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1.
Sensors (Basel) ; 24(2)2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-38257557

RESUMEN

It is important to maintain the safety of road driving by automatically performing a series of processes to automatically measure and repair damage to the road pavement. However, road pavements include not only damages such as longitudinal cracks, transverse cracks, alligator cracks, and potholes, but also various elements such as manholes, road marks, oil marks, shadows, and joints. Therefore, in order to separate categories that exist in various road pavements, in this paper, 13,500 digital, IR, and MSX images were collected and nine categories were automatically classified by DarkNet. The DarkNet classification accuracies of digital images, IR images, and MSX images are 97.4%, 80.1%, and 91.1%, respectively. The MSX image is a enhanced image of the IR image and showed an average of 6% lower accuracy than the digital image but an average of 11% higher accuracy than the IR image. Therefore, MSX images can play a complementary role if DarkNet classification is performed together with digital images. In this paper, a method for detecting the directionality of each crack through a two-dimensional wavelet transform is presented, and this result can contribute to future research on detecting cracks in pavements.

2.
J Mol Model ; 29(5): 138, 2023 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-37055578

RESUMEN

CONTEXT: In the replication of SARS-CoV-2, the main protease (Mpro/3CLpro) is significant. It is conserved in a number of novel coronavirus variations, and no known human proteases share its cleavage sites. Therefore, 3CLpro is an ideal target. In the report, we screened five potential inhibitors (1543, 2308, 3717, 5606, and 9000) of SARS-CoV-2 Mpro through a workflow. The calculation of MM-GBSA binding free energy showed that three of the five potential inhibitors (1543, 2308, 5606) had similar inhibitor effects to X77 against Mpro of SARS-CoV-2. In conclusion, the manuscript lays the groundwork for the design of Mpro inhibitors. METHODS: In the virtual screening phase, we used structure-based virtual screening (Qvina2.1) and ligand-based virtual screening (AncPhore). In the molecular dynamic simulation part, we used the Amber14SB + GAFF force field to perform molecular dynamic simulation of the complex for 100 ns (Gromacs2021.5) and performed MM-GBSA binding free energy calculation according to the simulation trajectory.


Asunto(s)
Proteasas 3C de Coronavirus , Inhibidores de Proteasa de Coronavirus , Simulación de Dinámica Molecular , SARS-CoV-2 , Humanos , Endopeptidasas , Simulación del Acoplamiento Molecular , Farmacóforo , SARS-CoV-2/enzimología , Proteasas 3C de Coronavirus/antagonistas & inhibidores , Inhibidores de Proteasa de Coronavirus/química , Inhibidores de Proteasa de Coronavirus/farmacología
3.
Sensors (Basel) ; 22(23)2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36502066

RESUMEN

Deep learning techniques underpinned by extensive data sources encompassing complex pavement features have proven effective in early pavement damage detection. With pavement features exhibiting temperature variation, inexpensive infra-red imaging technology in combination with deep learning techniques can detect pavement damages effectively. Previous experiments based on pavement data captured during summer sunny conditions when subjected to SA-ResNet deep learning architecture technique demonstrated 96.47% prediction accuracy. This paper has extended the same deep learning approach to a different dataset comprised of images captured during winter sunny conditions to compare the prediction accuracy, sensitivity and recall score with summer conditions. The results suggest that irrespective of the prevalent weather season, the proposed deep learning algorithm categorises pavement features around 92% accurately (95.18% in summer and 91.67% in winter conditions), suggesting the beneficial replacement of one image type with other. The data captured in sunny conditions during summer and winter show prediction accuracies of DC = 96.47% > MSX = 95.24% > IR-T = 93.83% and DC = 94.14% > MSX = 90.69% > IR-T = 90.173%, respectively. DC images demonstrated a sensitivity of 96.47% and 94.20% for summer and winter conditions, respectively, to demonstrate that reliable categorisation is possible with deep learning techniques irrespective of the weather season. However, summer conditions showing better overall prediction accuracy than winter conditions suggests that inexpensive IR-T imaging cameras with medium resolution levels can still be an economical solution, unlike expensive alternate options, but their usage has to be limited to summer sunny conditions.


Asunto(s)
Aprendizaje Profundo , Tiempo (Meteorología) , Algoritmos , Estaciones del Año , Diagnóstico por Imagen
4.
Virol J ; 19(1): 14, 2022 01 20.
Artículo en Inglés | MEDLINE | ID: mdl-35057815

RESUMEN

BACKGROUND: The Alphapapillomavirus 9 (α-9 HPV) is a member of the Alphapapillomavirus genus and Papillomaviridae family. These viruses are almost all carcinogenic HPV, which is closely related to 75% of invasive cervical cancer worldwide, and has a high prevalence in Sichuan. The carcinogenic function is mainly realized by its E6 oncoprotein. METHODS: Cell samples were collected by cervical scraped for HPV detecting and typing. HPV-16, HPV-31, HPV-33, HPV-52, HPV-58 5 α-9 genus HPV subtype positive samples were selected, their E6 gene was sequenced and analyzed. The positive selection sites of HPV E6 genes were estimated by PAML 4.8 server. The secondary and tertiary structure of E6 protein were predicted by PSIPred and Swiss-model. The T-cell antigen epitopes of E6 protein were predicted by IEDB. RESULTS: α-9 HPV has a high prevalence in Sichuan, China. From 2012 to 2017, 18,067 cell cervical samples were collected, and 3135 were detected with α-9 HPV infection. Among which, 250 cases HPV-16 E6, 96 cases HPV-31 E6, 216 cases HPV-33 E6, 288 cases HPV-52 E6 and 405 cases HPV-58 E6 were successfully amplified, 17, 6, 6, 13, and 4 non-synonymous nucleotide mutations were respectively detected in HPV-16, 31, 33, 52, and 58 E6, 7 positive selection sites of α-9 HPV E6 were selected out (D32E of HPV-16 E6, K35N, K93N and R145I of HPV-33 E6, K93R of HPV-52 E6, K93N and R145K of HPV-58 E6). The structure and antigen epitopes of E6 protein with amino acid substitution differ from those of wild-type E6 protein, especially for the mutation located in the E6 positive selection site. CONCLUSIONS: HPV E6 nucleotide non-synonymous mutation in the positive selection site influence the protein structure and decrease the antigen epitopes affinity of the E6 protein overall, making it more difficult for the HPV-infected cells to be detected by the immune system, and enhancing the HPV adaptability to the environment. Mutations influence the validity of HPV clinical diagnostic probes, the polymorphism analysis of α-9 HPV E6 enrich the data of HR-risk HPV in Sichuan China, and the detection probes designed with the polymorphism data in mind can improve the efficiency of clinical detection; Mutations influence epitopes affinity, the association of E6 polymorphism and epitope affinity can improve the design of therapeutic vaccine with good immunity and high generality antigen epitope; The above study all provide a good theoretical basis for the prevention and treatment of HPV-related diseases.


Asunto(s)
Alphapapillomavirus , Proteínas Oncogénicas Virales , Proteínas Represoras , Alphapapillomavirus/genética , China/epidemiología , Epítopos de Linfocito T/genética , Femenino , Papillomavirus Humano 16 , Humanos , Proteínas Oncogénicas Virales/química , Proteínas Oncogénicas Virales/genética , Infecciones por Papillomavirus , Filogenia , Polimorfismo de Nucleótido Simple , Proteínas Represoras/química , Proteínas Represoras/genética , Neoplasias del Cuello Uterino
5.
J Mater Chem B ; 9(13): 3047-3054, 2021 04 07.
Artículo en Inglés | MEDLINE | ID: mdl-33885666

RESUMEN

Prenatal diagnostics holds great significance for pregnant women desiring healthy babies. Fetal nucleated red blood cells (fNRBCs), bearing the complete genome of the fetus, have been regarded as an important biomarker for noninvasive prenatal diagnostics (NIPD). The high-performance detection and enrichment of fNRBCs from maternal blood, especially during early pregnancy, is urgently needed for NIPD, which, unfortunately, remains a big challenge for early-pregnancy fNRBC isolation. In this study, we developed an innovative platform based on silica microbeads for fNRBC isolation and release in early pregnancy. Microbeads were coated with self-assembled MnO2 nanoparticles (SiO2@MnO2) and then modified with a specific antibody. Benefiting from the three-dimensional nanostructure of the MnO2 nanoparticles, the isolation efficiency of the fNRBCs was enhanced. Subsequently, fNRBCs were released via dissolving the MnO2-nanoparticle coating using oxalic acid. We successfully isolated fNRBCs from the maternal peripheral blood samples of 20 pregnant women in the early pregnancy period, ranging from 41 to 62 gestational days. More importantly, the fetal origin of isolated cells was confirmed via fluorescent in situ hybridization and short tandem repeat analysis. This platform based on SiO2@MnO2 microbeads has verified the existence of fNRBCs in early-pregnancy maternal blood and is a promising approach for NIPD in early pregnancy.


Asunto(s)
Eritrocitos/citología , Sangre Fetal/citología , Microesferas , Nanoestructuras/química , Diagnóstico Prenatal , Femenino , Humanos , Compuestos de Manganeso/química , Óxidos/química , Embarazo , Dióxido de Silicio/química
6.
ACS Chem Neurosci ; 11(24): 4007-4011, 2020 12 16.
Artículo en Inglés | MEDLINE | ID: mdl-33271013

RESUMEN

Despite intense efforts, the cause of Alzheimer's disease is still not fully understood. A chemical and biochemical perspective could shed light on this disorder. Secondary chemical bonding between calcium and carbonyl oxygen atoms of glycine and valine might give rise to aggregates in the brain, which may later result in cell senescence. The decrease of solubility caused by amino acid substitutions in specific risk factors compounds insolubility issue and likely triggers early-onset Alzheimer's disease. Occasionally the enhancement of hydrogen bonding by amino acid replacements can reinforce the aggregates. Therefore, secondary chemical bonding to cations can generate cellular stresses in patients with Alzheimer's disease in addition to other chemical and biochemical interactions such as salt bridge. The distinction between early-onset and late-onset Alzheimer's disease risk factors may lie in the total capacity of a protein or local potency of a protein fragment to bind calcium or/and oxalate as calcium oxalate is highly insoluble and stressful.


Asunto(s)
Enfermedad de Alzheimer , Péptidos beta-Amiloides , Péptidos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Oxalato de Calcio , Glicina , Humanos , Oxígeno , Valina
7.
J Int Med Res ; 48(6): 300060520929853, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32529876

RESUMEN

Numerous risk factors for heart disease or dementia harbor over 10% valine plus glycine content. Interestingly, TDP-43 contains 6.0% valine and 13.3% glycine, and the buildup of this protein in the brains of patients with limbic-predominant age-related TDP-43 encephalopathy has dire consequences. The two γ-methyl groups in valine enable hyperconjugation, which enhances the van der Waals interaction between its side group and the carbonyl carbon. This extends the C=O bond length, and this weakened C=O bond augments the secondary chemical bonding of the carbonyl oxygen atom to cations. This, in turn, promotes the formation and buildup of insoluble and rigid salts such as calcium oxalate, which is postulated to be a major cause of heart disease. Similarly, the long C=O bond length in glycine results in a weakened C=O bond with an enhanced affinity toward cations and the formation of insoluble salts. Further, several prion proteins possess a high glycine content of approximately 20%. The insoluble calcium salts produced may promote aggregate formation via secondary chemical bonding between calcium and glycine, as well as between calcium and valine. Chemical and biochemical insights will help us to better understand the etiology of disorders linked to protein aggregates.


Asunto(s)
Encéfalo/patología , Proteínas de Unión al ADN/química , Glicina/química , Proteinopatías TDP-43/etiología , Factores de Edad , Anciano de 80 o más Años , Secuencia de Aminoácidos , Proteínas de Unión al ADN/genética , Glicina/genética , Humanos , Agregado de Proteínas/genética , Factores de Riesgo , Proteinopatías TDP-43/epidemiología , Proteinopatías TDP-43/patología , Valina/química , Valina/genética
18.
Med Hypotheses ; 108: 52-53, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29055401

RESUMEN

Hepatitis B virus is a major pathogen infecting the liver, causing high morbidity and mortality worldwide, particularly in developing countries. The mechanism underlying progression from infections of Hepatitis B virus to cirrhosis and liver cancer is not fully determined. Here we propose that the HBV X protein traps protons and Cl-, and induces the expression of collagen in the liver, which forms potent hydrogen bonds with trapped protons. The presence of collagen in the liver marks the progression to fibrosis. The X protein and collagen concertedly build up HCl locally, triggering disease advances to liver cancer in some patients with liver cirrhosis. The hypothesis can be tested in Hepatitis B primate model with the administration of calcium and weak acids to ascertain physiological changes and monitor tumorigenesis rate. The experiments will pave the way for better intervention of human infections with Hepatitis B virus.


Asunto(s)
Carcinoma Hepatocelular/virología , Virus de la Hepatitis B , Hepatitis B Crónica/virología , Cirrosis Hepática/virología , Neoplasias Hepáticas/virología , Carcinoma Hepatocelular/complicaciones , Colágeno/metabolismo , Progresión de la Enfermedad , Hepatitis B Crónica/complicaciones , Humanos , Enlace de Hidrógeno , Cirrosis Hepática/complicaciones , Neoplasias Hepáticas/complicaciones , Modelos Biológicos , Modelos Teóricos , Protones , Transactivadores/metabolismo , Proteínas Reguladoras y Accesorias Virales
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