Effect of extrusion process on formability of pellets based on texture properties of extrudates / 中草药

Objective: To analyze the effect of extrusion factors such as extrusion speed, screen hole diameter, and extrusion times on the texture properties of extrudate and the quality of pellets. Methods: In this study, microcrystalline cellulose (MCC) as pelletization aid, lactose, Methocel E5 HPMC, Methocel E15 HPMC, Methocel K100 HPMC, and eight kinds of herbal extracts (extracts of Areca catechu, Patrinia scabiosae folia, Acorus tatarinowii, Sargentodoxa cuneata, Psoralea corylifolia, Dachuanxiong Decoction, Ligusticum chuanxiong, and Gastrodia elata) were used as model drugs. Extrudates were prepared under different levels of process parameters, and one part was used to measure the texture parameters, the other part used for quality evaluation after spheronization. Results: With a large screen hole diameter, it showed that hardness of extrudate became lower and the adhesiveness as well as the springiness was significantly higher, leading to a large particle size and poor roundness of pellets. Repeated extrusion could increase hardness, cohesiveness, chewiness, and resilience of extrudate. Not any strong correlation was found between the extrusion speed and texture properties in the study. Conclusion: The extrusion process could be purposefully selected to prepare ideal pellets accroding to texture properties of extrudate.

Wetting agent dosage screening for traditional Chinese medicine pellet based on torque rheological property / 中国中药杂志

With lubricant and bonding effect simultaneously, wetting agent has direct effect on properties of wet mass and extrudate, thus affecting the forming quality of pellets in extrusion-spheronization process. In this research, 25 representative kinds of traditional Chinese medicine(TCM) were selected as model drugs and 20%, 30% and 40% drug loading were set with MCC as their balling agent. The torque rheological curves were measured to get parameters such as maximum torque (Tmax) and corresponding water addition (WTmax) for these 75 raw materials by a mixer torque rheometer (MTR).The results showed that among 75 representative raw materials, 74 ones could be obtained for spherical pellets under the water addition of WTmax-2. corresponding to the second largest torque in torque rheological curve, suggesting that MTR could be used to select the optimal wetting agent dosage of TCM pellets. So the tedious and expensive pre-production work could be considerably reduced when TCM pellets were prepared.

Effects of omapatrilat on endothelin-1-induced proliferation and synthesis of cardiac fibroblasts / 中国应用生理学杂志

<p><b>AIM</b>To investigate the effects of omapatrilat (OMA) on endothelin-1-induced proliferation of cardiac fibroblasts (CFs).</p><p><b>METHODS</b>Isolated and cultured CFs from neonatal Sprague-Dawley rats (SD) were randomly divided into 7 groups: (1) Control, (2) ET-1, (3) OMA, (4) ET-1 + OMA 10(-9) mol/L, (5) ET-1 + OMA 10(-8) mol/L, (6) ET-1 + OMA 10(-7) mol/L and (7) ET-1 + OMA 10(-6) mol/L. CFs were counted by MTT assay. Cell cycle distribution was determined with a flow cytometer (FCM). [3H]-Proline incorporation was evaluated by scintillation counting. Nitric oxide (NO) was measured by colorimetry.</p><p><b>RESULTS</b>10(-7) mol/L ET-1 significantly increased A490 value and [3H]-Pro incorporation and decreased NO secretion compared with the control group (P < 0.01). 10(-9)-10(-6) mol/L OMA inhibited the effects of ET-1 on CFs in a concentration-dependent manner (P < 0.01 vs. ET-1). In the ET-1 group, the percentage of cells in the S phase was higher than control, which was inhibited by l0(-6) mol/L OMA (P < 0.01 vs. ET-1 and control).</p><p><b>CONCLUSION</b>OMA can restrain the proliferation and collagen synthesis of cardiac fibroblasts induced by endothelin-1, and this effect may be partially mediated by NO.</p>

Study on relationship between bent angles of dental fiber reinforced composites posts and their flexural properties / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To develop a new type of fiber reinforced composites (FRC) posts with optimal bent angles.</p><p><b>METHODS</b>Three kinds of experimental bent posts were made with bent angle of 5 degrees, 10 degrees, and 15 degrees respectively. The flexural strength of all FRC posts was tested with a 3-point bending test.</p><p><b>RESULTS</b>The flexural strength of the posts with 15 degrees was significantly lower than that of 5 degrees and 10 degrees post groups and prefabricated straight group (P < 0.05). There was no significant difference in flexural strength within other groups (P > 0.05).</p><p><b>CONCLUSIONS</b>The experimental FRC posts with bent angles of 0 degrees, 5 degrees, 10 degrees can be accepted clinically.</p>