bluuebunny/crossref_metadata_2025_split huggingface dataset:
Optimization of transglutaminase extraction produced by Bacillus circulans BL32 on solid‐state cultivation
Authors: de Souza Claucia Fernanda Volken , Rodrigues Rafael Costa , Heck Júlio Xandro , Ayub Marco Antônio Záchia 
Published: April 2008

AbstractBACKGROUND: This paper reports investigations of the extraction of transglutaminase (TGase) produced by Bacillus circulans BL32 on solid‐state cultivation in order to obtain a crude extract with the highest possible specific activity. The optimization of downstream processing parameters for the effective recovery of the enzyme was carried out using response surface methodology based on the central composite rotatable design (CCRD) to reduce losses in the cultivated solids and to obtain a crude extract as concentrated as possible. Several solvents and temperatures were tested, followed by a 23 factorial design performed to optimize conditions extraction time, mechanical agitation, and solid:liquid ratio.RESULTS: The mathematical model showed that solid:liquid ratio has a significant negative effect on transglutaminase recovery. The optimal conditions for extraction were: water as solvent at 7 °C; 5 min extraction time; agitation speed 250 rpm; and 1:6 solid:liquid ratio. Under these conditions the model predicts a maximum response of 0.291 U mg−1 of protein of transglutaminase activity recovery, very closely matching experimental activity of 0.285 U mg−1 of protein. TGase recovery achieved under the optimized extraction conditions, according to the CCRD, was 2.5‐fold higher than that obtained under non‐optimized conditions previously employed.CONCLUSION: Results show that TGase can be produced in cheap solid state cultivations and the optimization of its downstream processing parameters can improve enzyme recovery in crude extracts and may have important impacts on enzyme costs. Copyright © 2008 Society of Chemical Industry
High resolution X‐ray phase contrast synchrotron imaging of normal and ligation damaged rat sciatic nerves
Authors: Kim Bong‐Il , Kim Ki‐Hong , Youn Hwa‐Shik , Jheon Sanghoon , Kim Jong‐Ki , Kim Hongtae 
Published: April 2008

AbstractThis study was performed to apply synchrotron radiation (SR) imaging to a neuropathologic evaluation technique after treatment of peripheral nerve blocks. A phase contrast synchrotron images of normal and ligation damaged rat sciatic nerve were obtained with an 8 KeV monochromatic beam and 20‐μm thick CsI(TI) scintillation crystal. The visual image was magnified using a 20× microscope objective and captured using an analog CCD camera. Obtained images were compared with conventional light microscopic findings from the same nerve samples. By using an edge enhancement effect of phase const with SR, we could easily discriminate each nerve fiber and identify the arrangement of nerve fibers within a whole thickness (about 1 mm in diameter) of peripheral nerve without sectioning and fixation. The composite SR image of a ligation damaged rat sciatic nerve sample showed that the response to nerve injury was different on each side of the site of injury. The SR image of damaged distal lesion showed destruction of neural microarchitecture and typical extensive Wallerian degeneration of nerve fibers as clearly as histologic image. We could get very detailed morphologic data for Wallerian degeneration of nerve fibers by using the SR imaging technique. We believe that the phase contrast synchrotron imaging has great potential as an imaging tool in the bioscience and medical science. Microsc. Res. Tech., 2008. © 2008 Wiley‐Liss, Inc.
Enrichment of eicosapentaenoic acid and docosahexaenoic acid from sardine by‐products by supercritical fluid fractionation
Authors: Létisse Marion , Comeau Louis 
Published: April 2008

AbstractBased on the principle of supercritical chromatography, a fractionation process for fatty acid methyl esters (FAMEs) under supercritical conditions was studied with the aim of obtaining in extracts highly enriched eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) from fish cannery waste. Yields of the fractionation process were enhanced by using adjuvant material and modifying CO2volumetric density and temperature. The combination of adjuvant properties with optimized pressure and temperature conditions permitted efficient fractionations of FAMEs, according to chain length and degree of unsaturation, in high purity (up to 95% of FAME) and good yields (45% of EPA and DHA starting potential). This work shows how green technologies, such as supercritical processes, can constitute a good alternative to the use of organic solvents in classical methods for valorisation of complex food industry waste.
Supercritical fluid extraction of polyhalogenated pollutants from aquaculture and marine environmental samples: A review
Authors: García‐Rodríguez Diego , Carro‐Díaz Antonia María , Lorenzo‐Ferreira Rosa Antonia 
Published: April 2008

AbstractThis article focuses on the state‐of‐the‐art in sample preparation using supercritical fluid extraction (SFE), to monitor the content of polyhalogenated pollutants in aquaculture and marine environmental samples. Marine sediments and biological applications, including several types of samples matrices (fish, shellfish, seaweed and fish feed) and analyte groups (polychlorinated biphenyls (PCBs), polybrominated biphenyls (PBBs), polybrominated diphenylethers (PBDEs), polychlorinated dibenzo‐p‐dioxin (PCDD)/Fs and organochlorinated pesticide (OCPs)) are discussed with respect to SFE use and optimisation of conditions. We also discuss the great analytical potential of SFE, the integration of the extraction and clean‐up steps for rapid sample processing justifying its use for routine work. The most recent SFE applications to the determination of these pollutants in marine environmental (biota and sediment) samples, published in the last 15 years, are reviewed.
Overview of the retention in subcritical fluid chromatography with varied polarity stationary phases
Authors: Lesellier Eric 
Published: April 2008

AbstractRetention and separation of achiral compounds in supercritical fluid chromatography (SFC) depend on numerous parameters: some of these parameters are identical to those encountered in HPLC, such as the mobile phase polarity, while others are specific to SFC, as the density changes of the fluid, due to temperature and/or pressure variations. Additional effects are also related to the fluid compressibility, leading to unusual retention changes in SFC, for instance when flow rate or column length is varied. These additional effects can be minimised by working at lower temperatures in the subcritical domain, simplifying the understanding of retention behaviours. In these subcritical conditions, varied modifiers can be mixed to carbon dioxide, from hexane to methanol, allowing tuning the mobile phase polarity. With nonpolar modifiers, polar stationary phases are classically used. These chromatographic conditions are close to the ones of normal‐phase LC. The addition of polar modifiers such as methanol or ACN increases the mobile phase polarity, allowing working with less polar stationary phases. In this case, despite the absence of water, retention behaviours generally follow the rules of RP LC. Moreover, because identical mobile phases can be used with all stationary phase types, from polar silica to nonpolar C18‐bonded silica, the classical domains, RP and normal‐phase, are easily brought together in SFC. A unified classification method based on the solvation parameter model is proposed to compare the stationary phase properties used with the same subcritical mobile phase.
Nonexistence of local minima of supersolutions for the polyharmonic problems
Authors: Li Liangpan 
Published: April 2008

AbstractIn this note we study the nonexistence of local minima of the supersolutions of the polyharmonic equations on the balls under generalized homogeneous Dirichlet boundary conditions. Under suitable restriction on the dimensions, this means that a generalized clamped circular plate, which is pushed from below, cannot bend downwards even locally. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Positive solutions of non‐positone Dirichlet boundary value problems with singularities in the phase variables
Authors: Agarwal Ravi P. , O'Regan Donal , Staněk Svatoslav 
Published: April 2008

AbstractThe paper presents existence results for positive solutions of the differential equations x ″ + μh (x) = 0 and x ″ + μf (t, x) = 0 satisfying the Dirichlet boundary conditions. Here μ is a positive parameter and h and f are singular functions of non‐positone type. Examples are given to illustrate the main results. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Unique like everybody else? The dual role of consumers' need for uniqueness
Authors: Ruvio Ayalla 
Published: April 2008

AbstractUniqueness has a positive and attractive connotation, but being too unique can result in social sanctions. This paper focuses on the dual role of consumers' need for uniqueness. The findings of two studies in Israel support the notion that expressing uniqueness via consumption behavior is a safe way to achieve a different sense of being without damaging an individual's sense of social assimilation. The results imply a possible new theoretical view of the interplay between consumers' need for uniqueness and their need for social assimilation. © 2008 Wiley Periodicals, Inc.
An empirical investigation of framing effects in negotiations: A study of single‐family home sales
Authors: Witte Carl L. , Grünhagen Marko , Gentry James W. 
Published: April 2008

AbstractThis paper integrates Prospect Theory and the concept of framing in a study of consumer negotiated pricing in a real estate context. Building on previously conducted experimental designs, a field survey indicated that home sellers using sales price as a reference point display greater willingness to make concessions than those who use equity as their reference point. Further, the third‐party influence of the realtor was shown to alter Prospect Theory predictions so that even equity‐based sellers became concessionary. © 2008 Wiley Periodicals, Inc.
Test–retest repeatability of assessing environmental and lifestyle factors in Parkinson's disease
Authors: Yip Chun‐Wai , Tan Eng‐King 
Published: April 2008

AbstractEpidemiological studies of environmental risk factors in Parkinson's disease (PD) are dependent on recollection of past exposures based on patients' self‐reports. There are limited studies that have assessed the quality of such data. We conducted a prospective study to determine the test–retest repeatability of environmental and lifestyle factors, and medical data in a PD cohort of Asian ethnicity. A total of 150 consecutive PD patients were initially screened, and 100 were recruited and completed an initial interview. Eighty‐three patients completed the second interview more than 6 months later. Lifestyle habits (such as smoking and coffee consumption) showed excellent agreement (κ > 0.90). For the amount and duration of coffee, tea, alcohol, and cigarette smoking exposure, the total agreement in the response for these factors in the repeat interview were noted in 71.4%, 73.3%, 100%, and 90%, respectively (ICC > 0.83). Medical conditions for which the patients were on treatment, such as diabetes, hypertension, and stroke, revealed very high repeatability (κ = 0.81–0.90). Environmental exposures like well‐water consumption and prior farm‐dwelling produced a moderately good repeatability (κ = 0.66–0.77). In conclusion, our study demonstrates that even over long interval period of more than half a year, self‐report lifestyle exposure information, personal and environmental exposure data can be collected with moderate‐to‐high repeatability from PD patients. © 2008 Movement Disorder Society
Apathy following subthalamic stimulation in Parkinson disease: A dopamine responsive symptom
Authors: Czernecki Virginie , Schüpbach Michael , Yaici Sadek , Lévy Richard , Bardinet Eric , Yelnik Jérôme , Dubois Bruno , Agid Yves 
Published: April 2008

AbstractTo evaluate the effects of the dopamine D2‐D3 agonist ropinirole in patients who developed apathy after complete withdrawal from dopaminergic medication following successful subthalamic nucleus (STN) stimulation for advanced Parkinson disease (PD). We assessed apathy (Apathy Scale, Apathy Inventory), mood (Montgomery‐Åsberg Depression Rating Scale), cognitive functions (Mattis Dementia rating scale, frontal score, executive tests) and motor state (UPDRS‐III) in 8 PD patients treated with STN stimulation without dopaminergic treatment and who became apathetic. Assessments were made at baseline and after 6 weeks of ropinirole treatment (7.2 ± 5.9 mg/d; range 1–18 mg/d). Apathy improved with ropinirole in all but 1 patient (54 ± 24%; range 0–78%). Mood also improved (75 ± 31%; range 0–100%), but not in correlation with the change in apathy. Cognitive performance was not modified. Stimulation contacts were located within the STN in all patients except the one who remained apathetic in spite of ropinirole treatment (zona incerta). We suggest that apathy, which was compensated for by an enhancement of D2‐D3 receptor stimulation in PD patients with STN stimulation: (1) depends on a dopaminergic deficit in associativo‐limbic areas of the brain and (2) can be avoided if a dopaminergic agonist is administered postoperatively. © 2008 Movement Disorder Society
Effect of curcumin supplementation on blood glucose, plasma insulin, and glucose homeostasis related enzyme activities in diabetic db/db mice
Authors: Seo Kwon‐Il , Choi Myung‐Sook , Jung Un Ju , Kim Hye‐Jin , Yeo Jiyoung , Jeon Seon‐Min , Lee Mi‐Kyung 
Published: April 2008

AbstractWe investigated the effect of curcumin on insulin resistance and glucose homeostasis in male C57BL/KsJ‐db/db mice and their age‐matched lean non‐diabetic db/+ mice. Both db/+ and db/db mice were fed with or without curcumin (0.02%, wt/wt) for 6 wks. Curcumin significantly lowered blood glucose and HbA1c levels, and it suppressed body weight loss in db/db mice. Curcumin improved homeostasis model assessment of insulin resistance and glucose tolerance, and elevated the plasma insulin level in db/db mice. Hepatic glucokinase activity was significantly higher in the curcumin‐supplemented db/db group than in the db/db group, whereas glucose‐6‐phosphatase and phosphoenolpyruvate carboxykinase activities were significantly lower. In db/db mice, curcumin significantly lowered the hepatic activities of fatty acid synthase, β‐oxidation, 3‐hydroxy‐3‐methylglutaryl coenzyme reductase, and acyl‐CoA: cholesterol acyltransferase. Curcumin significantly lowered plasma free fatty acid, cholesterol, and triglyceride concentrations and increased the hepatic glycogen and skeletal muscle lipoprotein lipase in db/db mice. Curcumin normalized erythrocyte and hepatic antioxidant enzyme activities (superoxide dismutase, catalase, gluthathione peroxidase) in db/db mice that resulted in a significant reduction in lipid peroxidation. However, curcumin showed no effect on the blood glucose, plasma insulin, and glucose regulating enzyme activities in db/+ mice. These results suggest that curcumin seemed to be a potential glucose‐lowering agent and antioxidant in type 2 diabetic db/db mice, but had no affect in non‐diabetic db/+ mice.
Immunomodulatory effects of curcumin in allergy
Authors: Kurup Viswanath P. , Barrios Christy S. 
Published: April 2008

AbstractRecent years have witnessed a global increase in allergy and asthma, particularly in developed countries. Attempts to develop effective control measures for allergy and asthma resulted in the exploration of alternate medicines including herbal remedies traditionally used in old world countries. Turmeric is known for its multiple health restoring properties, and has been used in treating several diseases including several respiratory disorders. Turmeric is a common spice used in the culinary preparations in South and East Asian countries. The active component of turmeric is curcumin, a polyphenolic phytochemical, with anti‐inflammatory, antiamyloid, antiseptic, antitumor, and antioxidative properties. Curcumin was reported to have antiallergic properties with inhibitory effect on histamine release from mast cells. The effectiveness of curcumin in allergy and asthma has been further investigated using a murine model of allergy. The results indicate a marked inhibition of allergic response in animals treated with curcumin suggesting a major role for curcumin in reducing the allergic response. The present review focuses on the results of research aimed to understand the immunomodulation induced by curcumin and its associated roles in the amelioration of allergy. These findings needed further evaluation, extrapolation, and confirmation before using curcumin for controlling allergy and asthma in humans.
Resveratrol inhibits migration and invasion of human breast‐cancer cells
Authors: Tang Feng‐Yao , Su Yu‐Ching , Chen Nai‐Chia , Hsieh Hui‐Shan , Chen Kaun‐Suei 
Published: April 2008

AbstractMetastasis is the primary cause of death from breast cancer. Cell migration and invasion play important roles in neoplastic metastasis. The insulin‐like growth factor (IGF‐1) stimulates cell migration through activation of PI‐3K/Akt signaling pathway. IGF‐1 induces the tumorigenicity of many types of cancer cells and is critical for metastatic cell spread in estrogen receptor (ER)‐negative breast‐cancer cells. Matrix metalloproteinase‐2 (MMP‐2) is a key enzyme in the degradation of extracellular matrices and its expression has been dysregulated in breast cancer invasion and metastasis. Resveratrol exhibited potential anticarcinogenic activities in several studies. However, the inhibitory effects of resveratrol on the expression of MMP‐2, migration and invasion of breast‐cancer cell have not been demonstrated yet. In the present study, we investigated the anti‐invasive mechanism of resveratrol in human breast cancer MDA‐MB 435cells. Here, we showed that IGF‐1 is a potent stimulant of the migration of ER‐negative human breast‐cancer cells. Resveratrol could inhibit IGF‐1‐mediated cell migration of MDA‐MB 435 in vitro. The inhibitory effect of resveratrol was mediated in part through the suppression of the activation of PI‐3K/Akt signaling pathway. Furthermore, IGF‐1‐mediated expression of MMP‐2 was significantly inhibited by resveratrol in concomitance with alteration of cell invasion.
Structure elucidation of five new iridoid glucosides from the leaves of Avicennia marina
Authors: Sun Yu , Ouyang Jie , Deng Zhiwei , Li Qingshan , Lin Wenhan 
Published: April 2008

AbstractA chemical examination of the mangrove plant Avicennia marina (Forrsk.) Vierh resulted in the isolation and characterization of five new iridoids, marinoids A–E (1–5), along with 2′‐cinnamoyl‐mussaenosidic acid (6), 2′‐O‐(4″‐methoxycinnamoyl) mussaenosidic acid (7), 2′‐O‐(4″‐hydroxycinnamoyl) mussaenosidic acid (8), and 3(R)‐hydroxy‐5‐phenyl‐4(E)‐pentenoic acid (9). The structures of 1–5 were elucidated on the basis of 1D and 2D NMR (COSY, HMQC, HMBC, and NOESY) in association with IR and MS data analysis. Copyright © 2008 John Wiley & Sons, Ltd.
Genomic origin, processing and developmental expression of testicular outer dense fiber 2 (ODF2) transcripts and a novel nucleolar localization of ODF2 protein
Authors: Rivkin Eugene , Tres Laura L. , Kierszenbaum Abraham L. 
Published: April 2008

AbstractOuter dense fibers are a major constituent of the sperm tail and outer dense fiber 2 (ODF2) protein is one of their major components. ODF2 shares partial homology with cenexin 1 and cenexin 2, regarded as centriolar proteins. We show that ODF2 and cenexin 2 transcripts are the product of differential splicing of a single gene, designated Cenexin/ODF2 and that cenexin 1 is an incomplete clone of ODF2. ODF2 terminates in exon 20b whereas in cenexin 2 this exon is spliced out and translation terminates in exon 24. We demonstrate a transcriptional switch during rat testicular development, from somatic‐type to testis‐type ODF2 and cenexin transcripts during the onset of meiosis. The switch is completed when spermiogenesis is established. ODF2 immunoreactive sites were visualized in the acroplaxome, along the sperm tail and the centrosome‐derived sperm head‐to‐tail coupling apparatus. An unexpected finding was the presence of ODF2 antigenic sites, but not cenexin antigenic sites, in the dense fibrillar component of the nucleolus of Sertoli cells, spermatogonia and primary spermatocytes. The characterization of the genomic origin, processing and developmental expression of ODF2 transcript isoforms and their protein products can help reconcile differences in the literature on the role of ODF2 and cenexin in the centrosome. Furthermore, the finding of ODF2 in the dense fibrillar component of the nucleolus suggests that this protein, in addition to its presence in sperm outer dense fibers and centrosome, highlights and adds to the nucleolar function during spermatogenesis and early embryogenesis. Mol. Reprod. Dev. 75: 1591–1606, 2008. © 2008 Wiley‐Liss, Inc.
High order implicit collocation method for the solution of two‐dimensional linear hyperbolic equation
Authors: Dehghan Mehdi , Mohebbi Akbar 
Published: April 2008

AbstractIn this article, we introduce a high‐order accurate method for solving the two dimensional linear hyperbolic equation. We apply a compact finite difference approximation of fourth order for discretizing spatial derivatives of linear hyperbolic equation and collocation method for the time component. The resulted method is unconditionally stable and solves the two‐dimensional linear hyperbolic equation with high accuracy. In this technique, the solution is approximated by a polynomial at each grid point that its coefficients are determined by solving a linear system of equations. Numerical results show that the compact finite difference approximation of fourth order and collocation method give a very efficient approach for solving the two dimensional linear hyperbolic equation. © 2008 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2009
A characteristic finite element method with local mesh refinements for the Lamm equation in analytical ultracentrifugation
Authors: Liu Jiangguo , Chen Chaoping 
Published: April 2008

AbstractThe Lamm equation is a fundamental differential equation in analytical ultracentrifugation, for describing the transport of solutes in an ultracentrifuge cell. In this article, we present a characteristic finite element method with local mesh refinements for solving the Lamm equation. The numerical method is mass‐conservative by design and allows relatively large time steps to be used. Numerical experiments indicate that the numerical solutions are oscillation‐free in the region near the cell bottom, where mass build up and large concentration gradients occur. Positivity of solutions is also well kept. © 2008 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2009