bluuebunny/crossref_metadata_2025 huggingface dataset:
Solubility, salivary sorption and degree of conversion of dimethacrylate‐based polymeric matrixes
Authors: Gonçalves Luana , Filho Jaime D. N. , Guimarães José G. A. , Poskus Laiza T. , Silva Eduardo M.
Published: October 2007

This study investigated the relationship between the solubility, salivary sorption, and degree of conversion of dimethacrylate‐based polymeric matrixes. Six polymeric matrixes produced by mixing bis‐GMA, TEGDMA and UDMA dimethacrylate monomers were studied. Photoactivation was induced by camphoroquinone/ethyl N,N‐dimethyl‐4‐aminobenzoate. The specimens were light‐cured using an irradiance of 850 mW/cm2 for 20 s. The solubility and sorption (μg/mm3) were measured after immersion in artificial saliva (neutral pH) for 7 days. The degree of conversion (%) was obtained by using a FT‐IR spectrometer equipped with an attenuated total reflectance crystal (ATR). The degree of conversion varied from 39.15 ± 6.30 to 65.57± 4.80, and was influenced by the viscosity of the monomers present in the polymeric matrixes. The solubility of polymeric matrixes varied between 13.64 ± 0.39 and 25.08 ± 0.83, and was strongly influenced by the degree of conversion (Pearson, r = −0.9587, p < 0.01). No correlation was found between salivary sorption and the degree of conversion (p = 0.3918). Salivary sorption was only dependent on the chemical and physical structures of the monomers presented in the polymeric matrixes. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008
Synthesis and properties of waterborne polyurethane hydrogels for wound healing dressings
Authors: Yoo Hye‐Jin , Kim Han‐Do
Published: October 2007

To accomplish ideal wound healing dressing, a series of waterborne polyurethane (WBPU) hydrogels based on polyethylene glycol (PEG) were synthesized by polyaddition reaction in an emulsion system. The stable WBPU hydrogels which have remaining weight of above 85% were obtained. The effect of the soft segment (PEG) content on water absorbability of WBPU hydrogels was investigated. Water absorption % and equilibrium water content (%) of the WBPU hydrogel significantly increased in proportion to PEG content and the time of water‐immersion. The maximum water absorption % and equilibrium water content (%) of WBPU hydrogels containing various PEG contents were in the range of 409–810% and 85–96%, respectively. The water vapor transmission rate of the WBPU hydrogels was found to be in the range of 1490–3118 g/m2/day. These results suggest that the WBPU hydrogels prepared in this study may have high potential as new wound dressing materials, which provide and maintain the adequate moist environment required to prevent scab formation and dehydration of the wound bed. By the wound healing evaluation using full‐thickness rat model experiment, it was found that the wound covered with a typical WBPU hydrogel (HG‐78 sample) was completely filled with new epithelium without any significant adverse reactions. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008
Local tissue reaction and differentiation of the prosthesis‐specific antibody response following functional implantation of vascular grafts in pigs
Authors: Zippel Roland , Wilhelm Lutz , Hoene Andreas , Walschus Uwe , Ueberrueck Torsten , Schlosser Michael
Published: October 2007

The study was aimed at investigating the local tissue reactions through a histological examination of β‐1‐integrin expression and neointima formation, and humoral immune responses by detection of prosthesis‐specific antibodies, after functional implantation of vascular prostheses. In three groups of pigs, the infrarenal aorta was replaced with segments of collagen‐impregnated Dacron®‐prostheses: M‐prosthesis—medium primary porosity, double velour layer, crimping; C‐prosthesis—low primary porosity, no velour, crimping; T‐prosthesis—high primary porosity, no velour, no crimping. For each prosthesis type, one series with four animals was used for examining the tissue reactions, and a second series with eight animals was used to study the antibody response, both until 116 days postoperative. In the first three weeks, the M‐prosthesis caused the highest tissue reactions and the highest antipolyester antibodies, but the lowest anticollagen antibodies, whereas the T‐prosthesis caused the highest anticollagen antibodies, but the least tissue response and antipolyester antibodies in the early phase. On day 116, the C‐prosthesis caused the highest tissue reactions and highest polyester‐specific antibodies. These results indicate a possible association between local inflammatory reactions and humoral immune responses, influenced by properties of vascular grafts. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008
Comparison of cobalt chromium, ceramic and pyrocarbon hemiprostheses in a rabbit model: Ceramic leads to more cartilage damage than cobalt chromium
Authors: Jung Martin , Wieloch Peter , Lorenz Helga , Gotterbarm Tobias , Veyel Katrin , Daniels Mark , Martini Abdul Kader , Daecke Wolfgang
Published: October 2007

Cartilage wear after hemiarthroplasty remains a problem in orthopedic surgery. The main cause of cartilage wear, apart from incongruency of the joint partners, is generally considered to be the tribology of the material surfaces. This study evaluates in 27 rabbits the degree of cartilage wear of the tibia plateau after hemiarthroplasty with proximal interphalangeal prostheses made of three different materials [cobalt chromium (CoCr), pyrocarbon (PyCa), and ceramic (Cer)]. Three months after hemiarthroplasty, the articulating tibial cartilage was histomorphologically examined and degenerative damage was graded using the modified Mankin score. The mechanical capacity of the cartilage was assessed by stress relaxation testing. The biomechanical properties of the cartilage were significantly superior in the CoCr group as compared with the Cer group (p < 0.03), indicating less damage to the articulating cartilage surface. The Mankin score showed significantly lower values in the CoCr compared with Cer group (p = 0.011), whereas no differences were found between PyCa and CoCr or PyCa and Cer. In contrast to earlier reports, in this hemiarthroplasty model, the CoCr alloy showed less cartilage damage than a ceramic surface. Further, in vivo experiments are necessary to elucidate the controversial issue of the most suitable material for hemiarthroplasty. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008
Get sustained growth by savvy portfolio management
Authors: Sanwal Anand
Published: October 2007

Your firm's corporate portfolio can play a key role in achieving an elusive goal: sustained growth. But it's a tough balancing act. The author gives you a road map for adroitly managing your corporate portfolio and achieving solid results. © 2007 Wiley Periodicals, Inc.
Saving cash: How to outnegotiate a leasing company
Authors: Contino Richard M.
Published: October 2007

Many companies have a lot of cash tied up in leasing equipment. But there are ways to save a lot of money if you know how to outnegotiate a leasing company. The secret is to put together a comprehensive set of written bidding guidelines, reveals the author of this article. And he shows you how to do it. © 2007 Wiley Periodicals, Inc.
The lessons of Adelphia's cash fraud
Authors: Johnson Leigh Redd , Rudolph Holly R.
Published: October 2007

By using a complex centralized cash management system for Adelphia, John and Timothy Rigas systematically looted the company over a prolonged period. It was one of the most massive cases of corporate financial fraud to date. But what lessons does it teach us about cash management? © 2007 Wiley Periodicals, Inc.
Capital budgeting: Problems and new approaches
Authors: Sagner James S.
Published: October 2007

Capital budgeting techniques using discounted cash flow calculate the present value of future flows, compared to the cash outflows or the investment required to fund a capital project. But companies are reluctant to commit funds to capital projects these days—probably because of disappointing past returns. The author explains current capital budgeting practices and reviews new approaches that may offer some solutions. He also offers a handy quick checklist for capital budgeting decisions. © 2007 Wiley Periodicals, Inc.
Recent SEC/PCAOB developments
Authors: Ciesielski Jack T. , Weirich Thomas R.
Published: October 2007

As we approach another SEC/PCAOB conference, the authors review the developments of the last conference and briefly ponder which issues will be hot at this year's conference. © 2007 Wiley Periodicals, Inc.
Integrated information systems: SAS 94 and auditors
Authors: Pathak Jagdish , Lind Mary R.
Published: October 2007

Statement on Auditing Standards No. 94 (SAS 94) gives guidance to auditors on how IT impacts internal control—and it affects how auditors get their understanding of internal control and assess control risk. The authors discuss the background of these issues, describe the major changes of SAS 94, and give tips on implementing it. © 2007 Wiley Periodicals, Inc.
Increased adipogenesis of osteoporotic human‐mesenchymal stem cells (MSCs) characterizes by impaired leptin action
Authors: Astudillo Pablo , Ríos Susana , Pastenes Luis , Pino Ana María , Rodríguez J. Pablo
Published: October 2007

The bone marrow contains mesenchymal stem cells (MSCs) that differentiate to the osteogenic and adipogenic lineages. The fact that the decrease in bone volume of age‐related osteoporosis is accompanied by an increase in marrow adipose tissue implies the importance that the adipogenic process may have in bone loss. We previously observed that MSCs from control and osteoporotic women showed differences in their capacity to differentiate into the osteogenic and adipogenic pathways. In vitro studies indicate that bone marrow stromal cells are responsive to leptin, which increases their proliferation, differentiation to osteoblasts, and the number of mineralized nodules, but inhibits their differentiation to adipocytes. The aim of the present report was to study the direct effect of leptin on control and osteoporotic MSCs analyzing whether the protective effect of leptin against osteoporosis could be expressed by inhibition of adipocyte differentiation. MSCs from control, and osteoporotic donors were subjected to adipogenic conditions, in the absence or in the presence of 62.5 nM leptin. The number of adipocytes, the content of PPARγ protein, and mRNA, and leptin mRNA were measured by flow cytometry, Western blot, and RT‐PCR, respectively. Results indicate that control and osteoporotic MSCs differ in their adipogenic potential as shown by expression of active PPARγ protein. Leptin exerted an antiadipogenic effect only on control MSCs increasing the proportion of inactive phosphorylated PPARγ protein. Finally, results obtained during adipogenesis of osteoporotic cells suggest that this process is abnormal not only because of increased adipocyte number, but because of impaired leptin cells response. J. Cell. Biochem. 103: 1054–1065, 2008. © 2007 Wiley‐Liss, Inc.
Flavonoids‐induced accumulation of hypoxia‐inducible factor (HIF)‐1α/2α is mediated through chelation of iron
Authors: Park Sung‐Soo , Bae Insoo , Lee Yong J.
Published: October 2007

Hypoxia‐inducible factor‐1 alpha (HIF‐1α) is the regulatory subunit of the heterodimeric transcription factor HIF‐1 that is the key regulator of cellular response to low oxygen tension. Under normoxic conditions, HIF‐1α is continuously degraded by the ubiquitin‐proteasome pathway through pVHL (von Hippel–Lindau tumor suppressor protein). Under hypoxic conditions, HIF‐1α is stabilized and induces the transcription of HIF‐1 target genes. Quercetin, a flavonoid with anti‐oxidant, anti‐inflammatory, and kinase modulating properties, has been found to induce HIF‐1α accumulation and VEGF secretion in normoxia. In this study, the molecular mechanisms of quercetin‐mediated HIF‐1α accumulation were investigated. Previous studies have shown that, in addition to being induced by hypoxia, HIF‐1α can be induced through the phosphatidylinositol 3‐kinase (PI3K)/Akt and p53 signaling pathways. But our study revealed, through p53 mutant‐type as well as p53 null cell lines, that neither the PI3K/Akt nor the p53 signaling pathway is required for quercetin‐induced HIF‐1α accumulation. And we observed that HIF‐1α accumulated by quercetin is not ubiquitinated and the interaction of HIF‐1α with pVHL is reduced, compared with HIF‐1α accumulated by the proteasome inhibitor MG132. The use of quercetin's analogues showed that only quercetin and galangin induce HIF‐1/2α accumulation and this effect is completely reversed by additional iron ions. This is because quercetin and galangin are able to chelate cellular iron ions that are cofactors of HIF‐1/2α proline hydroxylase (PHD). These data suggest that quercetin inhibits the ubiquitination of HIF‐1/2α in normoxia by hindering PHD through chelating iron ions. J. Cell. Biochem. 103: 1989–1998, 2007. © 2007 Wiley‐Liss, Inc.
Mutational robustness and geometrical form in protein structures
Authors: Hartling Julia , Kim Junhyong
Published: October 2007

Theoretical studies of RNA and lattice protein models suggest that mutationally robust or the so‐called designable phenotypes tend to have special geometric features such as being more compact and more geometrically regular. Such geometrical forms have been also linked to speed of folding and stability properties that may also assist in promoting mutational robustness. Here we test these theoretical predictions on a non‐redundant collection of 2,660 experimentally determined structures from the PDB (Protein Data Bank) and CATH (Class Architecture Topology Homologous superfamily) database. We first developed an index summarizing the geometrical regularity of the structures and then used this index to show that the statistical pattern of empirical data is consistent with the theoretical predictions relating geometry to mutational robustness. Mutationally robust proteins tend to be more symmetric and compact. But, the relationship between compactness and robustness cannot be explained simply by the geometrical packing of individual amino acids in proteins; rather, it is the property of the whole system that is related to the statistical characteristics of the folding landscape. Finally, we hypothesize that a triplet relationship between mutational robustness, stability and form is a general properties of objects that optimize real‐valued relationships between sequences and discrete structures. J. Exp. Zool. (Mol. Dev. Evol.) 310B:216–226, 2008. © 2007 Wiley‐Liss, Inc.
Changes of the bone mineral density in proximal femur following total hip resurfacing arthroplasty in osteonecrosis of femoral head
Authors: Lian Yong‐yun , Pei Fu‐xing , Yoo Myung‐chul , Cheng Jing‐qiu , Fatou Camara‐yagouba
Published: October 2007

Total hip resurfacing arthroplasty (THRA) is being performed with increasing frequency for osteonecrosis of femoral head (ONFH). To evaluate femoral bone remodeling in ONFH after THRA and determine the impact of stem‐neck angle (SNA) of inserted femoral component on bone remodeling, we monitored the changes in BMD in proximal femur in 23 patients with ONFH after surgery. Patients were divided into group A (SNA ≥ 5°) and group B (SNA < 5°). The BMD was measured in seven Gruen zones and two neck zones using dual‐energy X‐ray absorptiometry preoperatively, then at 3, 6, 12, and 24 months after surgery. At all ROIs, the BMD decreased significantly by 3 months postoperatively. The BMD ceased to decrease and reversed by 6 months. The BMD in neck increased significantly in group A, compared with group B at 24 months. The BMD increased 2% at ROI1 at 24 months in both groups, and at ROI7, the BMD in group A reversed to baseline value by 6 months and increased 5.81% at 24 months. These findings implied that the bone stock of proximal femur in ONFH can be well reserved after total hip resurfacing arthroplasty with valgus positioning of the femoral component. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:453–459, 2008
Quantitative characterization of gait kinematics in patients with hallux rigidus using the Milwaukee foot model
Authors: Canseco Karl , Long Jason , Marks Richard , Khazzam Michael , Harris Gerald
Published: October 2007

The purpose of this study was to provide a quantitative analysis of the changes that occur in the foot and ankle during the gait of patients with hallux rigidus. Using a 15‐camera Vicon Motion Analysis System, gait analysis was conducted on a population of 22 patients with hallux rigidus and compared to that of 25 healthy ambulators. Weight‐bearing radiographs were measured to index marker positions to underlying bony anatomy. The Milwaukee Foot Model was used to perform three‐dimensional analysis of dynamic foot and ankle motion, and temporal–spatial parameters were also calculated. Values were compared to controls using unpaired parametric methods (Student t‐test, p < 0.002). The hallux rigidus population showed significant alterations in gait patterns as compared to controls in various planes in all segments (hallux, forefoot, hindfoot, and tibia) of the foot and ankle, particularly in the range of motion of the hallux and the forefoot. Prolonged stance phase was also observed. As reports regarding the quantitative study of the multisegment foot and ankle are limited, this study was useful in providing characterization of gait patterns in patients with hallux rigidus. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:419–427, 2008
Navigated lower limb axis measurements: Influence of mechanical weight‐bearing simulation
Authors: Kendoff Daniel , Board Timothy N. , Citak Musa , Gardner Michael J. , Hankemeier Stefan , Ostermeier Sven , Krettek Christian , Hüfner Tobias
Published: October 2007

Successful outcomes following high tibial osteotomy (HTO) require precise realignment of the mechanical axis of the lower extremity. The inability to accurately assess the weight‐bearing axis intraoperatively may account for inappropriate degrees of correction with the osteotomy. We tested the hypothesis that axial loading of the limb affects alignment during an HTO procedure. A custom mechanical load apparatus was developed to simulate weight‐bearing conditions intraoperatively. Fixation to the trunk was achieved by supraacetabular pins and an external fixation device, which allowed the pelvis to be rigidly fixed relative to the apparatus while axial load was applied to the foot. Ten fresh cadavers were used for testing. The baseline mechanical axis was determined by a navigation system. HTO was then performed, and varying degrees of valgus correction were obtained and stabilized. For each correction, one quarter, one half, or full body weight was applied axially to the foot, and the axis deviation was measured. Subsequently, the MCL was sequentially released to determine the effect of ligament incompetence. Prior to osteotomy, load application did not produce significant axis deviations. Following osteotomy, the mechanical axis deviation shifted significantly in all trials, increasing as load magnitude and degree of correction increased. With complete sectioning of the MCL, a further significant shift in the axis occurred. Deviations of mechanical axis occur on weight bearing in lower limbs following HTO. These shifts must be considered and possibly quantified to achieve the desired axis correction and maximize the chance at a successful long term outcome. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:553–561, 2008
In vivo release of the antimicrobial peptide hLF1‐11 from calcium phosphate cement
Authors: Stallmann Hein P. , Roo Ronald de , Faber Chris , Amerongen Arie V. Nieuw , Wuisman Paul I.J.M.
Published: October 2007

We studied the release of human lactoferrin 1‐11 (hLF1‐11), a potent antimicrobial peptide, in an animal model. Calcium phosphate cement with 50 mg/g hLF1‐11 was injected into the femoral canal of 12 rabbits. One, 3, and 7 days later, four animals were terminated, and the femora excised. Sections of bone and cement were removed for histological analysis. We used liquid chromatography‐mass spectrometry/mass spectrometry for semiquantitative determination of the hLF1‐11 concentration. Blood samples were drawn for leukocyte count and differentiation to identify a potential immunomodulating effect of hLF1‐11. After an initial burst release, the hLF1‐11 concentration in cement and bone decreased steadily. This in vivo release profile is consistent with earlier in vitro studies. Tissue ingrowth into the cement, without signs of inflammation or necrosis, was observed. Leukocytosis or a shift in leukocyte differentiation did not occur. The carrier released over 99% of the hLF1‐11, resulting in peak concentrations at the cement–bone interface. This indicates that hLF1‐11 could become a valuable prophylactic agent in osteomyelitis treatment. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:531–538, 2008
Induction of chondrogenesis and superficial zone protein accumulation in synovial side population cells by BMP‐7 and TGF‐β1
Authors: Yamane Shintaro , Reddi A. Hari
Published: October 2007

Synovial cells are known to contain a sub‐population of cells with multipotent differentiating capacity including chondrocytes. However, the stem/progenitor cells in synovial cells have not been well characterized. Stem/progenitor cells can exclude Hoechst 33342 dye, and the cell fraction with this property is called “side population (SP).” SP cells are present in many adult tissues. The aim of this investigation was to identify, isolate, and characterize SP cells from bovine synovium. Hoechst dye efflux and fluorescence activated cell sorting showed that synovial cells contained 0.60% SP cells. In the presence of verapamil, an inhibitor of ABC transporters critical for the dye efflux property, the SP cell fraction was not observed, indicating the critical role of ABC transporters. Isoforms of ABC transporters (ABCG2 and ABCB1 mRNA) were highly expressed in SP cells derived from the synovial cells by real‐time RT‐PCR analysis. Bone morphogenetic protein‐7 (BMP‐7) induced type II collagen mRNA expression characteristic of chondrogenesis in articular cartilage with both SP and non‐SP cells. In addition, expression of SZP mRNA, a marker of the surface layer of articular cartilage, was significantly up‐regulated by BMP‐7, and the protein accumulation of SZP was stimulated by both BMP‐7 and TGF‐β1. Thus, synovial cells contain ABC transporter‐dependent SP cells. These findings demonstrate that side population cells of synovium differentiate toward an articular chondrocyte phenotype of the surface layer and have direct implications for tissue engineering and regeneration of articular cartilage. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:485–492, 2008
A rapid and sensitive UPLC‐ESI MS method for analysis of isofraxidin, a natural antistress compound, and its metabolites in rat plasma
Authors: Sun Hui , Lv Haitao , Zhang Yanmei , Wang Xijun , Bi Kaishun , Cao Hongxin
Published: October 2007

Isofraxidin is one of the main bioactive constituents in the root of Acanthopanax senticosus, which has antifatigue, antistress, and immuno‐accommondating effects. In this study, an ultraperformance LC (UPLC)‐ESI MS method was developed for analyzing isofraxidin and its metabolites in rat plasma. The analysis was performed on a UPLC coupled with ESI MS (quadropole MS tandem TOF MS). The lower LOD (LLOD) for isofraxidin was 0.25 ng/mL, the intraday precision was less than 10%, the interday precision was less than 10%, and the extraction recovery was more than 80%. Isofraxidin and two metabolites (M1 and M2) were detected in rat plasma after oral administration of isofraxidin, and the molecular polarities of M1 and M2 were both increased compared to isofraxidin. The metabolites were identified as 5,6‐dihydroxyl‐7‐methoxycoumarin and 5‐hydroxyl‐6,7‐dimethoxycoumarin when subjected to parent ion spectra, product ion spectra, and extract mass and element composition analyses.
Development of an HPLC method for the determination of salidroside in beagle dog plasma after administration of salidroside injection: Application to a pharmacokinetics study
Authors: Mao Yu , Zhang Xinrong , Zhang Xiaodong , Lu Guocai
Published: October 2007

A simple RP‐HPLC method was established for the determination of salidroside in dog plasma. Salidroside is one of the most active ingredients of Rhodiola L. The method had within‐run precision values in the range of ± 2.3 to ± 9.1% (n = 5) and between‐run precision in the range of ± 3.2 to ± 9.8%. A simple protein precipitation for salidroside extraction was processed using ACN at precipitant‐to‐plasma volume ratio (P–P ratio) of 3:2. The extraction recoveries of salidroside at seven concentrations were higher than 63.2%. There was a linear relationship between chromatographic area and concentration over the range of 0.83–520 μg/mL for salidroside in plasma (R = 0.9926). The LOQ (S/N = 10) of the method was 0.83 μg/mL. The method was applied in a study of the pharmacokinetics of salidroside injection in six beagle dogs. The major pharmacokinetic parameters of Cmax, AUC0–24, AUC0–∞, and t1/2 of salidroside in beagle dogs after i.v. administration of a single 75 mg/kg (5 mL/kg) dose were 96.16 ± 8.59 μg/mL, 180.3 ± 30.6 μg·h/mL, 189.3 ± 32.1 μg·h/mL, and 2.006 ± 0.615 h, respectively.
Separation of nucleic acid precursors on an amphoteric surfactant modified monolith using combined eluent flow, pH and concentration gradient
Authors: Nesterenko Ekaterina P. , Guivarc'h Céline , Duffy Cepta , Paull Brett
Published: October 2007

An RP monolithic column coated with an amphoteric carboxybetaine type surfactant has been used with a combined triple eluent concentration, pH and flow gradient ion chromatography technique for the simultaneous separation of up to 18 nucleotides, nucleosides and nucleobases. The separation of up to eight precursors on a 1 cm long monolithic microcolumn using the combined gradient approach is also shown. The method was applied to the separation of the above nucleic acid precursors in perchloric acid extracts of yeastolates samples.
Separation behavior of electron‐beam curing derived, acrylate‐based monoliths
Authors: Bandari Rajendar , Elsner Christian , Knolle Wolfgang , Kühnel Christa , Decker Ulrich , Buchmeiser Michael R.
Published: October 2007

Electron beam (EB) curing‐derived monolith materials were prepared from ethyl methacrylate (EMA), trimethylolpropane triacrylate (TMPTA), 2‐propanol, 1‐dodecanol, and toluene within the confines of 3 mm×100 mm id glass columns, applying a total dose of 22 kGy for curing. Monolithic columns were checked for their separation behavior for selected dansylated (DNS)‐amino acids as well as for cyclophilin 18. Their separation performance was compared to that of a C18‐modified silica‐based rigid rod (Chromoliths®). In the separation of dansylated amino acids, retention times were reduced on EB‐derived columns, where the peak resolution was significantly better than on a Chromolith®. This finding was attributed to a larger fraction of small pores (< 2.15 nm) in the EB curing‐derived monoliths. Finally, EB curing‐derived monoliths have been used to separate cyclophilin 18 from crude cell lysis mixtures.
Evaluation of photografted charged sites within polymer monoliths in capillary columns using contactless conductivity detection
Authors: Connolly Damian , O'Shea Vincent , Clark Paul , O'Connor Brendan , Paull Brett
Published: October 2007

Capacitively coupled contactless conductivity detection (C4D) is presented as a novel and versatile means of visualising discrete zones of charged functional groups grafted onto polymer based monoliths. Monoliths were first formed within 100 μm UV‐transparent fused silica capillaries. Photografting methods were subsequently used to graft a charged functional monomer, 2‐acrylamido‐2‐methyl‐1‐propanesulfonic acid, onto discrete regions of the monolith using a photomask. Post‐modification monolith evaluation involves scanning the C4D detector along the length of the monolith to obtain a profile of the exact spatial location of grafted charged functionalities with millimetre accuracy. The methodology was extended to the visualisation of several zones of immobilised protein (bovine serum albumin) using photografted azlactone groups to enable covalent attachment of the protein to the monolith at precise locations along its length. In addition, the extent of non‐specific binding of protein to the ungrafted regions of the monolith due to hydrophobic interactions could be monitored as an increase in background conductivity of the stationary phase. Finally, the technique was cross‐validated using digital photography in combination with a UV light source by immobilising green fluorescent protein in discrete zones and comparing the results obtained using both complementary techniques.
Thermal decomposition reaction and a comprehensive kinetic model of dimethyl ether
Authors: Zhao Zhenwei , Chaos Marcos , Kazakov Andrei , Dryer Frederick L.
Published: October 2007

The unimolecular decomposition reaction of dimethyl ether (DME) was studied theoretically using RRKM/master equation calculations. The calculated decomposition rate is significantly different from that utilized in prior work (Fischer et al., Int J Chem Kinet 2000, 32, 713–740; Curran et al., Int J Chem Kinet 2000, 32, 741–759). DME pyrolysis experiments were performed at 980 K in a variable‐pressure flow reactor at a pressure of 10 atm, a considerably higher pressure than previous validation data. Both unimolecular decomposition and radical abstraction are significant in describing DME pyrolysis, and hierarchical methodology was applied to produce a comprehensive high‐temperature model for pyrolysis and oxidation that includes the new decomposition parameters and more recent small molecule/radical kinetic and thermochemical data. The high‐temperature model shows improved agreement against the new pyrolysis data and the wide range of high‐temperature oxidation data modeled in prior work, as well as new low‐pressure burner‐stabilized species profiles (Cool et al., Proc Combust Inst 2007, 31, 285–294) and laminar flame data for DME/methane mixtures (Chen et al., Proc Combust Inst 2007, 31, 1215–1222). The high‐temperature model was combined with low‐temperature oxidation chemistry (adopted from Fischer et al., Int J Chem Kinet 2000, 32, 713–740), with some modifications to several important reactions. The revised construct shows good agreement against high‐ as well as low‐temperature flow reactor and jet‐stirred reactor data, shock tube ignition delays, and laminar flame species as well as flame speed measurements. © 2007 Wiley Periodicals, Inc. Int J Chem Kinet 40: 1–18, 2008
Kinetics of the sulfate radical‐mediated photo‐oxidation of humic substances
Authors: Gara Pedro M. David , Bosio Gabriela N. , Gonzalez Mónica C. , Mártire Daniel O.
Published: October 2007

The kinetics of the aqueous phase reaction of sulfate radicals with commercial humic acids and with organic matter extracted from vermicompost (VC) was studied by flash‐photolysis. The results can be interpreted by a mechanism that in a first step considers the reversible binding of the sulfate radicals by the humic substances. Both the bound and free sulfate radicals decay to oxidized products. From experiments performed with Aldrich humic acids in the temperature range from 283 to 303 K, the enthalpy change associated with the binding process was estimated to be −(36 ± 11) kJ mol−1. © 2007 Wiley Periodicals, Inc. Int J Chem Kinet 40: 19–24, 2008
Autocatalytic oxidation of β‐alanine by peroxomonosulfate in the presence of copper(II) ion
Authors: Kannan R. Sayee , Easwaramoorthy D. , Vijaya K. , Ramachandran M. S.
Published: October 2007

Kinetics and mechanism of oxidation of β‐alanine by peroxomonosulfate (PMS) in the presence of Cu(II) ion at pH 4.2 (acetic acid/sodium acetate) has been studied. Autocatalysis was observed only in the presence of copper(II) ion, and this was explained due to the formation of hydroperoxide intermediate. The rate constant for the catalyzed (k) and uncatalyzed (k) reaction has been calculated. The kinetic data obtained reveal that both the reactions are first order with respect to [PMS]. k values initially increase with the increase in [β‐alanine] and reach a limiting value, but k values decrease with the increase in [β‐alanine]. k values increase linearly with the increase in [Cu(II)], whereas k values increase with [Cu(II)]2. Furthermore, k values are independent of [acetate], but k values decrease with the increase in acetate. A suitable mechanism has been proposed to explain the experimental observation. The reaction has been studied at different temperatures, and the activation parameters are calculated. © 2007 Wiley Periodicals, Inc. Int J Chem Kinet 40: 44–49, 2008
Experimental and modeling study of the autoignition of cyclopentene
Authors: Yahyaoui M. , Hakka M. H. , Glaude P. A. , Battin‐Leclerc F.
Published: October 2007

Ignition delay times of cyclopentene–oxygen–argon mixtures were measured behind reflected shock waves. Mixtures contained 0.5% or 1% of hydrocarbons for equivalence ratios ranging from 0.5 to 1.5. Reflected shock wave conditions were as follows: temperatures from 1300 to 1700 K and pressures from 7 to 9 atm. When compared with the previous results obtained under similar conditions, it can be observed that the reactivity of cyclopentene is much lower than that of cyclohexene, but very close to that of cyclopentane. A kinetic mechanism recently proposed for the combustion of cyclopentene in a flame has been used to model these results, and a satisfactory agreement is obtained. The main reaction pathways have been derived from the flow rate, simulated temporal profiles of products, and sensitivity analyses. © 2007 Wiley Periodicals, Inc. Int J Chem Kinet 40: 25–33, 2008
Paradoxical aspects of parkinsonian tremor
Authors: Fishman Paul S.
Published: October 2007

Although resting tremor is the most identifiable sign of Parkinson's disease, its underlying basis appears to be the most complex of the cardinal signs. The variable relationship of resting tremor to other symptoms of PD has implications for diagnosis, prognosis, medical and surgical treatment. Structural lesions very rarely cause classic resting tremor, with likely contributions to tremor by a network of neurons both within and outside the basal ganglia. Patients with only resting tremor show dopaminergic deficits with radioligand imaging, but severity of tremor correlates poorly in such dopamine imaging studies. Correlation of tremor severity to changes in radioligand studies is also limited by the use of mostly qualitative measures of tremor severity. A complex pharmacologic basis of parkinsonian resting tremor is supported by treatment studies. Although levodopa is clearly effective for resting tremor, several agents have shown efficacy that appears to be superior or additive to that of levodopa including anticholinergics, clozapine, pramipexole, and budipine. Although the thalamus has the greatest body of evidence supporting its role as an effective target for surgical treatment of tremor, recent studies suggest that the subthalamic nucleus may be a reasonable alternative target for patients with Parkinson's disease and severe tremor as the predominant symptom. © 2007 Movement Disorder Society
Morphometric changes of gray matter in Parkinson's disease with depression: A voxel‐based morphometry study
Authors: Feldmann Adam , Illes Zsolt , Kosztolanyi Peter , Illes Eniko , Mike Andrea , Kover Ferenc , Balas Istvan , Kovacs Norbert , Nagy Ferenc
Published: October 2007

The origin of the high rate of depression in idiopathic Parkinson's disease (PD) is unknown. We applied voxel‐based morphometry (VBM), as a sensitive tool in detection of gray matter MR density alterations, to find differences in depressed and nondepressed PD patients. Patients with idiopathic PD were classified into depressed (DPD) and nondepressed (NDPD) groups based on the Montgomery‐Åsberg Depression Rating Scale (MADRS). Subsequently, a group comparisons were performed between depressed PD (n = 23), nondepressed PD (n = 27) and normal healthy controls (NC, n = 16). There was no difference in gray matter density comparing healthy controls to any PD groups. However, when NDPD and DPD cohorts were compared, density alteration of the bilateral orbitofrontal, bilateral rectal gyrus, and also the right superior temporal pole was detected in the depressed subgroup. Exploratory analyses revealed an inverse correlation of MADRS scores and severity of VBM alteration in these regions beside the right medial temporal gyrus, anterior and medial cingular gyrus, and parahippocampal gyrus. These results suggest that depression in PD is related to gray matter decrease in the bilateral orbitofrontal and right temporal regions as well as the limbic system. © 2007 Movement Disorder Society
Motion analysis of a child with Niemann–Pick disease type C treated with miglustat
Authors: Paciorkowski Alex R. , Westwell Melany , Õunpuu Sylvia , Bell Katharine , Kagan Jeanne , Mazzarella Cindy , Greenstein Robert M.
Published: October 2007

Niemann–Pick disease type C (NPC) is a progressive neurodegenerative disorder for which there is no effective treatment other than supportive therapy. Recently, the oral medication miglustat has been offered as a possible therapy aimed at reducing pathological substrate accumulation. This article describes the use of computerized three‐dimensional motion analysis to evaluate a 3‐year‐old child with NPC treated with miglustat for 12 months. Motion analysis provided quantitative data on the patient's gait. However, dementia and motor dysfunction progressed despite the treatment, and the patient lost the ability to walk between 9 and 12 months of the study. Motion analysis should be considered among the tools for measuring functional outcomes in future therapeutical trials of patients with neurodegenerative diseases. It is not possible to draw conclusions about miglustat therapy in NPC from a single patient experience. © 2007 Movement Disorder Society
Pallidal deep brain stimulation improves quality of life in segmental and generalized dystonia: Results from a prospective, randomized sham‐controlled trial
Authors: Mueller Joerg , Skogseid Inger M. , Benecke Reiner , Kupsch Andreas , Trottenberg Thomas , Poewe Werner , Schneider Gerd H. , Eisner Wilhelm , Wolters Alexander , Müller J.U. , Deuschl Günther , Pinsker Marcus O. , Roeste Geir K. , Vollmer‐Haase Juliane , Brentrup Angela , Krause Martin , Tronnier Volker , Schnitzler Alfons , Voges Jüergen , Nikkhah Guido , Vesper Jan , Naumann Markus , Volkmann Jens ,   Deep‐Brain Stimulation for Dystonia Study Group
Published: October 2007

As part of the first randomized, sham‐timulation controlled trial on deep brain stimulation (DBS) in primary segmental or generalized dystonia, health‐related quality of life (HRQoL) was assessed by SF‐36. After the 3‐month sham‐controlled phase, significant HRQoL improvement occurred only in the active‐stimulation group. The open‐label extension phase resulted in a significant improvement in all SF‐36 domains following 6 months of neurostimulation. These results demonstrate a favorable impact of DBS on HRQoL in primary dystonia. © 2007 Movement Disorder Society
Talk the walk: The importance of teaching patients how to use their walking stick effectively and safely
Authors: Sheehan Nicholas J. , Millicheap Pat
Published: October 2007

Background: Walking sticks are used widely by people with arthritis, principally to reduce pain and improve stability and balance. However, they are frequently used incorrectly and can be dangerous if not properly maintained.

Methods: Fifty randomly selected patients attending a rheumatology department were surveyed to determine whether their stick was appropriate to their needs and whether they were using it correctly.

Results: Of the 50 patients, 38% used their stick incorrectly, usually in the wrong hand. Forty‐four per cent of sticks were of the wrong length and 54% were in imperfect condition, the main defect being a worn ferrule. Among the minority (18 patients) who had received instruction and training, 72% used their stick correctly, while only 50% of those who had not been trained used their stick in the correct hand where applicable to their condition.

Conclusions: These findings highlight the importance of educating patients on how to obtain greatest benefit from their walking stick and of the necessity to check it regularly for defects to ensure safe usage.
Radial basis collocation method and quasi‐Newton iteration for nonlinear elliptic problems
Authors: Hu H.Y. , Chen J.S.
Published: October 2007

This work presents a radial basis collocation method combined with the quasi‐Newton iteration method for solving semilinear elliptic partial differential equations. The main result in this study is that there exists an exponential convergence rate in the radial basis collocation discretization and a superlinear convergence rate in the quasi‐Newton iteration of the nonlinear partial differential equations. In this work, the numerical error associated with the employed quadrature rule is considered. It is shown that the errors in Sobolev norms for linear elliptic partial differential equations using radial basis collocation method are bounded by the truncation error of the RBF. The combined errors due to radial basis approximation, quadrature rules, and quasi‐Newton and Newton iterations are also presented. This result can be extended to finite element or finite difference method combined with any iteration methods discussed in this work. The numerical example demonstrates a good agreement between numerical results and analytical predictions. The numerical results also show that although the convergence rate of order 1.62 of the quasi‐Newton iteration scheme is slightly slower than rate of order 2 in the Newton iteration scheme, the former is more stable and less sensitive to the initial guess. © 2007 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2008
Multiple genetic and epigenetic biomarkers for lung cancer detection in cytologically negative sputum and a nested case–control study for risk assessment
Authors: Hsu H‐S , Chen T‐P , Wen C‐K , Hung C‐H , Chen C‐Y , Chen J‐T , Wang Y‐C
Published: October 2007

The purpose of this study was to define a biomarker panel for detection of cancer cells in cytologically negative sputum and to evaluate the panel for assessment of lung cancer risk. We examined 19 genetic and epigenetic markers using a sensitive fluorescence‐based method in cytologically negative sputum and in lung tumour tissues from 82 lung cancer patients. We also used these markers to test the sputum of 37 cancer‐free individuals who were matched by age, sex, and smoking habit. Based on the concordance of biomarkers in lung tumours and corresponding sputum, and the low prevalence in cancer‐free individuals, we selected seven markers for a nested case–control study: microsatellite instability of D9S942; loss of heterozygosity of D9S286, D9S942, GATA49D12, and D13S170; and methylation of p16INK4a and RARβ. Based on the assumption that a lung cancer cell has alterations in two or more of the seven biomarkers, we compared the pattern of biomarker alteration in lung tumours and corresponding sputum. Our comparison yielded a sensitivity of 82%, specificity of 75%, and concordance of 79%. Three cancer‐free individuals were considered to have an elevated risk based on the criterion that their sputum showed alteration in two of the seven biomarkers. One individual was indeed diagnosed as having lung cancer 18 months after sputum collection. In the nested case–control study, six biomarkers showed significantly increased odds ratios ranging from 3.14 to 11.24. Our study defines a biomarker panel for detection of cancer cells in cytologically negative sputum and verifies its use for risk assessment of lung cancer. In combination with conventional diagnostic tools, this multiple genetic and epigenetic panel should improve the detection or risk assessment of lung cancer. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Loss of PL6 protein expression in renal clear cell carcinomas and other VHL‐deficient tumours
Authors: Ivanova AV , Vortmeyer A , Ivanov SV , Nickerson ML , Maher ER , Lerman MI
Published: October 2007

Mutations in the von Hippel–Lindau tumour suppressor gene (VHL) cause the VHL hereditary cancer syndrome and occur in most sporadic clear cell renal cell cancers (CC‐RCCs). The mechanisms by which VHL loss of function promotes tumour development in the kidney are not fully elucidated. Here, we analyse expression of PL6, one of the potential tumour suppressor genes from the critical 3p21.3 region involved in multiple common cancers. We classify PL6 as a Golgi‐resident protein based on its perinuclear co‐localization with GPP130 in all cells and tissues analysed. We show that PL6 RNA and protein expression is completely or partially lost in all analysed CC‐RCCs and other VHL‐deficient tumours studied, including the early precancerous lesions in VHL disease. The restoration of VHL function in vitro in the VHL‐deficient CC‐RCC cell lines was found to reinstate PL6 expression, thus establishing a direct link between VHL and PL6. Insensitivity of PL6 to hypoxia suggested that PL6 is regulated by VHL via a HIF‐1‐independent pathway. We ruled out mutations and promoter methylation as possible causes of PL6 down‐regulation in CC‐RCC. We hypothesize that loss of a putative PL6 secretory function due to VHL deficiency is an early and important event that may promote tumour initiation and growth. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
The basal‐like breast carcinoma phenotype is regulated by SLUG gene expression
Authors: Storci G , Sansone P , Trere D , Tavolari S , Taffurelli M , Ceccarelli C , Guarnieri T , Paterini P , Pariali M , Montanaro L , Santini D , Chieco P , Bonafé M
Published: October 2007

Basal‐like breast carcinoma is an aggressive form of breast cancer, characterized by the absence of oestrogen receptor and HER2 expression, the presence of cytokeratin 5 and epidermal growth factor receptor expression, and by the up‐regulation of stem cell regulatory genes. We show here that tumour tissues expressing high levels of SLUG mRNA show a basal‐like breast carcinoma phenotype and that such tumours also express high levels of stem cell‐regulatory genes, ie CD133, Bmi1. Further, we show that stem/progenitor cells, isolated from ductal breast carcinoma and from normal mammary gland as mammospheres, express SLUG, CD133, and Bmi1 mRNA and show a phenotype similar to that of basal‐like breast carcinoma. We also report that SLUG expression in tumour tissues correlates with that of the hypoxia survival gene carbonic anhydrase IX. In this regard, we report that the exposure of SLUG‐negative/luminal‐like MCF‐7 cells to a hypoxic environment promotes the onset of the basal‐like breast carcinoma phenotype, together with up‐regulation of the SLUG gene, which in turn blunts oestrogen receptor‐α and boosts carbonic anhydrase IX gene expression. Finally, we show that SLUG expression promotes the invasiveness of MCF‐7 cells exposed to hypoxia and sustains the in vivo aggressiveness of hypoxia‐selected, MCF‐7‐derived cells in xenografts. These data indicate that SLUG gene expression is part of a hypoxia‐induced genetic programme which sets up a basal/stem cell‐like, aggressive phenotype in breast cancer cells. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.