Spatially Explicit Modeling of Long-Term Drought Impacts on Crop Production in Austria

Droughts have serious and widespread impacts on crop production with substantial economic losses. The frequency and severity of drought events may increase in the future due to climate change. We have developed three meteorological drought scenarios for Austria in the period 2008-2040. The scenarios are defined based on a dry day index which is combined with bootstrapping from an observed daily weather dataset of the period 1975-2007. The severity of long-term drought scenarios is characterized by lower annual and seasonal precipitation amounts as well as more significant temperature increases compared to the observations. The long-term impacts of the drought scenarios on Austrian crop production have been analyzed with the biophysical process model EPIC (Environmental Policy Integrated Climate). Our simulation outputs show that—for areas with historical mean annual precipitation sums below 850 mm— already slight increases in dryness result in significantly lower crop yields i.e. depending on the drought severity, between 0.6% and 0.9% decreases in mean annual dry matter crop yields per 1.0% decrease in mean annual precipitation sums. The EPIC results of more severe droughts show that spring and summer precipitation may become a limiting factor in crop production even in regions with historical abundant precipitation.

Imperative for long-term management and surveillance in Kawasaki disease

Kawasaki disease(KD)is a significant pediatric vasculitis known for its potential to cause severe coronary artery complications.Despite the effectiveness of initial treatments,such as intravenous immunoglobulin,KD patients can experience long-term cardiovascular issues,as evidenced by a recent case report of an adult who suffered a ST-segment elevation myocardial infarction due to previous KD in the World Journal of Clinical Cases.This editorial emphasizes the critical need for long-term management and regular surveillance to prevent such complications.By drawing on recent research and case studies,we advocate for a structured approach to follow-up care that includes routine cardiac evaluations and preventive measures.

Photosynthetic acclimation to long-term high temperature and soil drought stress in two spruce species (Picea crassifolia and P. wilsonii) used for afforestation

Picea crassifolia and P.wilsonii,commonly used for afforestation in northern China,are increasingly likely to be subjected to high temperatures and soil drought stress as a result of global warming.However,little is known about the effects of these stresses on foliar photosynthesis in the two species.To investigate how photosynthetic characteristics and sensitivity respond to prolonged high temperatures and soil drought,foliar gas exchange and other closely related parameters were recorded from four-year-old seedlings of both species.Seedlings were grown under two temperature treatments(25/15 and 35/25 °C) and four soil water regimes [80,60,40 and 20% of maximum field capacity(FC)] for 4 months.Although all treatments significantly reduced photosynthetic rates(Pn) of both species,P.crassifolia exhibited greater photosynthetic acclimation than P.wilsonii.Differences in photosynthetic acclimation were mainly related to variations in stomatal conductance(Cond) and the maximum quantum yield of PSII(Fv/Fm) between treatments.Indeed,higher Cond and Fv/Fmin all treatments were shown for P.crassifolia than for P.wilsonii.Moreover,photosynthesis in P.crassifolia exhibited inherently lower temperature sensitivities(broader span for the temperature response curves; lower b) and higher thermostability(invariable b between treatments).Further,severe drought stress(20% FC) limited the survival of P.wilsonii.Our results indicate that P.wilsonii is more susceptible to high temperatures and soil drought stress.Planting P.crassifolia would be more expected to survive these conditions and hence be of greater benefit to forest stability if predicted increases in drought and temperature in northern China occur.

Daily SPEI Reveals Long-term Change in Drought Characteristics in Southwest China

Drought is the most widespread and insidious natural hazard, presenting serious challenges to ecosystems and human society. The daily Standardized Precipitation Evapotranspiration Index(SPEI) has been developed to identify the regional spatiotemporal characteristics of drought conditions from 1960 to 2016, revealing the variability in drought characteristics across Southwest China. Daily data from142 meteorological stations across the region were used to calculate the daily SPEI at the annual and seasonal time scale. The Mann-Kendall test and the trend statistics were then applied to quantify the significance of drought trends, with the following results. 1) The regionally averaged intensity and duration of all-drought and severe drought showed increasing trends, while the intensity and duration of extreme drought exhibited decreasing trends. 2) Mixed(increasing/decreasing) trends were detected, in terms of intensity and duration, in the three types of drought events. In general, no evidence of significant trends(P < 0.05) was detected in the drought intensity and duration over the last 55 years at the annual timescale. Seasonally, spring was characterized by a severe drought trend for all drought and severe drought conditions, while extreme drought events in spring and summer were very severe. All drought intensities and durations showed an increasing trend across most regions, except in the northwestern parts of Sichuan Province. However, the areal extent of regions suffering increasing trends in severe and extreme drought became relatively smaller. 3) We identified the following drought hotspots: Guangxi Zhuang Autonomous Region from the 1960 s to the 1990 s, respectively. Guangxi Zhuang Autonomous Region and Guizhou Province in the 1970 s and 1980 s, and Yunnan Province in the 2000 s. Finally, this paper can benefit operational drought characterization with a day-to-day drought monitoring index, enabling a more risk-based drought management strategy in the context of global warming.

Weakening sensitivity of global vegetation to long-term droughts

Droughts have dramatic direct and indirect impacts on vegetation and terrestrial ecosystem stability, including decreases in growth and subsequent decreases in CO_2 absorption. Although much research has been carried out on the response of vegetation to droughts, it remains unclear whether biomes are becoming more resistant or more vulnerable to drought. In this study, we used the Standardized Precipitation Evapotranspiration Index(SPEI, a multiscalar drought index) and the Normalized Difference Vegetation Index(NDVI, an indicator of vegetation growth) to detect the sensitivity of vegetation growth to droughts across 12–24 month timescales and to detect the change in this sensitivity over recent decades. We found that vegetation growth was most sensitive to 17–18 month droughts in water-limited regions, implying pronounce legacy effects from water conditions in previous years. In addition, we detected reduced coupling between drought and vegetation growth, probably caused by release moisture stress in water limited areas. Meanwhile, we observed a shortening of drought timescale to which vegetation most sensitively responded from an average of 18.1 to 17.2 months, suggesting the weakening of the drought legacy effect on vegetation growth. Results of this study contribute to the overall understanding of the resistance and resilience of ecosystems to drought conditions.

Global Change in Agricultural Flash Drought over the 21st Century

Agricultural flash droughts are high-impact phenomena, characterized by rapid soil moisture dry down. The ensuing dry conditions can persist for weeks to months, with detrimental effects on natural ecosystems and crop cultivation. Increases in the frequency of these rare events in a future warmer climate would have significant societal impact. This study uses an ensemble of 10 Coupled Model Intercomparison Project(CMIP) models to investigate the projected change in agricultural flash drought during the 21st century. Comparison across geographical regions and climatic zones indicates that individual events are preceded by anomalously low relative humidity and precipitation, with long-term trends governed by changes in temperature, relative humidity, and soil moisture. As a result of these processes, the frequency of both upperlevel and root-zone flash drought is projected to more than double in the mid-and high latitudes over the 21st century, with hot spots developing in the temperate regions of Europe, and humid regions of South America, Europe, and southern Africa.

Characterization and Propagation of Historical and Projected Droughts in the Umatilla River Basin, Oregon, USA

Climate change is expected to have long-term impacts on drought and wildfire risks in Oregon as summers continue to become warmer and drier. This paper investigates the projected changes in drought characteristics and drought propagation in the Umatilla River Basin in northeastern Oregon for mid-century(2030–2059) and late-century(2070–2099) climate scenarios. Drought characteristics for projected climates were determined using downscaled CMIP5 climate datasets from ten climate models and Soil and Water Assessment Tool to simulate effects on hydrologic processes. Short-term(three months) drought characteristics(frequency, duration, and severity) were analyzed using four drought indices, including the Standardized Precipitation Index(SPI-3), Standardized Precipitation-Evapotranspiration Index(SPEI-3), Standardized Streamflow Index(SSI-3), and the Standardized Soil Moisture Index(SSMI-3). Results indicate that short-term meteorological droughts are projected to become more prevalent, with up to a 20% increase in the frequency of SPI-3drought events. Short-term hydrological droughts are projected to become more frequent(average increase of 11% in frequency of SSI-3 drought events), more severe, and longer in duration(average increase of 8% for short-term droughts).Similarly, short-term agricultural droughts are projected to become more frequent(average increase of 28% in frequency of SSMI-3 drought events) but slightly shorter in duration(average decrease of 4%) in the future. Historically, drought propagation time from meteorological to hydrological drought is shorter than from meteorological to agricultural drought in most sub-basins. For the projected climate scenarios, the decrease in drought propagation time will likely stress the timing and capacity of water supply in the basin for irrigation and other uses.

Clinical manifestations,diagnosis and long-term prognosis of adult autoimmune enteropathy:Experience from Peking Union Medical College Hospital

BACKGROUND Autoimmune enteropathy(AIE)is a rare disease whose diagnosis and long-term prognosis remain challenging,especially for adult AIE patients.AIM To improve overall understanding of this disease’s diagnosis and prognosis.METHODS We retrospectively analyzed the clinical,endoscopic and histopathological characteristics and prognoses of 16 adult AIE patients in our tertiary medical center between 2011 and 2023,whose diagnosis was based on the 2007 diagnostic criteria.RESULTS Diarrhea in AIE patients was characterized by secretory diarrhea.The common endoscopic manifestations were edema,villous blunting and mucosal hyperemia in the duodenum and ileum.Villous blunting(100%),deep crypt lymphocytic infiltration(67%),apoptotic bodies(50%),and mild intraepithelial lymphocytosis(69%)were observed in the duodenal biopsies.Moreover,there were other remarkable abnormalities,including reduced or absent goblet cells(duodenum 94%,ileum 62%),reduced or absent Paneth cells(duodenum 94%,ileum 69%)and neutrophil infiltration(duodenum 100%,ileum 69%).Our patients also fulfilled the 2018 diagnostic criteria but did not match the 2022 diagnostic criteria due to undetectable anti-enterocyte antibodies.All patients received glucocorticoid therapy as the initial medication,of which 14/16 patients achieved a clinical response in 5(IQR:3-20)days.Immunosuppressants were administered to 9 patients with indications of steroid dependence(6/9),steroid refractory status(2/9),or intensified maintenance medication(1/9).During the median of 20.5 months of followup,2 patients died from multiple organ failure,and 1 was diagnosed with non-Hodgkin’s lymphoma.The cumulative relapse-free survival rates were 62.5%,55.6%and 37.0%at 6 months,12 months and 48 months,respectively.CONCLUSION Certain histopathological findings,including a decrease or disappearance of goblet and Paneth cells in intestinal biopsies,might be potential diagnostic criteria for adult AIE.The long-term prognosis is still unsatisfactory despite corticosteroid and immunosuppressant medications,which highlights the need for early diagnosis and novel medications.

Grain Yield,Biomass Accumulation,and Leaf Photosynthetic Characteristics of Rice under Combined Salinity-Drought Stress

Simultaneous stresses of salinity and drought often coincide during rice-growing seasons in saline lands,primarily due to insufficient water resources and inadequate irrigation facilities.Consequently,combined salinity-drought stress poses a major threat to rice production.In this study,two salinity levels(NS,non-salinity;HS,high salinity)along with three drought treatments(CC,control condition;DJ,drought stress imposed at jointing;DH,drought stress imposed at heading)were performed to investigate their combined influences on leaf photosynthetic characteristics,biomass accumulation,and rice yield formation.Salinity,drought,and their combination led to a shortened growth period from heading to maturity,resulting in a reduced overall growth duration.Grain yield was reduced under both salinity and drought stress,with a more substantial reduction under the combined salinity-drought stress.The combined stress imposed at heading caused greater yield losses in rice compared with the stress imposed at jointing.Additionally,the combined salinity-drought stress induced greater decreases in shoot biomass accumulation from heading to maturity,as well as in shoot biomass and nonstructural carbohydrate(NSC)content in the stem at heading and maturity.However,it increased the harvest index and NSC remobilization reserve.Salinity and drought reduced the leaf area index and SPAD value of flag leaves and weakened the leaf photosynthetic characteristics as indicated by lower photosynthetic rates,transpiration rates,and stomatal conductance.These reductions were more pronounced under the combined stress.Salinity,drought,and especially their combination,decreased the activities of ascorbate peroxidase,catalase,and superoxide dismutase,while increasing the contents of malondialdehyde,hydrogen peroxide,and superoxide radical.Our results indicated a more significant yield loss in rice when subjected to combined salinity-drought stress.The individual and combined stresses of salinity and drought diminished antioxidant enzyme activities,inhibited leaf photosynthetic functions,accelerated leaf senescence,and subsequently lowered assimilate accumulation and grain yield.

Exogenous melatonin improves cotton yield under drought stress by enhancing root development and reducing root damage

The exogenous application of melatonin by the root drenching method is an effective way to improve crop drought resistance.However,the optimal concentration of melatonin by root drenching and the physiological mechanisms underlying melatonin-induced drought tolerance in cotton(Gossypium hirsutum L.)roots remain elusive.This study determined the optimal concentration of melatonin by root drenching and explored the protective effects of melatonin on cotton roots.The results showed that 50μmol L-1 melatonin was optimal and significantly mitigated the inhibitory effect of drought on cotton seedling growth.Exogenous melatonin promoted root development in drought-stressed cotton plants by remarkably increasing the root length,projected area,surface area,volume,diameter,and biomass.Melatonin also mitigated the drought-weakened photosynthetic capacity of cotton and regulated the endogenous hormone contents by regulating the relative expression levels of hormone-synthesis genes under drought stress.Melatonin-treated cotton seedlings maintained optimal enzymatic and non-enzymatic antioxidant capacities,and produced relatively lower levels of reactive oxygen species and malondialdehyde,thus reducing the drought stress damage to cotton roots(such as mitochondrial damage).Moreover,melatonin alleviated the yield and fiber length declines caused by drought stress.Taken together,these findings show that root drenching with exogenous melatonin increases the cotton yield by enhancing root development and reducing the root damage induced by drought stress.In summary,these results provide a foundation for the application of melatonin in the field by the root drenching method.

Assessing the Performance of CMIP6 Models in Simulating Droughts across Global Drylands

Both the attribution of historical change and future projections of droughts rely heavily on climate modeling. However,reasonable drought simulations have remained a challenge, and the related performances of the current state-of-the-art Coupled Model Intercomparison Project phase 6(CMIP6) models remain unknown. Here, both the strengths and weaknesses of CMIP6 models in simulating droughts and corresponding hydrothermal conditions in drylands are assessed.While the general patterns of simulated meteorological elements in drylands resemble the observations, the annual precipitation is overestimated by ~33%(with a model spread of 2.3%–77.2%), along with an underestimation of potential evapotranspiration(PET) by ~32%(17.5%–47.2%). The water deficit condition, measured by the difference between precipitation and PET, is 50%(29.1%–71.7%) weaker than observations. The CMIP6 models show weaknesses in capturing the climate mean drought characteristics in drylands, particularly with the occurrence and duration largely underestimated in the hyperarid Afro-Asian areas. Nonetheless, the drought-associated meteorological anomalies, including reduced precipitation, warmer temperatures, higher evaporative demand, and increased water deficit conditions, are reasonably reproduced. The simulated magnitude of precipitation(water deficit) associated with dryland droughts is overestimated by 28%(24%) compared to observations. The observed increasing trends in drought fractional area,occurrence, and corresponding meteorological anomalies during 1980–2014 are reasonably reproduced. Still, the increase in drought characteristics, associated precipitation and water deficit are obviously underestimated after the late 1990s,especially for mild and moderate droughts, indicative of a weaker response of dryland drought changes to global warming in CMIP6 models. Our results suggest that it is imperative to employ bias correction approaches in drought-related studies over drylands by using CMIP6 outputs.

Overexpression of the transcription factor MdWRKY115 improves drought and osmotic stress tolerance by directly binding to the MdRD22 promoter in apple

Abiotic stress reduces plant yield and quality.WRKY transcription factors play key roles in abiotic stress responses in plants,but the molecular mechanisms by which WRKY transcription factors mediate responses to drought and osmotic stresses in apple(Malus×domestica Borkh.)remain unclear.Here,we functionally characterized the apple GroupⅢWRKY gene MdWRKY115.qRT-PCR analysis showed that MdWRKY115 expression was up-regulated by drought and osmotic stresses.GUS activity analysis revealed that the promoter activity of MdWRKY115 was enhanced under osmotic stress.Subcellular localization and transactivation assays indicated that MdWRKY115 was localized to the nucleus and had a transcriptional activity domain at the N-terminal region.Transgenic analysis revealed that the overexpression of MdWRKY115 in Arabidopsis plants and in apple callus markedly enhanced their tolerance to drought and osmotic stresses.DNA affinity purification sequencing showed that MdWRKY115 binds to the promoter of the stress-related gene MdRD22.This binding was further verified by an electrophoretic mobility shift assay.Collectively,these findings suggest that MdWRKY115 is an important regulator of osmotic and drought stress tolerance in apple.

Resilience and response:Unveiling the impacts of extreme droughts on forests through integrated dendrochronological and remote sensing analyses

Extreme droughts are anticipated to have detrimental impacts on forest ecosystems,especially in water-limited regions,due to the influence of climate change.However,considerable uncertainty remains regarding the patterns in species-specific responses to extreme droughts.Here,we conducted a study integrating dendrochronology and remote sensing methods to investigate the mosaic-distributed maple-oak(native)natural forests and poplar plantations(introduced)in the Horqin Sandy Land,Northeast China.We assessed the impacts of extreme droughts on tree performances by measuring interannual variations in radial growth and vegetation index.The results showed that precipitation and self-calibrated palmer drought severity index(scPDSI)are the major factors influencing tree-ring width index(RWI)and normalized difference vegetation index(NDVI).The severe droughts between 2000 and 2004 resulted in reduced RWI in the three studied tree species as well as led to NDVI reductions in both the maple-oak natural forests and the poplar plantations.The RWI reached the nadir during the2000-2004 severe droughts and remained at low levels two years after the severe drought,creating a legacy effect.In contrast to the lack of significant correlation between RWI and scPDSI,NDVI exhibited a significant positive correlation with scPDSI indicating the greater sensitivity of canopy performance to droughts than radial growth.Furthermore,interspecific differences in RWI and NDVI responses were observed,with the fast-growing poplar species experiencing a more significant RWI decrease and more negative NDVI anomaly during severe droughts than native species,highlighting the species-specific trade-offs between drought resilience and growth rate.This study emphasizes the importance of combining tree-level radial growth with landscape-scale canopy remote sensing to understand forest resilience and response.Our study improves our understanding of forest responses to extreme drought and highlights species differences in climate responses,offering crucial insights for optimizing species selection in sustainable afforestation and forest management in water-limited regions under the influence of climate change.

Impacts of Future Changes in Heavy Precipitation and Extreme Drought on the Economy over South China and Indochina

Heavy precipitation and extreme drought have caused severe economic losses over South China and Indochina(INCSC)in recent decades.Given the areas with large gross domestic product(GDP)in the INCSC region are distributed along the coastline and greatly affected by global warming,understanding the possible economic impacts induced by future changes in the maximum consecutive 5-day precipitation(RX5day)and the maximum consecutive dry days(CDD)is critical for adaptation planning in this region.Based on the latest data released by phase 6 of the Coupled Model Intercomparison Project(CMIP6),future projections of precipitation extremes with bias correction and their impacts on GDP over the INCSC region under the fossil-fueled development Shared Socioeconomic Pathway(SSP5-8.5)are investigated.Results indicate that RX5day will intensify robustly throughout the INCSC region,while CDD will lengthen in most regions under global warming.The changes in climate consistently dominate the effect on GDP over the INCSC region,rather than the change of GDP.If only considering the effect of climate change on GDP,the changes in precipitation extremes bring a larger impact on the economy in the future to the provinces of Hunan,Jiangxi,Fujian,Guangdong,and Hainan in South China,as well as the Malay Peninsula and southern Cambodia in Indochina.Thus,timely regional adaptation strategies are urgent for these regions.Moreover,from the sub-regional average viewpoint,over two thirds of CMIP6 models agree that maintaining a lower global warming level will reduce the economic impacts from heavy precipitation over the INCSC region.

Extreme Meteorological Drought Events over China(1951-2022):Migration Patterns,Diversity of Temperature Extremes,and Decadal Variations

Recently,extreme meteorological droughts have affected China,causing terrible socioeconomic impacts.Despite previous research on the spatiotemporal characteristics and mechanisms of drought,two crucial issues remain seldom explored.First,an event-oriented drought chronology with detailed spatiotemporal evolutions is urgently required.Second,the complex migration patterns and diversity of synchronous temperature extremes need to be quantitatively investigated.Accordingly,the main achievements of our investigation are as follows.We produced an event-oriented set of extreme meteorological droughts over China through the application of a newly developed 3D DBSCAN-based detection method(deposited on https://doi.org/10.25452/figshare.plus.25512334),which was verified with a historical atlas and monographs on a case-by-case basis.In addition,distinctive migration patterns(i.e.,stationary/propagation types)are identified and ranked,considering the differences in latitudinal zones and coastal/inland locations.We also analyze the diversity of synchronous temperature extremes(e.g.,hotness and coldness).Notably,an increasing trend in hot droughts occurred over China since the late 1990s,predominantly appearing to the south of 30°N and north of 40°N.All drought events and synchronous temperature extremes are ranked using a comprehensive magnitude index,with the 2022 summer-autumn Yangtze River hot drought being the hottest.Furthermore,Liang-Kleeman information flow-based causality analysis emphasizes key areas where the PDO and AMO influenced decadal variations in coverages of droughts and temperature extremes.We believe that the achievements in this study may offer new insights into sequential mechanism exploration and prediction-related issues.

E3 ubiquitin ligase PbrATL18 is a positive factor in pear resistance to drought and Colletotrichum fructicola infection

The Arabidopsis Toxicos en Levadura(ATL)protein is a subfamily of the E3 ubiquitin ligases,which exists widely in plants and is extensively involved in plant growth and development.Although the ATL family has been identified in other species,such as Arabidopsis,Oryza sativa,and grapevine,few reports on pear ATL gene families have been reported.In this study,92 PbrATL genes were identified and analyzed from the Pyrus breschneideri genome.Motif analysis and phylogenetic tree generation divided them into nine subgroups,and chromosome localization analysis showed that the 92 PbrATL genes were distributed in 16 of 17 pear chromosomes.Transcriptome data and quantitative real-time polymerase chain reaction(qRT-PCR)experiments demonstrated that PbrATL18,PbrATL41,and PbrATL88 were involved in both pear drought resistance and Colletotrichum fructicola infection.In addition,Arabidopsis thaliana overexpressing PbrATL18 showed greater resistance to drought stress than the wild type(WT),and PbrATL18-silenced pear seedlings showed greater sensitivity to drought and C.fructicola infection than the controls.PbrATL18 regulated plant resistance by regulating chitinase(CHI),phenylalanine ammonia-lyase(PAL),polyphenol oxidase(PPO),catalase(CAT),peroxidase(POD),and superoxide dismutase(SOD)activities.This study provided a reference for further exploring the functions of the PbrATL gene in drought resistance and C.fructicola infection.

The ZOS7-MYB60 module confers drought-stress tolerance in rice

Shanlan upland rice is an important landrace resource with high drought stress(DS)tolerance.Despite its importance,genes responsible for yield in Shanlan upland rice have yet to be discovered.Our previous study identified a drought-responsive zinc finger protein,ZOS7,as highly expressed in Shanlandao upland rice.However,the function of this gene in controlling drought tolerance remains largely unexplored.In this study,we found that overexpressing ZOS7,a drought-responsive zinc finger protein,in rice increased biomass and yield under drought stress.Co-overexpressing ZOS7 and MYB60,encoding a protein with which ZOS7 interacted,intensified the yield increase.ZOS7 and MYB60 appear to form a module that confers drought tolerance by regulating stomatal density and wax biosynthesis.The ZOS7-MYB60module could be used in molecular breeding for drought tolerance in rice.

Development of a new Cox model for predicting long-term survival in hepatitis cirrhosis patients underwent transjugular intrahepatic portosystemic shunts

BACKGROUND Transjugular intrahepatic portosystemic shunt(TIPS)placement is a procedure that can effectively treat complications of portal hypertension,such as variceal bleeding and refractory ascites.However,there have been no specific studies on predicting long-term survival after TIPS placement.AIM To establish a model to predict long-term survival in patients with hepatitis cirrhosis after TIPS.METHODS A retrospective analysis was conducted on a cohort of 224 patients who un-derwent TIPS implantation.Through univariate and multivariate Cox regression analyses,various factors were examined for their ability to predict survival at 6 years after TIPS.Consequently,a composite score was formulated,encompassing the indication,shunt reasonability,portal venous pressure gradient(PPG)after TIPS,percentage decrease in portal venous pressure(PVP),indocyanine green retention rate at 15 min(ICGR15)and total bilirubin(Tbil)level.Furthermore,the performance of the newly developed Cox(NDC)model was evaluated in an in-ternal validation cohort and compared with that of a series of existing models.RESULTS The indication(variceal bleeding or ascites),shunt reasonability(reasonable or unreasonable),ICGR15,post-operative PPG,percentage of PVP decrease and Tbil were found to be independent factors affecting long-term survival after TIPS placement.The NDC model incorporated these parameters and successfully identified patients at high risk,exhibiting a notably elevated mortality rate following the TIPS procedure,as observed in both the training and validation cohorts.Additionally,in terms of predicting the long-term survival rate,the performance of the NDC model was significantly better than that of the other four models[Child-Pugh,model for end-stage liver disease(MELD),MELD-sodium and the Freiburg index of post-TIPS survival].CONCLUSION The NDC model can accurately predict long-term survival after the TIPS procedure in patients with hepatitis cirrhosis,help identify high-risk patients and guide follow-up management after TIPS implantation.

Involvement of the ABA-and H_(2)O_(2)-Mediated Ascorbate-Glutathione Cycle in the Drought Stress Responses of Wheat Roots

Abscisic acid(ABA),hydrogen peroxide(H_(2)O_(2)) and ascorbate(AsA)–glutathione(GSH)cycle are widely known for their participation in various stresses.However,the relationship between ABA and H_(2)O_(2) levels and the AsA–GSH cycle under drought stress in wheat has not been studied.In this study,a hydroponic experiment was conducted in wheat seedlings subjected to 15%polyethylene glycol(PEG)6000–induced dehydration.Drought stress caused the rapid accumulation of endogenous ABA and H_(2)O_(2) and significantly decreased the number of root tips compared with the control.The application of ABA significantly increased the number of root tips,whereas the application of H_(2)O_(2) markedly reduced the number of root tips,compared with that under 15%PEG-6000.In addition,drought stress markedly increased the DHA,GSH and GSSG levels,but decreased the AsA levels,AsA/DHA and GSH/GSSG ratios compared with those in the control.The activities of the four enzymes in the AsA–GSH cycle were also markedly increased under drought stress,including glutathione reductase(GR),ascorbate peroxidase(APX),monodehydroascorbate reductase(MDHAR)and dehydroascorbate reductase(DHAR),compared with those in the control.However,the application of an ABA inhibitor significantly inhibited GR,DHAR and APX activities,whereas the application of an H_(2)O_(2) inhibitor significantly inhibited DHAR and MDHAR activities.Furthermore,the application of ABA inhibitor significantly promoted the increases of H_(2)O_(2) and the application of H_(2)O_(2) inhibitor significantly blocked the increases of ABA,compared with those under 15% PEG-6000.Taken together,the results indicated that ABA and H_(2)O_(2) probably interact under drought stress in wheat;and both of them can mediate drought stress by modulating the enzymes in AsA–GSH cycle,where ABA acts as the main regulator of GR,DHAR,and APX activities,and H_(2)O_(2) acts as the main regulator of DHAR and MDHAR activities.

Long-term outcomes after endoscopic removal of malignant colorectal polyps:Results from a 10-year cohort

BACKGROUND Choosing an optimal post-polypectomy management strategy of malignant colorectal polyps is challenging,and evidence regarding a surveillance-only strategy is limited.AIM To evaluate long-term outcomes after endoscopic removal of malignant colorectal polyps.METHODS A single-center retrospective cohort study was conducted to evaluate outcomes after endoscopic removal of malignant colorectal polyps between 2010 and 2020.Residual disease rate and nodal metastases after secondary surgery and local and distant recurrence rate for those with at least 1 year of follow-up were invest-igated.Event rates for categorical variables and means for continuous variables with 95%confidence intervals were calculated,and Fisher’s exact test and Mann-Whitney test were performed.Potential risk factors of adverse outcomes were RESULTS In total,135 lesions(mean size:22.1 mm;location:42%rectal)from 129 patients(mean age:67.7 years;56%male)were enrolled.The proportion of pedunculated and non-pedunculated lesions was similar,with en bloc resection in 82%and 47%of lesions,respectively.Tumor differentiation,distance from resection margins,depth of submucosal invasion,lymphovascular invasion,and budding were reported at 89.6%,45.2%,58.5%,31.9%,and 25.2%,respectively.Residual tumor was found in 10 patients,and nodal metastasis was found in 4 of 41 patients who underwent secondary surgical resection.Univariate analysis identified piecemeal resection as a risk factor for residual malignancy(odds ratio:1.74;P=0.042).At least 1 year of follow-up was available for 117 lesions from 111 patients(mean follow-up period:5.59 years).Overall,54%,30%,30%,11%,and 16%of patients presented at the 1-year,3-year,5-year,7-year,and 9-10-year surveillance examinations.Adverse outcomes occurred in 9.0%(local recurrence and dissemination in 4 patients and 9 patients,respectively),with no difference between patients undergoing secondary surgery and surveillance only.CONCLUSION Reporting of histological features and adherence to surveillance colonoscopy needs improvement.Long-term adverse outcome rates might be higher than previously reported,irrespective of whether secondary surgery was performed.