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ObjectivesThe aim of this study is to review the evidence on the use of antithrombotic therapy and risk of device-related thrombosis after left atrial appendage closure.BackgroundLeft atrial appendage closure (LAAC) is increasingly performed for stroke prevention in patients with nonvalvular atrial fibrillation, especially those who cannot tolerate or are ineligible for oral anticoagulation.MethodsAfter device implantation for LAAC, different antithrombotic regimens with varying duration of therapy are currently used. Such selection depends on patients’ risk for bleeding and physicians’ choice.ResultsDevice-related thrombosis remains an Achilles’ heel of LAAC, and the etiology remains incompletely understood. Dual-antiplatelet therapy, and direct oral anticoagulation may have similar safety and device-related thrombosis occurrence in real-world LAAC registries compared with warfarin and aspirin. Device imaging surveillance should be routinely performed to assess for device-related thrombosis, which if diagnosed should be treated aggressively, as it is associated with higher thromboembolic risks.ConclusionsGiven the uncertainties and therapeutic dilemma, the authors provide an in-depth discussion of the options and rationale for antithrombotic therapy post-LAAC.  相似文献   
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Limited water availability, population growth, and climate change have resulted in freshwater crises in many countries. Jordan’s situation is emblematic, compounded by conflict-induced population shocks. Integrating knowledge across hydrology, climatology, agriculture, political science, geography, and economics, we present the Jordan Water Model, a nationwide coupled human–natural-engineered systems model that is used to evaluate Jordan’s freshwater security under climate and socioeconomic changes. The complex systems model simulates the trajectory of Jordan’s water system, representing dynamic interactions between a hierarchy of actors and the natural and engineered water environment. A multiagent modeling approach enables the quantification of impacts at the level of thousands of representative agents across sectors, allowing for the evaluation of both systemwide and distributional outcomes translated into a suite of water-security metrics (vulnerability, equity, shortage duration, and economic well-being). Model results indicate severe, potentially destabilizing, declines in freshwater security. Per capita water availability decreases by approximately 50% by the end of the century. Without intervening measures, >90% of the low-income household population experiences critical insecurity by the end of the century, receiving <40 L per capita per day. Widening disparity in freshwater use, lengthening shortage durations, and declining economic welfare are prevalent across narratives. To gain a foothold on its freshwater future, Jordan must enact a sweeping portfolio of ambitious interventions that include large-scale desalinization and comprehensive water sector reform, with model results revealing exponential improvements in water security through the coordination of supply- and demand-side measures.

Jordan, a nearly land-locked nation, has a tenuous freshwater future. The country’s water challenges stem from having extremely limited natural water availability with few alternatives for generating new supply and dependence on transboundary rivers and groundwater (Fig. 1A). Flows in the lower Jordan River, which marks Jordan’s western border with Israel and the West Bank, are estimated to have declined by nearly 90% since predevelopment conditions (1), mostly due to the diversion of the upper Jordan River into the National Water Carrier by Israel (2). The Yarmouk River tributary, currently Jordan’s primary surface-water source, is also largely captured by upstream Syria (36). Throughout the country, groundwater is being rapidly depleted, with observed groundwater-level declines of 0.9 to 3.5 m/y since 1995 in the country’s most highly productive aquifer (7, 8). To the south, Jordan competes with Saudi Arabia for shared groundwater from the fossil Disi regional aquifer (9). Jordan has long sought construction of the Red Sea–Dead Sea conveyance project, which would desalinate Red Sea water, transport the freshwater north to Amman, and dispose of the saline brine to the Dead Sea. Although first conceived of in the 1960s, project costs and fragile international cooperation have stood in the way.Open in a separate windowFig. 1.Map of Jordan and conceptual model. (A) Jordan relies on surface-water sources (primarily the Yarmouk River) and groundwater wells for water supply. The most recent record of total freshwater use from Jordan’s MWI is 1,054 MCM for 2017, with groundwater contributing 59% of the total supply, surface water 27%, and treated wastewater 14%. The domestic sector uses 45% of all water, agriculture 52%, and industry 3%. Groundwater is the primary source for the domestic sector, constituting over 70% of its supply. For the agricultural sector, groundwater constitutes 46% of the supply for irrigation, surface water 28%, and treated wastewater 26%. (B) The JWM consists of two types of modules: human modules (white rectangles) and biophysical modules (gray rectangles) of natural and engineered physical phenomena. The systems model includes interactions between modules, distinguished by endogenous human decisions (blue lines), endogenous physical flows and production (green lines), and exogenous scenarios (pink lines) and human interventions (yellow lines).Climate change and population growth further threaten Jordan’s tenuous situation (10). Rainfall decline in Jordan is already evident over the past century (11, 12), while climate models predict further increased temperatures with doubling in the frequency, duration, and intensity of droughts by 2100 (13). Jordan’s growing population has been punctuated by sudden, large refugee influxes (10, 14). In 2010, Jordan’s population was 7.2 million, growing to over 10.8 million by 2020, a period when at least 1.1 million Syrian refugees fled Syria’s 2011 war to Jordan (2, 15). In response to water shortage, Jordan has implemented significant water-supply efficiencies. In Amman, the largest city and capital, over 95% of wastewater is treated and recycled. However, Jordan’s water-distribution system is inefficient and intermittent. Approximately 50% of Jordan’s piped supply is lost as “nonrevenue water” (NRW), due to either physical factors (e.g., pipeline leaks) or administrative issues (e.g., water theft, incorrect meter readings, or underbilling). On average, households in the capital of Amman receive piped water for only 36 h per week (16), with lower-income neighborhoods receiving as low as 24 h of municipal supply, while higher-income households receive up to 5 d of uninterrupted supply per week (17). As a result, urban users purchase expensive water delivered by tanker trucks that obtain water from private agricultural wells through both formal and informal tanker-water markets (17, 18). Ecological impacts related to both groundwater and surface-water withdrawals by Jordan and upstream riparian nations in the Jordan River Basin have been severe, with notable examples including the drying of the Azraq Oasis, a Ramsar wetland (19, 20), and the shrinking of the Dead Sea, whose shoreline is receding by 1 m/y (21).The situation in Jordan is emblematic of water crises around the world, in which rapid population growth, intensifying water use, sudden demographic shocks, climate change, transboundary water competition, and institutional challenges pose serious threats to freshwater security (2228). In the face of such global changes, an overarching sustainability goal is the long-term provision of freshwater as formalized in the 2015 Sustainable Development Goals (29). Given the complex and interacting physical and socioeconomic facets of such a challenge, there has been a growing call for analytic frameworks to evaluate freshwater systems that account for both the physical processes that govern freshwater supply and the human institutions and behaviors that influence the management, allocation, and consumption of water (3036). Here, we present such a coupled human–natural-engineered system framework to explore the long-term impacts of a suite of policy interventions aimed at achieving freshwater security in Jordan in the face of anticipated changes in climate, population, and the economy.  相似文献   
4.
Patient selection for combined liver–kidney transplantation (CLKT) is a current issue on the background of organ shortage. This study aimed to compare outcomes and post‐transplant renal function for patients receiving CLKT and liver transplantation alone (LTA) based on native renal function using estimated glomerular filtration rate (eGFR) stratification. Using the UK National transplant database (NHSBT) 6035 patients receiving a LTA (N = 5912; 98%) or CLKT (N = 123; 2%) [2001–2013] were analysed, and stratified by KDIGO stages of eGFR at transplant (eGFR group‐strata). There was no difference in patient/graft survival between LTA and CLKT in eGFR group‐strata (P > 0.05). Of 377 patients undergoing renal replacement therapy (RRT) at time of transplantation, 305 (81%) and 72 (19%) patients received LTA and CLKT respectively. A significantly greater proportion of CLKT patients had severe end‐stage renal disease (eGFR < 30 ml/min/1.73 m2) at 1 year post‐transplant compared to LTA (9.5% vs. 5.7%, P = 0.001). Patient and graft survival benefit for patients on RRT at transplantation was favouring CLKT versus LTA (P = 0.038 and P = 0.018, respectively) but the renal function of the long‐term survivors was not superior following CLKT. The data does not support CLKT approach based on eGFR alone, and the advantage of CLKT appear to benefit only those who are on established RRT at the time of transplant.  相似文献   
5.
Bulletin of Environmental Contamination and Toxicology - The safe utilization and risk assessment of produced water (PW) from oil and gas fields for desert irrigation have received increasing...  相似文献   
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Full-left-full-right split liver transplantation (FSLT) for adult recipients, may increase the availability of liver grafts, reduce waitlist time, and benefit recipients with below-average body weight. However, FSLT may lead to impaired graft and patient survival. This study aims to assess outcomes after FSLT. Five databases were searched to identify studies concerning FSLT. Incidences of complications, graft- and patient survival were assessed. Discrete data were pooled with random-effect models. Graft and patient survival after FSLT were compared with whole liver transplantation (WLT) according to the inverse variance method. Vascular complications were reported in 25/273 patients after FSLT (Pooled proportion: 6.9%, 95%CI: 3.1–10.7%, I2: 36%). Biliary complications were reported in 84/308 patients after FSLT (Pooled proportion: 25.6%, 95%CI: 19–32%, I2: 44%). Pooled proportions of graft and patient survival after 3 years follow-up were 72.8% (95%CI: 67.2–78.5, = 231) and 77.3% (95%CI: 66.7–85.8, = 331), respectively. Compared with WLT, FSLT was associated with increased graft loss (pooled HR: 2.12, 95%CI: 1.24–3.61, = 0.006, = 189) and patient mortality (pooled HR: 1.81, 95%CI: 1.17–2.81, = 0.008, = 289). FSLT was associated with high incidences of vascular and biliary complications. Nevertheless, long-term patient and graft survival appear acceptable and justify transplant benefit in selected patients.  相似文献   
8.
High-risk combinations of recipient and graft characteristics are poorly defined for liver retransplantation (reLT) in the current era. We aimed to develop a risk model for survival after reLT using data from the European Liver Transplantation Registry, followed by internal and external validation. From 2006 to 2016, 85 067 liver transplants were recorded, including 5581 reLTs (6.6%). The final model included seven predictors of graft survival: recipient age, model for end-stage liver disease score, indication for reLT, recipient hospitalization, time between primary liver transplantation and reLT, donor age, and cold ischemia time. By assigning points to each variable in proportion to their hazard ratio, a simplified risk score was created ranging 0–10. Low-risk (0–3), medium-risk (4–5), and high-risk (6–10) groups were identified with significantly different 5-year survival rates ranging 56.9% (95% CI 52.8–60.7%), 46.3% (95% CI 41.1–51.4%), and 32.1% (95% CI 23.5–41.0%), respectively (< 0.001). External validation showed that the expected survival rates were closely aligned with the observed mortality probabilities. The Retransplantation Risk Score identifies high-risk combinations of recipient- and graft-related factors prognostic for long-term graft survival after reLT. This tool may serve as a guidance for clinical decision-making on liver acceptance for reLT.  相似文献   
9.
This study reports the first evaluation of sperm hyaluronan binding assay (HBA) for predicting the fertility of Nili-Ravi buffalo bulls in relation to standard parameters of sperm quality. Cryopreserved semen doses of low (n = 6), medium (n = 3) and high fertility (n = 8) bulls based on their respective return rates were used. Significantly, more spermatozoa bound to hyaluronan from the most fertile bulls (57.15% ± 1.44) compared with medium (42.46% ± 1.08) and low fertility bulls (29.70% ± 0.78). A strongly positive correlation (r = .824, p < .01) was found between HBA and fertility that predicts a 67.9% variability (r2 = .679, p < .01) in fertility. HBA was also strongly positively correlated with sperm viability (r = .679, p < .01) followed by their live/dead ratio (r = .637, p < .01), uncapacitated spermatozoa (r = .631, p < .01), normal apical ridge (r = .459, p < .01), motility (r = .434, p < .01), mature spermatozoa with low residual histones (r = .364, p < .01), high plasma membrane integrity (r = .316, p < .01) and nonfragmented DNA levels (r = .236, p < .05). It was negatively correlated with spermatozoa having reacted acrosome (r = −.654, p < .01). A fertility model built using a combination of sperm HBA and either sperm livability or viability predicts, respectively, 86.1% (r2 = .861, p < .01) and 85.9% (r2 = .859, p < .01) variability in buffalo bull fertility. In conclusion, sperm HBA may prove to be a single robust predictor of Nili-Ravi buffalo bull fertility.  相似文献   
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