Estimating the frequency of Asian cytochrome B haplotypes in standard European and local Spanish pig breeds

Mitochondrial DNA has been widely used to perform phylogenetic studies in different animal species. In pigs, genetic variability at the cytochrome B gene and the D-loop region has been used as a tool to dissect the genetic relationships between different breeds and populations. In this work, we analysed four SNP at the cytochrome B gene to infer the Asian (A1 and A2 haplotypes) or European (E1 and E2 haplotypes) origins of several European standard and local pig breeds. We found a mixture of Asian and European haplotypes in the Canarian Black pig (E1, A1 and A2), German Piétrain (E1, A1 and A2), Belgian Piétrain (E1, A1), Large White (E1 and A1) and Landrace (E1 and A1) breeds. In contrast, the Iberian (Guadyerbas, Ervideira, Caldeira, Campanario, Puebla and Torbiscal strains) and the Majorcan Black pig breeds only displayed the E1 haplotype. Our results show that the introgression of Chinese pig breeds affected most of the major European standard breeds, which harbour Asian haplotypes at diverse frequencies (15–56%). In contrast, isolated local Spanish breeds, such as the Iberian and Majorcan Black pig, only display European cytochrome B haplotypes, a feature that evidences that they were not crossed with other Chinese or European commercial populations. These findings illustrate how geographical confinement spared several local Spanish breeds from the extensive introgression event that took place during the 18th and 19th centuries in Europe.     

Butyrophenone analogues in the carbazole series: Synthesis and determination of affinities at D2 and 5-HT2A receptors

We describe a practical and efficient route for synthesis of 2-aminomethyl-1,2,3,9-tetrahydro-4H-carbazol-4-ones using an effective Fisher indole methodology. The most active compounds, 4b (QF 2003B) and 4c (QF 2004B), with pKi (5-HT_2A/D₂) ratio of 1.28 show an antipsychotic profile according to Meltzer's classification.     

1,3-Dialkyl-8-(hetero)aryl-9-OH-9-deazaxanthines as potent A2B adenosine receptor antagonists: design, synthesis, structure-affinity and structure-selectivity relationships

A number of 1,3-dialkyl-8-(hetero)aryl-9-OH-9-deazaxanthines were prepared and evaluated as ligands of recombinant human adenosine receptors (hARs). Several 1,3-dipropyl derivatives endowed with nanomolar binding affinity at hA(2B) receptors, but poor selectivity over hA(2A), hA(1) and hA(3) AR subtypes were identified. A comparison with the corresponding 7-OH- and 7,9-unsubstituted-deazaxanthines revealed that 9-OH-9-deazaxanthines are more potent hA(2B) ligands with lower partition coefficients and higher water solubility compared to the other two congeneric classes of deazaxanthines. An optimization of the para-substituent of the 8-phenyl ring of 9-OH-9-deazaxanthines led to the discovery of compound 38, which exhibited outstanding hA(2B) affinity (Ki=1.0 nM), good selectivity over hA(2A), hA(1) and hA(3) (selectivity indices=100, 79 and 1290, respectively) and excellent antagonist potency in a functional assay on rat A(2B) (pA(2B)=9.33).     

Candida albicans Mds3p,a conserved regulator of pH responses and virulence identified through insertional mutagenesis

Candida albicans is a commensal fungus that causes diverse infections after antibiotic use or immune debilitation. Gene discovery has been limited because the organism is an asexual diploid. We have developed a strategy that yields random homozygous insertion mutants. The strategy has permitted identification of several prospective essential genes. Many of these genes are homologous to nonessential Saccharomyces cerevisiae genes, and some have no S. cerevisiae homolog. These findings may expand the range of antifungal drug targets. We have also identified new genes required for pH-dependent filamentation, a trait previously associated with virulence. One newly identified gene, MDS3, is required for expression in alkaline media of two filamentation-associated genes, HWP1 and ECE1, but is not required for expression of other pH-response genes. In S. cerevisiae, the two MDS3 homologs are required for growth in alkaline media, thus arguing that Mds3p function in adaptation to external pH changes is conserved. Epistasis tests show that Mds3p contributes to virulence and alkaline pH responses independently of the well-characterized Rim101p pH-response pathway.     

Meiotic analysis of four cross-pollinated generations in a synthetic autotetraploid population of husk tomato (<i>Physalis ixocarpa</i>)

The cultivated husk tomato (Physalis ixocarpa) (2n = 2x = 24) is native from Mexico and Central America and shows a wide genetic variation. Presently, it is the fourth horticultural crop in cultivation surface in Mexico. The working team of this research previously developed an autotetraploid population by using colchicine. The objectives of the present work were to analyze the ploidy level and meiotic behavior of the subsequent generations (C3, C4, C5, C6) from the original (C2) composed only by plants with the duplicated genome from the Rendidora cultivar, and to determine pollen viability. As a diploid control the cultivar Rendidora of P. ixocarpa was used. Ploidy level was determined by flow citometry and meiotic analysis. For the meiotic study, the microsporocytes were prepared by the squash method, stained with carmin and analyzed in diakinesis. Pollen viability was evaluated through 0.01% Buffalo Black staining. The tetraploid condition prevailed through four cross-pollinating generations, maintaining a constant chromosome number 2n = 4x = 48. In diakinesis, the chromosomes of the diploid cultivar were associated into bivalents, whereas in tetraploid plants the chromosomes associated into univalents, bivalents and trivalents. Highly significant differences in bivalent pairing were detected between autotetraploid plants and between generations. Pollen viability did not show significant differences between generations and allowed reproduction. These results indicate that it is possible to develop an autotetraploid cultivar, because the polyploid state is naturally maintained and the plants are fertile. Furthermore, given the differences in bivalent pairing between plants and generations, a response to selection toward meiotic stability is expected.     

Constitutive and blood meal-induced trypsin genes in Lutzomyia longipalpis

Trypsins constitute some of the most abundant midgut digestive proteases expressed by hematophagous insects upon blood feeding. In addition to their role in the digestion of the blood meal, these proteases also have been implicated in the ability of certain pathogens to infect their natural vector. In sand flies, digestive proteases including trypsins were associated with early killing of Leishmania and are believed to play a role in the species-specificity dictating sand fly vectorial capacity. Our group is involved in studies of midgut digestive proteases in the sand fly Lutzomyia longipalpis, the principal vector of visceral leishmaniasis in Brazil. Here we report on the identification of two cDNAs, Lltryp1 and Lltryp2, which code for putative midgut trypsins in L. longipalpis. Analyses of RNA abundance using semi-quantitative RT-PCR show a different pattern of expression between the two genes. Lltryp1 expression remains undetected until blood feeding and reaches a peak at 12 h post-blood meal (PBM), returning to pre-blood meal levels at 72 h PBM. Additionally, Lltryp1 expression is undetected during larval development. Lltryp2, on the other hand, is constitutively expressed as high levels in the non-blood fed female, but is reduced upon blood feeding. At the end of the digestive cycle, Lltryp2 regains its pre-blood meal levels. This cDNA also is present in all developmental stages and in adult males. This pattern of expression is reminiscent of what is seen in mosquitoes and Old World sand flies, but has characteristics that are unique to L. longipalpis.     

Synthesis and binding affinity of novel 3-aminoethyl-1-tetralones, potential atypical antipsychotics

A series of 3-aminoethyl-1-tetralones, conformationally constrained higher homologues of haloperidol (standard for typical antipsychotic profile), have been obtained by a four-step route from valerolactone. Their binding affinities at dopamine D(2) and serotonin 5-HT2A and 5-HT2C receptors were determined, showing in some cases an atypical antipsychotic profile.     

Ovine pedomics: the first study of the ovine foot 16S rRNA-based microbiome

We report the first study of the bacterial microbiome of ovine interdigital skin based on 16S rRNA by pyrosequencing and conventional cloning with Sanger-sequencing. Three flocks were selected, one a flock with no signs of footrot or interdigital dermatitis, a second flock with interdigital dermatitis alone and a third flock with both interdigital dermatitis and footrot. The sheep were classified as having either healthy interdigital skin (H) and interdigital dermatitis (ID) or virulent footrot (VFR). The ovine interdigital skin bacterial community varied significantly by flock and clinical condition. The diversity and richness of operational taxonomic units was greater in tissue from sheep with ID than H or VFR-affected sheep. Actinobacteria, Bacteriodetes, Firmicutes and Proteobacteria were the most abundant phyla comprising 25 genera. Peptostreptococcus, Corynebacterium and Staphylococcus were associated with H, ID and VFR, respectively. Sequences of Dichelobacter nodosus, the causal agent of ovine footrot, were not amplified because of mismatches in the 16S rRNA universal forward primer (27F). A specific real-time PCR assay was used to demonstrate the presence of D. nodosus, which was detected in all samples including the flock with no signs of ID or VFR. Sheep with ID had significantly higher numbers of D. nodosus (10⁴–10⁹ cells per g tissue) than those with H or VFR feet.     

Embolization itself stimulates thrombus propagation in pulmonary embolism

The role of active thrombosis in the pathophysiology of pulmonary embolism is unclear. We tested the hypothesis that venous thrombi significantly increase their thrombotic activity once they embolize into the high-flow circulation of the pulmonary arteries. Thrombotic activity was measured using an immunoassay that measures both fibrinopeptide B (FPB) as well as its most abundant metabolite des-arginine FPB. Thrombi were formed in the femoral veins of adult dogs. In one group, the thrombi were embolized without anticoagulation. In the second group, heparin (300 U/kg bolus, then 90 U x kg(-1) x h(-1) infusion) was administered before embolization to prevent subsequent thrombotic activity. Plasma FPB concentrations were significantly suppressed in the heparinized group relative to the nonheparinized group for 1 h postembolization (P = 0.038). We conclude that pulmonary embolization itself causes preexisting venous thrombi to greatly intensify their thrombotic activity and that embolization-associated thrombus propagation can be prevented by heparin.