OBJECTIVETo observe the effects of bitumen fume on neurotransmitter and ultrastructure of mice brain and to investigate the toxicity of bitumen fume on nerve system of mice brain.

METHODSThe experimental mice were forced to inhale the bitumen fume at different exposure level and in different time periods. The contents of the three transmitters dopamine (DA), norepinephrine (NE), 5-hydroxytryptamine (5-HT) in mice brain were measured by the fluorescence meanwhile ultrastructure of mice brain was observed by electronic microscope. The ultrastructure of mice brain was observed under transmission electron microscopy.

RESULTSThe contents of DA, NE and 5-HT in all groups decreased with the increasing of dose and prolonging of time (after 8 week, with the increasing of exposure lever, the content of DA, NE, 5-HT was respectively 2.194, 2.190, 2.181, 2.178 microg/g and 1.148, 1.138, 1.135 and 1.407, 1.403, 1.395 microg), but the results did not show significant differences. The structure of the mitochondria changes included the swollen mitochondria, chromatin margination, pyknosis and apoptosis in neuro cells and the processes of swollen astrocyte cells.

CONCLUSIONThe bitumen fume could induce changes of the ultrastructure of mice brain and affect the contents of neurotransmitter of mice brain.

Animals ; Brain ; metabolism ; ultrastructure ; Female ; Hydrocarbons ; toxicity ; Male ; Mice ; Mice, Inbred Strains ; Neurotransmitter Agents ; analysis

Solvents ; chemistry ; Technology, Pharmaceutical ; methods

Objective To study the change of vascular endothelial growth factor(VEGF) in myocardial tissue and serum of myocardial ischemia in rats.Methods Twenty SD rats were randomly divided into normal control group and test group. Test group was ligated coronary artery,and the control group was pulled on line but not ligated,then observed the change of VEGF.The histological and immunohistochemical method were used for observing the change of VEGF serum in myocardial ischemia in rats' heart.VEGF levels were measured by image analysis.Results Compared with control group,the expression of VEGF in the myocardial ischemia group was increased obviously(P

The purpose of this study is to design push-pull osmotic pump (PPOP) tablets of famotidine using the expert system for the formulation design of osmotic pump of poor water-soluble drug which had been established by the authors. Firstly, the parameters which were requisite of the system input were obtained from literatures and experimental tests. Then the parameters were input into the system, and the program was run. The system displayed the designed formulations sequential. Finally, famotidine PPOP was prepared according to the designed formulations and the in vitro dissolution was carried out. It was found out that the target formulation of famotidine PPOP which could release for 24 hours was obtained in a very short period. Meanwhile, the practicability of the established expert system was proved.
Delayed-Action Preparations ; Drug Delivery Systems ; methods ; Excipients ; chemistry ; Expert Systems ; Famotidine ; administration & dosage ; chemistry ; Osmosis ; Solubility ; Tablets ; Water

AIMTo study the pharmacokinetics and bioequivalence of acipimox sustained-release tablets (SRT) after a single and multiple oral dose in healthy dogs.

METHODSThe plasma concentrations of of SRT and reference capsules with a single and multiple oral doses.

RESULTSThe drug concentration-time profiles fitted to a noncompartment model. After a single dose administration of sustained-release tablets and capsules, the pharmacokinetic parameters were as follows: AUC were (158 +/- 30) and (147 +/- 37) microg x h x mL(-1); Tmax were (4.3 +/- 0.8) and (2.6 +/- 1.3) h; Cmax were (29 +/- 6) and (42 +/- 10) microg x mL(-1); T(1/2) were (2.3 +/- 0.7) and (1.60 +/- 0.10) h; MRT were (6.0 +/- 0.8) and (3.9 +/- 0.7) h, respectively. The relative bioavailability of the sustained-release tablet was (108 +/- 16) %. After a multiple oral administration of sustained-release tablets and capsules, the pharmacokinetic parameters were as follows: AUC were (209 +/- 23) and (195 +/- 26) microg x h x mL(-1); Tmax were (6.3 +/- 0.8) and (3.4 +/- 1.5) h; Cmax were (27 +/- 4) and (36 +/- 5) microg x mL(-1); Cmmin were (2.2 +/- 1.0) and (0.20 +/- 0.20) microg x mL(-1); Cav were (8.7 +/- 1.0) and (8.1 +/- 1.1) micro x mL(-1); FI were (293 +/- 73) % and (448 +/- 91) % , respectively. The relative bioavailability of the sustained-release tablet was (114 +/- 19) %.

CONCLUSIONThe results of two one-side test from single dose administration shown that two preparations were bioequivalent. The Cmax of sustained-release tablet was lower than that of capsules, while the Tmax and MRT of sustained-release tablet were higher than that of capsule, which indicating a good retarding effect. The results from multiple dose administration also shown that two preparations were bioequivalent and the DF of sustained-release tablet was significant lower than that of capsule.

Administration, Oral ; Animals ; Area Under Curve ; Biological Availability ; Capsules ; Delayed-Action Preparations ; Dogs ; Dose-Response Relationship, Drug ; Hypolipidemic Agents ; administration & dosage ; pharmacokinetics ; Pyrazines ; administration & dosage ; pharmacokinetics ; Random Allocation ; Tablets ; Therapeutic Equivalency

OBJECTIVETo measure the spectral transmittance of Cerinate porcelain veneer and enamel in different color and different thickness.

METHODSSamples of Cerinate porcelain veneers were prepared in different thickness (0.50 mm, 0.75 mm, 1.00 mm) and different Vita shade (A1, A2, A3). Enamel samples in shade A2 were made with three thickness (0.50 mm, 0.75 mm, 1.00 mm). A spectrophotometer with spectra range (380-800 nm) was employed to measure the spectral transmittance.

RESULTSSpectral transmittance decreased with the increasing in the thickness of specimens and decreasing in the color darkness. The transmittance of Cerinate porcelain veneer material and enamel in the same color and same thickness hadn't significant difference.

CONCLUSIONThe key factor to spectral transmittance of porcelain veneer materials is veneer's thickness, and the color of the materials has also some influence on it. Cerinate porcelain veneers can properly recover the transparency of teeth.

Ceramics ; Color ; Dental Enamel ; Dental Porcelain ; Dental Veneers ; Humans ; Spectrophotometry

To increase the dissolution rate and extent of valsartan, valsartan nanosuspensions have been prepared. Controlled precipitation assisted with sonication is utilized to prepare valsartan nanosuspensions, the concentration of the drug, stabilizer and costablizer had a great effect on the stability of the preparation according to the pre-experiment. So the method of central composite design-response surface is used to optimize the prescription based on the above three factors and the particle size as the response value. The software Origin 8.0 is used to draw the view of the three-dimensional effects and 2D contour map, to get the optimal prescription area. Valsartan nanosuspensions were prepared. The mean diameter and zeta potential are about 216.6 nm and -57.7 mV, respectively. Compared with the microsuspensions and commercial preparation, the dissolution of valsartan nanosuspensions was faster and the bioavailability can be enhanced to some extent.
Angiotensin II Type 1 Receptor Blockers ; administration & dosage ; chemistry ; Biological Availability ; Chemical Precipitation ; Drug Stability ; Nanoparticles ; administration & dosage ; chemistry ; ultrastructure ; Particle Size ; Research Design ; Solubility ; Suspensions ; Ultrasonics ; methods ; Valsartan ; administration & dosage ; chemistry

AIMTo study the erosion behaviour during dissolution of matrices using different molecular weight polyethylene oxide (PEO) as hydrophilic polymer.

METHODSPEO hydrophilic matrix tablets with no added drug and excipients were prepared by direct compression method. The erosion rates of matrices comprised of pure or blending PEO polymers were evaluated in distilled water at (37 +/- 0.5) degrees C with rotating rate of 50 r x min(-1). The relationship between PEO molecular weight and erosion rate of matrices was investigated by experimental and mathematical model methods.

RESULTSThe gravimetric erosion experimental results indicated that the power-law relationship which relates the polymer erosion rate and weight average molecular weight: k infinity (M(w)) -1.30 4 was proved to have great potential utility in predicting the degree of polymer erosion of matrices comprised of either intermediate molecular weight (97. 98 x 10(4) - 553. 36 x 10(4)) or blends of lower and higher molecular weight polymers. Based on the semiempirical equation for mass transfer rate: Jp = (fp < Dp > (2/3) v (-1/6) omega (1/2)) C(p,dis), a theoretical mathematic model was developed for describing the relationship between PEO erosion rate and PEO weight average molecular weight: Jp infinity M(-1.241), where the exponent of -1. 241 was very close to the exponent of - 1. 130 4 obtained from practical determination.

CONCLUSIONPEO was proved to be a good candidate of hydrophilic polymer and appeared to have great potential for controlled release applications. The mathematic model presented together with the utilization of the erosion behaviour discussed in our study could provide a guide line to predict the degree of polymer erosion for other intermediate polymer grades and / or mixture of the polymers utilized in this study, which could play an active role in designing PEO hydrophilic sustained delivery systems.

Delayed-Action Preparations ; chemistry ; Drug Carriers ; chemistry ; Drug Delivery Systems ; Drug Stability ; Excipients ; chemistry ; Molecular Weight ; Polyethylene Glycols ; administration & dosage ; chemistry ; Polymers ; Solubility ; Tablets ; Water

OBJECTIVEUsing Markov model Monte Carlo simulation to conduct a cost-effectiveness analysis of screening Helicobacter pylori (H. pylori) infection to prevent gastric cancer.

METHODSThe Markov model was developed based on the natural course from H. pylori infection to gastric cancer. Two strategies were compared: (1) screening for H. pylori and treatment for those with positive tests, and (2) without screening and treatment. Data used for model simulation including transition probability, efficacy of test and treatment were collected from related research publications. Markov model Monte Carlo simulation combined with bootstrap method was used to perform base-case analysis and estimate the confidence interval of cost-effectiveness ratios. The probability sensitivity analysis was used to estimate the cost-effectiveness in multiple uncertainty factors.

RESULTSAssuming H. pylori eradication will prevent 50% of attribute gastric cancer, the screening strategies would prevent 16.6% cases of gastric cancer. Cost-effectiveness were 10,405 Yuan (95% CI: 4,238 - 27,727 Yuan) per GC prevented, 64 Yuan (95% CI: 31 - 97 Yuan) per QALY saved and 1,374 Yuan (95% CI: 352 - 86,624 Yuan) per life year saved.

CONCLUSIONScreening and treatment for H. pylori infection in population was potentially effective in the prevention of gastric cancer, and screening in high incidence area of gastric cancer would be more effective and economic.

Cost-Benefit Analysis ; Helicobacter Infections ; complications ; diagnosis ; Helicobacter pylori ; isolation & purification ; Humans ; Markov Chains ; Probability ; Stomach Neoplasms ; prevention & control

Purpose The aim was to examine c-MET,ALK,ROS1 variants in advanced non-small cell lung cancer (NSCLC) patients,and to analysis the association of c-MET,ALK,ROS1 variants with the clinical and pathological features.Methods The c-MET,ALK,ROS1 were detected by fluorescence in situ hybridization (FISH) in the 91 cases of NSCLC specimens.The correlation of c-MET gene amplification with clinicopathological features and the ALK,ROS1 fusions was analyzed.Results The positive rate of c-MET gene amplification was 8.79％ (8/91),the positive rates on male and female were 1.82％ and 19.4％,respectively.In ＜ 60-years-old and ≥60-years-old NSCLC patients,the positive rates were 7.5％ and 8.89％,resepectively.The positive rate was higher in stage Ⅲ than stage Ⅳ (9.62％ vs 7.69％),the c-MET gene amplification was detected in 9.2％ adenocarcinoma patients but none in squamous carcinoma patients.The detection rates of ALK fusions and ROS1 fusions were 10％ and 13.3％,respectively.One patient was detected the coexistence of MET with ROS1 fusion.Conclusion The c-MET gene amplification is correlated with gender,but not with age,histological types and clinical stages.C-MET amplification,ALK fusions and ROS1 fusions are almost no coexistence,but not completely mutually exclusive.To they knowledge,this is the first case report the coexistence of MET amplification with ROS1 fusion in NSCLC.