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South Korea deployed the Terminal High Altitude Area Defense (THAAD) antimissile system in response to North Korea's nuclear test, leading to the Chinese government's opposition to THAAD, citing national security concerns. Chinese consumers held a large-scale "boycott for Korean products" campaign in 2014. In the same year, the China–South Korea free trade agreement (FTA) was signed. This study compares the double-difference (DID) and triple-difference (DDD) models using the impact of the THAAD political conflict on South Korean exports. In the DID model, THAAD reduced South Korean exports, while in the DDD model, the FTA effectively alleviated the impact of THAAD. The net difference of the FTA's impact on the commodities boycotted in response to the THAAD conflict exists because some boycotted commodities were promoted by the FTA while others were not. The effect of the THAAD event shock was significant only in the first two years, with minimal subsequent changes in growth. THAAD and FTA's dynamic effects provide evidence of how political conflict can eventually influence popular opinion and how the trade policy plays a significant role in the national conflict resolution. Finally, the study provides additional evidence on the effect of non-tariff barriers triggered by THAAD on the service industry. [ABSTRACT FROM AUTHOR]

Background: Programmed death-ligand 1 (PD-L1) is a negative costimulatory molecule, and its main function is widely considered to be in the regulation of T cells. Tumor-associated macrophages (TAMs) are an important part of the tumor microenvironment, and they also play an important role in immunosuppression. However, the relationship between the expression of PD-L1 and TAMs in cervical carcinoma (CC) remains unclear. We detected the expression of PD-L1 and TAMs in tumor tissue to study the correlation between them. Methods: Immunohistochemical staining of PD-L1, CD68 (pan-macrophage), and CD163 (M2-like macrophage) was performed in 120 cases of cervical squamous cell carcinoma. Logistic regression analysis was used to evaluate the predictors related to positive PD-L1 expression. We also apply the Kaplan–Meier method to study the recurrence-free and overall survival rate of CC patients. Results: The increase in PD-L1 expression in tumor cells (TC) was significantly correlated with the increase in CD163 density (r=0.8550, p< 0.0001), while PD-L1 in the stroma was also significantly associated with the intratumoral density of CD68- or CD163-positive cells (CD68 p< 0.0001; CD163 p=0.0009). The mean infiltration rates of CD68- and CD163-positive cells in PD-L1-positive TC were significantly higher than in PD-L1-negative TC (CD68 p=0.0095; CD163 p< 0.0001). In multivariate logistic regression analyses, only the density of CD163-positive cells was correlated with the expression of PD-L1 in TC cells (OR 1.52; p=0.032). In prognostic analysis, PD-L1 more than 10% was significantly correlated with short RFS (HR=2.66; p=0.028). For CD163+ macrophage evaluation, the density above the median was also significantly correlated with RFS (HR=2.48; p=0.021). Conclusion: CD163+ M2-like macrophage infiltration is highly associated with PD-L1 expression in CC, suggesting that macrophage infiltration can serve as a potential therapeutic target. [ABSTRACT FROM AUTHOR]

Abstract: Host plants will affect the performance and population dynamics of the polyphagous insect pest Grapholitha molesta (Busck) (Lepidoptera: Tortricidae). Cultivar‐level variability needs to be considered in assessing the performance of G. molesta. We evaluated the fitness of G. molesta on five apple varieties in the laboratory by placing eggs on apples and observing their performance including survival, development, and fecundity of the adult insect. Our results demonstrated differences between indices such as larval duration, pupal weight, egg production, length of tunnel, and exiting rate of larvae, which gave similar host rankings. Variety Danxia was less suitable than Jinqing and Shuohong, and more suitable than Empire and Jinxing. However, other indices such as pupal duration, total pre‐oviposition time, and the estimated population parameters resulted in a different host ranking. We calculated weighted fitness scores to overcome the problem of inconsistent rankings. Empire changed from being the second highest ranking variety based on all population parameters to the second lowest using weighted fitness scores. The difference in ranking observed between apple varieties demonstrates the care needed in predicting population performance in the field using single traits. [ABSTRACT FROM AUTHOR]

Background: Programmed death-ligand 1 (PD-L1) is a negative costimulatory molecule, and its main function is widely considered to be in the regulation of T cells. Tumor-associated macrophages (TAMs) are an important part of the tumor microenvironment, and they also play an important role in immunosuppression. However, the relationship between the expression of PD-L1 and TAMs in cervical carcinoma (CC) remains unclear. We detected the expression of PD-L1 and TAMs in tumor tissue to study the correlation between them., Methods: Immunohistochemical staining of PD-L1, CD68 (pan-macrophage), and CD163 (M2-like macrophage) was performed in 120 cases of cervical squamous cell carcinoma. Logistic regression analysis was used to evaluate the predictors related to positive PD-L1 expression. We also apply the Kaplan-Meier method to study the recurrence-free and overall survival rate of CC patients., Results: The increase in PD-L1 expression in tumor cells (TC) was significantly correlated with the increase in CD163 density ( r =0.8550, p <0.0001), while PD-L1 in the stroma was also significantly associated with the intratumoral density of CD68- or CD163-positive cells (CD68 p <0.0001; CD163 p =0.0009). The mean infiltration rates of CD68- and CD163-positive cells in PD-L1-positive TC were significantly higher than in PD-L1-negative TC (CD68 p=0.0095; CD163 p <0.0001). In multivariate logistic regression analyses, only the density of CD163-positive cells was correlated with the expression of PD-L1 in TC cells (OR 1.52; p =0.032). In prognostic analysis, PD-L1 more than 10% was significantly correlated with short RFS (HR=2.66; p =0.028). For CD163 + macrophage evaluation, the density above the median was also significantly correlated with RFS (HR=2.48; p =0.021)., Conclusion: CD163 + M2-like macrophage infiltration is highly associated with PD-L1 expression in CC, suggesting that macrophage infiltration can serve as a potential therapeutic target., Competing Interests: The authors report no conflicts of interest in this work., (© 2020 Guo et al.)

Increasing evidence indicates that disruption of normal iron homeostasis may contribute to pathological development of Alzheimer's disease. Icariin, astragalus, and puerarin have been shown to suppress iron overload in the cerebral cortex and improve spatial learning and memory disorders in Alzheimer's disease mice, although the underlying mechanism remains unclear. In the present study, APPswe/PS1ΔE9 transgenic mice were administered icariin, astragalus, and puerarin (120, 80, and 80 mg/kg, respectively, once a day, for 3 months). Iron levels were detected by flame atomic absorption spectroscopy. Interleukin-1β, interleukin-6, and tumor necrosis factor-α levels were measured in the cerebral cortex by enzyme linked immunosorbent assay. Glutathione peroxidase and superoxide dismutase activity and malondialdehyde content were determined by colorimetry. Our results demonstrate that after treatment, iron levels and malondialdehyde content are decreased, while glutathione peroxidase and superoxide dismutase activities are increased. Further, interleukin-1β, interleukin-6, and tumor necrosis factor-α levels were reduced. These results confirm that compounds of icariin, astragalus, and puerarin may alleviate iron overload by reducing oxidative stress and the inflammatory response., Competing Interests: None declared

Abnormally increased levels of iron in the brain trigger cascade amplification in Alzheimer's disease patients, resulting in neuronal death. This study investigated whether components extracted from the Chinese herbs epimedium herb, milkvetch root and kudzuvine root could relieve the abnormal expression of iron metabolism-related protein in Alzheimer's disease patients. An APPswe /PS1ΔE9 double transgenic mouse model of Alzheimer's disease was used. The intragastric administration of compounds from epimedium herb, milkvetch root and kudzuvine root improved pathological alterations such as neuronal edema, increased the number of neurons, downregulated divalent metal transporter 1 expression, upregulated ferroportin 1 expression, and inhibited iron overload in the cerebral cortex of mice with Alzheimer's disease. These compounds reduced iron overload-induced impairment of the central nervous system, indicating a new strategy for developing novel drugs for the treatment of Alzheimer's disease.

Objective: To observe the effect of intracerebroventricular injection of rAAV-HIF-1α on hippocampal neuronal apoptosis in a rat model of Alzheimer disease (AD)., Methods: Thirty-two male SD rats (250-300 g) were randomized into 4 groups (n=8), including the normal control group without any treatment, AD model group with right intracerebroventricular injection of 2 µl Aβ25-35 (10 mg/m1), sham-operated group with right intracerebroventricular injection of 2 µl normal saline, and AD+ rAAV-HIF-1α group with right intracerebroventricular injection of 10 µl rAAV-HIF-1a (1×10¹² v.g./m1) one week after Aβ25-35 injection. The rats were sacrificed to detect the expression of HIF-1α and apoptosis of hippocampal neurons 5 weeks after Aβ25-35 or saline injection., Results: Western blotting showed that the expression of HIF-1α was significantly higher in AD+rAAV-HIF-1α group (451.59±34.39) than in normal control group (229.05±41.28) and sham-operated group (216.29±37.08) (P<0.05) without significant difference between the latter two groups. The apoptotic ratio of the hippocampal neurons was significantly higher in AD model group ([19.49±2.59]%) than in normal control group ([5.41±0.75]%) and sham-operated group ([5.28±0.66]%) in (P<0.05), and intracerebroventricular injection of rAAV-HIF-1α resulted in a significant reduction of the apoptotic ratio in the AD rats ([12.07±2.06]%) (P<0.05)., Conclusion: Intracerebroventricular injection of rAAV-HIF-1α can inhibit hippocampal neuronal apoptosis in the rat model of AD.