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In recent years, immunotherapy with immune checkpoint as the target has made revolutionary breakthroughs in the treatment of a variety of advanced solid tumors. Notwithstanding the impressive long-term therapeutic benefits, their efficacy is limited to a small subset of cancer patients. Some patients experienced drug resistance and immune-related adverse events (irAEs). Immune checkpoint inhibitors (ICIs) primarily include antibodies targeting CTLA-4 and antibodies targeting PD-1 and its ligands. Thus, it is of utmost importance to screen potential biomarkers in populations that may benefit from immunotherapy, to maximize therapeutic benefits. This review summarizes the mechanism of ICIs and its related efficacy biomarker, to better guide the application of immunotherapy in clinical practice.

In recent years, with the in-depth study of PD-1 and PD-L1 and the development of immunotherapy, the first problem is how to screen the beneficiaries. Recent clinical studies have shown that the expression level of PD-L1 in circulating tumor cells (CTC) can be used as a potential biomarker to play a guiding role in immunotherapy of malignant tumors. This article reviews the latest clinical research progress on the expression of PD-L1 in circulating tumor cells in various solid tumors.

【Background】 Leaf area index (LAI) is one of the most important plant traits. It modulates both photosynthetic rate and transpiration, and understanding its variation in response to environmental change at different growth stages is hence important to improve crop management and safeguard agricultural production. 【Objective】 The purpose of this paper is to present the results of an experimental study on the relationship between hyperspectral reflectance and LAI of peanut. 【Method】 The experiment was conducted in 2019 at Zhengzhou Agricultural Meteorological Experimental station, in which hyperspectral data of the peanut canopy at different growth stages was measured using the ASD HandHeld 2. In the meantime, we also measured LAI of the peanut using the LAI 2200 canopy analyzer. We used both the logarithm of reciprocal of the hyperspectral data and the derivatives of the hyperspectral data to estimate the LAI. Different models including models using a single parameter derived from the hyperspectral data and multiple stepwise regression models were developed to estimate the LAI. Their accuracy and reliability were compared and tested again the measured LAI. 【Result】 Exponential model using a single parameter derived from the hyperspectral data is reliable with R2 being reasonably high for most tested examples. In particular, when using the parameter VI1=Rg/Rr (where Rg and Rr are the reflectance spectra of the green and red wavelength respectively), VI2=(Rg-Rr)/(Rg+Rr), or Rr, their associated R2 was all greater than 0.68. The rooted mean of square error of VI2 was the least, followed by VI1. 【Conclusion】 Using a single parameter, exponential mode using VI2 was most accurate to estimate peanut LAI at different growth stages. Analysis revealed that the most sensitive spectral indices for estimating the LAI were VI2 and VI1, and the multiple stepwise regression models using multiple spectral parameters were more accurate than the single-parameter models but they are more computationally complicated.

Objective To explore the clinical effect of bulk-fill composite resin combined with transparent preformed crowns for aesthetic restoration of deciduous incisor of children. Methods A predesigned clinical prospective randomized controlled research method was used to select 90 patients (123 teeth). The random number table method was divided into three groups: A, B, and C. Group A was treated with a bulk-fill composite resin of SF (SonicFill) combined with a transparent preformed crown (41 teeth in 30 cases), and group B was treated with a large block of Tetric N-Ceram Bulk Fill Composite resin combined with transparent preformed crowns (39 teeth in 29 cases). Group C was treated with 3M Z350 XT universal nano resin combined with transparent preformed crowns (43 teeth in 31 cases). The visual analog scale (VAS) and the modified USPHS standard were used to evaluate the completeness, marginal steps, marginal discoloration, surface condition, secondary caries and satisfaction of the parents with prostheses after 12 months. Results Twelve months after the operation, the evaluation indexes of group A were better than those of group B and group C, and the differences were statistically significant, including edge integrity (χ2=10.847, P=0.028), edge step (χ2=7.799, P=0.020), edge discoloration (χ2=10.391, P=0.034), surface state (χ2=11.476, P=0.021), and secondary caries (χ2=10.447, P=0.034). The satisfaction of parents in group A on the overall contour (χ2=10.238, P=0.037), shape and texture (χ2=11.521, P=0.021) were better than those in group B and group C, and the differences were statistically significant. There was no significant difference in the evaluation of color satisfaction among the three groups (χ2=0.990, P=0.610). Conclusion SonicFill bulk-fill composite resin combined with transparent preformed crown is good for short-term aesthetic restoration of deciduous incisor, and parental satisfaction is high.

A method for determining the mesh stiffness of internal gears is proposed by using a combination of finite element method and the contact theory. The global deformation of contact point is separated by a full finite element model and a partial one. The local contact deformation is calculated by using the analytical formula for a line contact problem. The mesh stiffness and load distribution can be obtained after solving the nonlinear contact equilibrium equations. Compared with the conventional finite element method,the proposed method has higher computational efficiency and stability. And it also overcomes the disadvantage that the analytical method is difficult to consider helical gears and different gear ring structures. Then the influences of constraints number and thickness of ring gears on the mesh stiffness are analyzed. This method can provide effective guidance for the design of the strength and dynamic characteristics of the internal gears.