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1.
Indian J Dermatol ; 69(1): 74-76, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38572033

RESUMO

We retrospectively analyzed the clinical data of 1 case of disseminate and recurrent infundibular folliculitis (DRIF) in our hospital and 31 cases of DRIF reported in previous domestic and international studies. There were 32 cases, including 22 males and 10 females, with a mean age of onset of 24.72 ± 13.68 years. Skin lesions were more likely to occur on the trunk and proximal extremities and may involve the face, neck, and genitals. Typical histopathology revealed mild thickening and spongy edema of the spinous layer, different degrees of pigmentation increase in the basal layer, and mild to moderate spongy edema and inflammatory cell infiltration (predominantly lymphocytes and neutrophils) in the infundibulum and around the hair follicle. DRIF is a chronic disease more prevalent in young men of African descent and individuals with Fitzpatrick skin types 4-6. This disease is diagnosed based on clinical features and histopathology and is preferentially treated with retinoids.

3.
Membranes (Basel) ; 12(5)2022 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-35629778

RESUMO

As a kind of volatile organic compound (VOC), methyl tert-butyl ether (MTBE) is hazardous to human health and destructive to the environment if not handled properly. MTBE should be removed before the release of wastewater. The present work supported the methyl-modified silica layer (MSL) on porous α-Al2O3 ceramic membranes with methyltrimethoxysilane (MTMS) as a precursor and pre-synthesized mesoporous silica microspheres as dopants by the sol-gel reaction and dip-coating method. MTMS is an environmentally friendly agent compared to fluorinated alkylsilane. The MSL-supported Al2O3 ceramic membranes were used for MTBE/water separation by pervaporation. The NMR spectra revealed that MTMS evolves gradually from an oligomer to a highly cross-linked methyl-modified silica species. Methyl-modified silica species and pre-synthesized mesoporous silica microspheres combine into hydrophobic mesoporous MSL. MSL makes the α-Al2O3 ceramic membranes transfer from amphiphilic to hydrophobic and oleophilic. The MSL-supported α-Al2O3 ceramic membranes (MSL-10) exhibit an MTBE/water separation factor of 27.1 and a total flux of 0.448 kg m-2 h-1, which are considerably higher than those of previously reported membranes that are modified by other alkylsilanes via the post-grafting method. The mesopores within the MSL provide a pathway for the transport of MTBE molecules across the membranes. The presence of methyl groups on the external and inner surface is responsible for the favorable separation performance and the outstanding long-term stability of the MSL-supported porous α-Al2O3 ceramic membranes.

4.
Mult Scler Relat Disord ; 50: 102853, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33640847

RESUMO

BACKGROUND: Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) syndrome is an immune-mediated, treatable and inflammatory central nervous system (CNS) disease with unknown pathogenesis and polymorphic clinical and radiological manifestations. However, juxtacortical lesions have scarcely reported in patients with CLIPPERS. CASE PRESENTATION: In this study, we report 32 year old man with complaint of intermittent dizziness, disordered fluency and walking difficulties for 2 weeks. The neuroimaging revealed multiple punctuate hyperintensities on T2-weighted images, with pepper-like gadolinium enhancement in the typical lesions of brainstem, cerebellum, periventricular as well as untypical lesions of juxtacortical area. After other similar diseases were carefully ruled out, the patient was diagnosed as CLIPPERS and exhibited a good response to immunosuppressive therapy on the acute phase and after 6 months of follow up. CONCLUSIONS: The results reported here broaden the known radiologic features for this rare disorder. A long-term follow-up to rule out other potential differential diseases is essential.


Assuntos
Meios de Contraste , Imageamento por Ressonância Magnética , Adulto , China , Gadolínio , Humanos , Inflamação , Masculino , Ponte/diagnóstico por imagem
5.
Molecules ; 23(8)2018 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-30072663

RESUMO

The silica aerogels were prepared via a sol-gel technique and ambient pressure drying by using industrial solid wastes, dislodged sludges, as raw materials. A strategy was put forward to reduce the corrosion of equipment during the drying procedure. The pore structure, hydrophobicity, and thermal insulation property of the obtained samples were investigated in detail. The results show that the corrosion can be effectively avoided by using an equimolar mixture of trimethylchlorosilane (TMCS) and hexamethyldisilazane (HMDS) as silylation agents. At a Si:TMCS:HMDS molar ratio of 1:0.375:0.375, the silica aerogels possess a desirable pore structure with a pore volume of 3.3 ± 0.1 cm³/g and a most probable pore size of 18.5 nm, a high hydrophobicity with a water contact angle of 144.2 ± 1.1°, and a low thermal conductivity of 0.031 ± 0.001 W/(m∙K).


Assuntos
Dessecação , Pressão , Dióxido de Silício/síntese química , Adsorção , Corrosão , Fluorescência , Interações Hidrofóbicas e Hidrofílicas , Espectroscopia de Ressonância Magnética , Nitrogênio/química , Porosidade , Dióxido de Silício/química , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Condutividade Térmica , Volatilização , Difração de Raios X
6.
Bing Du Xue Bao ; 31(4): 420-4, 2015 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-26524915

RESUMO

We wished to assess the role of chlamydia micro virus capsid protein Vp3 in recombinant molecules, chart its molecular evolution, screen the wild-type strain, and reveal its value in clinical research. Using a protein BLAST multiple-alignment program, we compared various strains of Chlamydia micro virus capsid protein Vp3 sequences. Using a "distance tree" of those results, we created a phylogenetic tree. We applied the Karplus-Schulz method of flexible-region analyses for highly conserved alignments of amino-acid sequences. Gamier-Robson and Chou-Fasman methods were employed to analyze two-level structures of sequences. The Emini method was used for analyses of the accessibility of surface epitopes. Studies of hydrophilic proteins were undertaken using Kyte-Doolittle and Hopp-Woods methods. Analyses of antigen epitopes helped to reveal the antigen index using the Jameson-Wolf method. All sequences in the six strains of chlamydia micro virus capsid protein Vp3 were highly conserved, with the main differences being between Vp3 protein in Chp1 and the other five strains of the micro virus. The viral strain of Vp3 protein was based mainly on micro-alpha helix structures, and multiple epitopes were noted in highly conserved regions. Vp3 protein was highly conserved structurally, and was an important protein of the chlamydiaphage capsid. Vp3 protein has a complicated molecular structure, highly conserved regions with strong immunogenicity, and has considerable research value.


Assuntos
Proteínas do Capsídeo/química , Proteínas do Capsídeo/imunologia , Chlamydia/imunologia , Sequência de Aminoácidos , Proteínas do Capsídeo/genética , Chlamydia/genética , Sequência Conservada , Mapeamento de Epitopos , Evolução Molecular , Dados de Sequência Molecular , Recombinação Genética
7.
J Colloid Interface Sci ; 346(1): 61-5, 2010 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-20227713

RESUMO

Large pore ordered mesoporous organosilicas (OMOs) with distinct mesophase structure was synthesized under low temperatures by the co-condensation of 1,2bis(triethoxysilyl)ethane (BTESE) and tetraethyl orthosilicate (TEOS) in acidic solution, using triblock copolymer F127 as a template and 1,3,5-trimethylbenzene (TMB) as a swelling agent. With the decrease of temperature, a mesophase transformation from 2D hexagonal structure (p6mm) via mesostructured cellular foam to a highly ordered 3D cubic structure (Fm3m) was evidenced by small angle X-ray diffraction (SAXS), transmission electron microscopy (TEM) and N(2) sorption. It reveals that the lower synthesis temperatures may influence the hydrolysis and condensation of silica species and the hydrophilic-hydrophobic property of F127, as well as the swelling capacity of F127 micelles with TMB, which resulting in a formation of large pores ordered mesoporous organosilicas with various mesostructures materials. Finally, the enzyme adsorption properties of the OMOs were investigated and the results showed that the OMOs with a 3D large pore structure and regular morphology is much more qualified for enzyme adsorption.


Assuntos
Compostos de Organossilício/química , Compostos de Organossilício/síntese química , Papaína/química , Adsorção , Interações Hidrofóbicas e Hidrofílicas , Papaína/metabolismo , Tamanho da Partícula , Polietilenos/química , Polipropilenos/química , Porosidade , Propriedades de Superfície , Temperatura
8.
J Phys Chem B ; 112(31): 9354-9, 2008 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-18613718

RESUMO

Fluorocarbon-modified silica membranes were deposited on gamma-Al2O3/alpha-Al2O3 supports by the sol-gel technique for hydrogen separation. The hydrophobic property, pore structure, gas transport and separation performance, and hydrothermal stability of the modified membranes were investigated. It is observed that the water contact angle increases from 27.2+/-1.5 degrees for the pure silica membranes to 115.0+/-1.2 degrees for the modified ones with a (trifluoropropyl)triethoxysilane (TFPTES)/tetraethyl orthosilicate (TEOS) molar ratio of 0.6. The modified membranes preserve a microporous structure with a micropore volume of 0.14 cm3/g and a pore size of approximately 0.5 nm. A single gas permeation of H2 and CO2 through the modified membranes presents small positive apparent thermal activation energies, indicating a dominant microporous membrane transport. At 200 degrees C, a single H2 permeance of 3.1x10(-6) mol m(-2) s(-1) Pa(-1) and a H2/CO2 permselectivity of 15.2 were obtained after proper correction for the support resistance and the contribution from the defects. In the gas mixture measurement, the H2 permeance and the H2/CO2 separation factor almost remain constant at 200 degrees C with a water vapor pressure of 1.2x10(4) Pa for at least 220 h, indicating that the modified membranes are hydrothermally stable, benefiting from the integrity of the microporous structure due to the fluorocarbon modification.

9.
J Colloid Interface Sci ; 261(2): 325-9, 2003 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-16256538

RESUMO

Nearly monodisperse SiO2/TiO2/SiO2 multiply coated submicrospheres with nearly monodisperse silica submicrospheres as cores, thick titania layers, and thin silica skin were prepared to increase the refractive index of complex submicrospheres while keeping their near monodispersity and perfect surface properties. Nearly monodisperse colloidal silica submicrospheres as cores with a diameter of 200 nm were synthesized by a seeding technique on the basis of the hydrolysis of tetraethyl orthosilicate (TEOS) in an aqueous ethanol solution with ammonia as catalyst. On the basis of the hydrolysis of tetrabutyl orthotitanate, a procedure combining continuous feeding with multistep coating was determined to prepare titania coatings about 40 nm thick and increase the refractive index of the complex submicrospheres. The hydrolysis of TEOS was still used to get the outmost silica coating about 10 nm thick on titania coated silica submicrospheres to eliminate random aggregation caused by the TiO2 surface properties of the TiO2/SiO2 complex submicrospheres during the final fabrication of photonic crystals.

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