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1.
Monoclonal antibodies in the analysis of fibronectin isoforms generated by alternative splicing of mRNA precursors in normal and transformed human cells 总被引:26,自引:9,他引:17 下载免费PDF全文
L Borsi B Carnemolla P Castellani C Rosellini D Vecchio G Allemanni S E Chang J Taylor-Papadimitriou H Pande L Zardi 《The Journal of cell biology》1987,104(3):595-600
Recent results showing that a single fibronectin gene can give rise to several different mRNAs by alternative splicing have offered an explanation for fibronectin polymorphism. Here we report on monoclonal antibodies that show specificity for a fibronectin segment (ED) that can be included or omitted from the molecule depending on the pattern of splicing of the mRNA precursors. Using these monoclonals, we have quantitatively analyzed the expression of the ED sequence in human fibronectin from different sources. The results demonstrated that, at the protein level, the ED segment is not expressed in plasma fibronectin and that, in fibronectin from the tissue culture medium of tumor-derived or simian virus-40-transformed human cells, the percentage of fibronectin molecules containing the ED segment is about 10 times higher than in fibronectin from normal human fibroblasts. These results suggest that in malignant cells the mechanisms that regulate the splicing of mRNA precursors are altered. 相似文献
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A Bardoni M P Pagliula G Pallavicini S Rindi A A Castellani G De Luca 《The Italian journal of biochemistry》1989,38(5):360-368
UDP-glucose dehydrogenase (UDPGDH) was extracted and partially purified from different rat tissues and the kinetic parameters and some properties of the enzyme were determined and compared. The pH optimum ranged between 8.6 and 9.4 for liver and kidney UDPGDH and between 8.4 and 8.6 for skin and lung UDPGDH. Liver and kidney enzymes showed a similar affinity for both UDPG and NAD. Lung and skin enzymes also showed similar affinity for both substrates, which differed however from that of liver and kidney UDPGDH. Both liver and kidney enzymes had a higher heat stability and a different electrophoretic mobility compared to skin and lung UDPGDH. These data suggest the existence of different tissue specific forms of the enzyme. 相似文献
3.
Structural differences in the cell binding region of human fibronectin molecules isolated from cultured normal and tumor-derived human cells 总被引:2,自引:0,他引:2
Fibronectins isolated from human plasma (pFN) and from the conditioned media of normal (N-cFN) and tumor (T-cFN) human cells were compared by cathepsin D digestion followed by immunostaining of released fragments with the monoclonal antibody 3E3, specific for the cell binding site. Two different staining patterns were obtained, one specific for pFN and N-cFN, the second common to fibronectins from the 3 different kinds of tumors studied. This indicates structural differences between N-cFN and T-cFN in the cell binding region of the fibronectin molecule. 相似文献
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G De Luca M E Tira S Rindi R Salvini G Cetta A A Castellani 《The Italian journal of biochemistry》1984,33(6):403-412
The PGs produced in the growth medium by skin fibroblast cultures from two O.I. affected patients were investigated. After density gradient centrifugation, in the most dense fraction two main families of molecules appeared. The patient with the more severe clinical picture showed a lower content of the PGs with the highest molecular weight. The GAG composition of PGs was different in the two patients. The more severely affected one showed an increase of HS and a decrease of ChS content, in agreement with the lower value of galactosamine to glucosamine ratio in urinary GAGs. 相似文献
5.
Dr. Gastone Giovanni Nussdorfer 《Cell and tissue research》1970,103(3):398-409
Summary The structural changes of the zona juxtamedullaris of the rat adrenal cortex at birth, have been examined by the light and the electron microscope. In this zone clusters of medullary cells lying among the strands of cortical tissue were observed. In the inner portion of the zona juxtamedullaris two types of adrenocortical cells were found: light and very-dark cells. The latter are smaller than the light cells and are always in close connection with the medullary tissue. The ultrastructural features of the very-dark cells suggest that these elements are in degeneration. This finding supports the hypothesis that at birth there is a partial degeneration of the rat zona juxtamedullaris, i.e. the zone corresponding to the fetal zone of some mammalian species.It is proposed that in all mammalian species at birth there is a partial regression of the zona juxtamedullaris and that the regression of the fetal zone is only the quantitative increase of this phenomenon. This hypothesis is discussed in relation to numerous data demonstrating that there are enzymatic conditions in the rat during fetal life, which permit a discrete hypertrophy of the adrenal cortex.The author wishes to express his appreciation to Dr. A. Gambino and to Mr. G. Gottardo for technical assistance. 相似文献
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Castellani John W.; Maresh Carl M.; Armstrong Lawrence E.; Kenefick Robert W.; Riebe Deborah; Echegaray Marcos; Casa Douglas; Castracane V. Daniel 《Journal of applied physiology》1997,82(3):799-806
Castellani, John W., Carl M. Maresh, Lawrence E. Armstrong,Robert W. Kenefick, Deborah Riebe, Marcos Echegaray, Douglas Casa, andV. Daniel Castracane. Intravenous vs. oral rehydration: effects onsubsequent exercise-heat stress. J. Appl.Physiol. 82(3): 799-806, 1997.This studycompared the influence of intravenous vs. oral rehydration afterexercise-induced dehydration during a subsequent 90-min exercisebout. It was hypothesized that cardiovascular, thermoregulatory, and hormonal variables would be the same between intravenous and oral rehydration because of similar restoration ofplasma volume (PV) and osmolality (Osmo). Eight non-heat-acclimated menreceived three experimental treatments (counterbalanced design) immediately after exercise-induced dehydration (33°C) to 4%body weight loss. Treatments were intravenous 0.45% NaCl (iv; 25 ml/kg), no fluid (NF), and oral saline (Oral; 25 ml/kg).After rehydration and rest (2 h total), subjects walked at 50% maximalO2 consumption for up to 90 min at36°C. The following observations were made: 1) heart rate was higher(P < 0.05) in Oral vs. ivat minutes 45, 60, and75 of exercise;2) rectal temperature, sweat rate, percent change in PV, and change in plasma Osmo were similar between ivand Oral; 3) change in plasmanorepinephrine decreased less (P < 0.05) in Oral compared with iv at minute45; 4) changes in plasma adrenocorticotropic hormone and cortisol were similar between ivand Oral after exercise was initiated; and5) exercise time was similar betweeniv (77.4 ± 5.4 min) and Oral (84.2 ± 2.3 min). These datasuggest that after exercise-induced dehydration, iv and Oral wereequally effective as rehydration treatments. Thermoregulation, changein adrenocorticotropic hormone, and change in cortisol were notdifferent between iv and Oral after exercise began; this is likely dueto similar percent change in PV and change in Osmo. 相似文献
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Marcela Xavier Machado Tnia Tarabini Castellani Michele de S Dechoum 《Restoration Ecology》2020,28(5):1273-1282
The restoration of areas invaded by non‐native plants is challenging as invasive plants may affect both biotic and abiotic components of ecosystems, leading to impacts that constrain recolonization by native species after invaders are eliminated. In such a scenario, restoration techniques as topsoil transposition might accelerate colonization by native species in forests. Hedychium coronarium J. Koenig (Zingiberaceae) is a Himalayan herbaceous rhizomatous plant recognized as invasive in several countries. This study aimed to experimentally evaluate the response of plant assemblages to topsoil transposition on a site invaded by H. coronarium after chemical control. Four treatments were applied: chemical control integrated with topsoil transposition, chemical control of H. coronarium alone, topsoil transposition alone, and no intervention (control). Plots were evaluated prior to the application of treatments and then monthly for 11 months after treatments. Parameters were measured for H. coronarium (number of ramets, ramet height, and cover) and other species (species richness, abundance, and cover). Plots treated with chemical control (regardless of topsoil transposition) were similar in terms of all parameters measured and species composition, with dominance of herbs and shrubs. Plots managed solely with topsoil transposition had lower species richness, abundance, and cover, but more diverse life‐forms, being equally rich in climbers, trees, and herbs. Chemical control was effective to control invasion by H. coronarium and increase species richness and abundance on the managed site. Topsoil transposition promoted colonization by species that might accelerate restoration. 相似文献