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1.
EMBO Rep ; 25(3): 971-990, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38279020

RESUMO

Tumor metastasis involves cells migrating directionally in response to external chemical signals. Reactive oxygen species (ROS) in the form of H2O2 has been demonstrated as a chemoattractant for neutrophils but its spatial characteristics in tumor microenvironment and potential role in tumor cell dissemination remain unknown. Here we investigate the spatial ROS distribution in 3D tumor spheroids and identify a ROS concentration gradient in spheroid periphery, which projects into a H2O2 gradient in tumor microenvironment. We further reveal the role of H2O2 gradient to induce chemotaxis of tumor cells by activating Src and subsequently inhibiting RhoA. Finally, we observe that the absence of mitochondria cristae remodeling proteins including the mitochondria-localized actin motor Myosin 19 (Myo19) enhances ROS gradient and promotes tumor dissemination. Myo19 downregulation is seen in many tumors, and Myo19 expression is negatively associated with tumor metastasis in vivo. Together, our study reveals the chemoattractant role of tumor microenvironmental ROS and implies the potential impact of mitochondria cristae disorganization on tumor invasion and metastasis.


Assuntos
Quimiotaxia , Peróxido de Hidrogênio , Espécies Reativas de Oxigênio , Miosinas/metabolismo , Fatores Quimiotáticos
2.
Hum Genomics ; 18(1): 80, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39014455

RESUMO

BACKGROUND: Keloid is a disease characterized by proliferation of fibrous tissue after the healing of skin tissue, which seriously affects the daily life of patients. However, the clinical treatment of keloids still has limitations, that is, it is not effective in controlling keloids, resulting in a high recurrence rate. Thus, it is urgent to identify new signatures to improve the diagnosis and treatment of keloids. METHOD: Bulk RNA seq and scRNA seq data were downloaded from the GEO database. First, we used WGCNA and MEGENA to co-identify keloid/immune-related DEGs. Subsequently, we used three machine learning algorithms (Randomforest, SVM-RFE, and LASSO) to identify hub immune-related genes of keloid (KHIGs) and investigated the heterogeneous expression of KHIGs during fibroblast subpopulation differentiation using scRNA-seq. Finally, we used HE and Masson staining, quantitative reverse transcription-PCR, western blotting, immunohistochemical, and Immunofluorescent assay to investigate the dysregulated expression and the mechanism of retinoic acid in keloids. RESULTS: In the present study, we identified PTGFR, RBP5, and LIF as KHIGs and validated their diagnostic performance. Subsequently, we constructed a novel artificial neural network molecular diagnostic model based on the transcriptome pattern of KHIGs, which is expected to break through the current dilemma faced by molecular diagnosis of keloids in the clinic. Meanwhile, the constructed IG score can also effectively predict keloid risk, which provides a new strategy for keloid prevention. Additionally, we observed that KHIGs were also heterogeneously expressed in the constructed differentiation trajectories of fibroblast subtypes, which may affect the differentiation of fibroblast subtypes and thus lead to dysregulation of the immune microenvironment in keloids. Finally, we found that retinoic acid may treat or alleviate keloids by inhibiting RBP5 to differentiate pro-inflammatory fibroblasts (PIF) to mesenchymal fibroblasts (MF), which further reduces collagen secretion. CONCLUSION: In summary, the present study provides novel immune signatures (PTGFR, RBP5, and LIF) for keloid diagnosis and treatment, and identifies retinoic acid as potential anti-keloid drugs. More importantly, we provide a new perspective for understanding the interactions between different fibroblast subtypes in keloids and the remodeling of their immune microenvironment.


Assuntos
Queloide , RNA-Seq , Queloide/genética , Queloide/diagnóstico , Queloide/patologia , Queloide/imunologia , Queloide/tratamento farmacológico , Humanos , Transcriptoma/genética , Perfilação da Expressão Gênica , Fibroblastos/metabolismo , Fibroblastos/patologia , Fibroblastos/imunologia , Redes Reguladoras de Genes , Tretinoína/farmacologia , Tretinoína/uso terapêutico , Análise de Célula Única/métodos , Diferenciação Celular/genética , Análise de Sequência de RNA/métodos , Aprendizado de Máquina , Análise da Expressão Gênica de Célula Única
3.
Small ; 20(15): e2305296, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38010122

RESUMO

Developing a highly active, durable, and low-platinum-based electrocatalyst for the cathodic oxygen reduction reaction (ORR) is for breaking the bottleneck of large-scale applications of proton exchange membrane fuel cells (PEMFCs). Herein, ultrafine PtZn intermetallic nanoparticles with low Pt-loading and trace germanium (Ge) involvement confined in the nitrogen-doped porous carbon (Ge-L10-PtZn@N-C) are reported. The Ge-L10-PtZn@N-C exhibit superior ORR activity with a mass activity of 3.04 A mg-1 Pt and specific activity of 4.69 mA cm-2, ≈12.2- and 10.2-times improvement compared to the commercial Pt/C (20%) at 0.90 V in 0.1 m KOH. The cathodic catalyst Ge-L10-PtZn@N-C assembled in the PEMFC shows encouraging peak power densities of 316.5 (at 0.86 V) and 417.2 mW cm-2 (at 0.91 V) in alkaline and acidic fuel-cell, respectively. The combination of experiment and density functional theory calculations (DFT) results robustly reveal that the participation of trace Ge can not only trigger a "growth site locking effect" to effectively inhibit nanoparticle growth, bring miniature nanoparticles, enhance dispersion uniformity, and achieve the exposure of the more electrochemical active site, but also effectively modulates the electronic structure, hence optimizing the adsorption/desorption of the oxygen intermediates.

4.
Nanotechnology ; 34(49)2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37666240

RESUMO

Two-dimensional (2D) PdSe2film has the characteristics of adjustable bandgap, high carrier mobility, and high stability. Photodetector (PD) based on 2D PdSe2exhibits wide spectral self-driving features, demonstrating enormous potential in the field of optical detection. Here, we design and fabricate PdSe2/Si heterojunction PDs with various thicknesses of the PdSe2films from 10 to 35 nm. Due to the enhancement of light absorption capacity and built-in electric field of heterojunction, the photodetector with thicker PdSe2film can generate more photo-generated carriers and effectively separate them to form a large photocurrent, thus showing more excellent photodetection performance. The responsivity and specific detectivity of the PdSe2/Si PDs with 10 nm, 20 nm, and 35 nm PdSe2films are 2.12 A W-1and 6.72 × 109Jones, 6.17 A W-1and 1.95 × 1010Jones, and 8.02 A W-1and 2.54 × 1010Jones, respectively (808 nm illumination). The PD with 35 nm PdSe2film exhibits better performance than the other two PDs, with the rise/fall times of 15.8µs/138.9µs atf= 1 kHz and the cut-off frequency of 8.6 kHz. Furthermore, we demonstrate that the properties of PdSe2/Si PD array have excellent uniformity and stability at room temperature and shows potential for image sensing in the UV-vis-NIR wavelength range.

5.
Int J Mol Sci ; 23(21)2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36362183

RESUMO

Rheumatoid arthritis (RA) is a common disease worldwide and is treated commonly with methotrexate (MTX). CS12192 is a novel JAK3 inhibitor discovered by Chipscreen Biosciences for the treatment of autoimmune diseases. In the present study, we examined the therapeutic effect of CS12192 against RA and explored if the combinational therapy of CS12192 and MTX produced a synergistic effect against RA in rat collagen-induced arthritis (CIA). Arthritis was induced in male Sprague-Dawley rats by two intradermal injections of bovine type II collagen (CII) and treated with MTX, CS12192, or the combination of CS12192 and MTX daily for two weeks. Effects of different treatments on arthritis score, X-ray score, pathology, and expression of inflammatory cytokines and biomarkers were examined. We found that treatment with either CS12192 or MTX produced a comparable therapeutic effect on CIA including: (1) significantly lowering the arthritis score, X-ray score, serum levels of rheumatic factor (RF), C-reactive protein (CRP), and anti-nuclear antibodies (ANA); (2) largely alleviating histopathological damage, reducing infiltration of Th17 cells while promoting Treg cells; (3) inhibiting the expression of inflammatory cytokines and chemokines such as IL-1ß, TNF-α, IL-6, CCL2, and CXCL1. All these inhibitory effects were further improved by the combinational therapy with MTX and CS12192. Of importance, the combinational treatment also resulted in a marked switching of the Th17 to Treg and the M1 to M2 immune responses in synovial tissues of CIA. Thus, when compared to the monotherapy, the combination treatment with CS12192 and MTX produces a better therapeutic effect against CIA with a greater suppressive effect on T cells and macrophage-mediated joint inflammation.


Assuntos
Artrite Experimental , Artrite Reumatoide , Inibidores de Janus Quinases , Ratos , Masculino , Bovinos , Animais , Metotrexato/uso terapêutico , Ratos Sprague-Dawley , Artrite Experimental/patologia , Citocinas/metabolismo , Inibidores de Janus Quinases/efeitos adversos
6.
Liver Int ; 40(9): 2293-2304, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32394491

RESUMO

BACKGROUND & AIM: Shortage of donor hepatocytes limits hepatocyte transplantation for clinical application. Induced hepatic stem cells (iHepSCs) have capacities of self-renewal and bipotential differentiations. Here, we investigated whether iHepSCs could be extensively expanded, and whether they could differentiate into sufficient functional hepatocytes as donors for transplantation therapy after their extensive expansions. METHODS: Murine extensively expanded iHepSCs (50-55 passages) were induced to differentiate into iHepSC-Heps under a chemically defined condition. iHepSC-Heps were proved for carrying morphological hepatocyte characters and hepatocytic functions including low-density lipoprotein uptake, glycogen storage, CLF secretion, ICG uptake and release, Alb secretion, urea synthesis and metabolism-relative gene expressions respectively. Next, both iHepSCs and iHepSC-Heps were transplanted into Fah-/- mice respectively. Both liver repopulation and alleviation of liver function were compared between two transplantation groups. RESULTS: Murine iHepSCs still maintained the capacities of self-renewal and bipotential differentiations after extensive expansion. The efficiency for the functional hepatocyte differentiation from extensively expanded iHepSCs reached to 72.64%. Transplantations of both extensively expanded iHepSCs and iHepSC-Heps resulted in liver engraftment in Fah-/- mice. Survival rate of Fah-/- mice recipients and level of liver repopulation were 50% and 20.32 ± 4.58% respectively in iHepSC-Heps group, while 33% and 10.4 ± 4.3% in iHepSCs group. CONCLUSIONS: Extensively expanded iHepSCs can efficiently differentiate into hepatocytes in chemical defined medium. Transplantation of iHepSC-Heps was more effective and more efficient than transplantation of iHepSCs in Fah-/- mice. Our results suggested an innovative system to obtain sufficient hepatocytes through hepatic differentiation of iHepSCs generated by lineage reprogramming.


Assuntos
Hepatócitos , Fígado , Animais , Diferenciação Celular , Camundongos , Células-Tronco
7.
Zhongguo Yi Liao Qi Xie Za Zhi ; 44(4): 315-318, 2020 Apr 08.
Artigo em Zh | MEDLINE | ID: mdl-32762204

RESUMO

Based on the analysis of the theoretical calculation model of axial resolution of optical coherence tomograph for the posterior segment of the human eye, a set of testing device for measuring its axial resolution is designed and developed. In view of a commercial ophthalmic optical coherence tomograph in clinical use, its axial resolution is calculated to be 5.07 µm theoretically, and the actual measurement value is 5.45 µm. The uncertainty of the detection device is evaluated and the result is (5.45±0.10) µm. The measurement error introduced by the testing device is very small. Meanwhile, the axial resolution measured by the testing device meets the requirements of the instrument(≤ 6 µm).


Assuntos
Algoritmos , Olho/diagnóstico por imagem , Tomografia de Coerência Óptica , Humanos , Incerteza
8.
Biochem Biophys Res Commun ; 516(2): 591-598, 2019 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-31239154

RESUMO

In the fumarylacetoacetate hydrolase deficient (Fah-/-) mouse, massive liver repopulation can be easily obtained after transplanted hepatocytes. Understanding the mechanisms of complete liver repopulation in Fah-/- mice will be useful for future clinical application. Here, we found that the endogenous hepatocytes in liver of Fah-/- mice undertook senescence during the time of tyrosinemia symptoms. Increase of senescent hepatocytes in Fah-/- mice provided proliferative advantage to the transplanted hepatocytes. Importantly, senescent hepatocytes upregulated the expression of extracellular matrix enzyme, contributing to degradation of extracellular matrix components and weakness of cell adhesion and connection. The liver exhibiting a loose architecture provided the space for the engraftment and expansion of transplanted hepatocytes. These findings underscore the underlying mechanisms of completed liver repopulation in Fah-/- mice. Senescence followed by loose hepatic parenchyma is a preconditioning for liver repopulation, which would be a promising strategy to achieve therapeutic liver repopulation in clinical settings.


Assuntos
Senescência Celular , Hepatócitos/citologia , Fígado/citologia , Animais , Pontos de Checagem do Ciclo Celular , Proliferação de Células , Cicloexanonas , Hepatócitos/transplante , Hidrolases/deficiência , Hidrolases/metabolismo , Camundongos , Nitrobenzoatos
9.
FASEB J ; 32(9): 4670-4680, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29601782

RESUMO

Exercise plays an important role in the prevention and treatment of chronic liver disease and associated metabolic disorders. A single bout of exercise induces tissue blood flow redistribution, which decreases splanchnic circulation and leads to physiologic hypoxia in the gastrointestinal system and liver. The transcription factor, hypoxia inducible factor-1α (HIF-1α), and its regulator, prolylhydroxylase 2 (PHD2), play pivotal roles in the response to oxygen flux by regulating downstream gene expression levels in the liver. We hypothesized that exercise increases the HIF-1α levels in the liver, and that the hepatic PHD2/HIF-1α axis is involved in postexercise restoration of systemic energy homeostasis. Through constant O2 consumption, CO2 production, food and water intake, and physical activity detection with metabolic chambers, we observed that one 30-min session of swimming exercise enhances systemic energy metabolism in mice. By using the noninvasive bioluminescence imaging ROSA26 oxygen-dependent domain Luc mouse model, we reveal that exercise increases in vivo HIFα levels in the liver. Intraperitoneal injections of the PHD inhibitor, dimethyloxalylglycine, mimicked exercise-induced HIFα increase, whereas the HIF-1α inhibitor, PX-478, blocked this effect. We next constructed liver-specific knockout (LKO) mouse models with albumin- Cre-mediated, hepatocyte-specific Hif1a and Phd2 deletion. Compared with their controls, Hif1a-LKO and Phd2-LKO mice exhibited distinct patterns of hepatic metabolism-related gene expression profiles. Moreover, Hif1a-LKO mice failed to restore systemic energy homeostasis after exercise. In conclusion, the current study demonstrates that a single bout of exercise disrupts systemic energy homeostasis, increasing the HIF-1α levels in the liver. These findings also provide evidence that the hepatic PHD2/HIF-1α axis is involved in postexercise systemic metabolic homeostasis.-Luo, B., Xiang, D., Wu, D., Liu, C., Fang, Y., Chen, P., Hu, Y.-P. Hepatic PHD2/HIF-1α axis is involved in postexercise systemic energy homeostasis.


Assuntos
Homeostase/genética , Prolina Dioxigenases do Fator Induzível por Hipóxia/genética , Fígado/metabolismo , Pró-Colágeno-Prolina Dioxigenase/metabolismo , Animais , Linhagem Celular Tumoral , Expressão Gênica/genética , Regulação da Expressão Gênica/genética , Camundongos Transgênicos , Oxigênio/metabolismo , Prolil Hidroxilases/genética , RNA Mensageiro/genética
10.
BMC Ophthalmol ; 19(1): 59, 2019 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-30791880

RESUMO

BACKGROUND: To evaluate the effects of anterior capsular opening size on deviation from predicted refraction and the effective position of the intraocular lens (ELP) in cataract surgery. METHODS: Nonrandomized clinical trial. Eighty patients (80 eyes) with simple age-related cataracts were treated from May 2018 to September 2018 at the Fourth Affiliated Hospital of China Medical University. All patients undergoing phacoemulsification received intraocular lens based on the voluntary principle. Forty eyes were implanted with the C-loop haptic intraocular lens (AMO Tecnis ZCB00) while the other 40 eyes were implanted with the plate haptic intraocular lens (CT ASPHINA 509 M). Follow-up visits were conducted postoperatively at 1 week, 1 month, and 3 months during which patients underwent refraction and data collection after pupil dilation, which included anterior segment photography and Scheimpflug imaging by Pentacam. The area, horizontal and vertical diameter of the capsulorrhexis, circularity, decentration, and package were analysed using the image analysis software Image-Pro-Plus 6.0,then evaluated the relationship between the different shapes of capsulorrhexis with deviation from predicted refraction and ELP in cataract surgery. RESULTS: Deviation from predicted refraction and all of the parameters of capsulorrhexis were not correlative in the 509 M IOL group, however, in the Tecnis IOL group, while the deviation from predicted refraction and all of the capsulorrhexis parameters were not correlative at 1 week, the deviation from predicted refraction did correlate with capsulorrhexis area, horizontal diameter at 1 month (P = 0.029, P = 0.048), and with capsulorrhexis area, vertical diameter at 3 months (P = 0.03, P = 0.017). The ELP correlated with package in both groups postoperatively (r > 0, P < 0.05), but there is no other capsulorrhexis parameters correlated with ELP in the 509 M IOL group (all P > 0.05). For the Tecnis IOL group, the ELP and capsulorrhexis area were correlated at 1 week and 1 month, while the ELP and horizontal diameter, the ELP and vertical diameter were correlated at 1 week, but did not correlate with the other capsulorrhexis parameters in the Tecnis IOL group (all P > 0.05). CONCLUSIONS: The shape of the capsulorrhexis has an effect on postoperative refractive outcomes and the effective position of the intraocular lens in cataract surgery, and plate haptic intraocular lenses have better refractive stability than C-loop haptic intraocular lenses. TRIAL REGISTRATION: ChiCTR1800015638 ,2018-04-12.


Assuntos
Capsulorrexe/métodos , Implante de Lente Intraocular/métodos , Lentes Intraoculares , Facoemulsificação , Refração Ocular/fisiologia , Idoso , Análise de Variância , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório
11.
Zhongguo Yi Liao Qi Xie Za Zhi ; 43(1): 21-24, 2019 Jan 30.
Artigo em Zh | MEDLINE | ID: mdl-30770685

RESUMO

Based on the Gullstrand I model eye, a simplified model eye for testing fundus imaging device is designed. The model eye can reach the following requirements:(1) The refractive characteristics of the ocular refractive tissue are simulated, and the equivalent focal length in air is 17 mm; (2) The differences between relative refractive index differences of the adjacent materials of the simplified model eye and relative refractive index differences of any adjacent two layers (cornea and aqueous humor, aqueous humor and lens, lens and vitreous body) of the Gullstrand I model eye are not more than 1%; (3) In the case of the incident aperture diameter of 3 mm, the differences of radii of the diffuse spots formed by the paraxial light and the axial light are not more than 15%; (4) The differences of angles of chief ray and tangent line of the fundus are not more than 1°; (5) In the case of the incident aperture diameter of 3 mm, the differences of MTF values of the near axis light are not more than 0.1. The simplified model eye can be expected to be used for testing fundus imaging device instead of the test method in ISO 10940:2009 Ophthalmic instruments-Fundus cameras.


Assuntos
Cristalino , Refração Ocular , Córnea , Fundo de Olho , Cristalino/diagnóstico por imagem
12.
Development ; 142(2): 385-93, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25564625

RESUMO

The terminal differentiation of hypertrophic chondrocytes is a tightly regulated process that plays a pivotal role in endochondral ossification. As a negative regulator, Sox9 is essentially downregulated in terminally differentiated hypertrophic chondrocytes. However, the underlying mechanism of Sox9 silencing is undefined. Here we show that the zinc finger protein Zbtb20 regulates the terminal differentiation of hypertrophic chondrocytes by repressing Sox9. In the developing skeleton of the mouse, Zbtb20 protein is highly expressed by hypertrophic chondrocytes from late embryonic stages. To determine its physiological role in endochondral ossification, we have generated chondrocyte-specific Zbtb20 knockout mice and demonstrate that disruption of Zbtb20 in chondrocytes results in delayed endochondral ossification and postnatal growth retardation. Zbtb20 deficiency caused a delay in cartilage vascularization and an expansion of the hypertrophic zone owing to reduced expression of Vegfa in the hypertrophic zone. Interestingly, Sox9, a direct suppressor of Vegfa expression, was ectopically upregulated at both mRNA and protein levels in the late Zbtb20-deficient hypertrophic zone. Furthermore, knockdown of Sox9 greatly increased Vegfa expression in Zbtb20-deficient hypertrophic chondrocytes. Our findings point to Zbtb20 as a crucial regulator governing the terminal differentiation of hypertrophic chondrocytes at least partially through repression of Sox9.


Assuntos
Diferenciação Celular/fisiologia , Condrócitos/fisiologia , Osteogênese/fisiologia , Fatores de Transcrição SOX9/antagonistas & inibidores , Fatores de Transcrição/metabolismo , Análise de Variância , Animais , Imunoprecipitação da Cromatina , Técnicas Histológicas , Imuno-Histoquímica , Hibridização In Situ , Camundongos , Camundongos Knockout , Interferência de RNA , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição SOX9/genética , Fatores de Transcrição/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
13.
Mol Cell Biochem ; 449(1-2): 47-54, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29532226

RESUMO

Hepatocellular carcinoma (HCC) is among the most common lethal cancers of the digestive system with poor prognosis rates and ineffective therapeutic options. Matrine, a traditional Chinese medicine found in the roots of sophora species, has been used in the clinical treatment of liver fibrosis, chronic hepatitis B and other diseases. We have synthesized a matrine derivatives named WM622 (C26H35ON3S2) with a significant inhibitory effect on transplanted tumors in vivo. The half inhibitory concentration (IC50) of WM622 is 34 µM, which is much lower than matrine. WM622 inhibited the proliferation and promoted apoptosis of hepatocellular carcinoma cells significantly, and the cell cycle was blocked in G0/G1 phase. The protein phosphorylation levels of EGFR, AKT, PI3K and GSK3ß (p-EGFR, p-AKT, p-PI3K, and p-GSK3ß) were also decreased by WM622 treatment dose dependently. In tumor-bearing mice, WM622 could reduce the tumor volumes. In conclusion, the study demonstrated that WM622 could inhibit the proliferation of the hepatocellular carcinoma both in vivo and in vitro by inducing apoptosis, blocking cell cycle in G0/G1 phase and inhibiting the PI3K/AKT signal pathways.


Assuntos
Alcaloides , Carcinoma Hepatocelular/metabolismo , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Neoplasias Hepáticas/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Quinolizinas , Fase de Repouso do Ciclo Celular/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Alcaloides/química , Alcaloides/farmacologia , Animais , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Pontos de Checagem da Fase G1 do Ciclo Celular/genética , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Quinolizinas/química , Quinolizinas/farmacologia , Fase de Repouso do Ciclo Celular/genética , Transdução de Sinais/genética , Matrinas
14.
Nature ; 475(7356): 386-9, 2011 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-21562492

RESUMO

The generation of functional hepatocytes independent of donor liver organs is of great therapeutic interest with regard to regenerative medicine and possible cures for liver disease. Induced hepatic differentiation has been achieved previously using embryonic stem cells or induced pluripotent stem cells. Particularly, hepatocytes generated from a patient's own induced pluripotent stem cells could theoretically avoid immunological rejection. However, the induction of hepatocytes from induced pluripotent stem cells is a complicated process that would probably be replaced with the arrival of improved technology. Overexpression of lineage-specific transcription factors directly converts terminally differentiated cells into some other lineages, including neurons, cardiomyocytes and blood progenitors; however, it remains unclear whether these lineage-converted cells could repair damaged tissues in vivo. Here we demonstrate the direct induction of functional hepatocyte-like (iHep) cells from mouse tail-tip fibroblasts by transduction of Gata4, Hnf1α and Foxa3, and inactivation of p19(Arf). iHep cells show typical epithelial morphology, express hepatic genes and acquire hepatocyte functions. Notably, transplanted iHep cells repopulate the livers of fumarylacetoacetate-hydrolase-deficient (Fah(-/-)) mice and rescue almost half of recipients from death by restoring liver functions. Our study provides a novel strategy to generate functional hepatocyte-like cells for the purpose of liver engineering and regenerative medicine.


Assuntos
Diferenciação Celular , Fibroblastos/citologia , Fibroblastos/metabolismo , Hepatócitos/citologia , Hepatócitos/metabolismo , Animais , Diferenciação Celular/genética , Linhagem da Célula , Células Cultivadas , Inibidor p16 de Quinase Dependente de Ciclina/deficiência , Inibidor p16 de Quinase Dependente de Ciclina/genética , Proteínas de Ligação a DNA/deficiência , Fator de Transcrição GATA4/genética , Fator de Transcrição GATA4/metabolismo , Perfilação da Expressão Gênica , Fator 1-alfa Nuclear de Hepatócito/genética , Fator 1-alfa Nuclear de Hepatócito/metabolismo , Fator 3-gama Nuclear de Hepatócito/genética , Fator 3-gama Nuclear de Hepatócito/metabolismo , Hepatócitos/fisiologia , Hepatócitos/transplante , Hidrolases/deficiência , Hidrolases/genética , Fígado/citologia , Fígado/enzimologia , Fígado/fisiologia , Fígado/fisiopatologia , Hepatopatias/enzimologia , Hepatopatias/patologia , Hepatopatias/fisiopatologia , Hepatopatias/terapia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Medicina Regenerativa/métodos , Taxa de Sobrevida , Cauda/citologia , Engenharia Tecidual/métodos , Transdução Genética
15.
Hepatology ; 60(1): 349-61, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24711261

RESUMO

UNLABELLED: A better understanding of hepatocyte senescence could be used to treat age-dependent disease processes of the liver. Whether continuously proliferating hepatocytes could avoid or reverse senescence has not yet been fully elucidated. We confirmed that the livers of aged mice accumulated senescent and polyploid hepatocytes, which is associated with accumulation of DNA damage and activation of p53-p21 and p16(ink4a)-pRB pathways. Induction of multiple rounds continuous cell division is hard to apply in any animal model. Taking advantage of serial hepatocyte transplantation assays in the fumarylacetoacetate hydrolase-deficient (Fah(-/-)) mouse, we studied the senescence of hepatocytes that had undergone continuous cell proliferation over a long time period, up to 12 rounds of serial transplantations. We demonstrated that the continuously proliferating hepatocytes avoided senescence and always maintained a youthful state. The reactivation of telomerase in hepatocytes after serial transplantation correlated with reversal of senescence. Moreover, senescent hepatocytes harvested from aged mice became rejuvenated upon serial transplantation, with full restoration of proliferative capacity. The same findings were also true for human hepatocytes. After serial transplantation, the high initial proportion of octoploid hepatocytes decreased to match the low level of youthful liver. CONCLUSION: These findings suggest that the hepatocyte "ploidy conveyer" is regulated differently during aging and regeneration. The findings of reversal of hepatocyte senescence could enable future studies on liver aging and cell therapy.


Assuntos
Proliferação de Células , Senescência Celular/fisiologia , Hepatócitos/citologia , Hepatócitos/transplante , Regeneração Hepática/fisiologia , Animais , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Citometria de Fluxo , Hepatócitos/fisiologia , Hidrolases/genética , Óperon Lac , Fígado/citologia , Fígado/fisiologia , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Knockout , Poliploidia , Telomerase/metabolismo , Proteína Supressora de Tumor p53/metabolismo
16.
Chin Med Sci J ; 30(2): 95-9, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26149000

RESUMO

OBJECTIVE: To observe the sensitivity of stroke volume variation (SVV) for assessing volume change during induction period of general anesthesia. METHODS: Patients who underwent orthopaedic surgery under general anesthesia and mechanical ventilation were divided into two groups randomly. Patients in the group Ⅰwere subjected to progressive central hypovolemia and correction of hypovolemia sequentially; patients in the Group Ⅱ were exposed to hypervolemia alone. Each step was implemented after 5 minutes when the hemodynamics was stable. SVV and cardiac index (CI) were recorded, and Pearson's product-moment correlation was used to analyze correlation between SVV and CI. RESULTS: Forty patients were included in this study, 20 cases in each group. For group Ⅰ patients, SVV was increased significantly along with blood volume reduction, and changes in CI were negatively correlated with changes in SVV (r=-0.605, P<0.01); SVV decreased significantly along with correction of blood volume; changes in CI were negatively correlated with changes in SVV (r=-0.651, P<0.01). For group Ⅱ patients, along with blood volume increase, SVV did not change significantly; changes in CI revealed no significant correlation with changes in SVV (r=0.067, P>0.05). CONCLUSION: SVV is a useful indicator for hypovolemia, but not for hypervolemia.


Assuntos
Pressão Arterial , Débito Cardíaco , Volume Sistólico , Adulto , Idoso , Volume Sanguíneo , Pressão Venosa Central , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Período Perioperatório
17.
PLoS One ; 19(5): e0304327, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38820423

RESUMO

Based on the land economic density of 892 town units, the spatial pattern of the land economic density in Zhejiang Province is analyzed using the coefficient of variation, spatial classification, and spatial correlation methods, and the influencing factors are analyzed using a spatial regression model. The results are as follows: (1) The coefficients of variation were 2.6 and 3.1 in 2014 and 2019, respectively, indicating that the degree of imbalance of the town's industrial economy at the county level increased. (2) The distribution of the high-level agglomeration areas was characterized by one core area and two sub-core areas. The main core area was located at the junction of Hangzhou City, Shaoxing City, and Jiaxing City, and the two sub-core areas were located in Yuyao City and the main urban area of Ningbo City. In addition, several small-scale agglomeration areas composed of medium and high-level units were distributed in Wenzhou City. (3) The high-value agglomeration and low-value agglomeration distribution in the spatial correlation patterns was identified using the spatial auto-correlation method. The hot spots and sub-hot spots were distributed in Northern Zhejiang, and the cold spots formed a large-scale agglomeration in Quzhou City, Lishui City, Taizhou City, and several other cities in Southern Zhejiang. (4) Compared with the county scale, the spatial scope of the high-level areas in Northern Zhejiang shrunk significantly at the township scale, and the high-level agglomeration areas along the southeast coast changed into a cluster of several townships. (5) According to the geographically weighted regression (GWR) model, the importance of influencing factors is as follows: population density > regional area > industrial output value per capita > total population > proportion of secondary and tertiary personnel > total employees.


Assuntos
Análise Espaço-Temporal , China , Humanos , Cidades , Urbanização , Desenvolvimento Econômico
18.
PLoS One ; 19(6): e0304795, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38900771

RESUMO

BACKGROUND: This meta-analysis investigated the influence of exercise on cognitive function in people living with diabetes. METHODS: Stringent criteria for literature inclusion and exclusion were defined. Searches were conducted across four English databases to gather randomized controlled trials investigating exercise interventions for cognitive function in people living with diabetes. Outcome indicators from 1193 subjects across 12 articles were analyzed using RevMan 5.4 software. RESULTS: Exercise intervention demonstrated the ability to mitigate cognitive decline in people living with diabetes, with a combined effect size (standardized mean difference) of 0.91, 95% CI: 0.28, 1.54, P < 0.00001. The intervention effect showed significant modulation by intervention content (I2 = 95%), intervention duration (I2 = 95%), intervention frequency (I2 = 95%), and intervention cycle (I2 = 96%). Among these factors, multi-component exercise, sessions >40 minutes, exercise frequency >4 times per week, and sustained exercise for >6 months were paramount, all with P < 0.05. CONCLUSION: Exercise intervention emerges as a viable strategy for delaying cognitive decline in people living with diabetes. Its efficacy is subject to modulation by various variables. Optimal intervention includes multi-component exercise, individual sessions lasting 40-60 minutes, exercising >4 times a week, and continuous exercise for over 6 months.


Assuntos
Cognição , Humanos , Cognição/fisiologia , Diabetes Mellitus/fisiopatologia , Diabetes Mellitus/terapia , Diabetes Mellitus/psicologia , Exercício Físico/fisiologia , Terapia por Exercício/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto
19.
Adv Sci (Weinh) ; : e2308711, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38881531

RESUMO

Understanding the liver stem cells (LSCs) holds great promise for new insights into liver diseases and liver regeneration. However, the heterogenicity and plasticity of liver cells have made it controversial. Here, by employing single-cell RNA-sequencing technology, transcriptome features of Krt19+ bile duct lineage cells isolated from Krt19CreERT; Rosa26R-GFP reporter mouse livers are examined. Distinct biliary epithelial cells which include adult LSCs, as well as their downstream hepatocytes and cholangiocytes are identified. Importantly, a novel cell surface LSCs marker, CD63, as well as CD56, which distinguished active and quiescent LSCs are discovered. Cell expansion and bi-potential differentiation in culture demonstrate the stemness ability of CD63+ cells in vitro. Transplantation and lineage tracing of CD63+ cells confirm their contribution to liver cell mass in vivo upon injury. Moreover, CD63+CD56+ cells are proved to be activated LSCs with vigorous proliferation ability. Further studies confirm that CD63+CD56- quiescent LSCs express VEGFR2 and FGFR1, and they can be activated to proliferation and differentiation through combination of growth factors: VEGF-A and bFGF. These findings define an authentic adult liver stem cells compartment, make a further understanding of fate regulation on LSCs, and highlight its contribution to liver during pathophysiologic processes.

20.
Proc Natl Acad Sci U S A ; 107(14): 6510-5, 2010 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-20308569

RESUMO

The development of hippocampal circuitry depends on the proper assembly of correctly specified and fully differentiated hippocampal neurons. Little is known about factors that control the hippocampal specification. Here, we show that zinc finger protein Zbtb20 is essential for the specification of hippocampal CA1 field identity. We found that Zbtb20 expression was initially activated in the hippocampal anlage at the onset of corticogenesis, and persisted in immature hippocampal neurons. Targeted deletion of Zbtb20 in mice did not compromise the progenitor proliferation in the hippocampal and adjacent transitional ventricular zone, but led to the transformation of the hippocampal CA1 field into a transitional neocortex-like structure, as evidenced by cytoarchitectural, neuronal migration, and gene expression phenotypes. Correspondingly, the subiculum was ectopically located adjacent to the CA3 in mutant. Although the field identities of the mutant CA3 and dentate gyrus (DG) were largely maintained, their projections were severely impaired. The hippocampus of Zbtb20 null mice was reduced in size, and exhibited increased apoptotic cell death during postnatal development. Our data establish an essential role of Zbtb20 in the specification of CA1 field identity by repressing adjacent transitional neocortex-specific fate determination.


Assuntos
Região CA1 Hipocampal/embriologia , Região CA1 Hipocampal/metabolismo , Fatores de Transcrição/metabolismo , Animais , Apoptose , Região CA1 Hipocampal/citologia , Região CA1 Hipocampal/crescimento & desenvolvimento , Deleção de Genes , Regulação da Expressão Gênica no Desenvolvimento , Camundongos , Camundongos Knockout , Fatores de Transcrição/deficiência , Fatores de Transcrição/genética
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