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1.
Sensors (Basel) ; 24(4)2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38400328

RESUMO

As urban economies flourish and populations become increasingly concentrated, urban surface deformation has emerged as a critical factor in city planning that cannot be overlooked. Surface deformation in urban areas can lead to deformations in structural supports of infrastructure such as road bases and bridges, thereby posing a serious threat to public safety and creating significant safety hazards. Consequently, research focusing on the monitoring of urban surface deformation holds paramount importance. Interferometric synthetic aperture radar (InSAR), as an important means of earth observation, has all-day, wide-range, high-precision, etc., characteristics and is widely used in the field of surface deformation monitoring. However, traditional solitary InSAR techniques are limited in their application scenarios and computational characteristics. Additionally, the manual selection of ground control points (GCPs) is fraught with errors and uncertainties. Permanent scatterers (PS) can maintain high interferometric coherence in man-made building areas, and distributed scatterers (DS) usually show moderate coherence in areas with short vegetation; the combination of DS and PS solves the problem of manually selecting GCPs during track re-flattening and regrading, which affects the monitoring results. In this paper, 45 Sentinel-1B data from 16 February 2019 to 14 December 2021 are used as the data source in the urban area of Horqin District, Tongliao City, Inner Mongolia Autonomous Region, for example. A four-threshold (coherence coefficient threshold, FaSHPS adaptive threshold, amplitude divergence index threshold, and deformation velocity interval) GCPs point screening method for PS-DS, as well as a Small Baseline Subset-Permanent Scatterers-Distributed Scatterers-Interferometric Synthetic Aperture Radar (SBAS-PS-DS-InSAR) method for selecting PS and DS points as ground control points for orbit refinement and re-flattening, are proposed. The surface deformation results obtained using the Small Baseline Subset Interferometric Synthetic Aperture Radar (SBAS-InSAR) and the SBAS-PS-DS-InSAR proposed in this paper were comparatively analysed and verified. The maximum cumulative line-of-sight settlements were -90.78 mm and -83.68 mm, and the maximum cumulative uplifts are 74.94 mm and 97.56 mm, respectively; the maximum annual average line-of-sight settlements are -35.38 mm/y and -30.38 mm/y, and the maximum annual average uplifts are 25.27 mm/y and 27.92 mm/y. The results were evaluated and analysed in terms of correlation, mean absolute error (MAE), and root mean square error (RMSE). The deformation results of the two InSAR methods were evaluated and analysed in terms of correlation, MAE, and RMSE. The errors show that the Pearson correlation coefficients between the vertical settlement results obtained using the SBAS-PS-DS-InSAR method and the GPS monitoring results were closer to 1. The maximum MAE and RMSE were 13.7625 mm and 14.8004 mm, respectively, which are within the acceptable range; this confirms that the monitoring results of the SBAS-PS-DS-InSAR method were better than those of the original SBAS-InSAR method. SBAS-InSAR method, which is valid and reliable. The results show that the surface deformation results obtained using the SBAS-InSAR, SBAS-PS-DS-InSAR, and GPS methods have basically the same settlement locations, extents, distributions, and temporal and spatial settlement patterns. The deformation results obtained using these two InSAR methods correlate well with the GPS monitoring results, and the MAE and RMSE are within acceptable limits. By comparing the deformation information obtained using multiple methods, the surface deformation in urban areas can be better monitored and analysed, and it can also provide scientific references for urban municipal planning and disaster warning.

2.
Sensors (Basel) ; 24(6)2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38544071

RESUMO

The micro-deformation monitoring radar is usually based on Permanent Scatterer (PS) technology to realize deformation inversion. When the region is continuously monitored for a long time, the radar image amplitude and pixel variance will change significantly with time. Therefore, it is difficult to select phase-stable scatterers by conventional amplitude deviation methods, as they can seriously affect the accuracy of deformation inversion. For different regions studied within the same scenario, using a PS selection method based on the same threshold often increases the size of the deformation error. Therefore, this paper proposes a new PS selection method based on the Gaussian Mixture Model (GMM). Firstly, PS candidates (PSCs) are selected based on the pixels' amplitude information. Then, the amplitude deviation index of each PSC is calculated, and each pixel's probability values in different Gaussian distributions are acquired through iterations. Subsequently, the cluster types of pixels with larger probability values are designated as low-amplitude deviation pixels. Finally, the coherence coefficient and phase stability of low-amplitude deviation pixels are calculated. By comparing the probability values of each of the pixels in different Gaussian distributions, the cluster type with the larger probability, such as high-coherence pixels and high-phase stability pixels, is selected and designated as the final PS. Our analysis of the measured data revealed that the proposed method not only increased the number of PSs in the group, but also improved the stability of the number of PSs between groups.

3.
Sensors (Basel) ; 24(8)2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38676251

RESUMO

With the acceleration of urbanisation, urban areas are subject to the combined effects of the accumulation of various natural factors, such as changes in temperature leading to the thermal expansion or contraction of surface materials (rock, soil, etc.) and changes in precipitation and humidity leading to an increase in the self-weight of soil due to the infiltration of water along the cracks or pores in the ground. Therefore, the subsidence of urban areas has now become a serious geological disaster phenomenon. However, the use of traditional neural network prediction models has limitations when examining the causal relationships between time series surface deformation data and multiple influencing factors and when applying multiple influencing factors for predictive analyses. To this end, Sentinel-1A data from March 2017 to February 2023 were used as the data source in this paper, based on time series deformation data acquired using the small baseline subset interferometric synthetic aperture radar (SBAS-InSAR) technique. A sparrow search algorithm-convolutional neural network-long short-term memory (SSA-CNN-LSTM) neural network prediction model was built. The six factors of temperature, humidity, precipitation, and ground temperature at three different depths below the surface (5 cm, 10 cm, and 15 cm) were taken as the input of the model, and the surface deformation data were taken as the output of the neural network model. The correlation between the spatial and temporal evolution characteristics of the ground subsidence in urban areas and various influencing factors was analysed using grey correlation analysis, which proved that these six factors contribute to some extent to the deformation of the urban surface. The main urban area of Hohhot City, Inner Mongolia Autonomous Region, was used as the study area. In order to verify the efficacy of this neural network prediction model, the prediction effects of the multilayer perceptron (MLP), backpropagation (BP), and SSA-CNN-LSTM models were compared and analysed, with the values of the correlation coefficients of the feature points of A1, B1, and C1 being in the range of 0.92, 0.83, and 0.93, respectively. The results show that compared with the traditional MLP and BP neural network models, the SSA-CNN-LSTM model achieves a higher performance in predicting time series surface deformation data in urban areas, which provides new ideas and methods for this area of research.

4.
Mol Biol Rep ; 51(1): 12, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38085373

RESUMO

MicroRNAs (miRNAs) are short noncoding RNAs, approximately 20-24 nucleotides long that negatively regulate gene expression by either inhibiting translation or cleaving complementary mRNA to participate in various biological processes. Accumulating evidence has indicated that miRNAs are widely present in hematological cancers, particularly leukemia, exhibiting either upregulation or downregulation in leukemia patients compared with healthy controls. These miRNAs have a pivotal role in the development, progression and metastasis of leukemia, as well as in the prognosis and/or relapse of patients. miR-22 is one of the abnormally expressed miRNAs in a variety of leukemia diseases, and is considered to be one of the few cancer suppressors. Recent research has demonstrated that miR-22 is involved in the regulation of leukemia cell proliferation, differentiation and apoptosis, and could be a promising biomarker and prognostic indicator for leukemia. Here, we summarize all relevant findings that carry out experimental investigation and clinical analyses, aiming to elucidate the comprehensive implications of miR-22 in various types of leukemia for the development of new therapeutic and prognostic strategies and new drug targets for the treatment of leukemia.


Assuntos
Leucemia , MicroRNAs , Neoplasias , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Leucemia/genética , Neoplasias/genética , Biomarcadores , Diferenciação Celular , Regulação Neoplásica da Expressão Gênica/genética
5.
Mol Biol Rep ; 50(10): 8189-8199, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37563526

RESUMO

BACKGROUND: Placenta accreta spectrum (PAS) is mainly characterized by excessive invasion of the uterine muscle layer accompanied by a large number of foreign blood vessels, leading to severe bleeding during and after delivery. However, the mechanism of excessive invasion of nutrient cells in placenta accreta is currently unclear. METHODS: We performed RNA sequencing of 6 PAS patients and 4 control donors, coupled with Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. The mRNA and protein expression of C-X-C motif ligand 8 (CXCL8) in the placental tissue was measured by qRT‒PCR, immunohistochemical staining and Western blotting. HTR-8/SVneo human villous trophoblast Neo cells were used for in vitro investigation of cell migration and invasion as well as the expression level of CXCL8. RESULTS: A total of 1120 differentially expressed mRNAs were identified in PAS patients. Moreover, GO and KEGG analyses indicated that the differentially expressed mRNAs were most closely associated with immune system processes, biological adhesion and Wnt signaling pathway. The CXCL8 mRNA and protein levels in PAS tissue were significantly higher than those in normal placental tissue. Forced overexpression of CXCL8 significantly increased the migration and invasion of HTR-8/SVneo cells, accompanied by the upregulation of matrix metalloproteinase-2 and matrix metalloproteinase-9 and the downregulation of E-cadherin, which was reversed by knockdown of CXCL8. CONCLUSIONS: CXCL8 was highly expressed in PAS, and knockdown of CXCL8 suppressed the migration and invasion of HTR-8/SVneo cells, suggesting its potential as a diagnostic and therapeutic target for PAS.


Assuntos
Interleucina-8 , Placenta Acreta , Placenta , Feminino , Humanos , Gravidez , Movimento Celular/genética , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Placenta/metabolismo , Placenta Acreta/genética , Placenta Acreta/metabolismo , RNA Mensageiro/metabolismo , Trofoblastos/metabolismo , Interleucina-8/genética , Interleucina-8/metabolismo
6.
Ann Clin Microbiol Antimicrob ; 22(1): 5, 2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36639677

RESUMO

BACKGROUND: Maternal rectovaginal colonization with group B Streptococcus (GBS) or Streptococcus agalactiae is the most common pathway for this disease during the perinatal period. This meta-analysis aimed to summarize existing data regarding maternal colonization, serotype profiles, and antibiotic resistance in China. METHODS: Systematic literature reviews were conducted after searching 6 databases. Meta-analysis was applied to analyze colonization rate, serotype, and antimicrobial susceptibility of GBS clinical isolates in different regions of China. Summary estimates are presented using tables, funnel plots, forest plots, histograms, violin plots, and line plots. RESULTS: The dataset regarding colonization included 52 articles and 195 303 pregnant women. Our estimate for maternal GBS colonization in China was 8.1% (95% confidence interval [CI] 7.2%-8.9%). Serotypes Ia, Ib, III, and V account for 95.9% of identified isolates. Serotype III, which is frequently associated with the hypervirulent clonal complex, accounts for 46.4%. Among the maternal GBS isolates using multilocus sequence typing (MLST), ST19 (25.7%, 289/1126) and ST10 (25.1%, 283/1126) were most common, followed by ST12 (12.4%, 140/1126), ST17 (4.8%, 54/1126), and ST651 (3.7%, 42/1126). GBS was highly resistant to tetracycline (75.1% [95% CI 74.0-76.3%]) and erythromycin (65.4% [95% CI 64.5-66.3%]) and generally susceptible to penicillin, ampicillin, vancomycin, ceftriaxone, and linezolid. Resistance rates of GBS to clindamycin and levofloxacin varied greatly (1.0-99.2% and 10.3-72.9%, respectively). A summary analysis of the bacterial drug resistance reports released by the China Antimicrobial Resistance Surveillance System (CARSS) in the past 5 years showed that the drug resistance rate of GBS to erythromycin, clindamycin, and levofloxacin decreased slowly from 2018 to 2020. However, the resistance rates of GBS to all 3 antibiotics increased slightly in 2021. CONCLUSIONS: The overall colonization rate in China was much lower than the global colonization rate (17.4%). Consistent with many original and review reports in other parts of the world, GBS was highly resistant to tetracycline. However, the resistance of GBS isolates in China to erythromycin and clindamycin was greater than in other countries. This paper provides important epidemiological information, to assist with prevention and treatment of GBS colonization in these women.


Assuntos
Clindamicina , Infecções Estreptocócicas , Feminino , Gravidez , Humanos , Clindamicina/farmacologia , Clindamicina/uso terapêutico , Infecções Estreptocócicas/microbiologia , Levofloxacino/farmacologia , Streptococcus agalactiae , Tipagem de Sequências Multilocus , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Eritromicina/farmacologia , Tetraciclina/farmacologia , Farmacorresistência Bacteriana , China/epidemiologia , Testes de Sensibilidade Microbiana
7.
J Asian Nat Prod Res ; 21(2): 117-122, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29063787

RESUMO

Two new stilbenoids, named 2,3 -dimethoxyl-7-hydroxyl-1,4-phenanthrenedione (1) and 2-methoxyl-3-methyl-7-hydroxyl-9,10-dihydro-1,4-phenanthrenedione (2), together with two known stilbenoids including densiflorol B (3) and ephemeranthoquinone (4), were isolated from aerial parts of Flickingeria fimbriata (Bl.) Hawkes. The structures of two new compounds were elucidated by extensive spectroscopic analysis, including HRESIMS, 1H and 13C NMR, DEPT, HMBC, COSY, HMQC, NOESY. All the compounds were obtained from this genus for the first time. In addition, they all exhibited moderate cytotoxic activities against HepG2 cell lines.


Assuntos
Orchidaceae/química , Componentes Aéreos da Planta/química , Sesquiterpenos/isolamento & purificação , Estilbenos/isolamento & purificação , Medicamentos de Ervas Chinesas , Células Hep G2/efeitos dos fármacos , Humanos , Estrutura Molecular , Sesquiterpenos Policíclicos , Sesquiterpenos/química , Sesquiterpenos/toxicidade , Estilbenos/química , Estilbenos/toxicidade
9.
BMC Genomics ; 18(1): 173, 2017 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-28201982

RESUMO

BACKGROUND: Spinal cord injury (SCI) results in fatal damage and currently has no effective treatment. The pathological mechanisms of SCI remain unclear. In this study, genome-wide transcriptional profiling of spinal cord samples from injured rats at different time points after SCI was performed by RNA-Sequencing (RNA-Seq). The transcriptomes were systematically characterized to identify the critical genes and pathways that are involved in SCI pathology. RESULTS: RNA-Seq results were obtained from total RNA harvested from the spinal cords of sham control rats and rats in the acute, subacute, and chronic phases of SCI (1 day, 6 days and 28 days after injury, respectively; n = 3 in every group). Compared with the sham-control group, the number of differentially expressed genes was 1797 in the acute phase (1223 upregulated and 574 downregulated), 6590 in the subacute phase (3460 upregulated and 3130 downregulated), and 3499 in the chronic phase (1866 upregulated and 1633 downregulated), with an adjusted P-value <0.05 by DESeq. Gene ontology (GO) enrichment analysis showed that differentially expressed genes were most enriched in immune response, MHC protein complex, antigen processing and presentation, translation-related genes, structural constituent of ribosome, ion gated channel activity, small GTPase mediated signal transduction and cytokine and/or chemokine activity. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed that the most enriched pathways included ribosome, antigen processing and presentation, retrograde endocannabinoid signaling, axon guidance, dopaminergic synapses, glutamatergic synapses, GABAergic synapses, TNF, HIF-1, Toll-like receptor, NF-kappa B, NOD-like receptor, cAMP, calcium, oxytocin, Rap1, B cell receptor and chemokine signaling pathway. CONCLUSIONS: This study has not only characterized changes in global gene expression through various stages of SCI progression in rats, but has also systematically identified the critical genes and signaling pathways in SCI pathology. These results will expand our understanding of the complex molecular mechanisms involved in SCI and provide a foundation for future studies of spinal cord tissue damage and repair. The sequence data from this study have been deposited into Sequence Read Archive ( http://www.ncbi.nlm.nih.gov/sra ; accession number PRJNA318311).


Assuntos
Perfilação da Expressão Gênica , Análise de Sequência de RNA , Traumatismos da Medula Espinal/genética , Animais , Feminino , Ontologia Genética , Ratos , Ratos Sprague-Dawley
10.
Zhongguo Zhong Yao Za Zhi ; 42(23): 4593-4597, 2017 Dec.
Artigo em Zh | MEDLINE | ID: mdl-29376257

RESUMO

To provide theoretical basis for the traceability and quality evaluation of edible bird's nests (EBNs), the Cytb sequence was applied to identify the origin of EBNs. A total of 39 experiment samples were collected from Malaysia, Indonesia, Vietnam and Thailand. Genomic DNA was extracted for the PCR reaction. The amplified products were sequenced. 36 sequences were downloaded from Gen Bank including edible nest swiftlet, black nest swiftlet, mascarene swiftlet, pacific swiftlet and germain's swiftlet. MEGA 7.0 was used to analyze the distinction of sequences by the method of calculating the distances in intraspecific and interspecific divergences and constructing NJ and UPMGA phylogenetic tree based on Kimera-2-parameter model. The results showed that 39 samples were from three kinds of EBNs. Interspecific divergences were significantly greater than the intraspecific one. Samples could be successfully distinguished by NJ and UPMGA phylogenetic tree. In conclusion, Cytb sequence could be used to distinguish the origin of EBNs and it is efficient for tracing the origin species of EBNs.


Assuntos
Aves/classificação , Código de Barras de DNA Taxonômico , Animais , DNA , Indonésia , Malásia , Filogenia , Tailândia , Vietnã
11.
J Neurosci Res ; 93(10): 1526-33, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26096572

RESUMO

Local activated macrophages derived from infiltrating monocytes play an important role in the damage and repair process of spinal cord injury (SCI). The present study investigates the dynamic change of classically activated proinflammatory (M1) and alternatively activated anti-inflammatory (M2) cells in a rat model with contusive SCI by flow cytometry (FCM) and immunohistochemistry. The macrophage subsets were immunophenotyped by using antibodies against cluster of differentiation (CD)-68, C-C chemokine receptor type 7 (CCR7), CD163, and arginase 1 (Arg1). The CD68(+) CD163(-) and CD68(+) CCR7(+) cells were determined to be M1 subsets, whereas the CD68(+) CD163(+) and CD68(+) Arg1(+) cell subpopulations represented M2 cells. The subsets of macrophages in the injured spinal cord at 1, 3, 5, 7, 14, and 28 days postinjury (dpi) were examined. In the sham-opened spinal cord, few M1 or M2 cells were found. After SCI, the phenotypes of both M1 and M2 cells were rapidly induced. However, M1 cells were detected and maintained at a high level for up to 28 dpi (the longest time evaluated in this study). In contrast, M2 cells were transiently detected at high levels before 7 dpi and returned to preinjury levels at 14 dpi. These results indicate that M1 cell response is rapidly induced and sustained, whereas M2 induction is transient after SCI in rat. Increasing the fraction of M2 cells and prolonging their residence time in the injured local microenvironment is a promising strategy for the repair of SCI.


Assuntos
Polaridade Celular/fisiologia , Macrófagos/fisiologia , Traumatismos da Medula Espinal/patologia , Animais , Antígenos CD/metabolismo , Arginase/metabolismo , Modelos Animais de Doenças , Feminino , Citometria de Fluxo , Cinética , Macrófagos/classificação , Ratos , Ratos Sprague-Dawley , Receptores CCR7/metabolismo , Fatores de Tempo
12.
Brain Behav Immun ; 45: 157-70, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25476600

RESUMO

Classically activated pro-inflammatory (M1) and alternatively activated anti-inflammatory (M2) macrophages populate the local microenvironment after spinal cord injury (SCI). The former type is neurotoxic while the latter has positive effects on neuroregeneration and is less toxic. In addition, while the M1 macrophage response is rapidly induced and sustained, M2 induction is transient. A promising strategy for the repair of SCI is to increase the fraction of M2 cells and prolong their residence time. This study investigated the effect of M2 macrophages induced from bone marrow-derived macrophages on the local microenvironment and their possible role in neuroprotection after SCI. M2 macrophages produced anti-inflammatory cytokines such as interleukin (IL)-10 and transforming growth factor ß and infiltrated into the injured spinal cord, stimulated M2 and helper T (Th)2 cells, and produced high levels of IL-10 and -13 at the site of injury. M2 cell transfer decreased spinal cord lesion volume and resulted in increased myelination of axons and preservation of neurons. This was accompanied by significant locomotor improvement as revealed by Basso, Beattie and Bresnahan locomotor rating scale, grid walk and footprint analyses. These results indicate that M2 adoptive transfer has beneficial effects for the injured spinal cord, in which the increased number of M2 macrophages causes a shift in the immunological response from Th1- to Th2-dominated through the production of anti-inflammatory cytokines, which in turn induces the polarization of local microglia and/or macrophages to the M2 subtype, and creates a local microenvironment that is conducive to the rescue of residual myelin and neurons and preservation of neuronal function.


Assuntos
Transferência Adotiva , Locomoção , Macrófagos/imunologia , Recuperação de Função Fisiológica/imunologia , Traumatismos da Medula Espinal/imunologia , Animais , Axônios/metabolismo , Axônios/patologia , Feminino , Inflamação , Interleucina-10/genética , Interleucina-10/imunologia , Interleucina-13/genética , Interleucina-13/imunologia , Interleucina-1beta/genética , Interleucina-1beta/imunologia , Interleucina-6/genética , Interleucina-6/imunologia , Macrófagos/transplante , Microglia/imunologia , Microglia/metabolismo , Bainha de Mielina/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/imunologia , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Traumatismos da Medula Espinal/patologia , Traumatismos da Medula Espinal/fisiopatologia , Células Th2/imunologia , Fator de Crescimento Transformador beta/imunologia , Fator de Necrose Tumoral alfa
13.
Food Res Int ; 140: 109875, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33648193

RESUMO

Edible bird's nest (EBN) is built by seven species of Aerodramus and Collocalia (Apodidae), using salivary gland secretion mixed with feathers or grass during the breeding. Its rich nutritional values such as anti-aging activity, immunomodulatory and antioxidant activity make consumers flock to it. Consumers' pursuit, on the one hand, aroused the arrogance of counterfeiters, which eventually leads to food safety problems. On the other hand, it promotes the in-depth studies of EBN in all aspects, such as compositions, biological activities, authenticity identification, quality control, and so on. This paper presented the origins and classifications of EBN and the current situation of EBN industry in detail; reviewed the nutritional compositions, pharmacological actions, identification, inspection and content determination of EBN comprehensively; and prospected the future research directions to provide suggestions for the further study.


Assuntos
Aves , Melhoramento Vegetal , Animais , Antioxidantes , Valor Nutritivo , Saliva
14.
Front Immunol ; 11: 1492, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32765516

RESUMO

Surface antigen one (Sao) protein is a bacterial surface protein identified in the important zoonotic pathogen Streptococcus suis serotype 2 (S. suis 2) during an extensive search for functional proteins. The Sao protein is anchored to the bacterial cell wall by the LPVTG motif and is widely distributed in many S. suis serotypes. In this paper, we present the immunodominant epitope peptide of the Sao protein that is recognized by BALB/c antibodies against the Sao protein: 355SEKQMPSVVNENAVTPEKQMTNKENDNIET384 (location Sao355-384). To determine the core epitope recognized by antibodies, we prepared truncation peptide libraries. Analyses of the immunoreactivity of truncation peptides with anti-Sao355-384 serum revealed that the most immunoreactive sequence was 355SEKQMPSVVNENAVTPEK372 (location Sao355-372). Moreover, we observed that this core epitope also showed good specificity based on the ratio of reactivity with serum from S. suis-positive patients compared to serum from S. suis-negative patients. Our results point to the potential of using the Sao355-372 peptide in diagnostic assays to determine S. suis infection in humans.


Assuntos
Antígenos de Superfície/metabolismo , Proteínas de Bactérias/metabolismo , Zoonoses Bacterianas/imunologia , Parede Celular/metabolismo , Epitopos de Linfócito B/metabolismo , Proteínas de Membrana/metabolismo , Infecções Estreptocócicas/imunologia , Streptococcus suis/fisiologia , Motivos de Aminoácidos/genética , Animais , Anticorpos Antibacterianos/metabolismo , Antígenos de Superfície/genética , Proteínas de Bactérias/genética , Zoonoses Bacterianas/diagnóstico , Epitopos de Linfócito B/genética , Feminino , Humanos , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos BALB C , Biblioteca de Peptídeos , Ligação Proteica , Testes Sorológicos , Infecções Estreptocócicas/diagnóstico
15.
Nat Prod Res ; 34(3): 323-328, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30580630

RESUMO

Chemical investigation of Dendrobium plicatile Lindl resulted in the isolation and identification of one new bibenzyl, 2-chloro-3, 4'-dihydroxy-3',5-dimethoxybibenzyl (1), as well as 15 known stilbenoids. The structures of this new compound was elucidated by extensive spectroscopic analysis, including HRESIMS, 1H and 13C NMR, DEPT, HMBC, COSY, HMQC, NOESY. Compounds 2, 3 and 5 were obtained from this genus for the first time, compounds 8, 10, 13 and 14 were obtained from this plant for the first time. In addition, the new compound exhibited potent cytotoxic activities against the human breast cancer (MDA-MB231) cell line, the hepatocellular carcinoma (HepG2) cell line and the human lung carcinoma (A549) cell line, with IC50 3.41, 3.02, 2.80 µM, respectively.


Assuntos
Dendrobium/química , Componentes Aéreos da Planta/química , Estilbenos/isolamento & purificação , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Citotoxinas/isolamento & purificação , Citotoxinas/farmacologia , Humanos , Concentração Inibidora 50 , Estrutura Molecular , Análise Espectral/métodos , Estilbenos/química , Estilbenos/farmacologia
16.
Nat Prod Res ; 32(8): 933-938, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28880114

RESUMO

A new pair of sesamin-type lignan enantiomers (±)-morifolia A (1a/1b) together with eight known analogues (2-9) were isolated from the fruits of Morinda citrifolia. Their structures were established by spectroscopic data and the absolute configurations of 1a/1b were determined by ECD calculation. All compounds were examined for their inhibitory effects on the nitric oxide (NO) production induced by lipopolysaccharide (LPS) in RAW 264.7 macrophages, and compounds 1a, 1b, 2-4 and 7-9 exhibited pronounced inhibition with IC50 values in the range of 1.97-8.01 (µM, being more active than the positive control, quercetin (IC50 = 15.32 (M).


Assuntos
Dioxóis/química , Lignanas/química , Morinda/química , Animais , Linhagem Celular , Dicroísmo Circular , Frutas/química , Concentração Inibidora 50 , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Espectroscopia de Ressonância Magnética , Camundongos , Estrutura Molecular , Óxido Nítrico/biossíntese , Estereoisomerismo
17.
Nat Prod Res ; 31(13): 1518-1522, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28278646

RESUMO

Chemical investigation of Flickingeria fimbriata (Bl.) Hawkes (Orchidaceae) resulted in the isolation and identification of one new dihydrophenanthrene, 1,2,5,6,7-pentamethoxy-9,10-dihydrophenanthrene (1), together with seven known dihydrophenanthrenes, erianthridin (2), coelonin (3), 4-methoxy-9,10-dihydrophenanthrene-1,2,7-triol (4), lusianthridin (5), ephemeranthol A (6), flavanthridin (7) and hircinol (8), four known phenanthrenes, epheranthol B (9), nudol (10), denthyrsinin (11) and confusarin (12), and one known bibenzyl, batatasin III (13). The structure of the new compound was elucidated by spectroscopic analysis (HRMS, 1D and 2D NMR). All the compounds were isolated from F. fimbriata for the first time except for compounds 5 and 12, and compounds 1, 3, 4, 8, 10, 11 and 13 were obtained from this genus for the first time. Compounds 1-4 showed moderate cytotoxic activity against HepG2 cells.


Assuntos
Orchidaceae/química , Fenóis/isolamento & purificação , Compostos de Bifenilo/isolamento & purificação , Citotoxinas/isolamento & purificação , Citotoxinas/farmacologia , Células Hep G2 , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Fenantrenos/isolamento & purificação , Caules de Planta/química , Estilbenos/isolamento & purificação
18.
Exp Neurol ; 277: 190-201, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26772636

RESUMO

Myelin basic protein (MBP) activated T cells (MBP-T) play an important role in the damage and repair process of the central nervous system (CNS). However, whether these cells play a beneficial or detrimental role is still a matter of debate. Although some studies showed that MBP-T cells are mainly helper T (Th) cells, their subtypes are still not very clear. One possible explanation for MBP-T immunization leading to conflicting results may be the different subtypes of T cells are responsible for distinct effects. In this study, the Th1 and Th2 type MBP-T cells (MBP-Th1 and -Th2) were polarized in vitro, and their effects on the local immune microenvironment and tissue repair of spinal cord injury (SCI) after adoptive immunization were investigated. In MBP-Th1 cell transferred rats, the high levels of pro-inflammatory cells (Th1 cells and M1 macrophages) and cytokines (IFN-γ, TNF-α, -ß, IL-1ß) were detected in the injured spinal cord; however, the anti-inflammatory cells (Th2 cells, regulatory T cells, and M2 macrophages) and cytokines (IL-4, -10, and -13) were found in MBP-Th2 cell transferred animals. MBP-Th2 cell transfer resulted in decreased lesion volume, increased myelination of axons, and preservation of neurons. This was accompanied by significant locomotor improvement. These results indicate that MBP-Th2 adoptive transfer has beneficial effects on the injured spinal cord, in which the increased number of Th2 cells may alter the local microenvironment from one primarily populated by Th1 and M1 cells to another dominated by Th2, Treg, and M2 cells and is conducive for SCI repair.


Assuntos
Proteína Básica da Mielina/metabolismo , Traumatismos da Medula Espinal/patologia , Células Th1/metabolismo , Células Th2/metabolismo , Transferência Adotiva , Análise de Variância , Animais , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Macrófagos/metabolismo , Macrófagos/patologia , Atividade Motora/genética , Transtornos Motores/etiologia , Proteína Básica da Mielina/genética , Proteína Básica da Mielina/imunologia , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Desempenho Psicomotor/fisiologia , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Traumatismos da Medula Espinal/complicações , Acetato de Tetradecanoilforbol/análogos & derivados , Acetato de Tetradecanoilforbol/farmacologia
19.
J Mol Neurosci ; 56(4): 999-1008, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26044662

RESUMO

Our previous study has showed that co-grafted Schwann cells (SCs) promote proliferation and migration of the grafted oligodendrocyte precursor cells (OPCs). However, how the co-grafted SCs affect OPCs has not been clarified. In the present study, we confirmed that SC-induced proliferation and migration of OPCs were mediated by SC-secreted factors using SC-conditioned medium (SCM). Then, we detected several candidate factors, PDGF-AA, FGF-2, and IGF-1, in SCs and SCM, and their receptors in OPCs. Finally, by using the selective inhibitors, the effects of these candidate factors on proliferation and migration of OPCs were examined. Our results showed that SCM-stimulated proliferation and migration of OPCs could be markedly decreased by both AG1295 (the inhibitor of PDGFR) and PD173074 (the inhibitor of FGFR). Together, our study suggests that SCs affect proliferation and migration of OPCs through secreting PDGF-AA and FGF-2. Identity of these molecules not only contributes to understand the mechanism of SC-induced proliferation and migration of OPCs but also provides possible target for treatment of CNS diseases.


Assuntos
Movimento Celular , Proliferação de Células , Fator 2 de Crescimento de Fibroblastos/farmacologia , Células-Tronco Neurais/efeitos dos fármacos , Oligodendroglia/efeitos dos fármacos , Fator de Crescimento Derivado de Plaquetas/farmacologia , Células de Schwann/metabolismo , Animais , Células Cultivadas , Meios de Cultivo Condicionados/farmacologia , Feminino , Fator 2 de Crescimento de Fibroblastos/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Fator de Crescimento Insulin-Like I/farmacologia , Células-Tronco Neurais/citologia , Células-Tronco Neurais/fisiologia , Oligodendroglia/citologia , Oligodendroglia/fisiologia , Fator de Crescimento Derivado de Plaquetas/metabolismo , Ratos , Ratos Sprague-Dawley
20.
Int J Clin Exp Med ; 7(9): 2820-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25356144

RESUMO

OBJECTIVE: Present study is designed to evaluate the effects of preventing pressure ulcer in surgical patients with two types of pressure-relieving mattresses. METHODS: 1074 surgical patients from 12 hospitals in China were divided into A group (static air mattress with repositioning every 2 hours, n = 562) and B group (power pressure air mattress with repositioning every 2 hours, n = 512). The patient was subjected to a pressure-relieving mattress and observed from 0-5 days after surgery. Indications include the Braden scores, hospital-acquired pressure ulcers (HAPU) incidence and stage. RESULTS: The Braden scores between two groups in five days after surgery were no significant (P > 0.05). The incidence of HAPU between two groups in same days also was no significant (1.07% vs. 0.98%, P > 0.05). The incidence of Stage I and stage II pressure ulcers in group A and B were 1.07% (6/562) and 0.98% (5/512), respectively (χ(2) = 0.148, P = 0.882). CONCLUSION: The effects of preventing pressure ulcer in surgical patients with two types of pressure-relieving mattresses are similar, but the protocol by static air mattress with repositioning every 2 hours is benefit when no power.

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