bluuebunny/crossref_metadata_2025_split huggingface dataset:
Anin vitrostudy of collagen hydrogel to induce the chondrogenic differentiation of mesenchymal stem cells
Authors: Zhang Li , Yuan Tun , Guo Likun , Zhang Xingdong 
Published: May 2012

AbstractIt is controversial whether a biomaterial itself, rather than addition of any exogenous growth factor, could induce mesenchymal stem cells (MSCs) to differentiate into chondrogenic lineage, further to regenerate cartilage. Previous studies have shown that collagen‐based hydrogel could induce MSCs to differentiate into chondrocytesin vivobut thein vitrostudies only have a few reports. The evidence that biomaterials could induce chondrogenesis is not adequate. In this study, we tried to address whether type I collagen hydrogel has chondro‐inductive capabilityin vitroand how this scaffold induces MSCs to generate cartilage tissue without exogenous growth factors in the culture medium. We encapsulated neonatal rabbit bone marrow mesenchymal stem cells (BMSCs) in type I collagen hydrogel homogeneously or implanted cell aggregates in hydrogel, and cultured them in nonchondrogenic inductive media. After at least 28 days culture, cells in the homogeneous group were tending to chondrogenic differentiation while cell density was high, and cells in the aggregate group have almost gone through chondrogenesis and formed neo‐cartilage tissue with abundant specific extracellular matrix (ECM) deposition. These results indicate collagen hydrogel has inherent inductivity for the chondrogenic differentiation of BMSCs, and the optimum specification and tissue formation were accompanied with local high cell density. This research suggests a feasible strategy to induce the chondro differentiation of BMSCs independent of exogenous growth factors, which may greatly contribute to clinical cartilage regeneration. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A 100A: 2717–2725, 2012.
Activated charcoal composite biomaterial promotes human embryonic stem cell differentiation toward neuronal lineage
Authors: Chen Eric Y. T. , Wang Yung‐Chen , Mintz Alexander , Richards Alan , Chen Chi‐Shuo , Lu David , Nguyen Thien , Chin Wei‐Chun 
Published: May 2012

AbstractTransplantation of biomaterial scaffolds encasing human embryonic stem cells (hESCs) has been proposed as a clinical therapy for various neurological lesions and disorders. In light of recent developments, artificially synthesized carbon‐based biomaterials such as carbon nanotubes and graphene have demonstrated feasibility in supporting stem cell attachment and differentiation. However, the applicability is significantly hampered by evidence of nanotoxic effects on multiple cell types. Thus, an emergent drive for an innovative carbonaceous biomaterial calls for a safer platform with comparable advantageous characteristics. Here, we showed for the first time, a natural coal‐based activated charcoal (AC) composite biosubstrate can support and promote neuronal differentiation in hESCs. The bio‐friendly AC composite biomatrices resulted in more matured neuron‐like cells. Both of axonal length and density were at least twice as long and abundant, respectively, when compared with control groups. A functional assay demonstrated that the derived neuron‐like cells responded to depolarization‐dependent synaptic recycling and may contain active synapses. In addition, the AC composite substrate can serve to concentrate growth factors and cell adhesion proteins, further encouraging attachment and hESC differentiation. Moreover, the AC composite biomaterial can potentially be economically manufactured as implantable three‐dimensional bioscaffolds, facilitating the regeneration of damaged neural and other tissues. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2012.
Development of a broad spectrum polymer‐released antimicrobial coating for the prevention of resistant strain bacterial infections
Authors: Sinclair K. D. , Pham T. X. , Farnsworth R. W. , Williams D. L. , Loc‐Carrillo C. , Horne L. A. , Ingebretsen S. H. , Bloebaum R. D. 
Published: May 2012

AbstractMore than 400,000 primary hip and knee replacement surgeries are performed each year in the United States. From these procedures, approximately 0.5–3% will become infected and when considering revision surgeries, this rate has been found to increase significantly. Antibiotic‐resistant bacterial infections are a growing problem in patient care. This in vitro research investigated the antimicrobial potential of the polymer released, broad spectrum, Cationic Steroidal Antimicrobial‐13 (CSA‐13) for challenges against 5 × 108 colony forming units (CFU) of methicillin‐resistant Staphylococcus aureus (MRSA). It was hypothesized that a weight‐to‐weight (w/w) concentration of 18% CSA‐13 in silicone would exhibit potent bactericidal potential when used as a controlled release device coating. When incorporated into a polymeric device coating, the 18% (w/w) broad‐spectrum polymer released CSA‐13 antimicrobial eliminated 5 × 108 CFU of MRSA within 8 h. In the future, these results will be utilized to develop a sheep model to assess CSA‐13 for the prevention of perioperative device‐related infections in vivo. Published 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 100A: 2732–2738, 2012.
DLC coatings for UHMWPE: Relationship between bacterial adherence and surface properties
Authors: Del Prado G. , Terriza A. , Ortiz‐Pérez A. , Molina‐Manso D. , Mahillo I. , Yubero F. , Puértolas J. A. , Manrubia‐Cobo M. , Gómez Barrena E. , Esteban J. 
Published: May 2012

AbstractDevelopment of intrinsically antibacterial surfaces is of key importance in the context of prostheses used in orthopedic surgery. This work presents a thorough study of several plasma‐based coatings that may be used with this functionality: diamond‐like carbon (DLC), fluorine‐doped DLC (F‐DLC), and a high‐fluorine‐content‐carbon‐fluor polymer (CFX). The coatings were obtained by a radio‐frequency plasma‐assisted deposition on ultra high molecular weight polyethylene (UHMWPE) samples and physicochemical properties of the coated surfaces were correlated with their antibacterial performance against collection and clinical Staphylococcus aureus and Staphylococcus epidermidis strains. The fluorine content and the relative amount of CC and CF bonds were controlled by X‐ray photoelectron spectroscopy, and hydrophobicity and surface tension by contact angle measurements. Surface roughness was studied by Atomic Force Microscopy. Additional nanoidentation studies were performed for DLC and F‐DLC coatings. Unpaired t test and regression linear models evaluated the adherence of S. aureus and S. epidermidis on raw and coated UHMWPE samples. Comparing with UHMWPE, DLC/UHMWPE was the least adherent surface with independence of the bacterial species, finding significant reductions (p ≤ 0.001) for nine staphylococci strains. Bacterial adherence was also significantly reduced in F‐DLC/ UHMWPE and CFx/UHMWPE for six strains. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A 100A:2813–2820, 2012.
Gene expression during S. epidermidis biofilm formation on biomaterials
Authors: Patel Jasmine D. , Colton Erica , Ebert Michael , Anderson James M. 
Published: May 2012

AbstractBiomaterial‐centered infections are initiated by adhesion of bacteria to an implant, followed by colonization and mature biofilm formation. Staphylococcus epidermidis is commonly identified as the cause of these device‐centered infections. This study used an in vitro model to evaluate temporal changes in the expression of genes—icaADBC, agrBDCA, aap, and atle—that have been identified to play a role in the pathogenesis of S. epidermidis infections. Real‐time reverse transcription–polymerase chain reaction was used to determine changes in gene expression from S epidermidis biofilm grown on polyurethanes (Elasthane 80A, hydrophobic) modified with polyethylene oxide (Elasthane 80A–6PEO, hydrophilic) and fluorocarbon (Elasthane 80A–6F, hydrophobic). In vitro expression of the ica locus, which is involved in initial adhesion and intracellular aggregation, increased up to 100‐fold from 2 to 48 h, whereas gene expression for autolysin AtlE decreased slightly from 2 to 12 h, followed by a 10‐fold increase by 48 h. Upregulation of the aap gene associated with bacterial accumulation and the agr quorum‐sensing system was observed during biofilm formation over 48 h. In addition, no correlation was observed between S. epidermidis gene expression and biomaterial surface chemistry. This study used an in vitro model to demonstrate that enhanced expression of the atle, aap, agr, and ica genes plays an important role in initial foreign body colonization and potentially in the establishment of a device‐associated infection. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 100A:2863–2869, 2012.
Serum Creatinine Determined by Jaffe, Enzymatic Method, and Isotope Dilution‐Liquid Chromatography‐Mass Spectrometry in Patients Under Hemodialysis
Authors: Liu Wen‐Sheng , Chung Yu‐Ting , Yang Chih‐Yu , Lin Chih‐Ching , Tsai Kun‐Hung , Yang Wu‐Chang , Chen Tzen‐Wen , Lai Yen‐Ting , Li Szu‐Yuan , Liu Tsung‐Yun 
Published: May 2012

ObjectivesSerum creatinine is an important clinical marker for renal clearance. However, the Jaffe method had much interference and the accuracy had not been tested in patients under hemodialysis (HD) with standard isotope dilution‐liquid chromatography‐mass spectrometry (IDLCMS) method. The validity of enzymatic method is also unknown.MethodsThe predialysis serum creatinine levels of 126 patients under regular HD for 3 months were checked by Jaffe, enzymatic, and IDLCMS methods. We compared the value of the Jaffe and enzymatic to that of IDLCMS in linear regression model. And we also tried to find the clinical parameters that influence the difference between Jaffe vs. IDLCMS and enzymatic vs. IDLCMS method.ResultsWe found significant underestimate serum creatinine in uremic patients by Jaffe and enzymatic methods. Serum glucose and globulin are positive biases, whereas albumin, potassium, and phosphorus are negative biases. Enzymatic method is less affected by serum glucose and serum protein. Albumin acts differently in uremic serum compared to the results of mixing them with normal serum.ConclusionsFor uremic patients, in whom creatinine level is high and many of them suffered from diabetes mellitus, serum creatinine can be either under‐ or overestimated by Jaffe method. Enzymatic method is less affected and may be a better method. J. Clin. Lab. Anal. 26:206‐214, 2012. © 2012 Wiley Periodicals, Inc.
The Use of Oral Fluid Samples Spotted on Filter Paper for the Detection of Measles Virus Using Nested RT‐PCR
Authors: Sheikhakbari Sogol , Mokhtari‐Azad Talat , Salimi Vahid , Norouzbabaei Zahra , Abbasi Simin , Zahraei Seyed Mohsen , Shahmahmoodi Shohreh 
Published: May 2012

Measles is the leading cause of death in infants, although a vaccine is available for its prevention. At this stage of measles elimination and eradication, it is so important to confirm clinically diagnosed measles cases in the laboratory but, developing countries have troubles in collecting and maintaining the cold chain of the specimens while transporting them to the laboratories. Therefore, filter papers are good candidates for simplification of specimen collection and transportation. In this research, the effects of the temperature, at which the dried specimens were kept, and the time duration the dried specimens were kept before being tested, were studied.Since there were not enough patients’ oral fluid samples available, a nested reverse transcriptase PCR (RT‐PCR) that detected measles virus (MV) from dried filter papers was set up using MV infected cells diluted in sterile phosphate‐buffered saline (PBS). Dried specimens were stored at −25°C, 4°C, and room temperature for 1 day, 1, 2, and 3 weeks before being tested. This method was then applied to filter paper oral fluids collected from nine clinically diagnosed measles patients in Iran in 2010 which were tested after being kept at room temperature for 1 day, 1 and 3 weeks after preparation.The results showed that dried oral fluids on filter papers are reliable specimens for the detection of MV RNA using nested RT‐PCR, but the nested RT‐PCR results of low titer viruses dried onto filter papers are not reproducible and reliable. J. Clin. Lab. Anal. 26:215‐222, 2012. © 2012 Wiley Periodicals, Inc.
It Means Everything: Continuing Normality of Everyday Life for People with Rheumatoid Arthritis in Early Remission
Authors: Kristiansen T. M. , Primdahl J. , Antoft R. , Hørslev‐Petersen K. 
Published: May 2012

AbstractObjectiveThe aim of this follow‐up study was twofold: firstly, to explore how people who were clinically regarded to be in a state of remission experienced their everyday lives with rheumatoid arthritis (RA); secondly, to explore the experiences of people in early remission with healthcare provision and their perceived support needs.MethodsTwo focus group interviews were conducted with 11 participants in total. Interview data were analysed using content analysis methods.ResultsAll participants felt that they were able to continue their normal everyday activities at home, at leisure and at work. They were also able to maintain their normal roles. Continuing the normality of everyday life seemed to be the most important defining variable for experiencing being in remission. Support needs were directly related to the participants' positive experiences of actual support from the healthcare providers and were related to the continuity of the care provider, coherence, being taken care of, having a personal and trusting relationship with the health professionals and being properly informed about RA and how to manage it.ConclusionThe participants wanted to concentrate on wellness and tended to avoid thinking of possible side effects, being chronic ill and the development of RA in the future. Copyright © 2012 John Wiley & Sons, Ltd.
A bi‐value coding parameterization scheme for the discrete optimal orientation design of the composite laminate
Authors: Gao Tong , Zhang Weihong , Duysinx Pierre 
Published: May 2012

SUMMARYThe discrete optimal orientation design of the composite laminate can be treated as a material selection problem dealt with by using the concept of continuous topology optimization method. In this work, a new bi‐value coding parameterization (BCP) scheme of closed form is proposed to this aim. The basic idea of the BCP scheme is to ‘code’ each material phase using integer values of +1 and –1 so that each available material phase has one unique ‘code’ consisting of +1 and/or –1 assigned to design variables. Theoretical and numerical comparisons between the proposed BCP scheme and existing schemes show that the BCP has the advantage of an evident reduction of the number of design variables in logarithmic form. The benefit is particularly remarkable when the number of candidate materials becomes important in large‐scale problems. Numerical tests with up to 36 candidate material orientations are illustrated for the first time to indicate the reliability and efficiency of the BCP scheme in solving this kind of problem. It proves that the BCP is an interesting and valuable scheme to achieve the optimal orientations for large‐scale design problems. Besides, a four‐layer laminate example is tested to demonstrate that the proposed BCP scheme can easily be extended to multilayer problems. Copyright © 2012 John Wiley & Sons, Ltd.
Differential effects of radiotherapy on growth and endocrine function among acute leukemia survivors: A childhood cancer survivor study report
Authors: Chow Eric J. , Liu Wei , Srivastava Kumar , Leisenring Wendy M. , Hayashi Robert J. , Sklar Charles A. , Stovall Marilyn , Robison Leslie L. , Baker K. Scott 
Published: May 2012

AbstractBackgroundThe differential effects of cranial radiotherapy (CRT), spinal radiotherapy (SRT), and total body irradiation (TBI) on growth and endocrine outcomes have rarely been examined in combination among childhood acute leukemia survivors.ProcedureSelf‐reported height/weight, hypothyroidism, and pregnancy/live birth were determined among acute lymphoblastic and myeloid leukemia survivors (n = 3,467) participating in the Childhood Cancer Survivor Study, an ongoing cohort study of 5‐year survivors of pediatric cancers diagnosed from 1970 to 1986.ResultsCompared with no radiotherapy, risk estimates were consistent across outcomes (adult short stature, hypothyroidism, absence of pregnancy/live birth) with CRT treatment associated with 2–3‐fold increased risks, TBI associated with 5–10 fold increased risks, and CRT + TBI associated with >10 fold increased risks. Exposure to any SRT further increased risk of these outcomes 2–3‐fold. Changes in body composition were more nuanced as CRT only was associated with an increased risk of being overweight/obese (OR 1.6, 95% CI 1.3–1.9) whereas TBI only was associated with an increased risk of being underweight (OR 6.0, 95% CI 2.4–14.9).ConclusionsAlthough patients treated with CRT + TBI were at greatest risk for short stature, hypothyroidism, and a reduced likelihood of pregnancy/live birth, those treated with either modality alone had significantly increased risks as well, including altered body composition. Any SRT exposure further increased risk in an independent fashion. Pediatr Blood Cancer 2013; 60: 110–115. © 2012 Wiley Periodicals, Inc.
Electrical conductivity and oxygen permeability of polyacrylonitrile/multiwalled carbon nanotubes composites
Authors: Pradhan Ajaya K. , Swain Sarat K. 
Published: May 2012

AbstractPolyacrylonitrile (PAN)/Multiwalled carbon nanotube (MWCNT) nanocomposites were prepared by nonconventional ultrasonic‐assisted emulsifier free emulsion polymerization technique with variable percentage of functionalized carbon nanotube. PAN/MWCNT nanocomposites were characterized by ultraviolet‐visible (UV‐visible) spectroscopy and Fourier transform infrared (FTIR) spectroscopy. The result from UV‐visible suggested that the functionalized MWCNT had interfacial interaction with PAN matrices. The surface morphology of functionalized MWCNT and PAN/MWCNT nanocomposites were studied by scanning electron microscopy (SEM). Electrical properties of PAN/MWCNT nanocomposites were measured and the result indicated that the conductivity increased with increasing concentration of MWCNTs. The oxygen permeability of PAN/MWCNT nanocomposites gradually increased with increase of MWCNT concentration, the result which was in agreement with the vertical alignment ofMWCNT in SEM. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers
Effects of alkalization on tensile, impact, and fatigue properties of hemp fiber composites
Authors: Shahzad Asim 
Published: May 2012

AbstractThe effects of alkalization surface treatment on hemp fiber properties and the properties of hemp fiber–reinforced polyester composites have been studied. Hemp fibers were exposed to 1, 5, and 10% sodium hydroxide (NaOH) solutions. The tensile properties and interfacial shear strength of all alkalized fibers were found to lie within the range of nonalkalized fibers. Laminates were made of alkalized fibers with unsaturated polyester resin, using hand lay‐up and compression moulding. Alkalization of fibers at low concentrations of 1 and 5% resulted in improvements in tensile and fatigue properties of composites made from these fibers, but no such improvements were observed for 10% alkalized fiber composites. The improvements were attributed to improvement in fiber/matrix bonding after this treatment, which was also confirmed by scanning electron microscopy images. No improvement in impact damage tolerance was observed for any of these three alkalized fiber composites. Immersion in distilled water reduced water absorption compared with nonalkalized fiber composites; however, the tensile properties in water were similar to those for nonalkalized fiber composites. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers
Mechanical and thermal properties of rubber composites reinforced by zinc methacrylate and carbon black
Authors: Chae Hee Dong , Basuli Utpal , Lee Ji Hong , Lim Chun Il , Lee Ran Hee , Kim Sung Choul , Jeon Nam Duk , Nah Changwoon 
Published: May 2012

AbstractZinc methacrylate (ZMA) and carbon black (CB) are incorporated into natural rubber/butadiene rubber matrix by direct mixing in a Banbury mixer. Tensile and tear tests showed that CB has a great reinforcing effect on rubber matrix. The results show that the amount of ZMA also plays an important role in mechanical properties. The addition of ZMA resulted in a significant increase of the optimum cure time even at lower loading. Incorporation of ZMA improved mechanical properties, such as tensile modulus and cure reinforcing parameter. The extraordinary improvement in properties is due to the formation of covalent and ionic crosslink. The composite containing only CB shows higher elongation at break, superior tensile strength, and tear strength than ZMA‐filled composites. Reinforcing effect of different composites has also been evaluated using different theoretical model. It has been observed that blowout time became slower and blowout temperature became higher as the ZMA content of the specimen increased. This represents multiple interactions between ZMA and rubber matrix. On the basis of the experimental results, possible mechanisms for reinforcement and microstructure of ZMA/rubber composites have been proposed. Both ZMA and CB provide better thermal stability especially for the composites, where the highest reinforcement effect is observed by mechanical analysis. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers
Plasma Sterilization of Pharmaceutical Products: From Basics to Production
Authors: Denis Benjamin , Steves Simon , Semmler Egmont , Bibinov Nikita , Novak Wenzel , Awakowicz Peter 
Published: May 2012

AbstractFor the first time, a commercial low pressure plasma sterilization system integrated in a pharmaceutical filling line is presented. The route from a laboratory plasma reactor to an industry scale plasma sterilization reactor is shown. Absolutely calibrated measurements (e.g. OES and Langmuir probe) yield to a knowledge transfer from an experimental set‐up to an industrial reactor. Spore count reduction of 4 log in 10 s of Geobacillus stearothermophilus and Bacillus subtilis spores prove the applicability of an industrial grade plasma sterilization reactor for transfer isolators typically used in pharmaceutical filling and packaging lines.magnified image