Wide Range of Molecular Weight Distribution of Mitogenic Substance(s) in the Hot Water Extract of a Chinese Herbal Medicine, Bupleurum chinense.

MicroRNAs, small non-coding RNA molecules, have gained a reputation of the most substantial regulators in gene network with the ability to down-regulate their targets. Accumulating evidence shifted insight toward microRNAs regulation as the key element of cancer initiation, development, and aggression. Recent studies have attached the importance of traditional Chinese medicine (TCM) to the treatment of various cancers, and the functional natural compounds have been considered as novel anticancer agents to directly inhibit tumor progression. In more recent decades, a wide range of biologically active components of TCM has gained increasing attention to their applications in the modulation of microRNAs. This review is on the purpose of demonstrating the significance of TCM bioactive ingredients in microRNAs regulation for cancer treatment according to the reports mainly in the recent six years, providing the evidence of efficient Chinese herbal medicine-based therapy and effective pro-diagnosis focusing on microRNAs expression of cancer patients.

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Rubber Hydrocarbon in Freshly Tapped Latex

Rubber Chemistry and Technology ◽

10.5254/1.3543536 ◽

1954 ◽

Vol 27 (4) ◽

pp. 1061-1067 ◽

Cited By ~ 2

Author(s):

G. F. Bloomfield

Keyword(s):

Molecular Weight ◽

Molecular Weight Distribution ◽

Weight Distribution ◽

Molecular Weight Range ◽

Considerable Heterogeneity ◽

Weight Range ◽

Molecular Material ◽

Wide Range ◽

Soluble Fractions

Abstract Investigations carried out in Malaya have shown that rubber hydrocarbon in fresh latex is already a high molecular material but of considerable heterogeneity. Latex is separable into non-rubber constituents and rubber hydrocarbon, which is itself separable into microgel, soluble fractions covering a wide range of molecular weight, and low-molecular oxygenated fractions. The molecular weight distribution of the soluble hydrocarbon material is weighted heavily in the higher molecular weight range of half million to five million, with an average around one million. Coagulated rubber contains macrogel in addition to the microgel component of the latex. The microgel component of latex hydrocarbon has been used as a “marker” to indicate from what regions of a tree rubber is withdrawn on tapping.

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Preparation of Quaternary Amphiphilic Block Copolymer PMA-b-P (NVP/MAH/St) and Its Application in Surface Modification of Aluminum Nitride Powders

Molecules ◽

10.3390/molecules26195884 ◽

2021 ◽

Vol 26 (19) ◽

pp. 5884

Author(s):

Yu Wang ◽

Guangdong Zhu ◽

Shun Wang ◽

Jianjun Xie ◽

Zhan Chen ◽

...

Keyword(s):

Molecular Weight ◽

Block Copolymer ◽

Aluminum Nitride ◽

Molecular Weight Distribution ◽

Weight Distribution ◽

Hot Water ◽

Amphiphilic Block Copolymer ◽

Vinyl Pyrrolidone ◽

Charge Transfer Complexes ◽

Nuclear Magnetic Spectroscopy

Poly(methyl acrylate)-b-poly(N-vinyl pyrrolidone/maleic anhydride/styrene) (PMA-b-P (NVP/MAH/St)) quaternary amphiphilic block copolymer prepared by reversible addition-fragmentation chain transfer (RAFT) was used to improve the anti-hydrolysis and dispersion properties of aluminum nitride (AIN) powders that were modified by copolymers. Its structure was characterized by Fourier transform infrared spectroscopy (FT-IR) and Hydrogen nuclear magnetic spectroscopy (1H-NMR). The results demonstrate that the molecular weight distribution of the quaternary amphiphilic block copolymers is 1.35–1.60, which is characteristic of controlled molecular weight and narrow molecular weight distribution. Through charge transfer complexes, NVP/MAH/St produces a regular alternating arrangement structure. After being treated with micro-crosslinking, AlN powder modified by copolymer PMA-b-P(NVP/MAH/St) exhibits outstanding resistance to hydrolysis and can be stabilized in hot water at 50 °C for more than 14 h, and the agglomeration of powder particles was improved remarkably.

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Research on Determination for Food-Related Polystyrene Doped with Recycled Plastic by GPC

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1033-1034.954 ◽

2014 ◽

Vol 1033-1034 ◽

pp. 954-957

Author(s):

Xiao Lei Zhang ◽

Lei Wang ◽

Xiao Qi Chen ◽

Hai Jun Zhou ◽

Shu Lan Yang ◽

...

Keyword(s):

Molecular Weight ◽

Molecular Weight Distribution ◽

Weight Distribution ◽

Food Packaging ◽

Gel Permeation Chromatography ◽

Cumulative Distribution ◽

Mechanical Recycling ◽

Wide Range ◽

Gel Permeation ◽

Physical Degradation

Polystyrene (PS) had wide range of applications in food packaging field. Mechanical recycling of PS was simulated by multiple extrusions to assess the behavior of physical degradation. The molecular weight and the molecular weight distribution of PS with different extrusion cycles were investigated by gel permeation chromatography (GPC). Experimental results show that the differential and cumulative distribution curves of PS shift to smaller values with the number of extrusions cycled increasing. The Mn and Mw of PS decrease. However, Polydispersity index (PDI) increases obviously.

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Preparation and Physicochemical Properties of Concrete Slump-Loss Resistance Agent for Small Slump

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.168-170.2158 ◽

2010 ◽

Vol 168-170 ◽

pp. 2158-2164

Author(s):

Guo Rong Duan ◽

Guo Hong Huang ◽

Xin Wang ◽

Ying Gong

Keyword(s):

Molecular Weight ◽

Physicochemical Properties ◽

Molecular Weight Distribution ◽

Cement Paste ◽

Weight Distribution ◽

Synthesis Method ◽

Retention Performance ◽

Wide Range ◽

Loss Resistance ◽

Gel Permeation

By the application of esterification-polymerization two-step synthesis method, comb-shaped polycarboxylate slump-loss resistance agent XBT for small slump concrete is prepared by controlling ester ratio. The experimental results of concrete and fresh cement paste indicate that XBT has excellent function of plasticity retention in small slump concrete. The experiment of gel permeation liquid chromatogram shows that XBT has wide range of molecular weight distribution, which may be the source of fine plasticity retention performance in the small slump concrete. The combined experiment between ultraviolet and conductivity indicates that there is strong adsorptive action between XBT and Ca2+, and their adsorptive characteristics may be closely related to the plasticity retention properties.

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Study on Multiple Pesticides by High Performance Liquid Chromatography-Mass Spectrometry Using Modified QuEChERS Method - a Case Study on CHM

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.361-363.1752 ◽

2011 ◽

Vol 361-363 ◽

pp. 1752-1755

Author(s):

Yi Wei Dong ◽

Wei Bai ◽

Yu Zhong Li ◽

Chun Ying Xu ◽

Fu Li Fang ◽

...

Keyword(s):

Mass Spectrometry ◽

High Performance Liquid Chromatography ◽

Liquid Chromatography ◽

Herbal Medicine ◽

Chinese Herbal Medicine ◽

High Performance ◽

Liquid Chromatography Mass Spectrometry ◽

Chinese Herbal ◽

Chromatography Mass Spectrometry ◽

Wide Range

QuEChERS is an acetonitrile partitioning and dispersive solid-phase extraction (D-SPE) method that widely used in the analysis of multiple classes of pesticide residues in vegetable and fruit. In this paper, we modified it to fulfill analysis on much more complex matrix-Chinese herbal medicine, and High Performance Liquid Chromatography-Mass Spectrometry (HPLC-MS) was chosen for analysis. This method could be applied to quantitative and qualitative analysis of a wide range of pesticides in Chinese herbal medicine (Fructus Aurantii Immaturus as sample).

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