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1.
ACS Appl Mater Interfaces ; 16(19): 24863-24870, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38706443

RESUMO

Water evaporation-induced electricity generators (WEGs) have drawn widespread attention in the field of hydrovoltaic technology, which can convert atmospheric thermal energy into sustainable electric power. However, it is restricted in the wide application of WEGs due to the low power output, complex fabrication process, and high cost. Herein, we present a simple and effective approach to fabricate TiO2-carbon black film-based WEGs (TC-WEGs). A single TC-WEG device can sustainably output an open-circuit voltage of 1.9 V and a maximum power density of 40.9 µW/cm2. Moreover, it has been shown that TC-WEGs exhibit stable electrical energy output when operating in seawater, which can yield a short-circuit current of 1.2 µA. The superior electricity generation performance can be attributed to the intrinsic characteristics of the TC-WEGs, including hydrophilicity, porous structure, and electrical conductivity. This work provides an important reference for the constant harvesting of clean energy.

2.
Nanomicro Lett ; 16(1): 53, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38108934

RESUMO

Interfacial water molecules are the most important participants in the hydrogen evolution reaction (HER). Hence, understanding the behavior and role that interfacial water plays will ultimately reveal the HER mechanism. Unfortunately, investigating interfacial water is extremely challenging owing to the interference caused by bulk water molecules and complexity of the interfacial environment. Here, the behaviors of interfacial water in different cationic electrolytes on Pd surfaces were investigated by the electrochemistry, in situ core-shell nanostructure enhanced Raman spectroscopy and theoretical simulation techniques. Direct spectral evidence reveals a red shift in the frequency and a decrease in the intensity of interfacial water as the potential is shifted in the positively direction. When comparing the different cation electrolyte systems at a given potential, the frequency of the interfacial water peak increases in the specified order: Li+ < Na+ < K+ < Ca2+ < Sr2+. The structure of interfacial water was optimized by adjusting the radius, valence, and concentration of cation to form the two-H down structure. This unique interfacial water structure will improve the charge transfer efficiency between the water and electrode further enhancing the HER performance. Therefore, local cation tuning strategies can be used to improve the HER performance by optimizing the interfacial water structure.

3.
Neurospine ; 20(1): 231-239, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37016869

RESUMO

OBJECTIVE: Long-level intramedullary spinal cord tumors (LIMSCTs) cause complex treatment issues. However, LIMSCTs have rarely been analyzed separately. The authors reported a large case series of LIMSCTs and analyzed the clinical characteristics and treatment outcomes. METHODS: The medical data of patients with LIMSCTs at our institution between January 2015 and December 2019 were retrospectively reviewed. Demographics, tumor size and location, pathology, extent of resection, and neurological functional status were collected. RESULTS: A total of 43 consecutive cases were included. Twenty-three cases (53.5%) of LIMSCTs were ependymal tumors. All patients with ependymal tumors achieved gross total resection (GTR). In ependymal tumor cases, 3 cases (13%) of ependymal tumors experienced postoperative neurological deterioration, and 66% of them showed an improvement at follow-up; 25.6% were low-grade astrocytic tumors. The rates of GTR, subtotal resection (STR) and partial resection (PR) were 63.6%, 27.3%, and 9.1%, respectively. Twenty-seven percent cases showed postoperative neurological worsening, and 33% of them had an improvement at follow-up; 20.9% were high-grade astrocytic tumors. The excision rates were 44.4% for GTR, 44.4% for STR, and 11% for PR, respectively. Fifty-five percent cases showed postoperative neurological worsening, and none of them had an improvement at follow-up. CONCLUSION: In this series, all LIMSCTs were gliomas. Aggressive tumor resection did not increase the risk of long-term functional deterioration in ependymal tumors and low-grade astrocytic tumors, but in high-grade astrocytic tumors, patients had a higher risk of neurological deterioration and difficulty in recovery. In ependymal tumors and low-grade astrocytic tumors, patients can achieve long-time survival after performing aggressive tumor resection.

4.
Front Neurol ; 14: 1069861, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36891476

RESUMO

Objective: The characteristic morphological parameters (bony posterior fossa volume (bony-PFV), posterior fossa crowdness, cerebellar tonsillar hernia, and syringomyelia) and CSF dynamics parameters at the craniocervical junction (CVJ) in Chiari malformation type I (CMI) were measured. The potential association between these characteristic morphologies and CSF dynamics at CVJ was analyzed. Methods: A total of 46 cases of control subjects and 48 patients with CMI underwent computed tomography and phase-contrast magnetic resonance imaging. Seven morphovolumetric measures and four CSF dynamics at CVJ measures were performed. The CMI cohort was further divided into "syringomyelia" and "non-syringomyelia" subgroups. All the measured parameters were analyzed by the Pearson correlation. Results: Compared with the control, the posterior cranial fossa (PCF) area, bony-PFV, and CSF net flow were significantly smaller (P < 0.001) in the CMI group. Otherwise, the PCF crowdedness index (PCF CI, P < 0.001) and the peak velocity of CSF (P < 0.05) were significantly larger in the CMI cohort. The mean velocity (MV) was faster in patients with CMI with syringomyelia (P < 0.05). In the correlation analysis, the degree of cerebellar tonsillar hernia was correlated with PCF CI (R = 0.319, P < 0.05), MV (R = -0.303, P < 0.05), and the net flow of CSF (R = -0.300, P < 0.05). The Vaquero index was well correlated with the bony-PFV (R= -0.384, P < 0.05), MV (R = 0.326, P < 0.05), and the net flow of CSF (R = 0.505, P < 0.05). Conclusion: The bony-PFV in patients with CMI was smaller, and the MV was faster in CMI with syringomyelia. Cerebellar subtonsillar hernia and syringomyelia are independent indicators for evaluating CMI. Subcerebellar tonsillar hernia was associated with PCF crowdedness, MV, and the net flow of CSF at CVJ, while syringomyelia was associated with bony-PFV, MV, and the net flow of CSF at the CVJ. Thus, the bony-PFV, PCF crowdedness, and the degree of CSF patency should also be one of the indicators of CMI evaluation.

5.
Neurospine ; 20(4): 1480-1489, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38171314

RESUMO

OBJECTIVE: To evaluate the impact of H3K27M mutation in the prognosis of histological high-grade intramedullary astrocytoma. METHODS: A total of 78 patients who were diagnosed with high-grade spinal cord astrocytoma were included. Clinical data consisting demographic, radiological, molecular features and treatment data were recorded. Univariate and multivariate Cox analysis were performed to investigate variables associated with survival outcome of histological high-grade spinal cord astrocytoma. RESULTS: Median survival time was 21 months. Overall survival (OS) at 1 and 3 years was 65.7% and 40.7%, respectively. Sex, location, and tumor span did not present significant association with OS. Patients with H3K27M mutation showed significant shorter duration of symptom than patients with H3K27 wild-type. As respect to adjuvant treatment, adjuvant radiotherapy and chemotherapy were associated with favorable OS (both p = 0.01). Younger patients (age ≤ 18 years) had shorter OS (p = 0.008) than adult patients (age > 18 years). Of note, H3K27M mutation did not show significant impact on the survival outcome, regardless of histology grade 3 or grade 4 (p = 0.3). CONCLUSION: Histological high-grade spinal cord astrocytoma has dismal prognosis. Our study demonstrated that H3K27M mutation did not show significant impact on survival outcome of histological high-grade spinal cord astrocytoma.

6.
J Int Med Res ; 50(1): 3000605221075814, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35099308

RESUMO

Acute subarachnoid hemorrhage (SAH) presentation is a very rare occurrence in spinal schwannomas. We report a case of lumbar schwannoma in a patient presenting first with acute SAH. A 40-year-old man was referred to our department 7 days after the sudden onset of headache, neck pain, and fever. SAH was suspected; however, head computed tomography (CT) findings were normal. A lumbar puncture indicated blood-stained cerebrospinal fluid (CSF). Moreover, the CSF pressure changed from 200 mmH2O to 90 mmH2O after drainage of 10 mL of CSF indicating a blockage of CSF. Subsequent magnetic resonance imaging (MRI) confirmed an intradural tumor with SAH, which also caused blockage of the CSF circulation. The patient underwent immediate surgery and fully recovered. In conclusion, the early diagnosis and total removal of the tumor and blood clot significantly improved the patient's outcome. There is a high index of suspicion for spinal tumors resulting in SAH when there is a CSF pressure change after lumbar puncture in an SAH patient.


Assuntos
Neurilemoma , Neoplasias da Medula Espinal , Hemorragia Subaracnóidea , Adulto , Humanos , Imageamento por Ressonância Magnética , Masculino , Neurilemoma/complicações , Neurilemoma/diagnóstico por imagem , Neurilemoma/cirurgia , Neoplasias da Medula Espinal/complicações , Neoplasias da Medula Espinal/diagnóstico por imagem , Neoplasias da Medula Espinal/cirurgia , Punção Espinal , Hemorragia Subaracnóidea/diagnóstico por imagem , Hemorragia Subaracnóidea/cirurgia
7.
Int J Surg Case Rep ; 81: 105747, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33743243

RESUMO

INTRODUCTION AND IMPORTANCE: Huge intramedullary tumor is a rare condition. Surgical management of such huge ependymoma is technically challenging. We reported one case of 300 mm long intramedullary spinal cord ependymoma from oblongata to T4, which was satisfactorily en bloc gross total resected and the cervical spine alignment was successfully maintained by laminoplasty. CASE PRESENTATION: A 30-year-old man presented to our service with two-year progressive neck pain combined with bilateral sense disorders of both the upper and lower extremities. The neurological grade was ASIA D. Repeat MRI imaging demonstrated a "medulla oblongata to T4" intramedullary spinal cord tumor complicated with cervical physiological curvature loss. CLINICAL DISCUSSION: Laminectomies were made at the C1-T4 level by a milling cutter. The tumor was gently separated bilaterally. The ventral part of the tumor was separated from the cranial and the caudal ends until reaching the middle site of the tumor. The whole tumor was isolated en bloc. Titanium miniplates were used bilaterally to fix both sides of the laminoplasty section on each level. At the 2-year postoperative follow-up, the muscle strength of both the upper and lower limbs were grade Ⅳ. No tumor recurrence was detected. CONCLUSION: The total removal of an intramedullary ependymoma should be recommended as soon as the diagnosis is made, regardless of its extension. Long-level laminoplasty could be an effective alternative option to maintain the proper spine alignment.

8.
Int J Surg Case Rep ; 79: 234-238, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33485173

RESUMO

INTRODUCTION AND IMPORTANCE: Long-level intramedullary astrocytomas complicated with spine scoliosis are rare. Surgical treatment of such tumors becomes more complicated and challenging when spinal scoliosis is present. However, studies describing the treatment of long segmental intramedullary spinal cord astrocytomas complicated with severe spine scoliosis have been rarely reported. CASE PRESENTATION: Two cases of long-level intramedullary astrocytomas complicated with severe spine scoliosis were surgically treated with one-stage operation of tumor resection and scoliosis correction in this report. Case 1: A 16-year-old boy presented to our hospital with a five-month progressive paresthesia, weakness of the left lower limb, and a long-time abnormal body appearance. MRI showed a T4-T12 intramedullary tumor combined with spinal scoliosis. Case 2: A 14-year-old boy presented at our service with a 6-year history of visible spine scoliosis and a 1-year progressive motor disability of bilateral lower limbs. Spine MRI indicated a long-level abnormal syringomyelia signal from C4 to L1 and there was irregular enhancement after intravenous contrast medium administration at C7-T2 and T9-T12 level. DISCUSSION: We performed a laminectomy over the whole length of the tumor and corrected the scoliosis with trans-pedicle screws. The patients exhibited a long-time tumor free with largely neurological function preservation. One-stage operation did not generate severe short- or long-term complications. The correction of the scoliosis prevented the progression of the spinal deformity and facilitated the recovery of normal life. CONCLUSION: This case report demonstrates that the one-stage resection of long-level intramedullary astrocytoma and correction of the complicated scoliosis might be a feasible option.

9.
J Neurosurg Case Lessons ; 1(17): CASE2190, 2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35855221

RESUMO

BACKGROUND: The anterior cervical corpectomy and fusion approach has been reported for the removal of ventral cervical tumors. However, the normal cervical vertebral body and the adjacent intervertebral discs have to be sacrificed. In this paper, the authors describe a novel anterior cervical transvertebral approach for the resection of cervical intraspinal ventral lesions. OBSERVATIONS: A patient presented with an anteriorly placed extramedullary cyst. An anterior cervical transvertebral open-window and close-window approach was designed and applied to resect an intraspinal ventral enterogenous cyst. With this novel technique, a square was cut through the whole vertebral body at the four sides. After the cyst resection, the bone block was restored and fixed with a titanium miniplate. The lesion was totally resected, and the compression of the spinal cord was relieved. The physiological function of the cervical spine was kept intact after the operation. There was no postsurgical complication. The cervical alignment was normal at the 1-year postoperative follow-up. LESSONS: The anterior cervical transvertebral open-window and close-window approach was developed and confirmed to be effective for the resection of cervical intraspinal lesions. The cervical physiological structure and function can be restored with this new technique.

10.
Neurosci Lett ; 720: 134747, 2020 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-31927057

RESUMO

Spinal cord injury (SCI) induced by trauma is a devasting neurological consequences. Liraglutide, a glucagon-like peptide-1 (GLP-1) analog, has be shown to have neuroprotective effects in several neurodegenerative diseases. However, the potential benefits of liraglutide as well as the underlying mechanisms for its therapeutic benefit for SCI are unclear. We aimed to investigate the therapeutic benefits and decipher the potential signaling pathways of liraglutide in spinal contusion injury. A SD rat model with controlled spinal contusion was established for this study. Behavioral tests and histological examinations were performed to assess the neuroprotective benefits. Several autophagy markers were measured by western blot analysis and immunofluorescence staining, including LC3B, Beclin-1 and p62. In addition, the AMPK-FOXO3 signaling pathway was investigated. Our results demonstrated that liraglutide treatment strongly enhanced motor function recovery and alleviated the degree of necrosis and loss of motor neurons in the spinal cord tissue after contusion. Autophagic responses were activated by liraglutide. LC3B-II/LC3B-I and Beclin-1 expression was enhanced while p62 expression was reduced. In addition, the levels of p-AMPK/AMPK, FOXO3 and p-FOXO3 (phospho S253) were notably up-regulated by liraglutide. These effects were partly reversed by Compound C, an AMPK inhibitor. In summary, our results demonstrated that liraglutide was therapeutically beneficial in treating spinal contusion injury and its underlying mechanism was through the activation of autophagic responses through the AMPK-FOXO3 signaling pathway.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Autofagia/efeitos dos fármacos , Proteína Forkhead Box O3/metabolismo , Liraglutida/administração & dosagem , Fármacos Neuroprotetores/administração & dosagem , Traumatismos da Medula Espinal/metabolismo , Animais , Modelos Animais de Doenças , Feminino , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
11.
Peptides ; 101: 89-94, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29329976

RESUMO

GLP-1 signaling pathway has been well studied for its role in regulating glucose homeostasis, as well as its beneficial effects in energy and nutrient metabolism. A number of drugs based on GLP-1 have been used to treat type 2 diabetes mellitus. GLP-1R is expressed in multiple organs and numerous experimental studies have demonstrated that GLP-1 signaling pathway exhibits pro-survival functions in various disorders. In the central nervous system, stimulation of GLP-1R produces neuroprotective effects in specific neurodegenerative disorders, such as Alzheimer's disease and Parkinson's disease. The preproglucagon neurons located in the brainstem can also produce GLP-1. GLP-1 analogs have a long-acting effect and are able to pass the blood-brain barrier, which probably extends the therapeutic efficacy of GLP-1R activation. Neurodegenerative or traumatic conditions can damage the spinal cord and result in motor and sensory dysfunction. Evidence supports that GLP-1R activation in the spinal cord possesses beneficial effects and significant therapeutic potential. Herein, we review studies that have focused on GLP-1 and the spinal cord, and summarize the expression of GLP-1R and the innervation of PPG neurons in the spinal cord, as well as the potential therapeutic benefits of GLP-1R activation.


Assuntos
Peptídeo 1 Semelhante ao Glucagon/uso terapêutico , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Fármacos Neuroprotetores/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Traumatismos da Medula Espinal/tratamento farmacológico , Medula Espinal/metabolismo , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Animais , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Humanos , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Medula Espinal/patologia , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/patologia
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