bluuebunny/crossref_metadata_2025_split huggingface dataset:
HOPF–CYCLIC HOMOLOGY AND RELATIVE CYCLIC HOMOLOGY OF HOPF–GALOIS EXTENSIONS
Authors: JARA P. , ŞTEFAN D. 
Published: June 2006

Let $H$ be a Hopf algebra and let $\mathcal{M}_s (H)$ be the category of all left $H$-modules and right $H$-comodules satisfying appropriate compatibility relations. An object in $\mathcal{M}_s (H)$ will be called a stable anti-Yetter–Drinfeld module (over $H$) or a SAYD module, for short. To each $M \in \mathcal{M}_s (H)$ we associate, in a functorial way, a cyclic object $\mathrm{Z}_\ast (H, M)$. We show that our construction can be used to compute the cyclic homology of the underlying algebra structure of $H$ and the relative cyclic homology of $H$-Galois extensions.Let $K$ be a Hopf subalgebra of $H$. For an arbitrary $M \in \mathcal{M}_s (K)$ we define a right $H$-comodule structure on $\mathrm{Ind}_K^H M := H \otimes_K M$ so that $\mathrm{Ind}_K^H M$ becomes an object in $\mathcal{M}_s (H)$. Under some assumptions on $K$ and $M$ we compute the cyclic homology of $\mathrm{Z}_\ast (H, \mathrm{Ind}_K^H M)$. As a direct application of this result, we describe the relative cyclic homology of strongly graded algebras. In particular, we calculate the cyclic homology of group algebras and quantum tori.Finally, when $H$ is the enveloping algebra of a Lie algebra $\mathfrak{g}$, we construct a spectral sequence that converges to the cyclic homology of $H$ with coefficients in a given SAYD module $M$. We also show that the cyclic homology of almost symmetric algebras is isomorphic to the cyclic homology of $H$ with coefficients in a certain SAYD module.
Therapeutic potential of RNA interference against cancer
Authors: Takeshita Fumitaka , Ochiya Takahiro 
Published: June 2006

One of the most dramatic events of the past 5 years in the field of molecular biology has been the discovery of RNA interference (RNAi). Although RNAi is an evolutionarily conserved phenomenon for sequence‐specific gene silencing in mammalian cells, exogenous small interfering RNA (siRNA) and vector‐based short hairpin RNA (shRNA) can also invoke RNAi responses. Both are now not only experimental tools for analyzing gene function but are expected to be excellent avenues for drug target discovery and the emerging class of gene medicine for targeting incurable diseases such as cancer. The success of cancer therapeutic use of RNAi relies on the development of safe and efficacious delivery systems that introduce siRNA and shRNA expression vectors into target tumor cells. For their delivery, a variety of strategies have been used, most of them based on traditional gene therapy delivery systems. In this review, we present siRNA delivery method strategies and discuss the potential of RNAi‐based gene therapy in cancer treatment. (Cancer Sci 2006; 97: 689–696)
The role of ecological interactions on the physiological flexibility of lizards
Authors: NAYA D. E. , BOŽINOVIĆ F. 
Published: June 2006

Summary

An organism's ability to adjust its physiological traits to changes in environmental conditions is central for its ecological success. However, the effect of ecological interactions on physiological flexibility has rarely been investigated. Here we carry out a factorial experiment to analyse how food limitation (a potential result of competition) and tail loss (a potential result of sub‐lethal predation) affect anatomical and physiological traits of the South American lizard Liolaemus nitidus.
The size of several internal organs was affected by food availability. Small intestine mass increased with food consumption, allowing animals to keep constant digestibility at greater levels of digesta, which in turn permitted higher rates of food assimilation. Organs related to energy storage reached larger sizes in autotomized animals with high food availability, but tail regeneration rate after 3 weeks did not change with food availability.
Metabolic rate was affected by tail loss, and animals regenerating their tail showed higher metabolic rates than tailed ones. Because this increase in metabolic rate was independent of internal organ mass, a local effect of tail regeneration process (e.g. cell proliferation) on metabolic rate is suggested.
When anatomical and metabolic data are jointly considered it follows that lizards adopt different physiological strategies, changing both energetic inputs and expenditures. This fact illustrates the complex interplay between ecological factors and physiological flexibility, which ultimately determine an organism's fitness.
Unravelling first‐generation pedigrees in wild endangered salmon populations using molecular genetic markers
Authors: HERBINGER C. M. , O’REILLY P. T. , VERSPOOR E. 
Published: June 2006

AbstractThere is increasing interest in the use of molecular genetic data to infer genealogical relationships among individuals in the absence of parental information. Such analyses can provide insight into mating systems and estimations of heritability in the wild. In addition, accurate pedigree reconstruction among the founders of endangered populations being reared in captivity would be invaluable. Many breeding programs for endangered species attempt to minimize loss of genetic variation and inbreeding through strategies designed to minimize global co‐ancestry, but they assume a lack of relatedness among the founders. Yet populations that are the target of such programs are generally in serious demographic decline, and many of the available founders may be closely related. Here we demonstrate determination of full and half‐sib relationships among the wild founders of a captive breeding program involving two endangered Atlantic salmon populations using two different approaches and associated software, pedigree and colony. A large portion of the juveniles collected in these two rivers appear to be derived from surprisingly few females mating with a large number of males, probably small precocious parr. Another group of potential founders, obtained from a local hatchery, clearly originated from a small number of full‐sib crosses. These results allowed us to prioritize individuals on the basis of conservation value, and are expected to help minimize loss of genetic variation through time. In addition, insight is provided into the number of contributing parents and the mating systems that produced this last generation of endangered wild Atlantic salmon.
How female reed buntings benefit from extra‐pair mating behaviour: testing hypotheses through patterns of paternity in sequential broods
Authors: BOUWMAN KAREN M. , BURKE TERRY , KOMDEUR JAN 
Published: June 2006

AbstractExtra‐pair paternity is an important aspect of reproductive strategies in many species of birds. Given that in most species females control whether fertilization occurs, they are expected to benefit in some way from the extra‐pair matings. In this study we use patterns of extra‐pair paternity (EPP) in broods of individual reed buntings (Emberiza schoeniclus), both within and between seasons, to test four hypothesized female benefits: (1) assessing potential future partners and seeking (2) genetic diversity (3) good genes, or (4) compatible genes. Reed buntings are socially monogamous, multibrooded passerines with extremely high levels of extra‐pair paternity. We studied a population of reed buntings in the Netherlands in 2002 and 2003; 51% of offspring in 74% of nests were extra‐pair. We showed that patterns of EPP did not support the first and second hypotheses, since females did not form a pair with previous extra‐pair partners, EPP was not evenly distributed among broods and more broods than expected were sired by a single male. Furthermore, there was no relation between a male's within‐ and extra‐pair fertilization success, no consistency in EPP between breeding attempts, no effect of parental relatedness on EPP and several cases of reciprocal paternity. These patterns do not support the good genes hypothesis and are most consistent with the genetic compatibility hypothesis. However, our previous finding that older males are more successful in gaining EPP, suggests some effect of good genes. These hypotheses need not be mutually exclusive, as females may select compatible males above a certain quality threshold (e.g. old males).
MMP‐1 promoter gene polymorphism and susceptibility to chronic periodontitis in a Chinese population
Authors: Cao Z. , Li C. , Zhu G. 
Published: June 2006

AbstractA single nucleotide polymorphism in the promoter region of −1607 bp of the human MMP‐1 gene has been found to be associated with an increased risk of various inflammatory diseases and cancer metastasis. This study aimed to evaluate the association between the MMP‐1 promoter gene polymorphism and chronic periodontitis susceptibility and/or severity in a Chinese population. Genomic DNA was obtained from whole blood samples in 60 Chinese subjects with chronic periodontitis and 50 periodontally healthy subjects as controls. MMP‐1 promoter fragment was amplified by polymerase chain reaction, and the polymorphism was analyzed by restriction endonuclease cleavage. In the control subjects, the 2G allele was observed a frequency of 49%, while in severely diseased patients, the 2G allele was seen in 73.4%. The individuals with the 2G allele seem to be approximately three times at greater risk for developing the severe chronic periodontitis (χ2 = 12.148, P = 0.000). The genotype of 2G/2G was found in 58.5% of the severe periodontitis and 24% of the control group (χ2 = 11.779, P = 0.003). This study suggests that a single nucleotide polymorphism in the MMP‐1 promoter region of −1607 bp may be associated with severe chronic periodontitis in a Chinese population.
Low‐cost, simultaneous, single‐sequence genotyping of the HLA‐A, HLA‐B and HLA‐C loci
Authors: Abbott W. G. H. , Tukuitonga C. F. , Ofanoa M. , Munn S. R. , Gane E. J. 
Published: June 2006

AbstractNew automated DNA sequencing technology has enabled the development of an assay for genotyping the three major HLA class 1 loci from a single sequence of each gene containing exon 3, intron 2 and exon 2. The assay allows 31 subjects (with 3 negative controls) to be genotyped at all three loci simultaneously, using a 96‐well plate format. Genotypes were assigned by comparing each sequence to a database of 307 HLA‐A, 563 HLA‐B and 166 HLA‐C alleles. Unequivocal, 4‐digit allele assignments were made for 40 of 130 HLA‐A genes, 82 of 130 HLA‐B genes and 97 of 130 HLA‐C genes from 21 European, 20 Tongan and 24 Niuean subjects. Ambiguity in interpretation of the sequence contributed to 66 of the 170 equivocal allele assignments, and 105 equivocal assignments were due to polymorphisms outside exons 2 and 3. All known alternative interpretations of ambiguous genotypes were identified, and seven HLA‐B and two HLA‐C ambiguities were resolved by reading the out‐of‐phase exon 2 sequence that followed an indel in intron 2. The genotypes of a subgroup of 27 heterozygous subjects, whose genotypes contained all of the alleles identified in this study, were confirmed with commercial, generic PCR‐SSP typing. In European subjects, the repertoire of HLA‐B/HLA‐C haplotypes was almost identical to previously published data. We identified five new HLA‐B/HLA‐C haplotypes in the Polynesian subjects, and the remaining haplotypes were of Asian origin. In summary, we are describing a low‐cost, sequencing assay for the three major HLA class I loci that provides a level of resolution that is comparable with a commercial PCR‐SSP assay.
Long‐term cultured neonatal porcine islet cell monolayers: a potential tissue source for transplant in diabetes
Authors: Mancuso Francesca , Basta Giuseppe , Calvitti Mario , Luca Giovanni , Guido Lucia , Racanicchi Leda , Montanucci Pia , Becchetti Ennio , Calafiore Riccardo 
Published: June 2006

Abstract:  Background:  The restricted availability of cadaveric human donor pancreases mandates validation of possibly inexhaustible, alternative sources of insulin secretory cells in order to expand islet transplant for the therapy of insulin dependent diabetes mellitus (T1DM).Methods:  Neonatal pig pancreatic islets (NPI), isolated and purified by our method, were specially cultured until confluent cell monolayers were obtained. Expression of several β‐cell phenotype transcriptional factors, under glucose and other stimuli, were examined throughout 90 days of culture.Results:  High glucose concentration and glucagon‐like peptide 1 (GLP‐1) were associated with maintenance either of insulin secretory patterns from the incubated cell monolayers, or expression of transcriptional markers associated with β‐cell like phenotypes.Conclusion:  Morphological and molecular expression of β‐cell markers and products from NPI cell monolayers seem to identify a novel and potentially powerful source of insulin producing cells that might fulfill transplant needs for insulin substitution therapy
Molecular interactions between porcine and human gammaherpesviruses: implications for xenografts?
Authors: Santoni Fabio , Lindner Iris , Caselli Elisabetta , Goltz Michael , Luca Dario Di , Ehlers Bernhard 
Published: June 2006

Abstract:  Background:  Reactivation of latent herpesviruses is an important cause of morbidity and mortality in human transplantation. This issue might be further complicated in the case of xenotransplantation. Zoonotic viruses could reactivate and replicate in the transplanted tissue, and interactions with homologous human viruses could take place. Since the pig is a favoured animal as donor of organs for human transplants, we analysed the possibility of interactions between porcine and human herpesviruses. Porcine lymphotropic herpesvirus 1 (PLHV‐1) is a gammaherpesvirus homologous to Epstein–Barr virus (EBV) and to human herpesvirus 8 (HHV‐8), is highly prevalent in pigs and is associated to lymphoproliferative disease in immunosuppressed and transplanted miniature swine.Methods:  The main viral transactivators of PLHV‐1, ORF50, ORF57, ORFA6/BZLF1h, were cloned and tested for their transactivating ability on several EBV and HHV‐8 promoters using reporter assays. Also the effects of HHV‐8 ORF50, ORF57 and ORFK8 and EBV BRLF1/ R‐transactivator (Rta) and BZLF1/ Z‐transactivator (Zta) on PLHV‐1 lytic promoters were analysed.Results:  Porcine lymphotropic herpesvirus 1 ORF50 upregulated all HHV‐8 promoters and PLHV‐1 ORFA6/BZLF1h transactivated EBV promoters. Furthermore, transfection of PLHV‐1 ORF50 into BC‐3 cells, latently infected with HHV‐8, resulted in HHV‐8 reactivation. Likewise, HHV‐8 ORF50 and EBV BRLF1/Rta had a strong transactivating effect on PLHV‐1 promoters. Also EBV BZLF1/Zta and HHV‐8 ORF57 induced PLHV‐1 transactivation, but at lower levels.Conclusion:  The results suggest that reciprocal molecular interactions between human and porcine herpesviruses might occur in vivo, and support the hypothesis that PLHV‐1 might have pathogenic relevance in the course of xenotransplantation.
Health status of transgenic pigs expressing the human complement regulatory protein CD59
Authors: Deppenmeier Stefanie , Bock Oliver , Mengel Michael , Niemann Heiner , Kues Wilfried , Lemme Erika , Wirth Dagmar , Wonigeit Kurt , Kreipe Hans 
Published: June 2006

Abstract:  Background:  Microinjection of foreign DNA into pronuclei of zygotes has been the method of choice for the production of transgenic domestic animals. Following microinjection the transgene is randomly integrated into the host genome which can be associated with insertional mutagenesis and unwanted pathological side effects.Methods:  Here, we evaluated the health status of pigs transgenic for the human regulator of complement activation (RCA) CD59 and conducted a complete pathomorphological examination on 19 RCA transgenic pigs at 1 to 32 months of age from nine transgenic lines. Nine wild‐type animals served as controls. Expression levels of human complement regulator CD59 (hCD59) mRNA were measured by RT‐PCR and distribution of hCD59 protein was determined by immunohistochemistry.Results:  Albeit variable transgene expression levels, no specific pathomorphologic phenotype associated with the presence of the transgene in all analyzed pig lines could be detected.Conclusions:  Transgenic expression of this human RCA gene construct is not correlated with a specific pathological phenotype in pigs. This is crucial for the application of the technology and the use of transgenic pigs for biomedical and agricultural applications.
Colour forms of Amazonian cichlid fish represent reproductively isolated species
Authors: Ready J. S. , Sampaio I. , Schneider H. , Vinson C. , Dos Santos T. , Turner G. F. 
Published: June 2006

Abstract
Laboratory mate choice experiments have confirmed species status for cichlid fish in the African Great Lakes that differ in colour and little else. Colour differences between allopatric populations of the South American cichlid genus Apistogramma are known for many species, yet the status of such populations has not been previously tested. Analysis of the genetic relationships and mate choice characteristics of populations previously described as Apistogramma caetei from eastern Amazonia indicates genetic differentiation into at least three allopatric lineages, which also show strong prezygotic isolation through female mate choice, confirming them as Biological species. If future studies confirm that this result is indicative of a general trend, the species richness of the South American cichlid fishes may presently be seriously underestimated.
Alveolata histone-like proteins have different evolutionary origins
Authors: Chan Y. H. , Kwok Alvin C. M. , Tsang Jimmy S. H. , Wong Joseph T. Y. 
Published: June 2006

Abstract
Prokaryotic histone-like proteins (Hlps) are abundant proteins found in bacterial and plastid nucleoids. Hlps are also found in the eukaryotic dinoflagellates and the apicomplexans, two major lineages of the Alveolata. It may be expected that Hlps of both groups were derived from the same ancestral Alveolates. However, our phylogenetic analyses suggest different origins for the dinoflagellate and the apicomplexan Hlps. The apicomplexan Hlps are affiliated with the cyanobacteria and probably originated from Hlps of the plastid genome. The dinoflagellate Hlps and the proteobacterial long Hlps form a clade that branch off from the node with the proteobacterial short Hlps.
Premating Avoidance of Inbreeding Absent in Female Guppies (Poecilia reticulata)
Authors: Viken Åslaug , Fleming Ian A. , Rosenqvist Gunilla 
Published: June 2006

AbstractThe recognition and avoidance of kin during mating can be an important means of reducing the potential for inbreeding depression in offspring. We report here that premating mechanisms to avoid inbreeding, either innate or learnt through juvenile experience, are at best weak in female guppies (Poecilia reticulata). Guppies are small, ovoviviparous, neo‐tropical freshwater fish, with a polygamous mating system where males actively court females and females are selective of their mates. In a series of mate‐choice experiments, naïve, virgin females of the Quare River population in Trinidad were given a choice between a brother and a non‐sib male from the same population. Initially, females were only provided olfactory cues upon which to base their choice and then subsequently both olfactory and visual cues. Despite the females displaying mate choice, we found no evidence of them discriminating between the male types in either experiment. There was thus no indication of inbreeding avoidance, suggesting that experiences after maturation or with mature males (e.g. rare male preference), dispersal and/or post‐mating mechanisms may be evolutionarily more important avoidance mechanisms.
Emx2 in the developing hippocampal fissure region
Authors: Zhao Tianyu , Kraemer Nadine , Oldekamp Judit , Çankaya Murat , Szabó Nora , Conrad Sabine , Skutella Thomas , Alvarez‐Bolado Gonzalo 
Published: June 2006

AbstractMice deficient in transcription factor gene Emx2 show developmental alterations in the hippocampal dentate gyrus. Emx2, however, is also expressed in the region around the developing hippocampal fissure. The developing fissure contains a radial glial scaffolding, and is surrounded by the outer marginal zone and the dentate marginal zone, which become specifically colonized by neurons and differentiate into stratum lacunosum‐moleculare and molecular layer of the dentate, respectively. In this study we show that the Emx2 mutant lacks the glial scaffolding of the fissure and has an outer marginal zone (precursor of the stratum lacunosum‐moleculare), as well as a dentate marginal zone severely reduced in size while most of the reelin (Reln)‐expressing cells that should occupy it fail to be generated. We have also identified a subpopulation of hippocampal Reln‐expressing cells of the marginal zone, probably born in the hem, expressing a specific combination of markers, and for which Emx2 is not essentially required. Additionally, we show differential mutant phenotypes of both Emx2 and Pax6 in neocortical vs. hippocampal Reln‐expressing cells, indicating differential development of both subpopulations.
P2Y1 and P2X7 receptors induce calcium/calmodulin‐dependent protein kinase II phosphorylation in cerebellar granule neurons
Authors: León David , Hervás Cristina , Miras‐Portugal M. Teresa 
Published: June 2006

AbstractThe activation of nucleotide receptors − both ionotropic, P2X, and most of metabotropic, P2Y − increases intracellular calcium concentration, resulting in calcium/calmodulin‐dependent protein kinase II (CaMKII) activation. Stimulation of cerebellar granule neurons in culture − with different P2X and P2Y agonists and their effect on CaMKII phosphorylation − was studied using immunocytochemical and microfluorimetrical techniques. P2X agonist: 2′‐3′‐o‐(4‐benzoylbenzoyl)‐adenosine 5′‐triphosphate (BzATP), α,β‐methylene adenosine 5′‐triphosphate (α,β‐meATP) and diadenosine pentaphosphate (Ap5A); and P2Y agonists: 2‐(methylthyo)‐adenosine diphosphate (2MeSADP) and uridine 5′‐bisphosphate (UDP); tested induced a CaMKII phosphorylation but with a different immunostaining pattern in each group. Stimulation with 2MeSADP induced a Ca2+ release from intracellular stores and a significant CaMKII phosphorylation in cell somas and neurites. This agrees with the subcellular distribution of P2Y1. MRS 2179, a specific P2Y1 inhibitor, antagonized the 2MeSADP effect. On the other hand, cerebellar granule neuron stimulation with BzATP, in Mg2+‐free conditions, produced extracellular calcium entrance and, as a result, a significant increase in CaMKII phosphorylation mostly in fibres, which correspond with P2X7 subdistribution. Immunocytochemical and microfluorimetrical experiments, using Zn2+ and Brilliant Blue G (BBG), as a specific P2X7 antagonist, confirmed that BzATP was acting through the P2X7 receptor. These results indicate that P2Y1 and P2X7 produce a significant increase in CaMKII phosphorylation, but show important differences in subcellular distribution and in effect duration. P2X7 activation in granule neurons is not associated with pore formation, according to the absence of YO‐PRO‐1 fluorescence. The abundant presence of P2X7 at the synaptic structures suggests a relevant role played by this receptor in synaptic plasticity.