A novel 4H-Si C trench insulated gate bipolar transistor(IGBT)with a controllable hole-extracting(CHE)path is proposed and investigated in this paper.The CHE path is controlled by metal semiconductor gate(MES gate)and...A novel 4H-Si C trench insulated gate bipolar transistor(IGBT)with a controllable hole-extracting(CHE)path is proposed and investigated in this paper.The CHE path is controlled by metal semiconductor gate(MES gate)and metal oxide semiconductor gate(MOS gate)in the p-shield region.The grounded p-shield region can significantly suppress the high electric field around gate oxide in Si C devices,but it weakens the conductivity modulation in the Si C trench IGBT by rapidly sweeping out holes.This effect can be eliminated by introducing the CHE path.The CHE path is pinched off by the high gate bias voltage at on-state to maintain high conductivity modulation and obtain a comparatively low on-state voltage(VON).During the turn-off transient,the CHE path is formed,which contributes to a decreased turn-off loss(EOFF).Based on numerical simulation,the EOFFof the proposed IGBT is reduced by 89%compared with the conventional IGBT at the same VONand the VONof the proposed IGBT is reduced by 50%compared to the grounded p-shield IGBT at the same EOFF.In addition,the average power reduction for the proposed device can be 51.0%to 81.7%and 58.2%to 72.1%with its counterparts at a wide frequency range of 500 Hz to 10 k Hz,revealing a great improvement of frequency characteristics.展开更多
Parathyroid hormone(PTH) regulates bone remodeling by activating PTH type 1 receptor(PTH1R) in osteoblasts/osteocytes. Insulinlike growth factor type 1(IGF-1) stimulates mesenchymal stem cell differentiation to osteob...Parathyroid hormone(PTH) regulates bone remodeling by activating PTH type 1 receptor(PTH1R) in osteoblasts/osteocytes. Insulinlike growth factor type 1(IGF-1) stimulates mesenchymal stem cell differentiation to osteoblasts. However, little is known about the signaling mechanisms that regulates the osteoblast-to-osteocyte transition. Here we report that PTH and IGF-I synergistically enhance osteoblast-to-osteocyte differentiation. We identified that a specific tyrosine residue, Y494, on the cytoplasmic domain of PTH1R can be phosphorylated by insulin-like growth factor type I receptor(IGF1R) in vitro. Phosphorylated PTH1R localized to the barbed ends of actin filaments and increased actin polymerization during morphological change of osteoblasts into osteocytes.Disruption of the phosphorylation site reduced actin polymerization and dendrite length. Mouse models with conditional ablation of PTH1R in osteoblasts demonstrated a reduction in the number of osteoctyes and dendrites per osteocyte, with complete overlap of PTH1R with phosphorylated-PTH1R positioning in osteocyte dendrites in wild-type mice. Thus, our findings reveal a novel signaling mechanism that enhances osteoblast-to-osteocyte transition by direct phosphorylation of PTH1R by IGF1R.展开更多
Survival of children with chronic medical illnesses is leading to an increase in secondary osteoporosis due to impaired peak bone mass (PBM). Insulin-like growth factor type Ⅰ (IGF-1) levels correlate with the pa...Survival of children with chronic medical illnesses is leading to an increase in secondary osteoporosis due to impaired peak bone mass (PBM). Insulin-like growth factor type Ⅰ (IGF-1) levels correlate with the pattern of bone mass accrual and many chronic illnesses are associated with low IGF-1 levels. Reduced serum levels of IGF-1 minimally affect the integrity of the skeleton, whereas recent studies suggest that skeletal IGF-I regulates PBM. To determine the role of IGF-1 in postnatal bone mass accrual regardless of source, we established an inducible type 1 Igf receptor Cre/lox knockout mouse model, in which the type 1 Igf receptor was deleted inducibely in the mesenchymal stem cells (MSCs) from 3-7 weeks of age. The size of the mouse was not affected as knockout and wild type mice had similar body weights and nasoanal and femoral lengths. However, bone volume and trabecular bone thickness were decreased in the secondary spongiosa of female knockout mice relative to wild type controls, indicating that IGF-1 is critical for bone mass. IGF-1 signaling in MSCs in vitro has been implicated to be involved in both migration to the bone surface and differentiation into bone forming osteoblasts. To clarify the exact role of IGF-1 in bone, we found by immunohistochemical analysis that a similar number of Osterix-positive osteoprogenitors were on the bone perimeter, indicating migration of MSCs was not affected. Most importantly, 56% fewer osteocalcin-positive mature osteoblasts were present on the bone perimeter in the secondary spongiosa in knockout mice versus wild type littermates. These in vivo data demonstrate that the primary role of skeletal IGF-1 is for the terminal differentiation of osteoprogenitors, but refute the role of IGF-1 in MSC migration in vivo. Additionally, these findings confirm that impaired IGF-1 signaling in bone MSCs is sufficient to impair bone mass acquisition.展开更多
Microarc oxidation(MAO)is an effective surface treatment method for Ti alloys to allow their application in extreme environments.Here,binary electrolytes consisting of different amounts of sodium phosphate and sodium ...Microarc oxidation(MAO)is an effective surface treatment method for Ti alloys to allow their application in extreme environments.Here,binary electrolytes consisting of different amounts of sodium phosphate and sodium silicate were designed for MAO.The surface morphology,composition,and properties of MAO coatings on Ti-6Al-4V alloy treated in 0.10 mol/L electrolyte were investigated to reveal the effect of PO_(4)^(3-)and SiO_(3)^(2-)ray diffraction,and potentiodynamic polarization.The results showed that PO_(4)^(3-)is beneficial for generating microarcs and forming pores within the coating,resulting in a thick but porous coating.SiO_(3)^(2-)eration of microarcs,resulting in a thin dense coating.The thickness,density,phases content,and polarization resistance of the MAO coatings are primarily affected by the intensity of microarcs for low SiO_(3)^(2-)ciently high.The thickness of MAO coatings obtained in P/Si electrolytes shows a piecewise linear increase with increasing process time during the three stages of microarc discharge.SiO_(3)^(2-)discharge,but slows down the growth of the coating formed in the next stage.展开更多
OBJECTIVE To investigate the pharmacological effect of ursolic acid(UA)on colitis-associated colorectal cancer(CAC)and its underlying mechanism based on the Wnt signaling pathway.METHODS The CAC model in mice was esta...OBJECTIVE To investigate the pharmacological effect of ursolic acid(UA)on colitis-associated colorectal cancer(CAC)and its underlying mechanism based on the Wnt signaling pathway.METHODS The CAC model in mice was established by azoxymethane(AOM)combined and dextran sulfate sodium salt(DSS),accompanied by treatment with various dosages of UA and concomitant appraisal of body weight,stool and physical state of the mice.After the sacrifice of the mice,the tumor and length of the colorectum were measured,followed by retrieval of the liver,spleen,thymus and tumor tissue for downstream assays.The levels of inflammatory factors interleukin-6(IL-6),IL^(-1)βand C-reactive protein(CRP)in the tumor and serum were examined by enzyme-linked immunosorbent assay(ELISA).The pathological changes of colorectal tissues were observed by HE staining.The levels in tumors of Wnt/β-catenin signaling pathway-related proteins Wnt4,GSK-3β,β-catenin,TCF4,LEF1,c-Myc,cyclin D1 and apoptosis-related protein Bcl-2 were assayed by immunohistochemistry(IHC).The mRNA expressions of Wnt4,GSK-3β,β-catenin,TCF4,LEF1,c-Myc,cyclin D1,Bcl-2,Bax,caspase-9 and caspase-3 in tumors were detected by real-time quantitative RT-PCR(RT-qPCR).The protein levels of Wnt4,GSK-3β,β-catenin,TCF4,LEF1,c-Myc,cyclin D1,phospho-β-catenin,phospho-GSK-3β,Bcl-2 and Bax in tumors were probed by analyzed by Western blotting(WB).Also,RNA-seq was employed to assess the gut microbiota in the mice.RESULTS UA significantly ameliorated the symptoms of AOM/DSS-induced mouse CAC,evidenced by improved physical state,body weight,survival rate,colorectal length,the mass of liver,thymus,spleen,and decreased CAC load and colorectal mass.UA attenuated the levels of IL-6,IL^(-1)βand CRP in the mouse serum and colorectal tumor in a dose-dependent manner.HE staining showed that UA lessened carcinogenesis in the colorectum,with lower infiltration of lymphocytes,versus the control.IHC indicated that UA mitigated the expression of Wnt4,β-catenin,TCF4,LEF1,c-Myc,cyclin D1,Bcl-2,and promoted the GSK-3βexpression,compared with the control.Furthermore,UA diminished the mRNA expressions of Wnt4,β-catenin,TCF4,LEF1,c-Myc,cyclin D1,Bcl-2,and heightened the mRNA levels of GSK-3β,caspase-3,capase-9 and Bax in CAC.The results of mRNA expressions were verified by WB analysis,which revealed that UA impeded the protein expression of Wnt4,β-catenin,c-Myc,cyclin D1,Bcl-2,TCF4,LEF1,and elevated the protein levels of GSK-3βand Bax,phospho-β-catenin in mouse CAC.In addition,UA substantially ameliorated the gut microbiota to store the metabolic function in the mice with CAC.CONCLUSION Ursolic acid may protect against CAC,potentially by downregulation of Wnt/β-catenin signaling pathway activity and restoration of gut microbiota.展开更多
A new welding flexible manufacturing cell (WFMC) with intelligent welding sensors was investigated. Based on the analysis of information flow in WFMC, automation Petri net control model has been studied, Which can be...A new welding flexible manufacturing cell (WFMC) with intelligent welding sensors was investigated. Based on the analysis of information flow in WFMC, automation Petri net control model has been studied, Which can be extended to complex welding flexible manufacturing system in the future.展开更多
BACKGROUND Subclavian artery stenosis refers to the stenosis in the lumen caused by the presence of plaque or thrombus in the subclavian artery.It is a common problem in endovascular interventions.In fact,conventional...BACKGROUND Subclavian artery stenosis refers to the stenosis in the lumen caused by the presence of plaque or thrombus in the subclavian artery.It is a common problem in endovascular interventions.In fact,conventional subclavian artery stenting via the femoral artery approach is effective and safe.Nevertheless,because femoral artery puncture is not easy to stop bleeding,it requires longer femoral artery compression or more expensive hemostatic materials,such as staplers.Patients need to be catheterized and bedridden for a longer time,which may lead to many complications,such as pseudoaneurysm.CASE SUMMARY Herein,we reported a new interventional therapy of subclavian artery.From March 1,2020 to August 31,2021,we operated on four patients with subclavian artery stenting via bilateral radial artery access.CONCLUSION After reviewing four cases of successful placement of clavicular artery stents via bilateral radial arteries,we concluded that bilateral radial artery approach is feasible.Clavicular artery stenting is safe,effective,and timesaving.It is an excellent alternative to the traditional femoral artery procedure,with few complications and high comfort degree.展开更多
Convenient non-invasive flow monitoring would facilitate the operation and control in microfluidic chips,but is challenging due to the small space of microchannels and complex operation required in traditional optical...Convenient non-invasive flow monitoring would facilitate the operation and control in microfluidic chips,but is challenging due to the small space of microchannels and complex operation required in traditional optical methods.In this work,we propose a novel non-invasive strategy to probe microfluidic flows via streaming potential phenomenon.By sealing one side of the microchannel with a piece of hydrogel film,streaming potential inside the channel can be clearly detected by electrodes at outer surface of the hydrogel due to ion diffusion in the hydrogel.Flow is detected without sensors contacting with the internal liquid.Moreover,the electrodes shape like a tiny probe,which can move around mapping the flow distribution in a chip with the spatial resolution of 1 mm and flow rate detection limit of 3μL·min–1.Bubbles inside the channels can also be detected,due to the fluctuation of streaming voltage when gas-liquid interface flows through the electrode,showing an easy and potential way for multi-functional flow monitoring in microfluidic chips.展开更多
Stem cell senescence and exhaustion,a hallmark of aging,lead to declines in tissue repair and regeneration in aged individuals.Emerging evidence has revealed that epigenetic regulation plays critical roles in the self...Stem cell senescence and exhaustion,a hallmark of aging,lead to declines in tissue repair and regeneration in aged individuals.Emerging evidence has revealed that epigenetic regulation plays critical roles in the self-renew,lineage-commitment,survival,and function of stem cells.Moreover,epigenetic alterations are considered important drivers of stem cell dysfunction during aging.In this review,we focused on current knowledge of the histone modifications in the aging of mesenchymal stem cells(MSCs).The aberrant epigenetic modifications on histones,including methylation and acetylation,have been found in aging MSCs.By disturbing the expression of specific genes,these epigenetic modifications affect the self-renew,survival,and differentiation of MSCs.A set of epigenetic enzymes that write or erase these modifications are critical in regulating the aging of MSCs.Furthermore,we discussed the rejuvenation strategies based on epigenetics to prevent stem cell aging and/or rejuvenate senescent MSCs.展开更多
Background: Hepatic ischemia-reperfusion injury (HIRI) stands as an unavoidable complication arising from liver surgery, profoundly intertwined with its prognosis. The role of lysine methyltransferase SET domain bifur...Background: Hepatic ischemia-reperfusion injury (HIRI) stands as an unavoidable complication arising from liver surgery, profoundly intertwined with its prognosis. The role of lysine methyltransferase SET domain bifurcated 1 (SETDB1) in HIRI remains elusive, despite its confirmation as a potential therapeutic target for diverse diseases. Here, we investigated the mechanism by which SETDB1 regulated HIRI. Methods: RNA sequencing data were used to identify the expression and potential targets of SETDB1 through bioinformatics analysis. To elucidate the impact of SETDB1 on HIRI, both an in vivo model of HIRI in mice and an in vitro model of hepatocyte hypoxia/reoxygenation were established. Biochemical and histological analyses were used to investigate the influence of SETDB1 on liver damage mediated by HIRI. Chromatin immunoprecipitation and coimmunoprecipitation were implemented to explore the in-depth mechanism of SETDB1 regulating HIRI. Results: We confirmed that hepatocellular SETDB1 was up-regulated during HIRI and had a close correlation with HIRI-related inflammation and apoptosis. Moreover, inhibition of SETDB1 could mitigate HIRI-induced liver damage, inflammation, and apoptosis. Through our comprehensive mechanistic investigation, we revealed that SETDB1 interacts with apoptosis-signal-regulating kinase 1 (ASK1) and facilitates the methylation of its lysine residues. Inhibition of SETDB1 resulted in reduced phosphorylation of ASK1, leading to a marked suppression of downstream c-Jun N-terminal kinase (JNK)/p38 signaling pathway activation. The therapeutic effect on inflammation and apoptosis achieved through SETDB1 inhibition was nullified by the restoration of JNK/p38 signaling activation through ASK1 overexpression. Conclusions: The findings from our study indicate that SETDB1 mediates lysine methylation of ASK1 and modulates the activation of the ASK1–JNK/p38 pathway, thus involved in HIRI-induced inflammation and apoptosis. These results suggest that SETDB1 holds promise as a potential therapeutic target for mitigating HIRI.展开更多
肾移植作为终末期肾病的有效治疗手段,已在世界范围内得到广泛开展。然而,部分患者自身因素可导致移植物功能恢复不佳,甚至导致移植物早期失功。供者特异性抗体(donor specific antibody,DSA)所致抗体介导的排斥反应(antibody-mediated ...肾移植作为终末期肾病的有效治疗手段,已在世界范围内得到广泛开展。然而,部分患者自身因素可导致移植物功能恢复不佳,甚至导致移植物早期失功。供者特异性抗体(donor specific antibody,DSA)所致抗体介导的排斥反应(antibody-mediated rejection,AMR)是移植肾失功的重要原因。DSA主要包括预存DSA和移植后新生DSA,均会影响移植物功能恢复,其中预存DSA是术后超急性排斥反应发生的重要原因,曾被认为是肾移植禁忌证之一,部分尿毒症患者因此失去了肾移植机会。近年来,随着研究的深入和临床经验的积累,很多移植中心对术前DSA阳性受者进行预处理后(如利妥昔单抗清除B细胞、血浆置换清除预存DSA和丙种球蛋白封闭抗体等)再行移植,取得了良好的临床效果[1,2]。本文回顾性分析武汉大学人民医院开展的4例预存DSA阳性肾移植受者资料,并结合相关文献探讨DSA阳性肾移植可行性及处理策略。展开更多
Coronavirus disease 2019(COVID-19)is an infectious disease caused by a newly discovered coronavirus and has rapidly spread to most of the world and resulted in a global pandemic.However,there is a paucity of informati...Coronavirus disease 2019(COVID-19)is an infectious disease caused by a newly discovered coronavirus and has rapidly spread to most of the world and resulted in a global pandemic.However,there is a paucity of information available to characterize the immunodeficient population in the COVID-19 pandemic,especially information that focuses on patients after renal transplantation as the typical representative of this population.展开更多
Oonsider two linear models Xi = U'β + ei, Yj = V1/2y + ηj with response variables missing at random. In this paper, we assume that X, Y are missing at random (MAR) and use the inverse probability weighted imput...Oonsider two linear models Xi = U'β + ei, Yj = V1/2y + ηj with response variables missing at random. In this paper, we assume that X, Y are missing at random (MAR) and use the inverse probability weighted imputation to produce 'complete' data sets for X and Y. Based on these data sets, we construct an empirical likelihood (EL) statistic for the difference of X and Y (denoted as A), and show that the EL statistic has the limiting distribution of X~, which is used to construct a confidence interval for A. Results of a simulation study on the finite sample performance of EL-based confidence intervals on A are reported.展开更多
基金Project supported by the Hunan Provincial Natural Science Foundation of China(Grant No.2021JJ30738)Scientific Research Fund of Hunan Provincial Education Department(Grant No.19K001)Hunan Provincial Key Laboratory of Flexible Electronic Materials Genome Engineering’s Open Fund Project-2020(Grant No.202016)。
文摘A novel 4H-Si C trench insulated gate bipolar transistor(IGBT)with a controllable hole-extracting(CHE)path is proposed and investigated in this paper.The CHE path is controlled by metal semiconductor gate(MES gate)and metal oxide semiconductor gate(MOS gate)in the p-shield region.The grounded p-shield region can significantly suppress the high electric field around gate oxide in Si C devices,but it weakens the conductivity modulation in the Si C trench IGBT by rapidly sweeping out holes.This effect can be eliminated by introducing the CHE path.The CHE path is pinched off by the high gate bias voltage at on-state to maintain high conductivity modulation and obtain a comparatively low on-state voltage(VON).During the turn-off transient,the CHE path is formed,which contributes to a decreased turn-off loss(EOFF).Based on numerical simulation,the EOFFof the proposed IGBT is reduced by 89%compared with the conventional IGBT at the same VONand the VONof the proposed IGBT is reduced by 50%compared to the grounded p-shield IGBT at the same EOFF.In addition,the average power reduction for the proposed device can be 51.0%to 81.7%and 58.2%to 72.1%with its counterparts at a wide frequency range of 500 Hz to 10 k Hz,revealing a great improvement of frequency characteristics.
基金provided by K01-AR060433 (T.Q.)K08-AR064833 (J.C)R01-AR063943 (X.C)
文摘Parathyroid hormone(PTH) regulates bone remodeling by activating PTH type 1 receptor(PTH1R) in osteoblasts/osteocytes. Insulinlike growth factor type 1(IGF-1) stimulates mesenchymal stem cell differentiation to osteoblasts. However, little is known about the signaling mechanisms that regulates the osteoblast-to-osteocyte transition. Here we report that PTH and IGF-I synergistically enhance osteoblast-to-osteocyte differentiation. We identified that a specific tyrosine residue, Y494, on the cytoplasmic domain of PTH1R can be phosphorylated by insulin-like growth factor type I receptor(IGF1R) in vitro. Phosphorylated PTH1R localized to the barbed ends of actin filaments and increased actin polymerization during morphological change of osteoblasts into osteocytes.Disruption of the phosphorylation site reduced actin polymerization and dendrite length. Mouse models with conditional ablation of PTH1R in osteoblasts demonstrated a reduction in the number of osteoctyes and dendrites per osteocyte, with complete overlap of PTH1R with phosphorylated-PTH1R positioning in osteocyte dendrites in wild-type mice. Thus, our findings reveal a novel signaling mechanism that enhances osteoblast-to-osteocyte transition by direct phosphorylation of PTH1R by IGF1R.
基金supported in part by the grants from the United States National Institute of Health NIDDK including T32DK07751 (JLC)the Diabetes Research and Training Center grant P60DK079637(JSF),and DK057501 and DK08098 (XC)
文摘Survival of children with chronic medical illnesses is leading to an increase in secondary osteoporosis due to impaired peak bone mass (PBM). Insulin-like growth factor type Ⅰ (IGF-1) levels correlate with the pattern of bone mass accrual and many chronic illnesses are associated with low IGF-1 levels. Reduced serum levels of IGF-1 minimally affect the integrity of the skeleton, whereas recent studies suggest that skeletal IGF-I regulates PBM. To determine the role of IGF-1 in postnatal bone mass accrual regardless of source, we established an inducible type 1 Igf receptor Cre/lox knockout mouse model, in which the type 1 Igf receptor was deleted inducibely in the mesenchymal stem cells (MSCs) from 3-7 weeks of age. The size of the mouse was not affected as knockout and wild type mice had similar body weights and nasoanal and femoral lengths. However, bone volume and trabecular bone thickness were decreased in the secondary spongiosa of female knockout mice relative to wild type controls, indicating that IGF-1 is critical for bone mass. IGF-1 signaling in MSCs in vitro has been implicated to be involved in both migration to the bone surface and differentiation into bone forming osteoblasts. To clarify the exact role of IGF-1 in bone, we found by immunohistochemical analysis that a similar number of Osterix-positive osteoprogenitors were on the bone perimeter, indicating migration of MSCs was not affected. Most importantly, 56% fewer osteocalcin-positive mature osteoblasts were present on the bone perimeter in the secondary spongiosa in knockout mice versus wild type littermates. These in vivo data demonstrate that the primary role of skeletal IGF-1 is for the terminal differentiation of osteoprogenitors, but refute the role of IGF-1 in MSC migration in vivo. Additionally, these findings confirm that impaired IGF-1 signaling in bone MSCs is sufficient to impair bone mass acquisition.
基金financially supported by China Postdoctoral Science Foundation (No.2021M700569)Chongqing Postdoctoral Science Foundation (No.cstc2021jcyj-bsh0133)
文摘Microarc oxidation(MAO)is an effective surface treatment method for Ti alloys to allow their application in extreme environments.Here,binary electrolytes consisting of different amounts of sodium phosphate and sodium silicate were designed for MAO.The surface morphology,composition,and properties of MAO coatings on Ti-6Al-4V alloy treated in 0.10 mol/L electrolyte were investigated to reveal the effect of PO_(4)^(3-)and SiO_(3)^(2-)ray diffraction,and potentiodynamic polarization.The results showed that PO_(4)^(3-)is beneficial for generating microarcs and forming pores within the coating,resulting in a thick but porous coating.SiO_(3)^(2-)eration of microarcs,resulting in a thin dense coating.The thickness,density,phases content,and polarization resistance of the MAO coatings are primarily affected by the intensity of microarcs for low SiO_(3)^(2-)ciently high.The thickness of MAO coatings obtained in P/Si electrolytes shows a piecewise linear increase with increasing process time during the three stages of microarc discharge.SiO_(3)^(2-)discharge,but slows down the growth of the coating formed in the next stage.
基金National Natural Science Foundation of China(81573813,81173598)Sichuan Provincial Admin⁃istration of Traditional Chinese Medicine of China(2021MS447)+1 种基金Excellent Talent Program of Chengdu University of Tra⁃ditional Chinese Medicine of China(YXRC2019002,ZRYY1917)Open Research Fund of the State Key Laboratory of Southwestern Chinese Medicine Resources of China(2020XSGG006)。
文摘OBJECTIVE To investigate the pharmacological effect of ursolic acid(UA)on colitis-associated colorectal cancer(CAC)and its underlying mechanism based on the Wnt signaling pathway.METHODS The CAC model in mice was established by azoxymethane(AOM)combined and dextran sulfate sodium salt(DSS),accompanied by treatment with various dosages of UA and concomitant appraisal of body weight,stool and physical state of the mice.After the sacrifice of the mice,the tumor and length of the colorectum were measured,followed by retrieval of the liver,spleen,thymus and tumor tissue for downstream assays.The levels of inflammatory factors interleukin-6(IL-6),IL^(-1)βand C-reactive protein(CRP)in the tumor and serum were examined by enzyme-linked immunosorbent assay(ELISA).The pathological changes of colorectal tissues were observed by HE staining.The levels in tumors of Wnt/β-catenin signaling pathway-related proteins Wnt4,GSK-3β,β-catenin,TCF4,LEF1,c-Myc,cyclin D1 and apoptosis-related protein Bcl-2 were assayed by immunohistochemistry(IHC).The mRNA expressions of Wnt4,GSK-3β,β-catenin,TCF4,LEF1,c-Myc,cyclin D1,Bcl-2,Bax,caspase-9 and caspase-3 in tumors were detected by real-time quantitative RT-PCR(RT-qPCR).The protein levels of Wnt4,GSK-3β,β-catenin,TCF4,LEF1,c-Myc,cyclin D1,phospho-β-catenin,phospho-GSK-3β,Bcl-2 and Bax in tumors were probed by analyzed by Western blotting(WB).Also,RNA-seq was employed to assess the gut microbiota in the mice.RESULTS UA significantly ameliorated the symptoms of AOM/DSS-induced mouse CAC,evidenced by improved physical state,body weight,survival rate,colorectal length,the mass of liver,thymus,spleen,and decreased CAC load and colorectal mass.UA attenuated the levels of IL-6,IL^(-1)βand CRP in the mouse serum and colorectal tumor in a dose-dependent manner.HE staining showed that UA lessened carcinogenesis in the colorectum,with lower infiltration of lymphocytes,versus the control.IHC indicated that UA mitigated the expression of Wnt4,β-catenin,TCF4,LEF1,c-Myc,cyclin D1,Bcl-2,and promoted the GSK-3βexpression,compared with the control.Furthermore,UA diminished the mRNA expressions of Wnt4,β-catenin,TCF4,LEF1,c-Myc,cyclin D1,Bcl-2,and heightened the mRNA levels of GSK-3β,caspase-3,capase-9 and Bax in CAC.The results of mRNA expressions were verified by WB analysis,which revealed that UA impeded the protein expression of Wnt4,β-catenin,c-Myc,cyclin D1,Bcl-2,TCF4,LEF1,and elevated the protein levels of GSK-3βand Bax,phospho-β-catenin in mouse CAC.In addition,UA substantially ameliorated the gut microbiota to store the metabolic function in the mice with CAC.CONCLUSION Ursolic acid may protect against CAC,potentially by downregulation of Wnt/β-catenin signaling pathway activity and restoration of gut microbiota.
基金The National Natural Science FOundation of China under grant No.59635160 supports this work.
文摘A new welding flexible manufacturing cell (WFMC) with intelligent welding sensors was investigated. Based on the analysis of information flow in WFMC, automation Petri net control model has been studied, Which can be extended to complex welding flexible manufacturing system in the future.
文摘BACKGROUND Subclavian artery stenosis refers to the stenosis in the lumen caused by the presence of plaque or thrombus in the subclavian artery.It is a common problem in endovascular interventions.In fact,conventional subclavian artery stenting via the femoral artery approach is effective and safe.Nevertheless,because femoral artery puncture is not easy to stop bleeding,it requires longer femoral artery compression or more expensive hemostatic materials,such as staplers.Patients need to be catheterized and bedridden for a longer time,which may lead to many complications,such as pseudoaneurysm.CASE SUMMARY Herein,we reported a new interventional therapy of subclavian artery.From March 1,2020 to August 31,2021,we operated on four patients with subclavian artery stenting via bilateral radial artery access.CONCLUSION After reviewing four cases of successful placement of clavicular artery stents via bilateral radial arteries,we concluded that bilateral radial artery approach is feasible.Clavicular artery stenting is safe,effective,and timesaving.It is an excellent alternative to the traditional femoral artery procedure,with few complications and high comfort degree.
基金supported by the National Natural Science Foundation of China(Grant Nos.51976141,52006123,62161160311).
文摘Convenient non-invasive flow monitoring would facilitate the operation and control in microfluidic chips,but is challenging due to the small space of microchannels and complex operation required in traditional optical methods.In this work,we propose a novel non-invasive strategy to probe microfluidic flows via streaming potential phenomenon.By sealing one side of the microchannel with a piece of hydrogel film,streaming potential inside the channel can be clearly detected by electrodes at outer surface of the hydrogel due to ion diffusion in the hydrogel.Flow is detected without sensors contacting with the internal liquid.Moreover,the electrodes shape like a tiny probe,which can move around mapping the flow distribution in a chip with the spatial resolution of 1 mm and flow rate detection limit of 3μL·min–1.Bubbles inside the channels can also be detected,due to the fluctuation of streaming voltage when gas-liquid interface flows through the electrode,showing an easy and potential way for multi-functional flow monitoring in microfluidic chips.
基金supported by grants from the National Key Research and Development Program of China(No.2021YFA1100603)the National Natural Science Foundation of China(No.32271365,81600912 and 82071092)+2 种基金the Technology Innovation Research and Development Project of Chengdu,China(2022-YF05-01388-SN)the Key Project of Sichuan province,China(No.2020YFS0177 and 2019YFS0311)the Fundamental Research Funds for the Central Universities(China)(No.YJ201878).
文摘Stem cell senescence and exhaustion,a hallmark of aging,lead to declines in tissue repair and regeneration in aged individuals.Emerging evidence has revealed that epigenetic regulation plays critical roles in the self-renew,lineage-commitment,survival,and function of stem cells.Moreover,epigenetic alterations are considered important drivers of stem cell dysfunction during aging.In this review,we focused on current knowledge of the histone modifications in the aging of mesenchymal stem cells(MSCs).The aberrant epigenetic modifications on histones,including methylation and acetylation,have been found in aging MSCs.By disturbing the expression of specific genes,these epigenetic modifications affect the self-renew,survival,and differentiation of MSCs.A set of epigenetic enzymes that write or erase these modifications are critical in regulating the aging of MSCs.Furthermore,we discussed the rejuvenation strategies based on epigenetics to prevent stem cell aging and/or rejuvenate senescent MSCs.
基金Financial support for this study was provided by the National Natural Science Foundation of China(grant nos.81870067 and 82170664).
文摘Background: Hepatic ischemia-reperfusion injury (HIRI) stands as an unavoidable complication arising from liver surgery, profoundly intertwined with its prognosis. The role of lysine methyltransferase SET domain bifurcated 1 (SETDB1) in HIRI remains elusive, despite its confirmation as a potential therapeutic target for diverse diseases. Here, we investigated the mechanism by which SETDB1 regulated HIRI. Methods: RNA sequencing data were used to identify the expression and potential targets of SETDB1 through bioinformatics analysis. To elucidate the impact of SETDB1 on HIRI, both an in vivo model of HIRI in mice and an in vitro model of hepatocyte hypoxia/reoxygenation were established. Biochemical and histological analyses were used to investigate the influence of SETDB1 on liver damage mediated by HIRI. Chromatin immunoprecipitation and coimmunoprecipitation were implemented to explore the in-depth mechanism of SETDB1 regulating HIRI. Results: We confirmed that hepatocellular SETDB1 was up-regulated during HIRI and had a close correlation with HIRI-related inflammation and apoptosis. Moreover, inhibition of SETDB1 could mitigate HIRI-induced liver damage, inflammation, and apoptosis. Through our comprehensive mechanistic investigation, we revealed that SETDB1 interacts with apoptosis-signal-regulating kinase 1 (ASK1) and facilitates the methylation of its lysine residues. Inhibition of SETDB1 resulted in reduced phosphorylation of ASK1, leading to a marked suppression of downstream c-Jun N-terminal kinase (JNK)/p38 signaling pathway activation. The therapeutic effect on inflammation and apoptosis achieved through SETDB1 inhibition was nullified by the restoration of JNK/p38 signaling activation through ASK1 overexpression. Conclusions: The findings from our study indicate that SETDB1 mediates lysine methylation of ASK1 and modulates the activation of the ASK1–JNK/p38 pathway, thus involved in HIRI-induced inflammation and apoptosis. These results suggest that SETDB1 holds promise as a potential therapeutic target for mitigating HIRI.
文摘肾移植作为终末期肾病的有效治疗手段,已在世界范围内得到广泛开展。然而,部分患者自身因素可导致移植物功能恢复不佳,甚至导致移植物早期失功。供者特异性抗体(donor specific antibody,DSA)所致抗体介导的排斥反应(antibody-mediated rejection,AMR)是移植肾失功的重要原因。DSA主要包括预存DSA和移植后新生DSA,均会影响移植物功能恢复,其中预存DSA是术后超急性排斥反应发生的重要原因,曾被认为是肾移植禁忌证之一,部分尿毒症患者因此失去了肾移植机会。近年来,随着研究的深入和临床经验的积累,很多移植中心对术前DSA阳性受者进行预处理后(如利妥昔单抗清除B细胞、血浆置换清除预存DSA和丙种球蛋白封闭抗体等)再行移植,取得了良好的临床效果[1,2]。本文回顾性分析武汉大学人民医院开展的4例预存DSA阳性肾移植受者资料,并结合相关文献探讨DSA阳性肾移植可行性及处理策略。
基金This work is funded by a Key Project of Health and Family Planning Commission of Hubei Province of China(No.WJ2019Z007)the National Key Research&Development Program of China(2018YFA0108804)+3 种基金the National Natural Science Foundation of China(Nos.81970650 and 81770753)the Youth Program of National Natural Science Foundation of China(No.81800661)the Fundamental Research Funds for the Central Universities(No.20ykpy34)the China Postdoctoral Science Foundation Funded Project(No.2020M683083).
文摘Coronavirus disease 2019(COVID-19)is an infectious disease caused by a newly discovered coronavirus and has rapidly spread to most of the world and resulted in a global pandemic.However,there is a paucity of information available to characterize the immunodeficient population in the COVID-19 pandemic,especially information that focuses on patients after renal transplantation as the typical representative of this population.
基金Supported by the National Natural Science Foundation of China(No.11271088,11361011,11201088)Natural Science Foundation of Guangxi(No.2013GXNSFAA(019004 and 019007),2013GXNSFBA019001)
文摘Oonsider two linear models Xi = U'β + ei, Yj = V1/2y + ηj with response variables missing at random. In this paper, we assume that X, Y are missing at random (MAR) and use the inverse probability weighted imputation to produce 'complete' data sets for X and Y. Based on these data sets, we construct an empirical likelihood (EL) statistic for the difference of X and Y (denoted as A), and show that the EL statistic has the limiting distribution of X~, which is used to construct a confidence interval for A. Results of a simulation study on the finite sample performance of EL-based confidence intervals on A are reported.