Negative serology of Fasciola hepatica infection in patients with liver cancer in Peru: A preliminary report

Introduction: The etiology of several hepatocellular carcinoma (HCC) cases remains largely unknown. Although Fasciola hepatica has been associated with liver fibrosis in Latin America, it has not yet been associated with HCC. This study aimed to determine the existence of specific IgG antibodies against F. hepatica in the serum samples of HCC patients. Methods: In total, 13 serum samples from 13 HCC patients were screened using Fas2-ELISA. Results: Fas2-ELISA demonstrated negative results in all HCC patients included in this study. Conclusions: The pre-existence of F. hepatica infection in HCC patients needs to be further investigated in epidemiological and experimental studies

Star-forming galaxies versus low- and high-excitation radio AGN in the VLA-COSMOS 3GHz Large Project

We study the composition of the faint radio population selected from the VLA-COSMOS 3GHz Large Project, a radio continuum survey performed at 10 cm wavelength. The survey covers the full 2 square degree COSMOS field with mean $rms\sim2.3$ $\mu$Jy/beam, cataloging 10,899 source components above $5\times rms$. By combining these radio data with UltraVISTA, optical, near-infrared, and Spitzer/IRAC mid-infrared data, as well as X-ray data from the Chandra Legacy, and Chandra COSMOS surveys, we gain insight into the emission mechanisms within our radio sources out to redshifts of $z\sim5$. From these emission characteristics we classify our souces as star forming galaxies or AGN. Using their multi-wavelength properties we further separate the AGN into sub-samples dominated by radiatively efficient and inefficient AGN, often referred to as high- and low-excitation emission line AGN. We compare our method with other results based on fitting of the sources' spectral energy distributions using both galaxy and AGN spectral models, and those based on the infrared-radio correlation. We study the fractional contributions of these sub-populations down to radio flux levels of $\sim$10 $\mu$Jy. We find that at 3 GHz flux densities above $\sim$400 $\mu$Jy quiescent, red galaxies, consistent with the low-excitation radio AGN class constitute the dominant fraction. Below densities of $\sim$200 $\mu$Jy star-forming galaxies begin to constitute the largest fraction, followed by the low-excitation, and X-ray- and IR-identified high-excitation radio AGN.Comment: 7 pages, 3 figures, The many facets of extragalactic radio surveys: towards new scientific challenges, Bologna 20-23 October 201

Short communication: Performance, intestinal permeability, and metabolic profile of calves fed a milk replacer supplemented with glutamic acid

The objective of this study was to evaluate the potential benefits of supplementing glutamic acid in milk replacers (MR) with respect to calf performance, intestinal permeability, and metabolism. Sixty Holstein male calves (3 ± 1.3 d old and 45 ± 5.9 kg body weight) were individually housed and fed a control MR without AA supplementation (24.8% crude protein and 19.1% fat, dry matter basis), or MR supplemented with 0.3% glutamic acid (25.1% crude protein and 20.3% fat, dry matter basis). Animals followed the same MR feeding program and were weaned at 56 d of the study. The amount of starter concentrate offered was restricted to limit the effect of concentrate intake on calf metabolism. Individual daily consumption and weekly body weight were measured, and 4 h after the morning feeding, blood samples were obtained at 14 and 35 d to determine general biochemical parameters and plasma AA concentrations. On d 10 of the study, we conducted an intestinal permeability test by including 21 g of lactulose and 4.2 g of d-mannitol as markers in the MR. We found no differences in calf performance or in intestinal permeability (measured as lactulose:mannitol ratio). Serum glucose concentration was greater in unsupplemented calves than in Glu-supplemented calves. At 14 d, the proportion of plasma Leu was greater in Glu-supplemented calves; the proportion of Ile tended to be greater in Glu-supplemented calves; and the proportion of Met tended to be greater in unsupplemented calves. We observed no other differences. Small changes occurred in AA metabolism when supplementing calf MR with 0.3% glutamic acid, without leading to improvements in calf performance or changes in intestinal permeability.info:eu-repo/semantics/publishedVersio

Limited Lifespan of Fragile Regions in Mammalian Evolution

An important question in genome evolution is whether there exist fragile regions (rearrangement hotspots) where chromosomal rearrangements are happening over and over again. Although nearly all recent studies supported the existence of fragile regions in mammalian genomes, the most comprehensive phylogenomic study of mammals (Ma et al. (2006) Genome Research 16, 1557-1565) raised some doubts about their existence. We demonstrate that fragile regions are subject to a "birth and death" process, implying that fragility has limited evolutionary lifespan. This finding implies that fragile regions migrate to different locations in different mammals, explaining why there exist only a few chromosomal breakpoints shared between different lineages. The birth and death of fragile regions phenomenon reinforces the hypothesis that rearrangements are promoted by matching segmental duplications and suggests putative locations of the currently active fragile regions in the human genome

Beta-glucan reflects liver injury after preservation and transplantation in dogs.

Graft failure and extrahepatic organ complications, which frequently develop after transplantation, may be related to inflammatory mediators stimulated by endotoxin (ET). The role of endotoxemia after liver transplantation is controversial and may depend upon differences in the ET assay method used in the various contradicting studies. While the standard Limulus amebocyte lysate (LAL) is reactive for ET and beta-glucan, a novel turbidimetric assay method enables separate determinations of ET and beta-glucan. Beagle dogs undergoing orthotopic liver transplantation were divided into two groups. In Group I (n = 6) the grafts were transplanted immediately and in Group II (n = 6) grafts were preserved for 48 h in University of Wisconsin (UW) solution. Animals received cyclosporine immunosuppression and were followed for 14 days. Daily measurements of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH) were performed. Samples for ET and beta-glucan measurement were collected serially and processed using the turbidimetric assay method. While no graft failure was seen in Group I, three of six Group II animals died from graft failure within 1 day after transplantation. Preservation and reperfusion injury was much more severe in the Group II grafts than in Group I grafts. While endotoxemia could not be detected, postoperative beta-glucan levels (undetectable pretransplant) were seen in both groups. Beta-glucan levels were much higher in Group II grafts than in Group I grafts, and correlated with the severity of liver damage. In conclusion, this study shows that beta-glucan, instead of ET, appears during the early posttransplant period. We believe that posttransplant elevation of beta-glucan is related to liver damage, especially endothelial damage by preservation and reperfusion

Gaseous time projection chambers for rare event detection: Results from the T-REX project. II. Dark matter

As part of the T-REX project, a number of R&D and prototyping activities have been carried out during the last years to explore the applicability of Micromegas-read gaseous TPCs in rare event searches like double beta decay (DBD), axion research and low-mass WIMP searches. While in the companion paper we focus on DBD, in this paper we focus on the results regarding the search for dark matter candidates, both axions and WIMPs. Small ultra-low background Micromegas detectors are used to image the x-ray signal expected in axion helioscopes like CAST at CERN. Background levels as low as $0.8\times 10^{-6}$ c keV$^{-1}$cm$^{-2}$s$^{-1}$ have already been achieved in CAST while values down to $\sim10^{-7}$ c keV$^{-1}$cm$^{-2}$s$^{-1}$ have been obtained in a test bench placed underground in the Laboratorio Subterr\'aneo de Canfranc. Prospects to consolidate and further reduce these values down to $\sim10^{-8}$ c keV$^{-1}$cm$^{-2}$s$^{-1}$will be described. Such detectors, placed at the focal point of x-ray telescopes in the future IAXO experiment, would allow for 10$^5$ better signal-to-noise ratio than CAST, and search for solar axions with $g_{a\gamma}$ down to few 10$^{12}$ GeV$^{-1}$, well into unexplored axion parameter space. In addition, a scaled-up version of these TPCs, properly shielded and placed underground, can be competitive in the search for low-mass WIMPs. The TREX-DM prototype, with $\sim$0.300 kg of Ar at 10 bar, or alternatively $\sim$0.160 kg of Ne at 10 bar, and energy threshold well below 1 keV, has been built to test this concept. We will describe the main technical solutions developed, as well as the results from the commissioning phase on surface. The anticipated sensitivity of this technique might reach $\sim10^{-44}$ cm$^2$ for low mass ($<10$ GeV) WIMPs, well beyond current experimental limits in this mass range.Comment: Published in JCAP. New version with erratum incorporated (new figure 14

Phenotypic comparison of samdc and spe mutants reveals complex relationships of polyamine metabolism in Ustilago maydis

Synthesis of spermidine involves the action of two enzymes, spermidine synthase (Spe) and Sadenosylmethionine decarboxylase (Samdc). Previously we cloned and disrupted the gene encoding Spe as a first approach to unravel the biological function of spermidine in Ustilago maydis. With this background, the present study was designed to provide a better understanding of the role played by Samdc in the regulation of the synthesis of this polyamine. With this aim we proceeded to isolate and delete the gene encoding Samdc from U. maydis, and made a comparative analysis of the phenotypes of samdc and spe mutants. Both spe and samdc mutants behaved as spermidine auxotrophs, and were more sensitive than the wild-type strain to different stress conditions. However, the two mutants displayed significant differences: in contrast to spe mutants, samdc mutants were more sensitive to LiCl stress, high spermidine concentrations counteracted their dimorphic deficiency, and they were completely avirulent. It is suggested that these differences are possibly related to differences in exogenous spermidine uptake or the differential location of the respective enzymes in the cell. Alternatively, since samdc mutants accumulate higher levels of S-adenosylmethionine (SAM), whereas spe mutants accumulate decarboxylated SAM, the known opposite roles of these metabolites in the processes of methylation and differentiation offer an additional attractive hypothesis to explain the phenotypic differences of the two mutants, and provide insights into the additional roles of polyamine metabolism in the physiology of the cell. INTRODUCTION Polyamines are organic polycations required by all living organisms Cell and Molecular Biology of Microbes Abbreviations: dcSAM, decarboxylated S-adenosylmethionine; ODC, ornithine decarboxylase; SAM, S-adenosylmethionine. The GenBank/EMBL/DDBJ accession number for the SAMDC gene sequence of U. maydis is HE582743. Microbiology (2012), 158, 000-000 DOI 10.1099/mic.0.055954-0 055954 G 2012 SGM Printed in Great Britain 1 polyamine required for U. maydis dimorphism. Synthesis of this polyamine requires the action of two enzymes, spermidine synthase (Spe) and S-adenosylmethionine decarboxylase (Samdc). The latter enzyme is responsible for the decarboxylation of S-adenosylmethionine (SAM) with formation of decarboxylated SAM (dcSAM), which serves as donor of a propylamine group to putrescine in a reaction catalysed by Spe It is known that Samdc is synthesized as a proenzyme that subsequently undergoes an intramolecular cleavage at a serine residue to generate two non-identical subunits termed a and b, both of which are indispensable components of the mature enzyme Besides this multiplicity, gene disruption studies have demonstrated that spermidine is essential for vegetative growth and differentiation, while putrescine is only the precursor of higher polyamines and appears to have a minor role in the stress response and/or virulence U. maydis, a plant-pathogenic Basidiomycota fungus, is an excellent model for the study of different biological phenomena, such as fungal phytopathogenicity, DNA recombination and repair, long-distance transport in hyphal growth, mitosis, and dimorphism Previously we reported the isolation and phenotype of U. maydis spe mutants (Valdés-Santiago et al., 2009), and in this communication we describe the isolation and mutation of the SAMDC gene, which permitted the determination of the similarities and differences that exist between the phenotypic behaviour of samdc and that of the previously obtained spe mutants. METHODS Strains and growth conditions. U. maydis haploid strains Nucleic acid manipulation. Isolation of genomic DNA was conducted as reported by Plasmid constructs. To delete the gene encoding U. maydis Samdc (SAMDC), plasmid pDsamdc was constructed. Briefly, the full gene including its 59 and 39 flanking sequences was amplified by PCR with primers Samdc5 and Samdc3 (Table 2) using genomic DNA from U. maydis strain FB2 To complement U. maydis samdc mutants, a plasmid was constructed as follows. The full SAMDC gene including its promoter and terminator was PCR-amplified using primers Samdc5 and Samdc3. The PCR product (3.1 kb) was cloned into plasmid pCR2.1 (Invitrogen), generating plasmid pSAMDC. Next, the SAMDC gene was recovered as a BamHI-NotI fragment and cloned into the same sites of the episomal plasmid pHyg101 Mating analysis. Mating was analysed by the &apos;fuz&apos; reaction Stress assays. To determine the sensitivity of U. maydis to different compounds, decimal dilutions of cell suspensions were inoculated on plates of solid media amended with the compound to be tested, and growth was assessed as described previously (Valdés-Santiago et al., 2009). Virulence assays. These were performed as previously described (Martínez-Espinoza et al., 1997). Briefly, 10 day-old seedlings of maize cv cacahuazintle were inoculated using a syringe and needle with a mixture of sexually compatible strains. The plants were kept in a greenhouse, and symptoms were recorded for 15 days after inoculation. Isolation of segregants from inoculated plants. Teliospores produced in the tumours induced in maize plants inoculated with sexually compatible U. maydis strains were suspended in 1.5 % CuSO 4 for 2 h to kill vegetative cells, filtered through cheesecloth, washed twice with sterile distilled water, recovered by centrifugation and plated on solid CM. After 12-18 h, the sporidia formed by germination of teliospores were recovered by washing the plates with sterile distilled water, and inoculated on plates containing hygromycin B and/or carboxin to determine their phenotype (ChavezOntiveros et al., 2000). Mating type (fuz reaction, see above) and auxotrophy to spermidine were tested in segregants thus obtained. Determination of SAM and dcSAM levels. U. maydis cells were grown in liquid MM with addition of 0.1 mM spermidine or other requirements (see Methods and the legend to Disruption of the SAMDC gene using an odc mutant as a recipient strain Essentially we followed the method of Auxotrophic requirements of the odc/samdc double mutants Taking into consideration that the SAMDC gene encodes an enzyme essential for spermidine synthesis, we expected that odc/samdc double mutants would require the enzyme to grow. Mutants were able to grow on two subcultures without polyamines, after which their polyamine pools were exhausted and they failed to grow in media without polyamines, although they grew in the presence of 0.1 or 0.5 mM spermidine at a rate comparable with that of the wild-type (results not shown). Although odc/samdc mutants were unable to produce putrescine through the ODC pathway, the spermidine acetylase-oxidase route (Valdés-Santiago et al., 2009 provided enough of this polyamine to cover their requirements Isolation of samdc single mutants by sexual recombination in planta Using sexual recombination in planta between an a2b2 odc/ samdc double mutant and the FB1 wild-type strain (a1b1), it was possible to isolate a set of single samdc mutants, selecting strains 5-11 (samdc : : Cbx R a1b1) and LV71 (samdc : : Cbx R a2b2) to conduct further studies. Mutants were confirmed by Northern analysis (results not shown). Complementation of samdc mutants Through transformation of a samdc mutant with a plasmid containing a functional copy of the SAMDC gene, it was possible to obtain SAMDC revertant strains (4samdcR, 11samdcR, 7samdcR) resistant to carboxin and hygromicin. The presence of the SAMDC gene in these strains restored the capacity to grow in the absence of spermidine. Effect of different stress conditions on samdc mutants The effect of 10 mM LiCl, 3 mM H 2 O 2 , different concentrations of menadione, 0.005 or 0.05 mM Rose Bengal (RB), 0.2 or 0.7 mM ascorbic acid, 1 M sorbitol, 0.5 M CaCl 2 or 1 M NaCl on cell growth was assayed as described in Methods. Polyamine pools of the U. maydis mutants were depleted by subculturing twice in polyaminefree medium, followed by inoculation on plates supplemented with 0.1 mM spermidine. In the absence of inhibitors only slightly reduced growth rates were observed for 5-11 (samdc) and LV54 (spe) mutants as compared with the FB2 wild-type (control) and 4samdcR (revertant) strains %paper no. mic055954 charlesworth ref: mic055954&amp; L. Valdé s-Santiago and others 4 Microbiology Dimorphic transition induced by acid pH U. maydis grows in the yeast form at neutral pH, and in the hyphal form at acid pH Mating analysis We observed a concentration-dependent effect of spermidine on mating of homologous strains of both types of mutants: 5-11 (a1b1 Dsamdc : : Cbx . In both cases, the intensity of dikaryon formation increased, as revealed by the appearance of white fuzzy filamentous colonies as we raised the concentration of spermidine (see Virulence studies In contrast to spe mutants, which generate tumours in about 20 % of infected maize plants (Valdés-Santiago et al., 2009), samdc mutants proved to be completely avirulent to maize plants: out of a total of 128 plants inoculated with a mixture of 5-11 and LV71 samdc sexually compatible mutants, not a single one developed tumours, whereas 76.9 % of maize plants (out of a total of 79 plants) inoculated with a mixture of FB1and FB2 strains formed tumours. This avirulent phenotype agrees with the behaviour of odc mutants, which are also unable to induce tumours in maize plant