bluuebunny/crossref_metadata_2025_split huggingface dataset:
Lanthanide Complexes with a Calix[8]arene Bearing Phosphinoyl Pendant Arms
Authors: Puntus Lada N. , Chauvin Anne‐Sophie , Varbanov Sabi , Bünzli Jean‐Claude G. 
Published: April 2007

AbstractThe phosphinoyl‐substituted macrocyclic receptor B8bL8, derived from p‐tert‐butylcalix[8]arene, was synthesized and its structure was studied in solution. According to temperature‐dependent 1H and 31P NMR spectroscopic data, the calix[8]arene adopts a so‐called in–out cone conformation. To investigate the influence of the narrow rim substitution, interaction with trivalent lanthanide ions, LnIII (Ln = La, Eu, Tb, Lu), was probed by MS, UV/Vis and NMR spectroscopic titrations. Although both 1:1 (in the presence of triflate) and 2:1 (in the presence of nitrate) Ln:B8bL8 complexes could be isolated in the solid state, the major species present in methanol is the 1:1 complex, irrespective of the anion. NMR spectroscopic data point to a common conformation for the 1:1 complexes in solution, the lanthanide ions being coordinated by four of the eight phosphinoyl arms, with a coordination sphere completed by methanol molecules or by nitrate ions, as ascertained by IR and MS spectra. The ligand displays a weak absorption at 360 nm that can be assigned to an intraligand charge‐transfer (ILCT) state, which is very sensitive to coordination. Photophysical data of the EuIII 2:1 complex point to both metal ion sites providing a very similar chemical environment for the lanthanide ions, with no coordinated water, which is contrary to what is observed for the 1:1 complex. The use of optical electronegativity to predict the energy of the charge‐transfer states in the lanthanide systems with inequivalent ligands is discussed and extensive analysis of the vibronic satellites of the Eu(5D0→7FJ) transitions ascertains conclusions drawn on the EuIII coordination. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Synthesis of Chiral Imidazolinium Carbene from a Carbohydrate and Its Rhodium(I) Complex
Authors: Shi Ji‐cheng , Lei Ni , Tong Qingsong , Peng Yiru , Wei Junfa , Jia Li 
Published: April 2007

AbstractA chiral imidazolinium salt with two bulky carbohydrate subunits, N,N′‐1,3‐bis(methyl 4,6‐O‐benzylidene‐3‐deoxy‐α‐D‐altropyrano‐3‐yl)imidazolinium chloride (4), was synthesized in high yield. Deprotonation of 4 with sodium tert‐butoxide in the presence of [RhCl(COD)]2 produced NHC‐coordinated rhodium complex 5 along with water adduct 6 to a lesser extent depending on the moisture content of the reaction mixture. These compounds were fully characterized by IR, MS, and 1H and 13C{1H} NMR spectroscopy.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
A 1,10‐Phenanthroline‐Containing Ring Connected to a Porphyrin by a Rigid Aromatic Spacer and Its Copper‐Complexed Pseudorotaxane
Authors: Frey Julien , Dobbs William , Heitz Valérie , Sauvage Jean‐Pierre 
Published: April 2007

AbstractA condensation reaction involving a free base tetraarylporphyrin‐2,3‐dione, a macrocyclic compound containing a 1,10‐phenanthroline‐5,6‐dione and a 1,2,4,5‐tetraminobenzene as a linker affords the corresponding conjugate in good yield. The porphyrin ring and the phenanthroline fragment of the other ring are connected in such a way that mutual rotation between these two groups is prohibited. Metallation of the porphyrinic site affords the corresponding zinc complex. By reacting this zinc porphyrin with copper(I), followed by the addition of the bidentate chelate 2,9‐bis(p‐anisyl)‐1,10‐phenanthroline, the threading reaction leading to the corresponding pseudorotaxane takes place quantitatively. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Acetylide Addition to Bridging Vinyliminium Ligands in Dinuclear Complexes (Eur. J. Inorg. Chem. 13/2007)
Authors: Busetto Luigi , Marchetti Fabio , Zacchini Stefano , Zanotti Valerio 
Published: April 2007

AbstractThe cover picture shows the crystal structures of three diiron complexes with bridging hydrocarbyl ligands of increasing size and complexity: from the bridging aminocarbyne (at the back) through to the bridging vinyliminium (in the middle) to the allylidene complex (in the front). The complexes are the result of subsequent additions of alkynes and acetylides that take place at the bridging unit. For each step, the bridging coordination provides activation and also regio‐ and stereocontrol of the addition reactions. Thus, the nature and conformation of the growing bridging organic frame can be largely predicted and properly designed. Details are discussed in the article by V. Zanotti et al. on p. 1799 ff.
Women with Saethre‐Chotzen syndrome are at increased risk of breast cancer
Authors: Sahlin Pelle , Windh Per , Lauritzen Claes , Emanuelsson Monica , Grönberg Henrik , Stenman Göran 
Published: April 2007

AbstractThe Saethre‐Chotzen syndrome is an autosomal, dominantly inherited craniosynostosis caused by mutations in the basic helix‐loop‐helix transcription factor gene TWIST1. This syndrome has hitherto not been associated with an increased risk of cancer. However, recent studies, using a murine breast tumor model, have shown that Twist may act as a key regulator of metastasis and that the gene is overexpressed in subsets of sporadic human breast cancers. Here, we report a novel association between the Saethre‐Chotzen syndrome and breast cancer. In 15 Swedish Saethre‐Chotzen families, 15 of 29 (52%) women carriers over the age of 25 had developed breast cancer. At least four patients developed breast cancer before 40 years of age, and five between 40 and 50 years of age. The observed cases with breast cancer (n = 15) are significantly higher than expected (n = 0.89), which gives a standardized incidence ratio (SIR) of 16.80 (95% CI 1.54–32.06). Our finding of a high frequency of breast cancer in women with the Saethre‐Chotzen syndrome identifies breast cancer as an important and previously unrecognized symptom characteristic of this syndrome. The results strongly suggest that women carriers of this syndrome would benefit from genetic counseling and enrolment in surveillance programs including yearly mammography. Our results also indicate that the TWIST1 gene may be a novel breast cancer susceptibility gene. Additional studies are, however, necessary to reveal the mechanism by which TWIST1 may predispose to early onset breast cancer in Saethre‐Chotzen patients. © 2007 Wiley‐Liss, Inc.
One hit, two hits, three hits, more? Genomic changes in the development of retinoblastoma
Authors: Corson Timothy W. , Gallie Brenda L. 
Published: April 2007

AbstractThe childhood eye cancer retinoblastoma is initiated by the loss of both alleles of the prototypic tumor suppressor gene, RB1. However, a large number of cytogenetic and comparative genomic hybridization (CGH) studies have shown that these M1 and M2 mutational events—although necessary for initiation—are not the only genomic changes in retinoblastoma. Some of these subsequent changes, which we have termed M3 to Mn, are likely crucial for tumor progression not only in retinoblastoma but also in other cancers. Moreover, genes showing genomic change in cancer are more stable markers and, therefore, possible therapeutic targets than genes simply differentially expressed. In this review, we provide the first comprehensive summary of the genomic evidence implicating gain of 1q, 2p, 6p, and 13q, and loss of 16q in retinoblastoma oncogenesis, including karyotype, CGH, and microarray CGH data. We discuss the search for candidate oncogenes and tumor suppressor genes within these regions, including the candidates (KIF14, MDM4, MYCN, E2F3, DEK, CDH11, and others), plus associations between genomic changes and clinical parameters. We also review studies of other regions of the retinoblastoma genome, the epigenetic changes of aberrant methylation of MGMT, RASSF1A, CASP8, and MLH1, and the roles microRNAs might play in this cancer. Although many candidate genes have yet to be functionally validated in retinoblastoma, work in this field lays out a molecular cytogenetic pathway of retinoblastoma development. Candidate cancer genes carry diagnostic, prognostic, and therapeutic implications beyond retinoblastoma. © 2007 Wiley‐Liss, Inc.
Structural brain magnetic resonance imaging of pediatric twins
Authors: Giedd Jay N. , Schmitt James Eric , Neale Michael C. 
Published: April 2007

AbstractTo explore the relative impact of genetic and nongenetics factors on human brain anatomy during childhood and adolescence development, a collaborative team from the Child Psychiatry Branch of the National Institute of Mental Health and Virginia Commonwealth University is applying structural equation modeling to brain morphometric data acquired via magnetic resonance imaging from a large sample of monozygotic and dizygotic pediatric subjects. In this report, we discuss methodologic issues related to pediatric neuroimaging twin studies and synthesize results to date from the project. Current sample size from the ongoing longitudinal study is approximately 150 twin pairs. Consistent themes are: (1) heritability is high and shared environmental effects low for most brain morphometric measures; (2) the cerebellum has a distinct heritability profile; (3) genetic and environmental factors contribute to the development of the cortex in a regional and age specific manner; and (4) shared genetic effects account for more of the variance than structure specific effects. Understanding of influences on trajectories of brain development may shed light on the emergence of psychopathology during childhood and adolescence and ultimately may guide therapeutic interventions. Hum Brain Mapp 2007. © 2007 Wiley‐Liss, Inc.
Mouse behavioral mutants have neuroimaging abnormalities
Authors: Nieman Brian J. , Lerch Jason P. , Bock Nicholas A. , Chen X. Josette , Sled John G. , Henkelman R. Mark 
Published: April 2007

AbstractImpaired cognitive, memory, or motor performance is a distinguishing characteristic of neurological diseases. Although these symptoms are frequently the most evident in human patients, additional markers of disease are critical for proper diagnosis and staging. Noninvasive neuroimaging methods have become essential in this capacity and provide means of evaluating disease and tracking progression. These imaging methods are also becoming available to scientists in the research laboratory for assessment of animal models of neurological disease. Imaging in mouse models of neurological disease is of particular interest, owing to the availability of inbred strains and genetic manipulation tools that permit detailed investigation of the roles of various genes and gene products in disease pathogenesis. However, the relative prevalence of neuroimaging abnormalities in mice exhibiting neurological symptoms has not been reported. This prevalence has both theoretical and practical value because it is influenced by both the sensitivity of macroscopic anatomical measures to underlying genetic and disease processes and by the efficiency of neuroimaging in detecting and characterizing these effects. In this paper, we describe a meta‐analysis of studies involving behavioral mouse mutants at our laboratory. In summary, we have evaluated 15 different mutant genotypes, of which 13 showed abnormal neuroimaging findings. This indicates a surprisingly high prevalence of neuroimaging abnormalities (87%) and suggests that disease processes affecting behavior generally alter neuroanatomy as well. As a consequence, neuroimaging provides a highly sensitive marker of neurological disease in mice exhibiting abnormal behavior. Hum Brain Mapp 2007. © 2007 Wiley‐Liss, Inc.
Targeted delivery of doxorubicin to the rat brain at therapeutic levels using MRI‐guided focused ultrasound
Authors: Treat Lisa H. , McDannold Nathan , Vykhodtseva Natalia , Zhang Yongzhi , Tam Karen , Hynynen Kullervo 
Published: April 2007

AbstractThe clinical application of chemotherapy to brain tumors has been severely limited because antitumor agents are typically unable to penetrate an intact blood‐brain barrier (BBB). Although doxorubicin (DOX) has been named as a strong candidate for chemotherapy of the central nervous system (CNS), the BBB often prevents cytotoxic levels from being achieved. In this study, we demonstrate a noninvasive method for the targeted delivery of DOX through the BBB, such that drug levels shown to be therapeutic in human tumors are achieved in the normal rat brain. Using MRI‐guided focused ultrasound with preformed microbubbles (Optison) to locally disrupt the BBB and systemic administration of DOX, we achieved DOX concentrations of 886 ± 327 ng/g tissue in the brain with minimal tissue effects. Tissue DOX concentrations of up to 5,366 ± 659 ng/g tissue were achieved with higher Optison doses, but with more significant tissue damage. In contrast, DOX accumulation in nontargeted contralateral brain tissue remained significantly lower for all paired samples (p < 0.001). These results suggest that targeted delivery by focused ultrasound may render DOX chemotherapy a viable treatment option against CNS tumors, despite previous accessibility limitations. In addition, MRI signal enhancement in the sonicated region correlated strongly with tissue DOX concentration (r = 0.87), suggesting that contrast‐enhanced MRI could perhaps indicate drug penetration during image‐guided interventions. Our technique using MRI‐guided focused ultrasound to achieve therapeutic levels of DOX in the brain offers a large step forward in the use of chemotherapy to treat patients with CNS malignancies. © 2007 Wiley‐Liss, Inc.
Inhibition of breast tumor growth and angiogenesis by a medicinal herb: Ocimum gratissimum
Authors: Nangia‐Makker Pratima , Tait Larry , Shekhar Malathy P.V. , Palomino Eduardo , Hogan Victor , Piechocki Marie P. , Funasaka Tatsuyoshi , Raz Avraham 
Published: April 2007

AbstractOcimum sp. is a traditionally used medicinal herb, which shows anti‐oxidant, anti‐carcinogenic, radio‐protective and free radical scavenging properties. So far no detailed studies have been reported on its effects on human cancers. Thus, we analyzed its effects on human breast cancer utilizing in vitro and in vivo methodologies. Aqueous extracts were prepared from the mature leaves of Ocimum gratissimum (OG) cultivated devoid of pesticides. Tumor progression and angiogenesis related processes like chemotaxis, proliferation, apoptosis, 3D growth and morphogenesis, angiogenesis and tumor growth were studied in the presence or absence of the extract, and in some experiments a comparison was made with purified commercially available eugenol, apigenin and ursolic acid. Aqueous OG leaf extract inhibits proliferation, migration, anchorage independent growth, 3D growth and morphogenesis and induction of COX‐2 protein in breast cancer cells. A comparative analysis with eugenol, apigenin and ursolic acid showed that the inhibitory effects on chemotaxis and 3D morphogenesis of breast cancer cells were specific to OG extract. In addition, OG extracts reduced tumor size and neoangiogenesis in a MCF10 DCIS.com xenograft model of human DCIS. This is the first detailed report showing that OG leaf extract may be of value as a breast cancer preventive and therapeutic agent and might be considered as additional additive in the arsenal of components aimed at combating breast cancer progression and metastasis. © 2007 Wiley‐Liss, Inc.
Dietary patterns and risk of laryngeal cancer: An exploratory factor analysis in Uruguayan men
Authors: De Stefani Eduardo , Boffetta Paolo , Ronco Alvaro L. , Deneo‐Pellegrini Hugo , Acosta Giselle , Mendilaharsu María 
Published: April 2007

AbstractLaryngeal carcinoma is a common malignancy among Uruguayan men. A number of case–control and prospective studies have studied the role of diet in this malignancy. To our knowledge, this is the first study that has explored broad dietary patterns by factor (principal components) analysis. The results of this study retained 6 dietary patterns. Pattern 5 (drinker) was directly associated with risk of laryngeal carcinoma (OR 3.8, 95% CI 1.9–7.5), whereas the Pattern 2 (healthy) was protective (OR 0.6, 95% CI 0.3–1.2). Finally, the Pattern 6 (western) displayed a significant increase in risk of 3.2 (95% CI 1.6–6.2). Most dietary patterns were associated with supraglottic cancer, supporting a possible etiological difference between supraglottic and glottic carcinomas. This study also suggests that the analysis of dietary patterns might be a useful approach for investigating nutritional factors implicated in laryngeal carcinogenesis. © 2007 Wiley‐Liss, Inc.
Chemical synthesis and in vitro biocompatibility tests of poly (L‐lactic acid)
Authors: Jahno Vanusca Dalosto , Mendes Ribeiro Gabriela Benderóvicz , dos Santos Luís Alberto , Ligabue Rosane , Einloft Sandra , Wimmers Ferreira Maidy Rehder , Bombonato‐Prado Karina Fittipaldi 
Published: April 2007

AbstractPolylactic acid is a polymer of great technological interest, whose excellent mechanical properties, thermal plasticity, and bioresorbability render it potentially useful for environmental applications, as a biodegradable plastic and as a biocompatible material in biomedicine. This article discusses the synthesis and characterization of poly‐L‐lactic acid, obtained through two synthetic routes: direct polycondensation reactions without organic solvents, and in a supercritical medium. Tin complexes were used as catalysts in both polymerization reactions. The polymers were characterized by 1HNMR, IR, GPC, DSC, and TGA techniques. In vitro biocompatibility tests were performed with human alveolar bone osteoblasts and there were assessed cell adhesion, proliferation and viability. The poly condensation reaction proved to be an excellent synthetic route to produce PLA polymers with different molar mass. The formation of polymers from lactic acid monomer was confirmed through techniques utilized. It was observed that cell adhesion and viability was not disturbed by the presence of the polymer, although the proliferation rate was decreased when compared to control. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res 2007
Pattern of body‐wall muscle differentiation during embryonic development of Enchytraeus coronatus (Annelida: Oligochaeta; Enchytraeidae)
Authors: Bergter Annette , Paululat Achim 
Published: April 2007

AbstractThe plesiomorphic arrangement of body‐wall musculature within the annelids is still under discussion. While polychaete groups show a great variety of patterns in their somatic muscles, the musculature of soil‐living oligochaetes was thought to represent the characteristic pattern in annelids. Oligochaete body‐wall muscles consist of an outer continuous layer of circular and an inner continuous layer of longitudinal muscles, forming a closed tube. Since designs of adult body musculature are influenced by evolutionary changes, additional patterns found during embryogenesis can give further information about possible plesiomorphic features. In oligochaetes, detailed cell‐lineage analyses document the origin of the mesoderm and consequently the muscles, but later processes of muscle formation remain unclear. In the present work, body‐wall muscle differentiation was monitored during embryogenesis of thesoil‐living oligochaete Enchytraeus coronatus (Annelida) by phalloidin staining. Primary circular muscles form in a discrete anterior‐to‐posterior segmental pattern, whereas emerging longitudinal muscles are restricted to one ventral and one dorsal pair of primary strands, which continuously elongate towards posterior. These primary muscles establish an initial muscle‐template. Secondary circular and longitudinal muscles subsequently differentiate in the previous spaces later in development. The prominent ventral primary longitudinal muscle strands on both sides eventually meet at the ventral midline due to neurulation, which moves the ventral nerve cord into a coelomic position, closing the muscle layers into a complete tube. This early embryonic pattern in E. coronatus resembles the adult body‐wall muscle arrangements in several polychaete groups as well as muscle differentiation during embryonic development of the polychaete Capitella sp. I. J. Morphol., 2007. © 2007 Wiley‐Liss, Inc.
Reappraisal of patterns of nonmarine cryptodiran turtle carotid circulation: Evidence from osteological correlates and soft tissues
Authors: Jamniczky Heather A. , Russell Anthony P. 
Published: April 2007

AbstractThe turtle cranial circulation has been employed as an important source of phylogenetic information, but recent conflicting hypotheses of relationship within Testudinata suggest reevaluation of the utility of characters drawn from this complex. As a component ofa comprehensive character analysis, the osteological correlatesof the nonmarine cryptodiran turtle carotid circulation are herein subjected to high‐resolution X‐ray computed tomography, reassessed, and statistically investigated. Three different patterns of osteological correlates, indicating three disparate cranial circulatory patterns, are described, and this finding is corroborated by evidence from circulatory soft tissues. Members of the Trionychia and Kinosternoidea exhibit patterns that differ from the more widespread condition found in testudinoid taxa. This result differs from previous work, which has indicated the presence of only two major cranial circulatory patterns, and suggests that while cranial circulatory features may be phylogenetically informative, the information contained within them indicates patterns of relationship different from those previously hypothesized. J. Morphol., 2007. © 2007 Wiley‐Liss, Inc.
Developmental strategy of the endoparasite Xenos vesparum (strepsiptera, Insecta): Host invasion and elusion of its defense reactions
Authors: Manfredini Fabio , Giusti Fabiola , Beani Laura , Dallai Romano 
Published: April 2007

AbstractTo successfully complete its endoparasitic development, the strepsipteran Xenos vesparum needs to elude the defense mechanisms of its host, the wasp Polistes dominulus. SEM and TEM observations after artificial infections allow us to outline the steps of this intimate host–parasite association. Triungulins, the mobile 1st instar larvae of this parasite, are able to “softly” overcome structural barriers of the larval wasp (cuticle and epidermis) without any traumatic reaction at the entry site, to reach the hemocoel where they settle. The parasite molts 48 h later to a 2nd instar larva, which moves away from the 1st instar exuvium, molts twice more without ecdysis (a feature unique to Strepsiptera) and pupates, if male, or develops into a neotenic female. Host encapsulation involves the abandoned 1st larval exuvium, but not the living parasite. In contrast to the usual process of encapsulation, it occurs only 48 h after host invasion or later, and without any melanization. In further experiments, first, we verified Xenos vesparum's ability to reinfect an already parasitized wasp larva. Second, 2nd instar larvae implanted in a new host did not evoke any response by hemocytes. Third, we tested the efficiency of host defense mechanisms by implanting nylon filaments in control larval wasps, excluding any effect due the dynamic behavior of a living parasite; within a few minutes, we observed the beginning of a typical melanotic encapsulation plus an initial melanization in the wound site. We conclude that the immune response of the wasp is manipulated by the parasite, which is able to delay and redirect encapsulation towards a pseudo‐target, the exuvia of triungulins, and to elude hemocyte attack through an active suppression of the immune defense and/or a passive avoidance of encapsulation by peculiar surface chemical properties. J. Morphol., 2007 © 2007 Wiley‐Liss, Inc.