OBJECTIVETo explore a simple but novel method of strengthening gypsum material by cyanoacrylate infiltration. To evaluate the influence of cyanoacrylate on the mechanical properties of dental gypsum models.

METHODSGypsum specimens were polished to the dimension of 35 mmx4 mmx4 mm. Butyl-cyanoacrylate was diluted with chloroform at different concentrations, namely 20% and 30% cyanoacrylate. Gypsum specimens were infiltrated by diluting one component of cyanoacrylate at different concentrations for 8 h and then dried for analysis. The changes in elastic modulus, fracture toughness, compressive strength, biaxial strength, brinell hardness were measured. The data were analyzed using software OriginPro 8.

RESULTSThe viscosity measurements indicated that diluted cyanoacrylate were Newtonian fluids and the viscosity increased slightly within the 48 hours of preparation but still similar as water at room temperature, which could be used to infiltrating gypsum. The gypsum infiltrated with cyanoacrylate exhibited good physicochemical properties. The biaxial strength, fracture toughness, compressive strength and brinell hardness of the gypsum were improved by 39%, 30%, 63% and 18%, respectively.

CONCLUSIONCyanoacrylate can significantly improve the strength of gypsum model which indicates the potential clinical application.

Calcium Sulfate ; Cyanoacrylates ; Dental Models ; Hardness

OBJECTIVETo observe the effect of Yangxue Qingnao Granule (YQG) on the expression of CD11b in CA1 region of hippocampus of vascular dementia rats, and to explore its regulation on microglias.

METHODSTotally 144 SD rats were randomly divided into the sham-operation group, the vascular dementia model group (model), and the YQG treated group (treated). The vascular dementia rat model was prepared by modified Pulsinelli's four-vessel occlusion. Rats in the sham-operation group and the model group were administered with normal saline -(at the daily dose of 10 mL/kg) by gastrogavage, while those in the treated group were administered with YQG (0.32 g/mL, at the daily dose of 10 mL/kg) by gastrogavage. All administration was performed once per day for 8 successive weeks. The expression of CD11b in CA1 region of hippocampus of vascular dementia rats was detected at week 1, 2, 4, and 8, respectively.

RESULTSCompared with the sham-operation group, the expression of CD11b in CA1 region of hippocampus of vascular dementia rats were significantly enhanced in the model group at each time point (P < 0.01). Compared with the model group, the expression of CD11b in CA1 region of hippocampus of vascular dementia rats significantly decreased in the treated group at each time point (P < 0.01), especially at week 2.

CONCLUSIONObvious activation and proliferation of microglias could be seen in CA1 region of hippocampus of vascular dementia rats, and YQG could inhibit activation and proliferation of microglias.

Animals ; CA1 Region, Hippocampal ; drug effects ; metabolism ; CD11b Antigen ; metabolism ; Dementia, Vascular ; drug therapy ; Disease Models, Animal ; Drugs, Chinese Herbal ; pharmacology ; Microglia ; drug effects ; Random Allocation ; Rats ; Rats, Sprague-Dawley

AIM: To establish an experimental model of high intraocular pressure in mice by laser photocoagulation and to prepare for future research.
METHODS: Experimental model of high intraocular pressure was induced unilaterally in 44 C57BL/6 mice. The fellow eye served as a control. TONO-PEN AVIA Tonomter was used to measure intraocular pressure (IOP) to guarantee IOP value at 1, 2, 4, 8wk. Slit-lamp biomicroscopy was performed throughout the period and the structural changes were assessed histologically. And then, their eyes were enucleated, postfixed, cryoprotected, and embedded in optimal cutting temperature medium. After hematoxylin and eosin stain ( HE stain ) , cryosections of the retina were observed under light microscope. TdT-mediated biotin-dUTP nick end labeling ( TUNEL ) was performed on the retinal sections to determine apoptosis rate.
RESULTS: IOP of laser-treated eyes was significantly higher than that of control eyes from 1-8wk (P<0. 05). The highest IOP was 31mmHg, but only one eye. The IOP was mainly around 20mmHg. In laser-treated eyes, the angle of anterior chamber were narrow. Number of cells in the inner nuclear layer and retial gangllion cell layer was slightly lower than that in control eyes at 2wk, but by 4 and 8wk the number of cells was significantly lower than that in the control contralateral eyes.
CONCLUSION: The laser photocoagulation of limbus causes chronic elevation of IOP and this method may be a promising experimental model for the investigation of biological mechanisms of glaucomatous retinal ganglion cell damage.

With low molecular weight chitosan and poloxamer 188 as the joint carriers, ginsenoside Rg3 solid dispersions were prepared by using the solvent evaporation method for an in vitro dissolution test. Subsequently, differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and X-ray diffraction (X-RD) were adopted for a phase analysis. The results showed that the 60 min in vitro cumulative dissolution rate of ginsenoside Rg3 solid dispersions prepared with low molecular weight chitosan and poloxamer 188 at the ratio of 2:1 exceeded 90%, and the drug was dispersed in carriers in an amorphous state. Therefore, ginsenoside Rg3 solid dispersions prepared with low molecular weight chitosan and poloxamer 188 could help significantly improve the drug dissolution, with a practical application value.
Chitosan ; chemistry ; Drug Compounding ; methods ; Ginsenosides ; chemistry ; Molecular Weight ; Poloxamer ; chemistry ; Solvents ; chemistry

Objective To observe the different cerebral activations between pre-administration and post-administration of tryptophan-depleted amino acid mixture (TRP-)/balanced amino acid mixture (BAL) in healthy volunteers through functional magnetic resonance imaging (fMRI) when they received electrical stimulation at the same time. Furthermore, the effects of 5-hydroxytryptamine (5-HT) were explored in pain modulation network. Methods Two-phase crossover design was adopted. Six right-handed healthy volunteers participated in the experiment. TRP- and BAL were administered to each participant according to the Young's method. Volunteers were scanned under fMRI with or without administration of TRP- or BAL when receiving electrical stimulation simultaneously. Analysis of functional neuroimages (AFNI) software was used to show the different activations in the human brain between pre- and post-administration of TRP-/BAL. Then all the results were analyzed by SPSS 14.0. Results (1) Bilateral primary somatosensory cortex (SⅠ) and secondary somatosensory cortex (SⅡ) were activated during pre-administration and post-administration of TRP-, but the activated volumes of bilateral SⅠ and SⅡ during post-administration of TRP- were found significantly larger than that during pre-administration of TRP (P＜0.05). (2) All the activated regions showed no difference between pre- and post-admini-stration of BAL. (3) There were significant differences of pain threshold between pre- and post-admini-stration of TRP- (P＜0.01), which meant that pain threshold reduced remarkably after TRP- administration, while it showed no difference between pre- and post-administration of BAL (P＞0.05). Conclusion 5-HT plays an important role in pain modulation in the central nervous system, TRP- causes acute tryptophan depletion (ATD) through reducing the level of 5-HT in the human brain, which can induce the decrease of volunteers' pain threshold. The activated volumes of bilateral SⅠ and SⅡ display signi-ficant difference between pre- and post-administration of TRP-, suggesting these brain areas may not only involve in the 5-HT related activities but in pain modulation network as well.

Objective To observe the diurnal variation of intraocular pressure(IOP)measured with Goldmann applanation tonomoter(GAT)in patients with primary open angle glaucoma(POAG),normal tension glaucoma(NTG)and healthy controls,and to compare the differences of diurnal variation curves between two eyes of each subject and define the distribution of the peak of IOP. Design Prospective case series.Participants POAG patients,NTG patients and healthy controls.Methods The diurnal variation of IOP in the two eyes of each of 30 POAG patients,30 NTG patients and 30 normal controls were investigated and the distributions of the peak IOP were observed.Main Outcome Measure Intraocular pressure.Results Measured with GAT,6.7% right eyes and 10.0% left eyes of normal people,20.0% right eyes and 23.3% left eyes of NTG patients,and 23.3% right eyes and 20.0% left eyes of POAG patients showed peak IOP at the time points of out-office period.Conclusions POAG patients,NTG patients and normal controls have asymmetric IOP diurnal variation.The two eyes of one individual cannot always be treated as the same.The IOP peak can occur at the time point during the out-office time.Measure IOP in office-time only may miss the dynamic information of IOP.

Background Retinal neovascularization disease is a common cause of blinding.Retinal neovascularization is related to enhancing proliferation of vascular endothelial cells.So how to inhibit proliferation of vascular endothelial cells is a hot burning issue.p21 is known to be involved in the regulation of cell cycle and therefore inhibit the cell proliferation.However,the relationship of p21 and the proliferation of vascular endothelial cells in retinal neovascularization disease is for further study.Objective The aim of this experiment was to study the proliferation of rhesus retinal vascular endothelial cells(RF/6A) and expression of p21 in RF/6A cells under the hypoxia condition,and discuss their association.Methods The RF/6A cells were cultured and passaged in vitro,then they were randomly divided into normoxia culture group(5％ CO2 +95％ O2) and hypoxia for 1 hour,3,6,12 hours group(1％ 02+5％ CO2 +94％ N2).Flow cytometer(FCM) was used to check the distribution of RF/6A cell cycle in the normoxia culture group and hypoxia for 1 hour,3,6,12 hours groups.MTT assay was used to detect and compare the cell proliferation(A570)among the various groups.The expression of p21 in the cells was analyzed by Western blot.Results FCM showed that the cells proportion of G0/G1 stage was reduced initially and then increased afterward in hypoxia for 1 hour and 3,6,12 hours groups,showing a significant difference among 5 groups (F =20.083,P =0.000),and the cells proportion of S stage and G2/M stage were increased firstly and then declined in different hypoxia groups with statistical significances (F =7.861,P =0.001 ; F =10.305,P =0.003).Compared with normoxia culture group,cells proportion of G0/G1 stage was declined and that of S stage and G2/M stage were raised after hypoxia culture,showing statistically signifcant differences(P＜0.05).MTT showed that cell multiplication capacity(A570 value)strengthened firstly and then weakened in hypoxia groups with time prolongation,showing a significant difference among all the groups(F=7.768,P=0.001),and A570 value in hypoxia for 3 hours and 6 hours groups (0.315± 0.062,0.365 ± 0.064) was significantly higher than that of the normoxia group (0.205 ± 0.063),respectively(P＜0.05).Western blot showed that the expression of p21 in the cells down-regulated at the beginning and then up-regulated with the increase of hypoxia time,and there was statistical significance (F =16.738,P=0.000).The p21 relative levels in different hypoxia groups were reduced in comparison with the normoxia group,showing statistical signifcances(P＜0.05).Conclusions Short-term hypoxia could reduce the expression of the p21 in RF/6A and induce cell proliferation initially,then p21 increases and cell proliferation is inhibited with the prolongation of hypoxia time.

Objective To analyze the etiologic factors and clinical manifestation of intraventricular hemorrhage (IVH) in preterm infants.Methods One hundred and seventy-two preterm infants from June 2005 to August 2006 were accrued to investigate their gestational age,birth weight,birth history,and clinical symptoms.Cranial chromatic ultrasound was used to scan the preterm infants and diagnose IVH.Results 1.The incidence of IVH was associated with gestational age (?2=6.40 P=0.011);2.The incidence of IVH was also associated with birth weight(?2=26.49 P=0);3.IVH usually occurred within 72 h with mild clinical manifestations and was diagnosed within 5 days after birth;4.IVH occurred more frequently and more severe in infants with severe asphyxia than those with mild asphyxia.Conclusions Early gestational age,low birth weight, and severe asphyxia are risk factors for IVH.The clinical symptoms of IVH are usually mild in most patients.Cranial chromatic ultrasound is a reliable,sensitive and convenient method of detection for IVH in preterm infants.

OBJECTIVE To detect the expression of the Glucocorticoid receptor-?(GR-?)mRNA in nasal polyp and normal nasal mucosa and investigate the route of nasal drug administration in patients of nasal polyp. METHODS The expression of GR-?mRNA in 101 samples of nasal polyps and 31samples of normal nasal mucosa was examined by using Fluorescent quantitative PCR .RESULTS The level of GR-?mRNA in normal nasal mucosa(135.4? 5.25)?104 copy /?g were significantly higher than that in nasal polyps(23.5?12.1)?104 copy/?g . CONCLUSION Because of the low expression of GR-?mRNA in nasal polyps,the route of nasal drug administration in patients with nasal polyps may be in the part of normal mucosa,not in the mucosa of nasal polyps of the nasal cavity.

To prepare ginseng saponin Compound K with ultrasound-assisted total zymolytic ginseng saponins. The conversion rate was taken as the index to detect the pre-treatment factors such as ultrasonic power and ultrasonic time, as well as the impact of enzymatic factors, such as pH value, temperature, concentration of substrate, dosage of enzyme and reaction time, on the conversion rate. The response surface method was used to optimize the preparation conditions. The enzymolytic products were identified with MS, 1H-NMR and 13C-NMR. The results showed that the optimum conditions of the ultrasound-assisted enzymolysis were 250 W for ultrasonic power, 15 min for ultrasonic time, 5.5 for enzymolytic pH, 50 degrees C for enzymolytic temperature, 36 h for enzymolytic time, 4:5 for enzymolytic dosage: substrate and 1.0 g x L(-1) for concentration of substrate. The relative molecular mass of reaction products was 622.4. Therefore, the nuclear magnetic map verified that the reaction product was rare ginseng saponin Compound K. Under the above conditions, based on the total zymolytic ginseng saponins, the conversion rate of rare ginseng saponin Compound K was 6.91% in proportion to the total of ginsenosides. The process features gentle reaction conditions, high conversion rate and simple and reliable process, which is suitable for industrial production.
Chemistry, Pharmaceutical ; Drugs, Chinese Herbal ; chemistry ; isolation & purification ; Enzymes ; chemistry ; Panax ; chemistry ; Plant Roots ; chemistry ; Saponins ; chemistry ; isolation & purification ; Ultrasonics ; methods