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1.
Chemosphere ; 281: 130999, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34289637

ABSTRACT

Nowadays the study of the potential applications of multifunctional materials for environmental remediation is one of the main goals of the materials engineering. Multifunctional porous materials, MPMs, incorporate, all in once, different and multiple functionalities that make them suitable for several uses and can satisfy many purposes at the same time. Multifunctional diatomite-based foams with a hierarchical porosity, already produced and characterized to be applied in building as well as aerospace sectors, are proposed as adsorbents for inorganic and organic pollutants removal from wastewaters. Then, the effect of the addition of different carbonaceous nanofillers (graphite, graphene and graphene oxide) on the water purification efficiency of the adsorbent was evaluated. Firstly, pristine MPM showed the best performance in adsorbing Indigo Carmine due to its intrinsic chemism and hierarchical porosity (at macro-, micro- and nano-level), but it is not the best with respect to the Cd2+ adsorption, if compared with the nanocomposites. Among the nanocomposite products, both graphene- and graphene oxide-MPM samples showed a significantly improved adsorption capacity towards Cd2+. This behavior is due to the synergistic effect of the finer morphology, higher available foam surface, and the highly exfoliated fillers, graphene and graphene oxide, which permit a better dispersion into the matrix.


Subject(s)
Graphite , Nanocomposites , Water Pollutants, Chemical , Water Purification , Adsorption , Diatomaceous Earth , Water Pollutants, Chemical/analysis
2.
Carbohydr Polym ; 211: 195-203, 2019 May 01.
Article in English | MEDLINE | ID: mdl-30824079

ABSTRACT

Chitosan (CS) aerogels were prepared by freeze-drying as potential adsorbents for water purification, and the effect of the strategy of crosslinking was investigated by varying the amount of crosslinker (glutaraldehyde) and the sequence of steps for the preparation of the aerogel. Two procedures were compared, in which the crosslinking step was carried out before or after the freeze-drying of the starting CS solution. When crosslinking was postponed after the freeze-drying step, the adsorption capacity towards an anionic dye, such as indigo carmine, considerably increased (up to +45%), reaching values as high as 534.4 ± 30.5 mg g-1. The same crosslinking strategy ensured a comparable improvement also in nanocomposite aerogels containing graphene oxide (GO), which was added to enhance the mechanical strength and provide adsorption capacity towards cationic dyes. Besides possessing good mechanical strength (compressive modulus higher than 1 MPa), the CS/GO aerogels were able to bind also cationic pollutants such as methylene blue. The maximum uptake capacity increased from 4.3 ± 1.6 to 168.6 ± 9.6 mg of cationic dye adsorbed per gram of adsorbent with respect to pristine CS aerogels.

3.
Soft Matter ; 13(37): 6465-6473, 2017 Sep 27.
Article in English | MEDLINE | ID: mdl-28876350

ABSTRACT

The sequence of events which leads to the interfacial crowding of plate-like nanoparticles in co-continuous polymer blends is investigated through a combination of morphological and rheological analyses. Very low amounts (∼0.2 vol%) of organo-modified clay are sufficient to suppress phase coarsening in a co-continuous polystyrene/poly(methyl methacrylate) blend, while lower particle loading allows for a tuning of the characteristic size of the polymer phases at the µm-scale. In any case, an interfacial network of nanoparticles eventually forms, which is driven by the preferred polymer-polymer interface. The elastic features and stress-bearing ability of this peculiar nanoparticle assembly are studied in detail by means of a descriptive two-phase viscoelastic model, which allows isolation of the contribution of the filler network. The role of the co-continuous matrix in driving the space arrangement of the nanoparticles is emphasized by means of comparative analysis with systems based on the same polymers and nanoparticles, but in which the matrix is either a pure polymer or a blend with drop-in-matrix morphology. The relaxation dynamics of the interfacial network was found not to depend on the matrix microstructure, which instead substantially affects the assembly of the nanoplatelets. When the host medium is co-continuous, the particles align along the preferred polymer-polymer interface, percolating at a very low amount (∼0.17 vol%) and prevalently interacting edge-to-edge. The stress bearing ability of such a network is much higher than that in the case of matrix based on a homogeneous polymer or a drop-in-matrix blend, but its elasticity shows low sensitivity to the filler content.

4.
Water Sci Technol ; 63(4): 666-70, 2011.
Article in English | MEDLINE | ID: mdl-21330712

ABSTRACT

This study evaluated the efficiency of a shallow (0.5 m deep) waste stabilization pond series to remove high concentrations of ammonia from sanitary landfill leachate. The pond system was located at EXTRABES, Campina Grande, Paraiba, Northeast Brazil. The pond series was fed with sanitary landfill leachate transported by road tanker to the experimental site from the sanitary landfill of the City of Joao Pessoa, Paraiba. The ammoniacal-N surface loading on the first pond of the series was equivalent to 364 kg ha(-1) d(-1) and the COD surface loading equivalent to 3,690 kg ha(-1) d(-1). The maximum mean ammonia removal efficiency was 99.5% achieved by the third pond in the series which had an effluent concentration of 5.3 mg L(-1) ammoniacal-N for an accumulative HRT of 39.5 days. The removal process was mainly attributed to ammonia volatilization (stripping) from the pond surfaces as a result of high surface pH values and water temperatures of 22-26°C. Shallow pond systems would appear to be a promising technology for stripping ammonia from landfill leachate under tropical conditions.


Subject(s)
Ammonia/isolation & purification , Waste Management/methods , Ammonia/analysis , Oxygen/chemistry , Tropical Climate
6.
Poult Sci ; 89(8): 1622-8, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20634516

ABSTRACT

Aflatoxins (AF) have a high impact in both human and animal health, causing significant economic losses in the poultry industry, especially by diminution of avian growth, feed efficiency, and product quality. Aflatoxins affect the whole organism, particularly liver and kidney. The objective of this study was to evaluate renal function alterations in laying hens during chronic AF ingestion. Randomly, 84 Leghorn Hy-Line laying hens (13 wk old) were assigned into 4 experimental groups (n = 21): 0.0, 0.5, 1.0, and 1.5 mg of AF/kg of feed. The AF (B(1), B(2), G(1), and G(2)) was obtained from 2 toxicogenic local strains of Aspergillus flavus grown in corn grains; the grain was sterilized, ground, and added to basal diets to achieve the selected AF concentrations. Hens ingested, during 17 and 42 wk, feed contaminated with AF. Data were analyzed in a 4 x 2 factorial arrangement. Hens were anesthetized, ureteral urine samples were collected, and arterial blood samples were taken. The renal functional tests were evaluated by spectrophotometric and flame photometric methods, including a) Na, K, Ca, and phosphate fractional excretions; b) renal hemodynamic studies, glomerular filtration rate and renal plasma flow by inulin and p-aminohippurate clearances, respectively; and c) identification of macroscopic and histopathologic lesions. The hens intoxicated at all levels of AF showed significant (P < 0.05) increases in Ca, Na, and phosphate fraction excretions. Sodium and phosphates were excreted in a pattern of response time-dose. However, glomerular filtration rate exhibited a significant reduction (P < 0.05). The K fractional excretion and renal plasma flow remained unchanged. These results suggest that AF chronic ingestion affects renal functions of laying hens and induces Ca(++), (-3)PO(4), and Na(+) losses, which are of great concern to the poultry industry.


Subject(s)
Aflatoxins/toxicity , Kidney/drug effects , Oviposition/drug effects , Renal Circulation/drug effects , Administration, Oral , Aflatoxins/administration & dosage , Animal Feed , Animals , Body Weight , Calcium/urine , Chickens , Dose-Response Relationship, Drug , Female , Food Contamination , Glomerular Filtration Rate/drug effects , Humans , Kidney/physiopathology , Kidney Function Tests , Phosphates/urine , Potassium/urine , Sodium/urine
7.
J Invest Dermatol ; 117(2): 179-87, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11511292

ABSTRACT

The Comèl-Netherton syndrome is an autosomal recessive multisystemic disorder characterized by localized or generalized congenital ichthyosis, hair shaft abnormalities, immune deficiency, and markedly elevated IgE levels. Life-threatening complications during infancy include temperature and electrolyte imbalance, recurrent infections, and failure to thrive. To study the clinical presentations of the Comèl-Netherton syndrome and its molecular cause, we ascertained 19 unrelated families of various ethnic backgrounds. Results of initial linkage studies mapped the Comèl-Netherton syndrome in 12 multiplex families to a 12 cM interval on 5q32, thus confirming genetic homogeneity of Comèl-Netherton syndrome across families of different origins. The Comèl-Netherton syndrome region harbors the SPINK5 gene, which encodes a multidomain serine protease inhibitor (LEKTI) predominantly expressed in epithelial and lymphoid tissues. Recently, recessive mutations in SPINK5 were identified in several Comèl-Netherton syndrome patients from consanguineous families. We used heteroduplex analysis followed by direct DNA sequencing to screen all 33 exons and flanking intronic sequences of SPINK5 in the affected individuals of our cohort. Mutation analysis revealed 17 distinct mutations, 15 of which were novel, segregating in 14 Comèl-Netherton syndrome families. The nucleotide changes included four non-sense mutations, eight small deletions or insertions leading to frameshift, and five splice site defects, all of which are expected to result in premature terminated or altered translation of SPINK5. Almost half of the mutations clustered between exons 2 and 8, including two recurrent mutations. Genotype-phenotype correlations suggested that homozygous nucleotide changes resulting in early truncation of LEKT1 are associated with a severe phenotype. For the first time, we used molecular data to perform prenatal testing, thus demonstrating the feasibility of molecular diagnosis in the Comèl-Netherton syndrome.


Subject(s)
Carrier Proteins , Gene Deletion , Hair/abnormalities , Ichthyosiform Erythroderma, Congenital/genetics , Prenatal Diagnosis , Serine Proteinase Inhibitors/genetics , Adolescent , Adult , Child , Child, Preschool , Codon, Nonsense , DNA Mutational Analysis , DNA Primers , Dermatitis, Atopic/genetics , Family Health , Female , Genetic Linkage , Heteroduplex Analysis , Humans , Infant , Male , Middle Aged , Molecular Sequence Data , Phenotype , Pregnancy , Proteinase Inhibitory Proteins, Secretory , Serine Peptidase Inhibitor Kazal-Type 5
8.
Eur J Dermatol ; 10(3): 190-4, 2000.
Article in English | MEDLINE | ID: mdl-10725816

ABSTRACT

The name epidermal nevus syndrome could be applied to a group of clinically and histopathologically different entities as has been pointed out by Happle. Phacomatosis pigmentokeratotica is a further type of epidermal nevus syndrome distinguished by the presence of a sebaceous nevus and a contralateral speckled lentiginous nevus of the papular type, associated with skeletal or neurological abnormalities. Three new cases of this recently delineated syndrome are presented. A common origin may account for the temporal and spatial relationship between the epidermal and the speckled lentiginous nevus. The concept of melanocytic-epidermal twin spotting similar to the interpretation of vascular twin spotting could explain the pathogenesis of this entity.


Subject(s)
Neurocutaneous Syndromes/pathology , Nevus/pathology , Child , Child, Preschool , Diagnosis, Differential , Humans , Male , Syndrome
9.
Microbiol Immunol ; 42(5): 341-6, 1998.
Article in English | MEDLINE | ID: mdl-9654365

ABSTRACT

A monoclonal antibody (MAb 84) raised against the dissociated CFA/I fimbriae of enterotoxigenic Escherichia coli was characterized with regard to antigen binding and epitope specificity. Enzyme-linked immunosorbent assay (ELISA) showed that MAb 84 had higher affinity to CFA/I subunits than to intact CFA/I fimbriae and recognized a Salmonella flagellin carrying an insert corresponding to amino acids 32 to 45 of the CFA/I subunit. Fine epitope mapping based on the Pepscan technique showed that the peptide 39TFESY43, derived from the sequence of the mature CFA/I subunit, was specifically recognized by MAb 84. The 39TFESY43 sequence is probably not accessible on the surface of the native CFA/I fimbriae since MAb 84 did not bind to intact fimbriae as evaluated in inhibition ELISA tests. Moreover, MAb 84 did not agglutinate fimbriated ETEC cells nor inhibit CFA/I-mediated hemagglutination or the adhesion to Caco-2 cells.


Subject(s)
Antibodies, Monoclonal/immunology , Bacterial Proteins/immunology , Epitopes/immunology , Escherichia coli/immunology , Fimbriae Proteins , Fimbriae, Bacterial/immunology , Animals , Antibodies, Monoclonal/biosynthesis , Bacterial Adhesion/immunology , Bacterial Outer Membrane Proteins/immunology , Caco-2 Cells/immunology , Cloning, Molecular , Epitope Mapping , Hemagglutination Inhibition Tests , Humans , Mice , Mice, Inbred BALB C
10.
Dermatol. argent ; 4(1): 41-3, ene.-mar.1998. ilus
Article in Spanish | BINACIS | ID: bin-18501

ABSTRACT

Se comunican 2 pacientes gemelas, de ocho meses de vida, que presentan lesiones maculares eritematovioláceas localizadas en el dorso y regiones laterales de los pies, con edema de los dedos. Se realizan los estudios histopatológicos que son compatibles con eritema pernio, entidad que se diagnostica con poca frecuencia en lactantes (AU)


Subject(s)
Humans , Female , Infant , Chilblains/diagnosis , Diseases in Twins/diagnosis , Chilblains/etiology , Chilblains/drug therapy , Diagnosis, Differential
11.
Dermatol. argent ; 4(1): 41-3, ene.-mar.1998. ilus
Article in Spanish | LILACS | ID: lil-215586

ABSTRACT

Se comunican 2 pacientes gemelas, de ocho meses de vida, que presentan lesiones maculares eritematovioláceas localizadas en el dorso y regiones laterales de los pies, con edema de los dedos. Se realizan los estudios histopatológicos que son compatibles con eritema pernio, entidad que se diagnostica con poca frecuencia en lactantes


Subject(s)
Humans , Female , Infant , Chilblains/diagnosis , Diseases in Twins/diagnosis , Chilblains/drug therapy , Chilblains/etiology , Diagnosis, Differential
14.
Pediatr Dermatol ; 12(2): 159-63, 1995 Jun.
Article in English | MEDLINE | ID: mdl-7659644

ABSTRACT

We report a 1-year-old boy with an extensive cutaneous vascular malformation, oculocutaneous pigmentation, and severe neurologic abnormalities from birth, as well as a selective IgA deficiency. Ultrastructural study demonstrated prominent endothelial cells in the luminal of the blood vessels. The diagnosis of phacomatosis pigmentovascularis type IIb seemed appropriate for this patient.


Subject(s)
Blood Vessels/abnormalities , IgA Deficiency/pathology , Pigmentation Disorders/pathology , Skin/blood supply , Angiomatosis/pathology , Brain Diseases/pathology , Endothelium, Vascular/pathology , Eye Diseases/pathology , Humans , Infant , Intellectual Disability/pathology , Male , Nevus, Pigmented/pathology , Skin Neoplasms/pathology
15.
Pediatr Dermatol ; 9(1): 52-6, 1992 Mar.
Article in English | MEDLINE | ID: mdl-1574477

ABSTRACT

A female infant was classified as having oral-facial-digital syndrome (OFDS) type 1, with oral (cleft palate, bifid uvula, lingual cleft, numerous hypertrophic frenula), facial (numerous milia on face, scalp, and ears; frontal bossing; hypertelorism; hypoplasia of nasal alar cartilage; micrognathia), and digital (bilateral brachydactyly of hands) symptoms. She also had diffuse, nonscarring alopecia with wiry, dry hair. Results of roentgenographic and ultrasound studies were normal. At her present age of 11 months, her psychomotor development is appropriate for her age.


Subject(s)
Orofaciodigital Syndromes/diagnosis , Skin Diseases/pathology , Female , Humans , Infant, Newborn , Orofaciodigital Syndromes/complications , Skin Diseases/etiology
16.
Rev. argent. dermatol ; 71(3): 146-54, jul.-set. 1990. tab, ilus
Article in Spanish | BINACIS | ID: bin-27299

ABSTRACT

Se presentan 9 pacientes con lesiones cutáneas de esclerosis tuberosa, cuya edad máxima fue de 11 años, estudiados por métodos no cruentos para determinar su compromiso interno. Hemos encontrado que éste fue frecuente y con predominio del S.N.C. y corazón (AU)


Subject(s)
Infant , Child, Preschool , Child , Humans , Male , Female , Tuberous Sclerosis/diagnosis , Skin Manifestations/complications , Tuberous Sclerosis/complications , Ultrasonography
17.
Rev. argent. dermatol ; 71(3): 146-54, jul.-set. 1990. tab, ilus
Article in Spanish | LILACS | ID: lil-96300

ABSTRACT

Se presentan 9 pacientes con lesiones cutáneas de esclerosis tuberosa, cuya edad máxima fue de 11 años, estudiados por métodos no cruentos para determinar su compromiso interno. Hemos encontrado que éste fue frecuente y con predominio del S.N.C. y corazón


Subject(s)
Infant , Child, Preschool , Child , Humans , Male , Female , Tuberous Sclerosis/diagnosis , Skin Manifestations/complications , Tuberous Sclerosis/complications , Ultrasonography
18.
Rev. argent. dermatol ; 71(1): 14-7, ene.-mar. 1990. ilus, tab
Article in Spanish | BINACIS | ID: bin-26860

ABSTRACT

Se comunica un caso de granuloma anular subcutáneo en un niño de 10 años de edad. El cuadro clínico se manifiesta por múltiples nódulos subcutáneos en áreas acrales. Se menciona el antecedente de una B talasemia menor familiar, hecho no referido en la bibliografía. La ausencia de manifestaciones reumáticas, asociada a su cuadro histológico avalan el diagnóstico de G.A.S. Las lesiones persistieron durante años a pesar del tratamiento con corticoides (AU)


Subject(s)
Child , Humans , Male , Skin Diseases/diagnosis , Granuloma/diagnosis , Rheumatoid Nodule/diagnosis , Diagnosis, Differential
19.
Rev. argent. dermatol ; 71(1): 14-7, ene.-mar. 1990. ilus, tab
Article in Spanish | LILACS | ID: lil-102131

ABSTRACT

Se comunica un caso de granuloma anular subcutáneo en un niño de 10 años de edad. El cuadro clínico se manifiesta por múltiples nódulos subcutáneos en áreas acrales. Se menciona el antecedente de una B talasemia menor familiar, hecho no referido en la bibliografía. La ausencia de manifestaciones reumáticas, asociada a su cuadro histológico avalan el diagnóstico de G.A.S. Las lesiones persistieron durante años a pesar del tratamiento con corticoides


Subject(s)
Child , Humans , Male , Granuloma/diagnosis , Skin Diseases/diagnosis , Diagnosis, Differential , Rheumatoid Nodule/diagnosis
20.
Med Cutan Ibero Lat Am ; 18(1): 9-12, 1990.
Article in Spanish | MEDLINE | ID: mdl-2214934

ABSTRACT

Four cases of newborn children who presented pedal papules since birth, are reported. They showed the following features, different from the ones seen in adults: a solitary lesion, bigger size, localization on medial plantar region aspect of the heel, presence at birth, absence of an obvious piezogenic factor, physiopathogenic model that explains the development of lesions in adults, which are compared to those appearing in the newborn, are proposed.


Subject(s)
Foot Dermatoses/pathology , Skin Diseases, Vesiculobullous/pathology , Female , Heel , Humans , Infant, Newborn , Male
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