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1.
Adv Mater ; 36(15): e2307938, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37910130

RESUMO

Layered oxides have become the research focus of cathode materials for sodium-ion batteries (SIBs) due to the low cost, simple synthesis process, and high specific capacity. However, the poor air stability, unstable phase structure under high voltage, and slow anionic redox kinetics hinder their commercial application. In recent years, the concept of manipulating orbital hybridization has been proposed to simultaneously regulate the microelectronic structure and modify the surface chemistry environment intrinsically. In this review, the hybridization modes between atoms in 3d/4d transition metal (TM) orbitals and O 2p orbitals near the region of the Fermi energy level (EF) are summarized based on orbital hybridization theory and first-principles calculations as well as various sophisticated characterizations. Furthermore, the underlying mechanisms are explored from macro-scale to micro-scale, including enhancing air stability, modulating high working voltage, and stabilizing anionic redox chemistry. Meanwhile, the origin, formation conditions, and different types of orbital hybridization, as well as its application in layered oxide cathodes are presented, which provide insights into the design and preparation of cathode materials. Ultimately, the main challenges in the development of orbital hybridization and its potential for the production application are also discussed, pointing out the route for high-performance practical sodium layered oxide cathodes.

2.
Chem Commun (Camb) ; 60(51): 6496-6499, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38836703

RESUMO

Cobalt substitution for manganese sites in Na0.44MnO2 initiates a dynamic structural evolution process, yielding a composite cathode material comprising intergrown P2 and P3 phases. The novel P2/P3 composite cathode exhibits a reversible phase transition process during Na+ extraction/insertion, showcasing its attractive battery performance in sodium-ion batteries.

3.
ACS Appl Mater Interfaces ; 16(2): 2330-2340, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38165730

RESUMO

It remains a tremendous challenge to achieve high-efficiency bifunctional electrocatalysts for both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) for hydrogen production by water splitting. Herein, a novel hybrid of 0D nickel nanoparticles dispersed on the one-dimensional (1D) molybdenum carbide micropillars embedded in the carbon layers (Ni/Mo2C@C) was successfully prepared on nickel foam by a facile pyrolysis strategy. During the synthesis process, the nickel nanoparticles and molybdenum carbide were simultaneously generated under H2 and C2H2 mixed atmospheres and conformally encapsulated in the carbon layers. Benefiting from the distinctive 0D/1D heterostructure and the synergistic effect of the biphasic Mo2C and Ni together with the protective effect of the carbon layer, the reduced activation energy barriers and fast catalytic reaction kinetics can be achieved, resulting in a small overpotential of 96 mV for the HER and 266 mV for the OER at the current density of 10 mA cm-2 together with excellent durability in 1.0 M KOH electrolyte. In addition, using the developed Ni/Mo2C@C as both the cathode and anode, the constructed electrolyzer exhibits a small voltage of 1.55 V for the overall water splitting. The novel designed Ni/Mo2C@C may give inspiration for the development of efficient bifunctional catalysts with low-cost transition metal elements for water splitting.

4.
Zhonghua Nan Ke Xue ; 19(4): 346-9, 2013 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-23678716

RESUMO

OBJECTIVE: To study the effect of Shengjingsan on spermatogenic function following testicular torsion/detorsion in rats and its action mechanism. METHODS: Forty SD male rats were equally randomized to groups A (sham operation), B (control), C (low-dose Shengjingsan), D (medium-dose Shengjingsan) and E (high-dose Shengjingsan). The model of testicular torsion was established by 720 degrees clockwise torsion of the left testis for 4 hours. An hour before operation, the rats of group B received daily gavage of normal saline at 1 ml per kg per d, while those in groups C, D and E that of Shengjingsan at 0.01, 0.02 and 0.03 g per kg per d, all for 35 days. Then all the rats were sacrificed for measuring the semen parameters by CASA and detecting the expression of the CatSper1 gene in the sperm by RT-PCR. RESULTS: Compared with group A, Sperm concentration, the percentage of grade a + b sperm, sperm vitality and CatSper1 expression were significantly lower in group B ([15.30 +/- 6.30] %, [44.42 +/- 6.36] %, [21.00 +/- 6.14] x 10(6)/ml and 1.12 +/- 0.50) than in A ([51.30 +/- 6.60]%, [69.01 +/- 7.20]%, [40.53 +/- 7.01] x 10(6)/ml and 2.04 +/- 0.77) (P < 0.01). Compared with group B, the four parameters were increased remarkably in groups D ([51.63 +/- 3.20] %, [72.09 +/- 2.20]%, [55.30 +/- 5.90] x10(6)/ml and 2.11 +/- 0.20) andE ([55.93 +/- 3.17]%, [73.01 +/- 2.11]%, [58.33 + 4.90] x 10(6)/ml and 2.31 +/- 0.17) (P < 0.01), but not significantly in C ([18.02 +/- 0.23]%, [48.04 +/- 7.01]%, [22.87 +/- 2.10] x 10(6)/ml and 1.19 +/- 0.51) (P > 0.05). CONCLUSION: Shengjingsan can improve sperm parameters following testicular torsion/ detorsion in male rats by regulating their spermatogenic function and improving the expression of CatSper1 in the sperm.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Torção do Cordão Espermático/metabolismo , Espermatogênese/efeitos dos fármacos , Espermatozoides/metabolismo , Animais , Canais de Cálcio/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Contagem de Espermatozoides , Torção do Cordão Espermático/fisiopatologia
5.
CNS Neurosci Ther ; 25(10): 1195-1206, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31556245

RESUMO

AIMS: White matter (WM) injury after intracerebral hemorrhage (ICH) results in poor or even fatal outcomes. As an anti-inflammatory drug, minocycline has been considered a promising choice to treat brain injury after ICH. However, whether minocycline can reduce WM injury after ICH is still controversial. In the present study, we investigate the effect and underlying mechanism of minocycline on WM injury after ICH. METHODS: An ICH model was induced by an injection of autologous blood into the right frontal lobe of piglets. First, transcriptional analysis was performed at day 1 or 3 to investigate the dynamic changes in neuroinflammatory gene expression in WM after ICH. Second, ICH piglets were treated either with minocycline or with vehicle alone. All piglets then underwent magnetic resonance imaging to measure brain swelling. Brain tissue was used for real-time polymerase chain reaction (RT-PCR), immunohistochemistry, Western blot, and electron microscopy. RESULTS: Transcriptional analysis demonstrated that transforming growth factor-ß (TGF-ß)/mitogen-activated protein kinase (MAPK) signaling is associated with microglia/macrophage-mediated inflammation activation after ICH and is then involved in WM injury after ICH in piglets. Minocycline treatment results in less ICH-induced brain swelling, fewer neurological deficits, and less WM injury in comparison with the vehicle alone. In addition, minocycline reduces microglial activation and alleviates demyelination in white matter after ICH. Finally, we found that minocycline attenuates WM injury by increasing the expression of TGF-ß and suppressing MAPK activation after ICH. CONCLUSION: These results indicate that TGF-ß-mediated MAPK signaling contributes to WM injury after ICH, which can be altered by minocycline treatment.


Assuntos
Lesões Encefálicas/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Hemorragia Cerebral/diagnóstico por imagem , Minociclina/uso terapêutico , Substância Branca/diagnóstico por imagem , Animais , Animais Recém-Nascidos , Encéfalo/efeitos dos fármacos , Lesões Encefálicas/tratamento farmacológico , Hemorragia Cerebral/tratamento farmacológico , Masculino , Minociclina/farmacologia , Suínos , Substância Branca/efeitos dos fármacos
6.
J Neurosurg ; 126(2): 527-536, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27058195

RESUMO

OBJECTIVE Chronic frontal hemodynamic disturbances are associated with executive dysfunction in adult patients with moyamoya disease (MMD). However, the impact of surgical revascularization on executive dysfunction and its underlying mechanism remains unclear. The aim of the present study was to examine the postoperative radiological correlates of cognitive improvement and thereby explore its underlying mechanism. METHODS Fourteen patients who met the inclusion criteria were identified at Huashan Hospital, were operated on, and were successfully followed up for 6 months. Postoperative changes in cortical perfusion and regional amplitude of low-frequency fluctuations (ALFF) were examined by SPECT and resting-state functional MRI, respectively. Executive function was evaluated by 2 tests (Trail Making Test Part B and the summation of executive subtests of Memory and Executive Screening [MES-EX]). Follow-up neuropsychological outcomes were then correlated with radiological changes to identify nodes functioning as leading contributors to postoperative executive outcomes. RESULTS All patients underwent successful unilateral bypass procedures, with some operations performed on the left side and some on the right side. At the 6-month follow-up, the baseline and follow-up test scores for the different sides did not differ significantly. The group with good collaterals (Matsushima Grade A, 9 patients) exhibited significantly increased postoperative perfusion (change in [△] hemodynamics) in bilateral frontal (left, p = 0.009; right, p = 0.003) and left parietal lobe (p = 0.014). The Spearman's correlation test suggested that only the right frontal lobe exhibited significant positive postoperative radiological correlates with cognitive performance (△MES-EX vs △hemodynamics, r = 0.620, p = 0.018; △MES-EX vs △ALFF, r = 0.676, p = 0.008; △hemodynamics vs △ALFF, r = 0.547, p = 0.043). Subsequent regional ALFF analysis revealed that the right dorsolateral prefrontal cortex (DLPFC) was the only node in the responsible hemisphere to exhibit significant postoperative changes. CONCLUSIONS The results not only advance our understanding of pathological interactions of postoperative executive performance in adult MMD, but also indicate that the right DLPFC amplitude might be a quantitative predictor of postoperative executive control improvement.


Assuntos
Cognição/fisiologia , Função Executiva/fisiologia , Doença de Moyamoya/fisiopatologia , Doença de Moyamoya/psicologia , Adulto , Revascularização Cerebral , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Doença de Moyamoya/cirurgia , Testes Neuropsicológicos , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios X
7.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 35(1): 57-9, 2004 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-14981816

RESUMO

OBJECTIVE: To probe into the expression and clinical significance of urokinase-type plasminogen activator (uPA) and its receptor (uPAR) in urinary transitional cell carcinoma. METHODS: Expression of uPA and uPAR were detected in 50 cases of renal pelvis and ureter carcinoma and 40 cases of bladder cancer immunohistochemically. RESULTS: The positive rates of uPA and uPAR were closely correlated to the grade and the stage of urinary transitional cell carcinoma (r = 0.979, P < 0.01), whereas uPA and uPAR were not detected in normal kidney, ureter and bladder tissue. CONCLUSION: uPA and uPAR are highly expressed in urinary transitional cell carcinoma and they may be responsible for the tumor invasion and metastasis.


Assuntos
Carcinoma de Células de Transição/metabolismo , Receptores de Superfície Celular/biossíntese , Neoplasias da Bexiga Urinária/metabolismo , Ativador de Plasminogênio Tipo Uroquinase/biossíntese , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais , Carcinoma de Células de Transição/patologia , Feminino , Humanos , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Prognóstico , Receptores de Superfície Celular/genética , Receptores de Ativador de Plasminogênio Tipo Uroquinase , Neoplasias da Bexiga Urinária/patologia , Ativador de Plasminogênio Tipo Uroquinase/genética
8.
Ai Zheng ; 23(6): 704-6, 2004 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-15191676

RESUMO

BACKGROUND & OBJECTIVE: Urokinase-type plasminogen activator (uPA)/its receptor (uPAR), serine protease system, plays a key role in the degradation of extracellular matrix and basement membranes, and intensifying the tumor invasion. The study was designed to investigate the expression of uPA and uPAR in urinary transitional cell carcinoma. The correlation between their expression and tumor invasion was evaluated. METHODS: The expression and localization of uPA and uPAR were examined among 50 cases of renal pelvic and ureter carcinoma and 40 cases of bladder cancer using the PicTure(TM) current type of immunohistochemical two-step method. RESULTS: The normal pelvic, ureter, and bladder did not express uPA and uPAR. The positive expression of uPA and uPAR were concentrated in tumor tissues compared with that in the adjacent tissues. The positive rates of uPA and uPAR expressed the tissues were 33.33% and 50.00% in G1 grade; 88.47% and 96.15% in G3 grade; 37.50% and 50.00% in Ta-T1 tissues; 100.0% and 100.0% in T4 tissues, respectively. The positive rates of uPA and uPAR expression in tumor tissues with higher grade and stage were obviously increased (P< 0.05); meanwhile, there were close correlation between uPA and uPAR (rs=0.979). CONCLUSION: The co-expression of uPA and uPAR was one of the characteristics of urinary transitional cell carcinoma and significantly correlated with tumor stage and grade.


Assuntos
Carcinoma de Células de Transição/metabolismo , Receptores de Superfície Celular/metabolismo , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Neoplasias Urológicas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células de Transição/patologia , Feminino , Humanos , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , Pelve Renal , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Receptores de Ativador de Plasminogênio Tipo Uroquinase , Neoplasias Ureterais/metabolismo , Neoplasias Ureterais/patologia , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/patologia , Neoplasias Urológicas/patologia
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