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ABSTRACT: The present paper shows that human chronic myeloid (K562) cells exposed 3h to 20μM 3′-azido-3′-deoxythymidine (AZT) exhibit
marked variations of the oligosaccharide moiety of glycoconjugates. These changes were analyzed by confocal fluorescence microscopy,
upon incubation of control and AZT-treated cells with biotin–lectin conjugates to visualize cell surface glycans or total
glycans after cells permeabilization. In addition, cell fluorescence distribution of the biotinylated lectins, localized with
streptavidin conjugates labeled with Alexa Fluor 488, was analyzed by flow cytometry. The results obtained show significant
variations on the expression/distribution of membrane surface glycans as detected by both WGA and SNA, two lectins that recognize
primarily cellular internal membrane glycolipids. A further interesting result was the significant increase of N-acetylglucosamine linked glycans localized either at the cell surface or intracellularly but only in K562 cells exposed to
AZT. On the whole, our data demonstrate that AZT alters both lipid and N-linked glycosylations thus confirming previous observations,
from our laboratory and from other Authors, that the drug impair the nucleotide-sugar import in the Golgi’s lumen. AZT does
also alter the O-linked glycosylations that occur in the Golgi complex since these reactions require the incorporation of
sialic acid, GlcNAc and GalNAc all of which are sensitive to the drug.
Molecular and Cellular Biochemistry 04/2012; 300(1):29-37. · 2.06 Impact Factor
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ABSTRACT: Ejaculates from men without known causes for male subfertility and asymptomatic for genital tract inflammation showed infiltration of macrophages, and their activation state (HLA-DR(+)) was negatively correlated with semen parameters and positively correlated with sperm DNA damage. An activation of the immune system is thus detectable in idiopathic oligoasthenoteratozoospermia of unknown origin.
Fertility and sterility 06/2011; 95(8):2676-9.e1-3. · 3.97 Impact Factor
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ABSTRACT: A combination of three selected strains of lactobacilli (Lactobacillus brevis [CD2], L. salivarius [FV2], and L. plantarum [FV9]), whose effectiveness in treating bacterial vaginosis in the form of vaginal tablets has been reported recently, prevented sperm lipid peroxidation that was induced in vitro by a ferrous ion promoter, thus preserving sperm motility and viability. This finding suggests the potential of vaginal probiotic lactobacilli for protecting human spermatozoa from radical oxygen species in the presence of vaginal disorders, thereby improving the fertilization potential of the female host.
Fertility and sterility 04/2011; 95(8):2485-8. · 3.97 Impact Factor
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ABSTRACT: It has recently been reported that the exposure of human spermatozoa to an extremely low frequency (ELF) electromagnetic field (EMF) with a square waveform of 5 mT amplitude and frequency of 50 Hz improves sperm motility. The functional relationship between the energy metabolism and the enhancement of human sperm motility induced by ELF-EMF was investigated. Sperm exposure to ELF-EMF resulted in a progressive and significant increase of mitochondrial membrane potential and levels of ATP, ADP and NAD(+) that was associated with a progressive and significant increase in the sperm kinematic parameters. No significant effects were detected on other parameters such as ATP/ADP ratio and energy charge. When carbamoyl cyanide m-chlorophenylhydrazone (CICCP) was applied to inhibit the oxidative phosphorylation in the mitochondria, the values of energy parameters and motility in the sperm incubated in the presence of glucose and exposed to ELF-EMF did not change, thus indicating that the glycolysis was not involved in mediating ELF-EMF stimulatory effect on motility. By contrast, when pyruvate and lactate were provided instead of glucose, the energy status and motility increased significantly in ELF-EMF-treated sperm. Under these culture conditions, the inhibition of glycolitic metabolism by 2-deoxy-D-glucose (DOG) again resulted in increased values of energy and kinematic parameters, indicating that gluconeogenesis was not involved in producing glucose for use in glycolysis. We concluded that the key role in mediating the stimulatory effects exerted by ELF-EMF on human sperm motility is played by mitochondrial oxidative phosphorylation rather than glycolysis.
Bioelectromagnetics 01/2011; 32(1):15-27. · 1.84 Impact Factor
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[show abstract]
[hide abstract]
ABSTRACT: The present paper shows that human chronic myeloid (K562) cells exposed 3 h to 20 microM 3'-azido-3'-deoxythymidine (AZT) exhibit marked variations of the oligosaccharide moiety of glycoconjugates. These changes were analyzed by confocal fluorescence microscopy, upon incubation of control and AZT-treated cells with biotin-lectin conjugates to visualize cell surface glycans or total glycans after cells permeabilization. In addition, cell fluorescence distribution of the biotinylated lectins, localized with streptavidin conjugates labeled with Alexa Fluor 488, was analyzed by flow cytometry. The results obtained show significant variations on the expression/distribution of membrane surface glycans as detected by both WGA and SNA, two lectins that recognize primarily cellular internal membrane glycolipids. A further interesting result was the significant increase of N-acetylglucosamine linked glycans localized either at the cell surface or intracellularly but only in K562 cells exposed to AZT. On the whole, our data demonstrate that AZT alters both lipid and N-linked glycosylations thus confirming previous observations, from our laboratory and from other Authors, that the drug impair the nucleotide-sugar import in the Golgi's lumen. AZT does also alter the O-linked glycosylations that occur in the Golgi complex since these reactions require the incorporation of sialic acid, GlcNAc and GalNAc all of which are sensitive to the drug.
Molecular and Cellular Biochemistry 07/2007; 300(1-2):29-37. · 2.06 Impact Factor
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[show abstract]
[hide abstract]
ABSTRACT: This work shows that 25 microM quercetin caused a marked inhibition of K562 cells growth together with a mild cytotoxicity, while HSB-2 cells were practically unaffected. Moreover, quercetin induced caspase-3 and cytochrome c-dependent apoptosis almost exclusively in the former cell line. Exposure of K562 cells to quercetin caused also a significant increase of cells in G(2)/M phase that reached the maximum peak at 24 h (4-fold with respect to the basal value). The major sensitivity exhibited by K562 cells was only in part imputable to their higher glutathione content, as compared to HSB-2 cells, thus confirming previous reports describing the formation of intracellular quercetin-thiol toxic adducts in cells exposed to the flavonoid. In fact, after induction of intracellular glutathione increase we detected in both cell lines a significant rise of apoptotic cells, again more marked in K562 cells. By contrast, glutathione-depleted cells, failed to show a decrease of apoptosis in both cell lines, thus contradicting our previous findings and literature data. Since the yet unresolved question about the anti-oxidant or the pro-oxidant capacity of quercetin, we investigated which of these two properties worked in our experimental model. Interestingly, not only quercetin did not produce reactive oxygen species but also prevented their formation, as observed in cells exposed to the oxidizing agent ter-butylhydroperoxide, acting as an efficient oxygen radicals scavenger. This result indicates that quercetin exhibited, in these cell lines, anti-oxidant more than pro-oxidant ability.
Molecular and Cellular Biochemistry 03/2007; 296(1-2):137-49. · 2.06 Impact Factor
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Antonella Tacconelli,
Antonietta R Farina,
Lucia Cappabianca,
Gesilia Cea,
Sonia Panella,
Antonella Chioda,
Rita Gallo, Benedetta Cinque,
Roberta Sferra,
Antonella Vetuschi,
Antonio Francesco Campese,
Isabella Screpanti,
Alberto Gulino,
Andrew R Mackay
[show abstract]
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ABSTRACT: The alternative TrkAIII splice variant is expressed by murine and human thymus. Alternative TrkAIII splicing predominates in postembryonic day E13 (E17 and E18), postnatal murine (3 week and 3 month) and human thymuses, with TrkAIII mRNA expressed by selected thymocyte subsets and thymic epithelial cells (TECs) and a 100 kDa immunoprecipitable TrkAIII-like protein detected in purified thymocyte and whole thymus extracts. FACS and immunohistochemical analysis indicate a non-cell surface localisation for the TrkAIII-like protein in cortical CD4+/CD8+ double positive and, to a lesser extent, single positive thymocyte subsets at the cortex/medulla boundary and in Hassle's corpuscles, reticular epithelial and dendritic cells of the thymic medulla. TrkA(I/II) expression, on the other hand, predominates in sub-capsular regions of the thymus. TrkAIII-like immunoreactivity at the cortex/medulla boundary associates with regions of thymocyte proliferation and not apoptosis. A potential role for thymic hypoxia in thymocyte alternative TrkAIII splicing is supported by reversal to TrkAI splicing by normoxic but not hypoxic culture and induction of Jurkat T cell alternative TrkAIII splicing by the hypoxia mimic CoCl2. In contrast, TEC expression of TrkAIII predominates in both normoxic and hypoxic culture conditions. The data support a potential role for TrkAIII in thymic development and function, of particular relevance to intermediate stage CD4+/CD8+ thymocyte subsets and TECs, which potentially reflects a reversible thymocyte and more permanent TEC adaptation to thymic environment. Since intracellular TrkAIII neither binds nor responds to NGF and can impede regular NGF/TrkA signalling (Tacconelli et al., Cancer Cell, 2004), its expression would be expected to provide an alternative and/or impediment to regular NGF/TrkA signalling within the developing and developed thymus of potential functional importance.
Journal of Neuroimmunology 03/2007; 183(1-2):151-61. · 2.96 Impact Factor
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ABSTRACT: The current study was designed to establish whether extremely low-frequency electromagnetic fields might affect neuronal homeostasis through redox-sensitive mechanisms. To this end, intracellular reactive oxygen species production, antioxidant and glutathione-based detoxifying capability and genomic integrity after extremely low-frequency electromagnetic fields exposure were investigated. Moreover, we also studied potential extremely low-frequency electromagnetic fields-dependent changes in the proliferative and differentiative cellular status. Results seem to support redox-mediated extremely low-frequency electromagnetic fields effects on biological models as, although no major oxidative damage was detected, after exposure we observed a positive modulation of antioxidant enzymatic expression, as well as a significant increase in reduced glutathione level, indicating a shift of cellular environment towards a more reduced state. In addition, extremely low-frequency electromagnetic fields treatment induced a more differentiated phenotype as well as an increased expression in peroxisome proliferators-activated receptor isotype beta, a class of transcription factors related to neuronal differentiation and cellular stress response. As second point, to deepen how extremely low-frequency electromagnetic fields treatment could affect neuroblastoma cell antioxidant capacity, we examined the extremely low-frequency electromagnetic fields-dependent modifications of cell susceptibility to pro-oxidants. Results clearly showed that 50 Hz extremely low-frequency electromagnetic fields exposure reduces cell tolerance towards oxidative attacks.
The International Journal of Biochemistry & Cell Biology 02/2007; 39(11):2093-106. · 4.63 Impact Factor
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ABSTRACT: The activation of phosphoinositide metabolism represents a critical step in the signaling pathways leading to the activation of cytolytic machinery, but its regulation is partially understood. We report here that the stimulation of the low-affinity receptor for immunoglobulin G (IgG) (FcgammaRIIIA, CD16) on primary human natural killer (NK) cells induces a phosphatidylinositol 3-kinase (PI3K)-dependent activation of the small G protein Arf6. We first demonstrate a functional role for Arf6-dependent signals in the activation of the antibody-dependent cellular cytotoxicity (ADCC) attributable to the control of secretion of lytic granule content. We also show that Arf6 couples CD16 to the lipid-modifying enzymes phosphatidylinositol4phosphate 5-kinase type I alpha (PI5KIalpha) and phospholipase D (PLD) that are involved in the control of granule secretion; Arf6, but not Rho family small G proteins RhoA and Rac1, is required for receptor-induced PI5KIalpha membrane targeting as well as for PI5KIalpha and PLD activation. Our findings suggest that Arf6 plays a crucial role in the generation of a phosphatidylinositol4,5-bisphosphate (PIP2) plasma membrane pool required for cytolytic granule-mediated target cell killing.
Blood 08/2005; 106(2):577-83. · 9.90 Impact Factor
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Luisa Di Marzio,
Alfredo Di Leo, Benedetta Cinque,
Donatella Fanini,
Alessio Agnifili,
Pasquale Berloco,
Michele Linsalata,
Dionigi Lorusso,
Michele Barone,
Claudio De Simone,
Maria Grazia Cifone
[show abstract]
[hide abstract]
ABSTRACT: Intestinal alkaline sphingomyelinase, by exerting a major role in dietary sphingomyelin digestion, is responsible for the generation of messengers able to trigger the rapid turnover and apoptosis in intestinal epithelial cells. Markedly reduced mucosal alkaline sphingomyelinase activity has been associated with human colorectal neoplasms. The aim of this study was to analyze the alkaline sphingomyelinase activity in feces from healthy subjects and colorectal adenocarcinoma patients and to correlate it with the enzyme activity in intestinal tissues.
The enzyme activity was measured both in the intestinal samples from 12 healthy controls and 51 patients with colorectal adenocarcinoma (tumoral and paratumoral tissue) and in the fecal samples of 34 healthy subjects and 29 patients with adenocarcinoma. The relation between sphingomyelinase activity and Dukes' stage, cell differentiation degree, age, and gender was also analyzed.
Alkaline sphingomyelinase was significantly decreased (P < 0.001; mean reduction >90%) in tumoral intestinal mucosa of patients compared with controls independently of Dukes' stage and tumor differentiation grade. Interestingly, the enzyme activity in histologically normal paratumoral tissues was statistically lower than control samples (P < 0.001). As occurs in neoplastic tissues, a relevant mean reduction (P < 0.0001; almost 90%) of alkaline sphingomyelinase was revealed in stool samples from tumor patients when compared with controls.
These findings may have implications for cancer biology and perhaps also for the design of clinical test, thus suggesting that the fecal sphingomyelinase activity could really reflect the human intestinal mucosa enzyme level and could represent a new marker for human colorectal adenocarcinoma, mainly taking into account its early appearance in intestinal neoplasms.
Cancer Epidemiology Biomarkers & Prevention 04/2005; 14(4):856-62. · 4.12 Impact Factor
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ABSTRACT: The in vitro effects of resveratrol (RES) on apoptotic pathway in human chronic myeloid (K562) and acute lymphoblastic (HSB-2) leukemia cells were investigated. RES treatment of both cell types significantly and irreversibly inhibited their growth, associated with extensive apoptosis and increase in hypodiploid cells. Cell cycle analysis showed accumulation in G(1) phase in HSB-2 drug exposed cells, while only K562-treated cells exhibited a marked accumulation in S phase with a concomitant decrease in G(1) and G(2)/M at 24 h. Moreover, RES caused internucleosomal DNA fragmentation, even if K562 cells were found less sensitive to the drug, as compared to HSB-2 cells, which also reacted earlier to the treatment. RES-induced apoptosis was associated with an increase of Bax expression and a marked release of cytochrome c from mitochondria. Interestingly, K562 cells exhibited a basal content of glutathione 10-fold that of HSB-2 cells, which increased after 24-48 h RES exposure, together with increment of glutathione reductase and peroxidase activities. However, the major resistance to apoptosis of K562 cells cannot be attributed to their higher pool of reducing power, since neither the inhibition of glutathione synthesis by buthionine sulphoximine nor glutathione depletion by diethylmaleate, sensitized these cells. In addition, glutathione enrichment of HSB-2 cells by N-acetylcysteine did not prevent the apoptotic effects of RES. Our data indicate that RES commitment to apoptosis in both cell lines is independent from the intracellular content of glutathione, while it is associated with either the enhanced expression of Bax and cytochrome c release.
Biochemical Pharmacology 12/2004; 68(10):2019-30. · 4.70 Impact Factor
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ABSTRACT: A reduced amount of total ceramides could be responsible for functional abnormalities of the skin of atopic dermatitis (AD) patients. The ability of an experimental cream containing sonicated Streptococcus thermophilus to increase skin ceramide levels in healthy subjects has been previously reported. The aim of the present work was to investigate the effects of the topical administration of a S. thermophilus-containing cream on ceramide levels of stratum corneum from AD patients. A 2-week application of the cream, containing a sonicated preparation of the lactic acid bacterium S. thermophilus, in the forearm skin of 11 patients led to a significant and relevant increase of skin ceramide amounts, which could have resulted from the sphingomyelin hydrolysis through the bacterial sphingomyelinase. Moreover, in all patients the topical application of our experimental cream also resulted in the improvement of the signs and symptoms characteristic of AD skin (i.e. erythema, scaling, pruritus).
Experimental Dermatology 11/2003; 12(5):615-20. · 3.54 Impact Factor
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ABSTRACT: The importance of sphingolipids, not only as components of plasma membranes but also as key players in different physiological and pathophysiological cellular events, is now emerging. This review gathers together what the authors feel are the most relevant data, present in the literature, regarding the roles and the effects of sphingolipids, such as ceramide, ceramide-1-phosphate (C1P), sphingosine (SP) and sphingosine-1-phosphate (S1P), on the development, activation and regulation of the immune system.
Pharmacological Research 06/2003; 47(5):421-37. · 4.44 Impact Factor
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ABSTRACT: CD69 C-type lectin receptor represents a functional triggering molecule on activated NK cells, capable of directing their natural killing function. The receptor-proximal signaling pathways activated by CD69 cross-linking and involved in CD69-mediated cytotoxic activity are still poorly understood. Here we show that CD69 engagement leads to the rapid and selective activation of the tyrosine kinase Syk, but not of the closely related member of the same family, ZAP70, in IL-2-activated human NK cells. Our results indicate the requirement for Src family kinases in the CD69-triggered activation of Syk and suggest a role for Lck in this event. We also demonstrate that Syk and Src family tyrosine kinases control the CD69-triggered tyrosine phosphorylation and activation of phospholipase Cgamma2 and the Rho family-specific exchange factor Vav1 and are responsible for CD69-triggered cytotoxicity of activated NK cells. The same CD69-activated signaling pathways are also observed in an RBL transfectant clone, constitutively expressing the receptor. These data demonstrate for the first time that the CD69 receptor functionally couples to the activation of Src family tyrosine kinases, which, by inducing Syk activation, initiate downstream signaling pathways and regulate CD69-triggered functions on human NK cells.
The Journal of Immunology 08/2002; 169(1):68-74. · 5.79 Impact Factor
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ABSTRACT: In this study we analyzed the signaling pathway triggered by GM3 in lymphoblastoid T-cells. In these cells, GM3 induced cPLA2 activation, arachidonic acid release, and PKC-delta translocation. In order to clarify the upstream molecular signals triggered by GM3, we analyzed the activation of extracellular signal-regulated kinase (ERK)s, a downstream effector of Ras-regulated cytoplasmic kinase cascade. Our results showed that GM3 treatment led to rapid ERK phosphorylation in lymphoblastoid T-cells, as detected by anti-phospho-p44/42 MAP kinase. Similar findings were found in human peripheral blood lymphocytes. Moreover, we showed that GM3 specifically phosphorylated ERK-2, as revealed by anti-phosphotyrosine reactivity on both cell free lysates and ERKs immunoprecipitates. The role of the CD4 cytoplasmic domain in GM3-triggered signaling pathway was investigated using A2.01/CD4-cyt399 cells, which had been transfected with a mutant form of CD4 lacking the bulk of the cytoplasmic domain. In these cells GM3 induced cPLA2 activation, arachidonic acid release, and PKC-delta translocation, but not CD4 endocytosis, indicating that the CD4 cytoplasmic domain plays a key role in GM3-triggered CD4 endocytosis and the GM3-triggered biochemical pathway is upstream of CD4 phosphorylation. These findings strongly suggest that GM3 triggers a novel signaling pathway involved in the regulation of cellular functions.
The Journal of Lipid Research 07/2002; 43(6):971-8. · 5.56 Impact Factor
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[show abstract]
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ABSTRACT: In this report the molecular mechanism(s) involved in the rapid and selective endocytosis of cell surface glycoprotein CD4
induced by exogenous monosialoganglioside GM3 in human peripheral blood lymphocytes have been investigated. Inhibition of
the GM3-induced CD4 down-modulation was observed in the presence of specific protein kinase C (PKC) inhibitors. Scanning confocal
microscopy revealed the translocation and clustering on the cell surface of PKC isozymes δ and θ (more evidently than α and
β) after GM3 treatment, suggesting the involvement of these isozymes in the ganglioside-induced CD4 down-modulation. Exogenous
GM3 induced phosphorylation of CD4 molecule, which then dissociated from p56lck, as early as after 5 min. Moreover, addition of GM3 resulted in a rapid (1 min) cytosolic phospholipase A2 activation with consequent arachidonic acid release, whereas no phosphatidylinositol-phospholipase C activity was observed.
Both PKC translocation and CD4 down-modulation were blocked by the trifluoromethylketone analog of arachidonic acid, a selective
inhibitor of cytosolic phospholipase A2 and by mitogen-activated protein kinase inhibitor PD98059. Taken together, these findings strongly suggest that GM3 may trigger
a novel mechanism of modulation of the CD4 surface expression through the activation of enzyme(s) involved in the regulation
of cellular functions.
Journal of Biological Chemistry 12/1998; 273(52):35153-35160. · 4.77 Impact Factor
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[show abstract]
[hide abstract]
ABSTRACT: The current study was designed to establish whether extremely low-frequency electromagnetic fields might affect neuronal homeostasis through redox-sensitive mechanisms. To this end, intracellular reactive oxygen species production, antioxidant and glutathione-based detoxifying capability and genomic integrity after extremely low-frequency electromagnetic fields exposure were investigated. Moreover, we also studied potential extremely low-frequency electromagnetic fields-dependent changes in the proliferative and differentiative cellular status. Results seem to support redox-mediated extremely low-frequency electromagnetic fields effects on biological models as, although no major oxidative damage was detected, after exposure we observed a positive modulation of antioxidant enzymatic expression, as well as a significant increase in reduced glutathione level, indicating a shift of cellular environment towards a more reduced state. In addition, extremely low-frequency electromagnetic fields treatment induced a more differentiated phenotype as well as an increased expression in peroxisome proliferators-activated receptor isotype β, a class of transcription factors related to neuronal differentiation and cellular stress response. As second point, to deepen how extremely low-frequency electromagnetic fields treatment could affect neuroblastoma cell antioxidant capacity, we examined the extremely low-frequency electromagnetic fields-dependent modifications of cell susceptibility to pro-oxidants. Results clearly showed that 50 Hz extremely low-frequency electromagnetic fields exposure reduces cell tolerance towards oxidative attacks.
The International Journal of Biochemistry & Cell Biology.
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[hide abstract]
ABSTRACT: The aim of this work was to evaluate the effect of stratospheric radiations on neural tumour cells. ADF human glioblastoma cells were hosted on a stratospheric balloon within the 2002 biological experiment campaign of the Italian Space Agency. The flight at an average height of 37 km lasted about 24 hrs. Cell morphology, number and viability, cell cycle and apoptosis, some antioxidant enzymes and proteins involved in cell cycle regulation, DNA repair and gene expression were studied. Stratospheric radiations caused a significant decrease in cell number, as well as a block of proliferation, but not apoptosis or necrosis. Radiations also induced activation and induction of some antioxidant enzymes, increase in DNA repair-related proteins (p53 and Proliferating Cell Nuclear Antigen) and variations of the transcription factors Peroxisome Proliferator-Activated Receptors. Morphologically, test cells exhibited more electron dense cytoplasm and less condensed chromatin than controls and modification of their surfaces. Our results indicate that glioblastoma cells, exposed to continuous stratospheric radiations for 24 hrs, show activation of cell cycle check point, decrease of cell number, variations of Peroxisome Proliferator-Activated Receptors and increase of Reactive Oxygen Species-scavenging enzymes.
The Italian journal of biochemistry 54(3-4):276-86.
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ABSTRACT: To find out if the combination for intravitreal use of the antibody bevacizumab (AvastinTM; Genentech, Inc., San Francisco, CA) and triamcinolone acetonide (TA) (Kenacort; Bristol-Myers Squibb, Anagni, Italy) could affect over time the anti -vascular endothelial growth factor (VEGF) activity of bevacizumab.
Two different combined preparations were obtained, drawing up together 1.25 mg/0.05 mL of bevacizumab and 2 mg/0.05 mL (B+TA(2mg)) or 4 mg/0.05 mL (B+TA(4mg)) of TA into insulin syringes with 29-G needle. Control preparations were obtained with bevacizumab and an injectable solution (B). The syringes were stored refrigerated at 4 degrees C. The bevacizumab concentration was measured, through its binding to VEGF-165 isoform, at 48 hours and at 1 week.
No preparations showed statistically significant changes in bevacizumab concentration with time (p=0.74 for B+T(2mg), p=0.92 for B+T(4mg), p=0.57 for B). The B+TA(2mg) preparations showed a larger percentage of degradation of bevacizumab than the B+TA(4mg) preparations (28.4% versus 17.6% at 48 hours; 26.4% versus 18% at 1 week). The B control preparations showed the lowest drug degradation: 9.6% at 48 hours and 14.8% at 1 week.
After storage at 4 degrees C for 48 hours and 1 week, the combined preparations showed a larger reduction in bevacizumab concentration than the control preparations. No significant change was observed with the length of storage. The preparations obtained mixing 4 mg/0.05 mL of TA and 1.25 mg/0.05 mL of bevacizumab maintained the highest anti-VEGF activity over time.
European journal of ophthalmology 19(5):842-7. · 0.96 Impact Factor
