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1.
Brain ; 147(3): 755-765, 2024 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-37850820

RESUMEN

Recent studies have revealed that glioma-associated mesenchymal stem cells play instrumental roles in tumorigenesis and tumour progression and cannot be ignored as a cellular component of the glioma microenvironment. Nevertheless, the origin of these cells and their roles are poorly understood. The only relevant studies have shown that glioma-associated mesenchymal stem cells play a large role in promoting tumour proliferation, invasion and angiogenesis. This review provides a comprehensive summary of their discovery and definition, origin, differences from other tissue-derived mesenchymal stem cells, spatial distribution, functions and prognostic and therapeutic opportunities to deepen the understanding of these cells and provide new insight into the treatment of glioma.


Asunto(s)
Neoplasias Encefálicas , Glioma , Células Madre Mesenquimatosas , Humanos , Neoplasias Encefálicas/patología , Proliferación Celular , Glioma/patología , Microambiente Tumoral
2.
Curr Microbiol ; 81(3): 72, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38253909

RESUMEN

A Gram-stain-negative, yellow, moist and circular, aerobic, motile, and rod-shaped bacterium, designated YIM 151497T, was isolated from soil sample collected from Blue-Bridge, Weizhou Island, Guangxi province, China. Classification using a polyphasic approach suggested that strain YIM 151497T belonged to the genus Pelagibacterium, and was closely relevant to Pelagibacterium nitratireducens JLT2005T (98.8%), Pelagibacterium halotolerans CGMCC 1.7692T (98.7%), Pelagibacterium lixinzhangensis H64T (98.1%), and Pelagibacterium luteolum CGMCC 1.10267T (97.1%). The growth ranges of temperature, pH, and NaCl were 4-40 â„ƒ, pH 4.0-10.0, and 0-7% NaCl, respectively. It was positive for catalase and oxidase. The primary respiratory quinone was Q-10. The elemental fatty acids were Summed Feature 8 (constituting C18:1ω7c and/or C18:1ω6c), C19:0 cyclo ω8c, C16:0, and C18:1ω7c 11-methyl. The major polar lipids were phosphatidylglycerol, diphosphatidylglycerol, and three unidentified glycolipids. The DNA G+C content based on the complete genome sequence was 60.7 mol%. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) between strain YIM 151497T and species of Pelagibacterium were in the ranges of 73.9-86.3% and 19.7-31.3%, respectively. The Average Amino Acid Identity (AAI) between strain YIM 151497T and species of Pelagibacterium were in the ranges of 68.8-88.8%. On the basis of these data, strain YIM 151497T is considered to represent a novel species of the genus Pelagibacterium with the name of Pelagibacterium flavum sp. nov. Type strain is strain YIM 151497T (= KCTC 49826T = CGMCC 1.61521T = MCCC 1K08053T).


Asunto(s)
Alphaproteobacteria , Cloruro de Sodio , China , ADN , Suelo
3.
Curr Microbiol ; 80(1): 21, 2022 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-36460940

RESUMEN

A Gram-negative coccobacillus, YIM 103518T, isolated from wild elephant feces in Xishuangbanna, Yunnan Province, West China, was characterized and identified using a polyphasic taxonomic approach. The strain was strictly aerobic, non-motile, catalase-positive and oxidase-negative, colonies were round, convex, smooth, and pale yellow. The strain growth at 4-40 ℃ (optimum, 28 ℃), pH 6.0-10.0 (optimum, pH 7.0) and 0-4% NaCl (optimum, 0%) in culture medium YIM 38. The major fatty acids of strain YIM 103518T were summed feature 3 (C16:1 ω6c/C16:1 ω7c), C16:0, and C18:1 ω9c. The predominant ubiquinone was Q-9. The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine and phospholipids. The 16S rRNA gene sequence showed moderate level of similarity with Acinetobacter portensis AC 877T (98.7%), Acinetobacter sichuanensis CCTCC AB 2018118T (97.1%), and Acinetobacter cumulans CCTCC AB 2018119T (97.1%). The G+C content of the genomic DNA was 36.5 mol%. Strain YIM 103518T showed an average nucleotide identity value of 86.6%, 77.3% and 78.5%, a digital DNA-DNA hybridizations value of 31.2%, 21.9% and 23.0% with the type strain of A. portensis, A. sichuanensis and A. cumulans based on draft genome sequences, respectively. The results of the phenotypic, chemotaxonomic and phylogenetic analyses, showed that strain YIM 103518T represents a novel species of the genus Acinetobacter, for which the name Acinetobacter faecalis sp. nov. is proposed. The type strain is YIM 103518T (=CCTCC AB 2019201T = NBRC 114057T).


Asunto(s)
Acinetobacter , Elefantes , Animales , ARN Ribosómico 16S/genética , Filogenia , China , Acinetobacter/genética , Heces
4.
J Digit Imaging ; 35(5): 1101-1110, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35478060

RESUMEN

To visualise the tumours inside the body on a screen, a long and thin tube is inserted with a light source and a camera at the tip to obtain video frames inside organs in endoscopy. However, multiple artefacts exist in these video frames that cause difficulty during the diagnosis of cancers. In this research, deep learning was applied to detect eight kinds of artefacts: specularity, bubbles, saturation, contrast, blood, instrument, blur, and imaging artefacts. Based on transfer learning with pre-trained parameters and fine-tuning, two state-of-the-art methods were applied for detection: faster region-based convolutional neural networks (Faster R-CNN) and EfficientDet. Experiments were implemented on the grand challenge dataset, Endoscopy Artefact Detection and Segmentation (EAD2020). To validate our approach in this study, we used phase I of 2,200 frames and phase II of 331 frames in the original training dataset with ground-truth annotations as training and testing dataset, respectively. Among the tested methods, EfficientDet-D2 achieves a score of 0.2008 (mAPd[Formula: see text]0.6+mIoUd[Formula: see text]0.4) on the dataset that is better than three other baselines: Faster-RCNN, YOLOv3, and RetinaNet, and competitive to the best non-baseline result scored 0.25123 on the leaderboard although our testing was on phase II of 331 frames instead of the original 200 testing frames. Without extra improvement techniques beyond basic neural networks such as test-time augmentation, we showed that a simple baseline could achieve state-of-the-art performance in detecting artefacts in endoscopy. In conclusion, we proposed the combination of EfficientDet-D2 with suitable data augmentation and pre-trained parameters during fine-tuning training to detect the artefacts in endoscopy.


Asunto(s)
Artefactos , Redes Neurales de la Computación , Humanos , Endoscopía , Aprendizaje Automático
5.
J Cell Physiol ; 236(11): 7734-7744, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34061990

RESUMEN

Fibroblast-myofibroblast differentiation (FMD) is a critical cellular phenotype during the occurrence and deterioration of pulmonary fibrosis (PF). FMD can increase with an elevated level of reactive oxygen species (ROS) on fibroblasts under oxidative stress. Thioredoxin-interacting protein (TXNIP) is an α-arrestin family protein that regulates the level of intracellular ROS. Nuclear factor erythroid 2-related factor 2 (Nrf2) can protect against FMD in PF. However, the relationship between Nrf2 and TXNIP in FMD remains elusive. Therefore, we established TGF-ß1-induced FMD in vitro and bleomycin (BLM)-induced mouse PF model in vivo to explore whether the activation of Nrf2 can inhibit TXNIP-mediated FMD in PF. Dimethyl itaconate (DMI) was selected to activate Nrf2. Our results showed that TXNIP was elevated and FMD was aggravated in mice lung tissues after BLM administration compared with the saline group. Inversely, Nrf2 decreased TXNIP expression and alleviated FMD in PF. In vitro, TXNIP overexpression enhanced FMD and increased the level of ROS. In contrast, TXNIP deficiency by small interfering RNA (siRNA) attenuated TGF-ß1-induced FMD and reduced ROS. An increase in ROS by H2 O2 can upregulate TXNIP expression. Moreover, Nrf2 also inhibited TGF-ß1-induced FMD and the increase of ROS, with reducing expression of TXNIP, and the inhibitory effect was better than TXNIP siRNA. These results suggest that activation of Nrf2 by DMI can protect against PF via inhibiting TXNIP expression. Our study may provide new therapeutic targets and treatment approaches for PF.


Asunto(s)
Antifibróticos/farmacología , Proteínas Portadoras/antagonistas & inhibidores , Diferenciación Celular/efectos de los fármacos , Fibroblastos/efectos de los fármacos , Pulmón/efectos de los fármacos , Fibrosis Pulmonar/tratamiento farmacológico , Succinatos/farmacología , Tiorredoxinas/antagonistas & inhibidores , Animales , Bleomicina , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Línea Celular , Modelos Animales de Enfermedad , Fibroblastos/metabolismo , Fibroblastos/patología , Humanos , Pulmón/metabolismo , Pulmón/patología , Masculino , Ratones Endogámicos C57BL , Miofibroblastos/efectos de los fármacos , Miofibroblastos/metabolismo , Miofibroblastos/patología , Factor 2 Relacionado con NF-E2/agonistas , Factor 2 Relacionado con NF-E2/metabolismo , Fibrosis Pulmonar/inducido químicamente , Fibrosis Pulmonar/metabolismo , Fibrosis Pulmonar/patología , Especies Reactivas de Oxígeno/metabolismo , Tiorredoxinas/genética , Tiorredoxinas/metabolismo , Factor de Crecimiento Transformador beta1/farmacología
6.
J Cell Mol Med ; 24(10): 5555-5564, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32270599

RESUMEN

The role of long non-coding RNAs (lncRNAs) in kidney diseases has been gradually discovered in recent years. LINC00963, as an lncRNA, was found to be involved in chronic renal failure. However, the role and molecular mechanisms of LINC00963 engaged in acute kidney injury (AKI) were still unclear. In this study, we established rat AKI models by ischaemia and reperfusion (I/R) treatment. Urea and creatinine levels were determined, and histological features of kidney tissues were examined following HE staining. CCK8 assay was chosen to assess the viability of hypoxia-induced HK-2 cells. Dual-luciferase reporter gene assays were performed to verify the target relationship between LINC00963 and microRNA. The mRNA and protein levels were assayed by RT-qPCR and Western blot, respectively. Annexin V-FITC/PI and TUNEL staining were used to evaluate apoptosis. LINC00963 was highly expressed in the cell and rat models, and miR-128-3p was predicted and then verified as a target gene of LINC00963. Knockdown of LINC00963 reduced acute renal injury both in vitro and in vivo. LINC00963 activated the JAK2/STAT1 pathway to aggravate renal I/R injury. LINC00963 could target miR-128-3p to reduce G1 arrest and apoptosis through JAK2/STAT1 pathway to promote the progression of AKI.


Asunto(s)
Lesión Renal Aguda/genética , Lesión Renal Aguda/metabolismo , Janus Quinasa 2/metabolismo , MicroARNs/genética , ARN Largo no Codificante/genética , Factor de Transcripción STAT1/metabolismo , Lesión Renal Aguda/patología , Animales , Apoptosis/genética , Línea Celular , Técnicas de Inactivación de Genes , Masculino , Ratas
7.
J Transl Med ; 16(1): 9, 2018 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-29351801

RESUMEN

BACKGROUND: Bladder cancer (BCa) is one of the most common cancers in the urinary system among the world. Previous studies suggested that TMEM40 expression level was significantly associated with clinicopathological parameters including histological grade, clinical stage and pT status of bladder cancer. However, the molecular mechanism of TMEM40 in BCa remains poorly understood. METHODS: Real-time quantitative RT-PCR (qRT-PCR) and western blot (WB) were used to examine the expression levels of TMEM40 in BCa tissues, paired non-cancer tissues and cell lines. A series of experiments, including CCK-8, wound healing, flow cytometry, transwell and EdU assays were performed to assess the effects of TMEM40 on cell proliferation, cell cycle and apoptosis, migration and invasion. In addition, tumor growth was evaluated in vivo using a xenogenous subcutaneously implant model. All statistical analyses were executed by using the SPSS 20.0 software. All experimental data from three independent experiments were analyzed by Student's t test and results were expressed as mean ± standard deviation. RESULTS: In this study, we identified the role of TMEM40 in the tumorigenesis of bladder cancer and found that it was upregulated in bladder cancer tissues and cell lines, compared with their normal counterparts. The results demonstrated that effective silence of TMEM40 expression suppressed cell proliferation, blocked G1-to-S cell cycle transition, and inhibited cell migration and invasion in human bladder 5637 and EJ cell lines. Consistently, in vivo data showed that TMEM40 silencing could dramatically decreased tumor growth. Further study revealed that TMEM40 knockdown resulted in accumulation of p53 and p21 protein and decrease of c-MYC and cyclin D1 protein. CONCLUSION: These data suggest that TMEM40 represents a potential oncogene, which exert a crucial role in the proliferation and apoptosis via the p53 signaling pathway in BCa, thus probably serve as a novel candidate biomarker and a potential therapeutic target for patients with BCa.


Asunto(s)
Carcinogénesis/metabolismo , Carcinogénesis/patología , Regulación Neoplásica de la Expresión Génica , Proteínas de la Membrana/genética , Neoplasias de la Vejiga Urinaria/genética , Neoplasias de la Vejiga Urinaria/patología , Apoptosis/genética , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Regulación hacia Abajo/genética , Técnicas de Silenciamiento del Gen , Genes Supresores de Tumor , Vectores Genéticos/metabolismo , Humanos , Proteínas de la Membrana/metabolismo , Invasividad Neoplásica , Oncogenes , ARN Interferente Pequeño/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Regulación hacia Arriba/genética
8.
Gynecol Oncol ; 149(1): 188-197, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29395313

RESUMEN

OBJECTIVE: Recent evidence suggests an important role of Myosin 1b (Myo1b) in the progression of several cancers, including prostate cancer and head and neck squamous cell carcinoma (HNSCC). However, the contribution of Myo1b to cervical cancer (CC) remains elusive. METHODS: Quantitative reverse transcription polymerase chain reaction (qRT-PCR), immunohistochemistry and western blotting assays were used to confirm the expression of Myo1b in CC tissues compared with matched non-tumor tissues and CC cells, and analyze its clinical significance. In vitro, RNA interference (siRNA or shRNA) was used to investigate the biological function and underlying mechanism of Myo1b in cervical carcinogenesis. Furthermore, tumor growth was evaluated in vivo using a xenogenous subcutaneously implant model. RESULTS: Here, for the first time we reported that Myo1b expression was significantly increased in human CC, compared to cervical intraepithelial neoplasia (CIN) and normal cervical tissues and that the upregulation of Myo1b was significantly correlated with FIGO Stage, HPV infection, lymph node metastasis and pathological grade. In vitro, knockdown of Myo1b significantly suppressed proliferation, migration, and invasion of CaSki and SiHa cells, and markedly decreased the MMP1/MMP9 activities. Also, silencing the expression of Myo1b dramatically repressed tumor growth in a mouse xenograft model. Further investigations showed that HPV16 E6 or E7 could enhance the expression of Myo1b via upregulating c-MYC. CONCLUSION: Taken together, our data suggested a potential role of Myo1b in cervical carcinogenesis and tumor progression and provided novel insights into the mechanism of how this factor promotes cell proliferation, migration, and invasion in CC cells.


Asunto(s)
Miosina Tipo I/biosíntesis , Neoplasias del Cuello Uterino/metabolismo , Neoplasias del Cuello Uterino/patología , Animales , Western Blotting , Línea Celular Tumoral , Movimiento Celular/fisiología , Proliferación Celular/fisiología , Progresión de la Enfermedad , Femenino , Xenoinjertos , Humanos , Inmunohistoquímica , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Invasividad Neoplásica , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Displasia del Cuello del Útero/metabolismo , Displasia del Cuello del Útero/patología
9.
Nanomedicine ; 14(4): 1227-1236, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29458214

RESUMEN

Dental pulp stem cells (DPSCs) derived from the human dental pulp tissue have multiple differentiation capabilities, such as osteo/odontogenic differentiation. Therefore, DPSCs are deemed as ideal stem cell sources for tissue regeneration. As new nanomaterials based on DNA, tetrahedral DNA nanostructures (TDNs) have tremendous potential for biomedical applications. Here, the authors aimed to explore the part played by TDNs in proliferation and osteo/odontogenic differentiation of DPSCs, and attempted to investigate if these cellular responses could be driven by activating the canonical Notch signaling pathway. Upon exposure to TDNs, proliferation and osteo/odontogenic differentiation of DPSCs were dramatically enhanced, accompanied by up regulation of Notch signaling. In general, our study suggested that TDNs can significantly promote proliferation and osteo/odontogenic differentiation of DPSCs, and this remarkable discovery can be applied in tissue engineering and regenerative medicine to develop a significant and novel method for bone and dental tissue regeneration.


Asunto(s)
Pulpa Dental/citología , Nanoestructuras/química , Células Madre/citología , Ingeniería de Tejidos/métodos , Adolescente , Adulto , Western Blotting , Diferenciación Celular/fisiología , Proliferación Celular/genética , Proliferación Celular/fisiología , Células Cultivadas , Femenino , Citometría de Flujo , Humanos , Masculino , Odontogénesis/genética , Odontogénesis/fisiología , Transducción de Señal/genética , Transducción de Señal/fisiología , Adulto Joven
10.
Nanomedicine ; 13(5): 1809-1819, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28259801

RESUMEN

Adipose-derived stem cells (ADSCs) are considered to be ideal stem cell sources for bone regeneration owing to their ability to differentiate into osteo-like cells. Therefore, they have attracted increasing attention in recent years. Tetrahedral DNA nanostructures (TDNs), a new type of DNA-based biomaterials, have shown great potential for biomedical applications. In the present work, we aimed to investigate the role played by TDNs in osteogenic differentiation and proliferation of ADSCs and tried to explore if the canonical Wnt signal pathway could be the vital biological mechanism driving these cellular responses. Upon exposure to TDNs, ADSCs proliferation and osteogenic differentiation were significantly enhanced, accompanied by the up-regulation of genes correlated with the Wnt/ß-catenin pathway. In conclusion, our results indicate that TDNs are crucial regulators of the increase in osteogenic potential and ADSCs proliferation, and this noteworthy discovery could provide a promising novel approach toward ADSCs-based bone defect regeneration.


Asunto(s)
ADN , Nanoestructuras , Osteogénesis , Vía de Señalización Wnt , Animales , Diferenciación Celular , Femenino , Humanos , Células Madre Mesenquimatosas , Ratas Sprague-Dawley , beta Catenina
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