bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synergistic effect of immobilized laminin and nerve growth factor on PC12 neurite outgrowth
Authors: Achyuta Anil Kumar H. , Cieri Rocco , Unger Kristina , Murthy Shashi K. 
Published: January 2009

AbstractImmobilized extracellular matrix proteins and neurotrophins have been extensively studied to enhance neuronal adhesion and proliferation on surfaces for applications in nerve tissue engineering and neuroprosthetic devices. This article describes how the coimmobilization of laminin, an extracellular matrix protein and nerve growth factor (NGF), a neurotrophin can enhance neurite outgrowth observed separately with each type of molecule. In the absence of immobilized NGF, PC12 neurite outgrowth is influenced strongly by the presence of NGF in solution and unaffected by significant increases in laminin surface density (18.7–93.5 ng/mm2). However, when both laminin and NGF are immobilized together, the surface density of laminin is an important factor in determining whether or not the neurite outgrowth‐promoting effect of NGF can be obtained. PC12 neurite outgrowth on surfaces with coimmobilized laminin and NGF with surface densities of 27.6 ng/mm2 and 1.4 ng/mm2, respectively, are similar to that observed on surfaces with immobilized laminin and dissolved NGF. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
293 cell cycle synchronisation adenovirus vector production
Authors: Ferreira Tiago B. , Perdigão Ricardo , Silva Ana C. , Zhang Changhe , Aunins John G. , Carrondo Manuel J.T. , Alves Paula M. 
Published: January 2009

AbstractAs the market requirements for adenovirus vectors (AdV) increase, the maximisation of the virus titer per culture volume per unit time is a key requirement. However, despite the fact that 293 cells can grow up to 8 × 106 cell/mL in simple batch mode operations, for optimal AdV infection a maximum cell density of 1 × 106 cell/mL at infection time has usually been utilized due to the so called “cell density effect”. In addition, AdV titer appears to be dependent upon cell cycle phase at the time of infection. To evaluate the dependence of AdV production upon cell cycle phase, 293 cells were chemically synchronised at each phase of the cell cycle; a 2.6‐fold increase on AdV cell specific titer was obtained when the percentage of cells at the S phase of the cell cycle was increased from 36 to 47%; a mathematical equation was used to relate AdV cell specific productivities with cell synchronisation at the S phase using this data. To avoid the use of chemical inhibitors, a temperature shift strategy was also used for synchronisation at the S phase. S phase synchronisation was obtained by decreasing the culture temperature to 31°C during 67 h and restoring it to 37°C during 72 h. By using this strategy we were able to synchronise 57% of the population in the S phase of the cell cycle obtaining an increase of 7.3‐fold on AdV cell specific titer after infection. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
Characterization of gene localization and accessibility in DHFR‐amplified CHO cells
Authors: Jiang Zhou , Sharfstein Susan T. 
Published: January 2009

AbstractEfficient transcription is critical for high yields of recombinant proteins by mammalian cells. We previously reported that dihydrofolate reductase (DHFR)‐mediated gene amplification can augment transcriptional rates as well as increasing gene copy numbers in Chinese hamster ovary (CHO) cells.1 In an attempt to elucidate the mechanisms involved, we have employed several approaches to identify the epigenetic differences between cell clones with varying transcriptional rates. Transgene placement and accessibility varies between unrelated parental cell clones with differential transcriptional rates. However, we did not observe any apparent epigenetic differences between parental clones and their amplified progeny, indicating undiscovered regulatory mechanisms are responsible for the augmentation of transcriptional rates upon DHFR‐mediated amplification. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
Endovascular balloon occlusion for catheter‐induced large artery perforation in the catheterization laboratory
Authors: Masson Jean‐Bernard , Bugami Saad Al , Webb John G. 
Published: January 2009

AbstractBackground:Vessel perforation is a complication that cannot be completely avoided in the setting of endovascular procedures. When a large noncompressible artery is disrupted, uncontrolled bleeding may lead to hemodynamic collapse. Endovascular occlusion may provide rapid control of hemorrhage and facilitate definitive therapy; yet, occlusion balloons are not commonly utilized in the cardiac catheterization laboratory.Methods:We describe our experience with the use of dedicated occlusion balloons for the management of catheter‐induced major bleeding events. Endovascular occlusion was utilized to control severe bleeding in five patients with perforation of the aorta, iliac, femoral, or pulmonary artery.Results:Acute control of hemorrhage was achieved in all patients with hemodynamic stabilization in four of five cases. Endovascular balloon occlusion facilitated definitive therapy with surgical repair in two patients, covered stent deployment in one patient and transcatheter vessel occlusion in one patient. Care was withdrawn in one elderly patient with multiple comorbidities. All four patients who survived the procedure were discharged alive from the hospital.Conclusions:In most cases of severe catheter‐induced bleeding, endovascular balloon occlusion provide a safe, rapid, and effective means of temporary bleeding control. © 2009 Wiley‐Liss, Inc.
Combination antiplatelet therapy in patients with peripheral arterial disease: Is the best therapy aspirin, clopidogrel, or both?
Authors: Mohler Emile R. 
Published: January 2009

AbstractPatients with peripheral arterial disease (PAD) are at increased risk of atherothrombotic events. Antiplatelet therapy and risk‐factor modification represent the basis of treatment to prevent the ischemic events associated with PAD. The efficacy of aspirin in the secondary prevention of myocardial infarction and stroke has been demonstrated in a large number of trials. More recently, however, the clinical benefit of clopidogrel compared with aspirin in patients with PAD was confirmed. Many clinical trials have evaluated the efficacy of combination antiplatelet therapy in the prevention of recurrent ischemic events in patients with atherosclerotic vascular diseases. Although the results of these studies appear promising, the benefits resulting from dual antiplatelet therapy are counterbalanced by a significant increase in bleeding. Further studies are needed to establish the optimal antiplatelet therapy in the management and prevention of PAD. © 2009 Wiley‐Liss, Inc.
Antiplatelet therapy after endovascular intervention: Does combination therapy really work and what is the optimum duration of therapy?
Authors: Milani Richard V. 
Published: January 2009

AbstractThe number of patients undergoing peripheral interventions has increased in recent years, highlighting the need for a safe and effective protective antithrombotic therapy. Platelet inhibition following coronary intervention is associated with a significantly reduced risk of graft occlusion, and has been acknowledged to be safe and effective in patients with peripheral arterial disease. Monotherapy with either aspirin or clopidogrel, reduces the rate of stroke, myocardial infarction, and cardiovascular death in patients suffering from peripheral arterial disease. Limited data from clinical trials investigating combination therapy of aspirin with ticlopidine or clopidogrel in patients undergoing endovascular interventions, have suggested the potential for a reduction in cardiovascular events. Nevertheless, the optimal duration of postintervention antiplatelet therapy remains to be defined. © 2009 Wiley‐Liss, Inc.
Closing of a right ventricle perforation with a vascular closure device
Authors: Petrov Ivo , Dimitrov Christo 
Published: January 2009

AbstractVascular closure devices are a proven alternative to pure mechanical femoral compression after endovascular procedures. Their off‐label use is uncommon and is usually restricted for atypical vascular sites—subclavian arteries and even descending aorta. We report for the first time a case of a successful percutaneous closure of a perforated right ventricle, using the Angio Seal femoral closure device. This was done after an attempt for pericardiocentesis in a high risk patient with carcinoma and cardiac tamponade, which was complicated with perforation of the right ventricle. The closure device successfully stopped the bleeding in the pericardium and spared the patient the need of open surgery and general anesthesia. A successful pericardial drainage was performed after this, and the patient was discharged with clinical improvement. Our literature review did not find descriptions of similar application of a vascular closure device. Our opinion is that such approach is effective and safe and may be used in some extreme and critical situations and in patients at high surgical risk. © 2009 Wiley‐Liss, Inc.
An in vitro model system for cytoskeletal confinement
Authors: Köster Sarah , Pfohl Thomas 
Published: January 2009

AbstractThe motility, shape, and functionality of the cell depend sensitively on cytoskeletal mechanics which in turn is governed by the properties of filamentous proteins ‐ mainly actin, microtubules, and intermediate filaments. These biopolymers are confined in the dense cytoplasm and therefore experience strong geometric constraints on their equilibrium thermal fluctuations. To obtain a better understanding of the influence of confinement on cytoskeletal filaments we study the thermal fluctuations of individual actin filaments in a microfluidic in vitro system by fluorescence microscopy and determine the persistence length of the filaments by analyzing the radial distribution function. A unique feature of this method is that we obtain the persistence length without detailed knowledge of the complete contour of the filament which makes the technique applicable to a broad range of biological polymers, including those with a persistence length smaller than the optical resolution. Cell Motil. Cytoskeleton 2009. © 2009 Wiley‐Liss, Inc.
Microtubule‐dependent motility and orientation of the cortical endoplasmic reticulum in elongating characean internodal cells
Authors: Foissner Ilse , Menzel Diedrik , Wasteneys Geoffrey O. 
Published: January 2009

AbstractMotility of the endoplasmic reticulum (ER) is predominantly microtubule‐ dependent in animal cells but thought to be entirely actomyosin‐dependent in plant cells. Using live cell imaging and transmission electron microscopy to examine ER motility and structural organization in giant internodal cells of characean algae, we discovered that at the onset of cell elongation, the cortical ER situated near the plasma membrane formed a tight meshwork of predominantly transverse ER tubules that frequently coaligned with microtubules. Microtubule depolymerization increased mesh size and decreased the dynamics of the cortical ER. In contrast, perturbing the cortical actin array with cytochalasins did not affect the transverse orientation but decreased mesh size and increased ER dynamics. Our data suggest that myosin‐dependent ER motility is confined to the ER strands in the streaming endoplasm, while the more sedate cortical ER uses microtubule‐based mechanisms for organization and motility during early stages of cell elongation. We show further that the ER has an inherent, NEM‐sensitive dynamics which can be altered via interaction with the cytoskeleton and that tubule formation and fusion events are cytoskeleton‐independent. Cell Motil. Cytoskeleton 2009. © 2009 Wiley‐Liss, Inc.
The Synthesis and in vivo Evaluation of 2′,2′‐Difluoro KRN7000
Authors: Leung Leo , Tomassi Cyrille , Van Beneden Katrien , Decruy Tine , Trappeniers Matthias , Elewaut Dirk , Gao Yifang , Elliott Tim , Al‐Shamkhani Aymen , Ottensmeier Christian , Werner Jörn M. , Williams Anthony , Van Calenbergh Serge , Linclau Bruno 
Published: January 2009

AbstractThe synthesis of 2′,2′‐difluoro KRN7000 is described. In vivo evaluation demonstrates that this fluorinated glycolipid induces CD1d‐dependent TCR activation of NKT cells, with a bias towards Th2 cytokine production.magnified image
Internalization of annexin A5‐functionalized iron oxide particles by apoptotic Jurkat cells
Authors: van Tilborg Geralda A. F. , Geelen Tessa , Duimel Hans , Bomans Paul H. H. , Frederik Peter M. , Sanders Honorius M. H. F. , Deckers Niko M. , Deckers Roel , Reutelingsperger Chris P. M. , Strijkers Gustav J. , Nicolay Klaas 
Published: January 2009

AbstractApoptosis plays an important role in the etiology of various diseases. Several studies have reported on the use of annexin A5‐functionalized iron oxide particles for the detection of apoptosis with MRI, both in vitro and in vivo. The protein annexin A5 binds with high affinity to the phospholipid phosphatidylserine, which is exposed in the outer leaflet of the apoptotic cell membrane. When co‐exposed to apoptotic stimuli, this protein was shown to internalize into endocytic vesicles. Therefore in the present study we investigated the possible internalization of commercially available annexin A5‐functionalized iron oxide particles (r1 = 34.0 ± 2.1 and r2 = 205.0 ± 10.4 mm−1 s−1 at 20 MHz), and the effects of their spatial distribution on relaxation rates R, R2 and R1. Two different incubation procedures were performed, where (1) Jurkat cells were either incubated with the contrast agent after induction of apoptosis or (2) Jurkat cells were simultaneously incubated with the apoptotic stimulus and the contrast agent. Transmission electron microscopy images and relaxation rates showed that the first incubation strategy mainly resulted in binding of the annexin A5‐iron oxide particles to the cell membrane, whereas the second procedure allowed extensive membrane‐association as well as a small amount of internalization. Owing to the small extent of internalization, only minor differences were observed between the ΔR/ΔR2 and ΔR2/ΔR1 ratios of cell pellets with membrane‐associated or internalized annexin A5 particles. Only the increase in R1 (ΔR1) appeared to be diminished by the internalization. Internalization of annexin A5‐iron oxide particles is also expected to occur in vivo, where the apoptotic stimulus and the contrast agent are simultaneously present. Where the extent of internalization in vivo is similar to that observed in the present study, both T2‐ and T‐weighted MR sequences are considered suitable for the detection of these particles in vivo. Copyright © 2009 John Wiley & Sons, Ltd.
Solving the fractional order Bloch equation
Authors: Magin Richard , Feng Xu , Baleanu Dumitru 
Published: January 2009

AbstractNuclear magnetic resonance (NMR) is a physical phenomenon widely used in chemistry, medicine, and engineering to study complex materials. NMR is governed by the Bloch equation, which relates a macroscopic model of magnetization to applied radiofrequency, gradient and static magnetic fields. Simple models of materials are well described by the classical first order dynamics of precession and relaxation inherent in the vector form of the Bloch equation. Fractional order generalization of the Bloch equation presents an opportunity to extend its use to describe a wider range of experimental situations involving heterogeneous, porous, or composite materials. Here we describe the generalization of the Bloch equation in terms of Caputo fractional derivatives of order α (0 < α < 1) for a single spin system in a static magnetic field at resonance. The results are expressed in terms of the Mittag–Leffler function—a generalized exponential function that converges to the classical case when α = 1. © 2009 Wiley Periodicals, Inc. Concepts Magn Reson Part A 34A: 16–23, 2009.
Dynamic expression of the Slit‐Robo GTPase activating protein genes during development of the murine nervous system
Authors: Bacon Claire , Endris Volker , Rappold Gudrun 
Published: January 2009

AbstractWe investigated the expression of the three known Slit‐Robo GTPase activating protein (srGAP) genes in the developing murine nervous system using in situ hybridization. The three genes are expressed during embryonic and early postnatal development in the murine nervous system, showing a distinct pattern of expression in the olfactory system, the eye, forebrain and midbrain structures, the cerebellum, the spinal cord, and dorsal root ganglia, which we discuss in relation to Slit‐Robo expression patterns and signaling pathways. We also report srGAP2 expression in zones of neuronal differentiation and srGAP3 in ventricular zones of neurogenesis in many different tissues of the central nervous system (CNS). Compared to srGAP2 and srGAP3, the onset of srGAP1 expression is later in most CNS tissues. We propose that these differences in expression point to functional differences between these three genes in the development of neural tissues. J. Comp. Neurol. 513:224–236, 2009. © 2009 Wiley‐Liss, Inc.
Axotomy alters alternative splicing of choline acetyltransferase in the rat dorsal motor nucleus of the vagus nerve
Authors: Saito Atsushi , Sato Takashi , Okano Hiroyuki , Toyoda Ken‐Ichiro , Bamba Hitoshi , Kimura Shin , Bellier Jean‐Pierre , Matsuo Akinori , Kimura Hiroshi , Hisa Yasuo , Tooyama Ikuo 
Published: January 2009

AbstractCholine acetyltransferase of the peripheral type (pChAT) is a splice variant that lacks exons 6–9 of the common‐type ChAT (cChAT); the role of pChAT remains unknown. We investigated the expression of pChAT and cChAT after axotomy to try to elucidate its function. In the dorsal motor nucleus of the vagus nerve (DMNV), nucleus ambiguus (NA), and hypoglossal nucleus (HN) of control rats, we observed neural expression of cChAT but no pChAT‐positive neurons. Following nerve transection, we clearly detected pChAT‐labeled neurons in the DMNV and weakly labeled neurons in the NA, but pChAT was not seen in the HN. In the DMNV, the mean number of cChAT‐positive neurons decreased rapidly to 40.5% of control at 3 days post transection, and to 5.0% of control after 7 days. The number of cChAT‐positive neurons then gradually increased and reached a plateau of about 25% of control value at 28 days post transection. pChAT‐positive neurons did not appear until 7 days after transection. On the same day, pChAT mRNA was detected in the DMNV neurons by reverse transcription‐polymerase chain reaction (RT‐PCR) by using laser capture microdissection. The number of pChAT‐positive neurons gradually decreased, and only 10% of the cholinergic neurons retained pChAT expression 56 days post transection. Double‐immunofluorescence analysis showed that some of the DMNV neurons expressed both cChAT and pChAT upon recovery from axotomy. These results suggest that the expression of pChAT is associated with the regenerative or degenerative processes of motoneurons especially for general visceral efferents. J. Comp. Neurol. 513:237–248, 2009. © 2009 Wiley‐Liss, Inc.
Nanostructured Vanadium Oxide Model Catalysts for Selective Oxidation Reactions
Authors: Hess Christian 
Published: January 2009

AbstractControlled synthesis based on spectroscopic characterization, structure, and catalytic performance of mesoporous silica SBA‐15‐supported vanadium oxide model catalysts (see TEM image) are reviewed. The effect of water on the structure and dispersion of highly dispersed vanadium oxide is discussed in the light of recent results in multiple in situ spectroscopy.magnified imageCharacterization of the synthesis, structure, and catalytic performance of vanadium oxide catalysts supported on mesoporous silica SBA‐15 for selective oxidation reactions are reviewed. Controlled synthesis on the basis of surface functionalization and ion exchange allows homogeneous deposition of vanadium oxide within the pores of SBA‐15. Catalytic tests on the selective oxidation of methanol and propane demonstrate the full catalytic function of these model powder catalysts. Characterization of the dehydrated state by vibrational spectroscopy provides insight into the structure of SBA‐15‐supported vanadium oxide at low loadings. The effect of water on the structure and dispersion of highly dispersed vanadium oxide is discussed in light of recent results from multiple in situ spectroscopy.
A study of multicast congestion control for UMTS
Authors: Alexiou Antonios , Bouras Christos , Papazois Andreas 
Published: January 2009

AbstractIn this paper, we study the applicability of multicast congestion control over universal mobile telecommunications system (UMTS) networks. We analyze two well‐known multicast congestion control schemes for fixed networks, namely TCP‐friendly multicast congestion control and pragmatic general multicast congestion control. We investigate their behavior when they are employed in UMTS networks and we analyze the problems arose when these mechanisms are applied over the wireless links of the UMTS terrestrial radio‐access network. Additionally, we propose necessary improvements to these legacy schemes and explain the necessity of these modifications. The proposed schemes are implemented in the ns‐2 network simulator and are evaluated under various network conditions and topologies. Finally, we measure the performance of the proposed modified schemes and compare them with the corresponding legacy mechanisms. Copyright © 2009 John Wiley & Sons, Ltd.
Neonatal separation stress reduces glial fibrillary acidic protein‐ and S100β‐immunoreactive astrocytes in the rat medial precentral cortex
Authors: Musholt Kristina , Cirillo Giovanni , Cavaliere Carlo , Rosaria Bianco Maria , Bock Joerg , Helmeke Carina , Braun Katharina , Papa Michele 
Published: January 2009

AbstractThe interactions between the mother/parents and their offspring provides socioemotional input, which is essential for the establishment and maintenance of synaptic networks in prefrontal and limbic brain regions. Since glial cells are known to play an important role in developmental and experience‐driven synaptic plasticity, the effect of an early adverse emotional experience induced by maternal separation for 1 or 6 h on the expression of the glia specific proteins S100β and glial fibrillary acidic protein (GFAP) was quantitatively analyzed in anterior cingulate cortex, hippocampus, and precentral medial cortex. Three animal groups were analyzed at postnatal day 14: (i) separated for 1 h; (ii) separated for 6 h; (iii) undisturbed (control). Twenty‐four hours after stress exposure, the stressed brains showed significantly reduced numbers of S100β‐immunoreactive (ir) cells in the anterior cingulate cortex (6‐h stress) and in the precentral medial cortex (1‐ and 6‐h stress). Significantly reduced numbers of GFAP‐ir cells were observed only in the medial precentral cortex (1‐ and 6‐h stress); no significant changes were observed in the anterior cingulate cortex. No significant changes of the two glial markers were observed in the hippocampus. Double‐labeling experiments with GFAP and pCREB revealed pCREB labeling only in the hippocampus, where the stressed brains (1 and 6 h) displayed significantly reduced numbers of GFAP/pCREB‐ir glial cells. The observed downregulation of glia‐specific marker proteins is in line with our hypothesis that emotional experience can alter glia cell activation in the juvenile limbic system. © 2009 Wiley Periodicals, Inc. Develop Neurobiol, 2009