bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tenascin‐R and axon growth‐promoting molecules are up‐regulated in the regenerating visual pathway of the lizard (Gallotia galloti)
Authors: Lang Dirk M. , Monzon‐Mayor Maximina , del Mar Romero‐Aleman Maria , Yanes Carmen , Santos Elena , Pesheva Penka 
Published: March 2008

AbstractIt is currently unclear whether retinal ganglion cell (RGC) axon regeneration depends on down‐regulation of axon growth‐inhibitory proteins, and to what extent outgrowth‐promoting substrates contribute to RGC axon regeneration in reptiles. We performed an immunohistochemical study of the regulation of the axon growth‐inhibiting extracellular matrix molecules tenascin‐R and chondroitin sulphate proteoglycan (CSPG), the axon outgrowth‐promoting extracellular matrix proteins fibronectin and laminin, and the axonal tenascin‐R receptor protein F3/contactin during RGC axon regeneration in the lizard, Gallotia galloti. Tenascin‐R and CSPG were expressed in an extracellular matrix‐, oligodendrocyte/myelin‐ and neuron‐associated pattern and up‐regulated in the regenerating optic pathway. The expression pattern of tenascin‐R was not indicative of a role in channeling or restriction of re‐growing RGC axons. Up‐regulation of fibronectin, laminin, and F3/contactin occurred in spatiotemporal patterns corresponding to tenascin‐R expression. Moreover, we analyzed the influence of substrates containing tenascin‐R, fibronectin, and laminin on outgrowth of regenerating lizard RGC axons. In vitro regeneration of RGC axons was not inhibited by tenascin‐R, and further improved on mixed substrates containing tenascin‐R together with fibronectin or laminin. These results indicate that RGC axon regeneration in Gallotia galloti does not require down‐regulation of tenascin‐R or CSPG. Presence of tenascin‐R is insufficient to prevent RGC axon growth, and concomitant up‐regulation of axon growth‐promoting molecules like fibronectin and laminin may override the effects of neurite growth inhibitors on RGC axon regeneration. Up‐regulation of contactin in RGCs suggests that tenascin‐R may have an instructive function during axon regeneration in the lizard optic pathway. © 2008 Wiley Periodicals, Inc. Develop Neurobiol, 2008
Pseudoaneurysm of the breast after blunt trauma: Successful treatment with ultrasound‐guided compression
Authors: Al Hadidy Azmy M. , Al Najar Mahasen S. , Farah Ghassan R. , Tarawneh Emad S. 
Published: March 2008

AbstractWe present a case of breast pseudoaneurysm following a blunt trauma in a 58‐year‐old woman. Few cases of breast pseudoaneurysm have been reported in the literature, and most of these are related to previous interventional procedures. Pseudoaneurysm was suspected on real‐time sonography and confirmed with color Doppler and spectral wave analysis, which revealed a characteristic to‐and‐fro pattern. Unlike previously reported cases, treatmentwith ultrasound‐guided compression was successful. © 2008 Wiley Periodicals, Inc. J Clin Ultrasound, 2008.
Reconstruction of corneal epithelium with cryopreserved corneal limbal stem cells in a goat model
Authors: Mi Shengli , Yang Xueyi , Zhao Qingmei , Qu Lei , Chen Shuming , M. Meek Keith , Dou Zhongying 
Published: March 2008

AbstractWe describe a procedure to construct an artificial corneal epithelium from cryopreserved limbal stem cells (LSCs) for corneal transplantation. The LSCs were separated from limbal tissue of male goats. The primary LSCs were identified by flow cytometry and were expanded. They were examined for stem cell‐relevant properties and cryopreserved in liquid nitrogen. Cryopreserved LSCs were thawed and then transplanted onto human amniotic membrane, framed on a nitrocellulose sheet, to construct corneal epithelium sheets. The artificial corneal epithelium was transplanted into the right eye of pathological models of total limbal stem cell deficiency (LSCD). Then, the effects of reconstruction were evaluated by clinical observation and histological examination. Polymerase chain reaction analysis was used to detect the SRY gene. The data showed that transplantation of cryopreserved LSCs, like fresh LSCs, successfully reconstructed damaged goat corneal surface gradually, but the SRY gene expression from male goat cells could only be detected in the first 2 months after transplantation. The therapeutic effect of the transplantation may be associated with the inhibition of inflammation‐related angiogenesis after transplantation of cryopreserved LSCs. This study provides the first line of evidence that cryopreserved LSCs can be used for reconstruction of damaged corneas, presenting a remarkable potential source for transplantation in the treatment of corneal disorders. Mol. Reprod. Dev. 75: 1607–1616, 2008. © 2008 Wiley‐Liss, Inc.
Integration of CREB and bHLH transcriptional signaling pathways through direct heterodimerization of the proteins: Role in muscle and testis development
Authors: Muir Tera , Wilson‐Rawls Jeanne , Stevens Jeffrey D. , Rawls Alan , Schweitzer Ronen , Kang ChulHee , Skinner Michael K. 
Published: March 2008

AbstractThe cAMP response element binding protein/activating transcription factor (CREB/ATF) family of transcription factors is hormone responsive and critical for nearly all mammalian cell types. The basic helix‐loop‐helix (bHLH) family of transcription factors is important during the development and differentiation of a wide variety of cell types. Independent studies of the role of the bHLH protein scleraxis in testicular Sertoli cells and paraxis in muscle development using yeast‐2‐hybrid screens provided the novel observation that bHLH proteins can directly interact with ATF/CREB family members. Analysis of the interactions demonstrated the helix‐loop‐helix domain of bHLH proteins directly interacts with the leucine zipper (ZIP) region of CREB2/ATF4 to form heterodimers. The direct bHLH–CREB2 binding interactions were supported using co‐immunoprecipitation of recombinant proteins. Structural analysis of bHLH and ATF4 heterodimer using previous crystal structures demonstrated the heterodimer likely involves the HLH and Zip domains and has the potential capacity to bind DNA. Transfection assays demonstrated CREB2/ATF4 over‐expression blocked stimulatory actions of scleraxis or paraxis. CREB1 inhibited MyoD induced myogenic conversion of C3H10T1/2 cells. CREB2/ATF4 and scleraxis are expressed throughout embryonic and postnatal testis development, with scleraxis specifically expressed in Sertoli cells. ATF4 and scleraxis null mutant mice both had similar adult testis phenotypes of reduced spermatogenic capacity. In summary, bHLH and CREB family members were found to directly heterodimerize and inhibit the actions of bHLH dimers on Sertoli cells and myogenic precursor cells. The observations suggest a mechanism for direct cross‐talk between cAMP induced and bHLH controlled cellular differentiation. Mol. Reprod. Dev. 75: 1637–1652, 2008. © 2008 Wiley‐Liss, Inc.
Cyclin B synthesis and rapamycin‐sensitive regulation of protein synthesis during starfish oocyte meiotic divisions
Authors: Lapasset Laure , Pradet‐Balade Bérengère , Vergé Valérie , Lozano Jean‐Claude , Oulhen Nathalie , Cormier Patrick , Peaucellier Gérard 
Published: March 2008

AbstractTranslation of cyclin mRNAs represents an important event for proper meiotic maturation and post‐fertilization mitoses in many species. Translational control of cyclin B mRNA has been described to be achieved through two separate but related mechanisms: translational repression and polyadenylation. In this paper, we evaluated the contribution of global translational regulation by the cap‐dependent translation repressor 4E‐BP (eukaryotic initiation factor 4E‐binding protein) on the cyclin B protein synthesis during meiotic maturation of the starfish oocytes. We used the immunosupressant drug rapamycin, a strong inhibitor of cap‐dependent translation, to check for the involvement of this protein synthesis during this physiological process. Rapamycin was found to prevent dissociation of 4E‐BP from the initiation factor eIF4E and to suppress correlatively a burst of global protein synthesis occurring at the G2/M transition. The drug had no effect on first meiotic division but defects in meiotic spindle formation prevented second polar body emission, demonstrating that a rapamycin‐sensitive pathway is involved in this mechanism. While rapamycin affected the global protein synthesis, the drug did not alter neither the specific translation of cyclin B mRNA nor the expression of the Mos protein. The expression of these two proteins was correlated with the phosphorylation and the dissociation of the cytoplasmic polyadenylation element‐binding protein from eIF4E. Mol. Reprod. Dev. 75: 1617–1626, 2008. © 2008 Wiley‐Liss, Inc.
Degree of conversion and mechanical properties studies of UDMA based materials for producing dental posts
Authors: Du Minhui , Zheng Ying 
Published: March 2008

AbstractNanocomposites are a relatively new material in producing fiber re‐enforced dental posts. The mechanical properties of nanocomposites, which strongly associate with the resin matrix, nanoparticles, and the interface between inorganic fillers and organic matrix, play an important role in determining the quality of dental posts. This work was to investigate the effect of degree of conversion (DC) and silanization of fillers on the mechanical properties of nanocomposties. Experimental Urethane dimethacrylate (UDMA) based dental composites containing unsilanized and silanized SiO2 filler and various amount of triethylene glycol dimethacrylate (TEGDMA) were prepared at the first step. The DC of composites at different ratios of UDMA/TEGDMA, cure temperature and cure time was measured by Fourier transform infrared spectroscopy. The results showed that DC increases with the increase of TEGDMA content in resin matrix. Both increase of the cure temperature and cure time can cause the increase of DC. The incorporation of fillers, either silanized, or unsilanized filler, caused the decrease of DC. However, composites reinforced with silanized silica showed relatively lower DC, and DC decreased with the increase of silanized filler content. The effect of incorporation of fillers on the mechanical properties was investigated. Silanized silica can effectively improved the flexural strength and flexural modulus of material, and these properties increased with the increase of silica content. Thermomechanical analysis (DMA) provided the similar results to the static property measurements. SEM images of fracture surfaces of specimens from flexural testing revealed the surface morphology is strongly related to the quality of interface between inorganic fillers and organic matrix. POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers
Modeling of three‐dimensional flow and heat transfer in polystyrene foam extrusion dies
Authors: Choudhary Manoj K. , Kulkarni Jaydeep A. 
Published: March 2008

AbstractA three‐dimensional mathematical model was developed to investigate the nonisothermal, non‐Newtonian polymer flow through the dies used in the polystyrene foam extrusion process. The model, based on the computational fluid dynamics (CFD) code, Polyflow, allowed for the shear rate and temperature dependence of the shear viscosity of the blowing agent laden polystyrene melt. The model also accounted for viscous heating. The shear viscosity of the polystyrene‐blowing agent mixture was measured experimentally at several temperatures. The model was used to calculate pressure, flow, and temperature distributions in two different dies used for industrial‐scale extrusion of polystyrene foams. The article presents a selection of computed results to illustrate the effect of die design on uniformity of flow at the die exit, the overall pressure drop in the die, relative magnitudes of pressure drop in the land section versus the rest of the die, and temperature distribution in the die. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers.
2‐[(Diphenylphosphino)methyl]pyridine as ligand for iron‐based atom transfer radical polymerization
Authors: Xue Zhigang , Noh Seok Kyun , Lyoo Won Seok 
Published: March 2008

Abstract2‐[(Diphenylphosphino)methyl]pyridine (DPPMP) was successfully used as a bidentate ligand in the iron‐mediated atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA) with various initiators and solvents. The effect of the catalytic system on ATRP was studied systematically. Most of the polymerizations with DPPMP ligand were well controlled with a linear increase in the number‐average molecular weights (Mn) versus conversion and relatively low molecular weight distributions (Mw/Mn = 1.10–1.3) being observed throughout the reactions, and the measured molecular weights matched the predicted values. Initially added iron(III) bromide improved the controllability of the polymerization reactions in terms of molecular weight control. The ratio of ligand to metal influenced the controllability of ATRP system, and the optimum ratio was found to be 2:1. It was shown that ATRP of MMA with FeX2/DPPMP catalytic system (X = Cl, Br) initiated by 2‐bromopropionitrile (BPN) was controlled more effectively in toluene than in polar solvents. The rate of polymerization increased with increasing the polymerization temperature and the apparent activation energy was calculated to be 56.7 KJ mol−1. In addition, reverse ATRP of MMA was able to be successfully carried out using AIBN in toluene at 80 °C. Polymerization of styrene (St) was found to be controlled well by using the PEBr/FeBr2/DPPMP system in DMF at 110 °C. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 2922–2935, 2008
Fabrication of thermosensitive PCL‐PNIPAAm‐PCL triblock copolymeric micelles for drug delivery
Authors: Chang Cong , Wei Hua , Quan Chang‐Yun , Li Yong‐Yong , Liu Jia , Wang Zong‐Chun , Cheng Si‐Xue , Zhang Xian‐Zheng , Zhuo Ren‐Xi 
Published: March 2008

AbstractA series of thermosensitive ABA type triblock poly(ε‐caprolactone)‐b‐poly(N‐isopropylacrylamide)‐b‐poly(ε‐caprolactone) (PCL‐PNIPAAm‐PCL) copolymers with different molecular weights were synthesized by the combination of ring opening polymerization and reversible addition‐fragmentation chain transfer (RAFT) polymerization. The critical micelle concentrations (CMCs) of the resulted four triblock copolymers in aqueous solution were determined to be 33.8, 39.8, 35.5, and 41.7 mg/L, respectively, by fluorescence spectroscopy using pyrene as a fluorescence probe. Optical absorption measurements showed that the lower critical solution temperatures (LCSTs) of the copolymers were 35.8, 36.2, 35.2, and 36.2 °C, respectively, in distilled water, and 33.9, 34.2, 33.3, 34.6 °C, respectively, in PBS (pH = 6.8, I = 0.1). Transmission electron microscopy (TEM) showed that the self‐assembled micelles exhibited a well‐defined spherical shape with diameter of around 100 nm. The drug‐loaded PCL‐PNIPAAm‐PCL micelles displayed thermosensitive controlled release behaviors. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 3048–3057, 2008
Predictors of mucoid Pseudomonas colonization in cystic fibrosis patients
Authors: Levy Hara , Kalish Leslie A. , Cannon Carolyn L. , García K. Christopher , Gerard Craig , Goldmann Don , Pier Gerald B. , Weiss Scott T. , Colin A.A. 
Published: March 2008

AbstractRationaleChronic mucoid Pseudomonas aeruginosa within the airway in cystic fibrosis (CF) patients can determine prognosis. Understanding the risk factors of mucoid P. aeruginosa acquisition may change how we deliver care. This study aims to evaluate whether presence of risk factors reported to predict disease severity including gender, CFTR genotype, bacterial organisms in airway cultures, and serum levels of vitamins A and E, albumin, C‐reactive protein, alpha 1‐antitrypsin, and immunoglobulins increased the risk of mucoid P. aeruginosa acquisition.MethodsPrimary endpoint was age at first transition from negative to positive culture for mucoid P. aeruginosa. Cox proportional hazards regression with time‐dependent covariates examined development of mucoid P. aeruginosa infection and its association with longitudinally measured serum biomarkers, pulmonary function, and culture results for other organisms.ResultsMedian ages at CF diagnosis and at first culture were 0.55 and 5.7 years, respectively. Median number of cultures/patient was 17. Of the 323 subjects, 150 developed mucoid P. aeruginosa during a median 8.1 years' follow‐up. In multivariate analysis, gender (relative hazard [RH] 0.55 for male vs. female, P = 0.001), number of DF508 alleles (RH 1.66 for 1 or 2 vs. 0, P = 0.04), FEV1 % (RH 1.16 for 10% decrease, P = 0.008), and most recent Staphylococcus aureus status (RH 0.24 for positive vs. negative, P < 0.0001) remained statistically significant.ConclusionFemale gender, number of DF508 alleles, decreased lung function, and lack of S. aureus on recent sputum culture are important risk factors for early detection of mucoid P. aeruginosa. Pediatr Pulmonol. 2008; 43:463–471. © 2008 Wiley‐Liss, Inc.
Association between sequence variants at 17q12 and 17q24.3 and prostate cancer risk in European and African Americans
Authors: Sun Jielin , Purcell Lina , Gao Zhengrong , Isaacs Sarah D. , Wiley Kathleen E. , Hsu Fang‐Chi , Liu Wennuan , Duggan David , Carpten John D. , Grönberg Henrik , Xu Jianfeng , Chang Bao‐Li , Partin Alan W. , Walsh Patrick C. , Isaacs William B. , Zheng S. Lilly 
Published: March 2008

AbstractBackgroundThree SNPs at 17q12 and four SNPs at 17q24.3 were recently identified to be associated with prostate cancer risk using a genome‐wide association study.MethodsWe evaluated these 7 SNPs in two hospital‐based case–control study populations, including European Americans (EA; 1,563 cases and 576 controls) and African Americans (AA; 364 cases and 353 controls).ResultsEach of the reported risk alleles of these seven SNPs were more common in cases than in controls among EA and AA. The differences were highly significant in EA (P = 10−4) and marginally significant in AA (P = 0.04) for SNPs at 17q12. In contrast, the differences were not statistically significant in EA or AA for SNPs at 17q24.3, but were marginally significant for two SNPs (P = 0.04–0.06) when EA and AA subjects were combined. Similar results were obtained when genotype and haplotype frequencies between cases and controls were analyzed. These risk variants were not associated with more aggressive prostate cancer or other clinical variables such as TNM stage, pre‐operative PSA, or age at diagnosis.ConclusionsResults from our study provide the first confirmation of these 17q SNPs as novel prostate cancer susceptibility loci in EA and the first indication that these two loci may also play roles in prostate cancer risk among AA. Prostate 68: 691–697, 2008. © 2008 Wiley‐Liss, Inc.
Fast protein tertiary structure retrieval based on global surface shape similarity
Authors: Sael Lee , Li Bin , La David , Fang Yi , Ramani Karthik , Rustamov Raif , Kihara Daisuke 
Published: March 2008

AbstractCharacterization and identification of similar tertiary structure of proteins provides rich information for investigating function and evolution. The importance of structure similarity searches is increasing as structure databases continue to expand, partly due to the structural genomics projects. A crucial drawback of conventional protein structure comparison methods, which compare structures by their main‐chain orientation or the spatial arrangement of secondary structure, is that a database search is too slow to be done in real‐time. Here we introduce a global surface shape representation by three‐dimensional (3D) Zernike descriptors, which represent a protein structure compactly as a series expansion of 3D functions. With this simplified representation, the search speed against a few thousand structures takes less than a minute. To investigate the agreement between surface representation defined by 3D Zernike descriptor and conventional main‐chain based representation, a benchmark was performed against a protein classification generated by the combinatorial extension algorithm. Despite the different representation, 3D Zernike descriptor retrieved proteins of the same conformation defined by combinatorial extension in 89.6% of the cases within the top five closest structures. The real‐time protein structure search by 3D Zernike descriptor will open up new possibility of large‐scale global and local protein surface shape comparison. Proteins 2008. © 2008 Wiley‐Liss, Inc.
Dendritic‐targeting GABA neurons in monkey prefrontal cortex: Comparison of somatostatin‐ and calretinin‐immunoreactive axon terminals
Authors: Melchitzky Darlene S. , Lewis David A. 
Published: March 2008

AbstractDifferent subclasses of γ‐aminobutyric acid (GABA) cortical neurons can be distinguished by their content of neuropeptides such as somatostatin (SST), or calcium‐binding proteins such as calretinin (CR). SST, but not CR, neurons have been reported to be altered in the prefrontal cortex (PFC) of subjects with schizophrenia. Understanding the functional significance of the SST neuron disturbances in schizophrenia requires knowledge of the specialized synaptic circuitry of these neurons relative to that of CR neurons. Consequently, we used immuno‐electron microscopy to examine the synaptic type and postsynaptic targets of SST‐immunoreactive (IR) axon terminals in monkey PFC and compared these findings with similar data for CR‐IR axon terminals. SST‐IR axon terminals formed exclusively symmetric synapses and contacted only dendritic shafts (86%) and dendritic spines (14%), whereas CR‐IR terminals also formed synapses with cell bodies. The postsynaptic targets of SST‐IR axon terminals also differed across layers with synapses onto dendritic spines more frequent in the superficial (20%) than in the deep (8%) layers. Dual‐label immunoelectron microscopy revealed that CR‐IR axon terminals targeted GABA‐IR dendritic shafts with a greater frequency (60%) than did SST‐IR axon terminals (21.5%). Conversely, SST‐IR axon terminals contacted unlabeled dendritic shafts, presumably belonging to pyramidal neurons, more frequently than did CR‐IR axon terminals (57% vs. 19%, respectively). This specialized synaptic circuitry of SST neurons in the primate PFC suggests that the alterations of these neurons in schizophrenia is likely to have distinct functional consequences. Synapse 62:456–465, 2008. © 2008 Wiley‐Liss, Inc.
Altered synaptic synchrony in motor nerve terminals lacking P/Q‐calcium channels
Authors: Depetris Rafael S. , Nudler Silvana I. , Uchitel Osvaldo D. , Urbano Francisco J. 
Published: March 2008

AbstractThe variance in synaptic delays among endplate potentials events (referred here as jitter) was measured to study the contribution of voltage dependent calcium channels to transmission synchronicity in neuromuscular synapses from wild type and α‐1A knockout mice (i.e., lacking P/Q type calcium channels). Knockout synapses presented higher jitter values than wild type ones under a wide range of extracellular calcium concentration ([Ca2+]o) values. Accordingly, wild type synapses showed less synchronic neurotransmitter release when P/Q type calcium channels were partially blocked as well as under lower [Ca2+]o. In the knockout synapses, N‐type calcium channels mediated neurotransmitter release in a more temporally precise way than the R‐type ones. Our results suggest that the type of calcium channels mediating transmitter release influenced the degree of synaptic synchrony. Thus, these results provide insight on the mechanisms underlying several pathologies associated with P/Q type calcium channels. Synapse 62:466–471, 2008. © 2008 Wiley‐Liss, Inc.