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
;
Powders
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Durapatite
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Precipitation
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hydroxyl group
5.Precipitation reaction between berberine and rheinic acid by capillary electrophoresis.
Xu XU ; Xiao-wei DONG ; Ping MAO
Acta Pharmaceutica Sinica 2003;38(10):779-782
AIMTo study the thermodynamics of precipitation reaction and kinetics between berberine and rheinic acid. The former is the main compound in rhubarb root or corktree bark, the latter is a representation of anthraquinone compounds that are the main kind compound in coptis rhizome. The precipitate produced in preparation of complex prescription of Chinese herbal medicines Xiexin decoction and Shaoyao decoction had made an appeal. The work should build a good basement for two decoctions research and development.
METHODSCapillary electrophoresis (CE) and front analysis methods are used for determining two compounds' equilibrium concentration at different precipitate conditions to calculate the constants of thermodynamics and kinetics.
RESULTSThe molar ratio of berberine and rheinic acid in precipitate is 1:1. The solubility product constant Ksp = [B] [R] = (3.29 +/- 0.19) x 10(-9) mol2.L-2. The precipitate reaction is an endotherm process and Ksp shows less effect by temperature. The reaction occurred immediately even though the precipitate cannot be observed in time. The precipitate process in experiments is practically just an aging or grown process of the precipitate particles. High temperature can quicken the aging.
CONCLUSIONThe precipitate in Chinese herbal medicines Xiexin decoction and Shaoyao decoction should be resulted from anthraquinone compounds and alkaloids. The reproductivity of capillary electrophoresis can be improved for simple sample by combining peak height measurement.
Anthraquinones ; analysis ; chemistry ; Berberine ; analysis ; chemistry ; Chemical Precipitation ; Drug Interactions ; Electrophoresis, Capillary ; Solubility
6.Method for discriminating key quality control indicators of concentrated solution before traditional Chinese medicine ethanol precipitation.
Anyi YAN ; Xingchu GONG ; Haibin QU
China Journal of Chinese Materia Medica 2012;37(11):1558-1563
OBJECTIVETo suggest a method for discriminating quality control indicators of concentrated solution before traditional Chinese medicine ethanol precipitation.
METHODThe second ethanol precipitation (SEP) of Guanxinning was taken as an example, with the concentrated supernatant of first ethanol precipitation (CSFEP) prepared with same dry matter content and the same amount of ethanol as raw materials, to conduct the ethanol precipitation test under the same conditions. The experimental data was analyzed by stepwise regression and partial least squares regression. Both of them selected the parameters which affect phenolic compounds retention ratios in SEP supernatant as the key indicators.
RESULTPhenolic compounds contents in SEP supernatant were mainly affected by the contents of danshensu, caffeic acid and salvianolic acid B in CSFEP.
CONCLUSIONThe discrimination method can be used to discover key quality control indicators of concentrated solution before ethanol precipitation.
Chemical Precipitation ; Ethanol ; chemistry ; Medicine, Chinese Traditional ; standards ; Quality Control ; Solutions
7.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
8.Optimization on alcohol precipitation techniques of Liuwei Dihuang decoction by response surface methodology.
Ming YAN ; Ying-chun WEI ; Xue-feng LI ; Jin MENG ; Yun WU ; Wei XIAO
China Journal of Chinese Materia Medica 2015;40(19):3794-3799
The theoretical basis of the alcohol precipitation process control was provided, the alcohol precipitation was optimized and the relationship equation was got. The monod glycoside, loganin and paeoniflorin were used as the evaluation indexes to determine the impact factors of alcohol precipitation techniques of Liuwei Dihuang decoction by the Plackett-Burman experimental design and the levels of non-significant factors were identified. Then, Box-Behnken response surface methodology was used to research and discuss the critical process parameters influence the effect of alcohol precipitation and draw interaction between key process parameters and the correlation equation with index components. Through the establishment and solving the quadratic regression model of composite score, the optimum preparation conditions of alcohol precipitation techniques of liuwei were as follows: stirring speed was 580 r x min(-1), standing time was 17 hours, alcohol concentration was 34%, the density of Liuwei Dihuang decoction was 1.13. The response surface methodology for optimized alcohol precipitation techniques of Liuwei Dihuang decoction is. reasonable and feasible.
Chemical Precipitation
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Chemistry, Pharmaceutical
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methods
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Drugs, Chinese Herbal
;
chemistry
;
Ethanol
;
chemistry
9.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*
10.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