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A pure mesoporous SrTiO3 with a honeycomb pore structure is synthesized by the sol-gel method and applied to catalyze transesterification of palm oil with methanol for the biodiesel production. The catalyst is characterized by XRD, CO2/NH3-TPD, N2 adsorption-desorption, SEM-EDX, Raman and XPS to reveal its catalytic performances. The highest FAME yield of 93.14% is achieved in transesterification with the molar ratio of methanol to oil of 15:1 and catalyst concentration of 6 wt% at 170 C for 3 h. Besides, the catalyst is highly tolerant of FFAs and moisture, where the FAME yields of 83.80% and 86.50% are achieved even with the oleic acid and water addition of 10 wt% and 5 wt%. Meanwhile, the catalyst is found to be an effective catalyst for the simultaneous esterification and transesterification. The molecular simulation results show that the Ti sites are more easily attacked by FFAs and the Sr active sites are thus retained for the adsorption of methanol to catalyze transesterification, which explains the bifunctionality of the catalyst.

本研究采用密度泛函理论（DFT）研究了在γ-Fe2O3表面HCl对Hg0的吸附和催化氧化的作用机制。构建了Hg0、HCl、HgCl和HgCl2在γ-Fe2O3(001)表面的吸附模型，分析了HCl对γ-Fe2O3表面催化氧化Hg0的作用机理，并通过反应路径的能量分布测定，研究了γ-Fe2O3表面Hg0的氧化过程。结果表明，Hg0倾向于化学吸附在γ-Fe2O3(001)表面Feoct位。HCl在催化剂表面进行解离吸附，形成吸附态Cl和羟基，从而促进Hg0的吸附。HgCl以分子形式化学吸附在γ-Fe2O3(001)上，并作为Hg0氧化过程的中间体。HgCl2倾向在γ-Fe2O3表面上的平行吸附。同时，HCl在γ-Fe2O3(001)上氧化Hg0遵循L-H机理，即化学吸附的Hg0与解离吸附的HCl反应，且HCl对Hg0的非均相氧化通过两步反应途径进行，即Hg0 (ads)→HgCl(ads)→HgCl2(ads)。

A molecular modeling based on the density functional theory (DFT) and the transition state theory (TST) was performed to investigate the influence of biomass gas CO on the N2O decomposition catalyzed by CaO during reburning in the circulating fluidized bed boiler. The model for N2O adsorption onto the CaO(100) surfaces were constructed; and the processes of the N2O decomposition on the CaO(100) surface and the surface recovery of CaO(100) were investigated. The results illustrate that the energy barrier of N2O decomposition on the CaO(100) surface is much lower than that in homogeneous case, and CaO is therefore able to catalyze the N2O decomposition. The atomic O from N2O decomposition can poison the active sites O atom on the CaO(100) surface, while biomass gas CO can promote the regeneration of the active sites on the surface of CaO(100), which is beneficial for CaO to catalyze the N2O removal.

Background Circulating exosomal microRNAs are reflective of the characteristics of the tumor, are valuable biomarkers in different types of tumors, and play important roles in tumor progression and metastasis. The purpose of this study was to investigate the circulating exosomal microRNAs miRNA-21 and miRNA-210 as novel biomarkers for patients with pancreatic cancer (PC).Methods Serum exosomal microRNAs were extracted from the serum of PC and chronic pancreatitis (CP) patients using an RNA Isolation kit. To identify the exosomes in the serum, we used transmission electron micrographs for the crystalline structure, western blotting, and NanoSight for exosomal markers and nanoparticle characterization. The relative expression levels of exosomal microRNAs were quantified using quantitative PCR and compared between PC and CP patients.Results A total of 40 serum samples (30 PC and 10 CP) were collected. The expression levels of both exosomal miRNA-21 and miRNA-210 were obviously higher in PC patients compared with those in CP patients (both P0.05). Exosomal miRNA-21 and miRNA-210 were related to tumor stage, as well as other factors. The diagnostic of exosomal miRNA-21 and miRNA-210 levels was 83% and 85%, respectively. Furthermore, when combining the expression of exosomal miRNA with serum CA19-9, the accuracy increased to 90%.Conclusions We herein identified that the serum exosomal miRNAs miRNA-21 and miRNA-210 may be of value as potential biomarkers and therapeutic targets for the diagnosis and treatment of PC.

Tamoxifen (TMX) is an antiestrogen drug that is used in the treatment and prevention of all stages of estrogen-dependent breast cancer. Adverse effects of TMX include hepatotoxicity. In this study, we investigated the therapeutic effects of osthole, isolated from medicinal plants especially Fructus Cnidii, on TMX-induced acute liver injury in mice. Mice were injected with osthole (100 mg/kg, ip) or vehicle, followed by TMX (90 mg/kg, ip) 24 h later. We showed that a single injection of TMX-induced liver injury and oxidative stress. Pretreatment with osthole attenuated TMX-induced liver injury evidenced by dose-dependent reduction of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities. Pretreatment with osthole also blunted TMX-induced oxidative stress, evidenced by significant increase of reduced glutathione (GSH) as well as reduction of malondialdehyde (MDA) and hydrogen peroxide (H(2)O(2)). Consistently, osthole significantly enhanced the expressions of antioxidant genes (GPX1, SOD2, GCL-c, and G6pdh), but suppressed those of pro-oxidant genes (NOX2 and ACOX). Furthermore, osthole inhibited the production of inflammatory cytokines, reduced the metabolic activation of TMX, and promoted its clearance. We further revealed that osthole elevated hepatic cAMP and cGMP levels, but inhibition of PKA or PKG failed to abolish the hepatoprotective effect of osthole. Meanwhile, prominent phosphorylation of p38 was observed in liver in response to TMX, which was significantly inhibited by osthole. Pretreatment with SB203580, a p38 inhibitor, significantly attenuated TMX-induced increase of ALT and AST activities, reduced oxidative stress, and reversed the alterations of gene expression caused by TMX. Moreover, pretreatment with L-buthionine sulfoximine (BSO), an inhibitor of GSH synthesis, partly reversed the effect of osthole on TMX-induced liver injury. Consistently, pretreatment with N-acetyl-L-cysteine (NAC) significantly attenuated TMX-induced increase in ALT and AST activities. Notably, both BSO and NAC had no detectable effect on the phosphorylation levels of p38. Collectively, our results suggest that osthole prevents TMX hepatotoxicity by suppressing p38 activation and subsequently reducing TMX-induced oxidative damage.

Background Borax, a boron compound, which is becoming widely recognized for its biological effects, including antioxidant activity, cytotoxicity, and potential therapeutic benefits. However, the specific molecular mechanisms underlying borax-induced anti-tumor effect still remain to be to further elucidated. MicroRNAs (miRNAs) may play key roles in cellular processes including tumor progression, cell apoptosis and cytotoxicity. Thus, this study aimed to investigate, whether miRNAs were involved in the borax-mediated anti-tumor effect using miRNA profiling of a human liver cancer cell line (HepG2) using gene-chip analysis.Methods Total RNA was extracted and purified from HepG2 cells that were treated with 4 mM borax for either 2 or 24 h. The samples underwent microarray analysis using an Agilent Human miRNA Array. Differentially expressed miRNAs were analysed by volcano plot and heatmap, and were validated using real-time fluorescent quantitative PCR (qPCR).ResultsAmong this, 2- or 24-h exposure to borax significantly altered the expression level of miRNAs in HepG2 cells, 4 or 14 were upregulated and 3 were downregulated compared with the control group, respectively (≥2-fold; P

Circulating exosomal microRNAs (ex-miRNAs) are reflective of the characteristics of the tumor and are valuable biomarkers in different types of tumor. In addition, miRNAs serve important roles in tumor progression and metastasis. The present study aimed to investigate the circulating ex-miRNA-21 and miRNA-210 as novel biomarkers for patients with pancreatic cancer (PC). For this purpose, serum ex-miRNAs were extracted from the serum of patients with PC (n=30) and chronic pancreatitis (CP) (n=10) using an RNA isolation kit. For exosome identification in serum, transmission electron micrographs were used to determine crystalline structure, western blotting was used to identify exosomal markers, and NanoSight was used for nanoparticle characterization. The relative expression levels of ex-miRNAs were quantified using quantitative PCR and compared between patients with PC and CP. The expression levels of both ex-miRNA-21 and miRNA-210 were significantly higher in patients with PC compared with patients with CP (both P0.05). ex-miRNA-21 and miRNA-210 were associated with tumor stage, as well as other factors. The diagnostic potential of ex-miRNA-21 and miRNA-210 levels was 83 and 85%, respectively. In addition, when ex-miRNA and serum carbohydrate antigen 19-9 expression levels were combined, the accuracy increased to 90%. The present study identified that serum ex-miRNAs, miRNA-21 and miRNA-210 may be of value as potential biomarkers and therapeutic targets for the diagnosis and treatment of PC.

Borax is a boron compound that is becoming widely recognized for its biological effects, including lipid peroxidation, cytotoxicity, genotoxicity, antioxidant activity and potential therapeutic benefits. However, it remains unknown whether exposure of human liver cancer (HepG2) cells to borax affects the gene expression of these cells. HepG2 cells were treated with 4 mM borax for either 2 or 24 h. Gene expression analysis was performed using Affymetrix GeneChip Human Gene 2.0 ST Arrays, which was followed by gene ontology analysis and pathway analysis. The clustering result was validated using reverse transcription-quantitative polymerase chain reaction. A cell proliferation assay was performed using Celigo Image Cytometer Instrumentation. Following this, 2- or 24-h exposure to borax significantly altered the expression level of a number of genes in HepG2 cells, specifically 530 genes (384 upregulated and 146 downregulated) or 1,763 genes (1,044 upregulated and 719 downregulated) compared with the control group, respectively (≥2-fold; P

Rapid growth of residual tumors can occur as a result of their recurrence and progression. The present study aimed to investigate the expression of hypoxia inducible factor-2 subunit α (HIF-2α), vascular endothelial growth factor A (VEGFA), erythropoietin-producing hepatocellular A2 (EphA2) and angiogenesis in residual hepatocellular carcinoma (HCC), following treatment with high-intensity focused ultrasound (HIFU) ablation, in order to investigate the association between protein expression and tumor recurrence and growth. Athymic BALB/c (nu/nu) mice were subcutaneously inoculated with the HCC cell line HepG2, in order to create xenograft tumors. Approximately 30 days post-inoculation, eight mice were treated with HIFU, whereas eight mice received no treatment and acted as the control group. Residual tumor tissues were obtained from the experimental groups after one month. Levels of HIF-2α, VEGFA, EphA2 and cluster of differentiation 31 (CD31) expression was measured by immunohistochemical staining. CD31-positive vascular endothelial cells were counted to calculate microvascular density (MVD), and western blot analysis was performed to determine levels of HIF-2α, VEGFA, and EphA2 protein. It was found that the expression levels of HIF-2α, VEGFA, EphA2, and MVD proteins in residual HCC tissues were significantly higher than in the control group tissues (P

Eddy current sensor with online non-contact measurement, no coupling medium and high sensitivity etc, is widely used in engineering. In this paper, based on the eddy current testing principle, the eddy current sensor is modeled in ANSYS software to complete the optimization design. The article research on the method of flaw recognition after extracting the detection signal features and analysis the impact of the flaw size on the detection signal, so as to provide a theoretical method of qualitative detection in the practical application.

Inverse dynamics problem of large-displacement motion simulator is solved by Roberson-Wittenburg method. Simulation graphs plotted by matlab prove the validity of solution. This paper can be used in control studies of motion simulator.

In order to study the elastic motion stability of flexible manipulator arm , to compute the maximum dynamic allowable payload , the partial differential equation of elastic motion of the flexible manipulator arm is solved using the method of Laplace transformation , the dynamic model of flexible manipulator arm carried addition mass on its end position is established ,simplified and truncated using Lagrange equation . the state space expression is established with the state variable and control input and output variable designated , the elastic motion stability rule is built upon and simplified using Lyapunov stability theory . The influence of the end position addition mass and articulation rotational inertia of flexible manipulator arm on its elastic motion stability is analyzed using the stability rule , and the dynamic maximum allowable payload of flexible manipulator arm on its end position is computed in order to guarantee its elastic motion stability . this study is important to the design of robot mechanical manipulator and corresponding drive control system .

Cloud storage is an active research domain currently, and how to secure the reliability of data is an important research issue. For the moment, most systems apply the static data replication strategy, which causes a serious waste of storage resources. Considering the user requirements and the factors influenced on data reliability, i.e., the node reliability and Relevant Failure Degree, Data Replication Strategy based on Relevant Failure is provided in this paper. According to the results of the experiments, our strategy reduces the number of data replicas and meets the user requirement of reliability at the same time. Besides, the strategy has a better performance on increasing the utilization of storage resources.

Different cloud services need different resources, how to use the resources efficiently has become one of the hot research topics about cloud computing. In order to improve the utilization of resources in cloud, this paper proposes an automatic cloud service classification method, which uses an artificial neural network to predict the type of service resource requirements, and classifies services based on the predicting result. In this paper, we do classification experiments on three groups of Web services on Web service site. The experiment results show that, the method is effective and can predict the type of resource requirements for Web services automatically.

The potential of using the waste from simultaneous NOx and SO2 purification bio-trickling process to leach copper ore and to make fertilizer was investigated. It was found there were two main exhausted by-products in the purification process: the acidic liquid in desulfurization tower and the alkalescent liquid in denitrogenation tower. Through operation of leaching the oxide ore sample containing 2.58% copper by the acidic liquid, the effective grade of the metal to be extracted reached 28.37% by weight. With adding proportional dose of ammonia into the alkalescent liquid or the acidic liquid and going through evaporation and concentration, crystal products of ammonium sulfate and ammonium nitrate were generated, which can be used in fertilizer manufacturing.

The kinematics and dynamic analysis of the large-displacement motion simulator is analyzed and derived in detail. By using MATLAB program, the simulation curves of the derived kinematics and dynamic formula match to the practical situation. Our result will provide the theoretical direction for the further study of the large-displacement motion simulator.

The large-displacement motion simulator which composed by Cartesian coordinate movement Desk and Three-axis turntable was designed in this paper. This Motion simulator can move the working spaces to any position of the space by any posture, which solved the disadvantages of the STEWART platform, the smaller spatial displacement and limited space corner. Kinematic analysis of the large-displacement motion simulator was discussed in this article, and theoretical modeling of the large-displacement motion simulator was presented by KANE equations. This has the theoretical significance for the research of the technology of space motion simulation and docking.

The degree of flexibility of workflow management systems heavily influences the way business processes are executed. Constraint-based models are considered to be more flexible than traditional models because of their semantics: everything that does not violate constraints is allowed. More and more people use declarative languages to define workflow, such as linear temporal logic. But how to guarantee the correctness of the model based on the linear temporal logic is still a problem. This article proposes a way to verify the model based on Büchi automaton and gives the corresponding algorithms. Thus the verification of declarative workflow based on the linear temporal logic is solved.

To realize the efficient and stable real-time monitoring and intelligent management of the urban public lighting, the remote monitoring system is developed. The system is composed of monitoring center and monitoring terminals, and realizes network connection via the advanced remote wireless communication technology GPRS. It uses TI Company’s MSP430 processor chip as the monitoring terminal controller, which integrates automatic control, data acquisition, communication and other technologies and has such functions as monitoring, remote control, anti-electricity theft, remote meter reading and communication. It’s proved by practice that the designed controller features reliable running, sound real-time performance and low cost, and has a broad and bright application prospect. The monitoring and management of public lighting is a typical sector and important part of the civil work. Due to the continuous development of urban construction and ever-enlarging lighting coverage, the traditional lighting management methods can not realize centralized monitoring, have poor real-time performance and cost lots of human and material resources; thus, can not satisfy the requirements of energy saving and efficiency improvement[1]. GPRS (General Packet Radio Service), the wireless packet exchange technology based on the second generation mobile communication system GSM, is very suitable for transmitting non-continuous, unexpected and small sets of street lamp monitoring data. Also, quick & easy log-on, real-time online, high-speed transmission, sound economical efficiency and many other advantages make GPRS become the first choice for remote measurement and control system[2]. Therefore, the development of GPRS-based public lighting remote monitoring system becomes a necessity. The designed monitoring system in this article is a typical distributed monitoring and data acquisition system integrating computer technologies, modern communication technologies and automatic control technologies. It conducts centralized monitoring and control on the cabinet transformer substations, transformer cabinets, control cabinets and other slave monitoring systems of the public lighting such as street lamps and landscape lamps of the city, to realize the real-time, remote monitoring and intelligent management of public lighting and ensure the efficient, all-weather running and on-demand, energy-saving lighting.

A quantitative analysis method based on near infrared (NIR) spectroscopy was developed for determining the azithromycin content and its degradation product impurity (decladinosylazithromycin) in azithromycin for injection. Two quantitative models were obtained by evaluating 18 laboratory samples and 44 commercial samples formulated as hydrochlorate, phosphate, lactate and citrate salts. The samples had an azithromcyin content ranging from 74.2% to 91.0% (w/w) and decladinosylazithromycin ranging from 0.1% to 7.7% (w/w). The root mean square error of cross-validation for the azithromycin model and decladinosylazithromycin model were 1.54% and 0.49%, respectively. The estimated limit of detection and limit of quantification for the decladinosylazithromycin calibration were about 1.2% and 4.1% (w/w), respectively. In addition, the quantitative models were validated in terms of specificity, linearity, accuracy, repeatability and intermediate precision, according to the International Conference on Harmonisation guidelines, by evaluating the characteristics of the NIR spectra. The results showed that the models were satisfactory. Our results demonstrated that a universal quantitative model based on NIR diffuse reflectance spectroscopy could be used as a quick and reliable method for quality control of low-dose impurities in pharmaceutical drugs.

Hepatocellular carcinoma (HCC) is considered as a disease of dysfunction of the stem cells. Studies on stem cells have demonstrated that Oct4 plays a pivotal role in embryo regulation. In order to understand the role of Oct4 in HCC and the relationship among Oct4 and wnt/β-catenin and TGF-β signal pathways, we have detected the expression of Oct4, Nanog, Sox2, STAT3 as well as the genes in wnt/β-catenin, and TGF-β families in HCC cell lines and in tumor specimens from HCC patients. The authors found that Oct4 was expressed in all of the four HCC cell lines and the tumor specimens from HCC patients. Some other genes were also expressed in them with different level including Nanog, Sox2, STAT3 and TCF3, wnt10b, β-catenin, ELF, Smad3 and Smad4. The ability of the clone formation and migration of the HepG2 decreased after Oct4 was knockdowned. Silencing of Oct4 and TCF3 in HCC cell line HepG2 revealed that there were complicated relationships among Oct4, wnt/β-catenin family and TGF-β family genes. Knockdowning Oct4 reduced the expression of TGF-β family genes ELF, Smad3, Smad4 and wnt/β-catenin family genes, wnt10b, and β-catenin but increased TCF3. In reverse, knockdowning TCF3 led to the increased expression of Oct4 and TGF-β family genes. In conclusion, the expression of Oct4 in HCC may play an important role as in stem cell. Because Oct4 improves not only the function of wnt/β-catenin, but also the TGF-β signal pathways, the significance of its expression in HCC might be more complicated than we evinced before.

Borax, a boron compound and a salt of boric acid, is known to inhibit the growth of tumor cells. HepG2 cells have been shown to be clearly susceptible to the anti-proliferative effects of borax. However, the specific mechanisms regulating this effect are poorly understood. This study aimed to investigate the pathways underlying the growth inhibition induced by borax in HepG2 cells. The effects of borax on HepG2 cell viability were characterized using MTT. Apoptosis was also verified by annexin V/propidium iodide staining. JC-1 dye and western blotting techniques were used to measure mitochondrial membrane potential and p53, Bax, and Bcl-2 protein expression, respectively. Relevant mRNA levels were measured by qRT-PCR. Borax inhibited the proliferation of HepG2 cells in a time- and dose-dependent manner in vitro. The apoptotic process triggered by borax involved the upregulation of p53 and Bax and the downregulation of Bcl-2, which was confirmed by a change in the mitochondrial membrane potential. These results elucidate a borax-induced apoptotic pathway in HepG2 cells that involves the upregulation of p53 and Bax and the downregulation of Bcl-2.

Normal hepatocytes express connexin32 (Cx32), which forms gap junctions at cell‑cell contact areas. The aim of the present study was to investigate whether Cx32 mediates the cell death‑inducing effects of ultrasound microbubbles carrying the herpes simplex virus thymidine kinase (HSV‑TK) suicide gene against hepatocellular carcinoma cells in vitro and in vivo. HepG2 cells were exposed to different concentrations of trans‑retinoic acid (ATRA) in culture, to evaluate the intrinsic antitumor effect of ATRA. Detailed in‑vitro and in‑vivo investigations on the antitumor effects of ATRA via Cx32 mediation were performed, and the possible underlying mechanisms of action of the compound were then examined. The gene expression of HSV‑TK transfected by ultrasound wave irradiation in the HepG2 cells was quantified using reverse transcription‑quantitative polymerase chain reaction analysis. The effects on cell death were assessed using an MTT assay. The protein expression levels of Cx32 in ATRA‑untreated or ATRA‑treated tissues were quantified by immunohistochemical analysis and Western blot assays. The HSV‑TK gene was successfully transfected into the HepG2 cell using ultrasound wave irradiation, and was stably expressed. Compared with the other groups, the HSV‑TK gene group treated with ATRA exhibited an increased number of apoptotic cells (P

The title compounds were obtained from the reactions of copper or silver monohalides with the bidentate bis(diphenylphosphino)methane (dppm) ligand at room temperature in a mixed solvent. Single-crystal X-ray diffraction analyses indicate that both compounds crystallize in a monoclinic system but in different space groups. The structures are characterized by a trinuclear [M3I2(dppm)3]+ cation with a trigonal-bipyramid [M3(μ 3-I)2] core. In agreement with the geometric characteristics of the M3 triangles, 31P NMR spectra exhibit a single peak for the [Cu3] cluster but a double-peak for the [Ag3] cluster. Preliminary optical studies by UV/Vis and emission techniques show major absorption shoulders at ∼286 nm for Cu3I2(dppm)3·I and ∼254 nm for Ag3I2(dppm)3·I, but no luminescence in the non-degassed MeCN solution at 298 K. The structures, bonding, electronic excitations and emissions are discussed based on relativistic density functional theory calculations.

The title compound, C6H6N4S4, is formed through the thionato S—S bonding of parent 2-mercapto-5-methyl-1,3,4-thia­diazole mol­ecules, following the deprotonation of thiol groups in a mixed solvent. The title compound crystallizes in the monoclinic system, space group C2/c. The S—S distance is 2.028 (1) A, typical of a single bond. The two 1,3,4-thia­diazo­le rings in the mol­ecule each remain planar, with a dihedral angle of 70.5 (1) A, and are related by a twofold rotation axis through the middle of the S2—S2 bond. The geometric parameters for the parent ligand are also reported, to demonstrate the influence of deprotonation on the ligand dimensions.

To investigate the expression of Oct4, Sox2, Nanog, SMO, beta-Catenin and Wnt5b mRNA in four hepatocellular carcinoma cell lines of SMMC-7721, Bel-7402, HepG2, MHCC-97 and normal hepatocellular cell line of L02, and to compare the response of these cell lines to all-trans retinoic acid.RT-PCR was used to detect expression of Oct4, Sox2, Nanog, SMO, beta-Catenin and Wnt5b mRNA in four hepatocellular carcinoma cell lines and normal hepatocellular cell line. Real time-PCR was used to quantify the expression of the genes.There are different levels of expression of the stem cell-related gene in hepatocellular carcinoma cell lines and control cell line (P less than 0.05). There are significant differences in HepG2 and L-02 for the response to all-trans retinoic acid (P less than 0.05).The stem cell-related genes are differentially expressed in different hepatocellular carcinoma cell lines.

Cryotherapy has been shown to be an important therapeutic alternative to surgery in the treatment of hepatocellular carcinoma (HCC). Here, the influence of cryo-chemotherapy on HCC was examined in vitro using the human HCC cell line Bel-7402, a drug-resistant HCC cell line originating from Bel-7402 cells (Bel-7402/R), as well as two control cell lines, the HCC cell line SMMC-7721 and a colorectal tumor cell line HIC-251. Cells were treated with either exposure to different freezing temperatures (ranging from -15 to -80 degrees C for 20 min), exposure to sub-lethal concentrations of anticancer chemotherapy drugs or a combination of cryotherapy and chemotherapy. Cell viability and apoptosis under each condition were investigated. We found that the combined treatment resulted in increases in both cell death and apoptosis compared to either treatment alone. The increased level of apoptosis observed in Bel-7402 cells after cryo-chemotherapy was inhibited in the presence of caspase inhibitors. Furthermore, Bax expression was increased 2- to 3-fold in cells exposed to the combination treatment compared with cells treated by freezing or drugs alone. In contrast, Bcl-2 levels remained constant. Although Bel-7402/R cells originated from the Bel-7402 cell line, they were more sensitive to the freezing procedure than the parental cell line. The level of Bax expression in Bel-7402/R cells was also higher than that observed in the parental cell line. In addition, we found that Bel-7402/R cells had lower levels of survivin mRNA than the parental Bel-7402 cells, in both untreated and treated cells. In conclusion, our data show that in HCC cells, apoptosis induced by cryotherapy can be synergistically enhanced using anticancer drugs.

The simultaneous desulfurization of 2-mercapto-5-methyl-1,3,4-thiadiazole with CuCl(2) x 2H(2)O via mutual diffusion in solvents results in the isolation of air-stable dark-green crystals of [Cu(H(4)C(3)N(2)S)Cl(2)](n) (approximately 65% yield). The structure is characterized by a unique one-dimensional copper chain bridged by diazine N-N single bonds rather than halogens, in sharp contrast with the halide bridging mode in conventional copper halide coordination polymers. Each Cu(II) ion shows a square planar coordination geometry featuring a strong Jahn-Teller distortion, as also supported by EPR data. The phase follows a Curie-Weiss paramagnetic behavior over 6-300 K. However, the intrachain antiferromagnetic interaction is evident (-2J = 21.1 cm(-1)). Such magnetic coupling is related to the interplay between the Cu(II)-d(x2-y2) and diazine N-N p-orbitals.