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1.
Nano Lett ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38634554

RESUMO

Alloying-type anode materials provide high capacity for lithium-ion batteries; however, they suffer pulverization problems resulting from the volume change during cycling. Realizing the cycling reversibility of these anodes is therefore critical for sustaining their electrochemical performance. Here, we investigate the structural reversibility of Sn NPs during cycling at atomic-level resolution utilizing in situ high-resolution TEM. We observed a surprisingly near-perfect structural reversibility after a complete cycle. A three-step phase transition happens during lithiation, accompanied by the generation of a significant number of defects, grain boundaries, and up to 202% volume expansion. In subsequent delithiation, the volume, morphology, and crystallinity of the Sn NPs were restored to their initial state. Theoretical calculations show that compressive stress drives the removal of vacancies generated within the NPs during delithiation, therefore maintaining their intact morphology. This work demonstrates that removing vacancies during cycling can efficiently improve the structural reversibility of high-capacity anode materials.

2.
Medicine (Baltimore) ; 103(10): e37343, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38457578

RESUMO

RATIONALE: Unconsciousness is a nonfocal symptom of transient ischemic attack (TIA) that is frequently observed in patients with vertebrobasilar artery stenosis or occlusion. Conversely, loss of consciousness due to anterior circulation involvement (e.g., middle cerebral artery [MCA]) is a rare occurrence in TIA. PATIENT CONCERNS: This report describes a rare case in a 59-year-old woman who experienced recurrent episodes of altered consciousness because of the occlusion or stenosis of her MCAs. DIAGNOSES: The diagnosis of the case was updated from TIA to acute cerebral infarction, finally. Following initial loss of consciousness, cranial magnetic resonance imaging (MRI) did not reveal any evidence of acute cerebral infarction. However, following the second and third episodes of unconsciousness, the MRI revealed multiple new acute cerebral infarcts affecting both the cerebral hemispheres. Further evaluation through digital subtraction angiography disclosed complete occlusion of the left MCA and severe stenosis of the right MCA. INTERVENTIONS: Early in her illness, the patient was treated with vasodilators, aspirin and atorvastatin. Finally, 2 stents in her right and left MCAs were placed respectively, followed by treatment with aspirin, clopidogrel, and double-dosed atorvastatin calcium. Meanwhile, the patient focused on avoiding conditions which may lead to dehydration in her daily life routine. OUTCOMES: The episodes of unconsciousness of this patient were completely resolved. During the 1-year postoperative follow-up, the patient remained clinically stable without any symptoms of unconsciousness, limb numbness or weakness, or dizziness. LESSONS: These findings suggested that hypoperfusion in the bilateral cerebral hemispheres played a pivotal role in precipitating the patient episodes of unconsciousness. This case underscores the possibility that occlusion or severe stenosis in both MCAs can contribute to recurrent episodes of unconsciousness due to hypoperfusion. Moreover, it emphasizes the association between these episodes of unconsciousness and an increased risk of subsequent ischemic stroke.


Assuntos
Isquemia Encefálica , Ataque Isquêmico Transitório , Acidente Vascular Cerebral , Insuficiência Vertebrobasilar , Humanos , Feminino , Pessoa de Meia-Idade , Ataque Isquêmico Transitório/etiologia , Ataque Isquêmico Transitório/complicações , Constrição Patológica/complicações , Isquemia Encefálica/complicações , Aspirina , Insuficiência Vertebrobasilar/complicações , Doença Aguda , Inconsciência/etiologia , Acidente Vascular Cerebral/complicações , Infarto Cerebral/complicações
3.
Nat Commun ; 14(1): 111, 2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36611034

RESUMO

Two-dimensional (2D) semiconductors are promising in channel length scaling of field-effect transistors (FETs) due to their excellent gate electrostatics. However, scaling of their contact length still remains a significant challenge because of the sharply raised contact resistance and the deteriorated metal conductivity at nanoscale. Here, we construct a 1D semimetal-2D semiconductor contact by employing single-walled carbon nanotube electrodes, which can push the contact length into the sub-2 nm region. Such 1D-2D heterostructures exhibit smaller van der Waals gaps than the 2D-2D ones, while the Schottky barrier height can be effectively tuned via gate potential to achieve Ohmic contact. We propose a longitudinal transmission line model for analyzing the potential and current distribution of devices in short contact limit, and use it to extract the 1D-2D contact resistivity which is as low as 10-6 Ω·cm2 for the ultra-short contacts. We further demonstrate that the semimetal nanotubes with gate-tunable work function could form good contacts to various 2D semiconductors including MoS2, WS2 and WSe2. The study on 1D semimetal contact provides a basis for further miniaturization of nanoelectronics in the future.

4.
Medicine (Baltimore) ; 101(35): e30139, 2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-36107573

RESUMO

BACKGROUND: In the context of the novel coronavirus disease 2019 (COVID-19) pandemic, people have had to stay at home more and make fewer trips to the hospital. Furthermore, hospitals give priority to the treatment of COVID-19 patients. These factors are not conducive to the treatment of diabetic foot, and even increase the risk of amputation. Therefore, how to better treat patients with diabetic foot during the COVID-19 epidemic, prevent further aggravation of the disease and reduce the risk of amputation in patients with diabetic foot has become an urgent problem for doctors around the world. METHODS: The researchers searched PubMed, the Cochrane Library, and the Embase database. The retrieval time was set from the database establishment to October 2021. All studies on treatment of diabetic foot in the COVID-19 pandemic were included in our study. RESULTS: A total of 6 studies were included in this study. In the 6 protocols for treating patients with diabetic foot, the researchers classified patients according to the condition of their diabetic foot. Diabetic foot patients with general conditions received treatment at home, and doctors can guide the wound dressing change and medication treatment of patients through telemedicine. Patients with severe conditions of diabetic foot were admitted to hospital for treatment. Patients were screened for COVID-19 before hospitalization, those infected or suspected of COVID-19 were treated in isolation, and those not infected with COVID-19 were treated in a general ward. CONCLUSION: Through this systematic review, we proposed a new protocol for the treatment of patients with diabetic foot in the context of the COVID-19 pandemic. It provided reference for the treatment of diabetic foot in the context of COVID-19 epidemic. However, the global applicability of the treatment protocol for diabetic foot in the context of COVID-19 epidemic proposed in this study needs further clinical testing.


Assuntos
COVID-19 , Diabetes Mellitus , Pé Diabético , Telemedicina , Amputação Cirúrgica , Diabetes Mellitus/epidemiologia , Pé Diabético/epidemiologia , Pé Diabético/terapia , Humanos , Pandemias
5.
Adv Mater ; 34(30): e2203783, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35657273

RESUMO

Passivation of the Mg anode surface in conventional electrolytes constitutes a critical issue for practical Mg batteries. In this work, a perfluorinated tert-butoxide magnesium salt, Mg(pftb)2 , is codissolved with MgCl2 in tetrahydrofuran (THF) to form an all-magnesium salt electrolyte. Raman spectroscopy and density function theory calculation confirm that [Mg2 Cl3 ·6THF]+ [Mg(pftb)3 ]- is the main electrochemically active species of the electrolyte. The proper lowest unoccupied molecular orbital energy level of the [Mg(pftb)3 ]- anion enables in situ formation of a stable solid electrolyte interphase (SEI) on Mg anodes. A detailed analysis of the SEI reveals that its stability originates from a dual-layered organic/inorganic hybrid structure. Mg//Cu and Mg//Mg cells using the electrolyte achieve a high Coulombic efficiency of 99.7% over 3000 cycles, and low overpotentials over ultralong-cycle lives of 8100, 3000, and 1500 h at current densities of 0.5, 1.0, and 2.0 mA cm-2 , respectively. The robust SEI layer, once formed on a Mg electrode, is also shown highly effective in suppressing side-reactions in a TFSI- -containing electrolyte. A high Coulombic efficiency of 99.5% over 800 cycles is also demonstrated for a Mg//Mo6 S8 full cell, showing great promise of the SEI forming electrolyte in future Mg batteries.

6.
Nanoscale ; 12(29): 15528-15559, 2020 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-32678392

RESUMO

The revival of lithium metal anodes (LMAs) makes it a potent influence on the battery research community in the recent years after the popularity of Li-ion batteries with graphite anodes. The main reason is due to the over ten-fold increase in the capacity of LMAs when compared with that obtained when using graphite, as well as the low redox potential of Li/Li+. However, the full potential of LMAs is heavily inhibited by several factors, such as dendrite growth, pulverization, side reactions, and volume changes. These adversities lower the cell's Coulombic efficiency dramatically if operated without massively excessive Li usage. In this review, we first introduce some of the most significant progresses made in the understandings of the charging/discharging processes at the anode. The importance of combining advanced characterization techniques with classical methods is highlighted. In particular, we aim to explore the hidden links between those studies for obtaining deeper insights. Two main categories of solutions to address common problems, namely, lithium-electrolyte interfacial engineering and three-dimensional hosting of Li, are subsequently illustrated, where each subsection takes a different methodological perspective to demonstrate the relevant state-of-the-art studies. Some interesting approaches to stop dendrites and a brief note on the practical aspects of lithium-metal batteries are provided, too. This review concludes with our essential discoveries from the current literature and valuable suggestions for future LMA research.

7.
Medicine (Baltimore) ; 99(11): e19506, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32176095

RESUMO

RATIONALE: Accessory breast cancer is extremely rare among all cancerous diseases, especially in male patients. There were only few male axillary accessory breast cancer cases that have been reported in scientific literatures so far. Hereby, we would like to discuss a case of male axillary accessory breast cancer found in our hospital. PATIENT CONCERNS: We report a male senile patient suffering from a painful, enlarged, and hardened right axillary mass for more than 20 years. He came for further treatments due to progressive growth of the mass for 11 months with bloody ulceration for more than 1 month. DIAGNOSIS: Pathological examination manifested a grade II infiltrating ductal carcinoma derived from the accessory mammary gland (right axilla), with invasion of local skin. Immunohistochemical examination result: estrogen receptor (++) 90%, progesterone receptor (+++) 100%, human epidermal growth factor receptor-2 (1+), ki67 (20% positive), prostate specific antigen (-), caudal-related homeobox-2 (-), thyroid transcription factor-1 (-), Synaptophysin (+), NapsinA (1), and CK7 (-). INTERVENTIONS: Modified radical mastectomy and axillary lymph nodes clearance were performed on the accessary breast cancer under general anesthesia. Postoperatively, endocrine therapy was provided for the patient, orally-taken Letrozole was recommended for the rest of the patient's life. OUTCOMES: The patient recovered uneventfully and was discharged 3 days after the operation. The patient continued to take Letrozole orally regularly at home and no signs of recurrence were observed. CONCLUSION: Axillary accessory breast cancer in males is extremely rare, with no conspicuous and typical clinical presentations, which leads to inevitable neglect by clinicians. Therefore, there is significant necessity for clinicians to be cautious with this type of disease.


Assuntos
Doença de Alzheimer , Axila , Neoplasias da Mama Masculina/diagnóstico , Carcinoma Ductal de Mama/diagnóstico , Metástase Linfática/diagnóstico , Idoso de 80 Anos ou mais , Neoplasias da Mama Masculina/diagnóstico por imagem , Neoplasias da Mama Masculina/patologia , Neoplasias da Mama Masculina/cirurgia , Carcinoma Ductal de Mama/diagnóstico por imagem , Carcinoma Ductal de Mama/secundário , Carcinoma Ductal de Mama/cirurgia , Diagnóstico Diferencial , Humanos , Metástase Linfática/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Mastectomia Radical Modificada
8.
Drug Deliv ; 26(1): 650-660, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31257946

RESUMO

Purpose: With the increase of population aging and the proportion of overweight and obese, a growing number of people are suffering from diabetes. Insulin (INS) as the most widely used hypoglycemic agent was always chosen as the most effective treatment method of diabetes. In this study, fumaryl diketopiperazine (FDKP) was used as a carrier for the pulmonary delivery of insulin. Patients and methods: The INS-loaded FDKP microspheres (INS@FDKP-MPs) were prepared by spray drying and physicochemical properties (drug loading, particle size, flowability, moisture content, morphology, and crystalline state) were further investigated. Pharmacodynamics was investigated on diabetic model rats administrated by intratracheal insufflation. Results: The INS-loaded FDKP microspheres show satisfied flowability and in vitro deposition with FPF 50.2% and MMAD 3.45 ± 0.13 µm, and the blood glucose level was significantly decreased. Moreover, no inflammatory reaction was observed during the safety study. Conclusion: To sum up, the aim was to develop a non-injection system for insulin, INS@FDKP-MPs powder inhalation with high dose, low toxicity, and good lung deposition inhalation could rapidly decrease the blood glucose level without immune stimulation, which shows remarkably potential on diabetes treatment by pulmonary delivery route.


Assuntos
Dicetopiperazinas/administração & dosagem , Dicetopiperazinas/química , Insulina/administração & dosagem , Insulina/química , Pós/administração & dosagem , Pós/química , Administração por Inalação , Animais , Sistemas de Liberação de Medicamentos/métodos , Inaladores de Pó Seco/métodos , Hipoglicemiantes/química , Masculino , Microesferas , Tamanho da Partícula , Ratos , Ratos Sprague-Dawley
10.
Int J Clin Exp Pathol ; 11(5): 2550-2560, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-31938368

RESUMO

Melanoma treatment with the BRAF V600E inhibitor vemurafenib provides therapeutic benefits, but the common emergence of drug resistance remains a challenge. To define molecular mechanisms of vemurafenib resistance, we generated A375-R, WM35-R cell lines resistant to vemurafenib and found that the p-STAT3 was upregulated in these cells in vitro and in vivo. In particular, activation of the STAT3 pathway was associated with vemurafenib resistance. Inhibition of this pathway with STAT3-specific siRNA (shRNA) sensitized A375-R, WM35-R cells to vemurafenib and induced apoptosis in vitro and in vivo. Moreover, targeting STAT3 induced expression of miR-579-3p and elicited resistance to vemurafenib. However, targeting miR-579-3p with anti- miR-579-3p reversed the resistance to vemurafenib. Together, these results indicate that STAT3-mediated downexpression of miR-579-3p caused resistance to vemurafenib. Our findings suggest novel approaches to overcome resistance to vemurafenib by combining vemurafenib with STAT3 silencing or miR-579-3p overexpression.

11.
Int J Mol Med ; 40(1): 146-154, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28560432

RESUMO

Despite long-term efforts to elucidate the mechanisms responsible for age-related hearing loss (AHL), there is currently no available treatment strategy able to provide a cure. Apoptotic cell death, including that of hair cells and spiral ganglion neurons (SGNs) in the cochlea has been proposed to be the classic theory behind the development of AHL. As calcium signaling plays key roles in signal transduction in apoptosis, in this study, we selected ethosuximide, which is able to block T-type calcium (Ca2+ion) channels, suppressing Ca2+. We hypothesized that the apoptotic pathway may be blocked through the inhibition of T-type Ca2+ channels in cochlear cells in NOD/LtJ mice. NOD/LtJ mice were divided into 2 groups as follows: the ethosuximide-treated and untreated (control) groups. Ethosuximide was administered by intraperitoneal injection every other day from post-natal day seven (P7) until the mice were 8 weeks of age. Following treatment, auditory-evoked brainstem response (ABR) thresholds and distortion product oto-acoustic emission (DPOAE) of the mice in the 2 groups were measured at different time points. Morphometric analysis and the expression of genes involved in the T-type Ca2+-mediated apoptotic pathway were monitored. The ABR and DPOAE results revealed that the NOD/LtJ mice exhibited early-onset and rapidly progressive AHL. A histological examination revealed that hair cell degeneration coincided with the progression of hearing loss. Hair cell and SGN was were significantly lower and auditory function was significantly improved in the ethosuximide-treated group compared to the untreated group. Our data thus indicate that ethosuximide prevents the degeneration of cochlear cells by regulating the expression of genes in apoptotic pathways. Our findings suggest that activating the T-type Ca2+ channel and downstream genes may be key pathological mechanisms responsible for AHL in NOD/LtJ mice.


Assuntos
Envelhecimento/metabolismo , Apoptose/efeitos dos fármacos , Sinalização do Cálcio/efeitos dos fármacos , Cóclea/metabolismo , Etossuximida/farmacologia , Perda Auditiva/prevenção & controle , Envelhecimento/patologia , Animais , Canais de Cálcio Tipo T/metabolismo , Cóclea/patologia , Perda Auditiva/metabolismo , Perda Auditiva/patologia , Camundongos
12.
Biomed Rep ; 4(3): 379-383, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26998280

RESUMO

A migraine is a disabling neurovascular disorder characterized by a unilateral throbbing headache that lasts from 4 to 72 h. The headache is often accompanied by nausea, vomiting, phonophobia and photophobia, and may be worsened by physical exercise. The trigeminovascular system (TVS) is speculated to have an important role in migraines, although the pathophysiology of this disorder remains to be elucidated. Trigeminal ganglion (TG) and spinal trigeminal nucleus caudalis (TNC) are important components of the TVS. Several clinical cases have provided evidence for the involvement of the brainstem in migraine initiation. Electrical stimulation of the trigeminal ganglion (ESTG) in rats can activate TVS during a migraine attack. Calcitonin gene-related peptide (CGRP) is an important vasoactive compound produced following TVS activation. Numerous studies have revealed that adenosine and its receptors have an important role in pain transmission and regulation process. However, only a few studies have examined whether adenosine A2a receptor (A2aR) and adenosine A1 receptor (A1R) are involved in migraine and nociceptive pathways. In the present study, CGRP, A2aR and A1R expression levels were detected in the TG and TNC of ESTG models through reverse transcription-quantitative polymerase chain reaction and western blot analysis. Tianshu capsule (TSC), a type of Chinese medicine, was also used in the ESTG rat models to examine its influence on the three proteins. Results demonstrated that CGRP, A2aR and A1R mediated pain transmission and the regulation process during migraine and the expression of the three proteins was regulated by TSC.

13.
Exp Ther Med ; 9(2): 501-506, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25574223

RESUMO

A meta-analysis was performed to evaluate the efficacy and safety of nerve growth factor (NGF) in the treatment of Bell's palsy. PubMed, the Cochrane Central Register of Controlled Trials, Embase and a number of Chinese databases, including the China National Knowledge Infrastructure, China Biology Medicine disc, VIP Database for Chinese Technical Periodicals and Wan Fang Data, were used to collect randomised controlled trials (RCTs) of NGF for Bell's palsy. The span of the search covered data from the date of database establishment until December 2013. The included trials were screened comprehensively and rigorously. The efficacies of NGF were pooled via meta-analysis performed using Review Manager 5.2 software. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using the fixed-effects model. The meta-analysis of eight RCTs showed favorable effects of NGF on the disease response rate (n=642; OR, 3.87; 95% CI, 2.13-7.03; P<0.01; I2=0%). However, evidence supporting the effectiveness of NGF for the treatment of Bell's palsy is limited. The number and quality of trials are too low to form solid conclusions. Further meticulous RCTs are required to overcome the limitations identified in the present study.

14.
Oncol Lett ; 8(4): 1844-1848, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25202423

RESUMO

The optimal post-operative adjuvant treatment for completely resected gastric cancer with D2 lymphadenectomy remains controversial. The present study was a phase II trial on post-operative chemoradiotherapy in 30 patients with gastric cancer. Patients with stage II to IV (M0) gastric cancer received two cycles of chemotherapy prior to and following chemoradiotherapy. The chemotherapy consisted of a 2-h infusion of oxaliplatin (100 mg/m2) and folinic acid (100 mg/m2), which was followed by a 46-h continuous infusion of 5-fluorouracil (5-FU; 2,400 mg/m2) through a portable pump, repeated every 3 weeks. The chemoradiotherapy consisted of 45 Gy of radiotherapy for 5 weeks and 5-FU continuous infusion (350 mg/m2/day). In total, 30 patients were enrolled in this study. All patients underwent the chemoradiotherapy treatment as planned. A total of 10 (33.3%) patients relapsed; two (6.7%) locoregional relapses and mediastinum metastases, four (13.3%) peritoneal relapses, and four (13.3%) distant metastases. The three-year overall survival and disease-free survival rates were 72.7 and 65%, respectively. The toxicities of chemotherapy and radiotherapy, consisting of neutropenia, nausea and hand-foot syndrome, were observed. In conclusion, post-operative chemoradiotherapy following complete resection of gastric cancer with D2 lymphadenectomy is feasible in a significant subset of patients.

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