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Remarkable Differences (remarkable + difference)
Selected AbstractsExtraction and isolation of Pistacia lentiscus L. essential oil by supercritical CO2FLAVOUR AND FRAGRANCE JOURNAL, Issue 4 2002Raffaele Congiu Abstract Supercritical CO2 extraction coupled to a fractional separation technique (SFE) was used to isolate essential oil from the leaves and berries of Pistacia lentiscus L. The technique adopted allowed us to separate the volatile oil from waxes. In the case of the leaf essential oil, the yield was 0.45% by weight of the charged material. The chemical composition of the oil, determined by GC,MS analysis, revealed the presence of ,-caryophyllene (31.38%), germacrene D (12.05%) and ,-cadinene (6.48%). Remarkable differences were noticed in the corresponding hydrodistilled oil, composed chiefly by ,-pinene (18.71%), ,-phellandrene (12.83%) and ,-caryophyllene (13.22%). The yield of volatile oil obtained or treating Pistacia lentiscus berries was only 0.2%. ,-myrcene, ,-pinene and ,-phellandrene are the compounds characteristic of the oil obtained with both methods, SFE and hydrodistillation. Copyright © 2002 John Wiley & Sons, Ltd. [source] Explaining the national differences in pressure ulcer prevalence between the Netherlands and Germany , adjusted for personal risk factors and institutional quality indicatorsJOURNAL OF EVALUATION IN CLINICAL PRACTICE, Issue 1 2009Antje Tannen RN MA MPH Abstract Background, Pressure ulcers have a known impact on quality of life as well as on morbidity and mortality of the persons affected. Remarkable differences in pressure ulcer prevalence between the Netherlands and Germany have been found during the last 6 years. This study explores to what extent the individual risk of the population and quality indicators of the institutions can explain the variation in national prevalence. Methods, Data of a binational multi-centred cross-sectional study in 103 hospitals (n = 21 378 patients) and 129 nursing homes (n = 15 579 residents) were analysed using random effects regression models to calculate the differences in national prevalences within the nursing homes and hospitals, adjusted for personal risk for pressure ulcer and quality indicators. Results, The prevalence of pressure ulcers among the at-risk group (Bradenscore ,20) in nursing homes was 30.8% in the Netherlands and 8.3% in Germany [OR: 4.9 (CI 95%: 4.2,5.7)]. In hospitals, the prevalence among the at-risk group was 26.1% in the Netherlands and 21.2% in Germany [OR: 1.3 (CI 95%: 1.2,1.5)]. After adjusting for individual risk factors (age, gender, Bradenscore) as well as for quality structures (use of prevention and treatment protocols, experts groups, information leaflets, nurses training, central pressure ulcer statistics and regular updating of protocols), the chance of developing a pressure ulcer was 6.05 times higher (CI 95%: 4.0,9.2) in a Dutch nursing home than in a German nursing home. Within the hospitals, the OR for Dutch patients was 2.03 (CI 95%: 1.4,3.0). Conclusion, A remarkable national variation exists in pressure ulcer prevalence and nursing practice. Neither the populations vulnerability for pressure ulcers nor pressure ulcer management as measured in this study could explain this national variation. Therefore, other risk factors should be taken into consideration. Additionally, it is possible that quality indicators are implemented in differing ways with varying levels of effectiveness. Therefore, further research is needed to examine prospectively and in more detail the reality of care within facilities in both countries. [source] Sequence shuffle controls morphological consequences in a self-assembling tetrapeptide,JOURNAL OF PEPTIDE SCIENCE, Issue 2 2008K. B. Joshi Abstract Peptide and protein self-assembly is a well-studied phenomenon in chemistry and biology, where nanoscopic building blocks exhibit rapid self-association to reveal supramolecular aggregates of defined structural features. These superstructures are stabilized by hydrophobic interactions, hydrogen bonding and a host of other noncovalent interactions. Thus, amino acid side chains in the primary structure hold importance in dictating secondary structures and preference for particular conformational signatures in peptide aggregates. This report describes contrasting nanoscale morphologies in antamanide-derived synthetic tetrapeptide mutants, which are composed by shuffling only two amino acids: phenylalanine and proline. Remarkable differences in ultrastructures in primary sequence-shuffled tetrapeptides suggest dissimilar aggregational pathways due to context-dependent location of proline and phenylalanine residues with respect to one another. Copyright © 2007 European Peptide Society and John Wiley & Sons, Ltd. [source] Micro-Raman characterizations of Pompei'smortarsJOURNAL OF RAMAN SPECTROSCOPY, Issue 2 2008M. Castriota Abstract The ancient town of Pompei offers a unique opportunity to study in detail many aspects of the every day life during the Roman early imperial age. The application of micro-Raman spectroscopy can be of great help in performing a reasonably rapid comparative analysis of the mortars, quite useful to ascertain the degree of uniformity of the technical recipes among the various building firms and the eventual technical evolution in the time; moreover, the individuation of minerals of specific geographical origins can give useful information about the extension of commercial intercourses. An example of a micro-Raman investigation on building materials is reported in this work, concerning the analysis of the mortars coming from different points of the wall in the ,The House of the Wedding of Hercules'. Remarkable differences between ancient and modern mortars are found, allowing a discrimination that can be useful in the case of historical building which underwent several restoration works. Copyright © 2008 John Wiley & Sons, Ltd. [source] Broad-scale vegetation-environment relationships in Eurasian high-latitude areasJOURNAL OF VEGETATION SCIENCE, Issue 4 2006Risto Virtanen Hultén & Fries (1986); Ignatov & Afonina (1992); Konstantinova et al. (1992); Vitikainen et al. (1997) Abstract Question: How is tundra vegetation related to climatic, soil chemical, geological variables and grazing across a very large section of the Eurasian arctic area? We were particularly interested in broad-scale vegetation-environment relationships and how well do the patterns conform to climate-vegetation schemes. Material and Methods: We sampled vegetation in 1132 plots from 16 sites from different parts of the Eurasian tundra. Clustering and ordination techniques were used for analysing compositional patterns. Vegetation-environment relationships were analysed by fitting of environmental vectors and smooth surfaces onto non-metric multidimensional scaling scattergrams. Results: Dominant vegetation differentiation was associated with a complex set of environmental variables. A general trend differentiated cold and continental areas from relatively warm and weakly continental areas, and several soil chemical and physical variables were associated with this broad-scaled differentiation. Especially soil chemical variables related to soil acidity (pH, Ca) showed linear relationships with the dominant vegetation gradient. This was closely related to increasing cryoperturbation, decreasing precipitation and cooler conditions. Remarkable differences among relatively adjacent sites suggest that local factors such as geological properties and lemming grazing may strongly drive vegetation differentiation. Conclusions: Vegetation differentiation in tundra areas conforms to a major ecocline underlain by a complex set of environmental gradients, where precipitation, thermal conditions and soil chemical and physical processes are coupled. However, local factors such as bedrock conditions and lemming grazing may cause marked deviations from the general climate-vegetation models. Overall, soil chemical factors (pH, Ca) turned out to have linear relationship with the broad-scale differentiation of arctic vegetation. [source] Northern Environment Predisposes Birches to Ozone DamagePLANT BIOLOGY, Issue 2 2007E. Oksanen Abstract: Ozone sensitivity of silver birch (Betula pendula Roth) has been thoroughly investigated since early 1990,s in Finland. In our long-term open-field experiments the annual percentage reduction in basal diameter and stem volume increment were the best non-destructive growth indicators for ozone impact when plotted against AOTX. Remarkable differences in defence strategies, stomatal conductance, and defence compounds (phenolics), clearly indicate that external exposure indices are ineffective for accurate risk assessment for birch. For flux-based approaches, site-specific values for gmax and gdark are necessary, and determinants for detoxification capacity, ageing of leaves, and cumulative ozone impact would be needed for further model development. Increasing CO2 seems to counteract negative ozone responses in birch, whereas exposure to springtime frost may seriously exacerbate ozone damage in northern conditions. Therefore, we need to proceed towards incorporating the most important climate change factors in any attempts for ozone risk assessment. [source] Differences in endoscopic views during biopsy through the right and left lower biopsy channels of the upper gastrointestinal endoscopeDIGESTIVE ENDOSCOPY, Issue 3 2004Naoki Mantani Background:, It has not been established as to which side the biopsy (instrument) channel should be placed in the tip of a front-viewing upper gastrointestinal (GI) endoscope to allow an en-face approach to lesions on various aspects of the stomach wall. Methods:, Using a front-viewing two-channel endoscope, we identi,ed a difference in endoscopic views during biopsy between lower-right and lower-left channels. Colored marks were distributed on the lesser curvature (LC), greater curvature (GC), anterior wall (AW), and posterior wall (PW) in the ,stomach' of a dummy for mock-performance of upper GI endoscopy. When biopsy forceps through the different channels touched the marks, an endoscopic photograph was taken. Furthermore, when biopsy specimens were obtained from PW lesions in several patients, endoscopic views were compared between the two biopsy channels. Results:, In the dummy study, no remarkable difference was detected in targeting the marks on AW, LC, or GC of the stomach. The dummy and the patient study showed that the lower-right approach could target PW lesions with a more adequate endoscopic view than from the lower left. The lower-left approach targeted PW lesions on the higher body with a nearly blinded endoscopic view. Specimens from PW of the upper body, which could be precisely obtained under direct visual control through the lower-right channel, were no smaller than those obtained using the channel on the lower left. Conclusion:, The present study suggests that the lower-right channel may be preferable to the lower-left channel in the tip of a front-viewing upper GI endoscope. [source] Comparative study on antibodies to human and bacterial 60 kDa heat shock proteins in a large cohort of patients with coronary heart disease and healthy subjectsEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 4 2001Z. Prohászka Background Recent observations indicate an association between antibodies against mycobacterial heat shock protein (hsp65) and coronary heart disease (CHD). Previously, we reported on marked differences in antigen specificity and complement activating ability of anti-hsp65 antibodies and auto-antibodies against human heat shock protein, hsp60. Here, we investigated whether there are differences between antih-sp65 and anti-hsp60 antibodies in their association with CHD. Design We measured by ELISA the levels of antibodies to hsp65, hsp60 and E. coli -derived GroEL in three groups: Group I, 357 patients with severe CHD who underwent by-pass surgery; Group II, 67 patients with negative coronary angiography; Group III, 321 healthy blood donors. Antibodies against Helicobacter pylori were also measured by commercial ELISA. Results As calculated by multiple regression analysis, the levels of anti-hsp60 auto-antibodies were significantly higher in Group I compared to Group II (P = 0·007) or Group III (P < 0·0001). By contrast, although concentrations of anti-hsp65 and anti-GroEL antibodies in Group I were higher than in Group III, no significant differences between Group I and Group II were found. Antibodies to the two bacterial hsp strongly correlated to each other, but either did not correlate or weakly correlated to hsp60. In Group I, serum concentrations of anti- H.pylori antibodies significantly correlated with those of anti-hsp65 and anti-GroEL antibodies but they did not correlate with the anti-hsp60 antibodies. Conclusion As to their clinical relevance, a remarkable difference become evident between antibodies to human hsp60 and antibodies against bacterial hsp in the extent of association with CHD. On the basis of these findings and some pertinent literature data, an alternative explanation for the association between high level of anti-hsp antibodies and atherosclerotic vascular diseases is raised. [source] Enantioselective Ag-Catalyzed Allylation of Aldimines,EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 30 2009Marina Naodovic Abstract A highly enantioselective synthesis of homoallylic amines, using allyltrimethoxysilane under AgI catalytic conditions, has been developed. Among the chiral ligands investigated, a remarkable difference in the resulting AgI complexes was observed. Under mild conditions and low catalyst loadings, homoallylamines were produced in high ee values (up to 80,%) and good yields. The methodology can be further extended to a diastere- and enantioselective crotylation of aldimines.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Deslipping of Ester Rotaxanes: A Cooperative Interplay of Hydrogen Bonding with Rotational BarriersEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 24 2003Petra Linnartz Abstract A series of rotaxanes has been synthesized which contain two ester groups in their axles. All rotaxanes bear the same tetralactam wheel. The kinetics of the de-slipping reaction of these rotaxanes were monitored in tetrachloroethane (TCE) and dimethyl sulfoxide (DMSO) resulting in the observation of a significant solvent effect. In TCE, two isomeric rotaxanes that differ merely with respect to the orientation of the ester groups show a remarkable difference in their deslipping behavior. When the ester carbonyl group is directly attached to the axle center piece, the rotaxane decomposes with a half life of ca. 10 h at 100 °C. The reverse orientation with the carbonyl group attached to the stopper blocks deslipping almost completely and a lower limit for the half life at 100 °C of 25,000 h was obtained. These results can be interpreted by inferring a cooperative action of hydrogen bonding between wheel and axle and differences in rotational barriers. Molecular modeling and AM1 calculations support this interpretation. The implications of these results for the determination of steric size and the optimization of molecular machines are discussed. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003) [source] Photoregulation of DNA transcription by using photoresponsive T7 promoters and clarification of its mechanismFEBS JOURNAL, Issue 6 2010Xingguo Liang With the use of photoresponsive T7 promoters tethering two 2,-methylazobenzenes or 2,,6,-dimethylazobenzenes, highly efficient photoregulation of DNA transcription was obtained. After UV-A light irradiation (320,400 nm), the rate of transcription with T7 RNA polymerase and a photoresponsive promoter involving two 2,,6,-dimethylazobenzenes was 10-fold faster than that after visible light irradiation (400,600 nm). By attaching a nonmodified azobenzene and 2,,6,-dimethylazobenzene at the two positions, respectively, and by utilizing the different cis,trans thermal stability between cis -nonmodified azobenzene and cis- 2,,6,-dimethylazobenzene, four species of T7 promoter (cis,cis, trans,cis, cis,trans, and trans,trans) were obtained. The four species showed transcriptional activity in the order of cis,cis > cis,trans > trans,cis > trans,trans. Kinetic analysis revealed that the Km for the cis,cis promoter (both of the introduced azobenzene derivatives were in the cis form) and T7 RNA polymerase was 68 times lower than that for the trans,trans form, indicating that high photoregulatory efficiency was mainly due to a remarkable difference in affinity for RNA polymerase. The present approach is promising for the creation of biological tools for artificially controlling gene expression, and as a photocontrolled system for supplying RNA fuel for RNA-powered molecular nanomachines. [source] Redistribution of the sheep neonatal Fc receptor in the mammary gland around the time of parturition in ewes and its localization in the small intestine of neonatal lambsIMMUNOLOGY, Issue 3 2002Balázs Mayer Summary Maternal immunity is mediated exclusively by colostral immunoglobulins in ruminants. As the neonatal Fc receptor (FcRn) is suggested to be involved in the transport of immunoglobulin G (IgG) in the mammary gland, we cloned this receptor from sheep and analysed its expression in the mammary gland around the time of parturition and also in the small intestine from the newborn lamb. FcRn heavy-chain mRNA was detected (by using in situ hybridization) exclusively in the acinar and ductal epithelial cells in mammary gland biopsies both before and after parturition. Immunohistochemistry revealed that the cytoplasm of the epithelial cells of the acini and ducts in the mammary gland biopsies stained homogeneously before parturition. A remarkable difference was observed in the pattern after lambing, where the apical side of the cells was strongly stained. The presence of the FcRn in the acinar and ductal epithelial cells of the mammary gland, and the obvious change in distribution before and after parturition, indicate that the FcRn plays an important role in the transport of IgG during colostrum formation in ruminants. Immunohistochemical analysis detected a strong apical and a weak basal FcRn signal in the duodenal crypt cells of a neonatal lamb, which have been previously demonstrated to secrete IgG1 in newborn ruminants. The FcRn was not detected in the duodenal enterocytes, which absorb intact IgG from the colostrum in a non-specific manner. These data suggest that FcRn is involved in IgG1 secretion in ruminant epithelial cells. [source] Maternal and fetal microvasculature in sheep placenta at several stages of gestationJOURNAL OF ANATOMY, Issue 3 2010Shireen A. Hafez Abstract Maternal and fetal microvasculature was studied in ewes at days 50, 90 and 130 of gestation using microvascular corrosion casting and scanning electron microscopy. Microvascular corrosion casts of caruncles at day 50 were cup-shaped with a centrally located cavity. Branches of radial arteries entered the caruncle from its base and ramified on the maternal surface of the caruncle. Stem arteries broke into an extensive mesh of capillaries forming crypts on the fetal surface. The architecture of the caruncle at day 90 was similar to what was found at day 50 but the vascularity and the depth of the crypts increased in correspondence to increased branching of fetal villi. The substance of the caruncle was thicker at day 130 compared with day 50, with no remarkable difference compared with day 90. Capillary sinusoids of irregular form and diameter were observed on the fetal surface of the caruncle at all stages. These sinusoids may reduce blood flow resistance and subsequently increase transplacental exchange capacity. A microvascular corrosion cast of the cotyledon was cup-shaped with wide and narrow sides. Cotyledonary vessels entered and left the cotyledon from the narrow side. A cotyledonary artery gave proximal collateral branches immediately after entering the cotyledon and then further branched to supply the remaining portion of the cotyledon. Vessel branches broke into a mesh of capillaries forming the fetal vascular villi. Fetal villi that were nearest to the center of the cotyledon were the longest. Capillaries forming villi were in the form of a web-like mesh, were irregular in size and had sinusoidal dilations. The architecture of the cotyledon at day 90 was similar to day 50, but the vascularity increased. Branching of the fetal villi became more abundant. This extensive branching presumably allows a higher degree of invasion and surface contact to maternal tissues. At day 130, the distal portions of the fetal villi showed low ridges and troughs to increase the surface area for diffusion. Branching of fetal villi appears to influence the elaboration of maternal crypts in all stages of gestation. However, correspondence between crypts and villi is restricted to distal portions of fetal villi. [source] Gas phase isomeric differentiation of oleanolic and ursolic acids associated with heptakis-(2,6-di- O -methyl)-,-cyclodextrin by electrospray ionization Fourier transform ion cyclotron resonance mass spectrometryJOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 4 2010Zhan Yu Abstract Oleanolic acid (OA) and ursolic acid (UA) are isomeric triterpenoid compounds with similar pharmaceutical properties. Usually, modern chromatographic and electrophoretic methods are widely utilized to differentiate these two compounds. Compared with mass spectrometric (MS) methods, these modern separation methods are both time- and sample-consuming. Herein, we present a new method for structural differentiation of OA and UA by Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) with the association of heptakis-(2,6-di- O -methyl)-,-cyclodextrin (DM-,-CD). Exact MS and tandem MS (MS/MS) data showed that there is no perceptible difference between OA and UA, as well as their ,-cyclodextrin and ,-cyclodextrin complexes. However, there is a remarkable difference in MS/MS spectra of DM-,-CD complexes of OA and UA. The peak corresponding to the neutral loss of a formic acid and a water molecule could only be observed in the MS/MS spectrum of the complex of DM-,-CD : OA. Molecular modeling calculations were also employed to further investigate the structural differences of DM-,-CD : OA and DM-,-CD : UA complexes. Therefore, by employing DM-,-CD as a reference reagent, OA and UA could be differentiated with purely MS method. Copyright © 2010 John Wiley & Sons, Ltd. [source] A remarkable difference in the deprotonation steps of the Friedel,Crafts acylation and alkylation reactionsJOURNAL OF PHYSICAL ORGANIC CHEMISTRY, Issue 11 2009Shinichi Yamabe Abstract Friedel,Crafts acylation and alkylation reactions were investigated using density functional theory calculations. The reaction systems studied were (benzene,+,acetyl chloride,+,Al2Cl6 (or AlCl3)) and (benzene,+,2-chloropropane,+,Al2Cl6). In the acylation reaction, the acylium ion intermediate is reached either via a MeC(Cl)OAl2Cl6 complex or via direct Cl transfer: MeC(O)ClAl2Cl6,,,MeCO,+Al2Cl. The ion adds to benzene electrophilically to form a Wheland intermediate containing a strong CHCl hydrogen bond, which leads to deprotonation and the subsequent formation of acetophenone. The resulting HClAl2Cl6 fragment is subjected to a nucleophilic attack by the carbonyl oxygen of the acetophenone, and recovery of the Al2Cl6 bridge is unlikely. Attack of the Al2Cl6 moiety by MeC(Cl)O gives the complex MeC(Cl)O,AlCl3, whose reactivity toward acylation is similar to that of the MeC(Cl)O,Al2Cl6 complex. In the alkylation reaction, deprotonation does not take place, but rather a [1,2] H-shift from the Wheland intermediate. The resulting , -protonated cumene undergoes deprotonation, with subsequent recovery of the Al2Cl6 bridge. In addition, the Al2Cl6 -catalyzed isomerization of the n -propyl to the isopropyl cation was found to be a dyotropic shift. Copyright © 2009 John Wiley & Sons, Ltd. [source] Executive dysfunction can explain word-list learning disability in very mild Alzheimer's disease: The Tajiri ProjectPSYCHIATRY AND CLINICAL NEUROSCIENCES, Issue 1 2004RYUSAKU HASHIMOTO msc Abstract, Elderly people with questionable dementia (i.e. a Clinical Dementia Rating (CDR) of 0.5) have been focused on as representing the borderline zone condition between healthy people and dementia patients. Many of them are known to have pathologic traits of very mild Alzheimer's disease (AD). Although they present mild memory disorder, the underlying mechanism has not been fully investigated. Herein is reported the mechanism of learning disability in very mild AD. Eighty-six CDR 0.5 participants and 101 age- and education-matched healthy controls (CDR 0) were randomly selected from a community in the town of Tajiri, Miyagi Prefecture. The word-recall task of the Alzheimer Disease Assessment Scale,Japanese (i.e. learning and recall of 10 words) was administered. The numbers of words recalled in each trial and those never recalled throughout the trials were compared for the two CDR groups. The serial-position function was depicted for three parts (i.e. primary, middle, and recency). The CDR 0.5 group recalled significantly fewer words than the CDR 0 group. The number of never-recalled words was greater in the CDR 0.5 group. A remarkable difference was found in the middle part of the word list. The number of never-recalled words of the CDR 0.5 group was greater in the middle part. The large number of never-recalled words accounted for the poor learning performance of very mild AD participants. The results suggested that very mild AD participants have difficulty in learning and retaining words in the middle part of the word-list because of a functional decline of the central executive system. [source] The Effects of Supraoptimal Temperatures on Population Growth and Cortical Patterning in Tetrahymena pyriformis and Tetrahymena thermophila: A ComparisonTHE JOURNAL OF EUKARYOTIC MICROBIOLOGY, Issue 2 2001JOSEPH FRANKEL ABSTRACT. In this investigation, we compare the multiplication rates and morphogenetic responses of the two most studied Tetrahymena species, T. pyriformis and T. thermophila, at supraoptimal temperatures. Although the upper temperature limits differ greatly in the two species, the pattern of growth responses to high temperature is for the most part similar, with some differences in detail. The transient recovery of cell division at the highest temperature that allows cell division, characteristic of T. pyriformis, is observed in a less distinct form in T. thermophila. Moreover, there is a remarkable difference in developmental response, with drastic abnormalities in patterning of oral structures during the transient recovery of cell division in T. pyriformis, and far more limited abnormalities under similar conditions in T. thermophila. The abnormalities result from spatial disorder in the alignment and orientation of basal body pairs within the early oral primordium, followed by failures in the realignment that normally occurs as oral structures (membranelles and undulating membrane) mature. Both the initial spatial disorder and the failures in realignment are far more severe in T. pyriformis than in T. thermophila. [source] The structure of a d(gcGAACgc) duplex containing two consecutive bulged A residues in both strands suggests a molecular switchACTA CRYSTALLOGRAPHICA SECTION D, Issue 6 2007Jiro Kondo In previous studies, it was reported that DNA fragments with the sequence d(gcGXYAgc) (where X = A or G and Y = A, T or G) form a stable base-intercalated duplex (Bi-duplex) in which the central X and Y residues are not involved in any base-pair interactions but are alternately stacked on each other between the two strands. To investigate the structural stability of the Bi-duplex, the crystal structure of d(gcGAACgc) with a point mutation at the sixth residue of the sequence, d(gcGAAAgc), has been determined. The two strands are associated in an antiparallel fashion to form two types of bulge-containing duplexes (Bc-duplexes), I and II, both of which are quite different from the Bi-duplex of the parent sequence. In both Bc-duplexes, three Watson,Crick G·C base pairs constitute the stem regions at the two ends. The A4 residues are bulged in to form a pair with the corresponding A4 residue of the opposite strand in either duplex. The A4·A4* pair formation is correlated to the orientations of the adjacent A5 residues. A remarkable difference between the two Bc-duplexes is seen at the A5 residue. In Bc-duplex I, it is flipped out and comes back to interact with the G3 residue. In Bc-duplex II, the A5 residue extends outwards to interact with the G7 residue of the neighbouring Bc-duplex I. These results indicate that trans sugar-edge/Hoogsteen (sheared-type) G3·A6* base pairs are essential in the formation of a Bi-duplex of d(gcGXYAgc). On the other hand, the alternative conformations of the internal loops containing two consecutive bulged A residues suggest molecular switching. [source] The protein content in crystals and packing coefficients in different space groupsACTA CRYSTALLOGRAPHICA SECTION D, Issue 7 2000Klas M. Andersson A precise way of estimating the packing coefficient, i.e. the ratio between the protein and unit-cell volume, or solvent content in protein crystals is given. At present, the solvent content is not given for most proteins in the Protein Data Bank and in many cases where it is given the values are dubious. The mean density of proteins in the crystalline form is around 1.22,g,cm,3, not 1.35,g,cm,3 as usually stated. This is equivalent to 19.5,Å3 per non-H atom. A statistical investigation of the average protein content and packing coefficient in different space groups is presented. The packing coefficients are generally higher in the most frequently occurring space groups than in the uncommon space groups. There is also a remarkable difference in frequency distribution for enantiomorphous pairs of space groups. [source] Ghrelin: more than a natural GH secretagogue and/or an orexigenic factorCLINICAL ENDOCRINOLOGY, Issue 1 2005E. Ghigo Summary Ghrelin, an acylated peptide produced predominantly by the stomach, has been discovered to be a natural ligand of the growth hormone secretagogue receptor type 1a (GHS-R1a). Ghrelin has recently attracted considerable interest as a new orexigenic factor. However, ghrelin exerts several other neuroendocrine, metabolic and also nonendocrine actions that are explained by the widespread distribution of ghrelin and GHS-R expression. The likely existence of GHS-R subtypes and evidence that the neuroendocrine actions, but not all the other actions, of ghrelin depend on its acylation in serine-3 revealed a system whose complexity had not been completely explored by studying synthetic GHS. Ghrelin secretion is mainly regulated by metabolic signals and, in turn, the modulatory action of ghrelin on the control of food intake and energy metabolism seems to be among its most important biological actions. However, according to a recent study, ghrelin-null mice are neither anorectics nor dwarfs and this evidence clearly depicts a remarkable difference from leptin null mice. Nevertheless, the original and fascinating story of ghrelin, as well as its potential pathophysiological implications in endocrinology and internal medicine, is not definitively cancelled by these data as GHS-R1a null aged mice show significant alterations in body composition and growth, in glucose metabolism, cardiac function and contextual memory. Besides potential clinical implications for natural or synthetic ghrelin analogues acting as agonists or antagonists, there are several open questions awaiting an answer. How many ghrelin receptor subtypes exist? Is ghrelin ,the' or just ,a' GHS-R ligand? That is, are there other natural GHS-R ligands? Is there a functional balance between acylated and unacylated ghrelin forms, potentially with different actions? Within the next few years suitable answers to these questions will probably be found, making it possible to gain a better knowledge of ghrelin's potential clinical perspectives. [source] Sensitivity of multi-coil frequency domain electromagnetic induction sensors to map soil magnetic susceptibilityEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 4 2010D. Simpson Magnetic susceptibility is an important indicator of anthropogenic disturbance in the natural soil. This property is often mapped with magnetic gradiometers in archaeological prospection studies. It is also detected with frequency domain electromagnetic induction (FDEM) sensors, which have the advantage that they can simultaneously measure the electrical conductivity. The detection level of FDEM sensors for magnetic structures is very dependent on the coil configuration. Apart from theoretical modelling studies, a thorough investigation with field models has not been conducted until now. Therefore, the goal of this study was to test multiple coil configurations on a test field with naturally enhanced magnetic susceptibility in the topsoil and with different types of structures mimicking real archaeological features. Two FDEM sensors were used with coil separations between 0.5 and 2 m and with three coil orientations. First, a vertical sounding was conducted over the undisturbed soil to test the validity of a theoretical layered model, which can be used to infer the depth sensitivity of the coil configurations. The modelled sounding values corresponded well with the measured data, which means that the theoretical models are applicable to layered soils. Second, magnetic structures were buried in the site and the resulting anomalies measured to a very high resolution. The results showed remarkable differences in amplitude and complexity between the responses of the coil configurations. The 2-m horizontal coplanar and 1.1-m perpendicular coil configurations produced the clearest anomalies and resembled best a gradiometer measurement. [source] Ageing and the tax implied in public pension schemes: simulations for selected OECD countriesFISCAL STUDIES, Issue 2 2004Robert Fenge Abstract A key figure suited to measuring intergenerational imbalances in unfunded public pension schemes is given by the ,implicit tax rate' imposed on each generation's lifetime income. The implicit tax arises from the fact that, quite generally, pension benefits fall short of actuarial returns to contributions paid to these systems while actively working. Under current pension policies, implicit tax rates will increase sharply for younger generations in most industrialised countries. In this paper, this is illustrated for the cases of France, Germany, Italy, Japan, Sweden, the UK and the USA. Nevertheless, there are remarkable differences across countries regarding both the level of implicit taxes and their development over successive age cohorts, which can be attributed to differences in ageing processes and in the institutional features of national pension systems. In addition, we can demonstrate how effective different approaches to pension reform are in smoothing the intergenerational profile of implicit tax rates. [source] Composition and antifungal activity of essential oils isolated from Hypericum hyssopifolium and Hypericum heterophyllumFLAVOUR AND FRAGRANCE JOURNAL, Issue 1 2004A. Cakir Abstract The composition of the hydrodistilled essential oils obtained from the aerial parts of Hypericum hyssopifolium subsp. elongatum var. elongatum and H. heterophyllum Vent. were analysed by means of GC and GC,MS, and 66 compounds were determined in total. The oils showed remarkable differences in chemical composition. The oil of H. hyssopifolium, which is rich in monoterpenes, consists primarily of , -pinene (57.3%), , -pinene (9.0%), limonene (6.2%) and , -phellandrene (4.4%). The oil of H. heterophyllum was a complex mixture consisting mainly of sesquiterpenes (72.9% of the total oil). In this oil, isocaryophyllene (17.1%), , -pinene (11.6%), , -cadinene (9.5%), , -muurolene (8.2%), n -decane (5.8%), , -cadinene (5.5%) and , -caryophyllene (4.5%) were found to be major constituents. The two essential oils were tested for antifungal activity using microbial growth inhibition assays in vitro against 10 agricultural pathogenic fungi, which consisted of ,ve Fusarium species (F. oxysporum, F. culmorum, F. sambucinum, F. solani and F. acuminatum) and ,ve anastomosis groups of Rhizoctonia solani (AG-3, AG-4, AG-5, AG-9 and AG-11). In general, the oils showed moderate activity against several fungal species, viz F. acuminatum, AG-5 and AG-11. The most signi,cant results were obtained against AG-11 for H. heterophyllum oil. However, both oils increased the growth of some fungal species. In addition, the antifungal activity of 13 pure compounds identi,ed as major components in the essential oils of the Hypericum species studied were determined using microbial growth inhibition assays against the 10 fungal species mentioned above. Among these compounds, both , -caryophyllene oxide and , -terpineol were inhibitory to the growth of all fungi. Copyright © 2003 John Wiley & Sons, Ltd. [source] Frost formation on a bionic super-hydrophobic surface under natural convection conditionsHEAT TRANSFER - ASIAN RESEARCH (FORMERLY HEAT TRANSFER-JAPANESE RESEARCH), Issue 7 2008Yunjun Gou Abstract A bionic super-hydrophobic surface has a multiple micro-nano-binary structure (MNBS) similar to the lotus leaf surface microstructure. This kind of surface has a contact angle of water greater than 150° and a roll angle smaller than 5°. In this paper, the frost deposition phenomena on a bionic super-hydrophobic surface were observed. The surface has many micro bumps and its contact angle is 162°. The formation of water droplets, the droplet freezing process, the formation of initial frost crystals and the frost layer structure on a cold bionic super-hydrophobic surface under natural convection conditions were closely observed. The frost layer structure formed on the super-hydrophobic surface shows remarkable differences to that on a plain copper surface: the structure is weaker, looser, thin, and easily removed and most importantly, it is of a very special pattern, a pattern similar to a chrysanthemum, a frost layer structure that has not been reported before to the best of the present authors knowledge. The experimental results also show that a super-hydrophobic surface has a strong ability to restrain frost growth. The frost deposition on this bionic surface was delayed 55 minutes when compared with a plain copper surface under the conditions of a cold plate temperature of ,10.1°C, air temperature of 18.4°C, and relative humidity of 40%. A theoretical analysis was also presented to explain the observed phenomena. © 2008 Wiley Periodicals, Inc. Heat Trans Asian Res, 37(7): 412,420, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20216 [source] Location-related differences in structure and function of the stratum corneum with special emphasis on those of the facial skinINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 6 2008H. Tagami Synopsis Between the two different kinds of the skin covering the body, the glabrous skin is found only on the palmo-plantar surface because of its rather simple function to protect the underlying living tissue with its remarkably thick stratum corneum (SC) from strong external force and friction. Thus, its barrier function is extremely poor. In contrast, the hair-bearing skin covers almost all over the body surface regardless of the presence of long hair or vellus hair. In regard to its SC, many dermatologists and skin scientists think that it is too thin to show any site-specific differences, because the SC is just present as an efficient barrier membrane to protect our body from desiccation as well as against the invasion by external injurious agents. However, there are remarkable regional differences not only in the living skin tissue but also even in such thin SC reflecting the function of each anatomical location. These differences in the SC have been mostly disclosed with the advent of non-invasive biophysical instruments, particularly the one that enables us to measure transepidermal water loss (TEWL), the parameter of the SC barrier function, and the one that evaluates the hydration state of the skin surface, the parameter of the water-holding capacity of the SC that brings about softness and smoothness to the skin surface. These in vivo instrumental measurements of the SC have disclosed the presence of remarkable differences in the functional properties of the SC particularly between the face and other portions of the body. The SC of the facial skin is thinner, being composed of smaller layers of corneocytes than that of the trunk and limbs. It shows unique functional characteristics to provide hydrated skin surface but relatively poor barrier function, which is similar to that observed in retinoid-treated skin or to that of fresh scar or keloidal scars. Moreover, there even exist unexpected, site-dependent differences in the SC of the facial skin such as the forehead, eyelid, cheek, nose and perioral regions, although each location occupies only a small area. Between these locations, the cheek shows the lowest TEWL in contrast to the perioral region that reveals the highest one. Moreover, these features are not static but change with age particularly between children and adults and maybe also between genders. Among various facial locations, the eyelid skin is distinct from others because its SC is associated with poor skin surface lipids and a thin SC cell layer composed of large corneocytes that brings about high surface hydration state but poor barrier function, whereas the vermillion borders of the lips that are covered by an exposed part of the oral mucosa exhibit remarkably poor barrier function and low hydration state. Future studies aiming at the establishment of the functional mapping in each facial region and in other body regions will shed light on more delicate site-dependent differences, which will provide us important information in planning the strategy to start so called tailor-made skin care for each location of the body. Résumé Entre les deux types différents de peau couvrant le crops, on trouve la peau glabre uniquement sur la surface palmo-plantaire du fait de sa fonction plutôt simple de protection du tissu vivant sous-jacent par un stratum corneum (SC) trés épais vis-à-vis des forces extérieures et de la friction. De ce fait, sa fonction barrière est extrêmement pauvre. Au contraire, la peau velue courve la presque totalité de la surface du crops, que ce soit par la présence de longs cheveux ou de duvet. En ce qui concerne son SC, la plupart des dermatologues et des scientifiques de la peau pensent qu'il est trop mince pour montrer une différence spécifique au site, attendu que le SC est simplement présent en tant que membrane barriére efficace pour protéger notre corps de la dessiccation ainsi que pour lutter contre l'invasion d'agents nuisibles externes. Cependant, il existe des différences importantes entre les sites, non seulement dans la peau vivante, mais également dans ce SC aussi mince, qui révèlent la fonctin de chaque site anatomique. Ces différences dans le SC ont surtout été révélées avec l'apparition d'instruments biophysiques non invasifs, en particulier celui qui nous permet de mesurer la perte transépidermale en eau (TEWL), le paramétre de la fonction barrière du SC et celui qui évalue l'état d'hydratation de la surface de peau, le paramètre de la capacité en rétention de l'eau du SC qui est liéà la souplesse et à la douceur à la surface de peau. Ces mesures instrumentales in vivo du SC ont révélé la présence de différences remarquables entre les propriétés fonctionnelles du SC particulièrement entre le visage et d'autres parties du corps. Le SC de la peau de la face est plus mince, car li est composé de couches plus petites de corneocytes que celui du tronc et des membres. Il montre des caractéristiques fonctionnelles uniques pour permettre l'hydratation de la surface de peau, mais une fonction barrière relativement faible, semblable à celle observée dans la peau traitée avec un rétinoïde ou à celle d'une cicatrice récente ou de cicatrices kéloidales. De plus, il existe des différences sites-dépendantes inattendues dans le SC de la peau de la face comme le front, la paupière, la joue, le nez et les régions périorales, et ce, bien que chaque emplacement occupe seulement un petit secteur. Entre ces divers emplacements, la joue montre le TEWL le plus bas par comparaison avec la région périorale qui montre le plus élevé. De plus, ces caractéristiques ne sont pas fixes, mais changent avec l'âge en particulier entre enfants et adultes et peut-être aussi entre sexes. Entre les diverses régions de la face, la peau de la paupière se distingue parce que son SC est associéà une peau pauvre en lipides de surface constituée par une mince couche de cellule composée de grand cornéocytes qui provoquent un haut état d'hydratation superficiel, mais une faible fonction barrière. A l'inverse les bordures vermillion des lévres recouvertes par une partie exposée de muqueuse orale, possèdent une fonction barrière très faible et un état d'hydratation bas. Les études futures visant àétablir la configuration fonctionnelle de chaque région de la face et d'autres régions du corps mettrons en lumière des différences sites-dépendantes plus subtiles, qui nous fourniront des informations importantes pour planifier la stratégie pour commencer le soin de la peau sur mesure si attendu pour chaque partie du corps. [source] A comparative in situ Rietveld refinement study: thermal decomposition and transformation of CoAl and CoZnAl layered double hydroxidesJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 6 2008Rune E. Johnsen Rietveld refinement based on in situ X-ray powder diffraction (XRPD) data was combined with thermogravimetric analysis (TGA) and mass spectrometry (MS) to study and compare the phase transformations, thermal stability, microstructural and structural changes of two cobalt-containing nitrate-based layered double hydroxides (LDHs) upon heating in a controlled inert atmosphere of nitrogen. The XRPD data were collected, using synchrotron X-ray radiation, with a time resolution of 107,s, which made it possible to carry out detailed structural studies of the initial layered double hydroxides as well as their decomposition products: spinel for a CoAl,NO3 LDH and spinel/zincite for a CoZnAl,NO3 LDH. Correlating these data with those from the TGA,MS analyses gives us information about the transformation mechanisms. Rietveld refinements of the two spinel phases reveal remarkable differences. The a axis of the spinel formed by decomposition of the CoAl,NO3 LDH increases almost linearly from approximately 598 to 1163,K, mainly due to the dominating thermal expansion, whereas the a axis of the spinel formed by decomposition of the CoZnAl,NO3 shows a more complex temperature dependency. Between approximately 698 and 1073,K, the a axis is almost constant due to pronounced chemical interaction with an additional amorphous phase and the zincite phase, whereas from 1073 up to 1163,K it increases linearly. Calculations, based on the results of the Rietveld refinements, of the size of the octahedral and tetrahedral coordination polyhedra in the spinel show that the octahedra shrink and the tetrahedra expand with increasing temperature. The unusual thermal behaviour of the octahedra is discussed and attributed to the low formation temperature of the cobalt aluminium spinel phase. Finally, the intensity of a low-angle scattering (LAS) signal observed in the XRPD patterns was correlated with the decomposition of the LDH, and determination of the specific surface areas gave the temperature-dependent BET surface areas. [source] Application of two-dimensional near-infrared (2D-NIR) correlation spectroscopy to the discrimination of three species of DendrobiumJOURNAL OF CHEMOMETRICS, Issue 9 2009Caiyun Wang Abstract The objective of this paper was to apply two-dimensional (2D) near-infrared (NIR) correlation spectroscopy to the discrimination of three species of Dendrobium. Generalized 2D-NIR correlation spectroscopy was able to enhance spectral resolution, simplify the spectrum with overlapped bands and provide information about temperature-induced spectral intensity variations that was hard to obtain from one-dimensional NIR spectroscopy. The FT-NIR spectra were measured over a temperature range of 30,140°C. The 2D synchronous and asynchronous spectra showed remarkable differences within the range of 5600,4750,cm,1 between different species of Dendrobium. Copyright © 2009 John Wiley & Sons, Ltd. [source] Differences in prevalence of pressure ulcers between the Netherlands and Germany , associations between risk, prevention and occurrence of pressure ulcers in hospitals and nursing homesJOURNAL OF CLINICAL NURSING, Issue 9 2008Antje Tannen MA Aim., This study compares pressure ulcer prevalence and prevention activities in nursing homes and hospitals within two European countries. Background., Over three years stable differences have been found between the Netherlands (NL) and Germany (GER) with higher pressure ulcer rates in the NL. As previous analyses have shown, the differences cannot be entirely explained by differences in the population's vulnerability to pressure ulcers because they still remain after risk adjustment. Therefore, the differences in prevalence must be caused by other factors. The purpose of this study is to analyse if any potential differences in preventive activities can account for the varying occurrence of pressure ulcers. Method., In both countries, nation-wide surveys were conducted annually using the same standardised questionnaires. Trained nurses examined all consenting patients of the voluntarily participating facilities. This examination included a skin assessment of the entire body. Data regarding risk factors, prevention and details about wounds were then collected. Results., In-patients of 29 German (n = 2531) and 71 Dutch (n = 10 098) nursing homes and 39 German (n = 8515) and 60 Dutch (n = 10 237) hospitals were investigated. The use of pressure-reducing devices was more common in the NL than in GER, but all other interventions were more frequently provided to German risk patients than to their Dutch counterparts. The pressure ulcer prevalence was significantly higher in the Dutch sample. After adjusting for gender, age, Braden Score and prevention, the probability of having a pressure ulcer was 8·1 times higher for Dutch nursing home residents than for German residents. Conclusion., Some of the variance in pressure ulcer prevalence between the two countries can be explained by varying pressure ulcer prevention. However, some remarkable differences still remain unexplained. Relevance to clinical practice., The extent of pressure ulcer prevention, especially repositioning and nutrition intervention provided to patients at risk, is not in accordance with international guidelines. [source] Molecular characterization of the env gene of two CCR5/CXCR4-independent human immunodeficiency 2 primary isolates,JOURNAL OF MEDICAL VIROLOGY, Issue 11 2009Quirina Santos-Costa Abstract Human immunodeficiency virus 2 (HIV-2) infection is characterized by a slower disease progression and lower transmission rates. The molecular features that could be assigned as directly involved in this in vivo phenotype remain essentially unknown, and the importance of HIV-2 as a model to understand pathogenicity of HIV infection has been frequently underestimated. The early events of the HIV replication cycle involve the interaction between viral envelope glycoproteins and cellular receptors: the CD4 molecule and a chemokine receptor, usually CCR5 or CXCR4. Despite the importance of these two chemokine receptors in human immunodeficiency virus 1 (HIV-1) entry into cells, we have previously shown that in some HIV-2 asymptomatic individuals, a viral population exists that is unable to use both CCR5 and CXCR4. The goal of the present study was to investigate whether possible regions in the env gene of these viruses might account for this phenotype. From the molecular characterization of these env genes we could not detect any correlation between V3 loop sequence and viral phenotype. In contrast, it reveals the existence of remarkable differences in the V1/V2 and C5 regions of the surface glycoprotein, including the loss of a putative glycosilation site. Moreover, in the transmembrane glycoprotein some unique sequence signatures could be detected in the central ectodomain and second heptad repeat (HR2). Some of the mutations affect well-conserved residues, and may affect the conformation and/or the dynamics of envelope glycoproteins complex, including the SU,TM association and the modulation of viral entry function. J. Med. Virol. 81:1869,1881, 2009. © 2009 Wiley-Liss, Inc. [source] Use of volumetric computerized tomography as a primary outcome measure to evaluate drug efficacy in the prevention of peri-prosthetic osteolysis: A 1-year clinical pilot of etanercept vs. placeboJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 6 2003Edward M. Schwarz Although total hip replacement (THR) is amongst the most successful and beneficial medical procedures to date, long-term outcomes continue to suffer from aseptic loosening secondary to peri-prosthetic osteolysis. Extensive research over the last two decades has elucidated a central mechanism for osteolysis in which wear debris generated from the implant stimulates inflammatory cells to promote osteoclastogenesis and bone resorption. The cytokine tumor necrosis factor alpha (TNF,) has been demonstrated to be central to this process and is considered to be a leading target for intervention. Unfortunately, even though FDA approved TNF antagonists are available (etanercept), currently there are no reliable outcome measures that can be used to evaluate the efficacy of a drug to prevent peri-prosthetic osteolysis. To the end of developing an effective outcome measure, we evaluated the progression of lesion size in 20 patients with established peri-acetabular osteolysis (mean = 29.99 cm3, range = 2.9,92.7 cm3) of an uncemented primary THR over 1-year, using a novel volumetric computer tomography (3D-CT) technique. We also evaluated polyethylene wear, urine N-telopeptides and functional assessments (WOMAC, SF-36 and Harris Hip Score) for comparison. At the time of entry into the study baseline CT scans were obtained and the patients were randomized to etanercept (25 mg s.q., twice/week) and placebo in a double-blinded fashion. CT scans, urine and functional assessments were also obtained at 6 and 12 months. No serious adverse drug related events were reported, but one patient had to have revision surgery before completion of the study due to aseptic loosening. No remarkable differences between the groups were observed. However, the study was not powered to see significant drug effects. 3D-CT data from the 19 patients was used to determine the mean increase in lesion size over 48 weeks, which was 3.19 cm3 (p < 0.0013). Analysis of the urine N-telopeptides and functional assessment data failed to identify a significant correlation with wear or osteolysis. In conclusion, volumetric CT was able to measure progression of osteolysis over the course of a year, thus providing a technology that could be used in therapeutic trials. Using the data from this pilot we provide a model power calculation for such a trial. © 2003 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved. [source] | ||||||||||||||||||||||||||||||||||