Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 27
Filtrar
1.
Adv Sci (Weinh) ; 11(22): e2309869, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38544479

RESUMO

Ruthenium (Ru) is a promising electrocatalyst for the hydrogen evolution reaction (HER), despite suffering from low activity in non-acidic conditions due to the high kinetic energy barrier of H2O dissociation. Herein, the synthesis of carbon nanosheet-supported RuP/Ru heterostructures (RuP/Ru@CNS) from a natural polysaccharide is reported and demonstrates its behavior as an effective HER electrocatalyst in non-acidic conditions. The RuP/Ru@CNS exhibits low overpotential (106 mV at 200 mA·cm-2) in alkaline electrolyte, exceeding most reported Ru-based electrocatalysts. The electron shuttling between Ru atoms at the RuP/Ru interface results in a lowered energy barrier for H2O dissociation by electron-deficient Ru atoms in the pure Ru phase, as well as optimized H* adsorption of electron-gaining Ru atoms in the neighboring RuP. A low H* spillover energy barrier between Ru atoms at the RuP/Ru interface further boosts HER kinetics. This study demonstrates a sustainable method for the fabrication of efficient Ru-based electrocatalysts and provides a more detailed understanding of interface effects in HER catalysis.

2.
Small ; 20(25): e2307986, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38189535

RESUMO

The volume collapse and slow kinetics reaction of anode materials are two key issues for sodium ion batteries (SIBs). Herein, an "embryo" strategy is proposed for synthesis of nanorod-embedded MoO2/MoS2/C network nanoarchitecture as anode for SIBs with high-rate performance. Interestingly, L-cysteine which plays triple roles including sulfur source, reductant, and carbon source can be utilized to produce the sulfur vacancy-enriched heterostructure. Specifically, L-cysteine can combine with metastable monoclinic MoO3 nanorods at room temperature to encapsulate the "nutrient" of MoOx analogues (MoO2.5(OH)0.5 and MoO3·0.5H2O) and hydrogen-deficient L-cysteine in the "embryo" precursor affording for subsequent in situ multistep heating treatment. The resultant MoO2/MoS2/C presents a high-rate capability of 875 and 420 mAh g-1 at 0.5 and 10 A g-1, respectively, which are much better than the MoS2-based anode materials reported by far. Finite element simulation and analysis results verify that the volume expansion can be reduced to 42.8% from 88.8% when building nanorod-embedded porous network structure. Theoretical calculations reveal that the sulfur vacancies and heterointerface engineering can promote the adsorption and migration of Na+ leading to highly enhanced thermodynamic and kinetic reaction. The work provides an efficient approach to develop advanced electrode materials for energy storage.

3.
Nano Lett ; 24(2): 592-600, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38039420

RESUMO

Engineering of the catalysts' structural stability and electronic structure could enable high-throughput H2 production over electrocatalytic water splitting. Herein, a double-shell interlayer confinement strategy is proposed to modulate the spatial position of Ru nanoparticles in hollow carbon nanoreactors for achieving tunable sizes and electronic structures toward enhanced H2 evolution. Specifically, the Ru can be anchored in either the inner layer (Ru-DSC-I) or the external shell (Ru-DSC-E) of double-shell nanoreactors, and the size of Ru is reduced from 2.2 to 0.9 nm because of the double-shell confinement effect. The electronic structures are efficiently optimized thereby stabilizing active sites and lowering the reaction barrier. According to finite element analysis results, the mesoscale mass diffusion can be promoted in the double-shell configuration. The Ru-DSC-I nanoreactor exhibits a much lower overpotential (η10 = 73.5 mV) and much higher stability (100 mA cm-2). Our work might shed light on the precise design of multishell catalysts with efficient refining electrostructures toward electrosynthesis applications.

4.
Angew Chem Int Ed Engl ; 62(40): e202308091, 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37340794

RESUMO

The coordination structure determines the electrocatalytic performances of single atom catalysts (SACs), while it remains a challenge to precisely regulate their spatial location and coordination environment. Herein, we report a universal sub-nanoreactor strategy for synthesis of yolk-shell MoS2 supported single atom electrocatalysts with dual-anchored microenvironment of vacancy-enriched MoS2 and intercalation carbon toward robust hydrogen-evolution reaction. Theoretical calculations reveal that the "E-Lock" and "E-Channel" are conducive to stabilize and activate metal single atoms. A group of SACs is subsequently produced with the assistance of sulfur vacancy and intercalation carbon in the yolk-shell sub-nanoreactor. The optimized C-Co-MoS2 yields the lowest overpotential (η10 =17 mV) compared with previously reported MoS2 -based electrocatalysts to date, and also affords a 5-9 fold improvement in activity even comparing with those as-prepared single-anchored analogues. Theoretical results and in situ characterizations unveil its active center and durability. This work provides a universal pathway to design efficient catalysts for electro-refinery.

5.
J Neurosurg ; 139(5): 1376-1385, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37243560

RESUMO

OBJECTIVE: Personalized stimulation is key to optimizing the outcomes of deep brain stimulation (DBS) for refractory obsessive-compulsive disorder (OCD). However, the contacts in a single conventional electrode cannot be programmed independently, which may affect the therapeutic efficacy of DBS for OCD. Therefore, a novel designed electrode and implantable pulse generator (IPG) that could achieve differential stimulation parameters for different contacts was implanted into the nucleus accumbens (NAc) and anterior limb of the internal capsule (ALIC) of a cohort of patients with OCD. METHODS: Thirteen consecutive patients underwent bilateral DBS of the NAc-ALIC between January 2016 and May 2021. Differential stimulation of the NAc-ALIC was applied at initial activation. Primary effectiveness was assessed on the basis of change in scores on the Yale-Brown Obsessive Compulsive Scale (Y-BOCS) from baseline to 6-month follow-up. Full-response was defined as a 35% decrease in Y-BOCS score. Secondary effectiveness measures were the Hamilton Anxiety Rating Scale (HAMA) and Hamilton Depression Rating Scale (HAMD). The local field potential of bilateral NAc-ALIC was recorded in 4 patients who were reimplanted with a sensing IPG after battery depletion of the previous IPG. RESULTS: The Y-BOCS, HAMA, and HAMD scores decreased remarkably during the first 6 months of DBS. Ten of 13 patients were categorized as responders (76.9%). Differential stimulation of the NAc-ALIC was favorable to optimization of the stimulation parameters by increasing the parameter configurations. Power spectral density analysis revealed pronounced delta-alpha frequency activity in the NAc-ALIC. Phase-amplitude coupling of the NAc-ALIC showed that strong coupling is present between the phase of delta-theta and broadband gamma amplitude. CONCLUSIONS: These preliminary findings indicate that differential stimulation of the NAc-ALIC can improve the efficacy of DBS for OCD. Clinical trial registration no.: NCT02398318 (ClinicalTrials.gov).


Assuntos
Estimulação Encefálica Profunda , Transtorno Obsessivo-Compulsivo , Humanos , Núcleo Accumbens , Cápsula Interna , Transtorno Obsessivo-Compulsivo/terapia , Eletrodos , Resultado do Tratamento
6.
Phys Chem Chem Phys ; 24(46): 28530-28539, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36411969

RESUMO

Metal oxide sensors face the challenge of high response and fast recovery at low operating temperatures for the detection of toxic and flammable hydrogen sulfide (H2S) gases. Herein, novel In-doped ZnO with a sunflower-like structure and tunable surface properties was rationally synthesized. The substitutional In atom in the ZnO crystal can dramatically enhance the concentration of oxygen vacancies (Ov), the In-ZnO sites are responsible for fast recovery, and the formation of sub-stable sulfide intermediates gives rise to the high response towards H2S. As a result, the response of the optimized 4In-ZnO sensor is 3538.36 to 50 ppm H2S at a low operating temperature of 110 °C, which is 106 times higher than that of pristine ZnO. Moreover, the response time and recovery time to 50 ppm H2S are 100 s and 27 s, respectively, with high selectivity and stability. First-principles calculations revealed that 4In-ZnO with rich Ov exhibited higher adsorption energy for the H2S molecule than pristine ZnO, resulting in effortless H2S detection. Our work lays the foundation for the rational design of highly sensitive gas sensors through precise doping of atoms in oxygen-rich vacancies in semiconductor materials.

7.
Dalton Trans ; 51(25): 9622-9626, 2022 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-35697302

RESUMO

In the preparation of Prussian blue analogs (PBAs), Na+ loss and Fe2+ oxidation take place when washing with water. Sodium-rich PBAs were prepared with sodium ascorbate aqueous solution as the washing solution, which can suppress the Na+ loss and Fe2+ oxidation. As the cathode of sodium-ion batteries, it exhibited excellent electrochemical performance.

8.
Animals (Basel) ; 12(9)2022 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-35565528

RESUMO

In July 2021, a disease with a high mortality rate broke out in freshwater cultured hybrid sturgeon in Zhengzhou, Henan Province. A dominant strain, H-701, was isolated from diseased fish; physiological changes in diseased fish were investigated and molecular identification, biochemical characterization, and pathogenicity and drug sensitivity tests of H-701 were performed. The 16S rRNA gene sequence of H-701 was 99.86% homologous with that of Vibrio metschnikovii in GenBank. The 50% lethal dose of H-701 was 3.72 ± 0.929 × 104 CFU/g fish weight. The proportion of monocytes, neutrophils, and eosinophils in the blood of diseased sturgeon increased significantly, whereas the proportion of lymphocytes decreased. In diseased fish, the serum levels of total protein, albumin, globulin, and alkaline phosphatase decreased significantly, and those of aspartate aminotransferase, alanine aminotransferase, and complement C3 increased significantly. There were obvious pathological changes in several tissues of the diseased fish. H-701 was sensitive to antibiotics such as florfenicol, enrofloxacin, and doxycycline. This study not only demonstrated that V. metschnikovii was the cause of death of a large number of hybrid sturgeon but also revealed its potential risk in hybrid sturgeon aquaculture. The results provide a basis for the diagnosis and prevention of this disease.

9.
Nanoscale ; 13(5): 3027-3035, 2021 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-33514980

RESUMO

Enabling stable lithium metal anodes is significant for developing electrochemical energy storage systems with higher energy density. However, safety hazards, infinite volume expansion, and low coulombic efficiency (CE) of lithium metal anodes always hinder their practical application. Herein, a nano-thickness lithiophilic Cu-Ni bimetallic coating was synthesized to prepare dendrite-free lithium metal anodes. The electron cloud migration effect caused by the different electronegativities of Cu and Ni can achieve lithiophobicity/lithiophilicity transformation and thus promote uniform Li deposition/dissolution. By changing the ratio of Cu to Ni, the electron cloud migration can be reasonably adjusted for obtaining dendrite-free lithium anodes. As a result, the as-obtained Cu-Ni bimetallic coating is able to guarantee dendrite-free lithium metal anodes with a stable long cycling time (>1500 hours) and a small voltage hysteresis (∼26 mV). In addition, full cells with LiFePO4 as a cathode present excellent cycling stability and high coulombic efficiency. This work can open a new avenue for optimizing the lithiophilicity of materials and realizing dendrite-free anodes.

10.
Chem Rec ; 20(12): 1553-1567, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33021040

RESUMO

Gas sensors based on metal oxides semiconductor (MOS) have attracted extensive attention from both academic and industry. ZnO, as a typical MOS, exhibits potential applications in toxic gas detection, owning to its wide band gap, n-type transport characteristic and excellent electrical performance. Meanwhile, doping is an effective way to improve the sensing performance of ZnO materials. In this review, the effects of different types of doping on morphology, crystal structure, band gap and depletion layer of ZnO materials are comprehensively discussed. Theoretical analysis on the strategies for enhancing the sensing properties of ZnO is also provided. This review puts forward the reasonable insight for designing efficient n-type ZnO-based semiconductor oxide sensing materials.

11.
J Hazard Mater ; 388: 122069, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-31954308

RESUMO

Aniline detection is of great importance in many industries, but most of the aniline sensors suffers from tedious and time consuming process. Herein, we present an efficient aniline sensor based on Pd decorated ZnO nanomaterials. Ultrathin ZnO nanosheets were synthesized by a facile one-step hydrothermal method. The nanosheets were corrugated into a unique agaric morphology, endorsing the nanomaterials with high surface area that is ideal for gas sensing applications. The obtained ZnO nanosheets were then uniformly decorated with uniform Pd nanoparticles (Pd NPs) around 5 nm in diameter. Gas sensing experiment on the ZnO decorate with different amount of Pd nanoparticles were systematically evaluated. The sample decorated with 0.3 % Pd NPs (Pd-ZnO-0.3) exhibited the highest sensitivity to aniline, which is about two orders higher than that of the pure ZnO nanosheet. The gas sensor based on Pd-ZnO-0.3 has a detection limit to aniline down to 0.5 ppm, with very short response and recovery times of 29 s and 23 s, respectively to 100 ppm aniline. First-principles DFT study was employed to provide the sensing mechanism. The improved sensing performance could be attributed to the increasing adsorbed oxygen and tunable band alignment for Pd-ZnO materials. This work provides new insights to the design strategy of Pd-decorated ZnO nanomaterials for high performance gas sensors.

12.
World Neurosurg ; 133: e6-e17, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31284062

RESUMO

BACKGROUND: Pineal region glioma is a rare systematically reported tumor in the literatures, and little is known about its behavior, development, and best treatment strategies because of its complex anatomical relationship and rarity. OBJECTIVE: We reviewed the outcomes of patients with pineal region gliomas in West China hospital in the past 5 years and searched the literature to add more information. As a result, key factors related to prognosis are identified. METHODS: Twenty-five patients with pineal region gliomas were selected and information was collected about detailed medical history, imaging data, treatment methods, pathologic results, and latest neurosurgical radiologic progress during follow-up. RESULTS: Pilocytic astrocytomas (20%) and glioblastomas (24%) were the most common pathologic subtypes. Twenty-three patients underwent open surgery, 3 Gamma Knife radiosurgery, and 4 whole-brain radiation therapy. Chemotherapy was applied to 3 patients. Low-grade gliomas tended to have a better prognosis than did high-grade. Karnofsky Performance Status at admission (≤60) was intimately associated with prognosis for low-grade gliomas. As for high-grade gliomas, patients whose age at admission was ≤30 years had a better prognosis than did older patients (>30 years). However, whatever the grade, there was no overall survival difference as to gender, gross total resection versus not gross total resection, preoperative maximal tumor diameter (≤4 vs. >4 cm), and time since first symptoms (≤30 vs. >30 days), and radiation therapy versus no radiation therapy. CONCLUSIONS: Open surgery is the first-line strategy for pineal region gliomas with tolerable mortality and disability rate. Radiosurgery and chemotherapy can be applied as adjuvant or alternative methods when surgery is contraindicated.


Assuntos
Neoplasias Encefálicas/cirurgia , Glioma/cirurgia , Glândula Pineal/cirurgia , Adolescente , Adulto , Fatores Etários , Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/radioterapia , Quimioterapia Adjuvante , Criança , Pré-Escolar , Terapia Combinada , Irradiação Craniana , Craniotomia/métodos , Feminino , Seguimentos , Glioma/tratamento farmacológico , Glioma/radioterapia , Humanos , Masculino , Pessoa de Meia-Idade , Glândula Pineal/patologia , Prognóstico , Radiocirurgia/métodos , Radioterapia Adjuvante , Estudos Retrospectivos , Análise de Sobrevida , Adulto Jovem
13.
Stereotact Funct Neurosurg ; 97(5-6): 319-336, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31786574

RESUMO

OBJECTIVE: Anterior capsulotomy (AC) is sometimes used as a life-saving treatment for patients with treatment-refractory obsessive-compulsive disorder (Tr-OCD). Most of the previous studies have assessed only total symptoms and have concluded that AC is a safe and effective procedure. Few of these studies have focused on meticulously investigating the variety of results obtained from patients with different subtypes of OCD. This study reviewed the long-term effects of AC on patients with OCD and analyzed the dissimilarity between particular subtypes of the disease in order to determine which groups are more suited to surgical treatment. METHODS: For this retrospective evaluation, we selected 54 consecutive patients from a total of 63 people with Tr-OCD between 2005 and 2014 who had undergone AC by thermocoagulation at our department. Preoperative and follow-up assessments were conducted at multiple time points (before surgery and 1, 3, 6, 12, and 36 months after surgery). The Yale-Brown Obsessive-Compulsive Scale (Y-BOCS), Hamilton Depression Scale (HAMD), and Hamilton Anxiety Scale (HAMA) were used to quantify the symptoms of OCD. According to different elements (clinical manifestation, comorbidity, and whether a patient was more compulsive or more obsessive), we classified patients into various subtypes and analyzed the variation in symptom improvement and adverse effects. RESULTS: The mean Y-BOCS, HAMD, and HAMA scores were, respectively, 27.03, 23.30, and 21.46 preoperatively and 8.50, 7.07, and 7.42, respectively, at 36 months after surgery. Most patients (n = 43, 79.6%) were shown to have been at least partially responsive to surgical treatment at their long-term follow-up. Six patients demonstrated no obvious improvement (Y-BOCS score decreased by <35%), and 5 patients developed recurrences of their conditions. The following subtypes demonstrated better results: contamination/cleaning; obsessions/checking; compulsive behavior dominant; pure OCD; and OCD with Tourette's -syndrome. The subtypes of aggressive/sexual, obsessive thought dominant, compulsive behavior with obsessive thoughts, OCD comorbidity with bipolar disorder, OCD comorbid with severe depression, and OCD comorbid with psychiatric symptoms showed good outcomes. However, surgery was ineffective for patients with the subtypes of symmetry/ordering, hoarding, pure obsessive thoughts, and OCD with obsessive slowness. CONCLUSIONS: AC is effective in reducing symptoms of OCD. By comparing differently classified follow-up results, we found that patients with most subtypes/dimensions of OCD showed good outcomes. How-ever, patients categorized into the OCD subtypes of pure -obsessive thoughts, symmetry/ordering, hoarding, OCD with obsessive slowness, and OCD comorbid with psychiatric symptoms should take into account these results before undergoing AC.


Assuntos
Transtorno Obsessivo-Compulsivo/diagnóstico por imagem , Transtorno Obsessivo-Compulsivo/cirurgia , Psicocirurgia/métodos , Adolescente , Adulto , Cognição/fisiologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Transtorno Obsessivo-Compulsivo/psicologia , Psicocirurgia/tendências , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
14.
Phys Chem Chem Phys ; 21(39): 22039-22047, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31559992

RESUMO

Double-platelet, single-platelet and spherical ZnO microcrystals were fabricated via a facile and controllable hydrothermal method. The morphology of the ZnO microcrystals and the exposure ratio of the (001) crystal surface were regulated by adjusting the pH of the solution. The ZnO microcrystals were modified with Pd nanoparticle loading by simple calcining, and the interaction of Pd nanoparticles (NPs) on the ZnO crystal surface increased its oxygen vacancy content. A micro-amount (0.05 wt%) of Pd NP-doped ZnO double-platelets (D-ZnO-0.05) enhanced the gas sensing of the sensor to 3.5 times that of pure double-platelet ZnO. The gas sensing results indicate that D-ZnO-0.05 exhibits a high response (71.2 for NO2 with 25 ppm), fast response/recovery (25 s/21 s), and superior long-term stability (remained at around 95.5% after 35 days). The enhancement in the gas sensing could be attributed to the catalysis of Pd NPs and the increase in the number of oxygen vacancies as a result of Pd loading. The band structure of D-ZnO-0.05 could be effectively tuned by introducing Pd nanoparticles, as shown in density functional theory (DFT) calculations. The Pd dopant and oxygen vacancies reduce the band gap of the ZnO(001) crystal materials, resulting in excellent sensor performance. It is believed that the D-ZnO-0.05 microcrystals could provide inspiration for crystal growth studies and high NO2 gas sensing.

15.
J Neurosci Methods ; 325: 108349, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31283939

RESUMO

BACKGROUND: Evans blue (EB) is the most widely used tracer to assess BBB leakage. However, a well-established method to obtain visualized and quantitative results of EB extravasation is presently unavailable. NEW METHOD: We reported a novel method to quantify BBB leakage by combining EB and high molecular weight FITC-Dextran (2000 kDa). EB was used for a long circulation duration (60 min) to detect BBB leakage. FITC-Dextran was used for a short circulation duration (10 min) to outline vascular contours. Confocal microscope imaging was used to obtain visualized images of BBB leakage. The result of dividing integrated optical density of EB by vascular areas outlined by FITC-Dextran was treated as the quantification of BBB leakage. RESULTS: This method proved workable in quantifying BBB leakage of specific regions in lipopolysaccharide-induced BBB disruption mice and apoE-/- mice. Sections processed with this method enabled further immunofluorescence staining. Through combining the results of EB extravasation and immunofluorescence staining, the colocalization of specific proteins and BBB disruption was achieved. COMPARISON WITH EXISTING METHODS: Colorimetric and spectrophotometric methods provide us with quantitative results of EB extravasation but fail to locate the specific regions. Fluorescence microscopy imaging can locate specific regions of EB extravasation but a well-established quantitative method is presently unavailable. Our method combines advantages of above two classic methods, providing us with visualized and quantitative information of BBB leakage based on EB extravasation in specific cerebral regions. CONCLUSIONS: The proposed method proved powerful in quantifying BBB leakage of specific regions, which may benefit studies regarding BBB disruption.


Assuntos
Barreira Hematoencefálica/diagnóstico por imagem , Encefalopatias/diagnóstico por imagem , Corantes , Dextranos , Azul Evans , Fluoresceína-5-Isotiocianato/análogos & derivados , Microscopia de Fluorescência/métodos , Animais , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos C57BL
16.
Nanotechnology ; 30(14): 145401, 2019 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-30625420

RESUMO

A Cu2O/TiO2 p-n heterojunction composite was created via a facile, controllable, one-pot hydrothermal method based on cubic Cu2O and TiO2 nanoparticles in the presence of dioctyl sulfosuccinate sodium salt (AOT) surfactant. The TiO2 nanoparticles with an average edge length of ∼10.1 nm were uniformly distributed on the crystal surface of a Cu2O cube {100}. The photocatalytic performance of the composite was effectively tuned by controlling the amount of TiO2. The Cu2O/TiO2 (60 wt%, labeled as CT-60) exhibits the highest enhanced photocatalytic activity in hydrogen production with H2 evolution of 3002.5 µmol g-1. The yield remained around 92.6% after three cycles. Hydrogen production of the CT-60 is 103 and 8.5 fold higher than the cubic Cu2O and TiO2 nanoparticles, respectively. The improvement in photocatalytic performance could be attributed to the formation of p-n heterojunction. Furthermore, the interface effect of Cu2O and TiO2 caused a broader absorbance in the visible-light region and the lower recombination of photogenerated electron-hole pairs. It is believed that the Cu2O/TiO2 p-n heterojunction composites could provide an alternative method to design highly efficient photocatalysts for solar energy.

17.
World Neurosurg ; 123: 371-377, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30583131

RESUMO

OBJECTIVE: This meta-analysis is to evaluate the clinical efficacy of gamma knife radiosurgery (GKRS) for treating cavernous malformations. METHODS: PubMed, Ovid Embase, and Ovid Medline electronic databases were searched. The primary outcome is hemorrhage rate and this meta-analysis is performed. RESULTS: Nine studies are included in this meta-analysis. The overall risk ratio (RR) of hemorrhage rate of pre-GKRS and post-GKRS is 6.08 (95% confidence interval [CI], 5.04-7.35). The overall RR is 3.03 (95% CI, 2.65-4.11) between the hemorrhage rate of pre-GKRS and the first 2 years postradiosurgery, and the overall RR is 12.13 (95% CI, 1.73-85.07) comparing pre-GKRS with 2 years after GKRS. There is no significant difference of the hemorrhage rate between the first 2 years postradiosurgery and 2 years after GKRS (RR = 2.81; 95% CI, 0.20-13.42). The neurologic deficiency is the most common radiosurgery-related complication. CONCLUSIONS: Patients with cerebral cavernous malformations, especially ones that were deep seated and surgically inaccessible, seem to benefit from GKRS owing to a reduction of annual hemorrhage rate in the first 2 years and 2 years after, despite several cases that suffer from negative side effects of radiation.


Assuntos
Hemangioma Cavernoso do Sistema Nervoso Central/cirurgia , Radiocirurgia/métodos , Bases de Dados Bibliográficas/estatística & dados numéricos , Humanos
18.
J Neurosurg ; 128(2): 583-595, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28338440

RESUMO

OBJECTIVE Anterior capsulotomy (AC) is sometimes used as a last resort for treatment-refractory obsessive-compulsive disorder (OCD). Previous studies assessing neuropsychological outcomes in patients with OCD have identified several forms of cognitive dysfunction that are associated with the disease, but few have focused on changes in cognitive function in OCD patients who have undergone surgery. In the present study, the authors investigated the effects of AC on the cognitive function of patients with treatment-refractory OCD. METHODS The authors selected 14 patients with treatment-refractory OCD who had undergone bilateral AC between 2007 and 2013, 14 nonsurgically treated OCD patients, and 14 healthy control subjects for this study. The 3 groups were matched for sex, age, and education. Several neuropsychological tests, including Similarities and Block Design, which are subsets of the Wechsler Abbreviated Scale of Intelligence; Immediate and Delayed Logical Memory and Immediate and Delayed Visual Reproduction, which are subsets of the Wechsler Memory Scale-Revised; and Corrects, Categories, Perseverative Errors, Nonperseverative Errors, and Errors, subtests of the Wisconsin Card Sorting Test, were conducted in all 42 subjects at baseline and after AC, after nonsurgical treatment, or at 6-month intervals, as appropriate. The Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) was used to measure OCD symptoms in all 28 OCD patients. RESULTS The Y-BOCS scores decreased significantly in both OCD groups during the 12-month follow-up period. Surgical patients showed higher levels of improvement in verbal memory, visual memory, visuospatial skills, and executive function than the nonsurgically treated OCD patients. CONCLUSIONS The findings of this study suggest that AC not only reduces OCD symptoms but also attenuates moderate cognitive deficits.


Assuntos
Cognição , Procedimentos Neurocirúrgicos/métodos , Transtorno Obsessivo-Compulsivo/psicologia , Transtorno Obsessivo-Compulsivo/cirurgia , Capsulotomia Posterior/métodos , Adolescente , Adulto , Resistência a Medicamentos , Função Executiva , Feminino , Seguimentos , Humanos , Cápsula Interna/cirurgia , Masculino , Memória de Longo Prazo , Pessoa de Meia-Idade , Testes Neuropsicológicos , Escalas de Graduação Psiquiátrica , Desempenho Psicomotor , Percepção Espacial , Resultado do Tratamento , Escalas de Wechsler , Adulto Jovem
19.
World Neurosurg ; 110: e593-e598, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29175572

RESUMO

BACKGROUND: Microvascular decompression (MVD) and Gamma Knife surgery (GKS) are the primary treatments for trigeminal neuralgia (TN). However, many patients require further surgical treatment after initial surgery for recurrent TN. The aim of this study was to evaluate efficacy and safety of GKS for recurrent TN cases with prior MVD. METHODS: From October 2008 to June 2015, 658 patients at West China Hospital underwent GKS as the only surgical treatment, and 42 patients underwent GKS with prior MVD. The single 4-mm isocenter was located at the cisternal portion of the trigeminal nerve in all patients. Median maximum prescription dose was 85 Gy (range, 70-90 Gy). RESULTS: Median follow-up time was 6.2 years (range, 1.1-10 years). The percentage of patients with or without previous MVD within 1 year was 56.81%, and the percentage of patients who were pain-free was 74.74%. The recurrence rates within 10 years were 49.11% and 43.74% for patients with and without MVD, respectively. Also, 9.52% and 11.04% of patients with and without previous MVD experienced complications as a result of GKS during the long-term follow-up period. Patients who underwent previous MVD showed a significantly lower pain-free rate compared with patients without previous MVD (P = 0.01). There was no statistical significance in the recurrence rate (P = 0.82) or the complications (P = 0.93) in the 2 groups during the long-term follow-up period. CONCLUSIONS: For patients with recurrent TN who previously underwent MVD, GKS remains an efficacious and safe mode of treatment.


Assuntos
Cirurgia de Descompressão Microvascular , Radiocirurgia , Neuralgia do Trigêmeo/radioterapia , Neuralgia do Trigêmeo/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Dor Intratável/diagnóstico por imagem , Dor Intratável/fisiopatologia , Dor Intratável/radioterapia , Dor Intratável/cirurgia , Satisfação do Paciente , Radiocirurgia/efeitos adversos , Recidiva , Retratamento , Resultado do Tratamento , Neuralgia do Trigêmeo/diagnóstico por imagem , Neuralgia do Trigêmeo/fisiopatologia
20.
Nanomaterials (Basel) ; 7(12)2017 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-29168756

RESUMO

Porous Mn2O3 microspheres have been synthesized and in-situ coated with amorphous carbon to form hierarchical C@Mn2O3 microspheres by first producing MnCO3 microspheres in solvothermal reactions, and then annealing at 500 °C. The self-assembly growth of MnCO3 microspheres can generate hollow structures inside each of the particles, which can act as micro-reservoirs to store biomass-glycerol for generating amorphous carbon onto the surfaces of Mn2O3 nanorods consisting of microspheres. The C@Mn2O3 microspheres, prepared at 500 °C, exhibit highly enhanced pseudocapacitive performances when compared to the particles after annealed at 400 °C and 600 °C. Specifically, the C@Mn2O3 microspheres prepared at 500 °C show high specific capacitances of 383.87 F g-1 at current density of 0.5 A g-1, and excellent cycling stability of 90.47% of its initial value after cycling for 5000 times. The asymmetric supercapacitors assembled with C@Mn2O3 microspheres after annealed at 500 °C and activated carbon (AC) show an energy density of up to 77.8 Wh kg-1 at power density of 500.00 W kg-1, and a maximum power density of 20.14 kW kg-1 at energy density of 46.8 Wh kg-1. We can attribute the enhanced electrochemical performances of the materials to their three-dimensional (3D) hierarchical structure in-situ coated with carbon.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA