[Current application and prospect of accurate navigation technology in orthopaedic trauma].

In the past decades,a dramatic development of navigation technology in orthopaedic surgery has been witnessed. By assisting the localization of surgical region,verification of target bony structure,preoperative planning of fixation,intraoperative identification of planned entry point and direction of instruments or even automated insertion of implants,its ability and potential to reduce operation time,intraoperative radiation,surgical trauma,and improve accuracy has been proved. However,in contrast to the widespread use of navigation technology in arthroplasty,orthopaedic tumor,and spine surgery,its application in orthopaedic trauma is relatively less. In this manuscript,the main purpose is to introduce the technical principles of navigation devices,outline the current clinical application of navigation systems in orthopaedic trauma,analyze the current challenges confronting its further application in clinical practice and its prospect in the future.

CircVCAN regulates the proliferation and apoptosis of osteoarthritis chondrocyte through NF-κB signaling pathway.

This paper presents both inaccuracies and mistakes. Therefore, the article "CircVCAN regulates the proliferation and apoptosis of osteoarthritis chondrocyte through NF-κB signaling pathway, by H.-R. Ma, W.-B. Mu, K.-Y. Zhang, H.-K. Zhou, R.-D. Jiang, L. Cao, published in Eur Rev Med Pharmacol Sci 2020; 24 (12): 6517-6525-DOI: 10.26355/eurrev_202006_21635-PMID: 32633338" has been withdrawn. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/21635.

CircVCAN regulates the proliferation and apoptosis of osteoarthritis chondrocyte through NF-κB signaling pathway.

OBJECTIVE: Osteoarthritis is one of the chronic diseases with a high incidence. CircRNA is a circular non-coding RNA. Studies show that CircRNA is closely relevant to the pathogenesis of OA chondrocytes. However, the specific principle is still unclear. PATIENTS AND METHODS: 38 patients with OA tissues and 38 patients with normal knee cartilage in our hospital were selected, respectively. The mRNA expression levels of CircVCAN were measured by quantificational real-time polymerase chain reaction (qRT-PCR). Cell proliferation was detected by the Cell Counting Kit (CCK8). Cell cycle and apoptosis of OA chondrocytes were measured by flow cytometry. qRT-PCR and western blot were used to detect PCNA, p50, p52, p65 mRNA and protein expression levels. RESULTS: CircVCAN was highly expressed in OA tissues and OA chondrocytes. Cell proliferation and PCNA expression levels decreased significantly after transfection with si-CircVCAN in OA-chondrocytes. However, there was a significant increase on OA chondrocytes after transfection with LV-CircVCAN. Compared with the si-NC group, the apoptosis rate of OA chondrocytes was significantly increased after transfection with si-CircVCAN. The proportion of G0/G1 phase in the cell cycle was significantly reduced and the proportion of S phase was significantly increased. On the contrary, the apoptosis rate was significantly reduced after transfection with LV-CircVCAN. The proportion of G0/G1 phase in the cell cycle was significantly increased and the proportion of S phase was significantly reduced. The mRNA and protein levels of p50, p52 and p65 were significantly increased after transfection of LV-CircVCAN in OA-chondrocytes. Furthermore, PDTC (NF-κB inhibitor) transfection can significantly reverse the effect of overexpression of CircVCAN on the proliferation and apoptosis of OA chondrocytes. CONCLUSIONS: CircVCAN is overexpressed in OA tissues and cells. CircVCAN can affect the proliferation and apoptosis of OA chondrocytes by blocking the activation of the NF-κB signaling pathway. Thus, CircVCAN may be an important target molecule for OA treatment.

Effective interaction of nonuniformly charged colloid spheres in a bulk electrolyte.

The interaction energy between two like-charged colloid spheres with nonuniformly distributed surface charges immersed in a bulk electrolyte is calculated under the linearized Poisson-Boltzmann equation. The calculated results are sensitive to the relative orientations of the spheres due to the anisotropy of the distribution of charges on the sphere surface. The effective repulsive interaction after thermal average is weaker than the case when charges are uniformly distributed on the spheres, and with the increase of the nonuniformity, an attractive interaction between the two spheres emerges.

Polynomial scheme for time evolution of open and closed quantum systems.

Based on the generating function of Laguerre polynomials, we propose a Laguerre polynomial expansion scheme in the calculation of the evolution of the time-dependent Schrödinger equation. Theoretical analysis and numerical tests show that the method is equally as good as the Chebyshev polynomial expansion method in efficiency and accuracy, with the additional merits that no scaling to the Hamiltonian is needed and it has wider suitability.

Reentrant wetting transition on surfactant solution surfaces.

The wetting of polydimethylsiloxane oil drops on the surfaces of anionic surfactant sodium dodecylsulfate solutions is studied systematically by changing the bulk surfactant concentration. The wetting state changes from complete wetting to pseudopartial wetting at 0.3 cmc (critical micelle concentration) surfactant concentration and there is a reentrant transition back to complete wetting at 1.4 cmc. The measured free energy is consistent with the prediction of the wetting theory. The interaction potential minimum of the two surfaces of the oil film disappears at the reentrant point, which is speculated to be an effect of micelle formation in the solution.

Depletion interactions between two spherocylinders.

The depletion interactions between two spherocylinders as functions of their separation and their relative orientation, induced by a small hard-sphere fluid, are calculated by Monte Carlo simulations using the acceptance ratio method (ARM). The torque on the spherocylinders is determined from the resulting potential. The calculation shows that the ARM is an effective way to obtain depletion interactions of spherocylinders. The depletion interaction under the Asakura-Oosawa (also excluded-volume) approximation is also calculated numerically.

The density distributions of the counterions and the coions confined in two similarly charged plates.

By using the field-theoretic method, we established a unified systematic formulation of a model of counterions and coions confined in two similarly charged plates, and calculated the density distributions of counterions and coions with various coupling parameters by the two methods: Poisson-Boltzmann (PB) approach and the strong coupling (SC) theory, respectively. We also performed Monte Carlo simulations, and obtained the density distributions of counterions and coions with several different coupling parameters. Comparing our theoretical results with those from Monte Carlo simulation, we find that the PB approach is valid when the coupling parameter Xi is smaller than 1, but, as Xi > or = 1, the results by the PB approach deviate from the corresponding Monte Carlo simulation data, and the deviation gets larger with the coupling parameter increasing. This shows that the PB approach is completely invalid when the coupling parameter is equal to 1 or larger than 1. For the latter case, the development trend of the distribution curve calculated by SC theory agrees with that from Monte Carlo simulation as the coupling parameter increases. This demonstrates that the SC theory can give a qualitative available explanation on the density distribution of the counterions in the system in which the coupling parameters are strictly confined.

Entropic interactions on a colloidal sphere near the edge of a terrace.

We calculated the entropic interactions between a colloidal sphere and the hard edge of a terrace by means of Monte Carlo simulation with the acceptance ratio method. Comparison with the Asakura-Oosawa approximation indicates that the AO approximation is more accurate in this model than other known models. Our simulation results are also in qualitative agreement with the experimental results obtained by A.D. Dinsmore et al.

Depletion potential near curved surfaces.

We examine the depletion potential and force of a hard-sphere fluid on a single big hard sphere, located inside or outside of a hard spherical cavity, by Monte Carlo simulations to the hard-sphere fluid. The depletion potential is determined by the acceptance ratio method, while the force on the big sphere is obtained by two methods: numerical differentiation of the depletion potential and integration of the contact density of the fluid at the surface of the big sphere. The results are in excellent agreement with those obtained by density functional theory presented by Roth et al.

Spectrophotometric determination of nickel with p-acetylarsenazo.

A spectrophotometric method for the determination of trace amounts of nickel is described. At pH 6, nickel reacts with p-acetylarsenazo to form a 1:2 coloured complex with an absorption maximum at 630 nm. The apparent molar absorptivity is 6.5 x 10(4) l.mol(-1) . cm(-1) . Beer's law is obeyed over the concentration range of 0-0.8 microg/ml. The proposed method is selective, sensitive and can be applied to the determination of nickel in aluminum alloy.