Objective To investigate the pharmacological effects and mechanisms of natural medicine artemisinin and its derivatives. Methods The pertinent domestic and overseas literatures of recent years were reviewed and summarized. Results Artemisinin and its derivatives have unique structure, high efficiency with low toxicity. The pharmacological effects include anti-malaria, anti-tumor, immune function regulation, anti-bacterial, anti-fetation, anti-fibrosis, heat-clearing and detoxicating, etc. Conclusion Artemisinin and its derivatives play pharmacological effects in different ways, and have a good foreground in the application.
Objective To assess the tolerance of preoperative carbohydrate-rich beverage, to determine its effect on postoperative insulin resistance and analyze its potential mechanism. Methods Thirty-two patients undergoing elective colorectal cancer resection were recruited to this randomized controlled study and assigned to two groups at random. Patient in control group was fasted before operation, while patient in study group was given oral water. Homeostasis model assessment (HOMA) indexes, activity of PTK, and mRNA and (or) protein expressions of PKB, PI3K and GluT4 were measured before and (or) immediately after surgery. Furthermore preoperative well-beings of patients were studied. Results Among well-beings, feeling of thirst, hunger and anxiety tended to be better in patients receiving carbohydrate-rich beverages compared with fasted ones (P＜0.05). Whole body insulin sensitivity decreased by 33% in the study group while 38% in the control group (P=0.007 2), and the activity of PTK, expressions of PI3K and PKB in study group were higher than those in control group (P＜0.05， P＜0.01), but no significantly difference was observed about GluT4 in both groups (Pgt;0.05）. Conclusion Preoperative consumption of carbohydrate-containing fluids is safe and effective. Provision of carbohydrate energy source prior to surgery may attenuate immediate postoperative insulin resistance. A carbohydrate-rich drink enhances insulin action at the time of onset of anaesthesia or surgery by activating three kinases named PTK, PI3K, PKB which are key enzymes in pathway of insulin signal transduction. It is likely to explain the effects on postoperative insulin resistance.
Objective To explore the mechanism of mesenchymal stem cells （MSCs） transplantation for chronic hindlimb ischemia in Lewis rats by using cell tracer technique. Methods MSCs were isolated and cultured by using density gradient centrifugation and adherence method respectively， then labeled by 5-bromo-2-deoxyuridine （BrdU）. Eight chronic hindlimb ischemia models of Lewis rats were prepared by using suture-occluded method and then divided randomly to MSCs transplantation group and control group， each group enrolled 4 rats， accepting MSCs transplantation and saline respectively. Then on 7 days and 14 days after transplantation， clinical observation， determination of blood flow， and angiography were performed on rats of the 2 groups. At the same time points after previous tests， rats of the 2 groups were sacrificed to get quadriceps tissues and gastrocnemius tissues to perform HE staining and BrdU immunohis-tochemistry. Results The 8 rats were all survived on 14 days after transplantation， with no tumor happened and necroses in the transplanted area. On 14 days after transplantation， the blood flow ratio of operated side to un-operated side in the hindlimb （1.773 vs. 1.279） of rats in MSCs transplantation group and control group increased， and the angiography results showed that there were no much increase in ratio of collateral vessels number （0.908 vs. 0.835）. There were no significant change in the quadriceps tissues and gastrocnemius tissues by HE staining. The BrdU positive kernels located in the inter-stitial substance cells and vascular endothelia cells， and divided differently in different parts of hindlimb at different time points， that the ratio of positive cells in gastrocnemius tissue was higher than those of quadriceps tissue on 7 days after transplantation， but lower on 14 days. Conclusions MSCs transplantation can increases the blood perfusion of hindlimb in the early stage of chronic hindlimb ischemia model， and the possible mechanism may be the paracrine effect of MSCs but not the number increase of collateral vessels.
ObjectiveTo compare tacrolumus (FK506) with cyclosporine A (CsA) in clinical application to organ transplantation.MethodsThe literature in recent years has been reviewed and compared. ResultsFK506 was a powerful immunosuppression with a mechanism of action similar to that of CsA, but significantly superiori to CsA in terms of prophylaxis and treatment of allograft acute rejection, delay of chronic rejection, and withdrawal of steroid in early period. The cardiovascular mortality and chronic graft nephropathy (CGN),such as hypertension and hyperlipidemia were less frequently seen in FK506treated patients and FK506 also had an acceptable safety profile, including a low incidence of hypertrichosis,gingival hyperplasia and infections.However, CsA had been showed a better result in prevention of posttransplantation diabetes mellitus (PTDM ) and more economic agent than FK506. Pharmacokinetic studies showed CsA in the form of Sandimmun Neoral showed less inter an intrapatient variability than FK506.Meanwhile, the combination of MMF and FK506 or CsA has been proved effectively with excellent graft and patients survival. Conclusion FK506 and CsA are safe and effective long term maintenance immunosuppressive agents in organ transplantation with wonderful prospect.
Obesity is a prevalent metabolic disorder,which seriously affects human health and has become the world's public health problem. Kinase S6K1, an important downstream effector of mammalian target of rapamycin (mTOR), influences specific pathological responses, including obesity, type 2 diabetes and cancer. Presently, S6K1 has become an attractive therapeutic target in the treatment of these disorders. Here, the functions of kinase S6K1, its molecular regulation mechanisms, related pathogenesis of disease and relevant small molecular inhibitors are reviewed. Finally, the prospect of research toward S6K1 is expected as well.
ObjectiveTo summarize and analyze the relevant studies about the tumor suppressor phosphatase and tensin homolog deleted on chromosome ten (PTEN) and thyroid tumor then further elucidate?the possible mechanism of thyroid tumor formation and progression. Mothods Domestic and international literatures investigating the correlation between PTEN and thyroid tumor were retrieved and reviewed. ResultsThe abnormal expression of PTEN protein resulted by the mutation or methylation of PTEN gene may up-regulate the expression of its downstream effectors such as PI3K, mTOR, FAK, etc. This probably correlate with thyroid neoplasia and progression. Conciusions Abnormalites of PTEN and its downstream signal ways may correlate with the initiation and development of thyroid tumors. However, the specific mechanism still remains unclear and need more further researches
ObjectiveTo explore the effect of hydroxyapatite nanoparticle (nHAP) on hepatocellular carcinoma (HCC) and its mechanisms. MethodsThe literatures about the effect of nHAP on HCC were reviewed and summarized. ResultsAs a new nanoparticle, nHAP could suppress the DNA synthesis and subsequent division and proliferation of HCC cells through the inhibition of proliferating cell nuclear antigen (PCNA) and telomerase gene expression and increase of intracellular Ca2+. Moreover, nHAP was able to suppress the differentiation and metastases of HCC cells through the effect on the expressions of Paxillin and P130cas and the decrease of expressions of multiple drug resistance gene protein, microvessel density, and vascular endothelial growth factor. Finally, nHAP induced the apoptosis of HCC tumor cells by the regulation of bcl-2 and bax protein expressions. The combined use of nHAP and chemoembolization drugs could enhance the efficacy, prolong drug duration and reduce toxicity. ConclusionnHAP can inhibit the division, proliferation, differentiation, and metastases, and promote the apoptosis of HCC cells and combined use with chemoembolization drugs can enhance the efficacy and reduce toxicity.