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Merli M, Salerno F, Riggio O, de Franchis R, Fiaccadori F, Meddi P, Primignani M, Pedretti G, Maggi A, Capocaccia L, Lovaria A, Ugolotti U, Salvatori F, Bezzi M, Rossi P. Transjugular intrahepatic portosystemic shunt versus endoscopic sclerotherapy for the prevention of variceal bleeding in cirrhosis: a randomized multicenter trial. Gruppo Italiano Studio TIPS (G.I.S.T.). Hepatology 1998; 27:48-53. [PMID: 9425916 DOI: 10.1002/hep.510270109] [Citation(s) in RCA: 120] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Transjugular intrahepatic portosystemic shunt (TIPS), a new technique for the treatment of portal hypertension, has been successful in preliminary studies to treat acute variceal hemorrhage and to prevent variceal rebleeding. The purpose of this multicenter, randomized controlled trial is to compare the efficacy of TIPS with that of endoscopic sclerotherapy in the prevention of variceal rebleeding in cirrhosis. Eighty-one cirrhotic patients, with endoscopically proven variceal bleeding, were randomized to either TIPS (38 patients) or endoscopic sclerotherapy (43 patients). Randomization was stratified according to the following: if bleeding occurred < 1 week (stratum I); if bleeding occurred 1 to 6 weeks (stratum II); and if bleeding occurred 6 weeks to 6 months (stratum III) before enrollment. Follow-up included clinical, biochemical, Doppler Ultrasound, and endoscopic examinations every 6 months. During a mean follow-up of 17.7 months, 51% of the patients treated with sclerotherapy and 24% of those treated with TIPS rebled (P = .011). Mortality was 19% in sclerotherapy patients and 24% in TIPS patients (P = .50). Hepatic encephalopathy (HE) developed in 26% and 55%, respectively (P = .006). A separate analysis of the three strata showed that TIPS was significantly more effective than sclerotherapy (P = .026) in preventing rebleeding only in stratum I patients. TIPS is significantly better than sclerotherapy in preventing rebleeding only when it is performed shortly after a variceal bleed; however, TIPS does not improve survival and is associated with a significantly higher incidence of HE. The overall performance of TIPS does not seem to justify the adoption of this technique as a first-choice treatment to prevent rebleeding from esophageal varices in cirrhotic patients.
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Agrati P, Garnier M, Patrone C, Pollio G, Santagati S, Vegeto E, Maggi A. SK-ER3 neuroblastoma cells as a model for the study of estrogen influence on neural cells. Brain Res Bull 1997; 44:519-23. [PMID: 9370219 DOI: 10.1016/s0361-9230(97)00237-2] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The neuroblastoma SK-ER3 cell line obtained by stable transfection of the human SK-N-BE cell line is proposed as a model for the study of estrogen receptor activity in cells of neural origin. In the SK-ER3 cell line the estrogen receptor, once activated, initiates a differentiation program leading to growth arrest, morphological changes, and acquisition of the dopaminergic phenotype. In the absence of estrogens, this program can be triggered by IGF-I, which can activate the unliganded estrogen receptor via the ras-pathway. It is proposed that this model system might recapitulate the events occurring in vivo during the differentiation of the nervous system and that IGF-I may play an important role in the activation of estrogen receptor at the very early stage of brain development affecting the differentiation of a number of hypothalamic and extrahypothalamic brain regions.
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Santagati S, Garnier M, Carlo P, Violani E, Picotti GB, Maggi A. Quantitation of low abundance mRNAs in glial cells using different polymerase chain reaction (PCR)-based methods. BRAIN RESEARCH. BRAIN RESEARCH PROTOCOLS 1997; 1:217-23. [PMID: 9385056 DOI: 10.1016/s1385-299x(96)00033-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The conventional methods for mRNA quantitation such as Northern blotting or ribonuclease protection assay sometimes lack enough sensitivity to study low abundance mRNAs or to work with limited amounts of biological samples. The sensitivity of the polymerase chain reaction (PCR) linked to reverse transcription (RT-PCR) has proven useful in amplifying specific mRNAs, especially those present in low copy number. Though, the quantitation of nucleic acids by means of PCR has proven problematic. The main constraint in obtaining quantitative data is inherent in the amplification reaction. Because amplification is an exponential process, small variations in the efficiency of amplification may significantly affect the final yield of the PCR product. The variables that influence the rate of the PCR include the abundance of the mRNA present in the starting material, the concentrations of the Taq DNA polymerase, dNTPs and magnesium ions, the annealing and elongation conditions, the ramping temperatures and the formation of primer secondary structures. Moreover, with the progression of the PCR cycles, reagents are consumed and inhibitors generated, leading to non-linear synthesis of DNA. Finally, tube-to-tube variations sometimes preclude accurate quantitation. Most of the above-mentioned problems can be overcome by the choice of adequate internal controls. The present report reviews two recently developed methods for RNA quantitation, the semi-quantitative PCR and the quantitative PCR illustrated for the measurement of monoamine oxidase (MAO) A and B mRNAs and the estrogen receptor (ER) mRNA respectively, with a particular emphasis on the design of appropriate internal controls to compensate for the intra- and inter-assay variability inherent to RT-PCR.
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79
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Maggi A, Solenghi D, Panzeri A, Borroni G, Cazzaniga M, Sangiovanni A, De Fazio C, Salerno F. Prevalence and incidence of cholelithiasis in patients with liver cirrhosis. ITALIAN JOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY 1997; 29:330-5. [PMID: 9476186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
AIMS To evaluate the prevalence, the incidence and the history of cholelithiasis in liver cirrhosis. PATIENTS AND METHODS A series of 233 consecutive cirrhotic patients (193 Child A, 35 Child B and 5 Child C) were assessed for cholelithiasis by ultrasonography. Of these, 201 (those who had never had cholecystectomy) were followed-up with repeated ultrasonographies. RESULTS The prevalence of cholelithiasis was 38% (22% gallstones and 16% previous cholecystectomies). No relationships with the usual risk factors for cholesterol gallstones, such as age, sex, body mass index, serum glucose or triglycerides, were found. On the contrary, close correlations were observed with serum albumin, bilirubin, prothrombin time and Pugh score. By multivariate analysis, only serum bilirubin was independently correlated with cholelithiasis. Histories of biliary pain were more frequent in patients with previous cholecystectomy (62% cases) than in those with gallstones (21%) and those without cholelithiasis (7%). On the contrary, complaints of dyspepsia were similar in the three groups of patients. During a mean follow-up of 34.4 +/- 0.9 months, there was a 4.9% annual rate of development of new stones in 127 patients without cholelithiasis at the first investigation. This rate is markedly higher than that reported for normal subjects in a previous survey carried out in a similar geographic area. During a mean follow-up of 31.8 +/- 1.2 months, symptoms or complications were seen in 2 out of 45 patients with initial gallstones (4.4%). The annual rate of complications was estimated to be less than 2%. CONCLUSIONS Cholelithiasis is frequently associated with cirrhosis and the risk of developing new stones remains high during the natural history of the disease.
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Dunlap DD, Maggi A, Soria MR, Monaco L. Nanoscopic structure of DNA condensed for gene delivery. Nucleic Acids Res 1997; 25:3095-101. [PMID: 9224610 PMCID: PMC146867 DOI: 10.1093/nar/25.15.3095] [Citation(s) in RCA: 331] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Scanning force microscopy was used to examine DNA condensates prepared with varying stoichiometries of lipospermine or polyethylenimine in physiological solution. For the first time, individual DNA strands were clearly visualized in incomplete condensates without drying. Using lipospermine at sub-saturating concentrations, discrete nuclei of condensation were observed often surrounded by folded loops of DNA. Similar packing of DNA loops occurred for polyethylenimine-induced condensation. Increasing the amount of the condensing agent led to the progressive coalescence or aggregation of initial condensation nuclei through folding rather than winding the DNA. At over-saturating charge ratios of the cationic lipid or polymer to DNA, condensates had sizes smaller than or equal to those measured previously in electron micrographs. Polyethylenimine condensates were more compact than lipospermine condensates and both produced more homogeneously compacted plasmids when used in a 2-4-fold charge excess. The size and morphology of the condensates may affect their efficiency in transfection.
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81
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Garnier M, Di Lorenzo D, Albertini A, Maggi A. Identification of estrogen-responsive genes in neuroblastoma SK-ER3 cells. J Neurosci 1997; 17:4591-9. [PMID: 9169520 PMCID: PMC6573342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/1997] [Accepted: 04/01/1997] [Indexed: 02/04/2023] Open
Abstract
To evaluate the role of estrogen receptor in the differentiation of cells of neural origin, we developed a molecular approach aimed at the identification of estrogen target genes by mRNA differential display PCR (ddPCR) in human neuroblastoma SK-ER3 cells. More than 3000 RNAs were examined, a few of which displayed a differential regulation pattern in response to 17beta-estradiol (E2). Sequence analysis of three differentially amplified ddPCR products showed homology with the growth-associated nuclear protein prothymosin-alpha (PTMA), the Bcl2-interacting protein Nip2, and one mRNA previously described by others in fetal human brain. Two ddPCR products, referred to as P4 and P10, corresponded to new DNA sequences. Northern analysis confirmed that estrogen treatment of SK-ER3 cells resulted in the upregulation and downregulation of expression of these messages. In particular, PTMA was found to accumulate at both 1 and 17 hr after E2 treatment, whereas P10 product accumulated only at 1 hr. Conversely, P4, Nip2, and the fetal brain-related mRNAs were significantly decreased by the treatment. Further time course analysis of PTMA and Nip2 mRNAs levels indicated that the hormone exerted a marked biphasic regulatory effect on expression of both messages during the course of cell differentiation. In the present study we report for the first time the identification of a panel of estrogen target genes in neural cells that provide new insights in the molecular mechanism of action of E2 in cells of neural origin.
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82
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Santagati S, Gianazza E, Agrati P, Vegeto E, Patrone C, Pollio G, Maggi A. Oligonucleotide squelching reveals the mechanism of estrogen receptor autologous down-regulation. Mol Endocrinol 1997; 11:938-49. [PMID: 9178753 DOI: 10.1210/mend.11.7.9936] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Antisense oligos complementary to the 5'-end, but not to the 3'-end, of the estrogen receptor (ER) messenger RNA caused a paradox accumulation of ER protein in MCF-7 cells. The same effect was observed after treatment of the cells with the corresponding sense oligos. The oligos interfering with ER down-regulation were demonstrated to specifically bind the ER with affinities in the nanomolar range. It is, therefore, proposed that the ER up-regulation induced by the oligos might be due to squelching of the ER (or ER-inducible proteins) from their binding site located in the 5'-end of the ER gene. We also report that transcriptionally inactive ER mutants can undergo down-regulation, and that in denaturing gels, the migration profile of ER-oligo and ER-estrogen-responsive element complexes are dissimilar. We, therefore, propose that ER can interact with DNA in different ways and at different binding sites. These observations might have important pharmacological consequences, since specific drugs could be devised to induce the ER conformation necessary to perform only selected tasks of the ER transcriptional repertoire.
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MESH Headings
- Animals
- Base Sequence
- Blotting, Western
- COS Cells
- DNA Primers/chemistry
- Down-Regulation/genetics
- Electrophoresis, Polyacrylamide Gel
- Gene Deletion
- Humans
- Luciferases/genetics
- Oligonucleotides/chemistry
- Oligonucleotides/genetics
- Oligonucleotides/pharmacology
- Oligonucleotides, Antisense/chemistry
- Oligonucleotides, Antisense/genetics
- Oligonucleotides, Antisense/pharmacology
- Phosphorus Radioisotopes
- Receptors, Estrogen/biosynthesis
- Receptors, Estrogen/genetics
- Receptors, Estrogen/metabolism
- Recombinant Proteins/biosynthesis
- Recombinant Proteins/genetics
- Recombinant Proteins/metabolism
- Transcription, Genetic/physiology
- Transfection/genetics
- Tumor Cells, Cultured
- Urea/chemistry
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Agrati P, Ma ZQ, Patrone C, Picotti GB, Pellicciari C, Bondiolotti G, Bottone MG, Maggi A. Dopaminergic phenotype induced by oestrogens in a human neuroblastoma cell line. Eur J Neurosci 1997; 9:1008-16. [PMID: 9182953 DOI: 10.1111/j.1460-9568.1997.tb01451.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Oestrogens are the key factor in the sexual differentiation of the mammalian brain and play an important role in the activity of selected areas of the mature brain. To pursue the study of oestrogen action on neural cells at the molecular level, we developed a human neuroblastoma cell line (SK-ER3) expressing the oestrogen receptor (ER). Treatment of these cells with 17beta-oestradiol causes growth arrest and morphological and biochemical differentiation. The aim of the present study was to investigate whether oestrogen-differentiated SK-ER3 neuroblastoma cells acquire the ability to synthesize a specific neurotransmitter and whether the growth arrest previously reported can be ascribed to the blockage of the cells at a specific stage of the cell cycle. The results presented here indicate that oestrogens induce accumulation of SK-ER3 cells in the G0 phase of the cell cycle, underscoring the acquisition of a mature neural phenotype upon hormonal treatment. Most importantly, we show that in the differentiated cells the content of tyrosine hydroxylase and Na+-dependent dopamine uptake is significantly augmented, proving that the oestrogen-differentiated SK-ER3 cells can synthesize and store a specific neurotransmitter. In addition, we prove that the dopamine accumulated in differentiated SK-ER3 cells can be released. These studies therefore suggest that oestrogen treatment results in the acquisition of a fully functional dopaminergic phenotype of SK-ER3 cells. Ample evidence shows a link between dopaminergic neurons and oestrogen activity in hypothalamic and non-hypothalamic areas of the mammalian brain. Our study indicates that oestrogens might play a primary role in committing undifferentiated neuroblasts towards the dopaminergic phenotype.
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84
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Maggi A. The discourse of sodom in a seventeenth-century Venetian text. JOURNAL OF HOMOSEXUALITY 1997; 33:25-43. [PMID: 9378941 DOI: 10.1300/j082v33n03_02] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
This essay examines L'Alcibiade fanciullo a scola, a seventeenth-century text written in Venice. L'Alcibiade is a sort of Platonic dialogue between a sodomite teacher and his young and attractive pupil. The teacher tries to convince his student to let him penetrate him. The discourse of the sodomite teacher is similar to Lacan's "discourse of the master." Maggi brings to the fore the intrinsic ambiguities of the sodomite discourse. On the one hand, since he posits himself outside society, the sodomite is able to manipulate and distort any sort of discourse. The sodomite teacher believes that women embody the religious/political power that oppresses sodomites. The master knows that any discourse exclusively aims to acquire a certain power. On the other hand, the sodomite discourse is nothing but another form of power/oppression. The master subjugates the other through his "sodomite rhetoric," based on lies and puns.
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85
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Di Lorenzo D, Ferrari F, Agrati P, de Vos H, Apostoli P, Alessio L, Albertini A, Maggi A. Manganese effects on the human neuroblastoma cell line SK-ER3. Toxicol Appl Pharmacol 1996; 140:51-7. [PMID: 8806869 DOI: 10.1006/taap.1996.0196] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
SK-ER3 cells were recently demonstrated to represent a valuable model for the study of estrogen-inducible differentiation of neural cells in culture. This system may constitute an important tool also for the analysis of the effects of neurotoxic drugs. The present study demonstrates that short term exposure to Mn causes increased proliferation rate of SK-ER3 cells regardless of their differentiation. Long term treatment causes cell death in undifferentiated cells at concentrations of the metal as low as 100 nM. When the cells are differentiated with estrogens, death is observed only with a Mn concentration two orders of magnitude higher. Measurement of neurite extension and quantitation of tyrosine hydroxylase content after long-term exposure to the metal allow the conclusion that Mn does not alter the state of differentiation of SK-ER3 cells induced by the treatment with the hormone. The study underlines the importance of studying the effect of Mn in proliferating neural cells and demonstrates the toxic role of micromolar concentrations of the metal in fully differentiated neural cells. Since other authors produced evidence of effects of the metal on cell death and proliferation only at millimolar concentrations, and none described its proliferative activity, the model utilized in the present study seems to be of particular interest.
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86
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Nicolini A, Saccheri S, Lovaria A, Maggi A, Cazzaniga M, Panzeri A, Salerno F. Prevention of variceal rebleeding and treatment of liver carcinoma by consecutive transjugular intrahepatic portosystemic shunt and hepatic artery chemoembolization. THE ITALIAN JOURNAL OF GASTROENTEROLOGY 1996; 28:269-71. [PMID: 8842845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Variceal bleeding and hepatocellular carcinoma are two severe complications of cirrhosis. One of our patients who bled from oesophageal varices was found to have a malignant hepatic nodule. As the patient refused liver transplantation, a transjugular intrahepatic portosystemic stent was carried out for portal hypertension, and transcatheter arterial chemoembolization for cancer. Both procedures were successful and one year later liver function has not deteriorated. This case shows that intrahepatic stent placement and selective arterial chemoembolization can be safely performed in cirrhotic patients with a solitary hepatocarcinoma nodule and a good liver function reserve.
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87
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Patrone C, Ma ZQ, Pollio G, Agrati P, Parker MG, Maggi A. Cross-coupling between insulin and estrogen receptor in human neuroblastoma cells. Mol Endocrinol 1996; 10:499-507. [PMID: 8732681 DOI: 10.1210/mend.10.5.8732681] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Insulin is a well known mitotic agent for neuroblastoma cells. Human SK-N-BE neuroblastoma cells stably transfected with the estrogen receptor, however, undergo growth arrest and differentiation when treated with insulin. These effects were shown to be due to an insulin-dependent activation of the unliganded estrogen receptor. Here, we demonstrate that this activation involves the AF-2 COOH-terminal domain of the estrogen receptor and that the communication between estrogen and insulin receptor systems occurs via selected and specific transduction signals. In fact, by the use of dominant negative and dominant positive mutants we demonstrate that p21ras is essential for insulin and estrogen receptor coupling. With pharmacological tools, we prove that PI 3'kinase does not contribute to this cross-talk and that protein kinase C triggers transduction signals that act in synergism with p21ras. These results prove the intricacy of all these intracellular paths of communication. The finding that, in neuroblastoma cells, selected signal transduction systems are involved in the insulin-dependent activation of estrogen receptor is of particular interest considering that estrogen receptor might restrict the role played by insulin during the differentiation of neural cells and interfere with its proliferative potential while allowing its regulation of other functions related to cell survival.
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88
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Turato R, Cavalli A, Maggi A, Tusa M, Volpi A. [Clinical history of patients hospitalized for syncope caused by isolated carotid sinus hypersensitivity]. CARDIOLOGIA (ROME, ITALY) 1996; 41:469-72. [PMID: 8767637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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89
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Braida D, Paladini E, Griffini P, Lamperti M, Maggi A, Sala M. An inverted U-shaped curve for heptylphysostigmine on radial maze performance in rats: comparison with other cholinesterase inhibitors. Eur J Pharmacol 1996; 302:13-20. [PMID: 8790986 DOI: 10.1016/0014-2999(96)00072-6] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The potential of heptylphysostigmine tartrate (pyrrolo [2,3b] indol-5-ol, 3,3a,8,8a-hexahydro-1,3a,8-trimethylheptylcarbamate [ester, (3aS-cis)]) (MF201), a new second-generation cholinesterase inhibitor, to antagonize scopolamine-induced amnesia in rats was assessed in an 8-arm radial maze. Upon completing the training session, the rats were orally administered increasing doses of MF201 (2, 3, 4, 6 and 8 mg/kg) 60 min prior to a s.c. injection of scopolamine (0.25 mg/kg). 9-Amino-1,2,3,4-tetrahydroamino-acridine hydrochloride hydrate (tacrine) (0.25, 0.37, 0.5, 1 and 2 mg/kg), 1-benzil-4-[(5,6-dimethoxy-1-indanon)-2-yl]-methyl piperidine (E2020) (0.125, 0.18, 0.25 and 0.5 mg/kg) and physostigmine (0.15, 0.25, 0.5 and 1 mg/kg) were orally administered and rats were tested in the same task. As previously described, scopolamine induced an impairment in radial maze performance, measured in terms of total number of errors, total time taken to complete the task and the percentage of amnesic animals. The reversal of scopolamine-induced impairment was characterized by the presence of an inverted U-shaped dose-response curve. A significant antagonistic effect was achieved with a dose (mg/kg) of 0.25 for E2020, 0.5 for tacrine and physostigmine and 3, 4 and 6 for MF201, the latter manifesting a broader spectrum of activity (3-6 mg/kg). While the maximal active doses restored the scopolamine-induced modified pattern of arm entry, they were ineffective in reducing hypermotility, suggesting the drugs have a specific effect on cognitive function.
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90
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Carlo P, Violani E, Del Rio M, Olasmaa M, Santagati S, Maggi A, Picotti GB. Monoamine oxidase B expression is selectively regulated by dexamethasone in cultured rat astrocytes. Brain Res 1996; 711:175-83. [PMID: 8680861 DOI: 10.1016/0006-8993(95)01353-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The influence of dexamethasone on monoamine oxidase (MAO) A and B expression and activity was investigated in primary cultures of rat type 1 astrocytes cultured under serum free, defined conditions. Dexamethasone treatment resulted in a dose- and time-dependent induction of MAO-B, but not of MAO-A, activity. The selective MAO-B increase was substantially reduced by the antagonist RU 486, thus suggesting a glucocorticoid receptor-mediated action of the hormone. Kinetic analysis showed an increase in Vmax of MAO-B with no change in apparent K(m). The dexamethasone-induced selective rise in MAO-B activity appeared to be due to enhanced enzyme synthesis, since MAO-B mRNA was markedly increased by dexamethasone treatment and the recovery of MAO-B activity after its irreversible inhibition by deprenyl was more pronounced in the presence than in the absence of the hormone. Furthermore, the dexamethasone effect was abolished by the protein synthesis inhibitors actinomycin D or cycloheximide. The present study demonstrates that dexamethasone is able to selectively induce MAO-B in type 1 astrocytes and leads to speculation of a possible role for glucocorticoids in the increase in brain MAO-B associated with neurodegenerative disorders, such as Parkinson's and Alzheimer's diseases.
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91
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Gola S, Foman C, Carpi G, Maggi A, Cassaà A, Rovere P. Inactivation of bacterial spores in phosphate buffer and in vegetable cream treated with high pressures. HIGH PRESSURE BIOSCIENCE AND BIOTECHNOLOGY, PROCEEDINGS OF THE INTERNATIONAL CONFERENCE ON HIGH PRESSURE BIOSCIENCE AND BIOTECHNOLOGY 1996. [DOI: 10.1016/s0921-0423(06)80044-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
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92
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Santagati S, Ma ZQ, Ferrarini C, Pollio G, Maggi A. Expression of early genes in estrogen induced phenotypic conversion of neuroblastoma cells. J Neuroendocrinol 1995; 7:875-9. [PMID: 8748125 DOI: 10.1111/j.1365-2826.1995.tb00729.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Estrogens are known to modulate the growth rate and differentiation state of a number of cells. In uterine, as well as in mammary tumor cells, estrogen-dependent proliferation and differentiation are correlated to a series of biochemical responses, including increased expression of proto-oncogenes such as: c-fos, c-jun and c-myc. Since estrogens were shown to regulate the proliferation and the differentiation state of cells of nervous origin, the aim of the present study was to investigate whether these effects were associated to changes in the expression of early genes. In the model system utilized, the human cell line SK-ER3, an increase in c-fos mRNA and Fos protein without change of c-jun and related genes mRNA concentration was observed after short term treatment with 17 beta-estradiol (E2). A significant decrease of c-fos, c-jun and jun-D proto-oncogene mRNA levels were found after prolonged hormonal treatment. The exposure to the hormone did not determine any change in N-myc expression. Since the three protooncogene mRNAs are rapidly induced following estrogen treatment in other cell systems and target tissues, it is concluded that the estrogen-induced differentiation of neuroblastoma cells is correlated to a pattern of expression of early genes that might be peculiar for the activity of this hormone in neural cells.
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93
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Ma ZQ, Violani E, Villa F, Picotti GB, Maggi A. Estrogenic control of monoamine oxidase A activity in human neuroblastoma cells expressing physiological concentrations of estrogen receptor. Eur J Pharmacol 1995; 284:171-6. [PMID: 8549621 DOI: 10.1016/0014-2999(95)00387-z] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Several lines of evidence support the hypothesis of a role played by estrogens in the manifestation of affective disorders in women. The analysis of the mechanism of action of a number of antidepressant drugs clearly demonstrated the involvement of the catecholaminergic system in the etiology of these complex behavioral pathologies. The present in vitro study was therefore undertaken to investigate the presence of a functional link between estrogen and catecholamine metabolism in cells of neural origin. The model system utilized was a human neuroblastoma cell line which was obtained by stable transfection of the estrogen receptor cDNA (SK-ER3). The present study shows that in SK-ER3 activation of the estrogen receptor correlates with a marked decrease in monoamine oxidase A activity. This effect is observed following treatment with a physiological concentration of 17 beta-estradiol and can be blocked by the specific antagonist of the steroid receptor, ICI 182,780. Dibutyryl cyclic AMP acting, like estrogens, on the state of differentiation of SK-ER3 cells did not affect monoamine oxidase A activity. The present study provides strong evidence of a strict relationship between estrogen receptor and monoamine oxidase A activity in human cells of neural origin, thus favoring the hypothesis of an antidepressive effect of estrogens exerted via inhibition of the monoamine oxidative pathway.
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94
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Magalini A, Ferrari F, Savoldi G, Ingrassia R, Albertini A, Pollio G, Patrone C, Maggi A, Di Lorenzo D. Specificity of action of a herpes virus VP16/tetracycline-dependent trans-activator in mammalian cell cultures. DNA Cell Biol 1995; 14:665-71. [PMID: 7646813 DOI: 10.1089/dna.1995.14.665] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
In this work, we have studied the activity of a tetracycline modulatable trans-activator (tTA) generated by fusing the DNA binding domain of the tetracycline repressor to the trans-activation domain of the Herpes simplex virus protein 16 (HSV VP16) (plasmid pUHD15-1Neo). In the three different cell lines studied (HTC, rat hepatoma; T47D, human breast cancer; SK-N-BE, human neuroblastoma), the expression of the luciferase gene under the control of a tetracycline operator sequence (plasmid pUHC13-3) was used as a control of the incorporation and the functionality of the trans-activator. Clones selected from these cells responded in a time and dose-dependent manner to the withdrawal of tetracycline. In all these clones, the tTA trans-activator not only modulates the activity of the luciferase gene, but also modulates the activity of a number of endogenous proteins, including C/EBP beta, the glucocorticoid receptor (GR), and SP1. In the transfected cells, the level of these transcription factors was strongly inhibited in the presence of tetracycline and was highly increased after tetracycline removal. Electrophoresis mobility shift assay (EMSA) and footprint experiments proved that the induced proteins are perfectly efficient in binding the DNA. Their transcriptional activity was also determined. In HTC/A9 cells, the level of the chloramphenicol acetyltransferase (CAT) expression driven by the promoter of the alpha 1-glycoprotein (AGP) gene was strongly enhanced at 72-84 hr following removal of tetracycline from the growth media. The accumulation of the endogenous AGP mRNA also increased at 84 hr. In the T47D/TA11 and SK-N-BE/C2.6 cells, a general activation of protein synthesis was also evidenced.
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95
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Leonzi O, Ettori F, Lettieri C, Metra M, Maggi A, Niccoli L. [Coronary angioplasty in chronic total occlusion: angiography results, complications, and predictive factors]. GIORNALE ITALIANO DI CARDIOLOGIA 1995; 25:807-14. [PMID: 7557030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The results of coronary angioplasty of chronic total occlusions are still controversial. We examined baseline clinical and angiographic parameters and the success and complication rates of 142 consecutive procedures of coronary angioplasty of chronic occlusions selected among 1084 total procedures performed between January 1989 and May 1993. Procedural success was obtained in 109 procedures (77%) with 4 major cardiac complications (2.8%) consisting in one cardiac death caused by left main artery occlusion following an attempt of dilatation of an occluded left anterior descending artery, two non Q wave myocardial infarctions caused by distal embolization and one cardiac tamponade following artery perforation, successfully treated by pericardiocentesis. Extensive coronary dissection occurred in 24 procedures (17%): 5 caused vessel reocclusion and 19 were successfully treated by prolonged balloon inflation and/or use of long balloons or stent implantation. Among 15 baseline clinical and angiographic variables, none was predictive of cardiac complications or coronary artery dissection. In contrast, procedural success was significantly related with absence of bridging collaterals, duration of occlusion < 3 months and a tapered or thrombotic morphology of occlusion. Presence or absence of collaterals was the most significant variable selected by multivariate discriminant analysis. When patients with bridging collaterals were excluded from the analysis, occlusion morphology was the most important determinant. Success rates were 95% and 82% in patients with a tapered morphology lesion with < 3 months and > 3 months duration, respectively (ns); in contrast, success rates were 79% and 36% in patients with abrupt occlusion morphology of < and > 3 months duration (p = 0.001).
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96
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Bardelli G, Maggi G, Maggi A, Barlera S. [Successive ischemic events to a first acute myocardial infarct treated with fibrinolysis. An analysis of GISSI-2 patients considered reperfused by a clinical criterion. Participants in the GISSI-2 study. Gruppo Italiano per lo Studio della Streptochinasi nell'Infarto Miocardico]. GIORNALE ITALIANO DI CARDIOLOGIA 1995; 25:463-72. [PMID: 7642053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
BACKGROUND The fast normalisation of the ST, after thrombolysis, is early sign related to coronary artery reperfusion and to prognosis of acute myocardial infarction (AMI). The aim of this analysis is the evaluation, in the large patients cohort of the GISSI-2 trial, of the relationship between the ST segment evolution after fibrinolytic therapy of AMI and recurrent ischaemic events [angina-reinfarction-ischaemia to exercise testing (ET)] at 30 and 180 days from randomisation. METHODS Patients with first confirmed IMA and ECG before randomisation and 4 hours later, are chosen from GISSI-2 trial. A decrease > or = 50% of the sigma ST elevation is adopted as cutoff for predicting coronary artery patency. Recanalisation is deemed to have occurred in group A patients versus not reperfused group B patients. The studied events are: angina, reinfarction, mortality, at 30 and 180 days from randomisation; ischemia to ET SL of 4-6 week. The results are presented in terms of Mantel-Haenszel odds ratios (OR) and 95% confidence intervals. RESULTS Group A patients n. 5307 experienced versus group B patients n. 2718 a higher incidence of--in-hospital angina: 10.3% vs 7.9% OR 1.30 (1.11-1.52)-180 days reinfarction: 2.9% Vs 1.7% OR 1.66 (1.19-2.30)-Ischaemia to ET 25.4% vs 21.4% OR 1.24 (1.08-1.43), and a lower in-hospital mortality: 3.8% vs 8.5% OR 0.39 (0.32-0.48). CONCLUSIONS Patients having indirect signs of early reperfusion post thrombolysis for IMA experience a higher in-hospital and 180 days recurrent ischaemia and a lower mortality; this fact can allow early identification of the patients who can receive a benefit from different therapeutical strategies.
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97
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Ma Z, Violani E, Villa F, Picotti G, Maggi A. MAO-A activity is modulated by estrogens in the human neuroblastoma cell line SK-ER3. Pharmacol Res 1995. [DOI: 10.1016/1043-6618(95)86685-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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98
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Patrone C, Ma Z, Agrati P, Vegeto E, Maggi A. RAS mediates the insulin-dependent activation of the unliganded estrogen receptor in human neuroblastoma cells. Pharmacol Res 1995. [DOI: 10.1016/1043-6618(95)86536-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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99
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Salerno F, Moser P, Maggi A, Vitaliani G, Benetti G. Effects of long-term administration of low-dose lactitol in patients with cirrhosis but without overt encephalopathy. J Hepatol 1994; 21:1092-6. [PMID: 7699233 DOI: 10.1016/s0168-8278(05)80623-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
To investigate the efficacy and the acceptability of different doses of lactitol in patients with subclinical hepatic encephalopathy, 28 patients with cirrhosis were enrolled in a controlled clinical trial comparing 5-month therapies with lactitol at two different doses: 0.3 and 0.5 g/kg bw per day. This period was followed by 1 month of recovery. Patients were monitored with venous blood ammonia determination, three psychometric tests, clinical evaluation of mental status and EEG. The porto-systemic encephalopathy index of Conn was determined periodically. Twenty-two patients completed the trial (11 for each dose of lactitol). Both doses of lactitol decreased plasma ammonia levels and improved the porto-systemic encephalopathy index. The higher dose was more effective in improving performance in the psychometric tests. After the period of recovery, both the porto-systemic encephalopathy index and the psychometric test scores returned to pretreatment values. Lactitol was tolerated well by patients. Three patients given the higher dose reported periodic intestinal discomfort, but did not stop taking lactitol or reduce the dosage; no side-effects were reported by the patients taking the lower dose. These results indicate that lactitol in doses ranging from 0.3 to 0.5 g/kg bw is a well-tolerated and effective treatment for subclinical encephalopathy.
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100
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Santagati S, Melcangi RC, Celotti F, Martini L, Maggi A. Estrogen receptor is expressed in different types of glial cells in culture. J Neurochem 1994; 63:2058-64. [PMID: 7964723 DOI: 10.1046/j.1471-4159.1994.63062058.x] [Citation(s) in RCA: 124] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Estrogens derived from the aromatization of androgens are believed to be responsible for the induction of the sexual differentiation of the CNS interacting with specific estrogen receptors (ER) present in developing neurons. However, the brain cellular distribution of ER is not so well documented. The aim of this study was to investigate the qualitative and quantitative expression of ER mRNA in well characterized cultures of rat type 1 and type 2 astrocytes and of oligodendrocytes by polymerase chain reaction. A series of amplifications with a set of primers spanning along the entire ER mRNA was utilized in the different types of glial cells, in a positive control (uterus), and in a negative control (SK-N-BE cell line) previously shown to be devoid of ER. The data obtained show that ER mRNA is expressed in all three types of glial cell analyzed in almost equal amounts, which are 25-50 times lower than those in the uterus. The mRNA expressed in the glia is homologous with that expressed in the uterine tissue.
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