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Drained wetlands are thought to be carbon (C) source hotspots, and rewetting is advocated to restore C storage in drained wetlands for climate change mitigation. However, current assessments of wetland C balance mainly focus on vertical fluxes between the land and atmosphere, frequently neglecting lateral carbon fluxes and land‐use effects. Here, we conduct a global synthesis of 893 annual net ecosystem C balance (NECB) measures that include net ecosystem exchange of CO2, along with C input via manure fertilization, and C removal through biomass harvest or hydrological exports of dissolved organic and inorganic carbon, across wetlands of different status and land uses. We find that elevating water table substantially reduces net ecosystem C losses, with the annual NECB decreasing from 2579 (95% interval: 1976 to 3214) kg C ha−1 year−1 in drained wetlands to −422 (−658 to −176) kg C ha−1 year−1 in natural wetlands, and to −934 (−1532 to −399) kg C ha−1 year−1 in rewetted wetlands globally. Climate, land‐use history, and time since water table changes introduce variabilities, with drainage for (sub)tropical agriculture or forestry uses showing high annual C losses, while the net C losses from drained wetlands can continue to affect soil C pools for several decades. Rewetting all types of drained wetlands is needed, particularly for those formerly agriculture‐used (sub)tropical wetlands where net ecosystem C losses can be largely reduced. Our findings suggest that elevating water table is an important initiative to reduce C losses in degraded wetlands, which could contribute to policy decisions for managing wetlands to enhance their C sequestration. [ABSTRACT FROM AUTHOR]

Cucumber green mottle mosaic virus (CGMMV) belongs to the Tobamovirus genus and is an important quarantine virus of cucurbit crops. Seedborne transmission is one of the principal modes for CGMMV spread, and effective early detection is helpful to prevent the occurrence of the disease. Quantitative real-time reverse-transcription PCR (RT-qPCR) is a sensitive and rapid method for detecting CGMMV nucleic acids, but it cannot distinguish between infectious and noninfectious viruses. In the present work, a propidium monoazide (PMA) assisted RT-qPCR method (PMA-RT-qPCR) was developed to rapidly distinguish infectious and inactive CGMMV. PMA is a photoactive dye that can selectively react with viral RNA released or inside inactive CGMMV virions but not viral RNA inside active virions. The formation of PMA-RNA conjugates prevents PCR amplification, leaving only infectious virions to be amplified. The primer pair cp3-1F/cp3-1R was designed based on the coat protein (cp) gene for specific amplification of CGMMV RNA by RT-qPCR. The detection limit of the RT-qPCR assay was 1.57 × 102 copies·μL−1. PMA at 120 μmol·L−1 was suitable for the selective quantification of infectious CGMMV virions. Under optimal conditions, RT-qPCR detection of heat-inactivated CGMMV resulted in Ct value differences larger than 16 between PMA-treated and non-PMA-treated groups, while Ct differences less than 0.23 were observed in the detection of infectious CGMMV. For naturally contaminated watermelon leaf, fruit and seedlot samples, infectious CGMMV were quantified in 13 out of the 22 samples, with infestation levels of 102~105 copies·g−1. Application of this assay enabled the selective detection of infectious CGMMV and facilitated the monitoring of the viral pathogen in watermelon seeds and tissues, which could be useful for avoiding the potential risks of primary inoculum sources. [ABSTRACT FROM AUTHOR]

Background: The prognosis of hepatocellular carcinoma (HCC) is not optimistic. Our study focused on present inflammatory markers, including the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), gamma-glutamyl transpeptidase-to-platelet ratio (GPR), aspartate aminotransferase-to-lymphocyte ratio (ALR) and fibrinogen-to-albumin ratio (FAR), and explored their optimal combination for the prognosis of HCC after resection. Methods: A total of 347 HCC patients who underwent curative resection were enrolled. The optimal cutoff values of the inflammatory markers were calculated using receiver operating characteristic (ROC) curve analysis, and used to divide patients into two groups whose differences were compared by Kaplan–Meier analysis. Cox univariate and multivariate analyses were used to analyze the independent prognostic inflammatory markers. The χ2 test was chosen to determine the relationship between independent prognostic inflammatory markers and clinicopathological features. We created combined scoring models and evaluated them by Cox univariate and multivariate methods. The concordance index (C-index), Akaike information criterion (AIC) and likelihood ratio were calculated to compare the models. The selected optimal inflammatory markers and their combinations were tested in different stages of HCC by Kaplan–Meier analysis. Results: The ALR and GPR were independent prognostic factors for disease-free survival (DFS); the ALR, PLR, and GPR were independent prognostic factors for overall survival (OS). The proposed GPR and ALR-GPR-PLR score models were independent predictors for DFS and OS, respectively. Conclusion: The preoperative GPR and ALR-GPR-PLR score models were independent predictors for DFS and OS, respectively, and performed well in stratifying patients with HCC. The higher the score in the model was, the worse the prognosis. [ABSTRACT FROM AUTHOR]

Introduction: Glutamine metabolism is essential for the proliferation of cancer cells. Transported by SLC1A5, a Na+ dependent transporter, glutamine is absorbed for further use. Recent studies have revealed the anti-tumor effect of berberine. The present study aimed to evaluate the effect of berberine on cancer cell glutamine metabolism. Materials and methods: The inhibitory effect of berberine on liver cancer cells was analyzed by CCK-8 and EdU assay. The glutamine concentrations were detected by ELISA and UHPLC-MRM-MS analysis. Glutamine metabolism-related proteins were determined by Western blot, immunofluorescent analysis and immunohistochemistry. Results: Berberine inhibited the proliferation of Hep3B and BEL-7404 cell in vitro. Berberine suppressed the glutamine uptake by inhibiting SLC1A5. The upregulation of SLC1A5 led to an increased glutamine uptake and improved tolerance to berberine. Berberine suppresses SLC1A5 expression by inhibiting c-Myc. Furthermore, berberine suppresses the growth of tumor xenografts, and the expression of SLC1A5 and c-Myc in vivo. The high expression of SLC1A5 in hepatocellular carcinoma (HCC) tissues is associated with poor prognosis. Conclusion: Berberine can suppress the proliferation of liver cancer cells by reducing SLC1A5 expression. [ABSTRACT FROM AUTHOR]

Background: In vivo pig liver xenotransplantation preclinical trials appear to have poor efficiency compared to heart or kidney xenotransplantation because of xenogeneic rejection, including coagulopathy, and particularly thrombocytopenia. In contrast, ex vivo pig liver (wild type) perfusion systems have been proven to be effective in "bridging" liver failure patients until subsequent liver allotransplantation, and transgenic (human CD55/CD59) modifications have even prolonged the duration of pig liver perfusion. Despite the fact that hepatocyte cell lines have also been proposed for extracorporeal blood circulation in conditions of acute liver failure, porcine hepatocyte cell lines, and the GalT‐KO background in particular, have not been developed and applied in this field. Herein, we established immortalized wild‐type and GalT‐KO porcine hepatocyte cell lines, which can be used for artificial liver support systems, cell transplantation, and even in vitro studies of xenotransplantation. Methods: Primary hepatocytes extracted from GalT‐KO and wild‐type pigs were transfected with SV40 LT lentivirus to establish immortalized GalT‐KO porcine hepatocytes (GalT‐KO‐hep) and wild‐type porcine hepatocytes (WT). Hepatocyte biomarkers and function‐related genes were assessed by immunofluorescence, periodic acid‐Schiff staining, indocyanine green (ICG) uptake, biochemical analysis, ELISA, and RT‐PCR. Furthermore, the tumorigenicity of immortalized cells was detected. In addition, a complement‐dependent cytotoxicity (CDC) assay was performed with GalT‐KO‐hep and WT cells. Cell death and viability rates were assessed by flow cytometry and CCK‐8 assay. Results: GalT‐KO and wild‐type porcine hepatocytes were successfully immortalized and maintained the characteristics of primary porcine hepatocytes, including albumin secretion, ICG uptake, urea and glycogen production, and expression of hepatocyte marker proteins and specific metabolic enzymes. GalT‐KO‐hep and WT cells were confirmed as having no tumorigenicity. In addition, GalT‐KO‐hep cells showed less apoptosis and more viability than WT cells when exposed to complement and xenogeneic serum. Conclusions: Two types of immortalized cell lines of porcine hepatocytes with GalT‐KO and wild‐type backgrounds were successfully established. GalT‐KO‐hep cells exhibited higher viability and injury resistance against a xenogeneic immune response. [ABSTRACT FROM AUTHOR]

Determination of tipping points in nitrogen (N) isotope (δ15N) natural abundance, especially soil δ15N, with increasing aridity, is critical for estimating N‐cycling dynamics and N limitation in terrestrial ecosystems. However, whether there are linear or nonlinear responses of soil δ15N to increases in aridity and if these responses correspond well with soil N cycling remains largely unknown. In this study, we investigated soil δ15N and soil N‐cycling characteristics in both topsoil and subsoil layers along a drought gradient across a 3000‐km transect of drylands on the Qinghai–Tibetan Plateau. We found that the effect of increasing aridity on soil δ15N values shifted from negative to positive with thresholds at aridity index (AI) = 0.27 and 0.29 for the topsoil and subsoil, respectively, although soil N pools and N transformation rates linearly decreased with increasing aridity in both soil layers. Furthermore, we identified markedly different correlations between soil δ15N and soil N‐cycling traits above and below the AI thresholds (0.27 and 0.29 for topsoil and subsoil, respectively). Specifically, in wetter regions, soil δ15N positively correlated with most soil N‐cycling traits, suggesting that high soil δ15N may result from the "openness" of soil N cycling. Conversely, in drier regions, soil δ15N showed insignificant relationships with soil N‐cycling traits and correlated well with factors, such as soil‐available phosphorus and foliage δ15N, demonstrating that pathways other than typical soil N cycling may dominate soil δ15N under drier conditions. Overall, these results highlight that different ecosystem N‐cycling processes may drive soil δ15N along the aridity gradient, broadening our understanding of N cycling as indicated by soil δ15N under changing drought regimes. The aridity threshold of soil δ15N should be considered in terrestrial N‐cycling models when incorporating 15N isotope signals to predict N cycling and availability under climatic dryness. [ABSTRACT FROM AUTHOR]

Caches are vulnerable to side-channel attacks as a type of shared hardware resource. Most existing defense methods can be categorized into two categories: partition and randomization. However, cache partition will bring a large performance overhead and randomization has been proven to be not safe enough. In this paper, we propose a design called ExtendCache. Different from other defense schemes applied to the entire cache, ExtendCache focuses on cache sets that may cause information leakage, which can greatly reduce the impact on performance. Based on the fact that a conflict-based attack requires a large number of accesses to the target set, ExtendCache locates the cache set that may contain sensitive information and be stolen by the attacker according to the number of accesses. After locating a suspicious set, it extends the set by borrowing cache lines from another set. This prevents attackers from controlling the state of the target set and observing effective victim behavior. We implemented ExtendCache on gem5 and took the modular square algorithm as an example to prove the effectiveness of our design. When evaluated using the SPEC2017 benchmarks, ExtendCache had minimal impact on performance, with only a 0.48% average performance loss observed. [ABSTRACT FROM AUTHOR]

This study aimed to observe the effects of Se deficiency on epiphyseal plates of two generation DA rats fed with artificial total synthetic low Se diet. All F0 and F1 DA rats were fed with synthetic low Se diet (SeD group) and low Se diet supplied with Se (SeS group). The levels of selenium and enzyme activities of GPx were detected in plasma of the rats. General growth of bone and articular cartilage was measured macroscopically and microscopically. The epiphyseal plate of femur heads or tibia were obtained to histological and immunohistochemical examinations. The cartilage from left knee joints and femur heads was used to detect the gene expression of collagens, ADAMTSs and several selenoproteins by RT- qPCR. Two generation SeD rats showed Se insufficiency status. The thicknesses of the femur and tibial epiphyseal plates in both F0 and F1 SeD rats were significantly less than that of SeS rats. In F1 generation, SeD rats showed much fewer proliferative chondrocyte layers than SeS ones. Importantly, two generation SeD rats both showed significantly more serious pathological changes of epiphyseal plates. In two generation rats, gene expressions of COL II, GPx1 and GPx4 were significantly down-regulated in SeD rats than SeS ones; meanwhile ADAMTS-4 showed an up-regulated expression in cartilage. Dietary Se deficiency can apparently cause epiphyseal plate lesion and decrease cartilage type II collagen production and GPx1 activity in two generation DA rats fed with the artificial total synthesis low Se diet. [ABSTRACT FROM AUTHOR]

Pig liver xenotransplantation appears to be more perplexing when compared to heart or kidney xenotransplantation, even though great progress has been achieved. The relevant molecular mechanisms involved in xenogeneic rejection, including coagulopathy, and particularly thrombocytopenia, are complex, and need to be systematically investigated. The deletion of expression of Gal antigens in the liver graft highlights the injurious impact of nonGal antigens, which continue to induce humoral rejection. Innate immunity, particularly mediated by macrophages and natural killer cells, interplays with inflammation and coagulation disorders. Kupffer cells and liver sinusoidal endothelial cells (LSECs) together mediate leukocyte, erythrocyte, and platelet sequestration and phagocytosis, which can be exacerbated by increased cytokine production, cell desialylation, and interspecies incompatibilities. The coagulation cascade is activated by release of tissue factor which can be dependent or independent of the xenoreactive immune response. Depletion of endothelial anticoagulants and anti‐platelet capacity amplify coagulation activation, and interspecies incompatibilities of coagulation‐regulatory proteins facilitate dysregulation. LSECs involved in platelet phagocytosis and transcytosis, coupled with hepatocyte‐mediated degradation, are responsible for thrombocytopenia. Adaptive immunity could also be problematic in long‐term liver graft survival. Currently, relevant evidence and study results of various genetic modifications to the pig donor need to be fully determined, with the aim of identifying the ideal transgene combination for pig liver xenotransplantation. We believe that clinical trials of pig liver xenotransplantation should initially be considered as a bridge to allotransplantation. [ABSTRACT FROM AUTHOR]