bluuebunny/crossref_metadata_2025_split huggingface dataset:
Regulation of protein kinases and coregulatory interplay of S‐100β and serotonin transporter on serotonin levels in diabetic rat brain
Authors: Ramakrishnan R. , Sheeladevi R. , Namasivayam A. 
Published: August 2008

AbstractProtein kinases are critical component in the regulation of signal transduction pathways, including neurotransmitters. Our previous studies have shown that serotonin (5‐HT) altered under diabetic condition was accompanied by alterations of protein kinase C‐α (PKC‐α) and CaMKII, and those alterations were reversed after insulin administration. The current study showed that alloxan‐induced diabetic animals revealed hyperglycemia and was associated with an increase in the content of 5‐HT, PKC‐α expression and PKC activity (P< 0.05) simultaneously in striatum (ST), midbrain (MB), pons medulla (PM), cerebellum (CB), and cerebral cortex (CCX) from 7 days to 60 days. Although the 5‐HT levels in hippocampus (HC) and hypothalamus (HT) were not altered, the PKC‐α expression and PKC activity showed increases (P< 0.05) in level in HC. Insulin administration reversed all these changes to a normal level. In contrast, the in vitro study has shown that the 5‐HT levels correlated with PKC‐α expressions as well as PKC activity (P< 0.05) only in ST, MB, and CB either after induction with phorbol 12‐myristate 13‐acetate (PMA) or blocking with chelerythrine, whereas PM and CCX remained elevated (P< 0.05), implying a regulatory role for PKC‐α only in ST, MB, and CB. However, our consecutive studies have shown that the 5‐HT level in PM was regulated by p38‐mitogen‐activated protein kinase (p38‐MAPK) both in vivo and in vitro, whereas the 5‐HT level in CCX was coregulated by S‐100β by protein–protein interaction with serotonin transporter (SERT) via 8‐bromoadenosine 3′,5′‐cyclic monophosphate sodium salt (8‐Br‐cAMP)‐induced cAMP/PKAII pathway(s). © 2008 Wiley‐Liss, Inc.
1H‐[1,2,4]oxadiazolo[4,3‐a]quinoxalin‐1‐one inhibits neurite outgrowth and causes neurite retraction in PC12 cells independently of soluble guanylyl cyclase
Authors: Lee Han Gil , Kim So Young , Kim Du Sik , Seo Su Ryeon , Lee Syng‐Ill , Shin Dong Min , De Smet Patrick , Seo Jeong Taeg 
Published: August 2008

AbstractThe effect of the potent soluble guanylyl cyclase (sGC) inhibitor 1H‐[1,2,4]oxadiazolo[4,3‐a]quinoxalin‐1‐one (ODQ) on neurite outgrowth and retraction was investigated in PC12 cells and SH‐SY5Y human neuroblastoma cells. ODQ inhibited neurite outgrowth and triggered neurite retraction in the cells stimulated with nerve growth factor (NGF), staurosporine, or Y‐27632. The nitric oxide (NO) scavenger 2‐(4‐carboxyphenyl)‐4,4,5,5‐tetramethyl‐imidazoline‐1‐oxyl‐3‐oxide (PTIO) had little effect on neurite outgrowth induced by Y‐27632 or staurosporine. In the presence of ODQ, treatment of the cells with the cell‐permeable cGMP analogue 8‐bromo‐cGMP failed to retrigger Y‐27632‐ and staurosporine‐induced neurite outgrowth. Furthermore, the depletion of sGC by RNA interference failed to prevent Y‐27632‐ and staurosporine‐induced neurite outgrowth. These results indicate that the NO/sGC/cGMP signaling cascade is not critically involved in ODQ‐induced neurite remodeling. The MEK inhibitor PD98059 did not inhibit neurite outgrowth, and Y‐27632 and staurosporine did not induce ERK phosphorylation, suggesting that the inhibitory effect of ODQ on neurite outgrowth is independent of the ERK signaling pathway. In contrast, pretreatment with dithionite or a hemin‐glutathione mixture reversed the inhibitory effect of ODQ on Y‐27632‐ and staurosporine‐induced neurite outgrowth, indicating that ODQ might act on an intracellular redox‐sensitive molecule. We conclude that ODQ inhibits Y‐27632‐ and staurosporine‐induced neurite outgrowth and triggers neurite retraction in an sGC‐independent manner in neuronal cells and suggest that oxidation of unidentified redox‐sensitive protein could be responsible for these effects. © 2008 Wiley‐Liss, Inc.
Validation of reference genes for normalization of real‐time quantitative RT‐PCR data in traumatic brain injury
Authors: Cook Naomi L. , Vink Robert , Donkin James J. , van den Heuvel Corinna 
Published: August 2008

AbstractCareful validation of reference genes used for the normalization of real‐time RT‐PCR data is required to obtain accurate results regarding gene expression. We evaluated the stability of seven commonly used reference genes in the cerebral cortex and hippocampus of rats 3 days following traumatic brain injury (TBI). HPRT, SDHA, and GUSB were found to be the most stable reference genes in the cerebral cortex, whereas B2MG, TBP, and GAPDH were the most stable in the hippocampus. The use of three reference genes was determined to be the optimal number for accurate normalization of data. To illustrate this point, when our gene of interest, substance P (SP), was normalized against the three most stable reference genes in both brain areas, we found no significant difference between injured and uninjured rats at the 3‐day time point. However, when our SP data were normalized to each reference gene individually, SP mRNA level was highly variable depending on the reference gene chosen. The results of the present study highlight the importance of validating reference genes to be used for real‐time RT‐PCR analysis. The use of the most stable reference genes presented here will allow more accurate normalization of gene expression data in TBI. © 2008 Wiley‐Liss, Inc.
Effect of fencing, artificial seeding and abandonment on vegetation composition and dynamics of ‘black soil land’ in the headwaters of the Yangtze and the Yellow Rivers of the Qinghai‐Tibetan Plateau
Authors: Shang Z. H. , Ma Y. S. , Long R. J. , Ding L. M. 
Published: August 2008

AbstractRangeland management can affect plant diversity and plant functional groups of native grassland communities. To improve pasture for livestock grazing from the existing poisonous and ruderal vegetation in the ‘black soil land’ grassland in the headwaters of the Yangtze and the Yellow Rivers (HAYYR) of the Qinghai‐Tibetan Plateau, three treatments (fencing‐FT, artificial seeding with local grasses‐ST and abandonment‐AT) were applied during a 5‐year period (2000–2005). Plant diversity and groups (sedges, grasses and dwarf shrubs) in the treated plots were compared with non‐treated control plots. Results showed that (1) FT promoted an increase in forbs species, but there was no change in the other plant functional groups; (2) with ST, species richness of forbs decreased but grass species increased indicating that sowing local grasses could change plant composition of black soil land in the short‐term, and increase the proportion of grasses and, thus, forage for grazing and (3) AT, after plowing, was similar to CK plots, with forbs being the dominant plant functional group for the 5 years. In conclusion, the goal to alter black soil land cover from poisonous and ruderal plants to more useful plants for livestock grazing by either fencing, artificial seeding or abandonment was not successful in the long term. Copyright © 2008 John Wiley & Sons, Ltd.
A Capelli type theorem for multiplicative convolutions of polynomials
Authors: Bonciocat Anca Iuliana , Ciprian Bonciocat Nicolae 
Published: August 2008

AbstractWe prove a Capelli type theorem on the canonical decomposition for multiplicative convolutions of polynomials. We derive then some irreducibility criteria for convolutions of polynomials in several variables over a given field. The irreducibility conditions are expressed only in terms of the degrees of the polynomials in convolution, the degrees of their coefficients, and the degrees of some suitable divisors of the resulting leading coefficient. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Property (quasi‐α) and the denseness of norm attaining mappings
Authors: Choi Yun Sung , Song Hyun Gwi 
Published: August 2008

AbstractWe introduce property (quasi ‐α), which implies property (A) defined by Lindenstrauss [10] and whose dual property is property (quasi‐β) [2]. We consider relations between this property and other sufficient conditions for property (A), and study the denseness of norm attaining mappings under the conditions of these properties. In particular, if each of the Banach spaces Xk , 1 ≤ k ≤ n – 1, has property (quasi‐α) and Xn has property (A), then the projective tensor product X1 ··· Xn has property (A). (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Stability criterion for second order linear impulsive differential equations with periodic coefficients
Authors: Guseinov G. Sh. , Zafer A. 
Published: August 2008

AbstractIn this paper we obtain instability and stability criteria for second order linear impulsive differential equations with periodic coefficients. Further, a Lyapunov type inequality is also established. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A distributional limit law for the continued fraction digit sum
Authors: Kesseböhmer Marc , Slassi Mehdi 
Published: August 2008

AbstractWe consider the continued fraction digits as random variables measured with respect to Lebesgue measure. The logarithmically scaled and normalised fluctuation process of the digit sums converges strongly distributional to a random variable uniformly distributed on the unit interval. For this process normalised linearly we determine a large deviation asymptotic. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On Hill's operator with a matrix potential
Authors: Veliev O. A. 
Published: August 2008

AbstractIn this article we obtain asymptotic formulas for eigenvalues and eigenfunctions of the self‐adjoint operator generated by a system of Sturm–Liouville equations with summable coefficients and quasiperiodic boundary conditions. Then using these asymptotic formulas, we find conditions on the potential for which the number of gaps in the spectrum of the Hill's operator with matrix potential is finite. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Biosynthesis of Multi‐Component Polyhydroxyalkanoates by the Bacterium Wautersia eutropha
Authors: Volova Tatiana G. , Kalacheva Galina S. , Steinbüchel Alexander 
Published: August 2008

AbstractThe study addresses the effect of different conditions of carbon nutrition on synthesis of polyhydroxyalkanoates by the bacterium Wautersia eutropha. In experiments with two wild type strains (H16 and B5786), it has been first found that under mixotrophic growth conditions – CO2 + co‐substrate (alkanoic acids) – bacteria can synthesize multi‐component PHAs, consisting of short‐ and medium‐chain‐length monomers with carbon chains containing 4 to 8 atoms. It has been shown that PHA composition is determined by the type of the co‐substrate. Fatty acids with odd number of carbons induce bacteria to synthesize four‐ and five‐component PHAs with hydroxybutyrate, hydroxyvalerate as major monomers and hydroxyhexanoate, hydroxyheptanoate and hydroxyoctanoate as minor, occasionally occurring, ones. Fatty acids with even number of carbons induce synthesis of not only their respective monomers (hydroxyhexanoate and hydroxyoctanoate) but also hydroxyvalerate, making possible synthesis of four‐component PHAs, containing hydroxybutyrate and hydroxyhexanoate as major components (up to 18 mol%). A family of short‐ and medium‐chain‐length four‐ and five‐component PHAs were synthesized and their physicochemical properties examined.
Isolation of PHA–Producing Bacteria from Date Syrup Waste
Authors: Ataei Seyed Ahmad , Vasheghani‐Farahani Ebrahim , Shojaosadati Seyed Abbas , Tehrani Hossein Abdul 
Published: August 2008

AbstractSince the major problem associated with the industrial production of Polyhydroxyalkanoates (PHAs) is their high production cost, this study was carried out using date syrup as the major carbon source to decrease the production cost and also help to supply other nutrient requirements. To isolate PHA–producing bacteria for this purpose, microorganisms were isolated from the syrup waste of a local date factory. These purified colonies were screened for intracellular granules by staining with Sudan Black. The positive‐staining strains were grown for production of PHAs in 5% date syrup as carbon source supplemented with mineral salt medium. The culture was incubated at 30 °C with shaking at 140 rpm for 60 h. Among positively stained bacteria, the best PHA producers were selected on the basis of cell growth, cell dry weight, PHA content and the monomer composition of PHA. One of them could utilize date syrup for growth and produce the homopolymer of Polyhydroxybutyrate (PHB) with a cell density of about 5.1 g/L and maximum concentration of PHB equal to 3.6 g/L which is 71% of cell dry weight. Another one produces copolymer of Poly (hydroxybutyrate‐hydroxyvalerate) in date syrup media with a maximum concentration of 2.2 g/L containing 10 wt % valerate in shake flask cultivation.
Luminous Bacteria as Producers of Polyhydroxyalkanoates
Authors: Boyandin Anatoly , Kalacheva Galina S. , Medvedeva Svetlana , Rodicheva Emma , Volova Tatiana G. 
Published: August 2008

AbstractThe study addresses the ability of luminous bacteria of different taxa (Photobacterium leiognathi, Photobacterium phosphoreum, Vibrio harveyi, Vibrio fischeri) to synthesize polyesters of hydrocarbon acids (polyhydroxyalkanoates, PHAs) as storage macromolecules. The screened strains widely varied in their PHA productivity. Conditions for attaining high polymer yields (including two‐ and three‐component polymers) in batch culture have been determined. The attained polymer yields reached 40‐70% of dry cell biomass. The results suggest a conclusion that luminous microorganisms can be considered as producers of multi‐component PHAs.
Brush Type Copolymers of Poly(3‐hydroxybutyrate) and Poly(3‐hydroxyoctanoate) with Same Vinyl Monomers via “Grafting From” Technique by Using Atom Transfer Radical Polymerization Method
Authors: Arslan Hülya , Yeşilyurt Nazlı , Hazer Baki 
Published: August 2008

AbstractBrush type graft copolymers of poly(3‐hydroxybutyrate) (PHB) and poly(3‐hydroxyoctanoate) (PHO) with methylmethacrylate, (MMA), styrene, (S), and n‐butylmethacrylate, (n‐BuMA) were obtained by using Atom Transfer Radical Polymerization Method, (ATRP), via “grafting from” technique. Firstly PHB and PHO were chlorinated by passing chlorine gas through their solution in CHCl3/CCl4 (75/25 v/v) mixture and CCl4, respectively, in order to prepare chlorinated PHB, PHB‐Cl, and chlorinated PHO, PHO‐Cl, with different chlorine contents. The determination of the chlorine content in chlorinated poly(3‐hydroxyalkanoate) (PHA‐Cl) was performed by the Volhard Method. Then ATRP of vinyl monomers was initiated by using PHA‐Cl as macroinitiators in the presence of cuprous chloride (CuCl)/2,2′‐bipyridine complex as catalyst, at 90 °C in order to obtain brushes containing PHAs. The polymer brushes were fractionated by fractional precipitation methods and the γ values calculated from the ratio of the volume of nonsolvent (methanol) and the volume of solvent (chloroform) of brushes varied between 0.82 and 6.50 depending on the composition of brushes. The polymer products were characterized by gel permeation chromatography (GPC), 1H NMR, FTIR, thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) techniques.
Comparative Study of PHA Degradation in Natural Reservoirs Having Various Types of Ecosystems
Authors: Voinova Olga , Gladyshev Michail , Volova Tatiana G. 
Published: August 2008

AbstractThe kinetics of polyhydroxyalkanoate (PHA) degradation in natural environment in two water reservoirs having various ecological characteristics was studied. It was shown that biodegradation of polymer essentially depends on the environment temperature and inorganic composition of water. The processes of polymer degradation under aerobic and anaerobic conditions were compared. The polymer degradation was slower under anaerobic conditions.
Influence of Enzymatic Degradation on Physical Properties of Poly(ε‐caprolactone) Films and Sponges
Authors: Vidaurre Ana , Dueñas José M. Meseguer , Estellés Jorge Más , Cortázar Isabel Castilla 
Published: August 2008

AbstractThe effect of enzymatic degradation on poly(ε‐caprolactone) (PCL) films and sponges was investigated at 37 °C using Pseudomonas lipase. Film samples were prepared by the solution casting method, while sponges were obtained by the freeze extraction method. The porosity was 17 and 60% respectively. Weight loss, morphology, crystallinity and mechanical properties were studied. The kinetic study on the enzymatic degradation of PCL porous samples depends on porosity, suggesting that degradation took place on the surface, not suffering bulk degradation. The non‐dependence on crystallinity indicates that degradation occurred in both phases, amorphous and crystalline, at the same time.
An Atomistic Modeling and Quantum Mechanical Approach to the Hydrolytic Degradation of Aliphatic Polyesters
Authors: Entrialgo‐Castaño María , Salvucci Anthony E. , Lendlein Andreas , Hofmann Dieter 
Published: August 2008

AbstractThis paper reports computational simulations at two different scales employed to investigate the hydrolytic degradation of two homopolyesters: polyglycolide, PGA and poly(L‐lactide), PLLA. Atomistic bulk models were used to investigate the dry and various hydrated states of the two systems. In addition, the first moments of contact between the polymers and water were studied employing atomistic interface models. A higher affinity of water to polyglycolide in comparison with poly(L‐lactide) was observed, while diffusion of water was found to be lower in the first polymer. Quantum chemical calculations for the first step of the water‐assisted hydrolysis revealed a higher resistance to hydrolytical scission of the L‐lactyl units in comparison to glycolyl units.
Biomedical Investigations of Biodegradable PHAs
Authors: Shishatskaya Ekaterina I. 
Published: August 2008

AbstractThis work is a review of the results of biomedical studies of polymer devices (films, fibers, microparticles, 3D implants) made from resorbable PHAs synthesized by the bacterium Wautersia (Ralstonia) eutropha B5786, using the technology developed at the Institute of Biophysics of the Siberian Branch of the Russian Academy of Sciences. Two types of PHAs – polyhydroxybutyrate (PHB) and a hydroxybutyrate/hydroxyvalerate copolymer (PHB/PHV) – have been proven to be biocompatible in vitro in cultures of fibroblasts, endothelial cells, hepatocytes, and osteoblasts, and in short‐ and long‐duration experiments on animals. Polymer films and membranes have been found to be usable as scaffolds for functioning cells and monofilament suture fibers – for stitching muscular‐fascial wounds and in abdominal surgery. Ectopic bone formation assay and experiments with the model of segmental osteotomy showed that 3D PHB and PHB/HA implants can be used for reparative osteogenesis. The paper reports beneficial results of using polymers to repair bone defects in oral surgery.
In Vivo Justification of Using Endobiliary Stents Made of Polyhydroxyalkanoates
Authors: Markelova N.M. , Shishatskaya E.I. , Vinnik Y.S. , Cherdantsev D.V. , Beletskiy I.I. , Kuznetsov M.N. , Zykova L.D. 
Published: August 2008

AbstractTreatment of patients with mechanical jaundice (MJ) has been one of the topical problems of current medicine. The fraction of patients having MJ of oncologic character that can undergo radical surgery does not exceed 25–30%. A way out of such situation is to use minimally invasive endobiliary interventions, the main type of which is endoprosthesis replacement of bile duct lumens. The aim of the work was to study the biological properties of the experimental models of polymer stents made of PHA for endobiliary prosthetics and to investigate the biological properties of PHA suture material for forming of biliary‐enteric anastomoses (cholecystoduodenostomy). Experiments were performed on 20 adult mongrel dogs, weighing 10–12 kg. The animals were divided to three groups: the negative control group (intact animals); the positive control group (the animals with implanted endobiliary silicon stents); and the experimental group (the animals with the PHA stents). The animals were monitored for 100 days. The clinical blood analysis was made before the operation, on day 7, 30, 60 and 100 days. During autopsy the presence of exudate, commissural process in the free abdominal cavity and subhepatic spatium, the appearance of choledoch where the prosthesis was located, as well as the appearance of cholecystoenterostomy, liver and duodenum. We did not found any signs of inflammation, cicatrical changes were estimated in the free abdominal cavity and subhepatic spatium. All implanted PHA stents were at their initial places of implantation. After the end of the experiment inflammatory reaction and anastomositis were absent. Macroscopic changes of liver and duodenum were also not detected. Liver function did not have any pathological deviations. These positive results give grounds to conclude that application of PHA as endobiliary stents in reconstructive surgery of bile passages and as suture material is a promising technology.
3D Plotted PCL Scaffolds for Stem Cell Based Bone Tissue Engineering
Authors: Yilgor Pinar , Sousa Rui A. , Reis Rui L. , Hasirci Nesrin , Hasirci Vasif 
Published: August 2008

AbstractThe ability to control the architecture and strength of a bone tissue engineering scaffold is critical to achieve a harmony between the scaffold and the host tissue. Rapid prototyping (RP) technique is applied to tissue engineering to satisfy this need and to create a scaffold directly from the scanned and digitized image of the defect site. Design and construction of complex structures with different shapes and sizes, at micro and macro scale, with fully interconnected pore structure and appropriate mechanical properties are possible by using RP techniques. In this study, RP was used for the production of poly(ε‐caprolactone) (PCL) scaffolds. Scaffolds with four different architectures were produced by using different configurations of the fibers (basic, basic‐offset, crossed and crossed‐offset) within the architecture of the scaffold. The structure of the prepared scaffolds were examined by scanning electron microscopy (SEM), porosity and its distribution were analyzed by micro‐computed tomography (µ‐CT), stiffness and modulus values were determined by dynamic mechanical analysis (DMA). It was observed that the scaffolds had very ordered structures with mean porosities about 60%, and having storage modulus values about 1 × 107 Pa. These structures were then seeded with rat bone marrow origin mesenchymal stem cells (MSCs) in order to investigate the effect of scaffold structure on the cell behavior; the proliferation and differentiation of the cells on the scaffolds were studied. It was observed that cell proliferation was higher on offset scaffolds (262000 vs 235000 for basic, 287000 vs 222000 for crossed structure) and stainings for actin filaments of the cells reveal successful attachment and spreading at the surfaces of the fibers. Alkaline phosphatase (ALP) activity results were higher for the samples with lower cell proliferation, as expected. Highest MSC differentiation was observed for crossed scaffolds indicating the influence of scaffold structure on cellular activities.
Evaluation of Chitosan/Biphasic Calcium Phosphate Scaffolds for Maxillofacial Bone Tissue Engineering
Authors: Urkmez Aylin Sendemir , Clark Sherrie G. , Wheeler Matthew B. , Goldwasser Michael S. , Jamison Russell D. 
Published: August 2008

AbstractPorous, 3D chitosan/biphasic calcium phosphate (BCP) scaffolds were used to prepare tissue engineering constructs for maxillofacial bone tissue reconstruction. Mesenchymal stem cells (MSC's) were seeded and cultured on clinically relevant sized scaffolds.In vitroengineered constructs facilitated the healing of mandibular defects in pigs if accompanied with delivery of basic fibroblast growth factor (bFGF).