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1.
Sci Total Environ ; 542(Pt A): 93-101, 2016 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-26519570

RESUMEN

It has been recognized that numerous synthetic compounds like Bisphenol A (BPA) and nonylphenols (NP) are present in effluents from wastewater treatment plants (WWTP) at levels of parts per billion (µg L(-1)) or even parts per trillion (ng L(-1)) with a high potential to cause endocrine disruption in the aquatic environment. Constructed wetlands (CW) are a cost-effective wastewater treatment alternative with promising performance to treat these afore mentioned compounds. This research was aimed to evaluate the efficacy of CW treatment of WWTP effluent for mitigating the effects endocrine disrupting compounds (EDCs). This research goal was accomplished by (1) quantifying the removal of BPA and NP in CWs; (2) isolating CW fungal strains and testing for laccase production; and (3) performing endocrine disruption (reproduction) bioassays using the fruit fly Drosophila melanogaster. Three pilot scale horizontal subsurface flow constructed wetlands (HSSF-CW) were operated for eight weeks: one planted with Phragmites australis; one planted with Heliconia psitacorum; and one unplanted. The Heliconia CW showed a removal efficiency of 73.3(± 19%) and 62.8(± 20.1%) for BPA and NP, respectively; while the Phragmites CW demonstrated a similar removal for BPA (70.2 ± 27%) and lower removal efficiency for NP 52.1(± 37.1%).The unplanted CW achieved 62.2 (± 33%) removal for BPA and 25.3(± 37%) removal for NP. Four of the eleven fungal strains isolated from the Heliconia-CW showed the capacity to produce laccase. Even though complete removal of EDCs was not achieved by the CWs, the bioassay confirmed a significant improvement (p < 0.05) in fly viability for all CWs, with Heliconia sp. being the most effective at mitigating adverse effects on first and second generational reproduction. This study showed that a CW planted with a native Heliconia sp. CW demonstrated a higher removal of endocrine disrupting compounds and better mitigation of reproductive disruption in the bioassay.


Asunto(s)
Compuestos de Bencidrilo/análisis , Fenoles/análisis , Eliminación de Residuos Líquidos/métodos , Aguas Residuales/química , Contaminantes Químicos del Agua/análisis , Humedales
2.
Int J Phytoremediation ; 17(1-6): 16-24, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25174421

RESUMEN

This study assessed the accumulation of Cd (II), Hg (II), Cr (VI) and Pb (II) in Gynerium sagittatum (Gs), Colocasia esculenta (Ce) and Heliconia psittacorum (He) planted in constructed wetlands treating synthetic landfill leachate. Sixteen bioreactors were operated in two experimental blocks. Metal concentrations in the influent and effluent; root, stem, branch and leaves of plants were analysed, as well as COD, N-NH4+, TKN, T, pH, ORP, DO, and EC. Average removal efficiencies of COD, TKN and NH4+-N were 66, 67 and 72%, respectively and heavy metal removal ranged from 92 to 98% in all units. Cr (VI) was not detected in any effluent sample. The bioconcentration factors (BCF) were 10(0) -10(2). The BCF of Cr (VI) was the lowest: 0.59 and 2.5 (L kg(-1)) for Gs and He respectively; whilst Cd (II) had the highest (130-135 L kg(-1)) for Gs. Roots showed a higher metal content than shoots. Translocation factors (TF) were lower, He was the plant exhibiting TFs>1 for Pb (II), Cr (T) and Hg (II) and 0.4-0.9 for Cd (II) and Cr (VI). The evaluated plants demonstrate their suitability for phytoremediation of landfill leachate and all of them can be categorized as metals accumulators.


Asunto(s)
Colocasia/metabolismo , Restauración y Remediación Ambiental/métodos , Heliconiaceae/metabolismo , Metales Pesados/metabolismo , Poaceae/metabolismo , Contaminantes Químicos del Agua/metabolismo , Biodegradación Ambiental , Colocasia/química , Heliconiaceae/química , Metales Pesados/análisis , Poaceae/química , Contaminantes Químicos del Agua/análisis , Humedales
3.
Environ Sci Pollut Res Int ; 22(17): 12804-15, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25253061

RESUMEN

Four subsurface horizontal-flow constructed wetlands (CWs) at a pilot scale planted with a polyculture of the tropical plants Gynerium sagittatum (Gs), Colocasia esculenta (Ce) and Heliconia psittacorum (He) were evaluated for 7 months. The CW cells with an area of 17.94 m(2) and 0.60 m (h) each and 0.5 m of gravel were operated at continuous gravity flow (Q = 0.5 m(3) day(-1)) and a theoretical HRT of 7 days each and treating landfill leachate for the removal of filtered chemical oxygen demand (CODf), BOD5, TKN, NH4 (+), NO3 (-), PO4 (3-)-P and Cr(VI). Three CWs were divided into three sections, and each section (5.98 m(2)) was seeded with 36 cuttings of each species (plant density of six cuttings per square metre). The other unit was planted randomly. The final distributions of plants in the bioreactors were as follows: CW I (He-Ce-Gs), CW II (randomly), CW III (Ce-Gs-He) and CW IV (Gs-He-Ce). The units received effluent from a high-rate anaerobic pond (BLAAT®). The results show a slightly alkaline and anoxic environment in the solid-liquid matrix (pH = 8.0; 0.5-2 mg L(-1) dissolved oxygen (DO)). CODf removal was 67 %, BOD5 80 %, and TKN and NH4 (+) 50-57 %; NO3 (-) effluents were slightly higher than the influent, PO4 (3-)-P (38 %) and Cr(VI) between 50 and 58 %. CW IV gave the best performance, indicating that plant distribution may affect the removal capacity of the bioreactors. He and Gs were the plants exhibiting a translocation factor (TF) of Cr(VI) >1. The evaluated plants demonstrated their suitability for phytoremediation of landfill leachate, and all of them can be categorized as Cr(VI) accumulators. The CWs also showed that they could be a low-cost operation as a secondary system for treatment of intermediated landfill leachate (LL).


Asunto(s)
Cromo/aislamiento & purificación , Contaminantes Químicos del Agua/aislamiento & purificación , Humedales , Biodegradación Ambiental , Análisis de la Demanda Biológica de Oxígeno , Cromo/metabolismo , Colocasia/metabolismo , Heliconiaceae/metabolismo , Nitrógeno/análisis , Proyectos Piloto , Poaceae/metabolismo , Clima Tropical , Instalaciones de Eliminación de Residuos , Contaminantes Químicos del Agua/metabolismo
4.
Water Sci Technol ; 70(3): 450-6, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25098874

RESUMEN

The potential of enhancing water uses using soil aquifer treatment (SAT) is an interesting alternative for tropical regions, limited only by lack of knowledge on its performance in local conditions and the feasibility of adapting this technology. A SAT pilot study was conducted to analyze the phenomena associated with the transformation of organic matter (OM) from domestic wastewater. Chemically enhanced primary effluent collected at the Cañaveralejo wastewater treatment plant (Cali, Colombia) was used to feed pilot-scale SAT units at a rate of 1.25 m.d⁻¹. Dissolved organic carbon (DOC) removal in a 5.0 m length and 0.1 m diameter column packed with sand was 64.4%, while a similar column packed with a Mollisol soil from Valle del Cauca region yielded 56.2%. Oxygen availability was an important factor in OM degradation, given that the sand column degraded OM aerobically and the soil column degraded OM under oxic as well as anoxic conditions. SAT acted as a reliable barrier for DOC in tropical conditions. Nevertheless, operational problems such as clogging indicated that probably Mollisol soil may not be the suitable for SAT or that this particular effluent requires further pre-treatment before SAT.


Asunto(s)
Agua Subterránea , Compuestos Orgánicos/aislamiento & purificación , Clima Tropical , Aguas Residuales , Purificación del Agua/métodos , Proyectos Piloto
5.
Tissue Antigens ; 66(6): 640-9, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16305680

RESUMEN

In order to characterize immunoglobulin heavy-chain variable (IGHV) genes in Aotus nancymaae monkeys, different mRNAs encoded by five IGHV families in this non-human primate were molecularly analysed considering their paramount importance in antibody production in an immune response. This study reports gene products exhibiting 91% amino acid similarity with IGHV1, IGHV2, IGHV3, IGHV4 and IGHV7 human IGHV families. Our analyses suggest that the IGHV gene has several conserved characteristics in humans and A. nancymaae. Several amino acid residues that are highly conserved in all family members described in humans were also present in these families in A. nancymaae. Antibody diversity in these families has remained the same since divergence of both species. Our study continues to provide evidence supporting the use of A. nancymaae monkey as an animal model for studying antibody response.


Asunto(s)
Aotidae/genética , Genes de Inmunoglobulinas , Cadenas Pesadas de Inmunoglobulina/genética , Región Variable de Inmunoglobulina/genética , Secuencia de Aminoácidos , Animales , Diversidad de Anticuerpos/genética , Aotidae/inmunología , Clonación Molecular , Humanos , Datos de Secuencia Molecular , Familia de Multigenes , Filogenia , Reacción en Cadena de la Polimerasa , ARN Mensajero/genética , ARN Mensajero/metabolismo , Homología de Secuencia de Aminoácido
6.
Infect Immun ; 63(11): 4301-6, 1995 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7591062

RESUMEN

Species-specific proteins may be implicated in the unique pathogenic mechanisms characteristic of Mycobacterium tuberculosis. In previous studies, a 3.0-kb species-specific DNA fragment of M. tuberculosis was identified (C. A. Parra, L. P. Londoño, P. del Portillo, and M. E. Patarroyo, Immun. 59:3411-3417, 1991). The nucleotide sequence of this 3.0-kb fragment has been obtained. This sequence was shown to contain two open reading frames (ORFs) whose putative gene products share 68.9% identity between each other. The major ORF shows 57.8% similarity with PLC-N and 53.2% similarity with PLC-H, two phospholipase C enzymes from Pseudomonas aeruginosa. The major ORF was amplified by PCR and cloned into the pGEX-5T expression vector. Cell extracts of Escherichia coli overexpressing this glutathione S-transferase fusion protein were shown to produce beta-hemolysis suggestive of phospholipase activity. Since phospholipase C enzymes have been reported as virulence factors of P. aeruginosa and also of the intracellular pathogen Listeria monocytogenes, it is possible that the proteins identified in this study could also play a role in sustaining tuberculosis infection in humans.


Asunto(s)
Genes Bacterianos/genética , Proteínas Hemolisinas/genética , Mycobacterium tuberculosis/genética , Fosfolipasas de Tipo C/genética , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , Cartilla de ADN/química , ADN Bacteriano/genética , Datos de Secuencia Molecular , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Especificidad de la Especie
7.
Rev. argent. dermatol ; 76(2): 73-5, abr.-jun. 1995. ilus
Artículo en Español | BINACIS | ID: bin-23957

RESUMEN

Presentamos una paciente de 11 meses de edad con un nevo lipomatoso cutáneo superficial en el brazo derecho.El cuadro clínico histopatológico es característico,pero de muy rara localización.Además de las manifestaciones cutáneas clásicas de la enfermedad,presentaba anomalías no descriptas previamente en la literatura,tales como:manchas mongólicas aberrantes,quistes gingivales y dientes natales.Se realiza una revisión de las diferentes variedades clínicas de nevo lipomatoso,diagnóstico diferencial e histiogénesis(AU)


Asunto(s)
Humanos , Femenino , Lactante , Nevo/diagnóstico , Brazo/patología , Hamartoma , Diagnóstico Diferencial , Anomalías de la Boca , Tejido Adiposo , Manifestaciones Cutáneas
8.
Rev. argent. dermatol ; 76(2): 80-1, abr.-jun. 1995. ilus
Artículo en Español | BINACIS | ID: bin-23955

RESUMEN

Presentamos el caso de una niña con argiria localizada en el lóbulo de la oreja, debida a la implantación de la tuerca de un aro de plata(AU)


Asunto(s)
Humanos , Femenino , Preescolar , Argiria/complicaciones , Argiria/diagnóstico , Plata/toxicidad
9.
Rev. argent. dermatol ; 76(2): 86-9, abr.-jun. 1995. ilus
Artículo en Español | BINACIS | ID: bin-23953

RESUMEN

Presentamos dos pacientes con manifestaciones extensas de liquen plano actínico pigmentario. Se revisa la literatura sobre el liquen actínico y sus variantes clínicas,destacando la inusual extensión observada en nuestros pacientes(AU)


Asunto(s)
Humanos , Masculino , Femenino , Persona de Mediana Edad , Liquen Plano/diagnóstico , Liquen Plano/terapia , Cara/patología , Cuello/patología , Corticoesteroides/uso terapéutico
10.
Rev. argent. dermatol ; 76(2): 97-9, abr.-jun. 1995. tab, ilus
Artículo en Español | BINACIS | ID: bin-23950

RESUMEN

Presentamos dos pacientes con carcinoma espinocelular ubicado sobre lesiones de liquen plano oral de larga evolución. Se discute la posibilidad de transformación maligna del liquen plano oral(AU)


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Anciano , Liquen Plano/etiología , Carcinoma/complicaciones , Neoplasias de la Boca/diagnóstico , Lengua/patología
11.
Rev. argent. dermatol ; 76(2): 73-5, abr.-jun. 1995. ilus
Artículo en Español | LILACS | ID: lil-147386

RESUMEN

Presentamos una paciente de 11 meses de edad con un nevo lipomatoso cutáneo superficial en el brazo derecho.El cuadro clínico histopatológico es característico,pero de muy rara localización.Además de las manifestaciones cutáneas clásicas de la enfermedad,presentaba anomalías no descriptas previamente en la literatura,tales como:manchas mongólicas aberrantes,quistes gingivales y dientes natales.Se realiza una revisión de las diferentes variedades clínicas de nevo lipomatoso,diagnóstico diferencial e histiogénesis


Asunto(s)
Humanos , Femenino , Lactante , Brazo/patología , Diagnóstico Diferencial , Hamartoma , Anomalías de la Boca , Nevo/diagnóstico , Tejido Adiposo , Manifestaciones Cutáneas
12.
Rev. argent. dermatol ; 76(2): 80-1, abr.-jun. 1995. ilus
Artículo en Español | LILACS | ID: lil-147388

RESUMEN

Presentamos el caso de una niña con argiria localizada en el lóbulo de la oreja, debida a la implantación de la tuerca de un aro de plata


Asunto(s)
Humanos , Femenino , Preescolar , Argiria/complicaciones , Argiria/diagnóstico , Plata/toxicidad
13.
Rev. argent. dermatol ; 76(2): 86-9, abr.-jun. 1995. ilus
Artículo en Español | LILACS | ID: lil-147390

RESUMEN

Presentamos dos pacientes con manifestaciones extensas de liquen plano actínico pigmentario. Se revisa la literatura sobre el liquen actínico y sus variantes clínicas,destacando la inusual extensión observada en nuestros pacientes


Asunto(s)
Humanos , Masculino , Femenino , Persona de Mediana Edad , Cara/patología , Liquen Plano/diagnóstico , Liquen Plano/terapia , Cuello/patología , Corticoesteroides/uso terapéutico
14.
Rev. argent. dermatol ; 76(2): 97-9, abr.-jun. 1995. tab, ilus
Artículo en Español | LILACS | ID: lil-147393

RESUMEN

Presentamos dos pacientes con carcinoma espinocelular ubicado sobre lesiones de liquen plano oral de larga evolución. Se discute la posibilidad de transformación maligna del liquen plano oral


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Anciano , Carcinoma/complicaciones , Liquen Plano/etiología , Neoplasias de la Boca/diagnóstico , Lengua/patología
15.
Infect Immun ; 59(10): 3411-7, 1991 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1909999

RESUMEN

A rabbit polyclonal antiserum exhibiting a specific recognition pattern for Mycobacterium tuberculosis proteins was used to screen an M. tuberculosis genomic library constructed in the expression vector lambda gt11. One clone, denominated C1:10, expressed M. tuberculosis-specific determinants as part of a large fusion protein with beta-galactosidase. The gene for this protein has been sequenced, and it encodes a protein of 134 amino acids (13.8 kDa) which did not display significant homology with any of the previously reported proteins in the data bases. Hybridization studies with restriction fragments of the cloned sequence revealed that it was not present in the genomes of related mycobacteria, namely, M. bovis, M. bovis BCG, M. flavescens, M. fortuitum, M. phlei, and M. vaccae. These findings suggest that we have detected a gene, or a fragment therefrom, unique for M. tuberculosis whose nucleotide and amino acid sequences could be useful tools in the design of an improved vaccine or a diagnostic method of greater accuracy for tuberculosis.


Asunto(s)
Antígenos Bacterianos/genética , Clonación Molecular , Genes Bacterianos , Mycobacterium tuberculosis/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Codón , Biblioteca de Genes , Sueros Inmunes/inmunología , Datos de Secuencia Molecular , Hibridación de Ácido Nucleico , Conejos , Especificidad de la Especie
16.
Infect Immun ; 59(7): 2265-73, 1991 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1711013

RESUMEN

Synthetic peptides derived from the amino acid sequence of MTP40, a recently characterized Mycobacterium tuberculosis protein, were tested by two different immunological assays in 91 individuals. For the purposes of this study, the population was distributed in four groups: active tuberculosis (TBC) patients with elevated bacillus loads (BK+), active TBC patients with low bacillus loads (BK-), healthy individuals living in the same household with tuberculous patients (HH), and normal individuals, who had presumably never been in contact with the bacilli (control). We found that T cells of individuals belonging to the HH group showed the highest and most frequent recognition of these peptides in a T-cell proliferation assay, while their antibodies showed the lowest recognition of these peptides when tested by enzyme-linked immunosorbent assay. In contrast, TBC patients revealed an inverse pattern of immune response. Interestingly, one of these peptides (P7) was recognized by T cells of 64% of the HH individuals and by 4.5% of normal donors. Another peptide (P4) was recognized by 55% of sera from BK+ patients and by 5.5% of normal donors. The results presented here indicate the existence of T- and B-cell epitopes within the MTP40 protein. Given the particular recognition pattern of this protein, added to the fact that it appears to be a species-specific antigen of M. tuberculosis, a detailed study of the immune response to it may be useful in the design of more accurate diagnostic tests and an improved vaccine against human TBC.


Asunto(s)
Antígenos Bacterianos/inmunología , Linfocitos B/inmunología , Proteínas Bacterianas , Mycobacterium tuberculosis/inmunología , Linfocitos T/inmunología , Fosfolipasas de Tipo C , Secuencia de Aminoácidos , Anticuerpos Antibacterianos/inmunología , Especificidad de Anticuerpos , Antígenos Bacterianos/química , Epítopos , Humanos , Activación de Linfocitos , Datos de Secuencia Molecular , Péptidos/química , Tuberculosis/inmunología
17.
Proc Natl Acad Sci U S A ; 86(8): 2799-803, 1989 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2468158

RESUMEN

The amino acid sequence of the amino-terminal half of the complement protein C6 has been found to show overall structural homology with the homologous regions of the channel-forming proteins C7, C8 alpha, C8 beta, and C9. In addition, two specific cysteine-rich segments common to the amino-terminal regions of C7, C8 alpha, C8 beta, and C9 also occur in their expected positions in C6, suggesting functional significance. Two cDNA clones encoding C6 were isolated from a human liver library in the bacteriophage vector lambda gt11. The predicted protein sequence contains an apparent initiation methionine and a putative signal peptide of 21 residues, as well as a site for N-glycosylation at residue 303. The sequence of the C6 protein reported here has 47-52% similarity with C7, C8 alpha, C8 beta, and C9, as well as 31-38% similarity with thrombospondin, thrombomodulin, and low density lipoprotein receptor. The sequence data have been interpreted by using computer algorithms for estimation of average hydrophobicity and secondary structure.


Asunto(s)
Complemento C6/ultraestructura , Proteínas del Sistema Complemento/genética , Canales Iónicos/ultraestructura , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , Complejo de Ataque a Membrana del Sistema Complemento , Cisteína , ADN/genética , Humanos , Sustancias Macromoleculares , Glicoproteínas de Membrana/ultraestructura , Datos de Secuencia Molecular , Conformación de Ácido Nucleico , Solubilidad
18.
Hautarzt ; 39(11): 750-2, 1988 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-3243719

RESUMEN

We report a patient with nail and bone disorders of the index and middle fingers (Iso and Kikuchi syndrome) associated with chronic discoid lupus erythematosus. Angiographic studies showed filiform arteries of the fingers and slow blood circulation. Since a vascular pathogenic mechanisms is probable, the designation "Congenital ischemic onychodystrophy" seems more suitable. The association with chronic discoid lupus erythematosus has not previously been reported.


Asunto(s)
Dedos/irrigación sanguínea , Isquemia/complicaciones , Lupus Eritematoso Discoide/complicaciones , Uñas Malformadas/complicaciones , Adulto , Angiografía , Humanos , Isquemia/congénito , Masculino , Uñas Malformadas/congénito
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