bluuebunny/crossref_metadata_2025_split huggingface dataset:
Differential regulation of GDF‐5 and FGF‐2/4 by immobilisation in ovo exposes distinct roles in joint formation
Authors: Kavanagh E. , Church V.L. , Osborne A.C. , Lamb K.J. , Archer C.W. , Francis‐West P.H. , Pitsillides A.A. 
Published: January 2006

AbstractMembers of the fibroblast growth factor (FGF) family and growth and differentiation factor 5 (GDF‐5) have been implicated in joint specification, but their roles in subsequent cavity formation are not defined. Cavity formation (cavitation) depends upon limb movement in embryonic chicks and factors involved in joint formation are often identified by their expression at the joint‐line. We have sought support for the roles of FGF‐2, FGF‐4, and GDF‐5 in cavitation by defining expression patterns, immunohistochemically, during joint formation and establishing whether these are modified by in ovo immobilisation. We found that FGF‐2 exhibited low level nuclear expression in chondrocytes and fibrocartilage cells close to presumptive joints, but showed significantly higher expression levels in cells at, and directly bordering, the forming joint cavity. This high‐level joint line FGF‐2 expression was selectively diminished in immobilised limbs. In contrast, we show that FGF‐4 does not exhibit differential joint‐line expression and was unaffected by immobilisation. GDF‐5 protein also failed to show joint‐line selective labelling, and although immobilisation induced a cartilaginous fusion across presumptive joints, it did not affect cellular GDF‐5 expression patterns. Examining changes in GDF‐5 expression in response to a direct mechanical strain stimulus in primary embryonic chick articular surface (AS) cells in vitro discloses only small mechanically‐induced reductions in GDF‐5 expression, suggesting that GDF‐5 does not exert a direct positive contribution to the mechano‐dependent joint cavitation process. This notion was supported by retroviral overexpression of UDPGD, a characteristic factor involved in hyaluronan (HA) accumulation at presumptive joint lines, which was also found to produce small decreases in AS cell GDF‐5 expression. These findings support a direct mechano‐dependent role for FGF‐2, but not FGF‐4, in the cavitation process and indicate that GDF‐5 is likely to influence chondrogenesis positively without contributing directly to joint cavity formation. Developmental Dynamics 235:826–834, 2006. © 2006 Wiley‐Liss, Inc.
IL‐7Rα expression on CD4+ T lymphocytes decreases with HIV disease progression and inversely correlates with immune activation
Authors: Koesters Sandra A. , Alimonti Judie B. , Wachihi Charles , Matu Lucy , Anzala Omu , Kimani Joshua , Embree Joanne E. , Plummer Francis A. , Fowke Keith R. 
Published: January 2006

AbstractMany factors can influence the rate of HIV disease progression, including those that maintain T cell homeostasis. One key homeostatic regulator is the IL‐7 receptor (IL‐7R). Previous studies have shown IL‐7R expression levels decrease in HIV infection, but effects on memory subtypes, CD4+ T cells, and cell function have not been explored. The present study examined the expression of the IL‐7Rα chain on naïve and memory T lymphocyte subsets of both HIV‐positive and HIV‐negative individuals from Nairobi, Kenya to assess the role of IL‐7Rα in HIV disease. Expression of IL‐7Rα was significantly reduced in all CD4+ and CD8+ T cell subsets in HIV‐positive individuals. This reduction was further enhanced in those with advanced HIV progression. Expression of IL‐7Rα was inversely correlated to immune activation, and apoptosis, and was positively correlated with CD4 count in both bivariate and multivariate analysis. Expression of IL‐7Rα did not correlate with HIV viral loads, indicating the elevated immune activation seen in HIV‐infected individuals may be impacting expression of IL‐7Rα, independent of viral loads. Signaling via the IL‐7R is essential for T cell homeostasis and maintenance of T cell memory. Reduction of this receptor may contribute to the homeostatic disruption seen in HIV.
Macrophage and T lymphocyte apoptosis during experimental pulmonary tuberculosis: their relationship to mycobacterial virulence
Authors: Ríos‐Barrera Víctor Adolfo , Campos‐Peña Victoria , Aguilar‐León Diana , Lascurain Ledesma Ricardo , Meraz‐Ríos Marco Antonio , Moreno José , Figueroa‐Granados Víctor , Hernández‐Pando Rogelio 
Published: January 2006

AbstractThe kinetics of macrophage and T lymphocyte apoptosis were determined in a well‐characterized mouse model of pulmonary tuberculosis, comparing strains of intermediate (H37Rv) and high virulence (Beijing strain, code 9501000). Both strains induced a high percentage of apoptotic activated macrophages at days 1 and 3 post infection, although this was twofold lower in Beijing‐infected mice. Progressive pneumonia started at day 14 (Beijing) or 21 (H37Rv) post infection. Pneumonic areas contained numerous macrophages with vacuolated cytoplasm (VM). In H37Rv infection few VM were apoptotic (8.7% at day 60), and the percentage was even lower in Beijing infection (1.4% at day 28). A high percentage of VM expressed the anti‐apoptotic molecule Bcl‐2 (H37Rv, 83%; Beijing, 95%). Both strains induced a progressive increase of apoptotic Th1 lymphocytes, peaking at day 60 in H37Rv infection, or 28 in Beijing infection. The peak was twofold higher in the latter. VM had strong FasL immunostaining, and confocal microscopy showed numerous apoptotic Th1 cells closely associated with them, suggesting that VM might induce apoptosis of Th1 cells. These results support the hypothesis that apoptosis of macrophages is associated with protection, while apoptosis of Th1 cells favors disease progression, and is related to the virulence of the mycobacterial strain.
CpG motif‐independent activation of TLR9 upon endosomal translocation of “natural” phosphodiester DNA
Authors: Yasuda Kei , Rutz Mark , Schlatter Beatrix , Metzger Jochen , Luppa Peter B. , Schmitz Frank , Haas Tobias , Heit Antje , Bauer Stefan , Wagner Hermann 
Published: January 2006

AbstractEndosomally translocated host (self) DNA activates Toll‐like receptor 9 (TLR9), while extracellular self‐DNA does not. This inconsistency reflects poor endosomal DNA translocation but also implies that host DNA contains DNA sequences that function as ligands for TLR9. Herein we report that contrary to phosphorothioate (PS)‐stabilized oligonucleotides (ODN), “natural” phosphodiester (PD) ODN lacking CpG motifs activate TLR9. CpG motif‐independent TLR9 activation of Flt3‐L‐induced dendritic cells (DC) was dependent on enforced endosomal translocation and triggered upregulation of CD40 and CD69 as well as production of IL‐6 and IFN‐α. Binding studies utilizing surface plasmon resonance technology (Biacore) revealed low TLR9 binding to single‐stranded (ss) PD‐ODN lacking CpG motifs. At higher concentrations their TLR9 binding activity compared well with TLR9 binding of canonical ss PD CpG‐ODN. These results imply that both the chemical modification of the DNA backbone as well as the amount of endosomally translocated DNA represent determining factors that allow CpG motif‐independent activation of TLR9 by ss PD‐DNA.
Synthesis, Structure and Reactivity in Styrene Polymerization by Heterocyclic Alkoxy‐ and Thiolatotitanium(IV) Complexes
Authors: Aragón Pedro J. , Carrillo‐Hermosilla Fernando , Villaseñor Elena , Otero Antonio , Antiñolo Antonio , Rodríguez Ana M. 
Published: January 2006

AbstractThe reaction of [Ti(OiPr)4] or [TiCl4(THF)2] with two equivalents of pyridyl alcohols or pyridyl or pyrimidinyl thiols has proven to be a good preparative method to obtain a variety of non‐metallocene diisopropoxo‐ or dichlorotitanium(IV) complexes. The complexes [Ti(X)2{2‐(OCH2)‐6‐R‐(C5H3N)}2] were found to be dynamic at room temperature, with the heterocyclic alkoxy ligand dissociating and recoordinating in a κ2‐N,O chelate fashion, as revealed by a single‐crystal X‐ray analysis of [Ti(OiPr)2{2‐(OCH2)(C5H4N)}2] (1). The dynamic behavior of some of the resulting thiolato complexes was also studied and the single‐crystal X‐ray analysis of [Ti(OiPr)2{2‐S‐4,6‐Me2‐(C4HN2)}2] (5) revealed a κ2‐N,S system for these complexes. These complexes show catalytic activity in the polymerization of styrene upon activation with methylaluminoxane. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Chromophore‐Supported Purification in Parallel Synthesis
Authors: Aumüller Ingo , Lindhorst Thisbe K. 
Published: January 2006

AbstractThe requirement for chromatographic separation and purification of product mixtures of greater or lesser degrees of complexity slows down every synthesis and is especially unfavorable when a series of parallel reactions is carried out in order to produce a library of structurally diverse compounds. To speed up chromatography, we have employed guajazulene derivatives to “dye” the starting material of a given reaction. The blue color of the chromophore‐marked reaction products facilitates visual inspection of the separation process during column chromatography, allowing many columns to be carried out in parallel. In addition to their function as color markers, the employed blue guajazulene derivatives can also be used as protecting groups during the synthesis. We have named this methodology “chromophore‐supported purification” (CSP) and have demonstrated its value in two parallel syntheses: in parallel acylations of the 6‐position of a chromophore‐marked mannoside on the one hand, and in the employment of CSP for workup after parallel 1,3‐dipolar cycloadditions between guajazulene‐marked alkynes and sugar azides on the other. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Mechanism of enantioseparation of DL‐pantothenic acid in ligand exchange capillary electrophoresis using a diol–borate system
Authors: Aizawa Sen‐ichi , Yamamoto Atsushi , Kodama Shuji 
Published: January 2006

AbstractBorate complexes formed in the ternary system at pH 9.2 containing borate, (S)‐3‐amino‐1,2‐propanediol (SAP), and DL‐pantothenic acid (DL‐PTA) were identified by 13C and 11B NMR, and it is confirmed that the binary complexes, [B(OH)2(SAP)], [B(SAP)2]+ [B(OH)2(D‐ or L‐PTA)]2−, and [B(D‐ or L‐PTA)2]3− (including [B(D‐PTA)(L‐PTA)]3−), and the ternary complexes, [B(SAP)(D‐ or L‐PTA)]−, coexist at equilibrium in the ternary system. Thermodynamic experiments by variable‐temperature 11B NMR revealed that the ternary complex, [B(SAP)(D‐PTA)]−, is entropically more stable than [B(SAP)(L‐PTA)]−. Because two geometrical isomers are possible for the respective ternary complexes, semi‐empirical molecular orbital calculations were performed by PM5, PM3, and AM1 methods in order to obtain the optimized structures. It is indicated from the calculated heats of formation and experimentally obtained thermodynamic parameters that the (S)‐isomer is more probable for the respective ternary complexes with D‐ and L‐PTA. In the optimized structure of (S)‐[B(SAP)(D‐PTA)]− in water, the SAP and D‐PTA ligands were oppositely oriented to form a rather linear structure, while the diastereomer, (S)‐[B(SAP)(L‐PTA)]−, had a folded structure. Because such a difference in the solvated structure of the ternary complexes can give a different electrophoretic velocity in CE, the enantioseparation of DL‐PTA in CE is reasonably attributed to a difference in the observed electrophoretic mobility for the equilibrated ternary systems containing the respective ternary complexes.
Recent advances in the analysis of antibiotics by capillary electrophoresis
Authors: García‐Ruiz Carmen , Marina María Luisa 
Published: January 2006

AbstractIn this review, the main aspects related to the separation of different groups of antibiotics by CE as well as the different applications reported in the literature from the beginning 2003 till May 2005 will be provided to the readers. Firstly, the experimental conditions employed to achieve the analysis of antibiotics by CE are given. Then, the main applications performed in the pharmaceutical, clinical, food, and environmental fields have been reviewed making emphasis on sample preparation requirements needed in each case. Finally, the main conclusions and future prospects in this field are presented.
Recent advances in amino acid analysis by capillary electrophoresis
Authors: Poinsot Véréna , Lacroix Marlène , Maury Delphine , Chataigne Gabrielle , Feurer Bernard , Couderc François 
Published: January 2006

AbstractThis paper describes a number of articles that have been published on amino acid analysis using CE during the period from June 2003 to May 2005. This review article follows the previous ones of Smith (Electrophoresis 1999, 20, 3078–3083), Prata et al.. (Electrophoresis 2001, 22, 4129–4138), and Poinsot et al.. (Electrophoresis 2003, 24, 4047–4062). Several new developments in amino acid analysis with CE are reported concerning UV detection, LIF, MS, and NMR. In addition, we describe articles concerning clinical and pharmaceutical studies, neuroclinical applications, and agricultural and food analysis.
A framework for CFD analysis of helicopter rotors in hover and forward flight
Authors: Steijl R. , Barakos G. , Badcock K. 
Published: January 2006

AbstractA framework is described and demonstrated for CFD analysis of helicopter rotors in hover and forward flight. Starting from the Navier–Stokes equations, the paper describes the periodic rotor blade motions required to trim the rotor in forward flight (blade flapping, blade lead‐lag and blade pitching) as well as the required mesh deformation. Throughout, the rotor blades are assumed to be rigid and the rotor to be fully articulated with separate hinges for each blade. The employed method allows for rotors with different numbers of blades and with various rotor hub layouts to be analysed. This method is then combined with a novel grid deformation strategy which preserves the quality of multi‐block structured, body‐fitted grids around the blades. The coupling of the CFD method with a rotor trimming approach is also described and implemented. The complete framework is validated for hovering and forward flying rotors and comparisons are made against available experimental data. Finally, suggestions for further development are put forward. For all cases, results were in good agreement with experiments and rapid convergence has been obtained. Comparisons between the present grid deformation method and transfinite interpolation were made highlighting the advantages of the current approach. Copyright © 2006 John Wiley & Sons, Ltd.
The role ofN‐methyl‐D‐asparate receptors in neurogenesis
Authors: Nacher Juan , McEwen Bruce S. 
Published: January 2006

AbstractThe dentate gyrus continues to incorporate granule neurons during adulthood. Among the factors that we know modulate adult neurogenesis in the dentate gyrus, one of the first studied was the influence of excitatory aminoacids. These neurotransmitters, acting through NMDA receptors, are able to modulate both the proliferation of progenitor cells as well as the rate of neurogenesis in the adult dentate gyrus. However, the mechanisms by which these processes are influenced are not clearly known. Although there is no anatomical evidence of NMDA receptor expression in adult hippocampal progenitor cells or differentiating granule neurons, electrophysiological data and in vitro studies suggest that NMDA receptors may be expressed by certain precursor cells and immature granule neurons. This review summarizes findings on the influence of pharmacological manipulation of NMDA receptors on adult neurogenesis. We also analyze previous studies that have suggested the expression of NMDA receptors in progenitors and immature granule cells and discuss the putative role of these receptors in the regulation of developmental processes such as proliferation, migration, or neurite outgrowth. © 2006 Wiley‐Liss, Inc.
Clinical significance of serum Th1‐, Th2‐ and regulatory T cells‐associated cytokines in adult T‐cell leukemia/lymphoma: High interleukin‐5 and ‐10 levels are significant unfavorable prognostic factors
Authors: Inagaki Atsushi , Ishida Takashi , Ishii Toshihiko , Komatsu Hirokazu , Iida Shinsuke , Ding Jianmin , Yonekura Kentaro , Takeuchi Shogo , Takatsuka Yoshifusa , Utsunomiya Atae , Ueda Ryuzo 
Published: January 2006

AbstractPatients with adult T‐cell leukemia/lymphoma (ATLL) are in a severely immunocompromised state. Therefore, it is assumed that ATLL cells either express particular cytokines or induce their expression in host immune cells, disrupting the balanced production of cytokines and causing the host's immune system to break down. We examined the levels of serum cytokines including T helper type 1‐ (Th1‐) associated cytokines [IFN‐γ, TNF‐α, and interleukin (IL)‐2], Th2‐associated cytokines (IL‐4, ‐5 and ‐6) and regulatory T cell‐associated cytokines (IL‐10 and TGF‐β1) in 94 ATLL patients, 39 asymptomatic human T‐cell lymphotropic virus type‐1 (HTLV‐1) carriers and 50 healthy adult volunteers, to clarify whether elevated levels of particular cytokines are associated with the prognosis of ATLL patients. On multivariate analysis, high IL‐5 and IL‐10 levels were independent and significant unfavorable prognostic factors among the ATLL patients. The IL‐10 level significantly increased with disease progression at each step from asymptomatic HTLV‐1 carrier to ATLL of the indolent variant (chronic and smoldering subtypes) to ATLL of the aggressive variant (acute and lymphoma subtypes). Furthermore, high IL‐10 was significantly associated with high lactate dehydrogenase (LDH), indicating that the IL‐10 level reflects the tumor burden. The IL‐5 level was not associated with disease progression nor LDH. Among ATLL patients with the aggressive variant, high IL‐5, but not high IL‐10, was an independent and significant unfavorable prognostic factor on multivariate analysis. Measurement of serum IL‐5 and IL‐10 levels is useful for predicting the prognosis and for determining a suitable treatment strategy for ATLL patients. © 2006 Wiley‐Liss, Inc.
Regional hypermethylation and global hypomethylation are associated with altered chromatin conformation and histone acetylation in colorectal cancer
Authors: Deng Guoren , Nguyen Anh , Tanaka Hirofumi , Matsuzaki Koji , Bell Ian , Mehta Kshama R. , Terdiman Jonathan P. , Waldman Frederic M. , Kakar Sanjay , Gum James , Crawley Suzanne , Sleisenger Marvin H. , Kim Young S. 
Published: January 2006

AbstractRegional DNA hypermethylation and global DNA hypomethylation are 2 epigenetic alterations associated with colorectal cancers. However, their correlation with microsatellite instability (MSI) and chromosomal instability (CIN) in colorectal cancer, and their relationship with chromatin conformation and histone modification are not clear. In this study, we analyzed regional and global methylation in 16 cell lines and 64 primary colorectal cancers. We found that MSI and CIN are 2 alternative events in most cell lines and tumors. Furthermore, regional hypermethylation and global hypomethylation are also alternative events in most cases. We also observed a strong correlation between MSI and regional hypermethylation and between CIN and global hypomethylation. We further analyzed chromatin conformation and histone acetylation in cell lines with CIN or MSI. CIN cancers had open chromatin conformation and enriched histone acetylation in repetitive as well as in gene‐specific regions. MSI cancers, on the other hand, had closed chromatin conformation and low levels of histone acetylation. After a MSI cell line was treated with 5‐aza‐2′‐deoxycytidine or trichostatin A, the closed chromatin conformation became open, and histone acetylation was enriched. These observations support our hypothesis that in colorectal cancer, regional hypermethylation and global hypomethylation are associated with altered chromatin conformation and histone acetylation, which might have a causal correlation with MSI and CIN, respectively. © 2006 Wiley‐Liss, Inc.
A history of cancer in the husband does not increase the risk of breast cancer
Authors: Negri Eva , Bertuccio Paola , Talamini Renato , Franceschi Silvia , Montella Maurizio , Giacosa Attilio , Pelucchi Claudio , La Vecchia Carlo 
Published: January 2006

AbstractSpouses share the home environment, and dietary and other lifestyle habits. Furthermore, a cancer diagnosis in the husband is a stressful event for the wife also. Thus, a history of cancer in the husband may be an indicator of breast cancer risk. We investigated the issue in a large Italian multicentric case‐control study on 2,588 women with incident breast cancer and 2,569 female hospital controls, admitted for acute, non neoplastic diseases. The adjusted odds ratio (OR) was 1.0 (95% confidence interval, CI, 0.7–1.4) for a history of any type of cancer in the husband, 1.0 (95% 0.4–2.7) for stomach, 0.7 (95% 0.2–2.3) for intestinal (chiefly colorectal), 0.9 (95% CI 0.5–1.7) for lung, and 1.3 (95% CI 0.4–4.3) for prostate cancer. The OR was close to unity also when data were analyzed in separate strata of patient's or husband's age, patient's education, or vital status of the husband. This study suggests that women whose husband had a diagnosis of cancer are not at increased risk of breast cancer, although results for individual cancer sites should be interpreted with caution, due to small numbers. © 2006 Wiley‐Liss, Inc.
APE1 genotype and risk of bladder cancer: Evidence for effect modification by smoking
Authors: Terry Paul D. , Umbach David M. , Taylor Jack A. 
Published: January 2006

AbstractApurinic/apyrimidinic (AP) sites are common mutagenic and cytotoxic DNA lesions that arise from the loss of normal bases. APE1, the major AP endonuclease of human cells, plays a central role in the repair of AP sites through both its endonuclease and phosphodiesterase activities. A commonAPE1polymorphism, a T→G transversion (Asp 148 Glu), was previously shown to be associated with risk of lung cancer, an association that was modified by cigarette smoking. To explore the association betweenAPE1genotype, smoking and bladder cancer risk, we examined data from an existing case–control study of bladder cancer patients (n= 239) and control individuals (n= 215) recruited from urology clinics at 2 hospitals in North Carolina. Genotype at the polymorphic site was determined using allele‐specific primer extension reactions, followed by matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry. We found no overall association betweenAPE1genotype and bladder cancer risk. In stratified analyses, however, a positive association with risk was observed with an increasing number of Glu alleles among never smokers, but not among smokers (p‐value for interaction = 0.005). We can speculate that small allelic differences that are apparent in never smokers are obscured by the large amount of DNA damage found in smokers. Given the lack of established biological mechanisms, and suboptimal numbers of subjects in some exposure categories, our findings should be interpreted cautiously. Published 2006 Wiley‐Liss, Inc.