bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis and properties of silver nanoparticles in chitosan‐based thermosensitive semi‐interpenetrating hydrogels
Authors: Li Guiying , Wen Quanwu , Zhang Ting , Ju Yuanyuan 
Published: May 2012

AbstractIn this article, thermosensitive poly(N‐isopropyl acrylamide‐co‐vinyl pyrrolidone)/chitosan [P(NIPAM‐co‐NVP)/CS] semi‐interpenetrating (semi‐IPN) hydrogels were prepared by redox‐polymerization using N,N‐methylenebisacrylamide as crosslinker and ammonium persulfate/N,N,N′,N′‐tetramethylethylenediamine as initiator. Highly stable and uniformly distributed Ag nanoparticles were prepared by using the semihydrogel networks as templates via in situ reduction of silver nitrate in the presence of sodium borohydride as a reducing agent. Introduction of CS improves the hydrogels swelling ratio (SR) and stabilizes the formed Ag nanoparticles in networks. Scanning electron microscopy and transmission electron microscopy revealed that Ag nanoparticles were well dispersed with diameters of 10 nm. The semi‐IPN hydrogel/Ag composites had higher SR and thermal stability than its corresponding semi‐IPN hydrogels. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Wintersweet‐Flower‐Like CoFe2O4/MWCNTs Hybrid Material for High‐Capacity Reversible Lithium Storage
Authors: Wang Ying , Park Jinsoo , Sun Bing , Ahn Hyojun , Wang Guoxiu 
Published: May 2012

AbstractCoFe2O4/multiwalled carbon nanotubes (MWCNTs) hybrid materials were synthesized by a hydrothermal method. Field emission scanning electron microscopy and transmission electron microscopy analysis confirmed the morphology of the as‐prepared hybrid material resembling wintersweet flower “buds on branches”, in which CoFe2O4 nanoclusters, consisting of nanocrystals with a size of 5–10 nm, are anchored along carbon nanotubes. When applied as an anode material in lithium ion batteries, the CoFe2O4/MWCNTs hybrid material exhibited a high performance for reversible lithium storage. In particular, the hybrid anode material delivered reversible lithium storage capacities of 809, 765, 539, and 359 mA h g−1 at current densities of 180, 450, 900, and 1800 mA g−1, respectively. The superior performance of CoFe2O4/MWCNTs hybrid materials could be ascribed to the synergistic pinning effect of the wintersweet‐flower‐like nanoarchitecture. This strategy could also be applied to synthesize other metal oxide/CNTs hybrid materials as high‐capacity anode materials for lithium ion batteries.
Inhibitory effect of luteolin on the odorant‐induced cAMP level in HEK293 cells expressing the olfactory receptor
Authors: Yoon Yeo Cho , Hwang Jin‐Teak , Sung Mi‐Jeong , Wang Shuaiyu , Munkhtugs Davaatseren , Rhyu Mee‐Ra , Park Jae‐Ho 
Published: May 2012

AbstractLuteolin is a flavonoid in many fruits and vegetables. Although luteolin has important biological functions, including antioxidant, anti‐inflammatory, antimicrobial, and neuroprotective activities, little is known about the functions of luteolin in the olfactory system. Various odorants can be detected and distinguished by using several molecular processes, including the binding of odorants to odorant receptors, activation of adenylyl cyclase (AC), changes of cyclic adenosine monophosphate (cAMP) and Ca2+ levels in olfactory sensory neurons, as well as changes in membrane potentials and the transmission of electric signals to the brain. Because AC‐cAMP signal transduction plays a pivotal role in the olfactory system, we evaluated the effects of luteolin on the AC‐cAMP pathway that had been stimulated by the odorant eugenol. We demonstrated that eugenol caused an upregulation of the cAMP level and the phosphorylation of phosphokinase A (PKA, a downstream target of cAMP) in human embryonic kidney 293 (HEK293) cells expressing the murine eugenol receptor. This upregulation significantly decreased in the presence of luteolin, suggesting that luteolin inhibited the odorant‐induced production of cAMP and affected the downstream phosphorylation of PKA.
microRNA Dysregulation in Prostate Cancer: Network Analysis Reveals Preferential Regulation of Highly Connected Nodes
Authors: Budd William T. , Weaver Danielle E. , Anderson Joe , Zehner Zendra E. 
Published: May 2012

AbstractmicroRNAs (miRNAs) are small RNAs shown to contribute to a number of cellular processes including cell growth, differentiation, and apoptosis. MiRNAs regulate gene expression of their targets post‐transcriptionally by binding to messenger RNA (mRNA), causing translational inhibition or mRNA degradation. Dysregulation of miRNA expression can promote cancer formation and progression. Research has largely focused on the function and expression of single miRNAs. However, complex physiological processes require the interaction, regulation and coordination of many molecules including miRNAs and proteins. Highly connected molecules often serve important roles in the cell. A proteinprotein interaction network of established miRNA targets confirmed these proteins to be highly connected and essential to the cell, affecting tumorigenesis, cell growth/proliferation, cellular death, cell assembly, and maintenance pathways. This analysis showed that miRNAs contribute to the overall health of the prostate, and their aberrant expression destabilized homeostatic balance. This integrative network approach can reveal important miRNAs and proteins in prostate cancer that will be useful to identify specific disease biomarkers, which may be used as targets for therapeutics or drugs in themselves.
Initiation of Radical Chain Reactions of Thiol Compounds and Alkenes without any Added Initiator: Thiol‐Catalyzed cis/trans Isomerization of Methyl Oleate
Authors: Biermann Ursula , Butte Werner , Koch Rainer , Fokou Patrice A. , Türünç Oǧuz , Meier Michael A. R. , Metzger Jürgen O. 
Published: May 2012

AbstractA kinetic study of the dodecanethiol‐catalyzed cis/trans isomerization of methyl oleate (cis‐2) without added initiator was performed by focusing on the initiation of the radical chain reaction. The reaction orders of the rate of isomerization were 2 and 0.5 for 1 and cis‐2, respectively, and an overall kinetic isotope effect kH/kD of 2.8 was found. The initiation was shown to be a complex reaction. The electron‐donor/‐acceptor (EDA) complex of dodecanethiol (1) and cis‐2 formed in a pre‐equilibrium reacts with thiol 1 to give a stearyl and a sulfuranyl radical through molecule‐assisted homolysis (MAH) of the sulfur–hydrogen bond. Fragmentation of the latter gives the thiyl radical, which catalyzes the cis/trans isomerization. A computational study of the EDA complex, MAH reaction, and the sulfuranyl radical calculated that the activation energy of the isomerization was in good agreement with the experimental result of EA=82 kJ M−1. Overall, the results may explain that the thermal generation of thiyl radicals without any initiator is responsible for many well‐known thermally initiated addition reactions of thiol compounds to alkenes and their respective polymerizations and for the low shelf‐life stability of cis‐unsaturated thiol compounds and of mixtures of alkenes and thiol compounds.
Photoreduction of Mesoporous In2O3: Mechanistic Model and Utility in Gas Sensing
Authors: Wagner Thorsten , Kohl Claus‐Dieter , Morandi Sara , Malagù Cesare , Donato Nicola , Latino Mariangela , Neri Giovanni , Tiemann Michael 
Published: May 2012

AbstractA model is proposed for the drop in electronic resistance of n‐type semiconducting indium oxide (In2O3) upon illumination with light (350 nm, 3.5 eV) as well as for the (light‐enhanced) sensitivity of In2O3 to oxidizing gases. Essential features of the model are photoreduction and a rate‐limiting oxygen‐diffusion step. Ordered, mesoporous In2O3 with a high specific surface area serves as a versatile system for experimental studies. Analytical techniques comprise conductivity measurements under a controlled atmosphere (synthetic air, pure N2) and temperature‐resolved in‐situ Fourier transform infrared (FTIR) spectroscopy. IR measurements reveal that oxygen vacancies form a donor level 0.18 eV below the conduction band.
Enantioselective Organocatalytic Michael Addition of Ketones to Alkylidene Malonates
Authors: Syu Siang‐En , Huang Chan‐Hui , Chen Ko‐Wei , Lee Chia‐Jui , Das Utpal , Jang Yeong‐Jiunn , Lin Wenwei 
Published: May 2012

ABSTRACTOrganocatalysts bearing sulfide or sulfone functions (1a, 1b, 1c, 1d) were studied for the direct asymmetric Michael addition of ketones and alkylidene malonates. The organocatalyst (S)‐2‐((naphthalen‐2‐ylthio)methyl)pyrrolidine, bearing a pyrrolidine and a sulfide moiety, showed a very high catalytic activity in the absence of additives. The reaction condition is mild, and the Michael adducts were obtained in very good enantioselectivities (up to 96%), diastereoselectivities (up to 95:5), and chemical yields (up to 95%). Chirality 24:600–605, 2012. © 2012 Wiley Periodicals, Inc.
Chaetoglobosin Vb from Endophytic Chaetomium Globosum: Absolute Configuration of Chaetoglobosins
Authors: Xue Min , Zhang Qiang , Gao Jin‐Ming , Li He , Tian Jun‐Mian , Pescitelli Gennaro 
Published: May 2012

ABSTRACTOne new cytochalasan alkaloid, chaetoglobosin Vb (1), together with two structurally related known compounds, chaetoglobosin V (2) and chaetoglobosin G (3), was isolated from the ethyl acetate extract of a culture of the endophytic fungus Chaetomium globosum, associated with the leaves of Ginkgo biloba tree. The structures of the isolated compounds were elucidated by spectroscopic methods including 1D and 2D NMR and mass spectrometry. The absolute configuration of chaetoglobosin Vb (1) was established by means of electronic circular dichroism (CD) spectroscopy, on the basis of the comparison between the CD spectrum of (+)‐1 with that calculated with time‐dependent density functional theory method for a simplified model. The correlation between compounds 1diss, 2, 3 was demonstrated by a biomimetic transformation of chaetoglobosin G (3) under mild conditions in chaetoglobosins V and Vb (1 and 2). The isolated metabolites were tested against some phytopathogens. Chirality 24:668–674, 2012. © 2012 Wiley Periodicals, Inc.
Randomized, double‐blind, placebo‐controlled trial of sulindac in individuals at risk for melanoma
Authors: Curiel‐Lewandrowski Clara , Swetter Susan M. , Einspahr Janine G. , Hsu Chiu‐Hsieh , Nagle Ray , Sagerman Paul , Tangrea Joseph , Parnes Howard , Alberts David S. , Chow Hsiao‐Hui 
Published: May 2012

AbstractBACKGROUND:Reduced melanoma risk has been reported with regular use of nonsteroidal anti‐inflammatory drugs (NSAIDs). However, the ability of NSAIDs to reach melanocytes in vivo and modulate key biomarkers in preneoplastic lesions such as atypical nevi has not been evaluated.METHODS:This randomized, double‐blind, placebo‐controlled trial of sulindac was conducted in individuals with atypical nevi (AN) to determine bioavailability of sulindac and metabolites in nevi and effect on apoptosis and vascular endothelial growth factor A (VEGFA) expression in AN. Fifty subjects with AN ≥4 mm in size and 1 benign nevus (BN) were randomized to sulindac (150 mg twice a day) or placebo for 8 weeks. Two AN were randomized for baseline excision, and 2 AN and BN were excised after intervention.RESULTS:Postintervention sulindac, sulindac sulfone, and sulindac sulfide concentrations were 0.31 ± 0.36, 1.56 ± 1.35, and 2.25 ± 2.24 μg/mL in plasma, and 0.51 ± 1.05, 1.38 ± 2.86, and 0.12 ± 0.12 μg/g in BN, respectively. Sulindac intervention did not significantly change VEGFA expression but did increase expression of the apoptotic marker cleaved caspase‐3 in AN (increase of 3 ± 33 in sulindac vs decrease of 25 ± 45 in the placebo arm, P = .0056), although significance was attenuated (P = .1103) after adjusting for baseline expression.CONCLUSIONS:Eight weeks of sulindac intervention resulted in high concentrations of sulindac sulfone, a proapoptotic metabolite, in BN but did not effectively modulate VEGFA and cleaved caspase‐3 expression. Study limitations included limited exposure time to sulindac and the need to optimize a panel of biomarkers for NSAID intervention studies. Cancer 2012. © 2012 American Cancer Society.
Fractures among long‐term survivors of childhood cancer
Authors: Wilson Carmen L. , Dilley Kimberley , Ness Kirsten K. , Leisenring Wendy L. , Sklar Charles A. , Kaste Sue C. , Stovall Marilyn , Green Daniel M. , Armstrong Gregory T. , Robison Leslie L. , Kadan‐Lottick Nina S. 
Published: May 2012

AbstractBACKGROUND:Although reductions in bone mineral density are well documented among children during treatment for cancer and among childhood cancer survivors, little is known about the long‐term risk of fracture. The objective of this study was to ascertain the prevalence of and risk factors for fractures among individuals participating in the Childhood Cancer Survivor Study (CCSS).METHODS:Analyses included 7414 ≥5‐year survivors of childhood cancer diagnosed between 1970 and 1986 who completed the 2007 CCSS follow‐up questionnaire and a comparison group of 2374 siblings. Generalized linear models stratified by sex were used to compare the prevalence of reported fractures between survivors and siblings.RESULTS:The median ages at follow‐up among survivors and siblings were 36.2 years (range, 21.2‐58.8 years) and 38.1 years (range, 18.4‐62.6 years), respectively, with a median 22.7 years of follow‐up after cancer diagnosis for survivors. Approximately 35% of survivors and 39% of siblings reported ≥1 fracture during their lifetime. The prevalence of fractures was lower among survivors than among siblings, both in males (prevalence ratio, 0.87; 95% confidence interval, 0.81‐0.94; P < .001) and females (prevalence ratio, 0.94; 95% confidence interval, 0.86‐1.04; P = .22). In multivariable analyses, increasing age at follow‐up, white race, methotrexate treatment, and balance difficulties were associated with increased prevalence of fractures among female survivors (P = .015). Among males, only smoking history and white race were associated with an increased prevalence of fracture (P < .001).CONCLUSIONS:Findings from this study indicated that the prevalence of fractures among adult survivors did not increase compared with that of siblings. Additional studies of bone health among aging female cancer survivors may be warranted. Cancer 2012. © 2012 American Cancer Society.
Cytomorphological and molecular genetic findings in pediatric thyroid fine‐needle aspiration
Authors: Monaco Sara E. , Pantanowitz Liron , Khalbuss Walid E. , Benkovich Vanessa A. , Ozolek John , Nikiforova Marina N. , Simons Jeffrey P. , Nikiforov Yuri E. 
Published: May 2012

AbstractBACKGROUND:The Bethesda System for Reporting Thyroid Cytopathology is largely based on data from adult studies. Although thyroid nodules in children are rare, the rate of malignancy is high. The authors' aim was to analyze the cytomorphology and mutational profiles in pediatric thyroid fine‐needle aspirations (FNAs).METHODS:Thyroid FNAs from patients 21 years old or younger were identified from the authors' pathology archive, categorized using the Bethesda System for Reporting Thyroid Cytopathology, and correlated with histological and molecular follow‐up.RESULTS:A total of 179 samples from 142 patients were identified, including 96 cases (54%) with histological follow‐up and 66 cases (37%) with molecular data. The diagnoses included 21 (12%) unsatisfactory, 82 (46%) negative, 43 (24%) atypia or follicular lesion of undetermined significance, 19 (11%) suspicious for follicular neoplasm, 6 (3%) suspicious for malignancy, and 8 (4%) positive for malignancy. The rate of malignancy in each category was 0%, 7%, 28%, 58%, 100%, and 100%, respectively. Of the 66 FNAs with molecular data, there were 11 (17%) positive for mutations. All mutation‐positive FNAs were papillary thyroid carcinomas (PTCs) on resection. The overall sensitivity and specificity in this population were 80% and 100%, respectively.CONCLUSIONS:This study demonstrates that thyroid FNA in children is a sensitive and highly specific tool. There was a 17% positivity rate for a genetic mutation, which correlated with malignancy in all cases. In comparison to adults, there was a higher prevalence of RET/PTC mutations and lower prevalence of BRAF mutations, which may in part explain the less aggressive nature of PTCs reported in children. Cancer (Cancer Cytopathol) 2012. © 2012 American Cancer Society.
Organization of antennal lobe‐associated neurons in adult Drosophila melanogaster brain
Authors: Tanaka Nobuaki K. , Endo Keita , Ito Kei 
Published: May 2012

AbstractThe primary olfactory centers of both vertebrates and insects are characterized by glomerular structure. Each glomerulus receives sensory input from a specific type of olfactory sensory neurons, creating a topographic map of the odor quality. The primary olfactory center is also innervated by various types of neurons such as local neurons, output projection neurons (PNs), and centrifugal neurons from higher brain regions. Although recent studies have revealed how olfactory sensory input is conveyed to each glomerulus, it still remains unclear how the information is integrated and conveyed to other brain areas. By using the GAL4 enhancer‐trap system, we conducted a systematic mapping of the neurons associated with the primary olfactory center of Drosophila, the antennal lobe (AL). We identified in total 29 types of neurons, among which 13 are newly identified in the present study. Analyses of arborizations of these neurons in the AL revealed how glomeruli are linked with each other, how different PNs link these glomeruli with multiple secondary sites, and how these secondary sites are organized by the projections of the AL‐associated neurons. J. Comp. Neurol. 520:4067–4130, 2012. © 2012 Wiley Periodicals, Inc.
Doublecortin and doublecortin‐like are expressed in overlapping and non‐overlapping neuronal cell population: Implications for neurogenesis
Authors: Saaltink Dirk‐Jan , Håvik Bjarte , Verissimo Carla S. , Lucassen P.J. , Vreugdenhil Erno 
Published: May 2012

AbstractWe have characterized the expression of doublecortin‐like (DCL), a microtubule‐associated protein involved in embryonic neurogenesis that is highly homologous to doublecortin (DCX), in the adult mouse brain. To this end, we developed a DCL‐specific antibody and used this to compare DCL expression with DCX. In the neurogenic regions of the adult brain like the subventricular zone (SVZ), the rostral migratory stream (RMS), the olfactory bulb (OB), and the hippocampus, DCL colocalizes with DCX in immature neuronal cell populations. In contrast to DCX, we also found high DCL expression in three other brain regions with suspected neurogenesis or neuronal plasticity. First, the radial glia‐like, hypothalamic tanycytes show high DCL expression that partly colocalizes with the neural stem cell marker vimentin. Second, DCL expression is found in cells of the suprachiasmatic nucleus (SCN), which lacks expression of the adult neuron marker NeuN. Third, a novel region exhibiting DCL expression is part of the olfactory tubercle where DCL is found in the neuropil of the islands of Calleja (ICj). Our findings define DCL as a novel marker for specific aspects of adult neurogenesis, which partly overlap with DCX. In addition, we propose unique roles for DCL in adult neurogenesis and we suggest high levels of neuronal plasticity in tanycytes, SCN, and ICj. J. Comp. Neurol. 520:2805–2823, 2012. © 2012 Wiley Periodicals, Inc.
Forebrain GABAergic projections from the dorsal raphe nucleus identified by using GAD67–GFP knock‐in mice
Authors: Bang Sun Jung , Commons Kathryn G. 
Published: May 2012

AbstractThe dorsal raphe nucleus (DR) contains serotonergic (5‐HT) neurons that project widely throughout the forebrain. These forebrain regions also receive innervation from non–5‐HT neurons in the DR. One of the main groups of non–5‐HT neurons in the DR is γ‐aminobutyric acid (GABA)ergic, but their projections are poorly understood due to the difficulty of labeling these neurons immunohistochemically. To identify GABAergic projection neurons within the DR in the current study, we used a knock‐in mouse line in which expression of green fluorescent protein (GFP) is controlled by the glutamic acid decarboxylase (GAD)67 promotor. Projections of GAD67–GFP neurons to the prefrontal cortex (PFC), nucleus accumbens (NAC), and lateral hypothalamus (LH) were evaluated by using retrograde tract tracing. The location of GAD67–GFP neurons projecting to each of these areas was mapped by rostrocaudal and dorsoventral location within the DR. Overall, 16% of DR neurons projecting to either the PFC or NAC were identified as GAD67–GFP neurons. GAD67–GFP neurons projecting to the PFC were most commonly found ventrally, in the rostral two‐thirds of the DR. NAC‐projecting GAD67–GFP neurons had an overlapping distribution that extended dorsally. GAD67–GFP neurons made a larger contribution to the projection of the DR to the LH, accounting for 36% of retrogradely labeled neurons, and were widespread throughout the DR. The current data indicate that DR GABAergic neurons not only may have the capacity to influence local network activity, but also make a notable contribution to DR output to multiple forebrain targets. J. Comp. Neurol. 520:4157–4167, 2012. © 2012 Wiley Periodicals, Inc.
Characterization of nitric oxide signaling pathways in the mouse retina
Authors: Blom Jan , Giove Tom , Deshpande Monika , Eldred William D. 
Published: May 2012

AbstractNitric oxide (NO) is a gaseous neuromodulator with physiological functions in every retinal cell type. NO is synthesized by several nitric oxide synthases (NOS) and often functions through its second messenger, cyclic guanosine monophosphate (cGMP), and protein kinase G (PKG). This study combined NO imaging, immunocytochemistry, biochemistry, and molecular biology to localize NO and its downstream signaling pathways in the mouse retina. Neuronal NOS (nNOS) was localized primarily in puncta in the inner plexiform layer, in amacrine cells, and in somata in the ganglion cell layer. Endothelial NOS was in blood vessels. Light‐stimulated NO production imaged with diaminofluorescein was present in somata in the inner nuclear layer and in synaptic boutons in the inner plexiform layer. The downstream target of NO, soluble guanylate cyclase (sGC), was in somata in the inner and outer nuclear layers and in both plexiform layers. Cyclic GMP immunocytochemistry was used functionally to localize sGC that was activated by an NO donor in amacrine, bipolar, and ganglion cells. Cyclic GMP‐dependent protein kinase (PKG) Iα was found in bipolar cells, ganglion cells, and both plexiform layers, whereas PKG II was found in the outer plexiform layer, amacrine cells, and somata in the ganglion cell layer. This study shows that the NO/cGMP/PKG signaling pathway is functional and widely distributed in specific cell types in the outer and inner mouse retina. A better understanding of these signaling pathways in normal retina will provide a firm basis for targeting their roles in retinal pathology. J. Comp. Neurol. 520:4204–4217, 2012. © 2012 Wiley Periodicals, Inc.