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51.
Eva Venegas‐Moreno Alvaro Flores‐Martinez Elena Dios Mari C. Vazquez‐Borrego Alejandro Ibaez‐Costa Ainara Madrazo‐Atutxa Miguel A. Japn Justo P. Castao Raúl M. Luque David A. Cano Alfonso Soto‐Moreno 《Journal of cellular and molecular medicine》2019,23(5):3088-3096
Acromegaly is a rare disease resulting from hypersecretion of growth hormone (GH) and insulin‐like growth factor 1 (IGF1) typically caused by pituitary adenomas, which is associated with increased mortality and morbidity. Somatostatin analogues (SSAs) represent the primary medical therapy for acromegaly and are currently used as first‐line treatment or as second‐line therapy after unsuccessful pituitary surgery. However, a considerable proportion of patients do not adequately respond to SSAs treatment, and therefore, there is an urgent need to identify biomarkers predictors of response to SSAs. The aim of this study was to examine E‐cadherin expression by immunohistochemistry in fifty‐five GH‐producing pituitary tumours and determine the potential association with response to SSAs as well as other clinical and histopathological features. Acromegaly patients with tumours expressing low E‐cadherin levels exhibit a worse response to SSAs. E‐cadherin levels are associated with GH‐producing tumour histological subtypes. Our results indicate that the immunohistochemical detection of E‐cadherin might be useful in categorizing acromegaly patients based on the response to SSAs. 相似文献
52.
Anil Chekuri Katarzyna Zientara‐Rytter Angel Soto‐Hermida Shyamanga Borooah Marina Voronchikhina Pooja Biswas Virender Kumar David Goodsell Caroline Hayward Peter Shaw Chloe Stanton Donita Garland Suresh Subramani Radha Ayyagari 《Aging cell》2019,18(6)
Late‐onset retinal degeneration (L‐ORD) is an autosomal dominant macular degeneration characterized by the formation of sub‐retinal pigment epithelium (RPE) deposits and neuroretinal atrophy. L‐ORD results from mutations in the C1q‐tumor necrosis factor‐5 protein (CTRP5), encoded by the CTRP5/C1QTNF5 gene. To understand the mechanism underlying L‐ORD pathology, we used a human cDNA library yeast two‐hybrid screen to identify interacting partners of CTRP5. Additionally, we analyzed the Bruch's membrane/choroid (BM‐Ch) from wild‐type (Wt), heterozygous S163R Ctrp5 mutation knock‐in (Ctrp5S163R/wt), and homozygous knock‐in (Ctrp5S163R/S163R) mice using mass spectrometry. Both approaches showed an association between CTRP5 and HTRA1 via its C‐terminal PDZ‐binding motif, stimulation of the HTRA1 protease activity by CTRP5, and CTRP5 serving as an HTRA1 substrate. The S163R‐CTRP5 protein also binds to HTRA1 but is resistant to HTRA1‐mediated cleavage. Immunohistochemistry and proteomic analysis showed significant accumulation of CTRP5 and HTRA1 in BM‐Ch of Ctrp5S163R/S163R and Ctrp5S163R/wt mice compared with Wt. Additional extracellular matrix (ECM) components that are HTRA1 substrates also accumulated in these mice. These results implicate HTRA1 and its interaction with CTRP5 in L‐ORD pathology. 相似文献
53.
Juan M. Soto Alicia Mas Jos A. Rodrigo Tatiana Alieva Gustavo Domínguez‐Bernal 《Journal of biophotonics》2019,12(9)
In this work, we report the use of refractive index (RI) tomography for quantitative analysis of unstained DH82 cell line infected with Leishmania infantum. The cell RI is reconstructed by using a modality of optical diffraction tomography technique that employs partially coherent illumination, thus enabling inherent compatibility with conventional wide‐field microscopes. The experimental results demonstrate that the cell dry mass concentration (DMC) obtained from the RI allows for reliable detection and quantitative characterization of the infection and its temporal evolution. The RI provides important insight for studying morphological changes, particularly membrane blebbing linked to an apoptosis (cell death) process induced by the disease. Moreover, the results evidence that infected DH82 cells exhibit a higher DMC than healthy samples. These findings open up promising perspectives for clinical diagnosis of Leishmania. 相似文献
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The study of current distribution patterns of amphibian species in South America is of particular interest in areas such as evolutionary ecology and conservation biology. These patterns could be playing an important role in biological interactions, population size, and connectivity, and potential extinction risk in amphibians. Here, we tested the effects of spatial and environmental factors on the variation, turnover, and phylogenetic diversity of anuran amphibian species in tropical forests of western Ecuador. Data for presence/absence of 101 species of 34 genera and 10 families registered in 12 sites (nested in four biogeographic units) were obtained through fieldwork, museum collections, and literature records. We examined the influence of geographical, altitudinal, temperature, and precipitation distances on differences in anuran composition between sites. We found significant positive correlations among all of these variables with anuran distribution. The greatest alpha diversity (species richness) was found in the Equatorial Chocó biogeographic unit. Equatorial Pacific biogeographic unit could act as a transition zone between the Equatorial Chocó and Equatorial Tumbes. The western Andes (Western Cordillera biogeographic unit) was the most dissimilar and exhibited a higher species turnover rate than the other biogeographic units. Our results suggest that precipitation and elevation play a key role in maintaining the diversity of amphibian species in western Ecuador. 相似文献
56.
Eduardo Estrada José A Villarreal César Cantú Ismael Cabral Laura Scott Carmen Yen 《Journal of ethnobiology and ethnomedicine》2007,3(1):1-8
The archives of Flora Medicinal, an ancient pharmaceutical laboratory that supported ethnomedical research in Brazil for more than 30 years, were searched for plants with antimalarial use. Forty plant species indicated to treat malaria were described by Dr. J. Monteiro da Silva (Flora Medicinal leader) and his co-workers. Eight species, Bathysa cuspidata, Cosmos sulphureus, Cecropia hololeuca, Erisma calcaratum, Gomphrena arborescens, Musa paradisiaca, Ocotea odorifera, and Pradosia lactescens, are related as antimalarial for the first time in ethnobotanical studies. Some species, including Mikania glomerata, Melampodium divaricatum, Galipea multiflora, Aspidosperma polyneuron, and Coutarea hexandra, were reported to have activity in malaria patients under clinical observation. In the information obtained, also, there were many details about the appropriate indication of each plant. For example, some plants are indicated to increase others' potency. There are also plants that are traditionally employed for specific symptoms or conditions that often accompany malaria, such as weakness, renal failure or cerebral malaria. Many plants that have been considered to lack activity against malaria due to absence of in vitro activity against Plasmodium can have other mechanisms of action. Thus researchers should observe ethnomedical information before deciding which kind of screening should be used in the search of antimalarial drugs. 相似文献
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58.
de Jesus Santana Mayla Barbosa-Júnior Sebastião Martins Dias Lana Laene Lima Silva Lázara Aline Simões da Silva Givanildo Zildo Fortini Evandro Alexandre Batista Diego Silva Otoni Wagner Campos da Costa Netto Antônio Paulino Rocha Diego Ismael 《In vitro cellular & developmental biology. Plant》2022,58(6):865-875
In Vitro Cellular & Developmental Biology - Plant - The aim of this study was to establish a system of in vitro germination and propagation of Guazuma ulmifolia Lam. microcuttings (Malvaceae).... 相似文献
59.
José Romo-Yáñez Mauricio Domínguez-Castro Josiff S. Flores-Reyes Higinio Estrada-Juárez Ismael Mancilla-Herrera Jessica Hernández-Pineda María Luisa Bazan-Tejeda Mónica Aguinaga-Ríos Enrique Reyes-Muñoz 《Biochemical and biophysical research communications》2019,508(4):1149-1154
Diabetes in pregnancy constitutes an unfavorable environment for embryonic and fetal development, where the child has a higher risk of perinatal morbidity and mortality, with high incidence of congenital malformations and predisposition to long-term metabolic diseases that increase with a hypercaloric diet. To analyze whether hyperglycemia differentially affects proliferation, apoptosis, and mRNA expression in cells from children of normoglycemic pregnancies (NGPs) and diabetes mellitus pregnancies (DMPs), we used umbilical cord Wharton jelly cells as a research model. Proliferation assays were performed to analyze growth and determine the doubling time, and the rate of apoptosis was determined by flow cytometry-annexin-V assays. AMPK, BNIP3, HIF1α, and p53 mRNA gene expression was assessed by semi-quantitative RT-PCR. We found that hyperglycemia decreased proliferation in a statistically significant manner in NGP cells treated with 40?mM D-glucose and in DMP cells treated with 30 and 40?mM D-glucose. Apoptosis increased in hyperglycemic conditions in NGP and DMP cells. mRNA expression of BNIP3 and p53 was significantly increased in cells from DMPs but not in cells from NGPs. We found evidence that maternal irregular metabolic conditions, like diabetes with hyperglycemia in culture, affect biological properties of fetal cells. These observations could be a constituent of fetal programming. 相似文献
60.