Characterization of phospholipid-cholesterol bilayers as self-assembled amphiphile block polymers that contain headgroups.

Cholesterol is known to modulate the structure and function of biological membranes. In this study, we use self-consistent field theory (SCFT) to investigate phospholipid/cholesterol bilayer membranes modeled with two types of diblock copolymers. These copolymer-based bilayers serve as biomimetic platforms with applications in areas such as drug delivery.

Curvature expansion method for polymer self-assembled membranes.

Polymer vesicles consist of a thin bilayer membrane, the shape of which can be precisely controlled by adjusting the composition of block copolymers. These self-assembled structures provide a powerful method for mimicking biological cell membranes. A key characteristic of these membranes is their elastic moduli, which play a crucial role in determining their mechanical properties.

Neural networks trained by weight permutation are universal approximators.

The universal approximation property is fundamental to the success of neural networks, and has traditionally been achieved by training networks without any constraints on their parameters. However, recent experimental research proposed a novel permutation-based training method, which exhibited a desired classification performance without modifying the exact weight values. In this paper, we provide a theoretical guarantee of this permutation training method by proving its ability to guide a ReLU network to approximate one-dimensional continuous functions.

Mimicking effects of cholesterol in lipid bilayer membranes by self-assembled amphiphilic block copolymers.

The effect of cholesterol on biological membranes is important in biochemistry. In this study, a polymer system is used to simulate the consequences of varying cholesterol content in membranes. The system consists of an AB-diblock copolymer, a hydrophilic homopolymer hA, and a hydrophobic rigid homopolymer C, corresponding to phospholipid, water, and cholesterol, respectively.

Tilt Modulus of Bilayer Membranes Self-Assembled from Rod-Coil Diblock Copolymers.

Quantitatively understanding membrane fission and fusion requires a mathematical model taking their underlying elastic degrees of freedom, such as the molecule's tilt, into account. Hamm-Kozlov's model is such a framework that includes a tilt modulus along with the bending modulus and Gaussian modulus. This paper investigates the tilt modulus of liquid-crystalline bilayer membranes by applying self-consistent field theory.

Analytical Calculation of the Elastic Moduli of Self-Assembled Liquid-Crystalline Bilayer Membranes.

Liquid-crystalline orders are ubiquitous in membranes and could significantly affect the elastic properties of the self-assembled bilayers. Calculating the free energy of bilayer membranes with different geometries and fitting them to their theoretical expressions allow us to extract the elastic moduli, such as the bending modulus and Gaussian modulus. However, this procedure is time-consuming for liquid-crystalline bilayers.

Elastic properties of self-assembled bilayer membranes: Analytic expressions via asymptotic expansion.

Bilayer membranes self-assembled from amphiphilic molecules are ubiquitous in biological and soft matter systems. The elastic properties of bilayer membranes are essential in determining the shape and structure of bilayers. A novel method to calculate the elastic moduli of the self-assembled bilayers within the framework of the self-consistent field theory is developed based on an asymptotic expansion of the order parameters in terms of the bilayer curvature.

Elastic properties of liquid-crystalline bilayers self-assembled from semiflexible-flexible diblock copolymers.

The mechanical response and shape of self-assembled bilayer membranes depend crucially on their elastic properties. Most of the studies focused on the elastic properties of fluid membranes, despite the ubiquitous presence of membranes with liquid-crystalline order. Here the elastic properties of liquid-crystalline bilayers self-assembled from diblock copolymers composed of a semiflexible block are studied theoretically.

MNAT1 is overexpressed in colorectal cancer and mediates p53 ubiquitin-degradation to promote colorectal cancer malignance.

Background: MNAT1 (menage a trois 1, MAT1), a cyclin-dependent kinase-activating kinase (CAK) complex, high expresses in various cancers and is involved in cancer pathogenesis. However, mechanisms underlying its regulation in carcinogenesis are unclear.

Methods: The tissue microarray of colorectal cancer (CRC) was used to evaluate MNAT1 expressions in CRC tissues using immunohistochemistry, CRC cell lines were also detected MNAT1 expression using Western-blotting.

Nucleic acid aptamer application in diagnosis and therapy of colorectal cancer based on cell-SELEX technology.

Nucleic acid aptamers are a class of high-affinity nucleic acid ligands. They serve as "chemical antibodies" since their high affinity and specificity. Nucleic acid aptamers are generated from nucleic acid random-sequence using a systematic evolution of ligands by exponential enrichment (SELEX) technology.

Overexpression of MICAL2, a novel tumor-promoting factor, accelerates tumor progression through regulating cell proliferation and EMT.

Molecule interacting with CasL 2 (MICAL2), a microtubule associated monooxygenase, is involved in cell growth, axon guidance, vesicle trafficking and apoptosis. Recent studies have demonstrated that MICAL2 is highly expressed in tumor and accelerates tumor progression and it is deemed to be a novel tumor-promoting factor. MICAL2 overexpression increases cell proliferation to accelerate tumor growth, and MICAL2 also promotes epithelial-mesenchymal transition (EMT)-related proteins to increase cancer cell metastasis.

Liquid crystalline bilayers self-assembled from rod-coil diblock copolymers.

The structure and phase behaviour of bilayer membranes self-assembled from rod-coil diblock copolymers are studied using the self-consistent field theory, focusing on the occurrence and relative stability of liquid crystalline phases induced by the geometric shape and orientational interaction of the rod-blocks. A variety of liquid crystalline bilayers, corresponding to the smectic phases in bulk systems, are predicted to occur as equilibrium phases of the system. The ordered morphologies and phase behaviour of the system are analyzed.

Largely different contents of terpenoids in beef red-flesh tangerine and its wild type.

Background: Niurouhong (Citrus reticulata Blanco. Niurouhong) (NRH) is a spontaneous beef-red flesh mutant with distinctive flavor compared with its wild type orange-red flesh Zhuhongju (ZHJ). To illustrate the biochemical mechanism of its special flesh color and flavor, fruits at commercial mature stage were used to profile the volatiles in the flavedo and determine the levels of carotenoids, limonoid aglycones and phytohormones in the juice sacs in two seasons.

Digital Anatomical Measurement for Anterolateral Fixation of Middle and Lower Thoracic Vertebrae.

Unlabelled: BACKGROUND The key to its successful application is to determine the best entry point for the vertebral screw(s). This study aimed to provide a reference for clinical anterolateral fixation through digital measurement of computed tomography (CT) data to identify relevant anatomical positions in the middle and lower thoracic vertebrae (T4-T12) of 30 adults. MATERIAL AND METHODS We performed digital measurement of anatomical positions in the middle and lower thoracic vertebrae (T4-T12) of 30 adults.

Experimental Application of Bone Marrow Mesenchymal Stem Cells for the Repair of Intervertebral Disc Annulus Fibrosus.

BACKGROUND This study provides experimental results on the applicability of bone marrow mesenchymal stem cells (BMSCs) for the repair of intervertebral disc annulus fibrosus in rabbits. MATERIAL AND METHODS Thirty healthy rabbits were randomized into an observation group (n=15) and a control group (n=15). Both groups underwent degeneration of intervertebral disc annulus fibrosus.

Isolation and characterization of a catalase gene "HuCAT3" from pitaya (Hylocereus undatus) and its expression under abiotic stress.

Abiotic stresses usually cause H2O2 accumulation, with harmful effects, in plants. Catalase may play a key protective role in plant cells by detoxifying this excess H2O2. Pitaya (Hylocereus undatus) shows broad ecological adaptation due to its high tolerance to abiotic stresses, e.

Synthesis and biological evaluation of novel 6-chloro-quinazolin derivatives as potential antitumor agents.

Series of novel derivatives of 6-chloro-quinazolin, which this moiety was linked to a 1,5-diaryl-1,4-pentadien-3-one system, have been synthesized and tested for their antitumor activities in vitro against a panel of three human cancer cell lines (MGC-803, Bcap-37, and PC3 cells). Bioassay results indicated that most of the prepared compounds demonstrated good activities against various cancer cells. 6-chloro-quinazolin derivatives 5a and 5f were the most active members in this study, and experimental results of fluorescent staining and flow cytometry analysis revealed that they could induce apoptosis in MGC-803 and Bcap-37 cells, with apoptosis ratios of 31.

Chemical composition and in vitro evaluation of the cytotoxic and antioxidant activities of supercritical carbon dioxide extracts of pitaya (dragon fruit) peel.

Background: Hylocereus polyrhizus and Hylocereus undatus are two varieties of the commonly called pitaya fruits, and pitaya fruits have gained popularity in many countries all over the world. However, studies on chemical composition and the nutritional quality of pitaya flesh peel are limited.

Results: Extracts of pitaya (H.