One of the most prevalent disorders that cause blindness worldwide is cataract,and its essence is the visual disorder caused by the opacity of the lens.The significant degree of variation in cataracts and the fact tha...One of the most prevalent disorders that cause blindness worldwide is cataract,and its essence is the visual disorder caused by the opacity of the lens.The significant degree of variation in cataracts and the fact that a variety of factors can impact a patient’s lens transparency make it especially crucial to investigate the pathogenesis of cataracts at the molecular level.It has been found that more than 60 genes are linked to the formation of cataracts,and the construction of a transgenic mouse model of cataract similar to the selection of human lens clouding due to a variety of causes has become an important means of studying the pathogenesis of cataract.Therefore,the research on the application of transgenic mice to the molecular pathogenesis of cataracts will be the main topic of this review of the literature.展开更多
This paper summarizes the feasibility of constructing the recommended reading system in the library of high medical college, andanalyzes the core technology-recommendation algorithm in the recommendation system. At th...This paper summarizes the feasibility of constructing the recommended reading system in the library of high medical college, andanalyzes the core technology-recommendation algorithm in the recommendation system. At the same time, it introduces the innovative design ofthe recommendation model of the recommendation system of high medical institutions. Based on the local data to promote the implementation ofthe model, the domestic library to provide recommended services to the future made a prospect.展开更多
A preliminary miRNA screening showed that expression levels of rno-miRNA-27a-3p were significantly increased in the serum and brain tissues of rats undergoing cerebral ischemia.In recent years,there is evidence of the...A preliminary miRNA screening showed that expression levels of rno-miRNA-27a-3p were significantly increased in the serum and brain tissues of rats undergoing cerebral ischemia.In recent years,there is evidence of the protective capacity of the saponins extracted from panax ginseng and its primary active ingredient ginsenosideRg1oncerebral ischemic injury.Methods:Fetal rat neurons(FRNs)were cultured in glucose-and-serumfree medium and exposed to hypoxia to establish a cerebral ischemia model in vitro(oxygen and glucose deprivation model,OGD).Antioxidant indexes(CAT,SOD),inflammatory markers(MPO,TNF-αand IL-6),and the expression of apoptosis and proliferation associated proteins(NF kB-p65,Caspase 3-cleaved,BCL-2)were examined.Results:Pre-treatment of Rg1(30–100μg/mL)could effectively inhibit the decline of antioxidant indexes(CAT,SOD)and increase in inflammatory markers(MPO,TNF-αand IL-6),and effectively inhibited the apoptosis in FRNs induced by OGD in a gradient-dependent manner.The mechanism analysis showed that the role of Rg1 in protecting against ischemia-induced neuron damage depends on its indirect up-regulation of PPAR protein via suppression of rnomiRNA-27a-3p.Moreover,these effects of Rg1 could be reversed by exogenous rno-miRNA-27a-3p and PPAR gene silencing in FRNs exposed to OGD.Conclusion:To summarize,our study demonstrates that Rg1 could effectively attenuate neuronal damage caused by cerebral ischemia via the rno-miRNA-27a-3p/PPARγpathway.Further,clarification of the novel mechanism will certainly improve our previous understanding of the role of Rg1 and enhancing its level in treatments for alleviating ischemic brain injury.展开更多
Against the backdrop of the global COVID-19 pandemic,the teaching and management of clinical medical interns have been facing tremendous challenges.When interns majoring in clinical medicine enter the internship posit...Against the backdrop of the global COVID-19 pandemic,the teaching and management of clinical medical interns have been facing tremendous challenges.When interns majoring in clinical medicine enter the internship position,they lack self-protection awareness and have limited ability to respond to unexpected public health events.This article explores the cognitive situation,existing problems,and improvement measures of clinical medical interns in the post-epidemic era.Therefore,this article proposes a series of improvement measures,including strengthening epidemic training and education for interns,enhancing personal protective awareness,and lastly achieving the role transition from intern to doctor.展开更多
Among the various treatment methods for stroke, increasing attention has been paid to tradi- tional Chinese medicines. Buyang Huanwu decoction is a commonly used traditional Chinese medicine for the treatment of strok...Among the various treatment methods for stroke, increasing attention has been paid to tradi- tional Chinese medicines. Buyang Huanwu decoction is a commonly used traditional Chinese medicine for the treatment of stroke. This paper summarizes the active components of the Chinese herb, which is composed of Huangqi （Radix Astragali seu Hedysari）, Danggui （Radix Angelica sinensis）, Chishao （Radix Paeoniae Rubra）, Chuanxiong （Rhizoma Ligustici Chuanx- iong）, Honghua （Flos Carthami）, Taoren （Semen Persicae） and Dilong （Pheretima）, and identifies the therapeutic targets and underlying mechanisms that contribute to the neuroprotective prop- erties of Buyang Huanwu decoction.展开更多
Ligustrazine （2,3,5,6-tetramethylpyrazine） is a major active ingredient of the Szechwan lovage rhizome and is extensively used in treatment of ischemic cerebrovascular disease. The mecha- nism of action of ligustraz...Ligustrazine （2,3,5,6-tetramethylpyrazine） is a major active ingredient of the Szechwan lovage rhizome and is extensively used in treatment of ischemic cerebrovascular disease. The mecha- nism of action of ligustrazine use against ischemic cerebrovascular diseases remains unclear at present. This study summarizes its protective effect, the optimum time window of administra- tion, and the most effective mode of administration for clinical treatment of cerebral ischemia/ reperfusion injury. We examine the effects of ligustrazine on suppressing excitatory amino acid release, promoting migration, differentiation and proliferation of endogenous neural stem cells. We also looked at its effects on angiogenesis and how it inhibits thrombosis, the inflammatory response, and apoptosis after cerebral ischemia. We consider that ligustrazine gives noticeable protection from cerebral ischemia/reperfusion injury. The time window of ligustrazine admin- istration is limited. The protective effect and time window of a series of derivative monomers of ligustrazine such as 2-[（1,1-dimethylethyl）oxidoimino]methyl]-3,5,6-trimethylpyrazine, CXC137 and CXC 195 after cerebral ischemia were better than ligustrazine.展开更多
Rat models of focal cerebral ischemia/reperfusion injury were established by occlusion of the middle cerebral artery. Microarray analysis showed that 24 hours after cerebral ischemia, there were nine up-regulated and ...Rat models of focal cerebral ischemia/reperfusion injury were established by occlusion of the middle cerebral artery. Microarray analysis showed that 24 hours after cerebral ischemia, there were nine up-regulated and 27 down-regulated microRNA genes in cortical tissue. Bioinformatic analysis showed that bcl-2 was the target gene of microRNA-384-5p and microRNA-494, and caspase-3 was the target gene of microRNA-129, microRNA-320 and microRNA-326. Real-time PCR and western blot analyses showed that 24 hours after cerebral ischemia, bcl-2 mRNA and protein levels in brain tissue were significantly decreased, while caspase-3 mRNA and protein levels were significantly increased. This suggests that following cerebral ischemia, differentially expressed microRNA-384-5p, microRNA-494, microRNA-320, microRNA-129 and microRNA-326 can regulate bcl-2 and caspase-3 expression in brain tissue.展开更多
AIM:To investigate the expressions of type I collagen, α2 integrin and β1 integrin in the posterior sclera of guinea pigs with defocus myopia and whether basic fibroblast growth factor (bFGF) injection inhibits the ...AIM:To investigate the expressions of type I collagen, α2 integrin and β1 integrin in the posterior sclera of guinea pigs with defocus myopia and whether basic fibroblast growth factor (bFGF) injection inhibits the formation and development of myopia by upregulating the expression of type I collagen, α2 integrin and β1 integrin. METHODS:After 14 days of treatment, the refractive state and axial length were measured and the levels of type I collagen, α2 integrin and β1 integrin were assayed in the posterior sclerae of groups of guinea pigs that wore a monocular-7D polymethylmethacrylate (PMMA) lens or had -7D lens wear followed by the peribulbar injection of Phosphate Buffer Solution (PBS) or bFGF. The untreated fellow eye served as a control. Guinea pigs with no treatment served as normal group. ·RESULTS:The results showed that 14 days of monocular defocus increased axial eye length and refraction, while bFGF delivery inhibited them markedly. Further, it was also found that the monocular-7D lens could decrease the levels of type I collagen, α2 integrin and β1 integrin expressions, while, unlike PBS, bFGF increased them significantly in comparison to contralateral control eyes and normal eyes. CONCLUSION:bFGF can prevent the formation anddevelopment of defocus myopia by upregulating the expressions of type I collagen, α2 integrin and β1 integrin. Taken together, our results demonstrate that bFGF promotes sclera remodeling to prevent myopia in guinea pigs.展开更多
Objective：To test the effects of salidroside on formation and growth of glioma together with tumor microenvironment.Methods：Salidroside extracted from Rhodiola rosea was purified and treated on human glioma cells U2...Objective：To test the effects of salidroside on formation and growth of glioma together with tumor microenvironment.Methods：Salidroside extracted from Rhodiola rosea was purified and treated on human glioma cells U251 at the concentration of 20 μg/mL.3-（4,5-dimethylthiazol-2-yl）-2,5-dephenyltetrazolium bromide （MTT） assay for cytotoxicity and flow cytometry （FCM） for cell cycle analysis were performed.Then for in vivo study,xenotransplantation tumor model in nude mice was generated and treated with salidroside at the concentration of 50 mg/kg.d for totally 20 d.Body weight and tumor size were detected every 2 d after the treatment.The levels of 8-isoprostane,superoxide dismutase （SOD） and malondialdehyde （MDA）,special markers for oxidative stress,were detected while immunofluoresence staining was performed for astrocyte detection.Results：For in vitro study,salidroside could decrease the viability of human glioma cells U251 and the growth of U251 cells at G0/G1 checkpoint during the cell cycle.For in vivo study,salidroside could also inhibit the growth of human glioma tissue in nude mice.The body weight of these nude mice treated with salidroside did not decrease as quickly as control group.In the tumor xenotransplantation nude mice model,mice were found of inhibition of oxidative stress by detection of biomarkers.Furthermore,overgrowth of astrocytes due to the stimulation of oxidative stress in the cortex of brain was inhibited after the treatment of salidroside.Conclusions：Salidroside could inhibit the formation and growth of glioma both in vivo and in vitro and improve the tumor microenvironment via inhibition of oxidative stress and astrocytes.展开更多
Human Wharton＇s jelly mesenchymal stem cells were isolated from fetal umbilical cord. Cells were cultured in serumfree neural stem cellconditioned medium or neural stem cellconditioned medium supplemented with Dkk1, ...Human Wharton＇s jelly mesenchymal stem cells were isolated from fetal umbilical cord. Cells were cultured in serumfree neural stem cellconditioned medium or neural stem cellconditioned medium supplemented with Dkk1, a Wnt/13 catenin pathway antagonist, and LeftyA, a Nodal signaling pathway antagonist to induce differentiation into retinal progenitor cells. Inverted microscopy showed that after induction, the spindleshaped or fibroblastlike Wharton＇s jelly mesenchymal stem cells changed into bulbous cells with numerous processes. Immunofluorescent cytochemical stain ing and reversetranscription PCR showed positive expression of retinal progenitor cell markers, Pax6 and Rx, as well as weakly downregulated nestin expression. These results demonstrate that Wharton＇s jelly mesenchymal stem cells are capable of differentiating into retinal progenitor cells in vitro.展开更多
The objective of the present study was to investigate the effects of genistein and equol on 3β-hydroxysteroid de- hydrogenase （3β-HSD） and 17β-hydroxysteroid dehydrogenase 3 （17β-HSD3） in human and rat testis ...The objective of the present study was to investigate the effects of genistein and equol on 3β-hydroxysteroid de- hydrogenase （3β-HSD） and 17β-hydroxysteroid dehydrogenase 3 （17β-HSD3） in human and rat testis microsomes. These enzymes （3β-HSD and 17β-HSD3）, along with two others （cytochrome P450 side-chain cleavage enzyme and cytochrome P450 17α-hydroxylase/17-20 lyase）, catalyze the reactions that convert the steroid cholesterol into the sex hormone testosterone. Genistein inhibited 3β-HSD activity （0.2 μmol L^-1 pregnenolone） with half-maximal inhibition or a half-maximal inhibitory concentration （IC50） of 87 ± 15 （human） and 636 ± 155 nmol L^-1 （rat）. Genistein＇s mode of action on 3β-HSD activity was competitive for the substrate pregnenolonrge and noncompetitive for the cofactor NAD＋. There was no difference in genistein＇s potency of 3β-HSD inhibition between intact rat Leydig cells and testis microsomes. In contrast to its potent inhibition of 3β-HSD, genistein had lesser effects on human and rat 17β-HSD3 （0.1 μmol L^-1 androstenedione）, with an IC50 〉 100μmol L^-1. On the other hand, equol only inhibited human 3β-HSD by 42%, and had no effect on 3β-HSD and 17β-HSD3 in rat tissues. These observations imply that the ability of soy isoflavones to regulate androgen biosynthesis in Leydig cells is due in part to action on Leydig cell 3β- HSD activity. Given the increasing intake of soy-based food products and their potential effect on blood androgen levels, these findings are greatly relevant to public health.展开更多
Animal and clinical studies have confirmed the therapeutic effect of bone marrow mesenchymal stem cells on cerebral ischemia, but their mechanisms of action remain poorly understood. Here, we summarize the transplanta...Animal and clinical studies have confirmed the therapeutic effect of bone marrow mesenchymal stem cells on cerebral ischemia, but their mechanisms of action remain poorly understood. Here, we summarize the transplantation approaches, directional migration, differentiation, replacement, neural circuit reconstruction,angiogenesis, neurotrophic factor secretion, apoptosis, immunomodulation, multiple mechanisms of action,and optimization strategies for bone marrow mesenchymal stem cells in the treatment of ischemic stroke.We also explore the safety of bone marrow mesenchymal stem cell transplantation and conclude that bone marrow mesenchymal stem cell transplantation is an important direction for future treatment of cerebral ischemia. Determining the optimal timing and dose for the transplantation are important directions for future research.展开更多
The rapidly increasing prevalence of cognitive impairment and Alzheimer＇s disease has the potential to create a major worldwide healthcare crisis. Structural MRI studies in patients with Alzheimer＇s disease and mild...The rapidly increasing prevalence of cognitive impairment and Alzheimer＇s disease has the potential to create a major worldwide healthcare crisis. Structural MRI studies in patients with Alzheimer＇s disease and mild cognitive impairment are currently attracting considerable interest. It is extremely important to study early structural and metabolic changes, such as those in the hippocampus, entorhinal cortex, and gray matter structures in the medial temporal lobe, to allow the early detection of mild cognitive impairment and AIzheimer＇s disease. The microstructural integrity of white matter can be studied with diffusion tensor imaging. Increased mean diffusivity and decreased fractional anisotropy are found in subjects with white matter damage. Functional imaging studies with positron emission tomography tracer compounds enable detection of amyloid plaques in the living brain in patients with Alzheimer＇s disease. In this review, we will focus on key findings from brain imaging studies in mild cognitive impairment and Alzheimer＇s disease, including structural brain changes studied with MRI and white matter changes seen with diffusion tensor imaging, and other specific imaging methodologies will also be discussed.展开更多
AIM: To investigate the expression and role of activin A in a mouse model of acute chemical liver injury. METHODS: Acute liver injury in C57BL/6 male mice was induced by intraperitoneal injection with carbon tetrachlo...AIM: To investigate the expression and role of activin A in a mouse model of acute chemical liver injury. METHODS: Acute liver injury in C57BL/6 male mice was induced by intraperitoneal injection with carbon tetrachloride (CCl4 ) (0.5 mL/kg, body weight) dissolved in olive oil (1:19 v/v). Mice were sacrificed 1, 3, 5 and 7 d after the treatment. The levels of alanine aminotrans-ferase (ALT) and aspartate aminotransferase (AST) in serum were examined and pathological changes of liver observed by hematoxylin and eosin staining to evaluate the liver injury. Activin A protein levels in serum and hepatic tissue homogenate of mice were detected by enzyme-linked immunosorbent assay, and the expres-sion pattern of activin A protein in livers of mice was examined by immunohistochemistry. Activin type Ⅱ A receptor (ActRⅡA) and Smad3 expressions in the liver were analyzed by real-time quantitative reverse transcription-polymerase chain reaction. In order to further investigate the role of activin A, we also utilized activin A blocking experiment by anti-activin A antibody (500 μg/kg, body weight) injection into mouse tail vein. RESULTS: In CCl4-treated mice, serum ALT and AST levels were significantly increased, compared with that in control mice (P<0.01). Furthermore, the serious necrosis was observed around hepatic portal areas in CCl4-treated mice. Simultaneously, activin A levels in serum and hepatic tissue homogenate of mice treated with CCl4 for 1, 3 and 5 d increased significantly, com-pared with that in control mice (P<0.01). Activin A protein expression in hepatocytes not within the ne-crotic area was also upregulated in mice following CCl4 treatment. Not only activin A, but also ActRⅡA and activin signaling molecule Smad3 mRNA expressions in injury liver induced by CCl4 were significantly higher than that in control liver. In addition, levels of serum ALT and AST in CCl4-treated mice were significantly decreased by injection of anti-activin A antibody to block endogenous activin A action, compared with that in CCl4-treated mice by injection of immunoglobulin G instead of anti-activin A antibody (P<0.01), and the severity of liver injury was also reduced remarkably. CONCLUSION: These data show that activin A is in-volved in CCl4-induced acute liver injury. Blocking ac-tivin A actions may be a therapeutic approach for acute liver injury.展开更多
Chemical investigation of Syringa velutina Kom. led to the isolation of two new secoiridoid glucosides. Their structures were identified as 6＇-O-（6, 7-dihyrofoliamenthoyl）-8-epi-longisidic acid （syrveoside A, 1） ...Chemical investigation of Syringa velutina Kom. led to the isolation of two new secoiridoid glucosides. Their structures were identified as 6＇-O-（6, 7-dihyrofoliamenthoyl）-8-epi-longisidic acid （syrveoside A, 1） and 6＇-O-menthiafoloyl-8-epi-ldngisidic acid （syrveoside B, 2） on the basis of chemical and physicochemical evidence.展开更多
Selectins are carbohydrate-binding cell adhesion molecules that play a major role in the initiation of inflammatory responses. Accumulaed evidence has suggested that heparin＇s anti-inflammatory effects are mainly med...Selectins are carbohydrate-binding cell adhesion molecules that play a major role in the initiation of inflammatory responses. Accumulaed evidence has suggested that heparin＇s anti-inflammatory effects are mainly mediated by blocking L-or P-selectin-initiated cell adhesion. Recently, we have reported that periodate-oxidized, borohydridereduced heparin （RO-heparln） can inhibit P-selectin-mediated acute inflammation. Here we further examined the effect of RO-heparin on the adhesion of L-selectin-mediated leukocytes to vascular endothelium under flow conditions in vivo and in vitro. The results show that RO-heparin with a low anticoagulant activity can effectively reduce leucocyte roiling on thioglycoUate-induced rat mesenterlc venules and L-selectin-metadiated neutrophil roiling on TNF-α-induced human umbilical vein endothelial cells（HUVECs） under flow conditions. Our findings suggest that the effect of RO-heparin on inflammatory responses is mainly a result of its inhibiting the interaction between P- or L-selectin and its ligands. The findings also suggest that RO-heparin may be useful in preventing inflammation diseases.展开更多
OBJECTIVE： The study was undertaken to explore a bibliometric approach to quantitatively assess the research on detection of monosialoganglioside from 2002 to 2011. DATA RETRIEVAL： A bibliometric analysis based on t...OBJECTIVE： The study was undertaken to explore a bibliometric approach to quantitatively assess the research on detection of monosialoganglioside from 2002 to 2011. DATA RETRIEVAL： A bibliometric analysis based on the publications on Web of Science was performed using key words such as ＂monosialoganglioside＂, ＂colloidal gold＂, ＂high performance liquid chromatography＂ and ＂detection＂. SELECTION CRITERIA： （1） Research articles on the detection of monosialoganglioside; （2） researches on human and animal fundamentals, clinical trials and case reports; （3） article types： article, review, proceedings paper, note, letter, editorial material, discussion, book chapter; （4） Publication year： 2002-2011. Exclusion criteria： （1） unrelated articles; （2） type of articles： correction; （3） articles from following databases： all databases related to social science and arts ＆ humanities in Web of Science were excluded. MAIN OUTCOME MEASURES： （1） distribution of subject areas; （2） number of publications annually; （3） document type and language of publications; （4） distribution of institutions; （5） distribution of output in journals; （6） the number of countries in which the article is published; （7） top cited paper. RESULTS： Overall population stands at 1 880 research articles addressing detection of monosialoganglioside in Web of Science during the study period. Articles （1 599） were the most frequently used document type comprising 85.05%, followed by meeting abstracts, reviews and proceedings papers. The distribution of subject categories showed that monosialoganglioside research covered both clinical and basic science research. The USA, Japan, and Italy were the three most productive countries, and the publication numbers in the USA were highest with 559 papers. The University of Milan, Nagoya University, and Kinki University are the most productive institutions regarding detection of monosialoganglioside. In 559 articles published by Americans, Medical College of Georgia ranked the first with 30 articles, followed by University of Medicine and Dentistry of New Jersey （28 articles）, Cornell University （24 articles） and Johns Hopkins University （24 articles）. In 442 articles published by Japanese, Nagoya University ranked the first with 40 articles, followed by Kinki University （36 articles）, and Dokkyo University （31 articles）. Though the total number of publications by Japanese is smaller than Americans, the top three institutions published more publications than American institutions. There is a markedly increase in the number of publications on the subject detection of monosialoganglioside in 2004, which the peak in the past 10 years. The valley bottom of the subject appeared in 2005. In total, the research is increased with time prolonged. Journal of Neurochemistry, Journal of Biological Chemistry and Journal of Neuroimmunology were core subject journals in monosialoganglioside studies. CONCLUSION： This study highlights the topics in detection of monosialoganglioside research that are being published around the world.展开更多
The Al-doped Ni2P/AI-SBA-15 catalyst with high hydrodeoxygenation （HDO） activity was synthesized by tem- perature programmed reduction at a relatively low reduction temperature of 400 ℃. The as-prepared catalyst wa...The Al-doped Ni2P/AI-SBA-15 catalyst with high hydrodeoxygenation （HDO） activity was synthesized by tem- perature programmed reduction at a relatively low reduction temperature of 400 ℃. The as-prepared catalyst was characterized by X-ray diffraction （XRD）, H2 temperature-programmed reduction （H2-TPR）, X-ray photoelectron spectroscopy （XPS）, transmission electron microscope （TEM）, NH3 temperature programmed desorption （NH3-TPD）, N2 adsorption-desorption and CO uptake. The effect of AI on benzofuran （BF） HDO performance was investigated. The result indicates that the incorporation of AI into the SBA-15 support can promote the formation of much uniform, smaller, highly dispersed N2P particles on the catalyst. The AI also contrib- utes to suppress the enrichment of P and promote more exposed Ni sites on the surface. In addition, the incorporation of AI can enhance the acid strength. The total deoxygenated product yield over Ni2P/AI-SBA-15 reached 90.3%, which is an increase of 19.4%, when compared with that found for Ni2P/SBA-15 （70.9%）.展开更多
A moving-mass control method is introduced to stratospheric airship for its special working condition of low atmospheric density and low speed.The dynamic equation of airship is derived by using the Newton-Euler metho...A moving-mass control method is introduced to stratospheric airship for its special working condition of low atmospheric density and low speed.The dynamic equation of airship is derived by using the Newton-Euler method and the mechanism of attitude control by moving masses is studied.Then the passive gliding of airship by the moving masses is given based on the theory of glider,and attitude control capability between moving mass and elevator is compared at different airspeed.Analysis results show that the motion of masses changes the gravity center of the airship system,which makes the inertia tensor and the gravity moment vary.Meanwhile,the aerodynamic angles are generated,which results in the change of aerodynamic moment.Control efficiency of moving masses is independent of airspeed.Thus the moving-mass control has the advantage over the aerodynamic surfaces at low airspeed.展开更多
Our previous study has shown that the transcription factor Krüppel-like factor 7(KLF7) promotes peripheral nerve regeneration and motor function recovery after spinal cord injury.KLF7 also participates in traumat...Our previous study has shown that the transcription factor Krüppel-like factor 7(KLF7) promotes peripheral nerve regeneration and motor function recovery after spinal cord injury.KLF7 also participates in traumatic brain injury,but its regulatory mechanisms remain poorly understood.In the present study,an HT22 cell model of traumatic brain injury was established by stretch injury and oxygenglucose deprivation.These cells were then transfected with an adeno-associated virus carrying KLF7(AAV-KLF7).The results revealed that,after stretch injury and oxygen-glucose deprivation,KLF7 greatly reduced apoptosis,activated caspase-3 and lactate dehydrogenase,downregulated the expression of the apoptotic markers B-cell lymphoma 2(Bcl-2)-associated X protein(Bax) and cleaved caspase-3,and increased the expression of βIII-tubulin and the antiapoptotic marker Bcl-2.Furthermore,KLF7 overexpression upregulated Janus kinase 2(JAK2) and signal transducer and activator of transcription 3(STAT3) phosphorylation in HT22 cells treated by stretch injury and oxygenglucose deprivation.Immunoprecipitation assays revealed that KLF7 directly participated in the phosphorylation of STAT3.In addition,treatment with AG490,a selective inhibitor of JAK2/STAT3,weakened the protective effects of KLF7.A mouse controlled cortical impact model of traumatic brain injury was then established.At 30 minutes before modeling,AAV-KLF7 was injected into the ipsilateral lateral ventricle.The protein and m RNA levels of KLF7 in the hippocampus were increased at 1 day after injury and recovered to normal levels at 3 days after injury.KLF7 reduced ipsilateral hippocampal atrophy,decreased the injured cortex volume,downregulated Bax and cleaved caspase-3 expression,and increased the number of 5-bromo-2'-deoxyuridine-positive neurons and Bcl-2 protein expression.Moreover,KLF7 transfection greatly enhanced the phosphorylation of JAK2 and STAT3 in the ipsilateral hippocampus.These results suggest that KLF7 may protect hippocampal neurons after traumatic brain injury through activation of the JAK2/STAT3 signaling pathway.The study was approved by the Institutional Review Board of Mudanjiang Medical University,China(approval No.mdjyxy-2018-0012) on March 6,2018.展开更多
基金Supported by the National Natural Science Foundation of China(No.82271070)the Heilongjiang Provincial Undergraduate Colleges and Universities Central to Support the Reform and Development of Local Colleges and Universities(No.2020YQ08)+1 种基金the Natural Science Foundation Project of Heilongjiang Province(Key Project/Outstanding Youth/Joint Guidance,No.LH2021H112)Doctoral Research Fund of Mudanjiang Medical University Affiliated Hongqi Hospital(No.2024-HQBS-03).
文摘One of the most prevalent disorders that cause blindness worldwide is cataract,and its essence is the visual disorder caused by the opacity of the lens.The significant degree of variation in cataracts and the fact that a variety of factors can impact a patient’s lens transparency make it especially crucial to investigate the pathogenesis of cataracts at the molecular level.It has been found that more than 60 genes are linked to the formation of cataracts,and the construction of a transgenic mouse model of cataract similar to the selection of human lens clouding due to a variety of causes has become an important means of studying the pathogenesis of cataract.Therefore,the research on the application of transgenic mice to the molecular pathogenesis of cataracts will be the main topic of this review of the literature.
文摘This paper summarizes the feasibility of constructing the recommended reading system in the library of high medical college, andanalyzes the core technology-recommendation algorithm in the recommendation system. At the same time, it introduces the innovative design ofthe recommendation model of the recommendation system of high medical institutions. Based on the local data to promote the implementation ofthe model, the domestic library to provide recommended services to the future made a prospect.
基金supported by the National Natural Science Foundation of China,Nos.81973317,81374007,81870977the Natural Science Foundation of Heilongjiang Province,HL2019H062+1 种基金the Projects of Basic Scientific Research Business Expenses in Higher Education Institutions of Heilongjiang Province,No.2018-KYYWF-MY-005the Students Innovative and the Entrepreneurship Training Scientific Research Foundation of Heilongjiang Province,No.102292017001.
文摘A preliminary miRNA screening showed that expression levels of rno-miRNA-27a-3p were significantly increased in the serum and brain tissues of rats undergoing cerebral ischemia.In recent years,there is evidence of the protective capacity of the saponins extracted from panax ginseng and its primary active ingredient ginsenosideRg1oncerebral ischemic injury.Methods:Fetal rat neurons(FRNs)were cultured in glucose-and-serumfree medium and exposed to hypoxia to establish a cerebral ischemia model in vitro(oxygen and glucose deprivation model,OGD).Antioxidant indexes(CAT,SOD),inflammatory markers(MPO,TNF-αand IL-6),and the expression of apoptosis and proliferation associated proteins(NF kB-p65,Caspase 3-cleaved,BCL-2)were examined.Results:Pre-treatment of Rg1(30–100μg/mL)could effectively inhibit the decline of antioxidant indexes(CAT,SOD)and increase in inflammatory markers(MPO,TNF-αand IL-6),and effectively inhibited the apoptosis in FRNs induced by OGD in a gradient-dependent manner.The mechanism analysis showed that the role of Rg1 in protecting against ischemia-induced neuron damage depends on its indirect up-regulation of PPAR protein via suppression of rnomiRNA-27a-3p.Moreover,these effects of Rg1 could be reversed by exogenous rno-miRNA-27a-3p and PPAR gene silencing in FRNs exposed to OGD.Conclusion:To summarize,our study demonstrates that Rg1 could effectively attenuate neuronal damage caused by cerebral ischemia via the rno-miRNA-27a-3p/PPARγpathway.Further,clarification of the novel mechanism will certainly improve our previous understanding of the role of Rg1 and enhancing its level in treatments for alleviating ischemic brain injury.
基金Heilongjiang Province Higher Education Teaching Reform Project Application Form“Research on the Demand for Epidemic Prevention Teaching for Intern Doctors During the New Coronavirus Epidemic”(Project number:SJGY20200756)Key topics of Heilongjiang Province’s“14th Five-Year Plan”for Educational Science in 2023“Research Applying the BOPPPS Teaching Model Based on Job Competency in Practical Endotracheal Intubation Skills”(Project number:GJB1423364)。
文摘Against the backdrop of the global COVID-19 pandemic,the teaching and management of clinical medical interns have been facing tremendous challenges.When interns majoring in clinical medicine enter the internship position,they lack self-protection awareness and have limited ability to respond to unexpected public health events.This article explores the cognitive situation,existing problems,and improvement measures of clinical medical interns in the post-epidemic era.Therefore,this article proposes a series of improvement measures,including strengthening epidemic training and education for interns,enhancing personal protective awareness,and lastly achieving the role transition from intern to doctor.
基金supported by grants from Health and Family Planning Commission of Heilongjiang Province Research Projects,No. 2014-195Science and Technology Research Projects of Mudanjiang Medical University,No.ZS201305.
文摘Among the various treatment methods for stroke, increasing attention has been paid to tradi- tional Chinese medicines. Buyang Huanwu decoction is a commonly used traditional Chinese medicine for the treatment of stroke. This paper summarizes the active components of the Chinese herb, which is composed of Huangqi （Radix Astragali seu Hedysari）, Danggui （Radix Angelica sinensis）, Chishao （Radix Paeoniae Rubra）, Chuanxiong （Rhizoma Ligustici Chuanx- iong）, Honghua （Flos Carthami）, Taoren （Semen Persicae） and Dilong （Pheretima）, and identifies the therapeutic targets and underlying mechanisms that contribute to the neuroprotective prop- erties of Buyang Huanwu decoction.
基金supported by a grant from the Health and Family Planning Commission of Heilongjiang Province Research Project in China,No.2014-195the Education Department Science and Technology Foundation of Heilongjiang Province in China,No.12531741the Natural Science Foundation of Heilongjiang Province of China,No.H2015083
文摘Ligustrazine （2,3,5,6-tetramethylpyrazine） is a major active ingredient of the Szechwan lovage rhizome and is extensively used in treatment of ischemic cerebrovascular disease. The mecha- nism of action of ligustrazine use against ischemic cerebrovascular diseases remains unclear at present. This study summarizes its protective effect, the optimum time window of administra- tion, and the most effective mode of administration for clinical treatment of cerebral ischemia/ reperfusion injury. We examine the effects of ligustrazine on suppressing excitatory amino acid release, promoting migration, differentiation and proliferation of endogenous neural stem cells. We also looked at its effects on angiogenesis and how it inhibits thrombosis, the inflammatory response, and apoptosis after cerebral ischemia. We consider that ligustrazine gives noticeable protection from cerebral ischemia/reperfusion injury. The time window of ligustrazine admin- istration is limited. The protective effect and time window of a series of derivative monomers of ligustrazine such as 2-[（1,1-dimethylethyl）oxidoimino]methyl]-3,5,6-trimethylpyrazine, CXC137 and CXC 195 after cerebral ischemia were better than ligustrazine.
基金supported by the National Natural Science Foundation of China,No.30973897the Natural Science Foundation of Heilongjiang Province,No.D200978the Postgraduate Innovative Scientific Research Foundation of Heilongjiang Province,No.YJSCX2011-286HLJ
文摘Rat models of focal cerebral ischemia/reperfusion injury were established by occlusion of the middle cerebral artery. Microarray analysis showed that 24 hours after cerebral ischemia, there were nine up-regulated and 27 down-regulated microRNA genes in cortical tissue. Bioinformatic analysis showed that bcl-2 was the target gene of microRNA-384-5p and microRNA-494, and caspase-3 was the target gene of microRNA-129, microRNA-320 and microRNA-326. Real-time PCR and western blot analyses showed that 24 hours after cerebral ischemia, bcl-2 mRNA and protein levels in brain tissue were significantly decreased, while caspase-3 mRNA and protein levels were significantly increased. This suggests that following cerebral ischemia, differentially expressed microRNA-384-5p, microRNA-494, microRNA-320, microRNA-129 and microRNA-326 can regulate bcl-2 and caspase-3 expression in brain tissue.
文摘AIM:To investigate the expressions of type I collagen, α2 integrin and β1 integrin in the posterior sclera of guinea pigs with defocus myopia and whether basic fibroblast growth factor (bFGF) injection inhibits the formation and development of myopia by upregulating the expression of type I collagen, α2 integrin and β1 integrin. METHODS:After 14 days of treatment, the refractive state and axial length were measured and the levels of type I collagen, α2 integrin and β1 integrin were assayed in the posterior sclerae of groups of guinea pigs that wore a monocular-7D polymethylmethacrylate (PMMA) lens or had -7D lens wear followed by the peribulbar injection of Phosphate Buffer Solution (PBS) or bFGF. The untreated fellow eye served as a control. Guinea pigs with no treatment served as normal group. ·RESULTS:The results showed that 14 days of monocular defocus increased axial eye length and refraction, while bFGF delivery inhibited them markedly. Further, it was also found that the monocular-7D lens could decrease the levels of type I collagen, α2 integrin and β1 integrin expressions, while, unlike PBS, bFGF increased them significantly in comparison to contralateral control eyes and normal eyes. CONCLUSION:bFGF can prevent the formation anddevelopment of defocus myopia by upregulating the expressions of type I collagen, α2 integrin and β1 integrin. Taken together, our results demonstrate that bFGF promotes sclera remodeling to prevent myopia in guinea pigs.
基金supported by the National Natural Science Foundation of China(No.81141080)Jiangsu Provincial Natural Science Foundation(SBK201340596)
文摘Objective：To test the effects of salidroside on formation and growth of glioma together with tumor microenvironment.Methods：Salidroside extracted from Rhodiola rosea was purified and treated on human glioma cells U251 at the concentration of 20 μg/mL.3-（4,5-dimethylthiazol-2-yl）-2,5-dephenyltetrazolium bromide （MTT） assay for cytotoxicity and flow cytometry （FCM） for cell cycle analysis were performed.Then for in vivo study,xenotransplantation tumor model in nude mice was generated and treated with salidroside at the concentration of 50 mg/kg.d for totally 20 d.Body weight and tumor size were detected every 2 d after the treatment.The levels of 8-isoprostane,superoxide dismutase （SOD） and malondialdehyde （MDA）,special markers for oxidative stress,were detected while immunofluoresence staining was performed for astrocyte detection.Results：For in vitro study,salidroside could decrease the viability of human glioma cells U251 and the growth of U251 cells at G0/G1 checkpoint during the cell cycle.For in vivo study,salidroside could also inhibit the growth of human glioma tissue in nude mice.The body weight of these nude mice treated with salidroside did not decrease as quickly as control group.In the tumor xenotransplantation nude mice model,mice were found of inhibition of oxidative stress by detection of biomarkers.Furthermore,overgrowth of astrocytes due to the stimulation of oxidative stress in the cortex of brain was inhibited after the treatment of salidroside.Conclusions：Salidroside could inhibit the formation and growth of glioma both in vivo and in vitro and improve the tumor microenvironment via inhibition of oxidative stress and astrocytes.
基金supported by 2010 Com-advanced School Young Diaph Support Project of Heilongjiang Province,China, No. 1155G60
文摘Human Wharton＇s jelly mesenchymal stem cells were isolated from fetal umbilical cord. Cells were cultured in serumfree neural stem cellconditioned medium or neural stem cellconditioned medium supplemented with Dkk1, a Wnt/13 catenin pathway antagonist, and LeftyA, a Nodal signaling pathway antagonist to induce differentiation into retinal progenitor cells. Inverted microscopy showed that after induction, the spindleshaped or fibroblastlike Wharton＇s jelly mesenchymal stem cells changed into bulbous cells with numerous processes. Immunofluorescent cytochemical stain ing and reversetranscription PCR showed positive expression of retinal progenitor cell markers, Pax6 and Rx, as well as weakly downregulated nestin expression. These results demonstrate that Wharton＇s jelly mesenchymal stem cells are capable of differentiating into retinal progenitor cells in vitro.
文摘The objective of the present study was to investigate the effects of genistein and equol on 3β-hydroxysteroid de- hydrogenase （3β-HSD） and 17β-hydroxysteroid dehydrogenase 3 （17β-HSD3） in human and rat testis microsomes. These enzymes （3β-HSD and 17β-HSD3）, along with two others （cytochrome P450 side-chain cleavage enzyme and cytochrome P450 17α-hydroxylase/17-20 lyase）, catalyze the reactions that convert the steroid cholesterol into the sex hormone testosterone. Genistein inhibited 3β-HSD activity （0.2 μmol L^-1 pregnenolone） with half-maximal inhibition or a half-maximal inhibitory concentration （IC50） of 87 ± 15 （human） and 636 ± 155 nmol L^-1 （rat）. Genistein＇s mode of action on 3β-HSD activity was competitive for the substrate pregnenolonrge and noncompetitive for the cofactor NAD＋. There was no difference in genistein＇s potency of 3β-HSD inhibition between intact rat Leydig cells and testis microsomes. In contrast to its potent inhibition of 3β-HSD, genistein had lesser effects on human and rat 17β-HSD3 （0.1 μmol L^-1 androstenedione）, with an IC50 〉 100μmol L^-1. On the other hand, equol only inhibited human 3β-HSD by 42%, and had no effect on 3β-HSD and 17β-HSD3 in rat tissues. These observations imply that the ability of soy isoflavones to regulate androgen biosynthesis in Leydig cells is due in part to action on Leydig cell 3β- HSD activity. Given the increasing intake of soy-based food products and their potential effect on blood androgen levels, these findings are greatly relevant to public health.
基金supported by the Natural Science Foundation of Heilongjiang Province of China,No.H2015083a grant from Higher Education Reform Project of Mudanjaing Medical University of China,No.2013016
文摘Animal and clinical studies have confirmed the therapeutic effect of bone marrow mesenchymal stem cells on cerebral ischemia, but their mechanisms of action remain poorly understood. Here, we summarize the transplantation approaches, directional migration, differentiation, replacement, neural circuit reconstruction,angiogenesis, neurotrophic factor secretion, apoptosis, immunomodulation, multiple mechanisms of action,and optimization strategies for bone marrow mesenchymal stem cells in the treatment of ischemic stroke.We also explore the safety of bone marrow mesenchymal stem cell transplantation and conclude that bone marrow mesenchymal stem cell transplantation is an important direction for future treatment of cerebral ischemia. Determining the optimal timing and dose for the transplantation are important directions for future research.
文摘The rapidly increasing prevalence of cognitive impairment and Alzheimer＇s disease has the potential to create a major worldwide healthcare crisis. Structural MRI studies in patients with Alzheimer＇s disease and mild cognitive impairment are currently attracting considerable interest. It is extremely important to study early structural and metabolic changes, such as those in the hippocampus, entorhinal cortex, and gray matter structures in the medial temporal lobe, to allow the early detection of mild cognitive impairment and AIzheimer＇s disease. The microstructural integrity of white matter can be studied with diffusion tensor imaging. Increased mean diffusivity and decreased fractional anisotropy are found in subjects with white matter damage. Functional imaging studies with positron emission tomography tracer compounds enable detection of amyloid plaques in the living brain in patients with Alzheimer＇s disease. In this review, we will focus on key findings from brain imaging studies in mild cognitive impairment and Alzheimer＇s disease, including structural brain changes studied with MRI and white matter changes seen with diffusion tensor imaging, and other specific imaging methodologies will also be discussed.
基金Supported by The Natural Science Foundation of China,Grants No.30801005,No.81273199and No.81270513the Project of Science and Development of Jilin Province(to Liu ZH)
文摘AIM: To investigate the expression and role of activin A in a mouse model of acute chemical liver injury. METHODS: Acute liver injury in C57BL/6 male mice was induced by intraperitoneal injection with carbon tetrachloride (CCl4 ) (0.5 mL/kg, body weight) dissolved in olive oil (1:19 v/v). Mice were sacrificed 1, 3, 5 and 7 d after the treatment. The levels of alanine aminotrans-ferase (ALT) and aspartate aminotransferase (AST) in serum were examined and pathological changes of liver observed by hematoxylin and eosin staining to evaluate the liver injury. Activin A protein levels in serum and hepatic tissue homogenate of mice were detected by enzyme-linked immunosorbent assay, and the expres-sion pattern of activin A protein in livers of mice was examined by immunohistochemistry. Activin type Ⅱ A receptor (ActRⅡA) and Smad3 expressions in the liver were analyzed by real-time quantitative reverse transcription-polymerase chain reaction. In order to further investigate the role of activin A, we also utilized activin A blocking experiment by anti-activin A antibody (500 μg/kg, body weight) injection into mouse tail vein. RESULTS: In CCl4-treated mice, serum ALT and AST levels were significantly increased, compared with that in control mice (P<0.01). Furthermore, the serious necrosis was observed around hepatic portal areas in CCl4-treated mice. Simultaneously, activin A levels in serum and hepatic tissue homogenate of mice treated with CCl4 for 1, 3 and 5 d increased significantly, com-pared with that in control mice (P<0.01). Activin A protein expression in hepatocytes not within the ne-crotic area was also upregulated in mice following CCl4 treatment. Not only activin A, but also ActRⅡA and activin signaling molecule Smad3 mRNA expressions in injury liver induced by CCl4 were significantly higher than that in control liver. In addition, levels of serum ALT and AST in CCl4-treated mice were significantly decreased by injection of anti-activin A antibody to block endogenous activin A action, compared with that in CCl4-treated mice by injection of immunoglobulin G instead of anti-activin A antibody (P<0.01), and the severity of liver injury was also reduced remarkably. CONCLUSION: These data show that activin A is in-volved in CCl4-induced acute liver injury. Blocking ac-tivin A actions may be a therapeutic approach for acute liver injury.
基金supported by the National Key Project of Scientific and Technical Supporting Programs fundedby Ministry of Science & Technology of China(No.2006BAD31B05)
文摘Chemical investigation of Syringa velutina Kom. led to the isolation of two new secoiridoid glucosides. Their structures were identified as 6＇-O-（6, 7-dihyrofoliamenthoyl）-8-epi-longisidic acid （syrveoside A, 1） and 6＇-O-menthiafoloyl-8-epi-ldngisidic acid （syrveoside B, 2） on the basis of chemical and physicochemical evidence.
文摘Selectins are carbohydrate-binding cell adhesion molecules that play a major role in the initiation of inflammatory responses. Accumulaed evidence has suggested that heparin＇s anti-inflammatory effects are mainly mediated by blocking L-or P-selectin-initiated cell adhesion. Recently, we have reported that periodate-oxidized, borohydridereduced heparin （RO-heparln） can inhibit P-selectin-mediated acute inflammation. Here we further examined the effect of RO-heparin on the adhesion of L-selectin-mediated leukocytes to vascular endothelium under flow conditions in vivo and in vitro. The results show that RO-heparin with a low anticoagulant activity can effectively reduce leucocyte roiling on thioglycoUate-induced rat mesenterlc venules and L-selectin-metadiated neutrophil roiling on TNF-α-induced human umbilical vein endothelial cells（HUVECs） under flow conditions. Our findings suggest that the effect of RO-heparin on inflammatory responses is mainly a result of its inhibiting the interaction between P- or L-selectin and its ligands. The findings also suggest that RO-heparin may be useful in preventing inflammation diseases.
文摘OBJECTIVE： The study was undertaken to explore a bibliometric approach to quantitatively assess the research on detection of monosialoganglioside from 2002 to 2011. DATA RETRIEVAL： A bibliometric analysis based on the publications on Web of Science was performed using key words such as ＂monosialoganglioside＂, ＂colloidal gold＂, ＂high performance liquid chromatography＂ and ＂detection＂. SELECTION CRITERIA： （1） Research articles on the detection of monosialoganglioside; （2） researches on human and animal fundamentals, clinical trials and case reports; （3） article types： article, review, proceedings paper, note, letter, editorial material, discussion, book chapter; （4） Publication year： 2002-2011. Exclusion criteria： （1） unrelated articles; （2） type of articles： correction; （3） articles from following databases： all databases related to social science and arts ＆ humanities in Web of Science were excluded. MAIN OUTCOME MEASURES： （1） distribution of subject areas; （2） number of publications annually; （3） document type and language of publications; （4） distribution of institutions; （5） distribution of output in journals; （6） the number of countries in which the article is published; （7） top cited paper. RESULTS： Overall population stands at 1 880 research articles addressing detection of monosialoganglioside in Web of Science during the study period. Articles （1 599） were the most frequently used document type comprising 85.05%, followed by meeting abstracts, reviews and proceedings papers. The distribution of subject categories showed that monosialoganglioside research covered both clinical and basic science research. The USA, Japan, and Italy were the three most productive countries, and the publication numbers in the USA were highest with 559 papers. The University of Milan, Nagoya University, and Kinki University are the most productive institutions regarding detection of monosialoganglioside. In 559 articles published by Americans, Medical College of Georgia ranked the first with 30 articles, followed by University of Medicine and Dentistry of New Jersey （28 articles）, Cornell University （24 articles） and Johns Hopkins University （24 articles）. In 442 articles published by Japanese, Nagoya University ranked the first with 40 articles, followed by Kinki University （36 articles）, and Dokkyo University （31 articles）. Though the total number of publications by Japanese is smaller than Americans, the top three institutions published more publications than American institutions. There is a markedly increase in the number of publications on the subject detection of monosialoganglioside in 2004, which the peak in the past 10 years. The valley bottom of the subject appeared in 2005. In total, the research is increased with time prolonged. Journal of Neurochemistry, Journal of Biological Chemistry and Journal of Neuroimmunology were core subject journals in monosialoganglioside studies. CONCLUSION： This study highlights the topics in detection of monosialoganglioside research that are being published around the world.
文摘The Al-doped Ni2P/AI-SBA-15 catalyst with high hydrodeoxygenation （HDO） activity was synthesized by tem- perature programmed reduction at a relatively low reduction temperature of 400 ℃. The as-prepared catalyst was characterized by X-ray diffraction （XRD）, H2 temperature-programmed reduction （H2-TPR）, X-ray photoelectron spectroscopy （XPS）, transmission electron microscope （TEM）, NH3 temperature programmed desorption （NH3-TPD）, N2 adsorption-desorption and CO uptake. The effect of AI on benzofuran （BF） HDO performance was investigated. The result indicates that the incorporation of AI into the SBA-15 support can promote the formation of much uniform, smaller, highly dispersed N2P particles on the catalyst. The AI also contrib- utes to suppress the enrichment of P and promote more exposed Ni sites on the surface. In addition, the incorporation of AI can enhance the acid strength. The total deoxygenated product yield over Ni2P/AI-SBA-15 reached 90.3%, which is an increase of 19.4%, when compared with that found for Ni2P/SBA-15 （70.9%）.
基金Supported by the National Natural Science Foundation of China(No.61175074,11272205)
文摘A moving-mass control method is introduced to stratospheric airship for its special working condition of low atmospheric density and low speed.The dynamic equation of airship is derived by using the Newton-Euler method and the mechanism of attitude control by moving masses is studied.Then the passive gliding of airship by the moving masses is given based on the theory of glider,and attitude control capability between moving mass and elevator is compared at different airspeed.Analysis results show that the motion of masses changes the gravity center of the airship system,which makes the inertia tensor and the gravity moment vary.Meanwhile,the aerodynamic angles are generated,which results in the change of aerodynamic moment.Control efficiency of moving masses is independent of airspeed.Thus the moving-mass control has the advantage over the aerodynamic surfaces at low airspeed.
基金supported by the National Natural Science Foundation of China,No.81870977 (to YW)the Natural Science Foundation of Heilongjiang of China,No.H2018068 (to WYL)+3 种基金the Basic Research Operating Expenses Program of Heilongjiang Provincial Universities of China,No.2019-KYYWFMY-0018 (to WYL)the Graduate Innovative Research Projects of Mudanjiang Medical College of China,No.YJSCX-MY22 (to DM)Key projects of Education Department of Hebei Province of China,No.ZD2020178 (to XMF)Hebei Key Laboratory of Nerve Injury and Repair of China (to XMF)。
文摘Our previous study has shown that the transcription factor Krüppel-like factor 7(KLF7) promotes peripheral nerve regeneration and motor function recovery after spinal cord injury.KLF7 also participates in traumatic brain injury,but its regulatory mechanisms remain poorly understood.In the present study,an HT22 cell model of traumatic brain injury was established by stretch injury and oxygenglucose deprivation.These cells were then transfected with an adeno-associated virus carrying KLF7(AAV-KLF7).The results revealed that,after stretch injury and oxygen-glucose deprivation,KLF7 greatly reduced apoptosis,activated caspase-3 and lactate dehydrogenase,downregulated the expression of the apoptotic markers B-cell lymphoma 2(Bcl-2)-associated X protein(Bax) and cleaved caspase-3,and increased the expression of βIII-tubulin and the antiapoptotic marker Bcl-2.Furthermore,KLF7 overexpression upregulated Janus kinase 2(JAK2) and signal transducer and activator of transcription 3(STAT3) phosphorylation in HT22 cells treated by stretch injury and oxygenglucose deprivation.Immunoprecipitation assays revealed that KLF7 directly participated in the phosphorylation of STAT3.In addition,treatment with AG490,a selective inhibitor of JAK2/STAT3,weakened the protective effects of KLF7.A mouse controlled cortical impact model of traumatic brain injury was then established.At 30 minutes before modeling,AAV-KLF7 was injected into the ipsilateral lateral ventricle.The protein and m RNA levels of KLF7 in the hippocampus were increased at 1 day after injury and recovered to normal levels at 3 days after injury.KLF7 reduced ipsilateral hippocampal atrophy,decreased the injured cortex volume,downregulated Bax and cleaved caspase-3 expression,and increased the number of 5-bromo-2'-deoxyuridine-positive neurons and Bcl-2 protein expression.Moreover,KLF7 transfection greatly enhanced the phosphorylation of JAK2 and STAT3 in the ipsilateral hippocampus.These results suggest that KLF7 may protect hippocampal neurons after traumatic brain injury through activation of the JAK2/STAT3 signaling pathway.The study was approved by the Institutional Review Board of Mudanjiang Medical University,China(approval No.mdjyxy-2018-0012) on March 6,2018.
