New polymorphic microsatellite markers for California sea lions (Zalophus californianus)

Nine microsatellite loci were isolated and characterized from California sea lions (Zalophus californianus). In addition, two of five loci tested from harbour seal (Phoca vitulina) produced a single, clear band in Z. californianus, as did one out of five loci from grey seal (Halichoerus grypus) and one out of two loci from elephant seal (Mirounga sp.). No locus tested from South American fur seal (Arctocephalus australis) amplified in Z. californianus. Locus variability was assessed in California sea lions from Los Islotes rookery, Baja California Sur, Mexico. All loci were variable, with allele numbers ranging from three to 12. © 2005 Blackwell Publishing Ltd.Peer Reviewe

Sequence-specific recognition of methylated DNA by human zinc-finger proteins

DNA methylation is an essential epigenetic mark. Three classes of mammalian proteins recognize methylated DNA: MBD proteins, SRA proteins and the zinc-finger proteins Kaiso, ZBTB4 and ZBTB38. The last three proteins can bind either methylated DNA or unmethylated consensus sequences; how this is achieved is largely unclear. Here, we report that the human zinc-finger proteins Kaiso, ZBTB4 and ZBTB38 can bind methylated DNA in a sequence-specific manner, and that they may use a mode of binding common to other zinc-finger proteins. This suggests that many other sequence-specific methyl binding proteins may exist

Intervención comunitaria como pesquisa preventiva para la malnutrición en niños en edad escolar

Objetivo: Determinar la valoración nutricional de los niños de una escuela rural de la zona Mazahua del norte del Estado de México. Material y métodos: Estudio descriptivo transversal basado en una valoración antropométrica y actividades didácticas sobre hábitos alimentarios a 185 escolares (población del estudio) de entre siete y 11 años de una escuela rural de la zona Mazahua del norte del Estado de México, de septiembre a noviembre de 2022; el estudio se realizó en el total de la población. Resultados: La valoración del índice de masa corporal predominante fue normal, destacándose este dato en los niños de sexto grado; seguido de la malnutrición por defecto, destacándose este fenómeno en los niños de segundo grado. En cuanto al completamiento de roles familiares, se obtuvo el predominio de hogares con madres o padres solteros para 76 niños (42,22 %). En cuanto al nivel escolar se obtuvo que solo 26 tutores (14,4 %) poseían nivel de preparatoria y 9 de los tutores (5 %), nivel universitario. Sobre el nivel de preferencia de los niños, en cuanto a los alimentos, prevalecieron los granos integrales (el pan y pizzas) en 162 niños (90 %). Conclusión: La actividad interventora permitió demostrar que la malnutrición continúa siendo un problema de salud de nuestras comunidades infantiles, determinada por la selección inadecuada de los alimentos, el inadecuado complimiento de roles en los hogares y el bajo nivel educacional de padres y tutores

Genome Damage in Rats after Transplacental Exposure to Jatropha dioica Root Extract

Jatropha dioica is traditionally used owing to its antiviral, antifungal, and antimicrobial properties. But, toxicological information regarding J. dioica root total extract is currently limited. The aim of this work was to evaluate in a rat model, the transplacental genotoxicity effect of J. dioica aqueous root total extract. Three different J. dioica aqueous root total extract doses (60, 100, and 300 mg/kg) were administered orally to Wistar rats during 5 days through the pregnancy term (16–21 days). Pregnant rats were sampled every 24 h during the last 6 days of gestation, and pubs were sampled at birth. Genome damage in dams and their newborn pups transplacentally exposed to J. dioica was evaluated by in vivo micronuclei assay. We evaluated the frequency of micronucleated erythrocytes (MNE), micronucleated polychromatic erythrocytes (MNPCE), and polychromatic erythrocytes (PCE) in peripheral blood samples from pups and MNPCE and PCE in pregnant rats. No genotoxic effect was observed after oral administration of the three different doses of aqueous root total extract of J. dioica in pregnant or in their newborn pubs, after transplacental exposure. A significant decrease in PCE frequency was noted in samples from pubs of rats treated with the highest dose of J. dioica extract. The aqueous total root extract of J. dioica at the highest dose tested in our research do have cytotoxic effect in pups transplacentally exposed to this plant extract. Moreover, neither a genotoxic nor a cytotoxic effect was observed in pregnant rats. In the present work, there was no evidence of genome damage in the rat model after transplacental exposure to J. dioica aqueous root total extract

Early Science with the Large Millimeter Telescope: Constraining the Gas Fraction of a Compact Quiescent Galaxy at z=1.883

We present constraints on the dust continuum flux and inferred gas content of a gravitationally lensed massive quiescent galaxy at $z$=1.883$\pm$0.001 using AzTEC 1.1mm imaging with the Large Millimeter Telescope. MRG-S0851 appears to be a prototypical massive compact quiescent galaxy, but has evidence that it experienced a centrally concentrated rejuvenation event in the last 100 Myr (see Akhshik et al. 2020). This galaxy is undetected in the AzTEC image but we calculate an upper limit on the millimeter flux and use this to estimate the H$_2$ mass limit via an empirically calibrated relation that assumes a constant molecular gas-to-dust ratio of 150. We constrain the 3$\sigma$ upper limit of the H$_2$ fraction from the dust continuum in MRG-S0851 to be ${M_{H_2}/M_{\star}}$ $\leq$ 6.8%. MRG-S0851 has a low gas fraction limit with a moderately low sSFR owing to the recent rejuvenation episode, which together results in a relatively short depletion time of $<$0.6 Gyr if no further H$_2$ gas is accreted. Empirical and analytical models both predict that we should have detected molecular gas in MRG-S0851, especially given the rejuvenation episode; this suggests that cold gas and/or dust is rapidly depleted in at least some early quiescent galaxies.Comment: 8 pages, 4 figures, accepted for publication in Astrophysical Journal Letters in January 2021 (in press

Renal and Blood Pressure Response to a High-Salt Diet in Mice With Reduced Global Expression of the Glucocorticoid Receptor

Salt-sensitive hypertension is common in glucocorticoid excess. Glucocorticoid resistance also presents with hypercortisolemia and hypertension but the relationship between salt intake and blood pressure (BP) is not well defined. GRβgeo/+ mice have global glucocorticoid receptor (GR) haploinsufficiency and increased BP. Here we examined the effect of high salt diet on BP, salt excretion and renal blood flow in GRβgeo/+mice. Basal BP was ∼10 mmHg higher in male GRβgeo/+ mice than in GR+/+ littermates. This modest increase was amplified by ∼10 mmHg following a high-salt diet in GRβgeo/+ mice. High salt reduced urinary aldosterone excretion but increased renal mineralocorticoid receptor expression in both genotypes. Corticosterone, and to a lesser extent deoxycorticosterone, excretion was increased in GRβgeo/+ mice following a high-salt challenge, consistent with enhanced 24 h production. GR+/+ mice increased fractional sodium excretion and reduced renal vascular resistance during the high salt challenge, retaining neutral sodium balance. In contrast, sodium excretion and renal vascular resistance did not adapt to high salt in GRβgeo/+ mice, resulting in transient sodium retention and sustained hypertension. With high-salt diet, Slc12a3 and Scnn1a mRNAs were higher in GRβgeo/+ than controls, and this was reflected in an exaggerated natriuretic response to thiazide and benzamil, inhibitors of NCC and ENaC, respectively. Reduction in GR expression causes salt-sensitivity and an adaptive failure of the renal vasculature and tubule, most likely reflecting sustained mineralocorticoid receptor activation. This provides a mechanistic basis to understand the hypertension associated with loss-of-function polymorphisms in GR in the context of habitually high salt intake

ADP-ribose polymers localized on Ctcf–Parp1–Dnmt1 complex prevent methylation of Ctcf target sites

PARylation [poly(ADP-ribosyl)ation] is involved in the maintenance of genomic methylation patterns through its control of Dnmt1 [DNA (cytosine-5)-methyltransferase 1] activity. Our previous findings indicated that Ctcf (CCCTC-binding factor) may be an important player in key events whereby PARylation controls the unmethylated status of some CpG-rich regions. Ctcf is able to activate Parp1 [poly(ADP-ribose) polymerase 1], which ADP-ribosylates itself and, in turn, inhibits DNA methylation via non-covalent interaction between its ADP-ribose polymers and Dnmt1. By such a mechanism, Ctcf may preserve the epigenetic pattern at promoters of important housekeeping genes. The results of the present study showed Dnmt1 as a new protein partner of Ctcf. Moreover, we show that Ctcf forms a complex with Dnmt1 and PARylated Parp1 at specific Ctcf target sequences and that PARylation is responsible for the maintenance of the unmethylated status of some Ctcf-bound CpGs. We suggest a mechanism by which Parp1, tethered and activated at specific DNA target sites by Ctcf, preserves their methylation-free status

The 2HWC HAWC Observatory Gamma Ray Catalog

We present the first catalog of TeV gamma-ray sources realized with the recently completed High Altitude Water Cherenkov Observatory (HAWC). It is the most sensitive wide field-of-view TeV telescope currently in operation, with a 1-year survey sensitivity of ~5-10% of the flux of the Crab Nebula. With an instantaneous field of view >1.5 sr and >90% duty cycle, it continuously surveys and monitors the sky for gamma ray energies between hundreds GeV and tens of TeV. HAWC is located in Mexico at a latitude of 19 degree North and was completed in March 2015. Here, we present the 2HWC catalog, which is the result of the first source search realized with the complete HAWC detector. Realized with 507 days of data and represents the most sensitive TeV survey to date for such a large fraction of the sky. A total of 39 sources were detected, with an expected contamination of 0.5 due to background fluctuation. Out of these sources, 16 are more than one degree away from any previously reported TeV source. The source list, including the position measurement, spectrum measurement, and uncertainties, is reported. Seven of the detected sources may be associated with pulsar wind nebulae, two with supernova remnants, two with blazars, and the remaining 23 have no firm identification yet.Comment: Submitted 2017/02/09 to the Astrophysical Journa

The Sensitivity of HAWC to High-Mass Dark Matter Annihilations

The High Altitude Water Cherenkov (HAWC) observatory is a wide field-of-view detector sensitive to gamma rays of 100 GeV to a few hundred TeV. Located in central Mexico at 19 degrees North latitude and 4100 m above sea level, HAWC will observe gamma rays and cosmic rays with an array of water Cherenkov detectors. The full HAWC array is scheduled to be operational in Spring 2015. In this paper, we study the HAWC sensitivity to the gamma-ray signatures of high-mass (multi- TeV) dark matter annihilation. The HAWC observatory will be sensitive to diverse searches for dark matter annihilation, including annihilation from extended dark matter sources, the diffuse gamma-ray emission from dark matter annihilation, and gamma-ray emission from non-luminous dark matter subhalos. Here we consider the HAWC sensitivity to a subset of these sources, including dwarf galaxies, the M31 galaxy, the Virgo cluster, and the Galactic center. We simulate the HAWC response to gamma rays from these sources in several well-motivated dark matter annihilation channels. If no gamma-ray excess is observed, we show the limits HAWC can place on the dark matter cross-section from these sources. In particular, in the case of dark matter annihilation into gauge bosons, HAWC will be able to detect a narrow range of dark matter masses to cross-sections below thermal. HAWC should also be sensitive to non-thermal cross-sections for masses up to nearly 1000 TeV. The constraints placed by HAWC on the dark matter cross-section from known sources should be competitive with current limits in the mass range where HAWC has similar sensitivity. HAWC can additionally explore higher dark matter masses than are currently constrained.Comment: 15 pages, 4 figures, version to be published in PR

Novel CTCF binding at a site in exon1A of BCL6 is associated with active histone marks and a transcriptionally active locus

BCL6 is a zinc-finger transcriptional repressor, which is highly expressed in germinal centre B-cells and is essential for germinal centre formation and T-dependent antibody responses. Constitutive BCL6 expression is sufficient to produce lymphomas in mice. Deregulated expression of BCL6 due to chromosomal rearrangements, mutations of a negative autoregulatory site in the BCL6 promoter region and aberrant post-translational modifications have been detected in a number of human lymphomas. Tight lineage and temporal regulation of BCL6 is, therefore, required for normal immunity, and abnormal regulation occurs in lymphomas. CCCTC-binding factor (CTCF) is a multi-functional chromatin regulator, which has recently been shown to bind in a methylation-sensitive manner to sites within the BCL6 first intron. We demonstrate a novel CTCF-binding site in BCL6 exon1A within a potential CpG island, which is unmethylated both in cell lines and in primary lymphoma samples. CTCF binding, which was found in BCL6-expressing cell lines, correlated with the presence of histone variant H2A.Z and active histone marks, suggesting that CTCF induces chromatin modification at a transcriptionally active BCL6 locus. CTCF binding to exon1A was required to maintain BCL6 expression in germinal centre cells by avoiding BCL6-negative autoregulation. Silencing of CTCF in BCL6-expressing cells reduced BCL6 mRNA and protein expression, which is sufficient to induce B-cell terminal differentiation toward plasma cells. Moreover, lack of CTCF binding to exon1A shifts the BCL6 local chromatin from an active to a repressive state. This work demonstrates that, in contexts in which BCL6 is expressed, CTCF binding to BCL6 exon1A associates with epigenetic modifications indicative of transcriptionally open chromatin