Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
Mais filtros











Intervalo de ano de publicação
1.
Arq. bras. med. vet. zootec. (Online) ; 72(6): 2266-2270, Nov.-Dec. 2020. ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1142282

RESUMO

The brachiocephalic trunk and the left subclavian artery originate from the aortic arch, and both supply blood to the head, neck, and thoracic limbs. Anatomical variations, such as an aberrant right subclavian artery, are congenital conditions rarely observed in dogs, Thus, the objective of the present report was to describe a case of aberrant right subclavian artery in a 9-year-old Dalmatian. However, this anomaly was a finding in which the patient was asymptomatic during its 9 years of life and only at this age did he exhibit signs including sialorrhea, vomiting, hyporexia, and noisy deglutition. Blood count, biochemical profile, and thoracic radiography led to a diagnosis of megaesophagus and aspiration pneumonia. Despite the recommended treatment, the patient did not respond well; as such, the owner elected to euthanize the animal. On necropsy, the right subclavian artery originated directly from the aortic arch, followed a route from left to right dorsally to the esophagus, and then formed an impression of the vascular path over the muscular wall of the esophagus. The esophagus, in turn, exhibited a flaccid wall and dilation in the caudal portion to the vascular path made by the ectopic position of the right subclavian artery.(AU)


O tronco braquiocefálico e a artéria subclávia esquerda emergem do arco aórtico e são responsáveis por fazerem o suprimento sanguíneo para cabeça, pescoço e membros torácicos. Variações anatômicas, como a ectopia da artéria subclávia direita, são alterações congênitas raramente encontradas em cães, cujas alterações do sistema digestivo acontecem em pacientes recém-desmamados e não em adultos. Assim, o objetivo deste relato é descrever um caso de ectopia da artéria subclávia direita em uma cadela, Dálmata, de nove anos de idade. No entanto, essa anomalia foi um achado do qual o paciente foi assintomático durante os nove anos de vida e somente com essa idade apresentou sinais como sialorreia, vômito, hiporexia e deglutição ruidosa. O hemograma e os perfis bioquímicos, associados à radiografia torácica, levaram a um diagnóstico de megaesôfago e pneumonia aspirativa. Mesmo seguindo o tratamento recomendado, houve piora clínica do quadro e o animal foi submetido à eutanásia. À macroscopia, a artéria subclávia direita originava-se direto do arco aórtico, fazia um percurso da esquerda para a direita dorsalmente ao esôfago e, então, formava uma impressão do trajeto vascular sobre a parede muscular do esôfago. O esôfago, por sua vez, apresentava parede flácida e dilatação na porção caudal ao trajeto vascular feito pela posição ectópica da artéria subclávia direita.(AU)


Assuntos
Animais , Feminino , Cães , Artéria Subclávia/anatomia & histologia , Artéria Subclávia/anormalidades , Anormalidades Congênitas/veterinária , Acalasia Esofágica/veterinária
2.
J Environ Manage ; 200: 186-195, 2017 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-28577454

RESUMO

This work evaluates the use of biomasses and their biochars as adsorbents to remove polycyclic aromatic hydrocarbons from water. Coconut waste (CW) and orange waste (OW) were pyrolyzed at 350 °C to produce the corresponding biochars (BCW and BOW). Adsorption tests using a mixed solution of benzo(a)anthracene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(a)pyrene, and dibenzo(a,h)anthracene showed removal percentages of 30.33-83.43% (CW), 47.09-83.02% (BCW), 24.20-74.25% (OW), and 23.84-84.02% (BOW). The adsorption mechanisms appeared to involve π-π interactions of similar groups of the adsorbate and adsorbent, together with hydrophobic effects. There was no indication of competition between the PAHs for the adsorption sites, and there was evidence of cooperative adsorption. The PAHs could be desorbed from the adsorbents with efficiencies in the range 34.88-72.32%, and the reuse of the adsorbents in two further cycles demonstrated their potential for use in the removal of PAHs from water.


Assuntos
Carvão Vegetal , Hidrocarbonetos Policíclicos Aromáticos , Purificação da Água , Benzo(a)pireno , Biomassa
3.
Braz J Biol ; 75(4): 1030-4, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26675922

RESUMO

The mangrove oyster Crassostrea rhizophorae is an estuarine resource exploited by riverside communities in Northeast Brazil. Despite its socioeconomic importance, studies on the health status of this bivalve are scanty in this region. The purpose of the present study was to investigate the presence of the protozoan Perkinsus sp. in C. rhizophorae collected in August and September 2011 in three estuaries of the septentrional Northeast, Brazil: Jaguaribe (Ceará), Camurupim (Piauí) and Carnaubeiras (Maranhão) (n= 150 specimens/site). The samples were submitted to Ray's fluid thioglycollate medium (RFTM), PCR and histology assays. The RFTM assay revealed spherical, blue or bluish-black hypnospores of the genus Perkinsus in 50 specimens (Jaguaribe= 17.3%, Camurupim= 5.3%, Carnaubeiras= 10.6%). The intensity of the infection ranged from very light (1-10 cells per slide) to severe (more than 40 cells in each of 10 fields of the slide) for Jaguaribe; very light for Camurupim and very light to moderate (at least 40 cells observed in each of 10 fields of the slide) for Carnaubeiras. When submitted to confirmatory PCR analysis, 6 cases were confirmed (Jaguaribe=3, Camurupim=1, Carnaubeiras=2). The histology confirmed 21 cases of infection in specimens from the three estuaries. Although local collectors have reported no mortality in oyster populations that might be attributed to infection by Perkinsus, health surveillance of oyster populations in the septentrional region of Northeast Brazil is advisable.


Assuntos
Alveolados/fisiologia , Crassostrea/parasitologia , Interações Hospedeiro-Parasita , Animais , Brasil , Estuários , Reação em Cadeia da Polimerase , Tioglicolatos/química
4.
Braz. j. biol ; Braz. j. biol;75(4): 1030-1034, Nov. 2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-768208

RESUMO

Abstract The mangrove oyster Crassostrea rhizophorae is an estuarine resource exploited by riverside communities in Northeast Brazil. Despite its socioeconomic importance, studies on the health status of this bivalve are scanty in this region. The purpose of the present study was to investigate the presence of the protozoan Perkinsus sp. in C. rhizophorae collected in August and September 2011 in three estuaries of the septentrional Northeast, Brazil: Jaguaribe (Ceará), Camurupim (Piauí) and Carnaubeiras (Maranhão) (n= 150 specimens/site). The samples were submitted to Ray’s fluid thioglycollate medium (RFTM), PCR and histology assays. The RFTM assay revealed spherical, blue or bluish-black hypnospores of the genus Perkinsus in 50 specimens (Jaguaribe= 17.3%, Camurupim= 5.3%, Carnaubeiras= 10.6%). The intensity of the infection ranged from very light (1-10 cells per slide) to severe (more than 40 cells in each of 10 fields of the slide) for Jaguaribe; very light for Camurupim and very light to moderate (at least 40 cells observed in each of 10 fields of the slide) for Carnaubeiras. When submitted to confirmatory PCR analysis, 6 cases were confirmed (Jaguaribe=3, Camurupim=1, Carnaubeiras=2). The histology confirmed 21 cases of infection in specimens from the three estuaries. Although local collectors have reported no mortality in oyster populations that might be attributed to infection by Perkinsus, health surveillance of oyster populations in the septentrional region of Northeast Brazil is advisable.


Resumo A ostra-do-mangue Crassostrea rhizophorae é um recurso estuarino explorado por comunidades ribeirinhas do Nordeste do Brasil. Apesar de sua importância socioeconômica, estudos sobre o estado de saúde deste bivalve são escassos na região. O objetivo deste estudo foi investigar a presença do protozoário Perkinsus sp. em C. rhizophorae coletada em agosto e setembro de 2011, em três estuários da região setentrional do Nordeste brasileiro: Jaguaribe (Ceará), Camurupim (Piauí) e Carnaubeiras (Maranhão) (n = 150 espécimes/local). As amostras foram submetidas ao meio líquido de tioglicolato de Ray (RFTM), PCR e ensaios histológicos. A análise em RFTM revelou hipnósporos esféricos azuis ou preto-azulados do gênero Perkinsus em 50 espécimes (Jaguaribe= 17,3%, Camurupim= 5,3%, Carnaubeiras= 10,6%). A intensidade de infecção variou de muito leve (1-10 células por lâmina) a severa (mais de 40 células em cada um dos 10 campos da lâmina) para o Rio Jaguaribe; muito leve para o Rio Camurupim e muito leve a moderada (pelo menos 40 células observadas, em cada um dos 10 campos da lâmina) para o Rio Carnaubeiras. Quando submetidos à análise confirmatória por PCR, foram confirmados 6 casos (Jaguaribe= 3, Camurupim= 1, Carnaubeiras= 2). A histologia confirmou 21 casos de infecção em espécimes dos três estuários. Embora os coletores locais não tenham relatado nenhuma mortalidade em populações de ostras que pudesse ser atribuída à infecção por Perkinsus, é aconselhável um monitoramento sobre o estado de saúde de populações de ostras da região.


Assuntos
Animais , Alveolados/fisiologia , Crassostrea/parasitologia , Interações Hospedeiro-Parasita , Brasil , Estuários , Reação em Cadeia da Polimerase , Tioglicolatos/química
5.
Braz. J. Biol. ; 75(4): 1030-1034, Nov. 2015. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-341521

RESUMO

The mangrove oyster Crassostrea rhizophorae is an estuarine resource exploited by riverside communities in Northeast Brazil. Despite its socioeconomic importance, studies on the health status of this bivalve are scanty in this region. The purpose of the present study was to investigate the presence of the protozoan Perkinsus sp. in C. rhizophorae collected in August and September 2011 in three estuaries of the septentrional Northeast, Brazil: Jaguaribe (Ceará), Camurupim (Piauí) and Carnaubeiras (Maranhão) (n= 150 specimens/site). The samples were submitted to Rays fluid thioglycollate medium (RFTM), PCR and histology assays. The RFTM assay revealed spherical, blue or bluish-black hypnospores of the genus Perkinsus in 50 specimens (Jaguaribe= 17.3%, Camurupim= 5.3%, Carnaubeiras= 10.6%). The intensity of the infection ranged from very light (1-10 cells per slide) to severe (more than 40 cells in each of 10 fields of the slide) for Jaguaribe; very light for Camurupim and very light to moderate (at least 40 cells observed in each of 10 fields of the slide) for Carnaubeiras. When submitted to confirmatory PCR analysis, 6 cases were confirmed (Jaguaribe=3, Camurupim=1, Carnaubeiras=2). The histology confirmed 21 cases of infection in specimens from the three estuaries. Although local collectors have reported no mortality in oyster populations that might be attributed to infection by Perkinsus, health surveillance of oyster populations in the septentrional region of Northeast Brazil is advisable.(AU)


A ostra-do-mangue Crassostrea rhizophorae é um recurso estuarino explorado por comunidades ribeirinhas do Nordeste do Brasil. Apesar de sua importância socioeconômica, estudos sobre o estado de saúde deste bivalve são escassos na região. O objetivo deste estudo foi investigar a presença do protozoário Perkinsus sp. em C. rhizophorae coletada em agosto e setembro de 2011, em três estuários da região setentrional do Nordeste brasileiro: Jaguaribe (Ceará), Camurupim (Piauí) e Carnaubeiras (Maranhão) (n = 150 espécimes/local). As amostras foram submetidas ao meio líquido de tioglicolato de Ray (RFTM), PCR e ensaios histológicos. A análise em RFTM revelou hipnósporos esféricos azuis ou preto-azulados do gênero Perkinsus em 50 espécimes (Jaguaribe= 17,3%, Camurupim= 5,3%, Carnaubeiras= 10,6%). A intensidade de infecção variou de muito leve (1-10 células por lâmina) a severa (mais de 40 células em cada um dos 10 campos da lâmina) para o Rio Jaguaribe; muito leve para o Rio Camurupim e muito leve a moderada (pelo menos 40 células observadas, em cada um dos 10 campos da lâmina) para o Rio Carnaubeiras. Quando submetidos à análise confirmatória por PCR, foram confirmados 6 casos (Jaguaribe= 3, Camurupim= 1, Carnaubeiras= 2). A histologia confirmou 21 casos de infecção em espécimes dos três estuários. Embora os coletores locais não tenham relatado nenhuma mortalidade em populações de ostras que pudesse ser atribuída à infecção por Perkinsus, é aconselhável um monitoramento sobre o estado de saúde de populações de ostras da região.(AU)


Assuntos
Animais , Alveolados/fisiologia , Crassostrea/parasitologia , Interações Hospedeiro-Parasita , Brasil , Estuários , Reação em Cadeia da Polimerase , Tioglicolatos/química
6.
Oncogenesis ; 3: e123, 2014 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-25329722

RESUMO

The tumor microenvironment has a dynamic and usually cancer-promoting function during all tumorigenic steps. Glioblastoma (GBM) is a fatal tumor of the central nervous system, in which a substantial number of non-tumoral infiltrated cells can be found. Astrocytes neighboring these tumor cells have a particular reactive phenotype and can enhance GBM malignancy by inducing aberrant cell proliferation and invasion. The tumor suppressor p53 has a potential non-cell autonomous function by modulating the expression of secreted proteins that influence neighbor cells. In this work, we investigated the role of p53 on the crosstalk between GBM cells and astrocytes. We show that extracellular matrix (ECM) from p53(+/-) astrocytes is richer in laminin and fibronectin, compared with ECM from p53(+/+) astrocytes. In addition, ECM from p53(+/-) astrocytes increases the survival and the expression of mesenchymal markers in GBM cells, which suggests haploinsufficient phenotype of the p53(+/-) microenvironment. Importantly, conditioned medium from GBM cells blocks the expression of p53 in p53(+/+) astrocytes, even when DNA was damaged. These results suggest that GBM cells create a dysfunctional microenvironment based on the impairment of p53 expression that in turns exacerbates tumor endurance.

7.
Cell Death Dis ; 4: e789, 2013 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-24008733

RESUMO

Oculoleptomeningeal amyloidosis (OA) is a fatal and untreatable hereditary disease characterized by the accumulation of transthyretin (TTR) amyloid within the central nervous system. The mechanisms underlying the pathogenesis of OA, and in particular how amyloid triggers neuronal damage, are still unknown. Here, we show that amyloid fibrils formed by a mutant form of TTR, A25T, activate microglia, leading to the secretion of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and nitric oxide. Further, we found that A25T amyloid fibrils induce the activation of Akt, culminating in the translocation of NFκB to the nucleus of microglia. While A25T fibrils were not directly toxic to neurons, the exposure of neuronal cultures to media conditioned by fibril-activated microglia caused synapse loss that culminated in extensive neuronal death via apoptosis. Finally, intracerebroventricular (i.c.v.) injection of A25T fibrils caused microgliosis, increased brain TNF-α and IL-6 levels and cognitive deficits in mice, which could be prevented by minocycline treatment. These results indicate that A25T fibrils act as pro-inflammatory agents in OA, activating microglia and causing neuronal damage.


Assuntos
Neuropatias Amiloides Familiares/patologia , Transtornos da Memória/patologia , Memória de Curto Prazo , Microglia/patologia , Pré-Albumina/metabolismo , Sinapses/metabolismo , Amiloide , Neuropatias Amiloides Familiares/complicações , Neuropatias Amiloides Familiares/fisiopatologia , Animais , Encéfalo/metabolismo , Morte Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Células Cultivadas , Meios de Cultivo Condicionados/farmacologia , Modelos Animais de Doenças , Endocitose , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Mediadores da Inflamação/metabolismo , Interleucina-6/metabolismo , Transtornos da Memória/complicações , Transtornos da Memória/fisiopatologia , Memória de Curto Prazo/efeitos dos fármacos , Camundongos , Microglia/efeitos dos fármacos , Microglia/metabolismo , Minociclina/farmacologia , Mutação/genética , NF-kappa B/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fosforilação , Transporte Proteico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Sinapses/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo
8.
J Environ Manage ; 129: 216-23, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-23954388

RESUMO

This work proposes the use of tree termite nest as an adsorbent for the reduction/removal of Cr(VI) present in aqueous solution. In laboratory experiments, adsorption of Cr(VI) was sensitive to pH in the range investigated (2-5), with maximum adsorption capacity achieved at pH 2 (3.70 ± 0.04 mg g(-1), representing 93.2% removal of Cr). The termite nest was characterized by off-line pyrolysis GC/MS (py-GC/MS), infrared spectroscopy (FTIR), and electron paramagnetic resonance spectroscopy (EPR). Pyrolysis of the adsorbent produced a complex mixture of aromatic compounds, including the guaiacyl and syringilic derivatives that are characteristic of lignocellulosic materials. Infrared spectroscopy revealed deprotonation of the carboxylic acid group of the biomass with increasing pH, which was associated with a decrease in the capacity for adsorption of Cr(VI). The EPR g-factor for the termite nest samples varied between 2.0037 and 2.0038, indicating the presence of organic free radicals that were responsible for the redox reaction. A second line with g-factor values of 1.9790, only observed for the samples after contact with Cr(VI) solutions at different pH values, was assigned to Cr(III)-Cr(III) exchange coupled pairs, which explained the capacity of the adsorbent to retain a large portion of the Cr(III) ions produced after reduction of Cr(VI) to Cr(III). Fixed-bed column experiments showed that the termite nest had a maximum adsorption capacity of 18.60 mg Cr g(-1), an adsorption efficiency varying between 60.8 and 97.4%, and a desorption efficiency varying between 54.5 and 91.4%, for three successive cycles. The adsorbent presented excellent performance in the removal of chromium under acidic conditions, with the advantage that it could be regenerated and reused.


Assuntos
Cromo/química , Recuperação e Remediação Ambiental/métodos , Isópteros , Poluentes Químicos da Água/química , Poluição Química da Água/prevenção & controle , Adsorção , Animais , Espectroscopia de Ressonância de Spin Eletrônica , Cromatografia Gasosa-Espectrometria de Massas , Comportamento de Nidação , Espectroscopia de Infravermelho com Transformada de Fourier
9.
J Hazard Mater ; 209-210: 9-17, 2012 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-22321857

RESUMO

The objective of the present work was to develop a thermal desorption method for the removal of trihalomethanes (THM) adsorbed by humin, followed by multiple recycling of the fixed bed column in order to avoid excessive consumption of materials and reduce operating costs. The results obtained for adsorption on a fixed bed column confirmed the effectiveness of humin as an adsorbent, extracting between 45.9% and 90.1% of the total THM (TTHM). In none of the tests was the column fully saturated after 10h. Experiments involving thermal desorption were used to evaluate the potential of the technique for column regeneration. The adsorptive capacity of the humin bed increased significantly (p<0.05) between the first and fifth desorption cycle, by 18.9%, 18.1%, 24.2%, 20.2% and 24.2% for CHBr(3), CHBr(2)Cl, CHBrCl(2), CHCl(3) and TTHM, respectively.


Assuntos
Recuperação e Remediação Ambiental/métodos , Substâncias Húmicas , Trialometanos/química , Adsorção , Espectroscopia de Infravermelho com Transformada de Fourier
10.
Bioresour Technol ; 105: 31-9, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22178487

RESUMO

This work investigates the potentials of peat and angico hardwood sawdust to remove BTEX (benzene, toluene, ethylbenzene, and isomers of xylene) from the produced water discharged into aquatic systems during petroleum extraction. Peat and angico sawdust samples were pyrolyzed at 500°C, and found to contain n-alkenes, n-alkanes and pentacyclic triterpenes (peat), and 4-methoxyphenol, 1,4-dimethoxyphenol and 1,3,4-trimethoxyphenol (angico sawdust). In batch experiments, the removal capacities using peat were 32.4%, 50.0%, 63.0%, 67.8%, and 61.8% for benzene, toluene, ethylbenzene, m,p-xylenes and o-xylene, respectively. This compared with removal capacities using angico sawdust of 20.2%, 36.4%, 52.8%, 57.8%, and 53.7% for these compounds respectively, demonstrating the superior performance of the peat.


Assuntos
Biodegradação Ambiental , Biomassa , Biotecnologia/métodos , Petróleo , Purificação da Água/métodos , Adsorção , Benzeno/química , Derivados de Benzeno/química , Cromatografia Gasosa/métodos , Indústrias , Espectroscopia de Ressonância Magnética/métodos , Solo , Solventes/química , Temperatura , Tolueno/química , Xilenos/química
11.
Neuroscience ; 200: 130-41, 2012 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-22062133

RESUMO

Microglial activation is a key event in the progression and infiltration of tumors. We have previously demonstrated that the co-chaperone stress inducible protein 1 (STI1), a cellular prion protein (PrP(C)) ligand, promotes glioblastoma (GBM) proliferation. In the present study, we examined the influence of microglial STI1 in the growth and invasion of the human glioblastoma cell line GBM95. We demonstrated that soluble factors secreted by microglia into the culture medium (microglia conditioned medium; MG CM) caused a two-fold increase in the proliferation of GBM95 cells. This effect was reversed when STI1 was removed from the MG CM. In this context, we have shown that microglial cells synthesize and secrete STI1. Interestingly, no difference was observed in proliferation rates when GBM cells were maintained in MG CM or MG CM containing an anti-PrP(C) neutralizing antibody. Moreover, rec STI1 and rec STI1(Δ230-245), which lack the PrP(C) binding site, both promoted similar levels of GBM95 proliferation. In the migration assays, MG CM favored the migration of GBM95 cells, but migration failed when STI1 was removed from the MG CM. We detected metalloproteinase 9 (MMP-9) activity in the MG CM, and when cultured microglia were treated with an anti-STI1 antibody, MMP-9 activity decreased. Our results suggest that STI1 is secreted by microglia and favors tumor growth and invasion through the participation of MMP-9 in a PrP(C)-independent manner.


Assuntos
Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Glioblastoma/patologia , Proteínas de Choque Térmico/farmacologia , Microglia/química , Proteínas PrPC/metabolismo , Animais , Animais Recém-Nascidos , Movimento Celular/fisiologia , Células Cultivadas , Córtex Cerebral/citologia , Meios de Cultivo Condicionados/farmacologia , Relação Dose-Resposta a Droga , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Macrófagos/química , Camundongos , Camundongos Knockout , Neurônios/química , Proteínas PrPC/deficiência , Timidina/metabolismo , Fatores de Tempo , Trítio/metabolismo
12.
Bioresour Technol ; 101(10): 3345-54, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20093024

RESUMO

The objective of the present work was to assess the performance of batch and fixed bed column systems, using humin in natura and immobilized on sodium silicate, respectively, for the adsorption of the principal trihalomethanes (THMs) found in water supply systems. Kinetically, adsorption of THMs by humin follows a pseudo-second order reaction, with more than 50% removal in the first 5min for all compounds studied, and equilibrium described by the Freundlich model reached in 240min. The THM adsorption results were significant at p<0.05 for both batch (74.6-83.2% removal) and column (99.7% removal in optimized tests) experiments, and were significantly (p<0.05) influenced by flow rate and bed height. The work demonstrates the potential of humin for removal of THMs.


Assuntos
Halogênios/química , Substâncias Húmicas , Metano/química , Adsorção , Cinética
13.
J Hazard Mater ; 163(2-3): 517-23, 2009 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-18722053

RESUMO

The physicochemical characteristics of three Brazilian peats were investigated using elemental analysis, scanning electron microscopy (SEM), X-ray diffractometry (XRD) and studies of Cr(III) biosorption based on adsorption isotherms. Adsorption of Cr(III) by in natura peat from Santo Amaro das Brotas (Sergipe State) was much greater than by peats from either Ribeirão Preto (São Paulo State) or Itabaiana (Sergipe State), with adsorption capacities (q) of 4.90+/-0.01, 1.70+/-0.01 and 1.40+/-0.01 mg g(-1), respectively. Pre-treatments with HCl and NaOH+HCl reduced adsorption by the Santo Amaro das Brotas peat, showing that adsorption efficiency was associated with the amount of organic matter present. Conversely, increase in the mineral content following pre-treatment increased adsorption of Cr(III) by the Ribeirão Preto and Itabaiana peats. Highest adsorption (retention >95.0%) was achieved at equilibrium pH 4.0 using the Santo Amaro das Brotas peat. Experimental data for the adsorption of Cr(III) from aqueous solution onto this peat were fitted to the Langmuir equation, from which an equilibrium adsorption capacity, q(max), of 5.60 mg g(-1) was obtained, which was close to the experimentally determined value.


Assuntos
Cromo/isolamento & purificação , Solo/normas , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Resíduos Industriais , Purificação da Água/métodos
14.
Anal Bioanal Chem ; 375(8): 1097-100, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12733022

RESUMO

In this work the copper(II) complexation parameters of aquatic organic matter, aquatic and soil humic substances from Brazilian were determined using a new versatile approach based on a single-stage tangential-flow ultrafiltration (TF-UF) technique (cut-off 1 kDa) and sensitive atomic spectrometry methods. The results regarding the copper(II) complexation capacity and conditional stability constants obtained for humic materials were compared with those obtained using direct potentiometry with a copper-ion-selective electrode. The analytical procedure based on ultrafiltration is a good alternative to determine the complexation parameters in natural organic material from aquatic and soil systems. This approach presents additional advantages such as better sensibility, applicability for multi-element capability, and its possible to be used under natural conditions when compared with the traditional ion-selective electrode.


Assuntos
Solo/análise , Ultrafiltração/métodos , Água/química , Brasil , Cobre/química , Íons
17.
Arq. bras. endocrinol. metab ; Arq. bras. endocrinol. metab;28(3): 65-74, 1984.
Artigo em Português | LILACS | ID: lil-23208

RESUMO

Os autores apresentam dados clinicos, bioquimicos, radiologicos, cirurgicos, posoperatorios precoces e tardios de 12 casos de hiperparatiroidismo (HPT) (11 primarios e 1 secundario), operados na Secao de Cirurgia Endocrina do HSPE (11 casos) e no Hospital de Itaquera (1 caso). No diagnostico clinico, chamam a atencao para as lesoes osseas presentes em cerca de 83% dos doentes e as renais, em cerca de 66%. Dos exames laboratoriais, a calcemia total encontrava-se elevada em todos os doentes portadores de adenoma (11/11). Em todos os 11 casos de HPT primario, o adenoma localizava-se no pescoco, sendo, em 2, intratiroidianos. Em 7 casos, para facilitar a identificacao do adenoma, foi utilizado o azul de toluidina intravenoso; em 5 casos, o resultado foi excelente; num caso, nao se encontrou o adenoma na regiao cervical, nem no torax; o doente faleceu, sendo encontrado o adenoma dentro da tiroide. Em 10 dos casos de HPT primario, houve regressao do quadro clinico, laboratorial e radiologico apos a cirurgia. O tempo medio de seguimento pos-operatorio foi de 6,8 anos (1 a 13)


Assuntos
Adolescente , Adulto , Pessoa de Meia-Idade , Humanos , Masculino , Feminino , Adenoma , Neoplasias das Paratireoides , Procedimentos Cirúrgicos Operatórios
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA