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1.
J Hazard Mater ; 416: 126199, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492963

RESUMO

This study reports the photocatalytic degradation of diclofenac by hybrid materials prepared by combination of graphitic carbon nitride (g-C3N4) and titanium-metal organic framework (NH2-MIL-125), in different mass proportions (MOF:C3N4 of 25:75, 50:50 and 75:25). The hybrid materials were fully characterized, and their properties compared to those of the individual components, whose presence was confirmed by XRD. The porous structure was the result of the highly microporous character of the MOF and the non-porous one of g-C3N4. The band gap values were very close to that of MOF component. Photoluminescence measurements suggested an increase on the recombination rate associated to the presence of g-C3N4. Photodegradation tests of diclofenac (10 mg·L-1) were performed under UV LED irradiation at 384 nm. The hybrid materials showed higher photocatalytic activity than the individual components, suggesting the occurrence of some synergistic effect. The photocatalyst with a MOF:g-C3N4 ratio of 50:50 yielded the highest conversion rate, allowing complete disappearance of diclofenac in 2 h. Experiments with scavengers showed that superoxide radicals and holes played a major role in the photocatalytic process photodegradation, being that of hydroxyl radicals less significant. From the identification of by-products species, a degradation pathway was proposed for the degradation of diclofenac under the experimental operating conditions.


Assuntos
Diclofenaco , Água , Catálise , Fotólise
2.
Int J Cosmet Sci ; 41(6): 585-593, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31509264

RESUMO

OBJECTIVE: The organic ultraviolet UVB filter 2-ethylhexyl 4-methoxycinnamate (EHMC) was encapsulated in microparticles (MPs) of sodium alginate and co-loaded with vitamin E (Vit.E) by an extrusion process using an aerodynamically assisted jetting (AAJ) methodology. The aim was to assess the effect of encapsulation concerning UVB filter release from the MPs and its photochemical stability. METHODS: The EHMC photostability was analysed by exposing the samples (both MPs in aqueous dispersion and incorporated in a cream preparation) during 1 h to simulated solar light. For the MPs (empty-MP, EHMC-MP and EHMC + Vit.E-MP), the morphology and size were characterized; while in the case of the encapsulated samples, the amount of EHMC-loading was determined. The release of EHMC was evaluated by adding EHMC-MP or EHMC + Vit.E-MP to 65% ethanol in water under mechanical stirring at 32°C. RESULTS: All MPs showed a homogeneous size distribution with a median of 90.5 ± 2.5 µm for EHMC-MP and 70.4 ± 1.14 µm for EHMC + Vit.E-MP. The encapsulation efficiency was 92.9% and 99.4% for EHMC-MP and EHMC + Vit.E-MP, respectively. The observed release from the MPs was lower than the dissolution of the pure UV filter. EHMC-MP and EHMC + Vit.E-MP were successfully incorporated into a cream formulation, with no evidence of phase separation or colour modification. Upon simulated light exposure, the photoisomerization/phototransformation of EHMC encapsulated in MPs and Vit.E-MP decreased as compared to free EHMC, both in aqueous dispersion and as a cream. The conformational ratio of the isomers (Z-/E-EHMC) was found to be the lowest in the presence of Vit.E. CONCLUSION: This work demonstrates that use of these alginate microparticulate carriers could enhance the effectiveness of sunscreen preparations containing this UVB filter.


OBJECTIF: Le filtre ultraviolet organique D'UVB 2-éthylhexyl 4-methoxycinnamate (EHMC) a été encapsulé dans des microparticules (MPs) d'alginate de sodium et co-chargé avec la vitamine E (Vit.E) par un processus d'extrusion utilisant une méthode de jet assisté aérodynamique (AAJ). L'objectif était d'évaluer l'effet de l'encapsulation concernant la libération du filtre UVB par les MPs et sa stabilité photochimique. MÉTHODES: La photostabilité EHMC a été analysée en exposant les échantillons (les deux MPs en dispersion aqueuse et incorporés dans une préparation de type crème) pendant 1 h à la lumière solaire simulée. Pour les MPs (MP-vide, EHMC-MP et EHMC - Vit.E-MP), la morphologie et la taille ont été caractérisées; tandis que dans le cas des échantillons encapsulés, la quantité de charge EHMC a été déterminée. Le relargage de l'EHMC a été évalué en ajoutant EHMC-MP ou EHMC - Vit.E-MP à 65% d'éthanol dans l'eau sous agitation mécanique à 32°C. RÉSULTATS: Tous les MP ont montré une distribution homogène de taille avec une médiane de 90,5 +- 2,5 µm pour EHMC-MP et de 70,4 +- 1,14 µm pour l'EHMC et Vit.E-MP. L'efficacité de l'encapsulation était de 92,9 % et 99,4 % pour EHMC-MP et EHMC - Vit.E-MP, respectivement. Le relargage observé des MPs était inférieur à la dissolution du filtre UV pur. EHMC-MP et EHMC - Vit.E-MP ont été incorporés avec succès dans une formulation de crème, sans aucune preuve de séparation de phase ou de modification des couleurs. Après exposition à la lumière simulée, la photoiomérisation/phototransformation de l'EHMC encapsulée dans les MPs et Vit.E-MP a diminué par rapport à l'EHMC libre, à la fois dans la dispersion aqueuse et la crème. Le rapport conformationnel des isomères (Z-/E-EHMC) s'est avéré le plus bas en présence de Vit.E.


Assuntos
Alginatos/química , Cinamatos/química , Portadores de Fármacos , Raios Ultravioleta , Composição de Medicamentos , Tamanho da Partícula
3.
J Environ Manage ; 195(Pt 2): 208-215, 2017 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-27570144

RESUMO

The photocatalytic ozonation of aniline (ANL) aqueous solutions was carried out in the presence of neat titanium dioxide (TiO2), multi-walled carbon nanotubes (MWCNT) and a composite of TiO2 and MWCNT. Independent tests for catalytic ozonation and photocatalysis were also carried out in order to explore the potential occurrence of a synergetic effect. Photocatalytic and catalytic ozonation carried out with an ozone dose of 50 g m-3 converted ANL in 15 min. Photocatalysis using P25, commercial TiO2, and an 80:20 (w/w) composite of P25 and MWCNT also led to total ANL conversion, but at longer reaction times. Removal of TOC was higher than 70% for all photocatalytic ozonation systems at 1 h of reaction. With the exception of neat MWCNT, photocatalytic ozonation in the presence of the selected samples led to nearly complete mineralization after 3 h of reaction. Photocatalytic ozonation completely removed oxalic acid (OXA) formed during ANL degradation. The concentration of oxamic acid (OMA, other ANL degradation by-product more refractory than OXA) generally increased with time, and in the photocatalytic ozonation with P25 based materials its concentration decreased earlier. The presence of nitrates and ammonium was confirmed during ANL degradation by all tested treatments, with the exception of the cation in TiO2 catalysed reactions.


Assuntos
Nanotubos de Carbono , Poluentes Químicos da Água , Compostos de Anilina , Catálise , Ácido Oxálico , Ozônio , Titânio
4.
Artigo em Inglês | MEDLINE | ID: mdl-25965513

RESUMO

In this work we present a study of the vibrational spectra of 4,5,6,8,9-pentachloropyrimido-[1,2-a][1,8]naphthyridin-10-one, C11H2Cl5N3O, a substance belonging to the important pharmacological class of 1,8-naphthyridine derivatives. The Fourier transform infrared and the Fourier transform Raman spectra of the crystal were recorded at room temperature in the regions 400-4000 and 50-4000 cm(-1), respectively. Vibrational wavenumbers were predicted using Density Functional Theory calculations with the B3LYP functional on 6-31G(d,p) and 6-311++G(d,p) basis sets. The descriptions of the normal modes were made after calculating the potential energy distribution. Additionally, potential reaction sites were evaluated through Mulliken population and Frontier Orbital analysis.


Assuntos
Naftiridinas/química , Pirimidinas/química , Halogenação , Modelos Moleculares , Conformação Molecular , Teoria Quântica , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
5.
Environ Technol ; 36(9-12): 1075-83, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25295389

RESUMO

Aniline (ANL), an aromatic amine, oxalic acid (OXA) and oxamic acid (OMA), short-chain carboxylic acids, were chosen as model organic pollutants for testing the combined effect of neat photolysis and ozonation in the treatment of aqueous effluents. In order to better understand the results, single ozonation and neat photolysis were also carried out. OXA has a high refractory character relatively to single ozonation and neat photolysis only accounted for 26% conversion of OXA after 2 h of reaction. On the other hand, OXA complete degradation was observed in less than an hour when ozone and light were used simultaneously. Despite OMA, a compound never studied before by a combined ozonation and photolysis treatment, being highly refractory to oxidation, more than 50% was removed by photo-ozonation after 3 h of reaction. In the case of ANL, both single ozonation and photo-ozonation resulted in 100% removal in a short reaction period due to the high reactivity of ozone to attack this type of molecules; however, only the combined method leads to efficient mineralization (89%) after 3 h of reaction. A significant synergetic effect was observed in the degradation of the selected contaminants by the simultaneous use of ozone and light, since the mineralization rate of combined method is higher than the sum of the mineralization rates of the individual treatments. The promising results observed in the degradation of the selected contaminants are paving the way to the application of photo-ozonation in the treatment of wastewater containing this type of pollutants.


Assuntos
Compostos de Anilina/química , Ácido Oxálico/química , Ácido Oxâmico/química , Fotólise , Poluentes Químicos da Água/química , Compostos de Anilina/efeitos da radiação , Ácido Oxálico/efeitos da radiação , Ácido Oxâmico/efeitos da radiação , Ozônio , Poluentes Químicos da Água/efeitos da radiação
6.
Arq. bras. med. vet. zootec ; 65(3): 705-709, June 2013. ilus
Artigo em Inglês | LILACS | ID: lil-679102

RESUMO

Swimmer syndrome is a developmental abnormality characterized by a delay in the ability to walk and move about and is manifested in newborns between 15 and 20 days of age. These animals exhibit constant coxofemoral articulation abduction, and their pelvic limbs move caudally and laterally. This case reports a litter of three crossbreeds kittens (26 days old) with swimmer syndrome. Each animal was treated with physical therapy and shackle bandages that kept their pelvic limbs bent and close to the body. After seven days, all of the animals exhibited normal ambulation, indicating that this treatment had a curative effect on the kittens.


A síndrome do filhote nadador é uma anormalidade do desenvolvimento caracterizada pelo atraso na capacidade de marcha e deslocamento, a qual se manifesta por volta dos 15 a 20 dias de idade. Os animais apresentam a articulação coxofemoral em constante abdução, deslocando os membros pélvicos lateral e caudalmente. Este trabalho relata uma ninhada de três filhotes felinos, sem raça definida, de 26 dias de idade, acometidos por síndrome do filhote nadador, e discute possíveis causas, complicações e tratamentos. Os filhotes foram submetidos à fisioterapia, algemas e bandagens, as quais mantiveram os membros pélvicos flexionados junto ao corpo. Ao final de sete dias, todos os filhotes apresentavam deambulação normal, e o tratamento proposto pode ser considerado curativo para felinos.


Assuntos
Animais , Gatos , Anormalidades Congênitas/genética , Atividade Motora , Gatos/classificação
7.
Vet Parasitol ; 186(3-4): 254-60, 2012 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-22130333

RESUMO

Ehrlichiosis and babesiosis are tick-borne diseases, caused mainly by Ehrlichia canis and Babesia canis, respectively, with a worldwide occurrence in dogs, whose main vector is the brown-dog tick, Rhipicephalus sanguineus. The present work aimed to detect the presence of E. canis and Babesia sp. in 91 dog blood samples in Colombia, by molecular and serological techniques. We also performed sequence alignment to indicate the identity of the parasite species infecting these animals. The present work shows the first molecular detection of E. canis and B. vogeli in dogs from Colombia. Immunoglobulin-G (IgG) antibodies to E. canis and Babesia vogeli were found in 75 (82.4%) and 47 (51.6%) sampled dogs, respectively. Thirty-seven (40.6%) and 5 (5.5%) dogs were positive in PCR for E. canis and Babesia sp., respectively. After sequencing, amplicons showed 99% of identity with isolates of E. canis and B. vogeli. The phylogenetic trees based on 16S rRNA-Anaplasmataceae sequences and 18S rRNA-piroplasmid sequences supported the identity of the found E. canis and B. vogeli DNAs, respectively. The present work shows the first molecular detection of E. canis and B. vogeli in dogs in Colombia.


Assuntos
Babesia/isolamento & purificação , Babesiose/veterinária , Doenças do Cão/diagnóstico , Ehrlichia canis/isolamento & purificação , Ehrlichiose/veterinária , Animais , Babesia/genética , Babesiose/sangue , Babesiose/epidemiologia , Colômbia/epidemiologia , Doenças do Cão/sangue , Doenças do Cão/epidemiologia , Cães , Ehrlichia canis/genética , Ehrlichiose/sangue , Ehrlichiose/epidemiologia , Filogenia , Estudos Soroepidemiológicos
8.
Rev Laryngol Otol Rhinol (Bord) ; 132(4-5): 227-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22908545

RESUMO

OBJECTIVES: The aim of this article is to illustrate the possibility of performing a cochlear implant with local anesthesia and sedation, the anesthesic technique and the advantages of that in comparison to a general anesthesia. MATERIAL AND METHODS: We describe two successful surgeries done with local anesthesia, including the neural telemetry and the conditions the patient presented after the surgery, with a very good recovery and no complications during and after the procedure. RESULTS: The results of these two surgeries are described regarding the fast recovery, no symptoms of dizziness and vomiting after the surgeries, discharging from the hospital on the same day, and the immediate post operative period by meaning of complaints from the patient. CONCLUSION: Local anesthesia with sedation for cochlear implant surgery in adults is a very good alternative for lowering the morbidity of the patient, fewer risks, lower costs for the hospital, with a very good control of the surgery.


Assuntos
Procedimentos Cirúrgicos Ambulatórios , Anestésicos Locais/uso terapêutico , Implante Coclear/métodos , Surdez/cirurgia , Lidocaína/uso terapêutico , Adulto , Surdez/etiologia , Epinefrina/uso terapêutico , Feminino , Humanos , Masculino , Otosclerose/cirurgia , Dor Pós-Operatória/tratamento farmacológico , Vasoconstritores/uso terapêutico
9.
Biomaterials ; 19(1-3): 23-9, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9678846

RESUMO

The quantification of total calcium, phosphorus, iron, chromium and nickel in cell culture medium by electrochemical or spectroscopic means may require digestion of samples. Nevertheless, when pH adjustment is performed for values higher than about 6.5, the formation of two phases occurs: a white precipitate and a clear solution. Analysing both phases using microelectrodes, atomic absorption spectrometry (AAS), diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy, X-ray dispersive (XRD) analysis, scanning electron microscopy (SEM) and energy dispersive spectroscopic (EDS) analysis, it was observed that iron, chromium and nickel are not co-precipitating with the white solid phase. If quantification of calcium, phosphorus and magnesium is intended, a ten-fold dilution at least, must be performed to avoid most of these elements going into the precipitate. This knowledge is crucial if a mineralization study is going to be made.


Assuntos
Metais/análise , Osteoblastos/química , Aço Inoxidável , Animais , Calcificação Fisiológica , Cálcio/análise , Células Cultivadas , Cromo/análise , Meios de Cultura , Eletroquímica/métodos , Concentração de Íons de Hidrogênio , Ferro/análise , Níquel/análise , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Fósforo/análise , Coelhos , Espectrofotometria Atômica
10.
Pathol Res Pract ; 187(8): 978-85, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1792194

RESUMO

The histopathology of the skin basal cell carcinomas (BCCs) with areas of intermediate differentiation (ID) has been investigated. In a series of 127 BCCs, areas of ID were found in 28 tumors (22%), and also in an additional 10 cases of other series. These areas consisted of compact masses of cells without peripheral palisading, and with intermediate differentiation between basal and squamous cells. In comparison with the common undifferentiated BCCs, the BCCs with the ID areas may behave in a more aggressive fashion, since they displayed more precocious ulceration in small tumors (p less than 0.001), greater infiltrative features (p less than 0.001), more atypical cells (p less than 0.001) with increased nuclear-cytoplasmic ratio and more mitoses (p less than 0.001). The relation of such basal cell carcinomas to the metatypical carcinoma of the skin was discussed. Metatypical carcinoma, however, has been poorly defined and thus has no general acceptance in the literature. The new definition of the basosquamous cell carcinoma and the presence of intermediate areas of differentiation in this tumor were emphasized, and it was suggested that metastatic basal cell carcinoma and metatypical carcinoma may be the same tumor.


Assuntos
Carcinoma Basocelular/patologia , Transformação Celular Neoplásica/patologia , Neoplasias Cutâneas/patologia , Carcinoma Basocelular/diagnóstico , Feminino , Humanos , Masculino , Neoplasias Cutâneas/diagnóstico
11.
Biochim Biophys Acta ; 1026(1): 133-4, 1990 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-2378877

RESUMO

This work comments on the location and orientation of 3,3'-dipropylthiodicarbocyanine (diS-C3-(5)) in renal brush-border membrane vesicles (RBBMV) (Cabrini, G. and Verkman, A.S. (1986) Biochim. Biophys. Acta 862, 285-293) evaluated from collisional quenching of n-(9-anthroyloxy)stearic acid (n-AS) fluorescence. At variance with these authors, it is concluded that the quenching is due to resonance energy transfer. It is also shown that the fluorescence data are not clear evidence for the reported monomer and dimer locations.


Assuntos
Carbocianinas/metabolismo , Rim/ultraestrutura , Microvilosidades/metabolismo , Quinolinas/metabolismo , Ácidos Esteáricos , Benzotiazóis , Fenômenos Químicos , Físico-Química , Transferência de Energia , Fluorescência , Corantes Fluorescentes , Lipossomos/metabolismo
12.
Eur J Biochem ; 189(2): 387-93, 1990 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-2338082

RESUMO

Resonance energy transfer between a local anaesthetic, dibucaine (donor) and a set of functionalized probes [n-(9-anthroyloxy)stearic acids, n = 2, 3, 6, 7, 9 and 12 and 16-(9-anthroyloxy)palmitic acid] (acceptors) was found to be an efficient process with a critical radius of transfer Ro = 2.1 nm, this interaction being used to locate the drug in a model membrane system, small unilamellar vesicles of dipalmitoylglycerophosphocholine, both above and below the temperature of the gel-to-the-liquid-crystal transition of the phospholipid. From the sequence of relative quenching efficiencies of dibucaine fluorescence upon incorporation of the probes, it was concluded that the drug intercalates in the membrane near the glycerol backbone of the lipid. In addition, it was found that dibucaine location is not significantly affected upon crossing the phase-transition temperature of the phospholipid. Dibucaine photophysics was also studied and the short lifetime of the neutral form of the anaesthetic with respect to that of the monoprotonated species was attributed to an intramolecular charge-transfer interaction. From the study of its partition coefficient between the membrane and the aqueous phase, it was concluded that the only significant species present in the membrane is the charged one.


Assuntos
1,2-Dipalmitoilfosfatidilcolina , Dibucaína , Lipossomos , Modelos Biológicos , Ácidos Palmíticos , Ácidos Esteáricos , Transferência de Energia , Teoria Quântica , Espectrometria de Fluorescência/métodos
14.
J. bras. ginecol ; 93(5): 295-8, 1983.
Artigo em Português | LILACS | ID: lil-18516

RESUMO

Estudo histologico de 100 casos de biopsias de colo uterino com a imagem macroscopica ou colposcopica de leucoplasia. A lesao tem aspectos histologicos variados e e valorizada diferentemente por diversos autores na literatura. Os quadros histologicos benignos corresponderam a 72% do total, onde predominou a hiperparaqueratose, e os 28% dos casos restantes mostraram epitelio atipico sob a forma de displasia, carcinoma in situ e carcinoma invasor. Os autores opinam que o termo leucoplasia so deve ser usado em clinica designando a lesao vista a olho nu ou ao colposcopio. A verdadeira natureza da lesao e revelada pelo exame histologico


Assuntos
Adulto , Pessoa de Meia-Idade , Humanos , Feminino , Leucoplasia , Neoplasias do Colo do Útero
15.
Med Cutan Ibero Lat Am ; 8(4-6): 109-12, 1980.
Artigo em Português | MEDLINE | ID: mdl-7024668

RESUMO

Statistic data about the incidence of cutaneous carcinoma in the region of Campinas (Sao Paulo). 1174 cutaneous cancers are reviewed. There are no differences between the localizations and distribution of the skin cancer in this regions and another countries with intense sun radiation. The preponderant localizations are the exposed areas, mainly the fronto-facial region. The author emphasizes the practical importance of the correct diagnosis of the lesions seated on the exposed areas of the skin. The convenience of early treatment of a precancer of a carcinogenic dermopathy is emphasized.


Assuntos
Carcinoma Basocelular/epidemiologia , Carcinoma de Células Escamosas/epidemiologia , Neoplasias Cutâneas/epidemiologia , Adolescente , Adulto , Fatores Etários , Idoso , Brasil , Criança , Pré-Escolar , Extremidades , Feminino , Neoplasias de Cabeça e Pescoço/epidemiologia , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Grupos Raciais , Fatores Sexuais
17.
Nephron ; 18(3): 185-8, 1977.
Artigo em Inglês | MEDLINE | ID: mdl-870846

RESUMO

A case of diffuse and bilateral necrosis of the renal medulla in an infant aged 2-1/2 months is reported. The possible causes of such severe lesion are discussed. Gastroenteritis, hypotensive state and use of a nephrotoxic drug (gentamicin) are considered to be important pathogenetical factors acting simultaneously in this patient.


Assuntos
Medula Renal/patologia , Rim/patologia , Gentamicinas/efeitos adversos , Humanos , Lactente , Medula Renal/efeitos dos fármacos , Masculino , Necrose
20.
Arq Neuropsiquiatr ; 34(1): 18031, 1976 Mar.
Artigo em Português | MEDLINE | ID: mdl-1267947

RESUMO

Central nervous system involvement in Candida septicaemia is rare and not more than four cases have been published in Brazil. Five new cases of systemic candidiasis with cerebral lesions are reported. All patients (four adults and a child) had serious underlying diseases and were submitted to heavy long-term antibiotic therapy with multiple drugs. Seizures in one case and neck stiffness in another were the only neurologic signs that could be attributed to candidiasis. In no case were the lesions severe enough to be considered an immediate cause of death. In three patients, no macroscopic changes were evident in the brain, but microabscesses and granulomata were observed on microscopical examination; another patient had two gross areas with necrotic and haemorrhagic appearance in the cerebral hemispheres; the child had only two microscopic granulomata. The aetiological agent was demonstrated by Grocott's methenamine silver technique in all cases. Involvement of organs other than the central nervous system could be demonstrated in three autopsies. Discussion is confined mainly to such aspects as the contributory factors in the pathogenesis of systemic candidiasis as well as the marked rise in the incidence of this condition in the past few decades. It is suggested that the frequence of monilial septicaemia in Brazil may be far more serious than apparent from the scarcity of reported cases.


Assuntos
Encefalopatias/microbiologia , Candidíase/diagnóstico , Adulto , Autopsia , Encefalopatias/patologia , Candidíase/patologia , Humanos , Lactente , Masculino , Pessoa de Meia-Idade
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