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In order to investigate the problem of formation collapse caused by sand leakage from segmental lining cracks, this paper selected the logical idea of the silo calculation example in PFC3D and used numerical triaxial compression to calibrate the parameters of sand particles. By simulating the changes in the contact force chain between sand particles, the bottom plate load and the porosity of the sand layer during the process of layer collapse caused by sand leakage from segmental lining cracks, the layer subsidence and sand inrush phenomena, sand flow and loss laws of the sand layer due to different openings are studied. The results show that the dynamic process of continuous formation and destruction of the soil vault leads to continuous changes in the contact force between sand particles when the segmental lining cracks cause strata subsidence. The microscopic reason for the sand intrusion disaster was that after the thickness-to-span ratio exceeded the critical value, the soil arch continued to develop towards the top surface and the top surface was connected to the opening, resulting in the inability to form a stable soil arch between the sand particles. During the loss of sand, the change in load on the bottom plate and the change in porosity at the opening corresponded to the process of destruction and formation of the soil arch. Whenever the soil arch was formed, a local peak appeared in the load curve on the bottom plate and the porosity curve at the opening. In the later stage of the sand loss process, as the loss rate increased, the frequency of soil arch formation and destruction accelerated accordingly. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Numerous investigations have indicated a correlation between air pollution (AP) and an elevated ischemic stroke (IS) likelihood. The existing literature does not provide a consensus about the possible link between AP and IS. A two-sample Mendelian randomization (MR) analysis was utilized to systematically measure the causal link between AP and ischemic stroke. Furthermore, the mediating impact of inflammatory factors was also performed by a two-step MR. MATERIALS AND METHODS: A two-sample MR analysis was utilized to examine the AP impact on the incidence of IS. Additionally, a twostep MR approach was carried out to account for possible mediating variables. The indirect impact was determined by employing the product approach, which included multiplying the AP impact on inflammatory factors by the inflammatory factors' impacts on IS. The MR effect was identified through inverse variance-weighted (IVW) meta-analysis of each Wald Ratio. Additionally, complementary studies were conducted using the weighted median and MR-egger approaches. RESULTS: The IVW method with random effects showed that the per unit increase in genetically predicted PM2.5 was linked to the 0.362-fold elevated ischemic stroke risk (OR: 1.362, 95% CI: 1.032-1.796, p=0.029). Furthermore, the IVM technique, incorporating random effects, demonstrated that the per unit increase in genetically predicted PM2.5 was related to an elevated Interleukin (IL)-1β risk (OR: 1.529, 95% CI: 1.191-1.963, p=0.001), IL-6 (OR: 1.498, 95% CI: 1.094-2.052, p=0.012) and IL-17 (OR: 1.478, 95% CI: 1.021-2.139, p=0.038). IL-1β, IL-6, and IL-17 modulated the PM2.5 impact on ischemic stroke, while the proportion mediated by them was 59.5%. CONCLUSIONS: A positive correlation between genetically predicted PM2.5 levels and elevated ischemic stroke risk is mediated by IL-1β, IL-6, and IL-17. [ABSTRACT FROM AUTHOR]

Twenty heavy metals in the ground surface dust and agricultural soil in three different areas, i.e., a former artisanal zinc smelting area, a medium-scale zinc smelting area, and a control area, in Guizhou province southwest China, were investigated to reveal the pollution status of these heavy metals. The results showed that the pollution was most serious in the artisanal zinc smelting area, followed by the medium-scale zinc smelting area, while the control area was relatively clean. Zinc smelting activities had caused environmental contamination for elements such as Ag, As, Bi, Cd, Cu, Hg, In, Pb, Sb, Sn, Zn. Whereas, Co, Cr, Ga, Mo, Ni, Sc, Th, Tl, V were in the natural levels, hinting they were irrelevant to the zinc smelting activities. Concentrations of most heavy metals that come from the zinc smelting were obviously higher in the ground surface dust than that in the agricultural soil. And Cd, Pb, Zn, Ag were the four elements that affected by the zinc smelting activities most.

OBJECTIVE: This study was designed to investigate the role of microRNA-198 in thyroid cancer (TCa) progression. PATIENTS AND METHODS: Quantitative real-time polymerase chain reaction (qRT-PCR) was carried out to examine microRNA-198 and H3F3A levels in tumor tissue specimens and paracancerous ones collected from 50 patients with TCa, and the interplay between microRNA-198 or H3F3A and some clinical indicators or prognosis of TCa patients was analyzed as well. MicroRNA-198 and H3F3A overexpression models were constructed using lentivirus in TCa cell lines TPC-1 and BHP2-7, and the impacts of microRNA-198 on TCa cell functions were evaluated by using cell counting kit-8 (CCK-8), plate clone formation, and transwell assays. Finally, recovery investigations were conducted to explore the underlying mechanisms as well as the interaction between microRNA-198 and H3F3A. RESULTS: QRT-PCR indicated that in tumor tissues of TCa patients, microRNA-198 showed a remarkably lower expression than in adjacent normal tissue samples. Compared with patients with high expression of microRNA-198, those with microRNA-198 low expression had more advanced tumor stage, larger tumor size, higher lymph node metastasis rate, and lower overall survival rate. Meanwhile, the results of research on H3F3A were just opposite to the above observations on microRNA-198. In in vitro cell experiments, overexpression of microRNA-198 significantly weakened the proliferation and migration ability of thyroid tumor cells. Besides, Luciferase reporter gene experiment revealed that H3F3A was a specific target gene for microRNA-198. Moreover, qRT-PCR indicated that H3F3A and microRNA-198 were negatively correlated in thyroid carcinoma tissues. In addition, compared with NC group, overexpression of H3F3A markedly enhanced the migration and proliferative capacity of TCa cells. Lastly, recovery experiment revealed a mutual regulation between microRNA-198 and H3F3A, the two of which may together participate in the malignant progression of TCa. CONCLUSIONS: MicroRNA-198 is remarkably reduced in TCa and inhibits malignant progression of TCa by regulating H3F3A. Meanwhile, microRNA-198 is remarkably associated with pathological stage, tumor size, lymph node metastasis, and poor prognosis of TCa. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Major adverse cardiovascular events occurrences of patients with different cardiac troponin-I (cTnI) levels following percutaneous coronary intervention (PCI) remained controversial. The prognostic relevance and risk factors of PCI-related myocardial infarction (MI) were not very clear as well. PATIENTS AND METHODS: Our study included 249 coronary artery disease patients without preoperative cTnI elevation who successfully accepted PCI from 2013 to 2014. A three-year follow-up was conducted for each patient. The patients were divided into PCI-related MI group and non-PCI-related MI group. Risk factors of PCI-related MI were first explored. The occurrence of MACE was recorded. The prognostic relevance between PCI-related MI (PMI) group and non-PCI-related MI group, as well as different postoperative cTnI levels, were compared. RESULTS: Low-density lipoprotein cholesterol (LDL-C), age, Gensini Score, total stent length, and intra-operative complication were found positively correlated with PCI-related MI occurrence, while hemoglobin and prior PCI history were negatively correlated. After 3-year follow-up, the Kaplan-Meier survival curve showed MACE occurrence was significantly increased in PCI-related MI group. Comparing to patients with normal postoperative cTnI, MACE occurrence was increased in patients with a 10xupper limit of normal (ULN)≤cTnI<70xULN and cTnI≥ 70xULN, while there was no difference in patients with 1xULN≤cTnI<5xULN and 5xULN≤cTnI< 10xULN. Cox proportional hazard regression analysis revealed PMI, NT-proBNP, and left ventricular ejection function (LVEF)<50% were positively correlated with MACE occurrence, while maximum inflation pressure and apoA-I were negatively correlated. CONCLUSIONS: Prognosis of PCI-related MI was poor, as well as in patients with postoperative cTnI≥10xULN. Among the risk factors of PMI, LDL-C, age, Gensini Score, total stent length, and intra-operative complication were positively correlated with PCI-related MI occurrence, while hemoglobin and prior PCI history were negatively correlated. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To investigate the association between microRNA-93-5p (miR-93-5p) and glioma, and to explore the possible mechanisms. PATIENTS AND METHODS: The expression level of miR-93-5p was detected in clinical tissue samples and cell lines. Online prediction websites were used to screen target of miR-93-5p, luciferase reporter assay and Western blot were performed to further confirm. The effects of the miR-93-5p on cell function were determined on U87-MG cells by in vitro experiments. RESULTS: The low expression of miR-93-5p in glioma was confirmed by quantitative Reverse Transcription-Polymerase Chain Reaction (qRTPCR) assay. In Target gene prediction, matrix metalloproteinase-2 (MMP2) was identified as a direct target of miR-93-5p. The subsequent experiments showed that decreased expression of MMP2 resulting from the up-regulation of miR-93-5p obstructed the cell proliferation ability of U87-MG cells, and G0/G1 block occurred during the growth cycle. Further, the invasion and migration ability were also been affected. CONCLUSIONS: Our research emphasized the suppressive function of miR-93-5p in glioma by targeting MMP2, thus providing some novel experimental basis for the treatment of glioma. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To investigate the incidence and risk factors of acute renal failure (ARF) after operation of frozen elephant trunk and total arch replacement for acute thoracic aortic aneurysm and dissection (TAAD) with mild hypothermic circulatory arrest (MHCA), and to analyze the long-term survival rate of the patients with ARF. PATIENTS AND METHODS: From February 2009 to March 2015, patients with acute TAAD accepted operation of frozen elephant trunk and total arch replacement were enrolled. Those patients who were treated with renal replacement treatment (RRT) before the operation were excluded. The age, gender, cardiovascular disease history, preoperative serum creatinine and extracorporeal circulation duration in operation were recorded. On the basis of requiring RRT after TAAD operation, the patients were divided into ARF group and non-ARF group. The risk factors of ARF after TAAD operation were assessed by univariate and multivariate analysis. After completion of clinical follow-up, Kaplan-Meier curve was drawn to analyze five-year survival. RESULTS: A total of 524 patients were included in the study. 51 cases of them got postoperative ARF. The incidence was 9.7%. The mortality rate of ARF group in the hospital was significantly higher than non-ARF group (25.5% vs. 3.6%; p<0.001). Univariate analysis showed that there was statistically significant difference in the age, gender, hypertension history, preoperative serum creatinine ≥200 μmol/L, extracorporeal circulation duration ≥260 min and combined with coronary artery bypass surgery simultaneously (p<0.05). Multiple logistic regression analysis showed that there were three independent risk factors of ARF after the operation, including hypertension (p=0.031, OR=2.377), preoperative serum creatinine ≥200 μmol/L (p=0.005, OR=4.451) and extracorporeal circulation duration ≥260 min (p=0.002, OR=3.295). The total five-year survival rate of ARF group after the operation was 56%. There was no statistically significant difference in the five-year survival rate between preoperative serum creatinine ≥200 μmol/L group and <200 μmol/L group (p>0.05). CONCLUSIONS: The incidence of ARF after the operation was 9.7%. Preoperative serum creatinine ≥200 μmol/L, hypertension history and extracorporeal circulation duration ≥260 min were independent risk factors of ARF after the operation. The five-year survival rate of ARF after the operation was 56%. The preoperative serum creatinine level had no influence on the postoperative long-term survival. [ABSTRACT FROM AUTHOR]