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1.
J Org Chem ; 89(3): 1692-1702, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38207341

RESUMO

The products containing pyrimidine scaffolds exhibit various important physiological and biological activities. To date, the strategies to generate 4,5,6-trisubstituted pyrimidines were not reported. Here, a copper-catalyzed reaction of 2H-azirines with α-isocyanoacetates or α-isocyanoacetamides has been developed, rapidly preparing 4,5,6-trisubstituted pyrimidines. The mechanistic results reveal that this strategy underwent a formal 1, 3-dipolar [3 + 2] cycloaddition/ring-expanding/oxidative aromatization procedure to construct the desired pyrimidines.

2.
J Org Chem ; 89(8): 5423-5433, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38557074

RESUMO

Currently, most conventional methods to achieve imidazo[1,5-a]pyridines have limitations for the synthesis of 3-acyl imidazo[1,5-a]pyridines. Herein, a novel and efficient Cu(I)-catalyzed three-component annulation method for the synthesis of valuable 3-acyl imidazo[1,5-a]pyridines by the reaction of 2-pyridinyl-substituted p-QMs, terminal alkynes, and TsN3 in the presence of O2 under mild conditions have successfully been developed. The investigation indicated that molecular oxygen (O2) and TsN3, respectively, serving as oxygen and nitrogen sources, were essential for the successful completion of the reaction system.

3.
Photochem Photobiol Sci ; 23(6): 1031-1039, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38839721

RESUMO

A novel cyclic chalcone fluorescent probe C-PN was synthesized to detect ONOO-. After reaction with peroxynitrite, the double bond of C-PN in the cyclic chalcone structure was disconnected, which caused the change of intramolecular charge transfer (ICT) effect, emitting blue fluorescence and quenching orange red fluorescence. Visible to the naked eye, the color of the probe solution changed. The probe showed low sensitivity (detection limit = 20.2 nm), short response time (less than 60 s) at low concentration of ONOO-, good visibility, and good selectivity and stability for ONOO-.

4.
J Musculoskelet Neuronal Interact ; 24(1): 82-89, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38427372

RESUMO

OBJECTIVE: To investigate the therapeutic effects of autologous platelet-rich plasma (PRP) combined with sodium hyaluronate on tendon healing following rotator cuff injury repair in rabbits. METHODS: New Zealand white rabbits were randomly assigned to five groups: sham operation group, control group, PRP group, sodium hyaluronate group, and combined group, each comprising 12 rabbits. A rotator cuff injury model was established in all groups except the sham operation group. At 8 weeks post-surgery, 12 lateral rotator cuff specimens were taken from each group. Four specimens were randomly selected from each group for biomechanical testing, and analyses were conducted on the expression of vascular endothelial growth factor (VEGF), the fiber area ratio of COL-I and COL-III, and tissue morphology. RESULTS: The combined group exhibited the highest biomechanical strength in the cuff tissue of white rabbits (P < 0.05). There was no significant difference in VEGF levels among the five groups (F = 0.814, P = 0.523). However, a significant difference was observed in the ratio of fiber area between COL-I and COL-III groups (F = 11.600, P < 0.001), with the combined group scoring the highest (3.82 ± 0.47 minutes). The inflammatory infiltration in tendon-bone tissue was minimal, and histological morphology was optimal. CONCLUSION: The combination of PRP and sodium hyaluronate effectively promotes the repair of rotator cuff injuries and accelerates tendon-bone healing.


Assuntos
Plasma Rico em Plaquetas , Lesões do Manguito Rotador , Coelhos , Animais , Lesões do Manguito Rotador/terapia , Lesões do Manguito Rotador/metabolismo , Lesões do Manguito Rotador/patologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Ácido Hialurônico/farmacologia , Ácido Hialurônico/metabolismo , Cicatrização , Modelos Animais de Doenças , Tendões , Plasma Rico em Plaquetas/metabolismo , Fenômenos Biomecânicos
5.
Allergy Asthma Proc ; 45(3): 173-179, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38755782

RESUMO

Background: Allergic rhinitis (AR) is traditionally subdivided into seasonal AR (SAR) and perennial AR (PAR) according to the type of allergen and the occurrence of symptoms during the year. There are currently no reports on the comparison of trait profiles for SAR and PAR during the allergen exposure. Purpose: The purpose of this study was to analyze the clinical characteristics of SAR and PAR during respective allergen exposure periods to provide valuable information for the development of treatment strategies. Methods: This study was performed between August 1, 2021, and January 31, 2022, in the Department of Allergy, Beijing Tongren Hospital. We continuously included diagnosed SAR and PAR outpatients who volunteered to participate in the survey. A questionnaire with regard to medical history, severity of symptoms, and diagnosis and treatment status was collected. Results: A total of 296 patients with SAR and 448 with PAR were finally recruited. Patients with SAR had more severe rhinorrhea compared with patients with PAR (p < 0.001), whereas there was no statistically significant difference in the severity of itching, sneezing, and congestion between the two entities (p ≥ 0.05). Both the gritty and watery eyes of patients with SAR were noticeably more severe than those of patients with PAR (PTotal Ocular Symptom Score [PTOSS] < 0.001). AR symptom severity is mainly associated with the comorbid allergic conjunctivitis (odds ratio 1.94 [95% confidence interval, 1.21-3.09]). SAR patients and PAR patients show no statistically significant differences in terms of their frequency of visits, annual expenditure, and choice of medication treatment for AR (p > 0.05). The overall control under standard medication of both patients with PAR and those with SAR is not ideal, especially in SAR. Conclusion: The current cross-sectional study demonstrated that the patients with SAR exhibited more severe overall clinical symptoms than those with PAR, especially nasal rhinorrhea and gritty and watery eyes. Both of the two disease entities have poor control under standardized medication treatment, especially in SAR. Further multicenter longitudinal studies that involve larger and more diverse populations should be conducted to provide a more accurate and comprehensive understanding of the condition.


Assuntos
Alérgenos , Rinite Alérgica Perene , Rinite Alérgica Sazonal , Humanos , Masculino , Feminino , Adulto , Alérgenos/imunologia , Rinite Alérgica Sazonal/epidemiologia , Rinite Alérgica Sazonal/diagnóstico , Pessoa de Meia-Idade , Rinite Alérgica Perene/epidemiologia , Rinite Alérgica Perene/diagnóstico , Índice de Gravidade de Doença , Adulto Jovem , Adolescente , Inquéritos e Questionários
6.
J Environ Sci (China) ; 138: 189-199, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38135387

RESUMO

Membrane distillation (MD) is a promising alternative desalination technology, but the hydrophobic membrane cannot intercept volatile organic compounds (VOCs), resulting in aggravation in the quality of permeate. In term of this, electro-Fenton (EF) was coupled with sweeping gas membrane distillation (SGMD) in a more efficient way to construct an advanced oxidation barrier at the gas-liquid interface, so that the VOCs could be trapped in this layer to guarantee the water quality of the distillate. During the so-called EF-MD process, an interfacial interception barrier containing hydroxyl radical formed on the hydrophobic membrane surface. It contributed to the high phenol rejection of 90.2% with the permeate phenol concentration lower than 1.50 mg/L. Effective interceptions can be achieved in a wide temperature range, even though the permeate flux of phenol was also intensified. The EF-MD system was robust to high salinity and could electrochemically regenerate ferrous ions, which endowed the long-term stability of the system. This novel EF-MD configuration proposed a valuable strategy to intercept VOCs in MD and will broaden the application of MD in hypersaline wastewater treatment.


Assuntos
Compostos Orgânicos Voláteis , Purificação da Água , Destilação/métodos , Membranas Artificiais , Purificação da Água/métodos , Fenóis
7.
BMC Cancer ; 23(1): 101, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36717809

RESUMO

BACKGROUND: Systemic inflammation is crucial for the development and progression of cancers. The advanced lung cancer inflammation index (ALI) is considered to be a better indicator of systemic inflammation than current biomarkers. However, the prognostic value of the ALI in gastrointestinal neoplasms remains unclear. We performed the first meta-analysis to explore the association between ALI and gastrointestinal oncologic outcomes to help physicians better evaluate the prognosis of those patients. METHODS: Eligible articles were retrieved using PubMed, the Cochrane Library, EMBASE, and Google Scholar by December 29, 2022. Clinical outcomes were overall survival (OS), disease-free survival (DFS), progression-free survival (PFS), and cancer-specific survival (CSS). RESULTS: A total of 18 articles with 6898 patients were included in this meta-analysis. The pooled results demonstrated that a low ALI was correlated with poor OS (HR = 1.914, 95% CI: 1.514-2.419, P < 0.001), DFS (HR = 1.631, 95% CI: 1.197-2.224, P = 0.002), and PFS (HR = 1.679, 95% CI: 1.073-2.628, P = 0.023) of patients with gastrointestinal cancers. Subgroup analysis revealed that a low ALI was associated with shorter OS (HR = 2.279, 95% CI: 1.769-2.935, P < 0.001) and DFS (HR = 1.631, 95% CI: 1.197-2.224, P = 0.002), and PFS (HR = 1.911, 95% CI: 1.517-2.408, P = 0.002) of patients with colorectal cancer. However, the ALI was not related to CSS in the patients with gastrointestinal malignancy (HR = 1.121, 95% CI: 0.694-1.812, P = 0.640). Sensitivity analysis supported the stability and dependability of the above results. CONCLUSION: The pre-treatment ALI was a useful predictor of prognosis in patients with gastrointestinal cancers.


Assuntos
Neoplasias Gastrointestinais , Neoplasias Pulmonares , Humanos , Prognóstico , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/diagnóstico , Neoplasias Gastrointestinais/complicações , Neoplasias Gastrointestinais/diagnóstico , Biomarcadores , Inflamação
8.
J Org Chem ; 88(22): 15696-15707, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-37906125

RESUMO

Cyanoacrylates have a wide range of biological activities and are extensively applied in production and daily life. Classic synthetic routes to cyanoacrylates have many limitations. Herein, we demonstrate an elemental sulfur-promoted method for the synthesis of ß,ß-diaryl cyanoacrylates by a tandem 1,6-Michael addition/oxidation/elimination process from p-QMs and cyanoacetates under optimal conditions. The effective protocol has good substrate scopes and yields, and the ratio of inseparable E/Z isomers of cyanoacrylates is also determined by 1HNMR.

9.
Org Biomol Chem ; 21(35): 7151-7157, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37609782

RESUMO

Fuchsones have wide applications in modern society. Present methods for generating fuchsones have many disadvantages and there are significant limitations for further exploration of fuchsone applications. Herein, we describe a DMSO-promoted direct δ-selective arylation of p-QMs to synthesize symmetrical and unsymmetrical fuchsones under metal-free conditions by employing p-QMs themselves or substituted phenols as aryl sources. As unprecedented methods, these novel strategies present a great advantage and significance for further exploration of fuchsones and the development of new applications.

10.
Chem Soc Rev ; 51(2): 672-719, 2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-34932047

RESUMO

Tailored design of high-performance nanofiltration (NF) membranes is desirable because the requirements for membrane performance, particularly ion/salt rejection and selectivity, differ among the various applications of NF technology ranging from drinking water production to resource mining. However, this customization greatly relies on a comprehensive understanding of the influence of membrane fabrication methods and conditions on membrane properties and the relationships between the membrane structural and physicochemical properties and membrane performance. Since the inception of NF, much progress has been made in forming the foundation of tailored design of NF membranes and the underlying governing principles. This progress includes theories regarding NF mass transfer and solute rejection, further exploitation of the classical interfacial polymerization technique, and development of novel materials and membrane fabrication methods. In this critical review, we first summarize the progress made in controllable design of NF membrane properties in recent years from the perspective of optimizing interfacial polymerization techniques and adopting new manufacturing processes and materials. We then discuss the property-performance relationships based on solvent/solute mass transfer theories and mathematical models, and draw conclusions on membrane structural and physicochemical parameter regulation by modifying the fabrication process to improve membrane separation performance. Next, existing and potential applications of these NF membranes in water treatment processes are systematically discussed according to the different separation requirements. Finally, we point out the prospects and challenges of tailored design of NF membranes for water treatment applications. This review bridges the long-existing gaps between the pressing demand for suitable NF membranes from the industrial community and the surge of publications by the scientific community in recent years.


Assuntos
Membranas Artificiais , Purificação da Água , Polimerização
11.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 48(5): 682-690, 2023 May 28.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-37539570

RESUMO

OBJECTIVES: Primary trigeminal neuralgia (PTN) is a common cranial nerve disease in neurosurgery, which seriously endangers the physical and mental health of patients. Percutaneous balloon compression (PBC) has become an effective procedure for the treatment of PTN by blocking pain conduction through minimally invasive puncture. However, the recurrence of facial pain after PBC is still a major problem for PTN patients. Intraoperative balloon shape, pressure and compression time can affect the prognosis of patients with PBC after surgery. The foramen ovale size has an effect on the balloon pressure in Meckel's lumen. This study aims to analyse the predictive value of foramen ovale size for postoperative pain recurrence of PBC by exploring the relationship between foramen ovale size and postoperative pain recurrence of PBC. METHODS: A retrospectively analysis was conducted on the clinical data of 60 patients with PTN who were treated with PBC in Department of Neurosurgery, Affiliated Hospital of Chengde Medical College from November 2018 to December 2021. We followed-up and recorded the Barrow Neurological Institute (BNI) pain score at 1, 3, 6 and 12 months after operation. According to the BNI pain score at 12 months after surgery, the patients were divided into a cure group (BNI pain score I to Ⅱ) and a recurrence group (BNI pain score Ⅲ to Ⅴ). The long diameter, transverse diameter and area of foramen ovale on the affected side and the healthy side of the 2 groups were measured. Receiver operating characteristic (ROC) curve and area under the curve (AUC) were used for analysis the relationship between the recurrence of pain and the long diameter, transverse diameter, area of foramen ovale on the affected side, and aspect ratio, transverse diameter ratio, area ratio of foramen ovale on the affected side to healthy side in the 2 groups. RESULTS: At the end of 12 months of follow-up, 50 (83.3%) patients had pain relief (the cured group), 10 (16.7%) patients had different degrees of pain recurrence (the recurrence group), and the total effective rate was 83.3%. There were no significant differences in preoperative baseline data between the 2 groups (all P>0.05). The long diameter of foramen ovale on the affected side, the long diameter ratio and area ratio of foramen ovale on the affected/healthy side in the cured group were significantly higher than those in the recurrence group (all P<0.05), and there were no significant differences in the transverse diameter and area of foramen ovale on the affected side and the transverse diameter ratio of foramen ovale on the affected/healthy side between the 2 groups (all P>0.05). The ROC curve analysis showed that the AUC of the long diameter of foramen ovale on the affected side was 0.290 (95% CI 0.131 to 0.449, P=0.073), and the AUC of aspect ratio of foramen ovale on the affected side to healthy side was 0.792 (95% CI 0.628 to 0.956, P=0.004). The AUC of area ratio of foramen ovale on the affected side to healthy side was 0.766 (95% CI 0.591 to 0.941, P=0.008), indicating that aspect ratio and area ratio of foramen ovale on the affected side to healthy side had a good predictive effect on postoperative pain recurrence of PBC. When aspect ratio of foramen ovale on the affected side to healthy side was less than 0.886 3 or area ratio of foramen ovale on the affected side to healthy side was less than 0.869 4, postoperative pain recurrence was common. CONCLUSIONS: Accurate evaluation of the foramen ovale size of skull base before operation is of great significance in predicting pain recurrence after PBC.


Assuntos
Forame Oval , Neuralgia do Trigêmeo , Humanos , Estudos Retrospectivos , Resultado do Tratamento , Neuralgia do Trigêmeo/etiologia , Neuralgia do Trigêmeo/cirurgia , Dor Pós-Operatória/etiologia , Recidiva
12.
Phys Rev Lett ; 128(8): 083202, 2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-35275661

RESUMO

Optically trapped mixed-species single atom arrays with arbitrary geometry are an attractive and promising platform for various applications, because tunable quantum systems with multiple components provide extra degrees of freedom for experimental control. Here, we report the first demonstration of two-dimensional 6×4 dual-species atom assembly of ^{85}Rb (^{87}Rb) atoms with a filling fraction of 0.88 (0.89). This mixed-species atomic synthesis is achieved via rearranging initially randomly distributed atoms by a sorting algorithm (heuristic heteronuclear algorithm) which is designed for bottom-up atom assembly with both user-defined geometries and two-species atom number ratios. Our fully tunable hybrid-atom systems with scalable advantages are a good starting point for high-fidelity quantum logic, many-body quantum simulation, and single molecule array formation.

13.
Environ Sci Technol ; 56(15): 10954-10962, 2022 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-35819002

RESUMO

To enhance the use of nanofiltration in the production of quality drinking water, particularly through the efficient removal of micropollutants yet still preserving essential minerals, the targeted nanofiltration membranes (NFMs) are required to have small pore dimensions coupled with a high, net-negative charge density. Herein, after the formation of a separation layer using piperazine interfacially polymerized with trimesoyl chloride, the exploitation of residual amine groups was systematically investigated by different diacyl chlorides in an organic milieu, which caused the upper part of the final separation layer to be denser and highly negatively charged. Hence, this protocol offers a novel means to fabricate NFMs simultaneously endowed with a low molecular cutoff (MWCO) of 145-238 Da and a reduced rejection of MgCl2 (48%-80%) as well as a competitive water permeance. Those features are ideally applicable to the goal of removing small micropollutants while preserving mineral ions, as needed for the energy-efficient production of safe, quality drinking water. Furthermore, an attempt was made to correlate MWCO with MgCl2 rejection, which provides some insights on the nexus of the electrostatic effects constrained by size exclusion. The significance of residual amine groups and the modification environment was unveiled, and this method paves a new avenue for designing functional NFMs.


Assuntos
Água Potável , Nylons , Aminas , Cátions Bivalentes , Membranas Artificiais
14.
Environ Sci Technol ; 56(24): 17955-17964, 2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36446026

RESUMO

Nanofiltration (NF) is an effective technology for removing trace organic contaminants (TrOCs), while the inherent trade-off effect between water permeance and solute rejections hinders its widespread application in water treatment. Herein, we propose a novel scheme of "monomers with sacrificial groups" to regulate the microstructure of the polyamide active layer via introducing a hydrolyzable ester group onto piperazine to control the diffusion and interfacial polymerization process. The achieved benefits include narrowing the pore size, improving the interpore connectivity, enhancing the microporosity, and reducing the active layer thickness, which collectively realized the simultaneous improvement of water permeance and enhancement of TrOCs rejection performance. The resulting membranes were superior to both the control and commercial membranes, especially in water-TrOCs selectivity. The effects of using the new monomers on the membrane physicochemical properties were systematically studied, and underlying mechanisms for the enhanced separation performance were further revealed by simulating the polymerization process through density functional theory calculation and measuring the trans-interface diffusion rate of monomers. This study demonstrates a novel promising NF membrane synthesis strategy by designing the structure of reaction monomers for achieving excellent rejection of TrOCs with a low energy input in water treatment.

15.
Environ Sci Technol ; 56(22): 15220-15237, 2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-36330774

RESUMO

In view of the high risks brought about by organic micropollutants (OMPs), nanofiltration (NF) processes have been playing a vital role in advanced water and wastewater treatment, owing to the high membrane performance in rejection of OMPs, permeation of water, and passage of mineral salts. Though numerous studies have been devoted to evaluating and technically enhancing membrane performance in removing various OMPs, the trade-off effect between water permeance and water/OMP selectivity for state-of-the-art membranes remains far from being understood. Knowledge of this effect is significant for comparing and guiding membrane development works toward cost-efficient OMP removal. In this work, we comprehensively assessed the performance of 88 NF membranes, commercialized or newly developed, based on their water permeance and OMP rejection data published in the literature. The effectiveness and underlying mechanisms of various modification methods in tailoring properties and in turn performance of the mainstream polyamide (PA) thin-film composite (TFC) membranes were quantitatively analyzed. The trade-off effect was demonstrated by the abundant data from both experimental measurements and machine learning-based prediction. On this basis, the advancement of novel membranes was benchmarked by the performance upper-bound revealed by commercial membranes and lab-made PA membranes. We also assessed the potentials of current NF membranes in selectively separating OMPs from inorganic salts and identified the future research perspectives to achieve further enhancement in OMP removal and salt/OMP selectivity of NF membranes.


Assuntos
Membranas Artificiais , Purificação da Água , Estudos Prospectivos , Sais , Purificação da Água/métodos , Nylons , Água
16.
Anal Bioanal Chem ; 414(23): 6779-6789, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35879424

RESUMO

An intramolecular charge transfer (ICT)-based fluorescent probe P-ONOO- was synthesized to detect ONOO-. After responding to peroxynitrite, the dicyano-vinyl group of P-ONOO- generates the aldehyde group, emitting strong green fluorescence accompanied by quenching of the yellow fluorescence. According to the calculated Fukui function, the modification of the alkoxy group can enhance the f+ of P-ONOO-, which can enhance the probe's nucleophilic addition reactivity with ONOO-. It has been experimentally verified that P-ONOO- shows fast response (within 30 s), excellent sensitivity (the detection limit = 10.4 nM), and good selectivity towards ONOO-. Additionally, the probe P-ONOO- has high membrane permeability and good biocompatibility, which can image endogenous ONOO- and exogenous ONOO- in HeLa cells.


Assuntos
Corantes Fluorescentes , Ácido Peroxinitroso , Álcoois , Células HeLa , Humanos , Espectrometria de Fluorescência/métodos
17.
Mikrochim Acta ; 190(1): 8, 2022 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-36472666

RESUMO

A magnetic molecularly imprinted probe (MMIP@QD) was synthesized by reverse microemulsion method using CdTe QDs, Fe3O4, and molecularly imprinted polymer as the fluorophore, magnetic carrier, and recognition sites, respectively. The nanoparticle was characterized by transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectroscopy, and vibrating sample magnetometry (VSM). In the optimal experimental condition, fluorescent emission intensity (measured at excitation wavelengths of 350 nm) was quenched linearly with increasing malachite green (MG) concentration from 0.8 to 28.0 µM with LOD of 0.67 µM. Simultaneously, it was observed that the maximum absorption wavelength was blue shifted gradually with the increase of MG concentration. The inner filter effect, static quenching, and band gap transition were interpreted as the mechanisms of fluorescence quenching and wavelength shift. Thermodynamic studies indicated that the quenching reaction proceeded spontaneously. The developed sensor was applied to detect MG in seawater samples. Satisfactory recoveries of MG in spiked seawater ranged from 83.6 to 122.1% with RSD < 1.8%.


Assuntos
Compostos de Cádmio , Nanopartículas de Magnetita , Pontos Quânticos , Espectroscopia de Infravermelho com Transformada de Fourier , Telúrio
18.
Nat Methods ; 15(12): 1083-1089, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30504871

RESUMO

Single-particle electron cryomicroscopy (cryo-EM) involves estimating a set of parameters for each particle image and reconstructing a 3D density map; robust algorithms with accurate parameter estimation are essential for high resolution and automation. We introduce a particle-filter algorithm for cryo-EM, which provides high-dimensional parameter estimation through a posterior probability density function (PDF) of the parameters given in the model and the experimental image. The framework uses a set of random support points to represent such a PDF and assigns weighting coefficients not only among the parameters of each particle but also among different particles. We implemented the algorithm in a new program named THUNDER, which features self-adaptive parameter adjustment, tolerance to bad particles, and per-particle defocus refinement. We tested the algorithm by using cryo-EM datasets for the cyclic-nucleotide-gated (CNG) channel, the proteasome, ß-galactosidase, and an influenza hemagglutinin (HA) trimer, and observed substantial improvement in resolution.


Assuntos
Algoritmos , Microscopia Crioeletrônica/métodos , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Software , Canais de Cátion Regulados por Nucleotídeos Cíclicos/ultraestrutura , Glicoproteínas de Hemaglutininação de Vírus da Influenza/ultraestrutura , Humanos , Complexo de Endopeptidases do Proteassoma/ultraestrutura , beta-Galactosidase/ultraestrutura
19.
Brief Bioinform ; 20(6): 2291-2298, 2019 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-30169568

RESUMO

Genetic risk score (GRS, also known as polygenic risk score) analysis is an increasingly popular method for exploring genetic architectures and relationships of complex diseases. However, complex diseases are usually measured by multiple correlated phenotypes. Analyzing each disease phenotype individually is likely to reduce statistical power due to multiple testing correction. In order to conquer the disadvantage, we proposed a principal component analysis (PCA)-based GRS analysis approach. Extensive simulation studies were conducted to compare the performance of PCA-based GRS analysis and traditional GRS analysis approach. Simulation results observed significantly improved performance of PCA-based GRS analysis compared to traditional GRS analysis under various scenarios. For the sake of verification, we also applied both PCA-based GRS analysis and traditional GRS analysis to a real Caucasian genome-wide association study (GWAS) data of bone geometry. Real data analysis results further confirmed the improved performance of PCA-based GRS analysis. Given that GWAS have flourished in the past decades, our approach may help researchers to explore the genetic architectures and relationships of complex diseases or traits.


Assuntos
Predisposição Genética para Doença , Simulação por Computador , Estudo de Associação Genômica Ampla , Humanos , Fenótipo , Análise de Componente Principal
20.
Opt Lett ; 46(17): 4100-4103, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34469949

RESUMO

We present a firmly arranged dielectric regular hexagonal pyramid array to generate lattice light sheets with high conversion efficiency and low stray light. Both the size and working distance of the lattice light sheets can be modulated by changing the structural parameters. We experimentally recorded the lattice light sheets illumination, which is consistent with the corresponding simulation. To evaluate the imaging quality, we compared the light field generated with and without structure by using polystyrene fluorescent microspheres. This study provides a potential method for the building of light sheet fluorescence microscopy with high resolution and low phototoxicity.

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