Dystroglycan Depletion Impairs Actin-Dependent Functions of Differentiated Kasumi-1 Cells

Background Dystroglycan has recently been characterised in blood tissue cells, as part of the dystrophin glycoprotein complex involved in the differentiation process of neutrophils. Purpose In the present study we have investigated the role of dystroglycan in the human promyelocytic leukemic cell line Kasumi-1 differentiated to macrophage-like cells. Methods We characterised the pattern expression and subcellular distribution of dystroglycans in non-differentiated and differentiated Kasumi-1 cells. Results Our results demonstrated by WB and flow cytometer assays that during the differentiation process to macrophages, dystroglycans were down-regulated; these results were confirmed with qRT-PCR assays. Additionally, depletion of dystroglycan by RNAi resulted in altered morphology and reduced properties of differentiated Kasumi-1 cells, including morphology, migration and phagocytic activities although secretion of IL-1β and expression of markers of differentiation are not altered. Conclusion Our findings strongly implicate dystroglycan as a key membrane adhesion protein involved in actin-based structures during the differentiation process in Kasumi-1 cells

A role for dystroglycan in the pathophysiology of acute leukemic cells.

AIMS: Previous reports have demonstrated that alterations or reduced expression of Dystroglycan (Dg) complex (αDg and βDg subunits) are related to progression and severity of neoplastic solid tissues. Therefore we determined the expression pattern and subcellular distribution of Dg complex in Acute Myeloid Leukemia (AML) primary blasts (M1, M2, and M3 phenotypes), as well as HL-60 and Kasumi-1 leukemia cell lines. Additionally, we evaluated the relative expression of the main enzymes controlling α-Dg glycosylation to ascertain the post-translational modifications in the leukemia cell phenotype. MAIN METHODS: Primary leukemia blasts and leukemia cell lines were processed by confocal analysis to determine the subcellular distribution of α-Dg, β-Dg, and phosphorylated β-Dg (Y892), to evaluate the expression pattern of the different Dg species we performed Western Blot (WB) assays, while the messenger RNA (mRNA) expression of enzymes involved in α-Dg glycosylation, such as POMGnT1, POMT1, POMT2, LARGE, FKTN, and FKRP, were evaluated by qualitative Reverse Transcription-Polymerase Chain Reaction (qRT-PCR). Finally, in an attempt to ameliorate the leukemia cell phenotype, we transfected leukemia cells with a plasmid expressing the Dg complex. KEY FINDINGS: The Dg complex was altered in leukemia cells, including decreased mRNA, protein, and α-Dg glycosylated levels, mislocalization of β-Dg, and a diminution of mRNA expression of LARGE in patients leukemia blasts and in cell lines. Interestingly, the exogenous expression of Dg complex promoted filopodial formation, differentiation, and diminished proliferation, attenuating some HL-60 and Kasumi cells characteristics. SIGNIFICANCE: Dg complex integrity and balance are required for a proper hematopoietic cell function, in that its disruption might contribute to leukemia pathophysiology

Temporal variations of vegetative features, sex ratios and reproductive phenology in a Dictyota dichotoma (Dictyotales, Phaeophyceae) population of Argentina

This paper addresses the phenology of a Dictyota dichotoma population from the North Patagonian coasts of Argentina. The morphology of the individuals was characterized, and analyses of the temporal variations of vegetative features, diploid and haploid life cycle generations and sex ratios are provided. Individuals, represented by growing sporophytes and gametophytes, occurred simultaneously throughout the year. Morphological variables showed temporal variation, except the width and height of medullary cells, which did not vary between seasons. All vegetative variables were significantly correlated with daylength. Besides, frond length, frond dry mass and apical and basal branching angles were significantly correlated with seawater temperatures. Vegetative thalli were less abundant than haploid and diploid thalli. Sporophytes were less abundant than male and female gametophytes. Male gametophytes dominated in May, August, October and January, and female gametophytes were more abundant in September, November, December, February and March. The formation of female gametangia showed a significant correlation with daylength, and the highest number of gametangia was registered in spring. In general, the male/female sex ratio varied between 1:2 and 1:1. Apical regions were more fertile than basal regions. Our data about frequency in the formation of reproductive structures and male/female ratios are the first recorded in the Dictyota genus and thus could not be compared with populations from other regions of the world. Significant morphological variation was observed in thalli of both life cycle generations, regarding length and dry mass, number of primary branches and branching basal angle. In general, all variables analyzed varied seasonally except cortical cell width.Fil: Gauna, Maria Cecilia. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia. Laboratorio de Ecología Acuática; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Instituto Argentino de Oceanografía (i); ArgentinaFil: Caceres, Eduardo Jorge. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia. Laboratorio de Ficología y Micología; ArgentinaFil: Parodi, Elisa Rosalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Instituto Argentino de Oceanografía (i); Argentina. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia. Laboratorio de Ecología Acuática; Argentin

Materiales compuestos de cerámica y whiskers de alfa-alumina y procedimiento de obtención

[EN] The invention relates to a composite material comprising at least a ceramic matrix and a reinforcing material containing a-alumina whiskers. The invention also relates to a method for obtaining said material and to the use thereof in structural components.[ES] La presente invención se refiere aun material compuestoque comprende al menos una matriz de naturaleza cerámica y un material de refuerzo que comprende whiskers de a-alúmina, a un procedimiento para su obtención, así como al uso del mismo en componentes estructuralesPeer reviewedConsejo Superior de Investigaciones Científicas, Universidad de Santiago de CompostelaA1 Solicitud de patente con informe sobre el estado de la técnic

Leaching of Silver and Gold Contained in a Sedimentary Ore, Using Sodium Thiosulfate; A Preliminary Kinetic Study

Some sedimentary minerals have attractive contents of gold and silver, like a sedimentary exhalative ore available in the eastern of Hidalgo in Mexico. The gold and silver contained represent an interesting opportunity for processing by non-toxic and aggressive leaching reagents like thiosulfate. The preliminary kinetic study indicated that the leaching process was poorly affected by temperature and thiosulfate concentration. The reaction order was −0.61 for Ag, considering a thiosulfate concentration between 200–500 mol·m−3, while, for Au, it was −0.09 for a concentration range between 32–320 mol·m–3. By varying the pH 7–10, it was found that the reaction order was n = 5.03 for Ag, while, for Au, the value was n = 0.94, considering pH 9.5–11. The activation energy obtained during the silver leaching process was 3.15 kJ·mol−1 (298–328 K), which was indicative of a diffusive control of the process. On the other hand, during gold leaching, the activation energy obtained was of 36.44 kJ·mol−1, which was indicative that this process was mixed controlled process, first at low temperatures by diffusive control (298–313 K) and then by chemical control (318–323 K)

Assessment of Silica Recovery from Metallurgical Mining Waste, by Means of Column Flotation

The generation of mining waste commonly led to the use of spaces for its disposal. Challenges like mitigating the damage to surrounding communities have promoted the need to reuse, recycle and/or reduce their generation. Besides, these residues may become a source of materials, which are capable of being recovered and reused in several industries, minimizing the environmental impact. In the mining region of Pachuca, Mexico, waste from the mining industry have been generated for more than 100 years, which have a high SiO2 content that can be recovered for various industrial applications. This work aims to recover silica from a material of the Dos Carlos dam. A columnar system composed of two-stage of cleaning was used, considering a JLT (surface liquid rate) value of 0.45 and 0.68 cm/s, respectively; while the Jg (surface gas rate) value was 0.30 cm/s for both stages. Similar bubble sizes in the range of Jg 0.10 to 0.30 cm/s, with values between 0.14 and 0.16 cm in the first stage, and 0.05 to 0.06 cm in the second one. This provided a recovery of 75.10% for all the allotropic phases of silica (quartz, trydimite, and cristobalite) leaving a concentration of 24.90% of a feldspathic phase (orthoclase), as flotation tails