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1.
Nat Methods ; 20(5): 735-746, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37024654

RESUMO

High-speed three-dimensional (3D) intravital imaging in animals is useful for studying transient subcellular interactions and functions in health and disease. Light-field microscopy (LFM) provides a computational solution for snapshot 3D imaging with low phototoxicity but is restricted by low resolution and reconstruction artifacts induced by optical aberrations, motion and noise. Here, we propose virtual-scanning LFM (VsLFM), a physics-based deep learning framework to increase the resolution of LFM up to the diffraction limit within a snapshot. By constructing a 40 GB high-resolution scanning LFM dataset across different species, we exploit physical priors between phase-correlated angular views to address the frequency aliasing problem. This enables us to bypass hardware scanning and associated motion artifacts. Here, we show that VsLFM achieves ultrafast 3D imaging of diverse processes such as the beating heart in embryonic zebrafish, voltage activity in Drosophila brains and neutrophil migration in the mouse liver at up to 500 volumes per second.


Assuntos
Microscopia , Peixe-Zebra , Animais , Camundongos , Imageamento Tridimensional/métodos
2.
Proc Natl Acad Sci U S A ; 120(44): e2310174120, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37883437

RESUMO

α-synuclein (α-Syn) is a presynaptic protein that is involved in Parkinson's and other neurodegenerative diseases and binds to negatively charged phospholipids. Previously, we reported that α-Syn clusters synthetic proteoliposomes that mimic synaptic vesicles. This vesicle-clustering activity depends on a specific interaction of α-Syn with anionic phospholipids. Here, we report that α-Syn surprisingly also interacts with the neutral phospholipid lysophosphatidylcholine (lysoPC). Even in the absence of anionic lipids, lysoPC facilitates α-Syn-induced vesicle clustering but has no effect on Ca2+-triggered fusion in a single vesicle-vesicle fusion assay. The A30P mutant of α-Syn that causes familial Parkinson disease has a reduced affinity to lysoPC and does not induce vesicle clustering. Taken together, the α-Syn-lysoPC interaction may play a role in α-Syn function.


Assuntos
Doença de Parkinson , alfa-Sinucleína , Humanos , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo , Vesículas Sinápticas/metabolismo , Lisofosfatidilcolinas/metabolismo , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Fosfolipídeos/metabolismo
3.
J Comput Chem ; 45(6): 321-330, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-37861354

RESUMO

Cyclometalated Pt(II) complexes are popular phosphorescent emitters with color-tunable emissions. To render their practical applications as organic light-emitting diodes emitters, it is required to develop Pt(II) complexes with high radiative decay rate constant and photoluminescence (PL) quantum yield. Here, a general protocol is developed for accurate predictions of emission wavelength, radiative decay rate constant, and PL quantum yield based on the combination of first-principles quantum mechanical method, machine learning, and experimental calibration. A new dataset concerning phosphorescent Pt(II) emitters is constructed, with more than 200 samples collected from the literature. Features containing pertinent electronic properties of the complexes are chosen and ensemble learning models combined with stacking-based approaches exhibit the best performance, where the values of squared correlation coefficients are 0.96, 0.81, and 0.67 for the predictions of emission wavelength, PL quantum yield and radiative decay rate constant, respectively. The accuracy of the protocol is further confirmed using 24 recently reported Pt(II) complexes, which demonstrates its reliability for a broad palette of Pt(II) emitters.

4.
Am Heart J ; 274: 65-74, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38701961

RESUMO

BACKGROUND: There has not been a consensus on the prothesis sizing strategy in type 0 bicuspid aortic stenosis (AS) patients undergoing transcatheter aortic valve replacement (TAVR). Modifications to standard annular sizing strategies might be required due to the distinct anatomical characteristics. We have devised a downsizing strategy for TAVR using a self-expanding valve specifically for patients with type 0 bicuspid AS. The primary aim of this study is to compare the safety and efficacy of downsizing strategy with the Standard Annulus Sizing Strategy in TAVR for patients with type 0 bicuspid AS. TRIAL DESIGN: It is a prospective, multi-center, superiority, single-blinded, randomized controlled trial comparing the Down Sizing and Standard Annulus Sizing Strategy in patients with type 0 bicuspid aortic stenosis undergoing transcatheter aortic valve replacement. Eligible participants will include patients with severe type 0 bicuspid AS, as defined by criteria such as mean gradient across aortic valve ≥40 mmHg, peak aortic jet velocity ≥4.0 m/s, aortic valve area (AVA) ≤1.0 cm², or AVA index ≤0.6 cm2/m2. These patients will be randomly assigned, in a 1:1 ratio, to either the Down Sizing Strategy group or the Standard Sizing Strategy group. In the Down Sizing Strategy group, a valve one size smaller will be implanted if the "waist sign" manifests along with less than mild regurgitation during balloon pre-dilatation. The primary end point of the study is a composite of VARC-3 defined device success, absence of both permanent pacemaker implantation due to high-degree atrioventricular block and new-onset complete left bundle branch block. CONCLUSION: This study will compare the safety and efficacy of Down Sizing Strategy with the Standard Annulus Sizing Strategy and provide valuable insights into the optimal approach for sizing in TAVR patients with type 0 bicuspid AS. We hypothesize that the Down Sizing Strategy will demonstrate superiority when compared to the Standard Annulus Sizing Strategy. (Down Sizing Strategy (HANGZHOU Solution) vs Standard Sizing Strategy TAVR in Bicuspid Aortic Stenosis (Type 0) (TAILOR-TAVR), NCT05511792).


Assuntos
Estenose da Valva Aórtica , Doença da Válvula Aórtica Bicúspide , Próteses Valvulares Cardíacas , Desenho de Prótese , Substituição da Valva Aórtica Transcateter , Humanos , Substituição da Valva Aórtica Transcateter/métodos , Estenose da Valva Aórtica/cirurgia , Doença da Válvula Aórtica Bicúspide/cirurgia , Doença da Válvula Aórtica Bicúspide/complicações , Estudos Prospectivos , Método Simples-Cego , Valva Aórtica/cirurgia , Valva Aórtica/anormalidades , Valva Aórtica/diagnóstico por imagem , Masculino , Feminino
5.
Inorg Chem ; 63(1): 812-823, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38109652

RESUMO

Phosphors used in NIR spectroscopy require broadband emission, high external quantum yield, good ability, as well as a tunable spectral range to meet the detection criteria. Two-dimensional copper silicates MCuSi4O10 (M = Ca, Sr, Ba) play an important part in ancient art and technology as synthetic blue pigments. In the recent years, these compounds were reported to show a broad near-infrared emission when excited in the visible region. Inspired by the tunable structure of MCuSi4O10, a series of broadband phosphors Ca1-xSrxCuSi4O10 were designed for realizing continuously tunable NIR emission by a modulated Cu2+ crystal field environment. The emission maximum exhibits a red shift from 915 to 950 nm and the integral intensity enhances as the Sr2+ content varies in the range of 0-0.50, which is led by the lattice expansion and the following weakened crystal field splitting on tetrahedral-coordinated Cu2+. Compared to CaCuSi4O10, the optimized sample Ca0.5Sr0.5CuSi4O10 shows enhanced NIR emission by about 2.0-fold. It exhibits quite a high external quantum efficiency covering the NIR-I and -II regions (λmax = 950 nm, fwhm = 135 nm, EQE = 26.3%) with a strong absorption efficiency (74.7%) and a long excited-state lifetime (134 µs). These solid-solution phosphors (x = 0.0-0.5) show excellent thermal stability and maintain over 50% of the RT intensity at 200 °C. The optimized phosphor was encapsulated with red-light chips to fabricate NIR pc-LED and put into night-vision application. These good properties make these Cu2+-activated NIR phosphors appealing for multiple applications such as nondestructive testing, night version, lasers, and luminescent solar concentrators.

6.
Mycoses ; 67(1): e13688, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38214337

RESUMO

BACKGROUND: Pneumocystis jirovecii pneumonia (PJP) is a common and troublesome complication of kidney transplantation. In the era of prophylaxis, the peak incidence of PJP after kidney transplantation and specific characteristics of late-onset PJP have always been debated. METHODS: We performed a retrospective study by analysing the data of post-transplantation pneumonia in adult kidney transplantation recipients between March 2014 and December 2021 in The Affiliated First Hospital of University of Science and Technology of China (USTC). A total of 361 patients were included and divided into early-onset PJP, late-onset PJP and non-PJP groups. The characteristics of each group and related risk factors for the late-onset patients were investigated. RESULTS: Some patients developed PJP 9 months later with a second higher occurrence between month 10 and 15 after transplantation. Compared with non-PJP, ABO-incompatible and cytomegalovirus (CMV) viremia were significantly associated with late onset of PJP in multivariate analysis. The use of tacrolimus, CMV viremia, elevated CD8(+) T cell percent and hypoalbuminemia were risk factors for late PJP. Receiver operating characteristic curve analysis demonstrated that a combination of those factors could increase the sensitivity of prediction remarkably, with an area under the curve of 0.82, a sensitivity of 80% and a specificity of 83%. CONCLUSIONS: PJP could occur months after kidney transplantation. ABO-incompatible transplant recipients are at high risk of PJP. In the later stages of transplantation, CMV viremia, T lymphocyte subsets percentage and serum albumin levels should be monitored in patients using tacrolimus.


Assuntos
Infecções por Citomegalovirus , Transplante de Rim , Pneumocystis carinii , Pneumonia por Pneumocystis , Adulto , Humanos , Pneumonia por Pneumocystis/tratamento farmacológico , Transplante de Rim/efeitos adversos , Estudos Retrospectivos , Transplantados , Tacrolimo/uso terapêutico , Viremia/complicações , Fatores de Risco , Infecções por Citomegalovirus/complicações
7.
J Am Chem Soc ; 145(14): 7941-7951, 2023 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-36987634

RESUMO

Tumor-associated macrophages, especially M2-like macrophages, are extensively involved in tumor growth and metastasis, suppressing the innate immunity to help tumor cells escape and reshaping the microenvironment to help metastatic cells grow. However, in vivo, real-time visualized migration of M2-like macrophages has never been explored to monitor the tumor metastasis process. Herein, we prepared an M2-like macrophage-targeting nitric oxide (NO)-responsive nanoprobe (NRP@M-PHCQ) consisting of an amphiphilic block copolymer with mannose and hydroxychloroquine (HCQ) moieties (denoted as M-PHCQ) and a NO-responsive NIR-II probe (denoted as NRP). The mannose moieties provided M2-like macrophage-targeting capacity, and the HCQ moieties polarized M2-like macrophages to M1-like ones with enhanced NO secretion. Consequently, NRP@M-PHCQ was lit up by the secreted NO to visualize the migration and polarization of M2-like macrophages in real time. In vivo metastasis imaging with NRP@M-PHCQ successfully tracked early tumor metastasis in the lymph nodes and the lungs with high sensitivity, even superior to Luci-labeled bioluminescence imaging, suggesting the extensive distribution and critical role of M2-like macrophages in tumor metastasis. In general, this work provided a new strategy to sensitively image metastatic tumors by tracking the polarization of M2-like macrophages and visually disclosed the critical role of M2-like macrophages in early tumor metastasis.


Assuntos
Macrófagos , Manose , Linhagem Celular Tumoral
8.
Anal Chem ; 95(10): 4703-4711, 2023 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-36856710

RESUMO

Nanozymes are nanomaterials with enzyme-mimetic activity. It is known that DNA can interact with various nanozymes in different ways, enhancing or inhibiting the activity of nanozymes, which can be used to develop various biosensors. In this work, we synthesized a photosensitive covalent-organic framework (Tph-BT) as a nanozyme, and its oxidase and peroxidase activities could be reversely regulated by surface modification of single-stranded DNA (ssDNA) for the colorimetric detection of UO22+. Tph-BT exhibits excellent oxidase activity and weak peroxidase activity, and it is surprising to find that the UO22+-specific DNA aptamer can significantly inhibit the oxidase activity while greatly enhancing the peroxidase activity. The present UO22+ interacts with the DNA aptamer to form secondary structures and detaches from the surface of Tph-BT, thereby restoring the enzymatic activity of Tph-BT. Based on the reversed regulation effects of the DNA aptamer on the two types of enzymatic activities of Tph-BT, a novel "off-on" and "on-off" sensing platform can be constructed for the colorimetric analysis of UO22+. This research demonstrates that ssDNA can effectively regulate the different types of enzymatic activities of single COFs and achieve the sensitive and selective colorimetric analysis of radionuclides by the naked eye.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , DNA Catalítico , Estruturas Metalorgânicas , Urânio , DNA Catalítico/química , Urânio/análise , Aptâmeros de Nucleotídeos/química , Colorimetria , Estruturas Metalorgânicas/química , Oxirredutases , DNA de Cadeia Simples , Peroxidases
9.
Small ; 19(27): e2207798, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37012604

RESUMO

Nanomaterials with enzyme mimetic activity have attracted extensive attention, especially in the regulation of their catalytic activities by biomolecules or other polymers. Here, a covalent organic framework (Tph-BT COF) with excellent photocatalytic activity is constructed by Schiff base reaction, and its mimetic oxidase activity and peroxidase activity is inversely regulated via single-stranded DNA (ssDNA). Under light-emitting diode (LED) light irradiation, Tph-BT exhibited outstanding oxidase activity, which efficiently catalyzed oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) to produce blue oxTMB, and ssDNA, especially those with poly-thymidine (T) sequences, can significantly inhibit its oxidase activity. On the contrary, Tph-BT showed weak peroxidase activity, and the presence of ssDNA, particularly poly-cytosine (C) sequences, can remarkably enhance the peroxidase activity. The influence of base type, base length, and other factors on the activities of two enzymes is also studied, and the results reveal that the adsorption of ssDNA on the surface of Tph-BT prevented intersystem crossing (ISC) and energy transfer processes to reduce 1 O2 generation, while the electrostatic interaction between ssDNA and TMB enhanced Tph-BT's affinity for TMB to facilitate the electron transfer from TMB to • OH. This study investigates multitype mimetic enzyme activities of nonmetallic D-A conjugated COFs and demonstrates their feasibility of regulation by ssDNA.


Assuntos
Estruturas Metalorgânicas , Oxirredutases , DNA de Cadeia Simples , Antioxidantes , Peroxidases , Peroxidase/metabolismo , Colorimetria/métodos
10.
J Transl Med ; 21(1): 40, 2023 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-36681849

RESUMO

BACKGROUND: Current diagnosis tools for prostate cancer (PCa) such as serum PSA detection and prostate biopsy cannot distinguish dormant tumors from invasive malignancies, either be used as prognosis marker for castration resistant prostate cancer (CRPC), the lethal stage of PCa patients. Exosomes have been widely investigated as promising biomarkers for various diseases. We aim to characterize the proteomic and metabolomic profile of exosomes and to evaluate their potential value for the diagnosis of PCa, especially CRPC. We also investigate the functions of some specific exosome biomarkers in the progression of CRPC. METHODS: Integrated proteomics and metabolomics analysis were performed for plasma-derived exosomes collected from tumor-free controls (TFC), PCa and CRPC patients. Expression of specific exosomal proteins were further validated by targeted 4D-parallel reaction monitoring (PRM) mass spectrometry among the three cohorts. Tissue distribution and functional role of exosomal protein LRG1 was studied in clinical PCa tissue samples and cell line models. RESULTS: Three potential exosomal protein markers were identified. The apolipoprotein E level in PCa samples was 1.7-fold higher than that in TFC (receiver operating characteristic value, 0.74). Similarly, the levels of exosome-derived leucine-rich alpha2-glycoprotein 1 (LRG1) and inter-alpha-trypsin inhibitor heavy chain H3 (ITIH3) in the CRPC group were 1.7 and 2.04 times, respectively, higher than those in the PCa group (ROC values, 0.84 and 0.85, respectively), indicating that LRG1 and ITIH3 could serve as predictive markers for CRPC. For metabolomic evaluation of exosomes, a series of differentially expressed metabolites were identified, and a combined metabolite panel showed ROC value of 0.94 for distinguishing PCa from TFC and 0.97 for distinguishing CRPC from PCa. Immunohistochemistry of tissue microarray showed that LRG1 protein was significantly upregulated in advanced prostate cancer and functional assay revealed that ectopic expression of LRG1 can significantly enhance the malignant phenotype of prostate cancer cells. More importantly, PCa cell derived LRG1-overexpressed exosomes remarkably promoted angiogenesis. CONCLUSION: Integration of proteomics and metabolomics data generated proteomic and metabolic signatures of plasma exosomes that may facilitate discrimination of CRPC from PCa and TFC patients, suggesting the potential of exosomal proteins and metabolites as CRPC markers. The study also confirmed the important role of exosomal protein LRG1 in PCa malignant progression.


Assuntos
Exossomos , Neoplasias de Próstata Resistentes à Castração , Humanos , Masculino , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/metabolismo , Neoplasias de Próstata Resistentes à Castração/patologia , Proteômica , Próstata/metabolismo , Exossomos/metabolismo
11.
Strahlenther Onkol ; 199(4): 360-369, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36063205

RESUMO

PURPOSE: In Germany, the new Licensing Regulations for Physicians 2025 (Ärztliche Approbationsordnung, ÄApprO) define a binding legal framework on the basis of which medical faculties modernize their curricula. Since 2015, the National Competence Based Learning Objectives Catalogue for Medicine 2.0 (Nationaler Kompetenzbasierter Lernzielkatalog 2.0., NKLM) formulates competencies and learning objectives to be achieved in the course of studies as curriculum orientation for the medical faculties. In addition, about 80% of the areas of a new core curriculum are to be made compulsory. A needs analysis in the target group of students has not yet taken place for the subject of radiation therapy (RT) or radiation oncology (RO). This study therefore surveys the experiences and requirements of students regarding medical education in RT. METHODS: Qualitative single-center study using a semistructured in-depth focus group with 11 medical students (20-26 years; 6 female, 5 male) was conducted. Brainstorming sessions were conducted in small groups and individually; oral contributions were recorded, transcribed, and analyzed using qualitative content analysis according to Mayring. Results were compared with the content of the future curriculum and reviewed for congruence with current expert recommendations of the German Society of Radiation Oncology (Deutsche Gesellschaft für Radioonkologie, DEGRO). RESULTS: The plans to develop a longitudinal and practice-oriented curriculum was positively received by students. Specifically, students wanted to introduce the basics of RT as an early link to practice in preclinical teaching units. The necessary acquisition of communicative skills should also be taught by lecturers in RO. Methodologically, regular digital survey tools for self-monitoring, discussion rooms, and problem-based learning were named. In the perception of students, the subject appears underrepresented in relation to its relevance in the multimodal therapy of oncological diseases. CONCLUSION: Results of the needs analysis for the subject of RT are consistent with ÄApprO, NKLM, and DEGRO. Moreover, they complement them and should be considered in the curriculum development of Masterplan Medical Education 2020 (Masterplan Medizinstudium 2020). The results contribute to high-quality and target-group-oriented medical training in the subject of RT, increased visibility, and thus early bonding of future physicians to RO in Germany.


Assuntos
Radioterapia (Especialidade) , Estudantes de Medicina , Masculino , Feminino , Humanos , Grupos Focais , Currículo , Docentes de Medicina , Alemanha , Competência Clínica
12.
Inorg Chem ; 62(33): 13370-13377, 2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37560992

RESUMO

As far as we are concerned, the phenomenon of Ni2+ luminescence in tetrahedral coordination has not been reported. For the first time, a new NIR phosphor Ca2GeO4:Ni2+ is developed in this work. It is found that the NIR emission from this phosphor is a sharp peak attributed to the unusual Ni2+-occupied GeO4 site in the lattice, instead of the conventional broadband luminescence of Ni2+ in the octahedrally coordinated site. Crystal-field analysis has been applied, and the parameters Dq, B, and Δ are calculated to reveal the relationship between the emission profile and the crystal field strength. The optimal Ni2+ doping concentration is found to be 1%. Ca2GeO4:Ni2+ provides an efficient sharp-line (fwhm = 16 nm) emission centered at 1164 nm which originates from the 1T2 → 3T1 transition with an internal quantum efficiency of 23.1% and a decay lifetime of about 300 µs. This work could provide some new insights to explore novel NIR luminescent materials based on transition-metal elements.

13.
Inorg Chem ; 62(35): 14494-14503, 2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37611183

RESUMO

Realizing ultra-wideband and tunable near-infrared (NIR) emission remains a great challenge in NIR phosphor development. The luminescence of most reported NIR phosphors exhibits a peak wavelength shorter than 1000 nm and the corresponding FWHM is <200 nm. Here, a series of Cr3+-activated Li(Sc,In)(Si,Ge)O4 phosphors with ultra-wideband and tunable NIR-II emission are successfully developed based on the host composition engineering strategy. Significant spectral engineering in the NIR-II region is achieved with a peak wavelength changing from 1110 to 1253 nm. The olivine host structure could provide Cr3+ activator a highly distorted octahedral site with very weak crystal field strength, which results in NIR-II ultra-wideband emission with FWHM > 300 nm. A detailed discussion on the relationship between structural variation, crystal field splitting, and NIR luminescence has been applied. As far as we know, it is the first report about Cr3+ NIR luminescence engineering in such a long wavelength and wide range. The application of these NIR-II phosphors is demonstrated in intensity-based luminescent thermometry with a relative sensitivity of >2.0% K-1 in the physiological temperature range.

14.
Herz ; 48(5): 393-398, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36720725

RESUMO

OBJECTIVE: Our aim was to determine the risk factors of postoperative systemic inflammatory response syndrome (SIRS) in patients with transcatheter aortic valve replacement (TAVR), identify those with a high risk of SIRS, and help reduce SIRS occurrence. METHODS: A retrospective cohort study was conducted to collect the clinical data of patients who underwent TAVR from January 2014 to December 2019 at a tertiary hospital in Zhejiang Province. The study included 156 men and 94 women. Patients were divided into SIRS and non-SIRS groups. The pre-, intra-, and postoperative indices of the two groups were recorded. The data of the two groups were compared, and univariate analysis was performed. All statistically significant factors were assessed using binary logistic regression analysis to clarify the risk factors of SIRS after TAVR. RESULTS: Overall, 30 patients developed SIRS after TAVR, with an incidence rate of 12%, an odds ratio (OR) of 0.571, and a 95% confidence interval (CI) of 0.469-0.694 (p = 0.000). There was a significant correlation between SIRS and glucose (OR: 0.823, 95% CI: 0.678-1.000, p = 0.049), albumin (OR: 0.938, 95% CI: 0.881-0.998, p = 0.044), brain natriuretic peptide (OR: 1.000, 95% CI: 1.000-1.000, p = 0.010), sex (OR: 0.412, 95% CI: 0.190-0.892, p = 0.025), and history of hypertension (OR: 0.375, 95% CI: 0.169-0.819, p = 0.014). Multivariate regression analysis demonstrated that age (OR: 1.190, 95%CI: 1.073-1.319, p = 0.001) and body mass index (BMI; OR: 0.559, 95% CI: 0.447-0.698, p = 0.000) were independent risk factors for postoperative SIRS in patients with TAVR. CONCLUSION: The incidence of SIRS after TAVR was 12%. There was a significant correlation between SIRS and albumin, glucose, and hypertension. The independent risk factors for SIRS after TAVR were age and BMI.


Assuntos
Estenose da Valva Aórtica , Implante de Prótese de Valva Cardíaca , Substituição da Valva Aórtica Transcateter , Masculino , Humanos , Feminino , Substituição da Valva Aórtica Transcateter/efeitos adversos , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/cirurgia , Implante de Prótese de Valva Cardíaca/efeitos adversos , Estudos Retrospectivos , Resultado do Tratamento , Fatores de Risco , Síndrome de Resposta Inflamatória Sistêmica/epidemiologia , Síndrome de Resposta Inflamatória Sistêmica/etiologia , Glucose , Albuminas
15.
Sensors (Basel) ; 23(11)2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37299960

RESUMO

Automatic Modulation Recognition (AMR) can obtain the modulation mode of the received signal for subsequent processing without the assistance of the transmitter. Although the existing AMR methods have been mature for the orthogonal signals, these methods face challenges when deployed in non-orthogonal transmission systems due to the superimposed signals. In this paper, we aim to develop efficient AMR methods for both downlink and uplink non-orthogonal transmission signals using deep learning-based data-driven classification methodology. Specifically, for downlink non-orthogonal signals, we propose a Bi-directional Long Short-Term Memory (BiLSTM)-based AMR method that exploits long-term data dependence to automatically learn irregular signal constellation shapes. Transfer learning is further incorporated to improve recognition accuracy and robustness under varying transmission conditions. For uplink non-orthogonal signals, the combinatorial number of classification types explodes exponentially with the number of signal layers, which becomes the major obstacle to AMR. We develop a spatio-temporal fusion network based on the attention mechanism to efficiently extract spatio-temporal features, and network details are optimized according to the superposition characteristics of non-orthogonal signals. Experiments show that the proposed deep learning-based methods outperform their conventional counterparts in both downlink and uplink non-orthogonal systems. In a typical uplink scenario with three non-orthogonal signal layers, the recognition accuracy can approach 96.6% in the Gaussian channel, which is 19% higher than the vanilla Convolution Neural Network.


Assuntos
Aprendizado Profundo , Memória de Longo Prazo , Redes Neurais de Computação , Distribuição Normal , Reconhecimento Psicológico
16.
Nano Lett ; 22(1): 476-484, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-34978815

RESUMO

A charge density wave (CDW) is a collective quantum phenomenon in metals and features a wavelike modulation of the conduction electron density. A microscopic understanding and experimental control of this many-body electronic state in atomically thin materials remain hot topics in materials physics. By means of material engineering, we realized a dimensionality and Zr intercalation induced semiconductor-metal phase transition in 1T-ZrX2 (X = Se, Te) ultrathin films, accompanied by a commensurate 2 × 2 CDW order. Furthermore, we observed a CDW energy gap of up to 22 meV around the Fermi level. Fourier-transformed scanning tunneling microscopy and angle-resolved photoemission spectroscopy reveal that 1T-ZrX2 films exhibit the simplest Fermi surface among the known CDW materials in TMDCs, consisting only of a Zr 4d derived elliptical electron conduction band at the corners of the Brillouin zone.

17.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 40(9): 1093-1099, 2023 Sep 10.
Artigo em Zh | MEDLINE | ID: mdl-37643954

RESUMO

OBJECTIVE: To summarize the clinical features and spectrum of genetic variants in 12 patients with Loeys-Dietz syndrome (LDS), and to explore the correlation between the type of genetic variants and clinical phenotypes. METHODS: Twelve patients suspected for LDS at Beijing Anzhen Hospital Affiliated to Capital Medical University from January 2015 to January 2022 were selected as the study subjects. Clinical data of the patients were collected. Genomic DNA was extracted from peripheral blood samples and subjected to genetic testing. Pathogenicity of candidate variants was analyzed. RESULTS: The clinical phenotypes of the 12 patients have mainly included cardiovascular, musculoskeletal, craniofacial, skin, ocular and other systemic signs. Four patients (patients 5-1, 5-2, 6, 7) have carried heterozygous missense variants of the TGFBR1 gene, 5 patients (patients 1-1, 1-2, 2, 3, 4) have carried heterozygous variants of the TGFBR2 gene, and 2 patients (patients 8-1, 8-2) had carried heterozygous frameshift variants of the TGFB3 gene. One patient (patient 9) had carried a heterozygous missense variant of the SMAD3 gene. Among these, TGFBR1 c.603T>G (p.1201M) and TGFB3 c.536delA (p.H179FS35) had not been reported previously. CONCLUSION: Variants of the TGFBR1, TGFBR2, SMAD3, TGFB2, TGFB3 and SMAD2 genes are mainly associated with LDS. The severity of the disease phenotype caused by the same variant may vary, whilst the clinical phenotype caused by different variant sites may be specific.


Assuntos
Síndrome de Loeys-Dietz , Humanos , Síndrome de Loeys-Dietz/genética , Receptor do Fator de Crescimento Transformador beta Tipo I/genética , Receptor do Fator de Crescimento Transformador beta Tipo II/genética , Fator de Crescimento Transformador beta3 , Face
18.
Small ; 18(13): e2106547, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35112794

RESUMO

The capture of circulating tumor cells (CTCs) by nanostructured substrate surface is a useful method for early diagnosis of cancer. At present, most methods used to improve the cell capture efficiency are based on changing substrate surface properties. However, there are still some gaps between these methods and practical applications. Here, a method is presented for improving cell capture efficiency from a different perspective, that is, changing the properties of the cells. Concretely, the mechanical properties of the cell membrane are changed by adding Cytochalasin D to soften the cell membrane. Furthermore, a corresponding theoretical model is proposed to explain the experimental results. It is found that cell softening can reduce the resistance of cell adhesion, which makes the adhesion ability stronger. The high-efficiency capture of cells by softening the cell membrane provides a potential method to improve the detection performance of CTCs.


Assuntos
Nanoestruturas , Células Neoplásicas Circulantes , Linhagem Celular Tumoral , Membrana Celular/metabolismo , Separação Celular/métodos , Molécula de Adesão da Célula Epitelial/metabolismo , Humanos , Nanoestruturas/química , Células Neoplásicas Circulantes/patologia
19.
Chemistry ; 28(59): e202201783, 2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-35851966

RESUMO

The non-petroleum synthesis route of ethanol from syngas (H2 +CO) with methyl acetate (MA) as the core intermediate product has been confirmed as an excellent industrialization route for high purity ethanol production. However, as the central part of this tandem-catalysis path, the carbonylation of dimethyl ether (DME) to MA is limited by the undesirable catalytic activity and stability of zeolite catalysts. Herein, a facile inhibitor-assisted strategy was developed for constructing self-assembled nano-Mordenite (nano-MOR) zeolites without using any expensive or complex template. A nano-filamentous MOR zeolite with only 70 nm crystal diameter was successfully synthesized by selectively controlling the crystal growth orientation with a specific inhibitor. The catalytic performance of self-assembled nano-MOR catalysts was remarkably outstanding in DME carbonylation reaction. The highest Space-Time Yield (STY) of MA was achieved over Nanofilament MOR (NF-MOR), which was significantly improved comparing with that of the traditional Ellipsoid-MOR (ES-MOR) [3780 mmol/(kg ⋅ h) vs. 1368 mmol/(kg ⋅ h)]. One-step ethanol synthesis was realized by combining the MOR catalyst and an innovative self-reduced Cu-ZnO/SiO2 (CZ/SiO2 ) catalyst in a rationally designed dual-bed catalysis system. Adopting the tailor-made NF-MOR&CZ/SiO2 combination, it obtained the highest STY of ethanol, about 4 times of the conventional ES-MOR&CZ combination [1800 mmol/(kg ⋅ h) vs. 476 mmol/(kg ⋅ h)]. The present self-assembled nano-MOR zeolites synthetic strategy opens a new way for the fabrication of high-performance zeolites for practical industrial applications in catalytic conversions of one-carbon (C1) small molecules to high value-added chemicals.

20.
Catheter Cardiovasc Interv ; 99 Suppl 1: 1432-1439, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35094487

RESUMO

OBJECTIVES: To evaluate the feasibility of self-expanding transcatheter aortic valve replacement (TAVR) in patients with aortic stenosis and extremely horizontal aortas (aortic angulation ≥70°). BACKGROUND: As TAVR using a self-expanding prosthesis is an off-label treatment for patients with extremely horizontal aortas, these patients are often excluded from randomized controlled trials involving self-expanding TAVR. METHODS: This study enrolled 27 consecutive patients with extremely horizontal aortas who underwent self-expanding TAVR for severe aortic stenosis. RESULTS: The patients' average age was 76.4 years, with a median Society of Thoracic Surgeons score of 4.53%. The device success and 30-day mortality rates were 66.7% and 7.4%, respectively. The sinotubular junction (STJ) was significantly smaller in the device success group (p = 0.001). The receiver operating characteristic curve analysis found that the area under the curve was 0.907 (95% confidence interval: 0.790-1.000, p = 0.001), validating the association between STJ diameter and device success. An optimal cutoff of 33.6 mm was determined using the Youden index, with a sensitivity and specificity of 88.9% and 77.8%, respectively. The device success rate was significantly higher (93.3% vs. 33.3%, p = 0.003) in patients with STJ diameters ≤33.6 mm (n = 15). In the subgroup analyses, severe valve calcification (n = 9) was associated with a higher incidence of moderate or severe paravalvular leakage (44.0% vs. 0%, p = 0.008), while a higher rate of second valve implantation (60.0% vs. 9.1%, p = 0.030) was found in patients with less than moderate valve calcification (n = 5). CONCLUSION: Self-expanding TAVR could be suitable for patients with extremely horizontal aortas after careful preoperative evaluation.


Assuntos
Estenose da Valva Aórtica , Próteses Valvulares Cardíacas , Substituição da Valva Aórtica Transcateter , Idoso , Aorta/cirurgia , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Humanos , Desenho de Prótese , Fatores de Risco , Resultado do Tratamento
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