bluuebunny/crossref_metadata_2025 huggingface dataset:
Dissimilar Differentiation of Mesenchymal Stem Cells from Bone Marrow, Umbilical Cord Blood, and Adipose Tissue
Authors: Rebelatto C. K. , Aguiar A. M. , Moretão M. P. , Senegaglia A. C. , Hansen P. , Barchiki F. , Oliveira J. , Martins J. , Kuligovski C. , Mansur F. , Christofis A. , Amaral V. F. , Brofman P. S. , Goldenberg S. , Nakao L. S. , Correa A.
Published: April 2008

Mesenchymal stem cells (MSCs) have been investigated as promising candidates for use in new cell-based therapeutic strategies such as mesenchyme-derived tissue repair. MSCs are easily isolated from adult tissues and are not ethically restricted. MSC-related literature, however, is conflicting in relation to MSC differentiation potential and molecular markers. Here we compared MSCs isolated from bone marrow (BM), umbilical cord blood (UCB), and adipose tissue (AT). The isolation efficiency for both BM and AT was 100%, but that from UCB was only 30%. MSCs from these tissues are morphologically and immunophenotypically similar although their differentiation diverges. Differentiation to osteoblasts and chondroblasts was similar among MSCs from all sources, as analyzed by cytochemistry. Adipogenic differentiation showed that UCB-derived MSCs produced few and small lipid vacuoles in contrast to those of BM-derived MSCs and AT-derived stem cells (ADSCs) (arbitrary differentiation values of 245.57 ± 943 and 243.89 ± 145.52 μm2 per nucleus, respectively). The mean area occupied by individual lipid droplets was 7.37 μm2 for BM-derived MSCs and 2.36 μm2 for ADSCs, a finding indicating more mature adipocytes in BM-derived MSCs than in treated cultures of ADSCs. We analyzed FAPB4, ALP, and type II collagen gene expression by quantitative polymerase chain reaction to confirm adipogenic, osteogenic, and chondrogenic differentiation, respectively. Results showed that all three sources presented a similar capacity for chondrogenic and osteogenic differentiation and they differed in their adipogenic potential. Therefore, it may be crucial to predetermine the most appropriate MSC source for future clinical applications.
Homeostatic Action of Adenosine A3and A1Receptor Agonists on Proliferation of Hematopoietic Precursor Cells
Authors: Hofer Michal , Pospíšil Milan , Znojil Vladimír , Holá Jiřina , Štreitová Denisa , Vacek Antonín
Published: April 2008

Two adenosine receptor agonists, N6-(3-iodobenzyl)adenosine-5′-N-methyluronamide (IB-MECA) and N6-cyclopentyladenosine (CPA), which selectively activate adenosine A3and A1receptors, respectively, were tested for their ability to influence proliferation of granulocytic and erythroid cells in femoral bone marrow of mice using morphological criteria. Agonists were given intraperitoneally to mice in repeated isomolar doses of 200 nmol/kg. Three variants of experiments were performed to investigate the action of the agonists under normal resting state of mice and in phases of cell depletion and subsequent regeneration after treatment with the cytotoxic drug 5-fluorouracil. In the case of granulopoiesis, IB-MECA 1) increased by a moderate but significant level proliferation of cells under normal resting state; 2) strongly increased proliferation of cells in the cell depletion phase; but 3) did not influence cell proliferation in the regeneration phase. CPA did not influence cell proliferation under normal resting state and in the cell depletion phase, but strongly suppressed the overshooting cell proliferation in the regeneration phase. The stimulatory effect of IB-MECA on cell proliferation of erythroid cells was observed only when this agonist was administered during the cell depletion phase. CPA did not modulate erythroid proliferation in any of the functional states investigated, probably due to the lower demand for cell production as compared with granulopoiesis. The results indicate opposite effects of the two adenosine receptor agonists on proliferation of hematopoietic cells and suggest the plasticity and homeostatic role of the adenosine receptor expression.
STRONG Μ‐FASTER CONVERGENCE AND STRONG Μ‐ACCELERATION OF CONVERGENCE BY REGULAR MATRICES
Authors: Aasma A.
Published: April 2008

The present paper continues the study of acceleration of convergence started in the paper [A. Aasma, Proc. Estonian Acad. Sci. Phys. Math., 2006, 55, 4, 195–209]. The new, non‐classical convergence acceleration concept, called strong μ‐acceleration of convergence (μ is a positive monotonically increasing sequence), is introduced. It is shown that this concept allows to compare the speeds of convergence for a larger set of sequences than the classical convergence acceleration concept. Regular matrix methods are used to accelerate the convergence of sequences.
A COMPARISON OF HEURISTIC METHODS FOR POLYNOMIAL REGRESSION MODEL INDUCTION
Authors: Jekabsons G. , Lavendels J.
Published: April 2008

We compare four different heuristic methods for polynomial regression model induction. The methods are very different in their approaches. Our main concern in this study is in the differences of candidate model spaces the methods deal with (completely predefined versus non‐predefined), as well as search strategies used. We investigate the advantages and disadvantages of the approaches represented by the methods in terms of predictive error, complexity of the induced models and required computational resources. For empirical comparisons, we use twelve test problems.
ON THE STABILITY OF PIECEWISE POLYNOMIAL COLLOCATION METHODS FOR SOLVING WEAKLY SINGULAR INTEGRAL EQUATIONS OF THE SECOND KIND
Authors: Kangro R. , Kangro I.
Published: April 2008

Piecewise polynomial collocation methods on special nonuniform grids are efficient methods for solving weakly singular Fredholm and Volterra integral equations but there is a widespread belief that those methods are numerically unstable in the case of large values of the nonuniformity parameter r. We show that this method by itself is stable and discuss some implementation problems that may lead to unstable behavior of numerical results.
ANALYTICAL METHODS FOR HEAT CONDUCTION IN COMPOSITES
Authors: Mityushev V. , Obnosov YU. , Pesetskaya E. , Rogosin S.
Published: April 2008

Analytical methods unifying the study of heat conduction in various type of composite materials are described. Analytical formulas for the effective (macroscopic) conductivity tensor are presented.
A genome wide linkage scan of metacarpal size and geometry in the Framingham Study
Authors: Karasik David , Shimabuku Nicole A. , Zhou Yanhua , Zhang Yuqing , Cupples L. Adrienne , Kiel Douglas P. , Demissie Serkalem
Published: April 2008

Bone geometry is a significant component of bone strength, and has a clinical utility in predicting fractures and quantifying bone loss. Bone geometry is known to have a substantial genetic component. We performed linkage analysis to identify chromosomal regions governing metacarpal bone geometry. A genome‐wide scan (with a set of 615 markers with spacing of ∼5.7 cM) was performed on 1,702 individuals from 330 extended families of the Framingham Study. Midshaft width was measured and several indices calculated, namely Metacarpal Cortical Thickness (MCT), Cortical Index (MCI), and Section Modulus (MZ), using digitized X‐rays of 1,380 participants (men, n = 666, mean age 55.2 yr, women, n = 714, 55.5 yr). Metacarpals 2, 3, and 4 were averaged. Heritability was significant for all indices, ranging from 0.51 to 0.72. Linkage analysis of indices adjusted for age, age2, and estrogen status in women, identified chromosomal regions 6p21, 9p21, 11q21‐q22, and Xq26‐Xq27, with LOD scores >2.0. Additional adjustment for smoking, height, and BMI, generally reduced the LOD scores. Finally, bivariate linkage analysis confirmed that a QTL on chr. 6 (51 cM) was shared by midshaft width and MZ (LOD = 2.40, adjusted for all covariates). Neither MCT nor MCI shared linkage loci with width or MZ. In conclusion, we have identified chromosomal regions potentially linked to bone geometry. Genes in these regions may regulate bone geometry via effects on body size. Identification and subsequent characterization of loci for bone geometry can further elucidate the genetic contributions to bone's resistance to stress. Am. J. Hum. Biol., 2008. © 2008 Wiley‐Liss, Inc.
Study of degradation of organic coatings in seawater by using EIS and AFM methods
Authors: Zhang Feng , Liu Jingjun , Li Xiaoyu , Guo Ming
Published: April 2008

In this article, electrochemical behaviors and their topography observation for four organic coatings used in seawater, by using both electrochemical impedance spectroscopy (EIS) and atomic force microscopy (AFM) methods to study environment behaviors of different coatings as well as the effects of their film formation, pigments, and fillers on anticorrosion behaviors, were measured. The results show that polyurethane, epoxy, and chlorinated rubber coatings all present one capacitive loop in their tested EIS which contains phenomenally only one time constant, whereas alkyd coating presents two capacitive semicircle arcs. With two capacitive loops, the capacitive semicircle in the high frequency range represents barrier layer property, but the semicircle in the low frequency range represents corrosion reaction of metals under the film. Polyurethane coating used in seawater has well anticorrosion property in seawater immersion test. The appearance features of different layers are visible different between different layers of tested coatings at their surface topography. The property of polyurethane paint film coated on metal is better than other layers, and film of alkyd coating has many pits at its surface by observing the layer's images. AFM photos imaged have also been used to further detail surface topography for four organic coatings, and to approve effects of topography of these coatings on its electrochemical behaviors, from two views of both height and phase modes. It is beneficial to explain deeply the environment behaviors and degradation mechanism of organic coatings. To further study failure of these organic coatings and dynamic processes of corrosion of metal under the film, two equivalent circuit models, according to these tested EIS, have been suggested to explain the corrosive kinetics of these four coatings. To polyurethane, epoxy, and chlorinated rubber coatings used in seawater which have good protection effects for substrate metal, the diffusion process for water, from their layer's surface to interface of film/metal, is mainly controlled factor for degradation. However, the electrochemical reaction process has may become a control procedure for corrosion of alkyd coated metal. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Honeybee corpses as an available source of chitin
Authors: Draczynski Zbigniew
Published: April 2008

Corpses of naturally died honeybees were used as a raw material for chitin isolation. Process of deproteinization of the powder made from clean bee corpses was carried out in the presence of 1M NaOH at 80°C. Influence of time of alkaline treatment on the yield and molar mass of chitin was studied and optimal conditions of proteins removal were found. Process of final depigmentation of protein‐free remainders was carried out using oxidization–reduction reagents. Dependences of the yield of reaction and molar mass of the obtained chitin samples from concentration of oxidizing agent KMnO4 and from time of discoloring treatment were determined. Final product—high quality chitin with molar masses in range from 318 × 103 to 424 × 103 Da—was obtained in amount of 18% from initial mass of honeybee corpses. Chemical structure of chitin was determined in 1H NMR investigation. It was found that honeybee chitin has high degree of acetylation of about 96%. FTIR spectra of honeybee chitin did not differ from FTIR spectrum of control sample of shrimps chitin with degree of acetylation about 95%. Results of quantitative determination of isolated chitin and its molar characteristic showed that applied treatment of honeybee corpses allowed to acquire successfully chitin of high quality in wide range of molar masses. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Microanatomy of the Palatal Mucosa of the Semiaquatic Malayan Box Turtle, Cuora amboinensis, and Functional Implications
Authors: Heiss Egon , Plenk Hanns , Weisgram Josef
Published: April 2008

Scanning Electron Microscopy (SEM) revealed that the palate of Cuora amboinensis has a flat surface with keratinized and non‐keratinized regions. Keratinization is reflected in disc‐shaped keratinized dead cells with rough microplicae on the surface, and is concentrated close to the rhamphotheca. The surface of the non‐keratinized hexagonal epithelial cells is dotted with microvilli and sometimes with cilia. Taste buds are present both in lightly keratinized and non‐keratinized regions and exhibit a crater‐like shape. Light microscopy shows the different tissue layers of the oral mucosa and the different epithelial structures. In keratinized regions, keratinocytes mature from basal to superficial, where they build up keratin layers of varying thickness. In non‐keratinized regions, the epithelial cells are arranged in a stratified fashion, and cuboidal to cylindric cells form a superficial layer. Goblet cells appear to be diffusely distributed, but are often organized in goblet cell fields which can be folded into crypts. Taste buds consist of slender epithelial cells, exhibit the typical barrel‐like shape and are specially concentrated in the anterior, praechoanal palate. This anterior concentration of taste buds is shown by kinematographic analysis to correlate with the food prehension mode in Cuora amboinensis. The lamina propria of the palatal mucosa consists of loose connective tissue with inflammatory cells between capillaries. All these structures of the oral mucosa act as a functional entity and help determine how successfully an organism adapts ecologically to the environment. Anat Rec, 291:876‐885, 2008. © 2008 Wiley‐Liss, Inc.
Functional Connectivity of the Secondary Somatosensory Cortex of the Rat
Authors: Liao Chia‐Chi , Yen Chen‐Tung
Published: April 2008

The hierarchical relationship of the rat primary somatosensory cortex (S1) and secondary somatosensory cortex (S2) is controversial. The existence of a direct thalamocortical projection from ventral posterolateral thalamic nucleus (VPL) to S2 is a key factor in determining the relative position of S2 in the processing flow. In this study, the inter‐connections of forepaw and hindpaw representations in VPL, S1, and S2 were examined by neuroanatomical tracing and electrophysiological approaches. In the tracing experiments, VPL, S1, and S2 were electrophysiologically identified, and then iontophoretically injected with biotinylated dextran amine (BDA, a bi‐directional tracer). In the double‐labeling experiments, two of the following retrograde tracers—BDA, Rhodamine dextran (RD), and/or Fluoro‐Gold (FG)—were injected into homotypical S1 and S2 forepaw representations simultaneously. In the electrophysiological studies, paired somatic evoked multiunit responses in S1 and S2 were compared. Our results revealed that: (1) VPL forepaw and hindpaw neurons projected to corresponding S1 and S2 areas in a parallel and somatotopic manner; (2) very low percentage of double projecting VPL neurons were found, indicating parallel and independent pathways from forepaw VPL to S1 and S2; (3) forepaw S1 and S2 were symmetrically and reciprocally connected; (4) response latencies of the S1 and S2 multiunits to forepaw stimulation were in accordance with a direct and parallel pathway. This study provides further evidence to support the equivalent hierarchy of S1 and S2 in processing sensory information of the rat. Anat Rec, 291:960–973, 2008. © 2008 Wiley‐Liss, Inc.
Morphology and Innervation of the Human Cremaster Muscle in Relation to its Function
Authors: Kayalioglu Gulgun , Altay Baris , Uyaroglu Feray Gulec , Bademkiran Fikret , Uludag Burhanettin , Ertekin Cumhur
Published: April 2008

The electromyographic properties of the cremaster muscle (CM) are quite different from other skeletal muscles. It shows excessive spontaneous discharges, and the motor unit shape and firing frequency of the CM muscle differ from that of limb muscles. In this study, CM of six adult cadavers and six orchiectomy specimens were used to reveal the detailed histology of the muscle and provide an anatomophysiological explanation for these unusual electromyographic properties. Routine histochemical stains revealed the CM was composed of several distinct bundles of smooth and striated muscle fibers within connective tissue. The smooth muscle fibers that were more profuse than previously known and were not arranged in layers, but widely dispersed between striated muscle fibers. Bielschowsky silver staining technique, anti‐neurofilament and anti‐synaptophysin immunostaining showed the presence of multiple motor end‐plates observed as a series of small dots or lines running along the striated muscle fibers and several nerve endings on a single muscle fiber. Myosin immunostaining confirmed the CM is a slow‐twitch muscle, and α‐actin smooth muscle immunostaining confirmed the presence of a large number of smooth muscle fibers. There were also small multipolar neurons forming nerve plexuses between smooth muscle fibers. Anti‐GFAP immunostaining confirmed the presence of glial cells similar to astrocytes. In conclusion, the findings of this detailed anatomical study showed the CM, widely known as a striated muscle, contains a large number of smooth muscle fibers, and the spontaneous electromyographic discharges are due to the presence of multiple motor end‐plates and dense innervation. Anat Rec,291:790‐796, 2008. © 2008 Wiley‐Liss, Inc.
The characteristics of the band‐pass filtered time series of the zonal averages of monthly mean values based on ERA‐40 reanalysis
Authors: Lim G.‐H. , Shim Taehyoun , Suh A.‐S. , Lee D.‐I. , Choi Wookap
Published: April 2008

By band‐passing the European Center reanalysis monthly mean values, we examined the frequency components of 2–3 years in height, latitude, and time domains. In the lower stratosphere, these frequencies have the typical shape of a stratospheric quasi‐biennial oscillation (QBO). We also found significant power of the same frequency components of specific humidity near the surface over the tropics, which can be regarded as an evidence of the effects of the QBO on the lower troposphere. Such variation of specific humidity might be caused by a change of the mid‐latitude branch of the Hadley circulation instead of direct control through the equatorial upper troposphere. Copyright © 2008 Royal Meteorological Society
Rijnland case study: hindcast experiment for anticipatory water‐system control
Authors: van Andel Schalk J. , Lobbrecht Arnold H. , Price Roland K.
Published: April 2008

Flooding problems in low‐lying controlled water systems are being addressed. A methodology is described in which flood‐control strategies based on ensemble precipitation forecasts and hydrological models are developed using simulation and verification analysis. The methodology is applied to the Rijnland channelled storage basin in the Netherlands. A control strategy for lowering the water levels in anticipation of heavy rainfall, and based on 3‐day ensemble water level forecasts, is demonstrated for a heavy rain event in September 1998. The results show that the measured peak is successfully reduced and false alarms do not occur before the precipitation event. Copyright © 2008 Royal Meteorological Society
Seasonal hydrologic predictions of low‐flow conditions over eastern USA during the 2007 drought
Authors: Li Haibin , Luo Lifeng , Wood Eric F.
Published: April 2008

A seasonal streamflow monitoring and forecasting component is implemented into the Drought Monitoring and Prediction System (Luo and Wood, 2007a), which supplements the existing soil‐moisture‐based analysis framework by providing real‐time streamflow monitoring and forecasting up to 6 months lead time. Evaluations were conducted over four basins in eastern USA to understand the forecast skill of the system for the extensive hydrologic droughts in 2007. Consistent with the agricultural drought forecasts reported by Luo and Wood (2007a), the streamflow subsystem can forecast low‐flow conditions for up to three months in advance, with Brier scores ranging from 0.10 to 0.49. Copyright © 2008 Royal Meteorological Society
Factors' correlation in the Heath–Jarrow–Morton interest rate model
Authors: Tchuindjo Leonard
Published: April 2008

We propose a new derivation of the Heath–Jarrow–Morton risk‐neutral drift restriction that takes into account nonzero instantaneous correlations between factors. The result allows avoiding the orthogonalization of factors and provides an approach by which interest rate derivatives can be priced by preserving the economic meaning of each underlying factor. An application is given for the term structure of credit‐risky bonds, driven by two correlated factors—the risk‐free forward rate and the forward credit spreads. Copyright © 2008 John Wiley & Sons, Ltd.
Organocatalytic Multicomponent α‐Methylenation/Diels–Alder Reactions: A Versatile Route to Substituted Cyclohexenecarbaldehyde Derivatives
Authors: Zou Yue , Wang Quanrui , Goeke Andreas
Published: April 2008

This article describes the design and optimization of an effective organocatalytic three‐component domino α‐methylenation/Diels–Alder reaction to produce vinyl‐substituted cyclohexenecarboxaldehydes in a highly regioselective fashion. In these one‐pot transformations, 2‐formyl‐1,3‐butadienes (4) were prepared in situ from α,β‐unsaturated aldehydes and formalin and were subsequently trapped with a variety of buta‐1,3‐dienes. The outcomes of the reactions were dependent on the electronic properties of the dienes. 1‐Vinylcyclohexenecarbaldehydes 6 were formed by use of acyclic electron‐rich dienes, while the initially formed cycloadducts of 4 with cyclopentadiene underwent Cope rearrangements, leading to the formation of tetrahydro‐3H‐indene‐5‐carbaldehyde compounds 7. The mechanisms involved in these reactions were deduced from experimental findings. Furthermore, the method was also extended to one‐pot domino methylenation/Diels–Alder reactions of dihydrofurans and dihydropyrans to yield spirocyclic lactols 22. In these reactions, the unstable intermediate hydroxyethyl and hydroxypropyl acroleins behaved as dienophiles, undergoing cycloaddition reactions with dienes with good yields and selectivities. The wide variety of functionalized 1‐vinylcyclohex‐3‐enecarbaldehydes 6, 4‐vinylcyclohex‐1‐enecarbaldehydes 7, and spiro lactols 22 generated through the use of these organocatalytic domino processes as a diversity‐oriented synthesis provided useful intermediates for the construction of novel odorants.
Monomer versus Alcohol Activation in the 4‐Dimethylaminopyridine‐Catalyzed Ring‐Opening Polymerization of Lactide and Lactic O‐Carboxylic Anhydride
Authors: Bonduelle Colin , Martín‐Vaca Blanca , Cossío Fernando P. , Bourissou Didier
Published: April 2008

Model reactions for the 4‐dimethylaminopyridine (DMAP)‐catalyzed ring‐opening polymerization of lactide and the corresponding lactic O‐carboxylic anhydride (lacOCA) have been studied computationally at the B3LYP/6–31G(d) level of theory. The solvent effect of dichloromethane was taken into account through PCM/SCRF single‐point calculations at the B3LYP/6–31G(d) level of theory. In marked contrast with that predicted for the reaction of alcohols with acetic anhydride, the mechanism in which nucleophilic activation of the monomer involving acylpyridinium intermediates was found to be energetically less favorable than the base activation of the alcohol through hydrogen bonding. The concerted pathway for the ring‐opening of lactide and lacOCA was shown to compete with the traditional stepwise mechanism involving tetrahedral intermediates. Furthermore, DMAP is proposed to act as a bifunctional catalyst through its basic nitrogen center and an acidic ortho‐hydrogen atom.
Synthesis, Characterization, and Photophysical Properties of 2‐Hydroxybenzaldehyde [(1E)‐1‐pyridin‐2‐ylethylidene]hydrazone and Its Rhenium(I) Complexes
Authors: Barbazán Paula , Carballo Rosa , Covelo Berta , Lodeiro Carlos , Lima João Carlos , Vázquez‐López Ezequiel M.
Published: April 2008

The 2‐hydroxybenzaldehyde [(1E)‐1‐pyridin‐2‐ylethylidene]hydrazone (HL2) ligand was prepared and its rhenium(I) complexes [ReX(CO)3(HL2)] were obtained by reaction with fac‐[ReX(CO)3(CH3CN)2] (X = Cl, Br) in chloroform. The compounds were characterized by elemental analysis, mass spectrometry, and IR, UV/Vis, and 1H NMR spectroscopy. Furthermore, the structures were also established by X‐ray diffraction. The aromatic rings are almost coplanar in the ligand structure, and the configuration around the hydrazone group is strongly dominated by the presence of an intramolecular hydrogen bond between the OH group and the hydrazinic nitrogen atom N1. The rhenium center is coordinated through the pyridine and hydrazinic nitrogen atoms to give a five‐membered chelate ring. In addition, the free ligand shows interesting luminescence properties. The effect of the metal coordination on the photophysical behavior of the resulting complex was also studied.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Alkyne Substitution on Cobaltocenium Triflates
Authors: von der Grün Mareile , Gleiter Rolf , Rominger Frank
Published: April 2008

Cobaltocenium triflates consisting of a CpCo‐capped η5‐1‐trifluoromethylsulfonyloxy‐2,3,4,5‐tetrapropylcyclopentadienyl ring were substituted at the Cp ring by a trialkylsilylethynyl group to yield the R–CpCo capped tetra‐n‐propylcyclopentadienone with R = C2SiMe3 (11a) and R = C2SiEt3 (11b). The parent system with R = C2H (11c) was generated by hydrolyzing the SiR3 groups of 11a and 11b. The trialkylsilyl‐1,3‐butadiyne derivatives with alkyl = CH3 (11d) and alkyl = C2H5 (11e) were derived from 11c by using a Cadiot–Chodkiewicz coupling with bromo(triethylsilyl)acetylene. Removal of the SiEt3 protecting group led to 11f. The alkynes 11c and 11f could be dimerized to 13a and 13b by a Hay coupling. These results were confirmed by X‐ray diffraction studies on the starting materials 7, 8, and 12 as well as the derivatives 11c, 11f, and 13a.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Human Y‐chromosome haplotyping by allele‐specific polymerase chain reaction
Authors: Gayden Tenzin , Regueiro Maria , Martinez Laisel , Cadenas Alicia M. , Herrera Rene J.
Published: April 2008

We describe the application of allele‐specific PCR (AS‐PCR) for screening biallelic markers, including SNPs, within the nonrecombining region of the human Y‐chromosome (NRY). The AS‐PCR method is based on the concept that the perfectly annealed primer–template complex is more stable, and therefore, more efficiently amplified under the appropriate annealing temperature than the complex with a mismatched 3′‐residue. Furthermore, a mismatched nucleotide at the primer's 3′‐OH end provides for a poor extension substrate for Taq DNA polymerase, allowing for discrimination between the two alleles. This method has the dual advantage of amplification and detection of alleles in a single expeditious and inexpensive procedure. The amplification conditions of over 50 binary markers, mostly SNPs, that define the major Y‐haplogroups as well as their derived lineages were optimized and are provided for the first time. In addition, artificial restriction sites were designed for those markers that are not selectively amplified by AS‐PCR. Our results are consistent with allele designations derived from other techniques such as RFLP and direct sequencing of PCR products.
Simultaneous separation of basic and acidic proteins using 1‐butyl‐3‐methylimidazolium‐based ion liquid as dynamic coating and background electrolyte in capillary electrophoresis
Authors: Wu Xiaoping , Wei Weiping , Su Qingmei , Xu Liangjun , Chen Guonan
Published: April 2008

1‐Butyl‐3‐methylimidazolium tetrafluoroborate ionic liquids (1B‐3MI‐TFB ILs) were employed as a coating material and BGE in CE for simultaneous separation of basic and acidic proteins such as lysozyme, cytochrome C, ribonuclease A, albumin, and α‐lactalbumin. 1B‐3MI‐TFB ILs effectively reversed the surface charges on the capillary inner surface, preventing the adsorption of postively charged proteins onto the silica surface, as well as associated with proteins, thus benefiting the separation efficiencies and reproducibility. Consequently, simultaneous baseline separation of five proteins was achieved within 14 min by using 10 mM of 1B‐3MI‐TFB ILs as dynamic coating and the only running electrolyte at the voltage of +20 kV. The proposed coating technique is simple, less time‐consuming, reproducible, and also stable enough for proteins separation without the need of additives. Symmetrical peaks with efficiencies up to 670 000 plates/m were obtained. Recoveries of proteins with RSD (for migration times) of 0.23–0.42% (run‐to‐run) and 2.5–3.8% (day‐to‐day) were achieved, respectively. The applicability of the proposed method in proteins separation was evaluated by the separation of egg white samples.
Telomeric 3′ overhangs in chronic HBV‐related hepatitis and hepatocellular carcinoma
Authors: Lee Jae‐Eun , Oh Bong‐Kyeong , Choi Jinsub , Park Young Nyun
Published: April 2008

Telomeric 3′ overhang is a key component of telomere structure, but little is known about its role in hepatocarcinogenesis. We examined the 3′ overhang and telomere length, mRNA levels of hTERT, POT1, TRF1 and cytokeratin 19 (CK19) in 41 hepatitis B virus (HBV)‐related hepatocellular carcinomas (HCCs) and adjacent non‐HCCs of B viral chronic hepatitis/cirrhosis. 3′ overhang length was positively correlated with telomere length (p < 0.001). In non‐HCCs, the 3′ overhang shortened with increasing age (p = 0.043). Twenty‐six HCCs had shorter and 15 HCCs had longer 3′ overhangs than the adjacent non‐HCCs. The mRNA levels of hTERT, POT1 and TRF1 were upregulated in HCCs than in non‐HCCs. HCCs with lengthened 3′ overhangs expressed higher hTERT mRNA levels than those with shortened 3′ overhangs, when compared to 3′ overhangs in non‐HCCs (p = 0.044). POT1 and TRF1 showed no significant difference according to the 3′ overhangs. HCCs with long 3′ overhangs had higher mitosis (p = 0.046) and more frequent multipolar mitosis compared to those with short 3′ overhangs (p = 0.034). HCCs with high cytokeratin 19 mRNA levels, a marker for hepatic progenitor cells, had longer 3′ overhangs than HCCs with low cytokeratin 19 mRNA levels (p= 0.019). In conclusion, the 3′ overhang erosion might be closely related to the number of cell divisions in telomerase‐negative hepatocytes of chronic hepatitis/cirrhosis. In telomerase‐positive HCCs, an altered 3′ overhang are involved in HBV‐related hepatocarcinogenesis and hTERT might be involved in regulation of 3′ overhang. © 2008 Wiley‐Liss, Inc.
Hydraulic Management Drives Heat Budgets and Temperature Trends in a Mediterranean Reservoir
Authors: Moreno‐Ostos Enrique , Marcé Rafael , Ordóñez Jaime , Dolz Josep , Armengol Joan
Published: April 2008

By contrast to the more regular and predictable temperate lakes, heat budgets and temperature dynamics in Mediterranean reservoirs are characterized by a marked interannual variability. In the present paper, the heat content, annual Birgean heat budget (ABHB), and thermal structure of Sau Reservoir were examined during a period of hypolimnetic withdrawal between 1980 and 1985, and during a period of withdrawal at intermediate depths between 1996 and 2003. The two study periods were also characterized by a wide range of stored water volume fluctuations. Results were used to develop and validate an empirical model to predict annual and monthly heat dynamics statistics and mixed layer depth as a function of hydraulic management parameters such as water volume and selective withdrawal depth. During the hypolimnetic withdrawal period elevated ABHB and deep mixed layer depths were recorded in the reservoir, which behaved as a heat trap. By contrast, intermediate depth withdrawal promoted a shallower and more stable thermocline, thus increasing the cold hypolimnetic water volume and decreasing heat content and ABHB. The study reveals that hydraulic management constitutes the main driver of the heat and thermal dynamics in reservoirs with multiple withdrawal outlets. By contrast with the increasing temperature trends recorded in many natural lakes, the hydraulic management in Sau Reservoir induced a progressive reduction in water temperature and heat content in the system, thus partially counteracting the possible deleterious effects of global warming. Our intensive study in a single, highly‐dynamic ecosystem constitutes a new approximation to the study of thermal structure and heat dynamics in water bodies. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Finding of Pleuroxus smirnovi sp. nov. from the Pamir Region Revealed Today's Imperfect State of Systematics and Biogeography of the Chydorinae (Cladocera: Chydoridae)
Authors: Kotov Alexey A.
Published: April 2008

Pleuroxus smirnovi sp. nov. (Cladocera: Chydoridae) is found in a temporary freshwater body near Lake Zor‐Kul, the Pamirs (territory of Tajikistan). This large, brownish chydorine, with especially high body compressed laterally and supplied with a sharp dorsal keel, “untypical” of the genus Pleuroxus, at the same time, has the number of setae in filter plates of gnathobases II–V typical of this genus, namely 8‐8‐6‐4. My finding of P. smirnovi sp. nov. is a new evidence of an incomplete faunistic coverage and an imperfect state of today's systematics of the subfamily Chydorinae, because this new species has a set of characters apparently intermediate between the genera Pleuroxus Baird, 1843, Plurispina Frey, 1991 and Planicirculus Frey, 1991. Previously, large, compressed, and keeled chydorines were regarded as exclusively Australian, agreeing with ideas on a high endemism of the Australian cladoceran fauna. But after my finding of P. smirnovi sp. nov. we can speak only on “a predominantly Australian” distribution of such forms. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Corrosion resistance and cytocompatibility of biodegradable surgical magnesium alloy coated with hydrogenated amorphous silicon
Authors: Xin Yunchang , Jiang Jiang , Huo Kaifu , Tang Guoyi , Tian Xiubo , Chu Paul K.
Published: April 2008

The fast degradation rates in the physiological environment constitute the main limitation for the applications of surgical magnesium alloys as biodegradable hard‐tissue implants. In this work, a stable and dense hydrogenated amorphous silicon coating (a‐Si:H) with desirable bioactivity is deposited on AZ91 magnesium alloy using magnetron sputtering deposition. Raman spectroscopy and Fourier transform infrared spectroscopy reveal that the coating is mainly composed of hydrogenated amorphous silicon. The hardness of the coated alloy is enhanced significantly and the coating is quite hydrophilic as well. Potentiodynamic polarization results show that the corrosion resistance of the coated alloy is enhanced dramatically. In addition, the deterioration process of the coating in simulated body fluids is systematically investigated by open circuit potential evolution and electrochemical impedance spectroscopy. The cytocompatibility of the coated Mg is evaluated for the first time using hFOB1.19 cells and favorable biocompatibility is observed. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009
Heparin activates Wnt signaling for neuronal morphogenesis
Authors: Colombres Marcela , Henríquez Juan Pablo , Reig Germán F. , Scheu Jessica , Calderón Rosario , Alvarez Alejandra , Brandan Enrique , Inestrosa Nibaldo C.
Published: April 2008

Wnt factors are secreted ligands that affect different aspects of the nervous system behavior like neurodevelopment, synaptogenesis and neurodegeneration. In different model systems, Wnt signaling has been demonstrated to be regulated by heparan sulfate proteoglycans (HSPGs). Whether HSPGs modulate Wnt signaling in the context of neuronal behavior is currently unknown. Here we demonstrate that activation of Wnt signaling with the endogenous ligand Wnt‐7a results in an increased of neurite outgrowth in the neuroblastoma N2a cell line. Interestingly, heparin induces glycogen synthase kinase‐3β (GSK‐3β) inhibition, β‐catenin stabilization and morphological differentiation in both N2a cells and in rat primary hippocampal neuronal cultures. We also show that heparin modulates Wnt‐3a‐induced stabilization of β‐catenin. Several extracellular matrix and membrane‐attached HSPGs were found to be expressed in both in vitro neuronal models. Changes in the expression of specific HSPGs were observed upon differentiation of N2a cells. Taken together, our findings suggest that HSPGs may modulate canonical Wnt signaling for neuronal morphogenesis. J. Cell. Physiol. 216: 805–815, 2008, © 2008 Wiley‐Liss, Inc.
Symposium on the evolution and development of the vertebrate head
Authors: Depew Michael J. , Olsson Lennart
Published: April 2008

Among the symposia held at the seminal meeting of the European Society for Evolutionary Developmental Biology was one centered on the development and evolution of the vertebrate head, an exquisitely complex anatomical system. The articles presented at this meeting have been gathered in a special issue of the Journal of Experimental Zoology, and are here reviewed by the organizers of the symposia. These articles cover a breadth of subjects, including interactions between cells derived from the different germ layers, such as those underlying neural crest cell migration and fate and cranial muscle specification, as well as placode development and the origin, development, and evolution of important evolutionary innovations such as jaws and the trabecula cranii. In this introduction, we provide a short historical overview of themes of research into the fundamental organization, structure, and development of the vertebrate head, including the search for head segmentation and the relevance of the New Head Hypothesis, and subsequently present the topics discussed in each of the articles. This overview of the past and the present of head evo–devo is then followed by a glimpse at its possible future and a brief examination of the utility of the notions of heterochrony, heterotopy, and heterofacience in describing evolutionarily important changes in developmental events. J. Exp. Zool. (Mol. Dev. Evol.) 310B:287–293, 2008. © 2008 Wiley‐Liss, Inc.
A comparative molecular force spectroscopy study of homophilic JAM‐A interactions and JAM‐A interactions with reovirus attachment protein σ1
Authors: Vedula Sri Ram Krishna , Lim Tong Seng , Kirchner Eva , Guglielmi Kristen M. , Dermody Terence S. , Stehle Thilo , Hunziker Walter , Lim Chwee Teck
Published: April 2008

JAM‐A belongs to a family of immunoglobulin‐like proteins called junctional adhesion molecules (JAMs) that localize at epithelial and endothelial intercellular tight junctions. JAM‐A is also expressed on dendritic cells, neutrophils, and platelets. Homophilic JAM‐A interactions play an important role in regulating paracellular permeability and leukocyte transmigration across epithelial monolayers and endothelial cell junctions, respectively. In addition, JAM‐A is a receptor for the reovirus attachment protein, σ1. In this study, we used single molecular force spectroscopy to compare the kinetics of JAM‐A interactions with itself and σ1. A chimeric murine JAM‐A/Fc fusion protein and the purified σ1 head domain were used to probe murine L929 cells, which express JAM‐A and are susceptible to reovirus infection. The bond half‐life (t1/2) of homophilic JAM‐A interactions was found to be shorter ($k_{{\bf off}}^{\bf o} = 0.688 \pm 0.349\;{\bf s}^{ - 1} $) than that of σ1/JAM‐A interactions ($k_{{\bf off}}^{\bf o} = 0.067 \pm 0.041\;{\bf s}^{ - 1} $). These results are in accordance with the physiological functions of JAM‐A and σ1. A short bond lifetime imparts a highly dynamic nature to homophilic JAM‐A interactions for regulating tight junction permeability while stable interactions between σ1 and JAM‐A likely anchor the virus to the cell surface and facilitate viral entry. Copyright © 2008 John Wiley & Sons, Ltd.
The significance of ANXA7 expression and its correlation with poor cellular differentiation and enhanced metastatic potential of gastric cancer
Authors: Hsu Ping‐I , Huang Ming‐Shyan , Chen Hui‐Chun , Hsu Ping‐Ning , Lai Tsung‐Ching , Wang Jui‐Ling , Lo Gin‐Ho , Lai Kwok‐Hung , Tseng Ching‐Jiunn , Hsiao Michael
Published: April 2008

Background

Annexin‐A7 (ANXA7) exhibits biological and genetic properties expected of a tumor suppressor gene and may play a role in cancer progression. However, the ANXA7 expression in different histological subtypes of gastric adenocarcinomas and its correlation with invasive potentials has not been elucidated.

Methods

Immunohistochemical staining of ANXA7 for 84 primary gastric adenocarcinomas was performed, and data was correlated with clinicopathological parameters of patients.

Results

The ANXA7 expression was well correlated with the grade of differentiation of primary tumors. Its expression was detected in 100% (8/8), 64.9% (24/37), 66.7% (2/3), 31.9% (13/31), 0% (0/3), and 0% (0/2) of well‐differentiated tubular, moderately‐differentiated tubular, papillary, poorly differentiated, signet‐ring cell, and mucinous adenocarcinoma, respectively. According to the Lauren's classification, the ANXA7 expression was higher in intestinal type than in diffuse type tumor (71.9% vs. 6.1%, P = 0.003). The loss of expression of ANXA7 expression was significantly related to distant metastasis (P = 0.04). However, there were no significant associations between the ANXA7 expression and survival of cancer patients (P = 0.159).

Conclusions

A striking correlation between ANXA7 expression and cell differentiation of gastric cancer was observed. The loss of expression of ANXA7 is associated with distant metastasis. J. Surg. Oncol. 2008;97:609–614. © 2008 Wiley‐Liss, Inc.
1H and 13C NMR assignments of two new diaryl ethers phomopsides A and B from the mangrove endophytic fungus (ZZF08)
Authors: Tao Yiwen , Mou Chengbo , Zeng Xianjian , Xu Fang , Cai Jiwen , She Zhigang , Zhou Shining , Lin Yongcheng
Published: April 2008

Two new diaryl ethers, named phomopside A (1) and B (2), together with known excelsione (3) were isolated from the mangrove endophytic fungus Phomopsis sp. (ZZF08) obtained from the South China Sea coast. The structure of 1 was elucidated by NMR spectroscopy and confirmed by X‐ray crystallography. Compounds 2 and 3 were identified by NMR spectroscopy and comparing the spectroscopic data with literature values. In addition, the plausible biogenetic path of 1, 2 and 3 is discussed. Copyright © 2008 John Wiley & Sons, Ltd.
Gene expression profiling of single bovine embryos uncovers significant effects of in vitro maturation, fertilization and culture
Authors: Smith Sadie L. , Everts Robin E. , Sung Li‐Ying , Du Fuliang , Page Raymond L. , Henderson Boyd , Rodriguez‐Zas Sandra L. , Nedambale Tshimangadzo L. , Renard Jean‐Paul , Lewin Harris A. , Yang Xiangzhong , Tian X. Cindy
Published: April 2008

In vitro production (IVP) has been shown to affect embryonic gene expression and often result in large offspring syndrome (LOS) in cattle and sheep. To dissect the effects of in vitro maturation, fertilization and culture on bovine embryos, we compared the expression profiles of single blastocysts generated by: (1) in vitro maturation, fertilization and culture (IVF); (2) in vivo maturation, fertilization and in vitro culture (IVD); and (3) in vivo maturation, fertilization and development (AI). To conduct expression profiling, total RNA was isolated from individual embryos, linearly amplified and hybridized to a custom bovine cDNA microarray containing approximately 6,300 unique genes. There were 306, 367, and 200 genes differentially expressed between the AI and IVD, IVF and IVD, and AI and IVF comparisons, respectively. Interestingly, 44 differentially expressed genes were identified between the AI embryos and both the IVF and IVD embryos, making these potential candidates for LOS. There were 60 genes differentially expressed between the IVF embryos and the AI and IVD embryos. The Gene Ontology category “RNA processing” was over‐represented among the genes that were down‐regulated in the IVF embryos, indicating an effect of in vitro oocyte maturation/fertilization on the ability to transcribe maternal RNA stores. A culture effect on the expression of genes involved in translation was also observed by the comparison of AI with IVD embryos. Mol. Reprod. Dev. 76: 38–47, 2009. © 2008 Wiley‐Liss, Inc.
Perceived stress in survivors of suicide: Psychometric properties of the Perceived Stress Scale
Authors: Mitchell Ann M. , Crane Patricia A. , Kim Yookyung
Published: April 2008

The purpose of this study was to evaluate the psychometric properties of three versions of the Perceived Stress Scale (PSS; © American Sociological Association) in adults who had survived the death of a family member or significant other by suicide. Reliability and validity were examined. Exploratory factor analysis was conducted to assess dimensionality of the underlying constructs. All three versions of the PSS demonstrated acceptable reliability. Two shorter versions retained good psychometric properties and demonstrated convergent and concurrent validity with measures of posttraumatic stress symptoms and mental health quality of life. Factor analysis provided further evidence of their usefulness as brief and valid measures of perceived stress in acutely bereaved adult survivors of suicide. In a sub‐sample of closely related survivors, the psychometric properties of the 4‐item version of the PSS were retained. © 2008 Wiley Periodicals, Inc. Res Nurs Health 31:576–585, 2008
Receiving inconclusive genetic test results: An interpretive description of the BRCA1/2 experience
Authors: Maheu Christine , Thorne Sally
Published: April 2008

We examined the experience of 21 women diagnosed with breast or ovarian cancer who received inconclusive BRCA1/2 genetic test results. Although these women received similar information on the technical meaning of an inconclusive result, their interpretations of personal risk for a probable, inherited cancer mutation differed. Their interpretations ranged from confidence that they probably carried an undetected gene mutation to believing that their cancer had no genetic basis. Women drew from their personal experience with genetic testing and from distinctive perceptions and beliefs in attempting to understand their test results; they variously drew upon such evidence as observations of similarities and differences within familial breast/ovarian cancer patterns to explain their ultimate conclusions as to their own genetic status. © 2008 Wiley Periodicals, Inc. Res Nurs Health 31:553–562, 2008