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1.
Biota Neotrop. (Online, Ed. ingl.) ; 24(2): e20231560, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1564053

RESUMO

Abstract The Ibitipoca Mountains occur in southeastern Minas Gerais state, Southeast Brazil, and includes a mosaic of different vegetation types, as part of the Atlantic Forest domain. Such heterogeneity results in the occurrence of several ecotones in the region, considered essential buffer zones for maintaining biodiversity and structure among adjacent ecosystems. Given the importance of these environments for biodiversity conservation, floristic surveys are important to catalogue plant richness in natural areas, where species and landscapes have been destroyed, especially over the last decades. To contribute to increase the knowledge on the vascular Flora in the Ibitipoca Mountains, a floristic inventory was undertaken in private properties located in the boundaries of "Parque Estadual do Ibitipoca" (Ibitipoca State Park). Relevant findings of the present study include: characterization of the different vegetation types, 17 new records for the Flora of Minas Gerais, collection of 288 species never recorded in the state park (80% dissimilarity - especially due to the occurrence and size of different phytophysiognomies between these areas) and presence of 31 threatened species. In addition, discussions about conservation efforts and public policies are presented.


Resumo A Serra do Ibitipoca ocorre no sudeste do estado de Minas Gerais, sudeste do Brasil, e inclui um mosaico de diferentes tipos de vegetação, como parte do domínio da Mata Atlântica. Tal heterogeneidade é resultado da ocorrência de diversos ecótonos na região, considerados áreas de amortecimento essenciais para manutenção da biodiversidade e estrutura de ecossistemas adjacentes. Dada a importância destes ambientes para conservação da biodiversidade, inventários florísticos são importantes para catalogar a riqueza de plantas em áreas naturais, onde espécies e paisagens têm sido destruídas, especialmente nas últimas décadas. Para contribuir com o aumento do conhecimento sobre a Flora vascular na Serra do Ibitipoca, um inventário florístico foi conduzido em áreas privadas adjacentes ao Parque Estadual do Ibitipoca. As descobertas mais relevantes do presente estudo incluem: caracterização dos diferentes tipos de vegetação, 17 novos registros para a Flora de Minas Gerais, coleta de 288 espécies nunca registradas para o parque (80% de dissimilaridade - especialmente devido à ocorrência e tamanho de diferentes fitofisionomias entre as áreas) e presença de 31 espécies ameaçadas. Além disso, discussões sobre esforços para conservação e políticas públicas são apresentadas.

2.
Pathogens ; 11(1)2021 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-35055970

RESUMO

The S. mansoni adult worm n-butanol extract (Sm-AWBE) has been previously shown to contain specific S. mansoni antigens that have been used for immunodiagnosis of schistosomiasis in solid phase alkaline phosphatase immunoassay (APIA) and western blot (WB) analyses. Sm-AWBE was also used in immunoprotection studies against a fatal live-cercariae challenge in experimental mouse vaccination (~43% protection). The Sm-AWBE fraction was prepared by mixing adult worm membranous suspensions with aqueous-saturated n-butanol, centrifuging and recovering n-butanol-resistant proteins in the aqueous phase. Here we report a preliminary identification of Sm-AWBE protein components as revealed from a qualitative proteomic study after processing Sm-AWBE by 1D-gel electrophoresis, in-gel and in-solution tryptic digestions, and mass spectrometry analyses. We identified 33 proteins in Sm-AWBE, all previously known S. mansoni proteins and antigens; among them, immunomodulatory proteins and proteins mostly involved in host-parasite interactions. About 81.8% of the identified Sm-AWBE proteins are antigenic. STRING analysis showed a set of Sm-AWBE proteins configuring a small network of interactive proteins and a group of proteins without interactions. Functional groups of proteins included muscle contraction, antioxidant, GPI-anchored phosphoesterases, regulatory 14-3-3, various enzymes and stress proteins. The results widen the possibilities to design novel antigen combinations for better diagnostic and immunoprotective strategies for schistosomiasis control.

3.
Oral Dis ; 25(2): 588-595, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30362201

RESUMO

OBJECTIVE: The aim of this study was to investigate the proteome of the gingival crevicular fluid comparing the relative abundance of proteins from type 2 diabetes mellitus (2DM) individuals and chronic periodontitis (CP) affected sites, subjects affected by both conditions and healthy individuals. MATERIAL AND METHODS: Twenty individuals were equally allocated in four groups, 2DM with CP, 2DM periodontally healthy, CP without 2DM, and periodontally healthy without 2DM. The relative quantification of proteins was accessed with iTRAQ labeling and mass spectrometry. RESULTS AND CONCLUSION: A total of 104 proteins showed significant differences in abundance in pairwise comparisons. Some presented different levels in all diseased groups as compared to control, either increasing (rap guanine nucleotide exchange factor, S100A8, S100A9, and immunoglobulins) or decreasing (actins, myristoylated alanine-rich C-kinase substrate, and glutathione S-transferase). Other differences were specific for a given condition: Titin, neutrophil elastase, and myeloperoxidase levels were higher in the DP group, cathelicidin antimicrobial peptide decreased in CP, and annexin decreased in DH. These differences in the proteome can provide clues for further studies that will validate the variation in their levels and their role in both diseases.


Assuntos
Periodontite Crônica/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Líquido do Sulco Gengival/química , Proteoma/análise , Idoso , Estudos de Casos e Controles , Cromatografia Líquida , Periodontite Crônica/complicações , Diabetes Mellitus Tipo 2/complicações , Feminino , Humanos , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade
4.
Basic Res Cardiol ; 112(5): 52, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28695353

RESUMO

Ischaemic preconditioning (IPC) provides myocardial resistance to ischaemia/reperfusion (I/R) injuries. The protection afforded by IPC is not limited to the target tissue but extends to remote tissues, suggesting a mechanism mediated by humoral factors. The aim of the present study was to identify the humoral factors that are responsible for the cardioprotection induced by the coronary effluent transferred from IPC to naïve hearts. Isolated rat hearts were submitted to IPC (three cycles of 5 min I/R) before 30-min global ischaemia and 60-min reperfusion. The coronary effluent (Efl_IPC) collected during IPC was fractionated by ultrafiltration in different molecular weight ranges (<3, 3-5, 5-10, 10-30, 30-50, and >50 kDa) and evaluated for cardioprotective effects by perfusion before I/R in naïve hearts. Only the <3, 5-10 and <10 kDa fractions of hydrophobic eluate reduced I/R injuries. The cardioprotective effect of the 5-10 fraction was blocked by KATP channel blockers and a PKC inhibitor. An Efl_IPC proteomic analysis revealed 14 cytoprotection-related proteins in 4-12 kDa peptides. HSP10 perfusion protected the heart against I/R injuries. These data provide insights into the mechanisms of cardioprotection in humoral factors released by IPC. Cardioprotection is afforded by hydrophobic peptides in the 4-12 kDa size range, which activate pathways that are dependent on PKC and KATP. Fourteen 4-12 kDa peptides were identified, suggesting a potential therapeutic role for these molecules in ischaemic diseases. One of these, HSP10, identified by mass spectrometry, reduced I/R injuries and may be a potential candidate as a therapeutic target.


Assuntos
Chaperonina 10/metabolismo , Precondicionamento Isquêmico Miocárdico , Infarto do Miocárdio/prevenção & controle , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miocárdio/metabolismo , Função Ventricular Esquerda , Animais , Cromatografia Líquida , Modelos Animais de Doenças , Preparação de Coração Isolado , Canais KATP/metabolismo , Masculino , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Miocárdio/patologia , Proteína Quinase C/metabolismo , Proteômica/métodos , Ratos Wistar , Transdução de Sinais , Espectrometria de Massas por Ionização por Electrospray , Volume Sistólico , Espectrometria de Massas em Tandem , Fatores de Tempo , Pressão Ventricular
5.
Infect Genet Evol ; 51: 10-16, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28242357

RESUMO

One of the most abundant proteins in V. cholerae O1 cells grown under inorganic phosphate (Pi) limitation is PstS, the periplasmic Pi-binding component of the high-affinity Pi transport system Pst2 (PstSCAB), encoded in pst2 operon (pstS-pstC2-pstA2-pstB2). Besides its role in Pi uptake, Pst2 has been also associated with V. cholerae virulence. However, the mechanisms regulating pst2 expression and the non-stoichiometric production of the Pst2 components under Pi-limitation are unknown. A computational-experimental approach was used to elucidate the regulatory mechanisms behind pst2 expression in V. cholerae O1. Bioinformatics analysis of pst2 operon nucleotide sequence revealed start codons for pstS and pstC genes distinct from those originally annotated, a regulatory region upstream pstS containing potential PhoB-binding sites and a pstS-pstC intergenic region longer than predicted. Analysis of nucleotide sequence between pstS-pstC revealed inverted repeats able to form stem-loop structures followed by a potential RNAse E-cleavage site. Another putative RNase E recognition site was identified within the pstA-pstB intergenic sequence. In silico predictions of pst2 operon expression regulation were subsequently tested using cells grown under Pi limitation by promoter-lacZ fusion, gel electrophoresis mobility shift assay and quantitative RT-PCR. The experimental and in silico results matched very well and led us to propose a pst2 promoter sequence upstream of pstS gene distinct from the previously annotated. Furthermore, V. cholerae O1 pst2 operon transcription is PhoB-dependent and generates a polycistronic mRNA molecule that is rapidly processed into minor transcripts of distinct stabilities. The most stable was the pstS-encoding mRNA, which correlates with PstS higher levels relative to other Pst2 components in Pi-starved cells. The relatively higher stability of pstS and pstB transcripts seems to rely on the secondary structures at their 3' untranslated regions that are known to block 3'-5' exonucleolytic attacks.


Assuntos
Regulação Bacteriana da Expressão Gênica , Proteínas Periplásmicas de Ligação/genética , Proteínas de Ligação a Fosfato/genética , Processamento Pós-Transcricional do RNA , Transcrição Gênica , Vibrio cholerae O1/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Sequência de Bases , Sítios de Ligação , Transporte Biológico , Códon/química , Códon/metabolismo , Biologia Computacional , Endorribonucleases/genética , Endorribonucleases/metabolismo , Sequências Repetidas Invertidas , Óperon , Proteínas Periplásmicas de Ligação/metabolismo , Proteínas de Ligação a Fosfato/metabolismo , Fosfatos/metabolismo , Regiões Promotoras Genéticas , Ligação Proteica , Estabilidade de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Alinhamento de Sequência , Vibrio cholerae O1/metabolismo , Vibrio cholerae O1/patogenicidade , Virulência
6.
J Environ Radioact ; 151 Pt 1: 264-274, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26547362

RESUMO

The radon prone areas definition is matter of many researches in radioecology, since radon is considered a leading cause of lung tumours, therefore the authorities ask for support to develop an appropriate sanitary prevention strategy. In this paper, we use geostatistical tools to elaborate a definition accounting for some of the available information about the dwellings. Co-kriging is the proper interpolator used in geostatistics to refine the predictions by using external covariates. In advance, co-kriging is not guaranteed to improve significantly the results obtained by applying the common lognormal kriging. Here, instead, such multivariate approach leads to reduce the cross-validation residual variance to an extent which is deemed as satisfying. Furthermore, with the application of Monte Carlo simulations, the paradigm provides a more conservative radon prone areas definition than the one previously made by lognormal kriging.


Assuntos
Poluentes Radioativos do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Monitoramento de Radiação/métodos , Radônio/análise , Habitação , Análise Espacial
7.
J Environ Radioact ; 138: 208-19, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25261867

RESUMO

Studying the geographical distribution of indoor radon concentration, using geostatistical interpolation methods, has become common for predicting and estimating the risk to the population. Here we analyse the case of Friuli Venezia Giulia (FVG), the north easternmost region of Italy. Mean value and standard deviation are, respectively, 153 Bq/m(3) and 183 Bq/m(3). The geometric mean value is 100 Bq/m(3). Spatial datasets of indoor radon concentrations are usually affected by clustering and apparent non-stationarity issues, which can eventually yield arguable results. The clustering of the present dataset seems to be non preferential. Therefore the areal estimations are not expected to be affected. Conversely, nothing can be said on the non stationarity issues and its effects. After discussing the correlation of geology with indoor radon concentration It appears they are created by the same geologic features influencing the mean and median values, and can't be eliminated via a map-based approach. To tackle these problems, in this work we deal with multiple definitions of RPA, but only in quaternary areas of FVG, using extensive simulation techniques.


Assuntos
Poluentes Radioativos do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Monitoramento de Radiação/métodos , Radônio/análise , Mapeamento Geográfico , Itália , Modelos Estatísticos
8.
Rev. bras. farmacogn ; 20(5): 781-788, Oct.-Nov. 2010. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-567429

RESUMO

Ptychopetalum olacoides Benth., Olacaceae, popularly known as marapuama or muirapuama or miriantã, is a species native to the Amazonian region of Brazil. Extracts of the bark of the plant have been used traditionally for its stimulating and aphrodisiac properties and currently commercialised by the herbal industry as constituents in a wide range of phytomedicines. Fractionation by open column chromatography followed by preparative HPLC-UV/PAD of the stem bark and of three commercial extracts of P. olacoides allowed the isolation of three components that were common to all extracts analysed, and these were identified by NMR to be vanillic acid, protocatechuic acid and theobromine. Vanillic acid, which has been proposed as a phytochemical marker for P. olacoides, was employed as an external standard in the development and validation of a rapid qualitative and quantitative HPLC assay for the analyte. The recoveries values of the developed method were 99.02 percent and the LOD and LOQ values were 0.033 and 0.11 mg.L-1, respectively. The described method may be applied to the standardisation of herbs, extracts or phytomedicines commercialised as marapuama.


Ptychopetalum olacoides Benth., Olacaceae, popularmente conhecida como marapuama, muirapuama ou miriantã, é uma espécie nativa da região da Amazônia do Brasil. Extratos das cascas da planta são tradicionalmente usados por suas propriedades estimulantes e afrodisíacas, e frequentemente comercializados como constituinte de uma grande variedade de formulações fitoterápicas. O fracionamento por coluna cromatográfica aberta seguida por CLAE-UV/PAD das cascas do caule de três extratos comerciais de P. olacoides permitiram o isolamento de três substâncias comuns em todos os extratos analisados. Os compostos foram identificados por RMN como ácido vanílico, ácido protocatecuíco e teobromina. O ácido vanílico foi utilizado como marcador fitoquímico para P. olacoides e empregado como padrão externo no desenvolvimento e validação de um método de análise qualitativo e quantitativo rápido por CLAE. O valor da recuperação do método desenvolvido foi de 99,02 por cento e os valores de LOD e LOQ foram 0,033 e 0,11 mg.L-1; respectivamente. O método descrito poderá ser empregado para a padronização de plantas, extratos ou fitoterápicos comercializados como marapuama.

9.
Radiat Prot Dosimetry ; 137(3-4): 318-23, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19919960

RESUMO

The study of spatial distribution of the indoor radon has assumed in the last years a lot of interest. The geostatistical techniques turn out to be particularly promising. The present work presents the results of a study where around 4000 indoor radon data from Veneto, Friuli Venezia-Giulia and Alto Adige, collected during the sampling campaigns performed in dwellings and in schools, have been analyzed. After the definition of the common data set, the study of the spatial distribution of the phenomenon has been performed by examining the experimental variograms. Declustering techniques have been applied. Predictive maps were defined by using simulation techniques; they allow to determine the probabilities of exceeding defined concentration levels, the 'radon-prone' areas. Systematic results regarding the validation of these maps are reported. This methodological study indicates how it is possible to understand the geographical variability of the phenomenon, trying to find out correlations among indoor radon, geological characteristics (i.e. lithology, morphology, tectonics, soil gas) and building-specific features, which can significantly influence radon concentrations.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Poluição do Ar em Ambientes Fechados/estatística & dados numéricos , Poluição do Ar/análise , Poluição do Ar/estatística & dados numéricos , Interpretação Estatística de Dados , Monitoramento de Radiação/estatística & dados numéricos , Radônio/análise , Itália , Doses de Radiação
10.
Biomed Chromatogr ; 23(6): 573-80, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19277954

RESUMO

Phyllanthus niruri L., commonly known in Brazil as 'quebra-pedra', has long been used in the treatment of diverse diseases and especially urolithiasis. The therapeutic effects of P. niruri are attributed to various compounds present in the plant, including the hydrolysable tannin corilagin. In the present study, high-performance liquid chromatography (HPLC-/PAD) profiles of leaves and commercial extracts of P. niruri were examined and three compounds, found to be present in all of the samples studied, were isolated by open column chromatography over C18)silica gel followed by preparative HPLC. These compounds were identified by nuclear magnetic resonance as corilagin, rutin and ethyl 3,4,5-trihydroxybenzoate. Corilagin, which has been proposed as a phytochemical marker for P. niruri, was employed as an external standard in the development and validation of a rapid and efficient qualitative and quantitative HPLC assay for the analyte. The method may be applied in the standardization of herbs and phytomedicines commercialized in Brazil as quebra-pedra.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Ácido Gálico/análogos & derivados , Glucosídeos/análise , Phyllanthus/química , Extratos Vegetais/análise , Rutina/análise , Cromatografia Líquida de Alta Pressão/economia , Cromatografia Líquida de Alta Pressão/instrumentação , Ácido Gálico/análise , Ácido Gálico/isolamento & purificação , Taninos Hidrolisáveis , Espectroscopia de Ressonância Magnética , Folhas de Planta/química , Reprodutibilidade dos Testes , Rutina/isolamento & purificação , Sensibilidade e Especificidade , Fatores de Tempo
11.
J Radiol Prot ; 28(3): 369-78, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18714133

RESUMO

This work deals with the measurement of radioactivity and radon exhalation rate from building materials manufactured in Douala city from geological materials. Nine types of building material were surveyed for their natural radioactivity contents using high-resolution gamma-ray spectrometry. The activity concentrations for (226)Ra, (232)Th and (40)K varied from 11.5 to 49 Bq kg(-1), 16 to 37 Bq kg(-1) and 306 to 774 Bq kg(-1), respectively. The absorbed dose rate in the samples investigated at 1 m above ground level ranged from 28.5 to 66.6 nGy h(-1). External and internal hazard indices were also estimated as defined by the European Commission. The Ra equivalents of the materials studied ranged from 57.5 to 133 Bq kg(-1) and are much smaller than the recommended limit of 370 Bq kg(-1) for construction materials for dwellings. Polycarbonate nuclear track detectors (NTDs), type CR-39, were used for measuring the radon concentration from different materials. In fact, knowledge of the radon exhalation rate from building materials is important for understanding the individual contribution of each material to the total indoor radon exposure. Samples were hermetically closed in glass vessels and the radon growth was followed as a function of time. The radon exhalation rate was therefore derived from the experimental measurement of alpha-track densities. The radon exhalation varied from (5.77 +/- 0.06) x 10(-5) to (7.61 +/- 0.07) x 10(-5) Bq cm(-2) h(-1) in bricks, from (5.79 +/- 0.05) x 10(-5) to (11.6 +/- 0.12) x 10(-5) in tiles, and was (6.95 +/- 0.03) x 10(-5) Bq cm(-2) h(-1) in concrete. A correlation (correlation coefficient approximately 0.8) was found between radium concentration measured with a HPGe detector and the radon exhalation rate obtained using nuclear track detectors.


Assuntos
Materiais de Construção , Radioisótopos de Potássio/análise , Rádio (Elemento)/análise , Radônio/análise , Tório/análise , Camarões
12.
J Environ Radioact ; 99(7): 1056-60, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18272267

RESUMO

The radioactivity level of soils in a volcanic area in Cameroon was determined and discussed. Thirty soils samples were collected from Buea and Limbé cities located in the south-western Cameroon. These two regions are known for theirs volcanic grounds due to the presence of Mount Cameroon Mountain. The activity concentrations of natural radionuclides as well as that of the fission product were evaluated by gamma-ray spectrometry using a hyper-purity germanium detector (HPGe). The ranges of concentrations in the surveyed soils were 11-17 Bq kg(-1), 22-36 Bq kg(-1) and 43-201 Bq kg(-1) for (226)Ra, (232)Th and (40)K, respectively. The radioisotope (137)Cs was also found but in a very small amount. The outdoor absorbed dose rate 1m above ground with the corresponding annual effective dose rate, assuming a 20% occupancy factor was estimated. The radium equivalent and the external hazard index were also evaluated and results are compared with available data from other studies and with the world average value [United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), 1988. Sources, Effects and Risks of Ionizing Radiation. Report to the General Assembly on the Effects of Atomic Radiation. United Nations, New York; UNSCEAR, 2000. Sources and Effects of Ionizing Radiations. Report to the General Assembly with Scientific Annexes. United Nations, New York]. A solid state nuclear track detector (SSNTD), LR-115 was used for soil radon measurements at a depth of 50 cm. The ranges of soil radon concentrations were 6.7-10.8 kBq m(-3) and 5.5-8.7 kBq m(-3) in Buea and Limbé, respectively. A positive correlation was found between concentrations of radium measured with gamma-spectrometry and the soil radon concentrations measured with the nitrate cellulose detectors. The results of this study provide the radioactivity level in soil of a volcanic area, which has been found to be within the safety limits. The south-western Cameroon can be considered as having normal natural background radiation.


Assuntos
Monitoramento de Radiação/métodos , Poluentes Radioativos do Solo/análise , Erupções Vulcânicas/análise , Camarões , Geografia , Rádio (Elemento)/análise , Radônio/análise
14.
Radiat Prot Dosimetry ; 113(4): 438-41, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15788419

RESUMO

The present paper describes field performance of two different passive radon monitor devices formed, respectively, by a CR-39 track detector enclosed in a diffusion chamber and a cellulose nitrate detector (LR-115) in a heat-sealed polyethylene bag. The most important scope of these investigations was to study the performance of these detectors directly in the field. To this end, two different types of radon monitors mentioned above have been exposed simultaneously in 100 school rooms within the Italian region Friuli Venezia Giulia. Finally, the accuracy of their responses has been evaluated by exposing them under extreme humidity conditions and/or together with other radon measurement instruments.


Assuntos
Poluição do Ar em Ambientes Fechados , Colódio/química , Monitoramento de Radiação/métodos , Radiometria/métodos , Radônio/análise , Poluentes Radioativos do Ar , Difusão , Relação Dose-Resposta à Radiação , Exposição Ambiental , Itália , Plásticos , Polietileno/química , Doses de Radiação , Reprodutibilidade dos Testes , Instituições Acadêmicas
15.
Radiat Prot Dosimetry ; 111(4): 377-83, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15550706

RESUMO

Late in the summer of 1986, the Health Physics Departments of Pordenone, Udine and Trieste, entrusted with monitoring radioactivity in the environment and food as a consequence of the Chernobyl accident, started noticing high concentrations of radionuclides--especially radiocaesium--in mushroom samples coming from different areas of the Friuli Venezia Giulia region (northeast Italy). To date, the authors have conducted 14 annual rounds of sampling and gamma spectrometry measurements on mushrooms, generating a total of over 2250 samples belonging to more than 300 species, which were picked in about 30 stations in the region. This surveys the main results from 15 years of macromycetes radiocontamination analysis in the region, the still unsolved problems, and hypotheses for future work.


Assuntos
Agaricales/química , Radioisótopos de Césio/análise , Acidente Nuclear de Chernobyl , Contaminação Radioativa de Alimentos/análise , Monitoramento de Radiação , Cinza Radioativa/análise , Medição de Risco/métodos , Análise de Alimentos/métodos , Itália , Doses de Radiação , Radiometria/métodos , Fatores de Risco , Fatores de Tempo , Topografia Médica/métodos
16.
J Clin Microbiol ; 40(3): 881-5, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11880409

RESUMO

We evaluated, for the first time in Latin America, the performance of a commercial enzyme immunoassay (EIA) (Calypte Biomedical Corporation, Berkeley, Calif.) that detects human immunodeficiency virus type 1 (HIV-1)-specific antibodies in urine in comparison to standard serological assays (two commercial EIAs and a commercial Western blot [WB] assay). Paired serum and urine specimens were collected from two different groups of Brazilian patients: 225 drug users with unknown HIV status who attended drug treatment centers in Rio de Janeiro, Brazil, and 135 subjects with known HIV status. Patients showing positive results in the serum EIAs and/or in the urine EIA were serologically confirmed by WB assay. For 135 individuals with known HIV status, the urine EIA showed 100% sensitivity (74 positive samples) and 95.1% specificity (58 of 61 negative specimens). For 225 drug users, the test showed 100% sensitivity (2 positive samples) and 98.7% specificity (220 of 223 negative samples) compared to WB-confirmed serological EIA results. Thus, in a total of 360 samples, the urine EIA correctly identified all 76 HIV-positive samples and 278 of 284 negative samples (100% sensitivity and 97.9% specificity). Detailed analysis of the urine EIA results indicates that an increase of the recommended cutoff value might raise the specificity of the assay without affecting its sensitivity. Our results suggest that the HIV-1 urine EIA is a good screening test suitable for developing countries like Brazil. However, as for all other HIV screening tests on the market, it is not specific enough to be used as a one-step test and therefore requires confirmation.


Assuntos
Anticorpos Anti-HIV/urina , HIV-1/imunologia , Sorodiagnóstico da AIDS , Brasil , Humanos , Técnicas Imunoenzimáticas , Sensibilidade e Especificidade
17.
Photochem Photobiol ; 73(3): 290-6, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11281026

RESUMO

Photodynamic therapy (PDT), a cancer treatment using a photosensitizer and visible light, has been shown to induce apoptosis or necrosis. We report here that Purpurin-18 (Pu18) in combination with light induces rapid apoptotic cell death in the human leukemia cell line (HL60) at low doses and necrosis at higher concentrations. Cells treated with Pu18 and light under apoptotic conditions exhibited DNA laddering and an increase in both cellular content of subdiploid DNA and externalization of phosphatidylserine (PS), indicating DNA fragmentation and loss of membrane phospholipid asymmetry. In the absence of light activation, Pu18 at nanomolar concentrations had no detectable cytotoxic effect. Caspase-3 activity was increased even after 1 h from treatment with low doses of Pu18 and light. The PS exposure and nuclear features of apoptosis were prevented by treatment of cells before illumination with caspase inhibitors benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (Z-VAD-FMK) and benzyloxycarbonyl-Asp-Glu-Val-Asp-fluoromethylketone (Z-DEVD-FMK). Conversely, the caspase-1 inhibitor, acetyl-Tyr-Val-Ala-Asp-aldehyde (Ac-YVAD-CHO) failed to suppress the apoptosis. No protective effect of the three caspase inhibitors was observed when the cells were exposed to necrotic concentrations of Pu18 and light. Our results show that caspase-3, but not caspase-1, is involved in the signaling of apoptotic events in PDT with Pu18-induced apoptosis of HL60 cells. Moreover, both the time course of PS exposure and the effect of caspase inhibitors on it indicate that it is regulated in the same manner as DNA fragmentation.


Assuntos
Apoptose/efeitos dos fármacos , Fotoquimioterapia , Porfirinas/farmacologia , Células HL-60 , Humanos , Necrose
18.
Radiat Prot Dosimetry ; 97(4): 341-4, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11878416

RESUMO

During the year 2000 the Regional Agency for Environmental Protection (ARPA) of Friuli Venezia Giulia together with the Pordenone Province carried out a survey to determine the radon concentration in the schools. About 900 measurements have been carried out in 300 schools located both in the mountainous and in the flat territory. Moreover, geological information was gathered. both on a regional scale and, where possible, on a small detailed scale. The purpose of this study is to consider the possibility of using all the data collected to discover some radon prone areas. The first results of this study seem to locate some radon prone areas where the cover consists of very permeable gravelly deposits.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Radônio/análise , Instituições Acadêmicas , Geografia , Inquéritos Epidemiológicos , Humanos , Itália , Doses de Radiação , Monitoramento de Radiação , Radiometria
19.
J Steroid Biochem Mol Biol ; 68(3-4): 129-35, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10369410

RESUMO

The formation of oestrone sulphate has been examined in MCF-7 (oestrogen receptor positive, ER+) and MDA-MB-231 (ER negative, ER-) breast cancer cells. Using intact cell monolayers and a physiological substrate concentration, progesterone (1 microM) and dexamethasone (1 microM) both increased oestrone sulphate formation in MCF-7 cells. In MDA-MB-231 cells, dexamethasone, but not progesterone, increased conjugate formation. A number of growth factors, cytokines and human serum albumin (HSA), which have previously been found to regulate oestrogen synthesis, were also examined for their ability to regulate oestrone sulphate formation. In MCF-7 cells epidermal growth factor, acidic and basic fibroblast growth factors, insulin-like growth factor-type I and insulin all stimulated oestrone sulphate formation. The cytokines, tumour necrosis factor alpha (TNFalpha) and interleukin-1beta also increased conjugate formation in the ER+ cells, as did HSA. In contrast, in MDA-MB-231 cells TNFalpha was without effect and HSA inhibited oestrone sulphate formation. The ability to modulate oestrone sulphate formation in ER+ cells may be an important mechanism to limit the availability of oestrogen to interact with the ER.


Assuntos
Neoplasias da Mama/metabolismo , Citocinas/farmacologia , Estrona/análogos & derivados , Substâncias de Crescimento/farmacologia , Fator de Crescimento Epidérmico/farmacologia , Estrona/metabolismo , Feminino , Fator 1 de Crescimento de Fibroblastos/farmacologia , Fator 2 de Crescimento de Fibroblastos/farmacologia , Humanos , Insulina/farmacologia , Fator de Crescimento Insulin-Like I/farmacologia , Fator de Crescimento Insulin-Like II/farmacologia , Interleucina-1/farmacologia , Interleucina-2/farmacologia , Interleucina-6/farmacologia , Cinética , Receptores de Estrogênio , Albumina Sérica , Fatores de Tempo , Células Tumorais Cultivadas , Fator de Necrose Tumoral alfa/farmacologia
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