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Pelvic organ prolapse (POP) is a common disorder among women that negatively affects women's quality of life. Early growth response 2 (EGR2) is a transcription factor that regulates cell growth. The present study aimed to explore the role of EGR2 in POP progression and provided a new target for the treatment and prevention of POP. Firstly, we extracted primary vaginal anterior wall fibroblasts from POP tissues and non-POP tissues and then constructed an EGR2-silencing lentivirus for further study. Immunoblotting, qPCR, TUNEL assay, CCK-8 assay, dual luciferase assay, and ELISA assay were carried out. EGR2 expression was much higher in POP tissues than in control tissues, and EGR2 expression positively correlated with cytokine signaling 3 (SOCS3) expression. Knockdown of EGR2 increased cell proliferation, upregulated PCNA expression, and reduced apoptosis in POP fibroblasts. Moreover, we found that the knockdown of EGR2 increased COL1A1, COL3A1, and Elastin expression and decreased MMP2 and MMP9 activities, and knockdown of EGR2 increased TGF-β/Smad pathway activity in POP fibroblasts. Interestingly, the results of dual luciferase assay demonstrated that EGR2 was able to increase SOCS3 transcriptional activity. EGR2 knockdown alleviated the apoptosis of POP fibroblasts by reducing SOCS3 expression and improving the proliferation and collagen synthesis of POP fibroblasts. Overall, our study illustrated that EGR2 was highly expressed in POP tissues, and knockdown of EGR2 alleviated apoptosis and reduced matrix degradation in POP fibroblasts. This study might provide a new insight into the pathogenesis of POP. [ABSTRACT FROM AUTHOR]

In this paper, the dynamics of a ratio-dependent predator–prey model with strong Allee effect and Holling IV functional response is investigated by using dynamical analysis. The model is shown to have complex dynamical behaviors including subcritical or supercritical Hopf bifurcation, saddle-node bifurcation, Bogdanov–Takens bifurcation of codimension-2, a nilpotent focus or cusp of codimension-2. The codimension-2 Bogdanov–Takens bifurcation point acts as an organizing center for the whole bifurcation set. The coexistence of stable and unstable positive equilibria, homoclinic cycle is also found. Our analysis shows that the ratio-dependent model may collapse suddenly due to certain parameter variation, i.e. the numbers of predator and prey will decrease sharply to zeroes after undergoing a short time of sustained oscillations with small amplitudes. Of particular interest is that the coalescence of saddle-node bifurcation point and Hopf bifurcation point may indicate the occurrence of relaxation oscillations and the critical state of extinction of predator and prey. Numerical simulations and phase portraits including one-parameter bifurcation curve and two-parameter bifurcation curves are given to illustrate the theoretical results. [ABSTRACT FROM AUTHOR]

Natural damage such as internal cracks, pores, and discontinuous surfaces of rocks induces the formation, expansion, and interaction of mesofractures until macroscopic failure under the action of freeze-thaw and load. The failure process is the evolution of self-organization and has localization characteristics. The CT scanning test of sandstone with different freezing and thawing cycles was carried out. According to the theory of cellular automata analysis, combined with CT image processing technology, the numerical model of the mesostructure of the sandstone constructed with natural damage, and the numerical simulation test of the Brazilian splitting failure of natural damage sandstone was completed under freezing and thawing. The results show that the combination of CT image processing technology and CASRock numerical simulation software can dynamically describe the whole process of initial damage propagation, new crack generation, and penetration of rock containing natural damage under tension in a freeze-thaw environment. Due to random and disordered natural damage inside the rock, gradually changing to an orderly state under freezing and load, the rock shows discontinuous deformation after the plastic deformation reaches a certain degree and gathers at the initial damage expansion. The fracture process of natural damaged rock under freezing and load has continuous-discontinuous deformation characteristics. The existence of initial rock damage causes the rock's localized deformation and failure characteristics. The form and size of the initial damage determine the direction of development of the surface of the sandstone fracture and the coalescence of the crack. The initial damage area of sandstone is expanded due to the freeze-thaw cycle. After loading, the local deformation and failure characteristics caused by initial damage have delay characteristics for penetration of the main cracks in the sandstone, which determines the formation and development direction of secondary cracks in the rock failure process. [ABSTRACT FROM AUTHOR]

Background: Retroperitoneal ectopic pregnancy (REP) is an extremely rare type of ectopic pregnancy, with a total of less than 32 cases reported in the English literature. Early diagnosis of REP is very difficult and all treatments entail a high risk of life-threatening complications.Case Presentation: A 29-year-old nulliparous woman presented a history of 50-day amenorrhea and 7-day upper abdominal pain without vaginal spotting. The serum beta-human chorionic gonadotropin (β-hCG) value was 65,004 m-international units per milliliter (mIU/mL), but no intrauterine gestational sac was found via transvaginal sonography (TVS). Then transabdominal ultrasonography (TAS) and abdominal contrast-enhanced computer tomography (CT) identified a retroperitoneal ectopic pregnancy (REP) tightly adjacent to the inferior vena cava and the abdominal aorta. After consultation from a multidisciplinary team, systemic methotrexate (MTX, intramuscular 20 mg daily for 5 consecutive days) combined with ultrasound-guided local potassium chloride solution injection into the gestational sac was scheduled firstly for the patient. However, serum β-hCG continued to increase and the patient experienced worsening abdominal pain. Laparotomy was performed jointly by a gynecologist and a vascular surgeon. During the operation, the gestational sac with fetal bud measuring about 4.5 × 4.0x3.0 cm, tightly adherent to the surface of inferior vena cava and the left side of abdominal aorta, was carefully dissociated out from the surrounding tissues and removed en bloc. Histopathology examination confirmed the diagnosis of REP. The patient recovered uneventfully and her serum β-hCG returned to normal range on the 23th postoperative day.Conclusions: Considering the possibility of REP and combined radiological examinations, such as ultrasonography and CT, are crucial for the early diagnosis of this rare condition. A multidisciplinary team is necessary to treat REP. [ABSTRACT FROM AUTHOR]

Renal cell carcinoma during pregnancy is extremely rare, but it is the commonest urological malignancy reported in pregnancy. Currently, no uniform domestic or international diagnostic or treatment criteria exist for these patients, so their diagnosis and treatment are challenging for urologists. The health and reproductive needs of these patients have improved in recent years because of the continuous development of medical technology. This article reviews the epidemiology, risk factors, diagnosis, treatment, and prognosis of renal cell carcinoma during pregnancy. [ABSTRACT FROM AUTHOR]

Background: Pelvic organ prolapse (POP) lowers the quality of life in elderly women, and there have been no studies on its role in the pathogenesis of POP. The purpose of this study is to investigate the effect of β‐catenin on proliferation and collagen anabolism in human vaginal fibroblasts (HVFs). Materials and Methods: The adherence and differential adherence methods were used to culture and purify HVFs. RNA interference was applied to knockdown β‐catenin and lithium chloride was used to activate Wnt/β‐catenin signaling pathway. β‐catenin nuclear translocation was tested by immunofluorescence, and HVF proliferation was detected by performing MTT assays. Results: The expression of β‐catenin, phosphorylated‐β‐catenin, phosphorylated‐glycogen synthase kinase 3β (p‐GSK3β), collagen I, matrix metalloproteinase 2 (MMP2), and tissue‐derived inhibitors of metalloproteinases 2 (TIMP2) was assessed by western blot analysis. The expression of β‐catenin and collagen I was lower in HVFs of POP group than that of control group. The proliferation rate of HVFs in POP group was lower than that in control group. Knockdown of β‐catenin decreased the cell proliferation rate and the expression of collagen I. Lithium chloride can activate the Wnt/β‐catenin signaling pathway. Conclusion: β‐catenin participates in the proliferation and collagen I synthesis of HVFs. The decrease of β‐catenin expression may be closely related to the occurrence, and development of POP. LiCl can activate the Wnt/β‐catenin signaling pathway in HVFs and thus increase HVFs proliferation and collagen synthesis. [ABSTRACT FROM AUTHOR]

Due to the double-salient structure of the switched reluctance motor (SRM) and highly magnetic saturation, its rotor position shows highly nonlinear function with phase current and flux linkage. Therefore, the establishment of accurate and small-scale SRM rotor position model is crucial to realize SRM position sensorless control. This paper is based on SRM flux characteristics collected by actual measurement, then adopts back-propagation neural network (BPNN) with improved algorithm and radial basis function neural network (RBFNN), respectively, to build SRM rotor position model. It is concluded that the model built by BPNN based on the Levenberg–Marquardt algorithm has smaller network structure and higher accuracy than RBFNN. In order to optimize BPNN model further, two kinds of pretreatment methods are used to study SRM rotor position model, respectively, and the modeling results of these two methods are compared. Adopting pretreatment method could reduce scale and improve accuracy to achieve the model optimization. After initial rotor position was estimated accurately without rotor position sensor, experiments are performed based on a three-phase 12/8 SRM. The experimental results verify that the BPNN model of rotor position for SRM based on a pretreatment method could be applied to SRM position sensorless control. [ABSTRACT FROM AUTHOR]

Hydride artefacts are commonly induced by the TEM sample preparation process in Zirconium alloys as hydrogen-sensitive metals, including electron polishing and focused ion beam (FIB) technology. In the research, we present the application of chemical polishing with a solution of 10HF:45HNO3:45H2O to prepare the disk samples for TEM observation in zirconium alloys. The thinning efficiency of chemical polishing is 25 μm per minute. XRD patterns indicate that the chemical polishing actually eliminates the macro- and micro-stress induced by mechanical grinding. TEM observation demonstrates that chemical polishing reduces the amount of hydride artefacts, especially hydrides with large size. It is proposed that induced stress provides driving force for hydride artefact formation. Compared with traditional mechanical grinding, the advantages of chemical polishing are high efficiency, free of induced stress, less induced hydride artefacts and bend contours. [ABSTRACT FROM AUTHOR]

This work presents numerical well testing interpretation model and analysis techniques to evaluate formation by using pressure transient data acquired with logging tools in crossflow double-layer reservoirs by polymer flooding. A well testing model is established based on rheology experiments and by considering shear, diffusion, convection, inaccessible pore volume (IPV), permeability reduction, wellbore storage effect, and skin factors. The type curves were then developed based on this model, and parameter sensitivity is analyzed. Our research shows that the type curves have five segments with different flow status: (I) wellbore storage section, (II) intermediate flow section (transient section), (III) mid-radial flow section, (IV) crossflow section (from low permeability layer to high permeability layer), and (V) systematic radial flow section. The polymer flooding field tests prove that our model can accurately determine formation parameters in crossflow double-layer reservoirs by polymer flooding. Moreover, formation damage caused by polymer flooding can also be evaluated by comparison of the interpreted permeability with initial layered permeability before polymer flooding. Comparison of the analysis of numerical solution based on flow mechanism with observed polymer flooding field test data highlights the potential for the application of this interpretation method in formation evaluation and enhanced oil recovery (EOR). [ABSTRACT FROM AUTHOR]