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51.
Detection of a soluble serum antigen by a new monoclonal antibody ED8 in patients with breast cancer
M Mortada G Pancino C Charpin M H Schlageter F Calvo A Roseto 《Comptes rendus de l'Académie des sciences. Série III, Sciences de la vie》1990,311(2):63-68
A murine hybridoma, secreting monoclonal antibody ED8, was generated by immunization with the breast cancer cell line H466B. ED8 reacts with a 300 kDa antigen present on H466B cell surface. The antigen can be detected in serum from breast cancer patients, using ELISA and immunoblotting. 相似文献
52.
Iris M Costa Tallybia HT Nasser Marilene Demasi Rafaella MP Nascimento Luis ES Netto Sayuri Miyamoto Fernanda M Prado Gisele Monteiro 《BMC microbiology》2011,11(1):268
Background
The gene YCL047C, which has been renamed promoter of filamentation gene (POF1), has recently been described as a cell component involved in yeast filamentous growth. The objective of this work is to understand the molecular and biological function of this gene.Results
Here, we report that the protein encoded by the POF1 gene, Pof1p, is an ATPase that may be part of the Saccharomyces cerevisiae protein quality control pathway. According to the results, Δpof1 cells showed increased sensitivity to hydrogen peroxide, tert-butyl hydroperoxide, heat shock and protein unfolding agents, such as dithiothreitol and tunicamycin. Besides, the overexpression of POF1 suppressed the sensitivity of Δpct1, a strain that lacks a gene that encodes a phosphocholine cytidylyltransferase, to heat shock. In vitro analysis showed, however, that the purified Pof1p enzyme had no cytidylyltransferase activity but does have ATPase activity, with catalytic efficiency comparable to other ATPases involved in endoplasmic reticulum-associated degradation of proteins (ERAD). Supporting these findings, co-immunoprecipitation experiments showed a physical interaction between Pof1p and Ubc7p (an ubiquitin conjugating enzyme) in vivo.Conclusions
Taken together, the results strongly suggest that the biological function of Pof1p is related to the regulation of protein degradation.53.
The structural pattern of the pineal gland in the hen corresponds to a more advanced stage of the evolution which began in an early period of the animal's life. This evolution corresponds mainly to the transformation of the large follicular cavities into cellular 'rosettes'. The parafollicular layer disappears from the rosette wall which thus remains with only one row of cells (A and B pinealocytes). The cellular hypertrophy and the great development of the pinealocyte organelles in the adult pineal gland makes us think of this gland as a functionally active organ. This functional activity must have remained during the entire period of the time studied (1--5 years), due to the ultrastructural uniformity found and due to the fact that we could not observe any type of degenerative process in the gland. 相似文献
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Brood production rate of Grey Partridges Perdix perdix was studied in three areas in Poland in the years 1986–90, by comparing the number of pairs and the number of family coveys after the breeding period. In the study areas, linear permanent nesting cover was mapped and measured. In these areas the brood production rate declined with increasing spring pair density. A positive effect of the occurrence of nesting cover on brood production rate was found. An increase in the population density mostly occurred through occupying parts of the study area avoided earlier, thus presumably less suitable for Partridges. Pairs occupying these less suitable areas, characterized by less abundant nesting cover, had a lower brood production rate, whereas in the preferred areas this rate did not decline with increasing mean population density. 相似文献
57.
Pilar Puyol M. Dolores Perez José Manuel Ena Miguel Calvo 《Bioscience, biotechnology, and biochemistry》2013,77(10):2515-2520
The interaction of bovine and human whey proteins with retinol and palmitic acid has been studied. Using gel filtration it was found that bovine β-lactoglobulin and α-lactalbumin and serum albumin from both species bind retinol in vitro while the ability to bind palmitic acid is restricted to bovine β-lactoglobulin and bovine and human serum albumin. Using equilibrium dialysis, β-lactoglobulin was found to display two binding sites for retinol per dimeric molecule with an association constant of 1.5 × 104m-1. Competition experiments showed that when the concentration ratio between total fatty acids and retinol is similar to that found in milk, palmitic acid competes with the binding of retinol to β-lactoglobulin. 相似文献
58.
María García-Fernández Panagiotis Karras Agnieszka Checinska Estela Cañón Guadalupe T. Calvo Gonzalo Gómez-López 《Autophagy》2016,12(10):1776-1790
Melanoma is a paradigm of aggressive tumors with a complex and heterogeneous genetic background. Still, melanoma cells frequently retain developmental traits that trace back to lineage specification programs. In particular, lysosome-associated vesicular trafficking is emerging as a melanoma-enriched lineage dependency. However, the contribution of other lysosomal functions such as autophagy to melanoma progression is unclear, particularly in the context of metastasis and resistance to targeted therapy. Here we mined a broad spectrum of cancers for a meta-analysis of mRNA expression, copy number variation and prognostic value of 13 core autophagy genes. This strategy identified heterozygous loss of ATG5 at chromosome band 6q21 as a distinctive feature of advanced melanomas. Importantly, partial ATG5 loss predicted poor overall patient survival in a manner not shared by other autophagy factors and not recapitulated in other tumor types. This prognostic relevance of ATG5 copy number was not evident for other 6q21 neighboring genes. Melanocyte-specific mouse models confirmed that heterozygous (but not homozygous) deletion of Atg5 enhanced melanoma metastasis and compromised the response to targeted therapy (exemplified by dabrafenib, a BRAF inhibitor in clinical use). Collectively, our results support ATG5 as a therapeutically relevant dose-dependent rheostat of melanoma progression. Moreover, these data have important translational implications in drug design, as partial blockade of autophagy genes may worsen (instead of counteracting) the malignant behavior of metastatic melanomas. 相似文献
59.
Dulce?A.?OliveiraEmail author Marco?P.?L.?Parente Bego?a?Calvo Teresa?Mascarenhas Renato?M.?Natal?Jorge 《Biomechanics and modeling in mechanobiology》2016,15(6):1523-1534
Episiotomy is still a controversy issue among physicians, despite the enormous growth of clinical research. Therefore, the potential of numerical modeling of anatomical structures to simulate biomechanical processes was exploited to realize quantitatively the real effects of the episiotomy and its consequences on the pelvic floor muscle. As such, a numerical model was used composed of pelvic floor muscles, a surface delimiting the anterior region, and a fetus body. A normal vaginal delivery without and with different episiotomies was simulated with the fetus in vertex presentation and occipitoanterior position. According to our numerical results, a mediolateral episiotomy has a protective effect, reducing the stress on the muscles, and the force required to delivery successfully up to 52.2 %. The intervention also has benefits on muscle injury, reducing the damage to a small zone. This study demonstrates the feasibility of using a computational modeling approach to study parturition, namely the capability to isolate and evaluate the mechanical significance of a single feature. It must, however, be taken into account that the numerical model does not assess problems that may occur as blood loss, infections and others, so it is necessary to examine whether the benefits of an intervention outweigh the risks. 相似文献
60.