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1.
Comput Biol Med ; 168: 107830, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38086140

RESUMO

Cone-beam computed tomography (CBCT) is generally reconstructed with hundreds of two-dimensional X-Ray projections through the FDK algorithm, and its excessive ionizing radiation of X-Ray may impair patients' health. Two common dose-reduction strategies are to either lower the intensity of X-Ray, i.e., low-intensity CBCT, or reduce the number of projections, i.e., sparse-view CBCT. Existing efforts improve the low-dose CBCT images only under a single dose-reduction strategy. In this paper, we argue that applying the two strategies simultaneously can reduce dose in a gentle manner and avoid the extreme degradation of the projection data in a single dose-reduction strategy, especially under ultra-low-dose situations. Therefore, we develop a Joint Denoising and Interpolating Network (JDINet) in projection domain to improve the CBCT quality with the hybrid low-intensity and sparse-view projections. Specifically, JDINet mainly includes two important components, i.e., denoising module and interpolating module, to respectively suppress the noise caused by the low-intensity strategy and interpolate the missing projections caused by the sparse-view strategy. Because FDK actually utilizes the projection information after ramp-filtering, we develop a filtered structural similarity constraint to help JDINet focus on the reconstruction-required information. Afterward, we employ a Postprocessing Network (PostNet) in the reconstruction domain to refine the CBCT images that are reconstructed with denoised and interpolated projections. In general, a complete CBCT reconstruction framework is built with JDINet, FDK, and PostNet. Experiments demonstrate that our framework decreases RMSE by approximately 8 %, 15 %, and 17 %, respectively, on the 1/8, 1/16, and 1/32 dose data, compared to the latest methods. In conclusion, our learning-based framework can be deeply imbedded into the CBCT systems to promote the development of CBCT. Source code is available at https://github.com/LianyingChao/FusionLowDoseCBCT.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Processamento de Imagem Assistida por Computador , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imagens de Fantasmas , Tomografia Computadorizada de Feixe Cônico/métodos , Algoritmos , Raios X
2.
Genes (Basel) ; 14(7)2023 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-37510357

RESUMO

Some species of the Hyrcanus group are vectors of malaria in China. However, the member species are difficult to identify accurately by morphology. The development of sequencing technologies offers the possibility of further studies based on the complete mitochondrial genome. In this study, samples of mosquitoes of the Hyrcanus group were collected in China between 1997 and 2015. The mitochondrial genomes of ten species of the Hyrcanus group were analyzed, including the structure and base composition, codon usage, secondary structure of tRNA, and base difference sites in protein coding regions. Phylogenetic analyses using maximum-likelihood and Bayesian inference were performed based on mitochondrial genes and complete mitochondrial genomes The mitochondrial genome of 10 Hyrcanus group members ranged from 15,403 bp to 15,475 bp, with an average 78.23% (A + T) content, comprising of 13 PCGs (protein coding genes), 22 tRNAs, and 2 rRNAs. Site differences between some closely related species in the PCGs were small. There were only 36 variable sites between Anopheles sinensis and Anopheles belenrae for a variation ratio of 0.32% in all PCGs. The pairwise interspecies distance based on 13 PCGs was low, with an average of 0.04. A phylogenetic tree constructed with the 13 PCGs was consistent with the known evolutionary relationships. Some phylogenetic trees constructed by single coding regions (such as COI or ND4) or combined coding regions (COI + ND2 + ND4 + ND5 or ND2 + ND4) were consistent with the phylogenetic tree constructed using the 13 PCGs. The phylogenetic trees constructed using some coding genes (COII, ND5, tRNAs, 12S rRNA, and 16S rRNA) differed from the phylogenetic tree constructed using PCGs. The difference in mitochondrial genome sequences between An. sinensis and An. belenrae was very small, corresponding to intraspecies difference, suggesting that the species was in the process of differentiation. The combination of all 13 PCG sequences was demonstrated to be optimal for phylogenetic analysis in closely related species.


Assuntos
Anopheles , Genoma Mitocondrial , Animais , Anopheles/genética , Filogenia , Genoma Mitocondrial/genética , RNA Ribossômico 16S , Teorema de Bayes , Mosquitos Vetores/genética , China
3.
PLoS Negl Trop Dis ; 17(6): e0011399, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37267343

RESUMO

BACKGROUND: Dengue fever is an infectious disease that is imported into Shanghai, China and requires prevention and control measures. Controlling the vector Aedes albopictus through insecticide use is a key approach to dengue control. However, the rapid evolution of insecticide resistance in Ae. albopictus has raised concerns about the failure of dengue control efforts. Knockdown resistance (kdr) caused by point mutations in the voltage-gated sodium channel (VGSC) gene is a primary mechanism of pyrethroid resistance. In this study, we investigated the kdr mutations of Ae. albopictus in Shanghai and evaluated the trend in its evolution. METHODOLOGY/PRINCIPAL FINDINGS: We collected 17 populations of Ae. albopictus from 15 districts in Shanghai in 2020, extracted genomic DNA from individual mosquitoes, and amplified Domain II, III, and IV in VGSC using PCR. Following sequencing, we obtained 658 VGSC sequences. We detected the nonsynonymous mutations V1016G, I1532T, and F1534S/C/I, among which V1016G and F1534C/I were reported in Shanghai for the first time and F1534I was a novel mutant allele in Ae. albopictus. The overall mutation frequency was 84.65%, with individual mutation frequencies ranging from 46.81% to 100%, excluding the Fengxian District population, which had a frequency of 0%. The V1016G and I1532T mutation types accounted for 7.14% and 3.42%, respectively. The mutant allele at codon 1534 accounted for 63.98% of all mutations, including TCC/S (62.77%), TGC/C (1.06%), and ATC/I (0.15%). We identified and classified five intron types in Domain III by length, including A (83 bp, 12.07%), B (68 bp, 87.30%), C (80 bp, 0.16%), D (72 bp, 0.16%), and E (70 bp, 0.31%). Individuals with intron B had a significant mutation tendency at codon 1534 relative to intron A (chi-square test, p < 0.0001). We found no correlation between mutation frequency and the amount of pyrethroid used (Pearson correlation, p = 0.4755). CONCLUSIONS/SIGNIFICANCE: In recent years, kdr mutations in the Ae. albopictus population in Shanghai have rapidly evolved, as evidenced by an increase in mutation types and significantly increased mutation frequency. The F1534I/ATC mutant allele was found to be a novel mutation, F1534C/TGC was reported for the first time in Shanghai, and intron B in Domain III was significantly associated with mutation frequency at codon 1534. Continuous monitoring of resistance changes and strict regulation of insecticide use are required.


Assuntos
Aedes , Dengue , Inseticidas , Piretrinas , Canais de Sódio Disparados por Voltagem , Animais , Humanos , Inseticidas/farmacologia , Aedes/genética , Resistência a Inseticidas/genética , China , Piretrinas/farmacologia , Mutação , Canais de Sódio Disparados por Voltagem/genética , Dengue/prevenção & controle , Mosquitos Vetores/genética
4.
Infect Dis Poverty ; 12(1): 46, 2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37147696

RESUMO

BACKGROUND: Mosquito control is needed to prevent dengue fever, which is mainly spread by Aedes albopictus in China. Application of insecticides is one of the main mosquito control methods; however, this approach can fail due to the knockdown resistance (kdr) gene mutation that causes decreased sensitivity to insecticides in Ae. albopictus. The kdr mutation patterns among different regions in China differ significantly. However, the underlying mechanism and factors that influence kdr mutation remain unclear. To explore the potential influence of genetic background on the development of insecticide resistance in Ae. albopictus, we analyzed the genetic structure of Ae. albopictus populations in China and its correlation with major kdr mutations. METHODS: We collected Ae. albopictus from 17 sites in 11 provinces (municipalities) across China from 2016 to 2021 and extracted the genomic DNA from individual adult mosquitoes. We selected eight microsatellite loci for genotyping, and based on microsatellite scores, we estimated intraspecific genetic diversity, population structure, and effective population size. The association between the intrapopulation genetic variation and F1534 mutation rate was evaluated by the Pearson correlation coefficient. RESULTS: Based on variation analysis of the microsatellite loci of 453 mosquitoes representing 17 populations throughout China, more than 90% of the variation occurred within individuals, whereas only about 9% of the variation occurred among populations, indicating that field populations of Ae. albopictus are highly polymorphic. The northern populations tended to belong to gene pool I (BJFT 60.4%, SXXA 58.4%, SDJN 56.1%, SXYC 46.8%), the eastern populations tended to belong to pool III (SH 49.5%, JZHZ 48.1%), and the southern populations tended to belong to three different gene pools. Moreover, we observed that the greater the fixation index (FST), the lower the wild-type frequency of F1534 of VSGC. CONCLUSIONS: The degree of genetic differentiation among Ae. albopictus populations in China was low. These populations were divided into three gene pools, in which the northern and eastern pools are relatively homogeneous, while the southern gene pool is heterogeneous. The possible correlation between its genetic variations and kdr mutations is also noteworthy.


Assuntos
Aedes , Inseticidas , Piretrinas , Humanos , Animais , Inseticidas/farmacologia , Mutação , China , Resistência a Inseticidas/genética , Estruturas Genéticas
5.
Acta Trop ; 238: 106798, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36529191

RESUMO

The accurate identification of sandfly species is crucial because some species transmit medically significant diseases, including leishmaniasis, bartonellosis and sandfly fever. However, due to the high similarity of the external morphology in sandfly species, identification can only be performed using internal morphological characteristics after dissection, which is time consuming and requires highly experienced staff. Thus, the introduction of suitable molecular markers may solve these identification problems. This study screened suitable DNA barcodes to identify common sandfly species in China. The phlebotomine sandflies were collected from Sichuan, Henan and Hainan Provinces from 2014 to 2016. The species were identified by the morphological characteristics of the pharyngeal armature and spermatheca. The genomic DNA of sandfly was extracted individually, and mitochondrial DNA (mtDNA) cytochrome C oxidase subunit I (COI) and cytochrome B (Cytb) as well as the 18S subunit of ribosomal DNA (rDNA) were amplified using polymerase chain reaction (PCR). Additionally, intraspecific and interspecific differences (p-distance) were calculated to evaluate the feasibility of the three gene fragments as a DNA barcode. The phylogeny trees of all sandfly species in this study were constructed using neighbor joining (NJ) method. Six species were identified by the morphological features, belonging to Phlebotomus and Sergentomyia, as Ph. chinensis s. l., Ph. stantoni, Se. bailyi, Se. iyengari, Se. squamirostris, and Se. squamipleuris. Analysis based on three gene fragments revealed some degree of intraspecific polymorphism among these sandfly species in China. The largest intraspecific variation occurred in Ph. chinensis s. l. (mtDNA COI, p-distance = 0.042; mtDNA Cytb, p-distance = 0.071), but the 18S rDNA fragment showed a small variation (p-distance = 0.005). The ranges of interspecific p-distances for mtDNA COI and mtDNA Cytb were 0.138 - 0.231 and 0.128 - 0.274, respectively. However, the interspecific p-distances of 18S rDNA are relatively low ranging from 0.003 to 0.055. Both mitochondrial COI and Cytb gene fragments are valid molecular identification markers in theses sandfly species. The topological structure of phylogeny trees based on mtDNA COI, mtDNA Cytb and 18S rDNA genes were all consistent with morphological classification. And we also found there were significant intraspecies differences within Ph. chinensis s. l. (0.006-0.071) and Se. bailyi (0.002-0.032) based on mtDNA Cytb gene fragment. Sequence alignment data suggested that Ph. chinensis s. l. from Sichuan should be Ph. sichuanensis, and the sandfly specimen collected from Henan was Ph. chinensis s. s.. There could be cryptic species in Se. bailyi from China.


Assuntos
Phlebotomus , Psychodidae , Animais , China , Citocromos b/genética , Código de Barras de DNA Taxonômico/métodos , DNA Mitocondrial/genética , DNA Ribossômico/genética , Filogenia , Psychodidae/genética
6.
Oxid Med Cell Longev ; 2022: 1274550, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36062196

RESUMO

Traumatic brain injury (TBI) is a serious health issue with a high incidence, high morbidity, and high mortality that poses a large burden on society. Further understanding of the pathophysiology and cell death models induced by TBI may support targeted therapies for TBI patients. Ferroptosis, a model of programmed cell death first defined in 2012, is characterized by iron dyshomeostasis, lipid peroxidation, and glutathione (GSH) depletion. Ferroptosis is distinct from apoptosis, autophagy, pyroptosis, and necroptosis and has been shown to play a role in secondary brain injury and worsen long-term outcomes after TBI. This review systematically describes (1) the regulatory pathways of ferroptosis after TBI, (2) the neurobiological links between ferroptosis and other cell death models, and (3) potential therapies targeting ferroptosis for TBI patients.


Assuntos
Lesões Encefálicas Traumáticas , Ferroptose , Apoptose , Morte Celular , Humanos , Peroxidação de Lipídeos
7.
Clin Rheumatol ; 41(12): 3837-3849, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35925523

RESUMO

INTRODUCTION: Rheumatoid arthritis (RA) is a chronic inflammatory disease involving a variety of immune cells, including adaptive T and B cells and innate lymphoid cells (ILCs). Understanding the pathogenic role of these immune cells in RA provides new insights into the intervention and treatment of RA. METHODS: A total of 86 patients with RA (RA group) and 50 healthy controls (HC) were included in the study. The immune cells of CD4+, CD19+ B, NK, Th17, Treg, ILCs, and their subsets (i.e., ILC1s, ILC2s, and ILC3s) were characterized in peripheral blood mononuclear cells by flow cytometry. Cytokines (i.e., IFN-γ, IL-4, IL-10, IL-17A, IL-22, and IL-33) in sera were detected using ELISA. The above immune cells and cytokines were analyzed in patients with different disease activity status and positive ( +) or negative ( -) rheumatoid factor (RF)/anti-citrullinated protein antibodies (ACPA). RESULTS: Patients with RA had higher percentages of CD4+ T, CD19+ B, Th17, ILC2s, and ILC3s and lower percentages of Treg and ILC1s than HC. Patients with RA had elevated levels of IFN-γ, IL-4, IL-17A, and IL-22 and decreased level of IL-10. Compared with HC, patients with high disease activity had higher percentages of Th17, ILC2s, and ILC3s; lower percentages of ILC1s; and lower level of IL-10. The percentage of Treg cells in remission, low, moderate, and high disease activities decreased, whereas the level of IL-17A increased compared with HC. Furthermore, RF+ or ACPA+ patients exhibited elevated percentages of CD19+ B, ILC2s, and ILC3s and had decreased percentage of ILC1s and Treg cells than HC. The percentage of Th17 cells increased in RF-/ACPA- and RF+/ACPA+ patients. However, the above immune cells between RF or ACPA positive and negative patients were not significantly different. CONCLUSION: Th17, Treg, and ILC subset dysregulations are present in patients with RA but may not be associated with conventionally defined seropositive RF and ACPA. Key Points • Th17, Treg, and ILC subset dysregulations are present in patients with RA but may reflect inflammation rather than specific diseases and stages. • No difference for the distribution of Th17, Treg, and ILC subsets between RF+ and RF- patients and between ACPA+ and ACPA- patients. The screening spectrum of RF and ACPA serology should be expanded to elucidate the role of immune cells in RA pathogenesis.


Assuntos
Artrite Reumatoide , Células Th17 , Humanos , Linfócitos T Reguladores , Interleucina-17 , Imunidade Inata , Interleucina-10 , Leucócitos Mononucleares , Interleucina-4 , Citocinas
8.
Sci Total Environ ; 806(Pt 2): 150674, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34597539

RESUMO

BACKGROUND: With dramatically increasing prevalence, diabetes mellitus has imposed a tremendous toll on individual well-being. Humans are exposed to various environmental chemicals, which have been postulated as underappreciated but potentially modifiable diabetes risk factors. OBJECTIVES: To determine the utility of environmental chemical exposure in predicting diabetes mellitus. METHODS: A total of 8501 eligible participants from NHANES 2005-2016 were randomly assigned to a discovery (N = 5953) set and a validation (N = 2548) set. We applied random forest (RF) and least absolute shrinkage and selection operator (LASSO) regression with 10-fold cross-validation in the discovery set to select features, and built an optimal model to predict diabetes mellitus, blood insulin, fasting plasma glucose (FPG) and 2-h plasma glucose after oral glucose tolerance test (2-h PG after OGTT). RESULTS: The machine learning model using LASSO regression predicted diabetes with an area under the receiver operating characteristics (AUROC) of 0.80 and 0.78 in the discovery set and validation set, respectively. The linear model predicted blood insulin level with an R2 of 0.42 and 0.40 in the discovery set and validation set, respectively. For FPG, the discovery set and validation set yielded an R2 of 0.16 and 0.15, respectively. For 2-h PG after OGTT, the discovery set and validation set yielded an R2 of 0.18 and 0.17, respectively. CONCLUSION: We used environmental chemical exposure, constructed machine learning models and achieved relatively accurate prediction for diabetes, emphasizing the predictive value of widespread environmental chemicals for complicated diseases.


Assuntos
Diabetes Mellitus , Diabetes Mellitus/epidemiologia , Jejum , Humanos , Aprendizado de Máquina , Inquéritos Nutricionais , Curva ROC
9.
Chemosphere ; 287(Pt 4): 132395, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34597628

RESUMO

Glufosinate-ammonium (GLA) is a widely used herbicide with emerging concern over its neural and reproductive toxicity. To uncover potential effects of GLA on male reproductive health in mammals, adult male C57BL/6J mice were administered 0.2 mg/kg·d GLA for 5 weeks. After examination on fertility, testis histology and semen quality in the GLA group, we performed deep sequencing to identify repressive epigenetic marks including DNA methylation and histone modifications (H3K27me3 and H3K9me3), together with mRNA transcript levels in sperm. Then, we integrated multi-omics sequencing data to comprehensively explore GLA-induced epigenetic and transcriptomic alterations. We found no significant difference either on fertility, testis histology or semen quality-related indicators. As for epigenome, the protein level of H3K27me3 was significantly increased in GLA sperm. Next generation sequencing showed alterations of these epigenetic marks and extensive transcription inhibition in sperm. These differential repressive marks were mainly distributed at intergenic regions and introns. According to results by Gene Ontology enrichment analysis, both differentially methylated and expressed genes were mainly enriched in pathways related to synapse organization. Subtle differences in genomic imprinting were also observed between the two groups. These results suggested that GLA predominantly impaired sperm epigenome and transcriptome in mice, with little effect on fertility, testis histology or semen quality. Further studies on human sperm using similar strategies need to be conducted for a better understanding of the male reproductive toxicity of GLA.


Assuntos
Epigenoma , Transcriptoma , Aminobutiratos , Animais , Metilação de DNA , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Saúde Reprodutiva , Análise do Sêmen , Espermatozoides/metabolismo
10.
J Inflamm Res ; 14: 5305-5318, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34703270

RESUMO

PURPOSE: Helminths and their products can regulate immune response and offer new strategies to control and alleviate inflammation, including asthma. We previously found that a peptide named as SJMHE1 from Schistosoma japonicum can suppress asthma in mice. This study mainly investigated the molecular mechanism of SJMHE1 in inhibiting asthma inflammation. METHODS: SJMHE1 was administered to mice with OVA-induced asthma via subcutaneous injection, and its effects were detected by testing the airway inflammation of mice. The Th cell distribution was analyzed by flow cytometry. Th-related transcription factor and cytokine expression in the lungs of mice were analyzed using quantitative real-time PCR (qRT-PCR). The expression of miR-155 and levels of phosphorylated STAT3 and STAT5 were also determined after SJMHE1 treatment in mice by qRT-PCR and Western blot analysis. The in vitro mouse CD4+ T cells were transfected with lentivirus containing overexpressed or inhibited miR-155, and the proportion of Th17, Treg cells, CD4+p-STAT3+, and CD4+p-STAT5+ cells were analyzed by flow cytometry. RESULTS: SJMHE1 ameliorated the airway inflammation of asthmatic mice, upregulated the proportion of Th1 and Treg cells, and the expression of Th1 and Treg-related transcription factor and cytokines. Simultaneously, SJMHE1 treatment reduced the percentage of Th2 and Th17 cells and the expression of Th2 and Th17-related transcription factor and cytokines. SJMHE1 treatment decreased the expression of miR-155 and p-STAT3 but increased p-STAT5 expression. In vitro, the percentage of Th17 and CD4+p-STAT3+ cells increased in CD4+ T cells transfected over-expression of miR-155, but SJMHE1 inhibited the miR-155-mediated increase of Th17 cells. Furthermore, SJMHE1 increased the proportion of Treg and CD4+p-STAT5+ cells after transfected over-expression or inhibition of miR-155. CONCLUSION: SJMHE1 regulated the balance of Th17 and Treg cells by modulating the activation of STAT3 and STAT5 via miR-155 in asthma. SJMHE1 might be a promising treatment for asthma.

11.
Parasit Vectors ; 14(1): 455, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34488863

RESUMO

BACKGROUND: Harnessing helminth-based immunoregulation is a novel therapeutic strategy for many immune dysfunction disorders, including inflammatory bowel diseases (IBDs). We previously identified a small molecule peptide from Schistosoma japonicum and named it SJMHE1. SJMHE1 can suppress delayed-type hypersensitivity, collagen-induced arthritis and asthma in mice. In this study, we assessed the effects of SJMHE1 on dextran sulfate sodium (DSS)-induced acute and chronic colitis. METHODS: Acute and chronic colitis were induced in C57BL/6 mice by DSS, following which the mice were injected with an emulsifier SJMHE1 or phosphate-buffered saline. The mice were then examined for body weight loss, disease activity index, colon length, histopathological changes, cytokine expression and helper T (Th) cell subset distribution. RESULTS: SJMHE1 treatment significantly suppressed DSS-induced acute and chronic colitis, improved disease activity and pathological damage to the colon and modulated the expression of pro-inflammatory and anti-inflammatory cytokines in splenocytes and the colon. In addition, SJMHE1 treatment reduced the percentage of Th1 and Th17 cells and increased the percentage of Th2 and regulatory T (Treg) cells in the splenocytes and mesenteric lymph nodes of mice with acute colitis. Similarly, SJMHE1 treatment upregulated the expression of interleukin-10 (IL-10) mRNA, downregulated the expression of IL-17 mRNA and modulated the Th cell balance in mice with chronic colitis. CONCLUSIONS: Our data show that SJMHE1 provided protection against acute and chronic colitis by restoring the immune balance. As a small molecule, SJMHE1 might be a novel agent for the treatment of IBDs without immunogenicity concerns.


Assuntos
Colite/prevenção & controle , Colo/efeitos dos fármacos , Peptídeos/administração & dosagem , Schistosoma japonicum/química , Schistosoma japonicum/efeitos dos fármacos , Esquistossomose Japônica/imunologia , Esquistossomose Japônica/prevenção & controle , Animais , Colite/induzido quimicamente , Colite/imunologia , Colo/imunologia , Colo/parasitologia , Colo/patologia , Citocinas/genética , Citocinas/imunologia , Sulfato de Dextrana/administração & dosagem , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Peptídeos/imunologia , Schistosoma japonicum/genética , Schistosoma japonicum/imunologia , Células Th1/imunologia , Células Th17/imunologia , Células Th2/imunologia
12.
Front Oncol ; 11: 687871, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34395254

RESUMO

OBJECTIVES: To reveal the mechanisms of the effects of mortalin in hepatocellular carcinoma (HCC) and to identify potential novel chemical inhibitors of mortalin. MATERIALS AND METHODS: For the experiments, three HCC cell lines (HepG2 cells, Hep3B cells, and sorafenib-resistant HuH7 cells) and xenografted nude mice were used. For the clinical analysis, cohorts of 126 patients with HCC and 34 patients with advanced recurrent HCC receiving sorafenib therapy were examined. RESULTS: Mortalin regulated the phosphorylation-modification of cancer-associated proteins and also regulated angiogenesis-related secretome to cause angiogenesis and sorafenib resistance in HCC cells. Two molecular mechanisms were identified. In one, via phosphatidylinositol 3-kinase (PI3K)/Akt signaling, mortalin regulated nuclear factor (NF)-κB and then activated vascular endothelial growth factor (VEGF)/vascular endothelial growth factor receptor (VEGFR)2 and granulocyte-macrophage colony-stimulating factor (GM-CSF), leading to neovascularization. In the other, mortalin regulated PI3K/Akt/ß-catenin and then regulated Bcl-XL and Bcl-2, leading to the antiapoptosis effect of HCC. Treatment of the sorafenib-resistant xenografts with sorafenib in combination with mortalin knockdown facilitated the sorafenib-mediated inhibition of tumor growth and angiogenesis and increased apoptosis. Mortalin was a potential risk factor for HCC, predicting poor prognosis and sorafenib resistance. Finally, we showed that caffeic acid (C9H8O4) could bind to and induce the ubiquitination-mediated degradation of mortalin, which in turn blocked the abovementioned signaling pathways, leading to the inhibition of angiogenesis and the reversal of sorafenib resistance. CONCLUSIONS: Mortalin, which regulates the phosphorylation of cancer-associated proteins, caused angiogenesis and sorafenib resistance, and was a competitive risk factor for HCC. Caffeic acid can therefore be considered a novel chemical inhibitor that targets the action of mortalin and a potential treatment for HCC.

13.
Reprod Toxicol ; 103: 149-158, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34146662

RESUMO

Atrazine is one of the widely used herbicides in the world and most of the current researches on atrazine neurodevelopment toxicity have focused on rodents or zebrafish models in vivo, resulting in relatively high cost, time consumption, and lower translational value to identify its hazard for the developing brain. Major international initiatives have pushed forward to convert the traditional animal-based developmental toxicity tests to in vitro assays using human cells to detect and predict chemical health hazards. In this study, we presented a human neural differentiation model based on human embryonic stem cells (hESC) that can be used to test toxicity at different stages of neural differentiation in vitro. hESC were differentiated into neural stem cells (NSC) and then terminally differentiated towards mixed neurons and glial cells for 21 days. Cell survival, proliferation, cell cycle, apoptosis, and gene expression levels were examined. Our results demonstrated that atrazine inhibited the proliferation of hESC and NSC, and showed different toxic sensitivity on these two kinds of cells. Also, atrazine blocked the NSC cell cycle G1 phase via down-regulating CCND1, CDK2, and CDK4, with no obvious effect on apoptosis. In addition, atrazine curbed EB spontaneous differentiation and NSC-induced neurons and glia cells differentiation. Atrazine altered genes expression levels of PAX6, TUBB3, NCAM1, GFAP, TH, NR4A1, and GRIA1. From the data we obtained, we recognized that the dopaminergic system was not the only target of atrazine neurotoxicity, glutamatergic neurons and astrocytes were also adversely affected.


Assuntos
Atrazina/toxicidade , Herbicidas/toxicidade , Neurônios/efeitos dos fármacos , Animais , Astrócitos , Ciclo Celular , Diferenciação Celular , Linhagem Celular , Células-Tronco Embrionárias , Regulação da Expressão Gênica no Desenvolvimento , Células-Tronco Embrionárias Humanas , Humanos , Células-Tronco Neurais , Neurogênese/efeitos dos fármacos , Síndromes Neurotóxicas , Peixe-Zebra
15.
Front Med (Lausanne) ; 8: 627725, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33681255

RESUMO

Chronic itch is a common distressing symptom of many diseases, which reduced patient's quality of life. The mechanistic study on itch and screening for new anti-itch drugs require the development of new pre-clinical itch animal models. Herein, we established an acute itch model by intradermal (i.d.) injection of low-dose formalin into the neck or cheek in mice. In mice, i.d. injection of formalin (0.1-5%) in the nape of the neck evoked robust scratching behavior in a dose-dependent manner and the dose-response curves showed an inverted "U" shape. I.d. injection of formalin (0.3-0.6%) into the cheek evoked scratching in mice but wiping in rats, while formalin (1.25-5%) induced mixed wiping and scratching behavior in both mice and rats. Further, we found that 0.3% formalin-induced scratching was histamine-independent and significantly attenuated by transient receptor potential ion channel A1 (TRPA1) inhibitor (HC030031) or in TRPA1 knockout (KO) mice, but not affected by transient receptor potential ion channel V1 (TRPV1) inhibitor (capsazepine) or in TRPV1 KO mice. Additionally, 0.3% formalin-induced up-regulation of phosphorylation of extracellular regulated protein kinases (p-ERK) in the dorsal root ganglion (DRG) and scratching were suppressed by intrathecal injection of MEK inhibitor U0126 in mice. Incubation of 0.03% formalin induced the accumulation of intracellular reactive oxygen species (ROS) in the cultured DRG-derived cell line ND7-23, and formalin-induced itch was suppressed by antioxidants in mice. Finally, perfusion of 0.03% formalin induced elevation of intracellular calcium in a subset of primary cultured DRG neurons of mice. Thus, these results indicate that low-dose formalin induced non-histaminergic itch by activation of TRPA1 in mice, which may be employed as a useful acute itch model for screening potential anti-itch drugs.

16.
Int J Biol Sci ; 16(12): 2072-2083, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32549755

RESUMO

Asthma is a complex and heterogeneous inflammatory response characterized by various immune cells, including myeloid-derived suppressor cells (MDSCs) and CD4+ T-cell subsets. However, few studies on MDSC subsets and the association between MDSCs and CD4+ T-cell subsets in asthma are reported. In the present study, we detected CD4+ T cells and MDSC subsets and evaluated the relationship of these cells in mice with ovalbumin-induced asthma. We found that asthmatic mice showed severe airway inflammatory response and inflammatory cell infiltration in the lungs and bronchoalveolar lavage fluid. We also noted increased numbers of Th2, Th17, and MDSCs; decreased proportion of Th1 and Treg cells in the splenocytes and lungs; and increased expression of pro-inflammatory cytokines in splenocytes and lungs. Granulocytic MDSCs (G-MDSCs) and Th17 cells were closely related. Gemcitabine treatment reduced the G-MDSC level and the iNOS expression, alleviated the inflammatory response, and decreased the proportion and number of Th2 and Th17 cells in asthmatic mice. Besides the increase in Th2 and Th17 cells, the findings indicate that G-MDSC elevation plays a crucial role in asthmatic mice.


Assuntos
Asma/induzido quimicamente , Células Supressoras Mieloides/fisiologia , Células Th17/fisiologia , Animais , Citocinas , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Granulócitos , Pulmão/citologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina , Distribuição Aleatória , Baço/citologia , Linfócitos T Reguladores
17.
Cell Death Discov ; 5: 120, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31341646

RESUMO

Sorafenib resistance is one of the main obstacles to the treatment of advanced/recurrent hepatocellular carcinoma (HCC). Here, sorafenib-resistant HCC cells and xenografts in nude mice were used as experimental models. A cohort of patients with advanced recurrent HCC who were receiving sorafenib therapy was used to assess the clinical significance of this therapy. Our data showed that 14-3-3η maintained sorafenib resistance in HCC. An analysis of the underlying molecular mechanisms revealed that 14-3-3η stabilizes hypoxia-inducible factor 1α (HIF-1α) through the inhibition of ubiquitin-dependent proteasome protein degradation, which leads to the maintenance of cancer stem cell (CSC) properties. We further found that microRNA-16 (miR-16) is a competent miRNA that reverses sorafenib resistance by targeting the 3'-UTR of 14-3-3η and thereby inhibits 14-3-3η/HIF-1α/CSC properties. In HCC patients, significant negative correlations were found between the expression of miR-16 and 14-3-3η, HIF-1α, or CSC properties. Further analysis showed that low miR-16 expression but high 14-3-3η expression can prognosticate sorafenib resistance and poor survival. Collectively, our present study indicated that miR-16/14-3-3η is involved in sorafenib resistance in HCC and that these two factors could be potential therapeutic targets and biomarkers for predicting the response to sorafenib treatment.

18.
J Exp Clin Cancer Res ; 37(1): 321, 2018 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-30572915

RESUMO

BACKGROUND: Multi-drug resistance (MDR) is one of the main obstacles for treatment of advanced/recurrent hepatocellular carcinoma (HCC). We have previously identified arsenic trioxide (ATO) as an effective metastasis/angiogenesis inhibitor in HCC. Here, we further found that MDR-HCC cells were more sensitive to ATO. METHODS: The MDR-HCC cells were used as experimental models. Biological functions were investigated using cell transfection, polymerase chain reaction, western blot, southwestern blot, immunostaining, immunoprecipitation plus atomic fluorescence spectrometry, and so on. RESULTS: The MDR-HCC cells underwent high oxidative stress condition, and employed adaptive mechanisms for them to survive; while ATO abolished such mechanisms via targeting the 14-3-3η/nuclear factor kappa B (NF-κB) feedback Loop. Briefly, in MDR cells, the increase of ROS activated NF-κB signaling, which transcriptionally activated 14-3-3η. Meanwhile, the activation of NF-κB can be constitutively maintained by 14-3-3η. As a NF-κB inhibitor, ATO transcriptionally inhibited the 14-3-3η mRNA level. Meanwhile, ATO was also validated to directly bind to 14-3-3η, enhancing the degradation of 14-3-3η protein in an ubiquitination-dependent manner. Knockdown of 14-3-3η reduced the ATO-induced reversal extents of drug resistance in MDR cells. CONCLUSION: 14-3-3η/NF-κB feedback loop plays an important role in maintaining the MDR phenotype in HCC. Moreover, via targeting such feedback loop, ATO could be considered as a potential molecular targeted agent for the treatment of HCC.


Assuntos
Proteínas 14-3-3/metabolismo , Trióxido de Arsênio/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , NF-kappa B/metabolismo , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Retroalimentação Fisiológica , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Transdução de Sinais , Transfecção
19.
Mol Oncol ; 11(10): 1348-1360, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28649742

RESUMO

Chromodomain helicase DNA binding proteins (CHDs) are characterized by N-terminal tandem chromodomains and a central adenosine triphosphate-dependent helicase domain. CHDs govern the cellular machinery's access to DNA, thereby playing critical roles in various cellular processes including transcription, proliferation, and DNA damage repair. Accumulating evidence demonstrates that mutation and dysregulation of CHDs are implicated in the pathogenesis of developmental disorders and cancer. However, we know little about genomic and transcriptomic alterations and the clinical significance of most CHDs in human cancer. We used TCGA and METABRIC datasets to perform integrated genomic and transcriptomic analyses of nine CHD genes in more than 10 000 primary cancer specimens from 32 tumor types, focusing on breast cancers. We identified associations among recurrent copy number alteration, gene expression, clinicopathological features, and patient survival. We found that CHD7 was the most commonly gained/amplified and mutated, whereas CHD3 was the most deleted across the majority of tumor types, including breast cancer. Overexpression of CHD7 was more prevalent in aggressive subtypes of breast cancer and was significantly correlated with high tumor grade and poor prognosis. CHD7 is required to maintain open, accessible chromatin, thus providing fine-tuning of transcriptional regulation of certain classes of genes. We found that CHD7 expression was positively correlated with a small subset of classical oncogenes, notably NRAS, in breast cancer. Knockdown of CHD7 inhibits cell proliferation and decreases gene expression of several CHD7 targets, including NRAS, in breast cancer cell lines. Thus, our results demonstrate the oncogenic potential of CHD7 and its association with poor prognostic parameters in human cancer.


Assuntos
DNA Helicases/genética , Proteínas de Ligação a DNA/genética , Regulação Neoplásica da Expressão Gênica , Mutação , Neoplasias/genética , Transcriptoma , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Feminino , Dosagem de Genes , Genômica , Humanos , Masculino , Neoplasias/patologia , Oncogenes , Prognóstico , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia
20.
Am J Cancer Res ; 7(5): 1213-1226, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28560068

RESUMO

There are 18 lysine deacetylases, also known as histone deacetylases (HDACs), that remove acetyl groups from histone and non-histone proteins, thereby playing critical roles in numerous biological processes. In many human cancers, HDACs are dysregulated through mutation, altered expression, or inappropriate recruitment to certain loci. However, knowledge of the genomic and transcriptomic alterations and the clinical significance of most HDACs in breast cancer remain incomplete. We used TCGA and METABRIC datasets to perform comprehensive, integrated genomic and transcriptomic analyses of 18 HDAC genes in approximately 3000 primary breast cancers and identified associations among recurrent copy number alteration, gene expression, clinicopathological features, and patient survival. We found distinct patterns of copy number alteration and expression for each HDAC in breast cancer subtypes. We demonstrated that HDAC2 and SIRT7 were the most commonly amplified/overexpressed, and SIRT3 was most deleted/underexpressed, particularly in aggressive basal-like breast cancer. Overexpression of HDAC2 was significantly correlated with high tumor grade, positive lymph node status, and poor prognosis. The HDAC inhibitor mocetinostat showed anti-tumor effects in HDAC2-overexpressing basal-like breast cancer lines in vitro. Furthermore, HDAC2 expression was positively correlated with a set of DNA-damage response genes, notably RAD51. We revealed a potential mechanism by which HDAC2 regulates RAD51 expression-by indirect mediation through microRNAs, e.g., miR-182. HDAC inhibitors have emerged as a promising new class of multifunctional anticancer agents. Identifying which breast cancers or patients show HDAC deregulation that contributes to tumor development/progression might enable us to improve target cancer therapy.

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