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961.
962.
963.
Alves Diego Corrêa Vasconcelos Lilian Paula da Câmara Luís Fernando Hahn Lisiane Agostinho Angelo Antonio 《Reviews in Fish Biology and Fisheries》2019,29(2):501-512
Reviews in Fish Biology and Fisheries - Migratory fishes are one of the groups most threatened by the interruption of river connectivity caused by reservoirs and dams. The downstream displacement... 相似文献
964.
Cristina Panuzzo Sabrina Crivellaro Giovanna Carrà Angelo Guerrasio Giuseppe Saglio Alessandro Morotti 《PloS one》2014,9(10)
Chronic myeloid leukemia (CML) is a myeloproliferative disorder characterized by the t(9;22) translocation coding for the chimeric protein p210 BCR-ABL. The tumor suppressor PTEN plays a critical role in the pathogenesis of CML chronic phase, through non genomic loss of function mechanisms, such as protein down-regulation and impaired nuclear/cytoplasmic shuttling. Here we demonstrate that BCR-ABL promotes PTEN downregulation through a MEK dependent pathway. Furthermore, we describe a novel not recurrent N212D-PTEN point mutation found in the EM2 blast crisis cell line. 相似文献
965.
Paola Di Natale Carmela Di Domenico Guglielmo R D Villani Angelo Lombardo Antonia Follenzi Luigi Naldini 《European journal of biochemistry》2002,269(11):2764-2771
Mucopolysaccharidosis type I (MPS I) results from a deficiency in the enzyme alpha-L-iduronidase (IDUA), and is characterized by skeletal abnormalities, hepatosplenomegaly and neurological dysfunction. In this study, we used a late generation lentiviral vector to evaluate the utility of this vector system for the transfer and expression of the human IDUA cDNA in MPS I fibroblasts. We observed that the level of enzyme expression in transduced cells was 1.5-fold the level found in normal cells; the expression persisted for at least two months. In addition, transduced MPS I fibroblasts were capable of clearing intracellular radiolabeled glycosaminoglycan (GAG). Pulse-chase experiments on transduced fibroblasts showed that the recombinant enzyme was synthesized as a 76-kDa precursor form and processed to a 66-kDa mature form; it was released from transduced cells and was endocytosed into a second population of untreated MPS I fibroblasts via a mannose 6-phosphate receptor. These results suggest that the lentiviral vector may be used for the delivery and expression of the IDUA gene to cells in vivo for treatment of MPS I. 相似文献
966.
Angelo G. Gambarini Catarina A. Miyamoto Geovani A. Lima Helena B. Nader Carl P. Dietrich 《Molecular and cellular biochemistry》1993,124(2):121-129
The mitogenic activity of acidic fibroblast growth factor (aFGF) is potentiated by the highly sulfated hexasaccharide [IdoUA,2S-GlcNS,6S]2-[GlcUA-GlcNS,6S] the structural repetitive unit of lung heparin chains. On a mass basis, the effect of both heparin and oligosaccharide are equivalent whereas on a molar basis, heparin, which contains about seven hexasaccharide repeats, is more efficient. On the other hand, a pentasulfated tetrasaccharide or di- and trisulfated disaccharides are much less effective in potentiating aFGF activity than the hexasaccharide. If the growth factor is pre-incubated with the hexasaccharide at pH 7.2 and then exposed to pH 3.5 the 306/345 nm fluoresence ratio is similar to that of native aFGF indicating that the oligosaccharide stabilizes a native conformation of the protein. Heparan sulfates extracted from various mammalian tissues were also able to potentiate aFGF mitogenic activity. On a mass basis they were in general less efficient than heparin; however, heparan sulfate prepared from medium conditioned by 3T3 fibroblasts is more efficient than heparin both on a mass and molar basis. A highly sulfated oligosaccharide isolated after digestion of pancreas heparan sulfate with heparitinase I is more active than the intact molecule, reaching a potentiating effect equivalent to that of lung heparin, whereas an N-acetylated oligosaccharide isolated after nitrous acid degradation is inactive. These data suggest that the mitogenic activity of aFGF is primarily potentiated by interacting with highly sulfated regions of heparan sulfates chains.Abbreviations aFGF,bFGF
acidic and basic fibroblast growth factor
- DMEM
Dulbecco's modified Eagle's medium
- FCS
fetal calf serum
- U,2S-(14)-GlcNS,6S
O--L-ido(ene-pyranosyluronic acid 2-O-sulfate)-(14)-2-sulfoamino-2-deoxy-D-glucose-6-O-sulfate
- U-(14)-GlcNS,6S
O-(ene-pyranosyluronic acid)-(14)-2-sulfoamino-2-deoxy-D-glucose-6-O-sulfate
- IdoUA
iduronic acid
- GlcUA
glucuronic acid
- GlyUA
uronic acid; GlcNAcN-acetylglycosamine
- GlcNS
N-sulfated glucosamine
- GlcNS,6S
N,6-disulfated glucosamine
- Gal
galactose
- Xyl
xylose
- Ser
serine
- HS
heparan Sulfate 相似文献
967.
Antonio Migheli Angelo Attanasio Maria Teresa Giordana 《Biotechnic & histochemistry》1993,68(2):117-121
A postembedding staining method is presented for ultrastructural visualization of amyloid deposits in brain sections from patients with Alzheimer's disease. Methenamine silver stain is applied to thin sections of tissue embedded in the acrylic resin LR Gold. Senile plaques are easily labeled by silver granules and the ultrastructural detail is well preserved. When staining time is prolonged, silver precipitate also is deposited on neuronal paired helical filaments. This method overcomes the drawbacks of previously reported applications of the stain on Vibra-tome and Epon sections. Thin sections from the same tissue block can be immunostained with antibodies to various plaque components, thus allowing comparative studies at the electron microscope level. 相似文献
968.
Béatrice Mathiot Angelo Perani Dominique Dumas Michel Maugras Jacques Didelon Jean-François Stoltz 《Cytotechnology》1993,11(1):41-48
Hybridoma cell growth and monoclonal antibody production were investigated with a laboratory-made system in which cells were grown in dialysis tubing (MW cut-off 25 kD). The dialysis system contained 10 ml of cell suspension and was immersed in 200 ml of culture medium which when replaced or was at 4-day intervals. With this system, monoclonal antibody concentrations similar to those observed in ascites (concentrations in the order of one gramme per liter) were obtained. With no medium replacement, the antibody production was 3.3 g/l and the cell productivity 3.2×10–8 g of IgM produced per cell in one minute. With medium replacement the antibody production was higher, 4.4 g/l but the cell productivity was lower, 1.49×10–8 g per cell in one minute. Cells cultivated in non-optimized conditions were better producers than cells growing in a good environment.Abbreviations FCS
fetal calf serum
- Ig
immunoglobulin
- MAb
monoclonal antibody
- MW
molecular weight
- MWCO
molecular weight cut off
- RM
replaced medium
- NRM
non replaced medium 相似文献
969.
Summary The chromosome complement and some karyological features were investigated in the pelagic amphipod Hyperiella dilatata Stebbing 1888 from the Ross Sea (Antarctica). The diploid karyotype consists of 48 metacentric and 10 submetacentric elements (2n = 58). The presence of secondary constrictions and supernumerary chromosomes is described. Available chromosome numbers of Hyperiidea exhibit a wide range of distribution, among which Hyperiella dilatata is the closest to the modal number of other amphipods. 相似文献
970.
Annarosa Arcangel Laura Faravelli Laura Bianchi Barbara Rosati Angela Gritti Angelo Vescovy Enzo Wanke Massimo Olivotto 《Cell communication & adhesion》1996,4(4):369-385
Changes in the resting potential (Vrest) and in the underlying ionic conductances were measured by the patch-clamp technique in SH-SY5Y human neuroblastoma cells exposed to substrate-bound or soluble Laminin (bLN: sLN), as compared to integrin-independent substrates (polylysine (PL); bovine serum albumin (BSA)). While PL and BSA were ineffective, both forms of LN caused an early (5-15 min) activation of a peculiar type of Inwardly Rectifying K- current (I,ir) characterised by a voltage-dependent inactivation in the range of membrane potentials around —50/0 mV. Iir was blocked by Cs+ ions and by the antiarrhythmic drug E-4031, a specific inhibitor of the HERG-codified channels. In cells adherent to bLN, I,ir potentiation (85%) persisted for 90-120 min and was accompanied by a similar, but transient, increase in the leakage conductance (Gl). Successively, the persistence of a high Iir conductance and the decrease of Gl progressively bring Vrest from -12 to -30 mV in about 120 min. On the other hand, in cells adherent to PL, exposure to sLN produced a similar but not persistent activation of Iir, without any increase in Gl: this caused a rapid, transient hyperpolarisation of Vrest The effects of bLN and sLN were mimicked by antibodies raised against the integrin β1 subunit, suggesting a specific integrin-mediated mechanism. In fact, when bound to the culture dishes, these antibodies simultaneously activated the Iir and Gl, whereas in soluble form they only activated Iir. Cells adherent to bLN emitted neurites, a process impaired by the block of Iir by E-4031 and Cs+. On the whole data suggest that the integrin-mediated activation of Iir plays a crucial role in the commitment to neuritogenesis of neuroblastoma cells, independently on the effects of this activation on Vrest. 相似文献