bluuebunny/crossref_metadata_2025_split huggingface dataset:
Molecular imaging of microglia/macrophages in the brain
Authors: Venneti Sriram , Lopresti Brian J. , Wiley Clayton A. 
Published: May 2012

AbstractNeuroinflammation perpetuates neuronal damage in many neurological disorders. Activation of resident microglia and infiltration of monocytes/macrophages contributes to neuronal injury and synaptic damage. Noninvasive imaging of these cells in vivo provides a means to monitor progression of disease as well as assess efficacies of potential therapeutics. This review provides an overview of positron emission tomography (PET) and magnetic resonance (MR) imaging of microglia/macrophages in the brain. We describe the rationale behind PET imaging of microglia/macrophages with ligands that bind to translocator protein‐18 kDa (TSPO). We discuss the prototype TSPO radioligand [11C]PK11195, its limitations, and the development of newer TSPO ligands as PET imaging agents. PET imaging agents for targets other than TSPO are emerging, and we outline the potential of these agents for imaging brain microglia/macrophage activity in vivo. Finally, we briefly summarize advances in MR imaging of microglia/macrophages using iron oxide nanoparticles and ultra‐small super paramagnetic particles that are phagocytosed. Despite many technical advances, more sensitive agents are required to be useful indicators of neuroinflammation in brain. © 2012 Wiley Periodicals, Inc.
New phosphorus‐containing quinone derivatives
Authors: Müller Patrick , Bykov Yana , Walter Olaf , Döring Manfred 
Published: May 2012

AbstractA variety of new aromatic diols substituted with two (similar and different) phosphorus groups were synthesized via the Michael‐type addition of a PH bond containing reagents to p‐benzoquinone, reoxidation and the subsequent addition of a second phosphorus unit. In all studied cases, 2,3‐substituted products were obtained exclusively. The resulting hydroquinone derivatives were further investigated regarding rearrangements under basic conditions. © 2012 Wiley Periodicals, Inc. Heteroatom Chem 23:383–394, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/hc.21028
Spatial and temporal variations in rainfall characteristics in mountainous and lowland areas in Taiwan
Authors: Kao Shih‐Chun , Kume Tomonori , Komatsu Hikaru , Liang Wei‐Li 
Published: May 2012

AbstractAlthough changes in rainfall characteristics have been noted across the world, few studies have reported those in mountainous areas. This study was undertaken to clarify spatial and temporal variations in rainfall characteristics such as annual rainfall amount (Pr), mean daily rainfall intensity (η), and ratio of rain days (λ) in mountainous and lowland areas in Taiwan. To this aim, we examined spatial and year‐to‐year variations and marginal long‐term trends in Pr, η, and λ, based on rainfall data from 120 stations during the period 1978–2008. The period mean rainfall () at the lowland stations had strong relationships with the period mean daily rainfall intensity () and the period mean ratio of rain days () during those 31 years. Meanwhile, was only strongly related to at mountainous stations, indicating that influences on spatial variations in were different between lowland and mountainous stations. Year‐to‐year variations in Pr at each station were primarily determined from the variation in η at most stations for both lowland and mountainous stations. Long‐term trend analysis showed that Pr and η increased significantly at 10% and 31% of the total 120 stations, respectively, and λ decreased significantly at 6% of the total. The increases in Pr were mostly accompanied by increases in η. Although stations with significant η increases were slightly biased toward the western lowland area, increases or decreases in Pr and λ were not common. These results contribute to understanding the impacts of possible climate changes on terrestrial hydrological cycles. Copyright © 2012 John Wiley & Sons, Ltd.
Directing epithelial to mesenchymal transition through engineered microenvironments displaying orthogonal adhesive and mechanical cues
Authors: Markowski Marilyn C. , Brown Ashley C. , Barker Thomas H. 
Published: May 2012

AbstractCell interactions with their extracellular matrix (ECM) microenvironments play a major role in directing cellular processes that can drive wound healing and tissue regeneration but, if uncontrolled, lead to pathological progression. One such process, epithelial to mesenchymal transition (EMT), if finely controlled could have significant potential in regenerative medicine approaches. Despite recent findings that highlight the influence of biochemical and mechanical properties of the ECM on EMT, it is still unclear how these two orthogonal cues act synergistically to control epithelial cell phenotype. Here, we cultured lung epithelial cells on combinations of different mutants of fibronectin's cell binding domain that preferentially engage specific integrins and substrates of varying stiffness. Our results suggest that while stiff substrates induce spontaneous EMT, this response can be overcome by with fragments of fibronectin that support α3 and α5 integrin engagement. Furthermore, we found that substrate‐induced EMT correlates with transforming growth factor beta activation by resident epithelial cells and is dependent on Rho/ROCK signaling. Suppressing cell‐contractility was sufficient to maintain an epithelial phenotype. Our results suggest that integrin‐specific engagement of fibronectin adhesive domains and the mechanics of the ECM act synergistically to direct EMT. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2012.
Effects of microrough and hierarchical hybrid micro/nanorough surface implants on osseointegration in ovariectomized rats: A longitudinal in vivo microcomputed tomography evaluation
Authors: Gao Yuan , Li Yongfeng , Xiao Jianrui , Xu Lixian , Hu Kaijin , Kong Liang 
Published: May 2012

AbstractThis study aimed to evaluate the effects of microrough and hierarchical hybrid micro/nanorough surface implants on osseointegration in ovariectomized rats at different time points. Implants with machined, microrough and hierarchical hybrid micro/nanorough surfaces were inserted into the distal femurs of ovariectomized Sprague‐Dawley female rats. At weeks 0, 4, and 12 following implantation, in vivo microcomputed tomography (micro‐CT) scanning was used to assess bone microarchitectural changes. After 12 weeks, all the rats were sacrificed, and the femurs with implants were harvested for histological analysis and pull‐out test. For the Micro‐CT analysis, the trabecular number and the bone volume ratio increased significantly in the microrough group (p < 0.01) and micro/nanorough group (p < 0.01) compared with the machined group. The trabecular separation decreased significantly in the micro/nanorough group (p < 0.01) compared with the other two groups. For the maximum pull‐out forces and the bone–implant‐contact analyses, significant statistical differences were found among the three groups, with the following sequence: micro/nanorough group > microrough group > machined group. The results indicate that the microrough and the hierarchical hybrid micro/nanorough surfaces of the implant can be beneficial to osseointegration under osteoporotic conditions, and the hierarchical hybrid micro/nanorough surface is more efficient. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2012.
Adhesion of MC3T3‐E1 cells bound to dentin phosphoprotein specifically bound to collagen type I
Authors: Zurick Kevin M. , Qin Chunlin , Bernards Matthew T. 
Published: May 2012

AbstractDentin sialophosphoprotein (DSPP) is a member of the SIBLING (small integrin binding N‐linked glycoprotein) family of proteins commonly found in mineralized tissues. Dentin phosphoprotein (DPP) is a naturally occurring subdomain of DSPP that contains the cell binding RGD sequence. Previously, the orientation and conformation of other SIBLING family members specifically bound to collagen I have been investigated with respect to their cell adhesion properties. In this study, the orientation of DPP under similar circumstances is examined, and the results are discussed relative to the previous investigations. Radiolabeled adsorption isotherms were developed for DPP adsorbing to both tissue culture polystyrene (TCPS) and collagen coated TCPS. Then, a MC3T3‐E1 cell adhesion assay was performed on TCPS and collagen coated TCPS in the presence of identical amounts of adsorbed DPP. It was discovered that there was a significant difference in the number of bound cells on the TCPS and collagen coated TCPS, with a preference for TCPS. Furthermore, a cell inhibition assay was conducted to confirm that the cell binding that occurred was due to specific integrin interactions with the RGD sequence of DPP. These results suggest that the orientation of DPP, rather than its conformation, dictates the accessibility of the cell binding RGD domains of DPP and that the RGD sequence in DPP is less accessible when DPP is specifically bound to collagen. The results obtained in this study are in stark contrast to previous studies with related SIBLING proteins, and suggest that DPP does not play a key role in cell binding to the collagen matrix of developing bone. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 100A: 2492–2498, 2012.
Evaluation of Jeffamine®‐cored PAMAM dendrimers as an efficient in vitro gene delivery system
Authors: Aydin Zeynep , Akbas Fahri , Senel Mehmet , Koc S. Naci 
Published: May 2012

AbstractIn this study, we investigated gene delivery properties of Jeffamine‐cored polyamidoamine (PAMAM) dendrimers (JCPDs). The effects of dendrimer concentration, generation, and core size on the gene delivery have been analyzed. The experimental results showed that the JCPD effectively delivered plasmid DNA inside the HeLa cells, and the transfection efficiency improved considerably as the number of generation increased. The cytotoxicity of JCPD in different concentration was tested for HeLa cell line. JCPD was complexed with a lacZ gene carrying plasmid and tested for transfection efficiency using quantitative β‐galactosidase expression assay. Additionally, confocal microscopy results revealed that JCPD effectively delivered green fluorescent protein‐expressing plasmid into HeLa cells and produced fluorescent signal with satisfactory efficiency. The highest transfection efficiency was obtained from JCPDs G4 and G5, which mixed with expression plasmid vectors at a 10/1 weight ratio. These results indicated that under optimized conditions, JCPD can be considered as an efficient transfection reagent and can be effectively used for gene delivery applications. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A 100A:2623–2628, 2012.
Calcification resistance for photooxidatively crosslinked acellular bovine jugular vein conduits in right‐side heart implantation
Authors: Lü Wei‐Dong , Wang An‐Ping , Wu Zhong‐Shi , Zhang Ming , Hu Tie‐Hui , Lei Guang‐Yan , Hu Ye‐Rong 
Published: May 2012

AbstractThis study aimed to investigate the effect of decellularization plus photooxidative crosslinking and ethanol pretreatment on bioprosthetic tissue calcification. Photooxidatively crosslinked acellular (PCA) bovine jugular vein conduits (BJVCs) and their photooxidized controls (n = 5 each) were sterilized in a graded concentration of ethanol solutions for 4 h, and used to reconstruct dog right ventricular outflow tracts. At 1‐year implantation, echocardiography showed similar hemodynamic performance, but obvious calcification for the photooxidized BJVC walls. Further histological examination showed intense calcium deposition colocalized with slightly degraded elastic fibers in the photooxidized BJVC walls, with sparsely distributed punctate calcification in the valves and other areas of walls. But PCA BJVCs had apparent degradation of elastic fibers in the walls, with only sparsely distributed punctate calcification in the walls and valves. Content assay demonstrated comparable calcium content for the two groups at preimplantation, whereas less calcium for the PCA group in the walls and similar calcium in the valvular leaflets compared with the photooxidized group at 1‐year retrieval. Elastin content assay presented the conduit walls of PCA group had less elastin content at preimplantation, but similar content at 1‐year retrieval compared with the photooxidized group. Phospholipid analysis showed phospholipid extraction by ethanol for the PCA group was more efficacious than the photooxidized group. These results indicate that PCA BJVCs resist calcification in right‐side heart implantation owing to decellularization, further photooxidative crosslinking, and subsequent phospholipid extraction by ethanol at preimplantation. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A 100A:2644–2653, 2012.
Bioactive glass/polymer composite scaffolds mimicking bone tissue
Authors: Gentile Piergiorgio , Mattioli‐Belmonte Monica , Chiono Valeria , Ferretti Concetta , Baino Francesco , Tonda‐Turo Chiara , Vitale‐Brovarone Chiara , Pashkuleva Iva , Reis Rui L. , Ciardelli Gianluca 
Published: May 2012

AbstractThe aim of this work was the preparation and characterization of scaffolds with mechanical and functional properties able to regenerate bone. Porous scaffolds made of chitosan/gelatin (POL) blends containing different amounts of a bioactive glass (CEL2), as inorganic material stimulating biomineralization, were fabricated by freeze‐drying. Foams with different compositions (CEL2/POL 0/100; 40/60; 70/30 wt %/wt) were prepared. Samples were crosslinked using genipin (GP) to improve mechanical strength and thermal stability. The scaffolds were characterized in terms of their stability in water, chemical structure, morphology, bioactivity, and mechanical behavior. Moreover, MG63 osteoblast‐like cells and periosteal‐derived stem cells were used to assess their biocompatibility. CEL2/POL samples showed interconnected pores having an average diameter ranging from 179 ± 5 μm for CEL2/POL 0/100 to 136 ± 5 μm for CEL2/POL 70/30. GP‐crosslinking and the increase of CEL2 amount stabilized the composites to water solution (shown by swelling tests). In addition, the SBF soaking experiment showed a good bioactivity of the scaffold with 30 and 70 wt % CEL2. The compressive modulus increased by increasing CEL2 amount up to 2.1 ± 0.1 MPa for CEL2/POL 70/30. Dynamical mechanical analysis has evidenced that composite scaffolds at low frequencies showed an increase of storage and loss modulus with increasing frequency; furthermore, a drop of E′ and E″ at 1 Hz was observed, and for higher frequencies both moduli increased again. Cells displayed a good ability to interact with the different tested scaffolds which did not modify cell metabolic activity at the analyzed points. MTT test proved only a slight difference between the two cytotypes analyzed. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A 100A:2654–2667, 2012.
Cardiopulmonary hemodynamic responses to the small injection of hemoglobin vesicles (artificial oxygen carriers) in miniature pigs
Authors: Sakai Hiromi , Suzuki Yuji , Sou Keitaro , Kano Mayumi 
Published: May 2012

AbstractIntravenous injection of liposomes into pigs reportedly induces anaphylactoid reactions at a small dose, resulting in circulatory disorder. Hemoglobin vesicles (HbVs) are artificial oxygen carriers encapsulating Hb solution in liposomes. It is not known how pigs respond to HbV injection. We aimed to analyze the cardiopulmonary responses to small injections of HbV and empty vesicle (EV) and compare them with a conventional liposome (CL) with a different lipid composition containing phosphatidylglycerol (PG). PG is known to induce an anaphylactoid reaction in pigs. Nine male miniature pigs were used for HbV, EV, and CL injections. The anesthetized pig received 0.05 and 0.5 mL/kg of a test fluid for the first and second injection with a 70 min interval. Results show that CL repeatedly induced significant increases in systemic and pulmonary arterial pressures and vascular resistances and decreases in heart rate and cardiac output (CO). HbV and EV at the first injection‐induced pulmonary hypertension, with significantly smaller changes in systemic arterial pressure and CO. No remarkable response was visible at the second injection in spite of a larger dosage. Only CL repeatedly induced thrombocytopenia, leukocytopenia, and plasma thromboxane B2 increase resulting from complement activation, although HbV and EV showed smaller changes. Transmittance electron micrograph of pulmonary intravascular macrophages (PIMs) showed phagocytosis of HbV, indicating the possibility that nonspecific phagocytosis by PIMs relates to the responses observed after the first injection. HbV does not induce a significant anaphylactoid reaction in pigs compared with CL because of the different lipid composition. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A 100A:2668–2677, 2012.
Uniaxial mechanical tension promoted osteogenic differentiation of rat tendon‐derived stem cells (rTDSCs) via the Wnt5a‐RhoA pathway
Authors: Shi Yu , Fu Yujie , Tong Wenxue , Geng Yiyun , Lui Pauline Po Yee , Tang Tingting , Zhang Xiaoling , Dai Kerong 
Published: May 2012

AbstractChronic tendinopathy is a tendon disorder that is common in athletes and individuals whose tendons are subjected to repetitive strain injuries. The presence of ossification worsened the clinical manifestation of the disorder. The change of tendon loading due to mechanical overload, compression, or disuse have been implicated as the possible etiologies, but the pathological mechanisms of tendinopathy remain unclear. In this study, we demonstrated that ossification in tendon tissue might be due to the osteogenesis of tendon‐derived stem cells (TDSCs) induced by uniaxial mechanical tension (UMT) which mimics the mechanical loading in tendon. Rat TDSCs (rTDSCs) could be induced to differentiate into osteogenic lineage after treatment with 2% elongation UMT for 3 days as shown by the increased expression Runx2 mRNA and protein, Alpl mRNA, collagen type 1 alpha 1 (Col1a1) mRNA, ALP activity, and ALP cytochemical staining. RhoA, an osteogenesis regulator, was activated in rTDSCs upon UMT stimulation. Blockage of RhoA activity in rTDSCs by C3 toxin or ROCK activity, a downstream target of RhoA, by Y‐27632 inhibited UMT‐induced osteogenesis in rTDSCs. UMT up‐regulated the mRNA expression of Wnt5a but not the other non‐canonical Wnts. The inhibition of Wnt5a expression by siRNA abolished UMT‐induced Runx2 mRNA expression and RhoA activation in rTDSCs and the inhibition of Runx2 expression could be rescued by addition of LPA, a RhoA activator. In conclusion, our results showed that UMT induced osteogenic differentiation of rTDSCs via the Wnt5a‐RhoA pathway, which might contribute to ectopic ossification in tendon tissue due to mechanical loading. J. Cell. Biochem. 113: 3133–3142, 2012. © 2012 Wiley Periodicals, Inc.
Impaired biomechanical properties correlate with neoangiogenesis as well as VEGF and MMP‐3 expression during rat patellar tendon healing
Authors: Sahin Hacer , Tholema Nancy , Petersen Wolf , Raschke Michael J. , Stange Richard 
Published: May 2012

AbstractRecent studies reveal an important role of vascular endothelial growth factor (VEGF)‐induced angiogenesis in degenerative tendon diseases. The way how VEGF influences mechanical properties of the tendons is not well understood yet. We here hypothesized that tendinopathy results in a hypoxia‐mediated stimulation of VEGF and that the mechanical stability of the tendon is impaired in an angiogenic process by VEGF‐induced matrix metalloproteinases (MMPs). A modified in situ freezing model of patellar tendon was used to create a tendinopathy. 0, 7, 14, and 28 days post‐surgical animals were sacrificed and patellar tendons were dissected for biomechanical and immunohistochemical analysis. Native tendons were used as controls. Immunohistochemical staining revealed a peak in HIF‐1α stabilization immediately after surgery. Both VEGF and MMP‐3 were increased 7 days after surgery. Angiogenesis was also abundant 7 days after surgery. In contrast, biomechanical stability of the tendon was decreased 7 days after surgery. The current results reveal a time‐dependent correlation of HIF‐1/VEGF‐induced and MMP‐3‐supported angiogenesis with decreased biomechanical properties during tendon healing. The therapeutical modulation of neoangiogenesis by influencing the level of VEGF and MMP‐3 might be a promising target for new approaches in degenerative tendon diseases. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 30:1952–1957, 2012
E‐cadherin upregulates expression of matrix macromolecules aggrecan and collagen II in the intervertebral disc cells through activation of the intracellular BMP‐Smad1/5 pathway
Authors: Wang Zili , Kim Sung Soo , Hutton William C. , Yoon Sangwook Tim 
Published: May 2012

AbstractE‐cadherin is a transmembrane protein that mediates cell–cell adhesion and cell–matrix interaction. Although the E‐cadherin has been shown to mediate a broad‐ranging cellular signals and functions, its effects on matrix metabolism of intervertebral discs (IVDs) are unknown. In this study, we investigated the effects of E‐cadherin on IVD matrix synthesis using pharmacological and molecular biology methods. We showed that high levels of the E‐cadherin are expressed in rabbits IVD cells. Our study indicates that the ectopic expression of E‐cadherin can stimulate matrix anabolism of the IVD cells, which was evidenced by increased expression of the matrix macromolecules aggrecan and collagen II. We found that E‐cadherin induces the expression of BMP‐4 and BMP‐7 genes and enhances Smad1/5 phosphorylation. Blocking BMP activity uses noggin suppressed E‐cadherin‐mediated upregulation of aggrecan and collagen II. Moreover, inhibition of Smad1/5 phosphorylation by dorsomorphin significantly repressed the E‐cadherin induced expression of aggrecan and collagen II at the both mRNA and protein levels. Together this study demonstrates that the E‐cadherin stimulates the synthesis of IVD matrix macromolecules aggrecan and collagen II through the induction of BMP genes and enhancement of the Smad1/5 phosphorylation. Thus E‐cadherin may have value in the treatment of degenerated discs. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 30:1746–1752, 2012
Optimism predicts resilience in repatriated prisoners of war: A 37‐year longitudinal study
Authors: Segovia Francine , Moore Jeffrey L. , Linnville Steven E. , Hoyt Robert E. , Hain Robert E. 
Published: May 2012

AbstractResilience, exhibiting intact psychological functioning despite exposure to trauma, is one perspective as to why some people who are exposed to trauma do not develop symptoms. This study examines the prisoner of war experience to expand our understanding of this phenomenon in extreme cases of trauma such as prolonged captivity, malnourishment, and physical and psychological torture. The study examined the United States' longest detained American prisoners of war, those held in Vietnam in the 1960s through early 1970s. A logistic regression analysis using resilience, defined as never receiving any psychiatric diagnosis over a 37‐year follow‐up period, as the outcome was performed (n = 224 with complete data). Six variables showing at least small effects emerged: officer/enlisted status, age at time of capture, length of solitary confinement, low antisocial/psychopathic personality traits, low posttraumatic stress symptoms following repatriation, and optimism. Odds ratios (ORs) and confidence intervals (CIs) confirmed the significance and relative strength of these variables, with a range from OR = 0.54, 95% CI [0.13, 2.29] to OR = 1.11, 95% CI [1.04, 1.17]. When all variables were examined continuously and categorically, dispositional optimism was the strongest variable, accounting for 17%, continuously, and 14%, categorically. We discuss optimism as a protective factor for confronting trauma and the possibility of training to increase it.