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61.
M. Giovanna Parisi Matteo Cammarata Gigliola Benenati Giuseppina Salerno Valentina Mangano Aiti Vizzini Nicolò Parrinello 《Cell and tissue research》2010,341(2):279-288
The purification, cloning, sequencing, molecular properties and expression of a fucose-binding lectin from the serum of Dicentrarchus labrax (DlFBL) have been previously reported. We now describe the distribution and expression of DlFBL during fish ontogeny. Immunohistochemistry
and in situ hybridization assays were carried out at various developmental stages (from 10 days post-hatching larvae to juveniles).
Another fucose-binding lectin, similar to DlFBL in biochemical, immunochemical and agglutinating properties, was extracted
and purified from eggs and appeared to be localized in the embryo yolk sack residual. DlFBL was found in columnar and goblet
cells of the intestinal epithelium of larvae (from 20 days post-hatching) and juveniles and in parenchymal tissue of juveniles.
DlFBL mRNA and protein were detected in the intestinal epithelium and in hepatocytes. An amplification product from degenerate
primers indicates that lectin isotypes with DlFBL epitopes are expressed in eggs and embryos. Whether the lectin fraction
isolated from eggs and embryos includes DlFBL of maternal origin remains unclear. 相似文献
62.
Andrea Franzetti Isabella Gandolfi Marco Piscitello Giovanni Porto Adriano Biasiolo Francesca Oltolini Tomaso Marangoni Giuseppina Bestetti 《Biodegradation》2010,21(2):193-201
The effectiveness of biosparging to mitigate N,N diethylaniline in aquifer was evaluated by measuring the time course of decrease in concentration of the aforementioned compound
in aerobic microcosm experiments. The first-order kinetic constant for N,N diethylaniline aerobic biodegradation was estimated from microcosm data (0.037 ± 0.004 d−1), and the value was consistent with the best-fitting value in the transport and reaction model of the aquifer (0.020 d−1). Furthermore, the biodegradability of the compound was evaluated under anaerobic condition in microcosm experiments, which
was supported by field modelling. There was no significant degradation in the anaerobic microcosm experiments, confirming
the recalcitrance of N,N diethyl aniline under the aforementioned aquifer condition. 相似文献
63.
Federica Della Rovere Chiara A Airoldi Giuseppina Falasca Alessandra Ghiani Laura Fattorini Sandra Citterio Martin Kater Maria Maddalena Altamura 《Plant signaling & behavior》2010,5(6):677-680
Proteins containing bromodomains are capable of binding to acetylated histone tails and have a role in recognizing and deciphering acetylated chromatin. Plant BET proteins contain one bromodomain. Twelve BET-encoding genes have been identified in the Arabidopsis genome. Two of these genes have been functionally characterized, one shows a role in seed germination, the other is involved in the establishment of leaf shape. Recently, we characterized a third AtBET gene, named GTE4. We demonstrated that GTE4 is involved in the activation and maintenance of cell division in the meristems and by this controls cell numbers in differentiated organs. Moreover, the quiescent center (QC) identity is partially lost in the apex of the primary root of gte4 mutant, and there is a premature switch from mitosis to endocycling. Genes involved in the retinoblastoma (RB)-E2F pathway, which is important for coupling cell division and cell differentiation in plants and animals, were either up or downregulated in the gte4 mutant. In this report we also show that the defect in germination observed in gte4 mutant seeds is not rescued by the action of GA3. Further the root pole of the mutant embryo shows irregular cytokinesis in the procambial stem cells, and the QC of the lateral root shows a partial, but not transient, loss of QC identity. These additional results reinforce the importance of GTE4 in the control of cell proliferation.Key words: arabidopsis, BET bromodomain, cell cycle, E2F, germination 相似文献
64.
Carbonic anhydrase IX: Biochemical and crystallographic characterization of a novel antitumor target
Giuseppina De Simone Claudiu T. Supuran 《Biochimica et Biophysica Acta - Proteins and Proteomics》2010,1804(2):404-409
Isoform IX of the zinc enzyme carbonic anhydrase (CA, EC 4.2.1.1), CA IX, is a transmembrane protein involved in solid tumor acidification through the HIF-1α activation cascade. CA IX has a very high catalytic activity for the hydration of carbon dioxide to bicarbonate and protons, even at acidic pH values (of around 6.5), typical of solid, hypoxic tumors, which are largely unresponsive to classical chemo- and radiotherapy. Thus, CA IX is used as a marker of tumor hypoxia and as a prognostic factor for many human cancers. CA IX is involved in tumorigenesis through many pathways, such as pH regulation and cell adhesion control. The X-ray structure of the catalytic domain of CA IX has been recently reported, being shown that CA IX has a typical α-CA fold. However, the CA IX structure differs significantly from the other CA isozymes when the protein quaternary structure is considered. Thus, two catalytic domains of CA IX associate to form a dimer, which is stabilized by the formation of an intermolecular disulfide bond. The active site clefts and the proteoglycan (PG) domains are located on one face of the dimer, while the C-termini are located on the opposite face to facilitate protein anchoring to the cell membrane. As all mammalian CAs, CA IX is inhibited by several main classes of inhibitors, such as the inorganic anions, the sulfonamides and their bioisosteres (sulfamates, sulfamides, etc.), the phenols, and the coumarins. The mechanism of inhibition with all these classes of compounds is understood at the molecular level, but the sulfonamides and their congeners have important applications. It has been recently shown that both in vitro, in cell cultures, as well as in animals with transplanted tumors, CA IX inhibition with sulfonamides lead to a return of the extracellular pH to more normal values, which leads to a delay in tumor growth. As a consequence, CA IX represents a promising antitumor target for the development of anticancer agents with an alternative mechanism of action. 相似文献
65.
66.
Giuseppina Sandri Maria Cristina Bonferoni Silvia Rossi Franca Ferrari Cinzia Boselli Carla Caramella 《AAPS PharmSciTech》2010,11(1):362-371
The aim of this paper was to evaluate the penetration enhancement properties of nanoparticles (NP) based on N-trimethyl chitosan (TMC 35% quaternization degree) loaded with insulin. The permeation performances of TMC NP were compared
with those of chitosan (CS) NP and also with TMC and CS solutions. To estimate the mechanism of penetration enhancement, two
different approaches have been taken into account: an in vitro study (Caco-2 cells) and an ex vivo study (excised rat duodenum, jejunum, and ileum). Insulin-loaded CS and TMC NP had dimensions of about 250 nm and had high
yield and high encapsulation efficiency. The in vitro study evidenced that TMC and CS were able to enhance insulin permeation to the same extent. Penetration enhancement properties
of TMC NP seem to be prevalently related to endocytosis while the widening of tight junctions appeared more important as mechanism
in the case of CS NP. The ex vivo study put in evidence the role of mucus layer and of its microclimate pH. In duodenum (pH 5–5.5), CS and TMC solutions were
more effective than NP while TMC NP were more efficient towards jejunum tissue (pH 6–6.5) for their high mucoadhesive potential.
Confocal laser scanning microscopy study supported the hypothesis that penetration enhancement due to TMC NP was mainly due
to internalization/endocytosis into duodenum and jejunum epithelial cells. The good penetration enhancement properties (permeation
and penetration/internalization) make TMC NP suitable carriers for oral administration of insulin. 相似文献
67.
68.
Role of c-Abl in directing metabolic versus mitogenic effects in insulin receptor signaling 总被引:3,自引:0,他引:3
Frasca F Pandini G Malaguarnera R Mandarino A Messina RL Sciacca L Belfiore A Vigneri R 《The Journal of biological chemistry》2007,282(36):26077-26088
c-Abl is a cytoplasmic tyrosine kinase involved in several signal transduction pathways. Here we report that c-Abl is involved also in insulin receptor signaling. Indeed, c-Abl tyrosine kinase is activated upon insulin stimulation. Inhibition of c-Abl tyrosine kinase by STI571 attenuates the effect of insulin on Akt/GSK-3beta phosphorylation and glycogen synthesis, and at the same time, it enhances the effect of insulin on ERK activation, cell proliferation, and migration. This effect of STI571 is specific to c-Abl inhibition, because it does not occur in Abl-null cells and is restored in c-Abl-reconstituted cells. Numerous evidences suggest that focal adhesion kinase (FAK) is involved in mediating this c-Abl effect. First, anti-phosphotyrosine blots indicate that c-Abl tyrosine kinase activation is concomitant with FAK dephosphorylation in response to insulin, whereas c-Abl inhibition is accompanied by FAK phosphorylation in response to insulin, a response similar to that observed with IGF-I. Second, the c-Abl effects on insulin signaling are not observed in cells devoid of FAK (FAK(-/-) cells). Taken together these results suggest that c-Abl activation by insulin, via a modification of FAK response, may play an important role in directing mitogenic versus metabolic insulin receptor signaling. 相似文献
69.
First reported patient with human ERCC1 deficiency has cerebro-oculo-facio-skeletal syndrome with a mild defect in nucleotide excision repair and severe developmental failure
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Jaspers NG Raams A Silengo MC Wijgers N Niedernhofer LJ Robinson AR Giglia-Mari G Hoogstraten D Kleijer WJ Hoeijmakers JH Vermeulen W 《American journal of human genetics》2007,80(3):457-466
Nucleotide excision repair (NER) is a genome caretaker mechanism responsible for removing helix-distorting DNA lesions, most notably ultraviolet photodimers. Inherited defects in NER result in profound photosensitivity and the cancer-prone syndrome xeroderma pigmentosum (XP) or two progeroid syndromes: Cockayne and trichothiodystrophy syndromes. The heterodimer ERCC1-XPF is one of two endonucleases required for NER. Mutations in XPF are associated with mild XP and rarely with progeria. Mutations in ERCC1 have not been reported. Here, we describe the first case of human inherited ERCC1 deficiency. Patient cells showed moderate hypersensitivity to ultraviolet rays and mitomycin C, yet the clinical features were very severe and, unexpectedly, were compatible with a diagnosis of cerebro-oculo-facio-skeletal syndrome. This discovery represents a novel complementation group of patients with defective NER. Further, the clinical severity, coupled with a relatively mild repair defect, suggests novel functions for ERCC1. 相似文献
70.
Scala S Ieranò C Ottaiano A Franco R La Mura A Liguori G Mascolo M Staibano S Ascierto PA Botti G De Rosa G Castello G 《Cancer immunology, immunotherapy : CII》2007,56(10):1589-1595
PURPOSE: Although relatively rare, uveal melanoma is the most common ocular tumor of adults. Up to half of uveal melanoma patients die of metastatic disease. CXCR4, a chemokine receptor, is a prognostic factor in cutaneous melanoma involved in angiogenesis and metastasis formation. The aim of this study was to evaluate the expression of CXCR4 in uveal melanoma. METHODS: CXCR4 was detected by immunohistochemistry in 44 samples of uveal melanoma. Staining was categorized into three semiquantitative classes based on the rate of stained (positive) tumor cells: absence of staining, <50% of cell (+) and >50% (++). Correlations between CXCR4 expression, data on patient and tumor features were studied by contingency tables and the chi2 test. Time-to-event curves were studied using the Kaplan-Meier method. Univariate analysis was performed using the log-rank test. Ninety-five percent confidence intervals (95% CI) of hazard ratios were also reported. RESULTS: Staining for CXCR4 protein was absent in 18 tumors (40.9%), present in <50% of cells in 19 (43.2%) and in >50% of cells in 7 (15.9%) tumors. CXCR4 expression correlated to the epithelioid-mixed cell type (P=0.030). No statistically significant relation emerged between CXCR4 expression, largest tumor diameter (LTD) and extracellular matrix patterns as evaluated through histological patterns stained with periodic acid-Schiff (PAS). Events occurred in 2 out of 18 patients (11.1%) with negative tumors (2 deaths), in 3 out of 19 patients (15.8%) with <50% of positive tumor cells (2 deaths and 1 occurrence of metastases) and in 1 out of 7 patients (14.3%) with >50% of positive tumor cells (1 occurrence of metastases). The cell type (P=0.0457) but not CXCR4 showed prognostic value at univariate analysis. CONCLUSION: This study shows that CXCR4 is commonly expressed in uveal melanoma and correlates with cell type a well-established prognostic factor. 相似文献