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1.
Nano Lett ; 24(1): 472-478, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38146703

RESUMO

Strain engineering has been used as an efficient method to modulate various properties of quantum materials and electronic devices. One may establish piezo effects based on a disciplined response to the strain in multifunctional nanosystems. Inspired by a recent theoretical proposal on the interesting piezomagnetism and C-paired valley polarization in the V2Se2O monolayer, we predict a stable altermagnetic Janus monolayer V2SeTeO using density functional theory calculations. It exhibits a novel "multipiezo" effect combining piezoelectricity, piezovalley, and piezomagnetism. Most interestingly, the valley polarization and the net magnetization under strain in V2SeTeO exceed these in V2Se2O, along with the additional large piezoelectric coefficient. The "multipiezo" effect makes Janus monolayer V2SeTeO as a tantalizing material for potential applications in nanoelectronics, optoelectronics, spintronics, and valleytronics.

2.
Phys Chem Chem Phys ; 26(12): 9170-9178, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-37850421

RESUMO

Two-dimensional ferromagnets with high spin-polarization at ambient temperature are of considerable interest because they might be useful for making nanoscale spintronic devices. We report that even though bulk phases of MnO2 are generally antiferromagnetic with low ordering temperatures, the corresponding MnO2 and MnS2 monolayers are ferromagnetic, and MnS2 is a high temperature half metallic ferromagnet. Based on first-principles calculations, we find that the MnO2 monolayer is an intrinsic ferromagnetic semiconductor with a Curie temperature TC of ∼300 K, while the half-metallic MnS2 monolayer has a remarkably high TC of ∼1150 K. Both compounds have substantial magnetocrystalline anisotropy, out of plane in the case of MnO2 monolayers, and in plane along the b-axis of orthorhombic MnS2 monolayer. Interestingly, a metal-insulator phase transition occurs in the MnS2 monolayer when the applied biaxial strain is beyond -2%. Tuning near this metal-insulator transition offers additional possibilities for devices. The present work shows that MnX2 (X = O, S) monolayers have the properties required for ultrathin nano-spintronic devices.

3.
Int J Mol Sci ; 25(2)2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38279347

RESUMO

The copolymers of carbon monoxide (CO) and ethylene, namely aliphatic polyketones (PKs), have attracted considerable attention due to their unique property and degradation. Based on the arrangement of the ethylene and carbonyl groups in the polymer chain, PKs can be divided into perfect alternating and non-perfect alternating copolymers. Perfect alternating PKs have been previously reviewed, we herein focus on recent advances in the synthesis of PKs without a perfect alternating structure including non-perfect alternating PKs and PE with in-chain ketones. The chain structure of PKs, catalytic copolymerization mechanism, and non-alternating polymerization catalysts including phosphine-sulfonate Pd, diphosphazane monoxide (PNPO) Pd/Ni, and phosphinophenolate Ni catalysts are comprehensively summarized. This review aims to enlighten the design of ethylene/CO non-alternating polymerization catalysts for the development of new polyketone materials.


Assuntos
Monóxido de Carbono , Etilenos , Polimerização , Monóxido de Carbono/química , Etilenos/química , Polímeros/química
4.
Angew Chem Int Ed Engl ; 63(20): e202317463, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38503689

RESUMO

Controllably regulating the electrostatic bilayer of nanogold colloids is a significant premise for synthesizing spherical nucleic acid (SNA) and building ordered plasmonic architectures. We develop a facile acoustic levitation reactor to universally synthesize SNAs with an ultra-high density of DNA strands, which is even higher than those of various state-of-the-art methods. Results reveal a new mechanism of DNA grafting via acoustic wave that can reconfigure the ligands on colloidal surfaces. The acoustic levitation reactor enables substrate-free three-dimentional (3D) spatial assembly of SNAs with controllable interparticle nanogaps through regulating DNA lengths. This kind of architecture may overcome the plasmonic enhancement limits by blocking electron tunneling and breaking electrostatic shielding in dried aggregations. Finite element simulations support the architecture with 3D spatial plasmonic hotspot matrix, and its ultrahigh surface-enhanced Raman scattering (SERS) capability is evidenced by in situ untargeted tracking of biomolecular events during photothermal stimulation (PTS)-induced cell death process. For biomarker diagnosis, the conjugation of adenosine triphosphate (ATP) aptamer onto SNAs enables in situ targeted tracking of ATP during PTS-induced cell death process. Particularly, the CD71 receptor and integrin α3ß1 protein on PL45 cell membrance could be well distinguished by label-free SERS fingerprints when using specific XQ-2d and DML-7 aptamers, respectively, to synthesize SNA architectures. Our current acoustic levitation reactor offers a new method for synthesizing SNAs and enables both targeted and untargeted SERS analysis for tracking molecular events in living systems. It promises great potentials in biochemical synthesis and sensing in future.


Assuntos
Ouro , Análise Espectral Raman , Ouro/química , DNA/química , Nanopartículas Metálicas/química , Acústica , Humanos , Propriedades de Superfície , Trifosfato de Adenosina/química
5.
Appl Opt ; 62(21): 5707-5713, 2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37707187

RESUMO

Digital signal coding based on the combination of vortex beam orbital angular momentum (OAM) and vortex optical phase information has made many achievements in optical communication. The accuracy of the vortex optical phase is the key to improving the efficiency of communication coding. In this regard, we propose a depth learning model based on the generative adversarial network (GAN) to accurately recover the phase image information of fractional vortex patterns at any diffraction distance, thus solving the problem that it is difficult to determine the phase information of fractional vortex patterns at different transmission distances due to the phase evolution. Compared with other depth learning methods, the phase recovery result of GAN is not affected by the diffraction distance, which is the first time we know that this method is applied to the fractional order optical vortex. Our work provides a new idea for the accurate identification of multi-singular structured light.

6.
Eur Neurol ; 86(3): 193-206, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36972578

RESUMO

INTRODUCTION: Subarachnoid hemorrhage (SAH) is a severe cerebrovascular event with high mortality and disability rate. Neuroinflammation is involved in the brain injury after SAH, but the exact association between SAH progression and peripheral blood inflammatory factors is unknown. Therefore, to determine the relationship between inflammatory factors and the prognosis of SAH, we performed a meta-analysis. METHOD: A systematic literature review was conducted in PubMed, Embase, and the Cochrane Library. Studies comparing the relationship between inflammatory factors (C-reactive protein [CRP], interleukin-6 [IL-6], interleukin-10 [IL-10], and tumor necrosis factor [TNF-α]) and prognosis of SAH were included in the study. A random-effects meta-analysis was conducted based on mRS, GOS, and the occurrence of cerebral vasospasm, delayed cerebral ischemia, and delayed ischemic neurologic deficits. Sensitivity analysis was performed using the leave-one-out method. The Newcastle-Ottawa Scale (NOS) for case-control studies was used to assess the quality of included studies. For continuous variables, we calculated the mean difference with a 95% confidence interval (CI). RESULTS: 1,469 patients from 18 case-control studies met the inclusion criteria. The results found that patients in the good outcome group had significantly lower CRP levels than those in the poor outcome group (SMD: -1.15, 95% CI: -1.64 to -0.66, p < 0.00001, I2 = 87%), and peripheral IL-6 levels were significantly lower in SAH patients with the good functional outcome than those with the poor functional outcome (SMD: -0.99, 95% CI: -1.48 to -0.51, p < 0.0001, I2 = 88%). As for IL-10 (SMD: -0.28, 95% CI: -0.97 to 0.42, p = 0.43, I2 = 88%) and TNF-α (SMD: -0.40, 95% CI: -0.98 to 0.19, p = 0.18, I2 = 79%), due to the small number of studies, heterogeneity, and uncontrollable factors, robust conclusions cannot be drawn. CONCLUSION: SAH patients with good prognoses have significantly lower peripheral CRP and IL-6 levels. In addition, due to the small number of studies, heterogeneity, and uncontrollable factors, robust conclusions cannot be drawn for IL-10 and TNF-α. More high-quality studies are needed in the future to provide more specific recommendations for the clinical practice of inflammatory factors.


Assuntos
Hemorragia Subaracnóidea , Humanos , Hemorragia Subaracnóidea/complicações , Interleucina-10 , Interleucina-6 , Fator de Necrose Tumoral alfa , Prognóstico , Proteína C-Reativa
7.
Heart Surg Forum ; 26(1): E001-E008, 2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36856513

RESUMO

BACKGROUND: The long-term prognosis of patients with acute type A aortic dissection (AAD) is poor, despite emergency surgical treatment. Therefore, it is imperative to evaluate patient risk factors to improve the prognosis. The aim of this study was to analyze the ability of the uric acid-to-albumin ratio (UAR) to predict the long-term mortality of patients with type A AAD after surgery. METHODS AND RESULTS: A total of 289 patients with type A AAD who had received surgical treatment was enrolled in this study. Peripheral blood samples were collected before anesthesia induction. All patients were divided into the UAR < 9.875 group and the UAR ≥ 9.875 group, and mortality significantly differed between the two groups. The patients were further divided into survival and non-survival groups, according to whether death occurred after the procedure based on a one-year follow up. Factors, including age, hypertension, albumin, UAR, and D-dimer, differed significantly between the survival and non-survival groups. The independent risk factors for long-term death in patients with type A AAD were analyzed by univariable and multivariable COX regression analyses, and the predictive value of these indices for postoperative mortality was assessed based on the receiver operating characteristic (ROC) curves. Preoperative UAR (HR 1.904, 95% CI, 1.097 to 3.305; P < 0.05), D-dimer (HR, 1.991,95% CI, 1.116 to 3.554; P < 0.05 ), and age (HR 2.216, 95% CI, 1.287 to 3.815; P < 0.05) were identified as independent risk factors for one-year mortality in patients with Type A AAD. The area under the ROC curve (AUC) of UAR was 0.618 [95% (0.544, 0.693)], and the sensitivity and specificity were 69.6% and 51.8%, respectively (P = 0.003). The AUC for albumin was 0.349 [95% (0.274, 0.425)], and the sensitivity and specificity were 26.1% and 51.8%, respectively (P = 0.000), The AUC for uric acid was 0.544 [95% (0.470, 0.619)], and the sensitivity and specificity were 78.3% and 34.5%, respectively (P = 0.265). The AUC for UAR + age + D-dimer was 0.751 [95% (0.681, 0.821)], and the sensitivity and specificity were 76.8% and 68.2%, respectively. CONCLUSIONS: UAR in patients with type A AAD may be used as a new independent risk factor for long-term mortality. Its predictive value is superior to that of albumin or uric acid alone. The combination of UAR, age, and D-dimer provide good prognostic value.


Assuntos
Dissecção Aórtica , Ácido Úrico , Humanos , Prognóstico , Albuminas , Anestesia Geral
8.
Yi Chuan ; 45(9): 801-812, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37731234

RESUMO

Nitrogen is critical for peanut growth and development, and symbiotic nodulation and nitrogen fixation is one of the main ways for peanut to obtain nitrogen. The influence of exogenous nitrogen on nodule nitrogen fixation involves complex regulatory mechanisms, revealing the regulatory mechanisms of nitrogen on nodule nitrogen fixation is of great significance for realizing the potential of biological nitrogen fixation. In this review, we summarize the mechanism of "Crack entry" in the formation of peanut root nodule, the mechanism of symbiotic nodulation and quantitative regulation of peanut, and the regulatory mechanism of nitrogen affecting peanut nodulation. At present, the molecular mechanism by which nitrogen affects the interaction between Bradyrhizobium and peanut, thereby regulating nodulation, is still unclear. Therefore, future research should focus on the signal exchange, nodule number regulation, and nutrient exchange mechanism of nitrogen effects on Bradyrhizobium and peanut, which would provide a theoretical basis for improving nodule nitrogen fixation efficiency and peanut yield, and reduce chemical nitrogen fertilizer application.


Assuntos
Arachis , Nitrogênio
9.
Angew Chem Int Ed Engl ; 62(17): e202300028, 2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-36809685

RESUMO

As a momentum-independent spin configuration, persistent spin texture (PST) could avoid spin relaxation and play an advantageous role in spin lifetime. Nevertheless, manipulation of PST is a challenge due to the limited materials and ambiguous structure-property relationships. Herein, we present electrically switchable PST in a new 2D perovskite ferroelectric, (PA)2 CsPb2 Br7 (where PA is n-pentylammonium), which has a high Curie temperature of 349 K, evident spontaneous polarization (3.2 µC cm-2 ) and a low coercive electric field of 5.3 kV cm-1 . The combination of symmetry-breaking in ferroelectrics and effective spin-orbit field facilitates intrinsic PST in the bulk and monolayer structure models. Strikingly, the directions of spin texture are reversible by switching the spontaneous electric polarization. This electric switching behavior relates to the tilting of PbBr6 octahedra and the reorientation of organic PA+ cations. Our studies on ferroelectric PST of 2D hybrid perovskites afford a platform for electrical spin texture manipulation.

10.
J Res Med Sci ; 28: 82, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38292336

RESUMO

Background: Calcitonin gene-related peptides (CGRP) have been considered a new effective means to prevent and treat migraine. Eptinezumab is a new class of CGRP antagonists that has been ratified for clinical treatment. The purpose of this systematic review was to assess and contrast the therapeutic effect and safety of eptinezumab in the management of migraine in comparison with a placebo. Materials and Methods: We systematically searched PubMed, Embase, Cochrane Library, and the US National Institutes of Health Clinical Trials Registry from the earliest date to February 16, 2023, for randomized controlled trials (RCTs). The mean difference (MD) and risk ratio (RR) were chosen to assess clinical indicators. Results: In total, there were 2, 739 patients in four RCTs, who were ultimately included. Our summarized results showed that eptinezumab had better healing efficacy compared to placebo with respect to monthly migraine days (MD = -1.56, 95% confidence interval [CI]: -2.32, -0.79, P < 0.001), improving ≥75% migraine responder rate (RR = 1.80, 95% CI: 1.40, 2.33, P < 0.001), ≥50% migraine responder rate (RR = 1.46, 95% CI: 1.33, 1.61, P < 0.001), and 100% migraine responder rate (RR = 2.41, 95% CI: 1.08, 5.38, P < 0.001). Furthermore, compared with placebo, there was no significant increase for treatment-related adverse events (RR = 1.01, 95% CI 0.94, 1.10, P = 0.71) and serious AEs (RR = 0.93, 95% CI 0.46, 1.90, P = 0.84). It was found that all dosages except for 10 mg had significant efficacy compared with placebo, especially 300 mg (P < 0.001). Conclusion: Eptinezumab has good healing efficacy and insignificant adverse effects in treating migraine, particularly the dosage of 300 mg.

11.
Gut ; 71(2): 238-253, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34836916

RESUMO

OBJECTIVE: Helicobacter pylori infection is mostly a family-based infectious disease. To facilitate its prevention and management, a national consensus meeting was held to review current evidence and propose strategies for population-wide and family-based H. pylori infection control and management to reduce the related disease burden. METHODS: Fifty-seven experts from 41 major universities and institutions in 20 provinces/regions of mainland China were invited to review evidence and modify statements using Delphi process and grading of recommendations assessment, development and evaluation system. The consensus level was defined as ≥80% for agreement on the proposed statements. RESULTS: Experts discussed and modified the original 23 statements on family-based H. pylori infection transmission, control and management, and reached consensus on 16 statements. The final report consists of three parts: (1) H. pylori infection and transmission among family members, (2) prevention and management of H. pylori infection in children and elderly people within households, and (3) strategies for prevention and management of H. pylori infection for family members. In addition to the 'test-and-treat' and 'screen-and-treat' strategies, this consensus also introduced a novel third 'family-based H. pylori infection control and management' strategy to prevent its intrafamilial transmission and development of related diseases. CONCLUSION: H. pylori is transmissible from person to person, and among family members. A family-based H. pylori prevention and eradication strategy would be a suitable approach to prevent its intra-familial transmission and related diseases. The notion and practice would be beneficial not only for Chinese residents but also valuable as a reference for other highly infected areas.


Assuntos
Saúde da Família , Infecções por Helicobacter/prevenção & controle , Helicobacter pylori , Controle de Infecções/organização & administração , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , China , Consenso , Técnica Delphi , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/transmissão , Humanos , Lactente , Pessoa de Meia-Idade , Adulto Jovem
12.
Chembiochem ; 23(3): e202100587, 2022 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-34796597

RESUMO

G-triplex (G3) structures formed with three consecutive G-tracts have recently been identified as a new emerging guanine-rich DNA fold. There could likely be a wide range of biological functions for G3s as occurring for G-quadruplex (G4) structures formed with four consecutive G-tracts. However, in comparison to the many reports on G4 nanoassemblies that organize monomers together in a controllable manner, G3-favored nanoassemblies have yet to be explored. In this work, we found that a natural alkaloid of sanguinarine can serve as a dynamic ligand glue to reversibly switch the dimeric nanoassemblies of the thrombin binding aptamer G3 (TBA-G3). The glue planarity was considered to be a crucial factor for realizing this switching. More importantly, external stimuli including pH, sulfite, O2 and H2 O2 can be employed as common regulators to easily modulate the glue's adhesivity for constructing and destructing the G3 nanoassemblies as a result of the ligand converting between isoforms. However, this assembly behavior does not occur with the counterpart TBA-G4. Our work demonstrates that higher-order G3 nanoassemblies can be reversibly operated by manipulating ligand adhesivity. This provides an alternative understanding of the unique behavior of guanine-rich sequences and focuses attention on the G3 fold since the nanoassembly event investigated herein might occur in living cells.


Assuntos
Aptâmeros de Nucleotídeos/química , DNA/química , Quadruplex G
13.
Hum Psychopharmacol ; 37(3): e2825, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34739739

RESUMO

OBJECTIVE: In recent years, interest in using lysergic acid diethylamide (LSD) in psychiatric research and corresponding therapy has increased rapidly. In this meta-analysis, we explored the effects of LSD on healthy subjects with respect to subjective drug effects, blood pressure, heart rate, body temperature and side effects. METHOD: PubMed, Embase, and the Cochrane Library were searched from January 2010 to December 2020 for randomized controlled trials (RCTs) on the effects of LSD in healthy people. Subsequently, 5 RCTs with 132 healthy people which focused on the effects of LSD were enrolled in our study. RESULT: We found that taking 50, 100 and 200 mcg LSD doses were associated with a significant increase in the maximal difference from the baseline compared to the placebo group among the outcomes of AMRS (Adjective Mood Rating Scale) score. Significant differences existed between the LSD and placebo groups when taking 100 and 200 mcg LSD in acute adverse effects (100 mcg: SMD = .97, 95% confidence interval [CI], .50, 1.44, Z = 4.04, p < .001; 200 mcg: SMD = 1.18, 95% CI, 0.65, 1.72, Z = 4.32, p < .001). CONCLUSIONS: Meta-analysis of the subjective effects of LSD in healthy people revealed moderate significant effect sizes in favor of LSD with no significant adverse effects. A 100 mcg dose of LSD has potential for use in psychological-assisted therapy and may improve the mental fitness of patients with disease-related psychiatric distress. Additional clinical trials are necessary to explore the efficacy and safety of LSD as a psychological-assisted therapy.


Assuntos
Alucinógenos , Dietilamida do Ácido Lisérgico , Afeto , Estudos Cross-Over , Alucinógenos/efeitos adversos , Voluntários Saudáveis , Humanos , Dietilamida do Ácido Lisérgico/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto
14.
Neurol Sci ; 43(6): 3565-3581, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35243548

RESUMO

BACKGROUND: As one kind of disease-modifying therapies, sphingosine-1-phosphate receptor (S1PR) modulators such as fingolimod, ozanimod, and siponimod have been approved or are being developed to treat multiple sclerosis (MS). Several randomized controlled trials (RCT) have been implemented to compare the efficacy and safety of S1PR modulators versus interferon beta in the treatment of people with relapsing-remitting multiple sclerosis (RRMS). METHOD: We searched RCTs which were implemented from January 2010 to June 2020 by searching PubMed, Embase, Cochrane Library databases, and the Central Register of Controlled Trials. Finally, five RCTs were included in our study after carefully choosing. RESULT: We pooled 4304 patients from 5 RCTs. The primary outcome was the annualized relapse rate. We found that the annualized relapse rate in the S1PR modulator group is 20% less than that in the interferon beta group (95%CI, - 0.32 to - 0.07, P = 0.002). S1PR modulators led to a significant reduction in number of new or enlarging T2 lesions per scan and number of gadolinium-enhancing lesions compared with interferon beta. Moreover, S1PR modulators can also improve 54-item multiple sclerosis quality of life (MSQOL-54) physical health composite score (P = 0.0005). CONCLUSION: S1PR modulators exhibited good efficacy and safety for the treatment of RRMS compared with interferon beta. According to follow-up trials, S1PR modulators can improve MSQOL-54 physical health composite score so that it may be beneficial to neurological recovery which need more research to confirm.


Assuntos
Esclerose Múltipla Recidivante-Remitente , Esclerose Múltipla , Moduladores do Receptor de Esfingosina 1 Fosfato , Humanos , Interferon beta-1a/uso terapêutico , Interferon beta/uso terapêutico , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto , Recidiva , Receptores de Esfingosina-1-Fosfato
15.
Eur Neurol ; 85(2): 85-94, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34818658

RESUMO

INTRODUCTION: The combination of mechanical thrombectomy (MT) and intravenous thrombolysis (IVT) is more effective than IVT alone in patients with large vessel occlusion, which has been proven in recent studies. However, there are still debates over whether IVT benefits patients treated with only direct mechanical thrombectomy (dMT). METHODS: PubMed, Embase, and Cochrane Library were searched on June 15, 2021, for randomized controlled trials (RCTs). Seven RCTs with 2,143 patients were enrolled in our study. RESULTS: MT combined with IVT had comparable efficacy and safety outcome compared with dMT in proximal anterior circulation occlusion at 90 days. For the primary outcome, pooled data showed no significant difference in the modified Rankin Scale (mRS) 0-2 at 90 days between the dMT and MT+IVT groups (pooled odds ratio 0.96, 95% confidence interval, 0.79, 1.17, p = 0.39). As for the mRS score 0-1 at 90 days, the degree of benefit conferred by dMT was substantial: for every 100 patients treated, the number of patients which had an excellent outcome in the dMT group was 10 higher than that of the MT+IVT group. CONCLUSION: In this meta-analysis including 7 RCTs, MT had comparable consequences to bridging treatment in efficacy and safety outcomes for patients with ischemic stroke caused by the occlusion of proximal anterior circulation, irrespective of geographical location. These findings support the adoption of dMT in acute ischemic stroke treatments and have higher cost-effectiveness in global applications.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Isquemia Encefálica/tratamento farmacológico , Fibrinolíticos/uso terapêutico , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Acidente Vascular Cerebral/tratamento farmacológico , Trombectomia , Terapia Trombolítica , Resultado do Tratamento
16.
Nano Lett ; 21(23): 10139-10145, 2021 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-34543026

RESUMO

Linear magnetoresistance (LMR) is usually observed in topological quantum materials and plausibly connected with the topologically nontrivial surface state with Dirac-cone-like linear dispersion because the frequently encountered large Hall resistivity can be trivially mixed into the LMR via charge inhomogeneity. Herein, by applying an optimal gate voltage to nodal-line semimetal ZrGeSe two-dimensional (2D) layers with specific thicknesses, we observe a giant nonsaturated LMR of 8 × 104% at 2 K and a magnetic field of 9 T. This giant LMR is accompanied by a very small Hall resistivity, which is inconsistent with the charge inhomogeneity mechanism. Our systematic results confirm that the giant LMR is maximized when the topological semimetal is in the "even-metal" regime and suppressed upon evolution to the normal "odd-metal" regime. The "even-to-odd" transition is universal regardless of the thicknesses of the crystals. A comparison with Abrikosov's quantum LMR theory indicates that the observed LMR cannot be trivial.

17.
Opt Lett ; 46(23): 5802-5805, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34851894

RESUMO

We study the instantaneous response of stimulated Brillouin scattering (SBS) in a fiber system phase modulated by a binary sequence waveform. The buildup time constant of SBS kinetics is investigated analytically and experimentally. A series of binary sequences with adjustable dwell time and sequence period is constructed in order to examine both buildup and suppressing processes for SBS in 15 m short fiber. For a fiber system with SBS buildup time constant within several nanoseconds, the Stokes intensity can be effectively suppressed by implementing a binary sequence phase modulation with a dwell time close to or even less than the buildup time constant. Stokes intensity can be suppressed in several sequence periods, which exhibit a damped-oscillation-like trend.

18.
Pharmacol Res ; 167: 105522, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33667687

RESUMO

Excessive daytime sleepiness is considered as the prominent symptom in narcolepsy and Obstructive Sleep Apnea (OSA). Pitolisant is a novel selective histamine H3 receptor antagonist approved for improving excessive daytime sleepiness. The meta-analysis is conducted to assess the efficacy and safety of pitolisant versus placebo for excessive daytime sleepiness in narcolepsy and OSA. PubMed, Embase and Cochrane Library databases were searched from earliest date to November 2020 for randomized controlled trials (RCTs). The primary outcomes were mean changes in Epworth Sleepiness Scale (ESS), mean sleep latency, European quality-of-life questionnaire (EQ-5D), and risk ratio of treatment-emergent adverse events (TEAEs). We pooled 678 patients from four RCTs and found pitolisant significantly decreased ESS by mean difference (MD) of - 2.86 points (95% CI: -3.75 to -1.96), increased mean sleep latency by MD of 3.14 min (95% CI: 2.18-4.11), and increased EQ-5D by MD of 3.32 points (95% CI: 0.26-6.39) compared with placebo. The risk ratio of TEAE was 1.37 (95% CI: 1.08-1.74). Insomnia was the only TEAE significantly associated with pitolisant treatment. In conclusion, pitolisant showed great efficacy and controllable security versus placebo for excessive daytime sleepiness in narcolepsy and OSA. Compared with narcolepsy, patients with OSA were deemed to benefit more from pitolisant especially in terms of improving mobility and quality of life of patients without continuous positive airway pressure therapy.


Assuntos
Distúrbios do Sono por Sonolência Excessiva/tratamento farmacológico , Antagonistas dos Receptores Histamínicos/uso terapêutico , Narcolepsia/complicações , Piperidinas/uso terapêutico , Apneia Obstrutiva do Sono/complicações , Distúrbios do Sono por Sonolência Excessiva/etiologia , Antagonistas dos Receptores Histamínicos/efeitos adversos , Humanos , Piperidinas/efeitos adversos , Efeito Placebo , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto
19.
Analyst ; 146(19): 5866-5872, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34570847

RESUMO

DNA-tuned dye assemblies have received considerable attention toward developing various devices. Owing to easy conformation implementation, G-quadruplexes (G4s) have been extensively used as initiators to grow dye assemblies with controllable chiralities. However, programmed chirality regulation of dye assemblies for a given G4 sequence has not been realized in a straightforward manner. In this work, we replaced a middle guanine in the G-tracts of a human telomeric G4 with an apurinic site (AP site) to meet the programmed dye assemblies. Although all of the AP site replacements altered the G4 conformation from the hybrid to the antiparallel folding, the handedness of pinacyanol (PIN) assemblies grown on the AP site-containing G4 was programmably regulated. The G4 with the AP site at the 5'-most G-tract grew right-handed assemblies, while that with the AP site at the 3'-most G-tract grew left-handed assemblies. The handedness of assemblies almost totally mirrored each other within 450-700 nm. Interestingly, we found that the AP site provided a specific binding site for guanosine and guanine, and this binding event sensitively broke the chiral assemblies. Thus, dye assembly-based sensors can be easily established based on the chiral responses with a high selectivity and sensitivity. Our work first demonstrates the AP site programmed chirality regulation of G4-grown dye assemblies and will find wide application in chiral devices.


Assuntos
Quadruplex G , DNA , Guanina , Guanosina , Humanos , Telômero
20.
Neurosurg Rev ; 44(3): 1665-1673, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32767042

RESUMO

Ependymomas occurring in the upper cervical spinal cord (above the level of the C4 segment) are rare entities with great therapeutic challenges. This study was aimed to investigate the clinicoradiological characteristics and the prognosis in a large cohort of upper cervical ependymomas from a single institution. This retrospective study enrolled 155 patients with primary ependymomas in the upper cervical spinal cord. The pre- and post-operative clinical and magnetic resonance imaging profiles were collected. The neurological outcomes and survival events were evaluated, and potential independent risk factors were analyzed. There were 82 females and 73 males, with an average age of 43.1 ± 11.3 years. Immediately post-operatively, 118 (76.1%) patients experienced neurological deterioration and 32 (20.7%) patients remained unchanged. Three months after surgery, 61 (39.4%) patients showed deteriorated neurological functions compared to the pre-operative baseline levels. After an average follow-up period of 56.0 ± 24.7 months, the neurological functions were worse than the baseline status in 37 (23.9%) patients and improved in 33 (21.3%) patients, respectively. Logistic regression analysis identified that lower age (≤ 42 years) and lower pre-operative MMS (I-II) were independent protective factors for predicting favorable neurological functions. Multivariate Cox regression analysis revealed that incomplete resection was the only independent risk factor associated with a shorter progression-free survival. Age and pre-operative functional status affect the long-term neurological outcomes, and incomplete resection was associated with a shorter survival. Our findings indicate that gross total resection should be the goal of surgical treatment of upper cervical ependymomas.


Assuntos
Medula Cervical/diagnóstico por imagem , Medula Cervical/cirurgia , Ependimoma/diagnóstico por imagem , Ependimoma/cirurgia , Neoplasias da Medula Espinal/diagnóstico por imagem , Neoplasias da Medula Espinal/cirurgia , Adulto , Idoso , Estudos de Coortes , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos/métodos , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento , Adulto Jovem
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