bluuebunny/crossref_metadata_2025 huggingface dataset:
Analgesic‐antitumor peptide inhibits proliferation and migration of SHG‐44 human malignant glioma cells
Authors: Zhao Youlong , Cai Xueting , Ye Tingmei , Huo Jiege , Liu Chao , Zhang Shuangquan , Cao Peng
Published: May 2011

Malignant gliomas, the most common subtype of primary brain tumors, are characterized by high proliferation, great invasion, and neurological destruction and considered to be the deadliest of human cancers. Analgesic‐antitumor peptide (AGAP), one of scorpion toxic polypeptides, has been shown to have antitumor activity. Here, we show that recombinant AGAP (rAGAP) not only inhibits the proliferation of gliomas cell SHG‐44 and rat glioma cell C6, but also suppresses the migration of SHG‐44 cells during wound healing. To explain these phenomena, we find that rAGAP leads to cell cycle of SHG‐44 arrested in G1 phase accompanied by suppressing G1 cell cycle regulatory proteins CDK2, CDK6, and p‐RB by means of the down‐regulated protein expression of p‐AKT. Meanwhile, rAGAP significantly decreases the production of NF‐κB, BCL‐2, p‐p38, p‐c‐Jun, and p‐Erk1/2 and further suppresses the activation of VEGF and MMP‐9 in SHG‐44 cells. These findings suggest rAGAP inhibit proliferation and migration of SHG‐44 cells by arresting cell cycle and interfering p‐AKT, NF‐κB, BCL‐2, and MAPK signaling pathways. J. Cell. Biochem. 112: 2424–2434, 2011. © 2011 Wiley‐Liss, Inc.
Matrix metalloproteinase‐1 induces cleavage of exogenous alphab‐crystallin transduced by a cell‐penetrating peptide
Authors: Yang Seung Won , Lee Seung‐Min , Choi Eun Young , Lee Kyung Hye , Kim Soo Hyuk , Shin Min‐Jeong , Han Ye Sun , Kang Seok‐Min , Chung Ji Hyung
Published: May 2011

Cell‐penetrating peptides (CPPs), including TAT‐CPP, have been used to deliver exogenous proteins into living cells. Although a number of proteins fused to TAT‐CPP can be delivered into various cells, little is known about the proteolytic cleavage of TAT‐fusion proteins in cells. In this study, we demonstrate that a small heat shock protein (sHSP), alphaB‐crystallin (αB‐crystallin), delivered by TAT‐CPP is susceptible to proteolytic cleavage by matrix metalloproteinase‐1 (MMP‐1) in cardiac myoblast H9c2 cells. Recombinant TAT‐αB‐crystallin was efficiently transduced into H9c2 cells. For a few hours following protein transduction, generation of a 14‐kDa fragment, a cleavage band of TAT‐αB‐crystallin, increased in a time‐dependent manner. This fragment was observed only in detergent‐insoluble fractions. Interestingly, treatment with MMP inhibitors blocked the cleavage of TAT‐αB‐crystallin. In test tubes, recombinant MMP‐1 processed TAT‐αB‐crystallin to generate the major cleavage fragment 14‐kDa, as observed in the cells treated with TAT‐αB‐crystallin. The N‐terminal sequences of the 14‐kDa fragment were identified as Leu‐Arg‐Ala‐Pro‐Ser‐Trp‐Phe, indicating that this fragment is generated by cleavage at Phe54‐Leu55 of αB‐crystallin. The MMP‐1‐selective inhibitor abolished the production of 14‐kDa fragments in cells. In addition, the cleaved fragment of TAT‐αB‐crystallin was significantly reduced in cells transfected with MMP‐1 siRNA. Moreover, the enzymatic activity of MMP‐1 was markedly increased in TAT‐αB‐crystallin‐treated cells. TAT‐αB‐crystallin has a cytoprotective effect on H9c2 cells under hypoxic insult, moreover, MMP‐1‐selective inhibitor treatment led to even increased cell viability. These results suggest that MMP‐1 is responsible for proteolytic cleavage of TAT‐αB‐crystallin during its intracellular transduction in H9c2 cells. J. Cell. Biochem. 112: 2454–2462, 2011. © 2011 Wiley‐Liss, Inc.
Evidence that the kinase‐truncated c‐Src regulates NF‐κB signaling by targeting NEMO
Authors: Dai S. , Abu‐Amer W. , Karuppaiah K. , Abu‐Amer Y.
Published: May 2011

The tyrosine kinase c‐Src and transcription factor NF‐κB are considered crucial components required for normal osteoclastogenesis. Genetic ablation of either pathway leads to detrimental osteopetrotic phenotypes in mice. Similarly, obstruction of either pathway halts osteoclastogenesis and lessens various forms of bone loss. It has been shown previously that mice expressing a kinase domain‐truncated c‐Src, termed Src251, develop severe osteopetrosis owing to increased osteoclast apoptosis. It was further suggested that this phenomenon is associated with reduced Akt kinase activity. However, the precise mechanism underlying the osteoclast inhibitory effect of Src251 remains obscure. C‐Src associates with TRAF6‐p62 interacting with receptor activator of NF‐κB (RANK) distal region and the complex facilitate activation of RANK down stream signal transduction cascades including NF‐κB. Given this proximity between c‐Src and NF‐κB signaling in osteoclasts, we surmised that inhibition of osteoclastogenesis by Src251 may be achieved through inhibition of NF‐κB signaling. We have demonstrated recently that NEMO, the regulatory subunit of the IKK complex, is crucial for osteoclastogenesis and interacts with c‐Src in osteoclast progenitors. Transfection studies, in which we employed various forms of c‐Src and NEMO, revealed that the dominant negative form of c‐Src, namely Src251, mediates degradation of NEMO thus halting NF‐κB signaling. Furthermore, degradation of NEMO requires its intact zinc finger domain which is located at the ubiquitination domain. This process also requires appropriate cellular localization of Src251, since deletion of its myristoylation domain ablates its degradation capacity. Buttressing these findings, the expression of NEMO and NF‐κB signaling were significantly reduced in monocytes collected from Src251 transgenic mice. J. Cell. Biochem. 112: 2463–2470, 2011. © 2011 Wiley‐Liss, Inc.
Induction of autophagy by dimethyl cardamonin is associated with proliferative arrest in human colorectal carcinoma HCT116 and LOVO cells
Authors: Ko Hyeonseok , Kim Young‐Joo , Amor Evangeline C. , Lee Jong Wha , Kim Han‐Cheon , Kim Hee Ju , Yang Hyun Ok
Published: May 2011

Dimethyl cardamonin (2′,4′‐dihydroxy‐6′‐methoxy‐3′,5′‐dimethylchalcone; DMC) is a naturally occurring chalcone, and it is the major compound isolated from the leaves of Syzygium samarangense (Blume) Merr. & L.M. Perry (Myrtaceae). Experiments were conducted to determine the effects of DMC on cell proliferation, cell‐cycle distribution, and programmed cell death in cultures of human colorectal carcinoma HCT116 and LOVO cells. Results showed that DMC inhibited HCT116 and LOVO cell proliferation and induced G2/M cell cycle arrest, which was associated with the conversion of microtubule associated protein light chain 3 (LC3)‐I–LC3‐II, an autophagosome marker, and the incorporation of monodansylcadaverine (MDC), a marker for the acidic compartment of autolysosomes or acidic vesicular organelles. The treatment of HCT116 and LOVO cells using a combination of DMC with an autophagy inhibitor, such as 3‐methyladenine (3‐MA), beclin 1 siRNA, or atg5 siRNA, suppressed the effect of DMC‐mediated anti‐proliferation. These results imply that DMC can suppress colorectal carcinoma HCT116 and LOVO cell proliferation through a G2/M phase cell‐cycle delay, and can induce autophagy, the hallmark of Type II programmed cell death (PCD). Taken together, our results suggest that DMC may be an effective chemotherapeutic agent for HCT116 and LOVO colorectal carcinoma cells. J. Cell. Biochem. 112: 2471–2479, 2011. © 2011 Wiley‐Liss, Inc.
The effects of dilution rate and glucose concentration on continuous acetone–butanol–ethanol fermentation by Clostridium acetobutylicum immobilized on bricks
Authors: Yen Hong‐Wei , Li Ruei‐Jei
Published: May 2011

BACKGROUND: Owing to the rapid depletion of petroleum fuel, the production of butanol through biological routes has attracted increasing attention. However, low butanol productivity severely impedes its potential industrial production. It is known that the immobilization of whole cells can enhance productivity in the acetone‐butanol‐ethanol (ABE) continuous fermentation process. Therefore, the objective of this study was to develop a low‐cost continuous operation for butanol production.

RESULTS: Bricks were chosen as cell support because of their low cost and ease of use for immobilization. The solvent productivity for the bricks with immobilized cells was 0.7 g L−1 h−1, 1.89 times that of free cells (0.37 g L−1 h−1) at a dilution rate of 0.054 h−1. The productivity improvement can contribute to greater retention of biomass inside the reactor due to immobilization. The increase in glucose feed concentration raised total solvent production. However, it resulted in a decrease in yield (grams of solvents produced per gram of glucose introduced). Continuous operation with immobilized cells at a dilution rate of 0.107 h−1 resulted in a solvent productivity of 1.21 g L−1 h−1, 2.1 times that of the operation at 0.027 h−1. However, the yield (butanol produced per glucose consumed) was decreased to 0.19 from 0.29 under the same glucose feeding condition of 60 g L−1.

CONCLUSION: The increase in dilution rate and feed glucose concentration enhanced productivity, but decreased the utilization of substrates and the final solvent concentration. Therefore, a balance between productivity and glucose utilization is required to ensure continuous process operation. Copyright © 2011 Society of Chemical Industry
Sonographic appearance of a schwannoma mimicking an axillary lymphadenopathy
Authors: Sohn Yu‐Mee , Kim Sue Yon , Kim Eun‐Kyung
Published: May 2011

Schwannomas are benign nerve sheath tumors derived from Schwann cells and are the most common type of peripheral nerve tumor. Schwannomas occur mainly in the extremities, trunk, and head and are rarely manifested in the axilla. Although various solid tumors can develop in the axilla, only a few cases of schwannoma in the axillary cavity have been reported. Herein, we describe the sonographic appearance of a schwannoma arising from the brachial plexus in the axilla. © 2011 Wiley Periodicals, Inc. J Clin Ultrasound, 2011
First‐trimester septated cystic hygroma and cavum velum interpositum cyst
Authors: Sherer David M. , Dalloul Mudar , Miller Michelle J. , Kheyman Mila , Zinn Harry L. , Abulafia Ovadia
Published: May 2011

First‐trimester septated cystic hygroma, frequently noted during general obstetric first‐trimester screening, is strongly associated with fetal aneuploidy and structural anomalies and is considered an ominous finding. We present the case of a fetus with a first‐trimester septated cystic hygroma and cavum velum interpositum cyst. © 2011 Wiley Periodicals, Inc. J Clin Ultrasound, 2011
Altered oxidative stress profile in the cortex of mice fed an enriched branched‐chain amino acids diet: Possible link with amyotrophic lateral sclerosis?
Authors: Piscopo P. , Crestini A. , Adduci A. , Ferrante A. , Massari M. , Popoli P. , Vanacore N. , Confaloni A.
Published: May 2011

Branched‐chain amino acids (BCAAs), valine, isoleucine, and leucine, are widely used among athletes as dietary integrators. Although the occurrence of untoward effects of BCCA supplementation, with particular regard to neurological disturbances, cannot be excluded, no specific studies have been performed so far. The aim of this work was to evaluate the effects of a diet enriched in BCAAs on the expression of oxidative stress pathway genes in the brain of C57Bl/6J mice. Animals were fed a standard or a BCAA diet for 95 days starting from postnatal day 21 until sacrifice. BCAA treatment, at doses comparable to human usage, significantly down‐regulated the expression of some antioxidant genes, while up‐regulating the expression of some oxygen transporters. In conclusion, it appears that BCAAs administered by diet could alter some specific oxidative stress pathways in the brain. Caution should thus be exercised in the widespread use of BCAAs as dietary integrators in sports practice. © 2011 Wiley‐Liss, Inc.
Tin protoporphyrin provides protection following cerebral hypoxia‐ischemia: Involvement of alternative pathways
Authors: Sutherland Brad A. , Shaw Odette M. , Clarkson Andrew N. , Winburn Ian C. , Errington Adam C. , Dixon Christine L. , Lees George , Sammut Ivan A. , Appleton Ian
Published: May 2011

The contribution of heme oxygenase (HO)‐linked pathways to neurodegeneration following cerebral hypoxia‐ischemia (HI) remains unclear. We investigated whether HO modulators affected HI‐induced brain damage and explored potential mechanisms involved. HI was induced in 26‐day‐old male Wistar rats by left common carotid artery ligation, followed by exposure to a humidified atmosphere of 8% oxygen for 1 hr. Tin protoporphyrin (SnPP; an HO inhibitor), ferriprotoporphyrin (FePP; an HO inducer), or saline was administered intraperitoneally once daily from 1 day prior to HI until sacrifice at 3 days post‐HI. SnPP reduced (P < 0.05) infarct volume compared with saline‐treated animals, but FePP had no effect on brain injury. SnPP did not significantly inhibit HO activity at 3 days post‐HI, but SnPP increased (P < 0.001) total nitric oxide synthase (NOS) activity compared with HI + saline. Both inducible NOS and cyclooxygenase activities were attenuated (P < 0.05) by SnPP, whereas mitochondrial complex I and V activities were augmented (P < 0.05) by SnPP. SnPP had no effect on NMDA receptor currents. Overall, like other HO inhibitors, SnPP produced many nonselective effects, such as attenuation of inflammatory enzymes and increased mitochondrial respiratory function, which were associated with a protective response 3 days post‐HI. © 2011 Wiley‐Liss, Inc.
Reduced gap junctional communication among astrocytes in experimental diabetes: Contributions of altered connexin protein levels and oxidative–nitrosative modifications
Authors: Ball Kelly K. , Harik Lamia , Gandhi Gautam K. , Cruz Nancy F. , Dienel Gerald A.
Published: May 2011

Experimental diabetes increases production of reactive oxygen–nitrogen species and inhibits astrocytic gap junctional communication in tissue culture and brain slices from streptozotocin (STZ)‐diabetic rats by unidentified mechanisms. Relative connexin (Cx) protein levels were assessed by Western blotting using extracts from cultured astrocytes grown in high (25 mmol/liter) or low (5.5 mmol/liter) glucose for 2–3 weeks and STZ‐diabetic rat brain. Chemiluminescent signals for diabetic samples were normalized to those of controls on the same blot and same protein load. Growth in high glucose did not alter relative Cx26 level, whereas Cx30 and glyceraldehyde‐3‐phosphate dehydrogenase (GAPDH) were reduced by ∼30%, and Cx43 increased ∼1.9‐fold. In the inferior colliculus of STZ‐diabetic rats, Cx30 and Cx43 levels in three of four rats were half those of controls, whereas GAPDH and actin were unaffected. Diabetes did not affect levels of Cx30, Cx43, or GAPDH in cerebral cortex, but actin level rose 24%. Cx43 was predominantly phosphorylated in control and diabetic samples, so the reduced dye transfer is not due to overall dephosphorylation of Cx43. Astrocytic growth in high glucose reduced the dye‐labeled area by 75%, but 10 min of treatment with dithiothreitol restored normal dye transfer. In contrast, nitric oxide donors inhibited dye transfer among astrocytes grown in low glucose by 50–65% within 1 hr. Thus, modifications arising from oxidative–nitrosative stress, not altered connexin levels, may underlie the reduced dye transfer among severely hyperglycemic cultured astrocytes, whereas both oxidative–nitrosative stress and regionally selective down‐regulation of connexin protein content may affect gap junctional communication in the brains of STZ‐diabetic rats. © 2011 Wiley‐Liss, Inc.
Overuse of training increases mechanoreceptors in supraspinatus tendon of rats SHR
Authors: de Castro Pochini Alberto , Ejnisman Benno , de Seixas Alves Maria Teresa , Uyeda Luiz Fernando , Nouailhetas Viviane Louise Andree , Han Sang W. , Cohen Moises , Albertoni Walter Manna
Published: May 2011

The presence of mechanoreceptors in tendon after overuse activities can be a further step to learn about tendinopathy and overuse. Studies of tendons mechanoreceptors in rats are rare. We studied 12 isogenic spontaneous hypertensive rats (SHR), which underwent an overuse protocol consisting of an hour per daily session of treadmill running at a speed of 17 m/min, 5 times/week for 4 months. Supraspinatus tendons were evaluated with immunohistochemistry using S100 protein antibodies and histological protocol. Supraspinatus tendons at the end of 4 months of overuse protocol had a high number of media mechanoreceptors (4.3) than controls (0.6). The overexpression of S100 protein antibody in overuse activities maybe could represent a adaptative effort to tendon before the tear. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29:1771–1774, 2011
Ionic interactions and salinity affect monoterpene and phenolic diterpene composition in rosemary (Rosmarinus officinalis)
Authors: Tounekti Taïeb , Vadel Ahmedou Mohammed , Ennajeh Mustapha , Khemira Habib , Munné‐Bosch Sergi
Published: May 2011

In this study, we evaluated how increased cation supply can alleviate the toxic effects of NaCl on plants and how it affects essential oils (EOs) and phenolic diterpene composition in leaves of rosemary (Rosmarinus officinalisL.) plants grown in pots. Two concentrations of the chloride salts KCl, CaCl2, MgCl2, and FeCl3were used together with 100 mM NaCl to study the effects of these nutrients on plant mineral nutrition and leaf monoterpene, phenolic diterpene, and EO composition. The addition of 100 mM NaCl, which decreased K+, Ca2+, and Mg2+concentrations with increasing Na+in leaves, significantly altered secondary metabolite accumulation. Addition of MgCl2and FeCl3altered leaf EO composition in 100 mM NaCl–treated rosemary plants while KCl and CaCl2did not. Furthermore, addition of CaCl2promoted the accumulation of the major phenolic diterpene, carnosic acid, in the leaves. The carnosol concentration was reduced by the addition of KCl to salt‐stressed plants. It is concluded that different salt applications in combination with NaCl treatment may have a pronounced effect on phenolic diterpene and EO composition in rosemary leaves thus indicating that ionic interactions may be carefully considered in the cultivation of these species to achieve the desired concentrations of these secondary metabolites.
Partial dehydration and cryopreservation of Citrus seeds
Authors: Graiver Natalia , Califano Alicia , Zaritzky Noemí
Published: May 2011

BACKGROUND: Three categories of seed storage behavior are generally recognized among plant species: orthodox, intermediate and recalcitrant. Intermediate seeds cannot be stored in liquid nitrogen (LN) without a previous partial dehydration process. The water content (WC) of the seeds at the moment of immersion in LN must be regarded as the most critical factor in cryopreservation. The purpose of this study was to investigate the basis of the optimal hydration status for cryopreservation of Citrus seeds: C. sinensis (sweet orange), C. paradisi (grapefruit), C. reticulata (mandarin) in LN.

RESULTS: To study the tolerance to dehydration and LN exposure, seeds were desiccated by equilibration at relative humidities between 11 and 95%. Sorption isotherms were determined and modeled; lipid content of the seeds was measured. Seed desiccation sensitivity was quantified by the quantal response model. Differential scanning calorimetry (DSC) thermograms were determined on cotyledon tissue at different moisture contents to measure ice melting enthalpies and unfrozen WC. Samples of total seed lipid extract were also analyzed by DSC to identify lipid transitions in the thermograms.

CONCLUSIONS: The limit of hydration for LN Citrus seeds treatment corresponded to the unfrozen WC in the tissue, confirming that seed survival strictly depended on avoidance of intracellular ice formation. Copyright © 2011 Society of Chemical Industry
MDR1 (multidrug resistence 1) can regulate GCS (glucosylceramide synthase) in breast cancer cells
Authors: Zhang Xiaofang , Wu Xiaojuan , Li Juan , Sun Yanlin , Gao Peng , Zhang Cuijuan , Zhang Hui , Zhou Gengyin
Published: May 2011

Background and Objectives

Besides MDR1/P‐glycoprotein (MDR1/P‐gp), glucosylceramide synthase (GCS), an enzyme, which transfers UDP–glucose to ceramide to form glucosylceramide was also related with multidrug resistance (MDR) in breast cancer. Although many research showed that GCS could affect mdr1 in cancer cells, nobody knows that whether mdr1 can affect GCS in breast cancer. Our study aims to verify that.

Methods

A plasmid with multidrug resistence 1(mdr1) cDNA was transfected into the sensitive breast cancer cell line MCF‐7, while an RNA interference (RNAi) vector targeted mdr1 was transfected into the MDR cell line MCF‐7/ADM. Then RT‐PCR, Western blot, MTT, and flow cytometry were used to assess the expression and function of mdr1 and GCS.

Result

The data displayed that up‐regulation of mdr1 could increase the expression of GCS, while the RNAi‐expression plasmids could decrease that. Meantime, the changes of ceramide are opposed to that of GCS and are the same to the alteration of apoptosis rate.

Conclusions

Our results demonstrate that MDR1 could increase cellular apoptosis by regulating the expression of GCS in breast cancer cells. J. Surg. Oncol. 2011; 104:466–471. © 2011 Wiley‐Liss, Inc.
Prognostic significance of distribution of lymph node metastasis in advanced mid or low rectal cancer
Authors: Kim Jin Soo , Sohn Dae Kyung , Park Ji Won , Kim Dae Yong , Chang Hee Jin , Choi Hyo Seong , Oh Jae Hwan
Published: May 2011

Background

Few studies have focused on distribution of lymph node metastasis. The aim of this study is to evaluate the prognostic significance of the location of involved lymph nodes in patients with advanced mid or low rectal cancer.

Methods

We defined proximal lymph node involvement (PLNp) as superior rectal and inferior mesenteric lymph node metastasis along the trunks of the supplying vessel, and mesorectal lymph node involvement (MLNp) as lymph node metastasis located within the mesorectum.

Results

PLNp was identified in 67 patients (8.4%) of total 797 patients. Age <60 years (P = 0.02), poorly differentiated/mucinous histologic type (P = 0.011), and positive perineural invasion (P < 0.001) were risk factors of PLNp in patients with node positive rectal cancer. Patients with PLNp had poorer oncologic outcomes than those without PLNp in terms of overall survival (P < 0.001). For patients with node‐positive rectal cancer, there was significant difference in the overall survival rate between PLNp and MLNp groups, regardless of N stage (P = 0.025 for N1, P = 0.009 for N2).

Conclusions

Our results suggest that PLNp is associated with adverse oncologic outcomes and has prognostic significance in patients with node positive mid or low rectal cancer. J. Surg. Oncol. 2011; 104:486–492. © 2011 Wiley‐Liss, Inc.
Swallowing disturbance questionnaire for detecting dysphagia
Authors: Cohen Jacob T. , Manor Yael
Published: May 2011

Objectives:

To assess the accuracy of the swallowing disturbance questionnaire (SDQ) that had originally been designed and validated for detecting swallowing problems among patients with Parkinson's disease and was now applied for identifying patients with dysphagia associated with various other etiologies.

Study Design:

Prospective.

Methods:

One‐hundred patients with the complaint of swallowing disturbances who underwent a full swallowing survey at the Tel‐Aviv Voice and Swallowing Disorder Clinic participated. They all filled in the SDQ. The collected data included patient characteristics, medical history, and the results of an oromotor examination and a fiberoptic endoscopic evaluation of swallowing (FEES). The SDQ results were compared to the FEES and oromotor examination findings.

Results:

The responses to the questions in the SDQ were highly correlated with the findings of the oral part of the oromotor examination (85.71% sensitivity, 87.6% specificity). Items on the laryngopharyngeal phase reliably assessed dysphagia symptoms in correlation to the FEES examination (67.3% sensitivity, 76.7% specificity). The total SDQ score correlated with the total oromotor and the FEES scores (79.7% sensitivity, 73% specificity).

Conclusions:

The SDQ is a sensitive and accurate tool for identifying patients with true swallowing disturbances arising from different etiologies and for indicating the need for more in‐depth instrumental swallowing evaluations.
Manipulation of terahertz radiation using metamaterials
Authors: Chen H.‐T. , O'Hara J.F. , Azad A.K. , Taylor A.J.
Published: May 2011

During the past decade electromagnetic metamaterials have realized many exotic phenomena that are difficult or impossible using naturally occurring materials. It is their resonantly enhanced interaction with electromagnetic waves that underpins their attractive qualities, which are increasingly important in the terahertz frequency range. Passive and active terahertz metamaterials and devices have enabled novel functionality and unprecedented terahertz device performance. These demonstrations prove their potential to address the so‐called terahertz gap, a technology vacuum associated with the deficiency of natural materials with a desirable terahertz response.
Interactions of fluorinated catalyst and polutetrafluoroethylene in two different plain zinc dialkyldithiophosphate oils and one fully formulated oil using design of experiment
Authors: Nehme Gabi
Published: May 2011

Friction and wear performance of engine oils in the presence of polutetrafluoroethylene (PTFE) and iron fluoride (FeF3) catalyst with plain zinc dialkyldithiophosphate (ZDDP) oils, and fully formulated oils were studied under extreme boundary lubrication (2.72 Hertzian contact load). Two brands of plain ZDDP oils with the same phosphorus percentages were used in the analysis. The study uses design of experiment (DOE) to analyse and optimise the fluorinated oil combinations, thus reducing phosphorus in both plain and fully formulated oils. High and low concentrations of fluorinated catalyst were optimised, and a (PTFE + catalyst) combination suitable for plain ZDDP oil and a fully formulated oil were studied using scanning electron microscopy, energy dispersive spectroscopy, wear profile analysis and tribosurfaces comparison. The experiment indicated that submicron FeF3 catalyst played an important role in preventing the breakdown of the tribofilm.

The reduction of phosphorus in engine oil was examined. Very reproducible boundary lubrication tests with three replicates for each oil blend were conducted as part of the DOE software to study the behaviour of FeF3 catalyst and PTFE or Teflon in developing environmentally friendly (reduced P and S) anti‐wear additives for future engine oil formulations. Several responses with respect to sample failure and post‐wear measurements were analysed, and the overall desirability of the model was targeted to lower phosphorus blends. The goal of the model solution was to check the maximum and minimum interactions of PTFE and selected FeF3 catalyst with respect to both plain ZDDP oils and fully formulated oil. Copyright © 2011 John Wiley & Sons, Ltd.
On the completeness of root vectors of a certain class of differential operators
Authors: Shubov Marianna A.
Published: May 2011

The present paper is the first one in a series of two papers devoted to a unified approach to the problem of completeness of the generalized eigenvectors (the root vectors) for a specific class of linear non‐selfadjoint unbounded differential operators. The list of the problems for which such operators are the dynamics generators includes the following: (a) initial boundary‐value problem (IBVP) for a non‐homogeneous string with both distributed and boundary damping; (b) IBVP for small vibrations of an ideal filament with dissipative boundary condition at one end and with a heavy load at the other end; (c) IBVP for a three‐dimensional damped wave equation with spherically symmetric coefficients and both distributed and boundary damping. In the second paper of the series the following problems will be considered: (a) IBVP for a system of two coupled hyperbolic equations constituting a Timoshenko beam model with variable coefficients and boundary damping; (b) IBVP for a coupled Euler–Bernoulli and Timoshenko beam model with boundary energy dissipation (the model known in engineering literature as bending‐torsion vibration model); (c) IBVP for a system of two Timoshenko beams coupled through linear Van der Waals forces. The model of (c) describes vibrational motion of a double‐walled carbon nanotube. In all of the above cases, the result has been obtained by using Krien’s Theorem on completeness of root vectors of a dissipative operator with a nuclear imaginary part. © 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim
If you feel it now you will think it later: The interactive effects of mood over time on brand extension evaluations
Authors: Sar Sela , Duff Brittany R.L. , Anghelcev George
Published: May 2011

While mood has been found to affect brand extension evaluations, the specific mechanisms by which it affects those evaluations remain largely untested. This study suggests that mood‐induced differences in cognitive processing style (relational vs. item‐specific elaboration) are possible explanations affecting brand extension evaluations. Results of two experiments showed that consumers in a positive (vs. negative) mood engaged in relational (vs. item‐specific) elaboration and consequently evaluated brand extensions and brand extension fit more favorably than consumers in a negative mood. The effects were found immediately after exposure (Experiment 1) and after a one‐week delay (Experiment 2). Theoretical and practical implications are discussed. © 2011 Wiley Periodicals, Inc.
Consumer uncertainty, revisited
Authors: Shiu Edward M.K. , Walsh Gianfranco , Hassan Louise M. , Shaw Deirdre
Published: May 2011

Uncertainty is an important concept within consumer behavior which to date is under‐theorized, especially in relation to important downstream variables such as information search intention and purchase intention, and can therefore lead to a loss of utility. The authors propose a new multidimensional conceptualization of consumer uncertainty and develop a theoretical model of uncertainty within two consumer behavior contexts, namely avoidance of sweatshop apparel and avoidance of food additives. Drawing on literature‐based insights as well as qualitative research and Expected Utility Theory, the authors develop hypotheses that offer insight into the potential antecedents (ambiguity and credibility) and consequences (search intention and purchase intention) of uncertainty. Using survey data, the authors test the hypotheses, finding strong support for many relationships hypothesized. Research and managerial implications are discussed. © 2011 Wiley Periodicals, Inc.
Retail therapy: A strategic effort to improve mood
Authors: Atalay A. Selin , Meloy Margaret G.
Published: May 2011

“Retail therapy” is often applied to the notion of trying to cheer oneself up through the purchase of self‐treats. The negative moods that lead to retail therapy, however, have also been associated with greater impulsivity and a lack of behavioral control. Does this lead to mindless shopping when consumers are “down” and regret later? The current work documents that a bad mood does lead to greater purchase and consumption of unplanned treats for the self. However, it also provides evidence that the consumption of self‐treats can be strategically motivated. Those individuals who do indulge can also exercise restraint if the goal of restraint also leads to improved mood. Finally, retail therapy has lasting positive impacts on mood. Feelings of regret and guilt are not associated with the unplanned purchases made to repair a bad mood. The implications of the research are discussed. © 2011 Wiley Periodicals, Inc.
Neocarzinostatin as a probe for DNA protection activity—molecular interaction with caffeine
Authors: Chin Der‐Hang , Li Huang‐Hsien , Kuo Hsiu‐Maan , Chao Pei‐Dawn Lee , Liu Chia‐Wen
Published: May 2011

Neocarzinostatin (NCS), a potent mutagen and carcinogen, consists of an enediyne prodrug and a protein carrier. It has a unique double role in that it intercalates into DNA and imposes radical‐mediated damage after thiol activation. Here we employed NCS as a probe to examine the DNA‐protection capability of caffeine, one of common dietary phytochemicals with potential cancer‐chemopreventive activity. NCS at the nanomolar concentration range could induce significant single‐ and double‐strand lesions in DNA, but up to 75 ± 5% of such lesions were found to be efficiently inhibited by caffeine. The percentage of inhibition was caffeine‐concentration dependent, but was not sensitive to the DNA‐lesion types. The well‐characterized activation reactions of NCS allowed us to explore the effect of caffeine on the enediyne‐generated radicals. Postactivation analyses by chromatographic and mass spectroscopic methods identified a caffeine‐quenched enediyne‐radical adduct, but the yield was too small to fully account for the large inhibition effect on DNA lesions. The affinity between NCS chromophore and DNA was characterized by a fluorescence‐based kinetic method. The drug–DNA intercalation was hampered by caffeine, and the caffeine‐induced increases in DNA–drug dissociation constant was caffeine‐concentration dependent, suggesting importance of binding affinity in the protection mechanism. Caffeine has been shown to be both an effective free radical scavenger and an intercalation inhibitor. Our results demonstrated that caffeine ingeniously protected DNA against the enediyne‐induced damages mainly by inhibiting DNA intercalation beforehand. The direct scavenging of the DNA‐bound NCS free radicals by caffeine played only a minor role. Mol. Carcinog. © 2011 Wiley Periodicals, Inc.
Focal adhesion kinase is required for KSHV vGPCR signaling
Authors: He Meilan , Bakken Thomas , Kassimova Alia , Boshoff Chris , Philpott Nicola , Cannon Mark L.
Published: May 2011

Kaposi's sarcoma‐associated herpesvirus (KSHV) is the etiologic agent of Kaposi's sarcoma, an angiogenic and inflammatory endothelial cell (EC) tumor that is common in areas of high KSHV prevalence. KSHV encodes a pro‐angiogenic viral chemokine receptor (vGPCR) that promotes EC growth in vitro and KS‐like tumors in mouse models. vGPCR is therefore considered a viral oncogene that plays a crucial role in the pathobiology of KS. In this study, we show that focal adhesion kinase (FAK) becomes activated upon vGPCR expression in primary ECs and that FAK is required for vGPCR‐mediated activation of ERK1/2, NFκB, AP‐1, and vGPCR‐induced migration and inhibition of anoikis. FAK is crucial to cell motility and tumor invasiveness and is a potential therapeutic target in various malignancies. Our data show that via vGPCR, KSHV has evolved a way to constitutively activate FAK signaling. Mol. Carcinog. © 2011 Wiley Periodicals, Inc.
Synergism between resveratrol and other phytochemicals: Implications for obesity and osteoporosis
Authors: Rayalam Srujana , Della‐Fera Mary Anne , Baile Clifton A.
Published: May 2011

Resveratrol, a phytoalexin, has gained much attention recently due to its effects on sirtuins. While the anti‐cancer properties of resveratrol have been extensively investigated, the anti‐adipogenic and osteogenic effects of resveratrol are also gaining considerable interest. The finding that resveratrol supplementation mimics caloric restriction prompted researchers to study the effects of resveratrol on lipid metabolism. Mesenchymal stem cells are the precursors for both adipocytes and osteoblasts. In the aging population, differentiation to adipocytes dominates over the differentiation to osteoblasts in bone marrow, contributing to the increased tendency for fractures to occur in the elderly. Thus, an inverse relationship exists between adipocytes and osteoblasts in the bone marrow. Resveratrol acts on several molecular targets in adipocytes and osteoblasts leading to a decrease in adipocyte number and size and an increase in osteogenesis. Furthermore, resveratrol in combination with genistein and quercetin synergistically decreased adipogenesis in murine and human adipocytes. A recent in vivo study showed that phytochemicals including resveratrol in combination with vitamin D prevented weight gain and bone loss in a postmenopausal rat model. Therefore, combinations of resveratrol with other phytochemicals may lead to potential novel potent therapies for both obesity and osteoporosis.
Cancer chemoprevention with green tea catechins by targeting receptor tyrosine kinases
Authors: Shimizu Masahito , Adachi Seiji , Masuda Muneyuki , Kozawa Osamu , Moriwaki Hisataka
Published: May 2011

Recent studies indicate that receptor tyrosine kinases (RTKs), which play important roles in cell proliferation, are one of the possible targets of green tea catechins (GTCs) in cancer cell growth inhibition. (−)‐Epigallocatechin‐3‐gallate (EGCG), the major catechin in green tea, inhibits cell proliferation and induces apoptosis in various types of cancer cells, including colorectal cancer and hepatocellular carcinoma cells, by blocking the activation of the epidermal growth factor receptor (EGFR) family of RTKs. EGCG inhibits the activation of insulin‐like growth factor‐1 receptor (IGF‐1R) and VEGFR2, the other members of the RTK family, and this effect is also associated with the anticancer and chemopreventive properties of this agent. EGCG suppresses the activation of EGFR in part by altering membrane lipid organization and causing the subsequent inhibition of the dimerization and activation of this receptor. Preliminary trials have shown that GTCs successfully prevent the development and progression of precancerous lesions, such as colorectal adenomas, without causing severe adverse effects. The present report reviews evidence indicating that GTCs exert anticancer and chemopreventive effects by inhibiting the activation of specific RTKs, especially EGFR, IGF‐1R, and VEGFR2, and concludes that targeting RTKs and their related signaling pathways by using tea catechins could be a promising strategy for the prevention of human cancers.
The role of antioxidant versus pro‐oxidant effects of green tea polyphenols in cancer prevention
Authors: Forester Sarah C. , Lambert Joshua D.
Published: May 2011

Consumption of green tea (Camellia sinensis) may provide protection against chronic diseases, including cancer. Green tea polyphenols are believed to be responsible for this cancer preventive effect, and the antioxidant activity of the green tea polyphenols has been implicated as a potential mechanism. This hypothesis has been difficult to study in vivo due to metabolism of these compounds and poor understanding of the redox environment in vivo. Green tea polyphenols can be direct antioxidants by scavenging reactive oxygen species or chelating transition metals as has been demonstrated in vitro. Alternatively, they may act indirectly by upregulating phase II antioxidant enzymes. Evidence of this latter effect has been observed in vivo, yet more work is required to determine under which conditions these mechanisms occur. Green tea polyphenols can also be potent pro‐oxidants, both in vitro and in vivo, leading to the formation of hydrogen peroxide, the hydroxyl radical, and superoxide anion. The potential role of these pro‐oxidant effects in the cancer preventive activity of green tea is not well understood. The evidence for not only the antioxidant, but also pro‐oxidant, properties of green tea is discussed in the present review.
Curcumin reduces pulmonary tumorigenesis in vascular endothelial growth factor (VEGF)‐overexpressing transgenic mice
Authors: Tung Yu‐Tang , Chen Hsiao‐Ling , Lai Cheng‐Wei , Shen Chih‐Jie , Lai Yi‐Wen , Chen Chuan‐Mu
Published: May 2011

Scope: We investigated the inhibition of pulmonary tumor formation through treatment with curcumin in transgenic mice.

Methods and results: In this study, a strain of transgenic mice carrying human vascular endothelial growth factor A165 (hVEGF‐A165) gene to induce pulmonary tumor was used as an in vivo cancer therapy model. We found that curcumin significantly reduced hVEGF‐A165 overexpression to normal, specifically in Clara cells of the lungs of transgenic mice, and suppressed the formation of tumors. In addition, we demonstrated a relationship between curcumin treatment and the expression of VEGF, EGFR, ERK2, and Cyclin A at the transcriptional and translational levels. We also noticed a reduction of Cyclin A and Cyclin B after curcumin treatment that had an effect on the cell cycle. Curcumin‐induced inhibition of Cyclin A and Cyclin B likely results in decreased progression through S and G2/M phases. These results demonstrated that the expression of proteins involved in the S to M phase transition in transgenic mice is suppressed by curcumin.

Conclusion: A Data suggest that a blockade of the cell cycle may be a critical mechanism for the observed effects on vasculogenesis and angiogenesis following treatment with curcumin.
Hypocholesterolemic and hypoglycemic effects of enzymatically modified carbohydrates from rice in high‐fat‐fed C57BL/6J mice
Authors: Bhuiyan Muhammad J. H. , Do Ha Viet , Mun Saehun , Jun Hee‐jin , Lee Ji Hae , Kim Yong‐Ro , Lee Sung‐Joon
Published: May 2011

Scope: Enzymatically modified rice starch (ERS) synthesized with 4‐α‐glucanotransferase has a longer structure than rice starch, which could delay digestion, similar to dietary fiber. We investigated the effects of ERS on glucose and lipid metabolism with mice fed a high‐fat diet containing ERS (HFD‐ERS).

Method and results: Four weeks of ERS feeding showed hypoglycemic effects with a significant reduction in fasting glucose (46%), insulin (57%), and leptin (83%) levels; improved glucose tolerance (20% in AUC of oral glucose tolerance test); and increased adiponectin concentrations (+27%) compared to the HFD group. Notably, phosphorylation of AMP kinase (AMPK) was markedly induced in the HFD‐ERS livers compared to HFD livers. Additionally, ERS significantly reduced total cholesterol concentrations with induction of fecal bile acid excretion (+21%, P<0.05) in the HFD‐ERS group compared to the HFD group. The mRNA and protein expressions of hepatic LDL receptors were significantly induced. However, cholesterol 7 alpha‐hydroxylase (CYP7A1) expression was downregulated possibly due to induction of intestinal farnesoid X receptor (FXR; +2.4‐fold, p<0.05) and fibroblast growth factor‐15 (FGF‐15; +2.2‐fold, p<0.01).

Conclusion: Our data suggest that ERS feeding may have hypoglycemic and hypocholesterolemic effects via a mechanism similar to that of dietary fiber.
Master of Science und Diplôme d'Ingénieur
Authors: Breternitz Joachim
Published: May 2011

Chemiestudenten der Technischen Universität Dresden können einen Teil ihres Studiums an einer der TU‐Partnerhochschulen in Frankreich absolvieren und erwerben neben dem deutschen einen französischen Abschluss. Joachim Breternitz macht mit und hat sich für Rennes entschieden.
Urinary incontinence: An under‐recognized risk factor for falls among elderly dementia patients
Authors: Lee Chun‐Ying , Chen Liang‐Kung , Lo Yuk‐Keung , Liang Chih‐Kuang , Chou Ming‐Yueh , Lo Chung‐Cheng , Huang Chia‐Tsuan , Lin Yu‐Te
Published: May 2011

Aims

Elderly people with dementia are at increased risk of falls and intervention trials to prevent falls have failed to demonstrate clinical effectiveness in this population. This study evaluates the role of urinary incontinence as a fall risk factor in older patients with dementia, with the aim of developing relevant intervention strategies.

Methods

Elderly patients with dementia visiting our center were recruited. All subjects underwent a Comprehensive Geriatric Assessment (CGA), and patients were divided into two groups (fall and non‐fall) according to their history of falls in the past year. Components of the CGA, including physical function, mental function, depressive symptoms, incontinence, and nutritional status, were evaluated according to fall history.

Results

Overall, 159 patients with dementia (mean age 77.3 ± 9.0 years, 59.1% male) participated. Fifty‐four patients (34.0%) had experienced falls in the past year. Among all subjects, 50.3% were diagnosed with mild dementia, 37.7% with moderate dementia, and 12.0% with severe dementia according to an established Clinical Dementia Rating scale. Subjects in the fall group displayed poorer physical function, balance, depressive mood, nutritional status, urinary incontinence, and had an increased prevalence of polypharmacy. However, multivariate analysis revealed urinary incontinence as the only independent risk factor for falls (OR = 4.9 ± 2.2, 95% CI: 2.0–12.0, P < 0.001).

Conclusions

Urinary incontinence is a previously unidentified risk factor for falls among elderly dementia patients. An interventional study with the focus of urinary incontinence could improve the effectiveness of fall prevention among these patients. Neurourol. Urodynam. 30:1286–1290, 2011. © 2011 Wiley‐Liss, Inc.
Synthesis and characterization of phthalazinone‐based poly(aryl ether ketone) derived from 4,4′‐dichlorobenzophenone
Authors: Zhou Hongxin , Liu Cheng , Wang Jinyan , Jian Xigao
Published: May 2011

As distinguished from the conventional preparation of poly(aryl ether ketone)s utilizing 4,4′‐difluorobenzophenone, a novel synthetic method of high molecular weight poly(phthalazinone ether ketone) derived from 4,4′‐dichlorobenzophenone was studied. Reaction conditions to get high molecular weight polymer were investigated in details. Experimentally, sulfolane was chosen as the reaction media and high molecular weight polymer could be obtained in 7–8 hr at 210°C. The cyclic oligomers in the polymer product reduced to below 3.0% when the concentration of the reactant is 1.6–1.7 g/ml. Fourier transform infrared (FT‐IR), 1H NMR, and elemental analysis were used to confirm the structure of the obtained polymer. The amorphous polymer showed reasonable solubility in selective solvent, such as chloroform and N‐methyl‐2‐pyrrolidone, and tough, flexible, and transparent thin film can be readily prepared from their N‐methyl‐2‐pyrrolidone solution. The obtained polymer showed high glass transition temperature (Tg) up to 261°C detected by differential scanning calorimetry (DSC), and the temperature of 5% weight loss under nitrogen higher than 500°C detected by thermal gravimetric analysis (TGA), indicating its excellent thermal stability. Copyright © 2011 John Wiley & Sons, Ltd.
Phase structure and mechanical properties of modified poly(phenylene oxide) with high fluidity
Authors: Li Jian‐Xiong , Chan Chi‐Ming
Published: May 2011

Polyphenylene oxide (PPO) possesses excellent mechanical properties and heat resistance but extremely high viscosity. Virgin PPO has to be blended with polystyrene (PS) to reduce the viscosity. However, PS is miscible with PPO; it reduces not only the viscosity but also the heat distortion temperature and, consequently, narrows the applications. This paper is an attempt to develop crystalline additives that will dissolve in PPO at processing temperature but precipitate and recrystallize after molding. Thereby, the additives are able to reduce the viscosity of PPO melts but will not reduce the heat distortion temperature of PPO materials. In the present work, a PPO was compounded with bisphenol‐A and bisphenol‐S as well as PS separately on Haake Rheometer and the mixing torque was recorded. The dynamic properties of the modified PPO were analyzed with DMA and the mechanical properties were tested at ambient and elevated temperatures. The phase structures were examined with DSC and TEM. The effect of the additives on the fluidity, mechanical properties, and heat distortion temperature of the PPO compounds was investigated. All three additives dissolved in the PPO during mixing and reduced the mixing torque. But bisphenol‐S precipitated after molding and is present as 40 nm crystalline phases in the molded materials; it did not affect the glass transition nor did it deteriorate the performance at elevated temperature. While bisphenol‐A did not recrystallize after molding; it reduced the Tg and heat distortion temperature as does PS. General principles about such plasticizers with phase transition for PPO were proposed. Copyright © 2011 John Wiley & Sons, Ltd.