bluuebunny/crossref_metadata_2025_split huggingface dataset:
“One‐Pot” Synthesis of Chiral N‐Protected α‐Amino Acid Derived 1,2,4‐Oxadiazoles.
Authors: Braga Antonio L. , Luedtke Diogo S. , Alberto Eduardo E. , Dornelles Luciano , Severo Filho Wolmar A. , Corbellini Valeriano A. , Rosa Daiane M. , Schwab Ricardo S. 
Published: July 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Montmorillonite KSF Clay‐Promoted Synthesis of Enantiomerically Pure 5‐Substituted Pyrazoles from 2,3‐Dihydro‐4H‐pyran‐4‐ones.
Authors: Yadav J. S. , Reddy B. V. Subba , Srinivas M. , Prabhakar A. , Jagadeesh B. 
Published: July 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
New Radical Scavenging and Ultraviolet‐A Protecting Prenylated Dioxopiperazine Alkaloid Related to Isoechinulin A from a Marine Isolate of the Fungus Aspergillus.
Authors: Li Yong , Li Xifeng , Kang Jung Sook , Choi Hong Dae , Son Byeng Wha 
Published: July 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
A Photochemical Approach to Pyridopyrroloquinoline Derivatives as New Potential Anticancer Agents.
Authors: Aragon Pierre‐Jean , Yapi Ange‐Desire , Pinguet Frederic , Chezal Jean‐Michel , Teulade Jean‐Claude , Chapat Jean‐Pierre , Blache Yves 
Published: July 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Structure Elucidation of a New Diketopiperazine Sch 725418 from Micromonospora sp.
Authors: Yang Shu‐Wei , Chan Tze‐Ming , Terracciano Joseph , Loebenberg David , Chen Guodong , Patel Mahesh , Gullo Vincent , Pramanik Birendra , Chu Min 
Published: July 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Enantioselective Synthesis of Phyllanthurinolactone, a Leaf‐Closing Substance of Phyllanthus urinaria L., and Its Analogues Toward the Development of Molecular Probes.
Authors: Urakawa Yoshifumi , Sugimoto Takanori , Sato Hirotaka , Ueda Minoru 
Published: July 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Design, Synthesis and Cytotoxic Studies on the Simplified Oxy Analogue of Eleutherobin.
Authors: Chandrasekhar S. , Jagadeshwar V. , Narsihmulu Ch. , Sarangapani M. , Krishna D. R. , Vidyasagar J. , Vijay Dolly , Sastry G. Narahari 
Published: July 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Cationic Rh‐Bisphosphine‐Diolefin Compelxes as Precatalysts for Enantioselective Catalysis — What Information Do Single Crystal Structures Contain Regarding Product Chirality?
Authors: Drexler Hans‐Joachim , Zhang Songlin , Sun Ailing , Spannenberg Anke , Arrieta Antonio , Preetz Angelika , Heller Detlef 
Published: July 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
15‐Membered Triolefinic Macrocycles, Their Coordination Chemistry with Transition Metals, and the Catalytic Properties of Their Palladium Metal Complexes.
Authors: Moreno‐Manas Marcial , Pleixats Roser , Roglans Anna , Sebastian Rosa M. , Vallribera Adelina 
Published: July 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Distribution of GABA, glycine, and glutamate in neurons of the medulla oblongata and their projections to the midbrain tectum in plethodontid salamanders
Authors: Landwehr Sandra , Dicke Ursula 
Published: July 2005

AbstractIn the medulla oblongata of plethodontid salamanders, GABA‐, glycine‐, and glutamate‐like immunoreactivity (ir) of neurons was studied. Combined tracing and immunohistochemical experiments were performed to analyze the transmitter content of medullary nuclei with reciprocal connections with the tectum mesencephali. The distribution of transmitters differed significantly between rostral and caudal medulla; dual or triple localization of transmitters was present in somata throughout the rostrocaudal extent of the medulla. Regarding the rostral medulla, the largest number of GABA‐ and gly‐ir neurons was found in the medial zone. Neurons of the nucleus reticularis medius (NRM) retrogradely labeled by tracer application into the tectum revealed predominantly gly‐ir, often colocalized with glu‐ir. The NRM appears to be homologous to the mammalian gigantocellular reticular nucleus, and its glycinergic projection is most likely part of a negative feedback loop between medulla and tectum. Neurons of the dorsal and vestibular nucleus projecting to the tectum were glu‐ir and often revealed additional GABA‐ and/or gly‐ir in the vestibular nucleus. Regarding the caudal medulla, the highest density of GABA‐ and gly‐ir cells was found in the lateral zone. Differences in the neurochemistry of the rostral versus caudal medulla appear to result from the transmitter content of projection nuclei in the rostral medulla and support the idea that the rostral medulla is involved in tecto‐reticular interaction. Our results likewise underline the role of the NRM in visual object selection and orientation as suggested by behavioral studies and recordings from tectal neurons. J. Comp. Neurol. 490:145–162, 2005. © 2005 Wiley‐Liss, Inc.
Expression, synaptic localization, and developmental regulation of Ack1/Pyk1, a cytoplasmic tyrosine kinase highly expressed in the developing and adult brain
Authors: Ureña Jesús Mariano , La Torre Anna , Martínez Albert , Lowenstein Eve , Franco Neus , Winsky‐Sommerer Raphaelle , Fontana Xavier , Casaroli‐Marano Ricardo , Ibáñez‐Sabio Miguel Angel , Pascual Marta , Del Rio José Antonio , de Lecea Luis , Soriano Eduardo 
Published: July 2005

AbstractCytosolic tyrosine kinases play a critical role both in neural development and in adult brain function and plasticity. Here we isolated a cDNA with high homology to human Ack1 and mouse Tnk2. This cDNA directs the expression of a 125‐kD protein that can be autophosphorylated in tyrosines. Initially, this clone was named Pyk1 for proline‐rich tyrosine kinase (Lev et al., 1995); however, since it corresponds to the mouse homolog of Ack1, here we called it Ack1/Pyk1. In this study we show that Ack1/Pyk1 mRNA and protein is highly expressed in the developing and adult brain. The highest levels of Ack1/Pyk1 expression were detected in the hippocampus, neocortex, and cerebellum. Electron microscopy studies showed that Ack1/Pyk1 protein is expressed in these regions both at dendritic spines and presynaptic axon terminals, indicating a role in synaptic function. Furthermore, we demonstrate that Ack1/Pyk1 mRNA levels are strongly upregulated by increased neural activity, produced by intraperitoneal kainate injections. During development, Ack1/Pyk1 was also expressed in the proliferative ventricular zones and in postmitotic maturing neurons. In neuronal cultures, Ack1/Pyk1 was detected in developing dendrites and axons, including dendritic tips and growth cones. Moreover, Ack1/Pyk1 colocalized with Cdc42 GTPase in neuronal cultures and coimmunoprecipitated with Cdc42 in HEK 293T cells. Altogether, our findings indicate that Ack1/Pyk1 tyrosine kinase may be involved both in adult synaptic function and plasticity and in brain development. J. Comp. Neurol. 490:119–132, 2005. © 2005 Wiley‐Liss, Inc.
Water deprivation increases the expression of neuronal nitric oxide synthase (nNOS) but not orexin‐A in the lateral hypothalamic area of the rat
Authors: Yao Song T. , Gouraud Sabine , Paton Julian F.R. , Murphy David 
Published: July 2005

AbstractThe discovery that the lateral hypothalamic area (LHA) might be important in modulating drinking behavior and fluid balance has led to numerous studies aimed at identifying the key neurotransmitters/neuromodulators and pathways involved. While past studies have demonstrated the presence of neuronal nitric oxide synthase (nNOS) within the LHA, its role in the regulation of fluid homeostasis is not known. In light of this, and the mounting evidence suggesting a role for nitric oxide in osmotic regulation within the hypothalamus, this study sought to determine the effects of 24‐ and 72‐hours of water deprivation on nNOS protein expression within the LHA of the rat with immunohistochemistry. In euhydrated control animals we observed nNOS‐like immunoreactivity throughout all levels of the LHA. Following 24 hours of dehydration the number of nNOS‐like immunopositive neurons was significantly increased in the rostral but not the caudal regions of LHA. Seventy‐two hours of water deprivation lead to further increases in nNOS‐like immunoreactivity at different levels of the LHA. Interestingly, however, we observed increased nNOS‐like immunoreactivity in the caudal regions of the LHA that was not evident after 24 hours of water deprivation. Double‐labeling immunofluorescence histochemistry revealed that the nNOS‐like immunoreactive neurons were not colocalized with the orexin‐A‐containing neurons. These results suggest that an osmotic challenge leads to an upregulation of nNOS immunoreactivity within discrete areas of the LHA. This altered neurochemistry within the LHA further highlights the potential importance of nitric oxide and the LHA in central regulation of fluid homeostasis. J. Comp. Neurol. 490:180–193, 2005. © 2005 Wiley‐Liss, Inc.
Effective thermal actions and thermal properties of timber members in natural fires
Authors: König Jürgen 
Published: July 2005

AbstractFor the thermal analysis of structural or non‐structural timber members, using conventional simplified heat transfer models, thermal conductivity values of timber are normally calibrated to test results such that they implicitly take into account influences such as mass transport that are not included in the model. Various researchers and designers have used such effective thermal conductivity values, originally determined for standard fire exposure, to evaluate other fire scenarios such as natural fires. This paper discusses in qualitative terms some parameters that govern the burning of wood and their influence on effective conductivity values. Reviewing fire tests of timber slabs under natural fire conditions, the study explains why effective conductivity values, giving correct results for the ISO 834 standard fire scenario, should not be used in other fire scenarios. For this reason, the thermal properties of timber given in EN 1995‐1‐2 are limited to standard fire exposure. As shown by heat transfer calculations, the effective thermal conductivity of the char layer is strongly dependent on the charring rate and therefore varies during a natural fire scenario. It has also been shown that char oxidation during the decay phase in a natural fire has a significant influence on the temperature development in the timber member, since char surface temperatures exceed the gas temperature in the compartment or furnace. Using increased effective gas temperature as thermal action during the decay phase, and varying conductivity values for the char layer, fairly good agreement could be obtained regarding the temperature development in the timber member and the char depth. Copyright © 2005 John Wiley & Sons, Ltd.
Telomere dysfunction drives chromosomal instability in human mammary epithelial cells
Authors: Soler David , Genescà Anna , Arnedo Gema , Egozcue Josep , Tusell Laura 
Published: July 2005

AbstractThe development of genomic instability is an important step toward generating the multiple genetic changes required for cancer. Telomere dysfunction is one of the factors that contribute to tumorigenesis. Telomeres shorten with each cell division in the absence of telomerase. Human mammary epithelial cells (HMECs) obtained from normal human tissue demonstrate two growth phases. After an initial phase of active growth, HMECs exhibit a growth plateau termed selection. However, some cells can emerge from this growth plateau by spontaneously losing expression of the p16INK4a protein. These post‐selection HMECs are capable of undergoing an additional 20–50 population doublings in culture. Continued proliferation of these post‐selection HMECs leads to further telomere erosion, loss of the capping function, and the appearance of end‐to‐end chromosome fusions that can enter bridge‐fusion‐breakage (BFB) cycles, generating massive chromosomal instability before terminating in a population growth plateau termed agonescence. We have found that the chromosome arms carrying the shortest telomeres are those involved in telomere–telomere type rearrangements. In addition, we found that the risk of a particular chromosome being unstable differs between individuals. Most importantly, we identified sister chromatid fusion as a first event in generating genomic instability in HMECs. During post‐selection HMEC growth, double strand breaks are generated by both fused chromosomes as well as individual chromosomes with fused chromatids entering BFB cycles. These broken chromosome extremities are able to join other broken ends or eroded telomeres, producing massive chromosomal instability at the later passages of the cell culture. This article contains Supplementary Material available at http://www.interscience.wiley.com/jpages/1045‐2257/suppmat. © 2005 Wiley‐Liss, Inc.
Osteochondral repair in the rabbit model utilizing bilayered, degradable oligo(poly(ethylene glycol) fumarate) hydrogel scaffolds
Authors: Holland Theresa A. , Bodde Esther W. H. , Baggett L. Scott , Tabata Yasuhiko , Mikos Antonios G. , Jansen John A. 
Published: July 2005

AbstractIn this study, hydrogel scaffolds, based on the polymer oligo(poly(ethylene glycol) fumarate) (OPF), were implanted into osteochondral defects in the rabbit model. Scaffolds consisted of two layers—a bottom, bone forming layer and a top, cartilage forming layer. Three scaffold formulations were implanted to assess how material composition and transforming growth factor‐β1 (TGF‐β1) loading affected osteochondral repair. Critical histological evaluation and scoring of the quantity and quality of tissue in the chondral and subchondral regions of defects was performed at 4 and 14 weeks. At both time points, no evidence of prolonged inflammation was observed, and healthy tissue was seen to infiltrate the defect area. The quality of this tissue improved over time with hyaline cartilage filling the chondral region and a mixture of trabecular and compact bone filling the subchondral region at 14 weeks. A promising degree of Safranin O staining and chondrocyte organization was observed in the newly formed surface tissue, while the underlying subchondral bone was completely integrated with the surrounding bone at 14 weeks. Material composition within the bottom, bone‐forming layer did not appear to affect the rate of scaffold degradation or tissue filling. However, no bone upgrowth into the chondral region was observed with any scaffold formulation. TGF‐β1 loading in the top layer of scaffolds appeared to exert some therapeutic affect on tissue quality, but further studies are necessary for scaffold optimization. Yet, the excellent tissue filling and integration resulting from osteochondral implantation of these OPF‐based scaffolds demonstrates their potential in cartilage repair strategies. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res, 2005
A global but stable change in HeLa cell morphology induces reorganization of DNA structural loop domains within the cell nucleus
Authors: Martínez‐Ramos Isy , Maya‐Mendoza Apolinar , Gariglio Patricio , Aranda‐Anzaldo Armando 
Published: July 2005

AbstractDNA of higher eukaryotes is organized in supercoiled loops anchored to a nuclear matrix (NM). The DNA loops are attached to the NM by means of non‐coding sequences known as matrix attachment regions (MARs). Attachments to the NM can be subdivided in transient and permanent, the second type is considered to represent the attachments that subdivide the genome into structural domains. As yet very little is known about the factors involved in modulating the MAR–NM interactions. It has been suggested that the cell is a vector field in which the linked cytoskeleton‐nucleoskeleton may act as transducers of mechanical information. We have induced a stable change in the typical morphology of cultured HeLa cells, by chronic exposure of the cells to the polar compound dimethylsulfoxide (DMSO). Using a PCR‐based method for mapping the position of any DNA sequence relative to the NM, we have monitored the position relative to the NM of sequences corresponding to four independent genetic loci located in separate chromosomes representing different territories within the cell nucleus. Here, we show that stable modification of the NM morphology correlates with the redefinition of DNA loop structural domains as evidenced by the shift of position relative to the NM of the c‐myc locus and the multigene locus PRM1 → PRM2 → TNP2, suggesting that both cell and nuclear shape may act as cues in the choice of the potential MARs that should be attached to the NM. © 2005 Wiley‐Liss, Inc.
Structure and function of the upstream promotor of the human Mafbx gene: The proximal upstream promotor modulates tissue‐specificity
Authors: Zhao Weidong , Wu Yong , Zhao Jingbo , Guo Shuang , Bauman William A. , Cardozo Christopher P. 
Published: July 2005

AbstractMuscle loss has been linked to increased expression of an ubiquitin ligase termed muscle atrophy F‐box (MAFbx), a nuclear protein involved in degradation of MyoD. To gain insights into mechanisms by which the human MAFbx gene is controlled, the structure of its upstream promotor were studied, and its expression in cultured cells was characterized. Expression of MAFbx was found only in cells of muscle lineage. A reporter gene controlled by 948 bases of human MAFbx upstream promotor displayed similar cell‐type selectivity. MAFbx levels were greatly enhanced upon myogenic differentiation of C2C12 myoblasts, and differentiation markedly increased activity of a reporter gene constructed with 400 bp of upstream promotor from the MAFbx gene. The core promotor spanned approximately 160 bases beginning at −241 bp upstream of the first codon, included potential binding sites for MyoD and myogenin, and was highly conserved among mouse, rat, and humanMAFbx genes. The major transcription start site for the human MAFbx gene was 340 bases upstream of the ATG and was localized the highly conserved region of 140 bp. The findings indicate an important role for the immediate upstream promotor of the human MAFbx gene in mediating its developmental expression and tissue specificity. © 2005 Wiley‐Liss, Inc.
Angiogenesis and apoptosis in glioma: Two arenas for promising new therapies
Authors: Bögler Oliver , Mikkelsen Tom 
Published: July 2005

AbstractNew therapies for gliomas are urgently needed in view of the very marginal increase in patient survival that has been achieved over the past two decades, which is only somewhat mitigated by improvements in quality of life. Two relatively recent fields of research that hold out great promise in this area, are angiogenesis and apoptosis. Depriving growing tumors of the blood supply they need, or tipping the balance in the cancer cell towards cell death, both provide conceptually elegant approaches to therapy, with the hope of great efficacy and little toxicity. However, attempts at successfully translating exciting laboratory findings to the clinic have been slowed by the complexity of the underlying biology. In this article we examine some of the issues that have impeded progress, and examine the potential role that integrins may play as targets, with a role in both angiogenesis and apoptosis. © 2005 Wiley‐Liss, Inc.
Role of O‐linked β‐N‐acetylglucosamine modification in the subcellular distribution of alpha4 phosphoprotein and Sp1 in rat lymphoma cells
Authors: Dauphinee Shauna M. , Ma Marlene , Too Catherine K.L. 
Published: July 2005

AbstractThe mTOR alpha4 phosphoprotein is a prolactin (PRL)‐downregulated gene product that is found in the nucleus of PRL‐dependent rat Nb2 lymphoma cells. Alpha4 lacks a nuclear localization signal (NLS) and the mechanism of its nuclear targeting is unknown. Post‐translational modification by O‐linked β‐N‐acetylglucosamine (O‐GlcNAc) moieties has been implicated in the nuclear transport of some proteins, including transcription factor Sp1. The nucleocytoplasmic enzymes O‐β‐N‐acetylglucosaminyltransferase (OGT) and O‐β‐N‐acetylglucosaminidase (O‐GlcNAcase) adds or remove O‐GlcNAc moieties, respectively. If O‐GlcNac moieties contribute to the nuclear targeting of alpha4, a decrease in O‐GlcNAcylation (e.g., by inhibition of OGT) may redistribute alpha4 to the cytosol. The present study showed that alpha4 and Sp1 were both O‐GlcNAcylated in quiescent and PRL‐treated Nb2 cells. PRL alone or PRL + streptozotocin (STZ; an O‐GlcNAcase inhibitor) significantly (P ≤ 0.05) increased the O‐GlcNAc/alpha4 ratio above that in control quiescent cells. However, PRL + alloxan (ALX; an OGT inhibitor) or ALX alone did not decrease O‐GlcNAcylation of alpha4 below that of controls and alpha4 remained nuclear. In comparison, PRL (±ALX/STZ) greatly increased Sp1 protein levels, caused a significant decrease in the GlcNAc/Sp1 ratio (P ≤ 0.05, n = 3) as compared to controls and partially redistributed Sp1 to the cytosol. Finally, a 50% downregulation of OGT gene expression by small interfering RNA (i.e., siOGT) partially redistributed both alpha4 and Sp1 to the cytosol. The alpha4 protein partner PP2Ac had no detectable O‐GlcNAc moieties and its nuclear distribution was not affected by siOGT. In summary, alpha4 and Sp1 contained O‐GlcNAc moieties, which contributed to their nuclear targeting in Nb2 cells. © 2005 Wiley‐Liss, Inc.
(−)‐Epigallocatechin‐3‐gallate, a polyphenolic compound from green tea, inhibits fibroblast adhesion and migration through multiple mechanisms
Authors: Hung Chi‐Feng , Huang Tur‐Fu , Chiang Han‐Sun , Wu Wen‐Bin 
Published: July 2005

AbstractIt is increasingly evident that the stromal cells are involved in key metastatic processes of melanoma and some malignant solid tumors. (−)‐Epigallocatechin‐3‐gallate (EGCG), a polyphenolic compound from green tea, has been shown to have anti‐tumor activity, inhibiting adhesion, migration, and proliferation of tumor cells. However, little attention has been paid on its effects on stromal cells. In the present study, we determined the effects of EGCG on stromal fibroblasts. We showed that fibroblast adhesion to collagen, fibronectin, and fibrinogen were inhibited by EGCG. One of the possible mechanisms is binding of EGCG to fibronectin and fibrinogen but not to collagen. We then focused how EGCG affected fibroblast adhesion to collagen. EGCG treatment attenuated the antibody binding to fibroblast's integrin α2β1, indicating EGCG may affect the expression and affinity of integrin α2β1. Moreover, intracellular H2O2 level was decreased by EGCG treatment, suggesting that the tonic maintenance of intracellular H2O2 may be required for cell adhesion to collagen. In parallel, collagen‐induced FAK phosphorylation, actin cytoskeleton reorganization in fibroblasts, migration and matrix metalloproteinase(s) (MMPs) activity were also affected by EGCG. Tubular networks formed by melanoma cells grown on three‐dimensional Matrigel were also disrupted when fibroblasts were treated with EGCG in a non‐contact coculture system. Taken together, we provided here the first evidence that EGCG is an effective inhibitor on behaviors of the stromal fibroblasts, affecting their adhesion and migration. The inhibitory activity of EGCG may contribute to its anti‐tumor activity. The findings and concepts disclosed here may provide important basis for a further experiment towards understanding tumor–stroma interaction. © 2005 Wiley‐Liss, Inc.