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Reveals Differences (reveal + difference)
Selected AbstractsDouble Oestrogen Receptor , and , Knockout Mice Reveal Differences in Neural Oestrogen-Mediated Progestin Receptor Induction and Female Sexual BehaviourJOURNAL OF NEUROENDOCRINOLOGY, Issue 10 2003A. E. Kudwa Abstract To test the hypothesis that oestrogen receptor , (ER,) and ER, act together to mediate the actions of oestrogen in the ventromedial hypothalamus (VMH), we used mice with single or double knockout mutations of the ER, and ER, genes. Ovariectomized mice were implanted with 17,-oestradiol and killed 5 days later. Oestradiol treatment promoted progestin receptor (PR)-immunoreactivity (-ir) in the VMH of all genotypes, but was maximal in brains of wild-type and ER,KO females. Analysis of specific VMH subregions revealed that PR-ir induction was limited to the caudal VMH in ER,KO and ER,,KO mice. In the rostral VMH, oestradiol only induced PR-ir in wild-type and ER,KO mice, and the number of PR-ir neurones in this region was greater in ER,KO than wild-type females. Next, we tested the ability of a dopamine agonist and progesterone to facilitate sexual behaviour in females lacking functional ER,, ER,, or both receptors. Ovariectomized mice were implanted with oestradiol, and tested for sexual behaviour three times after administration of the dopamine agonist, apomorphine, followed by two tests concurrent with progesterone treatment and a final test with just apomorphine treatment. ER,KO and ER,,KO females failed to display lordosis under any testing conditions, while ER,KO females exhibited lordosis behaviour equal to that of wild-type females. Our data show that a subpopulation of PR-ir neurones is induced by oestradiol in the caudal VMH of female mice lacking both ER, and ER, genes. We hypothesize that this action of oestradiol is either mediated by a novel ER or by the mutant portion of the AF2 subregion of the ER, gene present in ER,KO brain. However, despite the presence of PR in VMH, females lacking a functional ER, gene do not display sexual behaviour, via either ligand-dependent or -independent activation. [source] Marital Satisfaction Among African Americans and Black Caribbeans: Findings From the National Survey of American Life,FAMILY RELATIONS, Issue 2 2008Chalandra M. Bryant Abstract: This study examines the correlates of marital satisfaction using data from a national probability sample of African Americans (N = 962) and Black Caribbeans (N = 560). Findings reveal differences between African Americans and Black Caribbeans, and men and women within those groups, in the predictors of marital satisfaction. Black Caribbean women reported overall higher levels of marital satisfaction than African American women. The findings amply demonstrate the significance of ethnic diversity within the Black population in the United States. Difficulties with finances (budgeting, credit issues, and debt management) are one of the key issues that generate conflict in marriages; stress generated as a result of financial problems can lower marital satisfaction. Because these issues are salient for couples at any given time in the family life cycle, counseling at critical points in the marriage (birth of children, launching of children from home, and retirement) may be helpful. [source] Crystal structure and enzymatic properties of a bacterial family 19 chitinase reveal differences from plant enzymesFEBS JOURNAL, Issue 21 2006Ingunn A. Hoell We describe the cloning, overexpression, purification, characterization and crystal structure of chitinase G, a single-domain family 19 chitinase from the Gram-positive bacterium Streptomyces coelicolor A3(2). Although chitinase G was not capable of releasing 4-methylumbelliferyl from artificial chitooligosaccharide substrates, it was capable of degrading longer chitooligosaccharides at rates similar to those observed for other chitinases. The enzyme was also capable of degrading a colored colloidal chitin substrate (carboxymethyl-chitin,remazol,brilliant violet) and a small, presumably amorphous, subfraction of ,-chitin and ,-chitin, but was not capable of degrading crystalline chitin completely. The crystal structures of chitinase G and a related Streptomyces chitinase, chitinase C [Kezuka Y, Ohishi M, Itoh Y, Watanabe J, Mitsutomi M, Watanabe T & Nonaka T (2006) J Mol Biol358, 472,484], showed that these bacterial family 19 chitinases lack several loops that extend the substrate-binding grooves in family 19 chitinases from plants. In accordance with these structural features, detailed analysis of the degradation of chitooligosaccharides by chitinase G showed that the enzyme has only four subsites (, 2 to +,2), as opposed to six (, 3 to +,3) for plant enzymes. The most prominent structural difference leading to reduced size of the substrate-binding groove is the deletion of a 13-residue loop between the two putatively catalytic glutamates. The importance of these two residues for catalysis was confirmed by a site-directed mutagenesis study. [source] Genome analysis and gene expression profiling of neuroblastoma and ganglioneuroblastoma reveal differences between neuroblastic and Schwannian stromal cellsTHE JOURNAL OF PATHOLOGY, Issue 3 2005Simona Coco Abstract Neuroblastic tumours are a group of paediatric cancers with marked morphological heterogeneity. Neuroblastoma (Schwannian stroma-poor) (NB-SP) is composed of undifferentiated neuroblasts. Ganglioneuroblastoma intermixed (Schwannian stroma-rich) (GNBi-SR) is predominantly composed of Schwannian stromal (SS) and neuroblastic (Nb) cells. There are contrasting reports suggesting that SS cells are non-neoplastic. In the present study, laser capture microdissection (LCM) was employed to isolate SS and Nb cells. Chromosome 1p36 deletion and MYCN gene amplification were found to be associated in two out of seven NB-SPs, whereas no abnormalities were observed in five GNBi-SRs. In some cases, loss of heterozygosity (LOH) at 1p36 loci was detected in Nb cells but not in the bulk tumour by LCM; furthermore, LOH was also identified in both SS and tumour tissue of a GNBi-SR. DNA gain and loss studied by comparative genomic hybridization were observed at several chromosome regions in NB-SP but in few regions of GNBi-SR. Finally, gene expression profiles studied using an oligo-microarray technique displayed two distinct signatures: in the first, 32 genes were expressed in NB-SP and in the second, 14 genes were expressed in GNBi-SR. The results show that NB-SP is composed of different morphologically indistinguishable malignant cell clones harbouring cryptic mutations that are detectable only after LCM. The degree of DNA imbalance is higher in NB-SP than in GNBi-SR. However, when the analysis of chromosome 1p36 is performed at the level of microdissection, LOH is also observed in SS cells. These data provide supportive evidence that SS cells have a less aggressive phenotype and play a role in tumour maturation. Copyright © 2005 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [source] Accurate analysis of taurine, anserine, carnosine and free amino acids in a cattle muscle biopsy sampleANIMAL SCIENCE JOURNAL, Issue 3 2010Mai IMANARI ABSTRACT We have established an analysis method for some free amino acids (FAAs), as well as taurine (Tau), anserine (Ans) and carnosine (Car), in a fresh biopsy sample from cattle muscle. A series of model biopsy samples, corresponding to the mixtures of lean meat, fat and connective tissue, was prepared and showed high correlation coefficients between the compound concentration and the 3-methylhistidine (3-MeHis) content derived from hydrolysis of the biopsy sample (r = 0.74,0.95, P < 0.01). Interference from blood contamination could not be neglected, because the concentration of some FAAs in blood was comparable to that in muscle. However, it was possible to control the contamination of Tau, Ans, Car, glutamic acid, glutamine, asparatic acid and alanine to less than 5.0% when the blood contamination was controlled to less than 23%. These results suggest the necessity of measuring 3-MeHis as an index of lean meat and hemoglobin as an index of blood contamination when compounds in muscle biopsy samples are evaluated. We have carried out a series of these analyses using one biopsy sample and reveal differences in Tau, Ans, Car and some FAAs in beef muscle after different feeding regimes. [source] Collective Baha'i Identity Through Embodied Persecution: "Be ye the fingers of one hand, the members of one body"ANTHROPOLOGY OF CONSCIOUSNESS, Issue 1-2 2000Curtis Humes Members of the Baha'i Faith have been subject to persecution in Iran since the mid-nineteenth century. Our investigation considers how collective identity among a Pacific Northwest Community has been constructed through the contexts of continued persecution in Iran and the development of religious texts, which helped to define the religious community. The texts found within the Baha'i Faith utilize metaphors of the body to construct religious identity. Many anthropologists have theorized on the usefulness of the body as a unit of study; in addition, recent attention by scholars has illustrated the intersection of the body and religion. A model is developed linking identity, consciousness, the body and experience that explains how collective identity is constructed. When considering the situation of the Baha'i community, this model has proven particularly useful in understanding how geographically disassociated people manage to construct social kinship within the context of religious persecution. In particular, American Baha'is describe the persecution of Baha'is in Iran as a collective experience, especially since the direct experience of persecution is far removed from their everyday living. Preliminary analysis of interviews with an American Baha'i, and an ex-patriot Iranian Baha'i reveal differences in constructions of identity. [source] Microeconometric analysis of wine grape supply contracts in Australia,AUSTRALIAN JOURNAL OF AGRICULTURAL & RESOURCE ECONOMICS, Issue 1 2005Iain Fraser This paper examines wine grape supply contracts used in the main grape growing regions of Australia. An empirical analysis provides insight into specific aspects of contract design and implementation. Statistical analyses of sample data reveal differences between regions in contract specifications. Lower quality grape growing regions place a greater reliance on grape quality assessment to determine bonus/penalty payments compared to higher quality regions. Contracts in higher quality regions place greater emphasis on explicit winery involvement and direction in vineyard management. Results indicate that longer duration contracts are more inclusive in terms of the number of clauses included. Evidence of risk shifting (i.e., winery to grower) for high quality grapes is reported, where the price received by growers is determined by the bottle price of the wine produced. [source] Anatomy and systematics of the minute syrnolopsine gastropods from Lake Tanganyika (Caenogastropoda, Cerithioidea, Paludomidae)ACTA ZOOLOGICA, Issue 4 2008Ellen E. Strong Abstract The minute syrnolopsine gastropods endemic to Lake Tanganyika have been allied to a number of freshwater, marine and terrestrial groups as a consequence of superficial conchological similarity. Although early anatomical studies confirmed the cerithioid organization of this clade, their close relationship to other lake species was not consistently recognized. In several recent cladistic analyses based on molecular data, the higher taxonomic placement and sister group relationships of syrnolopsines have been unstable. The present analysis confirms that syrnolopsines possess a spermatophore-forming organ , a synapomorphy of the Paludomidae , corroborating their placement in this family. Consistent with the molecular data, syrnolopsine monophyly is supported by two characters that occur exclusively in this group (salivary gland ducts that bypass the nerve ring and a linear albumen gland). Several characters in Martelia tanganyicensis, the most diminutive syrnolopsine , are only evident in the smallest lake species thus far investigated (Bridouxia, Stormsia) namely reduction of ctenidial leaflets, sorting area, intestine length and number of statoconia. These features are interpreted as being correlated with reduction in size. Nevertheless, close examination reveals differences in detail that allow more refined hypotheses of homology and are consistent with their independent origin. [source] SiO2 -CaO Vitreous Films Deposited onto Ti6Al4V SubstratesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 8 2003Isabel Izquierdo-Barba Abstract A sol-gel dipping method has been utilised to deposit SiO2 -CaO films onto Ti6Al4V alloy substrates. These layers were prepared by the dip-coating technique from a series of precursor solutions with different concentrations of glassy xSiO2 -(1 , x)CaO (x = 0.8 mol) diluted with absolute ethanol. The characterisation of the films by a variety of techniques reveals differences in the textural properties and in the films' thicknesses depending on the sol concentration in the precursor solution. Concentrated precursor solutions yield porous layers with a higher thickness and surface roughness than those obtained from the dilute ones. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003) [source] Structural insight into the evolutionary and pharmacologic homology of glutamate carboxypeptidases II and IIIFEBS JOURNAL, Issue 16 2009Klara Hlouchova Glutamate carboxypeptidase III (GCPIII) is a metalloenzyme that belongs to the transferrin receptor/glutamate carboxypeptidase II (GCPII; EC 3.4.17.21) superfamily. GCPIII has been studied mainly because of its evolutionary relationship to GCPII, an enzyme involved in a variety of neuropathologies and malignancies, such as glutamatergic neurotoxicity and prostate cancer. Given the potential functional and pharmacological overlap between GCPIII and GCPII, studies addressing the structural and physiological properties of GCPIII are crucial for obtaining a deeper understanding of the GCPII/GCPIII system. In the present study, we report high-resolution crystal structures of the human GCPIII ectodomain in a ,pseudo-unliganded' state and in a complex with: (a) l -glutamate (a product of hydrolysis); (b) a phosphapeptide transition state mimetic, namely (2S,3,S)-{[(3,-amino-3,-carboxy-propyl)-hydroxyphosphinoyl]methyl}-pentanedioic acid; and (c) quisqualic acid, a glutamate biostere. Our data reveal the overall fold and quaternary arrangement of the GCPIII molecule, define the architecture of the GCPIII substrate-binding cavity, and offer an experimental evidence for the presence of Zn2+ ions in the bimetallic active site. Furthermore, the structures allow us to detail interactions between the enzyme and its ligands and to characterize the functional flexibility of GCPIII, which is essential for substrate recognition. A comparison of these GCPIII structures with the equivalent GCPII complexes reveals differences in the organization of specificity pockets, in surface charge distribution, and in the occupancy of the co-catalytic zinc sites. The data presented here provide information that should prove to be essential for the structurally-aided design of GCPIII-specific inhibitors and might comprise guidelines for future comparative GCPII/GCPIII studies. [source] Characterisation of preYvaY export reveals differences in the substrate specificities of Bacillus subtilis and Escherichia coli leader peptidasesFEMS MICROBIOLOGY LETTERS, Issue 1 2003Dirk Linde Abstract Translocation, processing and secretion of YvaY, a Bacillus subtilis protein of unknown function, were characterised both in B. subtilis and in Escherichia coli. In its natural host B. subtilis, YvaY was transiently synthesised at the end of the exponential growth phase. It was efficiently secreted into the culture supernatant in spite of a calculated membrane spanning domain in the mature part of the protein. In E. coli, despite the high conservation of Sec-dependent transport components, processing of preYvaY was strongly impaired. To uncover which elements of E. coli and B. subtilis translocation systems are responsible for the observed substrate specificity, components of the B. subtilis Sec-system were co-expressed besides yvaY in E. coli. Expression of B. subtilis secA or secYEG genes did not affect processing, but expression of B. subtilis signal peptidase genes significantly enhanced processing of preYvaY in E. coli. While the major signal peptidases SipS or SipT had a strong stimulatory effect on preYvaY processing, the minor signal peptidases SipU, SipV or SipW had a far less stimulatory effect in E. coli. These results reveal that targeting and translocation of preYvaY is mediated by the E. coli Sec proteins but processing of preYvaY is not performed by E. coli signal peptidase LepB. Thus, differences in substrate specificities of E. coli LepB and the B. subtilis Sip proteins provide the bottleneck for export of YvaY in E. coli. Significant slower processing of preYvaY in absence of SecB indicated that SecB mediates targeting of the B. subtilis precursor. [source] The double vocal signature of crested penguins: is the identity coding system of rockhopper penguins Eudyptes chrysocome due to phylogeny or ecology?JOURNAL OF AVIAN BIOLOGY, Issue 5 2005Amanda Searby Parent-offspring recognition systems are used in bird colonies to avoid misdirected parental care. In penguins, where the risk of confusion is particularly high, recognition is achieved by acoustic signals that constitute highly efficient vocal signatures. Comparisons between species from the Pygoscelis and Aptenodytes genera have revealed interspecific differences on the encoding of information within the signatures which correlate with the presence/absence of nests in the colonies. However a recent study of individual recognition in macaroni penguins Eudyptes chrysolophus revealed diversity within nest-building species. This paper investigates whether the original and intermediate signature system found in macaroni penguins is shared by another species of Eudyptes, the rockhopper penguin E. chrysocome. Vocal signatures of rockhopper penguins were analysed and compared to macaroni penguins'. We used a methodology derived from the theory of information to determine which parameters of the call were likely to encode individual identity. Playbacks of modified calls in the field complemented the analyses, and parent-chick reunions were compared between the two species. Our results reveal a similar double signature system within the Eudyptes genus, which integrates information simultaneously from the temporal and spectral domains. This double encoding is made through the tempo given by the successive syllables of the call and the harmonic content of the call. While it confirms the hypothesis that signatures are simpler in nest-building species, this result reveals differences in the efficacies of signatures within this category. This suggests that other parameters such as the mean distance recognition should be considered to account for the differences in the encoding of the vocal signatures and in their resulting efficacies. [source] Coat condition of ringtailed lemurs, Lemur catta at Berenty Reserve, Madagascar: I. differences by age, sex, density and tourism, 1996,2006AMERICAN JOURNAL OF PRIMATOLOGY, Issue 3 2009Alison Jolly Abstract An index of coat condition can be a non-invasive tool for tracking health and stress at population level. Coat condition in ringtailed lemurs, Lemur catta, was recorded during September,November birth seasons of 1996, 1997, 1999, and 2001,2006 at Berenty Reserve, Madagascar. Condition was scored on a scale from 0: full, fluffy coat with guard hairs present, to 5: half or more of body hairless. Adult males did not differ overall from adult females. Coats were worse in adults than in 2-year-old subadults; 1-year-old juveniles were intermediate. Mothers and adult males lost coat condition as the season progressed: non-mother females maintained condition. Years 1999,2002 scored better coats than either 1996,1997 or 2003,2006. Lemurs in high population density areas had worse coats than in natural forest, but tourist presence had less effect than density. Monitoring coat condition in an apparently healthy population reveals differences between population segments, and in a forest fragment with limited immigration or emigration it can track progressive changes, correcting impressions of progressive improvement or degradation over time. Above all it gives a baseline for response to climate changes or eventual pathology. Am. J. Primatol. 71:191,198, 2009. © 2008 Wiley-Liss, Inc. [source] Sodium iodine(V) oxyfluoride, NaIO2F2ACTA CRYSTALLOGRAPHICA SECTION C, Issue 7 2008Jean-Paul Laval As an extension of a general structural study concerning fluorides and oxyfluorides of cations presenting a stereochemically active electronic lone pair, until now limited to tellurium(IV) phases, the previously unknown structure of NaIO2F2 corresponds to a new structure type based on isolated IO2F2, polyhedra forming sheets separated by Na+ layers. The sodium ion is octahedrally coordinated with 2/m site symmetry, while the IV atom has m2m symmetry with a stereochemically active lone electron pair. The O and F atoms (both with m symmetry) are bonded to the IV atoms in a fully ordered manner. A comparison with the structure of ferroelastic KIO2F2 and with structures based on hexagonal close packing of anions, mainly rutile-type and FeTeO3F-type, reveals differences that are attributed to the smaller ionic radius of Na+ and the ordering of the Na and I cations. [source] Spectroscopy of Hydrocarbon Grains toward the Galactic Center and Quintuplet ClusterASTRONOMISCHE NACHRICHTEN, Issue S1 2003J.E. Chiar Abstract Our view of the Galactic center (GC) is affected by extinction from both diffuse interstellar medium (ISM) dust and dense molecular clouds along the line of sight. The enormous visual extinction present toward the center of our Galaxy (,31 magnitudes) necessitates a study of the interstellar dust properties as well as an investigation into the distribution of the different dust components. We have built upon the historic spectroscopy of Willner et al. (1979), Butchart et al. (1986), and McFadzean et al. (1989) in order to investigate the distribution of these dust components across the GC field. Specifically, we employ spectroscopy in the 3 ,m region to investigate absorption features at 3.0 ,m and 3.4 ,m in lines of sight toward the GC central cluster and the Quintuplet cluster to the northeast. The 3.4 ,m feature is one of the primary spectral signatures of the organic component of interstellar dust and is, to date, only observed in the cold diffuse interstellar medium. The 3.0 ,m ice feature is carried by dense molecular cloud material, and can therefore be used to loosely trace the distribution of such material across the GC field. By obtaining spectra for multiple sightlines we have been able to deconvolve the diffuse ISM and dense molecular cloud components. Our study shows that differences exist in the spectra of relatively nearby lines of sight in the Galactic center central cluster. The depth of the 3.0 ,m water-ice feature varies by a factor of almost 5 across a 2 parsec (in projection) region, perhaps re.ecting the clumpy nature of the dense clouds. In addition, we found that the 3.4 ,m hydrocarbon feature varies in depth across the areas studied toward the central cluster, whereas the depth is relatively constant toward the Quintuplet cluster. This is likely a reflection of the distribution of extinction from the foreground diffuse ISM. Our ground-based and space-based spectroscopy reveals differences in absorption features in the 3 and 6 ,m regions between sightlines toward the GC central cluster and those toward the Quintuplet cluster. While the 3 ,m spectra of both regions show a broad absorption feature blueward of the 3.4 ,m absorption, only the Quintuplet spectra show a distinct absorption feature at 3.28 ,m. This feature is indicative of the presence of polycyclic aromatic hydrocarbons (PAHs) along the line of sight. The Quintuplet-proper sources have 6 ,m spectra that are markedly different than that of GC IRS 7 in the central cluster, and instead strongly resemble the spectra seen toward dusty late-type carbon-class (WC)Wolf-Rayet stars. This is the first hint of some spectroscopic similarity between the Quintuplet sources and dusty WC stars. [source] Structure of Staphylococcus aureus cytidine monophosphate kinase in complex with cytidine 5,-monophosphateACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 8 2006Jingshan Ren The crystal structure of Staphylococcus aureus cytidine monophosphate kinase (CMK) in complex with cytidine 5,-monophosphate (CMP) has been determined at 2.3,Å resolution. The active site reveals novel features when compared with two orthologues of known structure. Compared with the Streptococcus pneumoniae CMK solution structure of the enzyme alone, S. aureus CMK adopts a more closed conformation, with the NMP-binding domain rotating by ,16° towards the central pocket of the molecule, thereby assembling the active site. Comparing Escherichia coli and S. aureus CMK,CMP complex structures reveals differences within the active site, including a previously unreported indirect interaction of CMP with Asp33, the replacement of a serine residue involved in the binding of CDP by Ala12 in S. aureus CMK and an additional sulfate ion in the E. coli CMK active site. The detailed understanding of the stereochemistry of CMP binding to CMK will assist in the design of novel inhibitors of the enzyme. Inhibitors are required to treat the widespread hospital infection methicillin-resistant S. aureus (MRSA), currently a major public health concern. 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