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1.
Acta Neurochir (Wien) ; 159(7): 1237-1240, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28236182

RESUMO

BACKGROUND: Despite considerable advances in preoperative and intraoperative imaging and neuronavigation, resection of thalamic gliomas remains challenging. Although both endoscopic biopsy and third ventriculostomy (ETV) for the treatment of secondary hydrocephalus are commonly performed, endoscopic resection of thalamic gliomas has been very sparsely described. METHOD: We report and illustrate the surgical procedure and patient's outcome after full endoscopic resection of a thalamic glioma and to discuss this approach as an alternative to open microsurgery. RESULTS: In 2016, a 56-year-old woman presented with disorientation, dysphasia and right facial hypaesthesia in our department. Cranial magnetic resonance imaging revealed a left thalamic lesion and subsequent hydrocephalus. Initially, hydrocephalus was treated by ETV but forceps biopsy was not diagnostic. However, metabolism in 18F-fluoroethyl-L-tyrosine positron emission tomography indicated glioma. Subsequently, endoscopic and neuronavigation-guided tumour resection was performed using a <1 cm2, trans-sulcal approach through the left posterior horn of the lateral ventricle. While visibility was poor using the intraoperative microscope, neuroendoscopy provided excellent visualisation and allowed safe tumour debulking. Neither haemorrhage from the tumour or collapse of the cavity compromised endoscopic resection. CONCLUSIONS: In accordance with one previously published case of endoscopic resection of a thalamic glioma, no surgery-related complications were observed. Although this remains to be determined in larger series, endoscopic resection of these lesions might be a safe and feasible alternative to biopsy or open surgery. Future studies should also aim to identify patients specifically eligible for these approaches.


Assuntos
Neoplasias Encefálicas/cirurgia , Glioma/cirurgia , Microcirurgia/efeitos adversos , Neuroendoscopia/métodos , Tálamo/cirurgia , Ventriculostomia/métodos , Neoplasias Encefálicas/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Microcirurgia/métodos , Pessoa de Meia-Idade , Neuroendoscopia/efeitos adversos , Neuronavegação/efeitos adversos , Neuronavegação/métodos , Complicações Pós-Operatórias , Tálamo/patologia , Terceiro Ventrículo/cirurgia , Ventriculostomia/efeitos adversos
2.
J Chem Phys ; 144(16): 164305, 2016 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-27131548

RESUMO

Experimental and theoretical double differential cross sections (DDCSs) for electron-induced ionization of methane (CH4) are here reported for primary energies ranging from 50 eV to 350 eV and ejection angles between 25° and 130°. Experimental DDCSs are compared with theoretical predictions performed within the first Born approximation Coulomb wave. In this model, the initial molecular state is described by using single center wave functions, the incident (scattered) electron being described by a plane wave, while a Coulomb wave function is used for modeling the secondary ejected electron. A fairly good agreement may be observed between theory and experiment with nevertheless an expected systematic overestimation of the theory at low-ejection energies (<50 eV).

3.
Phys Chem Chem Phys ; 17(26): 17288-95, 2015 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-26073634

RESUMO

Mixed-anion materials for Li-ion batteries have been attracting attention in view of their tunable electrochemical properties. Herein, we compare two isostructural (Fm3̅m) model intercalation materials Li2VO3 and Li2VO2F with O(2-) and mixed O(2-)/F(-) anions, respectively. Synchrotron X-ray diffraction and pair distribution function data confirm large structural similarity over long-range and at the atomic scale for these materials. However, they show distinct electrochemical properties and kinetic behaviour arising from the different anion environments and the consequent difference in cationic electrostatic repulsion. In comparison with Li2VO3 with an active V(4+/5+) redox reaction, the material Li2VO2F with oxofluoro anions and the partial activity of V(3+/5+) redox reaction favor higher theoretical capacity (460 mA h g(-1)vs. 230 mA h g(-1)), higher voltage (2.5 V vs. 2.2 V), lower polarization (0.1 V vs. 0.3 V) and faster Li(+) chemical diffusion (∼10(-9) cm(2) s(-1)vs. ∼10(-11) cm(2) s(-1)). This work not only provides insights into the understanding of anion chemistry, but also suggests the rational design of new mixed-anion battery materials.

4.
Phys Chem Chem Phys ; 17(2): 1482-8, 2015 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-25431932

RESUMO

Intercalation pseudocapacitive Li(+) storage has been recognized recently in metal oxide materials, wherein Li(+) intercalation into the lattice is not solid-state diffusion-limited. This may bridge the performance gap between electrochemical capacitors and battery materials. To date, only a few materials with desired crystal structure and with well-defined nanoarchitectures have been found to exhibit such attractive behaviour. Herein, we report for the first time that nanoscale spinel LiFeTiO4 as a cathode material for Li-ion batteries exhibits intercalation pseudocapacitive Li(+) storage behaviour. Nanoscale LiFeTiO4 nanoparticles with native carbon coating were synthesized by a sol-gel route. A fast and large-amount of Li(+) storage (up to 1.6 Li(+) per formula unit over cycling) in the nanoscale LiFeTiO4 host has been achieved without compromising kinetics.

5.
World Neurosurg ; 129: e857-e865, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31300351

RESUMO

BACKGROUND: Foraminal cervical nerve root compression can be caused by lateral disk herniation or osteophyte formation of the vertebrae. Improved diagnosis and evaluation can be achieved using different imaging techniques: radiographs, computed tomography (CT), and magnetic resonance imaging. We retrospectively evaluated the potential influence of a virtual reality (VR) visualization technique on surgery planning and evaluation of postoperative results in patients with monosegmental, unilateral osseous cervical neuroforaminal stenosis. METHODS: Seventy-three patients were included. Ventral decompression of the neuroforamen was performed in 41 patients, dorsal decompression in 32 patients. Patients' files were evaluated. CT scans were visualized via VR software to measure the smallest cross-sectional area of the intervertebral neuroforamen in the lateral resection region. A questionnaire evaluated the influence of VR technique on surgical planning and strategy. RESULTS: The VR-technique had a moderate influence on the choice of the approach (ventral or dorsal), a significant influence on the ventral approach strategy, and no influence on the positioning of the patient or the dorsal approach strategy. A significant difference was found in the size of the smallest cross-sectional area of the intervertebral neuroforamen in the lateral resection region between ventral and dorsal approaches, with no correlation to the clinical outcome. CONCLUSIONS: Reconstruction of pre- and postoperative 2D-CT images of the cervical spine into 3D images, and the spatial and anatomical reconstructions in VR models, can be helpful in planning surgical approaches and treatment strategies for patients with cervical foraminal stenoses, and for evaluation of their postoperative results.


Assuntos
Descompressão Cirúrgica/métodos , Neuroimagem/métodos , Radiculopatia/cirurgia , Cirurgia Assistida por Computador/métodos , Realidade Virtual , Adulto , Idoso , Vértebras Cervicais/diagnóstico por imagem , Feminino , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Masculino , Pessoa de Meia-Idade , Radiculopatia/diagnóstico por imagem , Tomografia Computadorizada por Raios X
6.
Nat Commun ; 10(1): 5365, 2019 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-31772159

RESUMO

One major challenge in the field of lithium-ion batteries is to understand the degradation mechanism of high-energy lithium- and manganese-rich layered cathode materials. Although they can deliver 30 % excess capacity compared with today's commercially- used cathodes, the so-called voltage decay has been restricting their practical application. In order to unravel the nature of this phenomenon, we have investigated systematically the structural and compositional dependence of manganese-rich lithium insertion compounds on the lithium content provided during synthesis. Structural, electronic and electrochemical characterizations of LixNi0.2Mn0.6Oy with a wide range of lithium contents (0.00 ≤ x ≤ 1.52, 1.07 ≤ y < 2.4) and an analysis of the complexity in the synthesis pathways of monoclinic-layered Li[Li0.2Ni0.2Mn0.6]O2 oxide provide insight into the underlying processes that cause voltage fading in these cathode materials, i.e. transformation of the lithium-rich layered phase to a lithium-poor spinel phase via an intermediate lithium-containing rock-salt phase with release of lithium/oxygen.

7.
Brain Res ; 1156: 21-30, 2007 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-17512503

RESUMO

Both maternal protein malnutrition and intrauterine growth restriction (IUGR) have deleterious effects on brain development, but a comparison of these effects has not been previously reported. The objectives of this study were to investigate and compare the effects of both factors on the oxidative status of the central nervous system (CNS), including the spinal cord, in offspring rats. We evaluated various parameters of oxidative status and antioxidant enzyme activities of superoxide dismutase and catalase (CAT) in different regions of the CNS from 60-day-old rats subjected to prenatal and postnatal protein restrictions [middle protein restriction 12%, severe protein restriction (SPR) 4%] or IUGR produced by uterine artery ligation. Furthermore, we compared these study groups to each other and to control rats fed an isocaloric 24% protein diet. Results were analyzed using one-way ANOVA followed by Tukey's post hoc test. Both protein restrictions and IUGR altered various parameters of oxidative status. In all evaluated structures, protein restrictions resulted in increases in thiobarbituric acid-reactive substances level and index of lipid peroxidation (P<0.001), and in decreases in antioxidant enzyme activities (P<0.005). IUGR also increased lipid peroxidation levels in the blood samples (P<0.04) and protein oxidative damage in the cerebellum and cerebral cortex (P<0.005); however, no effects were detected on the spinal cord. The greatest decrease in CAT activity was in the cerebellum of rats fed with SPR diet (P<0.001). This study suggests that not only severe but also middle protein malnutrition have deleterious effects on CNS structures, including the spinal cord. Protein restriction has a greater effect on the redox state of the CNS than IUGR.


Assuntos
Encéfalo/enzimologia , Retardo do Crescimento Fetal/etiologia , Complicações na Gravidez/fisiopatologia , Desnutrição Proteico-Calórica/fisiopatologia , Superóxido Dismutase/metabolismo , Envelhecimento , Animais , Peso Corporal , Encéfalo/crescimento & desenvolvimento , Catalase/metabolismo , Feminino , Tamanho do Órgão , Oxirredução , Gravidez , Ratos
8.
Colloids Surf B Biointerfaces ; 133: 73-80, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26087391

RESUMO

The reported studies related to black seed oil (BSO) and wheat germ oil (WGO) have illustrated that they have a wide range of biological activities. Therefore, enhancing the amount of bio-active compounds that caused higher cell based anti-oxidative effect as well as cell proliferation, etc. in seed oils, infusion of crude plant material has been gained importance as a traditional technique. Herein, we accomplished the infusion of Calendula flowers that also contains many phyto-constituents into BSO and WGO. After the infusion of oils, the change of phytochemical amount was investigated and evaluated according to the oils by chromatography, radical scavenging activity. Subsequently, for investigating the biological impact upon live cells, cytotoxicity, cell-based antioxidant capacity, wound healing and radioprotective activity were tested with monkey kidney fibroblast like cells (Vero) and HaCaT keratinocytes. In vitro cell based experiments (wound healing and radioprotective activity) confirmed that Calendula infused BSO and WGO have greater bio-activity when compared to those plain forms. The herbal oils prepared with an effective extraction technique were incorporated into nanoemulsion systems which will be then called as 'Phyto-Nanoemulsion'. After herbal oil biomolecules were encapsulated into nanoemulsion based delivery systems, the designed formulations were investigated in terms of biological activities. In conclusion, these preparations could be a good candidate as a part of dermal cosmetic products or food supplements which have the therapeutic efficiency, especially after radio- or chemotherapy.


Assuntos
Emulsões , Medicina Herbária , Nanotecnologia , Óleos de Plantas/administração & dosagem , Animais , Linhagem Celular , Chlorocebus aethiops , Humanos , Técnicas In Vitro , Óleos de Plantas/química , Células Vero
9.
Prikl Biokhim Mikrobiol ; 38(2): 166-8, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-11962214

RESUMO

The antimicrobial activity of the ethanol extract of resins obtained from the roots and stems of Cedrus libani and Abies cilicica was investigated using a disc diffusion method. Results revealed that crude extracts of the resins of both plants are highly effective against tested microorganisms by preventing their growth to a greater extent.


Assuntos
Abies/química , Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Cedrus/química , Resinas Vegetais/farmacologia , Antibacterianos , Antifúngicos/farmacologia , Bactérias/crescimento & desenvolvimento , Candida albicans/crescimento & desenvolvimento , Humanos , Testes de Sensibilidade Microbiana , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Caules de Planta/química
10.
Artigo em Inglês | MEDLINE | ID: mdl-25280673

RESUMO

A conformationally rigid half-sandwich organoruthenium (II) complex [(η(6)-p-cymene)RuClTSC(N-S)]Cl, (1) and carbonyl complex [Ru(CO)Cl(PPh3)2TSC(N-S)] (2) have been synthesized from the reaction of [{(η(6)-p-cymene)RuCl}2(µ-Cl)2] and [Ru(H)(Cl)(CO)(PPh3)3] with thiophene-2-carboxaldehyde thiosemicarbazon (TSC) respectively and both novel ruthenium (II) complexes have been characterized by elemental analysis, FT-IR and NMR spectroscopy. The peripheral TSC in the complexes acts as an electrochemical coupling unit providing the ability to carry out electrochemical deposition (ED) and to form an electro-deposited film on a graphite electrode surface. The biosensing applicability of complexes 1 and 2 was investigated by using glucose oxidase (GOx) as a model enzyme. Electrochemical measurements at -0.9V versus Ag/AgCl electrode by following the ED Ru(II) reduction/oxidation due to from the enzyme activity, in the presence of glucose substrate. The designed biosensor showed a very good linearity for 0.01-0.5mM glucose. The in vitro antimicrobial activities of complexes 1 and 2 were also investigated against nine bacterial strains and one fungus by the disc diffusion test method. No activity was observed against the Gram-negative strains and fungus, whereas complex 1 showed moderate antibacterial activities against Gram-positive bacterial strains.


Assuntos
Antibacterianos/química , Antifúngicos/química , Técnicas Biossensoriais , Rutênio/química , Tiossemicarbazonas/química , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Técnicas Eletroquímicas , Fungos/efeitos dos fármacos , Glucose Oxidase/química , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Conformação Molecular , Espectroscopia de Infravermelho com Transformada de Fourier
11.
Colloids Surf B Biointerfaces ; 121: 299-306, 2014 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-25009101

RESUMO

A novel and efficient approach for the preparation of enriched herbal formulations was described and their potential applications including wound healing and antioxidant activity (cell based and cell free) were investigated via in vitro cell culture studies. Nigella sativa oil was enriched with Calendula officinalis extract and lipoic acid capped gold nanoparticles (AuNP-LA) using nanoemulsion systems. The combination of these bio-active compounds was used to design oil in water (O/W) and water in oil (W/O) emulsions. The resulted emulsions were characterized by particle size measurements. The phenolic content of each nanoemulsion was examined by using both colorimetric assay and chromatographic analyses. Two different methods containing cell free chemical assay (1-diphenyl-2-picrylhydrazyl method) and cell based antioxidant activity test were used to evaluate the antioxidant capacities. In order to investigate the bio-activities of the herbal formulations, in vitro cell culture experiments, including cytotoxicity, scratch assay, antioxidant activity and cell proliferation were carried out using Vero cell line as a model cell line. Furthermore, to monitor localization of the nanoemulsions after application of the cell culture, the cell images were monitored via fluorescence microscope after FITC labeling. All data confirmed that the enriched N. sativa formulations exhibited better antioxidant and wound healing activity than N. sativa emulsion without any enrichment. In conclusion, the incorporation of AuNP-LA and C. officinalis extract into the N. sativa emulsions significantly increased the bio-activities. The present work may support further studies about using the other bio-active agents for the enrichment of herbal preparations to strengthen their activities.


Assuntos
Materiais Biocompatíveis/farmacologia , Calendula/química , Emulsões/química , Ouro/química , Nanopartículas Metálicas/química , Extratos Vegetais/farmacologia , Ácido Tióctico/farmacologia , Animais , Antioxidantes/metabolismo , Benzoquinonas/metabolismo , Compostos de Bifenilo/metabolismo , Proliferação de Células/efeitos dos fármacos , Chlorocebus aethiops , Cromatografia Líquida de Alta Pressão , Peróxido de Hidrogênio/toxicidade , Microscopia de Fluorescência , Fenóis/análise , Picratos/metabolismo , Óleos de Plantas , Células Vero , Cicatrização/efeitos dos fármacos
12.
J Food Sci ; 78(2): E238-43, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23331176

RESUMO

The objective of this study was to determine ß-casein adsorption by using supermacroporous poly(2-hydroxyethyl methacrylate-N-methacryloyl-(l)-histidine methyl ester) [p(HEMA-MAH)] cryogel. ß-Casein adsorption properties of p(HEMA-MAH) cryogel were studied for the application of ß-casein purification. The cryogel was produced by free radical polymerization initiated by N,N,N',N'-tetramethylene diamine and ammonium persulfate pairs in an ice bath. P(HEMA-MAH) cryogel was characterized by swelling tests, Fourier transform infrared spectroscopy, and scanning electron microscopy. The effects of the flow rate, pH, temperature, initial ß-casein concentration, and ionic strength on the adsorption efficiency of cryogel were studied. The equilibrium swelling degree of the p(HEMA-MAH) cryogel was 6.73 g H(2) O/g cryogel. ß-Casein adsorption capacity of p(HEMA-MAH) cryogel from aqueous solution was estimated as 31.17 mg/g cryogel. It was also observed that ß-casein could be repeatedly adsorbed and desorbed with p(HEMA-MAH) cryogel without significant loss in the adsorption capacity.


Assuntos
Caseínas/química , Criogéis/química , Histidina/análise , Poli-Hidroxietil Metacrilato/química , Adsorção , Sulfato de Amônio/química , Criogéis/análise , Histidina/análogos & derivados , Histidina/química , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Concentração Osmolar , Polimerização , Putrescina/química , Temperatura
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