bluuebunny/crossref_metadata_2025_split huggingface dataset:
Formulation, characterization, and in vitro evaluation of quantum dots loaded in poly(lactide)‐vitamin E TPGS nanoparticles for cellular and molecular imaging
Authors: Pan Jie , Wang Yan , Feng Si‐Shen 
Published: April 2008

AbstractWe developed a novel system of poly(lactide acid)‐d‐α‐tocopheryl polyethylene glycol 1000 succinate (PLA‐TPGS) nanoparticles (NPs) for quantum dots (QDs) formulation to improve imaging effects and reduce side effects as well as to promote a sustainable imaging. The QDs‐loaded PLA‐TPGS NPs were prepared by a modified solvent extraction/evaporation method, which were then characterized by laser light scattering (LLS) for size and size distribution; field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM) and transmission electron microscope (TEM) for surface morphology. Surface chemistry of the QDs‐loaded PLA‐TPGS NPs was analyzed by X‐ray photoelectron microscopy (XPS) and Fourier transform infra‐red spectroscopy (FTIR). Encapsulation efficiency of the QDs in the polymeric nanoparticles was measured by inductively coupled plasma optical emission spectrometry (ICP‐OES). The photostability of the QDs formulated in the PLA‐TPGS nanoparticles was investigated as changes in the florescence intensity versus the irradiation time. Confocal laser scanning microscopy (CLSM) was used to image the cellular uptake of the QDs‐loaded NPs by MCF‐7 cells. Methylthiazolyldiphenyl‐tetrazolium (MTT) assay was employed to assess the viability of MCF‐7 cells incubated with the QDs formulated by the PLA‐TPGS NPs versus the mercaptoacetic acid (MAA)‐coated QDs. It was found that the QDs formulated in the PLA‐TPGS NPs can result in higher fluorescence intensity and higher photostability than the bare QDs as well as lower cytotoxicity than the MAA‐coated QDs. Biotechnol. Bioeng. 2008;101: 622–633. © 2008 Wiley Periodicals, Inc.
Caveats in the interpretation of the surgical literature
Authors: Guller U 
Published: April 2008

Abstract
The ability to appraise research literature critically is an invaluable tool in the era of evidence-based medicine. The objective of this educational article is to highlight certain caveats that are important to those who seek to interpret the surgical literature. These caveats are illustrated with intuitive examples drawn from the field of surgery. It is hoped that the article will help surgeons to recognize the common pitfalls encountered when interpreting scientific reports. This is important if research findings are to be transferred appropriately into the realm of clinical practice.
Multivariable analysis comparing outcome after sentinel node biopsy or therapeutic lymph node dissection in patients with melanoma (Br J Surg 2007; 94: 1293–1299)
Authors: Thomas J Meirion , Hayes A 
Published: April 2008

Abstract
The Editors welcome topical correspondence from readers relating to articles published in the Journal. Responses should be sent electronically via the BJS website (www.bjs.co.uk). All letters will be reviewed and, if approved,appear on the website. A selection of these will be edited and published in the Journal. Letters must be no more than 250 words in length.
Comparison of Akt/mTOR signaling in primary breast tumors and matched distant metastases
Authors: Akcakanat Argun , Sahin Aysegul , Shaye Alexandra N. , Velasco Marco A. , Meric‐Bernstam Funda 
Published: April 2008

AbstractBACKGROUND.The Akt/mammalian target of the rapamycin (mTOR) signaling pathway represents a promising target for cancer therapy. The phosphorylation status of Akt and of mTOR's phosphorylation target eukaryotic initiation factor 4E‐binding protein 1 (4E‐BP1) is often used to assess the activity of Akt and mTOR signaling. The purpose of this study was to determine whether primary tumors differ from their metastasis in their expression of pAkt and p4E‐BP1.METHODS.Primary breast tumors and their distant metastases surgically resected from the same patients were evaluated with immunohistochemical analysis (IHC) for pAkt (Ser473) and p4E‐BP1 (Ser65). The agreement between the IHC results for the primary tumor and metastases was evaluated with Cohen kappa (κ).RESULTS.Most primary breast tumors and metastatic tumors expressed pAkt (76% of each). Of the 23 matched evaluable pairs, however, 11 (47.8%) had discordant IHC results (κ −0.31; 95% confidence interval [CI], −0.49 to −0.13). Similarly, although most of the primary and metastatic tumors were positive for p4E‐BP1 (75% and 74%), of the 23 matched evaluable pairs, 8 (47.8%) were discordant (κ 0.10; 95% CI, −0.33–0.52).CONCLUSIONS.In this series, most primary breast tumors and metastases expressed pAkt and p4E‐BP1 by IHC. Concordance between IHC findings in primary tumors and metastases was poor, however. Further work is needed to determine whether this reflects true biological heterogeneity or poor reproducibility of IHC with phosphospecific antibodies, and to identify which biomarkers can be assessed most reproducibly in primary tumors to predict activity of Akt/mTOR signaling and sensitivity to pathway inhibitors. Cancer 2008. ©2008 American Cancer Society.
Effect of Surface Decoration of CNTs on the Interfacial Interaction and Microstructure of Epoxy/MWNT Nanocomposites
Authors: Zhou Wei , Wang Bo , Zheng Yaping , Zhu Yuchan , Wang Junjun , Qi Ning 
Published: April 2008

AbstractEpoxy resin nanocomposites with different contents of multiwalled carbon nanotubes (MWNTs) are prepared. The interaction between MWNTs and the epoxy resin matrix and the microstructure and mechanical properties of the composites are systematically investigated by Fourier‐transform infrared (FTIR) spectroscopy, transmission electron microscopy, scanning electron microscopy, and positron annihilation technology. FTIR spectra reveal that two kinds of hydrogen bonds exist at the interface for the nanocomposites modified by amine, one between the epoxy group on the side chain and the NH group, and the other between the epoxy group on the alicycle and the NH group. Compared to unmodified MWNT composites, the modified MWNT composites possess better mechanical properties, which are attributed to stronger interfacial interaction resulting from an efficient load transfer from matrix to MWNTs. Positron annihilation lifetime spectroscopy is used to characterize the microstructure of the epoxy/MWNT composites. The subtransition and glass transition temperatures are determined by finite‐term positron lifetime analysis and the variation of the free‐volume size as a function of temperature. Shifts of structure transition temperatures of the composites are observed with increasing MWNT weight content. Interestingly, the continuous lifetime analysis reveals the existence of two long‐lived lifetime components above the glass transition temperature, which may be attributed to the formation of local ordered regions related to the packing density of chains.
Liquid Alkanes with Targeted Molecular Weights from Biomass‐Derived Carbohydrates
Authors: West Ryan M. , Liu Zhen Y. , Peter Maximilian , Dumesic James A. 
Published: April 2008

AbstractLiquid transportation fuels must burn cleanly and have high energy densities, criteria that are currently fulfilled by petroleum, a non‐renewable resource, the combustion of which leads to increasing levels of atmospheric CO2. An attractive approach for the production of transportation fuels from renewable biomass resources is to convert carbohydrates into alkanes with targeted molecular weights, such as C8–C15 for jet‐fuel applications. Targeted n‐alkanes can be produced directly from fructose by an integrated process involving first the dehydration of this C6 sugar to form 5‐hydroxymethylfurfural, followed by controlled formation of CC bonds with acetone to form C9 and C15 compounds, and completed by hydrogenation and hydrodeoxygenation reactions to form the corresponding n‐alkanes. Analogous reactions are demonstrated starting with 5‐methylfurfural or 2‐furaldehyde, with the latter leading to C8 and C13 n‐alkanes.
The role of FGF signaling in the establishment and maintenance of mesodermal gene expression in Xenopus
Authors: Fletcher Russell B. , Harland Richard M. 
Published: April 2008

AbstractFGF signaling is important for the formation of mesoderm in vertebrates, and when it is perturbed in Xenopus, most trunk and tail mesoderm fails to form. Here we have further dissected the activities of FGF in patterning the embryo by addressing its inductive and maintenance roles. We show that FGF signaling is necessary for the establishment of xbra expression in addition to its well‐characterized role in maintaining xbra expression. The role of FGF signaling in organizer formation is not clear in Xenopus. We find that FGF signaling is essential for the initial specification of paraxial mesoderm but not for activation of several pan‐mesodermal and most organizer genes; however, early FGF signaling is necessary for the maintenance of organizer gene expression into the neurula stage. Inhibition of FGF signaling prevents VegT activation of specific mesodermal transcripts. These findings illuminate how FGF signaling contributes to the establishment of distinct types of mesoderm. Developmental Dynamics 237:1243‐1254, 2008. © 2008 Wiley‐Liss, Inc.
Hsp60C is required in follicle as well as germline cells during oogenesis in Drosophila melanogaster
Authors: Sarkar Surajit , Lakhotia S.C. 
Published: April 2008

AbstractHsp60C gene of Drosophila melanogaster shows a dynamic spatiotemporal expression during oogenesis and seems to contribute bulk of the Hsp60 family proteins in ovarioles. Hsp60 distribution overlaps with that of F‐actin–rich membranes/structures in follicle, nurse, and egg cells throughout oogenesis. Skeletal muscle fibers associated with ovarioles and in other parts of the body show patterned location of Hsp60 in A‐bands. During stages 11–12, Hsp60 accumulates at junctions of nurse cells and oocyte, where a new microtubule organizing center is known to develop. A recessive hypomorph allele, Hsp60C1 causes complete sterility of the rare surviving homozygous adults. Their egg chambers show very little Hsp60C transcripts or Hsp60 protein. Beginning at stages 6–7, Hsp60C1 chambers show a disorganized follicle cell layer with poor cell adhesion in addition to abnormal organization of F‐actin and other cytoskeletal structures in follicle, nurse, and egg cells. Additionally, expression and localizations of Hrb98DE, Squid, and Gurken proteins in nurse cells and oocyte are also severely affected. Hsp60C1 homozygous follicle cell clones in Hsp60C1/+ ovarioles show disruptions in follicle epithelial and cytoskeleton arrangements. Likewise, egg chambers with Hsp60C1 homozygous germline clones in Hsp60C1/+ flies show abnormal oogenesis. Our results provide the first evidence for an essential role of Hsp60C in Drosophila oogenesis, especially in organization and maintenance of cytoskeletal and cell adhesion components. Developmental Dynamics 237:1334‐1347, 2008. © 2008 Wiley‐Liss, Inc.
Evolution of the thyroid: Anterior–posterior regionalization of theOikopleuraendostyle revealed byOtx,Pax2/5/8, andHox1expression
Authors: Cañestro Cristian , Bassham Susan , Postlethwait John H. 
Published: April 2008

AbstractThe thyroid in vertebrates and its homolog, the endostyle in nonvertebrate chordates, share a molecular code for dorsoventral patterning. Little is yet known, however, about mechanisms that pattern the endostyle's anterior–posterior (AP) axis. To extend our understanding of thyroid development and evolution, we studiedOikopleura dioica, a larvacean urochordate that retains a chordate body plan as adults. Transcription factor expression domains revealed AP regionalization of the endostyle, with expression ofOtxrostrally,Hox1caudally, and twoPax2/5/8paralogs centrally. Comparative analysis suggested that the endostyle of stem chordates expressed orthologs of these genes and that ancestral subfunctions partitioned differentially among lineages. Because the ordered expression ofOtx,Pax2/5/8, andHox1displays patterning in both the endodermally derived endostyle and the ectodermally derived central nervous system, we propose that this gene set belonged to the developmental genetic toolkit of stem bilaterians and repeatedly provided AP positional information in various developmental situations. Developmental Dynamics 237:1490‐1499, 2008. © 2008 Wiley‐Liss, Inc.
PAX6 dosage effects on corneal development, growth, and wound healing
Authors: Dorà Natalie , Ou Jingxing , Kucerova Romana , Parisi Ida , West John D. , Collinson J. Martin 
Published: April 2008

AbstractThe requirement for correct dosage of the transcription factor Pax6 during corneal growth and development was investigated using the Pax6‐overexpressing (PAX77) transgenic mouse. Transgenics had a microcornea phenotype due to failure of postnatal growth, associated with reduction in the number of cells layers in the corneal epithelium. Cell cycle progression was monitored using bromodeoxyuridine, p63, cyclin E, and phosphohistone‐3 labeling: proliferation rates were higher in PAX77+ than wild‐type, without a concomitant increase in apoptosis. Hence, failure of proliferation did not underlie microcornea. PAX77+ corneal epithelia had reduced levels of cytokeratin‐12, and exhibited severe wound healing delay that, in contrast to Pax6+/− mice, could not be modulated by exogenous growth factors. PAX77+ lenses showed partial failure of lens fiber differentiation. The data demonstrate that anterior eye development is very sensitive to Pax6 dosage. Although there are similarities between the eye phenotype of Pax6 heterozygotes and overexpressing mice, there are also striking differences. Developmental Dynamics 237:1295‐1306, 2008. © 2008 Wiley‐Liss, Inc.
Activation drives PD‐1 expression during vaccine‐specific proliferation and following lentiviral infection in macaques
Authors: Hokey David A. , Johnson F. Brad , Smith Jasmine , Weber Joshua L. , Yan Jian , Hirao Lauren , Boyer Jean D. , Lewis Mark G. , Makedonas George , Betts Michael R. , Weiner David B. 
Published: April 2008

AbstractRecent data supports that increased expression of PD‐1, a negative regulator of immune function, is associated with T cell exhaustion during chronic viral infection. However, PD‐1 expression during acute infection and vaccination has not been studied in great detail in primates. Here, we examine PD‐1 expression on CD3+ T cells following DNA vaccination or lentiviral infection of macaques. Ex vivo peptide stimulation of PBMC from DNA‐vaccinated uninfected macaques revealed a temporal increase in PD‐1 expression in proliferating antigen‐specific CD8+ T cells. Following the initial increase, PD‐1 expression steadily declined as proliferation continued, with a concomitant increase in IFN‐γ secretion. Subsequent examination of PD‐1 expression on T cells from uninfected and lentivirus‐infected non‐vaccinated macaques revealed a significant increase in PD‐1 expression with lentiviral infection, consistent with previous reports. PD‐1 expression was highest on cells with activated memory and effector phenotypes. Despite their decreased telomere length, PD‐1hi T cell populations do not appear to have statistically significant uncapped telomeres, typically indicative of proliferative exhaustion, suggesting a different mechanistic regulation of proliferation by PD‐1. Our data indicate that PD‐1 expression is increased as a result of T cell activation during a primary immune response as well as during persistent immune activation in macaques.Supporting Information for this article is available at www.wiley‐vch.de/contents/jc_2040/2008/37857_s.pdf
IL‐12, IL‐23, and IL‐27 enhance human β‐defensin‐2 production in human keratinocytes
Authors: Kanda Naoko , Watanabe Shinichi 
Published: April 2008

AbstractIL‐12, IL‐23, and IL‐27, which are produced by APC, modulate innate and adaptive immunities. Human β‐defensin‐2 (hBD‐2) produced by epidermal keratinocytes promotes cutaneous antimicrobial defense and inflammation. We examined the in vitro effects of IL‐12, IL‐23, and IL‐27 on hBD‐2 production in human keratinocytes. IL‐12, IL‐23, and IL‐27 enhanced IL‐1β‐induced hBD‐2 secretion and mRNA expression in keratinocytes. The stimulatory effects of IL‐12, IL‐23, and IL‐27 were suppressed by antisense oligonucleotides against NF‐κB p50 and p65. In addition, the effects of IL‐12 and IL‐27 were suppressed by antisense STAT3 and STAT1, respectively. All the three IL enhanced the basal and IL‐1β‐induced transcriptional activities of NF‐κB, while IL‐12 and IL‐27 enhanced STAT3 and STAT1 activities, respectively. Further, IL‐12, IL‐23, and IL‐27 promoted basal and IL‐1β‐induced phosphorylation of IκBα. IL‐12 and IL‐23 tyrosine phosphorylated STAT3 and STAT1, respectively; IL‐12, IL‐23, and IL‐27 tyrosine phosphorylated JAK2 and tyrosine kinase‐2; and IL‐27 tyrosine phosphorylated JAK1. These results suggest that IL‐12, IL‐23, and IL‐27 may enhance IL‐1β‐induced hBD‐2 production in keratinocytes by activating NF‐κB. STAT3 and STAT1 are involved in the effects of IL‐12 and IL‐27, respectively. Thus, IL‐12, IL‐23, and IL‐27 may promote cutaneous antimicrobial defense and inflammation via hBD‐2.
Performance‐based optimum seismic design of reinforced concrete structures
Authors: Fragiadakis Michalis , Papadrakakis Manolis 
Published: April 2008

AbstractA fully automated design methodology based on nonlinear response history analysis is proposed for the optimum seismic design of reinforced concrete (RC) structures. The conventional trial‐and‐error process is replaced by a structural optimization algorithm that serves as a search engine capable of locating the most efficient design in terms of cost and performance. Two variations of the proposed design methodology are introduced. The first approach treats the optimum design problem in a deterministic manner, while in the second variation the optimum design is sought in the framework of a reliability‐based optimization problem. The reliability‐based approach seems to be a more rational procedure since more meaningful design criteria that correlate better with the performance‐based design concept can be adopted. Thus, the practice of using the mean annual frequency of a limit‐state being exceeded to assess the candidate designs is compared with the use of deterministic criteria. Both formulations take into consideration the structural response for a number of limit‐states, from serviceability to collapse prevention. The proposed design procedure is specifically tailored to the design of RC structures, where a preliminary design step of generating tables of concrete sections is introduced. In order to handle the large size of the tables, the concept of multi‐database cascade optimization is implemented. The final design has to comply with the provisions of European design codes. The proposed methodology allows for a significant reduction of the direct construction cost combined with improved control of the seismic performance under earthquake loading. Copyright © 2008 John Wiley & Sons, Ltd.
Efficient synthesis of novel six‐member ring‐fused quinoline derivatives via the friedländer reaction
Authors: Yang Dingqiao , Guo Wei , Cai Yuepeng , Jiang Lasheng , Jiang Kailing , Wu Xiaobing 
Published: April 2008

AbstractNovel quinolines fused with a six‐member ring 5a–j were prepared in high yields (75–95%) via the Friedländer reaction of dimethoxy‐substituted o‐aminobenzaldehydes of 3a or 3b with cyclic ketones 4, respectively. The structures of 5a–j were determined by IR, 1H NMR, MS, and elemental analysis. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:229–233, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20356
Synthetic and mechanistic aspects of preparation of phosphinito‐ and phosphito‐mercuries
Authors: Nycz Jacek E. 
Published: April 2008

AbstractA >PO− (1) type of anion has been used as an efficient synthetic precursor of four‐coordinated compounds: R2P(O)Hg(O)PR2 (5) and R2P(O)HgBz (3) (R = alkoxy, alkyl, aryl). They were obtained in good yield. Bis(t‐butyl‐phenylphosphinito‐P)mercury (meso and rac) (5c,d) selectively decomposed into 1,2‐di‐t‐butyl‐1,2‐diphenyldiphosphane 1,2‐dioxide (meso and rac) (6c,d). Furthermore, some mechanistic aspects of the synthesis of mentioned compounds are elaborated.© 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:234–237, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20409
The preparation and characterization of guanylurea nitrate and perchlorate salts
Authors: Klapötke Thomas M. , Sabaté Carles Miró 
Published: April 2008

AbstractGuanylurea nitrate (GUN) and guanylurea perchlorate (GUP) were prepared from cyanoguanidine (CG) and concentrated nitric or perchloric acid, respectively. Both compounds were fully characterized by analytical and spectroscopic methods. Crystals of GUP were grown from water, and its crystal structure was determined by single‐crystal X‐ray diffraction. GUP crystallizes in the monoclinic space group P21/c with four molecules in the unit cell; different unit cell parameters are a = 8.0115(2) Å, b = 9.7328(2) Å c = 9.5770(2) Å and β = 105.89(1)°. The heats of combustion of both compounds were determined using oxygen bomb calori‐metry. Finally, the EXPLO5 computer code was used to determine the detonation velocity (D = 5734 m s−1) and pressure (P = 10.6 GPa) of GUN as well as those of formulations with ammonium nitrate and dinitramide. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:301–306, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20419
Efficient synthesis of 2‐substituted thieno[2,3‐d]pyrimidin‐4(3H)‐ones via an iminophosphorane
Authors: Fang Zheng‐Dong , Hu Yang‐Gen , Ding Ming‐Wu 
Published: April 2008

AbstractThe carbodiimides 4, obtained from reactions of iminophosphorane 3 with aromatic isocyanates, were reacted with secondary amines to give 2‐dialkylamino‐5‐ethyl‐6‐methyl‐thieno[2,3‐d]pyrimidin‐4(3H)‐ones 6 in the presence of catalytic amount of EtONa. Reactions of 4 with phenols or ROH in the presence of the catalytic amount of K2CO3 or RONa gave 2‐aryloxy‐ or 2‐alkoxy‐5‐ethyl‐6‐methyl‐thieno[2,3‐d]pyrimidin‐4(3H)‐ones 6 in satisfactory yields. The effects of the nucleophiles on cyclization have been investigated. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:266–270, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20424
Biomimetic synthesis of esters of natural amino acids
Authors: Devedjiev Ivan T. , Bairyamov Stanislav G. , Videva Vladimira S. 
Published: April 2008

AbstractA method for the synthesis of Gly, Ala, Phe, and Thr esters is proposed and considered as being a stage of possible biomimetic synthesis of peptides. The methyl esters of the said amino acids are obtained via intervention of 2‐hydroxypropyl phosphonate. The resulting aminoacyl phosphonates reacts with methanol to produce the amino acid methyl esters, with the release of phosphoric acid. The reaction is carried out at room temperature in water. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:252–255, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20427
A convenient synthesis of 2‐(1H‐1,2,4‐triazol‐1‐yl)‐2H‐1,4‐benzothiazine derivatives
Authors: Zhong Weihui , Sun Xiuling , Su Weike 
Published: April 2008

AbstractA series of 2‐(1H‐1,2,4‐triazol‐1‐yl)‐2H‐1,4‐benzothiazines were designed and synthesized by condensation of 1,2,4‐triazole‐substituted ω‐bromoacetophenones and o‐aminothiophenols with the aid of K2CO3 under mild conditions with moderate to high yields. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:332–336, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20434