Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
1.
Chemosphere ; 250: 126248, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32092573

RESUMEN

Medium density fiberboard (MDF) wastes were converted into an efficient char able to uptake Food Red 17 dye (FR17) from colored effluents. The yield of the pyrolysis process, in terms of char, was 29%. The produced char presented micro and mesoporous, with surface area of 218.8 m2 g-1 and total pore volume of 0.122 cm3 g-1. Regarding to the FR17 adsorption, removal percentages of 90% were found at pH 2 and using 0.5 g L-1 of char. Pseudo-first and pseudo-second order models were adequate to represent the adsorption kinetic profile, being the equilibrium reached within 20 min. Freundlich model was selected to represent the equilibrium data. The maximum adsorption capacity was 210 mg g-1. The adsorption of FR17 on the char was endothermic and physical in nature. The char was efficient for 8 adsorption-desorption cycles, maintaining the same adsorption capacity. In brief, this work demonstrated a useful practice in terms of cleaner production. It was possible add value to MDF wastes, generating an efficient and reusable adsorbent to treat colored effluents containing FR 17 dye.


Asunto(s)
Compuestos Azo/química , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos , Adsorción , Colorantes , Concentración de Iones de Hidrógeno , Cinética , Pirólisis , Agua , Contaminantes Químicos del Agua/análisis
2.
Environ Geochem Health ; 42(9): 2771-2788, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31900823

RESUMEN

The chemical reactions of dry-disposed ash dump, ingressed oxygen, carbon dioxide, and infiltrating rainwater affect mineralogical transformation, redistribution, and migration of chemical species. Composite samples of weathered coal fly ash taken at various depths and fresh coal fly ash were examined using organic petrographic, X-ray diffraction, X-ray fluorescence techniques, and successive extraction procedures. Results obtained show relative enrichment of glass, Al-Fe-oxides, calcite, and tridymite in the weathered CFA, but the fresh CFA is enriched in mullite, inertinite, maghemite, and ettringite. The enrichment of the weathered CFA in amorphous glass suggests higher reactivity when compared to fresh CFA. The evident depletion of soluble oxides in the weathered CFA is attributed to flushing of the soluble salts by percolating rainwater. Comparative enrichment of examined elements in water-soluble, exchangeable, reducible, and residual fractions of the weathered CFA is partly due to the slow release of adsorbed chemical species from the alumina-silicate matrix and diffusion from the deeper sections of the particles of coal fly ash. Sodium and potassium show enrichment in the oxidisable fraction of fresh CFA. The estimated mobility factor indicates mobility for Ca, Mg, Na, Se, Mo, and Sb and K, Sr, V, Cu, Cr, Se, and B in fresh and weathered CFAs, respectively.


Asunto(s)
Ceniza del Carbón/química , Metales/análisis , Administración de Residuos/métodos , Dióxido de Carbono/química , Fraccionamiento Químico , Ceniza del Carbón/análisis , Metales/química , Suelo/química , Solubilidad , Sudáfrica , Espectrometría por Rayos X , Instalaciones de Eliminación de Residuos , Tiempo (Meteorología) , Difracción de Rayos X
3.
Clin Vaccine Immunol ; 18(11): 1823-33, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21900533

RESUMEN

Enteropathogenic Escherichia coli (EPEC) is a common cause of diarrhea in children from developing countries. Intimate adhesion of the bacteria to intestinal cells occurs via binding of the adhesin intimin to the TIR receptor exposed on cell surfaces. Here, Lactobacillus casei expressing a fragment of ß-intimin (L. casei-Int(cv)) was tested as mucosal vaccines in mice against intestinal colonization with the murine pathogen Citrobacter rodentium. Oral or sublingual immunization of C57BL/6 mice with L. casei-Int(cv) induced anti-Int(cv) IgA in feces but no IgG in sera. Conversely, anti-Int(cv) IgG was induced in the sera of mice after sublingual immunization with purified Int(cv). All vaccines were able to decrease C. rodentium recovery from feces. However, this reduction was more evident and sustained over time in mice immunized with L. casei-Int(cv) by the sublingual route. These mice also displayed an increase in interleukin 6 (IL-6) and gamma interferon (IFN-γ) secretion by spleen cells 10 days after infection. Additionally, oral or sublingual immunization of C3H/HePas mice, which are highly susceptible to C. rodentium infection, with L. casei-Int(cv) induced anti-Int(cv) antibodies and significantly increased survival after challenge. Immunohistological analysis of colon sections revealed that C. rodentium was located in deep fractions of the tissue from C3H/HePas mice immunized with L. casei whereas superficial staining was observed in colon sections from mice immunized with L. casei-Int(cv.) The results indicate that vaccines composed of L. casei expressing intimin may represent a promising approach and that the C3H/HePas infection model with C. rodentium can be used to evaluate potential vaccines against EPEC.


Asunto(s)
Adhesinas Bacterianas/inmunología , Vacunas Bacterianas/inmunología , Citrobacter rodentium/inmunología , Portadores de Fármacos , Infecciones por Enterobacteriaceae/prevención & control , Proteínas de Escherichia coli/inmunología , Vectores Genéticos , Lacticaseibacillus casei/genética , Adhesinas Bacterianas/genética , Administración Oral , Administración Sublingual , Animales , Anticuerpos Antibacterianos/sangre , Vacunas Bacterianas/administración & dosificación , Citrobacter rodentium/genética , Colon/patología , Infecciones por Enterobacteriaceae/inmunología , Infecciones por Enterobacteriaceae/microbiología , Infecciones por Enterobacteriaceae/mortalidad , Proteínas de Escherichia coli/genética , Heces/microbiología , Femenino , Humanos , Inmunización/métodos , Interferón gamma/metabolismo , Interleucina-6/metabolismo , Leucocitos Mononucleares/inmunología , Ratones , Ratones Endogámicos C3H , Ratones Endogámicos C57BL , Bazo/inmunología , Análisis de Supervivencia , Vacunas Sintéticas/administración & dosificación , Vacunas Sintéticas/inmunología
4.
Trans R Soc Trop Med Hyg ; 105(8): 473-8, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21684567

RESUMEN

The identification of appropriate laboratory measures to confirm clinical hypotheses is important in routine paracoccidioidomycosis medical care. The clinical records and laboratory reports of 401 paracoccidioidomycosis patients attended at the Tropical Diseases Area, Faculdade de Medicina de Botucatu, from 1974 to 2008 were reviewed. Direct mycological (DM), cell block (CB), histopathological (HP), and double immunodiffusion (DID) tests were evaluated before treatment. Typical Paracoccidioides brasiliensis yeast forms were observed in clinical specimens of 86% of the patients, but 14% were detected only by serological test. DM of 51 different tissue specimens produced 74.5% sensitivity, and 62.5% sensitivity was observed in 112 sputum samples. CB in 483 sputum samples generated 55.3% sensitivity. HP performed in 239 samples from different tissues revealed 96.7% sensitivity. Serology carried out in 351 patients and 200 healthy controls provided 90.0% sensitivity, 100.0% specificity, 100.0% positive predictive value, 85.1% negative predictive value and 93.6% accuracy. Comparisons of laboratory measurements performed in the same patient showed that sensitivity decreases from HP to DID to CB and DM, with the last two assays providing similar sensitivities. This study demonstrated that P. brasiliensis identification by HP, CB, and/or DM associated with DID is sufficient to establish the laboratorial diagnosis of paracoccidioidomycosis in practically all cases.


Asunto(s)
Inmunodifusión , Paracoccidioides/aislamiento & purificación , Paracoccidioidomicosis/inmunología , Esputo/inmunología , Adulto , Brasil/epidemiología , Pruebas Diagnósticas de Rutina , Femenino , Hospitales Universitarios , Humanos , Inmunodifusión/métodos , Masculino , Persona de Mediana Edad , Paracoccidioidomicosis/diagnóstico , Paracoccidioidomicosis/epidemiología , Estudios Retrospectivos
5.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;44(6): 500-513, June 2011. ilus, tab
Artículo en Inglés | LILACS, SES-SP | ID: lil-589971

RESUMEN

Aluminum salts have been widely used in vaccine formulations and, after their introduction more than 80 years ago, only few vaccine formulations using new adjuvants were developed in the last two decades. Recent advances in the understanding of how innate mechanisms influence the adaptive immunity opened up the possibility for the development of new adjuvants in a more rational design. The purpose of this review is to discuss the recent advances in this field regarding the attempts to determine the molecular basis and the general mechanisms underlying the development of new adjuvants, with particular emphasis on the activation of receptors of innate immune recognition. One can anticipate that the use of these novel adjuvants will also provide a window of opportunities for the development of new vaccines.


Asunto(s)
Animales , Humanos , Inmunidad Adaptativa/inmunología , Inmunidad Innata/inmunología , Receptores de Reconocimiento de Patrones/inmunología , Vacunas/inmunología , Factores de Virulencia/inmunología , Adyuvantes Inmunológicos/química , Compuestos de Aluminio/inmunología , Inmunidad Celular/inmunología , Vacuna contra la Tos Ferina/inmunología , Receptores Toll-Like/inmunología , Vacunas Atenuadas/inmunología , Vacunas/química
6.
Braz J Med Biol Res ; 44(6): 500-13, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21584443

RESUMEN

Aluminum salts have been widely used in vaccine formulations and, after their introduction more than 80 years ago, only few vaccine formulations using new adjuvants were developed in the last two decades. Recent advances in the understanding of how innate mechanisms influence the adaptive immunity opened up the possibility for the development of new adjuvants in a more rational design. The purpose of this review is to discuss the recent advances in this field regarding the attempts to determine the molecular basis and the general mechanisms underlying the development of new adjuvants, with particular emphasis on the activation of receptors of innate immune recognition. One can anticipate that the use of these novel adjuvants will also provide a window of opportunities for the development of new vaccines.


Asunto(s)
Inmunidad Adaptativa/inmunología , Inmunidad Innata/inmunología , Receptores de Reconocimiento de Patrones/inmunología , Vacunas/inmunología , Factores de Virulencia/inmunología , Adyuvantes Inmunológicos/química , Compuestos de Aluminio/inmunología , Animales , Humanos , Inmunidad Celular/inmunología , Vacuna contra la Tos Ferina/inmunología , Receptores Toll-Like/inmunología , Vacunas/química , Vacunas Atenuadas/inmunología
7.
Clin Vaccine Immunol ; 16(5): 636-45, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19279169

RESUMEN

Pneumococcal surface protein A (PspA) and PspC are virulence factors that are involved in the adhesion of Streptococcus pneumoniae to epithelial cells and/or evasion from the immune system. Here, the immune responses induced by mucosal vaccines composed of both antigens as recombinant proteins or delivered by Lactobacillus casei were evaluated. None of the PspC vaccines protected mice against an invasive challenge with pneumococcal strain ATCC 6303. On the other hand, protection was observed for immunization with vaccines composed of PspA from clade 5 (PspA5 or L. casei expressing PspA5) through the intranasal route. The protective response was distinguished by a Th1 profile with high levels of immunoglobulin G2a production, efficient complement deposition, release of proinflammatory cytokines, and infiltration of neutrophils. Intranasal immunization with PspA5 elicited the highest level of protection, characterized by increased levels of secretion of interleukin-17 and gamma interferon by lung and spleen cells, respectively, and low levels of tumor necrosis factor alpha in the respiratory tract.


Asunto(s)
Proteínas Bacterianas/inmunología , Vacunas Neumococicas/administración & dosificación , Vacunas Neumococicas/inmunología , Neumonía Neumocócica/prevención & control , Streptococcus pneumoniae/inmunología , Administración Intranasal , Animales , Anticuerpos Antibacterianos/inmunología , Proteínas Bacterianas/genética , Células Cultivadas , Citocinas/metabolismo , Femenino , Vectores Genéticos , Lacticaseibacillus casei/genética , Leucocitos Mononucleares/inmunología , Pulmón/inmunología , Ratones , Ratones Endogámicos C57BL , Datos de Secuencia Molecular , Neutrófilos/inmunología , Análisis de Secuencia de ADN , Bazo/inmunología , Vacunas Sintéticas/genética , Factores de Virulencia/inmunología
8.
Environ Geochem Health ; 31(4): 475-85, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18677575

RESUMEN

The current paper presents the concentration, distribution, and modes of occurrence of trace elements of 13 coals from south Brazil. The samples were collected in the state of Santa Catarina. Chemical analyses and the high ash yields indicate that all studied coals are rich in mineral matter, with SiO(2) and Al(2)O(3) dominating as determined by inductively coupled plasma-atomic emission spectrometry (ICP-AES). Quartz is the main mineral species and is associated with minor levels of feldspars, kaolinite, hematite, and iron-rich carbonates. The contents of trace elements, including As, Pb, Cd, Ni, Cr, Mn, Be, V, U, Zn, Li, Cu, Tl, and Ni, in coals were determined. A comparison of ranges and means of elemental concentrations in Santa Catarina, Brazil, and world coals shows that the ranges of most elements in Santa Catarina coal are very close to the usual worldwide concentration ranges in coal.


Asunto(s)
Carbón Mineral/análisis , Contaminantes Ambientales/análisis , Oligoelementos/análisis , Brasil , Carbono/química , Carbón Mineral/clasificación , Ceniza del Carbón , Minas de Carbón , Monitoreo del Ambiente , Humanos , Material Particulado/química
9.
Infect Immun ; 74(8): 4939-44, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16861686

RESUMEN

One of the candidate proteins for a mucosal vaccine antigen against Streptococcus pneumoniae is PsaA (pneumococcal surface antigen A). Vaccines targeting mucosal immunity may raise concerns as to possible alterations in the normal microbiota, especially in the case of PsaA, which was shown to have homologs with elevated sequence identity in other viridans group streptococci. In this work, we demonstrate that intranasal immunization with a cholera toxin B subunit-PsaA fusion protein is able to protect mice against colonization with S. pneumoniae but does not significantly alter the natural oral or nasopharyngeal microbiota of mice.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Proteínas Bacterianas/administración & dosificación , Toxina del Cólera/administración & dosificación , Vacunas Neumococicas/administración & dosificación , Proteínas Recombinantes de Fusión/administración & dosificación , Streptococcus pneumoniae/inmunología , Administración Intranasal , Animales , Proteínas Bacterianas/genética , Proteínas Bacterianas/inmunología , Proteínas Bacterianas/metabolismo , Toxina del Cólera/genética , Toxina del Cólera/inmunología , Toxina del Cólera/metabolismo , Femenino , Bacterias Grampositivas/crecimiento & desarrollo , Bacterias Grampositivas/aislamiento & purificación , Inmunización , Inmunoglobulina A/sangre , Inmunoglobulina G/sangre , Ratones , Ratones Endogámicos C57BL , Boca/microbiología , Nasofaringe/microbiología , Infecciones Neumocócicas/inmunología , Infecciones Neumocócicas/microbiología , Infecciones Neumocócicas/prevención & control , Vacunas Neumococicas/inmunología , Proteínas Recombinantes de Fusión/inmunología , Streptococcus pneumoniae/crecimiento & desarrollo
10.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;32(7): 861-5, July 1999.
Artículo en Inglés | LILACS | ID: lil-234892

RESUMEN

Polyomavirus is a DNA tumor virus that induces a variety of tumors in mice. Its genome encodes three proteins, namely large T (LT), middle T (MT), and small T (ST) antigens, that have been implicated in cell transformation and tumorigenesis. LT is associated with cell immortalization, whereas MT plays an essential role in cell transformation by binding to and activating several cytoplasmic proteins that participate in growth factor-induced mitogenic signal transduction to the nucleus. The use of different MT mutants has led to the identification of MT-binding proteins as well as analysis of their importance during cell transformation. Studying the molecular mechanisms of cell transformation by MT has contributed to a better understanding of cell cycle regulation and growth control


Asunto(s)
Humanos , Animales , Ratones , Antígenos Transformadores de Poliomavirus/genética , Transformación Celular Neoplásica/genética , Infecciones por Papillomavirus/genética , Poliomavirus/genética , Transducción de Señal/genética , Antígenos Transformadores de Poliomavirus/metabolismo , Transformación Celular Neoplásica/metabolismo , Mutación , Infecciones por Papillomavirus/metabolismo , Poliomavirus , Transducción de Señal , Transcripción Genética
11.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;29(9): 1133-40, Sept. 1996.
Artículo en Inglés | LILACS | ID: lil-186123

RESUMEN

Polyomavirus, a DNA tumor virus, expresses three viral oncoproteins (large, middle and small T antigens), causes malignant transformation in cell culture and induces multiple tumors in vivo. The middle T (MT) antigen seems to play an essential role in transformation and tumori-genicity. The observation that MT-overexpressing cell lines are able to grow in the absence of PDGF (platelet-derived growth factor) led several laboratories to study the mechanism underlying MT-induced growth deregulation and the signal transduction pathway used by this viral oncoprotein. A number of cellular proteins were shown to be common to both the normal PDGF mitogenic pathway and the MT transforming pathway. The expression of some PDGF primary response genes (fos, jun, myc, JE, KC) was shown to be rendered constitutive by MT overexpression. Using MT mutants, important domains for binding and activation of cytoplasmic proteins were mapped. Wild type and mutant MT cell lines are used in our laboratory to analyze the expression and activity of the PDGF early response genes during cell transformation and correlate them with activation of specific cytoplasmic proteins. In addition to abrogating the PDGF requirement for growth, activation of cellular proteins caused by MT results in cell lines that have an altered morphology and are able to form colonies in agarose. These changes may be due to alterations in connexin 43 and other cell surface proteins.


Asunto(s)
Humanos , Expresión Génica/inmunología , Factor de Crecimiento Derivado de Plaquetas/genética , Poliomavirus/genética , Virus Oncogénicos/genética , Poliomavirus/inmunología
12.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;29(7): 911-9, July 1996. ilus, tab
Artículo en Inglés | LILACS | ID: lil-181501

RESUMEN

A number of gene products involved in the control of cell proliferation fall into one of two classes: oncogenes and tumor suppressor genes. The same gene products have also been associated with malignant growth (tumors) caused by radiation, chemicals and tumor viruses. Here we describe our attempts to elucidate the molecular mechanisms underlying polyomavirus-induced cell transformation and the anti-tumor activity of glucocorticoid hormones. Wild type and mutant polyomavirus middle T (MT) overexpressing cell lines, generated with retroviral vector constructs, were used to investigate the role played by peptide growth factor primary response genes (fos, jun, myc, JE, KC) in viral transformation and to map the transduction pathway of the mitogenic signal of MT. Overexpression of MT leads to increased AP-1 (Fos/Jun) transcriptional complex activity. Transformation defective mutant analysis allowed the identification of sites in the MT molecule that are crucial for this activity. Two different approaches were used to investigate the molecular basis for glucocorticoids anti-tumor activity, namely: blind cloning of cDNAs and analysis of growth control genes in C6 glioma cell variants that are either hypersensitive (C6/ST1) or unresponsive to glucocorticoids (C6/P7). Four different glucocorticoid-regulated cDNA sequences were isolated using differential hybridization. A number of differentially expressed sequences were isolated from glucocorticoid-treated C6/ST1 cells by differential display (DDRT-PCR) and are currently being characterized. Expression of known growth control genes in C6/ST1 cells allowed the identification of important candidates for glucocorticoid hormone targets.


Asunto(s)
Animales , Ratas , ADN/genética , Genes Supresores de Tumor/genética , Oncogenes/genética , Poliomavirus/genética , ARN/genética , Transformación Celular Neoplásica/genética , Secuencia de Bases , Western Blotting , Clonación Molecular , División Celular/genética , ADN/aislamiento & purificación , Glucocorticoides/metabolismo , Sustancias de Crecimiento , Neoplasias/virología , Hibridación de Ácido Nucleico , Proteínas/fisiología , Factores de Transcripción , Activación Transcripcional
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA