Search

Acute liver injury (ALI) is a common life-threatening condition with a high mortality rate due to liver disease-related death. However, current therapeutic interventions for ALI remain ineffective, and the development of effective novel therapies is urgently needed. Liver samples from patients with drug-induced ALI were collected to detect adenosine kinase (ADK) expression. Male C57BL/6 J mice, hepatocyte-specific ADK knockout (ADKHKO) mice, and their controls (ADKf/f) were exposed to acetaminophen (APAP) and other treatments to investigate the mechanisms of APAP-related ALI. ADK expression was significantly decreased in APAP-injured livers. Hepatocyte-specific ADK deficiency exacerbated APAP-induced ALI, while a gain-of-function approach delivering AAV-ADK, markedly alleviated APAP-induced ALI, as indicated by changes in alanine aminotransferases (ALT) levels, aspartate aminotransferase (AST) levels, neutrophil infiltration and hepatocyte death. This study showed that ADK played a critical role in ALI by activating autophagy through two signaling pathways, the adenosine monophosphate-activated protein kinase (AMPK)-mTOR pathway and the adenosine receptor A1 (ADORA1)-Akt-mTOR pathway. Furthermore, we found that metformin upregulated ADK expression in hepatocytes and protected against APAP-induced ALI. These results demonstrate that ADK is critical in protecting against APAP-induced ALI and that developing therapeutics targeting ADK-adenosine-ADORA1 is a new approach for ALI treatment. Metformin is a potential candidate for preventing ALI by upregulating ADK. [ABSTRACT FROM AUTHOR]

Few studies have assessed sex differences in the management of suspected acute coronary syndrome (ACS). We aimed to compare the evaluation, treatment, and outcomes between males and females with suspected ACS in the emergency department. Data were obtained from a prospective registry of acute chest pain involving 21 emergency departments in Shandong Province, China. The primary endpoint was 30-day major adverse cardiac events (MACEs). Overlap propensity score weighting was used to address potential confounding. A total of 8046 patients were analysed (42.8% female). Overlap-weighted analysis showed no significant association of female sex with 30-day MACEs (odds ratio, 0.91; 95% CI 0.75 to 1.11; P = 0.363). Secondary analyses found that women were less likely to be identified as high risk at first presentation (odds ratio, 0.86; 95% CI 0.78 to 0.94; P < 0.001). In the emergency department, women were less likely to undergo antiplatelet therapy (odds ratio, 0.87; 95% CI 0.79 to 0.96; P = 0.004) or coronary angiography (odds ratio, 0.78; 95% CI, 0.69 to 0.88; P < 0.001). Women had a longer length of stay in the emergency department and were less likely to be admitted to a ward at disposition. These sex differences existed only in the non-ST-elevation subgroup and were independent of risk stratification. Women with non-ST-elevation chest pain in China received suboptimal treatment in the emergency department. However, their clinical outcomes were not significantly different from those of men. Further studies are needed to determine the causes and impacts of these sex differences. [ABSTRACT FROM AUTHOR]

Objectives: Patients with maintenance hemodialysis (MHD) experience stigma due to their dependence on machines and changes in appearance, which contributes to negative psychological outcomes. This study investigated the effect of perceived stigma on depressive symptoms and demoralization in MHD patients and explored the mediating roles of self-warmth and self-coldness. Methods: This study included 301 MHD patients in a cross-sectional design. The participants completed self-reported measures of perceived stigma, self-warmth, self-coldness, depressive symptoms, and demoralization. Structural equation modeling was used to test the relationships among the main variables. Results: The results suggested that perceived stigma was directly and positively correlated with depressive symptoms and demoralization. Both relationships were mediated by self-warmth and self-coldness. Additionally, the mediating effect of self-coldness was significantly greater than self-warmth in both the depressive symptoms and demoralization models. Conclusions: Perceived stigma was a risk factor for depressive symptoms and demoralization in MHD patients. Self-coldness played a more important mediating role than self-warmth in the relationship between perceived stigma and two negative psychological outcomes. [ABSTRACT FROM AUTHOR]

Objectives: Attachment style, as a stable personal trait, may influence posttraumatic growth (PTG) in patients with maintenance hemodialysis (MHD). Therefore, further exploration of the mediating factors that can intervene between these two variables to improve mental health is of great clinical significance. The current study aimed to examine the parallel mediating roles of self-warmth and self-coldness between attachment style and PTG among MHD patients. Methods: A total of 301 MHD patients were required to complete self-reported measures of attachment style, self-warmth, self-coldness, and PTG. Structural equation modeling (SEM) using Amos (version 23.0) was conducted to test the mediating effect. Results: The results showed that neither attachment anxiety (β = − 0.118, 95%CI [− 0.385, 0.143]) nor attachment avoidance (β = − 0.121, 95%CI [− 0.307, 0.072]) had a significant direct effect on PTG. However, attachment anxiety had a significant indirect effect on PTG through self-warmth (β = − 0.105, 95%CI [− 0.206, − 0.011]). In contrast, the indirect effect of attachment avoidance on PTG was not significant through either self-warmth (β = − 0.075, 95%CI [− 0.175, 0.026]) or self-coldness (β = − 0.005, 95%CI [− 0.049, 0.010]). Conclusions: The significant indirect effect of attachment anxiety on PTG occurred through self-warmth rather than self-coldness, which further demonstrated the necessity of distinguishing between the positive and negative components of self-compassion. More research is needed in the future to explore the different mediating mechanisms of self-warmth and self-coldness and their different roles in leading to psychological outcomes. [ABSTRACT FROM AUTHOR]

In the past two decades, the supratidal wetland in the Yellow River Delta experienced severe saline-alkalization and vegetation degradation. Restoration with enclosure-freshwater release mode has prevailed since 2002. This method presented some positive effects, but need a massive freshwater supply. Furthermore, the subsequent formed single Phragmites australis vegetation weakened the bird habitation function. In this study, we developed another restoration mode based on microtopography modification. The core idea of the mode is to enhance micro-habitat heterogeneity thus improve the water resource temporal-spatial distribution and shape more niches. An ecological restoration program was designed and implemented since May, 2015. The monitoring data from July, 2015 to December 2017 showed that, with no extra artificially drained freshwater released, the soil salinity decreased by 15.4% to 30.8%. The area of bare land decreased while that vegetation and water surface increased, resulting in relative even land cover composition, habitat heterogeneity increased and thus the bird biodiversity improved. This mode is more ecological and water cost-effective and is suitable to restore the degraded saline-alkalized supratidal wetlands. However, long-term comprehensive monitoring is essential to evaluate the restoration effect. Many detailed parameters for topography modification need further optimized. [ABSTRACT FROM AUTHOR]

Soil salinity and waterlogging are two major environmental problems in estuarine wetlands. To prevent the typical wetland plants from degradation by soil salinization and salt waterlogging and more effectively use the plants to provide wetland ecosystem services, we examined the ecological adaptability of Phragmites australis, a characteristic plant species in the Yellow River Delta, to the interactive effects of water level and salt stress. The results showed that P. australis adapts to salt and water table stressed environments through slowing down the growth rate, maintaining the tiller number, and adjusting the biomass allocation of different organs. The highest plant height and the largest leaf area were at 0 cm water table treatment; the 0.5 % NaCl treatment increased the aboveground biomass; higher water table increased the fibrous root biomass allocation, but largely decreased the leaf biomass. The exclusion of toxic inorganic ions such as Na and Cl and the accumulation of organic solutes are also important mechanisms to aid survival in saline wetlands. On average 35.1 % of Cl and 53.9 % of Na accumulated in belowground organs. The study could provide fundamental guidance for wetland restoration projects and wetland sustainable use in coastal zones such as the Yellow River Delta. [ABSTRACT FROM AUTHOR]

Stromal cell-derived factor 1 (SDF-1) and its receptor, CXCR4, play an important role in tumor progression. Epithelial-mesenchymal transition (EMT) process is linked to disease pathophysiology. This study aimed to investigate the roles and underlying mechanisms of SDF-1/CXCR4 axis in EMT process of glioblastoma. In the present study, CXCR4 activation and inhibition in U87 were induced with exogenous SDF-1 and with CXCR4 small interfering RNA (siRNA), respectively. CXCR4 downstream signal molecules AKT, ERK, and EMT biomarkers (vementin, snail, N-cadherin, and E-cadherin) were tested using the Western blot. Our results showed that SDF-1 can induce AKT and ERK phosphorylation in a dose-dependent manner, and endogenous CXCR4 can be blocked thoroughly by CXCR4 siRNA in U87. Notably SDF-1 alone treatment can induce the upregulation of vementin, snail, and N-cadherin of U87; besides, the downregulation of E-cadherin also occurred. On the contrary, CXCR4 siRNA significantly prohibited SDF-1-induced AKT and ERK phosphorylation, at the same time, EMT biomarker changes were not observed. Function analysis revealed that CXCR4 siRNA obviously interfered with U87 cell migration and proliferation, according to wound healing assay. In conclusion, this study suggested that EMT process can be triggered by the SDF-1/CXCR4 axis in glioblastoma, and then involved in the tumor cell invasion and proliferation via activation of PI3K/AKT and ERK pathway. Our study lays a new foundation for the treatment of glioblastoma through antagonizing CXCR4. [ABSTRACT FROM AUTHOR]

In coastal area, salinization is a common and serious problem for crop cultivation and ecological restoration of degraded wetlands. Therefore, the soil salinity has attracted increasing attention from farmers, government and environmental scientists. The factors controlling the soil salinity distribution have become a hot point in saline soil studies. In this study, statistics and geostatistics were used to explore the distribution of soil salinity in the Yellow River Delta (YRD) based on 150 soil samples that were collected in June 2010. Besides the experimental work, a geographical information system technique was adopted in this study. The results showed that the soil salinity ranged from 0.11 to 10.50 dS m and the salinity in topsoil was higher than that in subsoil in the YRD, indicating that the salt in subsoil moved up and accumulated in topsoil as a function of evaporation. There was a significant difference among soil salinity spatial variances from different soil depths in the YRD. Generally, soil salinity of the topsoil was higher than that of the subsoil. Meanwhile, there were significant positive correlations in soil salinity between different soil depths. In addition, landforms, land uses, soil types and soil texture were important factors affecting soil salinity. The current distribution of soil salinity resulted from the comprehensive effects of anthropogenic activities and natural processes. The present study results suggest that the impacts of human activities were critical factors for salt redistribution in the coastal wetlands, which should be valuable for agricultural management and ecological restoration in the YRD. [ABSTRACT FROM AUTHOR]

Using the Eddy Covariance (EC) technique, we analyzed temporal variation in net ecosystem CO exchange (NEE) and determined the effects of environmental factors on the balance between ecosystem photosynthesis and respiration in a reed ( Phragmites australis) wetland in the Yellow River Delta, China. Our results indicated that diurnal and seasonal patterns of NEE and its components (ecosystem respiration ( R), gross primary production (GPP)) varied markedly among months for the growing season (May to October). The cumulative CO emission was 1,657 g CO m, while 2,612 g CO m was approximately accumulated as GPP, which resulted in the reed wetland being a net sink of 956 g CO m. The ratio of R to GPP in reed wetland was 0.68, which was close to other temperate wetlands. Soil temperature and soil moisture exerted the primary controls on R during the growing season. Daytime NEE values during the growing season were strongly correlated with photosynthetically active radiation. Aboveground biomass showed significant linear relationships with 24-h average NEE, daytime GPP, and R, respectively. Thus, we conclude that the coastal wetland acted as a carbon sink during the growing season despite the variations in environmental conditions, and long-term flux measurements over these ecosystems are undoubtedly necessary. [ABSTRACT FROM AUTHOR]

Vegetation type and density exhibited a considerable patchy distribution at very local scales in the Yellow River Delta, due to the spatial variation of soil salinity and water scarcity. We proposed that soil respiration is affected by the spatial variations in vegetation type and soil chemical properties and tested this hypothesis in three different vegetation patches ( Phragmites australis, Suaeda heteroptera and bare soil) in winter (from November 2010 to April 2011). At diurnal scale, soil respiration all displayed single-peak curves and asymmetric patterns in the three vegetation patches; At seasonal scale, soil respiration all declined steadily until February, and then increased to a peak in next April. But, the magnitude of soil respiration showed significant differences among the three sites. Mean soil respiration rates in winter were 0.60, 0.45 and 0.17 μmol CO m s for the Phragmites australis, Suaeda heteroptera and bare soil, respectively. The combined effect of soil temperature and soil moisture accounted for 58-68 % of the seasonal variation of winter soil respiration. The mean soil respiration revealed positive and linear correlations with total N, total N and SOC storages at 0-20 cm depth, and plant biomass among the three sites. We conclude that the patchy distribution of plant biomass and soil chemical properties (total C, total N and SOC) may affect decomposition rate of soil organic matter in winter, thereby leading to spatial variations in soil respiration. [ABSTRACT FROM AUTHOR]

The delivery and distribution of nutrients in coastal wetland ecosystems is much related to the land use. The spatial variations of TOC, TN, NH4+-N, NO3−-N and TP and associated soil salinity with depth in 9 kinds land uses in coastal zone of the modern Yellow River Delta (YRD) was evaluated based on monitoring data in field from 2009 to 2015. The results showed that the average contents of soil TOC, TN, NO3−-N, NH4+-N and TP were 4.21 ± 2.40 g kg−1, 375.91 ± 213.44, 5.36 ± 9.59 and 7.20 ± 5.58 and 591.27 ± 91.16 mg kg−1, respectively. The high N and C contents were found in cropland in southern part and low values in natural wetland, while TP was relatively stable both in profiles and in different land uses. The land use, land formation age and salinity were important factors influencing distributions of TOC and N. Higher contents of TOC and N were observed in older formation age lands in whole study region, while the opposite regulation were found in new-born natural wetland, indicating that the anthropogenic activities could greatly alter the original distribution regulations of nutrients in coastal natural wetlands by changing the regional land use. [ABSTRACT FROM AUTHOR]

Coastal ecosystems play significant ecological and economic roles but are threatened and facing decline. Microbes drive various biogeochemical processes in coastal ecosystems. Tidal flats are critical components of coastal ecosystems; however, the structure and function of microbial communities in tidal flats are poorly understood. Here we investigated the seasonal variations of bacterial communities along a tidal flat series (subtidal, intertidal and supratidal flats) and the factors affecting the variations. Bacterial community composition and diversity were analyzed over four seasons by 16S rRNA genes using the Ion Torrent PGM platform. Bacterial community composition differed significantly along the tidal flat series. Bacterial phylogenetic diversity increased while phylogenetic turnover decreased from subtidal to supratidal flats. Moreover, the bacterial community structure differed seasonally. Canonical correspondence analysis identified salinity as a major environmental factor structuring the microbial community in the sediment along the successional series. Meanwhile, temperature and nitrite concentration were major drivers of seasonal microbial changes. Despite major compositional shifts, nitrogen, methane and energy metabolisms predicted by PICRUSt were inhibited in the winter. Taken together, this study indicates that bacterial community structure changed along the successional tidal flat series and provides new insights on the characteristics of bacterial communities in coastal ecosystems. [ABSTRACT FROM AUTHOR]