BACKGROUND:During bone tissue healing,promoting the vascularization of new bone is a common strategy to accelerate the repair of bone tissue.However,the rapid fibrosis process during bone defect repair is often ignored.OBJECTIVE:To design and prepare a core-shell structure bionic scaffold to regulate the process of fibrosis and vascularization in new callus,characterize physical characteristics of the scaffold,and verify the anti-fibrosis and osteogenic properties in vitro and in vivo.METHODS:A core-shell structure bionic scaffold to regulate the process of fibrosis and vascularization in new callus was designed and prepared.The outer shell structure of the scaffold was composed of polycaprolactone electrospun nanofibers loaded with fibroblast activating protein inhibitor;and the inner core structure was composed of gelatin methacrylate hydrogel loaded with deferoxamine.The physical characteristics of electrospun and hydrogel were characterized,and the biocompatibility of the material was verified by live-dead staining and CCK-8 assay.The antifibrotic effect of core-shell structure was analyzed by fibroblast in vitro assay.The osteogenic effect of fibroblast activating protein inhibitor in core-shell structure was analyzed by MC3T3-E1 cells in vitro assay.The vasogenic effect of deferoxamine in core-shell structure was analyzed by human umbilical vein endothelial cells.The effect of bionic core-shell scaffold on bone repair was evaluated by critical bone defect test in rats.RESULTS AND CONCLUSION:(1)The core-shell structure bionic scaffold had good biocompatibility.Hydrophobic polycaprolactone electrospun fibers prepared by electrospinning technology could effectively block the ingrowth of exogenous fibrous tissue on the physical level.The electrospun fiber membrane could effectively release the anti-fibrosis drug fibroblast activating protein inhibitor within 2 weeks,and the released anti-fibrosis drug could inhibit the growth and adhesion of fibroblasts around bone defects,effectively reduced the expression of fibroblast-related proteins,promoted the expression of osteoblast protein in MC3T3-E1 cells,and accelerated its mineralization rate.The deferoxamine in the core-shell structure could promote the migration and vascular formation ability of human umbilical vein endothelial cells,and promoted their strong expression of"H"vascular characteristic protein.(2)In critical bone defect model of SD rats established in the femur,compared with polycaprolactone membrane,the core-shell structure bionic scaffold could effectively repair bone defects.(3)These findings indicate that the core-shell structure bionic scaffold can prevent excessive fibrosis of callus and promote the formation of"H"vessels in the new callus,which can effectively avoid the occurrence of nonunion and accelerate the repair process of critical bone defect.

BACKGROUND:Cell senescence is one of the major risk factors for osteoarthritis,but there is no widely accepted anti-osteoarthritis therapy targeting senescent cells.OBJECTIVE:To develop a feasible treatment strategy targeting senescent cells in osteoarthritis.METHODS:The cationic liposome containing rapamycin,RAPA@Lipo,was prepared by thin film dispersion method.Methylallylated hyaluronic acid hydrogel was synthesized,and RAPA@Lipo was added to the methylallylated hyaluronic acid hydrogel aqueous phase solution.The hydrogel microspheres were prepared by microfluidic equipment.Solid hydrogel microspheres(RAPA@Lipo@MS)were crosslinked under violet light.Primary human chondrocytes were co-cultured with RAPA@Lipo and RAPA@Lipo@MS,respectively.The biocompatibility of the materials was evaluated by CCK-8 assay and live/dead staining.Primary rat chondrocytes were cultured in four groups.Normal control group was cultured for 48 hours.The model group was stimulated with H2O2 for 24 hours to establish senescent cell model.RAPA@Lipo group and RAPA@Lipo@MS group were cultured for 24 hours after establishing senescent cell model with RAPA@Lipo and RAPA@Lipo@MS,respectively.After culture,immunofluorescence was used to observe the expression of p62 and type Ⅱ collagen.RT-PCR was used to detect the mRNA expression of interleukin 6,matrix metalloproteinase 13,type Ⅱ collagen,aggrecan,and ADAMTS-5.RESULTS AND CONCLUSION:(1)The results of CCK-8 assay and live/dead staining showed that RAPA@Lipo and RAPA@Lipo@MS had good biocompatibility.(2)Compared with the normal control group,the protein expression of p62 was increased(P<0.05);the expression of type Ⅱ collagen was decreased(P<0.05),and the mRNA expression levels of interleukin 6,matrix metalloproteinase 13,and ADAMTS-5 were increased(P<0.05);mRNA expression levels of type Ⅱ collagen and aggrecan were decreased(P<0.05)in the model group.Compared with the model group,the expression of p62 protein was decreased(P<0.05);the expression of type Ⅱ collagen was increased(P<0.05),and the mRNA expression levels of interleukin 6,matrix metalloproteinase 13,and ADAMTS-5 were decreased(P<0.05);mRNA expression of type Ⅱ collagen and aggrecan increased(P<0.05)in the RAPA@Lipo@MS group.(3)These findings indicate that RAPA@Lipo@MS can control the quality of cells in vivo by enhancing autophagy,reduce senescent cells in vivo,and locally eliminate senescent cells and senescence-associated secretory phenotype factors in osteoarthritis,thereby slowing the progression of osteoarthritis and creating a cartilage microenvironment that promotes regeneration.

Objective To explore the perioperative therapeutic effects and follow-up manage-ment in 16 patients with left ventricular assist device(LVAD)implantation.Methods A retrospec-tive analysis was conducted in data of 16 patients who underwent LVAD implantation in the depart-ment of cardiovascular surgery.Data of 6-minute walk test(6MWT),European Quality of Life-5 Di-mension-5 Levels(EQ-5D-5L),New York Heart Association(NYHA)classification,echocardio-graphy,chest radiography,cardiothoracic ratio,and occurrence of complications(infection,bleed-ing,thrombosis,right heart failure,neurological issues)were collected via the electronic medical re-cord system before surgery and at 30,60,and 90 days postoperatively.Results All patients sur-vived with the pump at 90 days postoperatively.One patient with preoperative renal insufficiency un-derwent dialysis and received a heart transplant after 8 months.One patient developed a sterile granu-loma at the percutaneous lead site on the abdominal wall,which improved after treatment,no complica-tions occurred in other patients.At 90 days postoperatively,there was no statistically significant differ-ence in the right ventricular area change fraction and tricuspid annular plane systolic excursion com-pared with preoperative values(P＞0.05).The left ventricular ejection fraction,left ventricular end-diastolic diameter,and cardiothoracic ratio showed significant improvement compared with preoperative levels(P＜0.05).At 30 days postoperatively,30％of patients recovered to NYHA class Ⅰ and 70％to class Ⅱ;at 60 days,80％of patients to class Ⅰ and 20％to class Ⅱ;at 90 days,90％to classⅠ and 10％to class Ⅱ.The 6MWT and EQ-5D-5L scores of patients significantly increased within 90 days postoperatively(P＜0.01).Conclusion Through rigorous preoperative assessment by a multidisciplinary LVAD team,refinement of surgical techniques,and comprehensive management during hospitalization,self-management before discharge,daily follow-up after discharge,and fol-low-up management upon returning to the hospital for patients with LVAD implantation,the cardiac function and quality of life of patients are significantly improved at 90 days postoperatively.

The occurrence and development of atherosclerotic cardiovascular diseases is closely related to abnormally elevated plasma low density lipoprotein cholesterol(LDLC)level.Low density lipoprotein receptor(LDLR)plays a central role in the maintenance of cholesterol homeostasis by mediating the endocytotic clearance of LDLC,and the abundance of LDLR on the surface of the cell membrane is closely related to the expression level and recirculation of LD-LR.Recent studies have found that RING-E3 ubiquitin ligase can regulate LDLR levels through a dual mechanism:on the one hand,it directly ubiquitinates and modifies LDLR to promote its degradation via the endosome-lysosome pathway;on the other hand,it reduces LDLR synthesis through activation of the liver X receptor(LXR)pathway or inhibition of the nuclear translocation of sterol regulatory element-binding protein(SREBP).Together,these two mechanisms lead to a decrease in cell membrane LDLR abundance,impairing cholesterol metabolic homeostasis and exacerbating LDLC accumu-lation.Therefore,targeted inhibition of RING-E3 ubiquitin ligase activity may be a novel strategy to regulate LDLR ex-pression,reduce plasma LDLC levels,and combat cardiovascular disease.This article reviews the mechanism of action of RING-E3 ubiquitin ligase in regulating LDLR and its related research progress.

Objective To investigate whether Yiqicongming Decoction(YCD)can alleviate dry eye syndrome in rats.Methods Thirty-six male SD rats at 6 weeks of age were divided into blank group,model group,positive group,YCD high-dose group,YCD medium-dose group,and YCD low-dose group,with six rats in each group.The rats underwent iris,tear secretion volume,and corneal epithelial damage scoring assessments.Conjunctival tissue was stained with PAS,and the activity of superoxide dismutase(SOD)and the content of malondialdehyde(MDA)were detected using the en-zyme-linked immunosorbent assay(ELISA).The level of reactive oxygen species(ROS)was measured by flow cytometry.Western blot was used to detect the protein expression of nuclear factor erythroid 2-related factor 2(Nrf2)and hymeoxyge-nase-1(HO-1)in corneal tissues.Results Compared with the blank group,the number of goblet cells in the conjuncti-va,corneal epithelial injury score,MDA content and ROS level in the model group were significantly increased at all time points(all P＜0.05).The tear secretion volume of rats decreased on days 3,7,and 14,and the number of conjunctival goblet cells and SOD activity also decreased(all P＜0.05).Compared with the model group,the conjunctival score,corne-al epithelial injury score,MDA content,and ROS level in the positive control group and high-,medium-,and low-dose YCD groups were significantly reduced(all P＜0.05),while SOD activity and protein expression levels of Nrf2 and HO-1 in rats on day 14 were significantly increased(all P＜0.05).Compared with the high-dose YCD group,the conjunctival score,corneal epithelial injury score,and ROS level in the low-and medium-dose YCD groups were significantly increased(all P＜0.05),while SOD activity and protein expression levels of Nrf2 and HO-1 on day 14 were significantly decreased(all P＜0.05).On day 14,the tear secretion volume and the number of goblet cells in the conjunctiva of rats administered a low dose of Yiqi Congming Decoction both decreased(all P＜0.05).Compared with the medium-dose YCD group,the conjunc-tival score,corneal epithelial injury score and ROS level in the low-dose YCD group were significantly increased(all P＜0.05),while the tear secretion volume and protein expression levels of Nrf2 and HO-1 on day 14 were significantly de-creased(all P＜0.05).Conclusion YCD can increase tear secretion,alleviate iris and corneal epithelial damage,acti-vate Nrf2/HO-1 pathway,regulate oxidative stress,and alleviate dry eye syndrome.

The occurrence and development of atherosclerotic cardiovascular diseases is closely related to abnormally elevated plasma low density lipoprotein cholesterol(LDLC)level.Low density lipoprotein receptor(LDLR)plays a central role in the maintenance of cholesterol homeostasis by mediating the endocytotic clearance of LDLC,and the abundance of LDLR on the surface of the cell membrane is closely related to the expression level and recirculation of LD-LR.Recent studies have found that RING-E3 ubiquitin ligase can regulate LDLR levels through a dual mechanism:on the one hand,it directly ubiquitinates and modifies LDLR to promote its degradation via the endosome-lysosome pathway;on the other hand,it reduces LDLR synthesis through activation of the liver X receptor(LXR)pathway or inhibition of the nuclear translocation of sterol regulatory element-binding protein(SREBP).Together,these two mechanisms lead to a decrease in cell membrane LDLR abundance,impairing cholesterol metabolic homeostasis and exacerbating LDLC accumu-lation.Therefore,targeted inhibition of RING-E3 ubiquitin ligase activity may be a novel strategy to regulate LDLR ex-pression,reduce plasma LDLC levels,and combat cardiovascular disease.This article reviews the mechanism of action of RING-E3 ubiquitin ligase in regulating LDLR and its related research progress.

BACKGROUND:During bone tissue healing,promoting the vascularization of new bone is a common strategy to accelerate the repair of bone tissue.However,the rapid fibrosis process during bone defect repair is often ignored.OBJECTIVE:To design and prepare a core-shell structure bionic scaffold to regulate the process of fibrosis and vascularization in new callus,characterize physical characteristics of the scaffold,and verify the anti-fibrosis and osteogenic properties in vitro and in vivo.METHODS:A core-shell structure bionic scaffold to regulate the process of fibrosis and vascularization in new callus was designed and prepared.The outer shell structure of the scaffold was composed of polycaprolactone electrospun nanofibers loaded with fibroblast activating protein inhibitor;and the inner core structure was composed of gelatin methacrylate hydrogel loaded with deferoxamine.The physical characteristics of electrospun and hydrogel were characterized,and the biocompatibility of the material was verified by live-dead staining and CCK-8 assay.The antifibrotic effect of core-shell structure was analyzed by fibroblast in vitro assay.The osteogenic effect of fibroblast activating protein inhibitor in core-shell structure was analyzed by MC3T3-E1 cells in vitro assay.The vasogenic effect of deferoxamine in core-shell structure was analyzed by human umbilical vein endothelial cells.The effect of bionic core-shell scaffold on bone repair was evaluated by critical bone defect test in rats.RESULTS AND CONCLUSION:(1)The core-shell structure bionic scaffold had good biocompatibility.Hydrophobic polycaprolactone electrospun fibers prepared by electrospinning technology could effectively block the ingrowth of exogenous fibrous tissue on the physical level.The electrospun fiber membrane could effectively release the anti-fibrosis drug fibroblast activating protein inhibitor within 2 weeks,and the released anti-fibrosis drug could inhibit the growth and adhesion of fibroblasts around bone defects,effectively reduced the expression of fibroblast-related proteins,promoted the expression of osteoblast protein in MC3T3-E1 cells,and accelerated its mineralization rate.The deferoxamine in the core-shell structure could promote the migration and vascular formation ability of human umbilical vein endothelial cells,and promoted their strong expression of"H"vascular characteristic protein.(2)In critical bone defect model of SD rats established in the femur,compared with polycaprolactone membrane,the core-shell structure bionic scaffold could effectively repair bone defects.(3)These findings indicate that the core-shell structure bionic scaffold can prevent excessive fibrosis of callus and promote the formation of"H"vessels in the new callus,which can effectively avoid the occurrence of nonunion and accelerate the repair process of critical bone defect.

Objective To investigate whether Yiqicongming Decoction(YCD)can alleviate dry eye syndrome in rats.Methods Thirty-six male SD rats at 6 weeks of age were divided into blank group,model group,positive group,YCD high-dose group,YCD medium-dose group,and YCD low-dose group,with six rats in each group.The rats underwent iris,tear secretion volume,and corneal epithelial damage scoring assessments.Conjunctival tissue was stained with PAS,and the activity of superoxide dismutase(SOD)and the content of malondialdehyde(MDA)were detected using the en-zyme-linked immunosorbent assay(ELISA).The level of reactive oxygen species(ROS)was measured by flow cytometry.Western blot was used to detect the protein expression of nuclear factor erythroid 2-related factor 2(Nrf2)and hymeoxyge-nase-1(HO-1)in corneal tissues.Results Compared with the blank group,the number of goblet cells in the conjuncti-va,corneal epithelial injury score,MDA content and ROS level in the model group were significantly increased at all time points(all P＜0.05).The tear secretion volume of rats decreased on days 3,7,and 14,and the number of conjunctival goblet cells and SOD activity also decreased(all P＜0.05).Compared with the model group,the conjunctival score,corne-al epithelial injury score,MDA content,and ROS level in the positive control group and high-,medium-,and low-dose YCD groups were significantly reduced(all P＜0.05),while SOD activity and protein expression levels of Nrf2 and HO-1 in rats on day 14 were significantly increased(all P＜0.05).Compared with the high-dose YCD group,the conjunctival score,corneal epithelial injury score,and ROS level in the low-and medium-dose YCD groups were significantly increased(all P＜0.05),while SOD activity and protein expression levels of Nrf2 and HO-1 on day 14 were significantly decreased(all P＜0.05).On day 14,the tear secretion volume and the number of goblet cells in the conjunctiva of rats administered a low dose of Yiqi Congming Decoction both decreased(all P＜0.05).Compared with the medium-dose YCD group,the conjunc-tival score,corneal epithelial injury score and ROS level in the low-dose YCD group were significantly increased(all P＜0.05),while the tear secretion volume and protein expression levels of Nrf2 and HO-1 on day 14 were significantly de-creased(all P＜0.05).Conclusion YCD can increase tear secretion,alleviate iris and corneal epithelial damage,acti-vate Nrf2/HO-1 pathway,regulate oxidative stress,and alleviate dry eye syndrome.

BACKGROUND:Cell senescence is one of the major risk factors for osteoarthritis,but there is no widely accepted anti-osteoarthritis therapy targeting senescent cells.OBJECTIVE:To develop a feasible treatment strategy targeting senescent cells in osteoarthritis.METHODS:The cationic liposome containing rapamycin,RAPA@Lipo,was prepared by thin film dispersion method.Methylallylated hyaluronic acid hydrogel was synthesized,and RAPA@Lipo was added to the methylallylated hyaluronic acid hydrogel aqueous phase solution.The hydrogel microspheres were prepared by microfluidic equipment.Solid hydrogel microspheres(RAPA@Lipo@MS)were crosslinked under violet light.Primary human chondrocytes were co-cultured with RAPA@Lipo and RAPA@Lipo@MS,respectively.The biocompatibility of the materials was evaluated by CCK-8 assay and live/dead staining.Primary rat chondrocytes were cultured in four groups.Normal control group was cultured for 48 hours.The model group was stimulated with H2O2 for 24 hours to establish senescent cell model.RAPA@Lipo group and RAPA@Lipo@MS group were cultured for 24 hours after establishing senescent cell model with RAPA@Lipo and RAPA@Lipo@MS,respectively.After culture,immunofluorescence was used to observe the expression of p62 and type Ⅱ collagen.RT-PCR was used to detect the mRNA expression of interleukin 6,matrix metalloproteinase 13,type Ⅱ collagen,aggrecan,and ADAMTS-5.RESULTS AND CONCLUSION:(1)The results of CCK-8 assay and live/dead staining showed that RAPA@Lipo and RAPA@Lipo@MS had good biocompatibility.(2)Compared with the normal control group,the protein expression of p62 was increased(P<0.05);the expression of type Ⅱ collagen was decreased(P<0.05),and the mRNA expression levels of interleukin 6,matrix metalloproteinase 13,and ADAMTS-5 were increased(P<0.05);mRNA expression levels of type Ⅱ collagen and aggrecan were decreased(P<0.05)in the model group.Compared with the model group,the expression of p62 protein was decreased(P<0.05);the expression of type Ⅱ collagen was increased(P<0.05),and the mRNA expression levels of interleukin 6,matrix metalloproteinase 13,and ADAMTS-5 were decreased(P<0.05);mRNA expression of type Ⅱ collagen and aggrecan increased(P<0.05)in the RAPA@Lipo@MS group.(3)These findings indicate that RAPA@Lipo@MS can control the quality of cells in vivo by enhancing autophagy,reduce senescent cells in vivo,and locally eliminate senescent cells and senescence-associated secretory phenotype factors in osteoarthritis,thereby slowing the progression of osteoarthritis and creating a cartilage microenvironment that promotes regeneration.

Objective:To explore the application of photoplethysmography (iPPG) for contactless vital signs monitoring in the intensive care unit (ICU).Methods:Ten tracheostomy patients in intensive care had their heart rate, oxygen saturation, and diastolic and systolic pressures monitored using iPPG technology and a 24-hour bedside monitor. The readings included periods at rest, during turning, during suctioning, and when undergoing vigorous physical therapy and occupational therapy. The monitoring lasted 3 consecutive days. The data collected by the two methods were compared to analyze the accuracy of the contactless vital signs monitoring system.Results:The oxygen saturation readings of the two systems showed no significant differences. The heart rates, diastolic pressures, and systolic pressures did, however, differ significantly.Conclusions:In the situations tested, contactless monitoring of oxygen saturation is effective, but there is still significant room for improvement in the three indicators of heart rate, systolic pressure, and diastolic pressure.