Objective: To observe the protective effect of ischemic post-conditioning on myocardial reperfusion injury with the potential mechanism in experimental rabbits. Methods: A total of 36 healthy New Zealand rabbits were divided into 6 groups:①Sham group,②Ischemic reperfusion control (CON) group,③Myocardial ischemic post-conditioning (MpostC) group,④Remote ischemic post-conditioning (RPostC) group,⑤MPostC+5-HD group,⑥RPostC+5-HD group.n=6 in each group. The ischemic reperfusion injury model was established by left ventricular descending artery occlusion for 45 min followed by reperfusion for 120 min. Bilateral external iliac artery was occluded for 5 min to induce the short skeletal muscle ischemia. The indexes of cardiac function and plasma CK , LDH activities were measured at baseline, end of ischemia and 1, 2 h after reperfusion respectively, the sizes of myocardial infarction (MI) were examined and compared among different groups. Results: ①Compared with CON group, the indexes of cardiac function were improved in MPostC and RPostC groups at 1, 2 h after reperfusion,P<0.05, and compared with MPostC group and RPostC group, the indexes of cardiac function were improved in MPostC+5-HD and RPostC+5-HD groups,P<0.05.②Compared with CON group, plasma CK, LDH activities were decreased in MPostC and RPostC groups at 2 h after reperfusion,P<0.05, and compared with MPostC group and RPostC group, the CK, LDH activities were increased in MPostC+5-HD and RPostC+5-HD groups,P<0.05.③The ischemic ranges and areas were similar between CON group and the other 5 groupsP>0.05. The MI ranges and areas in MPostC and RPostC groups were much less than that in CON group,P<0.05, and compared with MPostC group and RPostC group, the MI ranges and areas increased in MPostC+5-HD and RPostC+5-HD groups,P<0.05. The MI ranges and areas were similar between CON group and MPostC+5-HD, RPostC+5-HD groups,P>0.05. Conclusion: Classical ischemic post-conditioning and remote organ ischemic post-conditioning both have protective effect on myocardial reperfusion injury in experimental rabbit, which might be related to the activation of mitochondrial ATP-sensitive potassium channels.

Objective: To investigate the preventive effect of alprostadil (prostaglandin E1) combining hydration therapy on contrast induced nephropathy (CIN) after percutaneous coronary intervention (PCI) in elder patients. Methods: A total of 175 patients with coronary artery disease (CAD) elder than 75 years received PCI in our hospital from 2011-03 to 2014-03 were retrospectively studied, those including 122/175 (69.71 %) with male gender. The patients were at the mean age of (74.7 ± 3.9) years and randomly allocated into 2 groups: Control group, based on routine treatment, the patients received regular hydration of intravenous normal saline 1 ml/(kg?h) at 6 hours prior and 12 hours after PCI,n=84 and Alprostadil+hydration group, based on routine treatment and regular hydration, the patients received intravenous alprostadil 10μg in 100ml normal saline twice a day at 1 day prior PCI and the 3rd day after PCI,n=91. The serum levels of creatinine (SCr) were examined prior PCI and 3 days continuously after PCI, creatinine clearance rates (Ccr) were calculated and the CIN occurrence rates were compared between 2 groups. Results: At the 3rd day after PCI, the mean SCr level in Alprostadil+hydration group (92.08 ± 21.65) μmol/L was lower than Control group (99.43 ± 22.77) μmol/L,P<0.05, the mean Ccr level in Alprostadil+hydration group (63.78 ± 20.58) ml/min was higher than Control group (57.09 ± 22.31) ml/min,P<0.05. The occurrence rate of CIN after PCI was higher in Control group (13.1%, 11/84 patients) than Alprostadil+hydration group (3.3%, 3/91 patients),P<0.05. Conclusion: Alprostadil combining hydration therapy may obviously protect renal function and reduce the incidence rate of CIN in elder CAD patients after PCI treatment.

AIM:Toinvestigatetheeffectofnicotinicacidamide(NAA)ontheinfusiondamageofhuman umbilical cord mesenchymal stem cells ( hUC-MSCs) under the condition of instant blood-mediated inflammatory reaction ( IBMIR) .METHODS:Normal peripheral blood without anticoagulant at volume of 2.7 mL was mixed with 0.3 mL phys-iological saline (as blank group), CFSE labeled hUC-MSCs (1 ×106 cells in 0.3 mL as MSC group) and CFSE labeled hUC-MSCs (1 ×106 cells in 0.3 mL) preprocessed with NAA at concentration of 10 mmol/L for 24 h ( as MSC+NAA group) , respectively.The mixture was immediately injected into the improved Chandler Loop model, placed in 37℃water bath, and then started the peristaltic pump at the speed of 20 mL/min for 1 h.The number of CFSE labeled hUC-MSCs, platelets, white blood cells were counted and the concentration of complement C3a was measured before and after cycling, respectively.RESULTS: After 1 h circulation, the platelet dissipation rate were ( 29.96 ±10.88 )% in blank group, (77.76 ±19.29)% in MSC group all and (50.13 ±18.10)% in MSC +NAA group; and the leukocyte counts were (37.82 ±13.81)%in blank group, (64.57 ±17.08)% in MSC group and (41.52 ±17.26)% in MSC+NAA group. Compared with blank group, the differences of the dissipation rates in MSC group and MSC+NAA group all had statistical significance.The hUC-MSCs relative survival rate in MSC+NAA group was higher than that in MSC group.C3a concentra-tions in blank group, MSC group and MSC+NAA group were (206.27 ±58.10), (230.47 ±39.61) and (208.37 ± 40.66) μg/L, respectively.CONCLUSION:Co-circulating the mixture of hUC-MSCs with normal peripheral blood with-out anticoagulant in the improved Chandler Loop for 1 h depletes a large number of hUC-MSCs and blood components, and increases C3a, suggesting that this model can induce IBMIR.NAA has a protective effect on the hUC-MSCs in the infusion damage by inhibiting IBMIR, reducing the wastage of the blood components and enhancing the survival rate of the hUC-MSCs.

AIM:To investigate the influence of continuous subculturing of human umbilical cord mesenchymal stem cells (hUC-MSCs) on the mRNA expression of all 23 family members of NOD-like receptors (NLRs), and to search for the way of improving the subculture quality of hUC-MSCs and increasing the quantity and safety in the experimental and clinical application .METHODS:Neonatal umbilical cord was collected to isolate and purify the hUC-MSCs with the colla-genase II digestion and adherence screening methods .These cells were continuously subcultured .The hUC-MSCs at pas-sage 3 and passage 28 were identified by flow cytometry and induced differentiation .The mRNA expression of NLRs in the passage 3 and passage 28 hUC-MSCs was detected by RT-qPCR.RESULTS: The cell phenotypes of both passage 3 and passage 28 hUC-MSCs were CD29 +/CD44 +/CD105 +/CD31 -/CD34 -/CD40 -/CD45 -/CD106 -/HLA-DR-, and both of the cells were induced into osteoblasts and adipocytes , which were conformed to the criteria of International Society for Cellular Therapy to define MSCs .All the NLR family members were expressed in passage 3 hUC-MSCs.NOD1, NLRC4, NLRC5, NLRP1, NLRP3, NLRP10, NAIP, NLRX1 and APAF1 at mRNA levels were highly expressed , and the rest were lowly expressed.When hUC-MSCs were subcultured to passage 28, NLRP10 mRNA was increased, NLRC5 mRNA and NLRX1 mRNA were hardly changed , and all of the rest members were decreased .The difference of NLRP1 mRNA expres-sion between passage 3 and passage 28 hUC-MSCs was observed with statistical significance (P<0.05).CONCLU-SION:The effects of subculturing on the expression of NLR family in hUC-MSCs are pleiotropic .It requires further investi-gation to confirm whether these effects are related to the proliferation , differentiation and immunomodulation of MSCs .

Objective: To provide basis for the preparation process study by establishing an HPLC determination method for nicotinate-curcumin ester.Methods: A C18 column(250 mm×4.6 mm,5 μm) was used at 30℃ with the mobile phase of acetonitrile-0.5% acetic acid glacial(65∶35) at a flow rate of 1.0 ml·min-1.The UV detection wavelength was 280 nm.Results: The good linear relationship of nicotinate-curcumin ester was shown within the range of 5.200-104.000 μg · ml-1(r=0.9999 4), The average recovery of nicotinate-curcumin ester and its nanoparticles was 100.1% and 100.9%with RSD of 1.260% and 0.995 0%(n=6), respectively.Conclusion: The method is convenient, accurate and reproducible, and suitable for the determination of nicotinate-curcumin ester nanoparticles and the studies on the preparation technology.

Objective:To analyze the clinicopathological features, diagnosis, and treatment of anorectal malignant melanoma (ARMM), and to explore its prognostic factors and misdiagnosis. Methods:A total of 36 patients with ARMM were enrolled in this study from January 2000 to November 2016 in Nanfang Hospital, Zhujiang Hospital, and Guangdong Provincial Hospital of Traditional Chinese Medicine. Results: The clinical manifestations of ARMM were not specific. The odds of misdiagnosis were as high as 52.8% in this study. The 1-and 3-year survival rates were 75%and 35%, respectively, with median survival time of 24.51 months. Survival rate was correlated with tumor size, invasion depth, clinical stage, and lymph node metastasis (P<0.05), but was not related to patient age and gender. The median survival time of the three groups of patients (surgery alone, surgery-based combination therapy, untreated) were 39.21, 26, and 15 months. The difference was not statistically significant. No difference in survival was found between patients under-going abdominoperineal resection and wide local excision. Conclusion:ARMM has poor prognosis and is easily misdiagnosed as a ma-lignant tumor. The prognostic factors are tumor size, invasion depth, clinical stage, and lymph node metastasis. Surgical treatment can extend survival. To avoid misdiagnosis and prolong survival, early diagnosis and early treatment are recommended.

Objective:To determine the equilibrium solubility and the apparent oil/water partition coefficients of nicotinate-curcu-min ester,so as to provide basis for the new formula design. Methods:Nicotinate-curcumin ester was dissolved in buffer solution with pH of 1.2-7.8. HPLC was used to detect the equilibrium solubility of nicotinate-curcumin ester in various solutions. The apparent oil/water partition coefficients in octanol-water and octanol-buffer solution system were measured by a shaking-flask method. Results:The solubility of nicotinate-curcumin ester in pH 6.8 was the highest. The apparent oil-water partition coefficients of nicotinate-curcumin ester in pH 1.2,5.8,6.5 and 7.8 were lgPapvalues within the range(lgPap=1.69-1.98) beneficial to the absorption in vivo. But in pH 2,5 and 6.8,the lgPapvalues were greater than 2 with strong lipophilicity. Conclusion:The equilibrium solubility as well as ap-parent oil/water partition coefficients of nicotinate-curcumin ester is greatly influenced by the pH value of media. In the pH value with relatively high solubility,lipophilicity is stronger,suggesting it is difficult to be absorbed by the body and needs to be further studied on dosage forms.

Objective:To compare the effect of O-arm assisted and free-hand pedicle screw placement in the treatment of AO type C thoracolumbar fracture.Methods:A retrospective cohort study was used to analyze the clinical data of 34 patients with type C thoracolumbar fracture admitted to Henan Provincial People′s Hospital from January 2018 to June 2021, including 23 males and 11 females; aged 42-63 years [(50.4±7.4)years]. The fracture was located at T 11 in 4 patients, T 12 in 10, L 1 in 12, L 2 in 6, T 11~12/L 1 in 1 and T 12/L 1 in 1. Posterior reduction and internal fixation was carried out for all patients, of whom 18 were treated with O-arm assisted pedicle screw placement (navigation group) and 16 with free-hand pedicle screw placement (free-hand group). The operation time, single screw placement time, intraoperative bleeding volume, operation mode and screw placement accuracy were compared between the two groups. The kyphotic Cobb angle, visual analogue score (VAS) and American Spinal Injury Association (ASIA) score were compared between the two groups before operation, at 1 week after operation, at 3 months after operation and at the last follow-up. Postoperative complications were observed. Results:All patients were followed up for 12-29 months [(16.8±6.1)months]. There was no significant difference between the two groups in the operation time, intraoperative bleeding volume and operation mode (all P>0.05). The single screw placement time was (9.4±1.6)minutes in navigation group, but was (10.8±1.5)minutes in free-hand group ( P<0.05). The screw placement accuracy was 97.4% in navigation group, but was 81.5% in free-hand group ( P<0.01). The kyphotic Cobb angle and VAS had no significant differences between the two groups before operation (all P>0.05). The kyphotic Cobb angle in navigation group and free-hand group was (4.3±1.1)° and (5.9±1.1)° at 1 week after operation, (4.4±1.2)° and (5.7±1.3)° at 3 months after operation, and (4.4±1.2)° and (6.8±0.9)° at the last follow-up, decreased significantly from that before operation [(21.8±3.1)°, (22.2±3.2)°] (all P<0.01). The kyphotic Cobb angle in navigation group was significantly lower than that in free-hand group at 1 week, 3 months after operation and at the last follow-up (all P<0.01). The VAS in navigation group and free-hand group was (3.2±0.7)points and (4.1±0.7)points at 1 week after operation, (2.4±0.6)points and (3.0±0.8)points at 3 months after operation, and (1.8±0.9)points and (2.6±0.7)points at the last follow-up, decreased significantly from that before operation [(8.4±0.8)points, (8.3±0.9)points] (all P<0.01). The VAS in navigation group was significantly lower than that in free-hand group at 1 week, 3 months after operation and at the last follow-up (all P<0.01). The ASIA score showed no significant difference within and between the two groups before operation, at 1 week, 3 months after operation and at the last follow-up (all P>0.05). Postoperative incision infection occurred in 1 patient in both groups ( P>0.05). Implant failure such as loosening or displacement was not observed in navigation group, and only occurred in 2 patients in free-hand group ( P>0.05). Conclusion:Compared with free-hand pedicle screw placement, O-arm assisted pedicle screw placement in the treatment of AO type C thoracolumbar fracture has advantages of rapid and accurate screw placement, good reduction and notable pain relief.

Radiotherapy is a first-line treatment for a variety of malignant tumors by inducing DNA damage to kill tumor cells. However, tumor cells have different sensitivities to radiotherapy, ultimately leading to different therapeutic effects. Histone acetylation, regulated by histone acetyltransferase (HAT) and histone deacetylase (HDAC), is involved in the regulation of cell radiation sensitivity by influencing DNA damage repair. The main mechanisms are recruiting DNA repair related proteins and mediating chromatin dynamic changes. In this article, the role of histone acetylation modification in tumor radiotherapy was reviewed, aming to provide the basis for the radiotherapy sensitization strategy based on histone acetylation.

Objective To propose a dual-domain CBCT reconstruction framework(DualSFR-Net)based on generative projection interpolation to reduce artifacts in sparse-view cone beam computed tomography(CBCT)reconstruction.Methods The proposed method DualSFR-Net consists of a generative projection interpolation module,a domain transformation module,and an image restoration module.The generative projection interpolation module includes a sparse projection interpolation network(SPINet)based on a generative adversarial network and a full-view projection restoration network(FPRNet).SPINet performs projection interpolation to synthesize full-view projection data from the sparse-view projection data,while FPRNet further restores the synthesized full-view projection data.The domain transformation module introduces the FDK reconstruction and forward projection operators to complete the forward and gradient backpropagation processes.The image restoration module includes an image restoration network FIRNet that fine-tunes the domain-transformed images to eliminate residual artifacts and noise.Results Validation experiments conducted on a dental CT dataset demonstrated that DualSFR-Net was capable to reconstruct high-quality CBCT images under sparse-view sampling protocols.Quantitatively,compared to the current best methods,the DualSFR-Net method improved the PSNR by 0.6615 and 0.7658 and increased the SSIM by 0.0053 and 0.0134 under 2-fold and 4-fold sparse protocols,respectively.Conclusion The proposed generative projection interpolation-based dual-domain CBCT sparse-view reconstruction method can effectively reduce stripe artifacts to improve image quality and enables efficient joint training for dual-domain imaging networks in sparse-view CBCT reconstruction.