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1.
Orthop Surg ; 13(7): 2163-2169, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34516043

RESUMO

OBJECTIVE: To investigate the curative effect of closed reduction and external fixation in the treatment of grade IV supination-external rotation fractures of the ankle joint. METHODS: Fifty-six patients treated with closed reduction and external fixation from February 2016 to March 2020 were included in this retrospective study, all with sprains. After receiving nerve block anesthesia, the patient underwent closed reduction under C-arm fluoroscopy, and the ankle joint was fixed in a dorsiflexion-inversion position with casting and splints after the end of the fracture met the reduction standard by fluoroscopy. One week and four weeks after the reduction treatment, oblique axial and coronal MR scans of the ankle joint were performed to determine the degree of injury and healing of the inferior tibiofibular syndesmosis; anteroposterior and lateral X-rays of the ankle joint (including the ankle acupoints) were regularly reviewed to observe the fracture alignment and healing. Combined with the images and physical examination, the patients were instructed to undergo ankle weight-bearing rehabilitation training when they met the clinical healing standard, and at the last follow-up, the Mazur ankle evaluation and grading system were used for evaluation. After the reduction, the images were evaluated according to the Leeds standard. The image healing of fracture was evaluated by callus growth criteria. RESULTS: The follow-up period of patients ranged from 11 to 58 months, with an average of 26.8 months. The clinical healing time was (8.51 ± 2.12) weeks. The excellent and good rating after reduction was 82.1%, and the excellent and good rating during clinical fracture healing was 73.2%, according to the Leeds imaging evaluation. According to the Mazur ankle evaluation and grading system, the excellent and good rating was 75.0%. Pairwise comparison of callus images at 4, 6 and 12 weeks showed statistically significant differences (P < 0.05), suggesting callus growth at different time periods. A total of 56 patients had anterior inferior tibial fibular ligament (AITFL) injuries (grade II-III), among which 11 patients had AITFL injuries combined with grade II injuries of the interosseous ligament (IOL) and 4 patients had AITFL injuries combined with grade III injuries of the IOL. CONCLUSIONS: Most of the patients with grade IV supination-external rotation fracture of the ankle joint had good prognosis after closed reduction and plaster combined with splint fixation. For patients with IOL injury who had poor prognosis, open reduction and internal fixation therapy is appropriate.

2.
Zhen Ci Yan Jiu ; 46(7): 610-5, 2021 Jul 25.
Artigo em Chinês | MEDLINE | ID: mdl-34369683

RESUMO

OBJECTIVE: To observe the effect of tiaoren tongdu acupuncture method (for regulating the function of the Conception Vessel and promoting the circulation of the Governor Vessel) on fractional anisotropy (FA) and upper-extremity motor function after cerebral infarction by diffusion densor imaging (DTI) technology. METHODS: The patients with cerebral infarction were divided into an acupuncture group and a control group according to the random number table method, 27 cases in each group. In the control group, the basic treatment with conventional medication was used. In the acupuncture group, on the basic treatment as the control group, the tiaoren tongdu acupuncture method was provided. Main acupoints included Baihui (GV20), Shuigou(GV26), Chengjiang(CV24), Guanyuan(CV4), Qihai (CV6), Zhongwan (CV12), Shenting(GV24) and Mingmen(GV4). Supplementary points included Jianyu(LI15), Chize(LU5), Houxi (SI3), Weizhong (BL40), Zusanli (ST36) and Taichong (LR3) on the affected side. The needles were retained for 30 min. Acupuncture was given once a day, at the interval of 1 days every week, consecutively for 4 weeks. The upper extremity Fugl-Meyer assessment (UE-FMA) was used to evaluate the motor function of upper extremity before and after treatment. DTI was adopted to observe the FA values of infarct focus, posterior limb of internal capsule (PLIC) and cerebral peduncle on the affected side, as well as FA values at the corresponding parts on the healthy side in the patients of two groups. The relative differences (rFA) were calculated. RESULTS: Compared with their own pretreatment, the UE-FMA value was significantly higher after treatment in either of two groups separately (P<0.05 in the control group, P<0.01 in the acupuncture group). The difference of UE-FMA before and after treatment in the acupuncture group was larger than that in the control group (P<0.05). The FA and rFA values in infarct focus were higher than those before treatment in the two groups (P<0.05). The FA and rFA differences before and after treatment in the infarct focus and PLIC on the affected side were higher in the acupuncture group as compared with the control group (P<0.05). The UE-FMA difference was positively correlated with the rFA difference of each part in either group (P<0.05), and the correlation was the strongest in PLIC on the affected side in either group (P<0.01). CONCLUSION: Tiaoren tongdu acupuncture significantly improves the upper limb movement function after cerebral infarction. The rFA value of PLIC combined with UE-FMA can be used to evaluate the therapeutic effect of acupuncture on the upper extremity movement after cerebral infarction.


Assuntos
Terapia por Acupuntura , Acidente Vascular Cerebral , Pontos de Acupuntura , Anisotropia , Infarto Cerebral/diagnóstico por imagem , Infarto Cerebral/terapia , Humanos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/terapia , Resultado do Tratamento , Extremidade Superior
3.
Cancer Cell Int ; 21(1): 442, 2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-34419067

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) remains one of the most common malignant neoplasms. Lysophosphatidylcholine acyltransferase 1 (LPCAT1) plays a key role in the lipid remodelling and is correlated with various neoplasms. Nonetheless, the biological functions and molecular mechanisms of LPCAT1 underlying HCC remain obscure. METHODS: In the present study, we investigated the role of LPCAT1 in the progression of HCC. In-house RT-qPCR, tissue microarrays, and immunohistochemistry were performed to detect the expression levels and the clinical value of LPCAT1 in HCC. External datasets were downloaded to confirm the results. Proliferation, migration, invasiveness, cell cycle, and apoptosis assays were conducted to reveal the biological effects LPCAT1 has on SMMC-7721 and Huh7 cells. HCC differentially expressed genes and LPCAT1 co-expressed genes were identified to explore the molecular mechanisms underlying HCC progression. RESULTS: LPCAT1 showed upregulated expression in 3715 HCC specimens as opposed to 3105 non-tumour specimens. Additionally, LPCAT1 might be an independent prognostic factor for HCC. LPCAT1-knockout hampered cellular proliferation, migration, and metastasis in SMMC-7721 and Huh7 cells. More importantly, the cell cycle and chemical carcinogenesis were the two most enriched signalling pathways. CONCLUSIONS: The present study demonstrated that increased LPCAT1 correlated with poor prognosis in HCC patients and fuelled HCC progression by promoting cellular growth, migration, and metastasis.

4.
Bioengineered ; 12(1): 1627-1641, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33949293

RESUMO

Hepatocellular carcinoma (HCC) is a leading cause of mortality in cancer patients, but the association between miR-125b-2-3p and the onset and prognosis of HCC has not been reported in previous studies; thus, the clinicopathological implications of miR-125b-2-3p in HCC require elaboration. To examine the expression of miR-125b-2-3p in HCC, both in-house RT-qPCR and public datasets were used to calculate the standard mean difference (SMD) and the summary receiver operating characteristic (sROC). MiR-125b-2-3p was markedly lower in HCC than in non-tumor tissue as assessed by the in-house RT-qPCR which was confirmed by the integrative analysis showing the SMD being -0.69 and the area under the curve (AUC) being 0.84 based on 1,233 cases of HCC and 630 cases of non-HCC controls. To gain a overview of the clinical value of miR-125b-2-3p in HCC, all possible datasets were integrated, and lower miR-125b-2-3p levels could lead to poorer differentiation and a more advanced clinical stage of HCC. The hazard ratio (HR) of miR-125b-2-3p was also calculated using a Cox proportional hazards model, and the miR-125b-2-3p level could act as an protective indication for the survival with the HR being 0.74 based on 586 cases of HCC. Furthermore, the effect of nitidine chloride (NC), a natural bioactive phytochemical alkaloid, on the regulation of miR-125b-2-3p and its potential targets was also investigated. The miR-125b-2-3p level was increased after NC treatment, while the expression of its potential target PRKCA was reduced. Above all, a low-expressed level of miR-125b-2-3p plays a tumor suppressive role in HCC.


Assuntos
Carcinoma Hepatocelular/genética , Regulação para Baixo/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/genética , MicroRNAs/genética , Carcinoma Hepatocelular/patologia , Feminino , Perfilação da Expressão Gênica , Humanos , Neoplasias Hepáticas/patologia , Masculino , MicroRNAs/metabolismo , Prognóstico , Curva ROC , Fatores de Risco
5.
Psychol Health Med ; : 1-6, 2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-33971765

RESUMO

This study aimed to explore which age group out of the patients in quarantine wards with novel coronavirus pneumonia is the most susceptible to anxiety. The data of 32 Covid-19 patients isolated in the quarantine wards of the second Infectious Diseases Department of Baoding Hospital and 71 Covid-19 patients in Tangshan City Infectious Disease Hospital from January 24th to March 5th, 2020, a total of 103 patients, were analyzed. Among these patients, 97 isolated patients were scored with a self-rating anxiety scale (SAS) score seven days after quarantine, and the correlation between age and score was analyzed. These 97 isolated patients were then divided into three groups according to age: group A (up to 35 years old), group B (36-60 years), and group C (over 60 years). One-way analysis of variance was used to compare the scores among groups. The Q-test was used for pairwise comparison.P < 0.05 was considered statistically significant.There was a negative correlation between age and SAS score in isolated Covid-19 patients, and the differences in the score among groups were statistically significant. Patients under 35 years old were more prone to anxiety when they were isolated for seven days. Isolated patients aged up to 35 years old need more attention from quarantine medical staff, communication should be strengthened, and psychological intervention from psychotherapists should be given if necessary.

6.
Adv Mater ; 33(23): e2100407, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33909930

RESUMO

Although oxygen vacancies (Ov s) play a critical role for many applications of metal oxides, a controllable synthetic strategy for anisotropic Ov s remains a great challenge. Here, a novel strategy is proposed to achieve the regional dual structure with anisotropic Ov s at both the surface and in the interior of TiO2 by constructing amorphous domains. The as-prepared black TiO2 with amorphous domains exhibits superior activity in degrading rhodamine B (RhB) solutions, which can instantly decompose RhB with just a shake. First-principle simulations reveal that subsurface Ov s in TiO2 are energetically favored, resulting in the formation of amorphous domains in the interior region via diffusion of surface-formed Ov s into the subsurface. The stable Ov -induced amorphous domains in TiO2 with enhanced catalytic performances provide a scalable strategy to practical Ov engineering in functional metal oxides.

7.
Small ; 17(16): e2004453, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33538108

RESUMO

Single atomic Pt catalysts exhibit particularly high hydrogen evolution reaction (HER) activity compared to conventional nanomaterial-based catalysts. However, the enhanced mechanisms between Pt and their coordination environment are not understood in detail. Hence, a systematic study examining the different types of N in the support is essential to clearly demonstrate the relationship between Pt single atoms and N-doped support. Herein, three types of carbon nanotubes with varying types of N (pyridine-like N, pyrrole-like N, and quaternary N) are used as carbon support for Pt single atom atomic layer deposition. The detailed coordination environment of the Pt single atom catalyst is carefully studied by electron microscope and X-ray absorption spectra (XAS). Interestingly, with the increase of pyrrole-like N in the CNT support, the HER activity of the Pt catalyst also improves. First principle calculations results indicate that the interaction between the dyz and s orbitals of H and sp3 hybrid orbital of N should be the origin of the superior HER performance of these Pt single atom catalysts (SACs).

8.
Respiration ; 100(2): 116-126, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33486496

RESUMO

BACKGROUND: There is still no clinical evidence available to support or to oppose corticosteroid treatment for coronavirus disease 2019 (COVID-19) pneumonia. OBJECTIVE: To investigate the efficacy and safety of corticosteroid given to the hospitalized patients with COVID-19 pneumonia. METHODS: This was a prospective, multicenter, single-blind, randomized control trial. Adult patients with COVID-19 pneumonia who were admitted to the general ward were randomly assigned to either receive methylprednisolone or not for 7 days. The primary end point was the incidence of clinical deterioration 14 days after randomization. RESULTS: We terminated this trial early because the number of patients with COVID-19 pneumonia in all the centers decreased in late March. Finally, a total of 86 COVID-19 patients underwent randomization. There was no difference of the incidence of clinical deterioration between the methylprednisolone group and control group (4.8 vs. 4.8%, p = 1.000). The duration of throat viral RNA detectability in the methylprednisolone group was 11 days (interquartile range, 6-16 days), which was significantly longer than that in the control group (8 days [2-12 days], p = 0.030). There were no significant differences between the 2 groups in other secondary outcomes. Mass cytometry discovered CD3+ T cells, CD8+ T cells, and NK cells in the methylprednisolone group which were significantly lower than those in the control group after randomization (p < 0.05). CONCLUSIONS: From this prematurely closed trial, we found that the short-term early use of corticosteroid could suppress the immune cells, which may prolong severe acute respiratory syndrome coronavirus 2 shedding in patients with COVID-19 pneumonia. TRIAL REGISTRATION: ClinicalTrials.gov, NCT04273321.


Assuntos
COVID-19/tratamento farmacológico , Glucocorticoides/uso terapêutico , Hospitalização , Metilprednisolona/uso terapêutico , Faringe/química , RNA Viral/isolamento & purificação , Eliminação de Partículas Virais , Adulto , Idoso , Antibacterianos/uso terapêutico , Antivirais/uso terapêutico , Complexo CD3 , Linfócitos T CD8-Positivos , COVID-19/sangue , COVID-19/terapia , COVID-19/transmissão , Teste de Ácido Nucleico para COVID-19 , Progressão da Doença , Intervenção Médica Precoce , Oxigenação por Membrana Extracorpórea , Feminino , Humanos , Células Matadoras Naturais , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Oxigenoterapia , Quartos de Pacientes , Faringe/virologia , Modelos de Riscos Proporcionais , Respiração Artificial , SARS-CoV-2 , Método Simples-Cego , Subpopulações de Linfócitos T , Linfócitos T , Fatores de Tempo , Resultado do Tratamento
9.
BMC Musculoskelet Disord ; 22(1): 54, 2021 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-33422037

RESUMO

BACKGROUND: PIA has been proven to be a predictor for postoperative dysphagia in patients who undergo occipitospinal fusion. However, its predictive effect for postoperative dysphagia in patients who undergo OCF is unknown. The aim of this study was to evaluate the predictive ability of the pharyngeal inlet angle (PIA) for the occurrence of postoperative dysphagia in patients who undergo occipitocervical fusion (OCF). METHODS: Between 2010 and 2018, 98 patients who had undergone OCF were enrolled and reviewed. Patients were divided into two groups according to the presence of postoperative dysphagia. Radiographic parameters, including the atlas-dens interval (ADI), O-C2 angle (O-C2a), occipital and external acoustic meatus to axis angle (O-EAa), C2 tilting angle (C2Ta), C2-7 angle (C2-7a), PIA and narrowest oropharyngeal airway space (nPAS), were measured and compared. Simple linear regression and multiple regression analysis were used to evaluate the radiographic predictors for dysphagia. In addition, we used PIA = 90° as a threshold to analyze its effect on predicting dysphagia. RESULTS: Of the 98 patients, 26 exhibited postoperative dysphagia. Preoperatively, PIA in the dysphagia group was significantly higher than that in the nondysphagia group. We detected that O-C2a, O-EAa, PIA and nPAS all decreased sharply in the dysphagia group but increased slightly in the nondysphagia group. The changes were all significant. Through regression analyses, we found that PIA had a similar predictive effect as O-EAa for postoperative dysphagia and changes in nPAS. Additionally, patients with an increasing PIA exhibited no dysphagia, and the sensitivity of PIA <90° in predicting dysphagia reached 88.5%. CONCLUSIONS: PIA could be used as a predictor for postoperative dysphagia in patients undergoing OCF. Adjusting a PIA level higher than the preoperative PIA level could avoid dysphagia. For those who inevitably had decreasing PIA, preserving intraoperative PIA over 90° would help avert postoperative dysphagia. TRIAL REGISTRATION: This trial has been registered in the Medical Ethics Committee of West China Hospital, Sichuan University. The registration number is 762 and the date of registration is Sep. 9 th, 2019.


Assuntos
Transtornos de Deglutição , Fusão Vertebral , Baías , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/cirurgia , China , Transtornos de Deglutição/diagnóstico por imagem , Transtornos de Deglutição/epidemiologia , Humanos , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Fusão Vertebral/efeitos adversos
10.
Spine J ; 21(2): 312-320, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33049411

RESUMO

BACKGROUND CONTEXT: Tranexamic acid (TXA) is widely used in surgery for adolescent idiopathic scoliosis (AIS) and has been proved to be efficacious in reducing intraoperative blood loss (IBL) and the transfusion rate. However, the routine TXA regimen was intraoperative administration alone, in which the concentration of TXA could not cover the whole process of hyperfibrinolysis. And, its ability to control the massive postoperative blood loss (PBL) may be insufficient. Thus, we promoted a multiple-dose regimen of TXA for patients with AIS who underwent surgical correction. PURPOSE: The primary aims were (1) to determine whether the multiple-dose regimen of TXA could reduce PBL and the postoperative transfusion rate, and (2) to compare the efficacy of oral administration with intravenous administration. The secondary aims were (3) to evaluate whether this regimen could alleviate inflammatory response, and (4) to assess the occurrence of drug-related side effects. STUDY DESIGN: Prospective, double-blinded, randomized controlled trial. PATIENT SAMPLE: A total of 108 patients with AIS who underwent posterior scoliosis correction and spinal fusion (PSS) were enrolled in this study. OUTCOME MEASURES: The primary parameters were PBL and postoperative transfusion rate. Other parameters such as total blood loss (TBL), maximum hemoglobin (Hb) decrease, volume of drainage, inflammation markers (interleukin-6 [IL-6] and C-reactive protein [CRP]), and occurrence of complications were also collected and compared. Multiple regression analysis was used to examine the variables that affected PBL. METHODS: Patients were randomized into three groups. All patients received intravenous TXA 50 mg/kg loading dose and 10 mg/kg/h maintenance dose during surgery. Group A received 1 g oral TXA at 4 hours, 10 hours, and 16 hours postoperatively; group B received 0.5 g intravenous TXA at 6 hours, 12 hours, and 18 hours postoperatively; group C received placebo. RESULTS: The mean PBL and postoperative transfusion rate in group A (957.8±378.9 mL, 13.89%) and B (980.3±491.8 mL, 11.11%) were significantly lower than those in group C [1,495.9±449.6 mL, mean differences=538.1 mL, 95% confidence interval (CI), 290.1-786.1 mL, p<0.001; 515.6 mL, 95% CI, 267.6-763.6 mL, p<.001]; (36.11%, p=.029, p=.013). Meanwhile, the mean TBL, maximum Hb decrease, and volume of drainage were also significantly lower in group A and B than in group C. IL-6 and CRP in group A and B were significantly lower than in group C from postoperative days 1 to 3. All these differences were not significant between groups A and B. No drug-related complications were observed in any patient. Multiple regression showed that the application of postoperative TXA and number of screws were significant parameters affecting PBL. CONCLUSIONS: A multiple-dose regimen of TXA, either by oral or intravenous application, could be a safe and effective means of controlling PBL and decreasing the postoperative transfusion rate in patients with AIS who underwent scoliosis surgery. In addition, it could inhibit postoperative inflammatory response.


Assuntos
Antifibrinolíticos , Escoliose , Ácido Tranexâmico , Administração Intravenosa , Adolescente , Antifibrinolíticos/uso terapêutico , Perda Sanguínea Cirúrgica/prevenção & controle , Humanos , Hemorragia Pós-Operatória , Estudos Prospectivos , Escoliose/cirurgia , Resultado do Tratamento
11.
J Geriatr Cardiol ; 17(11): 694-703, 2020 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-33343648

RESUMO

Background: Catheter ablation for ventricular tachycardia (VT) in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) has significantly evolved over the past decade. However, different ablation strategies showed inconsistency in acute and long-term outcomes. Methods: We searched the databases of Medline, Embase and Cochrane Library through October 17, 2019 for studies describing the clinical outcomes of VT ablation in ARVC. Data including VT recurrence, all-cause mortality, acute procedural efficacy and major procedural complications were extracted. A meta-analysis with trial sequential analysis was further performed in comparative studies of endo-epicardial versus endocardial-only ablation. Results: A total of 24 studies with 717 participants were enrolled. The literatures of epicardial ablation were mainly published after 2010 with total ICD implantation of 73.7%, acute efficacy of 89.8%, major complication of 5.2%, follow-up of 28.9 months, VT freedom of 75.3%, all-cause mortality of 1.1% and heart transplantation of 0.6%. Meta-analysis of 10 comparative studies revealed that compared with endocardial-only approach, epicardial ablation significantly decreased VT recurrence (OR: 0.50; 95% CI: 0.30-0.85; P = 0.010), but somehow increased major procedural complications (OR: 4.64; 95% CI: 1.28-16.92; P= 0.02), with not evident improvement of acute efficacy (OR: 2.74; 95% CI: 0.98-7.65; P = 0.051) or all-cause mortality (OR: 0.87; 95% CI: 0.09-8.31; P = 0.90). Conclusion: Catheter ablation for VT in ARVC is feasible and effective. Epicardial ablation is associated with better long-term VT freedom, but with more major complications and unremarkable survival or acute efficacy benefit.

12.
World J Clin Cases ; 8(20): 4908-4916, 2020 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-33195660

RESUMO

BACKGROUND: The global pandemic of coronavirus disease 2019 pneumonia poses a particular challenge to the emergency surgical treatment of elderly patients with high-risk acute abdominal diseases. Elderly patients are a high-risk group for surgical treatment. If the incarceration of gallstones cannot be relieved, emergency surgery is unavoidable. CASE SUMMARY: We report an 89-year-old male patient with acute gangrenous cholecystitis and septic shock induced by incarcerated cholecystolithiasis. He had several coexisting, high-risk underlying diseases, had a history of radical gastrectomy for gastric cancer, and was taking aspirin before the operation. Nevertheless, he underwent emergency laparoscopic cholecystectomy, with maintenance of postoperative heart and lung function, successfully recovered, and was discharged on day 8 after the operation. CONCLUSION: Emergency surgery for elderly patients with acute abdominal disease is safe and feasible during the coronavirus disease 2019 pandemic, the key is to abide strictly by the hospital's epidemic prevention regulations, fully implement the epidemic prevention procedure for emergency surgery, fully prepare before the operation, accurately perform the operation, and carefully manage the patient postoperatively.

13.
Small ; 16(43): e2003096, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33015944

RESUMO

Configuring metal single-atom catalysts (SACs) with high electrocatalytic activity and stability is one efficient strategy in achieving the cost-competitive catalyst for fuel cells' applications. Herein, the atomic layer deposition (ALD) strategy for synthesis of Pt SACs on the metal-organic framework (MOF)-derived N-doped carbon (NC) is proposed. Through adjusting the ALD exposure time of the Pt precursor, the size-controlled Pt catalysts, from Pt single atoms to subclusters and nanoparticles, are prepared on MOF-NC support. X-ray absorption fine structure spectra determine the increased electron vacancy in Pt SACs and indicate the Pt-N coordination in the as-prepared Pt SACs. Benefiting from the low-coordination environment and anchoring interaction between Pt atoms and nitrogen-doping sites from MOF-NC support, the Pt SACs deliver an enhanced activity and stability with 6.5 times higher mass activity than that of Pt nanoparticle catalysts in boosting the oxygen reduction reaction (ORR). Density functional theory calculations indicate that Pt single atoms prefer to be anchored by the pyridinic N-doped carbon sites. Importantly, it is revealed that the electronic structure of Pt SAs can be adjusted by adsorption of hydroxyl and oxygen, which greatly lowers free energy change for the rate-determining step and enhances the activity of Pt SACs toward the ORR.

14.
Nanoscale Horiz ; 5(11): 1453-1466, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33103682

RESUMO

The substantial capacity gap between available anode and cathode materials for commercial Li-ion batteries (LiBs) remains, as of today, an unsolved problem. Oxygen vacancies (OVs) can promote Li-ion diffusion, reduce the charge transfer resistance, and improve the capacity and rate performance of LiBs. However, OVs can also lead to accelerated degradation of the cathode material structure, and from there, of the battery performance. Understanding the role of OVs for the performance of layered lithium transition metal oxides holds great promise and potential for the development of next generation cathode materials. This review summarises some of the most recent and exciting progress made on the understanding and control of OVs in cathode materials for Li-ion battery, focusing primarily on Li-rich layered oxides. Recent successes and residual unsolved challenges are presented and discussed to stimulate further interest and research in harnessing OVs towards next generation oxide-based cathode materials.

15.
Adv Mater ; 32(43): e2004835, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33000881

RESUMO

Elemental 2D materials with fascinating characteristics are regarded as an influential portion of the 2D family. Iodine is as a typical monoelemental molecular crystal and exhibits great prospects of applications. To realize 2D iodine, not only is it required to separate the weak interlayer van der Waals interactions, but also to reserve the weak intramolecular halogen bonds; thus, 2D iodine is still unexploited until now. Herein, atomically thin iodine nanosheets (termed "iodinene") with the thickness around 1.0 nm and lateral sizes up to hundreds of nanometers are successfully fabricated by a liquid-phase exfoliation strategy. When used for the cathode of rechargeable sodium-ion batteries, the ultrathin iodinene exhibits superb rate properties with a high specific capacity of 109.5 mA h g-1 at the high rate of 10 A g-1 owing to its unique 2D ultrathin architecture with remarkably enhanced pseudocapacitive behavior. First-principles calculations reveal that the diffusion of sodium ions in few-layered iodinene changes from the original horizontal direction in bulk to the vertical with a small energy barrier of 0.07 eV because of the size effect. The successful preparation and intensive structural investigation of iodinene paves the way for the development of novel iodine-based science and technologies.

16.
Dalton Trans ; 49(37): 12918-12928, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-32990705

RESUMO

Photoreduction of molecular CO2 by solar light into added-value fuels or chemical feedstocks is an appealing strategy to simultaneously overcome environmental problems and energy challenges. However, multiple reaction steps and a large number of possible products have significantly hindered the development of highly selective catalysts capable of delivering CO2 conversion with high efficiency. Recently, several strategies associated with different conversion mechanisms have been proposed to improve the activity and product selectivity of CO2 photocatalysts. These are based on development of low dimensional nanomaterials, defect or facet engineering, design of tailored heterostructures, and carrier conductivity enhancement. In spite of impressive progress in the field, real-world applications are yet to be delivered. To sustain further research in this promising field, here we provide a short frontier of recent advances in activity and selectivity of CO2 reduction photocatalysts, together with a critical discussion of further avenues of research in this field.

17.
Cancer Med ; 9(21): 8004-8019, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32931665

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) remains one of the most common cancers worldwide and tends to be detected at an advanced stage. More effective biomarkers for HCC screening and prognosis assessment are needed and the mechanisms of HCC require further exploration. The role of MAOA in HCC has not been intensively investigated. METHODS: In-house tissue microarrays, genechips, and RNAsequencing datasets were integrated to explore the expression status and the clinical value of MAOA in HCC. Immunohistochemical staining was utilized to determine MAOA protein expression. Intersection genes of MAOA related co-expressed genes and differentially expressed genes were obtained to perform functional enrichment analyses. In vivo experiment was conducted to study the impact of traditional Chinese medicine nitidine chloride (NC) on MAOA in HCC. RESULTS: MAOA was downregulated and possessed an excellent discriminatory capability in HCC patients. Decreased MAOA correlated with poor prognosis in HCC patients. Downregulated MAOA protein was relevant to an advanced TNM stage in HCC patients. Co-expressed genes that positively related to MAOA were clustered in chemical carcinogenesis, where CYP2E1 was identified as the hub gene. In vivo experiment showed that nitidine chloride significantly upregulated MAOA in a nude mouse HCC model. CONCLUSIONS: A decreased MAOA level is not only correlated with aggressive behaviors in males but also serves as a promising biomarker for the diagnosis and prognosis of HCC patients. Moreover, MAOA may play a role in AFB1 toxic transformation through its synergistic action with co-expressed genes, especially CYP3A4. MAOA also serves as a potential therapy target of NC in HCC patients.


Assuntos
Biomarcadores Tumorais/análise , Carcinoma Hepatocelular/enzimologia , Neoplasias Hepáticas/enzimologia , Monoaminoxidase/análise , Animais , Antineoplásicos Fitogênicos/farmacologia , Benzofenantridinas/farmacologia , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Citocromo P-450 CYP2E1/genética , Citocromo P-450 CYP2E1/metabolismo , Citocromo P-450 CYP3A/genética , Citocromo P-450 CYP3A/metabolismo , Bases de Dados Genéticas , Regulação para Baixo , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Camundongos Nus , Monoaminoxidase/genética , Estadiamento de Neoplasias , Análise de Sequência com Séries de Oligonucleotídeos , Valor Preditivo dos Testes , Mapas de Interação de Proteínas , RNA-Seq , Análise Serial de Tecidos , Ensaios Antitumorais Modelo de Xenoenxerto
18.
World Neurosurg ; 144: e916-e925, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32987173

RESUMO

BACKGROUND: Previous studies have reported the progression of deformity in patients with adolescent idiopathic scoliosis after implant removal. However, for patients with congenital scoliosis, few studies have investigated the prognosis after implant removal. METHODS: We observed 24 patients with congenital scoliosis, who underwent implant removal, for at least 3 years. Radiographic parameters and demographic data were compared to evaluate whether implant removal would lead to deformity progression. RESULTS: Four of the 24 patients (16.7%) suffered correction loss and underwent revision surgery (RS). All correction losses occurred within 12 months of implant removal. The average curve of fixed segments (9.84° ± 7.22° to 16.42° ± 16.79°; P = 0.017) and kyphosis of fixed segments (10.46° ± 13.42° to 18.98° ± 25.99°; P = 0.03) increased significantly throughout the follow-up. After excluding patients who underwent RS, the changes in curve of fixed segments (9.10°-11.58°) and kyphosis of fixed segments (8.50°-9.24°) were all within the measurement error. The coronal and sagittal balance maintained during the follow-up. Through comparison, we thought that the younger age and lower Risser's grade with larger scoliosis might be risk factors for correction loss. CONCLUSIONS: Implant removal after fusion surgery for congenital scoliosis may present loss of correction and require RS, thus preserving implants is recommended. When removal of instrumentation is inevitable, parents and patients should be counseled for potential loss of correction and RS, and patients should be monitored for the progression of deformity.


Assuntos
Remoção de Dispositivo , Dispositivos de Fixação Ortopédica , Escoliose/congênito , Escoliose/cirurgia , Fusão Vertebral , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Reoperação , Estudos Retrospectivos , Escoliose/diagnóstico por imagem , Escoliose/epidemiologia , Fusão Vertebral/instrumentação , Fusão Vertebral/métodos , Resultado do Tratamento
19.
Proc Natl Acad Sci U S A ; 117(36): 21906-21913, 2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32848064

RESUMO

Development of novel and robust oxygen evolution reaction (OER) catalysts with well-modulated atomic and electronic structure remains a challenge. Compared to the well-known metal hydroxides or (oxyhydr)oxides with lamellar structure, delafossites (ABO2) are characterized by alternating layers of A cations and edge-sharing BO2 octahedra, but are rarely used in OER due to their poor electron conductivity and intrinsic activity. Here, we propose a delafossite analog by mutation of metal oxyhydroxide and delafossite based on first-principles calculations. Modulation on the electronic structure due to distortion of the original crystal field of the BO2 layers is calculated to enhance electron conductivity and catalytic activity. Inspired by the theoretical design, we have experimentally realized the delafossite analog by electrochemical self-reconstruction (ECSR). Operando X-ray absorption spectroscopy and other experimental techniques reveal the formation of delafossite analog with Ag intercalated into bimetallic cobalt-iron (oxyhydr)oxide layers from a metastable precursor through amorphization. Benefitting from the featured local electronic and geometric structures, the delafossite analog shows superior OER activity, affording a current density of 10 mA⋅cm-2 at an overpotential of 187 mV and an excellent stability (300 h) in alkaline conditions.

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