bluuebunny/crossref_metadata_2025_split huggingface dataset:
Perinatal dexamethasone‐induced alterations in apoptosis within the hippocampus and paraventricular nucleus of the hypothalamus are influenced by age and sex
Authors: Zuloaga Damian G. , Carbone David L. , Quihuis Alicia , Hiroi Ryoko , Chong David L. , Handa Robert J. 
Published: March 2012

AbstractExposure to high levels of glucocorticoids (GCs) during development leads to long‐term changes in hypothalamic‐pituitary‐adrenal (HPA) axis regulation, although little is known about the neural mechanisms that underlie these alterations. In this study, we investigated the effects of late gestational (days 18–22) or postnatal (days 4–6) administration of the GC receptor agonist dexamethasone (DEX) on an apoptosis marker in two brain regions critical to HPA axis regulation, the hippocampus and the hypothalamic paraventricular nucleus (PVN). One day after the final DEX injection, male and female rats were sacrificed, and brains were processed for immunohistochemical detection of cleaved caspase‐3, an apoptotic cell death indicator. DEX increased cleaved caspase‐3 immunoreactivity in the CA1 hippocampal region of both sexes following prenatal but not postnatal treatment. Prenatal DEX also increased caspase‐3 immunoreactivity in the CA3 region, an elevation that tended to be greater in females. In contrast, postnatal DEX resulted in a much smaller, albeit significant, induction in CA3 caspase‐3 compared with prenatal treatment. Quantitative real‐time PCR analysis revealed that prenatal but not postnatal DEX‐induced hippocampal cleaved caspase‐3 correlated with elevated mRNA of the proapoptotic gene Bad. Few caspase‐3‐ir cells were identified within the PVN regardless of treatment age, although postnatal but not prenatal DEX increased this number. However, the region immediately surrounding the PVN (peri‐PVN) showed significant increases in caspase‐3‐ir cells following pre‐ and postnatal DEX. Together these findings indicate that developmental GC exposure increases apoptosis in HPAaxis‐associated brain regions in an age‐ and sex‐dependent manner. © 2012 Wiley Periodicals, Inc.
Epileptiform activity in the CA1 region of the hippocampus becomes refractory to attenuation by cannabinoids in part because of endogenous γ‐aminobutyric acid type B receptor activity
Authors: Messer Ricka D. , Levine Eric S. 
Published: March 2012

AbstractThe anticonvulsant properties of marijuana have been known for centuries. The recently characterized endogenous cannabinoid system thus represents a promising target for novel anticonvulsant agents; however, administration of exogenous cannabinoids has shown mixed results in both human epilepsy and animal models. The ability of cannabinoids to attenuate release of both excitatory and inhibitory neurotransmitters may explain the variable effects of cannabinoids in different models of epilepsy, but this has not been well explored. Using acute mouse brain slices, we monitored field potentials in the CA1 region of the hippocampus to characterize systematically the effects of the cannabinoid agonist WIN55212‐2 (WIN) on evoked basal and epileptiform activity. WIN, acting presynaptically, significantly reduced the amplitude and slope of basal field excitatory postsynaptic potentials as well as stimulus‐evoked epileptiform responses induced by omission of magnesium from the extracellular solution. In contrast, the combination of omission of magnesium plus elevation of potassium induced an epileptiform response that was refractory to attenuation by WIN. The effect of WIN in this model was partially restored by blocking γ‐aminobutyric acid type B (GABAB), but not GABAA, receptors. Subtle differences in models of epileptiform activity can profoundly alter the efficacy of cannabinoids. Endogenous GABAB receptor activation played a role in the decreased cannabinoid sensitivity observed for epileptiform activity induced by omission of magnesium plus elevation of potassium. These results suggest that interplay between presynaptic G protein‐coupled receptors with overlapping downstream targets may underlie the variable efficacy of cannabinoids in different models of epilepsy. © 2012 Wiley Periodicals, Inc.
Coherent patterns in long‐term sea‐level variability trends derived from long‐term tide gauge measurements
Authors: Vilibić Ivica , Šepić Jadranka , Gaxotte Zoran Adam 
Published: March 2012

AbstractGlobal long‐term sea‐level variability trends and regional coherence patterns were mapped based on hourly sea‐level time series data from the 29 longest operating tide gauge stations distributed worldwide. We split sea‐level variability into three frequency bands: (1) small‐scale synoptic bands (1–3 d), (2) large‐scale synoptic bands (3–10 d) and (3) planetary‐scale bands (10–100 d). We then calculated seasonal and annual trends. The most coherent result obtained involved a significant decrease in sea‐level variability over the tropical and subtropical Pacific, particularly at the synoptic scale frequencies. Several other coherent regions were found and linked to changes in the global atmosphere. Copyright © 2012 Royal Meteorological Society
Staging laparoscopy using ALA‐mediated photodynamic diagnosis improves the detection of peritoneal metastases in advanced gastric cancer
Authors: Kishi Kentaro , Fujiwara Yoshiyuki , Yano Masahiko , Inoue Masahiro , Miyashiro Isao , Motoori Masaaki , Shingai Tatsushi , Gotoh Kunihito , Takahashi Hidenori , Noura Shingo , Yamada Terumasa , Ohue Masayuki , Ohigashi Hiroaki , Ishikawa Osamu 
Published: March 2012

AbstractBackgroundThis study evaluated the usefulness of photodynamic diagnosis (PDD) using oral 5‐aminolevulinic acid (ALA) for the detection of peritoneal metastases in advanced gastric cancer.MethodFirst, the numbers of peritoneal metastatic nodules that were visible under conventional white light (WL) and ALA‐induced fluorescence (ALA‐F) were quantified in a mouse model of peritoneal metastasis to compare the tumor detection rate. Next, staging laparoscopy (SL) using ALA‐PDD was performed in 13 advanced gastric cancer patients with serosa‐invading tumors, and the detection sensitivity of ALA‐PDD was compared to the observations using WL.ResultsThe tumor detection rate using ALA‐F was significantly higher than the detection rate using WL (72% vs. 39%, respectively, P < 0.0001). Peritoneal metastases were detected in five patients using SL with ALA‐PDD, and liver metastases were detected in one patient. These metastases were confirmed using histological examination. Three metastatic lesions that were invisible under WL were detected under ALA‐F.ConclusionThis study demonstrated that SL with ALA‐PDD improved the detection sensitivity for peritoneal metastases. ALA‐PDD may be an important technique for the preoperative staging of advanced gastric cancer, and ALA‐PDD will provide useful information for the selection of therapeutic modality. J. Surg. Oncol. 2012; 106:294–298. © 2012 Wiley Periodicals, Inc.
Ageing resistance and corrosion resistance of silicone‐epoxy and polyurethane topcoats used in sea splash zone
Authors: Wang Z. Y. , Liu F. C. , Han E. H. , Ke W. 
Published: March 2012

AbstractThe silicone‐epoxy and polyurethane topcoats applied in a simulated sea splash environment were studied according to ISO20340 standard, and their properties were analyzed by differential scanning calorimetry (DSC), scanning electron microscopy (SEM), X‐ray photoelectron spectroscopy (XPS), and electrochemical impedance spectrum (EIS). Glass transition temperature (Tg) of silicone‐epoxy polymer is 7.7 °C higher than that of polyurethane polymer. Measurement of gloss and color difference demonstrates that anti‐ageing property of silicone‐epoxy topcoat is better than that of polyurethane topcoat. It is known from SEM and XPS analysis that silicone‐epoxy topcoat can retain the good morphological structure and ageing resistance after accelerated cycle ageing test. The results from EIS analysis indicate that the silicone‐epoxy topcoat has good anti‐corrosion properties. Measurement of contact angles indicates that surface tension of silicone‐epoxy topcoat is smaller than that of polyurethane topcoat before and after corrosion test.
Performance of cold sprayed Ni‐20Cr and Ni‐50Cr coatings on SA 516 steel in actual industrial environment of a coal fired boiler
Authors: Bala N. , Singh H. , Karthikeyan J. , Prakash S. 
Published: March 2012

AbstractPower plants are one of the major industries suffering from severe erosion–corrosion (E‐C) problems resulting in substantial losses. One way of tackling this problem is by the use of thermal spray coatings. In the current investigation a new emerging technique i.e. cold spray coating process was used to deposit Ni‐20Cr and Ni‐50Cr powder on SA 516 (grade 70) boiler steel. The bare as well as the coated steels were subjected to cyclic experimental studies, in the superheater zone of a coal fired boiler. Weight change, thickness loss, XRD, FE‐SEM/EDS and X‐ray mapping techniques were used to analyse the eroded‐corroded specimens. The uncoated steel showed weight gain after exposure in the actual boiler environment, whereas, for the coated steels there was initial weight loss followed by negligible weight change. Based upon thickness loss data the cold‐sprayed Ni‐50Cr coating was found to provide better E‐C resistance than the Ni‐20Cr coating.
Study of aging and electrochemical behaviour of AlLiCuMg alloys
Authors: Ghosh K. S. , Mukhopadhyay S. , Konar B. , Mishra B. 
Published: March 2012

AbstractAging study of 1441 and 8090 AlLiCuMg alloys exhibited characteristic precipitation hardening phenomena. Potentiodynamic polarisation studies carried out on various tempers of the 1441 and 8090 AlLiCuMg alloys in 3.5% NaCl, with a small amount of H2O2, and in 3.5% NaCl solution with pH 10 and 12 showed the shifting of open circuit potential (OCP) towards more negative potential and higher corrosion rate, with the increase of aging time. The OCP value has shifted anodically with addition of H2O2 in 3.5% NaCl solution. Further, passivity phenomenon has been observed for all the alloy tempers in 3.5% NaCl solution at pH 10 and 12. The observation of OCP shift towards more negative potential and the higher corrosion rate with the increase of aging time has been attributed to the presence of higher amounts of anodic δ (AlLi), S′ (Al2CuMg) and T1 (Al2CuLi) phases, studied by TEM, XRD and DSC methods.
Influences of the three‐phase boundary on the electrochemical corrosion characteristics of carbon steel under droplets
Authors: Wang Y. H. , Liu Y. Y. , Wang W. , Zhong L. , Wang J. 
Published: March 2012

AbstractThe potential/current distributions of carbon steel were investigated under 0.001 M sodium chloride droplets of various sizes using a wire beam electrode. During the corrosion process, carbon steel exhibited heterogeneous electrochemical characteristics with the major anodes located near the edge of the droplets. The three‐phase boundary (TPB) plays a vital role in determining the electrochemical distribution and the corrosion degree of carbon steel. With the increase of droplet size, the average anodic current density and the corrosion degree decreased, which is believed to be due to the decrease of the TPB length per unit area.
Effect of processing parameters on the microstructures and corrosion behaviour of high‐velocity oxy‐fuel (HVOF) sprayed Fe‐based amorphous metallic coatings
Authors: Wang Y. , Jiang S. L. , Zheng Y. G. , Ke W. , Sun W. H. , Chang X. C. , Hou W. L. , Wang J. Q. 
Published: March 2012

AbstractA FeCrMoMnWBCSi amorphous metallic coating was prepared by using high‐velocity oxy‐fuel spray. The influence of processing parameters on microstructure, porosity level, amorphous phase fraction and corrosion behaviour of the coatings was characterised by scanning electron microscopy, X‐ray diffraction, differential scanning calorimeter and electrochemical methods. The results indicated that the microstructures of the coatings were sensitive to the spray parameters considerably. Porosity and unmelted particle proportion decreased with the oxygen/fuel (O/F) ratio and increased with the powder feed rate. The trend of oxides content was opposite to the porosity and unmelted particle proportion. The coatings obtained with higher O/F ratio and lower powder feed rate exhibited higher hardness. The low coating hardness was mainly due to the high porosity especially when the porosity was higher than 1.21%. The spraying parameters strongly affected the amorphous phase fraction. There was a critical passive current density for balancing the porosity and the amorphous phase fraction. Corrosion resistance is dominant by the amorphous phase fraction when the porosity is less than 1.21%, while by porosity when it is higher than that. Open‐circuit potential, potentiodynamic polarisation and electrochemical impedance spectroscopy results showed that the coatings obtained with the O/F ratio of 4.2 and the powder feed rate of 40 g/min exhibiting the best corrosion resistance in 1 wt% sodium chloride solution.
Corrosion resistance of different steel grades in the geothermal fluid of Molasse Basin
Authors: Klapper H. S. , Bäßler R. , Sobetzki J. , Weidauer K. , Stürzbecher D. 
Published: March 2012

AbstractLong‐term corrosion resistance of carbon steels grade API L80 and API Q125 has been evaluated by means of electrochemical measurements and exposure tests in the Molasse Basin, one of the most important geothermal fluids in Europe. In addition, the localized corrosion resistance of the duplex stainless steel alloy 2205 and the austenitic stainless steel grade 316L was determined at 100 and 150 °C. In general, investigated materials showed a remarkable resistance to uniform and localized corrosion. Their corrosion behaviour at service conditions is discussed in this paper.
Corrosion inhibition of copper–phosphorus brazing alloys in tetra‐n‐butylammonium bromide aerated aqueous solution by benzotriazole
Authors: Liu S. , Guan W. W. , Yan Y. H. , Jiang R. Y. , Feng Z. P. , Song W. J. , Qin K. 
Published: March 2012

AbstractThe corrosion inhibition behavior of benzotriazole (BTA) on a brazing alloy, CuP in the non‐welded and welded conditions in 17 wt% (0.534 mol/L) tetra‐n‐butylammonium bromide (TBAB) aerated aqueous solution was investigated by potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), and scanning electron microscopy/energy dispersive X‐ray spectroscopy techniques. The experimental results showed that BTA could protect effectively copper alloys in aqueous TBAB solution. The inhibition efficiency of BTA increased with increasing inhibitor concentration from 0.1 to 6 g/L, attaining efficiencies of up to 96% calculated according to different methodologies. Corrosion current densities were lower after the melting process. Galvanic studies showed that copper behaved as the anode when coupled to its alloys. The addition of BTA caused an increase in charge transfer resistance and a decrease in the capacitance of the double layer. Adsorption of BTA in 17 wt% TBAB solution on the copper alloys' surface was found to obey the Langmuir adsorption isotherm.
Fabrication of superhydrophobic surfaces on Mg alloy substrates via primary cell corrosion and fluoroalkylsilane modification
Authors: Song J. L. , Xu W. J. , Lu Y. , Liu X. , Sun J. 
Published: March 2012

AbstractThe present work reports a simple and safe two‐step process to render magnesium (Mg) alloy surfaces superhydrophobic via primary cell corrosion and subsequently cover it with a fluoroalkylsilane (FAS) film. The surfaces were characterized by scanning electron microscopy (SEM), optical microscopy, energy‐dispersive X‐ray spectroscopy (EDS), Fourier‐transform infrared spectrophotometry (FTIR), X‐ray diffraction (XRD), and optical contact angle measurements. The power generated via the primary cell corrosion of copper and Mg alloys was also measured using a digital multimeter. The results show that micro/nanometer‐scale binary rough structures and an FAS film with a low surface energy were present on the Mg alloy surfaces, both of which confer good superhydrophobicity with a water contact angle of 162.8° and a tilting angle of 2°. The micro/nanometer‐scale binary rough structures consisted of micrometer‐scale grains, cluster‐like structures composed of nanometer‐scale needles, and network‐like structures composed of nanometer‐scale sheets. Superhydrophobicity was analyzed by the Cassie–Baxter theory. Findings show that only about 6.3% of the water surface was in contact with the Mg alloy substrates, while the remaining 93.7% was in contact with the air cushion. The unique advantage of the proposed method is that power can be generated during the machining process of the superhydrophobic surfaces on the Mg alloy substrates.
Biodegradable pH‐Dependent Thermo‐Sensitive Hydrogels for Oral Insulin Delivery
Authors: Zhang Zhe , Gao Xiaoye , Zhang Aiping , Wu Xiaowei , Chen Li , He Chaoliang , Zhuang Xiuli , Chen Xuesi 
Published: March 2012

AbstractA series of pH‐dependent thermo‐sensitive hydrogels for oral insulin delivery is designed and synthesized. In contrast to normal pH‐ and thermo‐sensitive hydrogels, the release of oral insulin from them is mainly controlled by the adjustable swelling ratios in gastric and intestinal juice with their variable pH sensitivity. The release behavior of loaded insulin depends on the swelling/shrinking transition because of the changing LCST at different pH values. The hydrogels presented are composed of PNIPAAm chains and PMAA segments and are prepared with the biodegradable acryloyl‐poly(ϵ‐caprolactone)‐2‐hydroxylethyl methacrylate as a crosslinker. The biodegradation rates of the hydrogels are directly related to their PMAA content. In vitro release of insulin from the hydrogels is investigated and the release profiles indicate that the smart hydrogels are of great promise in pH–temperature oral insulin delivery systems.
Aqueous Emulsion Polymerization of Substituted Acetylenes: Effects of Organic Solvent and Analysis of Blue Shifts and Emulsion Polymerization Mechanism
Authors: Chen Bo , Liu Xuan , Xu Chuqi , Song Ci , Luo Xiaofeng , Yang Wantai , Deng Jianping 
Published: March 2012

AbstractA series of optically active nanoparticles composed of helical substituted polyacetylene is prepared via emulsion polymerization. A specific organic solvent is required for solid substituted acetylene monomers to undergo emulsion polymerization. The effects of this organic solvent are investigated. Its amount is found to be decisive for obtaining stable polymer emulsions. The helical conformations of the substituted polyacetylenes in nanoparticle state are identified with the help of CD and UV‐vis spectra. A blue shift occurs in CD and UV‐vis spectra of some of the polyacetylene emulsions. The underlying driving force for the blue shift is discussed, and an emulsion polymerization mechanism is proposed.
Estimation of Self‐Diffusion Coefficients of Small Penetrants in Semicrystalline Polymers Using Single‐Sided NMR
Authors: Kwamen R. , Blümich B. , Adams A. 
Published: March 2012

AbstractA simple and fast way to measure proton self‐diffusion coefficients of small penetrant molecules in semicrystalline polymers is introduced. The approach takes advantage of the strong static gradient of a mobile single‐sided NMR sensor and it is demonstrated on PE samples with varying degrees of crystallinity fully saturated in either toluene or n‐hexane. The self‐diffusion coefficients were measured using the gradient stimulated echo sequence appended with a CPMG. It is also shown for the first time, with demonstration on PE plates several millimeter thick with different aging histories, that one‐dimensional profiles of self‐diffusion coefficients as a function of depth can be easily obtained.
Dietary tocopherols inhibit cell proliferation, regulate expression of ERα, PPARγ, and Nrf2, and decrease serum inflammatory markers during the development of mammary hyperplasia
Authors: Smolarek Amanda K. , So Jae Young , Thomas Paul E. , Lee Hong Jin , Paul Shiby , Dombrowski Anne , Wang Chung‐Xiou , Saw Constance Lay‐Lay , Khor Tin Oo , Kong Ah‐Ng Tony , Reuhl Kenneth , Lee Mao‐Jung , Yang Chung S. , Suh Nanjoo 
Published: March 2012

AbstractPrevious clinical and epidemiological studies of vitamin E have used primarily α‐tocopherol for the prevention of cancer. However, γ‐tocopherol has demonstrated greater anti‐inflammatory and anti‐tumor activity than α‐tocopherol in several animal models of cancer. This study assessed the potential chemopreventive activities of a tocopherol mixture containing 58% γ‐tocopherol (γ‐TmT) in an established rodent model of mammary carcinogenesis. Female ACI rats were utilized due to their sensitivity to 17β‐estradiol (E2) to induce mammary hyperplasia and neoplasia. The rats were implanted subcutaneously with sustained release E2 pellets and given dietary 0.3% or 0.5% γ‐TmT for 2 or 10 wk. Serum E2 levels were significantly reduced by the treatment with 0.5% γ‐TmT. Serum levels of inflammatory markers, prostaglandin E2 and 8‐isoprostane, were suppressed by γ‐TmT treatment. Histology of mammary glands showed evidence of epithelial hyperplasia in E2‐treated rats. Immunohistochemical analysis of the mammary glands revealed a decrease in proliferating cell nuclear antigen (PCNA), cyclooxygenase‐2 (COX‐2), and estrogen receptor α (ERα), while there was an increase in cleaved‐caspase 3, peroxisome proliferator‐activated receptor γ (PPARγ), and nuclear factor (erythroid‐derived 2)‐like 2 (Nrf2) in γ‐TmT‐treated rats. In addition, treatment with γ‐TmT resulted in a decrease in the expression of ERα mRNA, whereas mRNA levels of ERβ and PPARγ were increased. In conclusion, γ‐TmT was shown to suppress inflammatory markers, inhibit E2‐induced cell proliferation, and upregulate PPARγ and Nrf2 expression in mammary hyperplasia, suggesting that γ‐TmT may be a promising agent for human breast cancer prevention. © 2012 Wiley Periodicals, Inc.
The HMGA1 protoncogene frequently deregulated in cancer is a transcriptional target of E2F1
Authors: Massimi Isabella , Guerrieri Francesca , Petroni Marialaura , Veschi Veronica , Truffa Silvia , Screpanti Isabella , Frati Luigi , Levrero Massimo , Gulino Alberto , Giannini Giuseppe 
Published: March 2012

AbstractReactivation of the HMGA1 protoncogene is very frequent in human cancer, but still very little is known on the molecular mechanisms leading to this event. Prompted by the finding of putative E2F binding sites in the human HMGA1 promoter and by the frequent deregulation of the RB/E2F1 pathway in human carcinogenesis, we investigated whether E2F1 might contribute to the regulation of HMGA1 gene expression. Here we report that E2F1 induces HMGA1 by interacting with a 193 bp region of the HMGA1 promoter containing an E2F binding site surrounded by three putative Sp1 binding sites. Both gain and loss of function experiments indicate that Sp1 functionally interacts with E2F1 to promote HMGA1 expression. However, while Sp1 constitutively binds HMGA1 promoter, it is the balance between different E2F family members that tunes the levels of HMGA1 expression between quiescence and proliferation. Finally, we found increased HMGA1 expression in pituitary and thyroid tumors developed in Rb+/− mice, supporting the hypothesis that E2F1 is a novel important regulator of HMGA1 expression and that deregulation of the RB/E2F1 path might significantly contribute to HMGA1 deregulation in cancer. © 2012 Wiley Periodicals, Inc.