bluuebunny/crossref_metadata_2025_split huggingface dataset:
Culture conditions affect proliferative responsiveness of olfactory ensheathing glia to neuregulins
Authors: De Mello T. R. , Busfield S. , Dunlop S. A. , Plant G. W. 
Published: March 2007

AbstractOlfactory ensheathing glia (OEG) have been used to improve outcome after experimental spinal cord injury and are being trialed clinically. Their rapid proliferation in vitro is essential to optimize clinical application, with neuregulins (NRG) being potential mitogens. We examined the effects of NRG‐1β, NRG‐2α, and NRG3 on proliferation of p75‐immunopurified adult OEG. OEG were grown in serum‐containing medium with added bovine pituitary extract and forskolin (added mitogens) or in serum‐containing medium (no added mitogens). Cultures were switched to chemically defined medium (no added mitogens or serum), NRG added and OEG proliferation assayed using BrdU. OEG grown initially with added mitogens were not responsive to added NRGs and pre‐exposure to forskolin and pituitary extract increased basal proliferation rates so that OEG no longer responded to added NRG. However, NRG promoted proliferation but only if cells were initially grown in mitogen‐free medium. Primary OEG express ErbB2, ErbB3, and small levels of ErbB4 receptors; functional blocking indicates that ErbB2 and ErbB3 are the main NRG receptors utilized in the presence of NRG‐1β. The long‐term stimulation of OEG proliferation by initial culture conditions raises the possibility of manipulating OEG before therapeutic transplantation. © 2007 Wiley‐Liss, Inc.
Ferritin—a mediator of apoptosis?
Authors: Bresgen Nikolaus , Ohlenschläger Ingo , Fiedler Brigitte , Wacht Nathalie , Zach Susanne , Dunkelmann Bettina , Arosio Paolo , Kuffner Elisabeth , Lottspeich Friedrich , Eckl Peter M. 
Published: March 2007

AbstractPreviously we have demonstrated an apoptosis inducing activity for a rat hepatocyte conditioned medium (CM) presumably mediated by acidic isoferritins. Here, we present support for this assumption since isoferritins purified from different rat hepatocyte CM significantly enhanced the frequency of apoptotic cells in primary rat hepatocytes, an effect completely inhibited by a neutralizing anti‐H‐ferritin antibody. The apoptosis induction appears to be related to a 43 kDa ferritin subunit contained in the isoferritins released from primary hepatocytes, presumably representing a ferritin heavy/light chain heterodimer. In addition, these isoferritins immunologically crossreact with antibodies raised against placental isoferritin p43‐PLF (which also contains a 43 kDa ferritin subunit) and melanoma‐derived H‐chain ferritin, representing ferritin isoforms which reveal immunomodulatory properties. Furthermore, p53 and FasL are upregulated upon isoferritin treatment in a time dependent mode, and apoptosis induction can be suppressed by neutralizing anti‐FasL antibodies. Proapoptotic Bid is upregulated too and translocated into mitochondria in primary hepatocytes exposed to the isoferritins purified from the CM. Finally, epidermal growth factor (EGF) and dexamethasone (DEX), which counteract proapoptotic mitochondrial signalling, almost completely abolished the proapoptotic effect of the hepatocyte derived isoferritins. In conclusion, our findings demonstrate that acidic isoferritins with homology to immunomodulatory ferritin isoforms (p43‐PLF, melanoma‐derived‐H‐chain ferritin) are released from hepatocytes in vitro, and are able to stimulate upregulation of p53 and mediate apoptosis involving Fas (CD95) signalling as well as addressing the intrinsic mitochondrial proapoptotic pathway. J. Cell. Physiol. 212: 157–164, 2007. © 2007 Wiley‐Liss, Inc.
Human papillomavirus‐16 E7 interacts with siva‐1 and modulates apoptosis in HaCaT human immortalized keratinocytes
Authors: Severino Anna , Abbruzzese Claudia , Manente Lucrezia , Valderas Álvaro Avivar , Mattarocci Stefano , Federico Antonio , Starace Giuseppe , Chersi Alberto , Mileo Anna Maria , Paggi Marco G. 
Published: March 2007

AbstractThe viral factor E7 plays a key role in the well‐established association between “high‐risk” Human Papillomavirus (HPV) infection and the development of epithelial malignant tumors, as uterine cervix and ano‐genital cancer. To delve into the molecular mechanisms of HPV‐mediated cell transformation, we searched for novel potential cellular targets of the HPV‐16 E7 oncoprotein, by means of the yeast two‐hybrid technique, identifying a protein–protein interaction between HPV‐16 E7 and the pro‐apoptotic cellular factor Siva‐1. Using co‐precipitation assays and the “PepSets” technique, we confirmed this physical interaction and mapped accurately, for both proteins, the amino acid residues involved. Additionally, we found that HPV‐16 E7 competed in vitro with the binding of the Bcl‐XL anti‐apoptotic factor to Siva‐1, an interaction that has a major inference in UV radiation‐induced apoptosis. In HaCaT immortalized human keratinocytes, forced HPV‐16 E7 expression by retroviral infection caused Siva‐1 transcript up‐regulation, detected by cDNA macroarray hybridization and real‐time quantitative PCR, paralleled by an increased amount of protein. Confirming the anti‐apoptotic role of HPV‐16 E7 in the HaCaT cellular model, evaluated by nuclear morphology, we also found that Siva‐1 expression produced a significant increase of the apoptotic rate in UV radiation‐exposed HaCaT cells, and that this effect resulted explicitly counteracted by HPV‐16 E7. Being apoptosis a key physiological process for the elimination of irreversibly injured cells, the anti‐apoptotic role of HPV‐16 E7, performed at least by its interference with Siva‐1, can be considered an additional mechanism for the survival of damaged, potentially transforming, cell clones. J. Cell. Physiol. 212: 118–125, 2007. © 2007 Wiley‐Liss, Inc.
Matrix metalloproteinase activity is necessary for thymosin beta 4 promotion of epithelial cell migration
Authors: Qiu Ping , Kurpakus‐Wheater Michelle , Sosne Gabriel 
Published: March 2007

AbstractStudies from our laboratory provide substantial evidence that thymosin beta 4, (Tβ4), an actin‐sequestering protein, promotes corneal wound healing through its ability to stimulate epithelial cell migration. Matrix metalloproteinases (MMPs), which are expressed in a wide variety of tissues including the cornea, also play a key role in epithelial cell migration and wound healing. In this study we investigated the role of MMPs in Tβ4‐stimulated corneal epithelial cell migration. In Boyden chamber assays, XG076, an inhibitor of the conversion of pro‐ to active MMPs, had no effect on epithelial cell migration stimulated by exogenous activated MMP‐1. However, in in vitro migration assays where the activation of pro‐MMPs was blocked, XG076 significantly inhibited cell migration and wound healing in the presence or absence of Tβ4. GM6001, a broad‐spectrum inhibitor of active MMPs and selective MMP inhibitors, also suppressed Tβ4‐stimulated cell migration. Tβ4 upregulated MMP‐1 gene and protein expression in primary human corneal epithelial cells and in transformed human corneal epithelial cells following scrape wounding. From these results we conclude that MMP catalytic activity is necessary for Tβ4 promotion of epithelial cell migration. These novel findings are the first to demonstrate a functional link between the two. J. Cell. Physiol. 212: 165–173, 2007. © 2007 Wiley‐Liss, Inc.
Measurement of liver fat content using selective saturation at 3.0 T
Authors: Cotler Scott J. , Guzman Grace , Layden‐Almer Jennifer , Mazzone Theodore , Layden Thomas J. , Zhou Xiaohong Joe 
Published: March 2007

AbstractPurposeTo validate an MRI technique for measuring liver fat content by calibrating MRI readings with liver phantoms and comparing MRI measurements in human subjects with estimates of liver fat content on liver biopsy specimens.Materials and MethodsThe MRI protocol consisted of fat and water imaging by selective saturation using a 3.0‐T scanner. A water phantom and liver phantoms were scanned before each of 10 human subjects who underwent a liver biopsy to assess for nonalcoholic fatty liver disease (NAFLD). Liver fat content in human subjects was derived from a calibration curve generated by scanning the phantoms. Liver fat was also estimated by optical image analysis and pathologists' assessment of histologic sections.ResultsMRI measurements of the liver phantoms were highly reproducible. Measurements of liver fat content in human subjects made by MRI in two areas of the liver were strongly correlated (r = 0.98, P < 0.001). MRI measurements were highly associated with estimates of liver fat content made by optical image analysis (r = 0.96, P < 0.001) and with estimates made by the pathologists (r = 0.93, P < 0.001).ConclusionWe validated a technique for quantifying liver fat content based on selective fat and water imaging. The technique is accurate and reproducible and provides a noninvasive method to obtain serial measurements of liver fat content in human subjects. J. Magn. Reson. Imaging 2007. © 2007 Wiley‐Liss, Inc.
Molecular imaging and therapy of atherosclerosis with targeted nanoparticles
Authors: Wickline Samuel A. , Neubauer Anne M. , Winter Patrick M. , Caruthers Shelton D. , Lanza Gregory M. 
Published: March 2007

AbstractAdvances in bionanotechnology are poised to impact the field of cardiovascular diagnosis and therapy for decades to come. This review seeks to illustrate selected examples of newly developed diagnostic and therapeutic nanosystems that have been evaluated in experimental atherosclerosis, thrombosis, and vascular biology. We review a variety of nanotechnologies that are capable of detecting early cardiovascular pathology, as well as associated imaging approaches and conjunctive strategies for site‐targeted treatment with nanoparticle delivery systems. J. Magn. Reson. Imaging 2007. © 2007 Wiley‐Liss, Inc.
Four‐dimensional single breathhold magnetic resonance imaging using kt‐BLAST enables reliable assessment of left‐ and right‐ventricular volumes and mass
Authors: Jahnke Cosima , Nagel Eike , Gebker Rolf , Bornstedt Axel , Schnackenburg Bernhard , Kozerke Sebastian , Fleck Eckart , Paetsch Ingo 
Published: March 2007

AbstractPurposeTo prospectively determine the accuracy of four‐dimensional (4D) kt‐broad‐use linear acquisition speed‐up technique (BLAST) accelerated MRI (kt‐BLAST) for the assessment of left‐ventricular (LV) volumes and mass as well as right‐ventricular (RV) volumes in comparison to standard multiple breathhold cine imaging.Materials and MethodsA total of 40 patients with suspected or known coronary artery disease (CAD) underwent cardiac MRI. In each patient a standard multislice cine steady‐state free precession (SSFP) sequence was performed with complete ventricular coverage during multiple breathholds. Additionally, a kt‐BLAST‐accelerated 4D sequence with complete ventricular coverage was acquired during one single breathhold. For comparison of SSFP and kt‐BLAST, the following LV parameters were determined: end‐diastolic and end‐systolic volumes, ejection fraction, end‐diastolic diameter and mass. For comparison of RV dimensions, end‐diastolic and end‐systolic volumes and ejection fraction were assessed.ResultsLV volumes, ejection fraction, diameter, and mass showed a strong correlation between SSFP and kt‐BLAST (r = 0.98–0.99; P < 0.01). In addition, RV parameters demonstrated a high correlation (r = 0.97–0.98; P < 0.01). For all parameters, the calculated bias between both methods was found to be minimal (0.4–4%).Conclusion4D kt‐BLAST‐accelerated MRI enabled the accurate assessment of LV and RV quantitative parameters during one single breathhold when compared to standard multislice, multiple breathhold SSFP imaging. J. Magn. Reson. Imaging 2007. © 2007 Wiley‐Liss, Inc.
Assessment of human brain motion using CSPAMM
Authors: Soellinger Michaela , Ryf Salome , Boesiger Peter , Kozerke Sebastian 
Published: March 2007

AbstractPurposeTo quantify periodic displacement in the cranium using complementary spatial modulation of magnetization (CSPAMM) with harmonic phase (HARP) postprocessing.Materials and MethodsCSPAMM tagging sequence with separate tag‐line preparation in two orthogonal directions was applied on 10 healthy volunteers in combination with HARP for tissue displacement mapping.ResultsImportant features of brain dynamics, such as caudal displacement amplitude and the time‐to‐peak of the pulse wave were derived for six regions in the brain. Peak displacement values amounted to 0.18 ± 0.02 mm, 0.10 ± 0.01 mm, 0.09 ± 0.02 mm, and 0.04 ± 0.01 mm for regions in the pons, cerebellum, corpus callosum (splenium), and frontal lobe, respectively. Displacement values of the pons differed significantly from all other regions measured. With the additional information of the time‐to‐peak measure all six regions except the corpus callosum (splenium) and cerebellum can be distinguished. The values found suggest that the pulse wave travels from the brain stem first occipitally and then to the frontal lobe, where peak values appear later and are significantly attenuated.ConclusionDirect quantification of periodic caudal brain tissue displacement is feasible with the proposed method, and several brain regions can be distinguished through peak displacement and time‐to‐peak values. J. Magn. Reson. Imaging 2007. © 2007 Wiley‐Liss, Inc.
Krylov model order reduction of finite element approximations of electromagnetic devices with frequency‐dependent material properties
Authors: Wu Hong , Cangellaris Andreas C. 
Published: March 2007

AbstractA methodology is presented for the Krylov subspace‐based model order reduction of finite element models of electromagnetic structures with material properties and impedance boundary conditions exhibiting arbitrary frequency dependence. The proposed methodology is a generalization of an equation‐preserving Krylov model order reduction scheme for methodology for second‐order, linear dynamical systems. The emphasis of this paper is on the application of this method to the broadband model order reduction of planar circuits including lossy strips of arbitrary thickness and lossy reference planes. In particular, it is shown that the proposed model order reduction methodology provides for the accurately modelling of the impact of the frequency dependence of the internal impedance per unit length of the thick lossy strip on the electromagnetic response of the stripline structure over a very broad, multi‐GHz frequency band, extending all the way down to frequencies in the DC neighbourhood. In addition, the application of the proposed methodology to the broadband modelling of electromagnetic coupling between strips on either side of a lossy ground plane is demonstrated. Copyright © 2007 John Wiley & Sons, Ltd.
Interplay of leukemia inhibitory factor and retinoic acid on neural differentiation of mouse embryonic stem cells
Authors: Martín‐Ibáñez Raquel , Urbán Noelia , Sergent‐Tanguy Solène , Pineda José Ramón , Garrido‐Clua Núria , Alberch Jordi , Canals Josep M. 
Published: March 2007

AbstractEmbryonic stem (ES) cells have great potential for cell replacement in neurodegenerative disorders. Implantation of these cells into the brain, however, requires their prior differentiation. We examined the interplay between leukemia inhibitory factor (LIF) and retinoic acid (RA) on neural differentiation of mouse ES (mES) cells. Mouse embryonic stem cells were allowed to form cell aggregates, the so‐called embryoid bodies (EBs), in the absence or presence of LIF. In the absence of LIF, mES cells downregulated the expression of the undifferentiated mES cell marker Oct‐3/4, and increased mRNA levels of two neural precursor markers, Sox‐1 and Nestin, as well as the neuronal marker β‐tubulin III. This neuronal differentiation was enhanced by treating EBs with RA. Moreover, RA irreversibly increased the number of postmitotic neurons in culture, as shown by the reduction of proliferating mES cells and the increase in β‐tubulin III‐positive cells 6 days after RA removal, which in turn affected mES cell viability. The addition of LIF during EBs formation, however, blocked completely this neuronal differentiation. Our findings also showed that pre‐differentiation of mES cells in vitro avoided the teratocarcinoma formation observed when proliferating mES cells were grafted into the brain. In addition, mES cells pre‐differentiated with RA in culture showed a reduction in proliferation and the presence of neural phenotypes after grafting. In conclusion, the present results indicate that RA enhances neuronal differentiation of mES cells in the absence of LIF, although it compromises cell viability and transplantation. © 2007 Wiley‐Liss, Inc.
NO‐induced downregulation of HSP10 and HSP60 expression in the postischemic brain
Authors: Kim Seung‐Woo , Lee Ja‐Kyeong 
Published: March 2007

AbstractHeat shock protein 60 (HSP60) and HSP10 are mitochondrial chaperonin proteins and are responsible for the folding of newly imported proteins and 13 polypeptides encoded by mitochondrial DNA. The expressions of HSP60 and HSP10 are regulated simultaneously because these genes are localized head to head on chromosome, separated by a bidirectional promoter, which harbors heat shock element (HSE), CHOP, STAT3, and SP1 binding sites. In the present study, we show that the expressions of HSP60 and HSP10 in the brain after middle cerebral artery occlusion (MCAO) are induced significantly. Interestingly, the expressions of HSP60 and HSP10 were further upregulated by the administration of aminoguanidine (AG), an inhibitor of the inducible nitric oxide synthase (iNOS), which is known to reduce ischemic damage in an animal model after MCAO. The results obtained in the present study suggest that HSP10 and HSP60 are induced in the postischemic brain, yet are downregulated by NO generated from 12 hr after MCAO/reperfusion. The downregulation of HSP60 and HSP10 by NO were confirmed in vitro, wherein HSP10 and SHP60 expressions were increased by treatment of LPS and IFNγ (LPS/INFγ) in C6 astroglioma cells and further upregulated by NMMA, another iNOS inhibitor. Reporter gene analysis combined with deletion and mutation studies showed that STAT3 binding site in the bidirectional promoter is responsible for LPS/INFγ‐induced upregulation and for downregulation by NO. Our results indicated that NO suppresses HSP60 and HSP10 inductions in the postischemic brain by suppressing STAT3 binding to its recognition site. © 2007 Wiley‐Liss, Inc.
Estimation of the mechanical property of meniscus using ultrasound: Examinations of native meniscus and effects of enzymatic digestion
Authors: Yasura Ko , Mizuno Yasuyuki , Nakagawa Yasuaki , Mori Koji , Takenaka Makoto , Ohashi Tetsuo , Yamada Keisuke , Kobayashi Masahiko , Ando Keiji , Kuroki Hiroshi , Suzuki Takashi , Ikeuchi Ken , Tsutsumi Sadami , Nakamura Takashi 
Published: March 2007

AbstractWe previously developed a novel ultrasound assessment system featuring wavelet transform to evaluate the material properties of articular cartilage. We aimed in this study to demonstrate the feasibility of quantitative evaluation of meniscus using ultrasound and to elucidate the relationships between its acoustic, mechanical, and biochemical properties. Meniscal disc specimens from mature pigs were assessed by ultrasound and compression testing, and their correlation was analyzed. A positive correlation was found between the ultrasound signal intensity and apparent Young's modulus (r = 0.61). Subsequently, the porcine meniscal discs were treated with various enzymes and then characterized by ultrasound, by compression tests, by biochemical analyses, and by histology and immunohistochemistry. The signal intensity was decreased not by hyaluronidase but by collagenase treatment. Hyaluronidase‐treated menisci showed a discrepancy between acoustic and mechanical properties, suggesting that the ultrasound reflection could not detect a reduction in proteoglycan content. Also, ultrasound signal intensity could only reflect superficial layers of the material. Several limitations exist at present, and further studies and improvements of the device are required. However, given the noninvasive nature and the requirement of only small equipment, this ultrasound assessment system will be an instrumental diagnostic tool for meniscal function in both research and clinical fields. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:884–893, 2007
Cartilaginous deposits in subchondral bone in regions of exposed bone in osteoarthritis of the human knee: Histomorphometric study of PRG4 distribution in osteoarthritic cartilage
Authors: Zhang Dong , Johnson Lanny J. , Hsu Hu‐Ping , Spector Myron 
Published: March 2007

AbstractThe objective of this study was to identify and characterize cartilaginous deposits aggregates in the subchondral bone in areas of the human osteoarthritic knee with exposed bone. A specific aim was to determine the distribution of the joint lubrication molecule, lubricin/superficial zone protein [referred to by its gene, proteoglycan4 (PRG4)], in these cartilaginous deposits and in osteoarthritic cartilage. This work was carried out in the context of assessing the potential contribution of these chondrocyte aggregates for joint resurfacing in certain cartilage repair procedures. The discarded bone cuts of femoral condyles and tibial plateaus were collected from 11 patients with advanced osteoarthritis (OA) of the knee during total knee arthroplasty; 9 women and 2 men with a mean age of 68 years. Sections of paraffin‐embedded tissue were stained with Safranin‐O, and with antibodies to type II collagen, α‐smooth muscle actin (SMA), and PRG4. Chondrocyte aggregates were found in the subchondral bone of regions of exposed bone in sections from five individuals. The average diameter of cartilaginous aggregates was 152 µm, and the average depth of the aggregates below the surface was about 475 µm. Most aggregates were fibrocartilaginous and stained positive for type II collagen. Of interest was the finding that the cartilaginous deposits and osteoarthritic cartilage contained PRG4. Only a small percentage of chondrocytes stained positive for SMA. Cartilaginous deposits containing chondrocyte aggregates exist in subchondral bone in regions of exposed bone in some patients with advanced OA of the knee. These cells may be able to contribute to the resurfacing of the joint in certain cartilage repair procedures. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:873–883, 2007