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1.
Environ Pollut ; 237: 442-451, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29505984

RESUMO

Glyphosate has been the most widely used herbicide worldwide over the last three decades, raising increasing concerns for its potential impacts on environmental and human health. Recent studies revealed that glyphosate occurs in soil, surface water, and groundwater, and residues are found at all levels of the food chain, such as drinking water, plants, animals, and even in humans. While research has demonstrated that glyphosate can induce a broad range of biological effects in exposed organisms, the global molecular mechanisms of action still need to be elucidated, in particular for marine species. In this study, we characterized for the first time the molecular mechanisms of action of glyphosate in a marine bivalve species after exposure to environmentally realistic concentrations. To reach such a goal, Mediterranean mussels Mytilus galloprovincialis, an ecologically and economically relevant species, were exposed for 21 days to 10, 100, and 1000 µg/L and digestive gland transcriptional profiles were investigated through RNA-seq. Differential expression analysis identified a total of 111, 124, and 211 differentially regulated transcripts at glyphosate concentrations of 10, 100, and 1000 µg/L, respectively. Five genes were found consistently differentially expressed at all investigated concentrations, including SERP2, which plays a role in the protection of unfolded target proteins against degradation, the antiapoptotic protein GIMAP5, and MTMR14, which is involved in macroautophagy. Functional analysis of differentially expressed genes reveals the disruption of several key biological processes, such as energy metabolism and Ca2+ homeostasis, cell signalling, and endoplasmic reticulum stress response. Together, the results obtained suggest that the presence of glyphosate in the marine ecosystem should raise particular concern because of its significant effects even at the lowest concentration.


Assuntos
Glicina/análogos & derivados , Mytilus/fisiologia , Testes de Toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Ecotoxicologia , Proteínas de Ligação ao GTP , Glicina/toxicidade , Herbicidas/metabolismo , Humanos , Mytilus/metabolismo , Transcrição Gênica/efeitos dos fármacos , Poluentes Químicos da Água/metabolismo , Glifosato
2.
Biofabrication ; 9(2): 025012, 2017 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-28393760

RESUMO

Silica-bonded calcite scaffolds have been successfully 3D-printed by direct ink writing, starting from a paste comprising a silicone polymer and calcite powders, calibrated in order to match a SiO2/CaCO3 weight balance of 35/65. The scaffolds, fabricated with two slightly different geometries, were first cross-linked at 350 °C, then fired at 600 °C, in air. The low temperature adopted for the conversion of the polymer into amorphous silica, by thermo-oxidative decomposition, prevented the decomposition of calcite. The obtained silica-bonded calcite scaffolds featured open porosity of about 56%-64% and compressive strength of about 2.9-5.5 MPa, depending on the geometry. Dissolution studies in SBF and preliminary cell culture tests, with bone marrow stromal cells, confirmed the in vitro bioactivity of the scaffolds and their biocompatibility. The seeded cells were found to be alive, well anchored and spread on the samples surface. The new silica-calcite composites are expected to be suitable candidates as tissue-engineering 3D scaffolds for regeneration of cancellous bone defects.


Assuntos
Carbonato de Cálcio/química , Dióxido de Silício/química , Alicerces Teciduais/química , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Células da Medula Óssea/citologia , Técnicas de Cultura de Células , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Força Compressiva , Concentração de Íons de Hidrogênio , Tinta , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Camundongos , Microscopia Eletrônica de Varredura , Microscopia de Fluorescência , Impressão Tridimensional , Propriedades de Superfície
3.
Appl Radiat Isot ; 126: 138-145, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28187932

RESUMO

Characterization and calibration measurements were carried out at the National Institute of Ionizing Radiation Metrology of ENEA on the TAp WAter RAdioactivity (TAWARA) Real Time Monitor system recently developed for real time monitoring of radioactive contamination in water processed at water treatment facilities. Reference radiations and radionuclides were chosen in order to reflect energy ranges and radiation types of the major water radioactive contaminants possibly arising from environmental, industrial or terroristic origin. The following instrument parameters were tested: sensitivity, selectivity, background, short/long term stability, linearity with respect to activity.


Assuntos
Sistemas Computacionais , Monitoramento de Radiação/instrumentação , Poluentes Radioativos da Água/análise , Purificação da Água , Partículas alfa , Partículas beta , Calibragem , Sistemas Computacionais/estatística & dados numéricos , Desenho de Equipamento , Humanos , Monitoramento de Radiação/normas , Monitoramento de Radiação/estatística & dados numéricos , Radioisótopos/análise , Padrões de Referência , Espectrometria gama , Poluentes Radioativos da Água/normas , Contaminação Radioativa da Água/análise , Purificação da Água/normas
4.
Mar Environ Res ; 99: 136-48, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24836120

RESUMO

Anthropogenic emissions of carbon dioxide are leading to decreases in pH and changes in the carbonate chemistry of seawater. Ocean acidification may negatively affect the ability of marine organisms to produce calcareous structures while also influencing their physiological responses and growth. The aim of this study was to evaluate the effects of reduced pH on the survival, growth and shell integrity of juveniles of two marine bivalves from the Northern Adriatic sea: the Mediterranean mussel Mytilus galloprovincialis and the striped venus clam Chamelea gallina. An outdoor flow-through plant was set up and two pH levels (natural seawater pH as a control, pH 7.4 as the treatment) were tested in long-term experiments. Mortality was low throughout the first experiment for both mussels and clams, but a significant increase, which was sensibly higher in clams, was observed at the end of the experiment (6 months). Significant decreases in the live weight (-26%) and, surprisingly, in the shell length (-5%) were observed in treated clams, but not in mussels. In the controls of both species, no shell damage was ever recorded; in the treated mussels and clams, damage proceeded via different modes and to different extents. The severity of shell injuries was maximal in the mussels after just 3 months of exposure to a reduced pH, whereas it progressively increased in clams until the end of the experiment. In shells of both species, the damaged area increased throughout the experiment, peaking at 35% in mussels and 11% in clams. The shell thickness of the treated and control animals significantly decreased after 3 months in clams and after 6 months in mussels. In the second experiment (3 months), only juvenile mussels were exposed to a reduced pH. After 3 months, the mussels at a natural pH level or pH 7.4 did not differ in their survival, shell length or live weight. Conversely, shell damage was clearly visible in the treated mussels from the 1st month onward. Monitoring the chemistry of seawater carbonates always showed aragonite undersaturation at 7.4 pH, whereas calcite undersaturation occurred in only 37% of the measurements. The present study highlighted the contrasting effects of acidification in two bivalve species living in the same region, although not exactly in the same habitat.


Assuntos
Exoesqueleto/efeitos dos fármacos , Bivalves/crescimento & desenvolvimento , Água do Mar/química , Análise de Variância , Exoesqueleto/química , Exoesqueleto/ultraestrutura , Animais , Bivalves/efeitos dos fármacos , Pesos e Medidas Corporais , Dióxido de Carbono/análise , Concentração de Íons de Hidrogênio , Mar Mediterrâneo , Microscopia Eletrônica de Varredura , Mortalidade , Especificidade da Espécie
5.
G Ital Med Lav Ergon ; 33(3 Suppl): 289-92, 2011.
Artigo em Italiano | MEDLINE | ID: mdl-23393859

RESUMO

The study analyzes the variability of respiratory parameters in 59 workers exposed to talc at least 5 years. Cigarettes smoke seems to be the only one variable causing a FEV1 decrease while cumulative exposure doesn't influence any variable analyzed. The talc dust exposure below TLV ACGIH value has not effects on lung function. The function alterations showed are not correlated to task and to cumulative exposure.


Assuntos
Exposição Ocupacional/efeitos adversos , Talco/efeitos adversos , Volume Expiratório Forçado , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Testes de Função Respiratória
6.
G Chir ; 29(10): 427-8, 2008 Oct.
Artigo em Italiano | MEDLINE | ID: mdl-18947468

RESUMO

Association between cervico-thoracic liposarcoma and HIV infection is uncommon. The etiopathology remains unclear and clinical symptoms can be various, often not very evident or absolutely absent. Preoperative diagnosis is based on modern imaging techniques. In selected cases, the ideal procedure is surgical treatment which allows good long-term results. A case of cervico-thoracic liposarcoma in HIV patient is presented.


Assuntos
Vértebras Cervicais , Infecções por HIV/complicações , Hospedeiro Imunocomprometido , Lipossarcoma/complicações , Neoplasias de Tecidos Moles/complicações , Vértebras Torácicas , Idoso , Infecções por HIV/diagnóstico , Infecções por HIV/cirurgia , Humanos , Lipossarcoma/diagnóstico , Lipossarcoma/cirurgia , Masculino , Neoplasias de Tecidos Moles/diagnóstico , Neoplasias de Tecidos Moles/cirurgia , Resultado do Tratamento
7.
G Chir ; 26(5): 224-8, 2005 May.
Artigo em Italiano | MEDLINE | ID: mdl-16184709

RESUMO

The Authors conducted a study on 780 patients who underwent surgery. Fourteen patients developed operative table-induced pressure ulcers of different gravity. This paper is a description of these 14 cases. From the literature and from experience we know that the major exogenous risk factor for intraoperative pressure ulcers is the operation time. Therefore, special attention should be paid to preoperative, intraoperative and postoperative prevention. The knowledge of the pathology, specialized personnel and the use of appropriate facilities can reduce the risks of complication that are important sanitary and economic issue.


Assuntos
Complicações Pós-Operatórias/etiologia , Úlcera por Pressão/etiologia , Procedimentos Cirúrgicos Operatórios/efeitos adversos , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/prevenção & controle , Úlcera por Pressão/prevenção & controle , Fatores de Risco , Fatores Sexuais , Fatores de Tempo
8.
J Chromatogr A ; 1082(1): 43-50, 2005 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-16038193

RESUMO

A new method for simultaneous determination of underivatized biogenic amines based on the separation by cation-exchange chromatography and suppressed conductivity coupled with mass spectrometry detection has been developed. The method has been applied to the analysis of cadaverine, putrescine, histamine, agmatine, phenethylamine and spermidine in processed meat products. The amines were extracted from muscle tissue with methanesulfonic acid without any additional derivative step or sample clean-up. Biogenic amines were separated by the IonPac CS17 column, a cation-exchange column used with gradient elution, and detection was done by suppressed conductivity and mass spectrometry. Tyramine was simultaneously analysed by using a spectrophotometer (275 nm) before the suppressed conductivity detection. Linearity of response was obtained in the range 0.25-25 microg mL(-1). The detection limits ranged from 23 microg L(-1) for putrescine to 155 microg L(-1) for spermidine (suppressed conductivity) and from 9 microg L(-1) for agmatine to 34 microg L(-1) for spermidine (MS). Average recoveries from meat samples ranged from 85 to 97% and coefficients of variation ranged from 4.5 to 9.7%. The analysis of biogenic amines in fresh and processed meats (dry-cured, cooked and fermented products) can be used as a quality marker of raw material and for studying the relationship between their changes and the fermentation process involved in dry sausage ripening.


Assuntos
Aminas Biogênicas/análise , Cromatografia por Troca Iônica/métodos , Espectrometria de Massas/métodos , Produtos da Carne/análise , Carne/análise , Animais , Culinária , Suínos , Raios Ultravioleta
9.
Eur Rev Med Pharmacol Sci ; 9(6): 355-9, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16479740

RESUMO

BACKGROUND: Substernal goiter, also said cervico-mediastinic goiter, is a thyroid formation with cervical departure that goes beyond, with stretched neck, the superior thoracic strait for at least 3 cm and that preserves, generally, the parenchimal or fibrous connections between the cervical and thoracic portion, maintaining a direct vascularization supplied by the thyroid arteries. The prevalence of this pathology is very variable and fluctuates between 1.7% and 30% of all thyroid damages. The actual classification is provided by the radiologic examination of the chest and, above all, by the new techniques of imaging. METHODS: In the period between January 1998 and December 2003, 332 patients with thyroid pathology have been treated surgically. Forthy-five (13.5%) of these were afflicted with a cervico-mediastinic goiter. In 32/45 (71.1%) cases a total thyroidectomy has been performed by collar carving in accordance with Kocher; in 11/45 (24.5%) cases an hemithyroidectomy has been performed by collar incision; in 2/45 (4.4%) cases, already submitted to surgical intervention of isthmus-lobectomy a totalization has been performed. RESULTS: The surgical technique foresees always an anterior collar neck incision. This way of access is to prefer in the substernal goiters, both for the presence of a cervical vascularization easy to control and for the possibility, nearly always realizable, to dislocate the goiter by that way. As for what concerns the results of the histological examination, in 2/45 (4.5%) cases it has been set a diagnosis of follicular carcinoma (one of them surely invading and the other, leastly invading), in 3/45 (6.6%) cases papillary carcinoma, in 4/45 (8.8%) cases colloido-cystic goiter, in 33/45 (73.5%) cases micro-macrofollicular hyperplasia (in one of which contemporarily compromise from lymphoma of Hodgkin); in 3/45 (6.6%) cases of adenomatous hyperplasia of the thyroid. DISCUSSION: The surgical approach has been in all cases the collar neck incision in accordance to Kocher, and it has never been necessary to associate a sternotomy or thoracotomy. After the intervention, in all the patients the symptomatology tied to the mediastinal compression has disappeared. The goiter showed signs of neoplastic degeneration in 11.1% of the cases, with prevalence of the papillary carcinoma in the 6.6% and, in the remaining 4.5%, of follicular carcinoma. These data are superimposable to the data gathered in other surveys. All the patients passed the post-operating hospitalization in optimal conditions and have been discharged during the fourth post-operating day with the prescription of increasing levothyroxine doses according to the body weigh.


Assuntos
Bócio Subesternal/cirurgia , Glândula Tireoide/cirurgia , Adenocarcinoma Folicular/diagnóstico , Adenocarcinoma Folicular/cirurgia , Adulto , Idoso , Carcinoma Papilar/diagnóstico , Carcinoma Papilar/cirurgia , Procedimentos Cirúrgicos Eletivos/métodos , Procedimentos Cirúrgicos Eletivos/normas , Feminino , Bócio Subesternal/diagnóstico , Bócio Subesternal/epidemiologia , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia/métodos , Tireoidectomia/estatística & dados numéricos , Fatores de Tempo
10.
G Chir ; 23(5): 209-11, 2002 May.
Artigo em Italiano | MEDLINE | ID: mdl-12228974

RESUMO

Neurinomas, also referred to as neurilemmomas and schwannomas, are rare benign tumours of the peripheral nerves. A small percentage of these lesions arise from the brachial plexus. The Authors report two cases of schwannoma arising from the brachial plexus. Such lesions, usually asymptomatic, may cause sensitivity alterations or, less frequently, motor deficits in the involved arm. Tumour enucleation, avoiding damage to any of the nervous fascicles, is the treatment of choice.


Assuntos
Neuropatias do Plexo Braquial , Neurilemoma , Neoplasias do Sistema Nervoso Periférico , Neuropatias do Plexo Braquial/diagnóstico , Neuropatias do Plexo Braquial/diagnóstico por imagem , Neuropatias do Plexo Braquial/cirurgia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neurilemoma/diagnóstico , Neurilemoma/diagnóstico por imagem , Neurilemoma/cirurgia , Neoplasias do Sistema Nervoso Periférico/diagnóstico , Neoplasias do Sistema Nervoso Periférico/diagnóstico por imagem , Neoplasias do Sistema Nervoso Periférico/cirurgia , Fatores de Tempo , Ultrassonografia
11.
Rapid Commun Mass Spectrom ; 15(22): 2051-7, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11746868

RESUMO

The composition of a commercial dehydroascorbic acid (DA) solution at pH 2 was investigated by liquid chromatography/mass spectrometry (LC/MS) and liquid chromatography/tandem mass spectrometry (LC/MS/MS) to establish the nature of its different forms and its decomposition products. In freshly prepared solutions, dimeric forms of DA and the hydrated bicyclic hemiketal of DA are the species mainly present in solution. In the presence of light, the initial dimeric species disappears over time to give other dehydrated dimers some of which decompose to the monomer. The comparison of these data with similar data obtained for ascorbic acid (AA) solutions under the same experimental conditions revealed that, in the presence of light, the aging of such AA solutions gives rise to only the hemiketal form of DA, and that no dimeric species of DA were formed. The presence of the hemiketal form of DA was not revealed by analysis of the same AA solutions using the conventional LC/UV technique. The natural form of DA from the oxidation of AA is the hydrated bicyclic form.


Assuntos
Ácido Desidroascórbico/análise , Ácido Ascórbico/análise , Cromatografia Líquida , Ácido Desidroascórbico/química , Dimerização , Espectrometria de Massas , Oxirredução
12.
Anal Chem ; 72(20): 4934-9, 2000 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-11055712

RESUMO

Ascorbic (H2A) and dehydroascorbic (DA) acids were for the first time directly determined in a single chromatographic run by means of the tris(2,2'-bipyridine)ruthenium(II) (Ru(bpy)(3)2+) based electrogenerated chemiluminescence (ECL) detection. For the first time, it was demonstrated that DA, a nonelectroactive compound, is ECL active and is responsible for the ECL behavior of H2A. This fact, together with the lack of a DA standard, suggested the use of a calibration graph obtained for H2A, for determining both analytes. The proven ECL activity of DA, together with literature data relative to the standard redox potentials of the different species coming from H2A, led to a reconsideration of the proposed ECL reaction mechanism for H2A. The role of the OH- ion in the reaction mechanism of the two analytes appeared to be crucial. H2A and DA could be separated by a suitable C18-reversed-phase HPLC column using an aqueous 30 mM H3PO4 solution as the mobile phase. The optimal ECL response was achieved by polarizing the working electrode at 1.150 Vvs SCE (standard calomel electrode) (oxidation diffusion limiting potential for both H2A and Ru(bpy)(3)2+). The Ru(bpy)(3)2+ solution, at pH 10 for carbonate buffer, was mixed to the eluent solution in a postcolumn system, obtaining, still at pH 10, the final 0.25 mM Ru(bpy)(3)2+ concentration. The detection limit found for the two analytes was 1 x 10(-7) M. The method was successfully applied to the determination of the analytes in a commercially available orange fruit juice.

13.
Rapid Commun Mass Spectrom ; 14(6): 373-8, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10717645

RESUMO

This paper describes a simple, effective analytical procedure, based on a gas chromatographic mass spectrometric technique, for the speciation analysis of organotin compounds (OTC) in mussel samples. The direct alkylation reaction of the organotin chlorides in the aqueous digestion solution by NaBEt(4) allowed a short analysis time and a good recovery. The evaluation of the yield of each step constituting the analytical procedure indicated that the alkylation step is the most critical one. The proposed method was advantageously utilised to monitor the level of OTC pollution of the Lagoon of Venice. All the sites examined, both near to and far from anthropogenic activities, revealed significant levels of OTC pollution.


Assuntos
Bivalves/química , Compostos Orgânicos de Estanho/análise , Poluentes Químicos da Água/análise , Animais , Calibragem , Indicadores e Reagentes , Região do Mediterrâneo , Estações do Ano
14.
Analyst ; 125(11): 1955-8, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11193081

RESUMO

A procedure for the extraction of paromomycin from different animal feed matrices (rabbit, chicken, pig feeds) and its subsequent determination via a reversed-phase ion-pair HPLC separation coupled with pulsed amperometric detection is described. The procedure optimised in terms of the extracting solvent and the solid phase extraction stationary phase allows the total recovery of the aminoglycoside antibiotic. The criteria used for the validation of the analytical method applied to the cited matrices are the linear dynamic range of the response, the detection limit, the repeatability, the intermediate repeatability and the accuracy. A comparison with a method described in the literature for the bulk analysis of this antibiotic is made.


Assuntos
Antibacterianos/análise , Paromomicina/análise , Drogas Veterinárias/análise , Ração Animal , Animais , Antibacterianos/química , Galinhas , Cromatografia Líquida de Alta Pressão/métodos , Paromomicina/química , Coelhos , Suínos , Drogas Veterinárias/química
15.
Radiol Med ; 95(6): 624-9, 1998 Jun.
Artigo em Italiano | MEDLINE | ID: mdl-9717546

RESUMO

INTRODUCTION: Radiofrequency hyperthermia using the newly-developed "cooled-tip" needle is one of the latest US-guided percutaneous treatments of hepatocellular carcinoma arising in cirrhosis. The continuous cooling of the needle tip allows tissue heating and necrosis far from the electrode without tissue charring, which was the major drawback of the old monopolar technique. Herein we report our preliminary results on feasibility and effectiveness of the thermoablation of mono- or paucifocal hepatocellular carcinoma with the cooled-tip needle. MATERIAL AND METHODS: November, 1996, to January, 1998, we treated thirteen cirrhotic patients (mean age 69.5 yrs, 10 men, 12 HCV-positive; 11 in Child's Class A and 2 in Class B) with 19 hepatocellular carcinoma nodules (mean diameter: 27 mm; range: 10-41 mm; 6 with diameter > 3 cm). None of the patients had portal thrombosis and/or extrahepatic spread. We used a radiofrequency generator (100 W power) connected to an 18 G perfusion electrode needle with an exposed tip of 2-3 cm. The circuit is closed through a dispersive electrode positioned under the patient's thighs. A peristaltic pump infuses a chilled (2-5 degrees C) saline solution to guarantee the continuous cooling of the needle tip. The needle was placed into target lesions under US guidance. The interventional procedure was carried out under general anesthesia using Propofol without intubation. Dynamic CT (more recently with the helical technique) was carried out 15-20 days after thermoablation to assess treatment efficacy. RESULTS: In all, 31 thermal injuries (at 1000-1200 mA for 10-15 minutes) were caused in 21 sessions in the 19 hepatocellular carcinoma nodules (mean: 1.5 lesions per nodule and 1.6 sessions per patient). Complete necrosis as assessed at dynamic CT (no enhancement during the arteriographic phase) was achieved in 16 of 19 nodules (84%). No side-effects occurred. During the follow-up (median: 11 months) no death occurred and five patients had recurrent hepatocellular carcinoma appearing either as single nodule or as multinodular liver involvement. CONCLUSIONS: In our experience radiofrequency hyperthermia with the cooled-tip needle permits effective and safe percutaneous ablation of HCC in cirrhosis. In addition, treatment time is short and lesions > 3 cm can be treated. Further experience is needed to better define the role of percutaneous thermoablation in the treatment strategy of hepatocellular carcinoma.


Assuntos
Carcinoma Hepatocelular/cirurgia , Ablação por Cateter/métodos , Cirrose Hepática/cirurgia , Neoplasias Hepáticas/cirurgia , Ultrassonografia de Intervenção/métodos , Idoso , Carcinoma Hepatocelular/diagnóstico por imagem , Ablação por Cateter/instrumentação , Feminino , Seguimentos , Humanos , Fígado/diagnóstico por imagem , Fígado/cirurgia , Cirrose Hepática/complicações , Cirrose Hepática/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Agulhas , Recidiva Local de Neoplasia/epidemiologia , Tomografia Computadorizada por Raios X
16.
Mutat Res ; 413(1): 1-6, 1998 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-9602852

RESUMO

Six halogenated anaesthetics were tested for their ability to induce micronuclei formation in the rat kidney. A statistically significant increase in the frequency of micronucleated cells was detected in rats given a single p.o. dose of 4 mmol/kg of halothane (3.48 x baseline), chloroform (3.32 x baseline), trichloroethylene (3.24 x baseline), sevoflurane (2.98 x baseline), and isoflurane (2.95 x baseline). In contrast, the response was substantially negative in rats given the same dose of enflurane. As compared to controls, rats treated with halothane and trichloroethylene displayed a reduction in the frequency of binucleated cells presumably due to a toxicity-induced inhibition of cellular proliferation. These findings suggest a potential genotoxic activity of halogenated anaesthetics for the rat kidney.


Assuntos
Anestésicos Inalatórios/toxicidade , Rim/efeitos dos fármacos , Micronúcleos com Defeito Cromossômico , Mutagênicos/toxicidade , Animais , Clorofórmio/toxicidade , Halotano/toxicidade , Isoflurano/toxicidade , Rim/ultraestrutura , Masculino , Éteres Metílicos/toxicidade , Ratos , Ratos Sprague-Dawley , Sevoflurano , Tricloroetileno/toxicidade
17.
Mutat Res ; 390(1-2): 51-7, 1997 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-9150752

RESUMO

A micronucleus assay in vivo has been developed that is based on the use of freshly isolated kidney cells from mononephrectomized rats. In this validation study, a statistically significant increase in the frequency of micronucleated cells was detected in rats given i.p. a single dose of four kidney carcinogens, N-nitrosodimethylamine, N-nitrosodiethylamine, N-ethyl-N-hydroxyethylnitrosamine and N-nitroso-N-methylurea. The clastogenic effect was more marked when the same dose was injected for 3 successive days. As compared to controls, treated rats displayed a reduction in the frequency of binucleated cells, presumably due to a toxicity-induced inhibition of cellular proliferation. The proposed method should be suitable for the detection of the clastogenic effect of procarcinogens biotransformed into reactive species in the kidney.


Assuntos
Rim/efeitos dos fármacos , Testes para Micronúcleos , Mutagênicos/toxicidade , Animais , Células Cultivadas , Dietilnitrosamina/análogos & derivados , Dietilnitrosamina/toxicidade , Dimetilnitrosamina/toxicidade , Relação Dose-Resposta a Droga , Rim/citologia , Masculino , Metilnitrosoureia/toxicidade , Ratos , Ratos Sprague-Dawley
18.
Eur Rev Med Pharmacol Sci ; 1(5): 139-42, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9630754

RESUMO

The authors report a case of cecal malignant carcinoid, diagnosticated in a 68 years old male patient. Carcinoid tumours are rare neoplasm and their behaviour seems to change with the localization. Cecal carcinoid represents only 2-3% of gastrointestinal carcinoid. Some times it is discovered incidentally at autopsy, surgery or endoscopy. The aim of this paper has been to review, in literature, the frequency, treatment and prognosis of this neoplasm.


Assuntos
Neoplasias do Ceco/patologia , Síndrome do Carcinoide Maligno/patologia , Idoso , Neoplasias do Ceco/cirurgia , Humanos , Masculino , Síndrome do Carcinoide Maligno/cirurgia
19.
Eur J Ultrasound ; 6(3): 185-189, 1997 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-9795051

RESUMO

A case of neoplastic implant after percutaneous ethanol injection (PEI) therapy for hepatocellular carcinoma (HCC) occurring in two steps is described. A 74-year-old male cirrhotic patient underwent PEI for a 5-cm HCC nodule. To obtain complete tumoral necrosis, 80 ml were injected under sonographic guidance in four sessions. Ten months after the completion of PEI a subcutaneous nodule was palpated in the abdominal wall within the area of needle punctures. Histologic examination of the excised nodule confirmed the sonographic and Power Doppler diagnosis of metastatic HCC. At the US exam scheduled three months later a non-palpable subcutaneous nodule of 16 mm was appreciated near the surgical wound. Once again metastatic HCC was demonstrated at pathological examination. Copyright 1997 Elsevier Science Ireland Ltd.

20.
J Neurosci ; 14(10): 6084-93, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7931564

RESUMO

Synaptic release of dopamine in the nucleus accumbens of the intact rat brain elicited by a single electrical impulse applied to ascending dopaminergic fibers results in extracellular concentrations sufficient to bind the known dopamine receptors. The dopamine concentration observed after four rapid, sequential pulses is exactly four times greater and is unaffected by pharmacological antagonism of dopamine uptake and receptor sites at supramaximal concentrations. Thus, dopamine efflux from the synaptic cleft is not restricted by binding to intrasynaptic proteins on the time scale of the measurements (50-100 msec). The extracellular concentration, as a result of a single stimulus pulse, is 0.25 microM and is rapidly removed by extrasynaptic uptake. This maximal, transient concentration of dopamine is 60 times higher than steady-state concentrations reported previously using dialysis techniques, illustrating that dopamine extracellular concentrations are spatially and temporally heterogenous. In contrast to ACh transmission at the neuromuscular junction, the dopamine synapse in the telencephalon is designed for the effective efflux of dopamine from the synaptic cleft to the extrasynaptic compartment during neurotransmission.


Assuntos
Dopamina/metabolismo , Núcleo Accumbens/metabolismo , Sinapses/metabolismo , Animais , Dopamina/análise , Dopamina/fisiologia , Estimulação Elétrica , Espaço Extracelular/química , Espaço Extracelular/fisiologia , Masculino , Nomifensina/farmacologia , Núcleo Accumbens/química , Núcleo Accumbens/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Receptores Dopaminérgicos/análise , Sulpirida/farmacologia , Sinapses/efeitos dos fármacos
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