Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 27
Filtrar
1.
Sensors (Basel) ; 24(2)2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38257557

RESUMO

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.
Virol J ; 19(1): 14, 2022 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-35057815

RESUMO

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.


Assuntos
Alphapapillomavirus , Proteínas Oncogênicas Virais , Proteínas Repressoras , Alphapapillomavirus/genética , China/epidemiologia , Epitopos de Linfócito T/genética , Feminino , Papillomavirus Humano 16 , Humanos , Proteínas Oncogênicas Virais/química , Proteínas Oncogênicas Virais/genética , Infecções por Papillomavirus , Filogenia , Polimorfismo de Nucleotídeo Único , Proteínas Repressoras/química , Proteínas Repressoras/genética , Neoplasias do Colo do Útero
3.
Sensors (Basel) ; 22(23)2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36502066

RESUMO

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.


Assuntos
Aprendizado Profundo , Tempo (Meteorologia) , Algoritmos , Estações do Ano , Diagnóstico por Imagem
4.
J Mol Model ; 29(5): 138, 2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-37055578

RESUMO

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.


Assuntos
Proteases 3C de Coronavírus , Inibidores de Protease de Coronavírus , Simulação de Dinâmica Molecular , SARS-CoV-2 , Humanos , Endopeptidases , Simulação de Acoplamento Molecular , Farmacóforo , SARS-CoV-2/enzimologia , Proteases 3C de Coronavírus/antagonistas & inibidores , Inibidores de Protease de Coronavírus/química , Inibidores de Protease de Coronavírus/farmacologia
5.
Blood ; 116(19): 3964-71, 2010 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-20716776

RESUMO

Krox20/EGR2, one of the 4 early growth response genes, is a highly conserved transcription factor implicated in hindbrain development, peripheral nerve myelination, tumor suppression, and monocyte/macrophage cell fate determination. Here, we established a novel role for Krox20 in postnatal skeletal metabolism. Microcomputed tomographic analysis of 4- and 8-week-old mice revealed a low bone mass phenotype (LBM) in both the distal femur and the vertebra of Krox20(+/-) mice. This was attributable to accelerated bone resorption as demonstrated in vivo by increased osteoclast number and serum C-terminal telopeptides, a marker for collagen degradation. Krox20 haploinsufficiency did not reduce bone formation in vivo, nor did it compromise osteoblast differentiation in vitro. In contrast, growth and differentiation were significantly stimulated in preosteoclast cultures derived from Krox20(+/-) splenocytes, suggesting that the LBM is attributable to Krox20 haploinsufficiency in the monocytic lineage. Furthermore, Krox20 silencing in preosteoclasts increased cFms expression and response to macrophage colony-stimulating factor, leading to a cell-autonomous stimulation of cell-cycle progression. Our data indicate that the antimitogenic role of Krox20 in preosteoclasts is the predominant mechanism underlying the LBM phenotype of Krox20-deficient mice. Stimulation of Krox20 expression in preosteoclasts may present a viable therapeutic strategy for high-turnover osteoporosis.


Assuntos
Osso e Ossos/metabolismo , Proteína 2 de Resposta de Crescimento Precoce/deficiência , Monócitos/citologia , Monócitos/metabolismo , Osteoporose/etiologia , Animais , Sequência de Bases , Reabsorção Óssea/etiologia , Reabsorção Óssea/genética , Reabsorção Óssea/metabolismo , Reabsorção Óssea/patologia , Ciclo Celular , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Proliferação de Células , Primers do DNA/genética , Modelos Animais de Doenças , Proteína 2 de Resposta de Crescimento Precoce/genética , Feminino , Haploinsuficiência , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Osteoblastos/metabolismo , Osteoblastos/patologia , Osteoclastos/metabolismo , Osteoclastos/patologia , Osteogênese , Osteoporose/genética , Osteoporose/metabolismo , Osteoporose/patologia , RNA Interferente Pequeno/genética , Transdução de Sinais
6.
J Mater Chem B ; 9(13): 3047-3054, 2021 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-33885666

RESUMO

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.


Assuntos
Eritrócitos/citologia , Sangue Fetal/citologia , Microesferas , Nanoestruturas/química , Diagnóstico Pré-Natal , Feminino , Humanos , Compostos de Manganês/química , Óxidos/química , Gravidez , Dióxido de Silício/química
7.
Mol Cancer ; 9: 258, 2010 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-20863401

RESUMO

BACKGROUND: Prostate cancer (PCa) cells preferentially metastasize to bone at least in part by acquiring osteomimetic properties. Runx2, an osteoblast master transcription factor, is aberrantly expressed in PCa cells, and promotes their metastatic phenotype. The transcriptional programs regulated by Runx2 have been extensively studied during osteoblastogenesis, where it activates or represses target genes in a context-dependent manner. However, little is known about the gene regulatory networks influenced by Runx2 in PCa cells. We therefore investigated genome wide mRNA expression changes in PCa cells in response to Runx2. RESULTS: We engineered a C4-2B PCa sub-line called C4-2B/Rx2 dox, in which Doxycycline (Dox) treatment stimulates Runx2 expression from very low to levels observed in other PCa cells. Transcriptome profiling using whole genome expression array followed by in silico analysis indicated that Runx2 upregulated a multitude of genes with prominent cancer associated functions. They included secreted factors (CSF2, SDF-1), proteolytic enzymes (MMP9, CST7), cytoskeleton modulators (SDC2, Twinfilin, SH3PXD2A), intracellular signaling molecules (DUSP1, SPHK1, RASD1) and transcription factors (Sox9, SNAI2, SMAD3) functioning in epithelium to mesenchyme transition (EMT), tissue invasion, as well as homing and attachment to bone. Consistent with the gene expression data, induction of Runx2 in C4-2B cells enhanced their invasiveness. It also promoted cellular quiescence by blocking the G1/S phase transition during cell cycle progression. Furthermore, the cell cycle block was reversed as Runx2 levels declined after Dox withdrawal. CONCLUSIONS: The effects of Runx2 in C4-2B/Rx2 dox cells, as well as similar observations made by employing LNCaP, 22RV1 and PC3 cells, highlight multiple mechanisms by which Runx2 promotes the metastatic phenotype of PCa cells, including tissue invasion, homing to bone and induction of high bone turnover. Runx2 is therefore an attractive target for the development of novel diagnostic, prognostic and therapeutic approaches to PCa management. Targeting Runx2 may prove more effective than focusing on its individual downstream genes and pathways.


Assuntos
Neoplasias Ósseas/secundário , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Neoplasias da Próstata/complicações , Neoplasias da Próstata/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/genética , Apoptose/genética , Apoptose/fisiologia , Biomarcadores Tumorais/genética , Ciclo Celular/genética , Ciclo Celular/fisiologia , Linhagem Celular Tumoral , Proliferação de Células , Quimiocina CXCL12/genética , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Cistatinas/genética , Fosfatase 1 de Especificidade Dupla/genética , Regulação Neoplásica da Expressão Gênica/genética , Regulação Neoplásica da Expressão Gênica/fisiologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Humanos , Masculino , Metaloproteinase 9 da Matriz/genética , Proteínas dos Microfilamentos/genética , Análise de Sequência com Séries de Oligonucleotídeos , Neoplasias da Próstata/genética , Proteínas Tirosina Quinases/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sindecana-2/genética
8.
J Virol ; 83(1): 37-46, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18945763

RESUMO

Proper folding of newly synthesized viral proteins in the cytoplasm is a prerequisite for the formation of infectious virions. The major capsid protein Vp1 of simian virus 40 forms a series of disulfide-linked intermediates during folding and capsid formation. In addition, we report here that Vp1 is associated with cellular chaperones (HSP70) and a cochaperone (Hsp40) which can be coimmunoprecipitated with Vp1. Studies in vitro demonstrated the ATP-dependent interaction of Vp1 and cellular chaperones. Interestingly, viral cochaperones LT and ST were essential for stable interaction of HSP70 with the core Vp1 pentamer Vp1 (22-303). LT and ST also coimmunoprecipitated with Vp1 in vivo. In addition to these identified (co)chaperones, stable, covalently modified forms of Vp1 were identified for a folding-defective double mutant, C49A-C87A, and may represent a "trapped" assembly intermediate. By a truncation of the carboxyl arm of Vp1 to prevent the Vp1 folding from proceeding beyond pentamers, we detected several apparently modified Vp1 species, some of which were absent in cells transfected with the folding-defective mutant DNA. These results suggest that transient covalent interactions with known or unknown cellular and viral proteins are important in the assembly process.


Assuntos
Antígenos Virais de Tumores/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Vírus 40 dos Símios/fisiologia , Proteínas Estruturais Virais/metabolismo , Montagem de Vírus , Animais , Linhagem Celular , Chlorocebus aethiops , Proteínas de Choque Térmico HSP40/metabolismo , Imunoprecipitação , Mutação Puntual , Ligação Proteica , Deleção de Sequência , Proteínas não Estruturais Virais/metabolismo
9.
ACS Chem Neurosci ; 11(24): 4007-4011, 2020 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-33271013

RESUMO

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.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Peptídeos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Oxalato de Cálcio , Glicina , Humanos , Oxigênio , Valina
10.
J Int Med Res ; 48(6): 300060520929853, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32529876

RESUMO

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.


Assuntos
Encéfalo/patologia , Proteínas de Ligação a DNA/química , Glicina/química , Proteinopatias TDP-43/etiologia , Fatores Etários , Idoso de 80 Anos ou mais , Sequência de Aminoácidos , Proteínas de Ligação a DNA/genética , Glicina/genética , Humanos , Agregados Proteicos/genética , Fatores de Risco , Proteinopatias TDP-43/epidemiologia , Proteinopatias TDP-43/patologia , Valina/química , Valina/genética
11.
Med Hypotheses ; 108: 52-53, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29055401

RESUMO

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.


Assuntos
Carcinoma Hepatocelular/virologia , Vírus da Hepatite B , Hepatite B Crônica/virologia , Cirrose Hepática/virologia , Neoplasias Hepáticas/virologia , Carcinoma Hepatocelular/complicações , Colágeno/metabolismo , Progressão da Doença , Hepatite B Crônica/complicações , Humanos , Ligação de Hidrogênio , Cirrose Hepática/complicações , Neoplasias Hepáticas/complicações , Modelos Biológicos , Modelos Teóricos , Prótons , Transativadores/metabolismo , Proteínas Virais Reguladoras e Acessórias
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA