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Losartan has become a hot spot in the treatment of non-alcoholic fatty liver disease (NAFLD) among angiotensin receptor blocker drugs. We sought to conduct a systematic examination and meta-analysis to examine the effects of losartan on patients with NAFLD. We searched for potentially randomized controlled trials in PubMed, Embase, China National Knowledge Infrastructure, Wanfang, and the Cochrane database up to October 09, 2022. We used the Cochrane risk of bias tool to evaluate the study quality. Analysis of subgroups, sensitivity analysis, and publishing bias were explored. The quality of the included studies was moderate to high. Six trials involving 408 patients were included. The meta-analysis demonstrated that aspartate transaminase was significantly affected by losartan therapy (mean difference [MD] = −5.34, 95% confidence interval [CI] [−6.54, −4.13], Z = 8.70, P < 0.01). The meta-analysis subgroup showed that losartan 50 mg once daily could lower the level of alanine aminotransferase (MD = −18.92, 95% CI [−21.18, −16.66], Z = 16.41, P < 0.01). There was no statistically significant difference in serum total cholesterol, triglyceride, low-density lipoprotein, and high-density lipoprotein.

Climate warming, rising atmospheric CO2 concentration (C a), and nitrogen (N) availability are exerting profound impacts on global forest ecosystems, particularly in high-altitude mountains. This study investigated the tree-growth dynamics of timberline Larix chinensis in the Taibai Mountain, central China, and explored its ecophysiological responses to environmental stresses by combining tree growth and stable isotopes. The results showed that the growth rate of L. chinensis has significantly increased since the 1960s, and that tree growth in this timberline was particularly sensitive to temperature in spring. Moreover, the continuously rising intrinsic water-use efficiency (iWUE), linked to higher C a and warmer environment, promoted the growth of L. chinensis. Before the 1960s, tree-ring δ15N gradually increased, then shifted to an insignificant decline with the acceleration of tree growth, and broke the preexisting carbon–nitrogen balance. Meanwhile, climate warming and increased iWUE have replaced N as the principal drivers of tree growth since the 1960s. It is believed that L. chinensis may gradually suffer a decline in N availability as it continues to grow rapidly. The insightful understanding of the biochemical mechanisms of plant responses to growth-related environmental conditions will improve our ability to predict the evolution of high-elevation mountain ecosystems in the future. [ABSTRACT FROM AUTHOR]

Understanding the water-use strategy of human-planted species used in response to climate change is essential to optimize afforestation programs in dry regions. Since 2000, trees on the central Loess Plateau have experienced a shift from strengthening drought to weakening drought. In this study, we combined tree-ring δ13C and δ18O records from Pinus tabuliformis (syn. tabulaeformis) Carr. (a tree) and Sophora viciifolia Hance (a shrub) on the central Loess Plateau to investigate species-specific responses to rising atmospheric CO2 (Ca) and drought. We found summer relative humidity controlled the fractionation of tree-ring δ18O, but the magnitude of the climate influence on δ13C differed between the species. The intrinsic water-use efficiency (iWUE) trends of both species suggested a strongly active response to maintain constant intercellular CO2 concentrations as Ca rose. The tree-ring δ13C and δ18O of both species using first-difference data were significantly and positively correlated, with stronger relationships for the shrub. This indicated the dominant regulation of iWUE by stomatal conductance in both species, but with greater stomatal control for the shrub. Moreover, the higher mean iWUE value of S. viciifolia indicated a more conservative water-use strategy than P. tabuliformis. Based on our commonality analysis, the main driver of the increased iWUE was the joint effect of Ca and vapor-pressure deficit (25.51%) for the tree, while it was the joint effect of Ca and the self-calibrated Palmer drought severity index (39.13%) for the shrub. These results suggest S. viciifolia will be more drought-tolerant than P. tabuliformis and as Ca continually rises, we should focus more on the effects of soil drought than atmospheric drought on the water-use strategy of S. viciifolia. [ABSTRACT FROM AUTHOR]

Purpose. Immunotherapy provides a new treatment option for advanced gastric cancer (AGC). This study aims to explore the response markers of immunotherapy in AGCs. Methods. Next-generation sequencing was performed on 44 AGC patients who received immune checkpoint inhibitors and the associations between their outcomes after combination immunotherapy, and the clinicopathological/molecular characteristics were analyzed. Results. The current study cohort had a median progression-free survival (PFS) of 5.9 months, an overall survival (OS) of 12.1 months, and an objective response rate (ORR) of 36.4%. Through multivariable analysis of the clinical characteristics, primary tumor resection (HR = 2.66, 95% CI: 1.06–6.70, p = 0.037) and increased proportion of lymphocytes after combination immunotherapy (HR = 0.40, 95% CI: 0.16–0.99, p = 0.048) were revealed as independent predictors for patient outcomes. All the 18 patients who underwent genetic profiling were microsatellite-stable with a median TMB of four mutations per Mb. ATM alterations, PI3K pathway mutations, increased TMB, and positive PD-L1 expression were associated with the increased trend of PFS and ORR. According to the combination of baseline lymphocyte count, ATM mutation, TMB status, and PD-L1 expression, patients were stratified into higher- and lower-risk groups, with the lower-risk group showing improved PFS (HR = 4.7e−10, 95% CI: 0–inf, p = 0.02) and ORR (75% vs. 0%, p = 0.007). Conclusion. Several highly relevant potential biomarkers predictive of immunotherapy response in AGC patients have been identified in this research. [ABSTRACT FROM AUTHOR]

Particulate matter contributes much to the haze pollution in China. Meteorological conditions and environmental management significantly influenced the accumulation, deposition, transportation, diffusion, and emission intensity of particulate matter. In this study, temporal and spatial variations of PM10 and PM2.5—and the responses to meteorological factors and environmental regulation intensity—were explored in Xi'an, China. The concentrations of PM10 were higher than those of PM2.5, especially in spring and winter. The mean annual concentrations of PM10 and PM2.5 markedly decreased from 2013 to 2017, but the decreasing trend has plateaued since 2015. The concentrations of PM10 and PM2.5 exhibited seasonal differences, with winter being the highest and summer the lowest. Air quality monitoring stations did not reveal significant spatial variability in PM10 and PM2.5 concentrations. The concentrations of PM10 and PM2.5 were significantly influenced by precipitation, relative humidity, and atmospheric temperature. The impact of wind speed was prominent in autumn and winter, while in spring and summer the impact of wind direction was obvious. Additionally, the emission intensity of SO2, smoke and dust could be effectively decreased with the increasing environmental regulation intensity, but not the concentrations of particulate matter. This study could provide a scientific framework for atmospheric pollution management. [ABSTRACT FROM AUTHOR]

Flash drought is an extreme phenomenon, characterized by unusually rapid intensification of drought severity, with strong impacts on plant growth especially for crops. However, it's unclear how hydrometeorological changes contribute to flash drought and how vegetation physiology, greenness, and productivity respond to flash drought. In this study, we developed an multivariate integrated framework for flash drought identification using a regression model based on principal-components analysis (PCA): the PCA regression flash drought (PRFD) model. Three criteria are specified to emphasize the rapid intensification of drought and its impacts on vegetation growth and water resources. We applied our new model in two geographical units with different climates and hydrology: one is dominated by agriculture and subject to natural drought (the Loess Plateau) and the other, a natural region with infrequent drought (the Qinling Mountains). We found that high frequency of flash droughts is most likely to occur in the eastern and central Loess Plateau and part of the Qinling Mountains. However, in relatively humid areas, flash drought shows strong intensity such as the Qinling Mountains and western and eastern edges of the Loess Plateau. Trend analysis indicates that PRFD has increased frequency, longer duration, and stronger intensity since the 1990s in both regions. From an ecological perspective, PRFD also showed a spatial pattern consistent with values of vegetation-related proxies that were below the long-term average, demonstrating vegetation transpiration, normalized-difference vegetation index (NDVI), gross primary productivity have obvious feedback on flash drought events. The Loess Plateau's NDVI responded immediately to flash drought, versus a 1-month lag in the Qinling Mountains. Because our proposed framework integrates multiple aspects of drought information, it can be applied in areas outside the study region according to regional hydrometeorological conditions. This has significant implications for improving agricultural management and forecasting future severe impacts of flash drought on plant growth. • A new integrated framework is proposed to identify flash drought (FD) events. • FD with greater frequency, longer pentads, and stronger intensity since 1990s. • Vegetation structure and physiological function respond rapidly to FD. • The response time of plant activity to FD is different in diverse climate-water regions. [ABSTRACT FROM AUTHOR]

The specific mechanism of 4-hydroxysesamin (4-HS), a modification of Sesamin, on right ventricular failure due to pulmonary hypertension (PH) is ominous. By creating a rat model of PH in vivo and a model of pulmonary artery smooth muscle cell (PASMC) hypoxia and inflammation in vitro , the current work aimed to investigate in depth the molecular mechanism of the protective effect of 4-HS. In an in vitro model of hypoxia PASMC, changes in cell proliferation and inflammatory factors were detected after treatment with 4-HS, followed by changes in the JNK/p38 MAPK signaling pathway as detected by Western blot signaling pathway. The findings demonstrated that 4-HS was able to minimize PASMC cell death, block the JNK/p38 MAPK signaling pathway, and resist the promoting effect of hypoxia on PASMC cell proliferation. Following that, we found that 4-HS could both mitigate the right ventricular damage brought on by MCT and had a protective impact on rats Monocrotaline (MCT)-induced PH in in vivo investigations. The key finding of this study is that 4-HS may protect against PH by inhibiting the JNK/p38 MAPK signaling pathway.