Distinct genomic sequence of the CNR/Pcdhalpha genes in chicken

CNR/Pcdhalpha family proteins have been first identified as a receptor family that corporate with Fyn, a family of the Src family of tyrosine kinase, and known as synaptic cadherins. Here we report the complete genomic sequence and organization of the chicken (Gallus gallus) CNR/Pcdhalpha The total length of chicken CNR/Pcdhalpha is 177kb. The chicken CNR/Pcdhalpha cluster encodes 12 variable and 3 constant exons. The genomic organizations of the chicken, rat, mouse, and human CNR/Pcdhalpha are basically orthologous. The constant-region exons (CP1, CP2, and CP3) are highly conserved between chicken and mammals, with percent identities of 90.9%, 90.7%, and 91.8% at the amino-acid level for chicken versus rat, mouse, and human, respectively. In contrast, the percent identities of the variable-region exons between chicken and mammals were lower: 51.8%, 51.3%, and 52.7%, on average, for chicken versus rat, mouse, and human, respectively, at the amino-acid level. Moreover, the chicken variable-region exons (from v1 to v12) are highly conserved paralogously (91.4%: nucleic acid, 92.4%: amino acid) in comparison with those of mammals. The CG content of each variable exon in the chicken (v1 to v12) is 74% on average and the CpG dinucleotide frequency in each variable-region exon is twice that of mammals. Due to the high CG content, chicken variable exons (from v1 to v12) encode 3 to 4 frame-shifted open reading frames, which span 1.5-3.0kb, in both the sense and anti-sense orientations.     

Involvement of caspase-9 in execution of the maternal program of apoptosis in Xenopus late blastulae overexpressed with S-adenosylmethionine decarboxylase

We previously demonstrated that overexpression of S-adenosylmethionine decarboxylase (SAMDC) in Xenopus early embryos induces execution of maternal program of apoptosis shortly after midblastula transition, which likely serves as a fail-safe mechanism of early development to eliminate physiologically damaged cells before they entering the gastrula stage. To determine how caspases are involved in this process, we microinjected peptide inhibitors and "dominant-negative forms" of caspase-9 and -1 into Xenopus fertilized eggs, and found that inhibitors of caspase-9, but not caspase-1, completely suppress SAMDC-induced apoptosis. The lysate of SAMDC-overexpressing late blastulae contained activity to cleave in vitro-synthesized [(35)S]procaspase-9, but not [(35)S]procaspase-1, and mRNA for caspase-9, but not caspase-1, occurred abundantly in the unfertilized egg as maternal mRNA. We also found that overexpression of caspase-9 and -1 equally executes the apoptosis, but the apoptosis executed by these mRNAs was only partially rescued by Bcl-2 and rescued embryos did not develop beyond neurula stage. These results indicate that activation of caspase-9 is a key step for execution of the maternally preset program of apoptosis in Xenopus early embryos.     

An introduction to the short-term toxicology of respirable industrial fibres

Fibrous materials, exemplified by asbestos, that release respirable fibres are in common use and there is considerable knowledge regarding the toxicology of these common fibres. Newer materials or those that are under development, such as synthetic organic fibres and carbon nanotubes may have a different toxicology paradigms. The existing paradigm for silicate fibres suggests that respirable fibre types vary in their ability to cause lung disease and that this can be understood on the basis of the length of the fibres and their biopersistence in the lungs. Because fibres are regulated on a fibre number basis and the hazard is understood on the basis of the number of long fibres, in fibre testing the dose should always be expressed as fibre number, not mass and the length and diameter distribution need to be known. Short-term biological tests are likely to produce false positives in the case of long non-biopersistent fibres, because whilst they may have effects in vitro, they do not persist long enough in the lungs for sufficient dose to build up and produce effects in vivo. The biopersistence of fibres is therefore a key factor that needs to be known in order to interpret short-term tests that may claim to predict fibre pathogenicity.     

Differential Expression of Immune Response Genes in Steller Sea Lions (Eumetopias jubatus): An Indicator of Ecosystem Health?

Characterization of the polygenic and polymorphic features of the Steller sea lion major histocompatibility complex (MHC) provides an ideal window for evaluating immunologic vigor of the population and identifying emergence of new genotypes that reflect ecosystem pressures. MHC genotyping can be used to measure the potential immunologic vigor of a population. However, since ecosystem-induced changes to MHC genotype can be slow to emerge, measurement of differential expression of these genes can potentially provide real-time evidence of immunologic perturbations. MHC DRB genes were cloned and sequenced using peripheral blood mononuclear leukocytes derived from 10 Steller sea lions from Southeast Alaska, Prince William Sound, and the Aleutian Islands. Nine unique DRB gene sequences were represented in each of 10 animals. MHC DRB gene expression was measured in a subset of six sea lions. Although DRB in genomic DNA was identical in all individuals, relative levels of expressed DRB mRNA was highly variable. Selective suppression of MHC DRB genes could be indicative of geographically disparate environmental pressures, thereby serving as an immediate and sensitive indicator of population and ecosystem health.     

PRISM: a data management system for high-throughput proteomics

Advanced proteomic research efforts involving areas such as systems biology or biomarker discovery are enabled by the use of high level informatics tools that allow the effective analysis of large quantities of differing types of data originating from various studies. Performing such analyses on a large scale is not feasible without a computational platform that performs data processing and management tasks. Such a platform must be able to provide high-throughput operation while having sufficient flexibility to accommodate evolving data analysis tools and methodologies. The Proteomics Research Information Storage and Management system (PRISM) provides a platform that serves the needs of the accurate mass and time tag approach developed at Pacific Northwest National Laboratory. PRISM incorporates a diverse set of analysis tools and allows a wide range of operations to be incorporated by using a state machine that is accessible to independent, distributed computational nodes. The system has scaled well as data volume has increased over several years, while allowing adaptability for incorporating new and improved data analysis tools for more effective proteomics research.     

3-(2-Aminocarbonylphenyl)propanoic acid analogs as potent and selective EP3 receptor antagonists. Part 1: Discovery and exploration of the carboxyamide side chain

A series of 3-(2-aminocarbonyl-4-phenoxymethylphenyl)propanoic acid analogs were synthesized and evaluated for their EP3 antagonist activity in the presence of additive serum albumin. Several compounds were biologically evaluated for their in vivo efficacy with respect to the PGE₂-induced uterine contraction in pregnant rats as well as their pharmacokinetics. The discovery process of these potent and selective EP3 antagonists and their structure activity relationship are also presented.     

Altered cardiac metabolic phenotype after prolonged inhibition of NO synthesis in chronically instrumented dogs

Acute inhibition of nitric oxide (NO) synthase causes a reversible alteration in myocardial substrate metabolism. We tested the hypothesis that prolonged NO synthase inhibition alters cardiac metabolic phenotype. Seven chronically instrumented dogs were treated with N(omega)-nitro-L-arginine methyl ester (L-NAME, 35 mg.kg(-1).day(-1) po) for 10 days to inhibit NO synthesis, and seven were used as controls. Cardiac free fatty acid, glucose, and lactate oxidation were measured by infusion of [(3)H]oleate, [(14)C]glucose, and [(13)C]lactate, respectively. After 10 days of L-NAME administration, despite no differences in left ventricular afterload, cardiac O(2) consumption was significantly increased by 30%, consistent with a marked enhancement in baseline oxidation of glucose (6.9 +/- 2.0 vs. 1.7 +/- 0.5 micromol.min(-1).100 g(-1), P < 0.05 vs. control) and lactate (21.6 +/- 5.6 vs. 11.8 +/- 2.6 micromol.min(-1).100 g(-1), P < 0.05 vs. control). When left ventricular afterload was increased by ANG II infusion to stimulate myocardial metabolism, glucose oxidation was augmented further in the L-NAME than in the control group, whereas free fatty acid oxidation decreased. Exogenous NO (diethylamine nonoate, 0.01 micromol.kg(-1).min(-1) iv) could not reverse this metabolic alteration. Consistent with the accelerated rate of carbohydrate oxidation, total myocardial pyruvate dehydrogenase activity and protein expression were higher (38 and 34%, respectively) in the L-NAME than in the control group. Also, protein expression of the constitutively active glucose transporter GLUT-1 was significantly elevated (46%) vs. control. We conclude that prolonged NO deficiency causes a profound alteration in cardiac metabolic phenotype, characterized by selective potentiation of carbohydrate oxidation, that cannot be reversed by a short-term infusion of exogenous NO. This phenomenon may constitute an adaptive mechanism to counterbalance cardiac mechanical inefficiency.