bluuebunny/crossref_metadata_2025_split huggingface dataset:
Focal adhesion signaling is required for myometrial ERK activation and contractile phenotype switch before labor
Authors: Li Yunping , Gallant Cynthia , Malek Sabah , Morgan Kathleen G. 
Published: August 2006

AbstractIn late pregnancy rapidly increasing fetal growth dramatically increases uterine wall tension. This process has been implicated in the activation of the myometrium for labor, but the mechanisms involved are unclear. Here, we tested, using a rat model, the hypothesis that gestation‐dependent stretch, via activation of focal adhesion signaling, contributes to the published activation of myometrial ERK at the end of pregnancy. Consistent with this hypothesis, we show here that ERK is targeted to adhesion plaques during late pregnancy. Furthermore, myometrial stretch triggers a dramatic increase in myometrial contractility and ERK and caldesmon phosphorylation, confirming the presence of stretch sensitive myometrial signaling element. Screening by anti‐phosphotyrosine immunoblotting for focal adhesion signaling in response to stretch reveals a significant increase in the tyrosine phosphorylated bands identified as focal adhesion kinase (FAK), A‐Raf, paxillin, and Src. Pretreatment with PP2, a Src inhibitor, significantly suppresses the stretch‐induced increases in FAK, paxillin, Src, ERK and caldesmon phosphorylation and myometrial contractility. Thus, focal adhesion‐Src signaling contributes to ERK activation and promotes contraction in late pregnancy. These results point to focal adhesion signaling molecules as potential targets in the modulation of the myometrial contractility and the onset of labor. J. Cell. Biochem. 100: 129–140, 2007. © 2006 Wiley‐Liss, Inc.
Twist negatively regulates osteoblastic differentiation in human periodontal ligament cells
Authors: Komaki Motohiro , Karakida Takeo , Abe Mayumi , Oida Shinichiro , Mimori Kaori , Iwasaki Kengo , Noguchi Kazuyuki , Oda Shigeru , Ishikawa Isao 
Published: August 2006

AbstractPeriodontal ligament (PDL) is a thin fibrous connective tissue located between two mineralized tissues, alveolar bone and cementum, which maintains a constant width physiologically. The mechanisms by which PDL resists mineralization are not well understood. Twist is a basic helix loop helix protein that plays a central role in regulation of early osteogenesis. We investigated the localization of Twist in PDL and compared the expression of Twist and osteoblast‐related genes in PDL cells with those in osteoblast‐like cells in the presence or absence of recombinant human bone morphogenetic protein (BMP)‐2. Histochemical analysis showed that Twist was expressed along alveolar bone surface in PDL. PDL cells constitutively expressed Twist gene and the expression level was higher than that in osteoblast‐like cells. In osteoblast‐like cell culture, BMP‐2 enhanced osteoblast‐related gene expression, while Twist expression was slightly decreased. In contrast, BMP‐2 increased runt‐related transcription factor (Runx)‐2, but failed to enhance alkaline phosphatase (ALP) and osteocalcin (OCN) gene expression in PDL cells. Interestingly, unlike in osteoblast‐like cells, Twist expression was upregulated by BMP‐2 in PDL cells. We transiently knocked down Twist gene in PDL cells using a short interference RNA expression vector (siTwist) and found that ALP, osteopontin (OPN), bone sialoprotein (BSP) genes expression and basal level of ALP activity were slightly increased, whereas Runx2 and OCN genes were not affected. Collectively, these results suggest that Twist may act as a negative regulator of osteoblastic differentiation in PDL cells. J. Cell. Biochem. 100: 303–314, 2007. © 2006 Wiley‐Liss, Inc.
Regulation of Sprouty2 stability by mammalian Seven‐in‐Absentia homolog 2
Authors: Nadeau Robert J. , Toher Jessica L. , Yang Xuehui , Kovalenko Dmitry , Friesel Robert 
Published: August 2006

AbstractMammalian Sprouty (Spry) gene expression is rapidly induced upon activation of the FGF receptor signaling pathway in multiple cell types including cells of mesenchymal and epithelial origin. Spry2 inhibits FGF‐dependent ERK activation and thus Spry acts as a feedback inhibitor of FGF‐mediated proliferation. In addition, Spry2 interacts with the ring‐finger‐containing E3 ubiquitin ligase, c‐Cbl, in a manner that is dependent upon phosphorylation of Tyr55 of Spry2. This interaction results in the poly‐ubiquitination and subsequent degradation of Spry2 by the proteasome. Here, we describe the identification of another E3 ubiquitin ligase, human Seven‐in‐Absentia homolog‐2 (SIAH2), as a Spry2 interacting protein. We show by yeast two‐hybrid analysis that the N‐terminal domain of Spry2 and the ring finger domain of SIAH2 mediated this interaction. Co‐expression of SIAH2 resulted in proteasomal degradation of Spry1, 2, and to a lesser extent Spry4. The related E3 ubiquitin‐ligase, SIAH1, had little effect on Spry2 protein stability when co‐expressed. Unlike c‐Cbl‐mediated degradation of Spry2, SIAH2‐mediated degradation was independent of phosphorylation of Spry2 on Tyr55. Spry2 was also phosphorylated on Tyr227, and phosphorylation of this residue was also dispensable for SIAH2‐mediated degradation of Spry2. Finally, co‐expression of SIAH2 with Spry2 resulted in a rescue of FGF2‐mediated ERK phosphorylation. These data suggest a novel mechanism whereby Spry2 stability is regulated in a manner that is independent of tyrosine phosphorylation, and provides an addition level of control of Spry2 protein levels. J. Cell. Biochem. 100: 151–160, 2007. © 2006 Wiley‐Liss, Inc.
TGFβ inducible early gene‐1 (TIEG1) and cardiac hypertrophy: Discovery and characterization of a novel signaling pathway
Authors: Rajamannan Nalini M. , Subramaniam Malayannan , Abraham Theodore P. , Vasile Vlad C. , Ackerman Michael J. , Monroe David G. , Chew Teng‐Leong , Spelsberg Thomas C. 
Published: August 2006

AbstractCellular mechanisms causing cardiac hypertrophy are currently under intense investigation. We report a novel finding in the TGFβ inducible early gene (TIEG) null mouse implicating TIEG1 in cardiac hypertrophy. The TIEG−/− knock‐out mouse was studied. Male mice age 4–16 months were characterized (N = 86 total) using echocardiography, transcript profiling by gene microarray, and immunohistochemistry localized upregulated genes for determination of cellular mechanism. The female mice (N = 40) did not develop hypertrophy or fibrosis. The TIEG−/− knock‐out mouse developed features of cardiac hypertrophy including asymmetric septal hypertrophy, an increase in ventricular size at age 16 months, an increase (214%) in mouse heart/weight body weight ratio TIEG−/−, and an increase in wall thickness in TIEG−/− mice of (1.85 ± 0.21 mm), compared to the control (1.13 ± 0.15 mm, P < 0.04). Masson Trichrome staining demonstrated evidence of myocyte disarray and myofibroblast fibrosis. Microarray analysis of the left ventricles demonstrated that TIEG−/− heart tissues expressed a 13.81‐fold increase in pituitary tumor‐transforming gene‐1 (Pttg1). An increase in Pttg1 and histone H3 protein levels were confirmed in the TIEG−/− mice hearts tissues. We present evidence implicating TIEG and possibly its target gene, Pttg1, in the development of cardiac hypertrophy in the TIEG null mouse. J. Cell. Biochem. 100: 315–325, 2007. © 2006 Wiley‐Liss, Inc.
Functional analysis of survivin in spindle assembly in Xenopus egg extracts
Authors: Canovas Pedro M. , Guadagno Thomas M. 
Published: August 2006

AbstractSurvivin is a member of the inhibitor of apoptosis (IAP) protein family that serves critical roles in mitosis and cytokinesis. Many studies have suggested Survivin's involvement in spindle regulation, but direct biochemical evidence for this has been lacking. Using the cell‐free system of Xenopus egg extracts, we tested whether Survivin was necessary for the assembly of metaphase spindles. Removal or inhibition of Xenopus Survivin causes the disruption in the formation of metaphase spindles. In particular, we observe the generation of microtubule (MT) asters or poorly formed shortened spindle structures. In the latter phenotype the spindle structures display a decrease pole‐to‐pole length and a reduction of MTs around the chromatin indicating that Survivin may promote the stabilization of MT–chromatin interactions. In addition, function analysis of Survivin's conserved phosphorylation site Thr34 (Thr43 in Xenopus) and tubulin‐binding domain was also assessed in regulating spindle assembly. Treatment of Xenopus egg extracts with a recombinant Survivin mutant that contained an alanine residue substitution at Thr43 (SURT43A mutant) or that was missing the C‐terminal tubulin‐binding domain (SURCL mutant) produced an increased frequency of MT asters and shorten abnormal spindle structures in Xenopus egg extracts. Interestingly, a phosphomimetic mutation made at residue Thr43 of Survivin (SURT43E mutant) generated a high frequency of MT asters implying that premature ‘activation’ of Survivin may interfere with an early stage of spindle assembly. Taken together, we propose that Survivin is a necessary component of the mitotic spindle and its phosphorylation at residue Thr43 is important for Survivin function in spindle assembly. J. Cell. Biochem. 100: 217–229, 2007. © 2006 Wiley‐Liss, Inc.
Extreme sensitivity to Yondelis® (Trabectedin, ET‐743) in low passaged sarcoma cell lines correlates with mutated p53
Authors: Moneo Victoria , Serelde Beatriz G. , Fominaya Jesús , Leal Juan F.M. , Blanco‐Aparicio Carmen , Romero Lourdes , Sánchez‐Beato Margarita , Cigudosa Juan C. , Tercero Juan C. , Piris Miguel A. , Jimeno Jose , Carnero Amancio 
Published: August 2006

AbstractYondelis® (Trabectedin, ET‐743) is a marine anticancer agent currently in Phase II/III development in patients with advanced pretreated soft tissue sarcoma. In the present study, we generated a panel of low passaged tumor cell lines from samples explanted from chemonaive sarcoma patients with different tumor types. We assessed in vitro sensitivity/resistance to Trabectedin and doxorubicin in a panel of sarcoma cell lines and examined the correlation between molecular alterations in DNA repair genes and sensitivity to Trabectedin. We treated cell lines with Trabectedin and doxorubicin in both 96‐h and clonogenic assays. In both assays, well‐defined groups of resistant and sensitive cell lines were observed. Resistance to Trabectedin did not correlate with resistance to doxorubicin, indicating that the two drugs may have different mechanisms of resistance. p53 mutations and deletions correlated with extreme sensitivity (IC50 < 1 nM) to Trabectedin (P < 0.01). In a pair of isogenic cell lines differing only in the presence or absence of wild‐type p53, the absence of p53 rendered cells threefold more sensitive to Trabectedin. J. Cell. Biochem. 100: 339–348, 2007. © 2006 Wiley‐Liss, Inc.
Interleukin‐1β and tetradecanoylphorbol acetate‐induced biosynthesis of tumor necrosis factor α in human hepatoma cells involves the transcription factors ATF2 and c‐Jun and stress‐activated protein kinases
Authors: Bauer Inge , Al Sarraj Jude , Vinson Charles , Larsen Reinhard , Thiel Gerald 
Published: August 2006

AbstractThe proinflammatory cytokine tumor necrosis factor (TNF) α is mainly produced in cells from the monocyte/macrophage lineage. TNFα is also a key signaling molecule in the liver functioning as an important physiological and pathogenic mediator. In hepatocytes or human hepatoma cells TNFα is expressed at extremely low levels but TNFα biosynthesis can be induced by interleukin (IL)‐1β or 12‐O‐tetradecanoylphorbol‐13‐acetate (TPA). Here, we show that IL‐1β and TPA stimulated TNFα gene transcription in hepatoma cells mediated by a composite TPA‐responsive element/cAMP response element. Both IL‐1β and TPA triggered phosphorylation and activation of the basic region leucine zipper transcription factors c‐Jun and ATF2 and expression of dominant‐negative mutants of c‐Jun and ATF2‐reduced TNFα promoter activity and secretion of TNFα. Expression of the nuclear dual‐specific MAP kinase phosphatase‐1 (MKP‐1) blocked TNFα promoter activity and TNFα secretion following IL‐1β or TPA stimulation, indicating that MKP‐1 functions as a nuclear shut‐of‐device of IL‐1β and TPA‐induced TNFα expression. J. Cell. Biochem. 100: 242–255, 2007. © 2006 Wiley‐Liss, Inc.
Germinal vesicle chromatin configurations of bovine oocytes
Authors: Liu Yong , Sui Hong‐Shu , Wang Hui‐Li , Yuan Ji‐Hong , Luo Ming‐Jiu , Xia Ping , Tan Jing‐He 
Published: August 2006

AbstractA common feature in the configuration of germinal vesicle (GV) chromatin in most species is that diffuse chromatin condenses into a perinucleolar ring during follicular growth; however, no such ring was observed in goat oocytes. Reports on whether bovine GV chromatin condenses into a perinucleolar ring are controversial. Besides, it is not known whether the perinucleolar ring in an oocyte represents a step toward final maturation or atresia. Changes in GV chromatin configurations during growth and maturation of bovine oocytes were studied using a new method that allows a clearer visualization of both the nucleolus and the chromatin after Hoechst and chromomycin A3staining. On the basis of the degree of condensation and distribution, the GV chromatin of bovine oocytes were classified into five configurations: NSN with diffuse chromatin in the whole nuclear area, N with condensed netlike chromatin, C with clumped chromatin, SN with clumped chromatin surrounding the nucleoli, and F with floccular chromatin near the nucleoli and near the nuclear envelope. Most of the oocytes were at the NSN stage in the <1.4‐mm follicles, but the NSN pattern disappeared completely in follicles larger than 1.5mm. The SN pattern began to emerge in 1.5‐mm follicles, and the number of SN oocytes increased while the number of oocytes with N and C configurations decreased with follicular growth. During maturation in vivo, while the number of N, C, and SN oocytes decreased, that of the F oocytes increased and reached maximum at 51h post prostaglandin injection. After that, the number of F oocytes decreased significantly because of germinal vesicle breakdown (GVBD). During maturation in vitro, GV chromatin configurations changed in a similar manner as during maturation in vivo. Fewer oocytes were at N, C, and SN stages, but more were at F and GVBD stages in the atretic than in the healthy follicles. Serum starvation slowed the F‐GVBD transition of the in vitro maturing oocytes. More oocytes were of the SN or C configuration when ovaries were transported at 45–40°C than at 35–30°C. Most of the heated oocytes were blocked at the SN stage during in vitro maturation. It is concluded that (i) bovine GV chromatin condenses into a perinucleolar ring during follicular growth; (ii) bovine oocytes were synchronized at the F stage before GVBD; (iii) oocyte GV chromatin configurations were affected by serum starvation, high temperature, and follicular atresia. Microsc. Res. Tech., 2006. © 2006 Wiley‐Liss, Inc.
Atomic force microscopy characterization of Xenopus laevis oocyte plasma membrane
Authors: Orsini F. , Santacroce M. , Perego C. , Lenardi C. , Castagna M. , Mari S.A. , Sacchi V.F. , Poletti G. 
Published: August 2006

AbstractWe used atomic force microscopy (AFM) to characterize the plasma membrane of Xenopus laevis oocytes. The samples were prepared according to novel protocols, which allowed the investigation of the extra‐ and intracellular sides of the membrane, both of which showed sparsely distributed spherical‐like protrusions. Regions with comparably sized and densely packed structures arranged in an orderly manner were visualized and dimensionally characterized. In particular, two different arrangements, hexagonal and square packing, were recognizable in ordered regions. The lateral dimension of structures visualized on the external side had a normal distribution centered on 25.5 ± 0.3 nm (mean value ± SE), whereas that on the intracellular side showed a normal distribution centered on 30.2 ± 0.8 nm. The height of the protrusions was 2–5 nm on the external side and 1–3 nm on the intracellular side. The mean number of structures on the external and intracellular sides of the plasma membrane was about 1000 μm−2 and 850 μm−2 respectively. Trypsin treatment greatly decreased the size of the membrane protrusions, thus confirming the proteic nature of the structures. These results show that AFM is a useful tool for structural characterization of proteins in a native eukaryotic membrane. Microsc. Res. Tech., 2006. © 2006 Wiley‐Liss, Inc.
Sensilla and secretory glands in the antennae of a primitive ant: Dinoponera lucida (Formicidae: Ponerinae)
Authors: Marques‐Silva Solange , Matiello‐Guss Cirlei P. , Delabie Jacques H.C. , Mariano Cléa S.F. , Zanuncio José C. , Serrão José Eduardo 
Published: August 2006

AbstractMorphology of the antennae of the female workers of the ponerine ant Dinoponera lucida was examined by light and scanning electron microscopy. In several antennomers, we found secretory gland cells of class I and III. Class III gland cells release their secretion through single pores in the antennal surface, whereas class I secretory cells are seen as tall epidermal cells close to the cuticle. Both gland types have weak reaction for total proteins and neutral polysaccharides. Six distinct sensilla types were observed: trichodea, chaetica, campaniform, basiconica, placodea, and coeloconica. The possible sensory functions of these sensilla and the gland functions are discussed. Microsc. Res. Tech., 2006. © 2006 Wiley‐Liss, Inc.
Evaluation of a femtosecond fiber laser for two‐photon fluorescence correlation spectroscopy
Authors: Unruh Jay R. , Price E. Shane , Molla Roque G. , Hui Rongqing , Johnson Carey K. 
Published: August 2006

AbstractThis work evaluates a femtosecond fiber laser for use in two‐photon fluorescence fluctuation spectroscopy. Fiber lasers present an attractive alternative to Ti:Sapphire systems because of their compact size and portability. Autocorrelation of the second harmonic generation signal from the laser demonstrates that its stability is sufficient for two‐photon fluorescence correlation spectroscopy. Fluorescence correlation spectroscopy autocorrelation traces were well fit by a Gaussian–Lorentzian squared model with a beam waist near the diffraction limit for the 810 nm wavelength. A photon counting histogram collected with this system also fit nicely to a single‐species model, further demonstrating the quality of the focal shape. The authors conclude that the output from the femtosecond fiber laser is sufficiently stable and has a high enough quality beam shape for fluctuation fluorescence methods, and thus represents an effective, compact, readily portable two‐photon excitation source. Microsc. Res. Tech., 2006. © 2006 Wiley‐Liss, Inc.
Adult celiac disease: What is the role of MRI?
Authors: Tomei Ernesto , Semelka Richard C. , Braga Larissa , Laghi Andrea , Paolantonio Pasquale , Marini Mario , Passariello Roberto , Di Tola Marco , Sabbatella Luigi , Picarelli Antonio 
Published: August 2006

AbstractPurposeTo evaluate the ability of MRI to identify intra‐ and extraintestinal findings of celiac disease in an adult population.Materials and MethodsForty‐one subjects (18 men and 23 women; mean age = 41.3 years; 31 with biopsy‐proven celiac disease, and 10 healthy volunteers) underwent MRI of the small bowel. MR studies were performed on a 1.5‐T magnet using T2‐weighted half‐Fourier single‐shot turbo spin‐echo (HASTE) and true fast imaging in steady‐state precession (True‐FISP) sequences. The MR features and sensitivity, and the specificity and accuracy of some of these features are described.ResultsIn the 31 celiac patients, MRI showed bowel dilatation in 61.3% (N = 19), increased number of ileal folds in 48.4% (N = 15), reversed fold pattern abnormality in 38.7% (N = 12), increased wall thickness in 16.1% (N = 5), duodenal stenosis in 6.5% (N = 2), intussusception in 12.9% (N = 4), mesenteric lymphadenopathy in 41.9% (N = 13), mesenteric vascular changes in 22.6% (N = 7), ascites in 6.5% (N = 2), and no abnormalities in 12.9% (N = 4). The volunteers had unremarkable exams. The overall specificity and accuracy were 100%, and sensitivity was 79% and 75% for increased number of ileal folders and reversed fold pattern abnormality, respectively.ConclusionMRI is able to demonstrate intra‐ and extraintestinal features that may lead to the diagnosis of celiac disease in adults. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Emerging techniques: Whole‐body screening and staging with MRI
Authors: Lauenstein Thomas C. , Semelka Richard C. 
Published: August 2006

AbstractStrategies for screening or tumor staging include various modalities such as plain radiography, computed tomography (CT), MRI, and ultrasound. Technical innovations have created the feasibility to use MRI to image the entire body in a relatively short time‐period. Whole‐body MRI may play a potentially important role in evaluating for cancer or vascular disease. This article describes the rationale for using MRI to display the entire body, the techniques employed in whole‐body MRI, possibilities and limitations, and summarizes first clinical results for screening and staging purposes. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Quantitative measurements of regional lung ventilation using helium‐3 MRI in a methacholine‐induced bronchoconstriction model
Authors: Mosbah Karim , Crémillieux Yannick , Adeleine Patrice , Dupuich David , Stupar Vasile , Nemoz Chantal , Canet Emmanuelle , Berthezène Yves 
Published: August 2006

AbstractPurposeTo demonstrate ventilation changes in an animal model of methacholine‐induced bronchoconstriction using hyperpolarized (HP) helium‐3 (He‐3) MRI.Materials and MethodsBronchoconstriction was induced in 11 healthy rats using an intravenous injection of methacholine. The He‐3 was laser‐polarized using a custom‐built system. MRI studies were performed on a 2‐Tesla bore magnet. Coronal dynamic ventilation images were obtained using a single inhalation of the laser‐polarized He‐3 gas before and after methacholine injection. Ventilation image series were processed on a pixel‐by‐pixel basis to generate three regional ventilation parameters: gas flow rate, filling time, and maximum gas volume. Student's paired t‐test was used for analysis.ResultsVentilation image series with a temporal resolution of 5 msec were obtained before and after methacholine challenge. Quantitative regional gas dynamic information demonstrated statistically significant differences between the baseline and constricted states. Following methacholine injection, the mean flow values were significantly lower for the right lung (RL) (P = 0.006) and left lung (LL) (P = 0.024), while the mean filling time was found to be greater (RL: P = 0.08, LL: P = 0.021). Gas volume values at maximum inspiration were found to be significantly lower after methacholine (RL: P = 0.002; LL: P = 0.036).ConclusionHe‐3 MRI demonstrated and quantified regional ventilation changes in bronchoconstriction conditions in rats. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.