bluuebunny/crossref_metadata_2025 huggingface dataset:
Corrosion behavior of twinning‐induced plasticity (TWIP) steel
Authors: Kannan M. Bobby , Raman R. K. Singh , Khoddam S. , Liyanaarachchi S.
Published: December 2011

In this study, the corrosion behavior of twinning‐induced plasticity (TWIP) steel i.e. Fe‐Mn‐Al‐Si steel subjected to cold‐working (0, 20, and 35%), was examined in acidic (0.1 M H2SO4), alkaline (0.1 M NaOH) and chloride‐containing (3.5% NaCl) environments, using potentiodynamic polarization experiments. Interestingly, cold‐working did not show any significant change in the corrosion susceptibility of TWIP steel in all the three environments. However, TWIP steel showed the highest corrosion susceptibility in acidic environment and the lowest in alkaline environment. Scanning electron microscope analysis of the corroded TWIP steel samples revealed high‐localized attack in acidic environment and some pitting corrosion in chloride‐containing solution.
Core‐Shell Structures of Oligosaccharide‐Functionalized Hyperbranched Poly(ethylene imines)
Authors: Thünemann Andreas F. , Bienert Ralf , Appelhans Dietmar , Voit Brigitte
Published: December 2011

Hyperbranched poly(ethylene imine)s (PEIs) functionalized with maltose, maltotriose, and maltoheptaose form distinct core‐shell globular nanoparticles as revealed by small‐angle X‐ray scattering (SAXS). The solution structures are quantified using the Beaucage unified exponential/power‐law approach. SAXS results were confirmed with dynamic light scattering (DLS). We found that all PEI structures are completely insensitive to changes of temperature (5 °C < T < 80 °C) and pH (1 < pH < 10). This remarkable stability of a compact spherical polymeric structure makes the modified PEIs promising for a wide range of biomedical applications.
Benzo[1,2‐b:4,5‐b′]dithiophene Building Block for the Synthesis of Semiconducting Polymers
Authors: Sista Prakash , Biewer Michael C. , Stefan Mihaela C.
Published: December 2011

This review covers the synthesis and polymerization of benzo[1,2‐b: 4,5‐b′]dithiophene (BDT) to generate semiconducting polymers used in organic field‐effect transistors (OFET) and organic solar cells applications.
Turmeric (Curcuma longa) inhibits inflammatory nuclear factor (NF)‐κB and NF‐κB‐regulated gene products and induces death receptors leading to suppressed proliferation, induced chemosensitization, and suppressed osteoclastogenesis
Authors: Kim Ji H. , Gupta Subash C. , Park Byoungduck , Yadav Vivek R. , Aggarwal Bharat B.
Published: December 2011

Scope The incidence of cancer is significantly lower in regions where turmeric is heavily consumed. Whether lower cancer incidence is due to turmeric was investigated by examining its effects on tumor cell proliferation, on pro‐inflammatory transcription factors NF‐κB and STAT3, and on associated gene products

Methods and results Cell proliferation and cell cytotoxicity were measured by the MTT method, NF‐κB activity by EMSA, protein expression by Western blot analysis, ROS generation by FACS analysis, and osteoclastogenesis by TRAP assay. Turmeric inhibited NF‐κB activation and down‐regulated NF‐κB‐regulated gene products linked to survival (Bcl‐2, cFLIP, XIAP, and cIAP1), proliferation (cyclin D1 and c‐Myc), and metastasis (CXCR4) of cancer cells. The spice suppressed the activation of STAT3, and induced the death receptors (DR)4 and DR5. Turmeric enhanced the production of ROS, and suppressed the growth of tumor cell lines. Furthermore, turmeric sensitized the tumor cells to chemotherapeutic agents capecitabine and taxol. Turmeric was found to be more potent than pure curcumin for cell growth inhibition. Turmeric also inhibited NF‐κB activation induced by RANKL that correlated with the suppression of osteoclastogenesis

Conclusion Our results indicate that turmeric can effectively block the proliferation of tumor cells through the suppression of NF‐κB and STAT3 pathways.
Wheat gliadins modified by deamidation are more efficient than native gliadins in inducing a Th2 response in Balb/c mice experimentally sensitized to wheat allergens
Authors: Gourbeyre Pascal , Denery‐Papini Sandra , Larré Colette , Gaudin Jean‐Charles , Brossard Chantal , Bodinier Marie
Published: December 2011

Scope: Wheat gluten proteins such as gliadins constitute major food allergens. Gluten can be modified industrially by deamidation which increases its solubility and enhances its use as a food ingredient. Sensitization to deamidated gluten has been reported to cause severe allergic reactions with anaphylaxis. The aim of this study was therefore to compare the sensitization and elicitation potentials of native (NG) and deamidated (DG) gliadins. The reactivity pattern of mice IgE was also compared with that of DG‐allergic patients.

Methods and results: The ability of DG to sensitize Balb/c mice using intra‐peritoneal administration with aluminium hydroxide as an adjuvant, and to elicit an allergic response after a challenge, was tested in comparison with NG. Mice sensitized with DG secreted higher levels of total IgE, IL‐4, gliadin‐specific IgE and IgG1 than mice sensitized with NG. By contrast, mice sensitized with NG produced higher levels of gliadin‐specific IgG2a and INFγ. After a challenge, histamine levels were higher in mice sensitised with DG.

Conclusions: DG can sensitize mice much more efficiently than NG. Moreover, this mouse model of allergy to DG revealed an IgE reactivity pattern against purified gliadins which was very similar to that of DG‐allergic patients.
Acute effect of whey peptides upon blood pressure of hypertensive rats, and relationship with their angiotensin‐converting enzyme inhibitory activity
Authors: Tavares Tânia , Sevilla María‐Ángeles , Montero María‐José , Carrón Rosalía , Malcata F. Xavier
Published: December 2011

Scope: The aim of this study was to investigate the antihypertensive effect of a peptide fraction (PepC) obtained from a whey protein concentrate following hydrolysis by Cynara cardunculus, as well as of its fraction with MW below 3 kDa (PepCF). Both these concentrates encompassed peptides that exhibited potent in vitro inhibition of angiotensin‐converting enzyme (ACE): two were released from α‐lactalbumin – KGYGGVSLPEW and DKVGINYW, and one from β‐lactoglobulin – DAQSAPLRVY.

Methods and results: Upon oral administration, by gastric intubation, of 400 mg/kg body weight (bw) of those peptide concentrates, or 5 mg/kg bw of the corresponding synthetic peptides, to 12 wk‐old spontaneously hypertensive rats (SHR), the systolic and diastolic blood pressures were monitored by the tail‐cuff method – before, and 2, 4, 6, 8 and 24 h afterwards. Water and zofenopril (5 mg/kg bw) – a known ACE‐inhibitor, were used as negative and positive controls, respectively. Acute administration of PepC, PepCF, KGYGGVSLPEW, DKVGINYW and DAQSAPLRVY caused antihypertensive effects in SHR; the maximum effect occurred by 4 h and 6 h after administration of the peptide concentrates and the synthetic peptides, respectively. PepC and KGYGGVSLPEW also showed ACE‐inhibitory activity in vivo: the pressor effect of angiotensin I was significantly lower, and the response to bradykinin increased when the rats were pre‐treated with either product.

Conclusion: Our results strongly suggest that PepC will be effective as nutraceutical ingredient for the formulation of functional foods aimed at hypertension control.
A preconditioned block Arnoldi method for large Sylvester matrix equations
Authors: Bouhamidi A. , Hached M. , Heyouni M. , Jbilou K.
Published: December 2011

In this paper, we propose a block Arnoldi method for solving the continuous low‐rank Sylvester matrix equation AX + XB = EFT. We consider the case where both A and B are large and sparse real matrices, and E and F are real matrices with small rank. We first apply an alternating directional implicit preconditioner to our equation, turning it into a Stein matrix equation. We then apply a block Krylov method to the Stein equation to extract low‐rank approximate solutions. We give some theoretical results and report numerical experiments to show the efficiency of this method. Copyright © 2011 John Wiley & Sons, Ltd.
A longitudinal study of families with technology‐dependent children
Authors: Toly Valerie Boebel , Musil Carol M. , Carl John C.
Published: December 2011

Few researchers have longitudinally examined families caring for technology‐dependent children at home. We tested a theoretically and empirically based conceptual model by examining family functioning and normalization in 82 mothers (female primary caregivers) twice over 12 months. Time 1 and Time 2 cross‐sectional findings were consistent; the only predictor of family functioning was mothers' depressive symptoms. Contrary to the proposed model, normalization, caregiving duration, and home nursing hours were not directly related to family functioning. Baseline family functioning significantly predicted future family functioning. Also, mothers whose children were no longer technology‐dependent at Time 2 reported significant improvements in family functioning and normalization. An intervention to address high levels of depressive symptoms of these mothers is essential to optimizing family functioning. © 2011 Wiley Periodicals, Inc. Res Nurs Health 35:40–54, 2012
Effect of bilayered stearate ion‐modified MgAl layered double hydroxide on the thermal and mechanical properties of silicone rubber nanocomposites
Authors: Pradhan Bratati , Srivastava Suneel Kumar , Bhowmick Anil Kumar , Saxena Anubhav
Published: December 2011

The homogeneous dispersion of nanofillers in polymer matrices to form polymer nanocomposites remains a challenge in the development of high‐performance polymer materials for various applications. In the work reported, a stearate ion‐modified MgAl layered double hydroxide (St‐LDH) as nanofiller was incorporated in a silicone rubber (SR) matrix by solution intercalation and subsequently characterized. X‐ray diffraction and transmission electron microscopy studies confirm the formation of a predominantly exfoliated dispersion of St‐LDH layers of 75–100 nm in width and about 1–2 nm in thickness in the SR. Thermogravimetric analysis shows that the thermal degradation temperature of the exfoliated SR/St‐LDH (1 wt%) nanocomposites is about 80 °C higher than that of pure SR. Differential scanning calorimetric studies indicate that the melting and crystallization temperatures are higher by 4 and 10 °C for 5 and 8 wt% St‐LDH‐loaded SR nanocomposites compared to neat SR. A significant improvement of 97% in tensile strength and 714% in storage modulus and a reduction of 82% in oxygen permeability have been achieved at 3 wt% St‐LDH loading in SR. Copyright © 2011 Society of Chemical Industry
Skewered reactions in free‐radical crosslinking (co)polymerizations of liquid polybutadiene as internal olefinic multivinyl crosslinker
Authors: Matsumoto Akira , Tani Taisuke , Aota Hiroyuki , Fushihara Kazuhisa , Yamada Mikio
Published: December 2011

As an extension of our continuing studies concerned with the mechanistic discussion of network formation in the free‐radical crosslinking (co)polymerization of multivinyl monomers, this work refers to the skewered reactions in the crosslinking (co)polymerizations of liquid polybutadiene rubber (LBR) as an internal olefinic multivinyl monomer or crosslinker, especially focused on the competitive occurrence of both addition or skewered reaction to internal carbon–carbon (CC) double bonds and abstraction reaction of allylic hydrogens in LBR by growing polymer radical. Thus, LBR is regarded as an internal olefinic multiallyl monomer‐linked allyl groups (CHCHCH2) with methylene units (CH2). First, gelation in the polymerization of LBR was explored in detail, especially at elevated temperatures. The occurrence of intermolecular crosslinking was easier in the order LBR > LBR containing 20 mol % of 1,2‐structural units > liquid polyisoprene rubber. Then, we pursued the polymerization of LBR using dicumyl peroxide (DCPO) as typical organic peroxide used at elevated temperatures. The primary cumyloxy radical generated by the thermal decomposition of DCPO may add to CC double bond or abstract allylic hydrogen or undergo β‐scission to generate a secondary methyl radical. The initiation by the cumyloxy radical was omitted. The ratio of allylic hydrogen abstraction to β‐scission reaction was estimated; thus, only 39% of cumyloxy radical was used for the allylic hydrogen abstraction reaction. The addition of methyl radical to CC double bond was clearly observed. Finally, we pursued the intermolecular and intramolecular skewered reactions in free‐radical crosslinking LBR/vinyl pivalate copolymerizations. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
A series of furan‐aromatic polyesters synthesized via direct esterification method based on renewable resources
Authors: Jiang Min , Liu Qian , Zhang Qiang , Ye Chong , Zhou Guangyuan
Published: December 2011

A series of furan‐aromatic polyesters were successfully synthesized via direct esterification method starting from 2,5‐furandicarboxylic acid, ethylene glycol, 1,3‐propanediol, 1,4‐butanediol, 1,6‐hexanediol, and 1,8‐octanediol and characterized by Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance spectroscopy (1H NMR), X‐ray diffraction (XRD), differential scanning calorimeter (DSC), thermogravimetric analysis (TGA), dynamic mechanical analysis (DMA), tensile tests, and so on. The preliminary evidence clearly showed that direct esterification method was rewarding and worthy to synthesize these furan‐aromatic polyesters. The densities of furan‐aromatic polyesters were ranging from 1.19 to 1.38 kg/m3. The FTIR and 1H NMR confirmed their expected structures in detail. The results of XRD showed that these furan‐aromatic polyesters were crystalline polyesters. The results of DSC, TGA, DMA, and tensile tests showed that they behaved as thermoplastic polyester, had satisfactory thermal and mechanical properties, and their thermal stabilities were quite similar to that of corresponding benzene‐aromatic polyesters. The results of contact angle measurement showed that they were hydrophilic. The properties above showed that furan‐aromatic polyesters based on renewable resources could be a viable alternative to their successful petrochemical benzene‐aromatic counterpart. Furthermore, they could be used as biopolymer materials according their satisfactory thermal and mechanical properties and hydrophilicity in the future. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
‘Open Window’: a randomized trial of the effect of new media art using a virtual window on quality of life in patients' experiencing stem cell transplantation
Authors: McCabe Catherine , Roche Denis , Hegarty Fran , McCann Shaun
Published: December 2011

Objectives

To measure the psychological effect of an art intervention on hospitalized patients and explore benefits to their quality of life.

Methods

We conducted a large prospective randomized trial between July 2006 and August 2009 of an art intervention, Open Window (OW), in patients undergoing stem cell transplantation for a hematological malignancy compared with a control group. The primary endpoint measured the effect of an art intervention on levels of anxiety, depression, and stress using the Hospital Anxiety and Depression Scale and the Distress Thermometer. The secondary endpoint measured the influence of OW on patients' experiences of stem cell transplantation using the OW survey and expectations questionnaires.

Results

Of the 199 patients in the study, 96 were randomized to the intervention group and 103 to the control group. Participants in the intervention group had significantly reduced levels of anxiety on the day before transplant (p = 0.001), at day 7 (p = 0.041), and day 60 (p = 0.035). There was a significant reduction in depression before transplant (p = 0.022). Participants in the intervention group reported better experiences (p < 0.005). Qualitative data showed that those in the intervention group commented freely on their likes and dislikes about OW and how it made them feel.

Conclusion

An art intervention, OW, had a positive influence on health‐related quality of life and patients' experiences of having a stem cell transplant. Copyright © 2011 John Wiley & Sons, Ltd.
Nano Aluminum Energetics: The Effect of Synthesis Method on Morphology and Combustion Performance
Authors: Yarrington Cole D. , Son Steven F. , Foley Timothy J. , Obrey Stephen J. , Pacheco Adam N.
Published: December 2011

Nanoscale aluminum based energetic composites were prepared using polytetrafluoroethylene (PTFE) as an oxidizer, and optimized according to the maximum experimentally observed flame propagation rate in an instrumented burn tube. Optimization of the aluminum‐based composites was performed using nanometric aluminum from two manufacturers, Argonide Corporation and Novacentrix, and the combustion results represent the first direct comparison of these two materials in a burn tube configuration. Argonide aluminum was found to consist of many fused spheres of nano aluminum mixed with some larger micron sized particles. Novacentrix aluminum consisted of spherical particles with a closer particle size distribution. The propagation rate optimized wt.‐% aluminum powder values were 50 and 44.5 for Novacentrix and Argonide, respectively. At the optimized conditions, the time to steady propagation for both Argonide and Novacentrix were similar, however the startup time for the Novacentrix based mixtures was more sensitive to changes in the mixture ratio. The presence of micron sized aluminum and lower surface area, but higher active content in the Argonide mixtures resulted in lower propagation rates, pressurization rates and peak pressures but higher total impulse values. It was found that peak pressure is not the sole determining factor in propagation rate, but the highest pressurization rates correlate with propagation rate.
Comparison of Two Resistance Training Protocols, 6RM versus 12RM, to Increase the 1RM in Healthy Young Adults. A Single‐Blind, Randomized Controlled Trial
Authors: Aarskog Reidar , Wisnes Alexander , Wilhelmsen Kjersti , Skogen Aud , Bjordal Jan Magnus
Published: December 2011

Purpose

The purpose of the study is to compare the effect in healthy young adults of two resistance training protocols, six‐repetition maximum (RM) versus 12RM on maximum strength (1RM).

Method

A single‐blind, randomized controlled trial was used in the study. Sixty‐two healthy physical therapy students, with age (mean [+standard deviation]) 23 (+2.6) years, weight 67.4 (+11.7) kg and height 171.7 (+8.4) cm, of both genders who were recreationally active, but not training systematically, volunteered to participate in the study. They were randomized into two groups (group 1: 24 women and 8 men; group 2: 23 women and 7 men) by a block randomization procedure that ensured equal gender distribution. Sealed envelopes were used to conceal allocation to groups.

Interventions

Group 1 did three sets of 6RM of each exercise, and group 2 did three sets of 12RM. Both groups performed the exercises twice per week for 8 weeks with 3 minutes rest between sets and exercises. Primary outcomes were maximum strength defined as one‐repetition maximum squat (1RMSq) for lower‐body strength and bench press (1RMBp) for upper‐body strength. Secondary outcomes were body weight and Uro Kaleva Kekkonen (UKK) Fitness Index.

Results

Both groups increased strength significantly (p < 0.001) in 1RMSq (6RM 13.6%, 12RM 13.5%) and 1RMBp (6RM 9.2%, 12RM 8.4%). There was no significant difference in the change between the two groups, no change in body weight and only a small increase in UKK Fitness Index.

Conclusion

Both 6RM and 12RM training protocols improve maximum strength in recreationally active healthy young adults, with no significant difference between the protocols. Copyright © 2011 John Wiley & Sons, Ltd.
Protein unfolding and degradation by the AAA+ Lon protease
Authors: Gur Eyal , Vishkautzan Marina , Sauer Robert T.
Published: December 2011

AAA+ proteases employ a hexameric ring that harnesses the energy of ATP binding and hydrolysis to unfold native substrates and translocate the unfolded polypeptide into an interior compartment for degradation. What determines the ability of different AAA+ enzymes to unfold and thus degrade different native protein substrates is currently uncertain. Here, we explore the ability of the E. coli Lon protease to unfold and degrade model protein substrates beginning at N‐terminal, C‐terminal, or internal degrons. Lon has historically been viewed as a weak unfoldase, but we demonstrate robust and processive unfolding/degradation of some substrates with very stable protein domains, including mDHFR and titinI27. For some native substrates, Lon is a more active unfoldase than related AAA+ proteases, including ClpXP and ClpAP. For other substrates, this relationship is reversed. Thus, unfolding activity does not appear to be an intrinsic enzymatic property. Instead, it depends on the specific protease and substrate, suggesting that evolution has diversified rather than optimized the protein unfolding activities of different AAA+ proteases.
Structures of dimethylsulfoniopropionate‐dependent demethylase from the marine organism Pelagabacter ubique
Authors: Schuller David J. , Reisch Chris R. , Moran Mary Ann , Whitman William B. , Lanzilotta William N.
Published: December 2011

Dimethylsulfoniopropionate (DMSP) is a ubiquitous algal metabolite and common carbon and sulfur source for marine bacteria. DMSP is a precursor for the climatically active gas dimethylsulfide that is readily oxidized to sulfate, sulfur dioxide, methanesulfonic acid, and other products that act as cloud condensation nuclei. Although the environmental importance of DMSP metabolism has been known for some time, the enzyme responsible for DMSP demethylation by marine bacterioplankton, dimethylsufoniopropionate‐dependent demethylase A (DmdA, EC 2.1.1.B5), has only recently been identified and biochemically characterized. In this work, we report the structure for the apoenzyme DmdA from Pelagibacter ubique (2.1 Å), as well as for DmdA co‐crystals soaked with substrate DMSP (1.6 Å) or the cofactor tetrahydrofolate (THF) (1.6 Å). Surprisingly, the overall fold of the DmdA is not similar to other enzymes that typically utilize the reduced form of THF and in fact is a triple domain structure similar to what has been observed for the glycine cleavage T protein or sarcosine oxidase. Specifically, while the THF binding fold appears conserved, previous biochemical studies have shown that all enzymes with a similar fold produce 5,10‐methylene‐THF, while DmdA catalyzes a redox‐neutral methyl transfer reaction to produce 5‐methyl‐THF. On the basis of the findings presented herein and the available biochemical data, we outline a mechanism for a redox‐neutral methyl transfer reaction that is novel to this conserved THF binding domain.
Hsp90 inhibitor 17‐AAG inhibits progression of LuCaP35 xenograft prostate tumors to castration resistance
Authors: O'Malley Katherine J. , Langmann Gabrielle , Ai Junkui , Ramos‐Garcia Raquel , Vessella Robert L. , Wang Zhou
Published: December 2011

BACKGROUND

Advanced prostate cancer is currently treated with androgen deprivation therapy (ADT). ADT initially results in tumor regression; however, all patients eventually relapse with castration‐resistant prostate cancer. New approaches to delay the progression of prostate cancer to castration resistance are in desperate need. This study addresses whether targeting Heat shock protein 90 (HSP90) regulation of androgen receptor (AR) can inhibit prostate cancer progression to castration resistance.

METHODS

The HSP90 inhibitor 17‐AAG was injected intraperitoneally into nude mice bearing LuCaP35 xenograft tumors to determine the effect of HSP90 inhibition on prostate cancer progression to castration resistance and host survival.

RESULTS

Administration of 17‐AAG maintained androgen‐sensitivity, delayed the progression of LuCaP35 xenograft tumors to castration resistance, and prolonged the survival of host. In addition, 17‐AAG prevented nuclear localization of endogenous AR in LuCaP35 xenograft tumors in castrated nude mice.

CONCLUSIONS

Targeting Hsp90 or the mechanism by which HSP90 regulates androgen‐independent AR nuclear localization and activation may lead to new approaches to prevent and/or treat castration‐resistant prostate cancer. Prostate 72:1117–1123, 2012. © 2011 Wiley Periodicals, Inc.
The Epigenetic promise for prostate cancer diagnosis
Authors: Van Neste Leander , Herman James G , Otto Gaëtan , Bigley Joseph W , Epstein Jonathan I , Van Criekinge Wim
Published: December 2011

BACKGROUND

Prostate cancer is the most common cancer diagnosis in men and a leading cause of death. Improvements in disease management would have a significant impact and could be facilitated by the development of biomarkers, whether for diagnostic, prognostic, or predictive purposes. The blood‐based prostate biomarker PSA has been part of clinical practice for over two decades, although it is surrounded by controversy. While debates of usefulness are ongoing, alternatives should be explored. Particularly with recent recommendations against routine PSA‐testing, the time is ripe to explore promising biomarkers to yield a more efficient and accurate screening for detection and management of prostate cancer. Epigenetic changes, more specifically DNA methylation, are amongst the most common alterations in human cancer. These changes are associated with transcriptional silencing of genes, leading to an altered cellular biology.

METHODS

One gene in particular, GSTP1, has been widely studied in prostate cancer. Therefore a meta‐analysis has been conducted to examine the role of this and other genes and the potential contribution to prostate cancer management and screening refinement.

RESULTS

More than 30 independent, peer reviewed studies have reported a consistently high sensitivity and specificity of GSTP1 hypermethylation in prostatectomy or biopsy tissue. The meta‐analysis combined and compared these results.

CONCLUSIONS

GSTP1 methylation detection can serve an important role in prostate cancer managment. The meta‐analysis clearly confirmed a link between tissue DNA hypermethylation of this and other genes and prostate cancer. Detection of DNA methylation in genes, including GSTP1, could serve an important role in clinical practice. Prostate 72:1248–1261, 2012. © 2011 Wiley Periodicals, Inc.
MiR‐146a suppresses tumor growth and progression by targeting EGFR pathway and in a p‐ERK‐dependent manner in castration‐resistant prostate cancer
Authors: Xu Bin , Wang Ning , Wang Xuhui , Tong Na , Shao Ning , Tao Jun , Li Pengchao , Niu Xiaobing , Feng Ninghan , Zhang Lihua , Hua Lixin , Wang Zengjun , Chen Ming
Published: December 2011

BACKGROUND

Castration‐resistant prostate cancer (CRPC) is a leading cause of cancer‐related deaths in elder men. This disease has limited therapeutic options and poor prognosis as the underlying molecular mechanisms are not clearly understood. Given the emerging roles of microRNA (miRNA) as a key regulator, we postulated that miRNA may play a significant role in CRPC formation.

METHODS

miR‐146a levels in 15 androgen‐dependent prostate cancer (ADPC) tissues and 5 CRPC tissues were measured by qRT‐PCR. Effects of miR‐146a in cell proliferation and migration in vitro and in vivo were evaluated by MTT assay, colony formation assay, transwell migratory assay, and tumor formation assay, respectively.

RESULTS

we found that miR‐146a expression was significantly decreased in CRPC tissues compared to ADPC tissues. Functional analyses showed that ectopic overexpression of miR‐146a in androgen‐independent cell lines not only inhibited cell growth, colony formation, and migration in vitro, but also reduced tumorigenicity and angiogenesis in vivo. Mechanistic studies revealed that miR‐146a repressed the expression of EGFR through binding to its 3′‐untranslated region. Also, miR‐146a inhibited the expression of MMP2, one of the most important genes in tumor progression. Moreover, downregulation of p‐ERK expression significantly abrogated miR‐146a‐induced prostate cancer cell proliferation.

CONCLUSIONS

Our findings suggest that ubiquitous loss of miR‐146a is a critical mechanism for overexpression of EGFR in CRPC, which is crucial to better understanding the pathogenesis of CRPC. Prostate 72:1171–1178, 2012. © 2011 Wiley Periodicals, Inc.
Association of 5α‐reductase inhibitor use and pathological features of prostate cancer in men undergoing radical prostatectomy
Authors: Hong Sung Kyu , Oh Jong Jin , Lee Sangchul , Lee Hak Min , Byun Seok‐Soo , Choe Gheeyoung , Lee Sang Eun
Published: December 2011

BACKGROUND

We investigated the association of 5α‐reductase inhibitor (5‐ARI) treatment with pathologic and biochemical outcome among the contemporary prostate cancer (PCa) patients undergoing radical prostatectomy.

METHODS

We reviewed records of 1,204 men who underwent radical prostatectomy from 2003 to 2010. We estimated association of 5‐ARI use with high (≥7) pathologic Gleason score and pathologically nonorgan‐confined disease (≥pT3) via logistic regression, and biochemical outcome via Cox proportional hazards regression.

RESULTS

Of 1,204 patients, 50 (4.2%) reported having history 5‐ARI treatment before radical prostatectomy. Median duration of 5‐ARI treatment among the 50 patients was 23.0 months. When adjusted for various factors including age, body mass index, prostate‐specific antigen, clinical stage, biopsy Gleason, and prostate volume, history of 5‐ARI treatment was revealed to be significantly associated with high (≥7) pathologic Gleason score (P = 0.015). Also, 5‐ARI use was observed to significantly associated with higher rates of extraprostatic extension of tumor (P = 0.005) and seminal vesicle invasion (P = 0.003), respectively, when adjusted for same variables. However, 5‐ARI use was not demonstrated to be a significant preoperative predictor of biochemical recurrence‐free survival in multivariate analysis (P = 0.528).

CONCLUSIONS

Our results showed 5‐ARI treatment may be associated with more aggressive PCa demonstrating higher pathologic Gleason score and advanced pathologic tumor stage in men undergoing radical prostatectomy. However, further investigations via larger‐scale, prospective studies would be needed on the actual effect of 5‐ARI treatment on PCa‐specific morbidity and mortality. Prostate 72:1187–1192, 2012. © 2011 Wiley Periodicals, Inc.
Formation of low‐resistance and thermally stable Ohmic contacts to laser lift‐off prepared N‐polar n‐GaN
Authors: Deng Junjing , Chen Zhizhong , Wang Suyuan , Yu Feng , Qi Shengli , Yu Tongjun , Zhang Guoyi
Published: December 2011

In this paper, the electrical charateristics of Ti/Al and (Ga)Ti/Al contacts to N‐polar n‐GaN were investigated. Both as‐deposited and 800 °C‐annealed Ti/Al contacts to N‐polar n‐GaN exhibited Ohmic behavior. However, the as‐deposited Ti/Al Ohmic contacts suffered from electrial degradation even annealed at a low temperature. Based on x‐ray photoemission spectroscopy and Auger electron spectroscopy results, this is attributed to the outdiffusion of Ga. And the introduction of Ga metal at the interface could serve as a diffusion barrier to the outdiffusion of Ga atoms from GaN, which improves the performance of the (Ga)Ti/Al Ohmic contacts to N‐polar GaN and enhances the thermal stability of contacts (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Highly n‐type doped InGaN films for efficient direct solar hydrogen generation
Authors: Mauder C. , Tuna Ö. , Gutrath B. , Balmes V. , Behmenburg H. , Rzheutskii M. V. , Lutsenko E. V. , Yablonskii G. P. , Noyong M. , Simon U. , Heuken M. , Kalisch H. , Vescan A.
Published: December 2011

We report on the metal organic vapour phase epitaxy (MOVPE) and characterization of n‐type InGaN films for application in direct solar water splitting. The 40 nm thick films exhibit an In fraction of 15% and show good structural quality and a surface root mean square (RMS) roughness of only 0.7 nm. An electron concentration of 9 × 1018 cm‐3 at a mobility of 185 cm2/Vs is assessed. The emission peak in photoluminescence (PL) spectra taken at room temperature (RT) is at 2.8 eV, which is consistent to transmission data and the expected bandgap value for this composition. Illumination of the InGaN electrode with a Xe lamp in a 1 M NaOH electrolyte solution at zero external voltage induces a photocurrent (PC) of 0.13 mA/cm2 with a pronounced overshoot in the first few seconds, which we explain by the discharging of a Helmholtz bilayer capacitor. The PC linearly increases with applied voltage while the estimated total conversion efficiency peaks at 0.6 V. Although hydrogen bubbles visibly evolve from the Pt counter electrode, total conversion efficiencies are limited to 0.05%, which is ascribed to incomplete utilization of the optical excitation spectrum and low thickness of both the InGaN film and the space charge region at the semiconductor surface. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Epitaxial lateral overgrowth of InGaN/GaN multiple quantum wells on HVPE GaN template
Authors: Li Xingbin , Yu Tongjun , Tao Yuebin , Deng Junjing , Xu Chenglong , Zhang Guoyi
Published: December 2011

In this study, epitaxial lateral overgrowth (ELOG) on different kinds of patterned hydride vapour phase epitaxy (HVPE) templates was successfully realized by metal organic chemical vapor deposition (MOCVD). InGaN/GaN MQWs were also grown and LED chips were then fabricated. The properties of the wafers and the performance of the LED chips were investigated. The experiment results showed obvious improvement of surface and crystal qualities of the wafers. LED chips also exhibited better luminous properties. Therefore ELOG method is a very effective way to improve crystal quality and oxygen plasma treatment is useful for surface optimization (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Threshold voltage dependence on channel width in nano‐channel array AlGaN/GaN HEMTs
Authors: Liu Shenghou , Cai Yong , Gong Rumin , Wang Jinyan , Zeng Chunhong , Shi Wenhua , Feng Zhihong , Wang Jingjing , Yin Jiayun , Wen Cheng P. , Qin Hua , Zhang Baoshun
Published: December 2011

In this paper, we demonstrate a nano‐channel array (NCA) structure to realize the control of threshold voltage (Vth) of AlGaN/GaN HEMTs. The fabricated NCA structure consists of multiple nano‐channels parallelly connected together. Using this structure, the Vth of AlGaN/GaN HEMTs can be systematically shifted from ‐3.92 V for a conventional depletion‐mode (D‐mode) AlGaN/GaN HEMT to 0.15 V for an enhancement‐mode (E‐mode) AlGaN/GaN HEMT. Besides, an optimum maximum peak transconductance of 235 mS/mm was achieved at the nano‐channel width of 224 nm, which is almost two times larger than that of C‐HEMT (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Surface electronic properties of In‐rich InGaN alloys grown by MOCVD
Authors: Linhart W. M. , Tuna Ö. , Veal T. D. , Mudd J. J. , Giesen C. , Heuken M. , McConville C. F.
Published: December 2011

The band bending, position of Fermi level at the cleaned surfaces and bulk Fermi level of In‐rich InxGa1–xN alloys grown by metal‐organic chemical vapor deposition with a composition of 0.20 ≤ x ≤ 1.00 have been investigated using X‐ray photoemission spectroscopy, infrared reflectivity and Hall effect measurements. Wet etching of InxGa1–xN alloys in HCl successfully reduced the native oxides at the surface, allowing these measurements to be performed more accurately. Electron accumulation layers, accompanied by downward band bending, are present at the surface, with a decrease to flatband conditions occurring at x ≈ 0.2 with increasing Ga fraction. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Estimating incidence rates using exact or interval‐censored data with an application to hospital‐acquired infections
Authors: Deng Lisha , Diggle Peter J. , Cheesbrough John
Published: December 2011

Health‐care providers in the UK and elsewhere are required to maintain records of incidents relating to patient safety, including the date and time of each incident. However, for reporting and analysis, the resulting data are typically grouped into discrete time intervals, for example, weekly or monthly counts. The grouping represents a potential loss of information for estimating variations in incidence over time. We use a Poisson point process model to quantify this loss of information. We also suggest some diagnostic procedures for checking the goodness of fit of the Poisson model. Finally, we apply the model to the data on hospital‐acquired methicillin‐resistantStaphylococcus aureusinfections in two hospitals in the north of England. We find that, in one of the hospitals, the estimated incidence decreased by a factor of approximately 2.3 over a 7‐year period from 0.323 to 0.097 cases per day per 1000 beds, whereas in the other, the estimated incidence showed only a small and nonsignificant decrease over the same period from 0.137 to 0.131. Copyright © 2011 John Wiley & Sons, Ltd.
Some assembly required: How scientific explanations are constructed during clinical interviews
Authors: Sherin Bruce L. , Krakowski Moshe , Lee Victor R.
Published: December 2011

This article is concerned with commonsense science knowledge, the informally gained knowledge of the natural world that students possess prior to formal instruction in a scientific discipline. Although commonsense science has been the focus of substantial study for more than two decades, there are still profound disagreements about its nature and origin, and its role in science learning. What is the reason that it has been so difficult to reach consensus? We believe that the problems run deep; there are difficulties both with how the field has framed questions and the way that it has gone about seeking answers. In order to make progress, we believe it will be helpful to focus on one type of research instrument—the clinical interview—that is employed in the study of commonsense science. More specifically, we argue that we should seek to understand and model, on a moment‐by‐moment basis, student reasoning as it occurs in the interviews employed to study commonsense science. To illustrate and support this claim, we draw on a corpus of interviews with middle school students in which the students were asked questions pertaining to the seasons and climate phenomena. Our analysis of this corpus is based on what we call the mode‐node framework. In this framework, student reasoning is seen as drawing on a set of knowledge elements we call nodes, and this set produces temporary explanatory structures we call dynamic mental constructs. Furthermore, the analysis of our corpus seeks to highlight certain patterns of student reasoning that occur during interviews, patterns in what we call conceptual dynamics. These include patterns in which students can be seen to search through available knowledge (nodes), in which they assemble nodes into an explanation, and in which they converge on and shift among alternative explanations. © 2011 Wiley Periodicals, Inc. J Res Sci Teach 49: 166–198, 2012
Reappraisal of Percutaneous Transhepatic Biliary Drainage Tract Recurrence After Resection of Perihilar Bile Duct Cancer
Authors: Hwang Shin , Song Gi‐Won , Ha Tae‐Yong , Lee Young‐Joo , Kim Ki‐Hun , Ahn Chul‐Soo , Sung Kyu‐Bo , Ko Gi‐Young , Kim Myeong‐Hwan , Lee Sung‐Koo , Moon Deok‐Bog , Jung Dong‐Hwang , Park Gil‐Chun , Lee Sung‐Gyu
Published: December 2011

Background

The high incidence of percutaneous transhepatic biliary drainage (PTBD) tract recurrence after resection of perihilar bile duct cancer (BDC) at a reference single center has suggested the need for endoscopic biliary drainage (EBD) to prevent PTBD‐related tumor recurrence. To determine the general applicability of these findings, we validated the risk of PTBD tract recurrence in patients with resected BDC in our high‐volume center.

Methods

The medical records of 306 patients with perihilar BDC who underwent hepatobiliary resection with curative intent over 10 years were reviewed retrospectively.

Results

Of the 306 patients, 293 (95.8%) underwent biliary decompression, 171 (56.1%) by preoperative PTBD, 62 (20.3%) by EBD alone, and 60 (19.7%) by both. Of the 231 patients who underwent PTBD, 160 (69.3%), 62 (26.8%), and 9 (3.9%) had one, two, or three catheters, respectively (mean of 1.3 catheters per patient for a median 23 days). No patient experienced synchronous PTBD tract metastasis, whereas 4 (1.7%) experienced PTBD tract recurrence a median 13.5 months after surgery, with 3 of these patients having an intraabdominal recurrence soon afterward. Only one patient had a solitary tract recurrence without intraabdominal metastasis. These patients survived for a median 25 months, which is comparable to survival outcomes after noncurative resection. No risk factor was significantly associated with PTBD tract recurrence.

Conclusions

We think that the risk of PTBD tract recurrence after resection of perihilar BDC is not negligible but is much lower than previously reported. There is no definitive reason to avoid PTBD when it is indicated.
Clinical impact of right accessory hepatic artery injury in deceased donor livers
Authors: Ausania Fabio , Al‐Ghnaniem Reyad , Jamieson Neville V. , Praseedom Raaj K.
Published: December 2011

Background

Right accessory hepatic artery (RAHA) injury at retrieval is a rare complication of deceased liver procurement. Arterial reconstruction is often required under these circumstances which could potentially increase the risk of hepatic artery thrombosis (HAT). The aim of this study is to investigate whether RAHA injury affects the incidence of HAT, early biliary complications, or 3‐month graft and patient survival rates.

Methods

All adult liver transplants performed between 1994 and February 2007 at Addenbrooke's Hospital, Cambridge, UK were considered for inclusion in the study. Grafts were divided into three groups depending on the presence of RAHA and injury (Group 1: normal anatomy and single hepatic artery anastomosis; Group 2: RAHA requiring reconstruction; Group 3: RAHA injury requiring reconstruction).

Results

Eight hundred and forty‐four liver transplants were included in the study (Group 1: 654 grafts; Group 2: 63 grafts; Group 3: 14 grafts). The incidence of HAT (Group 1, 2.9%; Group 2, 6.4%; Group 3, 14.3%) was significantly different between the three groups (P = 0.01); biliary complications at 3 months (Group 1, 7.1%; Group 2, 11.1%; Group 3, 7.1%) were not significantly different. Graft and patient survival at 3 months were significantly worse in Group 3 when compared with Group 2 (61.5 vs. 88.3%, P = 0.01; 81.8 vs. 98.2%, P = 0.02).

Conclusion

This is the first study analysing the clinical impact of RAHA injury during liver procurement. We conclude that the use of liver grafts with RAHA injury does result in a higher HAT rate and is also associated with lower graft and patient survival rates at 3 months.
Recombinant Whirly1 translocates from transplastomic chloroplasts to the nucleus
Authors: Isemer Rena , Mulisch Maria , Schäfer Anke , Kirchner Stefan , Koop Hans-Ulrich , Krupinska Karin
Published: December 2011

Whirly1 was shown to be dually located in chloroplasts and nucleus of the same cell. To investigate whether the protein translocates from chloroplasts to the nucleus, we inserted a construct encoding an HA‐tagged Whirly1 into the plastid genome of tobacco. Although the tagged protein was synthesized in plastids, it was detected in nuclei. Dual location of the protein was confirmed by immunocytological analyses. These results indicate that the plastidial Whirly1 is translocated from the plastid to the nucleus where it affects expression of target genes such as PR1. Our results support a role of Whirly1 in plastid‐nucleus communication.
Characterizing the Mechanical Properties of Graphene and Single Walled Carbon Nanotubes
Authors: Tzeng S.-H. , Tsai J.-L.
Published: December 2011

In this study, the mechanical properties of graphene and single walled carbon nanotubes (SWCNTs) were investigated based on molecular dynamics (MD) simulation. During the characterization of the mechanical properties, the atomistic interactions of the carbon atoms were described using the bonded and non-bonded energies. The bonded energy consists of four different interactions: Bond stretching, bond angle bending, dihedral angle torsion, and inversion. On the other hand, the non-bonded interaction between the carbon atoms within the cut-off ranges was regarded as the van der Waals (vdW) force. The effect of vdW force on the mechanical properties of graphene and SWCNTs would be mainly of concern. Simulation results indicated that the Young's modulus of the graphene with vdW force included is 15% higher than that without considering any vdW interaction. The same tendency also was observed in the armchair and zig-zag SWCNTs. Furthermore, it was revealed that the increment of moduli caused by the vdW force could be primarily attributed to the 1-4 vdW interaction. The influence of the vdW interactions on the mechanical properties of graphene and SWCNTs was then elucidated using the parallel spring concept.
Inverse Active Load Inputs Estimation of the 3D Spatial Truss Structure System
Authors: Lee M.-H.
Published: December 2011

This study presents an innovative fuzzy inverse method with the finite-element scheme for estimating the unknown time-varying load inputs on a three-dimensional (3D) spatial truss structural system. The finite-element scheme is employed to discretize the problem in space, allowing multidimensional problems of various geometries to be treated. This method is based on the fuzzy Kalman Filter (FKF) technology and the fuzzy weighting recursive least square method (FWRLSM). The fuzzy Kalman filter measures the system responses at two distinct nodes in the 3D spatial truss structure. The fuzzy weighting recursive least square method is derived using the residual innovation sequence to compute the input loads. The proposed method's superiority is demonstrated using several typical simulation cases that vary with different estimator and the distinct levels of the initial process noise covariance and the measurement noise covariance. The results show that this method has great stability and accuracy.
Study of a Crossflow over a Zero-Net-Mass-Flux Synthetic Jet Driven by a Vibrating Diaphragm
Authors: Tseng L.-Y. , Yang A.-S. , Lin J.-C.
Published: December 2011

Miniature synthetic jet actuators are low operating power, zero-net-mass-flux and very compact devices which have demonstrated their capability in modifying the subsonic flow characteristics for boundary layer flow control. In order to improve the design active flow control systems, the present study aims to examine the formation and interaction of unsteady flowfield of a synthetic jet with external crossflow. In view of a single synthetic jet emitting into a turbulent boundary layer crossflow via a circular orifice, the theoretical model utilized the transient three-dimensional conservation equations of mass and momentum for compressible, turbulent flows with a negligible temperature variation over the computational domain. The motion of a movable membrane plate was also treated as the moving boundary by prescribing the displacement on the plate surface. The predictions by the computational fluid dynamics (CFD) software ACE+®were compared with the measured transient phase-averaged velocities in literature for code validation. The predictions showed the time evolution of the large vortical structure originating from the jet orifice and its successive interaction with the crossflow to change the flow structure inside the boundary layer.