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1.
Int Health ; 12(2): 116-124, 2020 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-31294781

RESUMO

BACKGROUND: Travellers' risk perception is a key component of travel risk assessment because it influences the adequate implementation of safety precautions. The aims of this study are to validate a tool to analyse travellers' risk perception to identify which factors can influence it and how it changes upon return. METHODS: The Traveller's Risk Perception (TRiP) questionnaire was developed and administered to outpatients before and after travel in three travel clinics. A principal component analysis (PCA) was performed to validate the questionnaire and multivariate regression analysis was used to evaluate the effect of travellers' characteristics on the risk scores. RESULTS: A total of 1020 travellers completed the questionnaire. PCA identified two latent factors: 'generic-disseminated risks' and 'specific-circumstantial risks'. Cronbach's α was acceptable (0.76 and 0.70, respectively). The 'generic-disseminated risks' dimension scored higher than the 'specific-circumstantial risks' (p<0.001). The items with the highest scores were insect bites, gastrointestinal disorders and malaria. The mean scores were significantly lower after the travel for all items but one. CONCLUSIONS: The TRiP questionnaire is a valid and reliable tool for rating travellers' perceptions. Staff in travel clinics should be trained to systematically assess travellers' risk perception in order to tailor the consultation according to specific information needs.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Inquéritos e Questionários , Viagem , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Medição de Risco , Adulto Jovem
5.
Gene ; 589(2): 127-32, 2016 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-26143115

RESUMO

A "cancer predisposing syndrome" later labeled as Hereditary Non-Polyposis Colorectal Cancer (HNPCC) or Lynch Syndrome, was firstly described by Warthin, about one century ago. An increased predisposition to the development of multiple familial tumors is described as characteristic of this syndrome where visceral and cutaneous malignancies may appear at an early age namely endometrial, gastric, small bowel, ureteral and renal pelvis, ovarian, hepatobiliary tract, pancreatic, brain (Turcot Syndrome) and sebaceous glands (Muir-Torre Syndrome). The latter, a variant of Lynch Syndrome, is characterized by the presence of sebaceous skin adenomas, carcinomas and/or keratoacanthomas associated with visceral malignancies. Both Lynch Syndrome and Muir-Torre Syndrome have been recognized due to germline mutations in mismatch repair genes MLH1, MSH2 and MSH6. To date, 56 Lynch Syndrome founder mutations dependent on MLH1, MSH2 and, although less frequently found, MSH6 and PMS2 are described. Some of these founder mutations, principally of MSH2 gene, have been described to cause Muir-Torre phenotype and have been traced in large and outbreed Muir-Torre Syndrome families living in different US and European territories. Due to the evidences of highly specific Muir-Torre phenotypes related to the presence of widespread MSH2 founder mutations, preliminary search for these MSH2 common mutations in individuals carrying sebaceous tumors and/or keratoacanthomas, at early age or in association to visceral and familial tumors, permits cost-effective and time-saving diagnostic strategies for Lynch/Muir-Torre Syndromes.


Assuntos
Neoplasias Encefálicas/história , Neoplasias Colorretais Hereditárias sem Polipose/história , Neoplasias Colorretais/história , Proteínas de Ligação a DNA/genética , Síndrome de Muir-Torre/história , Proteína 1 Homóloga a MutL/genética , Proteína 2 Homóloga a MutS/genética , Síndromes Neoplásicas Hereditárias/história , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Colo/metabolismo , Colo/patologia , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Neoplasias Colorretais Hereditárias sem Polipose/diagnóstico , Neoplasias Colorretais Hereditárias sem Polipose/genética , Neoplasias Colorretais Hereditárias sem Polipose/patologia , Feminino , Efeito Fundador , Expressão Gênica , Mutação em Linhagem Germinativa , História do Século XX , História do Século XXI , Humanos , Masculino , Endonuclease PMS2 de Reparo de Erro de Pareamento/genética , Síndrome de Muir-Torre/diagnóstico , Síndrome de Muir-Torre/genética , Síndrome de Muir-Torre/patologia , Síndromes Neoplásicas Hereditárias/diagnóstico , Síndromes Neoplásicas Hereditárias/genética , Síndromes Neoplásicas Hereditárias/patologia , Linhagem , Glândulas Sebáceas/metabolismo , Glândulas Sebáceas/patologia
7.
Clin Genet ; 87(6): 507-16, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25345868

RESUMO

Founder mutations in specific populations are common in several Mendelian disorders. They are shared by apparently unrelated families that inherited them from a common ancestor that existed hundreds to thousands of years ago. They have been proven to impact in molecular diagnostics strategies in specific populations, where they can be assessed as the first screening step and, if positive, avoid further expensive gene scanning. In Lynch syndrome (LS), a dominantly inherited colorectal cancer disease, more than 50 founder pathogenic mutations have been described so far in the mismatch repair (MMR) genes (MLH1, MSH2, MSH6 and PMS2). We here provide a comprehensive summary of the founder mutations found in the MMR genes and an overview of their main characteristics. At a time when high-throughput strategies are being introduced in the molecular diagnostics of cancer, genetic testing for founder mutations can complement next generation sequencing (NGS) technologies to most efficiently identify MMR gene mutations in any given population. Additionally, special attention is paid to MMR founder mutations with interesting anthropological significance.


Assuntos
Neoplasias Colorretais Hereditárias sem Polipose/genética , Reparo de Erro de Pareamento de DNA/genética , Efeito Fundador , Mutação , Proteínas Adaptadoras de Transdução de Sinal/genética , Antígenos de Neoplasias/genética , Moléculas de Adesão Celular/genética , Neoplasias Colorretais Hereditárias sem Polipose/diagnóstico , Neoplasias Colorretais Hereditárias sem Polipose/epidemiologia , Gerenciamento Clínico , Epigênese Genética , Molécula de Adesão da Célula Epitelial , Genética Populacional , Mutação em Linhagem Germinativa , Humanos , Judeus/genética , Proteína 1 Homóloga a MutL , Proteína 2 Homóloga a MutS/genética , Proteínas Nucleares/genética , Vigilância da População , Prognóstico
8.
J Biomater Appl ; 29(10): 1363-71, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25542733

RESUMO

The uremic syndrome is attributed to the progressive retention of a large number of toxins, which under normal conditions are excreted by the healthy kidneys. Standard dialytic membranes do not purify middle-high molecular weight toxins. Haemodiafiltration with endogenous reinfusion coupled with a highly permeable membrane could break the limit of the 'albumin wall' improving the dialytic depuration without loss of important nutrients. The aim of this study was to evaluate the performance of a new polysulfone membrane, Synclear 0.2, to remove uremic molecules. Surface Enhanced Laser Desorption Ionization-Time of Flight was employed to evaluate the proteomic profile of ultrafiltrate and Electrospray Ionization-Quadruple-ToF coupled with on-chip elution was used for proteins identification. A high and specific permeability for middle-high molecular weight molecules was revealed by mass spectrometry for the investigated membrane. The identified proteins are mostly uremic toxins: their relative abundance, estimated in the ultrafiltrate by exponentially modified protein abundance index, showed a high purification efficiency of the new membrane when compared with conventional ones. In conclusion, Synclear 0.2, used as convective membrane in hemodiafiltration with endogenous reinfusion treatment, permits to break the 'albumin wall', clearing middle-high molecular weight uremic toxins, improving the dialytic treatment purification efficiency.


Assuntos
Materiais Biocompatíveis , Polímeros , Diálise Renal/métodos , Sulfonas , Toxinas Biológicas/isolamento & purificação , Idoso , Idoso de 80 Anos ou mais , Feminino , Hemodiafiltração/métodos , Humanos , Masculino , Teste de Materiais , Membranas Artificiais , Pessoa de Meia-Idade , Permeabilidade , Proteômica , Albumina Sérica/isolamento & purificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Toxinas Biológicas/sangue , Uremia/sangue , Uremia/terapia
9.
Fam Cancer ; 13(4): 553-61, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24969397

RESUMO

Primary and secondary immunodepressive conditions are associated with an increased incidence of sebaceous tumors. Microsatellite instability (MSI) and lack of expression of mismatch repair (MMR) proteins, typical markers of Muir-Torre/Lynch heredo-familial settings, can be recognized also in immunocompromised patients. We aimed to carry on a systematic examination of clinical, immunohistochemical, biomolecular features of sebaceous tumors arising in immunocompromised and immunocompetent patients between 1986 and 2012. Microsatellite screening, immunohistochemical analysis and genetic testing were performed for hMLH1, hMSH2 and hMSH6. Methylation status of MMR genes was checked in cases with immunohistochemistry (IHC) loss of MMR proteins expression and no germline mutations. Fifteen patients had a personal history of visceral carcinomas fulfilling diagnostic criteria for Muir-Torre syndrome. In this cohort, IHC analysis, MSI status and genetic testing were in agreement, showing eight MSH2 and two MLH1 germline mutations. Five patients were immunosuppressed and their sebaceous tumors showed a lack of MSH2/MSH6 expression, although just one case with positive family history for visceral cancer harbored a germline mutation. In immunosuppressed patients, loss of IHC for MMR proteins is not necessarily secondary to MMR germline mutations. IHC false positives are probably due to epigenetic alterations. MSI and lack of expression of MMR proteins can be recognized also in immunocompromised patients without MMR germline mutations.


Assuntos
Hospedeiro Imunocomprometido/genética , Síndrome de Muir-Torre/genética , Neoplasias das Glândulas Sebáceas/genética , Neoplasias das Glândulas Sebáceas/imunologia , Proteínas Adaptadoras de Transdução de Sinal/biossíntese , Adulto , Idoso , Idoso de 80 Anos ou mais , Metilação de DNA , Análise Mutacional de DNA , Proteínas de Ligação a DNA/biossíntese , Feminino , Humanos , Hospedeiro Imunocomprometido/imunologia , Imuno-Histoquímica , Masculino , Instabilidade de Microssatélites , Pessoa de Meia-Idade , Proteína 1 Homóloga a MutL , Proteína 2 Homóloga a MutS/biossíntese , Proteínas Nucleares/biossíntese , Linhagem
10.
Clin Genet ; 84(1): 65-9, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23061468

RESUMO

Trichilemmal cysts (TCs) can occur as sporadic lesions or in hereditary-familial settings with autosomal dominant transmission. These entities have not been widely analyzed in their peculiar aspects yet. The aim of this study was to describe a cohort of patients with diagnosis of TCs through a clinical and biomolecular characterization, intended to highlight some effective diagnostic criteria for their identification. Among 149 cases of this study, 24 cases of TCs (16.1%) arose in patients with at least one first-degree relative with diagnosis of TCs. Peculiar findings concerning hereditary lesions included the multiple presentation with an early onset age. On the basis of clinical evaluation, we propose a panel of clinical and histologic criteria for the diagnosis of hereditary TCs, which includes: (i) the diagnosis of TCs in at least two first-degree relatives or in three first- or second-degree relatives in two consecutive generations; (ii) at least one of the patients with TCs diagnosed <45 years; and (iii) the diagnosis of multiple or giant (>5-cm lesions) or rare histopathologic features (proliferating and ossifying) TCs.


Assuntos
Cisto Folicular/diagnóstico , Cisto Folicular/genética , Doenças do Cabelo/diagnóstico , Doenças do Cabelo/genética , Receptores de Superfície Celular/genética , Adulto , Idoso , Sequência de Bases , Cisto Epidérmico , Éxons , Feminino , Cisto Folicular/patologia , Cisto Folicular/cirurgia , Doenças do Cabelo/patologia , Doenças do Cabelo/cirurgia , Humanos , Padrões de Herança , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Mutação , Receptores Patched , Linhagem
11.
J Prev Med Hyg ; 53(4): 199-203, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23469588

RESUMO

INTRODUCTION: Estimate the efficacy of oral anticholeric vaccine Dukoral in subjects travelling to high-risk areas for traveler's diarrhoea and cholera. METHODS: The study involved subjects of both genders who planned to travel to high-risk areas for traveler's diarrhoea and cholera. Immunization with oral anticholeric vaccine Dukoral was offered to each one of them. Upon returning, all the participants in the study were asked to complete a self-administered questionnaire consisting of 40 close-ended questions mainly concerning: personal and health data, characteristics (length, destination, reason) of the travel, onset of gastrointestinal symptoms, data relating to the assumption of anticholeric vaccine and possible adverse reactions. RESULTS: 296 questionnaires have been collected. Mean age was 38.2 years (55.4% males and 44.6% females). Mean travel length was 22.2 days. Reasons for the travel: 66.8% tourism and 33.2% work-cooperation. Most frequent destination was Africa (48.1%), followed by Asia (32.1%) and central South-America (17.8%). 199 subjects (67.2%) properly executed vaccination with Dukoral. The diarrhoea affected 14.1% of vaccinated subjects and 20.6% of non vaccinated ones. The following cohorts showed statistically significant differences in incidence of diarrhoea: <35 years old age (13.7% vs. 27.1%), travel for work-cooperation (14.1% vs. 35%) and travel length >28 days (12.1% vs. 40%). No serious adverse events were reported following vaccination. DISCUSSION: Oral Anticholeric vaccine proved to be effective and safe in preventing fecal-oral diseases in travelers exposed to high risk conditions.


Assuntos
Vacinas contra Cólera/administração & dosagem , Cólera/prevenção & controle , Diarreia/prevenção & controle , Infecções por Escherichia coli/prevenção & controle , Viagem/estatística & dados numéricos , Administração Oral , Adulto , Cólera/imunologia , Cólera/transmissão , Diarreia/imunologia , Diarreia/microbiologia , Doenças Endêmicas/prevenção & controle , Escherichia coli Enterotoxigênica/imunologia , Infecções por Escherichia coli/imunologia , Infecções por Escherichia coli/transmissão , Fezes/microbiologia , Feminino , Microbiologia de Alimentos , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Vibrio cholerae/imunologia , Microbiologia da Água
12.
Br J Pharmacol ; 150(5): 595-603, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17245369

RESUMO

BACKGROUND AND PURPOSE: In circulatory shock, melanocortins have life-saving effects likely to be mediated by MC4 receptors. To gain direct insight into the role of melanocortin MC4 receptors in haemorrhagic shock, we investigated the effects of two novel selective MC4 receptor agonists. EXPERIMENTAL APPROACH: Severe haemorrhagic shock was produced in rats under general anaesthesia. Rats were then treated with either the non-selective agonist [Nle4, D-Phe7]-melanocyte-stimulating hormone (NDP--MSH) or with the selective MC4 agonists RO27-3225 and PG-931. Cardiovascular and respiratory functions were continuously monitored for 2 h; survival rate was recorded up to 24 h. Free radicals in blood were measured using electron spin resonance spectrometry; tissue damage was evaluated histologically 25 min or 24 h after treatment. KEY RESULTS: All shocked rats treated with saline died within 30-35 min. Treatment with NDP--MSH, RO27-3225 and PG-931 produced a dose-dependent (13-108 nmol kg-1 i.v.) restoration of cardiovascular and respiratory functions, and improved survival. The three melanocortin agonists also markedly reduced circulating free radicals relative to saline-treated shocked rats. All these effects were prevented by i.p. pretreatment with the selective MC4 receptor antagonist HS024. Moreover, treatment with RO27-3225 prevented morphological and immunocytochemical changes in heart, lung, liver, and kidney, at both early (25 min) and late (24 h) intervals. CONCLUSIONS AND IMPLICATIONS: Stimulation of MC4 receptors reversed haemorrhagic shock, reduced multiple organ damage and improved survival. Our findings suggest that selective MC4 receptor agonists could have a protective role against multiple organ failure following circulatory shock.


Assuntos
Insuficiência de Múltiplos Órgãos/prevenção & controle , Peptídeos Cíclicos/farmacologia , Receptor Tipo 4 de Melanocortina/agonistas , Choque Hemorrágico/tratamento farmacológico , alfa-MSH/análogos & derivados , Animais , Pressão Sanguínea/efeitos dos fármacos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Radicais Livres/sangue , Frequência Cardíaca/efeitos dos fármacos , Rim/efeitos dos fármacos , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Pulmão/efeitos dos fármacos , Pulmão/patologia , Insuficiência de Múltiplos Órgãos/metabolismo , Insuficiência de Múltiplos Órgãos/patologia , Insuficiência de Múltiplos Órgãos/fisiopatologia , Miocárdio/patologia , Peptídeos Cíclicos/uso terapêutico , Ratos , Ratos Wistar , Receptor Tipo 4 de Melanocortina/metabolismo , Mecânica Respiratória , Índice de Gravidade de Doença , Choque Hemorrágico/metabolismo , Choque Hemorrágico/patologia , Choque Hemorrágico/fisiopatologia , Fatores de Tempo , alfa-MSH/farmacologia , alfa-MSH/uso terapêutico
13.
Nitric Oxide ; 5(4): 349-60, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11485373

RESUMO

This in vivo study evaluates the effect of N-acetylcysteine (NAC) administration on nitric oxide (NO) production by the inducible form of nitric oxide synthase (iNOS). NO production was induced in the rat by the ip administration of 2 mg/100 g lipopolysaccharide (LPS). This treatment caused: (1) a decrease in body temperature within 90 min, followed by a slow return to normal levels; (2) an increase in plasma levels of urea, nitrite/nitrate, and citrulline; (3) the appearance in blood of nitrosyl-hemoglobin (NO-Hb) and in liver of dinitrosyl-iron-dithiolate complexes (DNIC); and (4) increased expression of iNOS mRNA in peripheral blood mononuclear cells (PBMC). Rat treatment with 15 mg/100 g NAC ip, 30 min before LPS, resulted in a significant decrease in blood NO-Hb levels, plasma nitrite/nitrate and citrulline concentrations, and liver DNIC complexes. PBMC also showed a decreased expression of iNOS mRNA. NAC pretreatment did not modify the increased levels of plasma urea or the hypothermic effect induced by the endotoxin. The administration of NAC following LPS intoxication (15 min prior to sacrifice) did not affect NO-Hb levels. These results demonstrate that NAC administration can modulate the massive NO production induced by LPS. This can be attributed mostly to the inhibitory effect of NAC on one of the events leading to iNOS protein expression. This hypothesis is also supported by the lack of effect of late NAC administration.


Assuntos
Acetilcisteína/farmacologia , Hemoglobinas/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico/antagonistas & inibidores , Acetilcisteína/metabolismo , Animais , Citrulina/sangue , Espectroscopia de Ressonância de Spin Eletrônica , Hemoglobinas/metabolismo , Proteínas Ferro-Enxofre/efeitos dos fármacos , Proteínas Ferro-Enxofre/metabolismo , Masculino , Modelos Animais , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo II , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ureia/sangue
14.
J Pharmacol Exp Ther ; 297(3): 1082-7, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11356932

RESUMO

The influence of the melanocortin peptide ACTH-(1-24) (adrenocorticotropin) on the consequences of short-term coronary ischemia (5 min) followed by reperfusion, and the effect of the long-acting melanocortin [Nle(4),D-Phe(7)]alpha-melanocyte-stimulating hormone (NDP-MSH) on the damage induced by a permanent coronary occlusion, were investigated in anesthetized rats. Ischemia was produced by ligature of the left anterior descending coronary artery. Reperfusion-induced arrhythmias [ventricular tachycardia (VT), ventricular fibrillation (VF)] and survival rate within the 5 min following reperfusion, blood levels of free radicals detected 2 min after reperfusion by electron spin resonance spectrometry, and amount of healthy myocardial tissue, measured 72 h after permanent coronary occlusion on immunohistologically stained serial sections, were evaluated. Postischemic reperfusion induced VT in all saline-treated rats, and VF and death in a high percentage of animals (87%). In rats treated i.v. (2.5 min after coronary occlusion) with ACTH-(1-24) (0.16-0.48 mg/kg) there was a significantly dose-dependent reduction in the incidence of arrhythmias and lethality. Ischemia/reperfusion caused a large increase in free radical blood levels; treatment with ACTH-(1-24) (0.48 mg/kg i.v.) almost completely prevented this increase. In rats subjected to permanent coronary occlusion, the amount of healthy myocardial tissue was much reduced in saline-treated rats, while in rats treated s.c. with NDP-MSH (0.27 mg/kg every 12 h) it was significantly higher. The present data demonstrate, for the first time, an unforeseen property of melanocortin peptides, i.e., their ability to significantly reduce both heart ischemia/reperfusion injury and size of the ischemic area induced by permanent coronary occlusion.


Assuntos
Doença das Coronárias/tratamento farmacológico , Cosintropina/administração & dosagem , Isquemia Miocárdica/tratamento farmacológico , Neuropeptídeos/administração & dosagem , alfa-MSH/administração & dosagem , Animais , Arritmias Cardíacas/prevenção & controle , Doença das Coronárias/metabolismo , Relação Dose-Resposta a Droga , Esquema de Medicação , Eletrocardiografia/efeitos dos fármacos , Espectroscopia de Ressonância de Spin Eletrônica , Feminino , Radicais Livres/antagonistas & inibidores , Radicais Livres/sangue , Injeções Intravenosas , Injeções Subcutâneas , Masculino , Isquemia Miocárdica/metabolismo , Isquemia Miocárdica/patologia , Reperfusão Miocárdica , Ratos , Ratos Wistar , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/prevenção & controle , Taxa de Sobrevida , alfa-MSH/análogos & derivados
15.
Free Radic Res ; 33(3): 329-40, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10993487

RESUMO

It has been claimed that coenzyme Q10 (Q10) would be an effective plasma antioxidant since it can regenerate plasma vitamin E. To test separate effects and interaction between Q10 and vitamin E in the change of plasma concentrations and in the antioxidative efficiency, we carried out a double-masked, double-blind clinical trial in 40 subjects with mild hypercholesterolemia undergoing statin treatment. Subjects were randomly allocated to parallel groups to receive either Q10 (200 mg daily), d-alpha-tocopherol (700 mg daily), both antioxidants or placebo for 3 months. In addition we investigated the pharmacokinetics of Q10 in a separate one-week substudy. In the group that received both antioxidants, the increase in plasma Q10 concentration was attenuated. Only vitamin E supplementation increased significantly the oxidation resistance of isolated LDL. Simultaneous Q10 supplementation did not increase this antioxidative effect of vitamin E. Q10 supplementation increased and vitamin E decreased significantly the proportion of ubiquinol of total Q10, an indication of plasma redox status in vivo. The supplementations used did not affect the redox status of plasma ascorbic acid. In conclusion, only vitamin E has antioxidative efficiency at high radical flux ex vivo. Attenuation of the proportion of plasma ubiquinol of total Q10 in the vitamin E group may represent in vivo evidence of the Q10-based regeneration of the tocopheryl radicals. In addition, Q10 might attenuate plasma lipid peroxidation in vivo, since there was an increased proportion of plasma ubiquinol of total Q10.


Assuntos
Antioxidantes/administração & dosagem , Hipercolesterolemia/tratamento farmacológico , Ubiquinona/administração & dosagem , Vitamina E/administração & dosagem , Idoso , Ácido Ascórbico/sangue , Coenzimas , Suplementos Nutricionais , Método Duplo-Cego , Interações Medicamentosas , Feminino , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Lipoproteínas LDL/sangue , Masculino , Pessoa de Meia-Idade , Placebos , Ubiquinona/análogos & derivados , Ubiquinona/farmacocinética , Ubiquinona/uso terapêutico , Ácido Úrico/sangue , Vitamina E/uso terapêutico
16.
Pathologica ; 92(2): 82-5, 2000 Apr.
Artigo em Italiano | MEDLINE | ID: mdl-10838873

RESUMO

Among the histological variants of meningiomas the oncocytic subtype is rarely observed. Up-today, only six cases of oncocytic meningioma are described. This subtype of meningiomas shows an aggressive behavior and recurrences are more frequent. We describe a case of oncocytic meningioma in a 78-years-old woman. The patient had a history of breast cancer diagnosed 9 years before the brain biopsy; bilateral mastectomy and adjuvant chemotherapy was performed. She had a right frontal tumour measuring 3 cm in diameter. The patient is alive and well eleven months after surgery. The tumour was composed by large polygonal neoplastic cells with finely granular eosinophilic cytoplasm. Neoplastic cells were arranged in sheets and nests delimited by thin fibrous septa rich in vessels. Psammomatous bodies were also present. Mitoses were rare and necrosis was absent. Oncocytic differentiation was demonstrated by conventional histology and immunohistochemistry. Immunohistochemistry revealed a strong and diffuse positivity for antimitochondrial antiserum, vimentin and EMA; a focal reactivity for cytokeratin was observed. The rarity of oncocytic meningiomas is underlined with only six cases described in the world literature. The immunophenotypic profile and the differential diagnosis of the neoplasm is discussed and the concept of oncocytic meningioma as a distinct entity of tumour is emphasized.


Assuntos
Adenoma Oxífilo/patologia , Neoplasias Meníngeas/patologia , Meningioma/patologia , Adenoma Oxífilo/complicações , Adenoma Oxífilo/diagnóstico , Idoso , Biomarcadores Tumorais/análise , Edema Encefálico/etiologia , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/secundário , Neoplasias da Mama , Carcinoma Ductal de Mama/diagnóstico , Carcinoma Ductal de Mama/secundário , Carcinoma Medular , Diagnóstico Diferencial , Feminino , Humanos , Neoplasias Meníngeas/complicações , Neoplasias Meníngeas/diagnóstico , Meningioma/complicações , Meningioma/diagnóstico , Segunda Neoplasia Primária
17.
Artif Organs ; 24(1): 1-6, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10677150

RESUMO

Oxidative stress is crucial in red blood cell (RBC) damage induced by activated neutrophils in in vitro experiments. The aim of the study was to evaluate whether the bioincompatibility phenomena occurring during hemodialysis (HD) (where neutrophil activation with increased free radical production is well documented) may have detrimental effects on RBC. We evaluated RBC susceptibility to oxidative stress before and after HD in 15 patients using Cuprophan, cellulose triacetate, and polysulfone membrane. RBC were incubated with t-butyl hydroperoxide as an oxidizing agent both in the presence and in the absence of the catalase inhibitor sodium azide. The level of malonaldehyde (MDA), a product of lipid peroxidation, was measured at 0, 5, 10, 15, and 30 min of incubation. When Cuprophan membrane was used, the MDA production was significantly higher after HD, indicating an increased susceptibility to oxidative stress in comparison to pre-HD. The addition of sodium azide enhanced this phenomenon. Both cellulose triacetate and polysulfone membranes did not significantly influence RBC susceptibility to oxidative stress. Neither the level of RBC reduced glutathione nor the RBC glutathione redox ratio changed significantly during HD with any of the membranes used. The RBC susceptibility to oxidative stress was influenced in different ways according to the dialysis membrane used, being increased only when using the more bioincompatible membrane Cuprophan, where neutrophil activation with increased free radical production is well documented. The alterations found in this study might contribute to the reduced RBC longevity of HD patients where a bioincompatible membrane is used.


Assuntos
Eritrócitos/metabolismo , Membranas Artificiais , Estresse Oxidativo/fisiologia , Diálise Renal/instrumentação , Materiais Biocompatíveis/química , Catalase/antagonistas & inibidores , Células Cultivadas , Celulose/análogos & derivados , Celulose/química , Inibidores Enzimáticos/farmacologia , Feminino , Radicais Livres/metabolismo , Glutationa/metabolismo , Humanos , Peroxidação de Lipídeos/fisiologia , Masculino , Malondialdeído/metabolismo , Pessoa de Meia-Idade , Ativação de Neutrófilo/fisiologia , Oxidantes/farmacologia , Polímeros/química , Azida Sódica/farmacologia , Sulfonas/química , Fatores de Tempo , terc-Butil Hidroperóxido/farmacologia
18.
J Neurol Sci ; 166(2): 131-40, 1999 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-10475107

RESUMO

Myopathy often complicates Zidovudine (AZT) treatment in patients with acquired immunodeficiency syndrome (AIDS). The pathogenesis of the myopathy is controversial, since clinical phenomena intrinsic to AIDS may interfere per se with the onset of the myopathy. In the present work we investigated the in vivo effect of AZT in an animal model species (rat) not susceptible to HIV infection. Histochemical and electron microscopic analyses demonstrated that, under the experimental conditions used, the in vivo treatment with AZT does not cause in skeletal muscle true dystrophic lesions, but rather mitochondrial alterations confined to the fast fibers. In the same animal models, the biochemical analysis confirmed that mitochondria are the target of AZT toxicity in muscles. The effects of AZT on mitochondria energy transducing mechanisms were investigated in isolated mitochondria both in vivo and in vitro. Membrane potential abnormalities, due to a partial impairment of the respiratory chain capability observed in muscle mitochondria from AZT-treated rats, closely resemble those of control mitochondria in the presence of externally added AZT. mtDNA deletion analysis by PCR amplification and Southern blot analysis did not show any relevant deletion, while mtDNA depletion analysis demonstrated a significant decrease in mtDNA in AZT-treated rats. The present findings show that AZT causes damage to mitochondria by two mechanisms: a short-term mechanism that affects directly the respiratory chain, and a long-term mechanism that alters the mitochondrial DNA thus impairing the mitochondrial protein synthesis. In addition, the ultrastructural observations indicate that the fiber types are differently affected upon AZT treatment, which poses a number of questions as to the pathogenesis of this myopathy.


Assuntos
Fármacos Anti-HIV/efeitos adversos , DNA Mitocondrial/efeitos dos fármacos , Miopatias Mitocondriais/induzido quimicamente , Fibras Musculares Esqueléticas/efeitos dos fármacos , Zidovudina/efeitos adversos , Animais , DNA Mitocondrial/metabolismo , Feminino , Miopatias Mitocondriais/metabolismo , Miopatias Mitocondriais/patologia , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/patologia , Oxirredução , Fosforilação , Ratos , Ratos Wistar
19.
Nitric Oxide ; 3(4): 273-80, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10444366

RESUMO

The survival of skeletal muscle myoblasts in culture after exposure either to a donor of NO, sodium nitroprusside (SNP), or ethanamine, 2,2'-(hydroxynitrosohydrazono)bis-(DETA NONOate), or to a donor of both NO and O(-)(2), 3-morpholinosydnonimine hydrochloride (SIN-1), was investigated. SIN-1 reduced clonogenic survival markedly but donors of NO alone did not. The injurious effect of SIN-1 was prevented by oxyhemoglobin or by uric acid but not by superoxide dismutase. The exposure of myoblasts to authentic peroxynitrite (ONOO(-)) or to DETA NONOate in the presence of an O(-)(2)-generating system did not reduce their survival. The results show that NO or ONOO(-) alone is not detrimental to myoblast survival and suggest that SIN-1 toxicity is, at least in part, mediated by H(2)O(2) in this myoblast culture system.


Assuntos
Músculo Esquelético/efeitos dos fármacos , Nitratos/toxicidade , Doadores de Óxido Nítrico/toxicidade , Óxido Nítrico/toxicidade , Superóxidos/toxicidade , Animais , Linhagem Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Molsidomina/análogos & derivados , Molsidomina/farmacologia , Molsidomina/toxicidade , Músculo Esquelético/citologia , Nitratos/farmacologia , Óxido Nítrico/farmacologia , Doadores de Óxido Nítrico/farmacologia , Compostos Nitrosos/farmacologia , Oxiemoglobinas/farmacologia , Ratos , Superóxido Dismutase/farmacologia , Superóxidos/farmacologia , Ácido Úrico/farmacologia , Xantina Oxidase/metabolismo
20.
Nitric Oxide ; 3(1): 75-84, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10355898

RESUMO

We have used electron paramagnetic resonance to investigate the time course of nitric oxide (NO) generation and its susceptibility to inhibitors of nitric oxide synthase (NOS) in ischemia-reperfusion (IR) injury to rat skeletal muscle in vivo. Significant levels of muscle nitroso-heme complexes were detected 24 h postreperfusion, but not after at 0.05, 3, and 8 h of reperfusion. The levels of muscle nitroso-heme complexes were not decreased by the NOS inhibitor N-nitro-L-arginine methyl ester as a single dose (30 mg/kg) prior to reperfusion or as multiple doses continued throughout the reperfusion (total administered, 120 mg/kg) or by the potent NOS inhibitor S-methylisothiourea (3 mg/kg). In contrast, nitroso-heme levels were reduced by the glucocorticoid dexamethasone (2.5 mg/kg). Muscle necrosis in vitro did not result in the formation of nitroso-heme complexes. The finding that reperfusion after ischemia is necessary for NO formation suggests that an inflammatory pathway is responsible for NOS-independent NO formation in IR injury to skeletal muscle.


Assuntos
Músculo Esquelético/metabolismo , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico/biossíntese , Traumatismo por Reperfusão/metabolismo , Animais , Espectroscopia de Ressonância de Spin Eletrônica , Heme/metabolismo , Hemoglobinas/metabolismo , Masculino , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/patologia , Necrose , Ratos , Ratos Sprague-Dawley
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