Secure access control using updateable attribute keys.

In the era of cloud computing, the technique of access control is vital to protect the confidentiality and integrity of cloud data. From the perspective of servers, they should only allow authenticated clients to gain the access of data. Specifically, the server will share a communication channel with the client by generating a common session key. It is thus regarded as a symmetric key for encrypting data in the current channel. An access control mechanism using attribute-based encryptions is most flexible, since the decryption privilege can be granted to the ones who have sufficient attributes. In the paper, the authors propose a secure access control consisting of the attributed-based mutual authentication and the attribute-based encryption. The most appealing property of our system is that the attribute keys associated with each user is periodically updatable. Moreover, we will also show that our system fulfills the security of fuzzy selective-ID assuming the hardness of Decisional Modified Bilinear Diffie-Hellman (DMBDH) problem.

Sigmoid colon translocation of an intrauterine device misdiagnosed as a colonic polyp: A case report.

RATIONALE: Intrauterine contraceptive devices (IUDs) are recommended as a means of contraception. Translocation of IUD is a rare and serious complication. Colonic inflammatory mass caused by translocated IUD initially misdiagnosed as a colonic polyp is extremely rare and has not been reported yet. PATIENT CONCERNS: This report presents a case of sigmoid colon translocation of intrauterine device on a 37-year-old female patient. Colonoscopy was performed due to her complain of repeated blood in stools and subsequently the patient was misdiagnosed as a sigmoid colon polyp. Nonetheless, the "polyp" was not able to be removed endoscopically. DIAGNOSES: Sigmoid colon translocation of an intrauterine device. INTERVENTIONS: To further clarify the diagnosis, computed tomography (CT) scan was performed and the "polyp" was confirmed to be caused by a translocated IUD. OUTCOMES: The translocated IUD was removed easily by surgery, and the patient recovered soon after the operation. LESSONS: The present case indicates that an annual gynaecologic examination is necessary to determine the position of the IUD, and a CT examination may help confirm an ectopic IUD.

Cobalt-Catalyzed Peroxidation of 2-Oxindoles with Hydroperoxides.

A highly efficient and facile cobalt-catalyzed C-H activation and peroxidation of 2-oxindoles was reported, which provides a new pathway for the synthesis of biologically active 3-peroxy-2-oxindoles from readily available starting materials in excellent chemical yields. The resulting products could be further transformed into various substituted 3-peroxyoxindoles in good to excellent yields. The developed method has been successfully applied to the synthesis of the natural product (±)-N-[2-(3-hydroxy-2-oxo-2,3-dihydro-1H-indol-3-yl)ethyl]acetamide.

FeCl3-Mediated Radical Tandem Reactions of 3-Benzyl-2-oxindoles with Styrene Derivatives for the Stereoselective Synthesis of Spirocyclohexene Oxindoles.

A novel FeCl3-mediated reaction of 3-benzyl-2-oxindoles with styrene derivatives was developed. The reaction provided spirocyclohexene oxindoles in good yields and excellent diastereoselectivities via a tandem radical addition/cyclization process.

A metal-free yne-addition/1,4-aryl migration/decarboxylation cascade reaction of alkynoates with Csp(3)-H centers.

A metal-free cascade reaction of aryl alkynoates with five different types of radical precursors (R-H) through an yne-addition/1,4-aryl migration/decarboxylation process was reported, which allowed facile and convenient access to functionalized vinyl products with "R" and protons located at the identical carbon of the formed double bond.

Quinones and coumarins from Ajania salicifolia and their radical scavenging and cytotoxic activity.

1,4-Naphthoquinone (1) and a new coumarin (3) were isolated from Ajania salicifolia, together with two known compounds (2, 4). The structures and stereochemistry of new compounds were elucidated using spectroscopic methods. Two compounds exhibited potent ABTS cation radical scavenging activities with IC50 values ranging 7.97-8.44 µM. Two quinones (1, 2) exhibited moderate cytotoxic activity against the human cancer cell lines (Hela, HepG2, and K562) with IC50 values of 11.24-35.15 µM in vitro. This is the first report of naphthoquinone in the genus Ajania.

New nor-ursane type triterpenoids from Gelsemium elegans.

Five new nor-ursane type triterpenoids, gelse-norursane A-E, together with twenty known compounds, were isolated from the whole plant of Gelsemium elegans. The structures of new compounds were established as (2R,3R,7R,17S,19R)-2,3,7,19-tetrahydroxy-6-oxo-24-norurs-4(23),12-dien-28-oic acid (1), (2R,3R,7R,17S)-2,3,7-trihydroxy-6-oxo-24-norurs-4(23), 12-dien-28-oic acid (2), (2R,3R,7R,17S)-2,3,4-trihydroxy-23-norurs-20(30),12-dien-28-oic acid (3), (2R,3R,30R)-2,3-dihydroxy-24-norurs-4(23),12-dien-30-oic acid (4), and (2R,3R,30R)-2, 3-dihydroxy-24-norurs-4,12-dien-30-oic acid (5), using spectroscopic analysis, including HRESIMS, 1D and 2D NMR. The absolute configurations of 1 and 4 were established through comparison of experimental and calculated ECD spectra. The gelse-norursane A-E are isolated as the 24-nor-ursane type triterpenoids from the family Loganiaceae for the first time. The cytotoxicities of the selected compounds against a panel of four human cancer HL60, Hela, Hep-G2, and Smmc 7221 cell lines were evaluated using the MTT assay in vitro.

Fe(III)-Catalyzed Cross-Dehydrogenative Arylation (CDA) between Oxindoles and Arenes under an Air Atmosphere.

An efficient Fe(III)-catalyzed cross-dehydrogenative arylation (CDA) of 3-substituted oxindoles with activated arenes under an air atmosphere was developed to provide 3,3'-disubstituted oxindoles in good yields.

Iodine-Catalyzed Direct Olefination of 2-Oxindoles and Alkenes via Cross-Dehydrogenative Coupling (CDC) in Air.

A direct intermolecular olefination of sp(3) C-H bond between 2-oxindoles and simple alkenes via a Cross-Dehydrogenative Coupling (CDC) strategy has been developed. In the absence of additional base, moderate to excellent yields have been obtained by using a catalytic amount of iodine with atmospheric oxygen as the reoxidant. Based on the observation of a radical capture experiment, the transformation is proposed to proceed via a radical process.

[A study involving antioxidizability and cytotoxicity of two kinds of phenol from Ajania Salicifolia and their mechanisms of apoptosis].

OBJECTIVE: To extract two kinds of phenols 4-hydroxy-3, 5-dimethoxy-4-(2-oxopropyl) cyclohexa-2, 5-dien-l-one and 6-methoxy-5,7-dihydroxy coumarin (named as I and H compounds respectively) from Ajania salicifolia and to investigate their antioxidation and cytotoxicity to tumors and explore their pro-apoptosis mechanism. METHODS: The antioxidant activities of two compounds were assessed by ABTS and DPPH radical-scavenging assays. Two compounds were evaluated for their cytotoxicity against human chronic myelogenous leukemia (K562) cells using the MIT assay. The expression of NF-kappaB P65 mRNA in K562 apoptotic cells was measured by reverse transcription-polymerase chain reaction (RT-PCR), real-time quantitative PCR. In addition, protein expression levels of the NF-ICB P65, p-Akt, Fas, P-catenina and E-cadherin were also measured by Western blot. RESULTS: (1) We found that compound I displayed significant inoxidizability, while compound II had no obvious antioxidizability. (2) In cytotoxicity experiments, compound I didn't display cytotoxicity while compound H displayed obvious cytotoxicity. (3) Compared with the blank group, the expression of NF-kappaB P65 mRNA in K562 cell after treatment with compound II was obviously up-regulated. (4) Compared with the blank group, the expression levels of NF-kappaB P65, Fas, beta-catenina and E-cadherin were significantly increased in compound II treated groups and it appeared obvious dose-effect relationship between the expression of protein and drug concentration. CONCLUSION: Two phenols have obvious antioxidizability and cytotoxicity respectively. On the one hand, the tumor-suppressing mechanism of compound II maybe act by up-regulation the expression of NF-kappaB P65 and Fas protein; thereby, affecting the classical Fas apoptosis signaling pathways. On the other hand, it can also up-regulate the expression of protein beta-catenin and E-cadherin, which participate in the adhesion between cells, and accordingly, playing an important role in preventing the proliferation and metastasis of cancer cells.

Radical scavenging activity and cytotoxicity of active quinic acid derivatives from Scorzonera divaricata roots.

Five new quinic acid derivatives and two known 3-O-feruloylquinic acids were isolated from the roots of Scorzonera divaricata Turcz. The new compounds were elucidated as (-)-1,4-di-O-feruloyl-3-O-dihydrocaffeoylquinic acid, (-)-1-O-feruloyl-4-O- dihydrocaffeoylquinic acid, (-)-3,5-di-O-feruloylquinic acid, (-)-1-O-feruloyl-3-O-dihydro- caffeoylquinic acid, and (-)-1-O-feruloyl-5-O-dihydrocaffeoylquinic acid based on extensive spectroscopic studies, including one- and two-dimensional NMR, HRESIMS, UV, and IR results. Five compounds were assessed for antioxidant activity by ABTS and DPPH radical-scavenging assays and for their cytotoxicity against HL-60 and Hep-G2 cell lines by the MTT assay. Three quinic acid derivatives exhibited strong antioxidant activity, with IC(50) values of 3.95, 5.87, and 7.45 µg/mL against ABTS(+) and 11.7, 13.6, and 50.1 µg/mL against DPPH(). (-)-1,4-Di-O-feruloyl-3-O-dihydrocaffeoylquinic acid also exhibited moderate activity against Hep-G2 cell lines with an IC(50) value of 14.6 µg/mL.

Inhibitory effects of Zengshengping fractions on DMBA-induced buccal pouch carcinogenesis in hamsters.

BACKGROUND: Zengshengping (ZSP) tablets had inhibitory effects on oral precancerous lesions by reducing the incidence of oral cancer. However, the severe liver toxicity caused by systemic administration of ZSP limits the long-term use of this anti-cancer drug. The purpose of this study was to evaluate the tumor inhibitory effects due to the topical application of extracts from ZSP, a Chinese herbal drug, on 7, 12-dimethlbenz(a)anthracene (DMBA) induced oral tumors in hamsters. The study also investigated the anti-cancer mechanisms of the ZSP extracts on oral carcinogenesis. METHODS: DMBA (0.5%) was applied topically to the buccal pouches of Syrian golden hamsters (6 - 8 weeks old) three times per week for six weeks in order to induce the development of oral tumors. Different fractions of ZSP were either applied topically to the oral tumor lesions or fed orally at varying dosages to animals with oral tumors for 18 weeks. Tumor volume was measured by histopathological examination. Tumor cell proliferation was evaluated by counting BrdU labeled cells and by Western blotting for mitogen-activated protein kinase (MAPK) protein levels. The protein levels of apoptosis marker Caspase-3 and regulator Bcl-2 protein were also measured by Western blotting. RESULTS: Topical application of DMBA to the left pouch of hamsters induced oral tumor formation. Animals treated with DMBA showed a loss in body weight while animals treated with ZSP maintained normal body weights. Both the ZSP n-butanol fraction and water fraction significantly reduced tumor volume by 32.6% (P < 0.01) and 22.9% (P < 0.01) respectively. Topical application of ZSP also markedly decreased the BrdU-positive cell numbers in oral tumor lesions and reduced the expression level of MAPK. In addition, ZSP promoted tumor cell apoptosis by increasing Caspase-3 expression but decreasing Bcl-2 protein production. CONCLUSION: The n-butanol and water fractions of ZSP are effective at inhibiting tumor cell proliferation and stimulating apoptosis in oral cancer suggesting that these fractions have chemopreventive effects on DMBA induced oral carcinogenesis.

Relationship between nonalcoholic fatty liver disease and metabolic syndrome.

OBJECTIVE: The aim of this study was to investigate the prevalence of nonalcoholic fatty liver disease (NAFLD) and metabolic syndrome (MS) in subjects who underwent a routine health checkup. We intended to establish a clinical association between NAFLD and MS as well as to compare the diagnostic criteria of MS based on the definitions set forth by the International Diabetes Federation (IDF), the US National Cholesterol Education Program Adult Treatment Panel III (2001) (NCEP/ATP-III) and the Metabolic Syndrome Study Group of Chinese Diabetes Society (CDS). METHODS: Weight, height, waist circumference, hip circumference, percentage of body fat, blood pressure and ultrasound of liver were performed on subjects undergoing routine health checkup. Serum triglyceride, total cholesterol, high density lipoprotein cholesterol and fasting plasma glucose level were measured. RESULTS: A total of 2394 subjects were included in this analysis and 437 had NAFLD. The prevalence of MS in the whole sample according to IDF, NCEP/ATP-III and CDS definitions was 11.11%, 8.48% and 5.30%, respectively. The total degree of agreement between IDF, NCEP/ATP-III and CDS definition was 87.76%. The prevalence of MS in NAFLD subjects is much higher than that in non-NAFLD subjects. The prevalence of NAFLD in MS subjects is also much higher than that in non-MS subjects. CONCLUSION: The prevalence of MS varied depending on the diagnostic criteria used. NAFLD was strongly associated with the MS, although it remains unknown whether NAFLD is a cause or effect of MS.

[Comparison of two nonalcoholic hepatocellular steatosis models].

OBJECTIVE: To compare two models of nonalcoholic hepatocellular steatosis. METHODS: HL-7702 cells were incubated with a mixture of of unsaturated oleate acid or 50% fetal bovine serum to induce fat-overloading. Significant fat accumulation was documented by Oil Red O staining , and intracellular triglyceride levels was detected by triglyceride enzymatic assay. RESULTS: The results showed that both 0.5 mmol/ml oleate acid and 50% FBS were able to induce nonalcoholic hepatocellular steatosis. CONCLUSION: A nonalcoholic hepatocellular steatosis was induced by 0.5 mmol/ml oleate acid.

[Expression of survivin, caspase-3 in oral precancerous lesions and oral squamous-cell carcinoma].

OBJECTIVE: To investigate the roles of surviving and caspase-3 in the development of oral cancer. METHODS: Archival tissue sections of 17 oral squamous cell carcinoma (OSCC), 28 oral leukoplakia with dysplasia, 10 normal oral mucosa were obtained from Capital Medical University School of Stomatology for immunohistochemical staining of markers of survivin and caspase-3. The cell apoptosis was detected with terminal deoxynucleotidyl transferase-mediated nucleotide shift enzyme (TdT) mediated d-UTP end labeling (TUNEL). Positively stained cells were counted and analyzed statistically to determine potential relationship between survivin, caspase-3 and cell apoptosis. RESULTS: The expression of survivin was faint or negative in normal epithelial cells. The average positive rate of survivin was (1.05 ± 1.21)% in control group and (21.89 ± 10.45)% in OSCC. Caspase-3 was expressed in all the normal mucosa,but it obviously down-regulated in dysplasia and OSCC. The apoptosis index (AI) decreased from (0.89 ± 0.46)% in normal mucosa to (0.21 ± 0.12)% in OSCC. CONCLUSIONS: Both survivin and caspase-3 are associated with carcinogenesis of the oral mucosa. Survivin may restrain cell apoptosis by inhibiting caspase-3.