Exosomes are small extracellular vesicles with diameters of 30-150 nm. In both physiological and pathological conditions, nearly all types of cells can release exosomes, which play important roles in ...cell communication and epigenetic regulation by transporting crucial protein and genetic materials such as miRNA, mRNA, and DNA. Consequently, exosome-based disease diagnosis and therapeutic methods have been intensively investigated. However, as in any natural science field, the in-depth investigation of exosomes relies heavily on technological advances. Historically, the two main technical hindrances that have restricted the basic and applied researches of exosomes include, first, how to simplify the extraction and improve the yield of exosomes and, second, how to effectively distinguish exosomes from other extracellular vesicles, especially functional microvesicles. Over the past few decades, although a standardized exosome isolation method has still not become available, a number of techniques have been established through exploration of the biochemical and physicochemical features of exosomes. In this work, by comprehensively analyzing the progresses in exosome separation strategies, we provide a panoramic view of current exosome isolation techniques, providing perspectives toward the development of novel approaches for high-efficient exosome isolation from various types of biological matrices. In addition, from the perspective of exosome-based diagnosis and therapeutics, we emphasize the issue of quantitative exosome and microvesicle separation.
Non-viral vector-mediated transfection is a core technique for in vitro screening of oligonucleotides. Despite the growing interests in the development of oliogonucleotide-based drug molecules in ...recent years, a comprehensive comparison of the transfection efficacy of commonly used commercial transfection reagents has not been reported. In this study, five commonly used transfection reagents, including Lipofectamine 3000, Lipofectamine 2000, Fugene, RNAiMAX and Lipofectin, were comprehensively analyzed in ten cell lines using a fluorescence imaging-based transfection assay. Although the transfection efficacy and toxicity of transfection reagents varied depending on cell types, the toxicity of transfection reagents generally displayed a positive correlation with their transfection efficacy. According to our results, Lipofectamine 3000, Fugene and RNAiMAX showed high transfection efficacy, however, RNAiMAX may be a better option for majority of cells when lower toxicity is desired. The transfection efficacy of Lipofectamine 2000 was compromised by its high toxicity, which may adversely affect its application in most cells. We firmly believe that our findings may contribute to the future In vitro delivery and screening of single-stranded therapeutic oligonucleotides such as antisense oligonucleotides, antimiRs, and DNAzymes.
Advanced high strength steels for the auto industry are in high demand regarding the development of new type of steels, reliable and economic welding techniques, etc. In this study, the third ...generation advanced high strength steels, cold-rolled quenching and partitioning steels (QP980), were butt-welded using fiber laser to evaluate the microstructure, mechanical properties and formability of joint. The fusion zone composed of lath martensite with high microhardness (499 HV). Martensite tempering and carbide precipitation were found at the sub-critical heat affected zone, resulting in a slight decrease of microhardness (~ 37 HV drop). The presence of joint had no effect on tensile strength and all welded samples failed at the base metal with 98.8% joint efficiency. The formability of welded blanks in Erichsen cupping test was dependent on the weld line position. The formability ratio was only 68.08% of base metal when weld line offset was 0mm, and increased as the weld line moving away from the blank center because more deformation was transferred to base metal. Stretch-flange-formability of the joint in hole expanding test was inferior to that of base metal due to the high volume fraction of coarse martensite in fusion zone.
•Filter, wrapper, embedded and ensemble feature selection approaches (FS) were evaluated.•The proposed ensemble FS incorporates ten individual selectors to identify top significant ...variables.•Ensemble FS produced the highest predictive variable subset for mapping SOM.•XGBoost outperformed RF in mapping SOM in subtropical restored forests.
Mapping Soil organic matter (SOM) over a complex forest landscape is challenging due to the difficulty in selecting the most insightful variables from high-dimensional datasets in the recent explosion of geospatial-data. Feature selection (FS) is necessary to reduce data redundancy and noise as well as to achieve more reliable SOM spatial predictions. However, it is still unclear that which is most effective among various FS methods in mapping SOM. Therefore, four types of FS approaches (i.e., filter, wrapper, embedded and ensemble) were adopted to generate optimum variable subsets from an original variable dataset of 60 candidates, respectively, for mapping SOM of restored forest land in a typical subtropical region of southern China. The most used methods for each type of FS approaches were selected in this study, including three filters (Chi-square, InfoGain and pearson correlation analysis), three wrappers (genetic algorithm, simulated annealing algorithm and support vector machine-recursive feature elimination) and three embedded methods (Boruta, random forest (RF) and extreme gradient boosting (XGBoost)), as well as an ensemble method (robust rank aggreg algorithm (RRA)). Meanwhile, the RF and XGBoost models were applied with a 10-fold cross-validation method to compare the relative advantages of the different FS methods in SOM mapping, by utilizing the correlation coefficients R2 between observed and predicted values and predicting errors of root mean square error (RMSE). The results show that the SOM prediction accuracies with optimized variable subsets generated by the different FS methods are better than those with full variables, yet the improvements of prediction performance are different among the four types of FS approaches. The ensemble method (RRA) is superior to the other three types of approaches with an average RMSE reduction of 9.16% comparing to that without using FS methods, followed by wrapper and embedded methods which obtained the average RMSE reduction by 7.81%, 7.32%, respectively, and the filter methods are the weakest in the RMSE reduction with slight decreases of 4.32%. The XGBoost model achieved a better performance in predicting SOM than the RF model regardless of input variables, and the XGBoost model combined with RRA FS method shows the greatest potential to map SOM in the restored forest land. This study provides a reference for obtaining more parsimonious and robust variable sets from the available big geo-data freely for soil mapping in other areas.
In recent decades, China's rapid urbanization has produced numerous economic benefits while simultaneously creating substantial risks to ecological security. China's 14th Five-Year Plan and the ...United Nations Sustainable Development Goals (SDGs) have recently explicitly called for the coordinated development of ecological security and urbanization. Given this context, it is important to explore the mechanism by which ecological security and urbanization are coupled and coordinated to promote sustainable development. In this study, an index of the relationship between ecological security and urbanization was established via high-resolution data, and a "Computation-Verification-Coupling" (CVC) framework was constructed. The accuracy of the ecological security index was verified using a linear regression model, and the coordination level between ecological security and urbanization was analyzed via a coupled coordination model (CCM). The results revealed a steady increase in the ecological security index from 2010 to 2020; the proportion of the area above the medium level increased from 63.1 % to 74.1 %. The urbanization index in core counties exhibited rapid growth, with level V urbanized areas expanding from 5.5 % to 9.9 %. The ecological security verification model produced a coefficient of determination (R²) of 0.75685, indicating a satisfactory degree of predictive capability. From 2010–2020, the coupled coordination improved, with the high coordination area accounting for 48.8 % and the extreme discoordination area decreasing from 1.8 % to 1.0 %. Coordinated development exhibited a stable progression, characterized by a cyclical evolution from initial coupling to antagonistic coupling and finally to coordinated development. This framework can be used not only to investigate the relationship between ecological security and urbanization but also to provide a quantifiable measure of progress toward achieving the SDGs.
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•Using high-resolution data to evaluate ecological security and urbanization index.•Validating the accuracy of ecological security models using linear regression.•Analyzing the spatial pattern and coupling coordination process of ecological security and urbanization on the grid scale.•Constructing a "calculation-verification-coupling" evaluation framework to explore ecological security and urbanization.
High-performance quantum memory for quantized states of light is a prerequisite building block of quantum information technology. Despite great progresses of optical quantum memories based on ...interactions of light and atoms, physical features of these memories still cannot satisfy requirements for applications in practical quantum information systems, since all of them suffer from trade-off between memory efficiency and excess noise. Here, we report a high-performance cavity-enhanced electromagnetically-induced-transparency memory with warm atomic cell in which a scheme of optimizing the spatial and temporal modes based on the time-reversal approach is applied. The memory efficiency up to 67 ± 1% is directly measured and a noise level close to quantum noise limit is simultaneously reached. It has been experimentally demonstrated that the average fidelities for a set of input coherent states with different phases and amplitudes within a Gaussian distribution have exceeded the classical benchmark fidelities. Thus the realized quantum memory platform has been capable of preserving quantized optical states, and is ready to be applied in quantum information systems, such as distributed quantum logic gates and quantum-enhanced atomic magnetometry.
The adverse reactions (ADRs) of targeted therapy were closely associated with treatment response, clinical outcome, quality of life (QoL) of patients with cancer. However, few studies presented the ...correlation between ADRs of targeted therapy and treatment effects among cancer patients. This study was to explore the characteristics of ADRs with targeted therapy and the prognosis of cancer patients based on the clinical data.
A retrospective secondary data analysis was conducted within an ADR data set including 2703 patients with targeted therapy from three Henan medical centers of China between January 2018 and December 2019. The significance was evaluated with chi-square test between groups with or without ADRs. Univariate and multivariate logistic regression with backward stepwise method were applied to assess the difference of pathological characteristics in patients with cancer. Using the univariate Cox regression method, the actuarial probability of overall survival was performed to compare the clinical outcomes between these two groups.
A total of 485 patients were enrolled in this study. Of all patients, 61.0% (n = 296) occurred ADRs including skin damage, fatigue, mucosal damage, hypertension and gastrointestinal discomfort as the top 5 complications during the target therapy. And 62.1% of ADRs were mild to moderate, more than half of the ADRs occurred within one month, 68.6% ADRs lasted more than one month. Older patients (P = 0.022) and patients with lower education level (P = 0.036), more than 2 comorbidities (P = 0.021), longer medication time (P = 0.022), drug combination (P = 0.033) and intravenous administration (P = 0.019) were more likely to have ADRs. Those with ADRs were more likely to stop taking (P = 0.000), change (P = 0.000), adjust (P = 0.000), or not take the medicine on time (P = 0.000). The number of patients with recurrence (P = 0.000) and metastasis (P = 0.006) were statistically significant difference between ADRs and non-ADRs group. And the patients were significantly poor prognosis in ADRs groups compared with non-ADRs group.
The high incidence of ADRs would affect the treatment and prognosis of patients with cancer. We should pay more attention to these ADRs and develop effective management strategies.
Cell differentiation within an isogenic population allows the specialisation of subpopulations and a division of labour. Bacillus thuringiensis is a spore‐forming bacterium that produces insecticidal ...crystal proteins (Cry proteins) in sporulating cells. We recently reported that strain B. thuringiensis LM1212 presents the unique ability to differentiate into two subpopulations during the stationary phase: spore‐formers and crystal‐producers. Here, we characterised the transcriptional regulator CpcR responsible for this differentiation and the expression of the cry genes. cpcR is located on a plasmid that also harbours cry genes. The alignment of LM1212 cry gene promoters revealed the presence of a conserved DNA sequence upstream from the −35 region. This presumed CpcR box was also found in the promoter of cpcR and we showed that cpcR transcription is positively autoregulated. Electrophoretic mobility shift assays suggested that CpcR directly controls the transcription of its target genes by binding to the CpcR box. We showed that CpcR was able to direct the production of a crystal consisting of a heterologous insecticidal Cry protein in non‐sporulating cells of a typical B. thuringiensis kurstaki strain. Moreover, the expression of cpcR induced a reduction in the sporulation of this B. thuringiensis strain, suggesting an interaction between CpcR and the sporulation regulatory networks.
The B. thuringiensis strain LM1212 differentiates into two distinct subpopulations: a population forming spores and another forming non‐viable cells producing crystal inclusions. We have characterised the transcriptional activator, CpcR, responsible for this division of labour. We show that CpcR activates its own expression and the transcription of LM1212 cry genes during the stationary phase. In parallel, CpcR induces a reduction in sporulation.
Accurate separation of photosynthetic and nonphotosynthetic components in a forest canopy from 3-D terrestrial laser scanning (TLS) data is a challenging but of key importance to understand the ...spatial distribution of the radiation regime, photosynthetic processes, and carbon and water exchanges of the forest canopy. The objective of this paper was to improve current methods for separating photosynthetic and nonphotosynthetic components in TLS data of forest canopies by adding two additional filters only based on its geometric information. By comparing the proposed approach with the eigenvalues plus color information-based method, we found that the proposed approach could effectively improve the overall producer's accuracy from 62.12% to 95.45%, and the overall classification producer's accuracy would increase from 84.28% to 97.80% as the forest leaf area index (LAI) decreases from 4.15 to 3.13. In addition, variations in tree species had negligible effects on the final classification accuracy, as shown by the overall producer's accuracy for coniferous (93.09%) and broadleaf (94.96%) trees. To remove quantitatively the effects of the woody materials in a forest canopy for improving TLS-based LAI estimates, we also computed the "woody-to-total area ratio" based on the classified linear class points from an individual tree. Automatic classification of the forest point cloud data set will facilitate the application of TLS on retrieving 3-D forest canopy structural parameters, including LAI and leaf and woody area ratios.
Porcine skeletal muscle is a highly heterogeneous tissue type, and the Longissimus Dorsi muscle (LDM), as the most economical and physiologically metabolized skeletal muscle in pigs, has always been ...the focus of research and improvement in pig molecular breeding. Circular RNA, as an important new member of regulatory non-coding RNA after microRNA, has become a frontier hot spot in life science research. This study aims to explore candidate circRNAs related to growth, meat quality, and skeletal muscle development among Duroc pigs with different average daily gain (ADG). Eight pigs were selected and divided into two groups: H group (high-ADG) and L group (low-ADG), followed by RNA-Seq analysis to identify circRNAs. The results showed that backfat at 6-7 rib (BF) and Intramuscular fat (IMF) content in the H group was significantly lower than L group, but ribeye area (REA) in the H group was higher than in the L group. In RNA-seq, 296 Differentially expressed (DE) circRNAs (157 upregulated and 139 downregulated) were identified and exons flanking long introns are easier to circularize to produce circRNAs. Most of the DE circRNAs were enriched in Quantitative trait locus (QTL) regions related to meat quality and growth traits. In addition, a gene can produce one or more circRNA transcripts. It was also found that the source genes of DE circRNAs were enriched in MAPK, FoXO, mTOR, PI3K-Akt, and Wnt signaling pathways. The results showed that different ADG, carcass, and meat quality traits among half-sibling Duroc pigs with the same diet may be due to the DE circRNAs related to skeletal muscle growth and development.
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