Multi-factor authentication(MFA)was proposed by Pointcheval et al.[Pointcheval and Zimmer(2008)]to improve the security of single-factor(and two-factor)authentication.As the backbone of multi-factor authentication,bio...Multi-factor authentication(MFA)was proposed by Pointcheval et al.[Pointcheval and Zimmer(2008)]to improve the security of single-factor(and two-factor)authentication.As the backbone of multi-factor authentication,biometric data are widely observed.Especially,how to keep the privacy of biometric at the password database without impairing efficiency is still an open question.Using the vulnerability of encryption(or hash)algorithms,the attacker can still launch offline brute-force attacks on encrypted(or hashed)biometric data.To address the potential risk of biometric disclosure at the password database,in this paper,we propose a novel efficient and secure MFA key exchange(later denoted as MFAKE)protocol leveraging the Pythia PRF service and password-to-random(or PTR)protocol.Armed with the PTR protocol,a master password pwd can be translated by the user into independent pseudorandom passwords(or rwd)for each user account with the help of device(e.g.,smart phone).Meanwhile,using the Pythia PRF service,the password database can avoid leakage of the local user’s password and biometric data.This is the first paper to achieve the password and biometric harden service simultaneously using the PTR protocol and Pythia PRF.展开更多
Objective: To investigate the effect of MEK1 inhibitor PD98058 on Tec and ERK2 in HepG2 hepatoma cells. Methods: The expression of mRNA and protein of Tec and ERK2 in HepG2 cells was detected by immunocytochemistry as...Objective: To investigate the effect of MEK1 inhibitor PD98058 on Tec and ERK2 in HepG2 hepatoma cells. Methods: The expression of mRNA and protein of Tec and ERK2 in HepG2 cells was detected by immunocytochemistry as- say. After various concentration of PD98059 treatment, the expression of Tec and ERK2 mRNA in HepG2 cells was detected by RT-PCR and Western blotting. Results: Tec and ERK2 expressed highly in HepG2 cells. PD98059 obviously inhibited the expression of mRNA and protein of Tec and ERK2 in a dose-dependent manner, in which 40 μmol/L of PD98059 exhibited the strongest inhibiting effect. Conclusion: PD98058, as MEK1 inhibitor, can inhibit Tec, block the signal route of Ras/Raf/ERK and to impede the signal transduction in HepG2 cells. Tec may be the signal protein in the upper stream of Ras/Raf/ERK in hepatocarcinoma cells and is supposed to interact with the signal way of Ras/Raf/ERK.展开更多
基金This work was supported by the National Natural Science Foundation of China(No.61802214)the Natural Science Foundation of Shandong Province(Nos.ZR2019BF009,ZR2018LF007,ZR2017MF0,ZR2016YL011)+2 种基金the Shandong Provincial Key Research and Development Program of China(2018GGX1010052017,CXGC07012016,GGX109001)the Project of Shandong Province Higher Educational Science and Technology Program(No.J17KA049)the Global Infrastructure Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Science and ICT(NRF-2018K1A3A1A20026485).
文摘Multi-factor authentication(MFA)was proposed by Pointcheval et al.[Pointcheval and Zimmer(2008)]to improve the security of single-factor(and two-factor)authentication.As the backbone of multi-factor authentication,biometric data are widely observed.Especially,how to keep the privacy of biometric at the password database without impairing efficiency is still an open question.Using the vulnerability of encryption(or hash)algorithms,the attacker can still launch offline brute-force attacks on encrypted(or hashed)biometric data.To address the potential risk of biometric disclosure at the password database,in this paper,we propose a novel efficient and secure MFA key exchange(later denoted as MFAKE)protocol leveraging the Pythia PRF service and password-to-random(or PTR)protocol.Armed with the PTR protocol,a master password pwd can be translated by the user into independent pseudorandom passwords(or rwd)for each user account with the help of device(e.g.,smart phone).Meanwhile,using the Pythia PRF service,the password database can avoid leakage of the local user’s password and biometric data.This is the first paper to achieve the password and biometric harden service simultaneously using the PTR protocol and Pythia PRF.
基金Supported by grants from the National Natural Science Foundation of China (No. 30370341, 30570410)the Academic Foundation for Au-thors of National Excellent Doctoral Dissertation of China (No. 200261).
文摘Objective: To investigate the effect of MEK1 inhibitor PD98058 on Tec and ERK2 in HepG2 hepatoma cells. Methods: The expression of mRNA and protein of Tec and ERK2 in HepG2 cells was detected by immunocytochemistry as- say. After various concentration of PD98059 treatment, the expression of Tec and ERK2 mRNA in HepG2 cells was detected by RT-PCR and Western blotting. Results: Tec and ERK2 expressed highly in HepG2 cells. PD98059 obviously inhibited the expression of mRNA and protein of Tec and ERK2 in a dose-dependent manner, in which 40 μmol/L of PD98059 exhibited the strongest inhibiting effect. Conclusion: PD98058, as MEK1 inhibitor, can inhibit Tec, block the signal route of Ras/Raf/ERK and to impede the signal transduction in HepG2 cells. Tec may be the signal protein in the upper stream of Ras/Raf/ERK in hepatocarcinoma cells and is supposed to interact with the signal way of Ras/Raf/ERK.
