bluuebunny/crossref_metadata_2025_split huggingface dataset:
Loading of Bacterial Cellulose Aerogels with Bioactive Compounds by Antisolvent Precipitation with Supercritical Carbon Dioxide
Authors: Haimer Emmerich , Wendland Martin , Schlufter Kerstin , Frankenfeld Katrin , Miethe Peter , Potthast Antje , Rosenau Thomas , Liebner Falk 
Published: September 2010

AbstractBacterial cellulose aerogels overcome the drawback of shrinking during preparation by drying with supercritical CO2. Thus, the pore network of these gels is fully accessible. These materials can be fully rewetted to 100% of its initial water content, without collapsing of the structure due to surface tension of the rewetting solvent. This rehydration property and the high pore volume of these material rendered bacterial cellulose aerogels very interesting as controlled release matrices. Supercritical CO2 drying, the method of choice for aerogel preparation, can simultaneously be used to precipitate solutes within the cellulose matrix and thus to load bacterial cellulose aerogels with active substances. This process, frequently termed supercritical antisolvent precipitation, is able to perform production of the actual aerogel and its loading in one single preparation step. In this work, the loading of a bacterial cellulose aerogel matrix with two model substances, namely dexpanthenol and L‐ascorbic acid, and the release behavior from the matrix were studied. A mathematical release model was applied to model the interactions between the solutes and the cellulose matrix. The bacterial cellulose aerogels were easily equipped with the reagents by supercritical antisolvent precipitation. Loading isotherms as well as release kinetics indicated no specific interaction between matrix and loaded substances. Hence, loading and release can be controlled and predicted just by varying the thickness of the gel and the solute concentration in the loading bath.
Cryo‐FIB‐Preparation and Cryo‐SEM Investigation of Gold Nanolayers Used as Absorber for Laser Welding of Polymer Foils
Authors: Neuber M. , Cismak A. , Heilmann A. 
Published: September 2010

AbstractThe morphology of welded polymer foils was investigated by Scanning Electron Microscopy (SEM) using Focused Ion Beam (FIB) technology for cross‐sectional preparation. Due to the sensitive structure of the copolymer Ethylene Tetrafluororethylene (ETFE), FIB preparation and SEM investigation were performed at cryo conditions. A gold nanolayer was used as absorber for the laser beam to weld the transparent copolymer foils. The embedding of the gold nanolayer inside the welding seam and its influence on the mechanical stability of the welding seams was demonstrated.
Polymer Nanostructures by Forced Assembly: Process, Structure, and Properties
Authors: Ponting Michael , Hiltner Anne , Baer Eric 
Published: September 2010

AbstractThe process of micro‐ and nanolayer coextrusion of polymeric systems with good layer uniformity is described. Coextrusion through a series of layer multiplying die elements has enabled the production of films containing tens to thousands of layers with individual layer thicknesses from the micro‐ to the nanoscale. Improvements in layer uniformity are discussed through optimization of layer multiplier die design, selection of viscosity matched polymer systems, and incorporation of surface layer capabilities. Design of ‘uneven’ split layer multiplication dies has enabled the coextrusion of layered films with a wide variety of layer thickness distributions having up to a 10× difference in the individual film layer thicknesses. Coextrusion of layered polymer films with individual layer thicknesses down to the nanoscale has resulted in the production of novel systems with improved properties. Nanolayered polymer films were utilized to develop an all‐plastic polymer laser, to fabricate gradient refractive index lenses, and to investigate gas barrier enhancement of crystalline polymer nanolayers confined to induce a high aspect ratio, in‐plane, single‐crystal‐like lamellar structure.
Extrusion Induced Morphologies and Properties of Layered Block Copolymer/Polystyrene Mixtures
Authors: Adhikari R. , Buschnakowski M. , Lebek W. , Godehardt R. , Michler G. H. , Knoll K. 
Published: September 2010

AbstractUsing transmission electron microscopy (TEM) and tensile testing, we investigated the morphology and the micro‐deformation processes in a new kind of highly asymmetric polystyrene/polybutadiene based triblock copolymer and its blends with general purpose polystyrene (GPPS). The emphasis has been put on the analysis of blends morphology evolved under extrusion conditions and the impact of the later on the micromechanical behaviour of the blends. It was found that the phase separated structures were strongly oriented along the extrusion direction leading to the anisotropic mechanical behaviour. The blends showed more ductile performance and lesser strength on loading the sample perpendicular to the extrusion direction. The ductile to brittle transition was observed when the morphology of the blends was dominated by the glassy phase for 60 wt.‐% GPPS.
Cycloolefin‐Copolymer/Polyethylene (COC/PE) Blend Assists with the Creation of New Articular Cartilage
Authors: Petrtyl M. , Bastl Z. , Krulis Z. , Hulejova H. , Polanska M. , Lisal J. , Danesova J. , Cerny P. 
Published: September 2010

AbstractIt is shown that the initial biomechanical stability of the applied COC/PE blend in the treated tissue locality, the initial integrity of biomaterials substituting the subchondral bone by polymer implant, the initial bearing capacity and the vertical position of these biomaterials have a mayor influence on the regeneration of new articular cartilage and subchondral bone. These aspects are essential for a prosperous treatment of osteochondral defects. Results reveal that the initial biomechanical stiffness of materials (substituting the subchondral bone) has a fundamental influence on both the quality and the quantity of new articular cartilage and subchondral bone. Research is also aimed at the application of suitable biologically tolerated polymer material, its surface modifications, verifications of the vertical position of implants in relation to the articular cartilage surface and ensuring the initial biomechanical stability of the polymer implant.
Solvent Influences the Morphology and Mechanical Properties of Electrospun Poly(L‐lactic acid) Scaffold for Tissue Engineering Applications
Authors: Asran A.Sh. , Salama M. , Popescu C. , Michler G.H. 
Published: September 2010

AbstractElectrospun micro‐ and nanofiber scaffolds have gained interest in biomedical applications, especially in tissue engineering, because they can be used to reproduce the structure of the extracellular matrix (ECM) of natural tissue. The selection of the solvent is an important factor which affects the diameter, the surface morphology and the crystallinity of the electrospun fibers, and, accordingly, their mechanical properties as well as their degradation kinetics. Furthermore, the surface morphology of the electrospun fibres can be controlled by solvent vapour pressure to produce porous structures which might be helpful for cell adhesion and proliferation. In the present work, poly (L‐lactic acid) (PLLA) has been electrospun using solvents with different vapour pressures to investigate the influences of the solvent vapour pressure on morphology, diameter, crystallinity and mechanical properties of the electrospun fiber scaffolds. The results show that the vapour pressure of the solvents (or solvent mixtures) play an important role in the fiber diameter and crystallinity. Furthermore, the crystallinity of the fibers is increased by lowering the vapour pressure of the used solvent. In addition, the mechanical properties (e.g., tensile strength and Young's modulus) are strongly dependent on morphological features such average fibers diameter. The smaller the average diameter, the higher the tensile strength and Young's modulus.
A U.S. survey of patients with Parkinson's disease: Satisfaction with medical care and support groups
Authors: Dorsey E. Ray , Voss Tiffini S. , Shprecher David R. , Deuel Lisa M. , Beck Christopher A. , Gardiner Irenita F. , Coles Margaret A. , Burns Richard S. , Marshall Frederick J. , Biglan Kevin M. 
Published: September 2010

AbstractRelatively little is known about patient satisfaction with Parkinson's disease (PD) care and the use of support groups in the United States. We surveyed members of the Muhammad Ali Parkinson's Disease Registry to assess satisfaction with medical care and to evaluate support group use. Satisfaction was measured on a 5‐point Likert scale, with high satisfaction defined as a four or five. We used multiple logistic regression to identify factors associated with high satisfaction and support group use. The response rate was 38% (726 of 1923). Most (57%) expressed high satisfaction with PD care. Individuals were most satisfied with the time their provider spent with them (61%) and PD education (56%) but least satisfied with prognostic information (35%) and information about non‐drug interventions (28%). Patients seeing a PD specialist were three times more satisfied with their care than those seeing a general neurologist (OR = 3.00, 95% CI: 1.92–4.71; P < 0.0001). Support group use is common, and 61% of survey respondents had attended one at any point. Caucasian race (OR = 2.85, 95% CI: 1.45–5.61), PD duration (OR = 1.05 per year, CI: 1.01–1.10), and PD specialist care (OR = 1.80, CI: 1.16–2.77) were associated with greater support group attendance. Overall, 49% reported high satisfaction with their support group. The greatest concerns were specific needs not being addressed (15%) and insufficient expertise within the group (14%). Most individuals with Parkinson's disease expressed high levels of satisfaction, especially with specialist care. Specialty care and improved education, in the clinic or through support groups, may enhance satisfaction and health care quality. © 2010 Movement Disorder Society
Oral administration of docosahexaenoic acid attenuates colitis induced by dextran sulfate sodium in mice
Authors: Cho Jae Young , Chi Sung‐Gil , Chun Hyang Sook 
Published: September 2010

AbstractScope: Dietary supplementation of n‐3 PUFAs, containing docosahexaenoic acid (DHA), modulates the symptoms of colitis. Hence, we investigated the effects of oral administration of pure DHA and the therapeutic agent sulfasalazine (SAL) on chemically induced colitis in mice, and analyzed the expression levels of DHA‐responsive genes in colonic tissue using cDNA arrays.Methods and results: Colitis in BALB/c mice was induced by feeding 5% dextran sulfate sodium (DSS) in drinking water for 7 days. DHA (30 mg/kg/day, DHA) or SAL (100 mg/kg/day, SAL) was administered orally throughout the treatment along with DSS. The DHA‐treated group showed significant reduction of the weight loss and colon shortening compared to the DSS‐treated colitis group. In contrast, SAL treatment was effective in reducing colon shortening, stool consistency and bleeding scores. DHA and SAL treatments also significantly reduced the changes in inflammation of the colon, and reversed the increase in myeloperoxidase activity induced by DSS. Among DSS‐responsive genes, those for inflammatory cytokines (IL‐1β, CD14 antigen and tumor necrosis factor receptor superfamily, member 1b), membrane remodeling genes (matrix metalloproteinase‐3, ‐10 and ‐13) and acute phase proteins (S100 calcium‐binding protein A8), which were increased by DSS, were downregulated by DHA or SAL treatment.Conclusions: DHA was effective in alleviating DSS‐induced colitis in mice, partly by modulating the expression levels of genes involved in colitis.
The insulin sensitivity response is determined by the interaction between the G972R polymorphism of the insulin receptor substrate 1 gene and dietary fat
Authors: Marín Carmen , Pérez‐Martínez Pablo , Delgado‐Lista Javier , Gómez Purificación , Rodríguez Fernando , Yubero‐Serrano Elena María , García‐Ríos Antonio , Camargo Antonio , Pérez‐Jiménez Francisco , López‐Miranda José 
Published: September 2010

AbstractScope: Insulin resistance, a condition associated with type 2 diabetes mellitus, results from the interaction of environmental and genetic factors. The aim of this study was to explore the influence of the G972R polymorphism at the insulin receptor substrate 1 gene on insulin sensitivity in a healthy young population. Furthermore, we examined whether the presence of this single nucleotide polymorphism (SNP; GR or GG) interacts with dietary fat to modulate insulin sensitivity.Methods and results: Fifty‐nine healthy volunteers consumed three diets during 4 wk each following a randomized crossover design: a saturated fatty acid diet, a low‐fat and high carbohydrate (CHO) diet or a MUFA diet. For each diet, we investigated peripheral insulin sensitivity with the insulin suppression test. Steady‐state plasma glucose and plasma‐free fatty acids concentrations were significantly lower in GR subjects after the intake of a CHO diet, than did homozygous GG subjects (p<0.05). However, no differences were observed after consuming the two other diets.Conclusions: Insulin sensitivity increased in GR subjects for the G972R polymorphism at the insulin receptor substrate 1 gene locus, after intake of a CHO diet. Increased knowledge of how these and other genes influence insulin sensitivity should increase the understanding of personalized nutrition.
N‐acetylcysteine counteracts oxidative stress and prevents hCG‐induced apoptosis in rat Leydig cells through down regulation of caspase‐8 and JNK
Authors: Aggarwal Archana , Misro Man Mohan , Maheshwari Ankur , Sehgal Neeta , Nandan Deoki 
Published: September 2010

AbstractWe have earlier reported that following persistent stimulation with hCG, oxidative stress‐induced apoptosis in rat Leydig cells was mainly achieved through the extrinsic pathway. In the present study, the role of N‐acetylcysteine (NAC) in counteracting the oxidative stress and the mechanisms of inhibition of apoptosis under such conditions were investigated. NAC (1 mM) intervention with repeated hCG stimulation (50 ng/ml, four times, each with 30 min challenge) prevented the decline in Leydig cell viability and the rise in lipid peroxidation and reactive oxygen species. Simultaneously, the activities of the enzymes glutathione‐S‐transferase, catalase, superoxide dismutase and the intracellular glutathione and antioxidant capacity of the treated cells improved significantly. Apoptotic markers Fas, FasL, and caspase‐8, up‐regulated following repeated hCG exposure, were significantly down‐regulated following NAC co‐incubation. While Bcl‐2 expression was fully restored, Bax and caspase‐9 remained unchanged. NAC treatment induced down‐regulation of upstream JNK/pJNK and down‐stream caspase‐3 in the target cells. Taken together, the above findings indicate that NAC counteracted the oxidative stress in Leydig cells induced as a result of repeated hCG stimulation, and inhibited apoptosis by mainly regulating the extrinsic and JNK pathways of metazoan apoptosis. Mol. Reprod. Dev. 77:900–909, 2010. © 2010 Wiley‐Liss, Inc.
Broadening the spectrum of controls for skin biopsy in painful neuropathies
Authors: Herrmann David N. , O'Connor Alec B. , Schwid Steven R. , DA Yuwei , Goodman Andrew D. , Rafferty Jennifer , Donahue Suzanne , Dworkin Robert H. 
Published: September 2010

AbstractEpidermal nerve fiber density (ENFD) is useful in the evaluation of small‐fiber neuropathies (SFSNs). A recent evidence‐based review highlighted the need to broaden the spectrum of ENFD controls to include lower limb pain states other than polyneuropathy. We studied epidermal innervation in multiple sclerosis (MS) and distal lower limb burning pain (DLLBP). Distal‐leg ENFD/morphology in MS DLLBP patients did not differ significantly from that of healthy controls. This study extends the range of ENFD controls and further supports use of ENFD assessment in SFSN. Muscle Nerve, 2010
Proposal for a modified grading system based on mitotic index and Bcl2 provides objective determination of clinical outcome for patients with breast cancer
Authors: Abdel‐Fatah Tarek MA , Powe Desmond G , Ball Graham , Lopez‐Garcia Maria A , Habashy Hany O , Green Andrew R , Reis‐Filho Jorge S , Ellis Ian O 
Published: September 2010

AbstractWe hypothesized that the interaction between mitotic index (M) and Bcl2 could accurately discriminate between low‐ and high‐grade breast cancer (BC) and provide a more objective measure of clinical outcome than histological grade, especially for patients with intermediate histological grade (G2), small size or oestrogen receptor (ER)‐negative cancers. A well‐characterized series of 1650 BCs with long‐term follow‐up was subjected to immunohistochemical analysis for Bcl2. Mitotic index (M) was assessed according to Nottingham Grading System (NGS) guidelines: M1: < 10 mitoses; M2: 10–18 mitoses; M3: > 18 mitoses. Results were validated in an independent series of patients (n = 245) uniformly treated with adjuvant anthracycline‐based chemotherapy. Subsequently, BCs were classified according to the combined M/Bcl2 profile and compared with NGS. Multivariate Cox regression models using validated prognostic factors demonstrated that the subgroups defined by M/Bcl2 profile remained significantly associated with patients' outcome but also performed better than lymph node status and tumour size. Incorporation of the M/Bcl2 profile into the Nottingham Prognostic Index (NPI) reclassified twice as many patients into the excellent prognosis group, potentially improving decision‐making and sparing patients unneeded systemic adjuvant therapy. Patients with M2–3/Bcl2− and M3/Bcl2+ (high risk) had a two‐ to three‐fold increased risk of recurrence when treated with either adjuvant hormone therapy or anthracycline‐based chemotherapy compared with those with M1/Bcl2 ± and M2/Bcl2+ (low risk) [HR = 3.4 (2.8–5.6); p < 0.0001 and HR = 2.3 (1.2–4.3); p = 0.0009]. In conclusion, a grading system defined by mitotic counting and Bcl2 expression accurately reclassified patients with NGS‐G2, small tumour size or ER‐negative cancers into two groups: low risk (NGS‐G1‐like) versus high risk (NGS‐G3‐like) of BC mortality and recurrence, improving prognosis and therapeutic planning. Copyright © 2010 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Validated TLC method for simultaneous quantitation of kutkoside and picroside‐I from Kutki extract
Authors: Gaikwad P. S. , Bhope S. G. , Kuber V. V. , Patil M. J. 
Published: September 2010

AbstractIntroduction – The two iridoid glycosides kutkoside and picroside‐I are the active hepatoprotective principles of Picrorhiza kurroa Royle ex Benth (Scrophulariaceae), commonly known as Kutki. Quantitation of these phytoconstituents is important for the routine quality control of Kutki extract.Objective – To develop and validate a simple, precise and rapid thin‐layer chromatography (TLC) method for the simultaneous quantitation of kutkoside and picroside‐I in Kutki extract.Methodology – The analysis was performed on a TLC precoated silica gel 60 F254 plate with ethyl acetate:methanol:glacial acetic acid:formic acid (25:5:1:1, v/v/v/v) as mobile phase. Densitometric evaluation of kutkoside and picroside‐I was carried out at 265 nm and the mobile phase showed good resolution with Rf values 0.42 ± 0.03 and 0.61 ± 0.03 for kutkoside and picroside‐I, respectively. The method was validated in terms of specificity, linearity, accuracy and precision.Results – The content of kutkoside and picroside‐I was found to be 2.18 and 1.90%, respectively, and was comparable with those obtained by HPLC. The linearity was found to be in the range of 80–480 ng/spot for both kutkoside and picroside‐I. The average recovery values were found to be 96.5 and 96.0% for kutkoside and picroside‐I, respectively.Conclusion – The developed method was found to be relatively simple, precise and reproducible for the simultaneous quantitation of kutkoside and picroside‐I. The method does not employ any derivatisation procedure and can be used as a quality control tool for the routine analysis of commercial Kutki extracts. Copyright © 2010 John Wiley & Sons, Ltd.
Synchronous fluorescence determination of phytic acid in FOODSTUFFS and urine based on replacement reaction
Authors: Cao Shuhong , Dong Nian , Chen Jingwen 
Published: September 2010

AbstractIntroduction – Phytic acid is a ubiquitous and abundant natural component in many plant seeds, fruits and vegetables. Its biological and pharmaceutical functions are still controversial. The examination on the level of phytic acid in foodstuffs and urine can provide valuable information for its dietary intake and metabolism.Objective – To develop a sensitive and reliable synchronous fluorescence protocol for determination of phytic acid in selected foodstuffs and human urine.Methodology – Phytic acid efficiently catches Cu2+ ion in previously prepared CuII‐2,2′‐bipyridine complex in aqueous solution, releasing the fluorescent 2,2′‐bipyridine molecule and recovering synchronous fluorescence. The recovered fluorescence is proportional to the added phytic acid, by which the levels of phytic acid in the selected foodstuffs and human urine are quantified.Results – A calibration curve with a regression equation of If = 37.745 + 39.245c (R2 > 0.9988) showed good linearity over the range 0.18–17.50 mg/L phytic acid. The relative standard deviation at 95% confidence degree was less than 2.04% (n = 5), indicating that the procedures are reproducible. The detection and quantification limit of phytic acid were estimated to be 0.12 and 0.18 mg/L, respectively. By the proposed method, phytic acid in the selected foodstuffs and urine was determined to be 3.25–16.76 and 0.43–1.21 mg/L with recoveries of 96.8%–105.6% and 95.1%–104.2%, respectively. The results are in good agreement with those obtained by the reported HPLC technique.Conclusion – The developed method is sensitive, reliable and economical, which permits its practical application in quantitative analyses of trace phytic acid in foodstuffs and urine. Copyright © 2010 John Wiley & Sons, Ltd.
Carbon dioxide‐induced crystallization in poly(L‐lactic acid) and its effect on foam morphologies
Authors: Liao Xia , Nawaby Arghavan Victoria , Whitfield Pamela S 
Published: September 2010

AbstractThe effect of carbon dioxide (CO2) on the physical properties of poly(L‐lactic acid) (PLLA) and on the formation of crystalline domains was investigated. The presence of CO2 in the matrix was found to induce crystallization in PLLA, with the crystallinity increasing with increasing CO2 pressure. The combination of saturation conditions and formation of crystalline domains was studied for its effect on the formation of porous morphologies in PLLA. Moreover, the effect of CO2 on PLLA properties and formation of porous structures was further exploited by first creating crystalline domains in samples using CO2 at various pressures at 25 °C and then re‐saturating the same samples with CO2 at a constant pressure of 2.8 MPa and 0 °C. This paper reports on the solubility of CO2 at 25 and 0 °C in PLLA, crystallization and subsequent effect on foam morphologies when processed using different saturation cycles. Unique and intriguing morphologies were obtained by specifically controlling the properties of PLLA. Copyright © 2010 Crown in the right of Canada. Published by John Wiley & Sons, Ltd