG can significantly reduce the wear rate of the grinding wheel by 25.2%. It can also effectively reduce the grinding force and grinding temperature.

RNA-Binding Proteins: The Key Modulator in Stress Granule Formation and Abiotic Stress Response.

To cope with abiotic environmental stress, plants rapidly change their gene expression transcriptionally and post-transcriptionally, the latter by translational suppression of selected proteins and the assembly of cytoplasmic stress granules (SGs) that sequester mRNA transcripts. RNA-binding proteins (RBPs) are the major players in these post-transcriptional processes, which control RNA processing in the nucleus, their export from the nucleus, and overall RNA metabolism in the cytoplasm. Because of their diverse modular domain structures, various RBP types dynamically co-assemble with their targeted RNAs and interacting proteins to form SGs, a process that finely regulates stress-responsive gene expression. This review summarizes recent findings on the involvement of RBPs in adapting plants to various abiotic stresses via modulation of specific gene expression events and SG formation. The relationship of these processes with the stress hormone abscisic acid (ABA) is discussed.

Exosomes of A549 Cells Induced Migration, Invasion, and EMT of BEAS-2B Cells Related to let-7c-5p and miR-181b-5p.

As carriers containing abundant biological information, exosomes could deliver the property of donor cells to recipient cells. Emerging studies have shown that tumor cells could secrete a mass of exosomes into the microenvironment to regulate bystander cells. However, the underlying mechanisms of such a phenomenon remain largely unexplored. In this research, we purified and identified the exosomes of A549 cells and found that A549-cell-derived exosomes promoted BEAS-2B cells migration, invasion, and epithelial-mesenchymal transition (EMT). Importantly, we observed that let-7c-5p and miR-181b-5p were attenuated in A549-cell-derived exosomes compared to BEAS-2B-cell-derived exosomes. The analysis of miRNA expression level in BEAS-2B cells indicated that incubation with A549-cell-derived exosomes reduced the expression levels of let-7c-5p and miR-181b-5p. In transient transfections assay, we found that downregulation of let-7c-5p and miR-181b-5p simultaneously showed stronger promotion of BEAS-2B cells migration and invasion than individually. Moreover, exosomes secreted from A549 cells with upregulated expression of let-7c-5p and miR-181b-5p significantly reduce their regulatory effect on BEAS-2B cells. Bioinformatics analyses revealed that let-7c-5p and miR-181b-5p inhibit the EMT process mainly by regulating focal adhesion and mitogen-activated protein kinase (MAPK) signaling pathway. Thus, our data demonstrated that A549-cell-derived exosomal let-7c-5p and miR-181b-5p could induce migration, invasion, and EMT in BEAS-2B cells, which might be regulated through focal adhesion and MAPK signaling pathway. The expression level of let-7c-5p and miR-181b-5p may show great significance for the early diagnosis of lung cancer.

[Plasma metabolomics in a deep vein thrombosis rat model based on ultra-high performance liquid chromatography-electrostatic field orbitrap high resolution mass spectrometry].

Deep vein thrombosis (DVT) is a venous thromboembolic disease characterized by high incidence, mortality, and sequelae. Therefore, the effective prevention of DVT has become a critical public health concern. However, due to its complexity, the pathophysiological mechanism of DVT remains unclear. Metabolomics can be employed to analyze disease characteristics and provide scientific evidence on the underlying mechanisms. In this study, an established left femoral vein ligation rat model of DVT (n=10) was used and compared with sham surgery controls (n=10). In the DVT group, rats were anesthetized using an intraperitoneal injection of 10% chloral hydrate (300 mg/kg), after which the hair was shaved and the groin disinfected. A 2-cm longitudinal incision was made along the midpoint of the left groin area, and then the left femoral vein was separated. The vein was partially ligated at its proximal end to shrink the blood vessel lumen to approximately half. Then, 0.4 mL of 10% hypertonic saline was slowly injected from the distal end of the left femoral vein. At the same time, the femoral vein turned dark red, which indicated the formation of thrombosis. Finally, the incision was sutured after verifying bleeding in the surrounding tissue. Keeping all other procedures the same as the DVT group, the vein in the control group was not ligated or stimulated using hyper-tonic saline. The abdominal aorta plasma from rats in each group was collected seven days later. Untargeted metabolomics analysis based on ultra-high performance liquid chromatography-electrostatic field orbitrap high resolution mass spectrometry (UHPLC-Orbitrap HRMS) was conducted to investigate the plasma metabolic profiles of the sham surgery control and DVT groups. Principal component analysis (PCA) and orthogonal to partial least squares discrimi-nant analysis (OPLS-DA) on metabolome data for multivariate statistical analysis were employed to assess differences in the metabolic profile between the two groups. The results revealed distinct profiles for the DVT and control groups. The selection criteria for the differential metabolites were the variable importance in the projection (VIP) values of OPLS-DA (VIP>1) and fold changes (FC) in the DVT group (FC≤0.5 or FC≥2, P<0.05). The resulting 27 differential metabolites reflecting a metabolic disorder in the DVT group were selected and analyzed. Of these, the levels of 17 metabolites significantly increased in the DVT group, including trimethylamine N-oxide (TMAO), 4-amino-2-methyl-1-naphthol, chenodeoxycholic acid, and 7-ketocholesterol, whereas the levels of 10 metabolites decreased, including 3-dehydroxycarnitine, phosphatidylcholine 22∶6/20∶2 (PC 22∶6/20∶2), diglyceride 18∶3/20∶4 (DG 18∶3/20∶4) and anserine. To identify the changes in the metabolic pathway reflected by these differential metabolites, a differential abundance (DA) analysis based on the Kyoto Encyclopedia of Genes and Genomes metabolic pathway was conducted. The results showed that the differences in the metabolic pathways between the DVT and control groups were mainly manifested in the primary bile acid biosynthesis, bile secretion, histidine metabolism, linoleic acid metabolism, glycerophospholipid metabolism, and ß-alanine metabolism pathways. Among them, the primary bile acid biosynthesis and bile secretion pathways were upregulated in the DVT group, whereas the glycerophospholipid metabolism, linoleic acid metabolism, and ß-alanine metabolism pathways were downregulated. The histidine metabolism pathway contained upregulated as well as downregulated metabolites, resulting in a DA score of 0. In conclusion, these results indicate that the plasma metabolic profiling of the DVT group was significantly altered, while the disordered metabolites and metabolic pathways could provide a reference to further understand the pathological mechanism of DVT and identify new drug targets.

A transcriptional regulator that boosts grain yields and shortens the growth duration of rice.

Complex biological processes such as plant growth and development are often under the control of transcription factors that regulate the expression of large sets of genes and activate subordinate transcription factors in a cascade-like fashion. Here, by screening candidate photosynthesis-related transcription factors in rice, we identified a DREB (Dehydration Responsive Element Binding) family member, OsDREB1C, in which expression is induced by both light and low nitrogen status. We show that OsDREB1C drives functionally diverse transcriptional programs determining photosynthetic capacity, nitrogen utilization, and flowering time. Field trials with OsDREB1C-overexpressing rice revealed yield increases of 41.3 to 68.3% and, in addition, shortened growth duration, improved nitrogen use efficiency, and promoted efficient resource allocation, thus providing a strategy toward achieving much-needed increases in agricultural productivity.

Research Advances in Genetic Mechanisms of Major Cucumber Diseases Resistance.

Cucumber (Cucumis sativus L.) is an important economic vegetable crop worldwide that is susceptible to various common pathogens, including powdery mildew (PM), downy mildew (DM), and Fusarium wilt (FM). In cucumber breeding programs, identifying disease resistance and related molecular markers is generally a top priority. PM, DM, and FW are the major diseases of cucumber in China that cause severe yield losses and the genetic-based cucumber resistance against these diseases has been developed over the last decade. Still, the molecular mechanisms of cucumber disease resistance remain unclear. In this review, we summarize recent findings on the inheritance, molecular markers, and quantitative trait locus mapping of cucumber PM, DM, and FM resistance. In addition, several candidate genes, such as PM, DM, and FM resistance genes, with or without functional verification are reviewed. The data help to reveal the molecular mechanisms of cucumber disease resistance and provide exciting new opportunities for further resistance breeding.

Effect of lathyrol derivatives on non-small cell lung cancer and the possible mechanism. / 千金子二萜醇衍生物抗非小细胞肺癌的作用及机制.

OBJECTIVES: Non-small cell lung cancer (NSCLC) accounts for 85% of all lung cancer, with highmorbidity and mortality rate. Nove drug development for NSCLC is urgently needed.This study aims to investigate the activity of lathyrol derivatives and the mechanism for its inhibitory effect on the growth of NSCLC cells. METHODS: Three lathyrol derivatives were synthesized from lathyrol and their structures were verified by nuclear magnetic resonance. MTT assay was used to detect the effects of the lathyrol derivatives on the proliferation activity of NSCLC cells (A549 and H1299 cells), and the compound with the best activity was selected for subsequent experiments. Colony forming assay, wound-healing assay, and transwell assay were applied to detect in vitro cell proliferation, migration and invasion ability in A549 and H1299 cells, respectively. Quantitative real-time RT-PCR and Western blotting were performed to detect mRNA and protein levels of E-cadherin, N-cadherin, ß-catenin, and MMP2 in A549 cells, respectively. RESULTS: Three lathyrol derivatives inhibited the growth of A549 and H1299 cells in a dose-dependent manner, and they showed a weak inhibitory effect on normal cells Beas-2B and 16HBE, indicating that they possessed certain selective toxic effects. Therefore, C-5 benzoylated lathyrol with the best activity was selected as the ideal drug for the subsequent experiments. Compared with the control group, the number and size of cell clusters in the treatment group of A549 and H1299 cells were significantly decreased, the relative mobility were significantly decreased, and the number of invaded cells were significantly decreased (all P<0.05), indicating that the in vitro cell proliferation, migration and invasion ability were decreased. The mRNA levels of integrin α2, integrin ß1, MMP2, MMP9, ß-catenin, and N-cadherin were decreased, while the expression of E-cadherin was increased (all P<0.05). The protein levels of N-cadherin, ß-catenin, MMP2, and integrin αV were decreased, while the expression of E-cadherin was increased (all P<0.05). CONCLUSIONS: The lathyrol derivatives synthesized in this study possess good inhibitory activity against NSCLC. Among them, C-5 benzoylated lathyrol significantly inhibits the proliferation, migration, and invasion ability of NSCLC cells in vitro through regulating the process of epithelial-mesenchymal transition.

Cytochrome P450 CYP709C56 metabolizing mesosulfuron-methyl confers herbicide resistance in Alopecurus aequalis.

Multiple herbicide resistance in diverse weed species endowed by enhanced herbicide detoxification or degradation is rapidly growing into a great threat to herbicide sustainability and global food safety. Although metabolic resistance is frequently documented in the economically damaging arable weed species shortawn foxtail (Alopecurus aequalis Sobol.), relevant molecular knowledge has been lacking. Previously, we identified a field population of A. aequalis (R) that had evolved metabolic resistance to the commonly used acetolactate synthase (ALS)-inhibiting herbicide mesosulfuron-methyl. RNA sequencing was used to discover potential herbicide metabolism-related genes, and four cytochrome P450s (CYP709C56, CYP71R18, CYP94C117, and CYP94E14) were identified with higher expressions in the R vs. susceptible (S) plants. Here the full-length P450 complementary DNA transcripts were each cloned with identical sequences between the S and R plants. Transgenic Arabidopsis overexpressing CYP709C56 became resistant to the sulfonylurea herbicide mesosulfuron-methyl and the triazolo-pyrimidine herbicide pyroxsulam. This resistance profile generally but does not completely in accordance with what is evident in the R A. aequalis. Transgenic lines exhibited enhanced capacity for detoxifying mesosulfuron-methyl into O-demethylated metabolite, which is in line with the detection of O-demethylated herbicide metabolite in vitro in transformed yeast. Structural modeling predicted that mesosulfuron-methyl binds to CYP709C56 involving amino acid residues Thr-328, Thr-500, Asn-129, Gln-392, Phe-238, and Phe-242 for achieving O-demethylation. Constitutive expression of CYP709C56 was highly correlated with the metabolic mesosulfuron-methyl resistance in A. aequalis. These results indicate that CYP709C56 degrades mesosulfuron-methyl and its up-regulated expression in A. aequalis confers resistance to mesosulfuron-methyl.

Application of microfluidic chips in anticancer drug screening.

With the continuous development of drug screening technology, new screening methodologies and technologies are constantly emerging, driving drug screening into rapid, efficient and high-throughput development. Microfluidics is a rising star in the development of innovative approaches in drug discovery. In this article, we summarize the recent years' progress of microfluidic chip technology in drug screening, including the developmental history, structural design, and applications in different aspects of microfluidic chips on drug screening. Herein, the existing microfluidic chip screening platforms are summarized from four aspects: chip structure design, sample injection and drive system, cell culture technology on a chip, and efficient remote detection technology. Furthermore, this review discusses the application and developmental prospects of using microfluidic chips in drug screening, particularly in screening natural product anticancer drugs based on chemical properties, pharmacological effects, and drug cytotoxicity.

Study on the Algorithm of Three-Dimensional Surface Residual Material Height of Nano-ZrO2 Ceramics under Ultra-Precision Grinding.

A large number of studies have shown that the height of a residual material is the key factor affecting the surface quality of ultra-precision grinding. However, the grinding process contains several random factors, such as the randomness of grinding particle size and the random distribution of grinding particles, which cause the complexity of the material removal process. In this study, taking the Nano-ZrO2 as an example, the removal process of surface materials in ultra-precision grinding of hard and brittle materials was analyzed by probability. A new calculation method for the height of surface residual materials in ultra-precision grinding of Nano-ZrO2 was proposed, and the prediction model of the three-dimensional roughness Sa and Sq were established by using this calculation method. The simulation and experimental results show that this calculation method can obtain the more accurate surface residual material height value which accords with the characteristics of three-dimensional roughness sampling, which provides a theoretical reference for the analysis of the material removal process and the surface quality evaluation of ultra-precision grinding of hard and brittle materials.

Microfluidics applications for high-throughput single cell sequencing.

The inherent heterogeneity of individual cells in cell populations plays significant roles in disease development and progression, which is critical for disease diagnosis and treatment. Substantial evidences show that the majority of traditional gene profiling methods mask the difference of individual cells. Single cell sequencing can provide data to characterize the inherent heterogeneity of individual cells, and reveal complex and rare cell populations. Different microfluidic technologies have emerged for single cell researches and become the frontiers and hot topics over the past decade. In this review article, we introduce the processes of single cell sequencing, and review the principles of microfluidics for single cell analysis. Also, we discuss the common high-throughput single cell sequencing technologies along with their advantages and disadvantages. Lastly, microfluidics applications in single cell sequencing technology for the diagnosis of cancers and immune system diseases are briefly illustrated.

The Potential Role of Extracellular Vesicles in COVID-19 Treatment: Opportunity and Challenge.

SARS-CoV-2 infection has become an urgent public health concern worldwide, severely affecting our society and economy due to the long incubation time and high prevalence. People spare no effort on the rapid development of vaccine and treatment all over the world. Amongst the numerous ways of tackling this pandemic, some approaches using extracellular vesicles (EVs) are emerging. In this review, we summarize current prevalence and pathogenesis of COVID-19, involving the combination of SARS-CoV-2 and virus receptor ACE2, endothelial dysfunction and micro thrombosis, together with cytokine storm. We also discuss the ongoing EVs-based strategies for the treatment of COVID-19, including mesenchymal stem cell (MSC)-EVs, drug-EVs, vaccine-EVs, platelet-EVs, and others. This manuscript provides the foundation for the development of targeted drugs and vaccines for SARS-CoV-2 infections.