bluuebunny/crossref_metadata_2025 huggingface dataset:
Adhesive biomaterials for tissue reconstruction
Authors: Lauto Antonio , Mawad Damia , Foster L. John R.
Published: September 2007

Tissue reconstruction and wound closure rely on sutures, staples and clips in current surgical procedures. These traditional devices are nonetheless unable to prevent leakage of fluids from a variety of tissue including blood vessels and dura mater. Furthermore, sutures are usually difficult to apply during minimal invasive surgery and often induce detrimental scarring that may impair healing. To overcome these disadvantages, biocompatible and biodegradable glues based on fibrin, polyethylene glycol (PEG) and cyanoacrylate have recently been used in patients to seal and repair tissue wounds. Cyanoacrylate glues create typically very strong tissue bonds but have mostly been applied externally for skin wound closure because of their residual cytotoxicity. Other adhesive biomaterials are also emerging; these glues and adhesives are usually based on proteins such as albumin and collagen or polysaccharides like chitosan; these are irradiated with coherent or non‐coherent light to trigger their adhesion to tissue. These biomaterial based devices offer significant advantages over sutures, such as their sealing or repairing ability, easy application modality and delivery in situ of compounds for accelerating wound healing. This paper reviews different tissue reconstruction strategies employing adhesive biomaterials currently used in surgical and experimental procedures. Copyright © 2007 Society of Chemical Industry
Adlayer structure of octa‐alkoxy‐substituted copper(II) phthalocyanine on Au(111) by electrochemical scanning tunneling microscopy
Authors: Wang Li , Ou‐Yang Liangyue , Yau Shueh‐Lin
Published: September 2007

Electrochemical scanning tunneling microscopy (ECSTM) has been used to examine the adlayer of octa‐alkoxy‐substituted copper(II) phthalocyanines (CuPc(OC8H17)8) on Au(111) in 0.1 M HClO4, where the molecular adlayer was prepared by spontaneous adsorption from a benzene solution containing this molecule. Topography STM scans revealed long‐range ordered, interweaved arrays of CuPc(OC8H17)8 with coexistent rectangular and hexagonal symmetries. High‐quality STM molecular resolution yielded the internal molecular structure and the orientation of CuPc(OC8H17)8 admolecules. These STM results could shed insight into the method of generating ordered molecular assemblies of phthalocyanine molecules with long‐chained substitutes on metal surface. Microsc. Res. Tech., 2008. © 2007 Wiley‐Liss, Inc.
Three‐dimensional refractive index reconstruction with quantitative phase tomography
Authors: Dragomir N.M. , Goh X.M. , Roberts A.
Published: September 2007

Optical tomography based on quantitative phase microscopy is used to determine nondestructively and with high spatial resolution the three‐dimensional (3D) refractive index distributions within optical fiber devices. After obtaining a series of phase images of the fiber as it is rotated around its longitudinal axis at regularly‐spaced angular positions, filtered backprojection is used to reconstruct a 3D map of the refractive index. The 3D refractive index distribution of the join region between two fusion spliced optical fibers is reconstructed with accuracy better than 10−3. Microsc. Res. Tech., 2008. © 2007 Wiley‐Liss, Inc.
Measuring the energy expenditure and water flux in free‐ranging alpacas (Lama pacos) in the peruvian andes using the doubly labelled water technique
Authors: Riek Alexander , Van Der Sluijs Leendert , Gerken Martina
Published: September 2007

Energy expenditure and water flux were measured in free‐ranging alpacas Lama pacos, a South American camelid, on natural pastures of the Peruvian Andes (altitude: 4,400 m above sea level). Water influx rate (WIR) was estimated in 16 males (age 2 years, weight 48.5±8.6 kg) labelled with 2H. In addition, the field metabolic rate (FMR) was measured in four of these animals labelled with both an oxygen (18O) and a hydrogen (2H) isotope. The WIR averaged 3.62 L H2O/day and the mean total body water 33.1 kg, equal to 68.2% of body weight (BW). The FMR of the four doubly labelled animals was 14.05 MJ/day. New allometric equations were calculated describing the relationships between WIR or FMR and BW, respectively, including published data on ruminants and the present alpaca results. The regression equation indicates that daily WIR scales to a similar metabolic size (kilograms of BW0.94) in alpacas than in wild or domesticated ruminants and camelids originating from arid and semiarid habitats. The resulting regression equation for FMR explained over 99% of the variation and corresponded to the function FMR (kilojoules per day)=1079 (kilograms of BW0.668) (n=5, r2=0.995, P<0.001). The FMR measured in this study, the first reported for a South American camelid species, suggests that free‐ranging alpacas have similar energy expenditures on a metabolic weight basis as other wild ruminants living under harsh climatic conditions. J. Exp. Zool. 307A:667–675, 2007. © 2007 Wiley‐Liss, Inc.
Temperature‐induced gene expression associated with different thermal reaction norms for growth rate
Authors: Ellers Jacintha , Mariën Janine , Driessen Gerard , van Straalen Nico M.
Published: September 2007

Although nearly all organisms are subject to fluctuating temperature regimes in their natural habitat, little is known about the genetics underlying the response to thermal conditions, and even less about the genetic differences that cause individual variation in thermal response. Here, we aim to elucidate possible pathways involved in temperature‐induced phenotypic plasticity of growth rate. Our model organism is the collembolanOrchesella cinctathat occurs in a wide variety of habitats and is known to be adapted to local thermal conditions. Because sequence information is lacking inO. cincta, we constructed cDNA libraries enriched for temperature‐responsive genes using suppression subtractive hybridization. We compared gene expression ofO. cinctawith steep thermal reaction norms (high plasticity) to those with flat thermal reaction norms (low plasticity) for juvenile growth after exposure to a temperature switch composed of a cooling or a warming treatment. Using suppression subtractive hybridization, we found differential expression of ten nuclear genes, including several genes involved in energy metabolism, such as pantothenate kinase and carbonic anhydrase. In addition, seven mitochondrial genes were found in the cloned subtracted library, but further analysis showed this was caused by allelic variation in mitochondrial genes in our founder population, and that a specific haplotype was associated with high thermal responsiveness. Future work will focus on candidate genes from pathways such as the oxidative phosphorylation and biosynthesis of coenzyme A which are possibly involved in thermal responsiveness of juvenile growth rate.J. Exp. Zool. (Mol. Dev. Evol.) 310B:137–147, 2008. © 2007 Wiley‐Liss, Inc.
Oogenesis in four species of Piscicola (Hirudinea, Rhynchobdellida)
Authors: Spałek‐Wołczyńska Aleksandra , Klag Jerzy , Bielecki Aleksander , Świątek Piotr
Published: September 2007

Piscicola has a pair of elongated sac‐shaped ovaries. Inside the ovaries are numerous small somatic cells and regularly spherical egg follicles. Each follicle is composed of three types of cells: many (average 30) germ cells (cystocytes) interconnected by intercellular bridges in clones (cysts), one intermediate cell, and three to five outer follicle cells (envelope cells). Each germ cell in a clone has one intercellular bridge connecting it to the central anucleate cytoplasmic mass, the cytophore. Each cluster of germ cells is completely embedded inside a single huge somatic follicle cell, the intermediate (interstitial) cell. The most spectacular feature of the intermediate cell is its development of a system of intracytoplasmic canals apparently formed of invaginations of its cell membrane. Initially the complex of germ cell cluster + intermediate cell is enclosed within an envelope composed of squamous cells. As oogenesis progresses the envelope cells gradually degenerate. All the germ cells that have terminated their mitotic divisions are of similar size and enter meiotic prophase, but one of the cystocytes promptly starts to grow faster and differentiates into the oocyte, whereas the remaining cystocytes withdraw from meiosis and become nurse cells (trophocytes). Numerous mitochondria, ER, and a vast amount of ribosomes are transferred from the trophocytes via the cytophore toward the oocyte. Eventually the oocyte ingests all the content of the cytophore, and the trophocytes degenerate. Little vitellogenesis takes place; the oocyte gathers nutrients in the form of small lipid droplets. At the end of oogenesis, an electron‐dense fibrous vitelline envelope appears around the oocyte, among short microvilli. At the same time, electron‐dense cortical granules occur in the oocyte cortical cytoplasm; at the end of oogenesis they are numerous, but after fertilization they disappear from the ooplasm. In the present article we point out many differences in the course of oogenesis in two related families of rhynchobdellids: piscicolids and glossiphoniids. J. Morphol., 2008. © 2007 Wiley‐Liss, Inc.
Ultrastructure of the digestive tract in Acarus siro (Acari: Acaridida)
Authors: Šobotník Jan , Alberti Gerd , Weyda František , Hubert Jan
Published: September 2007

The gut of the mite Acarus siro is characterized on the ultrastructural level. It consists of the foregut (pharynx, esophagus), midgut (ventriculus, caeca, colon, intercolon, postcolonic diverticula, postcolon), and hindgut (anal atrium). The gut wall is formed by a single‐layered epithelium; only regenerative cells are located basally and these have no contact with the lumen. Eight cell types form the whole gut: (i) simple epithelial cells forming fore‐ and hindgut; (ii) cells that probably produce the peritrophic membrane; (iii) regenerative cells occurring in the ventriculus, caeca, colon, and intercolon; (iv) spherite cells and (v) digestive cells forming the ventriculus and caeca; (vi) colonic cells and (vii) intercolonic cells; and (viii) cells forming the walls of postcolonic diverticula and postcolon. Spherite and digestive cells change in structure during secretory cycles, which are described and discussed. The cycle of spherite, colonic, and intercolonic cells is terminated by apoptosis. Ingested food is packed into a food bolus surrounded by a single homogeneous peritrophic membrane formed by addition of lamellae that subsequently fuse together. The postcolonic diverticula serve as a shelter for filamentous bacteria, which also are abundant in the intercolon. J. Morphol., 2008. © 2007 Wiley‐Liss, Inc.
Cell dynamic adhesion and elastic properties probed with cylindrical atomic force microscopy cantilever tips
Authors: Rico Félix , Roca‐Cusachs Pere , Sunyer Raimon , Farré Ramon , Navajas Daniel
Published: September 2007

Cell adhesion is required for essential biological functions such as migration, tissue formation and wound healing, and it is mediated by individual molecules that bind specifically to ligands on other cells or on the extracellular matrix. Atomic force microscopy (AFM) has been successfully used to measure cell adhesion at both single molecule and whole cell levels. However, the measurement of inherent cell adhesion properties requires a constant cell–probe contact area during indentation, a requirement which is not fulfilled in common pyramidal or spherical AFM tips. We developed a procedure using focused ion beam (FIB) technology by which we modified silicon pyramidal AFM cantilever tips to obtain flat‐ended cylindrical tips with a constant and known area of contact. The tips were validated on elastic gels and living cells. Cylindrical tips showed a fairly linear force–indentation behaviour on both gels and cells for indentations >200 nm. Cylindrical tips coated with ligands were used to quantify inherent dynamic cell adhesion and elastic properties. Force, work of adhesion and elasticity showed a marked dynamic response. In contrast, the deformation applied to the cells before rupture was fairly constant within the probed dynamic range. Taken together, these results suggest that the dynamic adhesion strength is counterbalanced by the dynamic elastic response to keep a constant cell deformation regardless of the applied pulling rate. Copyright © 2007 John Wiley & Sons, Ltd.
Probing the interaction forces between hydrophobic peptides and supported lipid bilayers using AFM
Authors: Andre Guillaume , Brasseur Robert , Dufrêne Yves F.
Published: September 2007

Despite the vast body of literature that has accumulated on tilted peptides in the past decade, direct information on the forces that drive their interaction with lipid membranes is lacking. Here, we attempted to use atomic force microscopy (AFM) to explore the interaction forces between the Simian immunodeficiency virus peptide and phase‐separated supported bilayers composed of various lipids, i.e. dipalmitoylphosphatidylcholine, dioleoylphosphatidylcholine, dioleoylphosphatidic acid and dipalmitoylphosphatidylethanolamine. Histidine‐tagged peptides were attached onto AFM tips terminated with nitrilotriacetate and tri(ethylene glycol) groups, an approach expected to ensure optimal exposure of the C‐terminal hydrophobic domain. Force–distance curves recorded between peptide‐tips and the different bilayer domains always showed a long‐range repulsion upon approach and a lack of adhesion upon retraction, in marked contrast with the hydrophobic nature of the peptide. To explain this unexpected behaviour, we suggest a mechanism in which lipids are pulled out from the bilayer due to strong interactions with the peptide‐tip, in agreement with the very low force needed to extract lipids from supported bilayers. Copyright © 2007 John Wiley & Sons, Ltd.
Fast detection of quadruplex structure in DNA by the intrinsic fluorescence of a single‐stranded DNA binding protein
Authors: Zhuang Xin‐ying , Tang Jun , Hao Yu‐hua , Tan Zheng
Published: September 2007

Single‐stranded guanine‐rich (G‐rich) DNA can fold into a four‐stranded G‐quadruplex structure and such structures are implicated in important biological processes and therapeutic applications. So far, bioinformatic analysis has identified up to several hundred thousand of putative quadruplex sequences in the genome of human and other animal. Given such a large number of sequences, a fast assay would be desired to experimentally verify the structure of these sequences. Here we describe a method that identifies the quadruplex structure by a single‐stranded DNA binding protein from a thermoautotrophic archaeon. This protein binds single‐stranded DNA in the unfolded, but not in the folded form. Upon binding to DNA, its fluorescence can be quenched by up to 70%. Formation of quadruplex greatly reduces fluorescence quenching in a K+‐dependent manner. This structure‐dependent quenching provides simple and fast detection of quadruplex in DNA at low concentration without DNA labelling. Copyright © 2007 John Wiley & Sons, Ltd.
Quality of plant products from organic agriculture
Authors: Rembiałkowska Ewa
Published: September 2007

During the last decade, consumers' trust in food quality has decreased drastically, mainly because of growing ecological awareness and several food scandals (e.g. BSE, dioxins, bacterial contamination). It has been found that intensive conventional agriculture can introduce contaminants into the food chain. Consumers have started to look for safer and better controlled foods produced in more environmentally friendly, authentic and local systems. Organically produced foods are widely believed to satisfy the above demands, leading to lower environmental impacts and higher nutritive values. So far, studies have partly confirmed this opinion. Organic crops contain fewer nitrates, nitrites and pesticide residues but, as a rule, more dry matter, vitamin C, phenolic compounds, essential amino acids and total sugars than conventional crops. Organic crops also contain statistically more mineral compounds and usually have better sensory and long‐term storage qualities. However, there are also some negatives: plants cultivated in organic systems generally have 20% lower yields than conventionally produced crops. Several important problems need to be addressed in the coming years: environmental, bacterial and fungal contamination of organic crops and, the most essential issue, the impact of organic food consumption on animal and human health. Copyright © 2007 Society of Chemical Industry
Furanocoumarins in vegetables: influence of farming system and other factors on levels of toxicants
Authors: Schulzová Věra , Hajšlová Jana , Botek Petr , Peroutka Radek
Published: September 2007

Furanocoumarins are toxic chemicals that occur naturally in edible food plants such as celery, parsnip, carrot, etc. belonging to the Apiaceae family. Lower levels of these phytochemicals are also found in citrus fruits and other crops representing the Rutaceae family. Since their presence in the human diet represents a food safety issue of concern, more knowledge is needed to reduce consumer exposure. This paper provides an overview of various factors influencing the levels of furanocoumarins in vegetables and processed commodities. Special attention is paid to the comparison of crops from organic and conventional farming systems with regard to levels of furanocoumarins and their changes during storage and processing. Copyright © 2007 Society of Chemical Industry
A numerical study of a semi‐algebraic multilevel preconditioner for the local discontinuous Galerkin method
Authors: Castillo Paul E. , Velázquez Esov S.
Published: September 2007

In this work, we consider the local discontinuous Galerkin (LDG) method applied to second‐order elliptic problems arising in the modeling of single‐phase flows in porous media. It has been recently proven that the spectral condition number of the stiffness matrix exhibits an asymptotic behavior of 𝒪(h−2) on structured and unstructured meshes, where h is the mesh size. Thus, efficient preconditioners are mandatory. We present a semi‐algebraic multilevel preconditioner for the LDG method using local Lagrange‐type interpolatory basis functions. We show, numerically, that its performance does not degrade, or at least the number of iterations increases very slowly, as the number of unknowns augments. The preconditioner is tested on problems with high jumps in the
coefficients, which is the typical scenario of problems arising in porous media. Copyright © 2007 John Wiley & Sons, Ltd.
Lagrangian finite element treatment of transient vibration/acoustics of biosolids immersed in fluids
Authors: Krysl P. , Cranford T. W. , Hildebrand J. A.
Published: September 2007

Superposition principle is used to separate the incident acoustic wave from the scattered and radiated waves in a displacement‐based finite element model. An absorbing boundary condition is applied to the perturbation part of the displacement. Linear constitutive equation allows for inhomogeneous, anisotropic materials, both fluids and solids. Displacement‐based finite elements are used for all materials in the computational volume. Robust performance for materials with limited compressibility is achieved using assumed‐strain nodally integrated simplex elements or incompatible‐mode brick elements. A centered‐difference time‐stepping algorithm is formulated to handle general damping accurately and efficiently. Verification problems (response of empty steel cylinder immersed in water to a step plane wave, and scattering of harmonic plane waves from an elastic sphere) are discussed for assumed‐strain simplex and for voxel‐based brick finite element models. A voxel‐based modeling scheme for complex biological geometries is described, and two illustrative results are presented from the bioacoustics application domain: reception of sound by the human ear and simulation of biosonar in beaked whales. Copyright © 2007 John Wiley & Sons, Ltd.
Systematic search for the best gene expression markers for melanoma micrometastasis detection
Authors: Soikkeli J , Lukk M , Nummela P , Virolainen S , Jahkola T , Katainen R , Harju L , Ukkonen E , Saksela O , Hölttä E
Published: September 2007

Melanoma is notorious for its high tendency to metastasize and its refractoriness to treatment thereafter. Metastasis is believed to occur mostly through the lymphatic system, and the status of sentinel lymph nodes is currently recognized as the best prognostic indicator. Unfortunately, the lymphatic metastatic process is still poorly understood and the occurrence of sentinel node metastases (micrometastases) may be underestimated. We performed genome‐wide gene expression analyses of melanoma lymph node micrometastases and macrometastases, and of primary melanomas and benign naevi, to characterize the early metastatic cells molecularly and to disclose the best diagnostic markers and rational targets for therapy. Significance analysis of microarrays identified 22 over‐ and five under‐expressed genes with ≥ four‐fold changes in the micrometastases. Of these genes, MLANA, TYR, MIA, ERBB3, PRAME, and SPP1 were tested as potential markers by RT‐PCR and immunohistochemistry. In a prospective study of 160 patients, our graded MLANA and TYR RT‐PCR analyses disclosed clinically significant metastases, as assessed by disease recurrence, better than histological and immunohistochemical examinations. These results strongly suggest the clinical implementation of quantifiable RT‐PCR assays to confirm and complement the pathological examination of sentinel node metastases. Furthermore, SPP1 and PRAME proved valuable as melanoma‐specific markers capable of differentiating melanoma cells from benign naevi in the sentinel lymph nodes. Importantly, these two genes may also prove to be ideal targets for drug development and therapy. Most molecular traits of the micrometastases were already present in the primary tumours, suggesting that micrometastasis to sentinel lymph nodes is a fairly non‐selective process. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Glomerular barrier dysfunction in glomerulosclerosis‐resistant Milan rats with experimental diabetes: the role of renal haemodyamics (J Pathol 2007; 213: 210–218)
Authors: Pugliese G , Ricci C , Iacobini C , Menini S , Fioretto P , Ferrandi M , Giardino LA , Armelloni S , Mattinzoli D , Rastaldi MP , Pugliese F
Published: September 2007

The original article to which this Erratum refers was published in The Journal of Pathology 2007; 213: 210–218
Fractionation of ethylene/1‐pentene copolymers using a combination of SEC‐FTIR and SEC‐HPer DSC
Authors: Luruli Nyambeni , Pijpers Thijs , Brüll Robert , Grumel Valérie , Pasch Harald , Mathot Vincent
Published: September 2007

The short chain branching distribution (SCBD) and thermal properties of ethylene/1‐pentene copolymers were studied using SEC‐FTIR and SEC‐HPer DSC. The copolymers, synthesized with Cp2ZrCl2/MAO, were fractionated using size exclusion chromatography (SEC). The infrared analysis of the fractions showed that the copolymers had—on average—higher 1‐pentene concentration in the low molecular weight range. Furthermore, the thermal properties of the SEC deposits of these copolymers on a Germanium disc were studied using high performance differential scanning calorimetry (HPer DSC). Single SEC separations were used to accumulate fractions in the microgram range that were directly analyzed with regard to their thermal properties, thus allowing us to study SCBD as well as thermal behavior simultaneously. When these fractions (with masses ranging from 10–80 μg) were analyzed using HPer DSC, good melting and crystallization temperature distributions were obtained, proving that HPer DSC can be used as a complementary method to SEC‐FTIR. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 2956–2965, 2007
Crystallization and phase morphology of injection‐molded isotactic polypropylene (iPP)/syndiotactic polypropylene (sPP) blends
Authors: Zou Xiao‐Xuan , Yang Wei , Zheng Guo‐Qiang , Xie Bang‐Hu , Yang Ming‐Bo
Published: September 2007

The crystallization and phase morphology of the injection‐molded isotactic polypropylene (iPP)/syndiotactic polypylenen (sPP) blends were studied, focusing on the difference between the skin layer and core layer. The distribution of crystallinity of PPs in the blends calculated based upon the DSC results shows an adverse situation when compared with that in the neat polymer samples. For 50/50 wt % iPP/sPP blend, the SEM results indicated that a dispersed structure in the skin layer and a cocontinuous structure in the core layer were observed. A migration phenomenon that the sPP component with lower crystallization temperature and viscosity move to the core layer, whereas the iPP component with higher crystallization temperature and viscosity move to the skin layer, occurred in the iPP/sPP blend during injection molding process. The phenomenon of low viscosity content migrate to the low shear zone may be due to the crystallization‐induced demixing based upon the significant difference of crystallization temperature in the sPP and iPP. This migration caused the composition inhomogeneity in the blend and influenced the accuracy of crystallinity calculated based upon the initial composition. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 2948–2955, 2007
A monitoring study to assess the acute mortality effects of indoxacarb on honey bees (Apis mellifera L.) in flowering apple orchards
Authors: van der Steen Jozef JM , Dinter Axel
Published: September 2007

To evaluate the effect of the indoxacarb 300 g kg−1 WG, Steward 30WDG™, on the honey bee (Apis mellifera L.) in apple orchards, a monitoring study was conducted in Dutch apple orchards in April/May 2004. Before apple flowering began, two honey bee colonies were placed in each orchard to investigate honey bee mortality. Each hive was provided with a Münster dead bee trap to collect dead honey bees. The numbers of dead bees found in these Münster dead traps were counted every 3–4 days for about 2 weeks before and after the period of the insecticide treatment. In nine flowering orchards no indoxacarb was applied during the flowering period, which served as control sites. In 30 flowering orchards indoxacarb was sprayed by the fruit growers according to local practice at 170–260 g formulated product ha−1 (51–78 g AI ha−1). In the control orchards the average mortality was 8 honey bees colony−1 day−1. The average daily honey bee mortality before and after indoxacarb application was 8 and 10 honey bees colony−1 day−1 respectively. At one test site, indoxacarb was mixed with other plant protection products plus plant nutrients, and in this orchard a slight but biologically non‐significant increase in acute honey bee mortality was recorded. It was concluded that the application of indoxacarb caused no effects on honey bee mortality, and that the number of dead honey bees counted in the Münster traps in the orchard treated with indoxacarb was comparable with those determined in control orchards. Copyright © 2007 Society of Chemical Industry
A partially structured region of a largely unstructured protein, Plasmodium falciparum merozoite surface protein 2 (MSP2), forms amyloid‐like fibrils
Authors: Yang Xiaodong , Adda Christopher G. , Keizer David W. , Murphy Vince J. , Rizkalla Michael M. , Perugini Matthew A. , Jackson David C. , Anders Robin F. , Norton Raymond S.
Published: September 2007

Merozoite surface protein 2 (MSP2) from the human malaria parasite Plasmodium falciparum is expressed as a GPI‐anchored protein on the merozoite surface. It has been implicated in the process of erythrocyte invasion and is a leading vaccine candidate. MSP2 is an intrinsically unstructured protein (IUP), and recombinant MSP2 forms amyloid‐like fibrils upon storage. We have examined synthetic peptides corresponding to sequences in the conserved N‐terminal region of MSP2 for the presence of local structure and the ability to form fibrils related to those formed by full‐length MSP2. In a 25‐residue peptide corresponding to the entire N‐terminal region of mature MSP2, structures calculated from NMR data show the presence of nascent helical and turn‐like structures. An 8‐residue peptide from the central region of the N‐terminal domain (residues 8–15) also formed a turn‐like structure. Both peptides formed fibrils that were similar but not identical to the amyloid‐like fibrils formed by full‐length MSP2. Notably, the fibrils formed by the peptides bound both Congo Red and Thioflavin T, whereas the fibrils formed by full‐length MSP2 bound only Congo Red. The propensity of peptides from the N‐terminal conserved region of MSP2 to form amyloid‐like fibrils makes it likely that this region contributes to fibril formation by the full‐length protein. Thus, in contrast to the more common pathway of amyloid formation by structured proteins, which proceeds via partially unfolded intermediates that then undergo β‐aggregation, MSP2 is an example of a largely unstructured protein with at least one small structured region that has an important role in fibril formation. Copyright © 2007 European Peptide Society and John Wiley & Sons, Ltd.
Effect of positive charge in VIP 16γ‐glutamyl diamino derivatives on hVPAC1 and hVPAC2 receptor function
Authors: de Maria Salvatore , Metafora Vittoria , Metafora Salvatore , Ravagnan Gianpietro , Cartení Maria , Pontoni Gabriele , Facchiano Angelo , Lepretti Marilena , Severino Beatrice , Caliendo Giuseppe , Santagada Vincenzo , Langer Ingrid , Robberecht Patrick
Published: September 2007

Increase of VPAC receptor s binding to the 16γ‐glutamyl diaminopropane vasoactive intestinal peptide (VIP‐DAP) agonist, a vasoactive intestinal polypeptide (VIP) structural analogue containing a positive charge at position 16, has confirmed the importance of a positive charge at this site. By investigating the effect of distance from the peptide backbone Cα of a positive charge in position 16, data are reported here concerning: (i) a novel chemical method used for the synthesis of a new family of 16γ‐glutamyl diamine VIP derivatives differing among them for single carbon atoms and including diaminoethane (VIP‐DAE2), diaminopropane (VIP‐DAP3), diaminobutane (VIP‐DAB4), diaminopentane (VIP‐DAP5), and diaminohexane (VIP‐DAH6); (ii) functional characterization of these compounds on human VPAC1 and VPAC2 receptors. In more detail, the EC50 and IC50 values, when measured as a function of the alkylic chain length, show in more detail, that the use of VIP‐DAB4 derivative changes the IC50 but not the EC50, thus indicating on hVPAC2 receptor an unexpected relationship between binding and activity that differs from that obtained on hVPAC1. Copyright © 2007 European Peptide Society and John Wiley & Sons, Ltd.
Characterization of monohydroxylated derivatives of the anticancer agent flavone‐8‐acetic acid by liquid chromatography with on‐line UV and mass spectrometry
Authors: Pham Minh Hien , Menet Marie‐Claude , Dugay Annabelle , Regazzetti Anne , Dauzonne Daniel , Auzeil Nicolas , Scherman Daniel , Chabot Guy G.
Published: September 2007

The experimental anticancer agent flavone‐8‐acetic acid (FAA) is metabolized into several monohydroxylated derivatives using mouse microsomes. Because these metabolites could be involved in the biological effects of FAA, the aim of this study was to characterize all its possible monohydroxylated derivatives. To do so, we have developed a methodology using reversed‐phase high‐performance liquid chromatography (RP‐HPLC) coupled with ultraviolet (UV) detection and mass spectrometry (MS) to analyze and identify FAA derivatives hydroxylated at the 2′, 3′, 4′, 3, 5, 6, or 7 position. In RP‐HPLC, 4′‐, 3′‐, 2′‐, 6‐, and 7‐OH‐FAA eluted before FAA, whereas 3‐ and 5‐OH‐FAA eluted after FAA. UV spectra showed a bathochromic shift of band I for all derivatives and of band II for 5‐ and 6‐OH‐FAA. In addition, the position of the OH group could be determined by the presence of certain product ions in MS. Ions atm/z133 and 151 were specific for 2′‐, 3′‐, 4′‐, and 3‐OH‐FAA, whereas the ion atm/z177 was specific for 3‐OH‐FAA only. The ionsm/z133, 151 and 167 were specific for 2′‐OH‐FAA. Ions atm/z149 were specific for the presence of the OH group on cycle A only (i.e., 5‐, 6‐ or 7‐OH‐FAA). The presence of both product ionsm/z149 and 179 were specific for 7‐OH‐FAA. Finally, ions atm/z149 and several product ions of evenm/zvalues were specific for 5‐OH‐FAA. In conclusion, the methodology described can be used to identify all possible monohydroxylated FAA derivatives. Copyright © 2007 John Wiley & Sons, Ltd.
Targeted mass spectrometric strategy for global mapping of ubiquitination on proteins
Authors: Mollah Sahana , Wertz Ingrid E. , Phung Qui , Arnott David , Dixit Vishva M. , Lill Jennie R.
Published: September 2007

Post‐translational modifications of proteins including phosphorylation, glycosylation, acetylation and ubiquitination facilitate the regulation of many cellular processes and intracellular signaling events. Ubiquitination plays a key role in the functional regulation and degradation of many classes of proteins, and the study of ubiquitination and poly‐ubiquitination has emerged as one of the most active areas in proteomic research. A variety of mass spectrometric methods have been described for the identification of ubiquitination sites, the study of poly‐ubiquitin topology and the identification of ubiquitin substrates. The most popular workflow for both ubiquitination site mapping and poly‐ubiquitination chain topology characterization is to take advantage of the Gly‐Gly signature on the substrate's lysine residue observed after tryptic digestion. Although a number of protocols have been described for the mapping of ubiquitination sites, one major challenge is that ubiquitination is typically heterogeneous, and several lysine residues may be ubiquitinated within a protein. When multiple ubiquitination sites are present, multiple analyses are often required to cover all of the potential modification sites which in turn can necessitate the usage of larger quantities of material. In addition, the level of ubiquitination on endogenous and recombinant proteins may be of low intensity, adding further analytical challenges in the identification of this modification. The use of the multiple reaction monitoring (MRM)‐initiated detection and sequencing workflow (MIDAS™) for the identification of phosphorylation sites has previously been described. Here, we explore the use of an MRM workflow for ubiquitination site mapping on the substrate protein, receptor interacting protein (RIP). Copyright © 2007 John Wiley & Sons, Ltd.
Using a Poisson approximation to predict the isotopic distribution of sulphur‐containing peptides in a peptide‐centric proteomic approach
Authors: Valkenborg Dirk , Assam Pryseley , Thomas Grégoire , Krols Luc , Kas Koen , Burzykowski Tomasz
Published: September 2007

Breen et al. (Electrophoresis 2000; 21: 2243) proposed a method for finding monoisotopic peptide peaks in mass spectra based on an approximation of the distribution of different isotopic variants of a peptide by a Poisson distribution. They developed the method using all protein sequences from the SWISS‐PROT database. We investigate the suitability of this method to predict the isotopic distribution in an environment which enriches for peptides carrying sulphur. More specifically, we focus on mass spectra obtained by a COmbined FRActional DIagonal Chromatography (COFRADIC) approach, developed by Gevaert et al. (Nature Biotechnology 2003; 21: 566), targeting a specific subset of peptides, in this case the N‐terminal peptides. One can therefore ask whether the original results of Breen et al. apply to spectra generated by the particular COFRADIC method. We investigate whether the proposed approximation holds for N‐terminal peptides. We also evaluate whether ignoring sulphur atoms while developing the approximation, as proposed by Breen et al., does not increase the risk of missing monoisotopic peaks corresponding to sulphur‐containing peptides. Finally, we check the sensitivity of the quality of the approximation to optimization criteria used in the development process. The results are not simply restricted to a COFRADIC setting but are also applicable more generally, for any method which enriches for sulphur‐containing peptides. Copyright © 2007 John Wiley & Sons, Ltd.
An international study: Effect of farm manure on the release of phosphorus from fly ash
Authors: Urvashi  , Masto R. Ebhin , Selvi V. A. , Ram L. C. , Srivastava N. K.
Published: September 2007

Fly ash is abundantly produced from thermal power plants and is considered a hazardous waste. However, in recent years, fly ash has been widely utilized in the agricultural sector as a soil modifier. It is particularly important for wasteland/mine spoil reclamation due to its ability to provide a source of plant nutrients and improve physicochemical properties of soil. Although fly ash itself contains many plant nutrients, most nutrients, including phosphorus (P), are in a bound form not easily available to plants. This study analyzed the effect of farm manure on the solubility of P from fly ash. Incubation studies were conducted to determine the effect of farm manure on P solubilization to use as a potential option for remediation. © 2007 Wiley Periodicals, Inc.
Formerly utilized sites remedial action program “completed” sites: Lessons for long‐term stewardship
Authors: Abbotts John , Takaro Tim K. , Weems Charles
Published: September 2007

The Formerly Utilized Sites Remedial Action Program (FUSRAP) covers inactive commercial, federal, and university facilities that once supported activities of the Manhattan Project or Atomic Energy Commission. Current responsibilities, established by a Memorandum of Understanding (MOU), are split between the U.S. Department of Energy (US DOE) and the U.S. Army Corps of Engineers. The MOU distinguishes between facilities remediated before 1997 (“completed” sites) and those where remediation remained to be completed at that time. This article evaluates activities conducted at completed sites with regard to considerations for long‐term stewardship, which is defined by the US DOE as all activities necessary to protect human health and the environment after remediation is considered complete. Experience with these FUSRAP sites provides “lessons learned” for the requirements of satisfactory long‐term stewardship. © 2007 Wiley Periodicals, Inc.
Fatigue life investigation of solid and hollow rollers under pure normal loading
Authors: Abu‐Jadayil W.M. , Flugrad D.R.
Published: September 2007

Two solid and hollow cylindrical rollers in pure rolling contact subjected to pure normal loading have been modelled. Using a finite element package called ABAQUS, the stress and strain distributions in the two rollers in contact have been determined. The relative fatigue life of the hollow rollers compared to solid rollers has been investigated using the fatigue life model for rolling bearings developed by Ioannides and Harris. Different hollowness percentages have been studied: 20, 40, 60 and 80%. The hollowness percentage is the ratio of the diameter of the hole to the outer diameter of the cylinder. Both cases were studied – when the two rollers in contact are hollow and when only one of them is hollow while the other one is solid. Making the rollers hollow will result in redistribution of stresses over a larger volume in the contact zone due to the flexibility of the hollow rollers. That decreases the peak stress in the contact zone of the hollow cylinder when compared to the solid cylinder. Hollow cylinders have more flexibility when subjected to normal loading. And so, the stresses are redistributed so that the fatigue life is improved. The best stress redistribution and so fatigue life improvements have been found when both cylinders have around 60% hollowness. Copyright © 2007 John Wiley & Sons, Ltd.
Particle movement patterns and their prediction in abrasive flow machining
Authors: Fang Liang , Sun Kun , Cen Qihong
Published: September 2007

Abrasive particle movement pattern is an important factor in estimating the wear rate of materials, especially, as it is closely related to the burring, buffing and polishing efficiency of the abrasive flow machining (AFM) process. There are generally two kinds of particle movement patterns in the AFM process, i.e. sliding–rubbing and rolling. In mechanism, AFM grain–workpiece interaction is taking place in any one or a combination of the possible modes: elastic/plastic deformation by sliding–rubbing grain movement; elastic/plastic deformation by rolling grain movement; chip formation (micro‐cutting) by rubbing grain movement; ridges formation by rubbing and rolling grain movement; and low‐cycle fatigue wear. Therefore, the machining efficiency of a machine part is predominantly dependent upon the particle movement patterns. In this paper, normal load, particle size and hardness of machine parts were investigated to understand the involved parameters of particle movement patterns and propose a computer statistic prediction of particle movement patterns. It has been found that there are two cases. In case of large‐size particles, the ratio of rolling particles is increased with increasing normal load. For small‐size particles, the ratio of grooving particles is increased with increasing normal load and vice versa. When normal load is light, the particle size cannot usually give an effect on movement patterns. That influence will be predominant under heavy normal load. Most of the particles will tend to groove when the particle size is below a certain value. Hardness of the material and their hardness difference for tribological pairs are other important monitors in predicting particle movement patterns. In this research, increasing hardness of materials results in more rolling particles, which results in much less cutting particles. Copyright © 2007 John Wiley & Sons, Ltd.
Spatial organization and spatial distribution of activities within home ranges in a Springbok (Antidorcas marsupialis) captive population
Authors: Mechkour Farah , Maublanc Marie‐Line , Bideau Eric , Gerard Jean‐François , Pépin Dominique
Published: September 2007

We studied over 1 year the spatial organization and the spatial distribution of activities in a captive springbok (Antidorcas marsupialis) population living in an 18‐ha enclosure located in southern France. Throughout the study period, the two adult males occupied fairly exclusive home ranges, in the overlapping part of which the three subadult males were restricted. The spatial and temporal distribution of aggressive, marking, and avoidance behavior of males showed that the two adults were territorial, except during summer. They accounted for 71% of all marking behaviors recorded, for 77% of the aggressive behavior, and for 91% of the sexual interactions, whereas subadult males accounted for 94% of the avoidance behavior observed. The adult females used the whole enclosure, moving through the males' home ranges. They fed everywhere, but they all had the same preferred resting area, located in the center of the territory of one of the two adult males. They gave birth, accounted for maternal behavior and were engaged in sexual interactions in sectors differing from one individual to the other, but mainly outside the sector where all males' home ranges overlapped. Our results are compared to those reported in natural conditions and lead us to discuss both the functional interpretations of marking behavior, and the signification of a home range for an ungulate. Zoo Biol 27:19–35, 2008. © 2007 Wiley‐Liss, Inc.
Saturated and Unsaturated Wax Esters Produced by Acinetobacter sp. HO1‐N Grown on C16‐C20n‐Alkanes
Authors: Dewitt S. , Ervin J. L. , Howes‐Orchison D. , Dalietos D. , Neidleman S. L. , Geigert J.
Published: September 2007

The wax ester compositions produced by the action of Acinetobacter sp. HO1‐N on n‐alkanes (C16 through C20) were analyzed using capillary gas chromatography/mass spectrometry (GC/MS). The wax esters contained, surprisingly, a large percentage of mono‐and diunsaturated components. The acyl and alkoxy segments are reported for each wax ester component. Also, the positions of the carbon‐carbon double bonds in the wax esters produced from the C16 and C20 n‐alkanes are reported. These microbial‐produced wax ester mixtures bear a close chemical similarity to those of sperm whale and jojoba oils.
Kinetics of Bleaching of Vegetable Oils
Authors: Brimberg U. I.
Published: September 2007

It was shown in a recent paper that the concentration c of remaining chlorophyll or carotene in rapeseed oil during the bleaching process follows a rate formula, log c/co =– k √t, characteristic of flocculation of colloids. Thus, the pigments are particulate and colloidally dispersed in the oil. The rate constant k was proportional to the added amount of clay. This paper reports experiments with palm oil. The same kinetics as those with rapeseed are valid. The effects of various parameters on the rate have been studied. The mechanism of the process is discussed.
Characteristics of Laboratory‐Processed: Cucurbita foetidissima Seed Oil
Authors: Vasconcellos J. A. , Berry J. W.
Published: September 2007

The effects of variations in laboratory processing on the quality of the seed oil of the buffalo gourd, Cucurbita foetidissima, were determined. Conditions found most effective were: triple refining at 65 C for 15 min using 16°Be and 20°Be NaOH at 80% of maximum and 20°Be NaOH at the maximum; bleaching at 105 C for 30 min by a mixture of activated bleaching earth (3%) and activated carbon (0.3%); and deodorization with 5% steam at 210 C for 120 min. Processed oil showed these analytical values: carotenoids (3.6 mg/kg), free fatty acids (0.28%), peroxide (0.2 meq/kg), conjugated unsaturated fatty acids (1.59%). Oxidative stability test (AOM) conditions gave peroxide values of 100 in 4.9 hr and 141 in 8 hr. The triglyceride fatty acid composition was 11.9% palmitic, 3.5% stearic, 22.0% oleic and 61.0% linoleic acid.
The effect of glycols on the hydrophile‐lipophile balance and the micelle formation of nonionic surfactants
Authors: Marszall Leszek , Van Valkenburg J. Wade
Published: September 2007

The empirical hydrophile‐liophile balance (HLB) value of nonionic surfactants is an important parameter used to predict performance as, e.g., emulsifiers, solubilizers and wetting agents. However, the HLB value is based on an original molecular structure and does not take into account all the factors affecting the performance of nonionics, such as presence of additives, type of solvent, temperature, degree of hydration, structural modifications of the surfactant molecule and decomposition of surfactants. On a performance basis, where these factors come into play, a given nonionic surfactant may exhibit a multiplicity of apparent HLB values. Accordingly, we recently introduced the term “effective HLB value” which is a performance value which incorporates into the HLB the parameters listed above. The HLB value thus becomes a variable depending on the physical and chemical conditions at the time of the measurement. In this work, we investigated the effect of adding glycols and diglycols on the HLB using 3 different methods: cloud point, phenol index and critical micelle concentration (cmc). We found that this type of additive increases the cloud point, phenol index, cmc and the “effective HLB” of a polyoxyethylated nonionic surfactant. The effectiveness of the glycols in causing these increases was in the following order; dipropylene glycol > 1,4‐butanediol > 1,2‐propanediol > diethylene glycol > ethylene glycol. The solvent effect of glycols and diglycols on the hydrophobic and hydrophilic portions of the surfactant molecule are discussed. On the hydrocarbon part of the surfactant molecule, the solvents cause a weakening of the hydrophobic bond and an increase in the cmc. On the polyoxyethylene part of the molecule, the solvent may cause either an increase or a decrease in the cmc. The effect on the hydro‐philic portion is related to hydrogen bonding exhibited by the additives. The results obtained again suggest that the effective HLB value, which is a measure of the HLB under operative conditions, may be of greater practical significance than calculated HLB.