bluuebunny/crossref_metadata_2025_split huggingface dataset:
Scalaradial, a Dialdehyde‐Containing Marine Metabolite That Causes an Unexpected Noncovalent PLA2 Inactivation
Authors: Monti Maria Chiara , Casapullo Agostino , Cavasotto Claudio N. , Napolitano Assunta , Riccio Raffaele 
Published: August 2007

AbstractSeveral marine terpenoids that contain at least one reactive aldehyde group, such as manoalide and its congeners, possess interesting anti‐inflammatory activities that are mediated by the covalent inactivation of secretory phospholipase A2 (sPLA2). Scalaradial, a 1,4‐dialdehyde marine terpenoid that was isolated from the sponge Cacospongia mollior, is endowed with a relevant anti‐inflammatory profile, both in vitro and in vivo, through selective sPLA2 inhibition. Due to its peculiar dialdehyde structural feature, it has been proposed that scalaradial exerts its enzymatic inactivation by means of an irreversible covalent modification of its target. In the context of our on‐going research on anti‐PLA2 natural products and their interaction at a molecular level, we studied scalaradial in an attempt to shed more light on the molecular mechanism of its PLA2 inhibition. A detailed analysis of the reaction profile between scalaradial and bee venom PLA2, a model sPLA2 that shares a high structural homology with the human synovial enzyme, was performed by a combination of spectroscopic techniques, chemical reactions (selective modifications, biomimetic reactions), and classical protein chemistry (such as proteolytic digestion, HPLC and mass spectrometry), along with molecular modeling studies. Unexpectedly, our data clearly indicated the noncovalent forces to be the leading event in the PLA2 inactivation process; thus, the covalent modification of the enzyme emerges as only a minor side event in the ligand–enzyme interaction. The overall picture might be useful in the design of SLD analogues as new potential anti‐inflammatory compounds that target sPLA2 enzymes.
Transient early embryonic expression of Nkx2‐5 mutations linked to congenital heart defects in human causes heart defects in Xenopus laevis
Authors: Bartlett Heather L. , Sutherland Lillian , Kolker Sandra J. , Welp Chelsea , Tajchman Urszula , Desmarais Vera , Weeks Daniel L. 
Published: August 2007

AbstractNkx2‐5 is a homeobox containing transcription factor that is conserved and expressed in organisms that form hearts. Fruit flies lacking the gene (tinman) fail to form a dorsal vessel, mice that are homozygous null for Nkx2‐5 form small, deformed hearts, and several human cardiac defects have been linked to dominant mutations in the Nkx2‐5 gene. The Xenopus homologs (XNkx2‐5) of two truncated forms of Nkx2‐5 that have been identified in humans with congenital heart defects were used in the studies reported here. mRNAs encoding these mutations were injected into single cell Xenopus embryos, and heart development was monitored. Our results indicate that the introduction of truncated XNkx2‐5 variants leads to three principle developmental defects. The atrial septum and the valve of the atrioventricular canal were both abnormal. In addition, video microscopic timing of heart contraction indicated that embryos injected with either mutant form of XNkx2‐5 have conduction defects. Developmental Dynamics 236:2475–2484, 2007. © 2007 Wiley‐Liss, Inc.
Zebrafish homologue irx1a is required for the differentiation of serotonergic neurons
Authors: Cheng Chi Wa , Yan Carol Hiu Mei , Choy Siu Wah , Hui Michelle Nga Yu , Hui Chi‐Chung , Cheng Shuk Han 
Published: August 2007

AbstractSerotonergic (5HT) neurons produce neurotransmitter serotonin, which modulates various neuronal circuits. The specification and differentiation of 5HT neurons require both extrinsic signals such as Shh and Fgf, as well as intrinsic transcription factors such as nkx2.2, mash1, phox2b, Gata2, and pet1. In this study, we show that iroquois homeodomain factor irx1a, but not irx1b, is expressed in the 5HT neurons. Knockdown of irx1a by antisense morpholino nucleotides reveals that it is a critical determinant for the differentiation of 5HT neurons in the hindbrain. However, irx1a morphants do not show a reduction of the progenitors of 5HT neurons. Hence, irx1a is not required for the initial specification but it is required for the complete differentiation of 5HT neurons. Developmental Dynamics 236:2661–2667, 2007. © 2007 Wiley‐Liss, Inc.
Sclerotomal origin of smooth muscle cells in the wall of the avian dorsal aorta
Authors: Wiegreffe Christoph , Christ Bodo , Huang Ruijin , Scaal Martin 
Published: August 2007

AbstractThe dorsal aorta is the earliest formed intraembryonic blood vessel. It is composed of an inner lining consisting of endothelial cells and an outer wall consisting of smooth muscle cells (SMCs) and fibrocytes. Aortic SMCs have been suggested to arise from several developmental lineages. Cephalic neural crest provides SMCs of the proximal part of the aorta, and SMCs of the distal part are derived from the paraxial mesoderm. Here, we show by using quail‐chick chimerization that in the avian embryo, SMCs in the wall of the dorsal aorta at trunk level arise from the sclerotome. Our findings indicate a two‐step process of aortic wall formation. First, non‐paraxial mesoderm‐derived mural cells accumulate at the floor of the aorta. We refer to these cells as primary SMCs. Second, SMCs from the sclerotome are recruited to the roof and sides of the aorta, eventually replacing the primary SMCs in the aortic floor. Developmental Dynamics 236:2578–2585, 2007. © 2007 Wiley‐Liss, Inc.
Integrin α5 is required for somite rotation and boundary formation in Xenopus
Authors: Kragtorp Katherine A. , Miller Jeffrey R. 
Published: August 2007

AbstractThe morphogenesis of somites in Xenopus laevis is characterized by a complex process of cell turning that requires coordinated regulation of cell shape, adhesion, and motility. The integrin α5 subunit has been implicated in the formation of somite boundaries in organisms utilizing epithelialization to create morphologically distinct somites, but its function has not been examined in Xenopus. We used a splice‐blocking morpholino to knock down expression of integrin α5 during somite formation. Loss of integrin α5 delayed somite turning and accumulation of integrin β1 at somite boundaries, and disrupted the fibronectin matrix surrounding developing somites. Irregular somite boundaries with a sparse and discontinuous fibronectin matrix formed upon eventual completion of somite turning. Recovery of somite morphology was improved, but still incomplete in far posterior somites. These data demonstrate that the role of integrin α5 in somite boundary formation is conserved in a species using a unique mechanism of somitogenesis. Developmental Dynamics 236:2713–2720, 2007. © 2007 Wiley‐Liss, Inc.
On the Mechanism of Palladium‐Catalyzed Cross‐Coupling of Diazonium Salts with Aryltrifluoroborates: A Combined ESI‐MS/NMR Study
Authors: Taccardi Nicola , Paolillo Rossella , Gallo Vito , Mastrorilli Piero , Nobile Cosimo F. , Räisänen Minna , Repo Timo 
Published: August 2007

AbstractA combined ESI‐MS/NMR mechanistic study on the palladium‐catalysed cross‐coupling reaction between aryldiazonium salts and aryltrifluoroborates with bis(μ‐acetato)bis(4,4′‐difluoroazobenzene‐C2,N)dipalladium(II) (4) as the precatalyst is reported. The reaction follows a Pd0/PdII cycle after reduction of 4 to a molecular Pd0 species (I), which according to the combined ESI‐MS and 19F NMR studies, bears an arylated azobenzene ligand. Oxidative addition by the diazonium salt generates the arylpalladium(II) intermediate (II), which was also detected in solution. The catalytic cycle is completed with a transmetallation between II and theorganoborate, which is followed by fast reductive elimination of the cross‐coupling product to restore the molecular Pd0 species I. A concurrent activation path was also observed which consists of the formation of (4,4′‐difluoroazobenzene‐C2,N)dipalladium(II) tetrafluoroborate (7) by the reaction of 4 with the diazonium salt and subsequent reduction by the aryltrifluoroborate to give I. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Identification of cis‐12,cis‐15 octadecadienoic acid and other minor polyenoic fatty acids in ruminant fat
Authors: Alves Susana P. , Bessa Rui J. B. 
Published: August 2007

AbstractThe fatty acid pattern of ruminant edible fats is very complex and its diversity is mostly determined by extensive interactions between dietary factors and rumen metabolism. Characterization of intermediates of polyunsaturated fatty acid (PUFA) biohydrogenation in lipids from ruminants, particularly when supplemented with oils, can be a rather difficult task. In this study, we characterized some minor PUFA that occur in muscle samples from linseed oil‐fed lambs, by covalent adduct chemical ionization tandem mass spectrometry (CACI‐MS/MS) using acetonitrile as reagent of chemical ionization. Two minor metabolites, cis‐12,cis‐15 18:2 and cis‐9,trans‐11,cis‐15 18:3 were identified for the first time in lamb meat through CACI‐MS/MS. However, the cis‐9,trans‐11,cis‐15 18:3 isomer was incompletely resolved from 20:3n‐9 under our GC/MS conditions. Thus, in studies reporting biohydrogenation intermediates in meat, caution must be taken in order to ensure proper resolution of these two fatty acid methyl esters (FAME) and therefore avoid quantitative overestimations. CACI‐MS/MS was a powerful and rapid method for the structural characterization of minor polyenoic FAME present in ruminant fat, and it seems to be a good alternative to classic 4,4‐dimethyloxazoline and picolinyl derivatization methods.
Monitoring long‐memory air quality data using ARFIMA model
Authors: Pan Jeh‐Nan , Chen Su‐Tsu 
Published: August 2007

AbstractStatistical control chart is commonly used in the industry to help ensure stability of manufacturing process and it can also be used to monitor the environmental data, such as industrial waste or effluent of manufacturing process. However, control chart needs to be modified if the set of environmental data exhibits the property of long memory. In this paper, a control chart for autocorrelated data using autoregressive fractionally integrated moving‐average (ARFIMA) model is proposed to monitor the long‐memory air quality data. Finally, we use the air quality data of Taiwan as examples to compare the difference between ARFIMA and autoregressive integrated moving‐average (ARIMA) models. The results show that residual control charts using ARFIMA models are more appropriate than those using ARIMA models. Copyright © 2007 John Wiley & Sons, Ltd.
Epidemiologic findings on serologically defined chronic atrophic gastritis strongly depend on the choice of the cutoff‐value
Authors: Brenner Hermann , Rothenbacher Dietrich , Weck Melanie N. 
Published: August 2007

AbstractChronic atrophic gastritis (CAG), a precursor of intestinal gastric cancer, is mostly ascertained noninvasively by serum pepsinogens in epidemiologic studies. However, serological definitions vary widely. We aimed to investigate the impact of this variation on estimated prevalence of CAG and its association with its main risk factors, age and Helicobacter pylori infection. Serum pepsinogen I and II and antibodies against H. pylori were measured by ELISA among 9,444 women and men aged 50–74 years in a population‐based cohort study in Saarland/Germany. Application of the various definitions resulted in a wide range of prevalence estimates of CAG prevalence (2.1%–8.2%, with an outlier of 18.8% for one particular definition) and its associations with age and H. pylori infection (age adjusted odds ratios, OR, for CagA positive H. pylori infection: 0.98–4.48). Definitions of CAG based on both pepsinogen I and the pepsinogen I/II ratio or on the pepsinogen I/II ratio only revealed much clearer associations with both age and H. pylori infection than definitions of CAG based on pepsinogen I only (ORs for H. pylori infection: 1.45–4.48 and 0.86–1.30, respectively). Epidemiologic findings on CAG lack comparability due to the heterogeneity in serologic definitions of CAG. The association of age and H. pylori infection with CAG may be strongly underestimated in studies in which CAG is defined by pepsinogen I only. © 2007 Wiley‐Liss, Inc.
Fruit and vegetable intake and esophageal cancer in a large prospective cohort study
Authors: Freedman Neal D. , Park Yikyung , Subar Amy F. , Hollenbeck Albert R. , Leitzmann Michael F. , Schatzkin Arthur , Abnet Christian C. 
Published: August 2007

AbstractChanging patterns of esophageal squamous cell carcinoma (ESCC) and esophageal adenocarcinoma (EAC) incidence worldwide suggest distinct etiologies. Although associations between fruit and vegetable intake and both ESCC and EAC have been found in multiple ecological and case–control studies, few prospective studies have investigated these associations. We prospectively examined these associations in 490,802 participants of the National Institutes of Health (NIH)‐AARP Diet and Health Study using Cox models adjusted for age, alcohol intake, body mass index, cigarette smoking, education, physical activity and total energy intake. We present hazard ratios and 95% confidence intervals per serving per 1,000 calories. During 2,193,751 person years of follow‐up, 103 participants were diagnosed with ESCC and 213 participants with EAC. We found a significant inverse association between total fruit and vegetable intake and ESCC risk (HR: 0.78, 95% CI: 0.67–0.91), but not EAC risk (0.98, 0.90–1.08). In models mutually adjusted for fruit and vegetable intake, the protective association with ESCC was stronger for fruits (0.73, 0.57–0.93) than for vegetables (0.84, 0.66–1.07). When we examined botanical subgroups, we observed significant protective associations for ESCC and intake of Rosacea (apples, peaches, nectarines, plums, pears and strawberries) and Rutaceae (citrus fruits). A significant inverse association between EAC and Chenopodiaceae (spinach) intake was observed. Results from our study suggest that the relation of fruit and vegetable intake and esophageal cancer risk may vary by histologic type. © 2007 Wiley‐Liss, Inc.
Occupational exposure to meat and risk of lymphoma: A multicenter case‐control study from Europe
Authors: Moore Tina , Brennan Paul , Becker Nikolaus , de Sanjosé Silvia , Maynadié Marc , Foretova Lenka , Cocco Pierluigi , Staines Anthony , Nieters Alexandra , Font Rebecca , Mannetje Andrea 't , Benhaim‐Luzon Véronique , Boffetta Paolo 
Published: August 2007

AbstractSeveral studies have suggested an increased risk of lymphoma among workers exposed to meat, without conclusive evidence. We conducted a multicenter case‐control study during 1998–2004 in the Czech Republic, France, Germany, Ireland, Italy and Spain, including 2,007 cases of non‐Hodgkin lymphoma, 339 cases of Hodgkin lymphoma and 2,462 controls. We collected detailed information on occupational history and assessed exposure to meat in general and several types of meat via expert assessment of the questionnaires. The odds ratio (OR) of non‐Hodgkin lymphoma for ever occupational exposure to meat was 1.18 (95% confidence interval [CI] 0.95–1.46), that for exposure to beef meat was 1.22 (95% CI 0.90–1.67), and that for exposure to chicken meat was 1.19 (95% CI 0.91–1.55). The ORs were higher among workers with longer duration of exposure. An increased risk among workers exposed to beef meat was mainly apparent for diffuse large B‐cell lymphoma (OR 1.49, 95%CI 0.96–2.33), chronic lymphocytic leukemia (OR 1.35, 95% CI 0.78–2.34) and multiple myeloma (OR 1.40, 95%CI 0.67–2.94). The latter 2 types were also associated with exposure to chicken meat (OR 1.55, 95% CI 1.01–2.37, and OR 2.05, 95%CI 1.14–3.69). Follicular lymphoma and T‐cell lymphoma, as well as Hodgkin lymphoma did not show any increase in risk. Occupational exposure to meat does not appear to represent an important risk factor of lymphoma, although an increased risk of specific types of non‐Hodgkin lymphoma cannot be excluded. © 2007 Wiley‐Liss, Inc.
Functional and phenotypic characteristics of CD4+CD25highFoxp3+ Treg clones obtained from peripheral blood of patients with cancer
Authors: Strauss Laura , Bergmann Christoph , Whiteside Theresa L. 
Published: August 2007

AbstractCirculating human CD4+CD25highFoxp3+ T cell populations (Treg) may contain activated CD4+CD25+ T cells interfering with Treg evaluation. To gain insights into the phenotypic and functional characteristics of Treg in patients with cancer, we have analyzed CD4+CD25high populations at the clonal level. Single‐cell sorted (SCS) CD4+CD25high T cells obtained from PBMC of normal controls (NC) or patients with squamous cell carcinoma of the head and neck (HNSCC) were plated at 1 cell/well in 96 well plates and expanded with anti‐CD3/anti‐CD28 Abs and 1,000 IU IL‐2/mL in the presence or absence of rapamycin (1 nM). All generated clones were evaluated for the phenotype by flow cyometry and suppressor function in CFSE‐based proliferation assays. Clones had heterogeneous CD25 expression levels. Cloning efficiency of CD4+CD25high T cells was low. CD25high clones expressed CTLA‐4, Foxp3, CD62L, but little GITR and suppressed proliferation of autologous CD4+CD25− responder cells. Clones of activated CD4+CD25interm./low cells expressed intermediate to high levels of GITR and HLA‐DR and did not suppress proliferation of responder cells. The number, suppressor phenotype and function of CD25high Treg clones were significantly enhanced in HNSCC patients relative to NC (p ≤ 0.001). CD4+CD25+ populations comprise phenotypically and functionally distinct subsets of CD25+ cells. Only a small fraction of these activated CD4+ T cells are potent suppressor cells characterized by high expression levels of CD25, Foxp3, CTLA‐4 and CD62L. The number of expandable Treg is increased in HNSCC patients. © 2007 Wiley‐Liss, Inc.
Patients with renal cell carcinoma nodal metastases can be accurately identified: External validation of a new nomogram
Authors: Hutterer Georg C. , Patard Jean‐Jacques , Perrotte Paul , Ionescu Constantin , de La Taille Alexandre , Salomon Laurent , Verhoest Gregory , Tostain Jacques , Cindolo Luca , Ficarra Vincenzo , Artibani Walter , Schips Luigi , Zigeuner Richard , Mulders Peter F. , Valeri Antoine , Chautard Denis , Descotes Jean‐Luc , Rambeaud Jean‐Jacques , Mejean Arnaud , Karakiewicz Pierre I. 
Published: August 2007

AbstractOutcome of patients with renal cell carcinoma nodal metastases (NM) is substantially worse than that of patients with localized disease. This justifies more thorough staging and possibly more aggressive treatment in those at risk of or with established NM. We developed and externally validated a nomogram capable of highly accurately predicting renal cell carcinoma NM in patients without radiographic evidence of distant metastases. Age, symptom classification, tumour size and the pathological nodal stage were available for 4,658 individuals. The data of 2,522 (54.1%) individuals from 7 centers were used to develop a multivariable logistic regression model‐based nomogram predicting the individual probability of NM. The remaining data from 2,136 (45.9%) patients from 5 institutions were used for external validation. In the development cohort, 107/2,522 (4.2%) had lymph node metastases vs. 100/2,136 (4.7%) in the external validation cohort. Symptom classification and tumour size were independent predictors of NM in the development cohort. Age failed to reach independent predictor status, but added to discriminant properties of the model. A nomogram based on age, symptom classification and tumour size was 78.4% accurate in predicting the individual probability of NM in the external validation cohort. Our nomogram can contribute to the identification of patients at low risk of NM. This tool can help to risk adjust the need and the extent of nodal staging in patients without known distant metastases. More thorough staging can hopefully better select those in whom adjuvant treatment is necessary. © 2007 Wiley‐Liss, Inc.
Enhancement of cellular binding efficiency and cytotoxicity using polyethylene glycol base triblock copolymeric nanoparticles for targeted drug delivery
Authors: Yang Jaemoon , Cho Eun‐Jin , Seo Sungbaek , Lee Jae‐Won , Yoon Ho‐Geun , Suh Jin‐Suck , Huh Yong‐Min , Haam Seungjoo 
Published: August 2007

AbstractFolate (FA) conjugated tri‐block copolymers were prepared by bioconjugation of poly ε‐caprolactonediol and various molecular weights of diamine polyethylene glycol. The synthetic tri‐block copolymers were characterized by 1H‐NMR. Three types of nanoparticles were prepared by nanoprecipitation. Their size and morphology were verified by laser scattering and transmission electron microscopy, respectively. The colloidal stability of the nanoparticles was evaluated by turbidity test. The anticancer drug doxorubicin (DOX) was encapsulated in the nanoparticles during preparation. Drug loading amounts and release behavior from prepared nanoparticles were investigated. Fluorescent‐activated cell sorting analysis and epi‐fluorescencic microscopic imaging of prepared nanoparticles exhibited good cellular uptake against target cells. FA receptor expressed OVCAR3 cells that showed higher mean fluorescence intensity than FA receptor defect A549 cells at specific polyethylene glycol chain lengths. The cell cytotoxicity of prepared nanoparticles was evaluated for receptor mediated drug delivery. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
DNA nanoparticles encapsulated in 3D tissue‐engineered scaffolds enhance osteogenic differentiation of mesenchymal stem cells
Authors: Hosseinkhani Hossein , Hosseinkhani Mohsen , Gabrielson Nathan P. , Pack Daniel W. , Khademhosseini Ali , Kobayashi Hisatoshi 
Published: August 2007

AbstractIn this study, we enhanced the expression of a plasmid DNA in mesenchymal stem cells (MSC) by the combination of three‐dimensional (3D) tissue‐engineered scaffold and nonviral gene carrier. To function as an enhanced delivery of plasmid DNA, acetic anhydride was reacted with polyethylenimine (PEI) to acetylate 80% of the primary and 20% of the secondary amines (PEI‐Ac80). This acetylated PEI has been demonstrated to show enhanced gene‐delivery efficiency over unmodified PEI. Collagen sponges reinforced by incorporating of poly(glycolic acid) (PGA) fibers were used as the scaffold material. DNA nanoparticles formed through simple mixing of plasmid DNA encoding bone morphogenetic protein‐2 (BMP‐2) and PEI‐Ac80 solutions were encapsulated within these scaffolds. MSC were seeded into each scaffold and cultured for several weeks. Within these scaffolds, the level of BMP‐2 expression by transfected MSC was significantly enhanced compared to MSC transfected by DNA nanoparticles in solution (in 2D tissue culture plates). Homogeneous bone formation was histologically observed throughout the sponges seeded with transfected MSC by using DNA nanoparticles after subcutaneous implantation into the back of rats. The level of alkaline phosphatase activity and osteocalcin content at the implanted sites of sponges seeded with transfected MSC by using DNA nanoparticles were significantly higher when compared with those seeded with other agents. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res 2008