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1.
Stem Cells ; 41(4): 368-383, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-36682034

RESUMO

Diabetic kidney disease (DKD) is the leading cause of end-stage renal disease worldwide. Exosomes (Exo) derived from human umbilical cord mesenchymal stem cells (HUC-MSCs) have been demonstrated to be an effective therapy for DKD, but the underlying mechanisms of this action remain poorly defined. We investigated the association of DKD with inflammasome activation and the pathophysiological relevance of Exo-mediated inflammation relief as well as damage repair in this progression. We co-cultured podocytes and HUC-MSCs derived Exo (MSCs-Exo) under high glucose (HG) and injected MSCs-Exo into diabetic mice, then we detected the NLRP3 inflammasome both in vitro and in vivo. We found that HG reduced the viability of podocytes, activated the NLRP3 signaling pathway and increased inflammation in podocytes and diabetic mice. MSCs-Exo attenuated the inflammation, including the expression of IL-6, IL-1ß, IL-18, TNF-α; depressed the activation of NLRP3 signaling pathway in podocytes under HG and diabetic mice, ameliorated kidney injury. Furthermore, miR-22-3p, which is relatively highly expressed miRNAs in exosomes of MSCs, may be the key point in this progress, by suppressing the expression of its known target, NLRP3. Knocking down miR-22-3p from MSCs-Exo abolished their anti-inflammation activity and beneficial function both in vitro and in vivo. Collectively, our results have demonstrated that exosomes transferring miR-22-3p protected the podocytes and diabetic mice from inflammation by mediating NLRP3 inflammasome, indicating that MSC-derived exosomes may be a promising therapeutic cell-free strategy for DKD.


Assuntos
Diabetes Mellitus Experimental , Nefropatias Diabéticas , Exossomos , Células-Tronco Mesenquimais , MicroRNAs , Camundongos , Humanos , Animais , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Diabetes Mellitus Experimental/terapia , Nefropatias Diabéticas/terapia , Exossomos/metabolismo , Transdução de Sinais , MicroRNAs/genética , MicroRNAs/metabolismo , Inflamação/metabolismo , Células-Tronco Mesenquimais/metabolismo
2.
Ren Fail ; 46(2): 2381597, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39039856

RESUMO

BACKGROUND AND AIMS: Diabetic kidney disease (DKD) is one of the most common complications of diabetes. It is reported that mesenchymal stem cells (MSCs) derived exosomes (MSCs-Exo) may have great clinical application potential for the treatment of DKD, but the underlying mechanism has not been illustrated. To clarify the effect of MSC-Exo on NOD2 signaling pathway in podocytes under high glucose (HG) and DKD, we conduct this study. METHODS: We co-cultured podocytes and MSCs-Exo under 30 mM HG and injected MSCs-Exo into DKD mice, then we detected the NOD2 signaling pathway by western blot, qRT-PCT, immunofluorescence, transmission electron microscopy and immunohistochemistry both in vitro and in vivo. RESULTS: In vitro, HG lead to the apoptosis, increased the ROS level and activated the NOD2 signaling pathway in podocytes, while MSCs-Exo protected podocytes from injury reduced the expression of inflammatory factors including TNF-α, IL-6, IL-1ß, and IL-18 and alleviated the inflammatory response, inhibited the activation of NOD2 signaling pathway and the expression of it's downstream protein p-P65, p-RIP2, prevented apoptosis, increased cell viability in podocytes caused by HG. In vivo, MSCs-Exo alleviated renal injury in DKD mice, protected renal function, decreased urinary albumin excretion and inhibited the activation of NOD2 signaling pathway as well as the inflammation in renal tissue. CONCLUSION: MSCs-Exo protected the podocytes and DKD mice from inflammation by mediating NOD2 pathway, MSCs-Exo may provide a new target for the treatment of DKD.


Assuntos
Apoptose , Nefropatias Diabéticas , Exossomos , Células-Tronco Mesenquimais , Proteína Adaptadora de Sinalização NOD2 , Podócitos , Transdução de Sinais , Animais , Exossomos/metabolismo , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/terapia , Células-Tronco Mesenquimais/metabolismo , Camundongos , Proteína Adaptadora de Sinalização NOD2/metabolismo , Podócitos/metabolismo , Podócitos/patologia , Masculino , Camundongos Endogâmicos C57BL , Glucose/metabolismo , Proteína Serina-Treonina Quinase 2 de Interação com Receptor/metabolismo , Técnicas de Cocultura , Transplante de Células-Tronco Mesenquimais/métodos , Espécies Reativas de Oxigênio/metabolismo , Rim/patologia , Rim/metabolismo , Diabetes Mellitus Experimental/complicações
3.
BMC Cancer ; 22(1): 872, 2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-35945526

RESUMO

BACKGROUND: The determination of HER2 expression status contributes significantly to HER2-targeted therapy in breast carcinoma. However, an economical, efficient, and non-invasive assessment of HER2 is lacking. We aimed to develop a clinicoradiomic nomogram based on radiomics scores extracted from multiparametric MRI (mpMRI, including ADC-map, T2W1, DCE-T1WI) and clinical risk factors to assess HER2 status. METHODS: We retrospectively collected 214 patients with pathologically confirmed invasive ductal carcinoma between January 2018 to March 2021 from Fudan University Shanghai Cancer Center, and randomly divided this cohort into training set (n = 128, 42 HER2-positive and 86 HER2-negative cases) and validation set (n = 86, 28 HER2-positive and 58 HER2-negative cases) at a ratio of 6:4. The original and transformed pretherapy mpMRI images were treated by semi-automated segmentation and manual modification on the DeepWise scientific research platform v1.6 ( http://keyan.deepwise.com/ ), then radiomics feature extraction was implemented with PyRadiomics library. Recursive feature elimination (RFE) based on logistic regression (LR) and LASSO regression were adpoted to identify optimal features before modeling. LR, Linear Discriminant Analysis (LDA), support vector machine (SVM), random forest (RF), naive Bayesian (NB) and XGBoost (XGB) algorithms were used to construct the radiomics signatures. Independent clinical predictors were identified through univariate logistic analysis (age, tumor location, ki-67 index, histological grade, and lymph node metastasis). Then, the radiomics signature with the best diagnostic performance (Rad score) was further combined with significant clinical risk factors to develop a clinicoradiomic model (nomogram) using multivariate logistic regression. The discriminative power of the constructed models were evaluated by AUC, DeLong test, calibration curve, and decision curve analysis (DCA). RESULTS: 70 (32.71%) of the enrolled 214 cases were HER2-positive, while 144 (67.29%) were HER2-negative. Eleven best radiomics features were retained to develop 6 radiomcis classifiers in which RF classifier showed the highest AUC of 0.887 (95%CI: 0.827-0.947) in the training set and acheived the AUC of 0.840 (95%CI: 0.758-0.922) in the validation set. A nomogram that incorporated the Rad score with two selected clinical factors (Ki-67 index and histological grade) was constructed and yielded better discrimination compared with Rad score (p = 0.374, Delong test), with an AUC of 0.945 (95%CI: 0.904-0.987) in the training set and 0.868 (95%CI: 0.789-0.948; p = 0.123) in the validation set. Moreover, calibration with the p-value of 0.732 using Hosmer-Lemeshow test demonstrated good agreement, and the DCA verified the benefits of the nomogram. CONCLUSION: Post largescale validation, the clinicoradiomic nomogram may have the potential to be used as a non-invasive tool for determination of HER2 expression status in clinical HER2-targeted therapy prediction.


Assuntos
Neoplasias da Mama , Carcinoma Ductal , Teorema de Bayes , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/genética , China , Feminino , Humanos , Antígeno Ki-67 , Nomogramas , Estudos Retrospectivos
4.
J Insect Sci ; 21(4)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34327530

RESUMO

We explored characterization of the mitochondrial genome (mitogenome or mtGenome) and phylogenetic analysis between 32 Fulgoroid species by sequencing and analyzing the mitogenome of Nisia fuliginosa Yang and Hu, 1985 (Hemiptera: Fulgoroidea: Meenoplidae), thereby making it the first determined mitogenome from the family Meenoplidae. The mitogenome was found to be 15,754 bp in length and contained 13 protein-coding genes (PCGs), 22 tRNA genes, two ribosomal RNA genes (rRNAs), and a control region. All PCGs started with typical ATN codons, except for nad1, which used GTG as the start codon. Canonical TAA termination codons were found in 10 PCGs and the remaining three genes (cox2, nad6, and nad1) had incomplete stop codons T. All tRNAs could fold into typical cloverleaf secondary structures, with the exception of trnC, trnV, and trnS1. Additionally, we compared the AT and GC skews of 13 PCGs of 32 Fulgoroidea mitogenomes, on the L-strand, the AT and GC skews were negative and positive, respectively. However, on the H-strand, the AT skew could be positive or negative and the GC skew was always negative. Phylogenetic results showed that the eight families of Fulgoroidea were divided into two large groups. Delphacidae formed a monophyletic group sister to a clade comprising Meenoplidae and other six families (Fulgoridae, Ricaniidae, Flatidae, Issidae, Caliscelidae, and Achilidae). Meenoplidae was located near the clade of Delphacidae, and Fulgoridae was located near the clade of Meenoplidae. Furthermore, Caliscelidae, Issidae, Ricaniidae, and Flatidae are closely related and they collectively formed a sister group to Achilidae.


Assuntos
Genoma Mitocondrial , Hemípteros/genética , Filogenia , Animais , Classificação , Ordem dos Genes , Genoma de Inseto , RNA Ribossômico/genética
5.
J Phys Chem A ; 124(47): 9692-9697, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33198457

RESUMO

Small-molecule anion carriers are potential reagents used in the treatment of diseases caused by dysregulated anion transport. Photoswitchable anion receptors, which can be reversibly switched between isomers by light and thereby cause reversible changes in anion binding affinity, have been receiving enormous interest. Here, based on the well-known photoswitch 1-N-methyl-3-phenylazopyrazole (3pzH), we designed a novel tetramethylamide-3pzH (3pzH_TA) photoswitchable receptor that achieves highly efficient and durable anion transportation. It enables high photoisomerization ratios of E → Z (>98%) and Z → E (97%) with a thermal half-life two times longer than that of 3pzH. We further demonstrated the high sensitivity of 3pzH_TA toward H2PO4- anion and revealed the key role of hydrogen bonds between H2PO4- and Z isomer in the strength of anion binding. Our findings open up a new strategy for the rational design and understanding of new types of photoswitchable anion receptors.


Assuntos
Compostos Azo/química , Luz , Fosfatos/química , Pirazóis/química , Ânions , Teoria da Densidade Funcional , Transporte de Íons , Isomerismo
6.
Int J Mol Sci ; 20(11)2019 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-31167447

RESUMO

To unravel the mechanisms behind the higher resistance to light damage of juvenile (JR) versus adult (AR) rats, Sprague Dawley rats were exposed to a bright luminous environment of 10, 000 lux. The light-induced retinopathy (LIR) was assessed with histology, electroretinography and immunohistochemistry (IHC). In JR, 2 days of exposure induced the typical LIR, while >3 days added little LIR. IHC revealed a subtle migration of microglia (Iba1 marker) from the inner to the outer retina after 3 days of exposure in JR contrasting with the stronger reaction seen after 1 day in AR. Similarly, in JR, the Müller cells expressed less intense GFAP, CNTF and FGF2 staining compared to AR. Our results suggest that in JR the degree of retinal damage is not proportional to the duration of light exposure (i.e., dose-independent retinopathy), contrasting with the dose-dependent LIR reported in AR. The immature immune system in JR may explain the delayed and/or weaker inflammatory response compared to AR, a finding that would also point to the devastating contribution of the immune system in generating the LIR phenotype, a claim also advanced to explain the pathophysiology of other retinal degenerative disorders such as Age-related Macular Degeneration, Diabetic Retinopathy and Retinitis Pigmentosa.


Assuntos
Luz/efeitos adversos , Doenças Retinianas/etiologia , Doenças Retinianas/metabolismo , Fatores Etários , Animais , Biomarcadores , Modelos Animais de Doenças , Fenômenos Eletrofisiológicos , Eletrorretinografia , Imunofluorescência , Imuno-Histoquímica , Ratos , Retina/imunologia , Retina/metabolismo , Retina/patologia , Retina/efeitos da radiação , Doenças Retinianas/patologia , Doenças Retinianas/fisiopatologia
7.
Phys Chem Chem Phys ; 18(6): 4835-41, 2016 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-26804157

RESUMO

ZnO nanorod/porous silicon nanowire (ZnO/PSiNW) hybrids with three different structures as highly sensitive NO2 gas sensors were obtained. PSiNWs were first synthesized by metal-assisted chemical etching, and then seeded in three different ways. After that ZnO nanorods were grown on the seeded surface of PSiNWs using a hydrothermal procedure. ZnO/PSiNW hybrids showed excellent gas sensing performance for various NO2 concentrations (5-50 ppm) at room temperature, and the electrical resistance change rate reached as high as 35.1% when responding to 50 ppm NO2. The distinct enhancement was mainly attributed to the faster carrier transportation after combination, the increase in gas sensing areas and the oxygen vacancy (VO) concentration. Moreover, the p-type gas sensing behavior was explained by the gas sensing mechanism and the effect of VO concentration on gas sensing properties was also discussed concerning the photoluminescence (PL) spectra performance.

8.
Cell Physiol Biochem ; 35(3): 1201-18, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25766531

RESUMO

BACKGROUND: Nitroalkene derivatives of oleic acid (OA-NO2) serve as high-affinity ligand for PPAR-γ, which regulates apoptosis, oxidation and inflammation and plays a central role in ischemia-reperfusion injury. In the present study, we elucidated the protective mechanisms of OA-NO2 against renal ischemia-reperfusion injury. METHODS: HK-2 cells were subjected to oxygen and glucose deprivation followed by re-oxygenation (OGD/R) to mimic renal ischemia-reperfusion injury. Cell apoptosis was analyzed by flow cytometry. Bax mitochondrial translocation, cytochrome c and apoptosis-inducing factor (AIF) cytosolic leakage and Akt/Gsk 3ß phosphorylation were evaluated by Western blotting. Bax activation was visualized by immunocytochemistry. GW9662 and siRNA transfection were employed to examine the involvement of PPAR-γ. RESULTS: OGD/R injury promoted mitochondrial translocation and activation of Bax, leakage of cytochrome c and AIF, subsequent caspase-3 activation, and eventually cell apoptosis. Pre-incubation with OA-NO2 (1.25 µM, 45min) inhibited Bax activation and blocked apoptotic cascade, while the protective effects were negated by GW9662 or PPAR-γ siRNA. Moreover, OA-NO2 restored Akt and Gsk 3ß phosphorylation in a PPAR-γ-dependent way. CONCLUSION: These findings suggest that OA-NO2 attenuates OGD/R-induced apoptosis by inhibiting Bax translocation and activation and the subsequent mitochondria-dependent apoptotic cascade in a PPAR-γ dependent manner.


Assuntos
Rim/efeitos dos fármacos , Ácido Oleico/administração & dosagem , PPAR gama/biossíntese , Traumatismo por Reperfusão/genética , Proteína X Associada a bcl-2/biossíntese , Anilidas/administração & dosagem , Apoptose/efeitos dos fármacos , Fator de Indução de Apoptose/biossíntese , Caspase 3/biossíntese , Hipóxia Celular/efeitos dos fármacos , Hipóxia Celular/genética , Citocromos c/biossíntese , Quinase 3 da Glicogênio Sintase/biossíntese , Glicogênio Sintase Quinase 3 beta , Humanos , Rim/lesões , Rim/patologia , Mitocôndrias/efeitos dos fármacos , PPAR gama/genética , Proteínas Proto-Oncogênicas c-akt/biossíntese , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/patologia , Transdução de Sinais/efeitos dos fármacos , Proteína X Associada a bcl-2/metabolismo
9.
Phys Chem Chem Phys ; 17(47): 31822-9, 2015 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-26565977

RESUMO

This work presents a new method to improve the field emission (FE) properties of semiconductors decorated with low-cost graphene oxide (GO) nanosheets and trace amounts of noble metal. The Ag/GO/ZnO composite emitter exhibited efficient FE properties with a low turn-on field of 1.4 V µm(-1) and a high field enhancement factor of 7018. The excellent FE properties of the Ag/GO/ZnO composite can be attributed to the tunneling effect of electrons through the heterojunction. The FE properties of the Ag/GO/ZnO composite are slightly better than those of the Ag/ZnO composite which forms an energy well that collects electrons on interfaces when an electric field is applied. This behavior is associated with heterostructures that offer more contact points and protrusions between ZnO nanowire arrays (NWAs) and Ag/GO, which leads to easier electron transfer. High-resolution transmission electron microscopy (HRTEM) and X-ray photoelectron spectroscopy (XPS) were employed to characterise the connection and evolution of the ZnO NWAs and Ag/GO composites.

10.
J Phys Chem A ; 119(16): 3770-9, 2015 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-25843772

RESUMO

Methylamine is the simplest aliphatic amine found in human urine, blood, and tissues. It is thought to play a significant part in central nervous system disturbances observed during renal and hepatic disease. In this work we have investigated the methylamine hydration clusters using a basin hopping (BH) algorithm with the density functional theory (DFT). The results presented herein yield a detailed understanding of the structure and stability for a system consisting of one methylamine molecule and up to seven waters: the most stable geometries arise from a fusion of tetramer or pentamer rings; by the geometrical parameters and topological parameters analysis, the strengths of the H2N···H-O hydrogen bonds of the global minima increase as the sizes of clusters increase, except for n = 5 where there is a slight fluctuation. This work may shed light on the form mechanism of methylamine existing in organisms and the hydration structures of larger molecules containing amino functional groups and their interaction with the water molecules nearby.


Assuntos
Metilaminas/química , Algoritmos , Ligação de Hidrogênio , Simulação de Dinâmica Molecular , Estrutura Molecular , Teoria Quântica
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