ABSTRACT
Objective To investigate the specific roles of gap junction and ATP in mechanical stimulation induced calcium transfer in osteoblasts. Methods The isolated osteoblastic pattern without gap junctions was established by using the micropatterning method. Then fluid shear stress was applied on cells using the flow chamber to observe and analyze the characteristic parameters of calcium response. Results Multiple calcium response still occurred in osteoblastic pattern without gap junction, but the response time to the first responsive peak was much longer than that with gap junction. When the intracellular and extracellular calcium ions were removed, only 40% cells responded to the mechanical stimulation, with single peak and multiple peaks accounting for 50%, respectively. If ATP pathway was blocked, only 20% cells responded, most of which showed single peak. Conclusions ATP was the major pathway mediating intercellular calcium transfer, while the gap junction was not the necessary one.
ABSTRACT
Human fibroblast growth factor 20 [FGF20] is a 16.5 kDa protein containing 154 amino acid residues with reportedly poor thermal stability, and low stability, which are considered to be major factors that can limit its pharmacological applications. Thus, the aim of this study was to enhance the thermal stability and bio activity of a therapeutic FGF20 by addition of sucrose or heparin as additives and also at different temperatures. A variety of biophysical techniques such as far-UV circular dichroism [CD], fluorescence and high resolution derivative UV absorption spectroscopy, were employed to characterize FGF20 and study the effects of heparin and sucrose on its thermal stability and bio activity at pH 7.0. Results of this study suggest that human FGF20 is significantly unstable and induction of heat by increased temperatures results in aggregation and precipitation at pH 7.0. Great changes in the fluorescence intensity and shape were achieved by addition of heparin and sucrose at different temperatures compared to the control. From 10 °C to 60 °C, no significant changes were observed in far-UV CD spectrum compared to the control, but significant changes were observed by adding sucrose when these temperatures are above 45 °C. Upon addition of heparin and sucrose, the mitogenic activity increased significantly at all tested temperatures, and these changes may be related to the roles of heparin and sucrose on the structure and conformation of FGF20. Results of this study suggest that heparin and sucrose as additives seems to benjm sufficient to prevent thermal inactivation of FGF20 and also maintain its conformation stability and bio activity
Subject(s)
Humans , Fibroblast Growth Factors/pharmacokinetics , Temperature , Drug Stability , Circular Dichroism , Heparin , SucroseABSTRACT
Chuanxiong is a herb used in traditional Chinese medicine for the Treatment of viral encephalitis. In animal studies it has shown to inhibit the synthesis and activity of Thromboxane [TXA2] and abate the imbalance between Thromboxane [TXA2] and Prostacyclin [PGI2]. As a result, cerebral edema, ischemia and hypoxia could be improved. The aim of this study is to evaluate its effect in the treatment of viral encephalitis in children
Methodology: ninety-nine patients with viral encephalitis were randomly divided into two groups. Ligustrazini Hydrochlorioi [LH] consisting of 51 cases [males 30, females 21; age 5 years and nine month +/- 8 years and 2month] was given LH 4mg/kg per day in 100- 300mls of 10% glucose and infused intravenously over a three to four hour period, for 7 days as a course of treatment. A control groups of 48 cases [males 31, females 17; age 5 years and three month +/- 4 years and three month] received the conventional treatment of Vitamin C[2.0-3.0g], Coenzyme A[100u] and Adenosine Triphosphate [ATP] [40mg] in 100-300 mls of 10% glucose infused intravenously daily for 7 days
Results: the total response rate in the LH group and the control group were 94.12% and 68.75% respectively [u=3.271 p<0.05]. The average time to improvement was 4.29 +/- 1.41 days and 7.31 +/- 2.66 days respectively. No adverse effect was observed in both groups
Conclusion: we conclude that LH is an effective, safe and well tolerated treatment for children encephalitis
ABSTRACT
This study investigated the influence of dissolved oxygen concentration and aeration time on nitrification and nitrite accumulation in an attempt to optimize the recently developed biological-partial-nitritation process for the treatment of strong nitrogen wastewaters. Investigation of dissolved oxygen concentration on ammonium and nitrite oxidation was carried out in a batch reactor. The dissolved oxygen concentration of 0.5 mg O2/L inhibited both ammonium as well as nitrite oxidation, while increase of dissolved oxygen concentration to tilde1 mg O2/L increased the ammonium oxidation rate and was comparable to that at higher dissolved oxygen concentrations. Experiments were carried out in a sequencing batch reactor for more than 100 days to investigate the influence of aeration time on nitrite accumulation. The dissolved oxygen concentration was controlled at tilde1.0 mg O2/L [in the range of 0.8-1.5 mg/L] during the aeration stage, and volatile suspended solid was maintained at 2.0 g/L while temperature and pH were 30 +/- 1§C and 8.3 +/- 0.1, respectively. In a typical cycle, complete nitrification occurred at aeration time longer than 6 h. When the aeration time was reduced to 4 h., tilde80% of partial nitritation was achieved. With a further reduction in aeration time to 3 h., nearly 1:1 nitrite/ammonium ratio was yielded. This result revealed that for the reactor design, aeration time determined by feasibility experiments must be considered based on the nitrogen strength in wastewater and biomass concentration in the reactor with dissolved oxygen concentration of tilde1.0 mg O2/L for satisfactory partial nitrification with subsequent processes such as anaerobic ammonium oxidation