bluuebunny/crossref_metadata_2025_split huggingface dataset:
In vitro evaluation of Pandanus amaryllifolius ethanol extract for induction of cell death on non-hormone dependent human breast adenocarcinoma MDA-MB-231 cell via apoptosis
Authors: Chong Hueh Zan , Yeap Swee Keong , Rahmat Asmah , Akim Abdah Md , Alitheen Noorjahan Banu , Othman Fauziah , Gwendoline-Ee Cheng Lian 
Published: August 2012

AbstractBackgroundOur previous study had shown thatP. amaryllifoliuswas able to selectively inhibit cell proliferation of hormone independent breast cancer cell line MDA-MB-231. To understand the mode of killing and mechanism of action forP. amaryllifolius, the ethanol extract was evaluated for their alteration of cell cycle progression, PS externalization, DNA fragmentation and expression of anti/pro-apoptotic related protein.ResultsCell cycle progression analysis, Annexin V and Tunel assays suggested that IC50ofP. amaryllifoliusethanol extract induced G0/G1 cell cycle arrest, PS externalization and DNA fragmentation. On the other hand, ELISA for cytochrome c, caspase-3/7, 8 and 9 indicated that apoptosis was contributed by mitochondrial cytochrome c release via induction of caspase 3/7, 9, and p53 was associated with the suppression of XIAP inP. amaryllifoliustreated MDA-MB-231 cells.ConclusionOur findings suggest thatP. amaryllifoliusethanol extract induced apoptosis on hormone independent breast cancer cell line MDA-MB-231.
Molecular mechanism of cytotoxicity induced by Hsp90-targeted Antp-TPR hybrid peptide in glioblastoma cells
Authors: Horibe Tomohisa , Torisawa Aya , Kohno Masayuki , Kawakami Koji 
Published: August 2012

Abstract

Background
Heat-shock protein 90 (Hsp90) is vital to cell survival under conditions of stress, and binds client proteins to assist in protein stabilization, translocation of polypeptides across cell membranes, and recovery of proteins from aggregates. Therefore, Hsp90 has emerged as an important target for the treatment of cancer. We previously reported that novel Antp-TPR hybrid peptide, which can inhibit the interaction of Hsp90 with the TPR2A domain of Hop, induces selective cytotoxic activity to discriminate between normal and cancer cells both in vitro and in vivo.

Results
In this study, we investigated the functional cancer-cell killing mechanism of Antp-TPR hybrid peptide in glioblastoma (GB) cell lines. It was demonstrated that Antp-TPR peptide induced effective cytotoxic activity in GB cells through the loss of Hsp90 client proteins such as p53, Akt, CDK4, and cRaf. Antp-TPR also did not induce the up-regulation of Hsp70 and Hsp90 proteins, although a small-molecule inhibitor of Hsp90, 17-AAG, induced the up-regulation of these proteins. It was also found that Antp-TPR peptide increased the endoplasmic reticulum unfolded protein response, and the cytotoxic activity of this hybrid peptide to GB cells in the endoplasmic reticulum stress condition.

Conclusion
These results show that targeting of Hsp90 by Antp-TPR could be an attractive approach to selective cancer-cell killing because no other Hsp90-targeted compounds show selective cytotoxic activity. Antp-TPR might provide potent and selective therapeutic options for the treatment of cancer.
Up-regulated oncoprotein P28GANK correlates with proliferation and poor prognosis of human glioma
Authors: Yang Yang , Zhang Chunli , Li Li , Gao Yusong , Luo Xinming , Zhang Yadong , Liu Weiping , Fei Zhou 
Published: August 2012

Abstract

Background
The significance of p28GANK in gliomas remains unknown. This study aims to clarify the clinical significance of p28GANK in human gliomas.

Methods
The expression of p28GANK in 138 gliomas and 50 matched para-cancerous tissues was detected by immunohistochemical staining, and statistical analyses were performed to test the correlation of p28GANK with clinical parameters. To investigate the effects of p28GANK down-regulation on the growth of cells both in vitro and in vivo, an siRNA targeting p28GANK was transfected into U251 cells.

Results
P28GANK expression was significantly higher in tumor specimens than in matched para-cancerous tissues. Over-expressed p28GANK significantly correlated with high karnofsky performance score (KPS), advanced WHO grade and poor overall survival of the patients. Univariate analysis showed that WHO grade and KPS also correlated with the survival of patients, and multivariate analysis suggested that KPS and p28GANK expression were two independent prognostic factors. Moreover, p28GANK gene silencing decreased the malignant growth of U251 cells both in vitro and in vivo.

Conclusions
Increased expression of p28GANK is correlated with poor clinical outcomes in glioma patients. The down-regulation of p28GANK significantly inhibited cell proliferation, indicating that p28GANK might be a potential therapeutic target for glioma treatment.
Computational simulation of the effects of oxygen on the electronic states of hydrogenated 3C-porous SiC
Authors: Trejo Alejandro , Calvino Marbella , Ramos Estrella , Cruz-Irisson Miguel 
Published: August 2012

Abstract
A computational study of the dependence of the electronic band structure and density of states on the chemical surface passivation of cubic porous silicon carbide (pSiC) was performed using ab initio density functional theory and the supercell method. The effects of the porosity and the surface chemistry composition on the energetic stability of pSiC were also investigated. The porous structures were modeled by removing atoms in the [001] direction to produce two different surface chemistries: one fully composed of silicon atoms and one composed of only carbon atoms. The changes in the electronic states of the porous structures as a function of the oxygen (O) content at the surface were studied. Specifically, the oxygen content was increased by replacing pairs of hydrogen (H) atoms on the pore surface with O atoms attached to the surface via either a double bond (X = O) or a bridge bond (X-O-X, X = Si or C). The calculations show that for the fully H-passivated surfaces, the forbidden energy band is larger for the C-rich phase than for the Si-rich phase. For the partially oxygenated Si-rich surfaces, the band gap behavior depends on the O bond type. The energy gap increases as the number of O atoms increases in the supercell if the O atoms are bridge-bonded, whereas the band gap energy does not exhibit a clear trend if O is double-bonded to the surface. In all cases, the gradual oxygenation decreases the band gap of the C-rich surface due to the presence of trap-like states.
A novel Rho-dependent pathway that drives interaction of fascin-1 with p-Lin-11/Isl-1/Mec-3 kinase (LIMK) 1/2 to promote fascin-1/actin binding and filopodia stability
Authors: Jayo Asier , Parsons Maddy , Adams Josephine C 
Published: August 2012

Abstract

Background
Fascin-1 is an actin crosslinking protein that is important for the assembly of cell protrusions in neurons, skeletal and smooth muscle, fibroblasts, and dendritic cells. Although absent from most normal adult epithelia, fascin-1 is upregulated in many human carcinomas, and is associated with poor prognosis because of its promotion of carcinoma cell migration, invasion, and metastasis. Rac and Cdc42 small guanine triphosphatases have been identified as upstream regulators of the association of fascin-1 with actin, but the possible role of Rho has remained obscure. Additionally, experiments have been hampered by the inability to measure the fascin-1/actin interaction directly in intact cells. We investigated the hypothesis that fascin-1 is a functional target of Rho in normal and carcinoma cells, using experimental approaches that included a novel fluorescence resonance energy transfer (FRET)/fluorescence lifetime imaging (FLIM) method to measure the interaction of fascin-1 with actin.

Results
Rho activity modulates the interaction of fascin-1 with actin, as detected by a novel FRET method, in skeletal myoblasts and human colon carcinoma cells. Mechanistically, Rho regulation depends on Rho kinase activity, is independent of the status of myosin II activity, and is not mediated by promotion of the fascin/PKC complex. The p-Lin-11/Isl-1/Mec-3 kinases (LIMK), LIMK1 and LIMK2, act downstream of Rho kinases as novel binding partners of fascin-1, and this complex regulates the stability of filopodia.

Conclusions
We have identified a novel activity of Rho in promoting a complex between fascin-1 and LIMK1/2 that modulates the interaction of fascin-1 with actin. These data provide new mechanistic insight into the intracellular coordination of contractile and protrusive actin-based structures. During the course of the study, we developed a novel FRET method for analysis of the fascin-1/actin interaction, with potential general applicability for analyzing the activities of actin-binding proteins in intact cells.
Neuronal apoptosis by HIV-1 Vpr: contribution of proinflammatory molecular networks from infected target cells
Authors: Guha Debjani , Nagilla Pruthvi , Redinger Carrie , Srinivasan Alagarsamy , Schatten Gerald P , Ayyavoo Velpandi 
Published: August 2012

AbstractBackgroundHuman immunodeficiency virus type 1 (HIV-1) induces neuronal dysfunction through host cellular factors and viral proteins including viral protein R (Vpr) released from infected macrophages/microglia. Vpr is important for infection of terminally differentiated cells such as macrophages. The objective of this study was to assess the effect of Vpr in the context of infectious virus particles on neuronal death through proinflammatory cytokines released from macrophages.MethodsMonocyte-derived macrophages (MDM) were infected with either HIV-1 wild type (HIV-1wt), Vpr deleted mutant (HIV-1∆Vpr) or mock. Cell lysates and culture supernatants from MDMs were analyzed for the expression and release of proinflammatory cytokines by quantitative reverse transcription-PCR and enzyme-linked immunosorbent assay respectively. Mitogen-activated protein kinases (MAPK) were analyzed in activated MDMs by western blots. Further, the effect of Vpr on neuronal apoptosis was examined using primary neurons exposed to culture supernatants from HIV-1wt, HIV-1∆Vpr or mock-infected MDMs by Annexin-V staining, MTT and Caspase - Glo® 3/7 assays. The role of interleukin (IL)-1β, IL-8 and tumor necrosis factor (TNF)-α on neuronal apoptosis was also evaluated in the presence or absence of neutralizing antibodies against these cytokines.ResultsHIV-1∆Vpr-infected MDMs exhibited reduced infection over time and specifically a significant downregulation of IL-1β, IL-8 and TNF-α at the transcriptional and/or protein levels compared to HIV-1wt-infected cultures. This downregulation was due to impaired activation of p38 and stress-activated protein kinase (SAPK)/c-Jun N-terminal kinase (JNK) in HIV-1∆Vpr-infected MDMs. The association of SAPK/JNK and p38 to IL-1β and IL-8 production was confirmed by blocking MAPKs that prevented the elevation of IL-1β and IL-8 in HIV-1wtmore than in HIV-1∆Vpr-infected cultures. Supernatants from HIV-1∆Vpr-infected MDMs containing lower concentrations of IL-1β, IL-8 and TNF-α as well as viral proteins showed a reduced neurotoxicity compared to HIV-1wt-infected MDM supernatants. Reduction of neuronal death in the presence of anti-IL-1β and anti-IL-8 antibodies only in HIV-1wt-infected culture implies that the effect of Vpr on neuronal death is in part mediated through released proinflammatory factors.ConclusionCollectively, these results demonstrate the ability of HIV-1∆Vpr to restrict neuronal apoptosis through dysregulation of multiple proinflammatory cytokines in the infected target cells either directly or indirectly by suppressing viral replication.
Genomic sequencing and analyses of HearMNPV—a new Multinucleocapsid nucleopolyhedrovirus isolated from Helicoverpa armigera
Authors: Tang Ping , Zhang Huan , Li Yinü , Han Bin , Wang Guozeng , Qin Qilian , Zhang Zhifang 
Published: August 2012

Abstract

Background
HearMNPV, a nucleopolyhedrovirus (NPV), which infects the cotton bollworm, Helicoverpa armigera, comprises multiple rod-shaped nucleocapsids in virion(as detected by electron microscopy). HearMNPV shows a different host range compared with H. armigera single-nucleocapsid NPV (HearSNPV). To better understand HearMNPV, the HearMNPV genome was sequenced and analyzed.

Methods
The morphology of HearMNPV was observed by electron microscope. The qPCR was used to determine the replication kinetics of HearMNPV infectious for H. armigera in vivo. A random genomic library of HearMNPV was constructed according to the “partial filling-in” method, the sequence and organization of the HearMNPV genome was analyzed and compared with sequence data from other baculoviruses.

Results
Real time qPCR showed that HearMNPV DNA replication included a decreasing phase, latent phase, exponential phase, and a stationary phase during infection of H. armigera. The HearMNPV genome consists of 154,196 base pairs, with a G + C content of 40.07%. 162 putative ORFs were detected in the HearMNPV genome, which represented 90.16% of the genome. The remaining 9.84% constitute four homologous regions and other non-coding regions. The gene content and gene arrangement in HearMNPV were most similar to those of Mamestra configurata NPV-B (MacoNPV-B), but was different to HearSNPV. Comparison of the genome of HearMNPV and MacoNPV-B suggested that HearMNPV has a deletion of a 5.4-kb fragment containing five ORFs. In addition, HearMNPV orf66, bro genes, and hrs are different to the corresponding parts of the MacoNPV-B genome.

Conclusions
HearMNPV can replicate in vivo in H. armigera and in vitro, and is a new NPV isolate distinguished from HearSNPV. HearMNPV is most closely related to MacoNPV-B, but has a distinct genomic structure, content, and organization.
Synergistic effects of leucine and resveratrol on insulin sensitivity and fat metabolism in adipocytes and mice
Authors: Bruckbauer Antje , Zemel Michael B , Thorpe Teresa , Akula Murthy R , Stuckey Alan C , Osborne Dustin , Martin Emily B , Kennel Stephen , Wall Jonathan S 
Published: August 2012

Abstract

Background
Sirtuins are important regulators of glucose and fat metabolism, and sirtuin activation has been proposed as a therapeutic target for insulin resistance and diabetes. We have shown leucine to increase mitochondrial biogenesis and fat oxidation via Sirt1 dependent pathways. Resveratrol is a widely recognized activator of Sirt; however, the biologically-effective high concentrations used in cell and animal studies are generally impractical or difficult to achieve in humans. Accordingly, we sought to determine whether leucine would exhibit synergy with low levels of resveratrol on sirtuin-dependent outcomes in adipocytes and in diet-induced obese (DIO) mice.

Methods
3T3-L1 mouse adipocytes were treated with Leucine (0.5 mM), β-hydroxy-β-methyl butyrate (HMB) (5 μM) or Resveratrol (200 nM) alone or in combination. In addition, diet-induced obese mice were treated for 6-weeks with low (2 g/kg diet) or high (10 g/kg diet) dose HMB, Leucine (24 g/kg diet; 200% of normal level) or low (12.5 mg/kg diet) or high (225 mg/kg diet) dose resveratrol, alone or as combination with leucine-resveratrol or HMB-resveratrol.

Results
Fatty acid oxidation, AMPK, Sirt1 and Sirt3 activity in 3T3-L1 adipocytes and in muscle cells, were significantly increased by the combinations compared to the individual treatments. Similarly, 6-week feeding of low-dose resveratrol combined with either leucine or its metabolite HMB to DIO mice increased adipose Sirt1 activity, muscle glucose and palmitate uptake (measured via PET/CT), insulin sensitivity (HOMAIR), improved inflammatory stress biomarkers (CRP, IL-6, MCP-1, adiponectin) and reduced adiposity comparable to the effects of high dose resveratrol, while low-dose resveratrol exerted no independent effect.

Conclusion
These data demonstrate that either leucine or its metabolite HMB may be combined with a low concentration of resveratrol to exert synergistic effects on Sirt1-dependent outcomes; this may result in more practical dosing of resveratrol in the management of obesity, insulin-resistance and diabetes.
An analysis of two indigenous reproductive health illnesses in a Nahua community in Veracruz, Mexico
Authors: Smith-Oka Vania 
Published: August 2012

Abstract
Background
This article describes the local concepts indigenous Nahua women hold regarding their reproduction. Specifically it provides a description of two indigenous illnesses—isihuayo and necaxantle, it discusses their etiology, symptoms, and treatments, and it analyzes them within the local ethnomedical framework and sociopolitical context. A perception of female vulnerability is shown to be an underlying shaper of women’s experiences of these illnesses.

Methods
This research took place in a small Nahua village in Mexico. Qualitative data on local perceptions of these illnesses were collected by a combination of participant observation and interviews. Ethnobotanical data was obtained through interviews, and medicinal plants were collected in home gardens, fields, stream banks, and forested areas. The total study population consisted of traditional birth attendants (N = 5), clinicians (N = 8), and laywomen (N = 48).

Results
Results showed that 20% of the village women had suffered from one or both of these illnesses. The article includes a detailed description of the etiology, symptoms, and treatments of these illnesses. Data shows that they were caused by mechanical, physical, and social factors related to a woman’s weakness and/or lack of support. Traditional birth attendants often treated women’s illnesses. Five medicinal plants were salient in the treatment of these illnesses: Ocimum basilicum L., Mentzelia aspera L., Pedilanthus tithymaloides (L.) Poit., and Piper umbellatum L. were used for isihuayo, while Solanum wendlandii Hook f. was used for necaxantle.

Conclusions
The research on these two ethnomedical conditions is a useful case study to understanding how indigenous women experience reproductive health. Reproductive health is not simply about clinically-based medicine but is also about how biomedicine intersects with the local bodily concepts. By describing and analyzing indigenous women’s ill health, one can focus upon the combination of causes—which extend beyond the physical body and into the larger structure that the women exist in.
Pharmacokinetic analysis of topical tobramycin in equine tears by automated immunoassay
Authors: Czerwinski Sarah L , Lyon Andrew W , Skorobohach Brian , Léguillette Renaud 
Published: August 2012

AbstractBackgroundOphthalmic antibiotic therapy in large animals is often used empirically because of the lack of pharmacokinetics studies. The purpose of the study was to determine the pharmacokinetics of topical tobramycin 0.3% ophthalmic solution in the tears of normal horses using an automated immunoassay analysis.ResultsThe mean tobramycin concentrations in the tears at 5, 10, 15, 30 minutes and 1, 2, 4, 6 hours after administration were 759 (±414), 489 (±237), 346 (±227), 147 (±264), 27.6 (±28.4), 14.8 (±66.6), 6.7 (±18.6), and 23.4 (±73.4) mg/L. Mean tobramycin concentration was maintained above the MIC90for commonly isolated bacteria for 68.5 min.ConclusionA single dose of topical tobramycin resulted in therapeutic concentrations of tobramycin in the tears for 1 h after administration. Therapeutic levels of tobramycin remained in equine tears 6 times longer than was reported in rabbit tears.
Specification, annotation, visualization and simulation of a large rule-based model for ERBB receptor signaling
Authors: Creamer Matthew S , Stites Edward C , Aziz Meraj , Cahill James A , Tan Chin Wee , Berens Michael E , Han Haiyong , Bussey Kimberley J , Von Hoff Daniel D , Hlavacek William S , Posner Richard G 
Published: August 2012

Abstract

Background
Mathematical/computational models are needed to understand cell signaling networks, which are complex. Signaling proteins contain multiple functional components and multiple sites of post-translational modification. The multiplicity of components and sites of modification ensures that interactions among signaling proteins have the potential to generate myriad protein complexes and post-translational modification states. As a result, the number of chemical species that can be populated in a cell signaling network, and hence the number of equations in an ordinary differential equation model required to capture the dynamics of these species, is prohibitively large. To overcome this problem, the rule-based modeling approach has been developed for representing interactions within signaling networks efficiently and compactly through coarse-graining of the chemical kinetics of molecular interactions.

Results
Here, we provide a demonstration that the rule-based modeling approach can be used to specify and simulate a large model for ERBB receptor signaling that accounts for site-specific details of protein-protein interactions. The model is considered large because it corresponds to a reaction network containing more reactions than can be practically enumerated. The model encompasses activation of ERK and Akt, and it can be simulated using a network-free simulator, such as NFsim, to generate time courses of phosphorylation for 55 individual serine, threonine, and tyrosine residues. The model is annotated and visualized in the form of an extended contact map.

Conclusions
With the development of software that implements novel computational methods for calculating the dynamics of large-scale rule-based representations of cellular signaling networks, it is now possible to build and analyze models that include a significant fraction of the protein interactions that comprise a signaling network, with incorporation of the site-specific details of the interactions. Modeling at this level of detail is important for understanding cellular signaling.
Processing of DNA double strand breaks by alternative non-homologous end-joining in hyperacetylated chromatin
Authors: Manova Vasilissa , Singh Satyendra K , Iliakis George 
Published: August 2012

Background
Mammalian cells employ at least two subpathways of non-homologous end-joining for the repair of ionizing radiation induced DNA double strand breaks: The canonical DNA-PK-dependent form of non-homologous end-joining (D-NHEJ) and an alternative, slowly operating, error-prone backup pathway (B-NHEJ). In contrast to D-NHEJ, which operates with similar efficiency throughout the cell cycle, B-NHEJ operates more efficiently in G2-phase. Notably, B-NHEJ also shows strong and as of yet unexplained dependency on growth activity and is markedly compromised in serum-deprived cells, or in cells that enter the plateau-phase of growth. The molecular mechanisms underpinning this response remain unknown. Since chromatin structure or changes in chromatin structure are prime candidate-B-NHEJ-modulators, we study here the role of chromatin hyperacetylation, either by HDAC2 knockdown or treatment with the HDAC inhibitor TSA, on the repair by B-NHEJ of IR-induced DSBs.

Results
siRNA-mediated knockdown of HDAC2 fails to provoke histone hyperacetylation in Lig4

-/-
MEFs and has no detectable effect on B-NHEJ function. Treatment with TSA that inhibits multiple HDACs causes efficient, reversible chromatin hyperacetylation in Lig4
-/- MEFs, as well as in human HCT116 Lig4
-/- cells and the human glioma cell line M059K. The IR yield of DSBs in TSA-treated cells remains similar to that of untreated cells despite the expected chromatin relaxation. In addition, chromatin hyperacetylation leaves unchanged repair of DSBs by B-NHEJ in irradiated exponentially growing, or plateau-phase cells. Notably, under the experimental conditions employed here, chromatin hyperacetylation fails to detectably modulate B-NHEJ in M059K cells as well.

Conclusions
In summary, the results show that chromatin acetylation or deacetylation does not affect the kinetics of alternative NHEJ in all types of cells examined both in exponentially growing and serum deprived cultures. We conclude that parameters beyond chromatin acetylation determine B-NHEJ efficiency in the plateau-phase of growth.