bluuebunny/crossref_metadata_2025_split huggingface dataset:
Binding of human coronary artery endothelial cells to plasma‐treated titanium dioxide nanotubes of different diameters
Authors: Flašker Ajda , Kulkarni Mukta , Mrak‐Poljšak Katjuša , Junkar Ita , Čučnik Saša , Žigon Polona , Mazare Anca , Schmuki Patrik , Iglič Aleš , Sodin‐Semrl Snezna 
Published: January 2016

AbstractNanoscale topography in improving vascular response in vitro was established previously on various titanium surfaces. In the present study different surface nanotopographies that is different diameters of titanium dioxide (TiO2) nanotubes (NTs) were fabricated by electrochemical anodization and conditioned with highly reactive gaseous oxygen plasma. The morphology of different diameter NTs was studied by scanning electron microscopy and atomic force microscopy, while changes in chemical composition on the surface before and after plasma treatment were determined by X‐ray photoelectron spectroscopy. Performance of human coronary artery endothelial cells (HCAEC) on those conditioned surfaces was studied in regard to cell proliferation, released IL‐6 protein and immunofluorescence microscopy (IFM). We show that HCAEC function is dependent on the diameter of the TiO2 NTs, functioning far less optimally when bound to 100 nm TiO2 NTs as compared to Ti foil, 15 nm NTs or 50 nm NTs. There were improved, morphological cell shape changes, observed with IFM, between HCAEC growing on oxygen‐rich plasma‐treated versus nontreated 100 nm NTs. These endothelialized conditioned Ti nanosurfaces could elucidate optimization conditions necessary for vascular implants in coronary arteries. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1113–1120, 2016.
Enhanced osteogenic differentiation of MC3T3‐E1 cells on grid‐topographic surface and evidence for involvement of YAP mediator
Authors: Zhang Yingying , Gong He , Sun Yan , Huang Yan , Fan Yubo 
Published: January 2016

AbstractNumerous studies have shown that surface topography can promote cell–substrate associations and deeply influence cell fate. The intracellular mechanism or how micro‐ or nano‐patterned extracellular signal is ultimately linked to activity of nuclear transcription factors remains unknown. It has been reported that Yes‐associated protein (YAP) can respond to extracellular matrix microenvironment signals, thus regulates stem cell differentiation process. We propose that YAP may play a role in mediating the topography induced cell differentiation. To this end, we fabricated polydimethylsiloxane (PDMS) micropatterns with grid topology (GT) (3 μm pattern width, 2 μm pattern interval length, 7 μm pattern height); nonpatterned PDMS substrates were used as the planar controls. The MC3T3‐E1 cells were then cultured on these surfaces, respectively, in osteogenic inducing medium. Cell differentiation in terms of osteogenesis related gene expression, protein levels, alkaline phosphatase activity and extracellular matrix mineralization was assessed. It was shown that the cells on GT surfaces had stronger osteogenesis capacity. In addition, expression level of YAP was increased when MC3T3‐E1 cells grew on GT substrates, which was similar to the levels of osteogenic differentiation markers. It was also shown that YAP knockdown attenuated GT substrates‐induced MC3T3‐E1 differentiation, which reduced the osteogenic differentiation effect of the GT substrates. Collectively, our findings indicate that GT substrates‐induced MC3T3‐E1 differentiation may be associated with YAP. This paper provides new target points for transcriptional mechanism research of microenvironment induced cell differentiation and a useful approach to obtain more biofunctionalization scaffolds for tissue engineering. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1143–1152, 2016.
Fabrication of intrafibrillar and extrafibrillar mineralized collagen/apatite scaffolds with a hierarchical structure
Authors: Hu Changmin , Zilm Michael , Wei Mei 
Published: January 2016

AbstractA biomimetic collagen‐apatite (Col‐Ap) scaffold resembling the composition and structure of natural bone from the nanoscale to the macroscale has been successfully prepared for bone tissue engineering. We have developed a bottom‐up approach to fabricate hierarchically biomimetic Col‐Ap scaffolds with both intrafibrillar and extrafibrillar mineralization. To achieve intrafibrillar mineralization, polyacrylic acid (PAA) was used as a sequestrating analog of noncollagenous proteins (NCPs) to form a fluidic amorphous calcium phosphate (ACP) nanoprecursor through attraction of calcium and phosphate ions. Sodium tripolyphosphate was used as a templating analog to regulate orderly deposition of apatite within collagen fibrils. Both X‐ray diffraction and Fourier transform infrared spectroscopy suggest that the mineral phase was apatite. Field emission scanning electron microscopy, transmission electron microscopy, and selected area electron diffraction confirmed that hierarchical collagen‐Ap scaffolds were produced with both intrafibrillar and extrafibrillar mineralization. Biomimetic Col‐Ap scaffolds with both intrafibrillar and extrafibrillar mineralization (IE‐Col‐Ap) were compared with Col‐Ap scaffolds with extrafibrillar mineralization only (E‐Col‐Ap) as well as pure collagen scaffolds in vitro for cellular proliferation using MC3T3‐E1 cells. Pure collagen scaffolds had the highest rate of proliferation, while there was no statistically significant difference between IE‐Col‐Ap and E‐Col‐Ap scaffolds. Thus, the bottom‐up biomimetic fabrication approach has rendered a group of promising Col‐Ap scaffolds, which bear high resemblance to natural bone in terms of composition and structure. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1153–1161, 2016.
Saos‐2 cell‐mediated mineralization on collagen gels: Effect of densification and bioglass incorporation
Authors: Liu Gengbo , Pastakia Meet , Fenn Michael B. , Kishore Vipuil 
Published: January 2016

AbstractPlastic compression is a collagen densification process that has been widely used for the development of mechanically robust collagen‐based materials. Incorporation of bioglass within plastically compressed collagen gels has been shown to mimic the microstructural properties of native bone and enhance in vitro cell‐mediated mineralization. The current study seeks to decouple the effects of collagen densification and bioglass incorporation to understand the interplay between collagen packing density and presence of bioglass on cell‐mediated mineralization. Saos‐2 cell‐mediated mineralization was assessed as a measure of the osteoconductivity of four different collagen gels: (1) uncompressed collagen gel (UC), (2) bioglass incorporated uncompressed collagen gel (UC + BG), (3) plastically compressed collagen gel (PC), and (4) bioglass incorporated plastically compressed collagen gel (PC + BG). The results indicated that collagen densification enhanced mineralization as shown by SEM, increased alkaline phosphatase activity and produced significantly higher amounts of mineralized nodules on PC gels compared to UC gels. Further, the amount of nodule formation on PC gels was significantly higher compared to UC + BG gels indicating that increase in matrix stiffness due to collagen densification had a greater effect on cell‐mediated mineralization compared to bioglass incorporation into loosely packed UC gels. Incorporation of bioglass into PC gels further enhanced mineralization as evidenced by significantly larger nodule size and higher amount of mineralization on PC + BG gels compared to PC gels. In conclusion, collagen densification via plastic compression improves the osteoconductivity of collagen gels. Further, incorporation of bioglass within PC gels has an additive effect and further enhances the osteoconductivity of collagen gels. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1121–1134, 2016.
Effect of carbodiimide‐derivatized hyaluronic acid gelatin on preventing postsurgical intra‐abdominal adhesion formation and promoting healing in a rat model
Authors: Yuan Fang , Lin Long‐Xiang , Zhang Hui‐Hui , Huang Dan , Sun Yu‐Long 
Published: January 2016

AbstractAdhesions often occur after abdominal surgery. It could cause chronic pelvic pain, intestinal obstruction, and infertility. A hydrogel biomaterial, carbodiimide‐derivatized hyaluronic acid gelatin (cd‐HA gelatin), has been successfully used to reduce adhesion formation after flexor tendon grafting. This study investigated the efficacy of cd‐HA gelatin in preventing postsurgical peritoneal adhesions in a rat model. The surgical traumas were created on the underlying muscle of the abdominal wall and the serosal layer of the cecum. The wounds were covered with or without cd‐HA gelatin. Animals were euthanized at day 14 after surgery. Adhesion formation was assessed with adhesion degree and adhesion breaking strength. The healing of abdominal wall was evaluated with biomechanical testing and histological analysis. The adhesions occurred in all rats (n = 12) without cd‐HA gelatin treatment. The application of cd‐HA gelatin significantly reduced the adhesion rate from 100% to 58%. The decrease of adhesion breaking strength also manifested that cd‐HA gelatin could reduce postsurgical intra‐abdominal adhesion formation. Moreover, it was found that cd‐HA gelatin was a safe material and could promote tissue healing. The cd‐HA gelatin hydrogel could reduce the formation of intra‐abdominal adhesions without adversely effects on wound healing. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1175–1181, 2016.
Parathyroid Hormone and the Use of Diuretics and Calcium-Channel Blockers: The Multi-Ethnic Study of Atherosclerosis
Authors: Zaheer Sarah , de Boer Ian , Allison Matthew , Brown Jenifer M , Psaty Bruce M , Robinson-Cohen Cassianne , Ix Joachim H , Kestenbaum Bryan , Siscovick David , Vaidya Anand 
Published: January 2016

ABSTRACT

Thiazide diuretic (TZ) use is associated with higher bone mineral density, whereas loop diuretic (LD) use is associated with lower bone density and incident fracture. Dihydropyridine-sensitive calcium channels are expressed on parathyroid cells and may play a role in parathyroid hormone (PTH) regulation. The potential for diuretics and calcium-channel blockers (CCBs) to modulate PTH and calcium homeostasis may represent a mechanism by which they influence skeletal outcomes. We hypothesized that the use of LD and dihydropyridine CCBs is associated with higher PTH, and TZ use is associated with lower PTH. We conducted cross-sectional analyses of participants treated for hypertension in the Multi-Ethnic Study of Atherosclerosis who did not have primary hyperparathyroidism or chronic kidney disease (n = 1888). We used adjusted regression models to evaluate the independent association between TZ, LD, and CCB medication classes and PTH. TZ use was associated with lower PTH when compared with non-TZ use (44.4 versus 46.9 pg/mL, p = 0.02), whereas the use of LD and CCBs was associated with higher PTH when compared with non-users of each medication class (LD: 60.7 versus 45.5 pg/mL, p &lt; 0.0001; CCB: 49.5 versus. 44.4 pg/mL, p &lt; 0.0001). Adjusted regression models confirmed independent associations between TZ use and lower PTH (β = –3.2 pg/mL, p = 0.0007), and LD or CCB use and higher PTH (LD: β = +12.0 pg/mL, p &lt; 0.0001; CCB: +3.7 pg/mL, p &lt; 0.0001). Among CCB users, the use of dihydropyridines was independently associated with higher PTH (β = +5.0 pg/mL, p &lt; 0.0001), whereas non-dihydropyridine use was not (β = +0.58 pg/mL, p = 0.68). We conclude that in a large community-based cohort with normal kidney function, TZ use is associated with lower PTH, whereas LD and dihydropyridine CCB use is associated with higher PTH. These associations may provide a mechanistic explanation linking use of these medications to the development of skeletal outcomes. © 2016 American Society for Bone and Mineral Research.
Evidence for a Role for Nanoporosity and Pyridinoline Content in Human Mild Osteogenesis Imperfecta
Authors: Paschalis Eleftherios P , Gamsjaeger Sonja , Fratzl-Zelman Nadja , Roschger Paul , Masic Admir , Brozek Wolfgang , Hassler Norbert , Glorieux Francis H , Rauch Frank , Klaushofer Klaus , Fratzl Peter 
Published: January 2016

ABSTRACT

Osteogenesis imperfecta (OI) is a clinically and genetically heterogeneous connective tissue disorder characterized by bone fragility that arises from decreased bone mass and abnormalities in bone material quality. OI type I represents the milder form of the disease and according to the original Sillence classification is characterized by minimal skeletal deformities and near-normal stature. Raman microspectroscopy is a vibrational spectroscopic technique that allows the determination of bone material properties in bone biopsy blocks with a spatial resolution of ∼1 µm, as a function of tissue age. In the present study, we used Raman microspectroscopy to evaluate bone material quality in transiliac bone biopsies from children with a mild form of OI, either attributable to collagen haploinsufficiency OI type I (OI-Quant; n = 11) or aberrant collagen structure (OI-Qual; n = 5), as a function of tissue age, and compared it against the previously published values established in a cohort of biopsies from healthy children (n = 54, ages 1 to 23 years). The results indicated significant differences in bone material compositional characteristics between OI-Quant patients and healthy controls, whereas fewer were evident in the OI-Qual patients. Differences in both subgroups of OI compared with healthy children were evident for nanoporosity, mineral maturity/crystallinity as determined by maxima of the v1PO4 Raman band, and pyridinoline (albeit in different direction) content. These alterations in bone material compositional properties most likely contribute to the bone fragility characterizing this disease. © 2016 American Society for Bone and Mineral Research.
Integrative Analysis of Genomics and Transcriptome Data to Identify Potential Functional Genes of BMDs in Females
Authors: Chen Yuan-Cheng , Guo Yan-Fang , He Hao , Lin Xu , Wang Xia-Fang , Zhou Rou , Li Wen-Ting , Pan Dao-Yan , Shen Jie , Deng Hong-Wen 
Published: January 2016

ABSTRACT

Osteoporosis is known to be highly heritable. However, to date, the findings from more than 20 genome-wide association studies (GWASs) have explained less than 6% of genetic risks. Studies suggest that the missing heritability data may be because of joint effects among genes. To identify novel heritability for osteoporosis, we performed a system-level study on bone mineral density (BMD) by weighted gene coexpression network analysis (WGCNA), using the largest GWAS data set for BMD in the field, Genetic Factors for Osteoporosis Consortium (GEFOS-2), and a transcriptomic gene expression data set generated from transiliac bone biopsies in women. A weighted gene coexpression network was generated for 1574 genes with GWAS nominal evidence of association (p ≤ 0.05) based on dissimilarity measurement on the expression data. Twelve distinct gene modules were identified, and four modules showed nominally significant associations with BMD (p ≤ 0.05), but only one module, the yellow module, demonstrated a good correlation between module membership (MM) and gene significance (GS), suggesting that the yellow module serves an important biological role in bone regulation. Interestingly, through characterization of module content and topology, the yellow module was found to be significantly enriched with contractile fiber part (GO:044449), which is widely recognized as having a close relationship between muscle and bone. Furthermore, detailed submodule analyses of important candidate genes (HOMER1, SPTBN1) by all edges within the yellow module implied significant enrichment of functional connections between bone and cytoskeletal protein binding. Our study yielded novel information from system genetics analyses of GWAS data jointly with transcriptomic data. The findings highlighted a module and several genes in the model as playing important roles in the regulation of bone mass in females, which may yield novel insights into the genetic basis of osteoporosis. © 2016 American Society for Bone and Mineral Research.
Investigation on the Interaction of Hydroxyethyl Starch 130/0.4 (Voluven) and Serum Albumin for Pharmacokinetic and Toxicological Implications
Authors: Zhang Jianzhong , Huang Shaoyan , Han Yongbin , Wang Chenghai , Shao Wei , Fu Zhijian 
Published: January 2016

ABSTRACTThe interaction of hydroxyethyl starch 130/0.4 (Voluven) with human serum albumin (HSA) has been investigated by fluorescence (steady state and synchronous), Fourier transforms infrared (FT‐IR), and circular dichroism (CD) spectroscopies. Analysis of the fluorescence quenching data of HSA by Voluven using the Stern–Volmer method revealed the formation of 1:1 ground‐state complex. Evaluation of binding parameters and binding energy indicated that the binding reaction was exothermic. On the basis of fluorescence measurements, it was concluded that electrostatic forces play a crucial role in stabilizing the complex. The binding distance was calculated by using Förster resonance energy transfer (FRET) theory. The conformational changes of HSA were obtained qualitatively as well as quantitatively using synchronous fluorescence, FT‐IR, and CD. The HSA underwent partial unfolding in the presence of Voluven.
A Population Pharmacokinetic/Pharmacodynamic Model Predicts Favorable HDL Cholesterol Changes Over the First 5 Years in Children Treated With Current Efavirenz‐Based Regimens
Authors: Homkham Nontiya , Cressey Tim R. , Ingsrisawang Lily , Bouazza Naïm , Ngampiyaskul Chaiwat , Hongsiriwon Suchat , Srirojana Sakulrat , Kanjanavanit Suparat , Bhakeecheep Sorakij , Coeur Sophie Le , Salvadori Nicolas , Treluyer Jean Marc , Jourdain Gonzague , Urien Saik 
Published: January 2016

AbstractEfavirenz use is associated with changes in cholesterol concentrations, but it is unclear whether this effect is related to drug concentrations. Using efavirenz and cholesterol plasma concentrations measured in 87 antiretroviral‐naive children in Thailand, we assessed indirect response models to describe the evolution of high‐ and low‐density lipoprotein (HDL, LDL) cholesterol concentrations in relation to efavirenz plasma concentrations over time where efavirenz was assumed to either stimulate cholesterol production or inhibit its elimination. Simulations of cholesterol evolution for children with different average efavirenz concentrations (Cav) according to their assumed status of “fast” or “slow” metabolizers of efavirenz were performed. At treatment initiation, children's median (interquartile range, IQR) age was 8 years (5 to 10), body mass index z‐score 0.01 (–1.05 to 1.44), HDL 31 mg/dL (24 to 44), and LDL 83 mg/dL (69 to 100). Median (IQR) efavirenz Cav was 1.7 mg/L (1.3 to 2.1) during the period of observation. The best model describing the evolution of HDL and LDL cholesterol concentrations over time assumed that efavirenz inhibited their elimination. HDL concentrations increase over 5 years, whereas LDL concentrations increased only during the first 4 months and then returned to baseline levels afterward. Simulations predicted that, after 3 years, HDL would increase to 63 mg/dL in “fast” metabolizers and 97 mg/dL in “slow” metabolizers of efavirenz. The population pharmacokinetic‐pharmacodynamic (PK‐PD) model shows that favorable HDL cholesterol changes can be expected in children with current efavirenz dosing guidelines over 5 years of treatment.
Valorisation of heavy metals enriched tobacco biomass through slow pyrolysis and steam activation
Authors: Gonsalvesh Lenia , Yperman Jan , Carleer Robert , Mench Michel , Herzig Rolf , Vangronsveld Jaco 
Published: January 2016

AbstractBACKGROUNDThe disposal of metal‐enriched plant biomass is an important and still unresolved issue associated with phytoextraction. Therefore, the aim of this study was to valorise these contaminated biomasses into valuable products, i.e. bio‐chars and activated carbons (ACs), through slow pyrolysis followed by steam activation. The effects of pyrolysis/steam activation on metal availability in the chars/ACs were also evaluated. In addition, Cr(VI) adsorption by these ACs in aqueous solutions was studied.RESULTSRelevant chars/ACs yields were obtained due to applied thermochemical treatments. Leachability of heavy metals from those products was limited indicating that they may be safely applied as adsorption media. Prepared ACs demonstrated good Cr(VI) adsorption capacities occurring through a ‘coupled adsorption–reduction’ mechanism. It was found that Cr(VI) removal strongly depended on pH of Cr(VI) solutions and was higher for ACs activated at 800 °C. Among applied isotherm adsorption models, i.e. Langmuir and Freundlich, a better fit was obtained with the Langmuir model corresponding to monolayer coverage sorption of Cr(VI) on ACs surface.CONCLUSIONSHeavy metals enriched biomass can be successfully valorised through slow pyrolysis/steam activation into value added products, i.e. ACs that can be used as efficient and safe adsorbents for Cr(VI) removal. © 2016 Society of Chemical Industry
A multifunctional contrast dye for morphological research
Authors: Xia Qian , Feng Yuanbo , Yin Ting , Liu Yewei , Liang Sayuan , Liu Jianjun , Tong Linjun , Huang Gang , Yu Jie , Jiang Yansheng , Himmelreich Uwe , Oyen Raymond , Ni Yicheng 
Published: January 2016

ABSTRACTObjectivesWe sought to devise and test a multifunctional contrast dye agent for X‐ray based digital radiography (DR) or computer tomography (CT), magnetic resonance imaging (MRI), and colored staining in ex vivo validation part of animal experiments. Materials and Methods: The custom‐formulated contrast dye namely red iodized oil (RIO) was prepared by solubilizing a lipophilic dye Oil Red O in iodized poppy seed oil (Lipiodol or LPD) followed by physicochemical characterizations. To explore and test the utility of RIO, normal rats (n = 10) and rabbits (n = 10) with myocardial infarction (MI) were euthanized by overdose of pentobarbital for infusion of RIO through catheterization. The bodies and/or excised organs including heart, liver, spleen, kidneys, pancreas, and intestines of the rats and rabbits were imaged at clinical mammography, CT and MRI units. These images were qualitatively studied and quantitatively analyzed using Wilcoxon Rank test with a P value < 0.05 being considered of a statistically significant difference. Imaging findings were verified by histomorphology. Results: All experimental procedures were carried out successfully with the use of RIO. T1 and T2 relaxation time was 234.2 ± 2.6 ms and 141.9 ± 3.0 ms for RIO, close to that of native LPD. Proton (1H) NMR spectroscopy revealed almost identical profiles between RIO and native LPD. The clinical mammography unit, 128‐slice CT scanner and 3.0T MRI magnet were well adapted for the animal experiments. Combined use of RIO with DR, MRI, CT and histology enabled microangiography of the organs, 3D visualization of rat pancreas, validation of in vivo cardiac quantification of MI and cause determination of the rabbit death after coronary occlusion. RIO appeared as red droplets and vacuoles in vessels by frozen and paraffin sections. Image analysis showed the superiority of DR images, which provided better overall image quality (4.35 ± 0.49) for all analyzed liver vessel segments. MRI images revealed moderate to good overall image quality ratings (3.45 ± 0.52). Comparing the signal intensities of vessel and liver with different MRI sequences, all P values were <0.01. Conclusions: RIO proved to be a multifunctional contrast dye, which could be applied as an imaging biomarker for tissue vascularity or blood perfusion, for visualization of organ anatomy and for ex vivo validation of in vivo animal experiments. Microsc. Res. Tech. 79:111–121, 2016. © 2016 Wiley Periodicals, Inc.