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1.
Br J Dermatol ; 182(1): 147-155, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31049933

RESUMO

BACKGROUND: The malignant mechanisms that control the development of cutaneous T-cell lymphoma (CTCL) are beginning to be identified. Recent evidence suggests that disturbances in specific intracellular signalling pathways, such as RAS-mitogen-activated protein kinase, T-cell receptor (TCR)-phospholipase C gamma 1 (PLCG1)-nuclear factor of activated T cells (NFAT) and Janus kinase (JAK)-signal transducer and activator of transcription (STAT), may play an essential role in the pathogenesis of CTCL. OBJECTIVES: To investigate the mechanisms controlling disease development and progression in mycosis fungoides (MF), the most common form of CTCL. METHODS: We collected 100 samples that were submitted for diagnosis of, or a second opinion regarding, MF between 2001 and 2018, 80% of which were in the early clinical stages of the disease. Formalin-fixed paraffin-embedded tissues were used for histological review and to measure the expression by immunohistochemistry of surrogate markers of activation of the TCR-PLCG1-NFAT, JAK-STAT and NF-κB pathways. Folliculotropism and large-cell transformation were also examined. RESULTS: NFAT and nuclear factor kappa B (NF-κB) markers showed a comparable activation status in early and advanced stages, while STAT3 activation was more frequent in advanced stages and was associated with large-cell transformation. Consistently with this observation, STAT3 activation occurred in parallel with MF progression in two initially MF-negative cases. A significant association of NFAT with NF-κB markers was also found, reflecting a common mechanism of activation in the two pathways. Genomic studies identified nine mutations in seven genes known to play a potential role in tumorigenesis in T-cell leukaemia/lymphoma, including PLCG1, JAK3 and STAT3, which underlies the activation of these key cell-survival pathways. A higher mutational allele frequency was detected in advanced stages. CONCLUSIONS: Our results show that STAT3 is activated in advanced cases and is associated with large-cell transformation, while the activation of NFAT and NF-κB is maintained throughout the disease. These findings could have important diagnostic and therapeutic implications. What's already known about this topic? Mycosis fungoides is characterized by a clonal expansion of T cells in the skin. The mechanisms controlling disease development and progression are not fully understood. What does this study add? An association of the nuclear factor of activated T cells and nuclear factor kappa B pathways was found, which could reflect a common mechanism of activation. These pathways were activated in early and advanced stages at the same level. Signal transducer and activator of transcription 3 activation was associated with large-cell transformation and was more frequent in advanced stages. A genomic analysis of cutaneous T-cell lymphoma-associated genes was performed. Nine mutations were detected. What is the translational message? These results could have important implications for the treatment of MF in the near future.


Assuntos
Linfoma Cutâneo de Células T , Micose Fungoide , NF-kappa B , Fatores de Transcrição NFATC , Fator de Transcrição STAT3 , Neoplasias Cutâneas , Humanos , Micose Fungoide/genética , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Neoplasias Cutâneas/genética , Linfócitos T/metabolismo
2.
J Environ Manage ; 259: 110044, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31929029

RESUMO

Graphene oxide (GO) is a single-atom-thick sheet of carbon with oxygen-containing functional groups decorating its basal plane and edge sites. Most of its high surface area can be lost due to restacking of individual layers during the synthesis and drying of GO-based bulk sorbents. There is great interest to increase the specific surface area of graphene-based sorbents by introducing organic molecules as "pillaring agents" between GO sheets to hinder the stacking process and create sorbents with elevated surface area. This work synthesizes pillared GO by introducing chitosan (CS), a linear polysaccharide with various molecular weights. A composite of low molecular weight CS at a CS/GO ratio of 0.1 is shown to have the highest specific surface area (up to 70.5 m2/g) in comparison to the medium and high CS molecular weight, pristine GO, and the CS/GO composite materials. The affinity of the optimized GO/CS composites towards benzene, toluene, and naphthalene was evaluated at 19.3 mg/L of organic matter content while altering pH. Sips and Langmuir adsorption isotherm models well described the adsorption behavior, and benzene adsorption performance was reduced at low pH. Related to the presence of dissolved organic matter (DOM) in solution, lower diffusivity constants (k1) in hydrocarbon systems were recorded. Our results demonstrate the feasibility of CS as a potential pillaring agent in CS/GO composites to increase specific surface area and enhance the capture of soluble hydrocarbons from aqueous solutions.


Assuntos
Grafite , Adsorção , Concentração de Íons de Hidrogênio , Óxidos , Água
3.
Biodegradation ; 30(5-6): 401-413, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31187383

RESUMO

Activated carbon cloths (ACCs) were used as biofilms supports in the anaerobic biotransformation of 4-nitrophenol (4NP). As received ACC material (AW) was oxidized with HNO3 (OX) and then functionalized with anthraquinone-2,6-disulfonate (AQ). The three ACCs were packed in hybrid UASB reactors and seeded with anaerobic granular sludge for biotransformation experiments. The results indicated that ACC-packed bioreactors improved the biotransformation of 4NP by twofold as compared to the control reactor without support materials. However, the biotransformation effciency of AW, OX and AQ was very similar (59%), indicating the role of ACC as biofilm support and not as redox mediator. After 4NP biotransformation several physicochemical and biological changes were observed like (1) the point of zero charge (pHPZC) shift from acidic values (AW = 5.0, OX = 3.4, AQ = 3.1) to neutral values (pHPZC = 7.6 on average), (2) increase in the concentration of acidic and basic surface functional groups over ACC materials and the amount of supported biomass on ACCs due to biofilm formation, and (3) enrichment of exoelectrogenic microorganisms belonging to the genera Geobacter over carbonyl-rich ACC surface as revealed by 16S rRNA amplicon sequencing. Overall, the results suggest that chemical modifications of ACCs changed the microbial composition of the biofilm, but the higher concentration of carbonyl groups on ACC did not affect the biotransformation of 4NP.


Assuntos
Reatores Biológicos , Carvão Vegetal , Biodegradação Ambiental , Biofilmes , Biotransformação , Nitrofenóis , RNA Ribossômico 16S , Esgotos , Eliminação de Resíduos Líquidos
4.
Colloids Surf A Physicochem Eng Asp ; 566: 188-195, 2019 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-31662597

RESUMO

The novel application of magnetite containing reduced graphene oxide nanosacks (MrGO-N) as electron shuttles to improve the reductive degradation of pharmaceutical pollutant, iopromide (IOP), was evaluated. The MrGO-N were synthesized by ultrasonicated nebulization process, and their physicochemical characterization was performed by potentiometric titrations, zeta potential, high resolution transmission electron microscopy (HR-TEM), X-ray diffraction, as well as by Raman and Fourier transform infrared spectroscopies. Results demonstrated the thermal reduction of precursor graphene oxide sheets, the removal of different oxygenated groups, and the successful assembly of magnetite nanoparticles (MNP) in the graphene sacks. Also, reduction experiments revealed 72 % of IOP removal efficiency and up to 2.5-fold faster degradation of this pollutant performed with MrGO-N as redox catalysts in batch assays and with sulfide as electron donor. Chemical transformation pathway of IOP provides evidence of complete dehalogenation and further transformation of aromatic ring substituents. Greater redox-mediating ability of MrGO-N was observed, which was reflected in the catalytic activity of these nanomaterials during the reductive degradation of IOP. Transformation byproducts with simpler chemical structure were identified, which could lead to complete degradation by conventional methodologies in a complementary treatment process. Redox-mediating activity of MrGO-N could potentially be applied in wastewater treatment systems in order to facilitate the biodegradation of priority contaminants.

5.
Appl Microbiol Biotechnol ; 102(20): 8951-8961, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30058007

RESUMO

The redox-mediating capacity of magnetic reduced graphene oxide nanosacks (MNS) to promote the reductive biodegradation of the halogenated pollutant, iopromide (IOP), was tested. Experiments were performed using glucose as electron donor in an upflow anaerobic sludge blanket (UASB) reactor under methanogenic conditions. Higher removal efficiency of IOP in the UASB reactor supplied with MNS as redox mediator was observed as compared with the control reactor lacking MNS. Results showed 82% of IOP removal efficiency under steady state conditions in the UASB reactor enriched with MNS, while the reactor control showed IOP removal efficiency of 51%. The precise microbial transformation pathway of IOP was elucidated by high-performance liquid chromatography coupled to mass spectroscopy (HPLC-MS) analysis. Biotransformation by-products with lower molecular weight than IOP molecule were identified in the reactor supplied with MNS, which were not detected in the reactor control, indicating the contribution of these magnetic nano-carbon composites in the redox conversion of this halogenated pollutant. Reductive reactions of IOP favored by MNS led to complete dehalogenation of the benzene ring and partial rupture of side chains of this pollutant, which is the first step towards its complete biodegradation. Possible reductive mechanisms that took place in the biodegradation of IOP were stated. Finally, the novel and successful application of magnetic graphene composites in a continuous bioreactor to enhance the microbial transformation of IOP was demonstrated.


Assuntos
Bactérias/metabolismo , Meios de Contraste/metabolismo , Iohexol/análogos & derivados , Magnetismo/métodos , Nanocompostos/química , Anaerobiose , Biodegradação Ambiental , Reatores Biológicos/microbiologia , Biotransformação , Meios de Contraste/química , Iohexol/química , Iohexol/metabolismo , Magnetismo/instrumentação , Oxirredução , Esgotos/química , Esgotos/microbiologia
6.
J Hazard Mater ; 162(1): 503-11, 2009 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-18585858

RESUMO

The aim of this study was to investigate the selectivity of chitosan for cadmium, copper and lead in the presence and absence of natural organic matter (NOM) in different pH solutions. Adsorption isotherms of one and three adsorbates at initial concentration of 5-100mg/L were carried out in batch reactors at pH 4, 5, or 7 and 25 degrees C in reactive and clarified water. The chitosan employed had a MW of 107.8 x 10(3)g/mol and degree of acetylation (DA) of 33.7%. The chitosan adsorption capacity at pH 4 in reactive water was 0.036, 0.016, 0.010mmol/g for Pb(2+), Cd(2+), and Cu(2+), respectively, and it decreased for Pb(2+) and Cd(2+) in clarified water. Conversely, experiments carried out in clarified water showed that the cadmium adsorption capacity of chitosan was enhanced about three times by the presence of NOM at pH 7: an adsorption mechanism was proposed. Furthermore, it was found that the biosorbent selectivity, in both reactive and clarified water at pH 4, was as follows Cu(2+)>Cd(2+)>Pb(2+). Finally, the preliminary desorption experiments of Cd(2+) conducted at pH 2 and 3 reported 68 and 44.8% of metal desorbed, which indicated that the adsorption mechanism occurred by electrostatic interactions and covalent bonds.


Assuntos
Cádmio/isolamento & purificação , Quitosana/análise , Cobre/isolamento & purificação , Chumbo/isolamento & purificação , Acetilação , Adsorção , Cádmio/análise , Quitosana/química , Cobre/análise , Concentração de Íons de Hidrogênio , Íons , Chumbo/análise , Espectroscopia de Ressonância Magnética , Peso Molecular , Solubilidade , Soluções , Espectrofotometria Infravermelho , Temperatura , Termodinâmica , Água
7.
RSC Adv ; 10(1): 179-186, 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-35492537

RESUMO

New alternatives for the removal of transition metal ions that present an environmental risk are required. The chemical adsorption of these ions on surfaces with chemisorbent properties represents a promising area of research. In this work, manganite (γ-MnOOH) nanorods were synthesized, with a surface area of 20.22 m2 g-1, pore size of 32.18 nm and pore volume of 0.1627 cm3 g-1. After chemical and structural characterization of the manganite sample, it was evaluated as an adsorbent of Cu(ii) from aqueous solution. The equilibrium adsorption data were well fitted by the Langmuir isotherm, and the results indicated that the maximum adsorption capacity of Cu(ii) was 11.926 mg g-1. Cu(ii) ion adsorption on the manganite surface is a spontaneous and exothermic process (ΔG°< 0 and ΔH°< 0). The negative value of ΔS° suggests the stability of the adsorption process without structural change at the manganite-aqueous solution interface. A scheme for chemisorption of Cu(ii) ions on the hydroxylated surface of manganite is proposed.

8.
Water Res ; 36(5): 1244-52, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11902779

RESUMO

The surface of activated carbon cloth (ACC), based on polyacrylonitrile fibre as a precursor, was oxidised using nitric acid, ozone and electrochemical oxidation to enhance cadmium ion exchange capacity. Modified adsorbents were physically and chemically characterised by pH titration, direct titration, X-ray photoelectron spectroscopy, elemental analysis, surface area and porosimetry, and scanning electron microscopy. BET surface area decreased after oxidation, however, the total ion exchange capacity increased by a factor of approximately 3.5 compared to the commercial as-received ACC. A very significant increase in cadmium uptake, by a factor of 13, was observed for the electrochemically oxidised ACC. Equilibrium sorption isotherms were determined at pH 4, 5 and 6 and these showed that cadmium uptake increased with increasing pH. There was clear evidence of physical damage to ozone-oxidised fibre, however, acid and electrochemically oxidised samples were completely stable.


Assuntos
Cádmio/química , Carbono/química , Purificação da Água/métodos , Adsorção , Concentração de Íons de Hidrogênio , Oxirredução , Poluentes da Água
9.
Invest Clin ; 38(4): 203-17, 1997 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-9527388

RESUMO

Microtia is a congenital malformation characterized by total or partial absence of the whole auricle or any of its components, varying from a small auricle to the total absence (anotia). There may be associated atresia of the external auditory meatus. The frequency varies in different parts of the world between 0.4 and 5.5/10,000 newborns. In this paper we report the clinical and epidemiological characterization of this congenital malformation in a sample of 97.759 neonates born at the Ruíz y Páez Hospital in Ciudad Bolivar, Venezuela, between April 1978 and December 1994. A total of 38 patients with microtia were identified. The global frequency was 3.8 per 10,000/newborns. In 47.4% of the patients microtia was an isolated malformation and in 52.6% was associated to other malformations. Sixty three percent of the affected were males. The unilateral form was present in 81.5% of the cases, more frequently on the right side. The annual frequency of the defect was stable over the studied years. The clinical classification of the cases with associated malformations allowed us to establish that 18.4% of the cases correspond to developmental fields defects, associated to preauricular dimples and/or tags, 7.8% were cases of the facio-auriculo-vertebral spectrum and in 15.7% the microtia was part of a monogenic or chromosomal syndrome. In 10.5% it was not possible to define any etiological or pathogenic mechanism. The frequency obtained in this study for microtia shows intermediate values when compared with others reports from Latin America.


Assuntos
Orelha Externa/anormalidades , Anormalidades Múltiplas/epidemiologia , Anormalidades Múltiplas/genética , Aberrações Cromossômicas/epidemiologia , Aberrações Cromossômicas/genética , Transtornos Cromossômicos , Anormalidades Congênitas/epidemiologia , Anormalidades Congênitas/genética , Feminino , Humanos , Incidência , Recém-Nascido , América Latina/epidemiologia , Masculino , Exposição Materna , Fatores de Risco , Síndrome , Venezuela/epidemiologia
10.
Gac Med Mex ; 136(3): 221-47, 2000.
Artigo em Espanhol | MEDLINE | ID: mdl-10893851

RESUMO

The use of single-cell polymerize chain reaction analysis has allowed for a better understanding of the origin of Hodgkin's disease, Burkitt. The study of the mechanisms regulating apoptosis and the survival of neoplastic clones have opened a whole area of research. The Revised European-American List of lymphoid neoplasms must be presented in a form that facilitates the understanding, learning, and teaching of these disorders. There is a great need for a better definition of the new category of lymphoplasmacytic lymphoma, the variants of mantle cell lymphoma and marginal zone B-cell lymphomas, and the coming of age of the NK-cell lymphomas. Based on current data, it is difficult to determine the site of transplantation in the management of follicular, low-grade non-Hodgkin's lymphoma. These patients remain at risk of relapse after transplantation, mirroring results with conventional therapy. The treatment of aggressive lymphomas remains an area of significant controversy. The Intergroup Study concluded that none of the more recent regimens was superior to CHOP. Recent data suggest that high-dose therapy with consolidative autologous or allogenic transplant may benefit patients with aggressive histology lymphoma who have poor prognostic features.


Assuntos
Linfoma/terapia , Humanos
11.
J Hazard Mater ; 184(1-3): 268-272, 2010 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-20813453

RESUMO

Different metal-oxides nanoparticles (MONP) including α-Al(2)O(3), ZnO and Al(OH)(3), were utilized as adsorbents to immobilize anthraquinone-2,6-disulfonate (AQDS). Immobilized AQDS was subsequently tested as a solid-phase redox mediator (RMs) for the reductive decolorization of the azo dye, reactive red 2 (RR2), by anaerobic sludge. The highest adsorption capacity of AQDS was achieved on Al(OH)(3) nanoparticles, which was ∼0.16 mmol g(-1) at pH 4. Immobilized AQDS increased up to 7.5-fold the rate of decolorization of RR2 by anaerobic sludge as compared with sludge incubations lacking AQDS. Sterile controls including immobilized AQDS did not show significant (<3.5%) RR2 decolorization, suggesting that physical-chemical processes (e.g. adsorption or chemical reduction) were not responsible for the enhanced decolorization achieved. Immobilization of AQDS on MONP was very stable under the applied experimental conditions and spectrophotometric screening did not detect any detachment of AQDS during the reductive decolorization of RR2, confirming that immobilized AQDS served as an effective RMs. The present study constitutes the first demonstration that immobilized quinones on MONP can serve as effective RMs in the reductive decolorization of an azo dye. The immobilizing technique developed could be applied in anaerobic wastewater treatment systems to accelerate the redox biotransformation of recalcitrant pollutants.


Assuntos
Cor , Nanopartículas Metálicas , Adsorção , Catálise , Oxirredução , Óxidos/química , Espectroscopia de Infravermelho com Transformada de Fourier
18.
Cir. plást. ibero-latinoam ; 37(1): 91-96, ene.-mar. 2011. ilus
Artigo em Espanhol | IBECS (Espanha) | ID: ibc-96886

RESUMO

A la hora de valorar las múltiples técnicas empleadas en el rejuvenecimiento facial y centrándonos de manera particular en aquellos procedimientos mínimamente invasivos complementarios a las intervenciones habituales en Cirugía Plástica-Estética, cobra especial relevancia el conocimiento exhaustivo de las estructuras musculares implicadas en la mímica facial. A tal efecto, se ha realizado un estudio anatómico en cadáveres frescos, en los que se han disecado las principales estructuras referidas. Se presenta un resumen iconográfico de los músculos faciales implicados, haciendo hincapié en su anatomía descriptiva y funcional, así como un recuerdo de las principales áreas problemáticas por alguna circunstancia especial (presencia de un nervio sensitivo o motor) (AU)


To value the multiple technologies involved in facial rejuvenation and focusing in those minimally invasive complementary procedures to the usual Plastic and Aesthetic Surgeries, it´s very important the exhaustive knowledge of the muscular structures involved in the facial movements. To such an effect, an anatomical study has been realized in fresh corpses, dissecting the principal above-mentioned structures. We present an iconographic summary of the facial implied muscles, emphasizing in his descriptive and functional anatomy, as well as a recollection of the principal problematic areas for some special circumstance (presence of a sensory or motornerve) (AU)


Assuntos
Humanos , Dissecação/métodos , Músculos Faciais/anatomia & histologia , Face/anatomia & histologia , Rejuvenescimento , Técnicas Cosméticas , Cadáver
19.
Cir. plást. ibero-latinoam ; 36(4): 321-326, dic. 2010. tab
Artigo em Espanhol | IBECS (Espanha) | ID: ibc-96765

RESUMO

El método de elección para la cobertura de algunos defectos cutáneos es el autoinjerto de piel parcial; sin embargo, sufre retracciones que pueden adquirir gran relevancia sobre áreas especiales. Diferentes autores han intentado evitar estos déficits funcionales mediante la interposición de matrices de regeneración dérmica monocapa e injerto en un solo tiempo quirúrgico. Diseñamos un estudio para comparar la tasa de integración de los injertos sobre una matriz monocapa con y sin la aplicación de terapia de vacío tipo VAC® sobre ellos. Se aleatorizaron 20 pacientes con defectos cutáneos sobre áreas especiales en 2 grupos. Recogimos los datos epidemiológicos y la etiología del defecto (quemadura aguda, secuelas de quemadura o defectos secundarios a extracción de colgajo fasciocutáneo). En 10 casos (Grupo I) se aplicó matriz dérmica monocapa Matriderm ® más un injerto cutáneo de piel parcial, realizando un cambio de vendaje a los 7 días y luego cada 3-4 días hasta su estabilización. En otros 10 pacientes (Grupo II), tras realizar el mismo protocolo quirúrgico se aplicó VAC ® durante una semana y se cambió hasta la estabilización del injerto. La evaluación del prendimiento del injerto y su estabilidad la realizó un observador ciego. Se recogieron todas las complicaciones surgidas en el postoperatorio hasta 3 meses después de la estabilidad del injerto. Comprobamos la homogeneidad de ambos grupos para las variables epidemiológicas de los pacientes, así como para la etiología de los defectos. (..) (AU)


Split thickness autografts are the gold standard for wound coverage. However, scars and retractions are frequent after skin grafts, and would be severe over special regions. Different authors avoid these complications using a dermal substitute interposed between the wound and the skin graft in the first surgical time. A prospective study was designed to evaluate the split thickness skin graft uptake time over a monolayer matrix, with and without a vacuum assisted therapy device (VAC®). Twenty patients with a full thickness wound over a special region were randomized between 2 groups. Epidemiological data and wound ethology(acute burn, burn sequelae or donor site after a fasciocutaneous flap raised)were collected. Matriderm ® (mono layer dermal substitute) and a split thickness skin graft was applied over 10 cases (Group I). The dressing was changed after 7 days, and every 3-4 days until the skin graft was uptake and stable. Another 10 cases were treated with the same surgical strategy (Group II). After surgery, a vacuum assisted therapy device(VAC®) was applied until the graft was uptake. The skin graft evaluation was done by a blind observer. All complications were reported until 3months after the skin graft was stable. The homogeneity between groups was assessed. Averaged uptake time was 17, 6 ± 8 days, and the total complication rate was 20%. Statistically differences were not found between the 2 groups for the complication rate. The uptake time was 21,4 ± 9 days in the Group I and 13,9 ± 4 days in the Group II. These differences was statically significative. As a conclusion, the use of monolayer dermal substitutes is safe, with skin graft uptake rate of 85%. Time for skin graft uptake over a monolayer dermal matrix is shorter using a VAC ® device over the skin graft, with similar complication rate (AU)


Assuntos
Humanos , Dispositivos para Expansão de Tecidos , Pele Artificial , Anormalidades da Pele/cirurgia , Queimaduras/cirurgia , Transplante de Pele , Transplante Autólogo , Complicações Pós-Operatórias/epidemiologia
20.
Rev Med Panama ; 16(2): 130-7, 1991 May.
Artigo em Espanhol | MEDLINE | ID: mdl-1924902

RESUMO

Two unusual cases of acute cholangitis are presented. One patient had a 3 cm. common duct stone successfully fragmented with an endoscopic mechanical lithotriptor. The other patient had a hemigastrectomy with a Billroth II anastomosis. A combined percutaneous--endoscopic approach was required to perform the sphincterotomy and remove the duct stones. The different treatment alternatives and the literature are discussed.


Assuntos
Colangite/terapia , Drenagem/métodos , Endoscopia do Sistema Digestório , Litotripsia , Doença Aguda , Idoso , Terapia Combinada , Humanos , Masculino , Panamá
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