The CRISPR/dCas9 system is a gene editing tool that has proven to be highly efficient and precise. By utilizing transcriptional activators, such as VP64, p65, and Rta, the system can effectively and stably activate target genes. Sox17, a transcription factor belonging to the SOX family, plays a crucial role in the differentiation of the germ layers and the determination of cell fates during the early stages of embryonic development. Sheep embryonic stem cells (sESCs) are characterized by their capacity for self-renewal and multidirectional differentiation, serving as a significant in vitro model for studying the mechanisms of cell differentiation during early embryonic development. However, the importing of exogenous genes into sESCs is challenging due to their unique growth characteristics. The objective of this study was to investigate the conditions necessary for successfully activating Sox17 in sESCs. To this end, we employed the CRISPR/dCas9 system along with liposome transfection, lentivirus invasion, and electroporation to activate Sox17 in sESCs. The expression of Sox17 was then determined by fluorescence quantitative PCR, on the basis of which the performance of different transfection methods was compared. The results indicated that the electroporation group had the best transfection effect and the highest Sox17 expression among the three transfection methods. The efficient and stable gene activation protocol will provide a reference for embryonic stem cell research in other species, especially livestock animals, and lay the foundation for the subsequent study of gene function and realization of precise cell fate regulation by regulating gene expression in sheep embryonic stem cells.
Animals ; CRISPR-Cas Systems/genetics* ; Sheep ; SOXF Transcription Factors/genetics* ; Embryonic Stem Cells/cytology* ; Genetic Vectors/genetics* ; Cell Differentiation/genetics* ; Transfection ; Gene Editing/methods*

Objective:To provide guidance on parameters for future endovaginal coil magnetic resonance imaging(MRI)in vivo,and to investigate the imaging potential of the endovaginal coil technique.Methods:The endovaginal coil was used to perform T2-weighted turbo spin echo sequence imaging on a phantom containing three spatial resolution modules,with variations in key imaging parameters.Signal-to-noise ratio(SNR),contrast-to-noise ratio(CNR),and contrast(C)were calculated for images under different imaging parameters,and image quality was assessed based on scores within specified intervals.Structural display scores were determined for the three resolution modules of the phantom,and the non-parametric tests were used for statistical comparison between groups.Results:Under the main imaging parameters of a slice thickness of 2 mm,a slice gap of 0.2 mm,4 times of excitation repetition,a matrix size of 384×384,an FOV of 52 mm×52 mm,a TE of 74 ms,a bandwidth of 180 Hz/Pixel,and an acceleration factor of 18,good image quality was obtained with an acquired spatial resolution of 0.14 mm×0.14 mm×2.00 mm and a reconstructed resolution of 0.07 mm×0.07 mm×2.00 mm,and all three resolution modules were clearly visualized with a clinically acceptable imaging time.There were signifi-cant differences between groups in the imaging quality scores of slice thickness,slice gap,number of excitations,FOV,and accelera-tion factor(P<0.05),while there were no significant differences in matrix,TE,and bandwidth between groups(P=0.521,0.502,and 0.566).There were significant differences in the structural display scores for all parameters between groups(P<0.05).Conclusion:The parameters obtained in this experiment can guide the future ap-plication of endovaginal coils in the human body,demonstrating the extremely high imaging potential of this technique,and endovaginal coil has the potential of identifying small lesions in future clinical practice.

Objective:To investigate the nutritional risk status of children in PICU and analyze its influencing factors.Methods:From July 2021 to February 2023,all children aged 1 to 18 years admitted to PICU of Beijing Children's Hospital were investigated by using the pediatric Yorkhill Malnutrition Scoring tool(PYMS)and the clinical data questionnaire.Results:A total of 492 children in PICU were enrolled.The first nutritional risk screening results showed that there were 32 cases of no/low nutritional risk(6.5%),76 cases of medium risk(15.4%),and 384 cases of high risk(78.1%).The incidence of medium/high nutritional risk was as high as 93.5%.The PYMS score of nutritional risk in PICU was(2.61±1.42).The results of multiple linear regression analysis showed that weight,fever time before admission,white blood cells,body mass index,primary diagnosis,father's education,and diet before illness were the main influencing factors of nutritional risk of children in PICU(P<0.05).Conclusion:Children in PICU are in a state of high nutritional risk.It is suggested that children in PICU should carry out nutritional screening in a standardized manner,identify children with high nutritional risk and its influencing factors early.To actively conduct nutritional assessment and nutritional intervention could improve the clinical outcome of children in PICU.

Objective To observe the difference of bone micro-structure in different regions of proximal femur,micro-CT scanning was performed on 30 proximal femur specimens to explain the mechanism of proximal femur fracture and to provide anatomical basis for prosthesis design.Methods Totally 30 intact proximal femur specimens were obtained from 60-80 year-old cadavers.Micro-CT scanning was used to measure the trabecular thickness(Tb.Th),trabecular number(Tb.N),trabecular space(Tb.Sp),connectivity(Conn)and bone mineral density(BMD)and other parameters in 7 regions of proximal femur,including proximal pressure trabecular(PPT),distal pressure trabecular(DPT),femoral head-neck junction(FHNJ),head and neck of femoral neck(HNFN),the base of femoral neck(BPFN),intertrochanteric line(IL)and greater trochanter(GT).Results The bone mineral density of IL and GT were higher than those of BPFN,FHNJ,DPT and PPT.The trabecular thickness of GT was the largest,followed by IL,BPFN and HNFN,and the smallest was FHNJ,DPT and PPT.The trabecular space of IL was larger than that of GT,and the data of both were larger than those of other parts,among which DPT and PPT were the smallest.The trabecular number of IL and GT were the smallest,BPFN,HNFN and FHNJ were larger,and DPT was the largest.The volume fraction of IL was the smallest,BPFN and HNFN were larger,DPT and PPT were the largest.Conclusion The bone density,trabecular thickness,bone volume,and total volume of GT and IL in the proximal femur of elderly patients are all relatively large,so the reason for the high incidence of fractures is not due to weak internal bone microstructure;The bone density,trabecular thickness,and trabecular gap at the proximal and distal ends of the vertical trabecular bone are relatively small.If it is necessary to perform core decompression for prosthesis filling at this location,the design should be conducive to the mechanical conduction of the prosthesis and the regeneration of surrounding bone tissue.

Objective To explore the mechanism by which the sanguis draconis flavones(SDF)regulates the reactive oxygen species(ROS)/thioredoxin-interacting protein(TXNIP)pathway to mediate cell pyroptosis and improve cerebral ischemia-reperfusion injury(CIRI)in rats.Methods The experimental rats were randomly divided into the control group(Ctrl),the CIRI group,the low-dose SDF group(SDF-L),the high-dose SDF group(SDF-H),and the SDF-H+ROS/TXNIP pathway activator,trimethylamine oxide(TMAO)group(SDF-H+TMAO).Among them,except for the control group,the remaining rats all needed to establish the CIRI rat model by the modified suture method.Zea Longa scoring was performed on rats from each group.ELISA was used to detect the levels of serum inflammatory factors interleukin(IL)-1β,IL-18 and oxidative stress-related factors superoxide dismutase(SOD),malondialdehyde(MDA),glutathione peroxidase(GSH-Px).Flow cytometry was used to measure the ROS levels.Cerebral edema was detected.Cerebral infarction was detected by 2,3,5-triphenyl tetrazolium chloride(TTC)staining.HE staining was used to detect the pathological changes of brain tissue.Immunohistochemistry was used to detect the expression of pyrolytic effector protein dermolin D(GSDMD).Western blotting was used to detect the expression of proteins related to the ROS/TXNIP pathway.Results Compared with the control group,a large area of cerebral infarctions were observed in the brain tissue of the CIRI group,accompanied by mild hemorrhage and obvious infiltration of inflammatory cells.Neuronal cells underwent degeneration and necrosis,with sparse and disordered arrangement.The phenomena of nuclear condensation and nucleolus lysis were obvious.The Zea Longa score,cerebral infarction volume,brain tissue water content,levels of IL-1β,IL-18,ROS,MDA,and the expressions of GSDMD,TXNIP,nucleotide-binding oligomerization domain-like receptor protein 3(NLRP3),apoptosis-related punctate protein(ASC),and Caspase-1 increased,while the activities of SOD and GSH-Px decreased(P＜0.05).Compared with the CIRI group,the pathological damage of brain tissues in the SDF-L group and the SDF-H group was significantly improved.The Zea Longa score,cerebral infarction volume,brain tissue water content,levels of IL-1β,IL-18,ROS,MDA,and the expressions of GSDMD,TXNIP,NLRP3,ASC,and Caspase-1 decreased.The activities of SOD and GSH-Px increased(P＜0.05);TMAO treatment partially reversed the improvement effect of SDF on CIRI in rats.Conclusion SDF ameliorates cerebral CIRI in rats by inhibiting ROS/TXNIP pathway-mediated pyroptosis.

Objective To explore the effects of pretreatment with rehmannia glutinosa polysaccharide(RGP)and basic fibroblast growth factor(FGF-2)alone or in combination on the differentiation of bone marrow mesenchymal stem cells(BMSCs)into cardiomyoid cells and the related mechanisms.Methods BMSCs pretreated with FGF-2 and RGP alone or in combination were cultured for 1,2,and 4 weeks.The expression levels of NKx2.5 and GATA-4 were detected by Real-time PCR.BMSCs pretreated with FGF-2 or RGP alone and PI3K/Akt signaling pathway inhibitor LY294002 were used to detect the expression levels of myocardial specific proteins and related pathway proteins by Western blotting.Results Compared with the blank control group,pretreatment with FGF-2 or RGP alone increased the expression rate of myocardial specific markers,and the effect of combined pretreatment with FGF-2 and RGP was more obvious(P＜0.05).Compared with pretreatment with FGF-2 or RGP alone,pretreatment with LY294002 combined with FGF-2 or RGP significantly down-regulated the expression of cardiac-specific proteins in BMSCs and inhibited the phosphorylation of Akt(P＜0.05).Conclusion Both FGF-2 and RGP can induce BMSCs to differentiate into cardiomyocyte-like cells by regulating PI3K/Akt signaling pathway,and the combination of FGF-2 and RGP has a better inductive effect.

Objective To develop and validate a deep learning model for automatic identification of liver CT contrast-enhanced phases.Methods A total of 766 patients with liver CT contrast-enhanced images were retrospectively collected.A three-phase classification model and an arterial phase(AP)classification model were developed,so as to automatically identify liver CT contrast-enhanced phases as early arterial phase(EAP)or late arterial phase(LAP),portal venous phase(PVP),and equilibrium phase(EP).In addition,221 patients with liver CT contrast-enhanced images in 5 different hospitals were used for external validation.The annotation results of radiologists were used as a reference standard to evaluate the model performances.Results In the external validation datasets,the accuracy in identifying each enhanced phase reached to 90.50%-99.70%.Conclusion The automatic identification model of liver CT contrast-enhanced phases based on residual network may provide an efficient,objective,and unified image quality control tool.

Establishing a new paradigm for high-quality development in public hospitals,embracing a comprehensive,systematic,and innovative strategic management philosophy,and instituting a modern hospital management system hold significant practical importance.It investigates the pathways through which the Guangzhou Women and Children's Medical Center has fulfilled its strategic commitments over its 17-year history.It delves into the meaning and value of constructing hospital strategic commitments,explores pathways for realization,analyzes effects.It aims to understand the normative role of strategic commitments in shaping the development paths of specialized women's and children's hospitals and to provide a reference for the high-quality development of similar hospitals across China.

Establishing a new paradigm for high-quality development in public hospitals,embracing a comprehensive,systematic,and innovative strategic management philosophy,and instituting a modern hospital management system hold significant practical importance.It investigates the pathways through which the Guangzhou Women and Children's Medical Center has fulfilled its strategic commitments over its 17-year history.It delves into the meaning and value of constructing hospital strategic commitments,explores pathways for realization,analyzes effects.It aims to understand the normative role of strategic commitments in shaping the development paths of specialized women's and children's hospitals and to provide a reference for the high-quality development of similar hospitals across China.

Establishing a new paradigm for high-quality development in public hospitals,embracing a comprehensive,systematic,and innovative strategic management philosophy,and instituting a modern hospital management system hold significant practical importance.It investigates the pathways through which the Guangzhou Women and Children's Medical Center has fulfilled its strategic commitments over its 17-year history.It delves into the meaning and value of constructing hospital strategic commitments,explores pathways for realization,analyzes effects.It aims to understand the normative role of strategic commitments in shaping the development paths of specialized women's and children's hospitals and to provide a reference for the high-quality development of similar hospitals across China.