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91.
Fernando Marqu��s-Garc��a Nuria Ferrandiz Rosal��a Fern��ndez-Alonso Laura Gonz��lez-Cano Marta Herreros-Villanueva Manuel Rosa-Garrido Bel��n Fern��ndez-Garc��a Jos�� P. Vaque Margarita M. Marqu��s Mar��a Eugenia Alonso Jos�� Carlos Segovia Javier Le��n Mar��a C. Mar��n 《The Journal of biological chemistry》2009,284(32):21139-21156
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García-Huante Yolanda Cayetano-Cruz Maribel Santiago-Hernández Alejandro Cano-Ramírez Claudia Marsch-Moreno Rodolfo Campos Jorge E. Aguilar-Osorio Guillermo Benitez-Cardoza Claudia G. Trejo-Estrada Sergio Hidalgo-Lara María Eugenia 《Extremophiles : life under extreme conditions》2017,21(1):175-186
Extremophiles - A hyperthermophilic and thermostable xylanase of 82 kDa (TtXynA) was purified from the culture supernatant of T. terrestris Co3Bag1, grown on carboxymethyl cellulose (CMC),... 相似文献
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Nancy Argüelles Eugenia Sánchez-Sandoval Aarón Mendieta Lourdes Villa-Tanaca Leticia Garduño-Siciliano Fabiola Jiménez María del Carmen Cruz José L. Medina-Franco Germán Chamorro-Cevallos Joaquín Tamariz 《Bioorganic & medicinal chemistry》2010,18(12):4238-4248
A series of α-asarone-based analogues was designed by conducting docking experiments with published crystal structures of human HMG-CoA reductase. Indeed, synthesis and evaluation of this series showed a highly hypocholesterolemic in vivo activity in a murine model, as predicted by previous docking studies. In agreement with this model, the polar groups attached to the benzene ring could play a key role in the enzyme binding and probably also in its biological activity, mimicking the HMG-moiety of the natural substrate. The hypolipidemic action mechanism of these compounds was investigated by developing a simple, efficient, and novel model for determining HMG-CoA reductase inhibition. The partial purification of the enzyme from Schizosaccharomyces pombe allowed for testing of α-asarone- and fibrate-based analogues, resulting in positive and significant inhibitory activity. 相似文献
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Maria Eugenia Teves Gobalakrishnan Sundaresan David J. Cohen Sharon L. Hyzy Illya Kajan Melissa Maczis Zhibing Zhang Richard M. Costanzo Jamal Zweit Zvi Schwartz Barbara D. Boyan Jerome F. Strauss III 《PloS one》2015,10(5)
Height is the result of many growth and development processes. Most of the genes associated with height are known to play a role in skeletal development. Single-nucleotide polymorphisms in the SPAG17 gene have been associated with human height. However, it is not clear how this gene influences linear growth. Here we show that a targeted mutation in Spag17 leads to skeletal malformations. Hind limb length in mutants was significantly shorter than in wild-type mice. Studies revealed differences in maturation of femur and tibia suggesting alterations in limb patterning. Morphometric studies showed increased bone formation evidenced by increased trabecular bone area and the ratio of bone area to total area, leading to reductions in the ratio of marrow area/total area in the femur. Micro-CTs and von Kossa staining demonstrated increased mineral in the femur. Moreover, osteocalcin and osterix were more highly expressed in mutant mice than in wild-type mice femurs. These data suggest that femur bone shortening may be due to premature ossification. On the other hand, tibias appear to be shorter due to a delay in cartilage and bone development. Morphometric studies showed reduction in growth plate and bone formation. These defects did not affect bone mineralization, although the volume of primary bone and levels of osteocalcin and osterix were higher. Other skeletal malformations were observed including fused sternebrae, reduced mineralization in the skull, medial and metacarpal phalanges. Primary cilia from chondrocytes, osteoblasts, and embryonic fibroblasts (MEFs) isolated from knockout mice were shorter and fewer cells had primary cilia in comparison to cells from wild-type mice. In addition, Spag17 knockdown in wild-type MEFs by Spag17 siRNA duplex reproduced the shorter primary cilia phenotype. Our findings disclosed unexpected functions for Spag17 in the regulation of skeletal growth and mineralization, perhaps because of its role in primary cilia of chondrocytes and osteoblasts. 相似文献
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María Eugenia Caba?a-Mu?oz José María Parmigiani-Izquierdo Luis Alberto Bravo-González Hee-Moon Kyung José Joaquín Merino 《PloS one》2015,10(6)
Background
The induction of oxidative stress by Hg can affect antioxidant enzymes. However, epidemiological studies have failed to establish clear association between dental fillings presence and health problems.Objectives
To determine whether heavy metals (in hair), antioxidant enzymes (SOD-1) and glutathione levels could be affected by the chronic presence of heavy metals in women who had dental amalgam fillings.Materials and Methods
55 hair samples (42 females with amalgam fillings and 13 female control subjects) were obtained. All subjects (mean age 44 years) who had dental amalgam filling for more than 10 years (average 15 years). Certain metals were quantified by ICP-MS (Mass Spectrophotometry) in hair (μg/g: Al, Hg, Ba, Ag, Sb, As, Be, Bi, Cd, Pb, Pt, Tl, Th, U, Ni, Sn, Ti) and SOD-1 and Glutathione (reduced form) levels in plasma. Data were compared with controls without amalgams, and analyzed to identify any significant relation between metals and the total number of amalgam fillings, comparing those with four or less (n = 27) with those with more than four (n = 15). As no significant differences were detected, the two groups were pooled (Amlgam; n = 42).Findings
Hg, Ag, Al and Ba were higher in the amalgam group but without significant differences for most of the heavy metals analyzed. Increased SOD-1 activity and glutathione levels (reduced form) were observed in the amalgam group. Aluminum (Al) correlated with glutathione levels while Hg levels correlated with SOD-1. The observed Al/glutathione and Hg/SOD-1 correlation could be adaptive responses against the chronic presence of mercury.Conclusions
Hg, Ag, Al and Ba levels increased in women who had dental amalgam fillings for long periods. Al correlated with glutathione, and Hg with SOD-1. SOD-1 may be a possible biomarker for assessing chronic Hg toxicity. 相似文献100.
The K1 antigen is an important virulence determinant of Escherichia coli strains and has been shown to be associated particularly with neonatal meningitis, bacteraemia and septicaemia. Thus, its detection seems to be useful, especially in the case of E. coli strains isolated from pregnant women and newborns. In this study, the sensitivity and specificity of the latex agglutination test (Pastorex Meningitis) for identification of E. coli serogroup K1 were assessed, using PCR as the gold standard. Our results showed that consistency of results between latex agglutination test and PCR amounted to 98.5 %. Therefore, Pastorex Meningitis is a good alternative to PCR and could be used for rapid K1 antigen detection, especially in local non-specialized laboratories with limited resources where PCR assay is not applied. 相似文献