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1.
Genetica ; 147(2): 149-164, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30879155

RESUMO

Land use changes are threatening the maintenance of biodiversity. Genetic diversity is one of the main indicators of biological diversity and is highly important as it shapes the capability of populations to respond to environmental changes. We studied eleven populations of Pseudoeurycea robertsi, a micro-endemic and critically endangered species from the Nevado de Toluca Volcano, a mountain that is part of the Trans-Mexican Volcanic Belt, Mexico. We sequenced the mitochondrial cytochrome b gene from 71 individuals and genotyped 9 microsatellites from 150 individuals. Our results based on the cytochrome b showed two divergent lineages, with moderate levels of genetic diversity and a recently historical demographic expansion. Microsatellite-based results indicated low levels of heterozygosity for all populations and few alleles per locus, as compared with other mole salamander species. We identified two genetically differentiated subpopulations with a significant level of genetic structure. These results provide fundamental data for the development of management plans and conservation efforts for this critically endangered species.


Assuntos
Espécies em Perigo de Extinção , Polimorfismo Genético , Urodelos/genética , Animais , Ecossistema , Repetições de Microssatélites
2.
J La State Med Soc ; 164(1): 21-5, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22533109

RESUMO

Pleomorphic sarcoma, widely known as malignant fibrous histiocytoma (MFH), is a soft tissue sarcoma. The occurrence of this malignancy in the mediastinum is rare. To our knowledge, only 13 cases of MFH of the mediastinum have been previously reported. Furthermore, only three cases of MFH in patients infected with human immunodeficiency virus (HIV) have been previously described. Here we present a 44-year-old African-American male who complained of epigastric pain radiating to the right chest. On admission, a chest radiograph revealed a widened mediastinum, and chest computerized tomography (CT) identified a large mass in the posterior mediastinum. Histologic diagnosis revealed a high-grade MFH. He was also incidentally diagnosed with HIV infection. The rarity of this malignancy and uncommon site of presentation in association with an immunodeficient state makes this case unique. This is the first report in the literature of an HIV-infected patient presenting with this uncommon tumor in the mediastinum.


Assuntos
Infecções por HIV/complicações , Histiocitoma Fibroso Maligno , Neoplasias do Mediastino , Mediastino/patologia , Adulto , Biópsia por Agulha , Broncoscopia/métodos , Histiocitoma Fibroso Maligno/complicações , Histiocitoma Fibroso Maligno/patologia , Histiocitoma Fibroso Maligno/fisiopatologia , Histiocitoma Fibroso Maligno/terapia , Cuidados Paliativos na Terminalidade da Vida , Humanos , Masculino , Neoplasias do Mediastino/complicações , Neoplasias do Mediastino/patologia , Neoplasias do Mediastino/fisiopatologia , Neoplasias do Mediastino/terapia , Gradação de Tumores , Metástase Neoplásica , Estadiamento de Neoplasias , Tomografia Computadorizada por Raios X/métodos
3.
BioTech (Basel) ; 11(2)2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35822784

RESUMO

Mammary gland secretory cells produce miRNA-rich milk. In humans, these miRNAs reach infant/neonate bloodstream, playing diverse roles, like neural system development, metabolism, and immune system maturation. Notwithstanding, still few works explore human milk miRNA content, and there are no reports at the population level. Our hypothesis was that miR-146b-5p, miR148a-3p, miR155-5p, mir181a-5p, and mir200a-3p immunoregulatory miRNAs are expressed in human colostrum/milk at a higher level than infant milk formulae. The aim of this work was to evaluate the expression of the five immunoregulatory miRNAs in human milk and compare it with their expression in infant milk formula. For this purpose, miRNA relative expression was measured by qPCR in cDNA prepared from total RNA extracted from sixty human colostrum/milk samples and six different formulae. The comparative Cт method 2-ΔCт using exogenous cel-miR-39 as internal control was employed, followed by statistical analysis. We found the relative expression levels of miRNAs are comparable among colostrum/milk samples, and these miRNAs are present in infant milk formulae but at very low concentrations. We conclude that the relative expression of the immunomodulatory miRNAs is comparable in all the human colostrum/milk samples and is higher than the expression in formulae.

4.
Talanta ; 96: 89-95, 2012 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-22817933

RESUMO

The paper presents application of multiwall carbon nanotubes (MWCNTs) modified with 5-dodecylsalicylaldoxime to copper(II) flow-injection on-line preconcentration and flame atomic absorption spectrometric (FAAS) determination. Two new sorbents were obtained by impregnation of MWCNTs with Cu(II)-LIX 622(®) complex, however in the first case modification was preceded by carbon wall activation via oxidization (Cu-LIX-CNT-A sorbent), and in the second one no surface activation was performed (Cu-LIX-CNT sorbent). It was found that effective leaching of initially introduced copper and Cu(II) retained in preconcentration process could be realized with the use 7% and 5% (v/v) nitric acid, for particular sorbents. Testing the influence of loading solution pH and rate of loading on sorption it was found out that optimal range of loading solution pH was about 4.5-6.3 for activated and 6.15-6.25 for non-activated CNT. Investigation of sorption kinetics showed that the process can be described by pseudo-second order reaction model. Sorption equilibrium conditions (90% sorption) for LIX-CNT-A and LIX-CNT were obtained after 8-15min, respectively and maximum sorption capacity for the new sorbents amounted to 18.1mgg(-1) and 31.6mgg(-1), respectively. For the examined sorbents enrichment factors increased with extension of loading time up to 180s: linearly for activated and non-linearly for non-activated MWCNTs. Influence of potential interferents such as Cd(II), Zn(II), Fe(III), Mg(II) and Ca(II) ions on copper(II) sorption on the new CNT materials was examined individually and with the use of 2(5-2) factorial design. The study revealed significant interference from iron, magnesium and calcium ions at relatively high concentrations. Applicability of the proposed sorbents was tested for Cu(II) determination in various kinds of water samples and the results were compared with those obtained with the use of ICP MS as a reference technique. Copper(II) determination in two certified reference materials: waste water (EU-H-3) and ground (ES-H-2) water was performed in order to assess trueness of the evaluated preconcentration procedures. Satisfactory values of relative errors were obtained for both procedures.

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