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Abstract Background Cancer cells often exhibit large‐scale genomic variations, such as circular extrachromosomal DNA (ecDNA) and structural variants (SVs), which have been highly correlated with the initiation and progression of cancer. Currently, no adequate method exists to unveil how these variations regulate gene expression in heterogeneous cancer cell populations at a single‐cell resolution. Methods Here, we developed a single‐cell multi‐omics sequencing method, scGTP‐seq, to analyse ecDNA and SVs using long‐read sequencing technologies. Results and Conclusions We demonstrated that our method can efficiently detect ecDNA and SVs and illustrated how these variations affect transcriptomic changes in various cell lines. Finally, we applied and validated this method in a clinical sample of hepatocellular carcinoma (HCC), demonstrating a feasible way to monitor the evolution of ecDNA and SVs during cancer progression.

Acetylcholine (ACh) is one of the most important neurotransmitters in the central cholinergic system; it specifically binds to muscarinic and nicotinic receptors and is degraded by acetylcholinesterase (AChE). ACh plays a crucial role in learning and memory. It is generally believed that, in the central nervous system, ACh promotes the conduction of brain nerves and accelerates information transmission. Besides, increasing central ACh levels can enhance memory ability and comprehensively improve brain function. Thus, AChE inhibitors (AChEI), which inhibit the degradation of ACh by AChE, have been used to treat Alzheimer's disease (AD) and Parkinson's disease dementia (PDD). However, recent studies have shown that excessive ACh in the central nervous system impairs learning and memory. Here we review the roles of ACh in learning and memory; we focus on the adverse effects of excessive ACh, the possible mechanisms, and the bidirectional role of ACh in the pathology and cure of AD and PDD. We conclude that the timing and dose of ACh administration should be carefully prescreened when using it to alleviate learning and memory in dementia patients.

Abstract Background Quantum dot (QD)-based single virus tracking has become a powerful tool for dissecting virus infection mechanism. However, only virus behaviors at the early stage of retrograde trafficking have been dynamically tracked so far. Monitoring of comprehensive virus retrograde transportation remains a challenge. Results Based on the superior fluorescence properties of QDs and their labeling of virus internal component, the dynamic interactions between baculoviruses and all key transportation-related cellular structures, including vesicles, acidic endosomes, actins, nuclear pores and nuclei, were visualized at the single-virus level. Detailed scenarios and dynamic information were provided for these critical interaction processes. Conclusions A comprehensive model of baculovirus retrograde trafficking involving virus endocytosis, fusion with acidic endosome, translocation to nuclear periphery, internalization into nucleus, and arriving at the destination in nucleus was proposed. Thus the whole retrograde transportation of baculovirus in live host cells was elucidated at the single-virus level for the first time.

The objective of this study was to evaluate whether RSV inhibits neutrophil extracellular traps (NETs) that induce joint hyperalgesia in C57BL/6 mice after adjuvant-induced arthritis. A subplantar injection of Freund's complete adjuvant was administered to C57BL/6 mice on day 0 for immunization in the AIA model. Resveratrol (RSV, 25 mg/kg) was administered intraperitoneally once daily starting on day 22 and continuing for two weeks. The effects of mechanical hyperalgesia and edema formation have been assessed in addition to histopathological scoring. Mice were sacrificed on day 35 to determine cytokine levels and PADI4 and COX-2 expression levels. ELISA was used to quantify neutrophil extracellular traps (NETs) along with neutrophil elastase-DNA and myeloperoxidase-DNA complexes in neutrophils. An immunohistochemical stain was performed on knee joints to determine the presence of nuclear factor kappa B p65 (NF-κB p65). AIA mice were found to have higher levels of NET in joints and their joint cells demonstrated an increased expression of the PADI4 gene. Treatment with RSV in AIA mice (25 mg/kg, i.p.) significantly (P<0.05) inhibited joint hyperalgesia, resulting in a significant increase in mechanical threshold, a decrease in articular edema, a decrease in the production of inflammatory cytokines, increased COX-2 expression, and a decrease in the immunostaining of NF-κB. Furthermore, treatment with RSV significantly reduced the amount of neutrophil elastase (NE)-DNA and MPO-DNA complexes, which were used as indicators of NET formation (P<0.05). This study indicates that RSV reduces NET production and hyperalgesia by reducing inflammation mediated by PADI4 and COX-2. According to these data, NETs contribute to joint pain and resveratrol can be used to treat pain in RA through this pathway. [ABSTRACT FROM AUTHOR]

The relationship between the two lowpass filters and two highpass filters corresponding to the orthogonal multiwavelets is studied when the two lowpass filters are flipped. An important factor for designing good lowpass and highpass multifilters namely the smoothness of the P-shifted scaling function vectors and multiwavelets is investigated.

A Householder transformation, or Householder reflection, or Household matrix, is a reflection about a hyperplane with a unit normal vector. Not only have the Household matrices been used in QR decomposition efficiently but also implicitly and successfully applied in other areas. In the process of investigating a family of unitary filterbanks, a new family of Householder matrices are established. These matrices are produced when a matrix filter is required to preserve certain order of 2d digital polynomial signals. Naturally, they can be applied to image and signal processing among others. [ABSTRACT FROM AUTHOR]

Purpose: To explore the influence of S100 calcium binding protein A4 (S100A4) knockout (KO) on methionine-choline-deficient (MCD) diet-induced non-alcoholic fatty liver disease (NAFLD) in mice. Materials and Methods: S100A4 KO mice (n=20) and their wild-type (WT) counterparts (n=20) were randomly divided into KO/ MCD, Ko/methionine-choline-sufficient (MCS), WT/MCD, and WT/MCS groups. After 8 weeks of feeding, blood lipid and liver function-related indexes were measured. HE, Oil Red O, and Masson stainings were used to observe the changes of liver histopathology. Additionally, expressions of S100A4 and proinflammatory and profibrogenic cytokines were detected by qRT-PCR and Western blot, while hepatocyte apoptosis was revealed by TUNEL staining. Results: Serum levels of aminotransferase, aspartate aminotransferase, triglyceride, and total cholesterol in mice were increased after 8-week MCD feeding, and hepatocytes performed varying balloon-like changes with increased inflammatory cell infiltration and collagen fibers; however, these effects were improved in mice of KO/MCD group. Meanwhile, total NAFLD activity scores and fibrosis were lower compared to WT+MCD group. Compared to WT/MCS group, S100A4 expression in liver tissue of WT/ MCD group was enhanced. The expression of proinflammatory (TNF-α, IL-1β, IL-6) and profibrogenic cytokines (TGF-β1, COL1A1, α-SMA) in MCD-induced NAFLD mice were increased, as well as apoptotic index (AI). For MCD group, the expressions of proinflammatory and profibrogenic cytokines and AI in KO mice were lower than those of WT mice. Conclusion: S100A4 was detected to be upregulated in NAFLD, while S100A4 KO alleviated liver fibrosis and inflammation, in addition to inhibiting hepatocyte apoptosis. [ABSTRACT FROM AUTHOR]

With the aid of the single-virus tracking technique and the quantum dot-labeling strategy, the internalization of the pseudorabies virus (PrV) has been visualized in real time. The results demonstrate that macropinocytosis can be considered as a major pathway for PrV entering HeLa cells, which facilitates the development of therapeutics for virus-triggered diseases. [ABSTRACT FROM AUTHOR]

Recently, a family of perfect reconstruction (PR) quadrature mirror filterbanks (QMF) with finite impulse response filters (FIR) from systems of biorthogonal refinable functions and wavelets were introduced and also applied to image processing. However, a detailed procedure was absent. The main objective of this paper is to present extensive examples that will provide a thorough process of construction of the new family of PR QMF with FIR filterbanks. These new filters are linearphase due to the symmetry property of their corresponding biorthogonal refinable functions and wavelets. In addition, these filters have odd lengths so that the symmetric extension can be easily applied. Another important feature is that the filters preserve energy (EP) very well. The notion of Condition EP was thus introduced for the purpose of further examining these features. [ABSTRACT FROM AUTHOR]

Implementation of new biorthogonal filter banks (BFB) for image compression and denoising is performed, using test images with diversified characteristics. These new BFB’s are linear-phase, have odd lengths, and with a critical feature, namely, the filters preserve signal energy very well. Experimental results show that the proposed filter banks demonstrate promising performance improvement over the filter banks of those widely used in the image processing area, such as the CDF 9/7. [ABSTRACT FROM AUTHOR]

A 4-point nonlinear corner-cutting subdivision scheme is established. It is induced from a special C-shaped biarc circular spline structure. The scheme is circular-invariant and can be effectively applied to 2-dimensional (2D) data sets that are locally convex. The scheme is also extended adaptively to non-convex data. Explicit examples are demonstrated. [ABSTRACT FROM AUTHOR]

It is always a challenge to effectively teach fundamental math courses to entry level freshmen, and in fact, to high level undergraduate students as well. On one hand, some students' high school math learning habits are not adequate for college; on the other hand, some students were mathematically under-prepared. Although there have been numerous experiments and studies during the past two decades on improving the efficiency of math teaching, we believe that the virtual reality learning environment is a better tool to engage students in a fun math-learning experience. The proposed system possesses unique power that traditional or conventional classroom teaching does not provide, including but not limited to: (1) helping students understand complex, abstract, and non-intuitive concepts and systems; (2) enhancing instruction by making the learning experience game-like, while still retaining the underlying content; and (3) enabling instructors to create a better learning environment for those students having difficulty in learning from the traditional classroom setting. This paper introduces the proposed VRMathLab system, which opens a new door for improving undergraduate math teaching methods as well as learning, and can be used in a wide range of possible ways, such as through individual laptops, labs, and servers for distance learning. [ABSTRACT FROM AUTHOR]

The article discusses two new interpolation subdivision schemes, namely the twin-butterfly scheme that extends existing schemes to achieve C2 continuity and the adaptive scheme that integrates the major existing subdivision schemes and generate the smoothest surface based on the given mesh in any topology. It cites the Subdivision Platform as a new experimental system that tested the two schemes. It concludes that both schemes are attractive and suitable in constructing multiresolution representation of surfaces.

Hexagonal GaN epilayer grown on sapphire substrate by metal organic chemical vapour deposition (MOCVD) is studied using Raman scattering and photoluminescence in a temperature range from 100 K to 873 K. The model of strain (stress) induced by the different lattice parameters and thermal coefficients of epilayer and substrate as a function of temperature is set up. The frequency and the linewidth of E2high mode in a GaN layer are modelled by a theory with considering the thermal expansion of the lattice, a symmetric decay of the optical phonons, and the strain (stress) in the layer. The temperature-dependent energy shift of free exciton A is determined by using Varshni empirical relation, and the effect of strain (stress) is also investigated. We find that the strain in the film leads to a decreasing shift of the phonon frequency and an about 10meV-increasing shift of the energy in a temperature range from 100 K to 823 K. [ABSTRACT FROM AUTHOR]

An iterative scheme for constructing compactly supported orthonormal (o.n.) multi-wavelets with vanishing moments of arbitrarily high order is established. Precisely, let φ=[φ1,. . .,φr]⊤ be an r-dimensional o.n. scaling function vector with polynomial preservation of order (p.p.o.) m, and ψ=[ψ1,. . .,ψr]⊤ an o.n. multi-wavelet corresponding to φ, with two-scale symbols P and Q, respectively. Then a new (r+1)-dimensional o.n. scaling function vector φ♯:=[φ⊤,φr+1]⊤ and some corresponding o.n. multi-wavelet ψ♯ are constructed in such a way that φ♯ has p.p.o.=n>m and their two-scale symbols P♯ and Q♯ are lower and upper triangular block matrices, respectively, without increasing the size of the supports. For instance, for r=1, if we consider the mth order Daubechies o.n. scaling function φ [ABSTRACT FROM AUTHOR]

The notion of armlets is introduced in this letter as a precise formulation of orthonormal multiwavelets that guarantee wavelet decomposition with highpass output not being effected by polynomial perturbation of the input. A mathematical scheme for constructing armlets is given, and it is shown that the notions of armlets and balanced multiwavelets are different. In particular, while balanced wavelets are armlets, the converse is false in general. One advantage of armlets is that the weaker assumption provides flexibility to facilitate wavelet and filter construction. [ABSTRACT FROM AUTHOR]

In a recent work, Selesnick constructed two GHM-like scaling function vectors of dimension two that allow balanced multiwavelet decomposition. In this letter, we construct such multiwavelets and give the corresponding decomposition/reconstruction filters. Symmetry and/or antisymmetry are achieved and filterbank shifts are investigated. The fundamental tools for the study of this problem area are presented in the second and third sections for completeness. [ABSTRACT FROM AUTHOR]

Abstract: Based on metabolic mechanism of scutellarin in vivo that scutellarin could be hydrolyzed into scutellarein by β-glucuronide enzyme, some glucose-containing scutellarein derivatives were designed and synthesized through the introduction of glucose moiety at C-7 position of scutellarein via a glucosidic bond. Biological activity evaluation showed that these glucose-containing scutellarein derivatives exhibited potent DPPH radical scavenging activities. Furthermore, the improvement of physicochemical properties such as anticoagulant and neuroprotective activities alongside with the water solubility was achieved by introducing glucose. These findings suggest that the introduction of the glucose moiety to scutellarein wattants further development of this kind of compounds as neuroprotective agents. [Copyright &y& Elsevier]