bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ageing and the brain
Authors: Esiri MM 
Published: January 2007

AbstractIn this review, the evidence for changes in the human brain with ageing at both the macroscopic and microscopic levels is summarized. Loss of neurons is now recognized to be more modest than initial studies suggested and only affects some neuron populations. Accompanying loss of neurons is some reduction in the size of remaining neurons. This reflects a reduced size of dendritic and axonal arborizations. Some of the likely causes of these changes, including free radical damage resulting from a high rate of oxidative metabolism in neurons, glycation and dysregulation of intracellular calcium homeostasis, are discussed. The roles of genes and environmental factors in causing and responding to ageing changes are explored. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Hallmarks of telomeres in ageing research
Authors: Shay JW , Wright WE 
Published: January 2007

AbstractTelomeres are repetitive DNA sequences at the ends of linear chromosomes. Telomerase, a cellular reverse transcriptase, helps maintain telomere length in human stem cells, reproductive cells and cancer cells by adding TTAGGG repeats onto the telomeres. However, most normal human cells do not express telomerase and thus each time a cell divides some telomeric sequences are lost. When telomeres in a subset of cells become short (unprotected), cells enter an irreversible growth arrest state called replicative senescence. Cells in senescence produce a different constellation of proteins compared to normal quiescent cells. This may lead to a change in the homeostatic environment in a tissue‐specific manner. In most instances cells become senescent before they can become cancerous; thus, the initial growth arrest induced by short telomeres may be thought of as a potent anti‐cancer protection mechanism. When cells can be adequately cultured until they reach telomere‐based replicative senescence, introduction of the telomerase catalytic protein component (hTERT) into telomerase‐silent cells is sufficient to restore telomerase activity and extend cellular lifespan. Cells with introduced telomerase are not cancer cells, since they have not accumulated the other changes needed to become cancerous. This indicates that telomerase‐induced telomere length manipulations may have utility for tissue engineering and for dissecting the molecular mechanisms underlying genetic diseases, including cancer. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Ageing and hearing loss
Authors: Liu XZ , Yan D 
Published: January 2007

AbstractAlthough many adults retain good hearing as they age, hearing loss associated with ageing is common among elderly persons. There are a number of pathophysiolological processes underlying age‐related changes to functional components in the inner ear. Genetic factors determine the ageing process but are under the influence of intrinsic and environmental factors. It is difficult to distinguish changes of normal ageing from those of other contributing factors. The effects of age‐related deafness can have significant physical, functional and mental health consequences. Although a deficit in hearing can be corrected to some degree by a hearing aid or other appropriate amplification devices, hearing‐related rehabilitative needs are much more than simply amplifying external sound. Only by better understanding the process of ageing and its effect on the auditory function can we better accommodate elderly people in our day‐to‐day interactions. We review here the structure and function of the inner ear, pathophysiology associated with age‐related hearing loss (ARHL), heritability, allelism and modifier genes of ARHL, and evaluate the genetic analyses for identification of genetic factors that are involved. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Renal ageing
Authors: Martin JE , Sheaff MT 
Published: January 2007

AbstractThe function of the kidney, as well as its morphology, changes markedly with age. The glomerular filtration rate falls progressively, independent of overt pathology. Glomerular, vascular and accompanying parenchymal changes occur and other disorders associated with ageing, such as diabetes and hypertension, have a stochastic deleterious effect on both form and function. Declining renal function with age has important implications, not only for individual homeostasis but also for the use of drug therapy and for the receipt and donation of organs for transplantation. Molecular mechanisms and cellular changes underlying some of the functional and structural changes associated with ageing are becoming clearer, as are some of the ways in which genetic background, age and disease can combine to produce functional damage. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
The pathology of ageing: concepts and mechanisms
Authors: Martin JE , Sheaff MT 
Published: January 2007

AbstractThe rising numbers and proportion of aged individuals in the population is a global demographic trend. The diseases associated with ageing are becoming more prevalent, and the associated healthcare costs are having a significant economic impact in all countries. With these changes have come great advances in our understanding of the mechanisms of ageing. The mechanisms of cellular ageing at a genetic, protein and organelle level are becoming clearer, as are some of the more complex associations between environment and ageing. System ageing is also becoming better understood, and the potential biological advantages of ageing are being explored. Many of the advances in these fields are opening up the prospect of targeted therapeutic intervention for ageing and age related disease. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Pulsed Streamer Discharge Plasma over Ni/HZSM‐5 Catalysts for Methane Conversion to Aromatics at Atmospheric Pressure
Authors: Li Xiao‐Song , Shi Chuan , Xu Yong , Zhang Xiu‐Ling , Wang Kang‐Jun , Zhu Ai‐Min 
Published: January 2007

AbstractA novel process consisting of a pulsed streamer discharge over Ni/HZSM‐5 catalysts for an oxygen‐free conversion of methane to aromatics is reported here. This plasma‐over‐catalyst process shows a significant synergetic effect on promoting methane conversion to aromatic products and high stability. Using this process at atmospheric pressure and a temperature of 573 K, significant amounts of aromatics have been obtained.magnified image
Overview of on‐farm bioremediation systems to reduce the occurrence of point source contamination
Authors: De Wilde Tineke , Spanoghe Pieter , Debaer Christof , Ryckeboer Jaak , Springael Dirk , Jaeken Peter 
Published: January 2007

AbstractContamination of ground and surface water puts pressure on the use of pesticides. Pesticide contamination of water can often be linked to point sources rather than to diffuse sources. Examples of such point sources are areas on farms where pesticides are handled and filled into sprayers, and where sprayers are cleaned. To reduce contamination from these point sources, different kinds of bioremediation system are being researched in various member states of the EU. Bioremediation is the use of living organisms, primarily microorganisms, to degrade the environmental contaminants into less toxic forms. The systems available for biocleaning of pesticides vary according to their shape and design. Up till now, three systems have been extensively described and reported: the biobed, the Phytobac® and the biofilter. Most of these constructions are excavations or different sizes of container filled with biological material. Typical overall clean‐up efficiency exceeds 95%, realising even more than 99% in many cases. This paper provides an overview of the state of the art of these bioremediation systems and discusses their construction, efficiency and drawbacks. Copyright © 2007 Society of Chemical Industry
Effect of insulin and its combination with resveratrol or curcumin in attenuation of diabetic neuropathic pain: participation of nitric oxide and TNF‐alpha
Authors: Sharma Sameer , Chopra Kanwaljit , Kulkarni Shrinivas K. 
Published: January 2007

AbstractDiabetic neuropathic pain, an important microvascular complication in diabetes mellitus, is recognized as one of the most difficult types of pain to treat. The underlying mechanisms of painful symptoms may be closely associated with hyperglycaemia but a lack of the understanding of its proper aetiology, inadequate relief, development of tolerance and potential toxicity of classical antinociceptives warrant the investigation of newer agents to relieve this pain. The aim of the present study was to explore the antinociceptive effect of insulin and its combinations with resveratrol and curcumin in attenuating diabetic neuropathic pain. The study also aimed to examine the effect of these combinations on tumour necrosis factor‐alpha (TNF‐α) and nitric oxide (NO) levels in streptozotocin (STZ) induced diabetic mice. Four weeks after a single intraperitoneal injection of streptozotocin (200 mg/kg), mice were tested in the tail immersion and hot‐plate assays. Diabetic mice exhibited significant hyperalgesia along with increased plasma glucose and decreased body weights compared with control mice. Chronic treatment with insulin (10 IU/kg/day, s.c.) and its combinations with antioxidants (resveratrol 20 mg/kg or curcumin 60 mg/kg, p.o.) for 4 weeks starting from the 4th week of STZ injection significantly attenuated thermal hyperalgesia and the hot‐plate latencies. There was a significant inhibition of TNF‐α and NO levels when these drugs were given in combination compared with their effects per se. These results indicate an antinociceptive activity of resveratrol and curcumin and point towards the beneficial effect of these combinations with insulin in attenuating diabetic neuropathic pain, possibly through the participation of NO and TNF‐α. Copyright © 2007 John Wiley & Sons, Ltd.
Pharmaceutical and therapeutic Potentials of essential oils and their individual volatile constituents: a review
Authors: Edris Amr E. 
Published: January 2007

AbstractEssential oils and their volatile constituents are used widely to prevent and treat human disease. The possible role and mode of action of these natural products is discussed with regard to the prevention and treatment of cancer, cardiovascular diseases including atherosclerosis and thrombosis, as well as their bioactivity as antibacterial, antiviral, antioxidants and antidiabetic agents. Their application as natural skin penetration enhancers for transdermal drug delivery and the therapeutic properties of essential oils in aroma and massage therapy will also be outlined. Copyright © 2007 John Wiley & Sons, Ltd.
Theoretical study of the reaction of Cr+ with SCO in gas phase
Authors: Dai Guo‐Liang , Fan Kang‐Nian 
Published: January 2007

AbstractTo elucidate the mechanism of reaction M+ + SCO, the reaction of Cr+ + SCO has been investigated using density functional theory (DFT) with the popular hybrid functional, B3LYP, in conjunction with 6‐311+G* basis set on both the sextet and quartet potential energy surfaces (PESs). To obtain an accurate evaluation of the activation barrier and reaction energy, the coupled cluster single‐point calculations using the B3LYP structures is performed. The crossing points (CPs) of the different PESs have been localized with the approach suggested by Yoshizawa and colleagues. The involving potential energy curve‐crossing dramatically affects reaction mechanism. The present results show that the reaction mechanism is insertion‐elimination mechanism both along the CS and CO bond activation branches, but the CS bond activation is much more favorable than the CO bond activation in energy. All theoretical results not only support the existing conclusions inferred from early experiment study, but also complement the pathway and mechanism for this reaction. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2007
Diel and lateral patterns of zooplankton distribution in the St. Lawrence River
Authors: Casper Andrew F. , Thorp James H. 
Published: January 2007

AbstractWhile the four‐dimensional nature of river ecosystems has been recognized for nearly two decades, the role of lateral complexity has rarely been factored into studies of zooplankton ecology. We examined the importance of hydrologic retention areas (slackwaters) near islands and embayments of the St. Lawrence River for densities, fecundity, and diel migration of planktonic microcrustaceans. Densities of cladocera and copepods (nauplii and adult stages of cyclopoids and calanoids) were sampled from surface and deeper layers both at night (2100–0100 h, near the new moon) and during the day (1000–1400 h) for channel (deep‐fast), offshore (shallow‐slower), and inshore (shallow‐stagnant) habitats. Average zooplankton densities increased laterally from the main channel into the slackwaters with the exception of calanoid copepods, which peaked in the intermediate depths and flows of the offshore habitats. Although the ratio of males to females for the calanoid Eurytemora affinis and the cladoceran Bosmina spp. did not differ among habitats, a greater percentage of ovigerous cladoceran females were present in slackwaters than in channel habitats. Densities of microcrustaceans were generally greater during the night than day, suggesting diel vertical migration. By demonstrating both lateral and diel differences in the spatial distribution of riverine zooplankton, we refute the view of large rivers as well‐mixed homogenous systems. To the contrary, the two non‐random patterns that we document imply that there is an abiotic template that at least microcrustacean potamoplankton can exploit. In turn this suggests more research into the ecological significance of the pelagic structure of other large rivers like the St. Lawrence is justified. Copyright © 2007 John Wiley & Sons, Ltd.
Fine Structure, Thermal and Viscoelastic Properties of Starches Separated from Indica Rice Cultivars
Authors: Singh Narpinder , Nakaura Yoshiko , Inouchi Naoyoshi , Nishinari Katsuyoshi 
Published: January 2007

AbstractStarches were separated from indica rice cultivars (PR‐113, Basmati‐370, Basmati‐386, PR‐115, IR‐64, and PR‐103) and evaluated using gel permeation chromatography (GPC), X‐ray diffraction, differential scanning calorimetry (DSC) and dynamic viscoelasticity. Debranching of starch with isoamylase and subsequent fractionation by GPC revealed 9.7–28.3% apparent amylose content, 3.7–5.0% intermediate fraction (mixture of short amylose and long side‐chains of amylopectin), 20.6–26.6% long side‐chains of amylopectin and 45.8–59.4% short side‐chains of amylopectin). IR‐64 starch with the highest crystallinity had the highest gelatinization temperatures and enthalpy, To, Tp, Tc, and ΔHgel being 71.8, 75.9, 82.4°C and 5.1 J/g, respectively, whereas PR‐113 starch with lower crystallinity showed the lowest gelatinization temperatures (To, Tp, Tc, of 60.8, 65.7 and 72.2°C, respectively). Basmati‐386 starch exhibited two endotherms during heating, the first and second endotherm being associated with the melting of crystallites and amylose‐lipid complexes, respectively. To, Tp, Tc and ΔHgel of the second endotherm of Basmati‐386 starch were 99.0, 100.1, 101.1°C and 2.0 J/g, respectively. During cooling, Basmati‐386 also showed an exotherm at a peak temperature of 87°C. PR‐113 starch with the highest amylose content and the lowest content of short side‐chains of amylopectin had the highest peak storage modulus (G′= 1.6×104 Pa). The granules of PR‐113 starch were the least disintegrated after heating. The effects of heating starch suspensions at different temperatures (92°C, 130°C and 170°C) on intrinsic viscosity [η], transmittance and viscoelasticity were also studied to evaluate the extent of breakdown of the molecular structure. The intrinsic viscosity of starch suspensions heated at 92, 130 and 170°C ranged between 103–114, 96–110 and 28–93 mL/g. Transmittance value of starches cooked at 92°C decreased with increase in storage duration. All starches except PR103, cooked at 130°C also showed decrease in transmittance during storage, however, at lower rate. PR103 starch heated at 130°C did not show any change in transmittance up to a storage time of 48 h. The changes in viscoelasticity of starch pastes cooked at different temperatures during cooling and reheating were also evaluated. G′ and G′′ increased with decrease in temperature during cooling cycle. Starches heated at 130°C with apparent amylose content ≤21.2% showed an improvement in G′ and G′′ in comparison to the corresponding starches heated at 92°C, this improvement was observed to be higher in starches with lower amylose content. All starches heated at 170°C had a higher proportion of breakdown in molecular structure as indicated by lower G′ and G′′ than the same starches heated at 130 and 92°C.
Preparation, Structure, Spectral, and Magnetic Properties of Copper(II) Halogenonicotinates: Crystal and Molecular Structure of Tetrakis(μ‐2‐chloronicotinato‐O,O′)‐diaquadicopper(II)
Authors: Moncol Jan , Korabik Maria , Segl'a Peter , Koman Marian , Mikloš Dušan , Jašková Jana , Glowiak Tadeusz , Melník Milan , Mrozinski Jerzy , Sundberg Markku R. 
Published: January 2007

AbstractThe characterization of the complexes [Cu2(2‐Clnic)4(H2O)2] (1), [Cu(2,6‐Cl2nic)2(H2O)2] (2) and [Cu(5‐Brnic)2(H2O)2]n (3) (where 2‐Clnic = 2‐chloronicotinate, 2,6‐Cl2nic = 2,6‐dichloronicotinate or 5‐Brnic = 5‐bromonicotinate) was based on elemental analysis, IR, electronic and EPR spectra, and magnetic susceptibility. Complex 1 was also studied by X‐ray analysis at 298 1a and 80 K 1b. The complex 1 contains a dinuclear Cu‐acetate molecular structure in which the carboxyl groups of the 2‐chloronicotinate ligands act as bridges and water molecules are at apical positions. The stereochemistry about Cu atom at both temperatures is typical for square pyramidal geometry with CuO4O chromophore. The Cu‐Cu distance is 2.6513(8) and 2.6382(6) Å for 1a and 1b, respectively. The Cu atoms are displaced by 0.2069(9) and 0.1973(7) Å, respectively, from the plane containing four oxygen atoms bonded to the Cu atom toward the apical water molecules. Strong and weak hydrogen bonds as well as C–Cl···π interactions in the crystal structure are discussed as well. Both complexes, monomeric [Cu(2,6‐Cl2nic)2(H2O)2] (2) and polymeric [Cu(5‐Brnic)2(H2O)2]n (3), possess octahedral copper(II) stereochemistry with differing tetragonal distortions.
Structural and Optical Characterization of Ytterbium Doped Lutetium Double Phosphates
Authors: Guzik M. , Legendziewicz J. , Szuszkiewicz W. , Walasek A. 
Published: January 2007

AbstractPowder samples of the ternary phosphates A3Lu(PO4)2:Yb3+ (A = Na, Rb) have been synthesised by solid state reactions. The spectroscopic properties of Yb3+ in double phosphate host lattices were investigated using absorption, emission and excitation spectra at 4, 10 and 293 K in the VUV to IR range. The results obtained for both types of phosphates are compared. Together with the fundamental 2F5/2 → 2F7/2 emission in the IR range, a broad band emission with two peaks in the UV region were observed in Yb3+‐activated Na3Lu(PO4)2. The second emission is due to a charge–transfer transition type. The influence of the alkali metal cation site of the host lattice on the luminescence properties was investigated. The tentative energy level scheme of the ground and excited 2FJ (J=7/2, 5/2) levels is described.
Formation of Unusual Complexes from the Reaction of [C(NMe2)3][(CO)4Fe{C(O)NMe2}] with InMe3; Crystal Structures of [C(NMe2)3]3[Fe2(CO)6(μ‐CO){μ‐InFe(CO)4(μ‐O2CNMe2)InFe(CO)4}] and [C(NMe2)3]2[{(CO)4Fe}2In(O2CNMe2)]·THF
Authors: Neumüller Bernhard , Esser Michael , Petz Wolfgang 
Published: January 2007

AbstractThe carbamoyl complex [C(NMe2)3][(CO)4Fe{C(O)NMe2}] (1) reacts with InMe3 under loss of the methyl groups to produce a variety of compounds from which only the anionic cluster complexes [C(NMe2)3]3[Fe2(CO)6(μ‐CO){μ‐InFe(CO)4(μ‐O2CNMe2)InFe(CO)4}] ([CN3]3[2]) and [C(NMe2)3]2[{(CO)4Fe}2In(O2CNMe2)]·THF ([CN3]2[3]·THF) could be crystallized and characterized by X‐ray analyses. The anion [2]3− has a Fe2(CO)9‐like structure and both anions contain the carbaminato ligand either in a bridging or in a chelating function.
Oxidative Pyrrole Exchange and meso Pyrrylation – Unexpected Reactions of Open‐Chain Tetrapyrrolic 2,2′‐Bidipyrrins
Authors: Bröring Martin , Link Stephan , Cordes Meike , Brandt Carsten D. 
Published: January 2007

AbstractA new hydrogen terminated 2,2′‐bidipyrrin ligand was prepared from a bipyrrole dialdehyde and 3,4‐diethylpyrrole by a POCl3 induced condensation and isolated as the nickel(II) chelate. Unexpectedly a side reaction occured when base‐deficient and aerobic conditions were chosen in the metalation step. This side reaction led to a novel pentapyrrolic nickel(II) complex with one externally bound pyrrole ring. Further studies showed that the reactions of 2,2′‐bidipyrrins with 3,4‐diethyl‐ or 2,3,4‐trimethylpyrrole and an oxidant resulted in a stepwise exchange of the terminal pyrrole moieties and, in the former case, the introduction of one additional pyrrole ring into one of the two meso positions of the open‐chain tetrapyrrole.
How Common Are True Aminopyridinato Complexes?
Authors: Deeken Stefan , Motz Günter , Kempe Rhett 
Published: January 2007

AbstractAn overview over the binding situation in transition metal and lanthanide aminopyridinato complexes is given. True aminopyridinato complexes in which we observe a significant longer N‐amido than N‐pyridine bond length are rare and for instance observed for ruthenium. Additional examples of ruthenium aminopyridinato complexes were synthesized and characterized by X‐ray crystal structure analysis.
A Novel Two‐dimensional Coordination Polymer based on Rhombic Tetrameric Subunit Zn4O4 as Building Block
Authors: Tang Yun‐Zhi , Tan Yu‐Hui , Chen Shao‐Hu , Chao Yan‐Wen 
Published: January 2007

AbstractHydrothermal reaction of olsalazine sodium, phenanthroline and Zn(ClO4)2·6H2O in the presence of water and ethanol affords a two‐dimensional coordination polymer [Zn4(OSA)3(Phen)2(H2O)2]n (1) (OSA = olsalazine) which is characterized by single X‐ray determination, IR and UV spectrum. The local coordination around all zinc ions can be best described as a slightly distorted triangle bipyramid. Complex 1 consists of a tetrameric subunit, which is made up of four Zn atoms bridged by four O atoms. Two types of osalazine ligands can be found in the complex according to their different coordination modes of carboxyl groups. Crystal data for 1: $\rm P{\bar 1}$, a = 10.087(7), b = 12.830(9), c = 14.545(11) Å, α =114.598(10)°, β = 92.552(10)°, γ = 108.515(10)°, V = 1588(2) Å3, Z = 2, R1 = 0.0818, wR2 = 0.1855. In comparison with the free ligand, the UV spectrum of 1 in solution (H2O: EtOH = 1:1) shows a small Einstein shift probably due to the formation of coordination polymer and supramoleculer hydrogen‐bonding interactions.