Laboratorio Of Biologia Molecular

Dolores Hidalgo Cuna de la Independencia Nacional, Mexico

Laboratorio Of Biologia Molecular

Dolores Hidalgo Cuna de la Independencia Nacional, Mexico
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Tume Farfan L.F.,National University of Piura | Tume Farfan L.F.,Laboratorio Of Biologia Molecular
Inmunologia | Year: 2014

There is evidence that supports the hypothesis of the existence of cancer stem cells (CSC), in which it postulates that these are responsible for the initiation, recurrence, metástasis, and resistance to cancer treatments, thus creating a need for therapies that specifically target these subpopulations of cells with stem cell characteristics in most malignant tumors with mixed cell phenotypes. Since its advent, immunotherapy has been used as an attractive approach due to the many shortcomings of conventional surgery, radiotherapy and chemotherapy in the treatment of cancer. Within tumor subsets neoplastically transformed cells demonstrate surface expression of molecules that are not typically present on the surface of the surrounding normal cells. In some cases, especially in malignant melanoma, the cytotoxic T lymphocytes (CTL) directed against tumor associated antigens (TAA) have been isolated to raise antibodies and somehow reduce the disease. The focus of cancer vaccine therapy is based on the idea that the immune system could mount a rejection response force against conglomerate neoplastically transformed cells. However, due to the low immunogenicity of TAA, down-regulation of MHC molecules, the lack of expression of appropriate co-stimulatory molecule, cytokine secretion inmunoinhibitorias etc., they rarely met expectations. This is why new markers that are not only safe and allow immunotherapy directed against CSC are now being sought, but also tumor eradication could be achieved with the combination of many therapies in order to have an efficient outcome in the treatment of this disease currently affecting the world. © 2014 Sociedad Espanola de Inmunologia.

Jarillo-Luna A.,National Polytechnic Institute of Mexico | Rivera-Aguilar V.,National Autonomous University of Mexico | Miliar-Garcia A.,Laboratorio Of Biologia Molecular
Immunology Letters | Year: 2010

Few reports exist on the differences in cell populations or immunological functions between the proximal and distal segments of the small intestine (SI). In the current contribution we analyzed the expression of the polymeric immunoglobulin receptor (pIgR) and alpha chains as well as the density of IgA-producing cells from the proximal and distal intestinal segments from Balb/c mice. Furthermore, by using real-time RT-PCR we quantified the expression of cytokines (TNF-α, IFN-γ, IL-4 and TGF-β), Toll-like receptor-4 (TLR-4), and the glucocorticoid receptor (GR) involved in pIgR expression in intestinal epithelial cells (IEC). In this study, for the first time it has been demonstrated that the expression of the pIgR as well as alpha chain was greater in the proximal than the distal segment of the small intestine of normal mice. Moreover, we found striking differences in the expression of cytokines at the different intestinal compartments. Whereas the expression of TNF-α, IFN-γ and TGF-β was higher in lamina propria lymphocytes (LPL) of the distal than proximal segment, it was higher in IEC of the proximal than distal segment. In contrast, the expression of the gene for IL-4 was higher in the LPL of the proximal segment and the IEC of the distal segment. Although the overall expression of TNF-α, IL-4, IFN-γ and TGF-β was higher in the whole mucosa of the distal than proximal segment, we propose that cytokines produced by epithelial cells (TNF-α, IFN-γ and TGF-β) autocrinally up-regulate the expression of mRNA for the pIgR. Finally the expression of the GR was higher in the proximal segment, while the expression of the gene for TLR-4 was significantly higher in the IEC of the distal than proximal segment. The higher expression of pIgR found in the proximal segment is probably related to the effect on epithelial cells of the higher production of TNF-α, IFN-γ and TGF-β, as well as the higher expression of the glucocorticoid receptors. The increased expression of pIgR in the proximal segment appears primarily responsible for the increased secretory IgA levels in the small intestine of mice. These results confirm and extend previous findings supporting the compartmentalization of the intestinal immune system. © 2009 Elsevier B.V. All rights reserved.

Gentile C.,Laboratorio Of Biologia Molecular | Rivas G.B.,Laboratorio Of Biologia Molecular | Lima J.B.,Brazilian National Institute of Technology | Bruno R.V.,Laboratorio Of Biologia Molecular | Peixoto A.A.,Laboratorio Of Biologia Molecular
Memórias do Instituto Oswaldo Cruz | Year: 2013

Mosquitoes are the culprits of some of the most important vector borne diseases. A species' potential as a vector is directly dependent on their pattern of behaviour, which is known to change according to the female's physiological status such as whether the female is virgin/mated and unfed/blood-fed. However, the molecular mechanism triggered by and/or responsible for such modulations in behaviour is poorly understood. Clock genes are known to be responsible for the control of circadian behaviour in several species. Here we investigate the impact mating and blood-feeding have upon the expression of these genes in the mosquito Aedes aegypti. We show that blood intake, but not insemination, is responsible for the down-regulation of clock genes. Using RNA interference, we observe a slight reduction in the evening activity peak in the fourth day after dstim injection. These data suggest that, as in Drosophila, clock gene expression, circadian behaviour and environmental light regimens are interconnected in Ae. aegypti.

Perez-Roth E.,Laboratorio Of Biologia Molecular | Kwong S.M.,University of Sydney | Alcoba-Florez J.,Laboratorio Of Biologia Molecular | Firth N.,University of Sydney | And 3 more authors.
Antimicrobial Agents and Chemotherapy | Year: 2010

We have sequenced the conjugative plasmid pPR9, which carries the ileS2 gene, which had contributed to the dissemination of high-level mupirocin resistance at our institution. The plasmid backbone shows extensive genetic conservation with plasmids belonging to the pSK41/pGO1 family, but comparative analyses have revealed key differences that provide important insights into the evolution of these medically important plasmids and high-level mupirocin resistance in staphylococci and highlight the role of insertion sequence IS257 in these processes. Copyright © 2010, American Society for Microbiology. All Rights Reserved.

Rodriguez-Cruz M.,Laboratorio Of Biologia Molecular | Sanchez R.,Laboratorio Of Biologia Molecular | Sanchez A.M.,Laboratorio Of Biologia Molecular | Kelleher S.L.,Pennsylvania State University | And 3 more authors.
Biochimica et Biophysica Acta - Molecular and Cell Biology of Lipids | Year: 2011

Metabolic adaptations are triggered in the maternal organism to synthesize milk with an adequate concentration of long-chain polyunsaturated fatty acids (LC-PUFAs) required to the newborn. They may be a high uptake of dietary linoleic acid and its conversion to LC-PUFAs by desaturases of fatty acids (FADS) 1 and 2 in the mammary gland (MG). It is unknown if they also occur from onset of pregnancy. The aim of this study was to explore the participation of the MG as a mechanism involved in LC-PUFAs synthesis to support their demand during pregnancy and lactation in rats. The expression of desaturases in MG was significantly (P < 0.05) higher (12.3-fold for FADS1 and 41.2-fold for FADS2) during the late pregnancy and throughout lactation (31.7-fold for FADS1 and 67.1-fold higher for FADS2) than in nonpregnant rats. SREBF-1c showed a similar pattern of increase during pregnancy but remained higher only during the early lactation (11.7-fold, P < 0.005). Transcript of ELOVL6 and FASN increased throughout pregnancy and lactation, respectively. ELOVL5 mRNA increased in MG only during lactation (2.8 to 5.3-fold, P < 0.005). Accordingly, a higher content of LC-PUFAs was found in lactating MG than in nonpregnant rats. Results suggest that MG participates from late pregnancy and throughout lactation by expressing desaturases and elongases as a mechanism involved in LC-PUFAs synthesis, probably by SREBF-1c. Because desaturases and ELOVL5 were expressed in cultured lactocytes and such expression was downregulated by linoleic and arachidonic acid, these cells may be a useful model for understanding the regulatory mechanisms for LC-PUFAs synthesis in MG. © 2011 Elsevier B.V. All rights reserved.

Lax P.,National University of Cordoba | Rondan Duenas J.C.,Laboratorio Of Biologia Molecular | Gardenal C.N.,National University of Cordoba | Doucet M.E.,National University of Cordoba
Zoologica Scripta | Year: 2014

The plant-parasitic nematode Nacobbus aberrans sensu lato is an agricultural pest of quarantine importance. Due to the morphometric, physiological and genetic variability observed within the species, there is no agreement on the taxonomy of this nematode. The objective of this study was to analyse the ITS rDNA region and the D2-D3 expansion segments of 28S rDNA in 10 Argentine populations and one from Ecuador and to establish their phylogenetic relationship with other known sequences from South and North America. Phylogenetic trees of the ITS gene showed seven statistically well-supported clades; the high and significant Fst values obtained among these groups confirmed this partitioning. The Argentine populations here considered were separated into three clades: one comprising a population from the Andean region and two grouping nematodes from lower altitudes. Three other clades were distinguished for South American populations, which included known sequences of individuals from Peru, Bolivia and north of Argentina. The other clade included sequences from Mexico, Ecuador and two Argentine populations of unknown origin. The important degree of genetic divergence observed among Andean populations suggests that the Andes may have played a crucial role in speciation of Nacobbus, which would have originated in this region. Although D2-D3 segments exhibited lower variation, they were useful for establishing phylogenetic relationships among the Argentine populations considered in this work. As there are no other GenBank sequences available for these segments, it was not possible to make comparisons with other populations from South and North America. The considerable genetic differentiation observed in ITS rDNA region among Nacobbus populations showed evidence of cryptic species within the N. aberrans s.l. complex. Integration of morphological and morphometric studies and molecular analyses considering other genes may aid in the identification of species and their phylogenetic relationships within this genus. © 2013 The Norwegian Academy of Science and Letters.

PubMed | Laboratorio Of Biologia Molecular, National University of Santa and National University of Cordoba
Type: Journal Article | Journal: Systematic parasitology | Year: 2017

Entomopathogenic nematodes of the families Heterorhabditidae Poinar, 1976 and Steinernematidae Chitwood & Chitwood, 1937 are used for biological control of insect pests. An isolate of Steinernema diaprepesi Nguyen & Duncan, 2002 was recovered from a carrot field in the locality of Santa Rosa de Calchines (Santa Fe Province, Argentina). These nematodes were characterised based on morphological, morphometric and molecular studies. Their symbiotic bacterium was identified as Xenorhabdus doucetiae Tailliez, Pags, Ginibre & Boemare, 2006 by sequencing the 16S rRNA gene. The isolate of S. diaprepesi studied exhibits some morphometric differences with the original description, especially in the first generation adults. This is the first description of the species in Argentina.

Bonome Zeminian L.,Laboratorio Of Biologia Molecular | Lara Padovani J.,Laboratorio Of Biologia Molecular | Maria Corvino S.,Laboratorio Of Biologia Molecular | Faria Silva G.,São Paulo State University | And 3 more authors.
Memorias do Instituto Oswaldo Cruz | Year: 2013

The goal of treatment of chronic hepatitis C is to achieve a sustained virological response, which is defined as exhibiting undetectable hepatitis C virus (HCV) RNA levels in serum following therapy for at least six months. However, the current treatment is only effective in 50% of patients infected with HCV genotype 1, the most prevalent genotype in Brazil. Inhibitors of the serine protease non-structural protein 3 (NS3) have therefore been developed to improve the responses of HCV-infected patients. However, the emergence of drug-resistant variants has been the major obstacle to therapeutic success. The goal of this study was to evaluate the presence of resistance mutations and genetic polymorphisms in the NS3 genomic region of HCV from 37 patients infected with HCV genotype 1 had not been treated with protease inhibitors. Plasma viral RNA was used to amplify and sequence the HCV NS3 gene. The results indicate that the catalytic triad is conserved. A large number of substitutions were observed in codons 153, 40 and 91; the resistant variants T54A, T54S, V55A, R155K and A156T were also detected. This study shows that resistance mutations and genetic polymorphisms are present in the NS3 region of HCV in patients who have not been treated with protease inhibitors, data that are important in determining the efficiency of this new class of drugs in Brazil.

Martinez E.M.,Laboratorio Of Biologia Molecular
Revista del Instituto Nacional de Enfermedades Respiratorias | Year: 2010

The emergence of a new member of the renin-angiotensin system, the renin /prorenin receptor revealed an unexpected role of this system different to its classical in the regulation of blood pressure. Recent evidences indicate that the renin/prorenin receptor could have an important role in extracellular matrix remodeling in several fibrosing disorders of kidney and heart. In this review we present the latest findings of the renin/prorenin receptor and its participation in fibrosing processes that may be relevant in the pathogenesis of idiopathic pulmonary fibrosis.

Garcia-Cegarra A.,Laboratorio Of Genetica | Merlo M.A.,Laboratorio Of Genetica | Ponce M.,Laboratorio Of Biologia Molecular | Portela-Bens S.,Laboratorio Of Genetica | And 3 more authors.
Cytogenetic and Genome Research | Year: 2013

This article presents the first physical mapping carried out in the Senegalese sole (Solea senegalensis), an important marine fish species of Southern Europe. Eight probes were designated to pick up genes of interest in aquaculture (candidate genes) from a bacterial artificial chromosome (BAC) library using a method of rapid screening based on a 4-dimension PCR. Seven known and 3 unknown clones were isolated and labeled. The 10 BAC clones were used as probes to map the karyotype of the species by fluorescence in situ hybridization (FISH). Nine out of the 10 clones were localized in only 1 chromosome pair, whereas the remaining one hybridized on 2 chromosome pairs. The 2-color FISH experiments showed colocation of 4 probes in 2 chromosome pairs. In addition, 2-color FISH was carried out both with 5S rDNA and the BAC containing the lysozyme gene published previously. This first genetic map of the Senegalese sole represents a starting point for future studies of the sole genome. In addition, 7 out of the 10 BAC clones were sequenced using next-generation sequencing, and bioinformatic characterization of the sequences was carried out. Hence the anchoring of the sequences to specific chromosomes or chromosome arms is now possible, leading to an initial scaffold of the Senegalese sole genome. © 2013 S. Karger AG, Basel.

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