1.Higher brain function as precipitant of seizure.
Neurology Asia 2007;12(1):1-5
An epileptic seizure can be induced by higher brain function or mental processes associated with emotion. The precipitation involves verbal, non-verbal and specific thinking with emotion. Some of these patients have symptomatic and focal epilepsies. Others were idiopathic epilepsies, where the hyperexcitable regions and systems provoked by some specific stimuli may produce epileptic seizures that results in symmetrical, asymmetrical, or even localized clinical manifestations. The understanding of precipitation of seizures by higher brain function may contribute to understanding of epileptogenesis and nosology of epilepsies.
brain function
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Seizures
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Comprehension
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Precipitation
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Epilepsy
2.Advances of enzymes related to microbial cement.
Lei WANG ; Xuxia WANG ; Fei LI ; Mingjuan CUI ; Xiaoxu YANG ; Min YANG ; Yunjun YAN
Chinese Journal of Biotechnology 2022;38(2):506-517
Microbial induced calcium carbonate precipitation (MICP) refers to the natural biological process of calcium carbonate precipitation induced by microbial metabolism in its surrounding environment. Based on the principles of MICP, microbial cement has been developed and has received widespread attention in the field of biology, civil engineering, and environment owing to the merits of environmental friendliness and economic competence. Urease and carbonic anhydrase are the key enzymes closely related to microbial cement. This review summarizes the genes, protein structures, regulatory mechanisms, engineering strains and mutual synergistic relationship of these two enzymes. The application of bioinformatics and synthetic biology is expected to develop biocement with a wide range of environmental adaptability and high performance, and will bring the MICP research to a new height.
Calcium Carbonate/metabolism*
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Chemical Precipitation
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Urease/metabolism*
3.Effective delivery of quality markers in alcohol precipitation of Pudilan Xiaoyan Oral Liquid.
Ran HUANG ; Meng-Hua JIANG ; E SUN ; Chao LI ; Fa-Gen ZHU ; Jian-Guo SHAO ; Liang FENG ; Xiao-Bin JIA
China Journal of Chinese Materia Medica 2022;47(21):5757-5764
Taking Pudilan Xiaoyan Oral Liquid as a demonstration, the effective delivery of quality markers in alcohol precipitation of Chinese medicine oral liquid preparations was studied. With the transfer rates of adenosine, corynoline, cichoric acid, baicalin, and wogonin as evaluation indexes, the effect of the density of concentrate before alcoholic precipitation, volume fraction of ethanol, stirring speed, temperature of concentrated solution, stirring time, alcohol concentration, alcohol precipitation time, alcoholic precipitation temperature, alcohol addition rate, and the pH of concentrate on the alcohol precipitation process was investigated by Plackett-Burman trial design, thus obtaining the key factors that influenced the alcohol precipitation process. The key factors were further optimized by Box-Behnken design to determine the optimal alcohol precipitation conditions. When the density of concentrate before alcoholic precipitation was 1.12 g·mL~(-1), the pH of concentrate was 6.86, and the alcohol concentration was 50.00%, the transfer rates of baicalin and wogonin were 91.86% and 87.78%, respectively. When the density of concentrate before alcoholic precipitation was 1.13 g·mL~(-1), the concentration of alcohol was 74.50%, and the alcoholic precipitation temperature was 17.0 ℃, the transfer rates of adenosine, corynoline, and cichoric acid were 85.95%, 71.62% and 83.19%, respectively. The method of optimizing alcohol precipitation techniques and determining the parameters of Pudilan Xiaoyan Oral Liquid by response surface methodology is reasonable and feasible, which provides guidance and experience for the effective delivery of quality markers in Chinese medicine oral liquid preparations.
Drugs, Chinese Herbal
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Ethanol
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Adenosine
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Chemical Precipitation
4.The synthesis of hydroxyapatite through the precipitation method.
Rizal K Shah ; M N Fahmi ; Akil H Mat ; Arifin A Zainal
The Medical journal of Malaysia 2004;59 Suppl F():75-6
Hydroxyapatite (HA) has been earmarked as suitable for implantation within the human of its chemical makeup to human bone. In this paper, HA powders were synthesized via the precipitation method where phosphoric acid (H3PO4) was titrated into calcium hydroxide solution [Ca(OH)2]. Two parameters such as temperature and stirring rate were identified as factors that influenced the amount and purity of HA powder. Phase identification of the synthesized powder was done using X-Ray Diffraction (XRD). The results show that HA phase can be synthesized from this titration process of Ca(OH)2 and H3PO4 with yield amount of HA powder around 45 - 61 grams but with less than hundred percent purity. In order to study the effect of heat treatment to HA crystals structure, HA powder was calcined at 850 degrees C for 2 hours. It's found that the degree of crystallinity increases after calcination because of lattice expansion when the materials were heated at higher temperature
Sjogren's syndrome B antibody
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Powders
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Durapatite
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Precipitation
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hydroxyl group
5.Applied research into the production process of gama - Globulin from Human Plasma and Standard gama - Globulin with Rich of Anti \u2013 HBs
Phan Trung Do ; Duong Tuan Pham ; Hien Thi Do ; Thuy Thi Tran ; Thin Duy Ngo ; Phuc Hanh Hoang ; Hai Xuan Le ; Tri Anh Nguyen
Journal of Medical Research 2008;0(1):67-71
Introduction: The need for gama \u2013 globulin, especially gama - globulin - anti \u2013 HBs, is huge in Vietnam. A number of patients cannot to afford use them due to the high price as they are imported. Meanwhile, Vietnam has high quality input sources for producing gama \u2013 globulin. \r\n', u'Objectives: To study the production process of gama - Globulin from Human Plasma and Standard gama - Globulin with Rich of Anti \u2013 HBs. \r\n', u'Subjects and method: 168 samples of human plasma from voluntary blood donors, which had been screened with for transfusion transmittable infections (TTLs), were chosen as plasma with rich of anti - HBs. The plasma with anti - HBsAg was precipitated with ethanol 25%, pH 6,9 to gain gama - globulin with rich anti - HBs, which was dried by Dutch Ly - 3 - TTE machine. Activation of anti - HBs gama - globulin was identified by a standard method of the degree of antibody specific for anti - HBsAg kit of BIORAD, \r\n', u'Results: The purity of the gama - globulin achieved was 93%, which was almost equal with the results of some foreign researchers (7.8), the activation of anti - HBs was 1:128 dilution degree. The productivity of gama - globulin gaining from 1 litter plasma was 6.0 gram. This new issue was first demonstrated in Vietnam. \r\n', u'Conclusion: We can domestically produce anti-Bs gama - globulin with high degree of activeness (1:128) from human plasma by the precipitating method with ethanol, pH and low temperature. \r\n', u'
Human plasma
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gama - globulin - anti - HBs
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Precipitation of ethanol
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pH and low temperature
6.Comparative study on two polymerization methods for preparing ginsenoside Rg1 molecularly imprinted polymer separating materials.
Qing-Shan LIU ; Li-Na YI ; Ke-Qin LI ; Xiao-Ying YIN
China Journal of Chinese Materia Medica 2013;38(24):4287-4291
To obtain ginsenoside Rg1 molecularly imprinted polymer (MIP) separating materials with high selectivity, enrichment and adsorption performance through directional separation of ginsenoside Rg1 and analogues. In this study, MIPs were respectively prepared by precipitation polymerization and surface imprinted polymerization. Their adsorption performances were compared. The results showed that ginsenoside Rg1 MIPs prepared by the above two methods had a high adsorption performance to template molecules, with the maximum apparent adsorbing capacity of up to 27.74, 46. 80 mg x g(-1), respectively. Moreover, MIPs prepared by surface imprinted polymerization showed higher adsorption capacity than that by precipitation polymerization. The experimental results indicated that as for ginsenoside Rg1 with higher polarity, MIPs prepared by surface imprinted polymerization showed higher selectivity and adsorption performance, which provides provide important reference for preparing imprinted polymers with good adsorption performance with active molecules with strong polarity.
Adsorption
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Chemical Fractionation
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methods
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Chemical Precipitation
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Ginsenosides
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chemistry
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isolation & purification
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Molecular Imprinting
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Polymerization
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Polymers
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chemical synthesis
7.Stability of the hydrogenase from Tetraselmis subcordiformis and its preliminary purification.
Fei YAN ; Zhao'an CHEN ; Xupeng CAO ; Hongbin LU ; Song XUE ; Wei ZHANG
Chinese Journal of Biotechnology 2010;26(7):1003-1008
Tetraselmis subcordiformis, a marine green alga, can produce hydrogen by photobiologically hydrolyzing seawater with hydrogenase. In this study, the preliminary purification of the enzyme was explored by ammonium sulfate precipitation, and the impact of sodium dithionite, beta-mercaptoethanol and glycerol on the enzyme stability during the process was investigated. The experimental results illustrated that sodium dithionite provided significant protection on the hydrogenase by depleting oxygen, while glycerol, a protectant against the structure instability of the enzyme, also presented protection. Crude enzyme with specific activity of 0.557 U/mg protein was extracted using 60%-70% saturated ammonium sulfate solution supplemented with 200 mmol/L sodium dithionite and 5% glycerol, and the hydrogenase recovery yield was about 30%.
Ammonium Sulfate
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chemistry
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Chemical Precipitation
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Chlorophyta
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enzymology
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Enzyme Stability
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Hydrogen
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metabolism
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Hydrogenase
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isolation & purification
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metabolism
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Seawater
8.pH-Temperature Dependence of Actomyosin Superprecipitation.
Yang Saeng PARK ; Hee Joong KIM ; Joong Woo LEE ; Doo Hee KANG
Yonsei Medical Journal 1981;22(2):85-94
The effect of temperature on the pH-dependence of actomyosin superprecipitation was studied, using actomyosin extracted from the rabbit and frog skeletal muscle tissues. The pH optima of superprecipitation was rather broad in both the rabbit and frog actomyosin. In the frog, superprecipitation measured at 16-42 degrees C was relatively independent of pH variations between 6.7 to 8.5, but it was significantly inhibited at pHs outside of this range, showing a sharp inflection of the curve. The pH at the inflection point was inversely proportional to the incubation temperature, but the (OH-)/(H+) ratio at the inflection point was not changed with temperature. The log (OH-)/(H+) was approximately -0.6 on the acidic side and 3.16 on the alkaline side. Similarly, superprecipitation of the frog actomyosin was virtually independent of the medium pH of the intermediate range (approximately 6.0-8.5); but it was drastically inhibited at pHs below or above this range, thus revealing a sharp inflection of the curve. Again, the pH at the inflection point changed inversely with temperature, preserving a constant (OH-)/(H+) ratio. The log (OH-)/(H+) ratio at the inflection point was approximately -2 on the acidic side and 3.5 on the alkaline side. The above pH effects were not associated with irreversible protein damage or with the changes in buffer species. These results strongly suggest that suppression of the superprecipitation of rabbit and frog actomyosin gels, at a low and high pH, be due to alterations in the fractional dissociation of histidine-imidazole and cysteine-SH groups, respectively.
Actomyosin*
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Animal
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Calcium/physiology
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Hydrogen-Ion Concentration
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Muscle Contraction
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Precipitation
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Rabbits
;
Temperature*
9.Graded ethanol precipitation method on physicochemical properties and antioxidant activities of polysaccharides extracted from Astragalus Radix.
Hong-fa LI ; Song-bo GUO ; Shu-li MAN ; Ya-ya FAN ; Ting-ting WANG ; Xia LI ; Wen-yuan GAO
China Journal of Chinese Materia Medica 2015;40(11):2112-2116
Astragalus polysaccharide has been widely used in food and medicinal industry owing to its health-promoting properties. In order to characterize better the relationship among molecular weight, structure-activity and activities, a simple method was used different concentration of ethanol including 30% (PW30), 50% (PW50), 70% (PW70), 75% (PW75), 80% (PW80) and 90% (PW90) to precipitate Astragalus polysaccharides into different molecular weight. As a result, PW90 showed smooth surface and the strongest antioxidant activity among these six fractions (P < 0.05). In conclusion, graded ethanol precipitation was a simple method to separate Astragalus polysaccharides into different molecular weight with different antioxidant activity fractions.
Antioxidants
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pharmacology
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Astragalus Plant
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chemistry
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Chemical Precipitation
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Ethanol
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chemistry
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Polysaccharides
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chemistry
;
pharmacology
10.Correlations of three important technological parameters in first ethanol precipitation of Danshen.
Xingchu GONG ; Binjun YAN ; Haibin QU
China Journal of Chinese Materia Medica 2010;35(24):3274-3277
OBJECTIVEWater content in concentrated extract (WCCE), the concentration of ethanol used in precipitation (CEA) and the quantity of ethanol added( QEA) are three important variables in the first ethanol precipitation of Danshen injection. In this work, the relationships between the three variables and total solid removal, Danshensu (DSS)retention and DSS purity were investigated.
METHODExperiments according to central composite design were carried out and mathematical models were developed.
RESULTThe models were accurate and predictive. The relative deviations between prediction results and experimental results were less than 3%. The influences of the three variables were discussed with a response surface method. The decrease of WCCE and the increase of CEA both caused more precipitation and increase the purity of DSS. However, more loss of DSS was observed. The increase of QEA increased total solid removal. DSS retention and DSS purity increased first and then decreased when QEA increased.
CONCLUSIONThis result suggests the addition of ethanol should be optimized according to WCCE and CEA to obtain better supernatant
Chemical Precipitation ; Ethanol ; chemistry ; Models, Statistical ; Reproducibility of Results ; Salvia miltiorrhiza ; chemistry ; Water ; chemistry