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1.
Adv Mater ; 36(1): e2307395, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37740701

RESUMO

Developing bifunctional electrocatalyst for seawater splitting remains a persistent challenge. Herein, an approach is proposed through density functional theory (DFT) preanalysis to manipulate electron redistribution in Ni2 P addressed by cation doping and vacancy engineering. The needle-like Fe-doped Ni2 P with P vacancy (Fe-Ni2 Pv) is successfully synthesized on nickel foam, exhibiting a superior bifunctional hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) catalytic activity for seawater electrolysis in alkaline condition. As a result, bifunctional Fe-Ni2 Pv achieves the industrially required current densities of 1.0 and 3.0 A cm-2 at low voltages of 1.68 and 1.73 V, respectively, for seawater splitting at 60 °C in 6.0 m KOH circumstances. The theoretical calculation and the experimental results collectively reveal the reasons for the enhancement of catalyst activity. Specifically, Fe doping and P vacancies can accelerate the reconstruction of OER active species and optimize the hydrogen adsorption free energy (ΔGH* ) for HER. In addition, the active sites of Fe-Ni2 Pv are identified, where P vacancies greatly improve the electrical conductivity and Ni sites are the dominant OER active centers, meanwhile Fe atoms as active centers for the HER. The study provides a deep insight into the exploration for the enhancement of activity of nickel-based phosphide catalysts and the identification of their real active centers.

2.
Small ; : e2308613, 2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-38072783

RESUMO

Due to the shortage of pure water resources, seawater electrolysis is a promising strategy to produce green hydrogen energy. To avoid chlorine oxidation reactions (ClOR) and the production of more corrosive hypochlorite, enhancing OER electrocatalyst activity is the key to solving the above problem. Considering that transition metal phosphides (TMPs) are promising OER eletrocatalysts for seawater splitting, a method to regulate the electronic structure of FeP by introducing Mn heteroatoms and phosphorus vacancy on it (Mn-FePV ) is developed. As an OER electrocatalyst in seawater solution, the synthesized Mn-FePV achieves extremely low overpotentials (η500  = 376, η1000  = 395 mV). In addition, the Pt/C||Mn-FePV couple only requires the voltage of 1.81 V to drive the current density of 1000 mA cm-2 for overall seawater splitting. The density functional theory (DFT) calculation shows that Mn-FePV (0.21 e- ) has more charge transfer number compared with FeP (0.17 e- ). In-situ Raman analysis shows that phosphorus vacancy and Mn doping can synergistically regulate the electronic structure of FeP to induce rapid phase reconstruction, further improving the OER performance of Mn-FePV . The new phase species of FeOOH is confirmed to can enhance the adsorption kinetics of OER intermediates.

3.
Neurosci Bull ; 39(1): 69-82, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35908004

RESUMO

The optimal protocol for neuromodulation by transcranial direct current stimulation (tDCS) remains unclear. Using the rotarod paradigm, we found that mouse motor learning was enhanced by anodal tDCS (3.2 mA/cm2) during but not before or after the performance of a task. Dual-task experiments showed that motor learning enhancement was specific to the task accompanied by anodal tDCS. Studies using a mouse model of stroke induced by middle cerebral artery occlusion showed that concurrent anodal tDCS restored motor learning capability in a task-specific manner. Transcranial in vivo Ca2+ imaging further showed that anodal tDCS elevated and cathodal tDCS suppressed neuronal activity in the primary motor cortex (M1). Anodal tDCS specifically promoted the activity of task-related M1 neurons during task performance, suggesting that elevated Hebbian synaptic potentiation in task-activated circuits accounts for the motor learning enhancement. Thus, application of tDCS concurrent with the targeted behavioral dysfunction could be an effective approach to treating brain disorders.


Assuntos
Córtex Motor , Estimulação Transcraniana por Corrente Contínua , Estimulação Transcraniana por Corrente Contínua/métodos , Córtex Motor/fisiologia , Neurônios , Estimulação Magnética Transcraniana
4.
J Mol Neurosci ; 71(10): 2095-2106, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33954858

RESUMO

Gut microbiome and plasma metabolome serve a role in the pathogenesis of ischemic stroke (IS). However, the relationship between the microbiota and metabolites remains unclear. This study aimed to reveal the specific asso-ciation between the microbiota and the metabolites in IS using integrated 16S rRNA gene sequencing and liquid chromatography-mass spectrometry (LC-MS) analysis. Male Sprague Dawley (SD) rats were divided into three groups: normal group (n = 8, Normal), model group (n = 9, IS), and sham-operated group (n = 8, Sham). Rats in the IS group were induced by middle cerebral artery occlusion (MCAO), and rats in the Sham group received an initial anesthesia and neck incision only. A neurological function test and 2,3,5-triphenyltetrazolium chloride (TTC) staining were used to assess the IS rat model. Then, the plasma samples were analyzed using untargeted LC-MS. The cecum samples were collected and analyzed using 16S rRNA sequencing. Pearson correlation analysis was performed to explore the association between the gut microbiota and the plasma metabolites. The 16S rRNA sequencing showed that the composition and diversity of the microbiota in the IS and control rats were significantly different. Compared with the Sham group, the abundance of the Firmicutes phylum was decreased, whereas Proteobacteria and Deferribacteres were increased in the IS group. Ruminococcus_sp_15975 and Lachnospiraceae_UCG_001 might be considered as biomarkers for the IS and Sham groups, respectively. LC-MS analysis revealed that many metabolites, such as L-leucine, L-valine, and L-phenylalanine, displayed different patterns between the IS and Sham groups. Pathway analysis indicated that these metabolites were mainly involved in mineral absorption and cholinergic synapse. Furthermore, integrated analysis correlated IS-related microbes with metabolites. For example, Proteobacteria were positively correlated with L-phenylalanine, while they were negatively correlated with eicosapentaenoic acid (EPA). Our results provided evidence of the relationship between the gut microbiome and plasma metabolome in IS, suggesting that these microflora-related metabolites might serve as potential diagnostic and therapeutic markers.


Assuntos
Microbioma Gastrointestinal , Infarto da Artéria Cerebral Média/metabolismo , Metaboloma , Animais , Infarto da Artéria Cerebral Média/sangue , Infarto da Artéria Cerebral Média/microbiologia , Masculino , Proteobactérias/genética , Proteobactérias/isolamento & purificação , Proteobactérias/patogenicidade , RNA Ribossômico 16S/genética , Ratos , Ratos Sprague-Dawley
5.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-353143

RESUMO

<p><b>OBJECTIVE</b>To investigate the curative effect of penile elongation with four differentoperative approaches.</p><p><b>METHODS</b>Through four different operative approaches (the coronary sulcus ringincision, Y or Z shaped incision or Z shaped incision combined with coronary sulcus ring incision), thepenile skin and fascia were degloved until the penile root. Then the superficial and deep dorsal penilesuspensory ligament were cut off. After electric coagulation of the residue ends, the two-side tissue at thefront of the pubic symphysis was sutured. Then the penile skin and fascia were repositioned and the incisionat the inner and outer plate was closed.</p><p><b>RESULTS</b>The increased penile static length was (2.9 ± 0.2) cmwith abdominal wall Y incision (12 cases); (3.1 ± 0.3) cm with transabdominal modified Z incision (260 cases); (3.9 ± 0.7) cm with coronary sulcus ring incision (363 cases); (3.4 ± 0.8) cm with combined incision (39 cases). The lengthening effect was significantly different between the coronary ring incision and abdominal wall Y/Z incision (P < 0.05). The postoperative follow-up period was 6 months to 5.5 years without serious complications. Only 3 cases of subcutaneous hematoma occurred with treatment of debridement and drainage. 4 cases with ischemic necrosis at distal penile skin, were treated with debridement, dressing and physiotherapy, leaving no scar.</p><p><b>CONCLUSIONS</b>Penile lengthening surgery are safe and effective through different approaches. The coronal ring incision has the best therapeutic effect.</p>


Assuntos
Humanos , Masculino , Bandagens , Desbridamento , Drenagem , Eletrocoagulação , Fasciotomia , Seguimentos , Ligamentos , Cirurgia Geral , Necrose , Cirurgia Geral , Tamanho do Órgão , Pênis , Patologia , Cirurgia Geral , Período Pós-Operatório , Procedimentos de Cirurgia Plástica , Métodos , Pele , Fatores de Tempo
6.
Neurosignals ; 18(1): 49-56, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20814222

RESUMO

Hepatocyte growth factor (HGF) and its receptor c-Met play pivotal roles in post-traumatic regeneration of the nervous system. However, following peripheral nerve injury, the role and regulation of the HGF/c-Met system is less clear. Therefore, using a sciatic nerve ligation (SNL) model, spatiotemporal changes in HGF and c-Met expression were detected in the dorsal root ganglions (DRGs) and lumbar spinal cords of adult rats. HGF expression following SNL was found to be significantly decreased in ipsilateral L4-L5 DRGs from day 3 to day 14, with the lowest levels of expression detected on days 5 and 7. In contrast, no significant change in HGF expression was detected in the lumbar spinal cords. c-Met expression in ipsilateral L4-L5 DRGs and within the ipsilateral dorsal horn was found to be significantly up-regulated following SNL, particularly from day 5 to day 14, with peak levels of expression detected on days 7 and 14. In contrast, c-Met levels following SNL consistently remained stable in the spinal ventral horn. These findings suggest that the HGF/c-Met system is spatiotemporally regulated by a unique pattern of signaling pathways induced by peripheral nerve injury, and these pathways have a role in promoting the survival of injured neurons, especially adult DRG sensory neurons.


Assuntos
Gânglios Espinais/metabolismo , Regulação da Expressão Gênica/fisiologia , Fator de Crescimento de Hepatócito/metabolismo , Proteínas Proto-Oncogênicas c-met/metabolismo , Neuropatia Ciática/patologia , Medula Espinal/metabolismo , Animais , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Colina O-Acetiltransferase/metabolismo , Modelos Animais de Doenças , Lateralidade Funcional , Proteína Glial Fibrilar Ácida/metabolismo , Fator de Crescimento de Hepatócito/genética , Masculino , Proteínas Proto-Oncogênicas c-met/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Serotonina/metabolismo , Fatores de Tempo
7.
Zhonghua Shao Shang Za Zhi ; 24(2): 93-6, 2008 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-18785405

RESUMO

OBJECTIVE: To evaluate the antibacterial activity of Ciprofloxacin, Amikacin in combination with beta-lactams against Pseudomonas aeruginosa strains in vitro, to optimize treatment regime for antibiotics on the basis of pharmacokinetics (PK)/pharmacodynamics (PD) and drug sensitivity tests. Methods With checkerboard titration method, the minimal inhibitory concentrations (MIC) of a combination of antibiotics in different concentrations for 33 clinically isolated Pseudomonas aeruginosa strains were determined by broth dilution. Fractional inhibitory concentrations (FIC) were calculated for judging synergic effect of antibiotics. RESULTS: The combination of Amikacin and Ceftazidime showed synergic effects (accounting for 57.6%). The combinations of Ciprofloxacin with Ceftazidime, Cefepime, Imipenem/Cilastatin, Meropenem showed synergic or additive effect. In the study with PK/PD, C(max)/MIC was the principal parameters for evaluation of aminoglycoside and fluoroquinolone antibiotics, while T > MIC was the principal parameter to be used to evaluate beta-lactams antibiotics. CONCLUSION: When antibiotics are used in combination, MICs can be reduced significantly and antibacterial activities are enhanced remarkably. The combination of antibiotics results mainly in synergic or additive effect, and no inhibitory effect is observed. PK/PD analysis plays an important role in planning optimal combination regime to raise clinical efficacy.


Assuntos
Amicacina/farmacologia , Antibacterianos/farmacologia , Ciprofloxacina/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Amicacina/farmacocinética , Antibacterianos/farmacocinética , Unidades de Queimados , Ciprofloxacina/farmacocinética , Quimioterapia Combinada , Humanos , Unidades de Terapia Intensiva , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa/isolamento & purificação , beta-Lactamas/farmacocinética , beta-Lactamas/farmacologia
8.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 32(3): 515-9, 2007 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-17611337

RESUMO

OBJECTIVE: To measure the inferior epigastric artery(IEA),coronary artery and arterial bridge to supply the anatomic and hemodynamic data of IEA in coronary artery bypass grafting for clinicians. METHODS: Anatomic method was adopted to measure the length of IEA, arterial bridge, the outer diameter of IEA and coronary arteries. Colour doppler ultrasound instrument was adopted to measure the caliber and the blood flow rate of IEA and coronary artery. RESULTS: In the anatomic method, the length of IEA was (13.00+/-2.58)cm and the caliber of original IEA was (2.95+/-0.21)mm, the caliber of IEA intersecting with abdomen rectus was (2.51+/-0.32)mm, and (1.60+/-0.26)mm at 1.0 cm below the umbilicus. In color doppler ultrasound method, the caliber of original IEA was (2.98+/-0.37)mm, and at 5 cm from the original spot was (2.60+/-0.27)mm. The blood flow rate was (57.00+/-6.78)cm/s. The main stem caliber of the left coronary artery was (4.90+/-0.76)mm, and that of the right coronary artery was (3.58+/-0.63)mm; the blood flow rate was (48.50+/-7.72)cm/s. The length of the arterial bridge was (10.95+/-1.35) approximately (15.30+/-2.82)cm. CONCLUSION: IEA can bridge the aorta and the coronary artery branches including the left anterior descending branch, the left circumflex branch and the right main coronary artery in free grafting. Its caliber and blood flow rate can match with those of the coronary artery. Before the operation of applying color doppler ultrasound instrument, the safety of IEA in the coronary artery bypass grafting can be evaluated to provide a new safe method in clinical follow-up.


Assuntos
Ponte de Artéria Coronária/métodos , Vasos Coronários/anatomia & histologia , Artérias Epigástricas/anatomia & histologia , Cadáver , Artérias Epigástricas/transplante , Feminino , Humanos , Masculino , Procedimentos Cirúrgicos Vasculares/métodos
9.
Zhonghua Zheng Xing Wai Ke Za Zhi ; 22(4): 294-7, 2006 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-17017147

RESUMO

OBJECTIVE: The study was to evaluate the microscopic changes on skin and soft tissue after repeated expansion for clinical work. METHODS: Six little pigs were divideded as: conventional expansion group, repeated expansion group, and blank control group. Histologic, ultrastructure and bFGF of the skin were observed and measured in each group after samples had been made. RESULTS: The skin and soft tissue after repeated expansion were healthy on the whole. Compared with the conventional expansion group, there was more microscopic change in the repeated expansion group. Collagen fibers were injured evidently. Cells were injured slightly and proliferated much more, and moreover, they were more activated. The content of bFGF was more higher. CONCLUSIONS: The skin and soft tissue after repeated expansion are healthy on the whole by more growth and more repair though repeated expansion may result in more injuries. So repeated expansion is safe and feasible.


Assuntos
Procedimentos Cirúrgicos Dermatológicos , Pele/metabolismo , Expansão de Tecido/métodos , Animais , Feminino , Fator 2 de Crescimento de Fibroblastos/metabolismo , Masculino , Procedimentos de Cirurgia Plástica , Suínos , Porco Miniatura
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