Objective To optimize the platelet enrichment method,and to analyze the concentration changes of key molecules in platelet-rich plasma(PRP)before and after activation,as well as the impact of its activated products on the proliferation of rat endothelial progenitor cells.Methods The tube double-centrifu-gation method was employed to optimize platelet enrichment,and the platelet count in the enriched PRP was measured.ELISA was used to detect the concentration changes of vascular endothelial growth factor(VEGF),endostatin(ES),and P-selectin(CD62P)in PRP before and after activation.The PRP was activated by using liquid nitrogen freeze-thaw method,and the effect of its activated products on the proliferation of rat endothelial progenitor cells was evaluated by using the methyl thiazolyl tetrazolium(MTT)assay.Results The optimal enrichment coefficient of platelets achieved by the double-centrifugation method was 4.63.After low-speed,long-duration double centrifugation,the platelet count was highest in the upper layer of the buffy coat.For PRP with a platelet count of 500× 109/L obtained by machine collection,the VEGF con-centrations before and after activation were(3 418.12±488.80)pg/mL and(4 530.04±308.30)pg/mL,re-spectively,the ES concentrations were(6 168.98±253.22)pg/mL and(6 594.65±82.47)pg/mL,respec-tively,the CD62P concentrations were(6 678.23±324.15)pg/mL and(17 630.53±746.24)pg/mL,respec-tively,statistically significant differences were observed in the above indicators before and after activation(P＜0.01).The activated PRP was diluted in a gradient manner by using a specialized culture medium for en-dothelial progenitor cells.MTT assay results indicated that,in the basal medium,the optimal volume fraction for promoting endothelial progenitor cell proliferation was 0.25％after 48 hours of culture;in the complete medium,the optimal volume fractions for promoting endothelial progenitor cell proliferation were 0.062 5％after 24 hours and 0.125％after 48 hours.Conclusion The concentrations of VEGF,ES,and CD62P in the optimized,enriched PRP exhibited significant changes before and after activation.The optimal volume fraction for promoting endothelial progenitor cell proliferation in the basal medium was 0.25％.

AIM:This study aims to investigate the impact of TWIK-1 channels on abnormal pacemaker activi-ties induced by hypokalemia and to elucidate the underlying mechanisms.METHODS:The gene sequences encoding hu-man TWIK-1,specific TWIK-1 shRNA and TWIK-1-T118i mutant were synthesized and subsequently subcloned into lenti-viral vectors.To knock down the TWIK-1 gene in human induced pluripotent stem cell-derived cardiomyocytes(hiPSC-CMs),the cells were transduced with lentivirus carrying the specific TWIK-1 shRNA sequences.For the overexpression of TWIK-1 or the TWIK-1-T118i mutant in HL-1 mouse cardiomyocytes,the cells received lentiviral transduction containing the respective gene sequences.Patch-clamp techniques were employed to assess the effects of 1 mmol/L extracellular K+on the membrane potentials and whole-cell currents of the cardiomyocytes.RESULTS:Under conditions of 1 mmol/L extra-cellular K+,depolarization of membrane potentials was observed in the hiPSC-CMs and the HL-1 mouse cardiomyocytes ex-pressing human TWIK-1 channel,leading to the induction of abnormal pacemaker activities.This phenomenon could be reversibly abolished by the removal of extracellular Na+or inhibited through TWIK-1 knockdown.In contrast,the mem-brane potentials of HL-1 mouse cardiomyocytes expressing human TWIK-1-T118i mutant hyperpolarized,with no occur-rence of abnormal pacemaker activities.The hiPSC-CMs exhibiting abnormal pacemaker activities at 1 mmol/L extracellu-lar K+demonstrated TWIK-1-like Na+leak currents,which were blocked by quinine,a non-selective blocker of TWIK-1.CONCLUSION:The TWIK-1 channels play a critical role in the development of hypokalemia-induced abnormal pace-maker activities in human cardiomyocytes by facilitating Na+leak currents.

AIM:To investigate the impact of Kir2.1 channels on abnormal spontaneous pacemaker activities induced by hypokalemia and to elucidate the underlying mechanisms.METHODS:Human induced pluripotent stem cell-derived cardiomyocytes(hiPSC-CMs)were transfected with lentiviral particles containing sequences for human Kir2.1,the Kir2.1-E224G mutant,or Kir4.1.Patch clamp techniques were employed to examine the effects of low extracellular potassium concentration([K+]e)of 1 mmol/L on the resting membrane potentials and whole-cell currents of the cells in each group,assessed via both current and voltage clamp modes.RESULTS:Under conditions of 1 mmol/L[K+]e,cur-rent clamp data revealed that hiPSC-CMs overexpressing Kir2.1 channels exhibited both hyperpolarized and depolarized resting membrane potentials,with the depolarized state triggering abnormal pacemaker activities.In contrast,cells overex-pressing the Kir2.1-E224G mutant or Kir4.1 channels displayed only hyperpolarized resting membrane potentials.Voltage clamp analysis indicated that hiPSC-CMs overexpressing Kir2.1 channels produced"N"-shaped whole-cell currents,whereas cells expressing the Kir2.1-E224G mutant or Kir4.1 exhibited typical K+currents.CONCLUSION:Kir2.1 channels play a crucial role in mediating hypokalemia-induced abnormal spontaneous pacemaker activities in human car-diomyocytes through their inward rectification properties.

AIM:This study aims to investigate the impact of TWIK-1 channels on abnormal pacemaker activi-ties induced by hypokalemia and to elucidate the underlying mechanisms.METHODS:The gene sequences encoding hu-man TWIK-1,specific TWIK-1 shRNA and TWIK-1-T118i mutant were synthesized and subsequently subcloned into lenti-viral vectors.To knock down the TWIK-1 gene in human induced pluripotent stem cell-derived cardiomyocytes(hiPSC-CMs),the cells were transduced with lentivirus carrying the specific TWIK-1 shRNA sequences.For the overexpression of TWIK-1 or the TWIK-1-T118i mutant in HL-1 mouse cardiomyocytes,the cells received lentiviral transduction containing the respective gene sequences.Patch-clamp techniques were employed to assess the effects of 1 mmol/L extracellular K+on the membrane potentials and whole-cell currents of the cardiomyocytes.RESULTS:Under conditions of 1 mmol/L extra-cellular K+,depolarization of membrane potentials was observed in the hiPSC-CMs and the HL-1 mouse cardiomyocytes ex-pressing human TWIK-1 channel,leading to the induction of abnormal pacemaker activities.This phenomenon could be reversibly abolished by the removal of extracellular Na+or inhibited through TWIK-1 knockdown.In contrast,the mem-brane potentials of HL-1 mouse cardiomyocytes expressing human TWIK-1-T118i mutant hyperpolarized,with no occur-rence of abnormal pacemaker activities.The hiPSC-CMs exhibiting abnormal pacemaker activities at 1 mmol/L extracellu-lar K+demonstrated TWIK-1-like Na+leak currents,which were blocked by quinine,a non-selective blocker of TWIK-1.CONCLUSION:The TWIK-1 channels play a critical role in the development of hypokalemia-induced abnormal pace-maker activities in human cardiomyocytes by facilitating Na+leak currents.

AIM:To investigate the impact of Kir2.1 channels on abnormal spontaneous pacemaker activities induced by hypokalemia and to elucidate the underlying mechanisms.METHODS:Human induced pluripotent stem cell-derived cardiomyocytes(hiPSC-CMs)were transfected with lentiviral particles containing sequences for human Kir2.1,the Kir2.1-E224G mutant,or Kir4.1.Patch clamp techniques were employed to examine the effects of low extracellular potassium concentration([K+]e)of 1 mmol/L on the resting membrane potentials and whole-cell currents of the cells in each group,assessed via both current and voltage clamp modes.RESULTS:Under conditions of 1 mmol/L[K+]e,cur-rent clamp data revealed that hiPSC-CMs overexpressing Kir2.1 channels exhibited both hyperpolarized and depolarized resting membrane potentials,with the depolarized state triggering abnormal pacemaker activities.In contrast,cells overex-pressing the Kir2.1-E224G mutant or Kir4.1 channels displayed only hyperpolarized resting membrane potentials.Voltage clamp analysis indicated that hiPSC-CMs overexpressing Kir2.1 channels produced"N"-shaped whole-cell currents,whereas cells expressing the Kir2.1-E224G mutant or Kir4.1 exhibited typical K+currents.CONCLUSION:Kir2.1 channels play a crucial role in mediating hypokalemia-induced abnormal spontaneous pacemaker activities in human car-diomyocytes through their inward rectification properties.

Objective:To investigate the expression and role of DEAD-box RNA helicases 5(DDX5 helicases)in head and neck squamous carcinoma(HNSCC).Methods:Tissue microarray microarray was used to assess relevant mRNA expression profile data,and R software was used to screen differential mRNAs(DEGs).The expression level of DDX5 was predicted using GEPIA 2,TCGA databases,and detected by immunohistochemistry,western blot and RT-qPCR in the HNSCC tissue and cell lines.Based on high-throughput sequencing data of DECs,differentially expressed miRNAs(DEMIs)relevant DDX5 competitive endogenous RNA network(ceRNA)was constructed.The software cytoscape was used to visualize the ceRNA network map and further screen the regulatory ax-is.Results:The results of microarray screening revealed that DDX5 expression in HNSCC was upregulated.Immunohistochemistry ver-ified that DDX5 was stronger expressed in the nuclei of squamous carcinoma cells.qPCR results suggested that significant expression of DDX5 mRNA at the tissue and cellular levels(P＜0.05).Western blot results showed high expression of DDX5 protein in the tissues.The ceRNA network was constructed,from which the relevant HNSCC axis circRNA-039626-miR-222-5p-DDX5 was identified.Con-clusion:DDX5 is highly expressed in HNSCC,and the circRNA-039626-miR-222-5p-DDX5 axis may be a potential regulatory axis for the development of HNSCC.

DDX5 helicase (DEAD box helicases 5), also known as P68, is an important member of an ATP dependent RNA helicase.Studies have shown that DDX5 is abnormally expressed in a variety of cancers, targeting a variety of tumor related signal pathways, regulating upstream and downstream factors to affect the occurrence, invasion and migration of tumor cells. This article describes the biological role of DDX5 in malignant tumors and provides prospects for targeted treatment of tumors.

OBJECTIVE: Dexmedetomidine (DEX), the most specific α ₂-adrenergic receptor agonist widely used for its sedative and analgesic properties, has been reported to upregulate HIF-1α expression to protect hypoxic and ischemic tissues. However, it is largely unclear whether DEX can also upregulate Hypoxia-inducible factor-1 alpha (HIF-1α) expression and its downstream vascular endothelial growth factor-A (VEGFA) in cancer tissues with oxygen-deficient tumor microenvironment. METHODS: We used SMMC-7721 cells, MHCC97-H cells, and a mouse model of orthotopic hepatic carcinoma to explore the effect of DEX on angiogenesis and vasculogenic mimicry (VM) and its mechanism. Under normoxic (20% O ₂) and hypoxic (1% O ₂) conditions, DEX was used to intervene cells, and yohimbine was used to rescue them. RESULTS: The results showed that DEX promoted angiogenesis and VM in human liver cancer cells within a certain dose range, and the addition of yohimbine inhibited this effect. DEX could activate HIF-1α/VEGFA pathway, which was further verified by silencing HIF-1α. Consistently, in vivo results also showed that DEX can up-regulate HIF-1α/VEGFA expression, and enhance the number of VM channels and microvessel density (MVD). CONCLUSION We believe that HIF-1α/VEGFA might be an important signaling pathway by which DEX promotes angiogenesis and VM formation in human hepatocellular carcinoma, whereas α ₂-adrenergic receptor mediation might be the critical mechanisms.
Animals ; Humans ; Mice ; Adrenergic alpha-2 Receptor Agonists/pharmacology* ; Carcinoma, Hepatocellular ; Cardiovascular Physiological Phenomena ; Dexmedetomidine/pharmacology* ; Hypoxia ; Liver Neoplasms/drug therapy* ; Oxygen ; Tumor Microenvironment ; Vascular Endothelial Growth Factor A/genetics* ; Receptors, Adrenergic, alpha-2/metabolism*

Model informed precision dosing for warfarin is to provide individualized dosing by integrating information related to patient characteristics, disease status and pharmacokinetics /pharmacodynamics of warfarin, through mathematical modeling and simulation techniques based on the quantitative pharmacology. Compared with empirical dosing, it can improve the safety, effectiveness, economy, and adherence of pharmacotherapy of warfarin. This consensus report describes the commonly used modeling and simulation techniques for warfarin, their application in developing and adjusting dosing regimens, medication adherence and economy. Moreover, this consensus also elaborates the detailed procedures for the implementation in the warfarin pharmacy service pathway to facilitate the development and application of model informed precision dosing for warfarin.

OBJECTIVEThis research aims to further explore the expression and significance of proliferating cell nuclear antigen (PCNA) and P53 in regenerating rat atrophy parotid gland from the gene and protein levels.

METHODSOne hundred and two Wistar rats were randomly divided into experimental and control groups; the former group's duct was ligated and then released respectively in 7 (Group A) and 14 days (Group B). Fresh parotid specimens were obtained at 0, 3, 5, 7, 10, 14, 21, and 28 days after being released. Hematoxylin-eosin staining method was used to observe the morphological changes of the parotid gland. The significance of P53 and PCNA in two groups was resolved by real-time fluorescence quantitative polymerase china reaction and Western blot.

RESULTSAcinar cells aoptosis and duct cells proliferation occurred when the occlusion of the parotid duct was reversed on days 7 and 14. The expression of P53 was higher than that of PCNA, and they reached the peak at the third and fifth days after groups A and B regenerated, respectively. This finding was significantly different compared with the control (P<0.01). P53 and PCNA contents decreased gradually; acinar and duct gradually returned to normal morphology; PCNA and P53 contents gradually close to the normal control group.

CONCLUSIONSAfter ligating the parotid duct, P53 was highly expressed, and induced parotid gland atrophy. Mean-while, PCNA was highly expressed, which then decreased inducing gland recovery.