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Objective: The measurement of compounded topical medications’ uniformity is an important component of quality assessment. This study was aimed to evaluate appropriate mixing time for external preparations using a planetary centrifugal mixer.Methods: In order to evaluate the product uniformity of mixtures of five different steroid cream (Antebate®, Myser®, Methaderm®, Lidomex®, and Locoid®) with three different heparinoid oil-based cream (Hirudoid®, “Nichi-Iko” cream and “Nipro” cream), steroid cream and heparinoid oil-based cream (5 g each) were added into a 13 mL container and mixed using the mixer (NanKo Rentaro NRE-120®, THINKY) at rotation speed of 800 rpm and revolution speed of 2,000 rpm. We sampled 0.1 g of the mixture from three spots (top, middle, and bottom portions) of the container then, measured the steroid content by HPLC method. The yield value points of each cream and heparinoid oil-based cream were also measured by spread meter.Results: Our results showed that when the coefficient of variation (CV) is less than 15.2 %, a mixing time of at least 120 s was required to achieve proper mixing to obtain the permissible limit of steroid cream and heparinoid oil-based cream. Also the greater difference of the yield value between steroid cream and heparinoid oil-based cream tended to be mixed easier.Conclusions: These results suggest that the spread ability of steroid cream and heparinoid oil-based cream affects the mixing efficiency of a planetary centrifugal mixer.
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PURPOSE: This study aimed to identify the level of health problems and the factors that affect health problems for concrete mixer truck divers. METHODS: The questionnaires were administered to 111 drivers in 6 Remicon workplaces located in D city and 7 Remicon workplaces located in K city from September 10 to 28, 2018. A total of 111 questionnaires were collected and 106 were used, excluding 5 incomplete ones. Data were analyzed with frequency, percentage, χ2 test, multiple logistic regression analysis by SPSS/WIN 23.0. RESULTS: The factors affecting subjective health were eating habits, sleeping hours and drinking conditions. The factors that affected chronic diseases were age, eating habits, sleep hours, and drinking conditions. The factors influencing musculoskeletal complaints were work experience, eating habits, and sleep hours. CONCLUSION: The major influencing factors of health problems were eating habits, sleeping hours. This study suggests that it is necessary to run a systematic health care program for the desirable health behaviors in the communities and industrial fields.
Subject(s)
Chronic Disease , Delivery of Health Care , Diagnostic Self Evaluation , Drinking , Eating , Health Behavior , Health Status , Logistic Models , Motor Vehicles , Musculoskeletal DiseasesABSTRACT
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.
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OBJECTIVE: To develop an easy to scale-up preparation process for exenatide-loaded long-acting microspheres, and develop a method that can be used to rapidly evaluate the in vitro release properties of the microspheres. METHODS: The primary emulsion could be made by high shear emulsification process combined with high pressure homogenization method, then exenatide-loaded microspheres were prepared by a modified coacervation method. In the coacervation step, static mixer was used for mixing the primary emulsion and the coacervation reagent. RESULTS: High pressure homogenization could reduce the size of the primary emulsion to about 200 nm. The encapsulation efficiency of microspheres was greater than 96.8%, and the amount of burst release in 1 h was less than 0.5%. When the scale of microspheres preparation was magnified by five times, the characteristics of the obtained microspheres was the same as the small scale batch. The in vitro release curves showed that the continued release time lasted for nearly 4 weeks after the 17 d lag phase. The drug release rate at 45℃ was as high as 2.5 times of that at 37℃, with same release curves. CONCLUSION: The established preparation process of exenatide-loaded long-acting microspheres, which uses static mixer for mixing the primary emulsion and coacervation reagent, is easy for scaling-up and industrialization. Accelerated test at 45℃ can be used to rapidly evaluate the in vitro release profile of the microspheres.
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PURPOSE: Alginate mixers available in the market do not have the automatic proportioning unit. In this study, an automatic proportioning unit for the alginate mixer and controller software were designed and produced for a new automatic proportioning unit. With this device, it was ensured that proportioning operation could arrange weight-based alginate impression materials. MATERIALS AND METHODS: The variation of coefficient in the tested groups was compared with the manual proportioning. Compression tension and tear tests were conducted to determine the mechanical properties of alginate impression materials. The experimental data were statistically analyzed using one way ANOVA and Tukey test at the 0.05 level of significance. RESULTS: No statistically significant differences in modulus of elastisity (P>0.3), tensional/compresional strength (P>0.3), resilience (P>0.2), strain in failure (P>0.4), and tear energy (P>0.7) of alginate impression materials were seen. However, a decrease in the standard deviation of tested groups was observed when the customized machine was used. To verify the efficiency of the system, powder and powder/water mixing were weighed and significant decrease was observed. CONCLUSION: It was possible to obtain more mechanically stable alginate impression materials by using the custom-made proportioning unit.
Subject(s)
TearsABSTRACT
Objective To explore the formulation and preparation technique of rosuvastatin calcium tablets with satisfactory stability and reproducibility. Methods Using suitable formulations, we prepared the rosuvastatin calcium granulates by high shear mixer and fluid bed separately, and compared their influences on the granulate properties, tablet characteristics and dissolution. The reproducibility of formulation and preparation technique was investigated. Furthermore, the factors affecting the formulation were also investigated. Results Compared with the fluid bed, granulation using high sheer mixer was more suitable for preparing rosuvastatin calcium granulates. The selected formulation and preparation technique yielded 3 batches of rosuvastatin calcium tablets which met the quality requirement. The tablets had a comparable dissolution profiles to "Crestor " of AstraZeneca. The stability of rosuvastatin calcium was largely affected by the strong light, high humidity and high temperature. Conclusion The optimized formulation and preparation technique have good reproducibility for preparing rosuvastatin calcium tablets, which have good stability.
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By analyzing the structure and the working principle of Evita 4 HPS valve (HPSV=high-pressure servo-valve) in the mixer unit, and introducing detailed status of troubleshooting to give the solvents. The repairing examples and some effective ways about maintenance of the HPSV are provided at last.
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Along with the ongoing updates and diversity in ventilator design and application,new standards of classification are proposed.Overview and technical analysis are given in illustrations focusing on the working principles of ventilators,in particular the three key components of conduit system(mixer,flow valve and exhalation valve),to provide helpful information for engineers or clinicians in relation to the design,maintenance and usage.