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 ; Seizures ; Comprehension ; Precipitation ; Epilepsy

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* ; Chemical Precipitation ; Urease/metabolism*

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 ; Ethanol ; Adenosine ; Chemical Precipitation

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 ; Durapatite ; Precipitation ; hydroxyl group

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 ; Chemistry, Pharmaceutical ; methods ; Drugs, Chinese Herbal ; chemistry ; Ethanol ; chemistry

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

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 ; Chemical Fractionation ; methods ; Chemical Precipitation ; Ginsenosides ; chemistry ; isolation & purification ; Molecular Imprinting ; Polymerization ; Polymers ; chemical synthesis

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 ; chemistry ; Chemical Precipitation ; Chlorophyta ; enzymology ; Enzyme Stability ; Hydrogen ; metabolism ; Hydrogenase ; isolation & purification ; metabolism ; Seawater

OBJECTIVETo establish a method integrating multi-targets for determining critical process parameters of the manufacturing process of traditional Chinese medicine.

METHODThe ethanol precipitation process of Danhong injection was taken as an application case of the method established. Fractional factorial design of experiments were conducted. Mathematical models relating seven process parameters to ten targets in the ethanol precipitation process were established. Then the sums of the absolute values of the regression coefficients in the models were used to evaluate the criticality of process parameters.

RESULTWater content in the concentrate, ethanol concentration and ethanol consumption were identified as the critical process parameters.

CONCLUSIONThe method established can integrate multi-targets effectively for the evaluation of critical process parameters.

Chemical Precipitation ; Chemistry, Pharmaceutical ; methods ; Drugs, Chinese Herbal ; chemistry ; isolation & purification ; Salvia miltiorrhiza ; chemistry

OBJECTIVETo study effect of alcohol concentration in water extraction and alcohol precipitation on the preparation of effervescent tablets of Banlangen.

METHODEffects of different concentrations of alcohol precipitation on the Banlangen extract rate, metastasis rate of index components, extract properties of powder, preparation process were investigated, respectively.

RESULTAlcohol concentration on the Banlangen extract rate, metastasis rate of adenosine, extract the amount of saturated moisture, effervescent disintegration time of no significant impact, but spray drying process, dry granulation process.

CONCLUSIONAlcohol concentration has a significant effect on the preparation of effervescent tablets of Banlangen in the process of water extraction and alcohol precipitation, It suggest that the choice of concentration of alcohol precipitation should be based on experimental purposes, the entire preparation process of the system test results.

Chemical Precipitation ; Drugs, Chinese Herbal ; chemistry ; Ethanol ; chemistry ; Tablets ; chemistry ; Technology, Pharmaceutical ; methods ; Water ; chemistry