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1.
Eng. sanit. ambient ; 25(4): 583-596, jul.-ago. 2020. tab, graf
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1133804

RESUMO

RESUMO O objetivo deste estudo foi investigar as águas superficiais e os níveis foliares dos elementos-traço (Cu, Zn, Cd e Pb) da Avicennia schaueriana na área de proteção ambiental (APA) Tinharé-Boipeba, litoral sul da Bahia, com ênfase na relação entre a qualidade ambiental e o gerenciamento costeiro. Mensuraram-se in situ variáveis físico-químicas nas águas superficiais, e tomaram-se alíquotas para análises microbiológicas. Também foram coletadas folhas de árvores de mangue em nove estações amostrais. Realizou-se a leitura dos elementos-traço por espectrometria de absorção atômica com chama (F-AAS). As análises físico-químicas e microbiológicas das águas superficiais, ainda que preliminares, indicaram perda de qualidade e desafios ao saneamento, os quais merecem a atenção de autoridades sanitárias ou de saúde pública e consulta à comunidade para elaboração de soluções técnicas compatíveis com os usos da natureza e modos de vida tradicionais na APA. Os níveis foliares dos metais foram normais e não tóxicos, sendo menores do que em áreas costeiras impactadas. Os bosques de mangue encontram-se em bom estado de conservação e servem de área de referência, recomendando-se o monitoramento dos elementos-traço nas folhas ou sedimentos de mangue e qualidade da água. Esta pesquisa tem relevância à conservação dos manguezais, aos usos culturais da natureza e ao gerenciamento costeiro.


ABSTRACT The objective of this study was to investigate the surface waters and leaf levels of trace elements (Cu, Zn, Cd, and Pb) of the Avicennia schaueriana in the Tinharé-Boipeba Environmental Protection Area (APA), South Coast of Bahia, with emphasis to the relationship between environmental quality and coastal management. Physical-chemical variables were measured in situ in surface waters and aliquots were taken for microbiological analysis. Also, leaves of mangrove trees were collected at nine sampling stations. The trace element reading was performed by F-AAS. Physical-chemical and microbiological analyzes of surface water, although preliminary, indicated that there is a loss of quality and challenges to sanitation, which deserve the attention of sanitary authorities, and of public health, and consultation with the community to elaborate technical solutions compatible with the uses of nature and traditional lifestyles in APA. Leaf metal levels were normal and nontoxic, being lower than in impacted coastal areas. Mangrove forests are in good state of conservation and serve as a reference area, recommending the monitoring of trace elements in mangrove leaves or sediments and water quality. This research has relevance to the conservation of mangroves, cultural uses of nature and coastal management.

2.
Eng. sanit. ambient ; 23(1): 159-172, jan.-fev. 2018. tab, graf
Artigo em Português | LILACS | ID: biblio-891618

RESUMO

RESUMO Este trabalho teve como objetivo investigar a geoquímica e a qualidade da água subterrânea no município de Serra do Ramalho, no oeste da Bahia, com ênfase nas concentrações de nitrato (N-NO3 -). Foi coletada água do Aquífero Bambuí, cárstico, em 26 poços tubulares nas campanhas de 2010 e 2011 (período chuvoso) e 2012 (período seco). Foram realizadas medidas in situ de variáveis físico-químicas e tomadas alíquotas para análises laboratoriais dos ânions (titrimetria e espectrofotometria) e cátions principais (ICP OES) e do fluoreto (SPANDS). O pH variou entre 6,6 e 8,7, cujos teores dos elementos principais foram, em ordem decrescente: rCa2+ > rNa+ > rMg2+ > rK+ e rCO3 2- - rHCO3 - > rCl- > rSO4 2- > rNO3- > rF-. As fácies hidrogeoquímicas bicarbonatadas cálcicas (49%), cloretadas cálcicas (21%) e mistas cálcicas (15%) foram as mais representativas. As concentrações de nitrato e fluoreto excederam o limite de potabilidade preconizado pela Portaria nº 2.914/2011 em 25 e 12% dos poços, respectivamente. A poluição da água subterrânea representa um desafio para a gestão dos recursos hídricos, o saneamento, o uso do solo e a saúde pública, devendo ser mais bem compreendida, monitorada e remediada.


ABSTRACT This study aimed to characterize groundwater geochemistry and quality in the municipality of Serra do Ramalho, west Bahia, with emphasis on nitrate (N-NO3 -) concentrations. Water was sampled from 26 tubular wells during 2010 and 2011 (rainy season) and 2012 (dry season). Physicochemical parameters were measured and groundwater was sampled in each sampling station for laboratory analyses of the main anions (titrimetry and spectrophotometry) and cations (ICP OES) and fluoride (SPANDS). The pH ranged from 6.60 to 8.70, with the following decreasing order of major elements: rCa2+ > rNa+ > rMg2+ > rK+ and rCO3 2- - rHCO3 - > rCl- > rSO4 2- > rNO3- > rF-. Calcic bicarbonated hydrochemical facies (49%), calcic chlorinated facies (21%) and calcic mixed facies (15%) were the most representative in the study area. Fluoride and nitrate concentrations were above potability limit in 25 and 12% of the wells, respectively. Groundwater pollution is a challenge to the management of water resources, sanitation, land use and public health, and should be better understood, monitored and remedied.

3.
Biosci. j. (Online) ; 30(3): 750-762, may/june 2014. ilus, tab
Artigo em Português | LILACS | ID: biblio-947319

RESUMO

A macaúba (Acrocomia aculeata) é uma alternativa para a produção de biodiesel e, consorciada com pastagem, pode auxiliar na recuperação de áreas degradadas. O objetivo deste trabalho foi estudar as alterações nos atributos microbiológicos, na matéria orgânica e no N total do solo, em função da variação sazonal e espacial em um Gleissolo sob maciço de macaubeiras nativas, no Cerrado. O estudo observacional foi realizado na região de Planaltina de Goiás, na Fazenda Agropecuária Santa Fé. Foram selecionadas dez árvores em uma mata com macaubeiras nativas no bioma cerrado. A coleta de solo foi realizada na camada de 0 a 10 centímetros de profundidade, sob uma linha horizontal, imaginária, traçada a partir da base do caule das macaubeiras. As amostras de solo foram coletadas a 50, 150 e 250 centímetros de distância do caule da palmeira, durante o verão chuvoso (março de 2010) e inverno seco (julho 2010). Para a avaliação estatística das variáveis observadas, utilizou-se um modelo misto. As médias das variáveis observadas foram submetidas a testes para verificar se seguiam a distribuição normal, e a homogeneidade de variâncias. Em seguida, os dados foram submetidos ao teste F e as médias foram comparadas pelo teste t. Os atributos carbono microbiano (Cmic), respiração basal (RB), quociente metabólico (qCO2), a matéria orgânica do solo (MOS) e a relação C/N do solo são sensíveis à variação sazonal e espacial em mata de macaubeiras no Cerrado. O nitrogênio total (NT) foi sensível à variação espacial. A microbiota presente no solo sob macaubal se manteve mais equilibrada durante o período seco, apresentando maiores teores de carbono microbiano e quociente microbiano e menor quociente metabólico e relação C/N do solo.


Macauba palm (Acrocomia aculeata) is an alternative for biodiesel production and intercropped with pastures, can be used to recover degraded areas. The aim of this paper was to study the alterations of microbial and soil organic matter and total N, in function of sazonal and spatial variation of a Gleysol, under native macauba palms (Acrocomia aculeata). This observational study took place in Santa Fe Agropecuaria farm, in the region of Planaltina de Goias, State of Goias. Ten trees were selected from a native forest containing macauba palms. Soil samples were then taken at a depth of 0 - 10 cm from a horizontal imaginary line, drawn from the macauba`s palm trunk. Soil samples were taken from a 50, 150 and 250 cm distance from the trunk, during the wet summer (March, 2010) and the dry winter (July, 2010). The mixed model was used in order to evaluate the observational study. The observational means were submitted to testing to evaluate if their values followed a normal distribution and to test homogeneity of variance. Subsequently, data were submitted to the F-test and the means were compared using the t-test. The Cmic, RB, qCO2 and the MO and soil C/N have been found to be sensitive to seasonal and spatial variation in the native forest of macauba palms, in the Cerrado. The NT showed to be sensitive to spatial variation. The microbiota present in the soil under macauba palms was more efficient and maintained a higher equilibrium during the dry winter, presenting higher values of Cmic and Cmic:Corg, and lower values of qCO2 and soil C/N ratio.


Assuntos
Estações do Ano , Qualidade do Solo , Arecaceae , Matéria Orgânica , Biocombustíveis
4.
J Biol Chem ; 286(28): 25211-23, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21532034

RESUMO

Myelodysplastic syndromes (MDS) are characterized by abnormal and dysplastic maturation of all blood lineages. Even though epigenetic alterations have been seen in MDS marrow progenitors, very little is known about the molecular alterations in dysplastic peripheral blood cells. We analyzed the methylome of MDS leukocytes by the HELP assay and determined that it was globally distinct from age-matched controls and was characterized by numerous novel, aberrant hypermethylated marks that were located mainly outside of CpG islands and preferentially affected GTPase regulators and other cancer-related pathways. Additionally, array comparative genomic hybridization revealed that novel as well as previously characterized deletions and amplifications could also be visualized in peripheral blood leukocytes, thus potentially reducing the need for bone marrow samples for future studies. Using integrative analysis, potentially pathogenic genes silenced by genetic deletions and aberrant hypermethylation in different patients were identified. DOCK4, a GTPase regulator located in the commonly deleted 7q31 region, was identified by this unbiased approach. Significant hypermethylation and reduced expression of DOCK4 in MDS bone marrow stem cells was observed in two large independent datasets, providing further validation of our findings. Finally, DOCK4 knockdown in primary marrow CD34(+) stem cells led to decreased erythroid colony formation and increased apoptosis, thus recapitulating the bone marrow failure seen in MDS. These findings reveal widespread novel epigenetic alterations in myelodysplastic leukocytes and implicate DOCK4 as a pathogenic gene located on the 7q chromosomal region.


Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 7/metabolismo , Epigênese Genética , Proteínas Ativadoras de GTPase/biossíntese , Leucócitos/metabolismo , Síndromes Mielodisplásicas/metabolismo , Apoptose/genética , Células da Medula Óssea/metabolismo , Células da Medula Óssea/patologia , Cromossomos Humanos Par 7/genética , Ilhas de CpG/genética , Metilação de DNA/genética , Feminino , Proteínas Ativadoras de GTPase/genética , Marcadores Genéticos , Humanos , Leucócitos/patologia , Masculino , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/patologia , Células-Tronco/metabolismo , Células-Tronco/patologia
5.
Cancer Res ; 71(3): 955-63, 2011 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-21189329

RESUMO

Even though myelodysplastic syndromes (MDS) are characterized by ineffective hematopoiesis, the molecular alterations that lead to marrow failure have not been well elucidated. We have previously shown that the myelosuppressive TGF-ß pathway is constitutively activated in MDS progenitors. Because there is conflicting data about upregulation of extracellular TGF-ß levels in MDS, we wanted to determine the molecular basis of TGF-ß pathway overactivation and consequent hematopoietic suppression in this disease. We observed that SMAD7, a negative regulator of TGF-ß receptor I (TBRI) kinase, is markedly decreased in a large meta-analysis of gene expression studies from MDS marrow-derived CD34(+) cells. SMAD7 protein was also found to be significantly decreased in MDS marrow progenitors when examined immunohistochemically in a bone marrow tissue microarray. Reduced expression of SMAD7 in hematopoietic cells led to increased TGF-ß-mediated gene transcription and enhanced sensitivity to TGF-ß-mediated suppressive effects. The increased TGF-ß signaling due to SMAD7 reduction could be effectively inhibited by a novel clinically relevant TBRI (ALK5 kinase) inhibitor, LY-2157299. LY-2157299 could inhibit TGF-ß-mediated SMAD2 activation and hematopoietic suppression in primary hematopoietic stem cells. Furthermore, in vivo administration of LY-2157299 ameliorated anemia in a TGF-ß overexpressing transgenic mouse model of bone marrow failure. Most importantly, treatment with LY-2157199 stimulated hematopoiesis from primary MDS bone marrow specimens. These studies demonstrate that reduction in SMAD7 is a novel molecular alteration in MDS that leads to ineffective hematopoiesis by activating of TGF-ß signaling in hematopoietic cells. These studies also illustrate the therapeutic potential of TBRI inhibitors in MDS.


Assuntos
Síndromes Mielodisplásicas/tratamento farmacológico , Síndromes Mielodisplásicas/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Pirazóis/farmacologia , Quinolinas/farmacologia , Receptores de Fatores de Crescimento Transformadores beta/antagonistas & inibidores , Proteína Smad7/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Anemia/tratamento farmacológico , Anemia/metabolismo , Anemia/patologia , Hematopoese/efeitos dos fármacos , Células-Tronco Hematopoéticas/metabolismo , Humanos , Células K562 , Síndromes Mielodisplásicas/sangue , Síndromes Mielodisplásicas/enzimologia , Proteínas Serina-Treonina Quinases/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo I , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Crescimento Transformador beta/antagonistas & inibidores
6.
Am J Hematol ; 84(10): 688-9, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19722261
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