On Resolving Key Escrow Problem in HIBE and HIBS

Jian-Wu Zheng,Jing Zhao,Xin-Ping Guan 보안공학연구지원센터 2016 International Journal of Security and Its Applicat Vol.10 No.6

In traditional hierarchical identity based cryptosystems (HIBC), non-leaf entities as level PKGs are usually capable of deriving private keys for their descendants with use of their private keys, non-leaf entities can therefore act (decrypt or sign) on the behalf of their arbitrary descendants. This is called key escrow problem of HIBC. In order to resolve key escrow problem, a new technique – Identifier Discrimination is proposed in this paper for composing private keys for entities in hierarchy. With the technique, an identity selective secure HIBE scheme is constructed under Decisional Bilinear Diffie- Helleman (DBDH) assumption in standard security model, in which any identity is incapable of deriving private keys for any of its descendants with use of its private key, and the privilege of generating private keys for each individual descendant is delegated by the root PKG through authorization, that we call Authorization Delegation. Moreover, a new hierarchical identity based signature (HIBS) scheme is constructed from our HIBE construction, by applying Naor transformation of an identity-based signature (IBS) out of an IBE. Because of the inability of deriving its descendants’ private keys with use its private key, an entity therefore cannot sign messages on behalf of any of its descendants, thus guaranteeing that authenticity and non-repudiation properties are achieved in our HIBS system.

Differentiating Technique: Constructing Efficient HIBE with Constant Size Ciphertext and Authorized Delegation

Jian-Wu Zheng,Jing Zhao,Xin-Ping Guan 보안공학연구지원센터 2016 International Journal of Security and Its Applicat Vol.10 No.8

As Hierarchical Identity Based Encryption (HIBE) system usually maps the true institutional structure of an organization or entity relationship between objects in real world, It is important that computation & communication complexity of private key, ciphertext, cryptographic computations and so on related to an entity in the hierarchy is independent to the hierarchy depth of the entity. Moreover, key escrow problem that any non-leaf entity in a hierarchical identity based cryptosystem can derive private keys for its descendants with use of its private key should be resolved, in order to prevent any entity from behaving on behalf of its descendants. In this paper, a new technique is introduced for composing a private key for each individual entity in HIBE system by differentiating between non-local identifiers and local identifiers of the identity of the entity. That we call Identifier Discrimination. With the technique, A selective identity secure HIBE system is constructed under Decisional Bilinear Diffie-Hellman (DBDH) assumption without using random oracles, where the private key and the ciphertext consist of constant number of group elements, and decryption requires only three bilinear map computations, regardless of the identity hierarchy depth. Moreover, in contrast to previous HIBE constructions, where private key for an entity can be derived by its ancestors with direct use of their private keys, key escrow problem inherent in identity based cryptosystems is resolved in our HIBE construction. Privilege of deriving private keys for an entity can be delegated to any of its ancestors through authorization by distributing specifically crafted values to the ancestor in our HIBE system, that we call Authorized Delegation.

miR-340 Reverses Cisplatin Resistance of Hepatocellular Carcinoma Cell Lines by Targeting Nrf2-dependent Antioxidant Pathway

Shi, Liang,Chen, Zhan-Guo,Wu, Li-li,Zheng, Jian-Jian,Yang, Jian-Rong,Chen, Xiao-Fei,Chen, Zeng-Qiang,Liu, Cun-Li,Chi, Sheng-Ying,Zheng, Jia-Ying,Huang, Hai-Xia,Lin, Xiang-Yang,Zheng, Fang Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.23

Many chemotherapeutic agents have been successfully used to treat hepatocellular carcinoma (HCC); however, the development of chemoresistance in liver cancer cells usually results in a relapse and worsening of prognosis. It has been demonstrated that DNA methylation and histone modification play crucial roles in chemotherapy resistance. Currently, extensive research has shown that there is another potential mechanism of gene expression control, which is mediated through the function of short noncoding RNAs, especially for microRNAs (miRNAs), but little is known about their roles in cancer cell drug resistance. In present study, by taking advantage of miRNA effects on the resistance of human hepatocellular carcinoma cells line to cisplatin, it has been demonstrated that miR-340 were significantly downregulated whereas Nrf2 was upregulated in HepG2/CDDP (cisplatin) cells, compared with parental HepG2 cells. Bioinformatics analysis and luciferase assays of Nrf2-3'-untranslated region-based reporter constructor indicated that Nrf2 was the direct target gene of miR-340, miR-340 mimics suppressing Nrf2-dependent antioxidant pathway and enhancing the sensitivity of HepG2/CDDP cells to cisplatin. Interestingly, transfection with miR-340 mimics combined with miR-340 inhibitors reactivated the Nrf2 related pathway and restored the resistance of HepG2/CDDP cells to CDDP. Collectively, the results first suggested that lower expression of miR-340 is involved in the development of CDDP resistance in hepatocellular carcinoma cell line, at least partly due to regulating Nrf2-dependent antioxidant pathway.

The Influence of the Severity of Chronic Virus-Related Liver Disease on Propofol Requirements during Propofol-Remifentanil Anesthesia

Jian Wu,Su-Qin Huang,Qing-Lian Chen,Shu-Sen Zheng 연세대학교의과대학 2013 Yonsei medical journal Vol.54 No.1

Purpose: The purpose of this study was to investigate the influence of chronic virus-related liver disease severity on propofol requirements. Materials and Methods:In this study, 48 male patients with chronic hepatitis B infection were divided into three groups according to Child-Turcotte-Pugh classification of liver function (groups A, B, and C with mild, moderate and severe liver disease, respectively). After intubation, propofol concentration was adjusted by ±0.3 μg/mL increments to maintain bispectral index in the range of 40-60. Target propofol concentrations at anesthesia initiation, pre-intubation and pre-incision were recorded. Results: The initial concentration used in group C was significantly lower than that used in group A or B (p<0.05), whereas no difference was observed between groups A and B. At pre-intubation, the actual required concentration of propofol increased significantly (3.2 μg/mL) in group A (p<0.05), which lead to significant differences between the groups (p<0.05). At pre-incision, the requirements for propofol decreased significantly in both groups A and B (3.0 μg/mL and 2.7 μg/mL, respectively) compared with those at pre-intubation (p<0.05), and were significantly different for all three groups (p<0.05), with group C demonstrating the lowest requirement (2.2 μg/mL). The required concentrations of propofol at pre-incision were similar to those at induction. Conclusion: In this study, propofol requirements administered by target-controlled infusion to maintain similar depths of hypnosis were shown to depend on the severity of chronic virus-related liver dysfunction. In other words, patients with the most severe liver dysfunction required the least amount of propofol.

Effect of Metabolic Structures and Energy Requirements on Curdlan Production by Alcaligenes faecalis

Zheng, Zhi-Yong,Lee, Jin-Woo,Zhan, Xiao Bei,Shi, Zhongping,Wang, Lei,Zhu, Li,Wu, Jian-Rong,Lin, Chi Chung Korean Society for Biotechnology and Bioengineerin 2007 Biotechnology and Bioprocess Engineering Vol.12 No.4

A comprehensive metabolic network was proposed for Alcaligenes faecalis and employed in a stoichiometrically based flux balance model for curdlan production optimization. The maximal yield of curdlan was evaluated for curdlan batch production. Various metabolic structures and metabolic pathway distributions related with the curdlan maximal yield was evaluated. The results showed that the energy efficiency rather than the substrate supply was the major constraint for the enhancement of curdlan production. The increase in specific rate of glucose uptake could enhance curdlan production yield due to the decrease of the ratio of metabolic maintenance to substrate consumption. However, some of the energy loss and nutrient limitation associated with the increase of metabolic maintenance would adversely affect the conversion efficiency of the substrate.

Protraction of mandibular molars through a severely atrophic edentulous space in a case of juvenile periodontitis

Jian-chao Wu,Yu-ting Zheng,Yi-jun Dai 대한치과교정학회 2020 대한치과교정학회지 Vol.50 No.2

Moving the mandibular posterior teeth into a severely atrophic edentulous space is a challenge. A carefully designed force-and-moment system that results in bodily protraction of the posterior teeth with balanced bone resorption and apposition is needed in such cases. This report describes the treatment of a 19-year-old woman with missing mandibular first molars due to juvenile periodontitis. Miniscrews were used as absolute anchorage during protraction of the mandibular second and third molars. Bodily mesial movement of the mandibular second and third molars was achieved over a distance of 11 to 17 mm after 39 months of orthodontic treatment. [Korean J Orthod 2020;50(2):145-154]

Synthesis and Characterization of a Lateral Phthalonitrile Functionalized Main-Chain Polybenzoxazine Precursor

Jian Zheng,Yan Zhang,Ying Wang,Jianqun Gan,Lu Shen,FuBin Luo,Liyan Liang,Kun Wu,Mangeng Lu 한국고분자학회 2016 Macromolecular Research Vol.24 No.5

A lateral phthalonitrile functionalized main-chain polybenzoxazine precursor has been successfully synthesized. The structure was characterized by proton nuclear magnetic resonance (1H NMR) and Fourier transform infrared (FTIR). The formation of benzoxazine rings were confirmed by the characteristic resonances observed at about 4.55 (C-CH2-N) and 5.30 ppm (N-CH2-O) and the absorbance at 950 cm-1 of benzene attached with an oxazine ring. The curing behavior was monitored by differential scanning calorimetry (DSC) and in situ FTIR. The completion of polymerization was proved by the disappearance of the band located at 950 cm-1 in FTIR. Thermogravimetric analysis (TGA) was used to investigate the thermal stability, and the results indicated that the thermal stability of the cured polymer gained significant improvement than that without phthalonitrile functionalization.

Discontinuous Lyapunov functional approach to synchronization of time-delay neural networks using sampled-data

Wu, Zheng-Guang,Park, Ju H.,Su, Hongye,Chu, Jian Springer-Verlag 2012 Nonlinear dynamics Vol.69 No.4

Robust dissipativity analysis of neural networks with time-varying delay and randomly occurring uncertainties

Wu, Zheng-Guang,Park, Ju H.,Su, Hongye,Chu, Jian Springer-Verlag 2012 Nonlinear dynamics Vol.69 No.3

Melatonin Attenuates Mitochondrial Damage in Aristolochic Acid-Induced Acute Kidney Injury

Sun Jian,Pan Jinjin,Liu Qinlong,Cheng Jizhong,Tang Qing,Ji Yuke,Cheng Ke,wang Rui,Liu Liang,Wang Dingyou,Wu Na,Zheng Xu,Li Junxia,Zhang Xueyan,Zhu Zhilong,Ding Yanchun,Zheng Feng,Li Jia,Zhang Ying,Yua 한국응용약물학회 2023 Biomolecules & Therapeutics(구 응용약물학회지) Vol.31 No.1

Aristolochic acid (AA), extracted from Aristolochiaceae plants, plays an essential role in traditional herbal medicines and is used for different diseases. However, AA has been found to be nephrotoxic and is known to cause aristolochic acid nephropathy (AAN). AA-induced acute kidney injury (AKI) is a syndrome in AAN with a high morbidity that manifests mitochondrial damage as a key part of its pathological progression. Melatonin primarily serves as a mitochondria-targeted antioxidant. However, its mitochondrial protective role in AA-induced AKI is barely reported. In this study, mice were administrated 2.5 mg/kg AA to induce AKI. Melatonin reduced the increase in Upro and Scr and attenuated the necrosis and atrophy of renal proximal tubules in mice exposed to AA. Melatonin suppressed ROS generation, MDA levels and iNOS expression and increased SOD activities in vivo and in vitro. Intriguingly, the in vivo study revealed that melatonin decreased mitochondrial fragmentation in renal proximal tubular cells and increased ATP levels in kidney tissues in response to AA. In vitro, melatonin restored the mitochondrial membrane potential (MMP) in NRK-52E and HK-2 cells and led to an elevation in ATP levels. Confocal immunofluorescence data showed that puncta containing Mito-tracker and GFP-LC3A/B were reduced, thereby impeding the mitophagy of tubular epithelial cells. Furthermore, melatonin decreased LC3A/B-II expression and increased p62 expression. The apoptosis of tubular epithelial cells induced by AA was decreased. Therefore, our findings revealed that melatonin could prevent AA-induced AKI by attenuating mitochondrial damage, which may provide a potential therapeutic method for renal AA toxicity.