In recent years, with the development of single-cell sequencing technology, spatial transcriptome technology and in vivo tracing technology, scientists have a deeper understanding of scientific issues about the in vivo development, functional regulation and ex vivo expansion of hematopoietic stem cells (HSCs). Among them, epigenetic modification plays an important role in the development and fate decisions, function maintenance and ex vivo expansion of HSCs, which has become a research hotspot in the field of stem cells in recent years. This article reviews the recent research progress of epigenetic modification in the development, functional regulation and expansion of HSCs.
Hematopoietic Stem Cells ; Epigenesis, Genetic ; Humans ; DNA Methylation

The molecular mechanism of verbascoside(OC1) in promoting acetylcholine(ACh) release in the pathogenesis of Alzheimer's disease(AD) was studied. Adrenal pheochromocytoma cells(PC12) of rats induced by β-amyloid protein(1-42)(Aβ_(1-42)) were used as AD models in vitro and were divided into control group, model group(Aβ_(1-42) 10 μmol·L~(-1)), OC1 treatment group(2 and 10 μg·mL~(-1)). The effect of OC1 on phosphorylated proteins in AD models was analyzed by whole protein phosphorylation quantitative omics, and the selectivity of OC1 for calcium channel subtypes was virtually screened in combination with computer-aided drug design. The fluorescence probe Fluo-3/AM was used to detect Ca~(2+) concentration in cells. Western blot analysis was performed to detect the effects of OC1 on the expression of phosphorylated calmodulin-dependent protein kinase Ⅱ(p-CaMKⅡ, Thr286) and synaptic vesicle-related proteins, and UPLC/Q Exactive MS was used to detect the effects of OC1 on ACh release in AD models. The effects of OC1 on acetylcholine esterase(AChE) activity in AD models were detected. The results showed that the differentially modified proteins in the model group and the OC1 treatment group were related to calcium channel activation at three levels: GO classification, KEGG pathway, and protein domain. The results of molecular docking revealed the dominant role of L-type calcium channels. Fluo-3/AM fluorescence intensity decreased under the presence of Ca~(2+) chelating agent ethylene glycol tetraacetic acid(EGTA), L-type calcium channel blocker verapamil, and N-type calcium channel blocker conotoxin, and the effect of verapamil was stronger than that of conotoxin. This confirmed that OC1 promoted extracellular Ca~(2+) influx mainly through its interaction with L-type calcium channel protein. In addition, proteomic analysis and Western blot results showed that the expression of p-CaMKⅡ and downstream vesicle-related proteins was up-regulated after OC1 treatment, indicating that OC1 acted on vesicle-related proteins by activating CaMKⅡ and participated in synaptic remodeling and transmitter release, thus affecting learning and memory. OC1 also decreased the activity of AChE and prolonged the action time of ACh in synaptic gaps.
Animals ; Rats ; Glucosides/administration & dosage* ; Acetylcholine/metabolism* ; Alzheimer Disease/genetics* ; PC12 Cells ; Phenols/chemistry* ; Neurotransmitter Agents/metabolism* ; Drugs, Chinese Herbal ; Calcium-Calmodulin-Dependent Protein Kinase Type 2/genetics* ; Humans ; Phosphorylation/drug effects* ; Calcium/metabolism* ; Polyphenols

Objective To assess the effectiveness of the evaluation of military physical function(EMPF)system in predicting the occurrence of military training injuries among new recruits to provide scientific guidance and methodological choice for military training.Methods A total of 527 new recruits from 5 grassroots units from July 2016 to February 2018 were selected for the study.The recruits underwent EMPF testing,and their military training injuries were monitored over a 2-year follow-up period.Those who sustained injuries during training were divided into injury group(n=163),while the remaining recruits were placed in healthy group(n=364).The predictive ability of the total EMPF score for training injuries was assessed using the receiver operating characteristic curve(ROC),and the correlation between the total EMPF score,individual test scores,and military training injuries were analyzed using binary logistic regression.Results The total EMPF score of new recruits in injury group(19.52±1.97)was significantly lower than that of healthy group(24.31±1.54)(P<0.001),which also demonstrated a high diagnostic value in predicting the risk of military training injuries,with an area under the curve(AUC)of ROC of 0.971(P<0.001).A cut-off value of 22 scores was found to have the highest accuracy in predicting future training injuries,with an odds ratio(OR)of 25.63,sensitivity of 0.939,specificity of 0.879,positive likelihood ratio of 7.76,and a post-test probability of 0.67.Binary logistic regression analysis revealed that 6 EMPF tests,including holding the ball over and leaning back,bending forward and touching the ground with the ball,lunge squat and twist,swallow balance with holding the ball afterward,vertical jump,and respiratory pattern assessment,were negatively associated with the risk of military training injuries(P<0.0001).Conclusion The EMPF system can effectively predict the risk of military training injuries,with military personnel whose total EMPF score is less than 22 being at higher risk of sustaining such injuries.

High myopia is a refractive abnormality characterized by excessive elongation of the eye axis.The sclera,as an important part of the eye axis regulation,plays a key role in the occurrence and development of high myopia.In this pa-per,based on the domestic and international articles,the pathological changes and related regulatory molecules of the scle-ra in high myopia were systematically summarized from the features of scleral lesions in high myopia and the gene regula-tion and signaling pathways affecting the ultrastructure and mechanical properties of the sclera,thus providing a theoretical basis for the study of the pathological mechanism of high myopia.

High myopia is a refractive abnormality characterized by excessive elongation of the eye axis.The sclera,as an important part of the eye axis regulation,plays a key role in the occurrence and development of high myopia.In this pa-per,based on the domestic and international articles,the pathological changes and related regulatory molecules of the scle-ra in high myopia were systematically summarized from the features of scleral lesions in high myopia and the gene regula-tion and signaling pathways affecting the ultrastructure and mechanical properties of the sclera,thus providing a theoretical basis for the study of the pathological mechanism of high myopia.

Objective To establish the method for content determination of three lignans of Dendrobium Fimbriatum Hook..Methods The lignans in Dendrobium tasselii were identified by high-performance liquid chromatography/multi-stage mass spectrometry(HPLC-ESI/MSn)coupled with ultraviolet absorption spectrometry(UV)coupled with retention time localization of high-performance liquid chromatography(HPLC).The separation was carried out on a Kromasil 100-5 C18 column(4.6 mm×250 mm,5 μm)using a gradient elution of acetonitrile-0.1%formic acid solution as the mobile phase,the volume flow rate was 0.8 mL·min-1 and the column temperature was 35℃,and the mass spectrometry was performed using an ESI ion source with the data collected in the negative ion mode.The HPLC content was determined on the same column as that of MS analysis,with the mobile phase methanol + acetonitrile(V/V=1∶1)-0.01 mol/L ammonium acetate solution,gradient elution,flow rate of 0.8 mL·min-1,column temperature of 40℃,and detection wavelength of 215 nm.Results Syringaresinol di-O-glucoside and(-)-Syringaresinol 4-O-β-D-glucopyranoside and DL-Syringaresinol were identified from Dendrobium fimbriatum Hook.,and the results of content determination showed that the linear ranges of above three components were respectively 0.1701-3.4020,0.1020-2.0400,0.0403-0.8060 μg(r≥0.9995),the average recoveries were in the range of 97.71%-101.67%,and the relative standard deviations(RSDs)were all less than 3.0%.The contents of Syringaresinol di-O-glucoside and(-)-Syringaresinol 4-O-β-D-glucopyranoside and DL-Syringaresinol in the 10 batches of samples were 0.7779-1.3852,0.0734-0.1966,0.0295-0.1882 mg·g-1.Conclusion This research method can provide a reference basis for the quality evaluation method of Dendrobium fimbriatum Hook..

Tuberous sclerosis complex(TSC)is a rare genetic disease that can lead to benign dysplasia in multiple organs such as the skin, brain, eyes, oral cavity, heart, lungs, kidneys, liver, and bones. Its main symptoms include epilepsy, intellectual disabilities, skin depigmentation, and facial angiofibromas, whilst incidence is approximately 1 in 10 000 to 1 in 6000 newborns. This case presents a middle-aged woman who initially manifested with epilepsy and nodular depigmentation. Later, she developed a lower abdominal mass, elevated creatinine, and severe anemia. Based on clinical features and whole exome sequencing, the primary diagnosis was confirmed as TSC. Laboratory and imaging examinations revealed that the lower abdominal mass originated from the uterus. CT-guided biopsy pathology and surgical pathology suggested a combination of leiomyoma and abscess. With the involvement of multiple organs and various complications beyond the main diagnosis, the diagnostic and therapeutic process for this patient highlights the importance of rigorous clinical thinking and multidisciplinary collaboration in the diagnosis and treatment of rare and challenging diseases.

Diabetic kidney disease(DKD)is a high incidence microvascular complication caused by diabetes mellitus(DM).Persistent high glucose induces oxidative stress in the body.nuclear factor erythroid 2-related factor 2/heme oxygenase-1(Nrf2/HO-1)can play an anti-inflammatory and anti-oxidative role by inhibiting the accumulation of extracellular matrix in glomerular mesangium,inhibiting epithelial-mesenchymal transition in renal tubular epithelial cells,and inhibiting iron apoptosis,so as to improve renal function damage and delay the process of DKD.This article reviews the relationship between Nrf2/HO-1 pathway and DKD and the effect of traditional Chinese medicine active ingredients on DKD through Nrf2/HO-1 signaling pathway,in order to provide a basis for the development of new drugs.

Objective To provide references for reasonable equipping of airborne medical equipment oriented to different tasks by constructing a medical equipment requirement model for the helicopter evacuation and rescue team.Methods Relevant basic data were collected and organized on time for routine and emergency medical treatment and elementary medical equipment requirements for types of medical treatment.AnyLogic multi-agent modeling was used to established a medical equipment requirement model for the helicopter evacuation and rescue team,with the casualty,equipment and medical personnel as the agent modules and the logical relationship-based access rules between the agents.An example was taken with a Z-8 helicopter transformed into an ambulance platform to transport the rescue team and casualties,in which a variety of evacuation tasks with multi combinations of light and serious casualties were simulated and the model developed was used to record and analyze the data on waiting time for medical treatment,completion rate,personnel utilization rate and equipment requirement during 100 times of simulation flight.Results The model developed could provide generalized medical equipment allocation programs for the helicopter evacuation and rescue team to complete a variety of evacuation tasks in terms of electronic device,treatment equipment,auxiliary instrument and medical consumables.Conclusion The model developed facilitates rational allocation of medical equipment for the helicopter evacuation and rescue team.[Chinese Medical Equipment Journal,2024,45(5):28-33]