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1.
Urolithiasis ; 51(1): 16, 2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36512096

RESUMO

The occurrence of asymptomatic bacteriuria concomitant to urolithiasis is an issue for patients undergoing renal stone treatment. Disposing of a preoperative urine culture is essential to reduce the risk of septic events. The endpoint of the study is to report which characteristics of candidates for renal stone treatment are frequently associated with positive urine culture. 2605 patients were retrospectively enrolled from 14 centers; inclusion criteria were age > 18 and presence of a single renal stone 1-2 cm in size. The variables collected included age, gender, previous renal surgery, comorbidities, skin-to-stone distance, stone size, location, density, presence of hydronephrosis. After a descriptive analysis, the association between continuous and categorical variables and the presence of positive urine culture was assessed using a logistic regression model. Overall, 240/2605 patients (9%) had preoperative bacteriuria. Positive urine culture was more frequent in females, patients with previous renal interventions, chronic kidney disease, congenital anomalies, larger stones, increased density. Multivariate analysis demonstrated that previous renal interventions (OR 2.6; 95% CI 1.9-3.4; p < 0.001), renal-related comorbidities (OR 1.31; 95% CI 1.19-1.4; p < 0.001), higher stone size (OR 1.06; 95% CI 1.02-1.1; p = 0.01) and density (OR 1.00; 95% CI 1.0-1.00; p = 0.02) were associated with bacteriuria; male gender and lower caliceal location were inversely related to it. Beyond expected risk factors, such as female gender, other parameters are seemingly favoring the presence of positive urine culture. The awareness of variables associated with bacteriuria allows to assess which individuals are at increased risk of presenting bacteriuria and reduce the rate of septic complications.


Assuntos
Bacteriúria , Cálculos Renais , Urolitíase , Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Bacteriúria/epidemiologia , Estudos Retrospectivos , Cálculos Renais/cirurgia , Urolitíase/epidemiologia , Fatores de Risco
2.
J Endocrinol Invest ; 41(5): 583-590, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29090431

RESUMO

PURPOSE: To evaluate the efficacy of alpha-lipoic acid (ALA) administration on hormonal and metabolic parameters of obese PCOS patients. METHODS: A group of 32 obese PCOS patients were selected after informed consent. 20 patients referred to have first grade relatives with diabetes type I or II. Hormonal and metabolic parameters as well as OGTT were evaluated before and after 12 weeks of ALA integrative administration (400 mg per os every day). RESULTS: ALA administration significantly decreased insulin, glucose, BMI and HOMA index. Hyperinsulinemia and insulin response to OGTT decreased both as maximal response (Δmax) and as AUC. PCOS with diabetes relatives showed the decrease also of triglyceride and GOT. Interestingly in all PCOS no changes occurred on all hormonal parameters involved in reproduction such as LH, FSH, and androstenedione. CONCLUSIONS: ALA integrative administration at a low dosage as 400 mg daily improved the metabolic impairment of all PCOS patients especially in those PCOS with familiar diabetes who have a higher grade of risk of NAFLD and predisposition to diabetes.


Assuntos
Antioxidantes/administração & dosagem , Diabetes Mellitus/tratamento farmacológico , Resistência à Insulina , Obesidade/tratamento farmacológico , Síndrome do Ovário Policístico/tratamento farmacológico , Ácido Tióctico/administração & dosagem , Adulto , Índice de Massa Corporal , Diabetes Mellitus/patologia , Feminino , Seguimentos , Humanos , Obesidade/complicações , Obesidade/patologia , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/patologia , Prognóstico , Adulto Jovem
3.
Minerva Ginecol ; 66(3): 313-24, 2014 Jun.
Artigo em Italiano | MEDLINE | ID: mdl-24971788

RESUMO

The putative role and use of dehydroepiandrosterone (DHEA) as replacement therapy for menopausal women has been under consideration during the latest years. DHEA is one of the main adrenal hormones that progressively reduces its plasmatic levels from the beginning of ageing. This phenomenon implies not only the reduction of the plasmatic androgens but also the decrease of a peculiar category of hormones, named neurosteroids, in particular one: allopregnanolone. This review aims to elucidate the peculiar aspects of DHEA administration and its putative use as substitutive/integrative hormonal treatment alone or in combination with the traditional hormone replacement therapy.


Assuntos
Desidroepiandrosterona/administração & dosagem , Terapia de Reposição Hormonal/métodos , Menopausa , Envelhecimento/fisiologia , Desidroepiandrosterona/sangue , Feminino , Humanos
4.
J Dent Res ; 92(12 Suppl): 161S-7S, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24158337

RESUMO

The aim of this study was to compare the release of bone markers during osseointegration of immediately loaded and nonloaded implants. Forty patients who were indicated for rehabilitation with dental implants randomly received either implant and prosthesis placement within 72 hours (group IM) or implant insertion and no prosthesis placement (group NL). Peri-implant crevicular fluid was collected immediately after implant insertion and 7, 15, 30, 60, 90, and 120 days after surgery and levels of osteoprotegerin, transforming growth factors, osteocalcin, osteopontin, and parathyroid hormone were evaluated using Luminex assay. Bleeding index and peri-implantar sulcus depth were also evaluated. The data were compared using statistical tests (α = 5%). No statistical difference was found regarding demographic and clinical parameters (p > .05). Transforming growth factors, osteoprotegerin, osteopontin, and parathyroid hormone presented an earlier release peak in group IM than in NL group (p < .05). Osteocalcin achieved higher levels in group IM versus group NL between 7 and 30 days of evaluation (p < .05). It may be concluded that earlier loading positively modulates bone mediators release around immediately loaded implants when compared with nonloaded dental implants.


Assuntos
Osso e Ossos/química , Implantes Dentários , Carga Imediata em Implante Dentário , Osseointegração/fisiologia , Adolescente , Adulto , Idoso , Biomarcadores/análise , Implantação Dentária Endóssea/métodos , Seguimentos , Líquido do Sulco Gengival/química , Hemorragia Gengival/classificação , Humanos , Pessoa de Meia-Idade , Osteocalcina/análise , Osteopontina/análise , Osteoprotegerina/análise , Hormônio Paratireóideo/análise , Índice Periodontal , Bolsa Periodontal/classificação , Estudos Prospectivos , Fator de Crescimento Transformador alfa/análise , Adulto Jovem
5.
Med Chem ; 4(3): 219-28, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18473914

RESUMO

Arbutus unedo L. has been for a long time employed in traditional and popular medicine as an astringent, diuretic, urinary anti-septic, and more recently, in the therapy of hypertension and diabetes. Signal transducer and activator of transcription 1 (STAT1) is a fascinating and complex protein with multiple yet contrasting transcriptional functions. Although activation of this nuclear factor is finely regulated in order to control the entire inflammatory process, its hyper-activation or time-spatially erroneous activation may lead to exacerbation of inflammation. The modulation of this nuclear factor, therefore, has recently been considered as a new strategy in the treatment of inflammatory diseases. In this study, we present data showing that the aqueous extract of Arbutus unedo's leaves exerts inhibitory action on interferon-gamma (IFN-gamma) elicited activation of STAT1, both in human breast cancer cell line MDA-MB-231 and in human fibroblasts. This down-regulation of STAT1 is shown to result from a reduced tyrosine phosphorylation of STAT1 protein. Evidence is also presented indicating that the inhibitory effect of this extract may be mediated through enhancement of tyrosine phosphorylation of SHP2 tyrosine phosphatase. The modulation of this nuclear factor turns out into the regulation of the expression of a number of genes involved in the inflammatory response such as inducible nitric oxide synthase (iNOS) and intercellular adhesion molecule-1 (ICAM-1). Taken together, our results suggest that the employment of the Arbutus unedo aqueous extract is promising, at least, as an auxiliary anti-inflammatory treatment of diseases in which STAT1 plays a critical role.


Assuntos
Ericaceae , Fibroblastos/efeitos dos fármacos , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Fator de Transcrição STAT1/metabolismo , Neoplasias da Mama , Linhagem Celular Tumoral , Células Cultivadas , Ativação Enzimática , Feminino , Fibroblastos/metabolismo , Humanos , Molécula 1 de Adesão Intercelular/biossíntese , Interferon gama/farmacologia , Janus Quinase 2/metabolismo , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II/biossíntese , Fosforilação , Extratos Vegetais/farmacologia , Fator de Necrose Tumoral alfa/farmacologia , Água
6.
Int J Antimicrob Agents ; 31(1): 55-7, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17923393

RESUMO

During 2005-2006, a total of 865 Enterococcus faecium isolated from patients from eight Greek hospitals were tested for susceptibility to quinupristin/dalfopristin (Q/D). Among them, 250 genetically unrelated strains (28.9%) were found to be intermediate-resistant to Q/D (minimum inhibitory concentration (MIC) 1.5-4 mg/L); all were resistant to dalfopristin (MIC=16-64 mg/L), whilst 69% were resistant to quinupristin, carrying the ermB gene. No strain was found to carry any of the known genes, such as vatE and vatD, involved in Q/D resistance, indicating that a non-transferable undetermined mechanism is responsible for the expression of low-level Q/D resistance. The high percentage of Q/D-intermediate-resistant E. faecium in Greece was not associated with prior consumption of the agent or with the veterinary use of virginiamycin.


Assuntos
Farmacorresistência Bacteriana , Enterococcus faecium/efeitos dos fármacos , Infecções por Bactérias Gram-Positivas/microbiologia , Virginiamicina/farmacologia , Acetiltransferases/genética , Proteínas de Bactérias/genética , Enterococcus faecium/isolamento & purificação , Grécia , Humanos , Testes de Sensibilidade Microbiana
7.
J Neurosurg Sci ; 51(1): 1-9, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17369785

RESUMO

AIM: Results of prior experimental studies show that nitric oxide (NO) plays an important role in the pathogenesis of vasospasm. In the present study, the expression of endothelial NO synthase (eNOS), neuronal NO synthase (nNOS) and of inducible NO synthase (iNOS) in the human brain after subarachnoid haemorrhage were studied. METHODS: Twenty-three samples of gyrus rectus or temporal operculum that were obtained during a surgical approach to anterior circulation aneurysms were used for this study. Seven samples were obtained during surgery from patients who underwent operation for unruptured aneurysms (control group). eNOS-mRNA, nNOS-mRNA and iNOS-mRNA were extracted and amplified by RT-PCR. Patients were subdivided for intergroup comparison by: age < 60 / > 60 years; source of sample; clinical grading; extent of subarachnoid clot; presence of intracerebral/intraventricular hematoma; surgical timing; vasospasm; outcome. RESULTS: There was a significant increase in the expression of eNOS between SAH and control groups (P=0.046); eNOS hyperexpression was higher in the patients in poor clinical conditions (P=0.002) and lasted until the late phase of haemorrhage. nNOS overall expression was unchanged but hyperexpression was observed in the patients in poor clinical conditions (P=0.008). There was a significant hyperexpression of iNOS in SAH group (P=0.026), and in patients with vasospasm (P=0.0024); the expression was significantly reduced in the late phase of haemorrhage (P=0.0038). CONCLUSIONS: The acute decrease of NO after SAH is not determined by reduced constitutive NOS expression and iNOS induction is a consequence of SAH and plays a major role in the pathogenesis of vasospasm.


Assuntos
Encéfalo/enzimologia , Óxido Nítrico Sintase/genética , Óxido Nítrico/metabolismo , Hemorragia Subaracnóidea/enzimologia , Adulto , Idoso , Biomarcadores/metabolismo , Encéfalo/fisiopatologia , Artérias Cerebrais/enzimologia , Artérias Cerebrais/fisiopatologia , Progressão da Doença , Feminino , Regulação Enzimológica da Expressão Gênica/fisiologia , Humanos , Isoenzimas/genética , Masculino , Pessoa de Meia-Idade , Óxido Nítrico Sintase Tipo I/genética , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo III/genética , RNA Mensageiro/metabolismo , Hemorragia Subaracnóidea/fisiopatologia , Regulação para Cima/fisiologia , Vasoespasmo Intracraniano/enzimologia , Vasoespasmo Intracraniano/fisiopatologia
9.
Amino Acids ; 19(1): 229-37, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11026494

RESUMO

Poly(ADP-ribose) polymerase (PARP) is activated in glutamate-induced toxicity of neurons in culture (Cosi et al., 1994). Since injection of the excitatory amino acid, kainic acid (KA) into the rat striatum induces a delayed neuronal death, the effects of this in vivo excitotoxin lesioning procedure on striatal PARP activity was investigated. PARP activity was measured in striatal extracts both in the absence ("endogenous" activity) and presence ("total" activity) of exogenously-added fragmented DNA. KA (5nmols/1microl) produced significant and time-dependent changes in striatal PARP activity, compared to saline-injected control animals: no changes at 6h after intrastriatal KA, a 68% and 48% decrease in endogenous and total PARP activity respectively at 12h, a doubling in endogenous PARP activity at 24h, and a 382% and 60% increase in endogenous and total activities at 1 week after KA. PARP cleavage was not detected at any time point. These results suggest a participation of PARP in KA-induced toxicity in the brain in vivo.


Assuntos
Corpo Estriado/efeitos dos fármacos , Ácido Caínico/farmacologia , Poli(ADP-Ribose) Polimerases/metabolismo , Animais , Corpo Estriado/enzimologia , Ativação Enzimática , Masculino , Ratos , Ratos Sprague-Dawley
10.
Mol Carcinog ; 25(4): 256-61, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10449032

RESUMO

The steady-state levels of mRNA for the poly(ADP-ribose)polymerase (PARP), c-myc, p53, and histone H3 genes were investigated in 31 high-grade B-cell lymphomas by northern blot analysis. The panel included 15 nodal large B-cell lymphomas, nine mediastinal large B-cell lymphomas, and seven sporadic Burkitt's lymphomas. The PARP mRNA level was significantly higher in lymphomas than in control tissues and corresponded with the amount of PARP protein, as assessed by immunoblot analysis in six samples. The level of PARP mRNA was positively correlated with that of p53 mRNA. No correlation was found between the mRNA expression levels of PARP and histone H3, suggesting that PARP expression levels are independent of the proliferation rate of neoplastic cells. In this setting, the strong correlation between PARP and p53 suggests that the high expression of PARP may be associated with ongoing DNA damage in high-grade lymphomas.


Assuntos
Genes p53 , Linfoma de Células B/enzimologia , Linfoma de Células B/genética , Linfoma não Hodgkin/enzimologia , Linfoma não Hodgkin/genética , Poli(ADP-Ribose) Polimerases/metabolismo , Adolescente , Adulto , Idoso , Sequência de Bases , Divisão Celular/genética , Criança , Pré-Escolar , Primers do DNA , Feminino , Genes myc , Humanos , Linfoma de Células B/patologia , Linfoma não Hodgkin/patologia , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/genética
11.
Life Sci ; 63(23): 2097-105, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9839533

RESUMO

Previous studies have shown a role for nitric oxide (NO) as a cytotoxic effector. In the present work, two chemically different NO-donors such as glyceryl trinitrate (GTN) and S-nitroso-N-acetylpenicillamine (SNAP) were evaluated for both NO release and cytostatic/cytotoxic properties. Nitrite accumulation in the supernatant of MCF-7 and U251 cell lines indicated a greater and quickly release of NO derived from SNAP. A time-course of hemoglobin absorption spectral changes showed a greater release of NO derived from GTN in presence of cells compared to the values observed in the media, confirming that the release of NO by GTN can be enzymatic and non-enzymatic. On the contrary, SNAP generated NO without contribution of cellular components and saturated oxyhemoglobin quickly, within 2 hours. Both NO-donors inhibited thymidine incorporation in a similar manner and dose-dependently in U251 cells, but not in MCF-7 cells, where SNAP at the highest tested dose of 1000 microM induced only a 33% cytostatic effect. About trypan blue exclusion test, after 24 h GTN and SNAP, releasing similar amounts of NO, showed comparable cytotoxic effects on U251 cells (50% dead cells), but not on MCF-7 cells, where GTN resulted more cytotoxic. From our data, the "in vitro" antitumoral activity of NO-donors seems to be related to the type of tumor cell lines, to the amount and duration of NO release.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Inibidores Enzimáticos/toxicidade , Doadores de Óxido Nítrico/toxicidade , Óxido Nítrico/metabolismo , Nitroglicerina/toxicidade , Penicilamina/análogos & derivados , Biotransformação , Neoplasias Encefálicas/patologia , Neoplasias da Mama/patologia , Inibidores Enzimáticos/farmacocinética , Feminino , Glioblastoma/patologia , Humanos , Cinética , Doadores de Óxido Nítrico/farmacocinética , Nitroglicerina/farmacocinética , Penicilamina/farmacocinética , Penicilamina/toxicidade , S-Nitroso-N-Acetilpenicilamina , Células Tumorais Cultivadas
12.
J Prosthet Dent ; 80(2): 249-52, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9710831

RESUMO

This article describes the use of three devices that replace the wax rims in the registration of the intermaxillary position and of the vertical dimension of occlusion in completely edentulous patients who have been treated with Brånemark implants. The devices consist of a mechanical "tooth" that can be adjusted in all three dimensions of space and of two plates that support the registration material. The mechanical tooth is connected to an abutment in the anterior region and a contact is established with a tooth in the opposite jaw at the vertical dimension in which the patient will be restored. This allows the operator to position the mandible in the centric relation in a condition of neuromuscular deprogramming and in the absence of posterior interferences. The two metal plates are then fixed to the posterior abutments, one on each side, and support the wax and zinc oxide eugenol paste used to register the intermaxillary position just established.


Assuntos
Implantes Dentários , Oclusão Dentária , Planejamento de Dentadura/instrumentação , Registro da Relação Maxilomandibular/instrumentação , Arcada Edêntula/reabilitação , Relação Central , Dente Suporte , Articuladores Dentários , Humanos , Incisivo , Mandíbula/anatomia & histologia , Dimensão Vertical , Ceras , Cimento de Óxido de Zinco e Eugenol
13.
Hepatology ; 25(3): 585-92, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9049203

RESUMO

Our previous studies have shown a different pattern of immediate early gene and growth factor gene expression between compensatory liver regeneration occurring after cell loss/death and direct hyperplasia induced by primary mitogens. In the present study, modifications in the activation of two transcription factors, NF-kappaB and AP-1; steady-state levels of tumor necrosis factor alpha (TNF-alpha) messenger RNA (mRNA); and induction of the inducible nitric oxide synthase (iNOS) were examined in rat liver during different types of cell proliferation. Compensatory regeneration was induced in male Wistar rats by partial hepatectomy of two thirds (PH) or a necrogenic dose of CCl4 (2 mL/kg), whereas direct hyperplasia was induced by a single administration of the primary mitogens lead nitrate (LN, 100 micromol/kg), cyproterone acetate (CPA, 60 mg/kg), or nafenopin (NAF, 200 mg/kg). Liver regeneration after treatment with CCl4 was associated with an increase in steady-state levels of TNF-alpha mRNA, activation of NF-kappaB and AP-1, and induction of iNOS. A strong and prolonged activation of NF-kappaB but not of AP-1 was observed in LN-induced hyperplasia. LN also induced an increase in hepatic levels of TNF-alpha and iNOS mRNA. On the other hand, direct hyperplasia induced by two other primary mitogens, NAF and CPA, occurred in the complete absence of modifications in the hepatic levels of TNF-alpha mRNA, activation of NF-kappaB and AP-1, or induction of iNOS, although the number of hepatocytes entering S phase 18 to 24 hours after NAF was similar to that seen after PH. These results add further support to the hypothesis that cell proliferation occurring in the absence of cell loss/death may be triggered by unknown signaling pathways different from those responsible for the transition of hepatocytes from G0 to G1 after PH or cell necrosis.


Assuntos
Acetato de Ciproterona/farmacologia , Hepatectomia , Regeneração Hepática/efeitos dos fármacos , Fígado/efeitos dos fármacos , NF-kappa B/metabolismo , Nafenopina/farmacologia , Fator de Transcrição AP-1/metabolismo , Animais , Ligação Competitiva , Tetracloreto de Carbono/toxicidade , Divisão Celular/efeitos dos fármacos , Hiperplasia/induzido quimicamente , Chumbo/toxicidade , Fígado/patologia , Masculino , Mitógenos/toxicidade , Nitratos/toxicidade , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Fator de Necrose Tumoral alfa/metabolismo
14.
FEBS Lett ; 379(3): 279-85, 1996 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-8603706

RESUMO

12-O-Tetradecanoylphorbol 13-acetate (TPA) elicited a transient increase in the transcription of the inducible nitric oxide synthase (iNOS) gene coupled with a shortening of the half-life of its mRNA in primary neonatal rat hepatocytes. These effects of TPA were preceded by a surge in nuclear translocation of the transcription factor NF-kappa B, and followed by a mounting accumulation of NO-2 in the growth medium. Even cycloheximide (CHX) added by itself elicited an early, sustained activation of NF-kappa B followed by an intense induction of iNOS gene expression, irrespective of what degree of protein synthesis inhibition was brought about by the several concentrations tested. When given together, TPA and CHX exerted additive effects on hepatocellular iNOS mRNA levels. These results suggest the likelihood of an ordered sequence of events by which an activated NF-kappa B mediates the induction of iNOS gene expression in TPA- and/or CHX-treated primary hepatocytes.


Assuntos
Cicloeximida/farmacologia , Fígado/metabolismo , NF-kappa B/genética , Óxido Nítrico Sintase/genética , Acetato de Tetradecanoilforbol/farmacologia , Animais , Sequência de Bases , Regulação da Expressão Gênica/efeitos dos fármacos , Fígado/citologia , Fígado/efeitos dos fármacos , Dados de Sequência Molecular , NF-kappa B/metabolismo , Óxido Nítrico Sintase/metabolismo , Ratos , Ratos Wistar , Transcrição Gênica
15.
Br J Pharmacol ; 116(2): 1713-4, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8528547

RESUMO

Nitroflurbiprofen (NFP) causes significantly less gastric lesions than flurbiprofen (FP), probably because of its capacity to release nitric oxide (NO) in the stomach. Lipopolysaccharide (LPS), which induces the expression of an inducible type of NO synthase (iNOS) in rat stomach, also reduces gastric mucosal damage elicited by FP. Furthermore, both FP and NFP decrease significantly the amount of mRNA encoding iNOS induced by LPS in the stomach. The inhibitory effect of NFP seems to be due at least in part to its ability to release NO.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Flurbiprofeno/análogos & derivados , Flurbiprofeno/farmacologia , Óxido Nítrico/metabolismo , Estômago/efeitos dos fármacos , Animais , Feminino , Óxido Nítrico Sintase/efeitos dos fármacos , RNA Mensageiro/biossíntese , Ratos , Ratos Sprague-Dawley
16.
Adv Neuroimmunol ; 5(4): 379-410, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8746512

RESUMO

Many of the known roles of arginine (e.g. in immune function, wound healing, and protection against ammonia intoxication) are mediated by a metabolic pathway synthesising nitric oxide (NO) in the liver. Contrary to some of the current views, liver-produced NO may be basically beneficial, as it exerts both protective actions against tissue injury and cytotoxic effects on invading microorganisms, parasites, or tumor cells. An ongoing equilibrium between NO and other NO-reactive compounds (e.g. O2 and non-heme iron-sulphur-containing moieties) appears to be important in this respect, even under critical conditions. Thus, NO may prevent liver tissue harm from oxidant stress. Only when this putative counterbalance is upset by an uncontrolled, prolonged and/or massive production of NO, liver tissue damage may occur leading to hepatic inflammation or even tumor development. Moreover, the currently available data support the working hypothesis that hepatocytes partake not only to immunoregulatory processes, but even to immune defence mechanisms. Thus, the liver constitutes an excellent model for investigations into the crosstalks regulating the production of NO which take place among not only the various networks operating inside a single hepatic cell, but even the individual types of liver cells.


Assuntos
Apoptose/fisiologia , Óxido Nítrico/fisiologia , Animais , Apoptose/efeitos dos fármacos , Encéfalo/metabolismo , Dano ao DNA , Endotélio Vascular/metabolismo , Indução Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Radicais Livres , Genes p53 , Ácido Glutâmico/toxicidade , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Necrose , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Óxido Nítrico/toxicidade , Óxido Nítrico Sintase/metabolismo , Pâncreas/efeitos dos fármacos , Pâncreas/metabolismo , Receptores de N-Metil-D-Aspartato/efeitos dos fármacos , Transdução de Sinais/fisiologia
17.
Neurosci Lett ; 182(2): 295-8, 1994 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-7715831

RESUMO

Data from a previous report [3] demonstrated that the proto-oncogene c-fos mRNA expression undergoes basally a circadian fluctuation in the rat brain. The present study was designed to verify by means of Northern blot hybridization the eventual occurrence of a spontaneous oscillation in the expression of other two proto-oncogenes, jun B and c-jun, during 24 h. Rats were either entrained to a light-dark photoperiod or maintained under constant darkness or light. During the dark period, as well as the subjective night, the jun B mRNA levels in the cerebral cortex and striatum were 4-6 times higher than in the light hours or subjective day. No consistent oscillation was found in the c-jun mRNA expression during 24 h in any of the examined brain regions. These results suggest the possibility of different interactions of the c-fos, jun B and c-jun gene products throughout a 24-h period in discrete brain regions.


Assuntos
Córtex Cerebral/fisiologia , Proteínas Proto-Oncogênicas c-fos/genética , Proteínas Proto-Oncogênicas c-jun/genética , Animais , Encéfalo/fisiologia , Ritmo Circadiano , Expressão Gênica , Hipocampo/fisiologia , Masculino , RNA Mensageiro , Ratos , Ratos Wistar
18.
Eur J Biochem ; 220(2): 607-14, 1994 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-8125121

RESUMO

A cDNA spanning the entire coding region for poly(ADP-ribose) polymerase (PARP) of Sarcophaga peregrina was isolated and the nucleotide sequence was determined. The longest open reading frame encodes a polypeptide of 996 amino acid residues with a molecular mass of 113,033 Da. The similarities to the human PARP in amino acid sequence were relatively low in the DNA-binding and auto-modification domains, but very high in the C-terminal catalytic domain: identity of amino acids is 34% in the N-terminal DNA-binding domain (residues 1-369), 27% in the auto-modification domain (residues 370-507), and 56% in the C-terminal NAD-binding domain (residues 508-996). Two zinc-fingers (C-X2-C-X28-H-X2-C and C-X2-C-X31-H-X2-C)2 and a basic region in the N-terminal DNA-binding domain recognized in other PARP are conserved. Downstream of the basic region, another cysteine-rich motif (C-X2-C-X13-C-X9-C), a putative zinc-finger, was found to be well conserved in the PARP of Sarcophaga, Drosophila and human. A leucine-zipper motif (L-X6-L-X6-L-X6-L) which was found in the auto-modification domain of Drosophila PARP, is disrupted in the Sarcophaga enzyme: the second leucine is replaced by proline, and the third leucine by valine. Full-length cDNA for Sarcophaga PARP was cloned into an expression plasmid and expressed in Escherichia coli. A lysate of E. coli cells containing expressed protein reacted with antibody against Sarcophaga PARP, and PARP activity was detected. Thus, we conclude that isolated cDNA encodes a functional Sarcophaga PARP cDNA.


Assuntos
Dípteros/enzimologia , Poli(ADP-Ribose) Polimerases/biossíntese , Sequência de Aminoácidos , Animais , Sequência de Bases , Sítios de Ligação , Bovinos , Galinhas , Clonagem Molecular , Sequência Consenso , DNA/metabolismo , Primers do DNA , DNA Complementar/metabolismo , Proteínas de Ligação a DNA/biossíntese , Dípteros/genética , Drosophila/enzimologia , Expressão Gênica , Humanos , Zíper de Leucina/genética , Camundongos , Dados de Sequência Molecular , Poli(ADP-Ribose) Polimerases/genética , Reação em Cadeia da Polimerase , Mapeamento por Restrição , Homologia de Sequência de Aminoácidos , Dedos de Zinco/genética
19.
Chronobiologia ; 21(1-2): 93-7, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7924645

RESUMO

The Fos and Jun proteins are encoded by proto-oncogenes acting as immediate early genes in that they are rapidly induced by different kinds of stimuli in the nervous system. These two proteins bind to DNA regulating gene transcription, and thus determining the specificity of the neuronal response to the applied stimulation. We investigated whether the expression of these genes undergoes a variation during 24h in the absence of exogenous stimulation. Male Wistar adult (200 gr. body weight) rats, kept under a 12h/12h light-dark cycle, were sacrificed every 4h starting at 0700. The expression of c-fos, c-jun and jun B mRNAs was studied in six different brain areas by means of Northern blot hybridization, c-fos expression was also studied with in situ hybridization and immunohistochemistry. In basal conditions c-fos expression displayed a highly significant spontaneous oscillation, with the highest level during the darkness hours and the lowest during the light hours. Parallel levels of jun B expression were found in the cortex and striatum, whereas c-jun mRNA remained constantly high throughout 24 h. The periodicity of c-fos and jun B oscillation persisted also when the animals were exposed for 6 days to constant (24h/24h) light or darkness. Such oscillation could instead be inverted by manipulating the rest-activity cycle, i.e. keeping the animals awake during the light hours and allowing them to sleep during the dark hours. We then verified whether the expression of fos and jun could be correlated with states of wakefulness (W) and sleep (S), monitored with EEG recording under behavioral control.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Ritmo Circadiano/genética , Expressão Gênica , Sono/genética , Animais , Encéfalo/metabolismo , Córtex Cerebral/metabolismo , Ritmo Circadiano/fisiologia , Genes fos , Genes jun , Masculino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Sono/fisiologia , Fases do Sono/genética , Fases do Sono/fisiologia , Distribuição Tecidual , Vigília/genética , Vigília/fisiologia
20.
Eur J Neurosci ; 5(8): 1071-8, 1993 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-8281311

RESUMO

The basal expression of the proto-oncogene c-fos was studied by Northern blot analysis in different regions of the rat brain during 24 h. A striking spontaneous oscillation of c-fos mRNA expression was detected in animals kept in basal conditions with a 12 h light/12 h dark cycle. In these animals c-fos mRNA was just detectable during the rest hours (morning through afternoon), and was high during the activity hours (night). The periodicity of this oscillation persisted and became free-running when the animals were exposed for 6 consecutive days to constant light or darkness. It was thus demonstrated that the fluctuation of c-fos expression is circadian and is not created by the light-dark cycle, but the latter exerts a synchronizing effect. The oscillation of c-fos mRNA was modified by manipulations of the rest-activity cycle. In particular, the fluctuation observed in basal conditions was inverted, keeping the animals awake during the rest hours (diurnal) and allowing them to sleep in the activity period (nocturnal). These data indicated a close relationship between the oscillation of c-fos expression and the rest-activity cycle. Finally, electroencephalographic (EEG) monitoring was performed under behavioural control for 3 h before the animals were killed. These experiments confirmed that, irrespective of the time of day, the EEG pattern typical of a state of sleep (including both slow waves and paradoxical sleep) was associated with low or undetectable c-fos levels, whereas the protracted EEG desynchronization corresponding to wakefulness was associated with high c-fos expression.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Ciclos de Atividade/fisiologia , Encéfalo/metabolismo , Ritmo Circadiano , Proteínas Proto-Oncogênicas c-fos/genética , RNA Mensageiro/metabolismo , Animais , Northern Blotting , Masculino , Fotoperíodo , Ratos , Ratos Wistar , Sono/fisiologia , Distribuição Tecidual , Transcrição Gênica , Vigília/fisiologia
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