bluuebunny/crossref_metadata_2025_split huggingface dataset:
Two‐color electrophoretic immunoassay for simultaneous measurement of insulin and glucagon content in islets of Langerhans
Authors: Guillo Christelle , Roper Michael G. 
Published: December 2007

AbstractA multianalyte CE competitive immunoassay using two‐color detection was developed to measure insulin and glucagon in islets of Langerhans. Insulin was quantified with FITC‐insulin (Ins*) and anti‐insulin antibodies (Ins Ab) and glucagon was quantified with Cy5‐glucagon (Glu*) and anti‐glucagon antibodies (Glu Ab). A 3 mW Ar+ laser at 488 nm and a 25 mW laser diode at 635 nm were used to excite FITC and Cy5, respectively. Fluorescence was split with a half‐silvered mirror and passed through a 520 ± 20 nm bandpass filter or a 663 nm longpass filter for the detection of insulin and glucagon, respectively. The two‐color detection format enabled independent quantitation of both analytes even with concentrations of insulin immunoassay reagents 20‐fold higher than glucagon reagents. Simultaneous calibration curves were generated and used to determine insulin and glucagon content in islets of Langerhans. Amounts of insulin and glucagon were 56.6 ± 3.2 and 1.0 ± 0.5 ng/islet, respectively. LODs were 7 nM insulin and 3 nM glucagon. The assay will be applicable to fast monitoring of multiple peptides secreted from islets of Langerhans and can be applied to other systems for the quantitation of multiple analytes with large differences in concentrations.
Determination of sulfophenyl carboxylic acids in agricultural groundwater samples by CE with ultraviolet absorption detection
Authors: Jiménez‐Díaz Inmaculada , Ballesteros Oscar , Vílchez José Luis , Navalón Alberto 
Published: December 2007

AbstractAn analytical method for the determination of six sulfophenyl carboxylic acids, namely (p‐sulfophenyl)acetic, 2‐(p‐sulfophenyl)propionic, 2‐(p‐sulfophenyl)butyric, 3‐(p‐sulfophenyl)butyric, 4‐(p‐sulfophenyl)butyric, and 5‐(p‐sulfophenyl)valerianic acid, in agricultural irrigation water samples was developed. It involves an SPE procedure, an on‐line preconcentration normal stacking mode and subsequent separation and determination using CE with UV detection (CE‐UV). p‐Sulfobenzoic acid was used as internal standard. The compounds were separated with an uncoated capillary and a 25 mM ammonium acetate/acetic acid buffer solution (pH 5.5) with 2‐propanol (30% v/v) and 0.75 mM CTAB. Analyses were run at −25 kV, 25°C, and 100 s of hydrodynamic injection with UV detection at 225 nm. Quantification limits found ranged between 4 and 6 ng/mL. The proposed method was validated using a recovery assay. It was satisfactorily used for the determination of these compounds in groundwater samples to track down the biodegradation of linear alkylbenzene sulfonates in an agricultural soil from the fertile plain of Granada (Spain).
CE combined with rolling circle amplification for sensitive DNA detection
Authors: Li Ni , Li Jishan , Zhong Wenwan 
Published: December 2007

AbstractHere we describe an assay which combines CE with rolling circle amplification (RCA) for sensitive DNA detection and quantification. RCA is an isothermal DNA replication technique that generates a long ssDNA with tandem repeats. It requires simpler temperature control in reaction and offers higher sequence specificity and greater quantitation capability compared to other amplification technologies. In this study, RCA amplified the DNA target via a circular template, and the product was digested into monomers for CE analysis. Less than 2 fmol of the DNA target could easily be detected using this RCA‐CE assay and the assay has a dynamic range of two orders of magnitudes. Moreover, simultaneous detection of both the target DNA and the internal standard was achieved by designing two padlock probes with different sizes, which could significantly improve the quantification accuracy. The RCA‐CE assay is easy to perform, readily adaptable for detection of multiple targets because of the high resolution power of CE, and is compatible with other applications employing RCA as a signal amplification tool. Additionally, this assay can be used with a capillary array system to perform sensitive, high‐throughput genetic screening.
Nanofibrous matrices of poly(lactic acid) and gelatin polymeric blends for the improvement of cellular responses
Authors: Kim Hae‐Won , Yu Hye‐Sun , Lee Hae‐Hyoung 
Published: December 2007

AbstractSubstrates with a nanofibrous morphology are considered as a prospective matrix to populate and support cells in the tissue regeneration area. Although the nanofibers made of synthetic degradable polymers, including poly(lactic acid) (PLA), have been well studied, their poor cell affinity has restricted wider applications. Herein, we produced blending nanofibers made of PLA and gelatin to improve the cellular responses of PLA. For this, both PLA and gelatin were dissolved in an organic solvent, varying the compositions of PLA:gelatin at 1:3 and 1:1 by weight, and the solutions were electrospun into nanofibers. At all compositions, nanofibers could be successfully generated with diameters of approximately hundreds of nanometers. The addition of gelatin into PLA markedly improved the wettability of the nanofibrous substrate. The osteoblastic cells attached and spread well on all the blending nanofibers and pure PLA. In particular, the cellular growth was significantly higher on the gelatin‐blended PLA than on the pure PLA nanofiber. On the basis of this study, the PLA/gelatin blending polymeric nanofibers are considered to be useful as a bone cell supporting matrix in the tissue regeneration area. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Porous β‐tricalcium phosphate/collagen composites prepared in an alkaline condition
Authors: Zou Chao , Weng Wenjian , Cheng Kui , Du Piyi , Shen Ge , Han Gaorong , Guan Binggang , Yan Weiqi 
Published: December 2007

AbstractBone substitute materials with natural bone‐like structure are considered to be favorable for bone regeneration. In this work, porous β‐tricalcium phosphate (β‐TCP)/collagen composite consisting of bone‐like microstructural units was prepared using nanosized β‐TCP particles and alkaline‐disassembled collagen. The resulting composite showed a good interconnecting porous structure with ∼90% porosity and 100 ∼ 300 μm pore size. The pore walls were dense, and the combination status of collagen and nanosized β‐TCP particles demonstrated that nanosized β‐TCP particles tightly connected collagen microfibrils as a bone‐like microstructural unit. MTT and alkaline phosphatase (ALP) assays showed that the porous composite had enhanced effects on cellular proliferation and activity of osteoblast compared with a control of pure collagen. It is suggested that the adoption of nanosized β‐TCP particles is a main contribution to the formation of the composite with a bone‐like microstructural unit, and the unique microstructure could be a main role for the composite to have the positive influence on osteoblast cell proliferation. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Mechanism of calcium disilicide‐induced calcification of crystalline silicon surfaces in simulated body fluid under zero bias
Authors: Seregin Vladimir V. , Coffer Jeffery L. 
Published: December 2007

AbstractA dry‐etch spark ablation method was used to produce calcium disilicide (CaSi2/Si) layers on silicon surfaces, and their biomineralization under zero bias was followed by means of scanning electron microscopy, X‐ray energy dispersive analysis, and Raman spectroscopy. CaSi2/Si wafers are bioinert at 25°C and bioactive at 37°C. Mechanistic insights regarding biomineralization were derived from an analysis of film growth morphology and chemical composition after various soaking periods in standard simulated body fluid (SBF). Changes in CaSi2 calcification behavior as a function of reaction temperature and pH, SBF concentration, and various surface modification processes were also employed for this purpose. During CaSi2/Si calcification under zero bias, calcium phosphate (CaP) growth is strongly dependent on the structural degradation of CaSi2 grains. Surface silanol groups, initially present on the as‐prepared material, cannot induce CaP nucleation, which begins only upon delamination of CaSi2 layers. The calcium phosphate phases, which are present during various growth stages, possibly include a combination of Mg‐substituted whitlockite, monetite, and tricalcium phosphate. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Biodegradable and thermoreversible hydrogels of poly(ethylene glycol)‐poly(ε‐caprolactone‐co‐glycolide)‐poly(ethylene glycol) aqueous solutions
Authors: Jiang Zhiqiang , Hao Jianyuan , You YuJing , Liu Yan , Wang Zhenhong , Deng Xianmo 
Published: December 2007

AbstractThe aqueous solutions of triblock copolymers of poly(ethylene glycol)–poly(ϵ‐caprolactone‐co‐glycolide)–poly(ethylene glycol) [PEG–P(CL‐GA)–PEG] undergoing sol–gel transition as the temperature increases from 20 to 60°C were successfully prepared. The thermogelling block copolymers were synthesized by subtle control of the hydrophilic/hydrophobic balance and the chain microstructures. The amphiphilic block copolymer formed micelles in aqueous solution, and the micelle aggregated as the temperature increased. The sol–gel transition of the copolymer aqueous solutions was studied focusing on the structure–property relationship. GA was incorporated into the polymer chain to prevent crystallization of PCL component and increase the polymer degradation. It is expected to be a promising long‐term delivery system for pH‐sensitive drugs, proteins, and genes. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Adhesion of protein residues to substituted (111) diamond surfaces: An insight from density functional theory and classical molecular dynamics simulations
Authors: Borisenko Konstantin B. , Reavy Helen J. , Zhao Qi , Abel Eric W. 
Published: December 2007

AbstractProtein‐repellent diamond coatings have great potential value for surface coatings on implants and surgical instruments. The design of these coatings relies on a fundamental understanding of the intermolecular interactions involved in the adhesion of proteins to surfaces. To get insight into these interactions, adhesion energies of glycine to pure and Si and N‐doped (111) diamond surfaces represented as clusters were calculated in the gas phase, using density functional theory (DFT) at the B3LYP/6‐31G* level. The computed adhesion energies indicated that adhesion of glycine to diamond surface may be modified by introducing additional elements into the surface. The adhesion was also found to induce considerable change in the conformation of glycine when compared with the lowest‐energy conformer of the free molecule. In the Si and N‐substituted diamond clusters, notable changes in the structures involving the substituents atoms when compared with smaller parent molecules, such as 1‐methyl‐1‐silaadamantane and 1‐azaadamantane, were detected. Adhesion free energy differences were estimated for a series of representative peptides (hydrophobic Phe‐Gly‐Phe, amphiphilic Arg‐Gly‐Phe, and hydrophilic Arg‐Gly‐Arg) to a (111) diamond surface substituted with different amounts of N, Si, or F, using molecular dynamics simulations in an explicit water environment employing a Dreiding force field. The calculations were in agreement with the DFT results in that adsorption of the studied peptides to diamond surface is influenced by introducing additional elements to the surface. It has been shown that, in general, substitution will enhance electrostatic interactions between a surface and surrounding water, leading to a weaker adhesion of the studied peptides. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res 86A: 1113–1121, 2008
Mechanical and chemical characteristics of an autologous glue
Authors: De Somer Filip , Delanghe Joris , Somers Pamela , Debrouwere Maarten , Van Nooten Guido 
Published: December 2007

AbstractThe study evaluates the mechanical and chemical characteristics of autologous surgical glue made by mixing ultrafiltered plasma with glutaraldehyde (GTA). Human albumin 200 g/L mixed with different concentrations of GTA (25, 50, 75, or 100 g/L) was used as a single protein set‐up for testing tensile strength, elasticity, and rate of crosslinking. Subsequently, ultrafiltered canine or human plasma to obtain autologous glue replaced human albumin. BioGlue, a surgical glue, and Tissucol Duo, a fibrin sealant, were used as controls. Tensile strength of human albumin 200 g/L mixed with 75 g/L GTA is 825 ± 109 N versus 672 ± 167 N for BioGlue. Ultrafiltered canine plasma showed a maximum tensile strength of 634 ± 137 N when mixed with GTA 75 g/L. For human plasma, the maximum tensile strength of 436 ± 69 N was reached after mixing with GTA 25 g/L. Autologous glue had a higher elasticity of 144 ± 66 N versus 322 ± 104 N for BioGlue at maximum load. Autologous glues for vascular repair can be easily prepared out of the patient's plasma. The optimal characteristics, compared to BioGlue, are obtained for ultrafiltered canine and human plasma by mixing with a GTA concentration of 50–75 g/L and 25–50 g/L, respectively. The autologous glue will exert less tensile strength than BioGlue but has a better compliance. In case where no plasma can obtained from the patient, mixing human albumin 200 g/L with GTA 75 g/L can be an alternative to BioGlue. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Paclitaxel release from single and double‐layered poly(DL‐lactide‐co‐glycolide)/poly(L‐lactide) film for biodegradable coronary stent application
Authors: Lao Luciana Lisa , Venkatraman Subbu S. 
Published: December 2007

AbstractOur laboratory has been developing a completely biodegradable coronary stent which is made of bilayers of biodegradable polyesters. This article presents the preliminary work done to exploit the drug delivery potential of such a polymeric stent. An antiproliferative drug (paclitaxel) was added either only to the top layer or to both layers and the in vitro release profiles were monitored for up to 90 days. Within 90 days, the measured paclitaxel release was almost entirely from the P(DL)LGA layer. In general, the release profiles show three distinct stages: (a) extremely slow diffusional release, (b) accelerated diffusion‐degradation release, and (c) saturation. Separate degradation studies (water absorption, molecular weight reduction, weight loss, and surface topography) were also conducted to better understand the observed release behavior. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Therapeutic plasma exchange performed in parallel with extra corporeal membrane oxygenation for antibody mediated rejection after heart transplantation
Authors: Jhang Jeffrey , Middlesworth William , Shaw Rose , Charette Kevin , Papa Joey , Jefferson Rashida , Torloni Antonio S. , Schwartz Joseph 
Published: December 2007

AbstractWe report on the feasibility, safety, and efficacy of performing therapeutic plasmapheresis (TPE) in parallel with extracorporeal membrane oxygenation (ECMO) to alleviate antibody mediated rejection (AMR) after heart transplantation. Two pediatric and one adult patient presented with severe congestive heart failure and respiratory distress after heart transplantation and required ECMO support. TPE was initiated to treat AMR while patients remained on ECMO. Each patient received three to five procedures either every day or every other day. One equivalent total plasma volume (TPV) was processed for each procedure (patient TPV + ECMO extracorporeal TPV). A total of 13 TPE procedures were performed with 12 procedures completed without complications or adverse events; one procedure was terminated before completion because of cardiac arrhythmia. Anti‐HLA antibody titers decreased after TPE in all three patients. Ventricular function improved and ECMO was discontinued in 2 of 3 patients. Performing large volume TPE with a processed volume up to 2.5 times the patient's TPV is well tolerated in both pediatric (≤ 10 kg) and adult patients. TPE in parallel with ECMO is feasible, safe, and may be measurably effective at reducing anti‐HLA antibodies and should be considered as part of the treatment for patients with early AMR after heart transplantation. J. Clin. Apheresis, 2007. © 2007 Wiley‐Liss, Inc.
Performance of a new separator system for routine autologous hematopoietic progenitor cell collection in small children
Authors: Witt Volker , Beiglböck Elisabeth , Ritter Robert , Würth Marianne , Peters Christine , Ladenstein Ruth , Gadner Helmut , Fritsch Gerhard 
Published: December 2007

AbstractThe AMICUS™ system was recently introduced for peripheral blood stem cell (PBSC) aphereses in adults. We conducted a single center field evaluation to obtain data about the performance of this system in children with a body weight (bw) < 25 kg. Results of blood priming procedures were compared to historical data obtained with the Fenwal CS3000+ (CS 3000). From August, 2001 to February, 2007, 47/178 (26%) PBSC aphereses procedures were performed in our institution with the AMICUS™ system in 35 small patients (median bw 13.9 kg; range 6.7–24; age 2.78 years; range 0.97–7.06). The patients suffered from various malignant primary diseases or recurrences. We primed the system with packed RBC in case of >30% dilution of the RBC volume (n = 31) or with saline (n = 16). Compared to the CS3000, the AMICUS™ revealed comparable collection efficiencies (CE) for CD34+ cells (median 67%, range 26–120), lymphocytes (75%, 25–138), monocytes (54%, 23–173), and granulocytes (10%, 1.5–36), MNC (57% 24–125), but a significantly higher erythrocyte and granulocyte, and a lower platelet CE. There was a significant negative correlation between total leukocyte count and CE for MNC (r = −0.566; P < 0.001) and CD34+ cells (r = −0.517; P < 0.001). There was no significant statistical or clinical difference between the CE in blood‐primed procedures and saline‐primed procedures. With the AMICUS™ we saw statistically less citrate reactions compared to the CS 3000. We conclude that the AMICUS™ system is safe and efficient to harvest PBSC on a routine basis in pediatric patients, even in children ≤10 kg bw. J. Clin. Apheresis, 2007. © 2007 Wiley‐Liss, Inc.
Tyrosine phosphorylation controls nuclear localization and transcriptional activity of Ssdp1 in mammalian cells
Authors: Dey‐Guha Ipsita , Malik Nasir , Lesourne Renaud , Love Paul E. , Westphal Heiner 
Published: December 2007

AbstractThe LIM‐HD proteins interact with different cofactors, including Ssdp1 to regulate development in a diverse range of species. The single stranded DNA binding protein (Ssdp1) is a member of an evolutionarily conserved family of proteins that regulate critical transcriptional processes during embryonic development. Ssdp1 is localized predominantly in the cytoplasm of 293T cells but is translocated to the nucleus when co‐transfected with Lck, a member of the Src family of non‐receptor tyrosine kinases. The Src tyrosine kinase inhibitor PP2 blocked the nuclear translocation of Ssdp1. Western blot analysis showed that co‐expression of Ssdp1 and Lck in 293T cells induces Ssdp1 phosphorylation. Mutation of the Ssdp1 N terminal tyrosine residues 23 and 25 markedly reduced both the phosphorylation and the nuclear localization of Ssdp1. Lck enhanced the transcriptional activity of Ssdp1 in the context of known components of a LIM‐homeodomain (LIM‐HD)/cofactor complex. We propose that phosphorylation involving N‐terminal tyrosine residues of Ssdp1 is a means of regulating its nuclear localization and subsequent transcriptional activation of LIM‐HD complexes. J. Cell. Biochem. 103: 1856–1865, 2007. © 2007 Wiley‐Liss, Inc.
Disease‐modifying effects of Glucosamine HCl involving regulation of metalloproteinases and chemokines activated by interleukin‐1β in human primary synovial fibroblasts
Authors: Lu Hsien‐Tsung , Liang Yu‐Chih , Sheu Ming‐Thau , Ho Hsiu‐O , Lin Ya‐Ting , Hsieh Ming‐Shium , Chen Chien‐Ho 
Published: December 2007

AbstractThe purpose of this study was to investigate the possible involvement of synovium in cartilage destruction in osteoarthritis (OA) patients. Using human primary synovial fibroblasts (HPSFs), we examined the effects of glucosamine (GLN) on the regulation of the expression of matrix metalloproteinases (MMP‐1, ‐2, and ‐13) and chemokines (IL‐8, MCP‐1, and RANTES) as well as the involvement of MAPK signal pathways (JNK, ERK, and p‐38) and the transcription factor of NF‐κB on the present or absence of interleukin (IL)‐1β. Our experiments showed that protein production and mRNA expressions of MMP‐1, MMP‐3, MMP‐13, IL‐8, MCP‐1, and RANTES were downregulated by treatment with glucosamine in HPSFs. The results further showed that GLN could inhibit IκBα phosphorylation and IκBα degradation leading to inhibition of the translocation of NF‐κB to nuclei. However, GLN upregulated MAPKs pathways in HPSFs cells with or without IL‐1β. The results suggest that the inhibition of MMP‐1, ‐3, and ‐13 expressions as well as IL‐8, MCP‐1, and RANTES productions by GLN might mediate suppression of NF‐κB signal pathways, and HPSFs seem to have a potential functions as an alternative source of MMPs and chemokines for inducing the degradation of cartilage in OA. J. Cell. Biochem. 104: 38–50, 2008. © 2007 Wiley‐Liss, Inc.
On the application of ‘seeding’ techniques in the primary separation of plasmid DNA from neutralised E. coli lysates
Authors: Theodosiou Eirini , Thomas Owen RT 
Published: December 2007

AbstractBACKGROUND: Initial extraction of plasmid DNA from Escherichia coli and its separation from host‐derived contaminants is a difficult task to perform. Here, we examine the application of particle ‘seeding’ solid–liquid separation methods for primary recovery of plasmid DNA from neutralised alkaline cell lysates.RESULTS: Planting magnetic particle ‘seeds’ during cell lysis resulted in enhanced phase separation, facile magnetic separation of the floc, slight improvements in plasmid purity, but diminished plasmid recoveries. When CaCO3‐coated low‐density microspheres were seeded into flocs, phase separation was impaired, shear‐induced floc damage and contamination of the plasmid liquor with genomic DNA and cell debris occurred, but plasmid DNA recovery was improved. Introduction of hydrophobic low‐density microspheres into the floc dramatically improved floc stiffness, phase separation and flotation efficiency, and reduced the solids content in the plasmid liquor 10‐fold. However, strong reinforcement of the cell debris lattice by these microspheres hindered plasmid release into the liquor beneath.CONCLUSION: By incorporating magnetic or buoyant seeds during cell lysis we have identified new routes for separation of shear‐sensitive cell debris solids from crude plasmid‐containing liquors. Effective use of seeding approaches for difficult solid–liquid separation tasks will require evaluation of a wide range of seeds of varying architecture, size, shape, density and chemistry. Copyright © 2007 Society of Chemical Industry