1.Study on gatifloxacin in situ pH-sensitive gel release in vitro
Yajing XU ; Rongfeng HU ; Hui YIN ; Yu GAO
Chinese Journal of Biochemical Pharmaceutics 2010;31(2):107-110
purpose To investigate the release properties of gatifloxacin in situ pH-sensitive gel in vitro.Methods The improved paddle method and the membraneless model were applied in assessing the drug release behavior.Results The gel erosion and drug release were increased with the increase of surface area and shaking frequency.The cumulative quantities of gel erosion were well correlated with the cumulative release of drug loaded in the gel.Conclusion Gatifloxacin was released from in situ pH-sensitive gel with zero-order kinetics characters,and drug release was mainly controlled by gel erosion.
2.Neuroprotective effect of bFGF on cerebral diffuse axonal injuries of rats
Hongqi LI ; Yuzhi ZHANG ; Rongfeng GAO ; Zhanbo ZHANG ; Gang CHENG
Chinese Journal of Rehabilitation Theory and Practice 2003;9(7):414-415
ObjectiveTo observe the neuroprotective effect of basic fibroblast growth factor(bFGF)on cerebral diffuse axonal injuries (DAI)of rats.Methods40 male SD rats were randomly divided into control group, DAI injury group, bFGF group and DAI saline group. According to the survival time of rats, DAI injury group were divided into five groups, the 6h, 12h, 24h, 72h and 7th day group, The changes of bFGF expression in cerebral cortex were detected by immunohistochemical method from 6h to 7d after DAI. Two hours before DAI, bFGF 10μl was injected into right ventricle in bFGF group. ResultsThe bFGF expression appeared at 6h after DAI, increased at 12h, reached the highest level at 72h, and kept in a high level at 7d.There were obvious differences between 72h group and other groups in DAI injury group (P<0.01),cerebral cortex neurons were obviously decreased by HE staining. In each time group,injured neurons were decreased in bFGF group combined with DAI injury group(P<0.05). ConclusionsbFGF has obvious neuroprotective effect on cerebral diffuse axonal injuries of rats.
4. Clinical characteristics and outcome comparison between atrial fibrillation patients underwent catheter ablation under general aesthesia or local anesthesia and sedation
Junjie XU ; Lianjun GAO ; Dong CHANG ; Xianjie XIAO ; Rongfeng ZHANG ; Jing LIN ; Ziming ZHAO ; Hao ZHANG ; Yunlong XIA ; Xiaomeng YIN ; Yanzong YANG
Chinese Journal of Cardiology 2017;45(11):935-939
Objective:
To compare the outcome of radiofrequency catheter ablation under local anesthesia/sedation (S) or general anesthesia(GA) in atrial fibrillation patients.
Methods:
Data of 498 patients with atrial fibrillation undergoing radiofrequency catheter ablation in our departmentfrom January 2014 to December 2015 were retrospectively analyzed. Two hundred and twenty patients assigned to the GA group, the other 278 patients to the S group. Patients were followed clinically every 3 months within one year after procedure. Immediate electrocardiogram was performed in patients with palpitation or choking sensation in chest. The end point of the study was recurrence of any atrial tachyarrhythmia lasting >30 seconds in device interrogation, 24-hour Holter monitoring or 12-lead electrocardiogram after a single procedure. After the ablation procedure, a blanking period of 3 months was allowed according to the guidelines. Procedure time, radiofrequency time, fluoroscopy time, the detection of paroxysmal supraventricular tachycardia, the success rate and the complications were compared between the two groups.
Results:
There was no difference in the baseline characteristics between the two groups, such as age, gender, BMI, complications, LVEF, LAD (all
5.Self-microemulsifying drug delivery system for improving the bioavailability of huperzine A by lymphatic uptake.
Fang LI ; Rongfeng HU ; Bin WANG ; Yun GUI ; Gang CHENG ; Song GAO ; Lei YE ; Jihui TANG
Acta Pharmaceutica Sinica B 2017;7(3):353-360
Huperzine A (Hup-A) is a poorly water-soluble drug with low oral bioavailability. A self-microemulsifying drug delivery system (SMEDDS) was used to enhance the oral bioavailability and lymphatic uptake and transport of Hup-A. A single-pass intestinal perfusion (SPIP) technique and a chylomicron flow-blocking approach were used to study its intestinal absorption, mesenteric lymph node distribution and intestinal lymphatic uptake. The value of the area under the plasma concentration-time curve (AUC) of Hup-A SMEDDS was significantly higher than that of a Hup-A suspension (<0.01). The absorption rate constant () and the apparent permeability coefficient () for Hup-A in different parts of the intestine suggested a passive transport mechanism, and the values ofandof Hup-A SMEDDS in the ileum were much higher than those in other intestinal segments. The determination of Hup-A concentration in mesenteric lymph nodes can be used to explain the intestinal lymphatic absorption of Hup-A SMEDDS. For Hup-A SMEDDS, the values of AUC and maximum plasma concentration () of the blocking model were significantly lower than those of the control model (<0.05). The proportion of lymphatic transport of Hup-A SMEDDS and Hup-A suspension were about 40% and 5%, respectively, suggesting that SMEDDS can significantly improve the intestinal lymphatic uptake and transport of Hup-A.
6.Recent advances in diverse nanosystems for nitric oxide delivery in cancer therapy.
Dan GAO ; Sajid ASGHAR ; Rongfeng HU ; Su CHEN ; Ruixin NIU ; Jia LIU ; Zhipeng CHEN ; Yanyu XIAO
Acta Pharmaceutica Sinica B 2023;13(4):1498-1521
Gas therapy has been proven to be a promising and advantageous treatment option for cancers. Studies have shown that nitric oxide (NO) is one of the smallest structurally significant gas molecules with great potential to suppress cancer. However, there is controversy and concern about its use as it exhibits the opposite physiological effects based on its levels in the tumor. Therefore, the anti-cancer mechanism of NO is the key to cancer treatment, and rationally designed NO delivery systems are crucial to the success of NO biomedical applications. This review summarizes the endogenous production of NO, its physiological mechanisms of action, the application of NO in cancer treatment, and nano-delivery systems for delivering NO donors. Moreover, it briefly reviews challenges in delivering NO from different nanoparticles and the issues associated with its combination treatment strategies. The advantages and challenges of various NO delivery platforms are recapitulated for possible transformation into clinical applications.