bluuebunny/crossref_metadata_2025 huggingface dataset:
Positive and negative effects of livestock grazing on plant diversity of Mongolian nomadic pasturelands along a slope with soil moisture gradient
Authors: Fujita Noboru , Amartuvshin Narantsetsegiin , Yamada Yasuhiro , Matsui Kiyoshi , Sakai Shoko , Yamamura Norio
Published: August 2009

To examine different effects of herbivorous large mammals’ grazing pressure on plant diversity along a slope in a Mongolian nomadic pasture, we compared species richness, Simpson’s index of diversity, and the total plant coverage of plants between protected pasture from livestock grazing and grazed pasture on the near ridge, upper slope, lower slope, foot slope and valley bottom. The species richness and Simpson’s index of diversity decreased and the total coverage increased downwardly with increase in pasture soil moisture along the slope. The species richness of the protected pasture decreased, changed little, and increased on the near ridge and the upper slope, the lower slope and the foot slope, and the valley bottom, respectively. Simpson’s index of diversity of the protected pasture decreased compared with the grazed pasture only on the valley bottom. The total coverage became lower in the grazed pasture. As the reason for our results, we discuss positive and negative effects of livestock grazing on the species diversity of plants. The positive effect is shown on the valley bottom, where soil moisture and plant growth becomes high with the total coverage over 100%, due to relaxing indirectly the competitive exclusion among plants due to the grazing of dominant plants. The negative effect is obtained on the near ridge and the upper slope, where the soil moisture and the plant growth are low, because of elimination of some plants from the pasture by direct grazing damage.
Pasture height distribution of grazed tropical native grammas in Veracruz State, Mexico
Authors: Castillo Epigmenio , Valles Braulio , Jarillo Jesús , Ocaña Eleazar
Published: August 2009

Pasture height measurement and its statistical distribution have been neglected topics in tropical pasture research. Thus, the objective of this study was to fit the single normal (SN), double normal (DN), log normal (LN), gamma (GM) and Weibull (WB) models to relative frequency distributions of pasture height (PHT, cm) of native gramma pastures of the Mexican humid tropics. PHT measurements were done in a study where fixed rotational grazing was used (3‐day grazing/27‐day rest paddock–1) at three stocking rates of two, three and four F1 (Holstein × Zebu) cows ha−1. Two paddocks per stocking rate were used. Approximately 400 PHT measurements were done on each paddock, before (22 times) and after (23 times) grazing. The models were fit by least squares, using the Marquardt–Lavenberg iteration. The Akaike’s information criterion corrected (AICc) was used to select the model with the best fit. Before grazing, the models with the best fit were the DN and the GM, and after grazing, the best fit was shown by the DN and the LN. With respect to stocking rate, the best models were: LN and GM for two cows ha−1; DN and LN for three cows ha−1; and DN for four cows ha−1. However, the differences between the AICc values of the model with the best fit and the second in rank were small; thus, either could fit the data equally well. In conclusion, PHT of native gramma pastures did not distribute normally, and either the double normal or the log normal models can be used as means to describe the PHT frequency distributions of this type of pastures.
Effects of year and location on the nutritive value in the first crop of timothy (Phleum pratense L.)
Authors: Ashikaga Kazunori , Tamaki Hiroyuki , Sato Narichika , Tanaka Tsuneki , Deguchi Kenzaburo , Iida Kenji , Sato Koichi
Published: August 2009

Timothy (Phleum pratense L.) is the most important perennial forage grass grown in Hokkaido, Japan. Hence, the improvement of its nutritive value by breeding could be effective in enhancing animal productivity in the region. Effective improvement of the nutritive value of the grass requires a study on how the relative genotype ranking of the nutritive value changes in different environments. The objective of the present study was to investigate the magnitude of genotype × year interaction (G × Y) and genotype × location interaction (G × L) in the nutritive value of timothy. We grew 15 early‐maturing clones of timothy in Kunneppu in 2004 and 2005 to estimate G × Y and 11 early‐maturing clones in Kunneppu and Nakashibetsu in 2007 to estimate G × L, and analyzed the first crops by near‐infrared reflectance spectroscopy. The ratio of low‐digestible fiber content to organic cell wall content (Ob/OCW), Ob content and water‐soluble carbohydrate (WSC) content were significantly correlated between the 2 years and between the two locations, with non‐significant effects of G × Y and G × L. We conclude that the relative ranking of genotypes in different years and at different locations should be consistent for the traits and that selection for the traits in a single environment should be useful in effective improvement of the nutritive value of timothy.
Induction of tetraploid ruzigrass (Brachiaria ruziziensis) plants by colchicine treatment of in vitro multiple‐shoot clumps and seedlings
Authors: Ishigaki Genki , Gondo Takahiro , Suenaga Kazuhiro , Akashi Ryo
Published: August 2009

Tetraploid plants of ruzigrass (Brachiaria ruziziensis) have been obtained by colchicine treatment of in vitro multiple‐shoot clumps and germinated seedlings. Multiple‐shoot clumps were induced and maintained on MS basal medium with 0.5 mg L−1 2,4‐dichlorophenoxyacetic acid (2,4‐D) and 2.0 mg L−1 6‐benzylaminopurine (BAP) according to a previous report. The colchicine treatment consisted of culturing multiple‐shoot clumps on MS basal medium containing 0.0125–0.1% colchicine for 12 and 48 h. Surviving multiple‐shoot clumps were regenerated on MS basal medium containing 2.0 mg L−1 BAP. The ploidy level of plants after colchicine treatment was determined by flow cytometry. Eight tetraploid plants were obtained from multiple‐shoot clumps treated with 0.1% colchicine for 12 h. This treatment was identified as the optimum treatment and resulted in the highest frequency (28.6%) of tetraploid plants among the treatments tested on multiple‐shoot clumps. Five tetraploid plants (31.3%) were obtained when seedlings were treated with 0.1% colchicine for 3 h. Although higher concentrations of colchicine and longer durations of colchicine treatment reduced the survival rate of the explants, such treatments increased the frequency of tetraploid plants. A total of 23 tetraploid plants were obtained from 900 different colchicine‐treated multiple‐shoot clumps, and a total of five tetraploid plants were obtained from 300 colchicine‐treated seedlings. Cytological analysis affirmed the results of flow cytometry. Significant differences in leaf blade stomata were observed between diploid and tetraploid ruzigrass.
Single‐ and Multilayered Interphases in SiC/SiC Composites Exposed to Severe Environmental Conditions: An Overview
Authors: Naslain Roger R. , Pailler René J.‐F. , Lamon Jacques L.
Published: August 2009

Pyrocarbon (PyC), the common interphase for SiC/SiC, is not stable under severe environmental conditions. It could be replaced by boron nitride more resistant to oxidation but poorly compatible with nuclear applications. Other materials, such as ternary carbides seem promising but their use in SiC/SiC has not been demonstrated. The most efficient way to improve the behavior of PyC interphase in severe environments is to replace part of PyC by a material displaying a better compatibility, such as SiC itself. Issues related to the design and behavior of layered interphases are reviewed with a view to demonstrate their interest in high‐temperature nuclear reactors.
Microstructure–Property Relationships for Low‐Voltage Varistors
Authors: Pan Wen‐Hsuan , Kuo Shu‐Ting , Tuan Wei‐Hsing , Chen Huey‐Ru
Published: August 2009

The low‐voltage varistors with various layer thickness are prepared by laminating thin ZnO‐based ceramic layers and AgPd electrodes together. The breakdown voltage dose not exhibit linear relationship with layer thickness. It is due to that the presence of the AgPd electrodes enhances the growth of ZnO grains. As some ZnO grains are large enough to touch the upper and lower electrodes, the breakdown voltage of the varistor is only 3.7 V. The nonlinear coefficient of the low‐voltage varistor is 33. Such nonlinear current–voltage behavior is mainly contributed by the interface between the AgPd electrode and ZnO grains.
Spectroscopically and spatially resolved optical line emission in the Superantennae (IRAS 19254-7245)
Authors: Bendo George J. , Clements David L. , Khan Sophia A.
Published: August 2009

We present Visible Multi-Object Spectrograph integral-field spectroscopic observations of the ultraluminous infrared galaxy (ULIRG) pair IRAS 19254−7245 (the Superantennae). We resolve Hα, [N ii], [O i] and [S ii] emission both spatially and spectroscopically, and separate the emission into multiple velocity components. We identify spectral line emission characteristic of star formation associated with both galaxies, broad spectral line emission from the nucleus of the southern progenitor and potential outflows with shock-excited spectral features near both nuclei. We estimate that ≲10 per cent of the 24 μm flux density originates from star formation, implying that most of the 24 μm emission originates from the active galactic nuclei in the southern nucleus. We also measure a gas consumption time of ∼1 Gyr, which is consistent with other measurements of ULIRGs.
Disubstituted 4(3H) Quinazolones: A Novel Class of Antitumor Agents
Authors: Srivastava Vikas , Srivastava Anand Mohan , Tiwari Anjani K. , Srivastava Rakesh , Sharma Rajbala , Sharma Himanshu , Singh Vinay K.
Published: August 2009

A series of disubstituted 4(3H) quinazolines were designed for potential application in tumors. Firstly, N‐benzoyl anthranilic acid is formed, which undergoes cyclization in the presence of pyridine. Subsequently, nucleophilic attack by semicarbazide on the carbonyl carbon gives 2‐substituted 3‐carbamido 4(3H) quinazolones, which gives final compound with appropriate substitution. The final as well as intermediate products were confirmed by NMR, FT‐IR, and mass spectrometry. In vitro toxicity was performed with different cell lines and showed that the connection of hydrophilic styryl to quinazoline moiety increases its efficacy.
In Silico Screening for Non‐nucleoside HIV‐1 Reverse Transcriptase Inhibitors Using Physicochemical Filters and High‐Throughput Docking Followed by In Vitro Evaluation
Authors: Bustanji Yasser , Al‐Masri Ihab M. , Qasem Ahmad , Al‐Bakri Amal G. , Taha Mutasem Omar
Published: August 2009

Reverse transcriptase, being the pivot in human immunodeficiency virus replication, is one of the most attractive targets for the development of new antiretroviral agents. We applied a virtual screening workflow based on a combination of physicochemical filters with high‐throughput rigid molecular docking to discover novel efficient lead scaffolds for human immunodeficiency virus type 1 reverse transcriptase inhibition. In our protocol, different filters were employed to enrich the lead‐likeness and improve the ligands efficiency of the filtered compounds. Out of the 238 819 compounds included in the Natinal Cancer Institute database, 500 virtual screening hits were retrieved employing filter and fred (molecular docking engine) softwares. Four compounds from the 20 highest ranking scored hits tested positive in human immunodeficiency virus type 1 reverse transcriptase using non‐radioactive colorimetric assay method. These results demonstrate that our virtual screening protocol is able to enrich novel scaffolds for human immunodeficiency virus type 1 reverse transcriptase inhibition that could be useful for drug development in the area of acquired immune‐deficiency syndrome treatment.
A New Series of 1,3‐Dihidro‐Imidazo[1,5‐c]thiazole‐5,7‐Dione Derivatives: Synthesis and Interaction with Aβ(25‐35) Amyloid Peptide
Authors: Campiglia Pietro , Scrima Mario , Grimaldi Manuela , Cioffi Giuseppina , Bertamino Alessia , Sala Marina , Aquino Claudio , Gomez‐Monterrey Isabel , Grieco Paolo , Novellino Ettore , D’Ursi Anna Maria
Published: August 2009

Deposition of senile plaques composed of fibrillar aggregates of Aβ‐amyloid peptide is a characteristic hallmark of Alzheimer’s disease. A widely employed approach in the study of anti‐Alzheimer agents involves the identification of substances able to prevent amyloid aggregation, or to disaggregate the amyloid fibrils through a direct structural interaction with the soluble or aggregated forms of the peptide. Here, we report the synthesis of a set of 1,3‐dihydro‐3,6‐disubstituted‐imidazo[1,5‐c]thiazole‐5,7‐dione derivatives supporting different alkyl, aryl and alkylamine side chains. The ability of these compounds to interact with the Aβ(25‐35) peptide was evaluated using circular dichroism, nuclear magnetic resonance and thioflavin fluorescence spectroscopy. A molecular model for Aβ(25‐35)–ligand interactions was calculated by molecular docking procedures. Our data show that the ability of the synthesized compounds to modify the structural behaviour of Aβ(25‐35) varies as a function of the overall structural features of the ligands rather contributions from specific individual substituents.
One‐Pot Synthesis of Highly Functionalized Seleno Amino Acid Derivatives
Authors: Liu Haixia , Dömling Alexander
Published: August 2009

We herein provide a new and rapid protocol to generate derivatives of seleno amino acid, including methyl selenocysteine, selenomethionine, and selenocystine. Applying the isocyanide‐based multicomponent reaction Ugi‐4C‐5C reaction, we show that each of the commercially available seleno amino acids are good substrate for these reactions and can be used together with complementary oxocomponents and isocyanides to generate highly diverse functionalized selenium‐containing compounds. These compounds might become useful tools for applications in chemical biology to elucidate the role of selenium in biochemistry.
Design, Synthesis, and Docking Studies of Peptidomimetics Based on HER2–Herceptin Binding Site with Potential Antiproliferative Activity Against Breast Cancer Cell lines
Authors: Satyanarayanajois Seetharama , Villalba Stephanie , Jianchao Liu , Lin Go Mei
Published: August 2009

Epidermal growth factor receptor kinase and the related human epidermal growth factor receptor‐2 (HER2, ErbB2) are two growth factor receptors that have implications in cancer. The overexpression or activation of HER2 occurs frequently in breast, ovarian, and lung cancers, making it an important therapeutic target in the treatment of cancer. Blocking HER2‐mediated signaling with antibodies or small molecules has been shown to be effective in inhibiting cell growth. After analyzing the crystal structure of the HER2–herceptin complex, several peptidomimetics (HERP5, 6, and 7) were designed to inhibit HER2‐mediated signaling for cell growth. We have used an in silico screening method to investigate the chemical diversity of the designed compounds. autodock software was used to dock the different analogs of HERP5 and HERP7 with HER2 protein extracellular domain. A total of 53 compounds were docked to HER2 protein, and their binding modes were analyzed in terms of docking energy, hydrogen bonding, and hydrophobic interactions. Compounds that exhibited low‐energy docked structures were chosen for chemical synthesis and biological activity. Two of the compounds (HERP5 and HERP7) exhibited antiproliferative activity, with IC50 values of 0.396 μm and 0.143 μm, respectively, against SKBR‐3 cell lines (breast cancer cell lines) that overexpress HER2 protein.
Which Carbonic Anhydrases are Targeted by the Antiepileptic Sulfonamides and Sulfamates?
Authors: De Simone Giuseppina , Scozzafava Andrea , Supuran Claudiu T.
Published: August 2009

Zonisamide, sulthiame, and topiramate, clinically used antiepileptics are inhibitors of mammalian carbonic anhydrase isoforms I–XIV, indiscriminately inhibiting with variable efficacy all the catalytically active isoforms present in mammals. However, it is not clear which carbonic anhydrase isozymes might be responsible for the anticonvulsant activity of such sulfonamide/sulfamate drugs. We examine here the full inhibition profile against all mammalian carbonic anhydrases of the above antiepileptic drugs together with two investigational, structurally related sulfonamides, one of which is and the other is not an anticonvulsant. No clear‐cut data allow us to propose which are the carbonic anhydrases involved in these processes, but strong carbonic anhydrase II, VII, IX, and XII inhibition, correlated with sufficiently high liposolubility may lead to effective anticonvulsants of this pharmacological class. Therefore, further studies are warranted for better understanding these phenomena. Whether the inhibition of such carbonic anhydrases present in the mammalian brain might be relevant for designing pharmacological agents useful in the management of neurological disorders or for understanding the multifactorial mechanism of action of some of these drugs is a topic which surely deserves further investigations.
Synthesis and Biological Applications of Imidazolium‐Based Polymerized Ionic Liquid as a Gene Delivery Vector
Authors: Zhang Yuanyuan , Chen Xiang , Lan Jingbo , You Jingsong , Chen Lijuan
Published: August 2009

The encouraging results of preliminary toxicological studies on imidazolium‐based ionic liquids provide good opportunities for the development of ionic liquids in biomedical applications. In this work, the polymerized ionic liquid poly[3‐butyl‐1‐vinylimidazolium L‐proline salt] has been synthesized as a gene vector. The interaction of poly[3‐butyl‐1‐vinylimidazolium L‐proline salt] with DNA was studied by agarose gel electrophoresis. The cell viability was determined through PI (propidium iodine) staining and flow cytometry, showing marginal toxicity toward the cells examined. The transfection efficiency was evaluated through the in vitro transfection experiment. The results indicated that the imidazolium cation had a high binding ability to DNA, and the condensed DNA in the complexes could be effectively protected against enzymatic degradation. Poly[3‐butyl‐1‐vinylimidazolium L‐proline salt] could further transfer the reporter gene into the HeLa cell and successfully mediate the gene expression without the aid of additional agent.
Binding Orientations, QSAR, and Molecular Design of Thiophene Derivative Inhibitors
Authors: Liao Si Yan , Chen Tao Ju , Miao Ti Fang , Qian Li , Zheng Kang Cheng
Published: August 2009

A theoretical study on binding orientations and quantitative structure–activity relationship of thiophene derivatives as inhibitors towards tubulin has been carried out by using the docking analysis and the comparative molecular field analysis. The appropriate binding orientations and conformations of these compounds interacting with tubulin were revealed by docking study; and a 3D‐quantitative structure–activity relationship model showing significant statistical quality and satisfying predictive ability was established, in which the correlation coefficient (R2) and cross‐validation coefficient (q2) are 0.949 and 0.743, respectively. The same model was further applied to predict the pIC50 values for nine congeneric compounds as external test set, and the predictive correlation coefficient reaches 0.929, thus the predictive ability of this 3D‐quantitative structure–activity relationship model can be further confirmed. Some key structural factors of the compounds responsible for cytotoxicity were discussed in detail. Based on these structural factors, three new compounds with higher activity have been designed, and their cytotoxicities were also predicted by the established 3D‐quantitative structure–activity relationship model from comparative molecular field analysis as well as the docking analysis. We hope these theoretical results can be confirmed by experimental work.
Structure Activity Relationship of Antiproliferative Agents using Multiple Linear Regression
Authors: Winfield Leyte L. , Inniss Tasha R. , Smith Dayle M.
Published: August 2009

With cancer‐related fatalities being the second leading cause of death in the USA, understanding the activity of effective chemotherapeutic agents is critical to addressing prostate and other cancers. Celecoxib, an FDA‐approved drug for the treatment of colon tumors, has been used successfully as a lead compound in the development of antiproliferative agents. The ability of celecoxib to inhibit the development and progression of tumors has been connected to a number of mechanisms of actions that are both dependent on and independent of its cyclooxygenase‐2 activity. A structure‐based approach has been employed to develop a model that underscores the structural significance of celecoxib as an antiproliferative agent. By evaluating the structure activity of this library of molecules, we were able to create a QSAR model for predicting the antiproliferative activity of structurally similar molecules. The development of the model will be presented in this paper.
Estimation of the Combined Effect of Eleutherococcus senticosus Extract and Cadmium on Liver Cells
Authors: Smalinskiene Alina , Lesauskaite Vaiva , Zitkevicius Virgilijus , Savickiene Nijole , Savickas Arunas , Ryselis Stanislovas , Sadauskiene Ilona , Ivanov Leonid
Published: August 2009

Cadmium (Cd) is an important industrial pollutant, even though its mechanism of toxicity has not been completely clarified. Cd2+ is toxic to a wide range of organs and tissues. Liver and kidneys are the primary target organs of cadmium toxicity. Cd2+ induces apoptosis and causes necrotic cell death in certain pathophysiological situations. Eleutherococcus senticosus (Rupr. et Maxim.) Maxim. has many beneficial features. It supports the organism's stress response, immune system, and endocrine system, including the adrenal glands, spleen, and thymus gland. The aim of our study was to investigate the effects of the Eleutherococcus senticosus (ES) liquid extract on the accumulation of Cd2+ in liver and on the mitotic and apoptotic activity of liver cells after chronic intoxication by Cd2+. Experiments were carried out on white laboratory mice. Laboratory mice were given to drink solutions of different Cd2+ and ES concentrations for 8 weeks. Cd2+ concentration in mouse liver was detected using atomic absorption spectroscopy. Mitotic and apoptotic activity of liver cells was expressed as an estimated number of mitotic and apoptotic cells in randomly selected reference areas in a histological slide. ES combined with CdCl2 leads to a significant decrease of cadmium concentration in the blood and liver of experimental mice. ES decreased the cadmium‐induced mitotic and apoptotic activity of liver cells.
Plant Polyphenols Effectively Protect HaCaT Cells from Ultraviolet C–Triggered Necrosis and Suppress Inflammatory Chemokine Expression
Authors: Pastore Saveria , Potapovich Alla , Kostyuk Vladimir , Mariani Valentina , Lulli Daniela , De Luca Chiara , Korkina Liudmila
Published: August 2009

Oxidative stress is a common response of epidermal cells to a variety of noxious stimuli such as ultraviolet (UV) radiation from solar light and proinflammatory cytokines from skin‐infiltrating leukocytes. Here, we report that two types of plant‐derived antioxidants, the phenylpropanoid glycoside verbascoside as well as the flavonoids rutin and quercetin possess protective effects against UVC‐induced cell damage and proinflammatory activation. The molecules under investigation were effective against the loss of cell integrity associated with necrosis in doses consistent with their antioxidant activity, whereas they did not significantly oppose UVC‐induced proliferation arrest and apoptosis. By contrast, only verbascoside effectively inhibited cytokine‐induced release of proinflammatory mediators in a dose‐dependent fashion. Verbascoside and its homologue teupolioside dramatically impaired NF‐κB and AP‐1 DNA binding activity. These results suggest that plant polyphenols with antioxidant properties have distinct mechanisms in the suppression of oxidative stress induced in keratinocytes by different stimuli. Verbascoside and teupolioside are hence of potential interest in the protection of the skin from both environmental and inflammatory insults.
Interleukin‐1β–Induced Extracellular Matrix Degradation and Glycosaminoglycan Release Is Inhibited by Curcumin in an Explant Model of Cartilage Inflammation
Authors: Clutterbuck Abigail L. , Mobasheri Ali , Shakibaei Mehdi , Allaway David , Harris Pat
Published: August 2009

Osteoarthritis (OA) is a degenerative and inflammatory disease of synovial joints that is characterized by the loss of articular cartilage, for which there is increasing interest in natural remedies. Curcumin (diferuloylmethane) is the main polyphenol in the spice turmeric, derived from rhizomes of the plantCurcuma longa. Curcumin has potent chemopreventive properties and has been shown to inhibit nuclear factor κB‐mediated inflammatory signaling in many cell types, including chondrocytes. In this study, normal articular cartilage was harvested from metacarpophalangeal and metatarsophalangeal joints of eight horses, euthanized for reasons other than research purposes, to establish an explant model mimicking the inflammatory events that occur in OA. Initially, cartilage explants (N= 8) were stimulated with increasing concentrations of the proinflammatory cytokine IL‐1β to select effective doses for inducing cartilage degeneration in the explant model. Separate cartilage explants were then cotreated with IL‐1β at either 10 ng/mL (n= 3) or 25 ng/mL (n= 3) and curcumin (0.1 μmol/L, 0.5 μmol/L, 1 μmol/L, 10 μmol/L, and 100 μmol/L). After 5 days, the percentage of glycosaminoglycan (GAG) release from the explants was assessed using a dimethylmethylene blue colorimetric assay. Curcumin (100 μmol/L) significantly reduced IL‐1β‐stimulated GAG release in the explants by an average of 20% at 10 ng/mL and 27% at 25 ng/mL back to unstimulated control levels (P< 0.001). Our results suggest that this explant model effectively simulates the proinflammatory cytokine‐mediated release of articular cartilage components seen in OA. Furthermore, the evidence suggests that the inflammatory cartilage explant model is useful for studying the effects of curcumin on inflammatory pathways and gene expression in IL‐1β‐stimulated chondrocytes.
Tumor Necrosis Factor Inhibitors Block Apoptosis of Human Epithelial Cells of the Salivary Glands
Authors: Sisto Margherita , D'Amore Massimo , Caprio Simone , Mitolo Vincenzo , Scagliusi Pasquale , Lisi Sabrina
Published: August 2009

Inhibition of tumor necrosis factor‐α (TNF‐α) in organ‐specific autoimmune disease is proving efficacious for a large number of patients. A wide array of biological agents has been designed to inhibit TNF‐α, such as adalimumab (fully humanized) and etanercept (soluble TNF‐α receptor fusion constructs p75 subunit). Recently, we suggested that anti‐Ro and anti‐La autoantibodies (Abs) isolated from patients with Sjögren's syndrome, an autoimmune rheumatic disease, are able to trigger cell death through extrinsic apoptotic mechanisms in human salivary gland epithelial cells (SGEC). We analyzed if primary human SGEC cultures, established from biopsy of labial minor salivary glands, are able to produce TNF‐α, an inductor of the extrinsic apoptotic pathway, when treated with anti‐Ro autoantibodies. A comparative study was performed to test the efficacy of adalimumab and etanercept to block TNF‐α‐mediated apoptosis. ELISA assay and RT‐PCR were employed to visualize TNF‐α production, and apoptosis was evaluated by DNA ladder and flow cytometry. We found that cell treatment with anti‐Ro autoantibodies determines TNF‐α production that reaches a maximum at 16 h and is decreased (P < 0.05) at 24 and 48 h. Adalimumab seems to be more efficacious than etanercept in blocking TNF‐α‐mediated apoptosis. The YOPRO‐1 (+) and propidium iodide (−) method revealed 60% of apoptotic cells after 24 h of incubation with anti‐Ro compared with 15% of apoptotic cells treated with anti‐Ro plus adalimumab and 25% of apoptotic cells treated with anti‐Ro plus etanercept. The antiapoptotic effect of adalimumab and etanercept was supported by inhibition of DNA laddering induced by anti‐Ro Abs. These data validate the therapeutic efficacy of the anti‐TNF reagents in the treatment of autoimmune disorders.
Induction of Apoptosis and Inhibition of Invasion in Human Hepatoma Cells by Anthocyanins from Meoru
Authors: Shin Dong Yeok , Ryu Chung Ho , Lee Won Sup , Kim Dong Chul , Kim Seok Hyun , Hah Young‐Sool , Lee Sung Joong , Shin Sung Chul , Kang Ho Sung , Choi Yung Hyun
Published: August 2009

Anthocyanins belong to a class of flavonoids exhibiting antioxidant and anti‐inflammatory actions as well as a variety of chemotherapeutic effects. However, little is known about the cellular and molecular mechanism of anticancer activity. In this study, we investigated if the anthocyanins (delphinidin‐3,5‐diglucoside: cyanidin‐3,5‐diglucoside: petunidin‐3,5‐diglucoside: delphinidin‐3‐glucoside: malvdin‐3,5‐diglucoside: peonidin‐3,5‐diglucoside: cyanidin‐3‐glucoside: petunidin‐3‐glucoside: peonidin‐3‐ glucoside: malvidin‐3‐ glucoside = 27: 63: 8.27: 1:2.21: 6.7: 1.25: 5.72: 1.25) isolated from meoru (Vitis coignetiaePulliat) exerted antiproliferative and anti‐invasive and apoptotic effects on human hepatoma Hep3B cells. It was found that the anthocyanins could inhibit cell growth by 75% at the concentration of 400 μg/mL for 48 h. Flow cytometric analysis showed that the anthocyanins increased the amount of DNA fragments (sub‐G1 fraction) in a dose‐dependent manner, which is closely related to mitochondrial dysfunction and reduction in antiapoptotic proteins (Bcl‐2, xIAP, cIAP‐1, and cIAP‐2). The anthocyanins also significantly inhibited the migration and invasion of Hep3B cells through a matrigel‐coated chamber. Taken together this study indicates that the anthocyanins from meoru have antiproliferative and anti‐invasive effects and may induce apoptosis through the activation of the mitochondrial pathway and inhibition of antiapoptotic proteins. This study provides evidence that the anthocyanins isolated from meoru might be useful in the treatment of human hepatitis B‐associated hepatoma.
Erucylphospho‐N,N,N‐trimethylpropylammonium Shows Substantial Cytotoxicity in Multiple Myeloma Cells
Authors: Yosifov Deyan Y. , Konstantinov Spiro M. , Berger Martin R.
Published: August 2009

Multiple myeloma (MM) is a frequent hematological malignancy that is incurable despite recent developments, such as proteasome and angiogenic inhibitors. Erucylphospho‐N,N,N‐trimethylpropylammonium (erufosine) is an i.v. injectable alkylphosphocholine with antineoplastic activity based on an unusual mode of action and is currently undergoing clinical trials in leukemia patients. The aim of this investigation was to evaluate the efficacy of erufosine in MM cells and to study the modulation of cell‐death pathways. The cytotoxicity of erufosine against three MM cell lines (RPMI‐8226, U‐266, and OPM‐2) was determined by the 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide‐dye reduction assay. All MM cell lines responded to erufosine, RPMI‐8226 cells being most and U‐266 being least sensitive. The respective IC50 values were 3.2 and 16.2 μmol/L. Various cell‐death characteristics were studied in response to erufosine, such as morphological changes, oligonucleosomal DNA fragmentation, caspase activation, and poly (ADP)‐ribose polymerase cleavage. Erufosine was found to cause cell shrinkage, chromatin condensation, and caspase‐8 and ‐3 activation. Taken together, our data indicate that erufosine is a potential antimyeloma drug eliciting specific features of apoptotic cell death in vitro.
Effects of Omega‐3 Fatty Acids on Apoptosis of Human Gastric Epithelial Cells Exposed to Silica‐Immobilized Glucose Oxidase
Authors: Yu Ji Hoon , Kang Sin‐Gun , Jung Un‐Young , Jun Chul‐Ho , Kim Hyeyoung
Published: August 2009

Oxidative stress plays a critical role in apoptosis of gastric epithelial cells. Omega‐3 fatty acids show anti‐inflammatory and/or anticancer effects and regulate apoptosis in various cells. In this study, we aimed to investigate whether omega‐3 fatty acids inhibit oxidative stress–induced apoptosis of gastric epithelial cells. The cells received oxidative stress caused by silica‐immobilized glucose oxidase acting on β‐d‐glucose and cultured in the absence or presence of α‐linolenic acid or docosahexanoic acid. Viable cell numbers, levels of H2O2 in the medium, DNA fragmentation, and protein levels of p53 and Bax were determined. As a result, silica‐immobilized glucose oxidase acting on β‐d‐glucose consistently and reproducibly produced H2O2, which decreased cell viability and increased DNA fragmentation of the cells. Omega‐3 fatty acids inhibited oxidative stress–induced cell death, DNA fragmentation, and induction of p53 and Bax of the cells. The silica‐immobilized glucose oxidase could be a useful tool for studies on oxidative stress–induced cellular events because it is reusable and forms a stable enzyme system acting on glucose. Omega‐3 fatty acids may be beneficial for preventing oxidative stress–induced apoptosis by inhibiting apoptotic gene expression and DNA fragmentation of gastric epithelial cells.
A Ketogenic Diet Increases Succinic Dehydrogenase Activity in Aging Cardiomyocytes
Authors: Balietti Marta , Fattoretti Patrizia , Giorgetti Belinda , Casoli Tiziana , Di Stefano Giuseppina , Solazzi Moreno , Platano Daniela , Aicardi Giorgio , Bertoni‐Freddari Carlo
Published: August 2009

Impairment of energy metabolism and an increase of reactive oxygen species (ROS) production seem to play a major role in age‐related apoptotic loss of cardiomyocytes. Succinic dehydrogenase (SDH) is an important marker of the mitochondrial capability to provide an adequate amount of ATP. Moreover, because of its unique redox properties, SDH activity contributes to maintain the reduced state of the ubiquinone pool. Recent reports have shown that ketone body intake improves cardiac metabolic efficiency and exerts a cardioprotective antioxidant action, we therefore performed a cytochemical investigation of SDH activity in cardiomyocytes of late‐adult (19‐month‐old) rats fed for 8 weeks with a medium‐chain triglycerides ketogenic diet (MCT‐KD). Young, age‐matched and old animals fed with a standard chow were used as controls. The overall area of the precipitates (PA) from SDH activity and the area of the SDH‐positive mitochondria (MA) were measured. The percent ratios PA/MA and MA/total myocardial tissue area (MA/TA) were the parameters taken into account. We found that PA/MA was significantly higher in young control rats and in MCT‐KD‐fed rats versus late‐adult and old control rats and in young control versus MCT‐KD‐fed rats. MA/TA of MCT‐KD‐fed rats was significantly higher versus age‐matched and old control rats and tended to be higher versus young control rats; this parameter was significantly higher in young versus old control rats. Thus, MCT‐KD intake partially recovers age‐related decrease of SDH activity and increases the myocardial area occupied by metabolically active mitochondria. These effects might counteract metabolic alterations leading to apoptosis‐induced myocardial atrophy and failure during aging.
Selective Cyclin‐Dependent Kinase Inhibitors Discriminating between Cell Cycle and Transcriptional Kinases
Authors: Węsierska‐Gądek Józefa , Kryštof Vladimír
Published: August 2009

Progression of the cell cycle is controlled by activating and inhibiting cellular factors. The delicate balance between these positive‐ and negative‐acting regulators warrants proper cell cycle progression in normal cells and facilitates cellular response to a variety of stress stimuli. The increased activity of the positive regulators of the cell cycle in cancer cells is frequently accompanied by the loss or inactivation of the inhibitors of cyclin‐dependent kinases (CDKs). The supplementation of the cellular CDK inhibitors by the pharmacological counterparts is a very promising therapeutic option. The generated pharmacological inhibitors of CDKs belong to different classes of compounds and display various CDK inhibitory features. In this article the action and specificity of CDK inhibitor roscovitine, belonging to the group of purine analogues, is reviewed and the rationale for dissecting the inhibitory action on cell cycle and transcriptional CDKs is discussed.
Effects of Carbon Nanotubes on Human Monocytes
Authors: De Nicola Milena , Nuccitelli Silvia , Gattia Daniele Mirabile , Traversa Enrico , Magrini Andrea , Bergamaschi Antonio , Ghibelli Lina
Published: August 2009

Carbon nanotubes are considered to be one of the novel most attractive materials in nanotechnology. Because of their multiple industrial and biomedical applications, thorough studies on their toxicity and biocompatibility become a priority in order to prevent possible health risks. In this study the effects of multiwalled carbon nanotubes (MWCNT) on healthy monocytes from human peripheral blood were investigated. The results indicate that MWCNT exert a cytotoxic effect on monocytes, inducing cell death and increasing the extent of apoptosis induced by a chemotherapic agent. This cytotoxic effect may have important implications, and much attention in terms of evaluation of exposure risks is recommended.
Effect of Epidermal Growth Factor Receptor Inhibitor Alone and in Combination with Cisplatin on Growth of Vulvar Cancer Cells
Authors: Kim Su‐Hyeon , Song Yoo‐Cheol , Kim Su‐Hyeong , Jo Hoenil , Song Yong‐Sang
Published: August 2009

A recent study reported on the efficacy of the EGFR inhibitor on locally advanced vulvar cancer. The aim of this study was to evaluate the effect of an EGFR tyrosine kinase inhibitor (AG1478) alone and in combination with cisplatin on vulvar cancer cells (A431 and SW962). We detected overexpression of EGFR in A431 cells and low expression in SW962 cells. We found that the growth inhibitory effect of AG1478 was dependent upon the expression level of EGFR. The combined treatment of AG1478 with cisplatin failed to exert any synergistic or additive effect in either cell line. In the EGFR signaling pathway, AG1478 decreased the phosphorylation of extracellular signal‐regulated kinase (ERK) and protein kinase B (Akt) in parallel with decreased activity of EGFR in A431 cells, while no changes in ERK and Akt were observed in SW962 cells. The combination of AG1478 with cisplatin completely inhibited the phosphorylation of ERK and Akt in A431 cells but not in SW962 cells. Cisplatin alone and its combination with AG1478 increased the phosphorylation of p38 and c‐Jun N‐terminal kinase (JNK) in both cell lines. In summary, AG1478 inhibited the growth activity of vulvar cancer cells, depending upon the expression level of EGFR, by inhibiting the activities of EGFR, Akt, and ERK. Given the absence of synergistic effects from the combination of AG1478 with cisplatin, combination therapy should be considered cautiously.
Expression of MMP‐2, MMP‐9, and Urokinase‐Type Plasminogen Activator in Cervical Intraepithelial Neoplasia
Authors: No Jae Hong , Jo Hoenil , Kim Su‐Hyeong , Park In‐Ae , Kang Daehee , Lee Chae Hyeong , Han Seung‐Su , Kim Jae Weon , Park Noh‐Hyun , Kang Soon‐Beom , Song Yong‐Sang
Published: August 2009

Matrix metalloproteinase‐2 (MMP‐2), MMP‐9, and urokinase‐type plasminogen activator (uPA) are important factors for cancer invasion and metastasis, degrading the extracellular matrix. They are also associated with angiogenesis. Angiogenic phenotype is another feature of high‐grade cervical intraepithelial neoplasia (CIN). However, their associations with the progression of low‐grade CIN to high‐grade CIN are unexplored. We investigated whether these proteolytic enzyme expressions correlate with the progression of CIN. A total of 39 paraffin‐embedded specimens from 10 patients with CIN grade 1, nine with CIN grade 2, and 20 with CIN grade 3 were assessed immunohistochemically by specific antibodies against MMP‐2, MMP‐9, and uPA. MMP‐9 expression was higher in CIN 3 lesions (47.4%) than in CIN 1 (22.2%) and CIN 2 (20.2%) lesions, although the difference failed to reach statistical significance. The expression level of uPA and MMP‐2 was not associated with the grade of CIN lesions. Interestingly, we found a significant association between expressions of uPA and MMP‐2 (P= 0.028). Our results suggest that MMP‐9 might play a role in the progression of CIN.
Involvement of Both Extrinsic and Intrinsic Apoptotic Pathways in Apoptosis Induced by Genistein in Human Cervical Cancer Cells
Authors: Kim Su‐Hyeon , Kim Su‐Hyeong , Lee Sang‐Chul , Song Yong‐Sang
Published: August 2009

Genistein, a naturally occurring isoflavonoid abundant in soy products, has anticancer activity in multiple tumor cells. In this study, we evaluated the apoptotic effect of genistein on cervical cancer cells and its mechanism of apoptosis. Genistein inhibited the proliferation of cervical cancer cells (HeLa, CaSki, and C33A). HeLa cells were the most sensitive to genistein, whereas CaSki and C33A cells were less sensitive. Sub‐G1 analysis showed that genistein increased apoptotic cells up to 45% at a concentration of 60 μmol/L in HeLa cells, whereas it produced 21% and 17% apoptotic cells in CaSki and C33A cells, respectively, at the same concentration. To determine the apoptotic pathway induced by genistein in the cervical cancer cells, we assessed activation of caspase‐3, ‐8, and ‐9 by immunoblotting. Procaspase‐3, ‐8, and ‐9 were decreased and PARP cleavage increased in a time‐dependent manner after the treatment of genistein in HeLa cells. Also, inhibition of caspase‐3, ‐8, and ‐9 with pharmacological inhibitors reduced genistein‐mediated apoptosis. Interestingly, inhibition of caspase‐8 resulted in remarkable reduction of genistein‐induced apoptosis. Bax expression was increased and total bid decreased, whereas bcl‐2 level was not changed by genistein. Taken together, these results suggest that genistein could induce apoptosis through both extrinsic and intrinsic pathways in human cervical cancer cells.
TRAIL‐Induced Apoptosis
Authors: Corazza Nadia , Kassahn Daniela , Jakob Sabine , Badmann Anastasia , Brunner Thomas
Published: August 2009

The death ligand members of the tumor necrosis factor (TNF) family are potent inducers of apoptosis in a variety of cell types. In particular, TNF‐related apoptosis‐inducing ligand (TRAIL) has recently received much scientific and commercial attention because of its potent tumor cell‐killing activity while leaving normal untransformed cells mostly unaffected. Furthermore, TRAIL strongly synergizes with conventional chemotherapeutic drugs in inducing tumor cell apoptosis, making it a most promising candidate for future cancer therapy. Increasing evidence indicates, however, that TRAIL may also induce or modulate apoptosis in primary cells. A particular concern is the potential side effect of TRAIL‐based tumor therapies in the liver. In this review we summarize some of the recent findings on the role of TRAIL in tumor cell and hepatocyte apoptosis.
Photodynamic Therapy‐Induced Apoptosis of HeLa Cells
Authors: Panzarini Elisa , Tenuzzo Bernardetta , Dini Luciana
Published: August 2009

Photodynamic therapy (PDT), which is a treatment for cancer and certain noncancerous conditions, requires exposure of cells or tissue to a photosensitizing drug followed by irradiation with visible light of the appropriate wavelength. By using Rose Bengal Acetate (RBAc) as the photosensitizer and an innovative green light‐emitting diode, we investigated the efficiency with which apoptosis is induced in HeLa cells, focusing our study on mitochondria alteration and cytochrome c release. Indeed, RBAc is a very efficient fluorogenic substrate and easily enters the cells where the original photoactive molecule is restored by specific esterases. HeLa cells after PDT underwent a consistent rate of apoptosis (peaked at 12 h of recovery post‐PDT). Necrosis was observed at the longest times of recovery as a result of secondary necrosis. PDT gave rise to a series of shape modifications, mainly referable to apoptotic‐related changes (i.e., extensive blebs formation) involving both F‐actin and tubulin networks. Soon after PDT, mitochondria lose their potential membranes and release large quantities of cytochrome c.
Melatonin as a Modulator of Apoptosis in B‐Lymphoma Cells
Authors: Paternoster Laura , Radogna Flavia , Accorsi Augusto , Cristina Albertini Maria , Gualandi Giampiero , Ghibelli Lina
Published: August 2009

Melatonin is considered a promising antitumor agent, promoting apoptosis in tumor cells and contrasting it in normal cells. The basis for this selectivity is presumed to be the ability of melatonin to stimulate reactive oxygen species (ROS) production in tumor cells. Here we investigate the effect of melatonin on three types of human lymphocytes: normal blood lymphocytes, BL41 Burkitt lymphoma, and the cognate Epstein–Barr virus (EBV)‐converted E2r. We found that melatonin promotes ROS production in all these cells. Melatonin protects BL41 from apoptosis in the same manner as normal lymphocytes, whereas E2r are unaffected. These results show that ROS production is not limited to tumor lymphocytes nor it is involved in apoptosis promotion; that melatonin does not promote apoptosis in tumor lymphocytes, but EBV inhibits melatonin anti‐apoptotic effects; and that the anti‐apoptotic effect of melatonin does not depend on the well‐known chemical antioxidant properties of melatonin.
Molecular Response of HL‐60 Cells to Mitotic Inhibitors Vincristine and Taxol Visualized with Apoptosis‐Related Gene Expressions, Including the New Member BCL2L12
Authors: Thomadaki Hellinida , Floros Konstantinos V. , Scorilas Andreas
Published: August 2009

Taxol and vincristine belong to a group of anticancer drugs that target microtubules, subsequently arresting cells at the mitotic phase of the cell cycle and inducing programmed cell death. The BCL2 (bcl‐2) family of genes is of known implication in apoptosis induced by various stimuli, among which BCL2L12, a new member of the family, cloned by our group. For further insights into the mechanisms and molecular targets implicated and modified as a result of apoptosis induced by these two mitosis‐arresting drugs, we studied the possible alterations, at the mRNA level, of various apoptosis‐related genes (BCL2, BAX, BCL2L12, CASPASE‐3, FAS) after leukemia cell (HL‐60) treatment with these drugs. The kinetics of cell toxicity were evaluated by the MTT [3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide] method, trypan blue staining, and cell proliferation efficiency; apoptosis induction was assayed by endonucleosomal cleavage of DNA (DNA laddering); and the expression levels of the genes were analysed by RT‐PCR, using gene‐specific primers. The percentage of nonviable cells was upregulated with increasing cell exposure time and drug concentrations to both taxol and vincristine. Distinct modulations of apoptosis‐related genes at the mRNA level were also observed, mainly concerning BCL2 and BCL2L12 along apoptosis induction. Our results indicate and support the hypothesis that the apoptosis‐related genes BCL2 and BCL2L12 respond similarly to treatment of the human, acute, myelocytic leukemia HL60 cells with the anticancer drugs vincristine and taxol though in a drug‐specific and time‐dependent manner.