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1.
Dis Aquat Organ ; 136(2): 147-155, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31621647

RESUMO

Infection caused by the fungus Batrachochytrium dendrobatidis (Bd) produces chytridiomycosis, a disease considered one of the main causes of amphibian population declines in the world. In Brazil, Bd has been recorded in several regions, but mainly in the Atlantic Forest biome. This study aimed to investigate the occurrence of Bd in amphibian species in Bahia State to test the hypothesis that Bd is widespread in other Brazilian biomes. Using histological analysis, we evaluated the skin of 190 anurans of 85 species preserved in herpetological collections. Based on these analyses, the distribution of Bd was extended approximately 400 km to the west, 150 km to the north and 105 km to the east in the state of Bahia. Of the 190 specimens analyzed, Bd infection was diagnosed in 16 individuals, from 14 species, with the earliest record from a specimen collected in 1996 in the Caatinga biome. We identified Bd in 13 adult specimens, including 2 individuals showing suggestive signs of the disease (loss of skin pigmentation). In tadpoles, we recorded fungal structures in the oral region and on the epidermis adjacent to the rows of teeth. The results of this study corroborate the prediction that Bd is widespread in the Atlantic Forest biome, and suggest that it is widespread in the other biomes of the state (Cerrado and Caatinga, at least since 1996). Conservation efforts should involve long-term studies aimed at providing information on the dynamics of the infection, its relationship with its host and its effect on amphibian populations.


Assuntos
Quitridiomicetos , Micoses , Animais , Anuros , Brasil , Ecossistema
2.
J Fish Biol ; 95(4): 1156-1160, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31390056

RESUMO

Morphometric measurements, meristic counts and DNA barcoding identified the presence of a biglip grunt Plectorhinchus macrolepis in the western Atlantic Ocean. As the species is endemic to the tropical eastern Atlantic Ocean and has not previously been reported in the western Atlantic Ocean, we discuss the possible means by which it might have dispersed to the western Atlantic Ocean. Even though this species is not considered established in Paranaguá Bay, we advocate monitoring of possible new individuals and other exotic fish species.


Assuntos
Distribuição Animal , Peixes/genética , Animais , Oceano Atlântico
3.
Mar Pollut Bull ; 114(1): 123-133, 2017 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-27641110

RESUMO

The Abrolhos Bank is an area of high ecological, socio-economic importance and harbour the richest and most-extensive coral reefs in the South Atlantic. Here we report the discovery of shallow (12-25m depth) reef complex with ten large biogenic structures, intermediate between the typical mushroom-shaped pinnacles of the northern Abrolhos Bank (17°-18° S) and the small patch reefs found on the central/southern coast of the Espírito Santo State (19°-20° S). The newly discovered reefs harbour a relatively rich and abundant reef community, with 73 fish and 14 benthic cnidarian species, including endangered and commercially important ones. We discuss on urgent needs of properly mapping and understanding the ecological functioning of this reef system. Information provided here is a baseline for future impact evaluations, particularly considering the recent worst environmental disaster of Brazil from a dam collapse in Doce river that affected the region.


Assuntos
Conservação dos Recursos Naturais , Recifes de Corais , Animais , Antozoários/crescimento & desenvolvimento , Brasil , Ecologia , Meio Ambiente , Peixes , Poluição da Água/prevenção & controle , Poluição da Água/estatística & dados numéricos
4.
Braz J Med Biol Res ; 49(12): e5519, 2016 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-27982280

RESUMO

The presence of the single nucleotide polymorphisms in exon 1 of the mannose-binding lectin 2 (MBL2) gene was evaluated in a sample of 159 patients undergoing coronary artery bypass surgery (71 patients undergoing valve replacement surgery and 300 control subjects) to investigate a possible association between polymorphisms and heart disease with Chlamydia infection. The identification of the alleles B and D was performed using real time polymerase chain reaction (PCR) and of the allele C was accomplished through PCR assays followed by digestion with the restriction enzyme. The comparative analysis of allelic and genotypic frequencies between the three groups did not reveal any significant difference, even when related to previous Chlamydia infection. Variations in the MBL plasma levels were influenced by the presence of polymorphisms, being significantly higher in the group of cardiac patients, but without representing a risk for the disease. The results showed that despite MBL2 gene polymorphisms being associated with the protein plasma levels, the polymorphisms were not enough to predict the development of heart disease, regardless of infection with both species of Chlamydia.


Assuntos
Infecções por Chlamydia/sangue , Infecções por Chlamydia/genética , Doenças das Valvas Cardíacas/microbiologia , Lectina de Ligação a Manose/sangue , Lectina de Ligação a Manose/genética , Estudos de Casos e Controles , Infecções por Chlamydia/diagnóstico , Estudos Transversais , Feminino , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Doenças das Valvas Cardíacas/sangue , Doenças das Valvas Cardíacas/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único
5.
Braz. j. med. biol. res ; 49(12): e5519, 2016. tab, graf
Artigo em Inglês | LILACS | ID: biblio-828177

RESUMO

The presence of the single nucleotide polymorphisms in exon 1 of the mannose-binding lectin 2 (MBL2) gene was evaluated in a sample of 159 patients undergoing coronary artery bypass surgery (71 patients undergoing valve replacement surgery and 300 control subjects) to investigate a possible association between polymorphisms and heart disease with Chlamydia infection. The identification of the alleles B and D was performed using real time polymerase chain reaction (PCR) and of the allele C was accomplished through PCR assays followed by digestion with the restriction enzyme. The comparative analysis of allelic and genotypic frequencies between the three groups did not reveal any significant difference, even when related to previous Chlamydia infection. Variations in the MBL plasma levels were influenced by the presence of polymorphisms, being significantly higher in the group of cardiac patients, but without representing a risk for the disease. The results showed that despite MBL2 gene polymorphisms being associated with the protein plasma levels, the polymorphisms were not enough to predict the development of heart disease, regardless of infection with both species of Chlamydia.


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Infecções por Chlamydia/sangue , Infecções por Chlamydia/genética , Doenças das Valvas Cardíacas/microbiologia , Lectina de Ligação a Manose/sangue , Lectina de Ligação a Manose/genética , Estudos de Casos e Controles , Infecções por Chlamydia/diagnóstico , Estudos Transversais , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Doenças das Valvas Cardíacas/sangue , Doenças das Valvas Cardíacas/cirurgia , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único
6.
Transpl Infect Dis ; 13(6): 633-7, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21414116

RESUMO

The present study investigated the prevalence of infection by JC and BK polyomaviruses (JCV and BKV) in patients with chronic renal disease (CRD), kidney transplant recipients, and a control group of asymptomatic subjects. We tested a total of 295 urine samples. After DNA extraction, polymerase chain reaction assay was used to amplify a fragment of 173 bp of the polyomavirus T antigen, followed by analysis using the BamHI restriction endonuclease. Infection by polyomavirus was detected in 17.6% (52/295 subjects) of the subjects. Whereas 30.5% (18/59) of transplant recipients were infected, the frequency was only 22.4% (30/134) in the control subjects, and 3.9% (4/102) in the CRD group (all JCV). The vast majority of infections (88.9%; 16/18) in transplant recipients were of the BKV type, whereas this type was absent in CRD patients, and made up only 10.0% (3/30) of infections in the control group. The risk of BKV infection was 72 times greater in renal transplant patients than in asymptomatic subjects. The low frequency of infection found in CRD patients may have been related to elevated levels of urea excreted in the urine, together with reduced urine volume and cell content. These factors may combine to reduce viral load or inhibit amplification. The results of the study indicate a need for the routine screening for polyomavirus in pre- and post-transplant patients, as well as organ donors, considering that BKV infection has been associated with graft rejection in kidney transplants.


Assuntos
Falência Renal Crônica/complicações , Transplante de Rim , Infecções por Polyomavirus/epidemiologia , Complicações Pós-Operatórias , Infecções Tumorais por Vírus/epidemiologia , Adulto , Vírus BK/genética , Vírus BK/isolamento & purificação , DNA Viral/urina , Feminino , Humanos , Vírus JC , Masculino , Reação em Cadeia da Polimerase , Infecções por Polyomavirus/complicações , Infecções Tumorais por Vírus/complicações
7.
Mem Inst Oswaldo Cruz ; 103(7): 645-9, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19057812

RESUMO

The present study investigated the prevalence of mutations in the -550 (H/L) and -221 (X/Y) mannose-binding lectin (MBL) gene promoter regions and their impact on infection by human immunodeficiency virus 1 (HIV-1) in a population of 128 HIV-1 seropositive and 97 seronegative patients. The allele identification was performed through the sequence-specific primer polymerase chain reaction method, using primer sequences specific to each polymorphism. The evolution of the infection was evaluated through CD4+ T-lymphocyte counts and plasma viral load. The allele and haplotype frequencies among HIV-1-infected patients and seronegative healthy control patients did not show significant differences. CD4+ T-lymphocyte counts showed lower levels among seropositive patients carrying haplotypes LY, LX and HX, as compared to those carrying the HY haplotype. Mean plasma viral load was higher among seropositive patients with haplotypes LY, LX and HX than among those carrying the HY haplotype. When promoter and exon 1 mutations were matched, it was possible to identify a significantly higher viral load among HIV-1 infected individuals carrying haplotypes correlated to low serum levels of MBL. The current study shows that haplotypes related to medium and low MBL serum levels might directly influence the evolution of viral progression in patients. Therefore, it is suggested that the identification of haplotypes within the promoter region of the MBL gene among HIV-1 infected persons should be further evaluated as a prognostic tool for AIDS progression.


Assuntos
Infecções por HIV/genética , HIV-1/genética , Lectina de Ligação a Manose/genética , Polimorfismo Genético/genética , Contagem de Linfócito CD4 , Estudos de Casos e Controles , Progressão da Doença , Marcadores Genéticos/genética , Predisposição Genética para Doença/genética , Infecções por HIV/virologia , Soronegatividade para HIV/genética , Haplótipos/genética , Humanos , Mutação , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas/genética , Carga Viral
8.
Mem. Inst. Oswaldo Cruz ; 102(8): 991-994, Dec. 2007. tab
Artigo em Inglês | LILACS | ID: lil-471849

RESUMO

The present study investigated the frequency of the mutations at positions -550 and -221 of the mannose-binding lectin (MBL) gene in a sample of 75 human T-cell lymphotropic virus (HTLV) infected patients and 96 HTLV seronegative controls, in order to evaluate the occurrence of a possible association between the polymorphism and HTLV infection. A sequence specific primer-polymerase chain reaction was used for discrimination of the polymorphism. The analysis of allele frequencies at position -550 did not show any significant differences between HTLV infected group and controls, but there was a significant difference at position -221. The comparative analysis of haplotypes frequencies were not significant, but the genotype frequencies between the two groups, revealed a higher prevalence of genotype LYLX (25.3 percent), associated with medium and low MBL serum levels among HTLV infected subjects. The odds ratio estimation demonstrated that the presence of genotype LYLX was associated with an increased risk of HTLV infection (p = 0.0096; 1.38 < IC95 percent < 7.7605). There was no association between proviral load and the promoter polymorphism, but when promoter and exon 1 mutations were matched, it was possible to identify a significant higher proviral load among HTLV infected individuals carrying haplotypes correlated to low serum levels of MBL. The present study shows that the polymorphism in the promoter region of the MBL gene may be a genetic marker associated with HTLV infection, and emphasizes the need for further studies to determinate if the present polymorphism have any impact on diseases linked to HTLV infection.


Assuntos
Adulto , Feminino , Humanos , Masculino , Infecções por HTLV-I/virologia , Infecções por HTLV-II/virologia , Vírus Linfotrópico T Tipo 1 Humano/genética , /genética , Lectina de Ligação a Manose/genética , Polimorfismo Genético/genética , Estudos de Casos e Controles , Suscetibilidade a Doenças , Marcadores Genéticos/genética , Haplótipos , Mutação/genética , Reação em Cadeia da Polimerase
9.
Mem Inst Oswaldo Cruz ; 102(8): 991-4, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18209939

RESUMO

The present study investigated the frequency of the mutations at positions -550 and -221 of the mannose-binding lectin (MBL) gene in a sample of 75 human T-cell lymphotropic virus (HTLV) infected patients and 96 HTLV seronegative controls, in order to evaluate the occurrence of a possible association between the polymorphism and HTLV infection. A sequence specific primer-polymerase chain reaction was used for discrimination of the polymorphism. The analysis of allele frequencies at position -550 did not show any significant differences between HTLV infected group and controls, but there was a significant difference at position -221. The comparative analysis of haplotypes frequencies were not significant, but the genotype frequencies between the two groups, revealed a higher prevalence of genotype LYLX (25.3%), associated with medium and low MBL serum levels among HTLV infected subjects. The odds ratio estimation demonstrated that the presence of genotype LYLX was associated with an increased risk of HTLV infection (p = 0.0096; 1.38 < or = IC95% < or = 7.7605). There was no association between proviral load and the promoter polymorphism, but when promoter and exon 1 mutations were matched, it was possible to identify a significant higher proviral load among HTLV infected individuals carrying haplotypes correlated to low serum levels of MBL. The present study shows that the polymorphism in the promoter region of the MBL gene may be a genetic marker associated with HTLV infection, and emphasizes the need for further studies to determinate if the present polymorphism have any impact on diseases linked to HTLV infection.


Assuntos
Infecções por HTLV-I/virologia , Infecções por HTLV-II/virologia , Vírus Linfotrópico T Tipo 1 Humano/genética , Vírus Linfotrópico T Tipo 2 Humano/genética , Lectina de Ligação a Manose/genética , Polimorfismo Genético/genética , Adulto , Estudos de Casos e Controles , Suscetibilidade a Doenças , Feminino , Marcadores Genéticos/genética , Haplótipos , Humanos , Masculino , Mutação/genética , Reação em Cadeia da Polimerase
10.
Mem Inst Oswaldo Cruz ; 101(1): 103-5, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16699718

RESUMO

Antibodies to human T-cell lymphotropic virus-1 and 2 (HTLV-1 and 2) were tested in 259 inhabitants (98 males and 161 females) of four villages of the Marajó Island (Pará, Brazil) using enzyme immunoassays (ELISA and Western blot). Types and subtypes of HTLV were determined by nested polymerase chain reaction (PCR) targeting the pX, env and 5 LTR regions. HTLV-1 infection was detected in Santana do Arari (2.06%) and Ponta de Pedras (1%). HTLV-2 was detected only in Santana do Arari (1.06%). Sequencing of the 5 LTR region of HTLV-1 and the phylogenetic analysis identified the virus as a member of the Cosmopolitan Group, subgroup Transcontinental. Santana do Arari is an Afro-Brazilian community and the current results represent the first report of HTLV-1 infection in a mocambo located in the Brazilian Amazon region.


Assuntos
Anticorpos Anti-HTLV-I/sangue , Infecções por HTLV-I/diagnóstico , Infecções por HTLV-II/diagnóstico , Vírus Linfotrópico T Tipo 1 Humano/imunologia , Vírus Linfotrópico T Tipo 2 Humano/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , População Negra , Western Blotting , Brasil/etnologia , Criança , Pré-Escolar , Ensaio de Imunoadsorção Enzimática , Feminino , Infecções por HTLV-I/etnologia , Infecções por HTLV-II/etnologia , Vírus Linfotrópico T Tipo 1 Humano/genética , Vírus Linfotrópico T Tipo 2 Humano/genética , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
11.
Mem. Inst. Oswaldo Cruz ; 101(1): 103-105, Feb. 2006.
Artigo em Inglês | LILACS | ID: lil-430848

RESUMO

Antibodies to human T-cell lymphotropic virus-1 and 2 (HTLV-1 and 2) were tested in 259 inhabitants (98 males and 161 females) of four villages of the Marajó Island (Pará, Brazil) using enzyme immunoassays (ELISA and Western blot). Types and subtypes of HTLV were determined by nested polymerase chain reaction (PCR) targeting the pX, env and 5 LTR regions. HTLV-1 infection was detected in Santana do Arari (2.06 percent) and Ponta de Pedras (1 percent). HTLV-2 was detected only in Santana do Arari (1.06 percent). Sequencing of the 5 LTR region of HTLV-1 and the phylogenetic analysis identified the virus as a member of the Cosmopolitan Group, subgroup Transcontinental. Santana do Arari is an Afro-Brazilian community and the current results represent the first report of HTLV-1 infection in a mocambo located in the Brazilian Amazon region.


Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Criança , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , População Negra , Anticorpos Anti-HTLV-I/sangue , Infecções por HTLV-I/diagnóstico , Infecções por HTLV-II/diagnóstico , Vírus Linfotrópico T Tipo 1 Humano/imunologia , /imunologia , Western Blotting , Brasil/etnologia , Ensaio de Imunoadsorção Enzimática , Infecções por HTLV-I/etnologia , Infecções por HTLV-II/etnologia , Vírus Linfotrópico T Tipo 1 Humano/genética , /genética , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
12.
Hum Immunol ; 66(8): 892-6, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16216673

RESUMO

The present study investigated the association between mannose-binding lectin (MBL) gene polymorphism and the susceptibility to human T-cell lymphotropic virus (HTLV) infection in a group of 83 HTLV-infected asymptomatic subjects (62 HTLV-1 and 21 HTLV-2) and 99 healthy controls. Detection of MBL*A, MBL*B, and MBL*C was performed by amplifying a fragment of 349 bp (exon 1) and submitting the product to restriction fragment length polymorphism analysis with BanI and MboII endonucleases. Allele MBL*D was investigated by sequence-specific primer-polymerase chain reaction. The frequency of MBL*A, MBL*B, and MBL*D was 63%, 22%, and 15% among seropositive subjects and 70%, 14%, and 16% among healthy controls, respectively. Genotype differences were statistically significant (chi2 = 11.57; p = 0.04); the presence of genotype BB was 9.6% among HTLV-infected patients compared with 1% among controls (chi2 = 7.151; p = 0.019). A significant difference of the genotype frequencies between HTLV-1 and HTLV-2 infections was observed, but this result could be attributed to the number of investigated HTLV-1-infected subjects. The odds ratio to the presence of BB genotype was 10.453 (1.279 < or = IC95% < or = 85.40; p = 0.019). Results reveal a strong association between MBL polymorphism and HTLV infection. Presence of genotype BB may be associated with the susceptibility to HTLV, but further studies, with a larger number of individuals, will be necessary. MBL polymorphism could possibly have an impact on diseases associated with HTLV infection.


Assuntos
Infecções por Deltaretrovirus/virologia , Vírus Linfotrópico T Tipo 1 Humano/genética , Vírus Linfotrópico T Tipo 2 Humano/genética , Lectina de Ligação a Manose/genética , Polimorfismo Genético/genética , Genótipo , Humanos
13.
Mem Inst Oswaldo Cruz ; 100(4): 371-6, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16113884

RESUMO

The present work evaluated the epidemiology of human immunodeficiency virus 1/human T-cell lymphotropic virus (HIV-1/HTLV) coinfection in patients living in Belém (state of Pará) and Macapá (state of Amapá), two cities located in the Amazon region of Brazil. A total of 169 blood samples were collected. The sera were tested by enzyme-linked immunosorbent assay to determine the presence of antibodies anti-HTLV-1/2. Confirmation of infection and discrimination of HTLV types and subtypes was performed using a nested polymerase chain reaction targeting the pX and 5' LTR regions, followed by restriction fragment length polymorphism and sequencing analysis. The presence of anti-HTLV1/2 was detected in six patients from Belém. The amplification of the pX region followed by RFLP analysis, demonstrated the presence of HTLV-1 and HTLV-2 infections among two and four patients, respectively. Sequencing HTLV-1 5' LTR indicated that the virus is a member of the Cosmopolitan Group, Transcontinental subgroup. HTLV-2 strains isolated revealed a molecular profile of subtype HTLV-2c. These results are a reflex of the epidemiological features of HIV-1/HTLV-1/2 coinfection in the North region of Brazil, which is distinct from other Brazilian regions, as reported by previous studies.


Assuntos
Infecções por HIV/complicações , HIV-1 , Infecções por HTLV-I/epidemiologia , Infecções por HTLV-II/epidemiologia , Vírus Linfotrópico T Tipo 1 Humano/genética , Vírus Linfotrópico T Tipo 2 Humano/genética , Brasil/epidemiologia , Feminino , Infecções por HTLV-I/virologia , Infecções por HTLV-II/virologia , Humanos , Masculino , Filogenia , Prevalência
14.
Mem. Inst. Oswaldo Cruz ; 100(4): 371-376, July 2005. ilus, tab
Artigo em Inglês | LILACS | ID: lil-405991

RESUMO

The present work evaluated the epidemiology of human immunodeficiency virus 1/human T-cell lymphotropic virus (HIV-1/HTLV) coinfection in patients living in Belém (state of Pará) and Macapá (state of Amapá), two cities located in the Amazon region of Brazil. A total of 169 blood samples were collected. The sera were tested by enzyme-linked immunosorbent assay to determine the presence of antibodies anti-HTLV-1/2. Confirmation of infection and discrimination of HTLV types and subtypes was performed using a nested polymerase chain reaction targeting the pX and 5' LTR regions, followed by restriction fragment length polymorphism and sequencing analysis. The presence of anti-HTLV1/2 was detected in six patients from Belém. The amplification of the pX region followed by RFLP analysis, demonstrated the presence of HTLV-1 and HTLV-2 infections among two and four patients, respectively. Sequencing HTLV-1 5' LTR indicated that the virus is a member of the Cosmopolitan Group, Transcontinental subgroup. HTLV-2 strains isolated revealed a molecular profile of subtype HTLV-2c. These results are a reflex of the epidemiological features of HIV-1/HTLV-1/2 coinfection in the North region of Brazil, which is distinct from other Brazilian regions, as reported by previous studies.


Assuntos
Humanos , Masculino , Feminino , Infecções por HIV/complicações , HIV-1 , Infecções por HTLV-I/epidemiologia , Infecções por HTLV-II/epidemiologia , Vírus Linfotrópico T Tipo 1 Humano/genética , /genética , Doadores de Sangue , Brasil/epidemiologia , Ensaio de Imunoadsorção Enzimática , Anticorpos Anti-HTLV-I/sangue , Infecções por HTLV-I/complicações , Infecções por HTLV-I/virologia , Anticorpos Anti-HTLV-II/sangue , Infecções por HTLV-II/complicações , Infecções por HTLV-II/virologia , Filogenia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Prevalência
15.
Talanta ; 50(2): 247-52, 1999 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-18967714

RESUMO

Insertion of an electrochemical cell in a flow injection system to evaluate the on-line reduction of ionic species is presented. The cell comprised Pt electrodes installed in two sections separated by a Nafion membrane. The sample was injected into an acidic carrier stream and passed through the cathode compartment of the electrolytic chamber where the species were reduced as consequence of an applied DC voltage. The sample solution leaving the cell received a confluent reagent stream (1,10-phenanthroline buffered at pH 4.7) and the reacted products were dropped off in an open tube for gas/liquid separation. Efficiency of the Fe(3+) to Fe(2+) reduction in acidic medium was evaluated in the presence of strongly reducing species of V and Mo by monitoring the Fe(II) colored complex. Interferences from Pb(2+), Co(2+), Ni(2+), Zn(2+), Cu(2+), V(5+) and Mo(6+) were evaluated. Production of strongly reducing species of V at the electrolytic cell presented higher efficiency for Fe reduction than the electrolytic chamber itself. Total reduction of Fe(3+) in solutions containing up to 10 mg l(-1) Fe plus 100 mg l(-1) V or 100 mg l(-1) of Mo was achieved by the electrolytic process at 2 A. The quantitative determination of Fe and V in low silicon Fe/V alloys was achieved. Accuracy was assessed with the certified Euro-standard 577-1 ferrovanadium alloy produced by the Bureau of Analysed Samples Limited and no difference at the 95% confident level was found.

16.
Med. HUPE-UERJ ; 2(1): 63-72, 1983.
Artigo em Português | LILACS | ID: lil-15593
17.
J. bras. med ; 44(3): 28-35, passim, 1983.
Artigo em Português | LILACS | ID: lil-15706
18.
J. bras. med ; 43(6): 41-6, passim, 1982.
Artigo em Português | LILACS | ID: lil-12858
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