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1.
J Neurosci Methods ; 409: 110184, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38838748

RESUMO

OBJECTIVE: this study was to analyze the brain functional network of end-of-dose wearing-off (EODWO) in patients with Parkinson's disease (PD) using a convolutional neural network (CNN)-based functional magnetic resonance imaging (fMRI) data classification model. METHODS: one hundred PD patients were recruited and assigned to control (Ctrl) group (39 cases without EODWO) and experimental (Exp) group (61 cases with EODWO). The data classification model based on a CNN was employed to assist the analysis of the changes in brain functional network structure in the two groups. The CNN-based fMRI data classification model was primarily based on a CNN architecture, with improvements made to the initialization of convolutional kernel parameters. Firstly, a structure based on restricted Boltzmann machine (RBM) was constructed, followed by the initialization of convolutional kernel parameters. Subsequently, the model underwent training. Utilizing the data analysis module within the GRETNA toolbox, extracted feature sets were analyzed, including local measures such as betweenness centrality (BC) and degree centrality (DC), as well as global measures such as global efficiency (Eg) and local efficiency (Eloc). RESULTS: as sparsity increased, there was a gradual upward trend observed in Eg; however, the values of Eg in both brain functional networks remained relatively stable within the range of 0.2-0.5. The Eg value of the Ctrl group's whole-brain functional network was 0.17 ± 0.02, while that of the Exp group's whole-brain functional network was 0.17 ± 0.03, with no significant difference between them (P>0.05). The functional DC value of the superior frontal gyrus in the Exp group (8.71 ± 2.56) was significantly lower than that of the Ctrl group (13.32 ± 3.22), whereas the functional DC value of the anterior cingulate gyrus in the Exp group (19.33 ± 4.78) was significantly higher than that of the Ctrl group (15.21 ± 4.02) (P<0.05). There was no significant correlation observed between the functional DC value and levodopa or dopamine agonist therapy (DDT) in the Exp group, whereas the Ctrl group exhibited a significant positive correlation. CONCLUSION: analysis conducted via a CNN-based fMRI data classification model revealed a correlation between the occurrence of EODWO in PD patients and functional impairments in the left precuneus. Additionally, the occurrence of EODWO may potentially diminish the plasticity of the central prefrontal dopamine.

2.
Plants (Basel) ; 13(7)2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38611453

RESUMO

With global climate change and accelerating urbanization, marine cities face unique environmental challenges. Ecological landscape creation is a form of design planning guided by the disciplines of landscape ecology and ecological aesthetics in the process of urban planning and construction. It seeks a design that can maintain the virtuous cycle of the ecosystem and at the same time maintain the spatial equilibrium of the dynamic development of urban landscapes, so as to make them have good ecological functions and corridor functions. The aim of this study is to explore the ecological design methods of plant landscaping in marine urban green spaces under the concept of sustainability. We first reviewed the concept of sustainable development and its application to urban green space design, especially the special requirements in the marine urban environment. This research focuses on how to select plant species that are adapted to the marine climate and how to promote biodiversity, enhance ecosystem services, and improve the quality of life of urban residents through eco-design approaches. Through the analysis of a number of domestic and international cases of green spaces in marine cities, we found that effective eco-design is not only about choosing the right plant species but also includes the rational management of water resources, soil protection, and ecosystem restoration, among other aspects. This study also points out that public participation and interdisciplinary cooperation play a crucial role in the ecological design process. Finally, this paper carries out a specific analysis of the landscape model landscape evaluation system for the ecological design of plant landscaping in marine urban green spaces and experimentally verifies that, compared with other styles, the experience of the European-style landscape is good overall. However, the view openness rating of the European style landscape is only about 0.42, and the best plant landscaping is the mixed mode of alkali poncho and salt poncho. This study aims to provide a practical reference and guidance for urban planners, landscape architects, and environmentalists.

3.
Curr Drug Metab ; 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38509677

RESUMO

BACKGROUND: BK virus (BKV) infection is an opportunistic infectious complication and constitutes a risk factor for premature graft failure in kidney transplantation. Our research aimed to identify associations and assess the impact of single-nucleotide polymorphisms (SNPs) on metabolism-related genes in patients who have undergone kidney transplantation with BKV infection.

Material/Methods: The DNA samples of 200 eligible kidney transplant recipients from our center, meeting the inclusion criteria, have been collected and extracted. Next-generation sequencing was used to genotype SNPs on metabolism-associated genes (CYP3A4/5/7, UGT1A4/7/8/9, UGT2B7). A general linear model (GLM) was used to identify and eliminate confounding factors that may influence the outcome events. Multiple inheritance models and haplotype analyses were utilized to identify variation loci associated with infection caused by BKV and ascertain haplotypes, respectively.

Results: A total of 141 SNPs located on metabolism-related genes were identified. After Hardy-Weinberg equilibrium (HWE) and minor allele frequency (MAF) analysis, 21 tagger SNPs were selected for further association analysis. Based on GLM results, no confounding factor was significant in predicting the incidence of BK polyomavirus-associated infection. Then, multiple inheritance model analyses revealed that the risk of BKV infection was significantly associated with rs3732218 and rs4556969. Finally, we detect significant associations between haplotype T-A-C of block 2 (rs4556969, rs3732218, rs12468274) and infection caused by BKV (P = 0.0004).

Conclusions: We found that genetic variants in the UGT1A gene confer BKV infection susceptibility after kidney transplantation.

4.
Biomed Pharmacother ; 164: 114986, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37295251

RESUMO

BACKGROUND: 5-Fluorouracil (5-Fu) is one of the most commonly used chemotherapy drugs for gastric cancer (GC). But the increase of drug resistance makes the prognosis of patients worse. Studies have shown that Baicalin can not only inhibit various cancers but also increase the sensitivity of cancers to chemotherapy. However, how Baicalin works in chemotherapeutic resistance of GC are unclear. METHODS: CCK8 (Cell Counting Kit 8) was used to detect the IC50 (half maximal inhibitory concentration) of Baicalin and 5-Fu. Proliferation, migration, and invasion of GC were tested through colony formation assay and transwell assay. Fluorescent probes detected intracellular reactive oxygen species (ROS). RNA-seq (RNA sequencing) detected differentially expressed genes and pathways, and qPCR (Quantitative Real-time PCR) tested the expression of ferroptosis-related genes. RESULTS: The combination of Baicalin and 5-Fu inhibited GC progression and increased intracellular ROS levels. Both the inhibition of malignant phenotype of gastric cancer cells and the generation of intracellular ROS caused by Baicalin could be saved by the inhibitor of ferroptosis-Ferrostatin-1 (Fer-1). Heat map of enriched differentially expressed genes identified by RNA-seq included four ferroptosis-related genes, and subsequent GO (Gene Ontology) analysis suggested an association between the ferroptosis pathway and Baicalin treatment. The changes in expression of ferroptosis-related genes were validated by qPCR, and the result confirmed that the combination of Baicalin and 5-Fu promoted ferroptosis in GC. CONCLUSIONS: Baicalin inhibits GC and enhances 5-Fu by promoting ROS-related ferroptosis in GC.


Assuntos
Ferroptose , Neoplasias Gástricas , Humanos , Fluoruracila/farmacologia , Fluoruracila/uso terapêutico , Neoplasias Gástricas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Linhagem Celular Tumoral
5.
Front Oncol ; 13: 1192192, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37274227

RESUMO

Objective: The intent of this study was to investigate the relationship between oxidative stress and treatment response in gastric cancer patients undergoing neoadjuvant chemotherapy. Methods: Blood samples from 108 patients and 108 healthy subjects were collected, and all patients were enrolled in SOX chemotherapy. The patients received four cycles of neoadjuvant chemotherapy. Blood samples were collected to determine oxidative stress levels at baseline prior to beginning chemotherapy, and at the end of cycles 2 and 4. The patients receiving neoadjuvant chemotherapy were followed up for several months to years. A survival curve was created according to the follow-up information from the patients. In addition, the correlation between oxidative stress level and treatment effect was evaluated and ROC curves were plotted according to the final collected data. Results: Compared with the normal group, the levels of the antioxidant index decreased while the peroxide index increased in the patients. Conversely, when patients were compared before and after chemotherapy, the antioxidant index increased but the peroxide index decreased. Furthermore, the antioxidant index increased in the response group while the peroxide index decreased in the non-response group. Conclusion: Patients with an increased antioxidant index after chemotherapy have good treatment responsiveness. These indicators can also be used as predictors to judge the patients' response to chemotherapy.

6.
Plants (Basel) ; 12(7)2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-37050057

RESUMO

At present, there is a growing focus on the landscape and environment of ocean cities, with an increasing demand for improved ecological sustainability and aesthetic appeal. With the emergence of computer vision design technologies such as 3D and VR, people have overcome the limitations of traditional paper-based design materials. Through the use of computer software, various forms of expression, such as drawings and animations, can be produced, thereby meeting the diverse demands for showcasing plant landscapes. The purpose of this paper is to study the design of marine urban (MU) botanical landscapes based on computer vision technology (CVT) and multimodal interaction design (MID) theory, so that the design of MU botanical landscape can meet people's psychological behavior and visual needs, and at the same time enable people to participate in and experience the landscape, so as to better meet people's needs for viewing, leisure, and entertainment. At the same time, it is hoped that the research of this paper will play a role in promoting the innovation and development of the concept of MU landscape design (LD) in the future, specifically from two levels of theoretical and practical significance. First, at the level of theoretical research: Based on the theory of MID, this paper explores the application of communication and interaction among humans and between humans and the landscape in the design of MU planting, and tries to explore and summarize the content and methods of interactive LD in marine cities with a theoretical basis and research value. The goal is to both enhance the theoretical level of interactive LD, and also provide new reference for future marine city (MC) LD. Second, at the level of practical application: In the field of LD, the new concept of computer vision is introduced to fully understand the visual needs of people and increase the practicality and pleasantness of the MU landscape, hoping to attract more people to come to play and rest. Through the attraction of MU landscapes to tourists, the design and construction of the landscape no longer focus on its appearance, but rather on the participation and experience of people.

7.
Cancer Sci ; 114(4): 1353-1364, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36522839

RESUMO

Multidrug resistance is a primary factor in the poor response to chemotherapy and subsequent death in gastric cancer patients. However, the molecular mechanisms involved remain unclear. In this study, the high expression of special AT-rich sequence binding protein 1 (SATB1) in gastric cancer was found to be associated with reduced sensitivity to various chemotherapy drugs. Our results demonstrate that SATB1 can promote chemotherapy resistance in gastric cancer in vitro and in vivo. SATB1 exerts its effect by enhancing the activity of multiple ATP-binding cassette (ABC) transporters (P-glycoprotein, multidrug resistance-associated protein, and breast cancer resistance protein) in gastric cancer cell lines. We also found that SATB1 affects ABC transporters by altering the subcellular localization of the ABC transporter rather than its expression. Subsequently, we confirmed that Ezrin binds to various ABC transporters and affects their subcellular localization. In addition, we found that SATB1 can also bind to the Ezrin promoter and regulate its expression. In the present study, we elucidate the mechanism of SATB1-mediated multidrug resistance in gastric cancer, providing a basis for SATB1 as a potential target for reversal of resistance.


Assuntos
Proteínas de Ligação à Região de Interação com a Matriz , Neoplasias Gástricas , Humanos , Transportadores de Cassetes de Ligação de ATP/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Proteínas de Ligação à Região de Interação com a Matriz/genética , Proteínas de Ligação à Região de Interação com a Matriz/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas de Neoplasias/metabolismo , Resistência a Múltiplos Medicamentos/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Proteínas Associadas à Resistência a Múltiplos Medicamentos/farmacologia
8.
Pharmaceutics ; 14(10)2022 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-36297544

RESUMO

(1) Background: Gastric cancer (GC) is the fourth leading cause of cancer death worldwide. Silver nanoparticles (Ag-NPs) have been increasingly used in the diagnosis and treatment of cancer due to their physicochemical properties. This study investigated the role of a kind of biosynthetic silver nanoparticle (b-Ag) in the development of GC, the enhancement of 5-fluorouracil (5F), and its mechanism. (2) Methods: X-ray, transmission electron microscopy (TEM), and UV absorbance were used to detect the characterizations of AgNPs. CCK8, Colony formation and a Transwell assay were performed to confirm the malignant behaviors of GC. DCFH-DA and DHE were used to detect intracellular reactive oxygen species (ROS). Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to detect the mRNA expression of apoptosis-related genes. (3) Results: Compared with the chemosynthetic silver nanoparticles (c-Ag), b-Ag had a stronger cytokilling effect, and it had a better inhibition on the malignant phenotype of GC when combined with 5F. The b-Ag increased the expression of Bax and P53 while decreasing the expression of Bcl2. It also promoted the generation of intracellular ROS. (4) Conclusions: By promoting cell apoptosis and increasing intracellular ROS, b-Ag inhibited the development of GC and enhanced the inhibition of 5F on GC.

9.
Cancers (Basel) ; 14(14)2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35884594

RESUMO

Gastric cancer (GC) is among the most lethal tumors worldwide. Long noncoding RNAs (lncRNAs) are reported to be critical during the occurrence and progression of malignancies. The HOXC cluster antisense RNA 1 (HOXC-AS1) has been suggested to participate in the genesis and development of GC. Therefore, we examined GC cells and tissues for the expression of HOXC-AS1 and correlated the expression levels with the disease specific survival of the patients, finding that HOXC-AS1 was overexpressed and probably had a tendency of leading to a poor prognosis. The Cell Counting Kit-8 assay and colony formation assay were then performed under knockdown of HOXC-AS1, revealing that cell proliferation of GC was distinctly decreased. Afterwards, miR-99a-3p was predicted to bind with HOXC-AS1 by DIANA tools. We carried out dual-luciferase reporter gene assays to identify the interaction between them. After knockdown of HOXC-AS1, miR-99a-3p was clearly overexpressed in GC cells. In addition, matrix metalloproteinase 8 (MMP8) was shown to be combined with miR-99a-3p using TargetScan. Similar experiments, along with western blot, were conducted to validate the correlation between miR-99a-3p and MMP8. Finally, rescue experiments for CCK-8 were completed, disclosing that HOXC-AS1 promoted cell progression of GC through sponging miR-99a-3p followed by subsequent upregulation of MMP8.

10.
Mediators Inflamm ; 2022: 1894379, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35712055

RESUMO

Intestinal epithelial cells are an essential barrier in human gastrointestinal tract, and healing of epithelial wound is a key process in many intestinal diseases. α-Lipoic acid (ALA) was shown to have antioxidative and anti-inflammatory effects, which could be helpful in intestinal epithelial injury repair. The effects of ALA in human colonic epithelial cells NCM460 and human colorectal adenocarcinoma cells Caco-2 were studied. ALA significantly promoted NCM460 and Caco-2 migration, increased mucosal tight junction factors ZO-1 and OCLN expression, and ALA accelerated cell injury repair of both cells in wound healing assay. Western blot analysis indicated that ALA inhibited a variety of mitogen-activated protein kinase (MAPK) signaling pathways in the epithelial cells. In conclusion, ALA was beneficial to repair of intestinal epithelial injury by regulating MAPK signaling pathways.


Assuntos
Mucosa Intestinal , Sistema de Sinalização das MAP Quinases , Ácido Tióctico , Células CACO-2 , Células Epiteliais/metabolismo , Humanos , Mucosa Intestinal/lesões , Mucosa Intestinal/metabolismo , Intestinos/patologia , Ácido Tióctico/farmacologia
11.
Front Oncol ; 12: 830688, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35515139

RESUMO

Gastric cancer (GC) is the third leading cause of tumor related mortality worldwide. Peritoneal metastasis (PM) occurs in more than half of advanced GC patients, leading to poor prognosis. Therefore, the GSE62254 cohort was used to construct a signature consisting of four RNA-binding proteins (RBP) to predict the possibility of PM in GC patients. Then, ROC curves were plotted followed by calculation of AUCs, showing that the signature had a similar predictive accuracy compared with the TNM staging system. Importantly, the capability of prediction was enhanced by combining the classifier and TNM staging. In order to validate the expression of the four RBPs in GC tissues with and without PM, immunohistochemistry was further performed on samples from 108 patients. The differential expression of COL14A1, TNS1, NUSAP1 and YWHAE was in accordance with the emergence of PM. Afterwards, we produced Kaplan-Meier curves according to the signature and differential expression of the RBPs in patients. Finally, CCK-8 assays were performed to verify the effect on cell proliferation, finding that COL14A1 and TNS1 promoted cell proliferation, while NUSAP1 and YWHAE led to suppressed cell proliferation. In conclusion, the four-RBP-based signature, combined with TNM staging, has the potential to predict risk of PM in GC.

12.
Small ; 18(5): e2106498, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34921576

RESUMO

Cell morphology and migration depend critically on the adhesions on the extracellular matrix (ECM), determined by the transmembrane protein integrins. The epithelial to mesenchymal transition (EMT) is a prominent transformation process in which adherent cells acquire a mesenchymal phenotype and a promoted migration. EMT plays important roles in embryonic development and cancer metastasis, and its hallmarks include the acquisition of front-back cell polarity and loss of cell-cell contact. However, how integrins dynamically regulate cell-ECM adhesions and cellular behaviors during EMT is still unclear. Using single-particle tracking of ß1-integrins labeled with quantum dots, the temporal-spatial on-membrane dynamics of integrins in the EMT of MCF10A cells is revealed. ß1-integrins exhibit significantly enhanced dynamics, which temporally behave more diffusive and less immobilized, and spatially become distributed asymmetrically with front regions being more dynamic. These dynamic alterations are shown to arise from microtubule remodeling in EMT. The results shed new light on the EMT mechanism from the cell-ECM adhesion perspective, and suggest that the enhanced integrin diffusion may represent as a new hallmark of EMT.


Assuntos
Transição Epitelial-Mesenquimal , Integrinas , Movimento Celular , Células Epiteliais , Transição Epitelial-Mesenquimal/genética , Matriz Extracelular/metabolismo , Integrinas/metabolismo , Transdução de Sinais
13.
J Org Chem ; 86(24): 17944-17954, 2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-34872249

RESUMO

An efficient and straightforward synthesis of polysubstituted oxazol-2(3H)-ones has been developed via a tandem Hofmann-type rearrangement and cyclization reaction of various α-acyl-ß-aminoacrylamides mediated by phenyl iodine(III) bis(trifluoroacetate) (PIFA) in the presence of trifloroacetic acid (TFA). This novel protocol features readily available starting materials, mild reaction conditions, simple execution, high chemoselectivity, good functional group tolerance, and a metal-free oxidation process.

14.
Mediators Inflamm ; 2021: 8698923, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34456630

RESUMO

OBJECTIVE: To explore the value of the heart rate, body temperature, and respiratory rate in the early prediction of anastomotic leakage after rectal cancer surgery. METHODS: Clinical data from patients with rectal cancer who underwent anterior rectal resection in the Department of Gastroenterology, Renmin Hospital of Wuhan University, from January 2017 to December 2019 were collected and analyzed retrospectively. Based on the occurrence of anastomotic leakage after surgery, the patients were divided into two groups: those with and without anastomotic leakage. The quantitative values of the heart rate, body temperature, and respiration rate at day 7 postsurgery were compared between the two groups. The ROC curve was used to analyze their role in the early prediction of anastomotic leakage. RESULTS: Among 441 patients with rectal cancer, 30 (6.81%) had clinical anastomotic leakage and were diagnosed at 7 ± 3 days postsurgery. Within 7 days postsurgery, the heart rate, body temperature, and respiratory rate in the anastomotic leakage group were higher than those in the nonanastomotic leakage group. The differences in heart rate (1-5 d), body temperature (2-7 d), and respiratory rate (1-7 d) were statistically significant (P < 0.05). The three ROC curves were drawn, respectively. The predictive value of the heart rate is greatest at days 2-3 postsurgery. The predictive value of the body temperature is greatest at days 4-6 postsurgery. The predictive value of the respiratory rate is best at days 1-4 postsurgery. CONCLUSION: The changes of vital signs (heart rate, body temperature, and respiratory rate) have a certain value in the early prediction of anastomotic leakage after rectal cancer surgery. Observation of postoperative vital signs at 7 days postsurgery is helpful for the early diagnosis of anastomotic leakage.


Assuntos
Neoplasias Retais , Taxa Respiratória , Fístula Anastomótica/diagnóstico , Temperatura Corporal , Detecção Precoce de Câncer , Frequência Cardíaca , Humanos , Neoplasias Retais/cirurgia , Estudos Retrospectivos , Fatores de Risco
15.
Mediators Inflamm ; 2021: 9968642, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34257521

RESUMO

BACKGROUND: Early diagnosis of anastomotic leakage (AL) after rectal surgery can reduce the adverse effects of AL, thereby reducing morbidity and mortality. Currently, there are no accepted indicators or effective scoring systems that can clearly identify patients at risk of anastomotic leakage. METHODS: A prospective study with assessment of the diagnostic accuracy of oxidative stress level (CAT, SOD, MDA) in serum and drain fluid compared to white blood cell count (WBC), C-reactive protein (CRP), and neutrophil percentage (NEUT) in prediction of AL in patients undergoing elective rectal surgery with anastomosis. RESULTS: Most of the oxidative stress indicators we detected are of considerable significance in the diagnosis of anastomotic leakage. The level of MDA on postoperative day (POD)3 (areas under the curve (AUC): 0.831) and POD5 (AUC: 0.837) in the serum and on POD3 (AUC: 0.845) in the drain fluid showed the same excellent diagnostic accuracy as the level of CRP on the POD3 (AUC: 0.847) and POD5 (AUC: 0.896). CONCLUSIONS: The overall level of oxidative stress in serum and drain fluid is a reliable indicator for the early diagnosis of anastomotic leakage after rectal surgery. More specifically, among the redox indicators analyzed, MDA has almost the same predictive value as CRP, which provides another useful biomarker for the early diagnosis of anastomotic leakage.


Assuntos
Anastomose Cirúrgica/efeitos adversos , Fístula Anastomótica/metabolismo , Estresse Oxidativo , Neoplasias Retais/metabolismo , Idoso , Área Sob a Curva , Biomarcadores/metabolismo , Procedimentos Cirúrgicos do Sistema Digestório/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oxirredução , Período Pós-Operatório , Estudos Prospectivos , Curva ROC , Neoplasias Retais/cirurgia , Reto/cirurgia , Reprodutibilidade dos Testes , Risco , Fatores de Tempo
16.
Int J Appl Earth Obs Geoinf ; 103: 102503, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-35481227

RESUMO

In order to mitigate the spread of COVID-19, Wuhan was the first city to implement strict lockdown policy in 2020. Even though numerous researches have discussed the travel restriction between cities and provinces, few studies focus on the effect of transportation control inside the city due to the lack of the measurement and available data in Wuhan. Since the public transports have been shut down in the beginning of city lockdown, the change of traffic density is a good indicator to reflect the intracity population flow. Therefore, in this paper, we collected time-series high-resolution remote sensing images with the resolution of 1 m acquired before, during and after Wuhan lockdown by GF-2 satellite. Vehicles on the road were extracted and counted for the statistics of traffic density to reflect the changes of human transmissions in the whole period of Wuhan lockdown. Open Street Map was used to obtain observation road surfaces, and a vehicle detection method combing morphology filter and deep learning was utilized to extract vehicles with the accuracy of 62.56%. According to the experimental results, the traffic density of Wuhan dropped with the percentage higher than 80%, and even higher than 90% on main roads during city lockdown; after lockdown lift, the traffic density recovered to the normal rate. Traffic density distributions also show the obvious reduction and increase throughout the whole study area. The significant reduction and recovery of traffic density indicates that the lockdown policy in Wuhan show effectiveness in controlling human transmission inside the city, and the city returned to normal after lockdown lift.

17.
J Org Chem ; 85(7): 4695-4705, 2020 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-32149512

RESUMO

A facile and efficient direct synthesis of N-substituted 4H-pyrido[1,2-a]pyrimidin-4-imines is developed from α-acyl-ß-(2-aminopyridinyl)acrylamides mediated by triflic anhydride (Tf2O) in the presence of 2-chloropyridine. This amide activation protocol features mild reaction conditions, simple execution, excellent yields, and high chemoselectivity, and is also applied to the synthesis of substituted 4H-pyrido[1,2-a]pyrimidin-4-ones via a practical one-pot procedure.

18.
J Org Chem ; 83(24): 14999-15008, 2018 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-30444122

RESUMO

Cyclization of a variety of ß-aminoacrylamides in the presence of iodosobenzene (PhIO) is described. This process features mild reaction conditions, simple execution, and high chemoselectivity and thereby provides an efficient protocol for the divergent synthesis of substituted isoxazoles and 2 H-azirines via switchable N-O and N-C bond formation controlled by simply varying the ß-substituent R3 of the readily available substrates.

19.
Proc Natl Acad Sci U S A ; 115(48): 12118-12123, 2018 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-30429318

RESUMO

Intracellular transport of cellular proteins and organelles is critical for establishing and maintaining intracellular organization and cell physiology. Apoptosis is a process of programmed cell death with dramatic changes in cell morphology and organization, during which signaling molecules are transported between different organelles within the cells. However, how the intracellular transport changes in cells undergoing apoptosis remains unknown. Here, we study the dynamics of intracellular transport by using the single-particle tracking method and find that both directed and diffusive motions of endocytic vesicles are accelerated in early apoptotic cells. With careful elimination of other factors involved in the intracellular transport, the reason for the acceleration is attributed to the elevation of adenosine triphosphate (ATP) concentration. More importantly, we show that the accelerated intracellular transport is critical for apoptosis, and apoptosis is delayed when the dynamics of intracellular transport is regulated back to the normal level. Our results demonstrate the important role of transport dynamics in apoptosis and shed light on the apoptosis mechanism from a physical perspective.


Assuntos
Apoptose , Células/metabolismo , Citosol/metabolismo , Células A549 , Trifosfato de Adenosina/metabolismo , Transporte Biológico , Células/citologia , Fator de Crescimento Epidérmico/metabolismo , Receptores ErbB/metabolismo , Humanos
20.
Sensors (Basel) ; 18(7)2018 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-29966344

RESUMO

Class IV Flextensional Transducers (FTs) are the most popular among various FTs used as low-frequency and high power underwater acoustic sources. However, an undeniable fact exists in Class IV FTs is that the resonance frequency of breathing mode regulator used is fairly raised by its longitudinal driver stacks. In this research, a conformal driving Class IV FT in which the driver stacks are kept conformal with its oval shell was proposed aiming at the limitations of conventional driving Class IV FTs described above. The device exhibits competitive Transmitting Voltage Responses (TVRs) but much lower operation frequencies with respect to conventional driving Class IV FTs, through the designs of conformal and segmentally controlled driver stacks. Geometric parameters analysis was carried out extensively by Finite Element (FE) simulations for the design optimizations and then a conformal driving Class IV FT resonating at 510 Hz (45% approximately lower than that of conventional driving Class IV FT with the same shell geometry) was finalized. Subsequently the conformal driving Class IV was fabricated and tested in the anechoic tank experimentally. Good agreements of both FE predictions and experimental results demonstrate its low-frequency and small-size acoustic performance.

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