Treatment of benign prostatic hyperplasia with finasteride: Evidence from a meta-analysis

Purpose: To clarify the usefulness and safety of finasteride in the treatment of patients with benign prostatic hyperplasia (BPH) compared to placebo group or controls.Methods: In a meta-analysis, PubMed and Web of Science were searched to include relevant studies. The results were combined with a random effect model. Publication bias was evaluated using Egger regression asymmetry test.Results: Fourteen publications involving 17,364 patients were included in the study. Pooled results indicated that International Prostate Symptom Score (IPSS) in the finasteride group was lower [weighted mean difference (WMD) = -0.77, 95% CI= -0.97 to -0.57] compared to the placebo group. The usefulness of finasteride was higher in total prostate volume (TPV) [WMD= 0.13, 95%CI= 0.00 to 0.26] but lower in serum DHT [WMD= -1.18, 95%CI= -1.51 to -0.86] when compared to the placebo group. Drug-related adverse event was higher in the finasteride treatment group when compared to placebo group [summary RR= 1.95, 95%CI= 1.31-2.90].Conclusion: Finasteride could improve the symptom score (IPSS and TPV) and reduce serum DHT. However, the potential adverse events, especially the drug-related adverse events in Finasteride treatment should be attention.Keywords: Benign prostatic hyperplasia, Finasteride, Meta-analysi

Perfect anomalous splitter by acoustic meta-grating

As an inversely designed artificial device, metasurface usually means densely arranged meta-atoms with complex substructures. In acoustics, those meta-atoms are usually constructed by multi-folded channels or multi-connected cavities of deep sub-wavelength feature, which limits their implementation in pragmatic applications. We propose here a comprehensive concept of a perfect anomalous splitter based on an acoustic meta-grating. The beam splitter is designed by etching only two or four straight-walled grooves per period on a planar hard surface. Different from the recently reported reflectors or splitters, our device can perfectly split an incident wave into different desired directions with arbitrary power flow partition. In addition, because ultrathin substructures with thin walls and narrow channels are avoided in our design procedure, the proposed beam splitter can be used for waves with much shorter wavelength compared to the previous suggested systems. The design is established by rigorous formulae developed under the framework of the grating theory and a genetic optimization algorithm. Numerical simulation and experimental evidence are provided to discuss the involved physical mechanism and to give the proof-of-concept for the proposed perfect anomalous acoustic splitter.Comment: 5 figure

IL-8 Enhances Therapeutic Effects of BMSCs on Bone Regeneration via CXCR2-Mediated PI3k/Akt Signaling Pathway

Background/Aims: Tissue engineering bone transplantation with bone marrow mesenchymal stem cells (BMSCs) is an effective technology to treat massive bone loss, while molecular regulation of the bone regeneration processes remains poorly understood. Here, we aimed to assess the role of interleukin-8 (IL-8) in the recruitment of host cells by seeded BMSCs and in the bone regeneration. Methods: A transwell assay was performed to examine the role of IL-8/CXCR1/CXCR2/PI3k/Akt on the migration potential of hBMSCs. The in vitro chondrogenic differentiation of hBMSCs was assessed by examination of 2 chondrogenic markers, Sox9 and type 2 collagen (COL2). mBMSCs were used in tissue engineered bone (TEB) with/without IL-8 implanted into bone defect area with CXCR2 or Akt inhibitors. Density and Masson staining of the regenerated bone were assessed. The chondrogenesis was assessed by expression levels of associated proteins, Sox9 and COL2, by RT-qPCR and by immunohistochemistry. Results: IL-8 may trigger in vitro migration of hBMSCs via CXCR2-mediated PI3k/Akt signaling pathway. IL-8 enhances osteogenesis in the TEB-implanted bone defect in mice. IL-8 induces chondrogenic differentiation of hBMSCs via CXCR2-mediated PI3k/Akt signaling pathway in vitro and in vivo. Conclusions: IL-8 enhances therapeutic effects of MSCs on bone regeneration via CXCR2-mediated PI3k/Akt signaling pathway

Tunable solid acoustic metamaterial with negative elastic modulus

International audienceWe report in this letter on a tunable solid acoustic metamaterial with negative elastic modulus by means of piezoelectric composite. The theoretical formulae for one-dimensional layer-stacked metamaterial embedding a piezoelectric material by means of external shunted inductors are presented. The acoustic band structure of the composite is calculated by the transfer matrix method. Results show that a band gap can be opened and tuned by the resonant behavior of the LC circuit. It is found further by the formulae that piezoelectric material with large piezoelectric constant and small elastic modulus will be beneficial for opening a wide band gap. The effective elastic constant of the system is also calculated by the unit-cell-boundary-averaging method. Result shows that the system behaves as an effective medium with a negative elastic modulus. This property is quite different from the typical solid metamaterial achieved by dispersing heavy inclusions coated with a soft layer into a matrix for which only the negative mass density can be obtained

Microscopic Stress Sensitivity Analysis with In Situ SEM Study and Digital Core Deformation Simulation

Rock stress sensitivity is typically investigated macroscopically. In contrast, a new method combining in situ Scanning Electronic Microscope (SEM) study and digital core deformation simulation is developed in this paper, providing an effective way to investigate the relationship between microstructural deformation and decreasing permeability. The simulation method might replace in situ SEM study under certain scenarios. First, the in situ SEM study was implemented, and the microstructure deformations of rock samples during uniaxial loading were observed and recorded. The SEM images at different stress states were analyzed by digital image correlation (DIC) technique to investigate the principles of these deformations. A deformation simulation method was correspondingly proposed. The simulation effectiveness was demonstrated by comparing the simulation and the in situ SEM study results. To validate the simulation method for the three-dimensional (3D) digital core, porosity-permeability integrated measurements under triaxial stresses were conducted to obtain macroscale data under different stress states for a tight sandstone sample. A 3D digital core was reconstructed by micro-CT imaging with the same rock sample. Under the constraints of the measured porosity changes, the 3D digital core deformation was simulated. A series of simulated cores at different stress states were used for pore network model extraction, and the corresponding permeability was calculated. A comparison of the permeability changes of the simulation and porosity-permeability integrated measurements indicated consistently that the simulation method can characterize the 3D digital core stress sensitivity. In addition, the in situ SEM study results revealed that the throats deformed more severely than the pores by generating the pore and throat diameter frequency distributions at different stress states. Therefore, we concluded that throat deformation is more critical than pore deformation for permeability reduction

Computation of plate wave dispersion diagrams and surface wave velocities without explicit boundary conditions

International audienceWe discuss the computation of the band structure of plate waves using the plane wave expansion (PWE) method. This method is generally used to formulate eigenvalue problems to compute dispersion diagrams for solid-solid phononic crystals. We show how the free surface boundary condition can be included implicitly in the form of the PWE solution, thus leading to an efficient eigenvalue problem. This generic method for wave dispersion is non-iterative and does not require an initial guess for the solution. Furthermore, surface acoustic wave velocities can be estimated from the slowest wave for large wave vectors. Examples for a single plate and a multilayer plate are given, and extension to piezoelectric materials is discussed