32 research outputs found

    Origem e diversidade clonal do lagarto partenogenético Aspidoscelis rodecki (Squamata: Teiidae): evidências cromossômicas.

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    Com a finalidade de investigar a origem e a diversidadecromossômica de Aspidoscelis rodecki, analisamos os cariótipos de indivíduos de duas populações diferentes desse lagarto unissexual. O cariótipo de A. rodecki possui um número diplóide de 50 cromossomos e exibe um heteromorfismo estrutural marcante. O arranjo cromossômico parece ter sido originado pela fissão de Todd após o surgimento da partenogênese (hibridização entre A. angusticeps e A. deppii). Esse padrão foi observado em duas populações da espécie, que é endêmica da Península de Yucatán.We analyzed the karyotypes of individuals of two different populations of Aspidoscelis rodecki to investigate the origin andchromosomal diversity of this unisexual lizard. The karyotype of A. rodecki has a diploid number of 50 chromosomes, and exhibits a marked structural heteromorphism. The unique arrangement seems to have originated by Todd´s fission after the origin of parthenogenesis (hybridization between A. angusticeps and A. deppii). This pattern was observed in two populations of the species, which is endemic to the Yucatan Peninsula.Con el fin de conocer el origen y la diversidad cromosómica deAspidoscelis rodecki, analizamos el cariotipo de individuos de dos poblaciones de esta lagartija unisexual. El cariotipo de A. rodecki presenta un número diploide de 50 cromosomas y muestra unmarcado heteromorfismo estructural. El arreglo cromosómico parece haberse originado a través de fisiones de Todd, posteriores al origen de la partenogénesis (hibridación entre A. angusticeps y A. deppii). Este patrón fue observado en dos poblaciones de la especie, que es endémica de la Península de Yucatán

    Spatially resolved properties of the ionized gas in the H II galaxy J084220+115000

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    We present a spatially resolved spectroscopic study for the metal poor H II galaxy J084220+115000 using MEGARA Integral Field Unit observations at the Gran Telescopio Canarias. We estimated the gas metallicity using the direct method for oxygen, nitrogen, and helium and found a mean value of 12 + log (O/H) = 8.03 ± 0.06, and integrated electron density and temperature of ∼161 cm−3 and ∼15400 K, respectively. The metallicity distribution shows a large range of Δ(O/H) = 0.72 dex between the minimum and maximum (7.69 ± 0.06 and 8.42 ± 0.05) values, unusual in a dwarf star-forming galaxy. We derived an integrated log (N/O) ratio of −1.51 ± 0.05 and found that both N/O and O/H correspond to a primary production of metals. Spatially resolved maps indicate that the gas appears to be photoionized by massive stars according to the diagnostic line ratios. Between the possible mechanisms to explain the starburst activity and the large variation of oxygen abundance in this galaxy, our data support a possible scenario where we are witnessing an ongoing interaction triggering multiple star-forming regions localized in two dominant clumps. © 2023 The Author(s) Published by Oxford University Press on behalf of Royal Astronomical Society.DFA work is funded by a Consejo Nacional de Ciencia y Tecnología (CONACyT, Mexico) grant through project A1-S-22784. This publication is based on data obtained with the MEGARA instrument at the GTC, installed in the Spanish Observatorio del Roque de los Muchachos, in the island of La Palma. MEGARA has been built by a Consortium led by the Universidad Complutense de Madrid (Spain) and that also includes the Instituto de Astrofísica, Optica y Electrónica (INAOE, Mexico), Instituto de Astrofísica de Andalucía (CSIC, Spain), and the Universidad Politécnica de Madrid (Spain). This work is based on data obtained with the MEGARA instrument, funded by European Regional Development Funds (ERDF), through the Programa Operativo Canarias FEDER 2014–2020. YDM thanks CONACYT for the research grant CB-A1-S-25070 and DRG for the research grant CB-A1-S-22784 from which the postdoctoral grant that supported DFA was obtained. RC also thanks CONACyT for the research grant CF2022-320152. RA acknowledges support from ANID Fondecyt Regular 1202007. ALGM acknowledges support from the Spanish Ministry of Science and Innovation, project PID2019-107408GB-C43 (ESTALLIDOS), and from Gobierno de Canarias through EU FEDER funding, project PID2020010050. JMA acknowledges the support of the Viera y Clavijo Senior program funded by ACIISI and ULL. JIP acknowledges financial support from projects Estallidos6 AYA2016-79724-C4 (Spanish Ministerio de Economia y Competitividad), Estallidos7 PID2019-107408GB-C44 (Spanish Ministerio de Ciencia e Innovacion), grant P18-FR-2664 (Junta de Andalucía), and grant SEV-2017-0709 ‘Center of Excellence Severo Ochoa Program’ (State Agency for Research of the Spanish MCIU).With funding from the Spanish government through the "Severo Ochoa Centre of Excellence" accreditation (CEX2021-001131-S).Peer reviewe

    CIBERER : Spanish national network for research on rare diseases: A highly productive collaborative initiative

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    Altres ajuts: Instituto de Salud Carlos III (ISCIII); Ministerio de Ciencia e Innovación.CIBER (Center for Biomedical Network Research; Centro de Investigación Biomédica En Red) is a public national consortium created in 2006 under the umbrella of the Spanish National Institute of Health Carlos III (ISCIII). This innovative research structure comprises 11 different specific areas dedicated to the main public health priorities in the National Health System. CIBERER, the thematic area of CIBER focused on rare diseases (RDs) currently consists of 75 research groups belonging to universities, research centers, and hospitals of the entire country. CIBERER's mission is to be a center prioritizing and favoring collaboration and cooperation between biomedical and clinical research groups, with special emphasis on the aspects of genetic, molecular, biochemical, and cellular research of RDs. This research is the basis for providing new tools for the diagnosis and therapy of low-prevalence diseases, in line with the International Rare Diseases Research Consortium (IRDiRC) objectives, thus favoring translational research between the scientific environment of the laboratory and the clinical setting of health centers. In this article, we intend to review CIBERER's 15-year journey and summarize the main results obtained in terms of internationalization, scientific production, contributions toward the discovery of new therapies and novel genes associated to diseases, cooperation with patients' associations and many other topics related to RD research

    Genetic homogeneity between two populations of the parthenogenetic lizard Aspidoscelis cozumela Homogeneidad genética entre dos poblaciones de la lagartija partenogenética Aspidoscelis cozumela

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    We used skin-grafting to assess the genetic variability between 2 populations of the parthenogenetic lizard Aspidoscelis cozumela. We transplanted 238 skin fragments among individuals of 2 coastal populations at Cozumel Island. Grafts belonging to individuals that survive more than 60 days suggested genetic homogeneity between both populations, consistent with the existence of only 1 clone within this unisexual species.<br>Se utilizó el método de transplantes de piel para evaluar la variabilidad genética entre 2 poblaciones de la lagartija partenogenética Aspidoscelis cozumela. Se transplantaron 238 fragmentos de piel entre individuos de 2 poblaciones costeras de Isla Cozumel. Los transplantes pertenecientes a individuos que vivieron más de 60 días, mostraron homogeneidad genética entre ambas poblaciones, lo cual sugiere la existencia de 1 sólo clon dentro de esta especie unisexual

    Anatomical cardiac alterations in liver cirrhosis: An autopsy study

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    Background. It has been suggested that liver cirrhosis (LC), regardless of etiology, may be associated with anatomical cardiac alterations.Objective. To describe the frequency and type of macroscopical anatomic cardiac abnormalities present in alcoholic and non-alcoholic cirrhotic patients in an autopsy series.Material and methods. The autopsy records performed at our institution during a 12-year period (1990-2002) were reviewed. All cases with final diagnosis of LC were included, their demographic characteristics as well as cirrhosis etiology and macroscopic anatomical cardiac abnormalities (MACA) analyzed. Patients with any known history of heart disease prior to diagnosis of cirrhosis were excluded.Results. A total of 1,176 autopsies were performed, of which 135 cases (11.5%) were patients with LC. Two patients with cardiac cirrhosis were excluded. Chronic alcohol abuse (29%) and chronic hepatitis due to hepatitis C virus (HCV) infection (20%) were the most common causes of cirrhosis. The etiology was not identified in 35% of the cases, even after exhaustive clinical, serological and/or radiological assessment. In the postmortem analysis, 43% of the cases were informed to have MACA (47% in the group of patients with alcoholic cirrhosis and 41% in other types of cirrhosis); this rate increased to 62% in patients with ascites. The most frequent alterations were cardiomegaly and left ventricular hypertrophy (LVH).Conclusion. The results confirm the high frequency of cardiac abnormalities in patients with cirrhosis, regardless of cirrhosis etiology

    Advanced-stage mycosis fungoides: role of the signal transducer and activator of transcription 3, nuclear factor-kB and nuclear factor of activated T cells pathways

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    BACKGROUND: The malignant mechanisms that control the development of cutaneous T-cell lymphoma (CTCL) are beginning to be identified. Recent evidence suggests that disturbances in specific intracellular signalling pathways, such as RAS-mitogen-activated protein kinase, T-cell receptor (TCR)-phospholipase C gamma 1 (PLCG1)-nuclear factor of activated T cells (NFAT) and Janus kinase (JAK)-signal transducer and activator of transcription (STAT), may play an essential role in the pathogenesis of CTCL. OBJECTIVES: To investigate the mechanisms controlling disease development and progression in mycosis fungoides (MF), the most common form of CTCL. METHODS: We collected 100 samples that were submitted for diagnosis of, or a second opinion regarding, MF between 2001 and 2018, 80% of which were in the early clinical stages of the disease. Formalin-fixed paraffin-embedded tissues were used for histological review and to measure the expression by immunohistochemistry of surrogate markers of activation of the TCR-PLCG1-NFAT, JAK-STAT and NF-?B pathways. Folliculotropism and large-cell transformation were also examined. RESULTS: NFAT and nuclear factor kappa B (NF-?B) markers showed a comparable activation status in early and advanced stages, while STAT3 activation was more frequent in advanced stages and was associated with large-cell transformation. Consistently with this observation, STAT3 activation occurred in parallel with MF progression in two initially MF-negative cases. A significant association of NFAT with NF-?B markers was also found, reflecting a common mechanism of activation in the two pathways. Genomic studies identified nine mutations in seven genes known to play a potential role in tumorigenesis in T-cell leukaemia/lymphoma, including PLCG1, JAK3 and STAT3, which underlies the activation of these key cell-survival pathways. A higher mutational allele frequency was detected in advanced stages. CONCLUSIONS: Our results show that STAT3 is activated in advanced cases and is associated with large-cell transformation, while the activation of NFAT and NF-?B is maintained throughout the disease. These findings could have important diagnostic and therapeutic implications. What's already known about this topic? Mycosis fungoides is characterized by a clonal expansion of T cells in the skin. The mechanisms controlling disease development and progression are not fully understood. What does this study add? An association of the nuclear factor of activated T cells and nuclear factor kappa B pathways was found, which could reflect a common mechanism of activation. These pathways were activated in early and advanced stages at the same level. Signal transducer and activator of transcription 3 activation was associated with large-cell transformation and was more frequent in advanced stages. A genomic analysis of cutaneous T-cell lymphoma-associated genes was performed. Nine mutations were detected. What is the translational message? These results could have important implications for the treatment of MF in the near future.Funding: This study has been supported by grants from the Instituto de Salud Carlos III, from the Ministerio de Economía, Industria y Competitividad (SAF2013-47416-R, CIBERONC-ISCIII, ISCIII-MINECO-AES-FEDER (Plan Estatal I + D + I 2013–2016): PI14/00221, PIE14/0064, PIE15/0081, PIE16/01294, and FIS 17/0957)), Asociación española contra el Cáncer (AECC), Comunidad Autónoma de Madrid and from the Instituto Formación e Investigación Hospital Universitario Marqués de Valdecilla (IDIVAL): NVAL16/18

    Genetic diversity of HLA system in three populations from Chihuahua, Mexico: Chihuahua City, Ciudad Juárez and rural Chihuahua

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    We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) alleles by PCR-SSP based typing in 461 Mexicans from the state of Chihuahua living in Chihuahua city (N = 119), Ciudad Juárez (N = 106) and rural communities (N = 236), to obtain information regarding allelic and haplotypic frequencies and their linkage disequilibrium. We find that the most frequent haplotypes found in the state of Chihuahua include seven Native American and three European haplotypes. Admixture estimates revealed that the main genetic components in Chihuahua are European (52.12 ± 0.88 by ML; 41.53 of European haplotypes) and Native American (39.51 ± 2.17 by ML; 37.45 of Native American haplotypes), while African genetic component was less apparent (8.36 ± 1.47 by ML; 11.70 of African haplotypes)
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