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1.
Chemosphere ; 183: 242-251, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28550781

RESUMO

The electrochemical behavior of different carbon-based electrodes with and without nanoparticles of platinum electrochemically dispersed on their surface has been studied. Among others, reduced graphene oxide based electrodes was used to determine the best conditions for the decolorization/degradation of the reactive dye C.I. Reactive Orange 4 in sulfuric medium. Firstly, the electrochemical behavior was evaluated by cyclic voltammetry. Secondly, different electrolyses were performed using two cell configurations: cell with anodic and cathodic compartments separated (divided configuration) and without any separation (undivided configuration). The best results were obtained when reduced graphene oxide based anodes were used. The degree of decolorization was monitored by spectroscopic methods and high performance liquid chromatography. It was found that all of them followed pseudo-first order kinetics. When reduced graphene oxide-based electrodes coated with dispersed platinum by alternate current methods electrodes were used, the lowest energy consumption and the higher decolorization kinetics rate were obtained. Scanning Electronic Microscopy was used to observe the morphological surface differences.


Assuntos
Técnicas Eletroquímicas/métodos , Grafite/química , Platina/química , Triazinas/análise , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Eletrodos , Eletrólise , Nanopartículas/química , Óxidos/química
2.
J Hazard Mater ; 172(1): 187-95, 2009 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-19647934

RESUMO

Synthetic solutions of hydrolysed C.I. Reactive Orange 4, a monoazo textile dye commercially named Procion Orange MX-2R (PMX2R) and colour index number C.I. 18260, was exposed to electrochemical treatment under galvanostatic conditions and Na2SO4 as electrolyte. The influence of the electrochemical process as well as the applied current density was evaluated. Ti/SnO2-Sb-Pt and stainless steel electrodes were used as anode and cathode, respectively, and the intermediates generated on the cathode during electrochemical reduction were investigated. Aliquots of the solutions treated were analysed by UV-visible and FTIR-ATR spectroscopy confirming the presence of aromatic structures in solution when an electro-reduction was carried out. Electro-oxidation degraded both the azo group and aromatic structures. HPLC measures revealed that all processes followed pseudo-first order kinetics and decolourisation rates showed a considerable dependency on the applied current density. CV experiments and XPS analyses were carried out to study the behaviour of both PMX2R and intermediates and to analyse the state of the cathode after the electrochemical reduction, respectively. It was observed the presence of a main intermediate in solution after an electrochemical reduction whose chemical structure is similar to 2-amino-1,5-naphthalenedisulphonic acid. Moreover, the analysis of the cathode surface after electrochemical reduction reveals the presence of a coating layer with organic nature.


Assuntos
Compostos Azo/química , Eletroquímica/métodos , Oxigênio/química , Sulfatos/química , Ésteres do Ácido Sulfúrico/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Cromatografia Líquida de Alta Pressão , Concentração de Íons de Hidrogênio , Resíduos Industriais , Soluções , Espectrofotometria Ultravioleta/métodos , Espectroscopia de Infravermelho com Transformada de Fourier , Aço Inoxidável , Têxteis , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química
3.
Chemosphere ; 75(10): 1329-37, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19345978

RESUMO

The electrochemical treatment of wastewaters from textile industry is a promising treatment technique for substances which are resistant to biodegradation. This paper presents the results of the electrochemical decolourisation and degradation of C.I. Reactive Orange 4 synthetic solutions (commercially known as Procion Orange MX2R). Electrolyses were carried out under galvanostatic conditions in a divided or undivided electrolytic cell. Therefore, oxidation, reduction or oxido-reduction experiences were tested. Ti/SnO(2)-Sb-Pt and stainless steel electrodes were used as anode and cathode, respectively. Degradation of the dye was followed by TOC, total nitrogen, COD and BOD(5) analyses. TOC removal after an oxidation process was higher than after oxido-reduction while COD removal after this last process was about 90%. Besides, the biodegradability of final samples after oxido-reduction process was studied and an improvement was observed. UV-Visible spectra revealed the presence of aromatic structures in solution when an electro-reduction was carried out while oxido-reduction process degraded both azo group and aromatic structures. HPLC analyses indicated the presence of a main intermediate after the reduction process with a chemical structure closely similar to 2-amine-1, 5-naphthalenedisulfonic acid. The lowest decolourisation rate corresponded to electrochemical oxidation. In these experiences a higher number of intermediates were generated as HPLC analysis demonstrated. The decolourisation process for the three electrochemical processes studied presented a pseudo-first order kinetics.


Assuntos
Corantes/química , Eletroquímica/métodos , Recuperação e Remediação Ambiental/métodos , Triazinas/química , Eletrodos , Cinética , Oxirredução , Indústria Têxtil , Eliminação de Resíduos Líquidos/métodos
4.
Genes Immun ; 3 Suppl 1: S57-62, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12215904

RESUMO

Renal disease occurs in 40-75% of systemic lupus erythematosus (SLE) patients and significantly contributes to morbidity and mortality. We used two pedigree stratification strategies to explore the impact of the ACR renal criterion for SLE classification upon genetic linkage with SLE. In both we used SLE as the phenotype. First, we evaluated genome scan data from >300 microsatellite markers in the 75 pedigrees that had at least one SLE affected with the SLE renal criterion. A maximum-likelihood parametric model approach produced a maximum screening LOD score of 3.16 at 10q22.3 in the European-American (EA) pedigrees. The African-American (AA) pedigrees obtained a maximum screening LOD score of 2.58 at 11p15.6. A multipoint sib-pair regression analysis produced P = 0.0000008 in EA at 10q22.3 (SLEN1) and P = 0.000001 in AA at 2q34-35 (SLEN2). A second stratification strategy explored the renal criterion in 35 pedigrees with two or more SLE patients with renal disease and produced a LOD score of 3.34 at 11p15.6 in AA (SLEN3). Sib-pair analysis in these 35 pedigrees revealed P = 0.00003 at 4q13.1 in EA, P = 0.00003 at 11p13 and 0.00007 at 3q23 in AA. Thus, multiple genetic linkages are related to the renal criterion in SLE. Of the significant genetic linkages with SLE described herein, those at 10q22.3 in the EA pedigrees (SLEN1) and at 2q34-35 in the AA pedigrees (SLEN2) have not been previously described.


Assuntos
Ligação Genética , Lúpus Eritematoso Sistêmico/genética , Nefrite/genética , População Negra/genética , Cromossomos Humanos Par 10 , Cromossomos Humanos Par 11 , Cromossomos Humanos Par 2 , Feminino , Humanos , Escore Lod , Masculino , Linhagem , População Branca/genética
5.
Cell Mol Biol (Noisy-le-grand) ; 47(7): 1223-7, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11838971

RESUMO

The serologic and clinical features of patients from pedigrees multiplex for systemic lupus erythematosus (SLE) were evaluated among three ethnic groups: Hispanics, African-Americans and European-Americans. Data were obtained from a registry of 123 pedigrees, composed of 4 Hispanic, 40 African-American and 79 European-American pedigrees. All patients met at least four criteria for the diagnosis of SLE per the American College of Rheumatology. Clinical information was obtained through review of the medical records and questionnaires completed by the participants. Ethnicity by self-identification was found to be an important factor influencing the prevalence of serologic results and clinical features. Anti-nRNP occurred more frequently in African-Americans (45.7%) than in European-Americans (7.5%) or Hispanics (0%) (p<0.0000001), as did anti-Sm (18.5% vs 1.6% and 0%, respectively) (p<0.000001). Malar rash, photosensitivity and oral ulcers were most frequent in the Hispanic population while proteinuria and leukopenia predominated in the African-American population. Arthritis and lymphopenia were present in a similar proportion in all ethnic groups. These results show that many of the ethnic differences known for isolated cases of SLE are also present in familial cases of SLE.


Assuntos
Etnicidade , Lúpus Eritematoso Sistêmico/imunologia , Lúpus Eritematoso Sistêmico/patologia , Adulto , Negro ou Afro-Americano , População Negra , Europa (Continente)/etnologia , Feminino , Hispânico ou Latino , Humanos , Lúpus Eritematoso Sistêmico/etnologia , Masculino , Linhagem , População Branca
6.
J Child Neurol ; 15(12): 803-7, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11198495

RESUMO

Neurologic complications of systemic lupus cerebritis are not as well known in children as in adults. Twenty-five children with neurologic complications were identified after reviewing the hospital medical records of 86 children with systemic lupus erythematosus. Seven children (28%) had neurologic symptoms at the time of initial diagnosis of systemic lupus erythematosus; median time between diagnosis of systemic lupus erythematosus and onset of neurologic complications was 1 month (range 0-5 years). Seizures were the most common neurologic symptoms overall, but headaches were the most frequent neurologic manifestation in children without a previous diagnosis of systemic lupus erythematosus. Sixteen children had seizures, and 12 children had seizures as the initial central nervous system involvement. Almost all children who developed seizures had an established diagnosis of systemic lupus erythematosus; only one child had seizures that led to the diagnosis of systemic lupus erythematosus. No patient had status epilepticus, and, in general, seizures were not difficult to control. In six children, headache was the initial symptom of central nervous system involvement. Five children had lupus cerebritis, three children had stroke, and two had isolated cranial neuropathies. Chorea was seen in only two cases, and three children had pseudotumor cerebri. Treatment with high-dose intravenous methylprednisolone led to a good response in 18 children; cyclophosphamide was required in 6 patients and plasmapheresis in 1 child. Outcome was generally good, although one child developed fulminant cerebritis with intracranial hypertension and died.


Assuntos
Lúpus Eritematoso Sistêmico/complicações , Doenças do Sistema Nervoso/etiologia , Convulsões/etiologia , Adolescente , Idade de Início , Criança , Ciclofosfamida/uso terapêutico , Evolução Fatal , Feminino , Cefaleia/etiologia , Humanos , Imunossupressores/uso terapêutico , Hipertensão Intracraniana/etiologia , Masculino , Metilprednisolona/uso terapêutico , Doenças do Sistema Nervoso/patologia , Doenças do Sistema Nervoso/terapia , Prognóstico , Estudos Retrospectivos
7.
Clin Exp Rheumatol ; 15(4): 445-8, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9272309

RESUMO

An 18-month-old Caucasian female began with a high fever. She developed swelling in one finger and one toe. Abdominal ultrasound revealed multiple abscesses in her spleen. Multiple blood culture and splenic abscess aspirations grew no pathogens. She had transient response to multiple antibiotics and splenic abscess drainage, but fever returned along with subcutaneous nodules. Culture of splenic tissue from her second splenic drainage eventually grew one organism identified as Actinomyces naeslundii. Therapy with high dose penicillin followed by amoxicillin p.o. and total splenectomy led to complete recovery.


Assuntos
Abscesso/microbiologia , Actinomyces/isolamento & purificação , Actinomicose/microbiologia , Artrite Reativa/microbiologia , Esplenopatias/microbiologia , Abscesso/diagnóstico por imagem , Abscesso/tratamento farmacológico , Actinomicose/diagnóstico por imagem , Actinomicose/tratamento farmacológico , Antibacterianos/uso terapêutico , Artrite Reativa/diagnóstico por imagem , Artrite Reativa/tratamento farmacológico , Diagnóstico Diferencial , Feminino , Humanos , Lactente , Penicilina G/uso terapêutico , Penicilinas/uso terapêutico , Baço/diagnóstico por imagem , Baço/microbiologia , Esplenopatias/diagnóstico por imagem , Esplenopatias/tratamento farmacológico , Tomografia Computadorizada por Raios X , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico
8.
Bol. Asoc. Méd. P. R ; 89(1/3): 12-14, Jan.-Mar. 1997.
Artigo em Inglês | LILACS | ID: lil-411479

RESUMO

Motor vehicle accidents are the main cause of death and disability between 1 and 4 years of age. Since 1980 the Academy of Pediatrics has been promoting the correct use of car seats. The major reason that car seats are not fulfilling their full potential is their incorrect or lack of use. In order to evaluate parental knowledge about car seat use for children and their actual use in the population visiting HURRA, a survey was performed which demonstrated that only 57.6 of the parents interviewed had infant car seats and that only 83.3 of owners actually use it. As many as 94.4 had correct knowledge about car seat use, but the majority of correct information was not provided by the medical staff. The majority of parents use seat belts for their own protection but a significantly smaller percentage use car seats for their own children


Assuntos
Humanos , Masculino , Feminino , Recém-Nascido , Lactente , Pré-Escolar , Pais/psicologia , Avaliação de Programas e Projetos de Saúde , Conhecimentos, Atitudes e Prática em Saúde , Inquéritos Epidemiológicos , Porto Rico , Pais/educação
10.
Bol Asoc Med P R ; 89(1-3): 12-4, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9168630

RESUMO

Motor vehicle accidents are the main cause of death and disability between 1 and 4 years of age. Since 1980 the Academy of Pediatrics has been promoting the correct use of car seats. The major reason that car seats are not fulfilling their full potential is their incorrect or lack of use. In order to evaluate parental knowledge about car seat use for children and their actual use in the population visiting HURRA, a survey was performed which demonstrated that only 57.6% of the parents interviewed had infant car seats and that only 83.3% of owners actually use it. As many as 94.4% had correct knowledge about car seat use, but the majority of correct information was not provided by the medical staff. The majority of parents use seat belts for their own protection but a significantly smaller percentage use car seats for their own children.


Assuntos
Equipamentos para Lactente , Pais/psicologia , Pré-Escolar , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Inquéritos Epidemiológicos , Humanos , Lactente , Equipamentos para Lactente/estatística & dados numéricos , Recém-Nascido , Masculino , Pais/educação , Avaliação de Programas e Projetos de Saúde , Porto Rico
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