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11.
Araceli Pérez-Vásquez Sofía Padilla-Mayne Ana Laura Martínez José S. Calderón Martha L. Macías-Rubalcava Rafael Torres-Colín Manuel Rangel-Grimaldo Rachel Mata 《化学与生物多样性》2021,18(8):e2100369
A decoction prepared from the aerial parts of Melampodium divaricatum showed antinociceptive and antihyperalgesic responses when tested in the formalin model in mice. From the CH2Cl2 fraction of the decoction, two non-previously reported secondary metabolites, 3-O-β-D-glucopyranosyl-16α-hydroxy-ent-kaurane ( 1 ) and melampodiamide ( 2 ) [(2′R*,4′Z)-2′-hydroxy-N-[(2S*,3S*,4R*)-1,3,4-trihydroxyoctadec-2-yl]tetracos-4-enamide] were separated and characterized by spectroscopic, spectrometric, and computational techniques. The flavonoids isoquercitrin and hyperoside, which possessed noted antinociceptive properties, were obtained from the active AcOEt fraction of the decoction. The chemical composition of the essential oil of the plant was also analyzed by gas chromatography-mass spectrometry. The major constituents were (E)-caryophyllene, germacrene D, β-elemene, δ-elemene, γ-patchoulene, and 7-epi-α-selinene. Headspace solid-phase microextraction analysis detected (E)-caryophyllene as the main volatile compound of the plant. 相似文献
12.
Managing Plant Resources: How Intensive Can it be? 总被引:3,自引:2,他引:1
Martha Sofía González-Insuasti Javier Caballero 《Human ecology: an interdisciplinary journal》2007,35(3):303-314
Previous studies have shown there is a wide spectrum of incipient management practices between gathering and agriculture,
that include resources commonly considered “wild.” Based on the study of 20 species used as foodstuffs in the community of
Santa María Tecomavaca (Mexico), we evaluated nonagricultural management forms such as gathering, incipient nonselective management,
incipient selective management and occasional ex situ cultivation to learn if they represent a gradient in the intensity of manipulation of a resource. The way in which the intensity
of manipulation of a resource can vary as a function of cultural importance and the species’ biology was also analyzed. Using
an index that measures the intensity of management of a resource, it has been established that the degree of intensity depends
on: the specialization of the practices directed to the environment as well as to the individuals; the number of persons performing
these practices; and the number of different practices taking place. The degree of management intensity is also a consequence
of the joint action of cultural importance and of species’ biology.
相似文献
Martha Sofía González-InsuastiEmail: |
13.
14.
Ana María Calderoni Verónica Biaggio Mariano Acosta Liliana Oliveros Fabian Mohamed María Sofía Giménez 《Biometals》2010,23(1):135-143
Cadmium (Cd) is widely used in industrial applications and is an important contaminant of agricultural products. As an endocrine
disruptor, Cd modifies the hormone release of pituitary anterior lobe (PAL). This work was undertaken to evaluate a possible
association between phospholipase D (PLD) and prolactin mRNA expressions and the activity of lactotrophs and folliculostellate
cells (FSC) in PAL of Cd exposed adult male Wistar rats (Cd, 0.133 mM per liter for 2 months). The PALs were submitted to
immunohistochemical and morphometric analysis to determine the percentage of lactotrophs (PRL-ir) and FSC (S-100-ir). Cultured
PAL cells were stained with Hoechst 33258 to determine the presence of alterations in nuclear morphology consistent with apoptosis.
The expressions of PLD and prolactin mRNA were assessed by RT-PCR. Cd treated rats showed a decrease of PLD mRNA levels that
can be associated to both high number of apoptotic cells and increase of S-100 protein expression in FSC. Cd decreased prolactin
mRNA expression, number of lactotrophs and percentage of PRL-ir suggesting a low availability of prolactin to be secreted
from PAL. Cd modifies the lactotrophs activity of pituitary gland through biochemical, genomic and morphological changes and
contributes directly or indirectly to the levels of serum prolactin. 相似文献
15.
Godoy A Ulloa V Rodríguez F Reinicke K Yañez AJ García Mde L Medina RA Carrasco M Barberis S Castro T Martínez F Koch X Vera JC Poblete MT Figueroa CD Peruzzo B Pérez F Nualart F 《Journal of cellular physiology》2006,207(3):614-627
It has been proposed that the enhanced metabolic activity of tumor cells is accompanied by an increased expression of facilitative hexose transporters (GLUTs). However, a previous immunohistochemical analysis of GLUT1 expression in 154 malignant human neoplasms failed to detect the GLUT1 isoform in 87 tumors. We used 146 normal human tissues and 215 tumor samples to reassess GLUT1 expression. A similar number of samples were used to compare the expression of GLUT2-6 and 9. The classical expression of GLUT1-5 in different normal human tissues was confirmed, however, we were unable to detect GLUT2 in human pancreatic islet cells. GLUT6 was principally detected in testis germinal cells and GLUT9 was localized in kidney, liver, heart, and adrenal. In tumor samples, GLUT1, 2, and 5 were the main transporters detected. GLUT1 was the most widely expressed transporter, however, 42% of the samples had very low-to-negative expression levels. GLUT2 was detected in 31% of the samples, being mainly expressed in breast, colon, and liver carcinoma. GLUT5 was detected in 27% of breast and colon adenocarcinoma, liver carcinoma, lymphomas, and testis seminoma samples. In situ RT-PCR and ultrastructural immunohistochemistry confirmed GLUT5 expression in breast cancer. GLUT6 and 9 are not clearly over-expressed in human cancer. The extensive expression of GLUT2 and 5 (glucose/fructose and fructose transporters, respectively) in malignant human tissues indicates that fructose may be a good energy substrate in tumor cells. Our functional data obtained in vitro in different tumor cells support this hypothesis. Additionally, these results suggest that fructose uptake could be used for positron emission tomography imaging and, may possibly represent a novel target for the development of therapeutic agents in different human cancers. 相似文献
16.
George Koutsoudakis Sofía Pérez-del-Pulgar Patricia González Gonzalo Crespo Miquel Navasa Xavier Forns 《PloS one》2012,7(12)
Robust replication of hepatitis C virus (HCV) in cell culture occurs only with the JFH-1 (genotype 2a) recombinant genome. The aim of this study was to develop a system for HCV infection quantification analysis and apply it for the selection of patient sera that may contain cell culture infectious viruses, particularly of the most clinically important genotype 1. Initially, a hepatoma cell line (designated Huh-7.5/EG(4A/4B)GLuc) was generated that stably expressed the enhanced green fluorescent protein (EGFP) fused in-frame to the secreted Gaussia luciferase via a recognition sequence of the viral NS3/4A protease. Upon HCV infection, NS3/4A cleaved at its signal and the Gaussia was secreted to the culture medium, thus facilitating the infection quantification. The Huh-7.5/EG(4A/4B)GLuc cell line provided a rapid and highly sensitive quantification of HCV infection in cell culture using JFH-1-derived viruses. Furthermore, the Huh-7.5/EG(4A/4B)GLuc cells were also shown to be a suitable host for the discovery of anti-HCV inhibitors by using known compounds that target distinct stages of the HCV life cycle; the Ź-factor of this assay ranged from 0.72 to 0.75. Additionally, eighty-six sera derived from HCV genotype 1b infected liver transplant recipients were screened for their in vitro infection and replication potential. Approximately 12% of the sera contained in vitro replication-competent viruses, as deduced by the Gaussia signal, real time quantitative PCR, immunofluorescence and capsid protein secretion. We conclude that the Huh-7.5/EG(4A/4B)GLuc cell line is an excellent system not only for the screening of in vitro replication-competent serum-derived viruses, but also for the subsequent cloning of recombinant isolates. Additionally, it can be utilized for high-throughput screening of antiviral compounds. 相似文献
17.
Melisa A. Conde Natalia P. Alza Pablo A. Iglesias González Paola G. Scodelaro Bilbao Sofía Sánchez Campos Romina M. Uranga Gabriela A. Salvador 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2018,1863(6):639-650
We have previously shown that phospholipase D (PLD) pathways have a role in neuronal degeneration; in particular, we found that PLD activation is associated with synaptic injury induced by oxidative stress. In the present study, we investigated the effect of α-synuclein (α-syn) overexpression on PLD signaling. Wild Type (WT) α-syn was found to trigger the inhibition of PLD1 expression as well as a decrease in ERK1/2 phosphorylation and expression levels. Moreover, ERK1/2 subcellular localization was shown to be modulated by WT α-syn in a PLD1-dependent manner. Indeed, PLD1 inhibition was found to alter the neurofilament network and F-actin distribution regardless of the presence of WT α-syn. In line with this, neuroblastoma cells expressing WT α-syn exhibited a degenerative-like phenotype characterized by a marked reduction in neurofilament light subunit (NFL) expression and the rearrangement of the F-actin organization, compared with either the untransfected or the empty vector-transfected cells. The gain of function of PLD1 through the overexpression of its active form had the effect of restoring NFL expression in WT α-syn neurons. Taken together, our findings reveal an unforeseen role for α-syn in PLD regulation: PLD1 downregulation may constitute an early mechanism in the initial stages of WT α-syn-triggered neurodegeneration. 相似文献
18.
Darío E. Manzoli María J. Saravia-Pietropaolo Leandro R. Antoniazzi Emilce Barengo Sofía I. Arce Martín A. Quiroga Pablo M. Beldomenico 《International journal for parasitology》2018,48(6):445-455
Hosts counteract infections using two distinct defence strategies, resistance (reduction in pathogen fitness) and tolerance (limitation of infection damage). These strategies have been minimally investigated in multi-host systems, where they may vary across host species, entailing consequences both for hosts (virulence) and parasites (transmission). Comprehending the interplay among resistance, tolerance, virulence and parasite success is highly relevant for our understanding of the ecology and evolution of infectious and parasitic diseases. Our work investigated the interaction between an insect parasite and its most common bird host species, focusing on two relevant questions: (i) are defence strategies different between main and alternative hosts and, (ii) what are the consequences (virulence and parasite success) of different defence strategies? We conducted a matched field experiment and longitudinal studies at the host and the parasite levels under natural conditions, using a system comprising Philornis torquans flies and three bird hosts – the main host and two of the most frequently used alternative hosts. We found that main and alternative hosts have contrasting defence strategies, which gave rise in turn to contrasting virulence and parasite success. In the main bird host, minor loss of fitness, no detectable immune response, and high parasite success suggest a strategy of high tolerance and negligible resistance. Alternative hosts, on the contrary, resisted by mounting inflammatory responses, although with very different efficiency, which resulted in highly dissimilar parasite success and virulence. These results show clearly distinct defence strategies between main and alternative hosts in a natural multi-host system. They also highlight the importance of defence strategies in determining virulence and infection dynamics, and hint that defence efficiency is a crucial intervening element in these processes. 相似文献
19.
Arantxa Palacín Cristina Gómez-Casado Luis A. Rivas Jacobo Aguirre Leticia Tordesillas Joan Bartra Carlos Blanco Teresa Carrillo Javier Cuesta-Herranz Consolación de Frutos Genoveva García álvarez-Eire Francisco J. Fernández Pedro Gamboa Rosa Mu?oz Rosa Sánchez-Monge Sofía Sirvent María J. Torres Susana Varela-Losada Rosalía Rodríguez Victor Parro Miguel Blanca Gabriel Salcedo Araceli Díaz-Perales 《PloS one》2012,7(12)
The study of cross-reactivity in allergy is key to both understanding. the allergic response of many patients and providing them with a rational treatment In the present study, protein microarrays and a co-sensitization graph approach were used in conjunction with an allergen microarray immunoassay. This enabled us to include a wide number of proteins and a large number of patients, and to study sensitization profiles among members of the LTP family. Fourteen LTPs from the most frequent plant food-induced allergies in the geographical area studied were printed into a microarray specifically designed for this research. 212 patients with fruit allergy and 117 food-tolerant pollen allergic subjects were recruited from seven regions of Spain with different pollen profiles, and their sera were tested with allergen microarray. This approach has proven itself to be a good tool to study cross-reactivity between members of LTP family, and could become a useful strategy to analyze other families of allergens. 相似文献
20.
Les Francisco Cásedas Guillermo Gómez Carlota Moliner Cristina Valero Marta Sofía López Víctor 《Journal of physiology and biochemistry》2021,77(1):109-131
Journal of Physiology and Biochemistry - Diabetes mellitus is a chronic metabolic disease characterized by high blood glucose concentration. Nowadays, type 2 diabetes or insulin resistant diabetes... 相似文献