Objective To investigate the prognostic value of perfusion MRI in elderly patients with posterior circulation cerebral ischemia after interventional therapy.Methods A prospective study was conducted on 200 patients with posterior circulation cerebral ischemia who received interven-tional therapy in our hospital from June 2021 to March 2024.According to the prognosis,they were divided into a good prognosis group(142 patients)and a poor prognosis group(58 patients).The detection rate of abnormal sequences and related parameters were compared between the two groups.ROC curve analysis was adopted to evaluate the diagnostic efficiency of cerebral blood vo-lume(CBV),time to peak(TTP),mean transmit time(MTT)and cerebral blood flow(CBF)alone and combined together.Results The poor prognosis group had significantly higher abnor-mal detection rates than the good prognosis group(all P＜0.05).Obvious differences were observed between the two groups in terms of lesion location,stenosis rate,and CBF values in bilateral occipital lobes and cerebelli(all P＜0.01).The good prognosis group exhibited higher CBV and CBF values and lower TTP and MTT values than the poor prognosis group(P＜0.01).The above four values combined together showed better diagnostic efficiency than any single va-lues and obtained biggest AUC value,and the cut-off value of CBV,TTP,MTT,and CBF was 751.23 ml,21.03 s,590.55 s,and 257.88 ml/(100 g·min),respectively.Conclusion The com-bined diagnosis of perfusion MRI indicators can significantly improve the prognostic efficiency after interventional therapy in elderly patients with posterior circulation cerebral ischemia.

BACKGROUND:Human umbilical cord mesenchymal stem cell-derived exosomes are involved in multiple injury repair processes,and the effects and the specific mechanisms of renal ischemia/reperfusion injury have not been fully elucidated.OBJECTIVE:To investigate the molecular mechanism of human umbilical cord mesenchymal stem cell-derived exosomes in the treatment of renal ischemia/reperfusion injury.METHODS:(1) Human umbilical cord mesenchymal stem cells were cultured and exosomes were obtained and identified using an exosome extraction kit.(2) The distribution of exosomes in the kidney of mice with renal ischemia/reperfusion injury was examined by intravital fluorescence imaging.(3) Thirty C57/BL6 male mice were divided into five groups according to the random number table method:sham operation group,renal ischemia/reperfusion group,sham operation group+Compound C group,renal ischemia/reperfusion+exosome group (exosome group),and renal ischemia/reperfusion+exosome+Compound C group (exosome+Compound C group),with 6 mice in each group.Except the sham operation group,bilateral renal pedicles were clamped for 45 minutes and a mouse model of renal ischemia/reperfusion injury was established after 24 hours of reperfusion.In sham operation+Compound C group and exosome+Compound C group,AMPK inhibitor Compound C was intraperitoneally injected 30 minutes before model establishment.In the exosome group and exosome+Copmpound C group,exosomes were injected through the tail vein 15 minutes before renal pedicle clipping.The levels of serum creatinine and urea nitrogen,interleukin 6,and tumor necrosis factor α in renal tissue,and the expression of apoptosis-related factors in renal tissue were detected after 24 hours of reperfusion in each group.RESULTS AND CONCLUSION:(1) Human umbilical cord mesenchymal stem cell exosomes had the typical tea tray morphology,with the diameter distribution in the range of 40-160 nm,and expressed the specific marker membrane protein of exosome surface.(2) Murine kidneys after renal ischemia/reperfusion injury were more likely to gather human umbilical cord mesenchymal stem cell exosomes compared with the sham operation group.(3) Exosome pretreatment reduced renal injury and the level of renal cell apoptosis in mice treated with renal ischemia/reperfusion injury.Moreover,this protective effect could be reversed by AMPK inhibitors.These findings verify that human umbilical cord mesenchymal stem cell-derived exosomes exerting a protective effect on renal ischemia/reperfusion injury may be related to the activation of the AMPK/YAP1 pathway to antiapoptosis.

BACKGROUND:Human umbilical cord mesenchymal stem cell-derived exosomes are involved in multiple injury repair processes,and the effects and the specific mechanisms of renal ischemia/reperfusion injury have not been fully elucidated.OBJECTIVE:To investigate the molecular mechanism of human umbilical cord mesenchymal stem cell-derived exosomes in the treatment of renal ischemia/reperfusion injury.METHODS:(1) Human umbilical cord mesenchymal stem cells were cultured and exosomes were obtained and identified using an exosome extraction kit.(2) The distribution of exosomes in the kidney of mice with renal ischemia/reperfusion injury was examined by intravital fluorescence imaging.(3) Thirty C57/BL6 male mice were divided into five groups according to the random number table method:sham operation group,renal ischemia/reperfusion group,sham operation group+Compound C group,renal ischemia/reperfusion+exosome group (exosome group),and renal ischemia/reperfusion+exosome+Compound C group (exosome+Compound C group),with 6 mice in each group.Except the sham operation group,bilateral renal pedicles were clamped for 45 minutes and a mouse model of renal ischemia/reperfusion injury was established after 24 hours of reperfusion.In sham operation+Compound C group and exosome+Compound C group,AMPK inhibitor Compound C was intraperitoneally injected 30 minutes before model establishment.In the exosome group and exosome+Copmpound C group,exosomes were injected through the tail vein 15 minutes before renal pedicle clipping.The levels of serum creatinine and urea nitrogen,interleukin 6,and tumor necrosis factor α in renal tissue,and the expression of apoptosis-related factors in renal tissue were detected after 24 hours of reperfusion in each group.RESULTS AND CONCLUSION:(1) Human umbilical cord mesenchymal stem cell exosomes had the typical tea tray morphology,with the diameter distribution in the range of 40-160 nm,and expressed the specific marker membrane protein of exosome surface.(2) Murine kidneys after renal ischemia/reperfusion injury were more likely to gather human umbilical cord mesenchymal stem cell exosomes compared with the sham operation group.(3) Exosome pretreatment reduced renal injury and the level of renal cell apoptosis in mice treated with renal ischemia/reperfusion injury.Moreover,this protective effect could be reversed by AMPK inhibitors.These findings verify that human umbilical cord mesenchymal stem cell-derived exosomes exerting a protective effect on renal ischemia/reperfusion injury may be related to the activation of the AMPK/YAP1 pathway to antiapoptosis.

Objective To investigate the prognostic value of perfusion MRI in elderly patients with posterior circulation cerebral ischemia after interventional therapy.Methods A prospective study was conducted on 200 patients with posterior circulation cerebral ischemia who received interven-tional therapy in our hospital from June 2021 to March 2024.According to the prognosis,they were divided into a good prognosis group(142 patients)and a poor prognosis group(58 patients).The detection rate of abnormal sequences and related parameters were compared between the two groups.ROC curve analysis was adopted to evaluate the diagnostic efficiency of cerebral blood vo-lume(CBV),time to peak(TTP),mean transmit time(MTT)and cerebral blood flow(CBF)alone and combined together.Results The poor prognosis group had significantly higher abnor-mal detection rates than the good prognosis group(all P＜0.05).Obvious differences were observed between the two groups in terms of lesion location,stenosis rate,and CBF values in bilateral occipital lobes and cerebelli(all P＜0.01).The good prognosis group exhibited higher CBV and CBF values and lower TTP and MTT values than the poor prognosis group(P＜0.01).The above four values combined together showed better diagnostic efficiency than any single va-lues and obtained biggest AUC value,and the cut-off value of CBV,TTP,MTT,and CBF was 751.23 ml,21.03 s,590.55 s,and 257.88 ml/(100 g·min),respectively.Conclusion The com-bined diagnosis of perfusion MRI indicators can significantly improve the prognostic efficiency after interventional therapy in elderly patients with posterior circulation cerebral ischemia.

Doxorubicin(DOX)is a commonly administered chemotherapy drug for treating hematological malignancies and solid tumors;however,its clinical application is limited by significant cardiotoxicity.Cynaroside(Cyn)is a flavonoid glycoside distributed in honeysuckle,with confirmed potential biological functions in regulating inflammation,pyroptosis,and oxidative stress.Herein,the effects of Cyn were evaluated in a DOX-induced cardiotoxicity(DIC)mouse model,which was established by intraperitoneal injections of DOX(5 mg/kg)once a week for three weeks.The mice in the treatment group received dexrazoxane,MCC950,and Cyn every two days.Blood biochemistry,histopathology,immunohistochemistry,reverse transcription-quantitative polymerase chain reaction(RT-qPCR),and western blotting were conducted to investigate the cardioprotective effects and potential mechanisms of Cyn treatment.The results demonstrated the significant benefits of Cyn treatment in mitigating DIC;it could effectively alleviate oxidative stress to a certain extent,maintain the equilibrium of cell apoptosis,and enhance the cardiac function of mice.These effects were realized via regulating the transcription levels of pyroptosis-related genes,such as nucleotide-binding oligomerization domain-like receptor protein 3(NLRP3),caspase-1,and gasdermin D(GSDMD).Mechanistically,for DOX-induced myocardial injury,Cyn could significantly modulate the expression of pivotal genes,including adenosine monophosphate-activated protein kinase(AMPK),peroxisome proliferator-activated receptor γ coactivator-1α(PGC-1α),sirtuin 3(SIRT3),and nuclear factor erythroid 2-related factor 2(Nrf2).We attribute it to the mediation of AMPK/SIRT3/Nrf2 pathway,which plays a central role in preventing DOX-induced cardiomyocyte injury.In conclusion,the present study confirms the therapeutic potential of Cyn in DIC by regulating the AMPK/SIRT3/Nrf2 pathway.

Objective:To evaluate the role of nuclear factor E2-related factor 2 (Nrf2)/heme oxidase-1 (HO-1) in reduction of renal ischemia-reperfusion (I/R) injury by the human umbilical cord mesenchymal stem cells (hucMSCs)-derived exosomes (hucMSCs-exo) in mice.Methods:The hucMSCs were cultured, and exosomes were extracted and identified by transmission electron microscopy, nanoparticle tracking analysis and Western blot. Thirty-six male SPF-grade C57BL/6 mice, weighing 20-25 g, were used. Thirty mice were selected and divided into 5 groups ( n=6 each) by a random number table method: sham operation group (Sham group), sham operation + Nrf2 inhibitor ML385 group (Sham + ML385 group), renal I/R group (I/R group), renal I/R + exosome group (I/R+ EXO group), and renal I/R + exosome + Nrf2 inhibitor ML385 group (I/R+ EXO+ ML385 group). A model of renal I/R injury was prepared by clamping the bilateral renal pedicles for 45 min followed by perfusion in anesthetized animals. ML385 30 mg/kg was intraperitoneally injected at 45 min before preparing the model in Sham+ ML385 group and I/R+ EXO+ ML385 group, and hucMSCs-exo 100 μg was injected via the tail vein at 15 min before reperfusion in I/R+ EXO group and I/R+ EXO+ ML385 group. Serum blood urea nitrogen (BUN) and creatinine (Cr) concentrations were detected at 24 h of reperfusion. The renal tissues were obtained for examination of the pathological changes and for determination of contents of interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α) and malondialdehyde (MDA), superoxide dismutase (SOD) activity and reactive oxygen species (ROS) levels and expression of Nrf2 and HO-1 protein and mRNA (by Western blot and quantitative real-time polymerase chain reaction). The left 6 mice were allocated to sham operation group (Sham-IM group, n=3) and renal I/R group (I/R-IM group, n=3) by a random number table method for VISQUE in living imaging observation. Results:The exosomes showed a typical cup-shaped morphology with a transmission electron microscope, the nanoparticles tracked and analyzed the average diameter of the exosome, with an average diameter of 96.7 nm, and the positive expression of surface markers CD9, CD63 and TSG101 was detected using Western blot. The renal fluorescence intensity value was significantly increased in I/R-IM group as compared with Sham-IM group ( P<0.05). Compared with Sham group, the serum BUN and Cr concentrations were significantly increased, the contents of IL-6, TNF-α and MDA and ROS levels were increased, the activity of SOD was decreased, the expression of Nrf2 and HO-1 protein and mRNA was down-regulated ( P<0.05), and the pathological changes of renal tissues were aggravated in I/R group, and no significant change was found in serum BUN and Cr concentrations in Sham+ ML385 group ( P>0.05). Compared with I/R group, the serum BUN and Cr concentrations were significantly decreased, the contents of IL-6, TNF-α and MDA and ROS levels were decreased, the activity of SOD was increased, the expression of Nrf2 and HO-1 protein and mRNA was up-regulated ( P<0.05), and the pathological changes of renal tissues were significantly attenuated in I/R+ EXO group. Compared with I/R+ EXO group, the serum BUN and Cr concentrations were significantly increased, the contents of IL-6, TNF-α and MDA and ROS levels were increased, the activity of SOD was decreased, the expression of Nrf2 and HO-1 protein and mRNA was down-regulated ( P<0.05), and the pathological changes of renal tissues were aggravated in I/R+ EXO+ ML385 group. Conclusions:The mechanism by which hucMSCs-exo reduces renal I/R injury may be related to activation of the Nrf2/HO-1 signaling pathway in mice.

Objective To investigate the protective effect of human umbilical cord mesenchymal stem cell-derived exosome (hucMSC-Exo) on renal ischemia-reperfusion injury (IRI), and to clarify the critical role and regulating mechanism of transient receptor potential canonical (TRPC) 6/poly adenosine-diphosphate-ribose polymerase (PARP) 1 signaling pathway during this process. Methods The hucMSC-Exo was extracted by ultracentrifugation, and identified by transmission electron microscope (TEM), nanoparticle tracing analysis and Western blot. SD rats were randomly divided into the sham operation group (group S), sham operation+TRPC6 inhibitor SKF96365 group (group SS), renal IRI group (group IRI), exosome treatment group (group EXO) and exosome +TRPC6 inhibitor SKF96365 group (group ES), with 6 rats in each group. Serum creatinine and blood urea nitrogen levels were detected. Pathological changes of renal tissues were observed by hematoxylin-eosin (HE) staining and Paller score was calculated. The expression levels of key molecules of necroptosis in rat renal tissues, including receptor-interacting protein kinase (RIPK)1, RIPK3 and mixed-lineage kinase domain-like protein (MLKL), TRPC6 and PARP1, were detected by Western blot. Results Typical saucer-like structure was observed under TEM. Nanoparticle tracing analysis showed that the average diameter of the extracted substance was 125.9 nm. Western blot revealed that the surface markers of CD9, CD63 and CD81 were positively expressed, confirmed that the extracted substance was exosome. Compared with group S, the serum creatinine and blood urea nitrogen levels were up-regulated, the pathological damage of renal tissues was worsened, Paller score was elevated, the relative expression levels of TRPC6 and PARP1 proteins were down-regulated, and the relative expression levels of RIPK1, RIPK3 and MLKL proteins were up-regulated in group IRI (all P < 0.05). Compared with group IRI, the serum creatinine and blood urea nitrogen levels were down-regulated, the pathological damage of renal tissues was mitigated, Paller score was decreased, the relative expression levels of TRPC6 and PARP1 proteins were up-regulated, and the relative expression levels of RIPK1, RIPK3 and MLKL proteins were down-regulated in group EXO (all P < 0.05). Compared with group EXO, the serum creatinine and blood urea nitrogen levels were up-regulated, the pathological damage of renal tissues was aggravated, Paller score was increased, the relative expression levels of TRPC6 and PARP1 proteins were down-regulated, and the relative expression levels of RIPK1, RIPK3 and MLKL proteins were up-regulated in group ES (all P < 0.05). Conclusions hucMSC-Exo may alleviate the necroptosis induced by renal IRI in rat models, which is related to the activation of TRPC6/PARP1 signaling pathway.

Ischemia-reperfusion injury (IRI) refers to the reperfusion injury caused by the recovery of blood supply of ischemic tissues or organs, which commonly occurs in organ transplantation and other surgical procedures. IRI may cause a series of severe clinical issues, such as delayed graft function, acute kidney injury, myocardial infarction, ischemic stroke and circulatory arrest, etc. These events yield high incidence and fatality. At present, no effective solution has been available. Transient receptor potential canonical 6 (TRPC6), a member of Ca²⁺ channel family, is highly expressed in multiple types of cells. It may adjust many physiological functions by regulating intracellular Ca²⁺ concentration, which has become an important target for developing therapeutic drugs for multiple diseases. In this article, research progresses on the introduction and function of TRPC6, the association between TRPC6 and IRI and the therapeutic prospect of TRPC6 targeted drugs in IRI were reviewed, aiming to provide novel insights into the prevention and treatment of IRI during organ transplantation

Objective:To analyze the clinical characteristics of patients with different types of coronavirus disease 2019 (COVID-19).Methods:A total of 272 eligible COVID-19 patients who were admitted to Guangzhou Eighth People′s Hospital, Guangzhou Medical University from January 22 to February 15, 2020 were retrospectively enrolled. General characteristics, the first laboratory examination and imaging data of these patients were collected. According to the clinical classification, there were 236 cases in non-severe group (mild+ common type) and 36 cases in severe group (severe+ critical type). Comparisons between groups were performed by t test, chi-square test or rank-sum test when appropriate. Results:There were 23 males and 13 females in the severe group, 103 males and 133 females in the non-severe group, and the difference was statistically significant ( χ2=5.149, P=0.023). The age of severe group was (60.5±11.2) years, which was higher than that of non-severe group (46.8±15.7) years. The difference was statistically significant ( t=6.43, P<0.01). The lymphocyte (LYM) count, platelet (PLT) count and arterial partial pressure of oxygen (PaO 2) in the severe group were 0.90(0.55, 1.10)×10 9/L, 170.00(143.50, 198.00)×10 9/L and 73.50(69.70, 83.00) mmHg(1 mmHg=0.133 kPa), respectively, which were all lower than those in the non-severe group (1.42(1.09, 1.95)×10 9/L, 187.00(148.00, 230.00)×10 9/L and 96.00(83.20, 108.00) mmHg, respectively). The differences were all statistically significant ( Z=5.59, 2.00 and 5.00, respectively, all P<0.05). The levels of creatine kinase (CK), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), C reaction protein (CRP) and procalcitonin (PCT) in the severe group were 123.00(79.00, 212.00) U/L, 32.10(27.00, 47.40) U/L, 305.50(216.00, 396.00) U/L, 37.02(23.92, 63.66) mg/L and 0.09(0.05, 0.19) μg/L, respectively, which were all higher than those in the non-severe group (68.00(48.00, 103.00) U/L, 20.10(16.70, 26.20) U/L, 179.00(150.00, 222.00) U/L, 26.55(18.11, 36.96) mg/L and 0.04(0.03, 0.06) μg/L respectively), and the differences were all statistically significant ( Z=3.89, 5.60, 5.12, 2.85 and 5.43, respectively, all P<0.01). No significant differences were observed in white blood cell count, creatine kinase isoenzyme and blood lactate between the two groups ( Z=1.53, 0.41 and 1.00, respectively, all P>0.05). Conclusion:Gender, age, LYM count, PLT count, PaO 2, CK, AST, LDH, CRP and PCT could be used to provide reference for clinical classification of COVID-19 patients.

Objective To investigate the imaging features of MRI in patients with invasive ductal carcinoma of breast cancer .Methods 75 patients with breast ductal carcinoma treated by surgical treatment were selected . According to the age,75 patients were divided into young group (≤40 years) with 22 cases and elderly group ( >40 years) with 53 cases.The morphology,location,size,border and edge of the two groups were analyzed .The time signal intensity curve ( TIC) was analyzed.Results The proportion of patients with non -luminal invasive ductal carcinoma of the young group was 54.55％,which was higher than 30.19％ of the elderly group,the difference was statistically significant(χ2 =3.94,P=0.047).The proportion of breast cancer infiltrating ductal carcinoma in the young group was 63.64％,which was higher than 37.74％in the elderly group,the difference was statistically signifi-cant(χ2 =4.21,P=0.040).The proportion of the infarcted ductal carcinoma in the young group was 59.09％,and that in the elderly group was 62.26％,the difference was not statistically significant(χ2=2.19,P=0.14).The proportion of breast invasive ductal carcinoma in the young group was 63.64％, which in the elderly group was 54.72％, the difference was not statistically significant (χ2 =0.13,P=0.72).Ⅰ,ⅡandⅢtype of breast ductal carcinoma TIC in the young group were 0cases,14cases,8cases,respectively,which in the elderly group were 0cases,36cases,17cases, respectively,there was no statistically significant difference in TIC grade between the two groups (χ2 =2.26,P=0.13 ) .Conclusion Breast infiltrating ductal carcinoma is mostly pulmonary lump type ,tumor border is unclear;MRI dynamic enhancement technique for the detection of breast invasive ductal carcinoma can reduce misdiagnosis .