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.
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