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1.
Neoplasma ; 70(4): 500-513, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37789776

RESUMO

Long noncoding RNAs (lncRNAs) play important roles in the progression of human cancer. It is reported that lncRNA plasmacytoma variant translocation 1 (PVT1) is involved in colorectal cancer (CRC), however, the underlying mechanism remains to be explored deeply, especially by in vivo models. In the present study, bioinformatics analysis showed that the expression level of PVT1 was upregulated in CRC tissues and highly associated with poor prognosis of CRC patients. In cultured CRC cells, knockdown of PVT1 inhibited cell proliferation and migration of CRC cells, while overexpression of PVT1 promoted the progression of CRC cells. In zebrafish xenografts, the silencing of PVT1 also suppressed the growth and metastasis of CRC cells. For mechanism studies, the binding relationships among PVT1, miR-24-3p, and Neuropilin 1 (NRP1) were predicted by starBase firstly. The luciferase reporter assays verified that PVT1 and NRP1 could bind with miR-24-3p directly. Further studies showed miR-24-3p negatively regulated the progression of CRC cells, the inhibition of miR-24-3p counteracted the repression effects of CRC progression when knocking down PVT1. In addition, the expression of NRP1 was regulated by PVT1, and NRP1 overexpression could partially rescue the inhibition effects of CRC progression when knocking down PVT1 in vitro and in vivo. Our study reveals that PVT1 promotes the proliferation and metastasis of CRC via regulating the miR-24-3p/NRP1 axis, which provides a prognosis biomarker and a potential therapeutic target for CRC patients.


Assuntos
Neoplasias Colorretais , MicroRNAs , RNA Longo não Codificante , Animais , Humanos , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica , Xenoenxertos , MicroRNAs/genética , MicroRNAs/metabolismo , Neuropilina-1/genética , Prognóstico , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/metabolismo
2.
Int J Mol Sci ; 24(5)2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36901925

RESUMO

Phytoplasmas are uncultivable, phloem-limited, phytopathogenic bacteria that represent a major threat to agriculture worldwide. Phytoplasma membrane proteins are in direct contact with hosts and presumably play a crucial role in phytoplasma spread within the plant as well as by the insect vector. Three highly abundant types of immunodominant membrane proteins (IDP) have been identified within the phytoplasmas: immunodominant membrane protein (Imp), immunodominant membrane protein A (IdpA), and antigenic membrane protein (Amp). Although recent results indicate that Amp is involved in host specificity by interacting with host proteins such as actin, little is known about the pathogenicity of IDP in plants. In this study, we identified an antigenic membrane protein (Amp) of rice orange leaf phytoplasma (ROLP), which interacts with the actin of its vector. In addition, we generated Amp-transgenic lines of rice and expressed Amp in tobacco leaves by the potato virus X (PVX) expression system. Our results showed that the Amp of ROLP can induce the accumulation of ROLP and PVX in rice and tobacco plants, respectively. Although several studies have reported interactions between major phytoplasma antigenic membrane protein (Amp) and insect vector proteins, this example demonstrates that Amp protein can not only interact with the actin protein of its insect vector but can also directly inhibit host defense responses to promote the infection. The function of ROLP Amp provides new insights into the phytoplasma-host interaction.


Assuntos
Oryza , Phytoplasma , Actinas/metabolismo , Phytoplasma/metabolismo , Oryza/metabolismo , Proteínas de Membrana/metabolismo , Virulência , Plantas/metabolismo , Nicotiana/metabolismo , Folhas de Planta/metabolismo , Doenças das Plantas/microbiologia
3.
IEEE Trans Image Process ; 31: 7006-7019, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36322492

RESUMO

Quantization is a promising technique to reduce the computation and storage costs of DNNs. Low-bit ( ≤ 8 bits) precision training remains an open problem due to the difficulty of gradient quantization. In this paper, we find two long-standing misunderstandings of the bias of gradient quantization noise. First, the large bias of gradient quantization noise, instead of the variance, is the key factor of training accuracy loss. Second, the widely used stochastic rounding cannot solve the training crash problem caused by the gradient quantization bias in practice. Moreover, we find that the asymmetric distribution of gradients causes a large bias of gradient quantization noise. Based on our findings, we propose a novel adaptive piecewise quantization method to effectively limit the bias of gradient quantization noise. Accordingly, we propose a new data format, Piecewise Fixed Point (PWF), to present data after quantization. We apply our method to different applications including image classification, machine translation, optical character recognition, and text classification. We achieve approximately 1.9 âˆ¼ 3.5× speedup compared with full precision training with an accuracy loss of less than 0.5%. To the best of our knowledge, this is the first work to quantize gradients of all layers to 8 bits in both large-scale CNN and RNN training with negligible accuracy loss.

4.
J Oncol ; 2022: 4689396, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36111241

RESUMO

Background: The role of N6-methyladenosine long noncoding RNAs (lncRNAs) in colorectal cancer (CRC) is elusive. Materials and Methods: We identified m6A-associated lncRNAs by using the data gathered from The Cancer Genome Atlas (TCGA) and stratified CRC patients into different subgroups. Cox regression analysis was performed to construct an m6A-associated lncRNA signature. The role of this signature in the immune microenvironment and prognosis was dissected subsequently. Finally, a gene set enrichment analysis (GSEA) was conducted to predict the possible mechanisms based on the signature. Results: Three m6A-associated clusters were constructed from 866 differentially expressed lncRNAs. Cluster 2 had poor prognosis and low immune cell infiltration. An m6A-associated lncRNA signature consisting of 14 lncRNAs was constructed and recognized as an independent prognostic indicator of CRC by using survival analysis and receiver operating characteristic (ROC) curves. The clinical features and immune cell infiltration status were significantly different in patients stratified by the risk score. Furthermore, GSEA showed that the P53 pathway and natural killer cell-mediated cytotoxicity were more enriched in the low-risk group. Conclusion: Our data revealed that m6A-associated lncRNAs could be potential prognostic indicators of immunogenicity in CRC.

5.
Front Bioeng Biotechnol ; 9: 642502, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34513803

RESUMO

The etiology of lumbocrural pain is tightly concerned with intervertebral disk degeneration (IDD). Bone mesenchymal stem cell (BMSC)-based therapy bears potentials for IDD treatment. The properties of microRNA (miRNA)-modified BMSCs may be altered. This study investigated the role and mechanism of BMSCs promoting extracellular matrix (ECM) remodeling of degenerated nucleus pulposus cells (NPCs) via the miR-101-3p/EIF4G2 axis. NPCs were collected from patients with IDD and lumbar vertebral fracture (LVF). The expressions of miR-101-3p and ECM-related proteins, Collagen-I (Col-I) and Collagen-II (Col-II), were detected using the reverse transcription-quantitative polymerase chain reaction. The expressions of Col-I and Col-II, major non-collagenous component Aggrecan, and major catabolic factor Matrix metalloproteinase-13 (MMP-13) were detected using Western blotting. BMSCs were cocultured with degenerated NPCs from patients with IDD. Viability and apoptosis of NPCs were measured using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and flow cytometry. After the degenerated NPCs were transfected with the miR-101-3p inhibitor, the expressions of ECM-related proteins, cell viability, and apoptosis were detected. The targeting relationship between miR-101-3p and EIF4G2 was verified. Functional rescue experiments verified the effects of miR-101-3p and EIF4G2 on ECM remodeling of NPCs. Compared with the NPCs of patients with LVF, the degenerated NPCs of patients with IDD showed downregulated miR-101-3p, Col-II, and Aggrecan expressions and upregulated MMP-13 and Col-I expressions. BMSCs increased the expressions of miR-101-3p, Aggrecan, and Col-II, and decreased the expressions of MMP-13 and Col-I in degenerated NPCs. BMSCs enhanced NPC viability and repressed apoptosis. Downregulation of miR-101-3p suppressed the promoting effect of BMSCs on ECM remodeling. miR-101-3p targeted EIF4G2. Downregulation of EIF4G2 reversed the inhibiting effect of the miR-101-3p inhibitor on ECM remodeling. In conclusion, BMSCs increased the miR-101-3p expression in degenerated NPCs to target EIF4G2, thus promoting the ECM remodeling of NPCs.

6.
Acta cir. bras ; 33(12): 1052-1060, Dec. 2018. graf
Artigo em Inglês | LILACS | ID: biblio-973489

RESUMO

Abstract Purpose: To establish a method for the preparation of zoledronate liposome and to observe its effect on inducing the apoptosis of rat liver Kupffer cells. Methods: Zoledronate was encapsulated in liposomes, and then the entrapment rate was detected on a spectrophotometer. The prepared Zoledronate liposome (0.01 mg/mL) was injected into the tail vein of SD rats. Three days later, the number of Kupffer cells (CD68 positive) in rat liver tissue was detected by immunohistochemistry. Flow cytometry was used to detect the apoptosis rate of the isolated liver Kupffer cell cultured in vitro. Results: The entrapment rate of Zoledronate was 43.4±7.8%. Immunohistochemistry revealed that the number of Kupffer cells was 19.3±2.1 in PBS group and 5.5±1.7 in Zoledronate liposome group, with a significant difference (P<0.05). The apoptosis rate of Kupffer cells was 4.1±0.8% in PBS group, while it was 9±2.2% and 23.3±5.9% in Zoledronate liposomes groups with different concentrations of Zoledronate liposome (P<0.05). Conclusions: Zoledronate liposomes can effectively induce the apoptosis of Kupffer cells in vivo and in vitro, and the apoptosis rate is related to the concentration of Zoledronate liposome. To establish a rat liver Kupffer cell apoptosis model can provide a new means for further study on Kupffer cell function.


Assuntos
Animais , Masculino , Apoptose/efeitos dos fármacos , Ácido Zoledrônico/farmacologia , Células de Kupffer/efeitos dos fármacos , Fígado/citologia , Imuno-Histoquímica , Distribuição Aleatória , Contagem de Células , Reprodutibilidade dos Testes , Resultado do Tratamento , Ratos Sprague-Dawley , Composição de Medicamentos/métodos , Citometria de Fluxo , Ácido Zoledrônico/administração & dosagem , Ácido Zoledrônico/síntese química , Lipossomos/síntese química
7.
Acta Cir Bras ; 33(12): 1052-1060, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30624510

RESUMO

PURPOSE: To establish a method for the preparation of zoledronate liposome and to observe its effect on inducing the apoptosis of rat liver Kupffer cells. METHODS: Zoledronate was encapsulated in liposomes, and then the entrapment rate was detected on a spectrophotometer. The prepared Zoledronate liposome (0.01 mg/mL) was injected into the tail vein of SD rats. Three days later, the number of Kupffer cells (CD68 positive) in rat liver tissue was detected by immunohistochemistry. Flow cytometry was used to detect the apoptosis rate of the isolated liver Kupffer cell cultured in vitro. RESULTS: The entrapment rate of Zoledronate was 43.4±7.8%. Immunohistochemistry revealed that the number of Kupffer cells was 19.3±2.1 in PBS group and 5.5±1.7 in Zoledronate liposome group, with a significant difference (P<0.05). The apoptosis rate of Kupffer cells was 4.1±0.8% in PBS group, while it was 9±2.2% and 23.3±5.9% in Zoledronate liposomes groups with different concentrations of Zoledronate liposome (P<0.05). CONCLUSIONS: Zoledronate liposomes can effectively induce the apoptosis of Kupffer cells in vivo and in vitro, and the apoptosis rate is related to the concentration of Zoledronate liposome. To establish a rat liver Kupffer cell apoptosis model can provide a new means for further study on Kupffer cell function.


Assuntos
Apoptose/efeitos dos fármacos , Células de Kupffer/efeitos dos fármacos , Fígado/citologia , Ácido Zoledrônico/farmacologia , Animais , Contagem de Células , Composição de Medicamentos/métodos , Citometria de Fluxo , Imuno-Histoquímica , Lipossomos/síntese química , Masculino , Distribuição Aleatória , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Resultado do Tratamento , Ácido Zoledrônico/administração & dosagem , Ácido Zoledrônico/síntese química
8.
Comput Biol Chem ; 65: 16-20, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27694041

RESUMO

OBJECTIVE: This paper aimed to investigate ego modules for TGFß3-induced chondrogenesis in mesenchymal stem cells (MSCs) using ego network algorithm. METHODS: The ego network algorithm comprised three parts, extracting differential expression network (DEN) based on gene expression data and protein-protein interaction (PPI) data; exploring ego genes by reweighting DEN; and searching ego modules by ego gene expansions. Subsequently, permutation test was carried out to evaluate the statistical significance of the ego modules. Finally, pathway enrichment analysis was conducted to investigate ego pathways enriched by the ego modules. RESULTS: A total of 15 ego genes were obtained from the DEN, such as PSMA4, HNRNPM and WDR77. Starting with each ego genes, 15 candidate modules were gained. When setting the thresholds of the area under the receiver operating characteristics curve (AUC) ≥0.9 and gene size ≥4, three ego modules (Module 3, Module 8 and Module 14) were identified, and all of them had statistical significances between normal and TGFß3-induced chondrogenesis in MSCs. By mapping module genes to confirmed pathway database, their ego pathways were detected, Cdc20:Phospho-APC/C mediated degradation of Cyclin A for Module 3, Mitotic G1-G1/S phases for Module 8, and mRNA Splicing for Module 14. CONCLUSIONS: We have successfully identified three ego modules, evaluated their statistical significances and investigated their functional enriched ego pathways. The findings might provide potential biomarkers and give great insights to reveal molecular mechanism underlying this process.


Assuntos
Condrogênese/fisiologia , Células-Tronco Mesenquimais/citologia , Fator de Crescimento Transformador beta3/fisiologia , Perfilação da Expressão Gênica , Humanos
9.
IEEE Trans Image Process ; 25(3): 1033-46, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26780785

RESUMO

We present a deep learning strategy to fuse multiple semantic cues for complex event recognition. In particular, we tackle the recognition task by answering how to jointly analyze human actions (who is doing what), objects (what), and scenes (where). First, each type of semantic features (e.g., human action trajectories) is fed into a corresponding multi-layer feature abstraction pathway, followed by a fusion layer connecting all the different pathways. Second, the correlations of how the semantic cues interacting with each other are learned in an unsupervised cross-modality autoencoder fashion. Finally, by fine-tuning a large-margin objective deployed on this deep architecture, we are able to answer the question on how the semantic cues of who, what, and where compose a complex event. As compared with the traditional feature fusion methods (e.g., various early or late strategies), our method jointly learns the essential higher level features that are most effective for fusion and recognition. We perform extensive experiments on two real-world complex event video benchmarks, MED'11 and CCV, and demonstrate that our method outperforms the best published results by 21% and 11%, respectively, on an event recognition task.

10.
Cell Physiol Biochem ; 35(3): 1125-36, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25766525

RESUMO

BACKGROUND/AIMS: Rheumatoid arthritis (RA) is a systemic chronic inflammatory disease characterised by prominent synoviocyte hyperplasia and a potential imbalance between the growth and death of fibroblast-like synoviocytes (FLS). Mitomycin C (MMC) has previously been demonstrated to inhibit fibroblast proliferation and to induce fibroblast apoptosis. However, the effects of MMC on the proliferation and apoptosis of human RA FLS and the potential mechanisms underlying its effects remain unknown. METHODS: Cell viability was determined using the Cell Counting Kit-8 assay. Apoptotic cell death was analysed via Annexin V-FITC/PI double staining and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labelling. The production of intracellular reactive oxygen species (ROS) was assessed via flow cytometry, and the changes in mitochondrial membrane potential (ΔΨm) were visualized based on JC-1 staining via fluorescence microscopy. The expression of apoptosis-related proteins was determined via Western blot. RESULTS: Treatment with MMC significantly reduced cell viability and induced apoptosis in RA FLS. Furthermore, MMC exposure was found to stimulate the production of ROS and to disrupt the ΔΨm compared to the control treatment. Moreover, MMC increased the release of mitochondrial cytochrome c, the ratio of Bax/Bcl-2, the activation of caspase-9 and caspase-3, and the subsequent cleavage of poly(ADP-ribose) polymerase. CONCLUSION: Our findings suggest that MMC inhibits cell proliferation and induces apoptosis in RA FLS, and the mechanism underlying this MMC-induced apoptosis may involve a mitochondrial signalling pathway.


Assuntos
Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/metabolismo , Mitocôndrias/metabolismo , Mitomicina/administração & dosagem , Apoptose/efeitos dos fármacos , Artrite Reumatoide/patologia , Contagem de Células , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/patologia , Expressão Gênica/efeitos dos fármacos , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/patologia , Proteínas Mitocondriais/biossíntese , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Líquido Sinovial/efeitos dos fármacos , Líquido Sinovial/metabolismo
11.
Eur J Drug Metab Pharmacokinet ; 40(4): 481-4, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25216634

RESUMO

Herb-drug interaction strongly limits the clinical utilization of herbs and drugs. Irinotecan-induced diarrhea is closely related with the UDP-glucuronosyltransferase 1A1-catalyzed glucuronidation of SN-38 which has been widely regarded to be the toxic substance basis of irinotecan. The present study aims to determine the influence of herbal component psoralidin toward the toxicity of irinotecan. In vitro inhibition potential of psoralidin toward the glucuronidation of SN-38 was firstly investigated using human intestinal microsomes incubation system. Dose-dependent inhibition of psoralidin toward SN-38 glucuronidation was observed. Furthermore, Dixon plot showed that the intersection point was located in the second quadrant, indicating the competitive inhibition of psoralidin toward the glucuronidation of SN-38. Through the data fitting using competitive inhibition fitting equation, the inhibition kinetic parameter (K i) was calculated to be 5.8 µM. The translation of these in vitro data into the in vivo situation showed that pre-treatment with psoralidin significantly increased the toxicity of irinotecan, as indicated by the increased body weight loss and more severe colon histology damage. All these data indicated the herb-drug interaction between irinotecan and psoralidin-containing herbs.


Assuntos
Benzofuranos/metabolismo , Camptotecina/análogos & derivados , Colo/metabolismo , Cumarínicos/metabolismo , Interações Ervas-Drogas/fisiologia , Animais , Benzofuranos/farmacologia , Camptotecina/metabolismo , Camptotecina/farmacologia , Colo/efeitos dos fármacos , Cumarínicos/farmacologia , Relação Dose-Resposta a Droga , Humanos , Irinotecano , Masculino , Camundongos , Camundongos da Linhagem 129
12.
Eur J Orthop Surg Traumatol ; 24(1): 23-7, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23412248

RESUMO

The aim of this study was to evaluate the clinical outcomes of the reformed lumbar microdiscectomy preserving more ligamentum flavum than the traditional microdiscectomy does. A prospective, randomized, controlled clinical study was conducted. Patients with unilateral lumbar disc herniation were randomly divided into two groups. The control group underwent traditional lumbar microdiscectomy, and the test group patients underwent the same procedure but with a curved incision of the lumbodorsal fascia and with more preservation of the ligamentum flavum. Visual analogue scale (VAS) scores and Oswestry scale scores were used to appraise the outcomes. Both groups' clinical parameters were significantly improved after the operation. The VAS scores in the test group showed a less intensity than that in the control group at 3 days, 12 weeks after the operation (P < 0.05), while at 1 year, showed no significant difference. Both groups' postoperative leg pain was significantly relieved (P < 0.05). The VAS scores for leg pain had no significant difference between the two groups at any testing time point after the surgery (P > 0.05). The Oswestry scale scores showed a better lumbar function state in the test group than that in the control group at 12 weeks and 1 year after the operation (P < 0.05). In both groups, there was no patient who had a lumbar disc reherniation. Preserving more ligamentum flavum is helpful to improve the clinical outcomes, and this improvement maybe resulted from the prevention of the fibrosis-related complication and the stability of the spine.


Assuntos
Discotomia/métodos , Deslocamento do Disco Intervertebral/cirurgia , Ligamento Amarelo/cirurgia , Vértebras Lombares/cirurgia , Microcirurgia/métodos , Dor Pós-Operatória/etiologia , Adulto , Avaliação da Deficiência , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento , Adulto Jovem
13.
Eur J Pharmacol ; 674(1): 7-12, 2012 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-22056834

RESUMO

The aim of this study was to investigate the effects of topical application mitomycin-C (MMC) on wound healing after laminectomy. 60 adult male SD rats were equally and randomly divided into five groups. Laminectomy was performed at the level of L1 in all rats. After hemostasis was achieved, cotton pads soaked with saline and MMC (0.1mg/ml, 0.3mg/ml, 0.5mg/ml and 0.7mg/ml) were directly subjected to the exposed dura for 5min in each group. Two weeks after laminectomy all the rats were killed. The vertebral column including the back scar tissue and muscles was obtained to make paraffin sections. The hematoxylin-eosin staining and Masson staining were performed with the obtained paraffin sections. The number of the fibroblast and the capillary density were counted by the hematoxylin-eosin staining slice. The extent of epidural fibrosis and the expression of vascular endothelial growth factor (VEGF) were evaluated by the immunohistochemical slice through a computer image analysis system. Our data showed that the number of fibroblast, capillary density and fibrotic tissue in the 0.5 and 0.7mg/ml MMC groups was significantly lower than the control, 0.1 and 0.3mg/ml MMC groups; while the expression of VEGF in control and 0.1mg/ml MMC groups was notably higher than 0.3, 0.5 and 0.7mg/ml MMC groups. Topical application of MMC above the concentration of 0.3mg/ml could affect all steps of the wound healing process via inhibiting the angiogenesis and fibroblast proliferation, thus delayed the wound healing after laminectomy.


Assuntos
Antibacterianos/administração & dosagem , Antibacterianos/farmacologia , Laminectomia/efeitos adversos , Mitomicina/administração & dosagem , Mitomicina/farmacologia , Cicatrização/efeitos dos fármacos , Administração Tópica , Animais , Vasos Sanguíneos/efeitos dos fármacos , Vasos Sanguíneos/patologia , Contagem de Células , Fibroblastos/efeitos dos fármacos , Fibroblastos/patologia , Fibrose , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-Dawley , Fator A de Crescimento do Endotélio Vascular/metabolismo
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