Alginate-encapsulated biochar as an effective soil ameliorant for reducing Pb phytoavailability to lettuce (Lactuca sativa L.).

The alginate-biochar formulation for metal removal from aquatic environments has been widely tried but its use for lowering phytoavailability of metals in the soil-crop continuum is limited. Biochar has been increasingly used as a soil amendment due to its potential for soil carbon sequestration and sorption capacity. Handling of powdery biochar as a soil top-dressing material is, however, cumbersome and vulnerable to loss by water and wind. In this experiment, biochar powder, which was pyrolyzed from oak trees, was encapsulated into beads with alginate, which is a naturally occurring polysaccharide found in brown algae. Both batch and pot experiments were conducted to examine the effects of the alginate-encapsulated biochar beads (BB), as compared to its original biochar powdery form (BP), on the Pb adsorption capacity and phytoavailability of soil Pb to lettuce (Lactuca sativa L.). The BB treatment improved reactivity about six times due to a higher surface area (287 m2 g-1) and five times due to a higher cation exchange capacity (50 cmolc kg-1) as compared to the BP treatment. The maximum sorption capacity of Pb was increased to 152 from 81 mg g-1 because of surface chemosorption. Adsorption of Pb onto BB followed multiple first-order kinetics and comprised fast and slow steps. More than 60% of the Pb was adsorbed in the fast step, i.e., within 3 h. Also, the BB treatment, up to the 5% level (w/w), increased soil pH from 5.4 to 6.5 and lowered the phytoavailable fraction of Pb in soil from 5.7 to 0.3 mg kg-1. The Pb concentrations in lettuce cultivated at 5% for the BP and BB treatments were similar but 63 and 66% lower, respectively, than those of the control soil. The results showed that the encapsulation of biochar with alginate enhanced adsorption by the biochar.

Co-Responses of Soil Organic Carbon Pool and Biogeochemistry to Different Long-Term Fertilization Practices in Paddy Fields.

Long-term application of soil organic amendments (SOA) can improve the formation of soil organic carbon (SOC) pool as well as soil fertility and health of paddy lands. However, the effects of SOA may vary with the input amount and its characteristics. In this work, a descriptive field research was conducted during one cropping season to investigate the responses of various SOC fractions to different long-term fertilization practices in rice fields and their relationships with soil biogeochemical properties and the emission of greenhouse gases (GHG). The field sites included two conventional paddies applied with chemical fertilizer (CF) or CF + rice straw (RS) and six organic agriculture paddies applied with oilseed cake manure (OCM) + wheat straw (WS), cow manure (CM) + WS, or CM + RS. The two paddy soils treated with CM + RS had significantly higher concentrations of recalcitrant to labile C forms, such as loss-on-ignition C (LOIC; 56-73 g kg-1), Walkley-Black C (WBC; 20-25 g kg-1), permanganate oxidizable C (POXC; 835-853 mg kg-1), and microbial biomass carbon (MBC; 133-141 mg kg-1), than soils treated with other SOA. Likewise, long-term application of CM + RS seemed to be the best for regulating soil fertility parameters, such as ammonium (11-141 mg kg-1); phosphate (61-106 mg kg-1); and soluble Ca, K, and Mg (7-10, 0.5-1.2, and 1.9-3.8 mg kg-1, respectively), although the results varied with the location and soil properties of rice fields. Additionally, the two paddy sites had the largest cumulative methane emission (754-762 kg ha-1), seemingly attributed to increased microbial biomass and labile C fractions. The significant correlations of most SOC fractions with soil microbial biomass, trophic factors, and methane emissions were confirmed with multivariate data analysis. It was also possible to infer that long-term SOA application, especially with CM + RS, enhanced interaction in belowground paddy fields, contributing to soil fertility and rice production sustainability. Based on our findings, we suggest the need for analysis of various types of SOC fractions to efficiently manage soil fertility and quality of paddy fields, C sequestration, and GHG emissions.

The Prescription Characteristics, Efficacy and Safety of Spironolactone in Real-World Patients With Acute Heart Failure Syndrome: A Prospective Nationwide Cohort Study.

Background: Randomized clinical trials of spironolactone showed significant mortality reduction in patients with heart failure with reduced ejection fraction. However, its role in acute heart failure syndrome (AHFS) is largely unknown. Aim: To investigate the prescription characteristics, efficacy and safety of spironolactone in real-world patients with AHFS. Methods: 5,136 AHFS patients who survived to hospital discharge using a nationwide prospective registry in Korea were analyzed. The primary efficacy outcome was 3-year all-cause mortality. Results: Spironolactone was prescribed in 2,402 (46.8%) at discharge: <25 mg in 890 patients (37.1%), ≥25 mg, and <50 mg in 1,154 patients (48.0%), and ≥50 mg in 358 patients (14.9%). Patients treated with spironolactone had a lower proportion of chronic renal failure and renal replacement therapy during hospitalization and had lower serum creatinine level than those who did not. In overall patients, 3-year mortality was not different in both groups (35.9 vs. 34.5%, P = 0.279). The incidence of renal injury and hyperkalemia was 2.2% and 4.3%, respectively, at the first follow-up visit. The treatment effect of spironolactone on mortality was different across subpopulations according to LVEF. The use of spironolactone was associated with a significant reduction in 3-year morality in patients with LVEF ≤ 26% (33.8 vs. 44.3%, P < 0.001; adjusted HR 0.79, 95% CI 0.64-0.97, P = 0.023), but not in patients with LVEF > 26%. Conclusions: Although spironolactone was frequently used at lower doses in real-world practice, use of spironolactone significantly reduced 3-year mortality in patients with severely reduced LVEF with acceptable safety profile. However, our findings remain prone to various biases and further prospective randomized controlled studies are needed to confirm these findings.

Urban soils research: SUITMA 10.

Research on Soils in Urban, Industrial, Traffic, Mining and Military Areas (SUITMA) has been presented at biennial SUITMA conferences held in cities around the world. Soils from these areas often present environmental, ecological, and health risks and can limit ecological functions and ecosystem services. However, as with all soils, they are an integral part of the local ecosystem. In urban areas in particular, soil is a critical resource and can play a key role in the long-term sustainability and resiliency of cities. This special section contains five papers from the SUITMA 10 conference held in Seoul, South Korea, in 2019. They cover diverse topics that include urban soil properties, risk from contaminated soils, biological indicators for ecological functions, air deposition in urban gardens, and international summer field school opportunities. This section highlights research on anthropogenic soils conducted by the SUITMA community to promote better understanding and management of these soils.

J-curve relationship between corrected QT interval and mortality in acute heart failure patients.

BACKGROUND/AIMS: This study investigated the prognostic power of corrected QT (QTc) interval in patients with acute heart failure (AHF) according to sex. METHODS: We analyzed multicenter Korean Acute Heart Failure registry with patients with AHF admitted from 2011 to 2014. Among them, we analyzed 4,990 patients who were followed up to 5 years. Regarding QTc interval based on 12 lead electrocardiogram, patients were classified into quartiles according to sex. RESULTS: During follow-up with median 43.7 months, 2,243 (44.9%) patients died. The relationship between corrected QT interval and all-cause mortality followed a J-curve relationship. In Kaplan-Meier analysis, both sex had lowest mortality in the second QTc quartile. There were significant prognostic differences between the second and the fourth quartiles in male (log-rank p = 0.002), but not in female (log-rank p = 0.338). After adjusting covariates, the third (hazard ratio [HR], 1.185; 95% confidence interval [CI], 1.001 to 1.404; p = 0.049) and the fourth (HR, 1.404; 95% CI, 1.091 to 1.535; p = 0.003) quartiles demonstrated increased risk of mortality compared to the second quartile in male. In female, however, there was no significant difference across quartiles. QTc interval was associated with 5-year all-cause mortality in J-shape with nadir of 440 to 450 ms in male and 470 to 480 ms in female. CONCLUSION: QTc interval was an independent predictor of overall death in male, but its significance decreased in female. The relationship between QTc interval and all-cause mortality was J-shaped in both sex.

Efficacy and Tolerability of Telmisartan/Amlodipine and Rosuvastatin Coadministration in Hypertensive Patients with Hyperlipidemia: A Phase III, Multicenter, Randomized, Double-blind Study.

PURPOSE: Dyslipidemia and hypertension increase the risk for cardiovascular disease. Combination therapy improves patient compliance. This study was conducted to compare the efficacy and tolerability of the combination therapies telmisartan/amlodipine + rosuvastatin, telmisartan/amlodipine, and telmisartan + rosuvastatin in patients with hypercholesterolemia and hypertension. METHODS: In this Phase III, multicenter, 8-week randomized, double-blind study, participants with hypertension and dyslipidemia (defined as a sitting systolic blood pressure [sitSBP] of ≥140 mm Hg, a low-density lipoprotein-cholesterol [LDL-C] level of ≤250 mg/dL, and a triglyceride level of ≤400 mg/dL) were screened. After a 4-week washout/run-in period involving therapeutic lifestyle changes and telmisartan 80 mg once a day, eligible patients had a sitSBP of ≥140 mm Hg and met the LDL-C level criteria according to the National Cholesterol Education Program Adult Treatment Panel III cardiovascular disease risk category. Patients were randomly assigned to 1 of 3 groups: (1) telmisartan/amlodipine 80/10 mg + rosuvastatin 20 mg (TAR group); (2) telmisartan/amlodipine 80/10 mg (TA group); or (3) telmisartan 80 mg + rosuvastatin 20 mg (TR group). The primary efficacy end points were the percentage changes from baseline in LDL-C in the TAR and TA groups and the mean changes in sitSBP in the TAR and TR groups at week 8 compared to baseline. Continuous variables were compared using the unpaired t test or the Wilcoxon rank sum model, and categorical variables were compared using the χ2 or Fisher exact test. Tolerability was assessed based on adverse events found on physical examination including vital sign measurements, laboratory evaluations, and 12-lead ECG. FINDINGS: A total of 134 patients were enrolled. The least squares mean percentage changes in LDL-C at 8 weeks after administration of the drug compared to baseline were -51.9% (3.0%) in the TAR group and -3.2% (2.9%) in the TA group (P < 0.001). At 8 weeks after baseline, the least squares mean (SE) changes sitSBP were -28.3 (2.4) mm Hg in the TAR group and -10.7 (2.1) mm Hg in the TR group (P < 0.001). The prevalence rates of treatment-emergent adverse events were 15.0%, 25.0%, and 12.2% in the TAR, TA, and TR groups, respectively; those of adverse drug reactions were 15.0%, 22.7%, and 10.2%. None of the differences in rates were significant among 3 groups. IMPLICATIONS: Triple therapy with TAR can be an effective treatment in patients with dyslipidemia and hypertension. The TAR combination has value for hypertensive patients with hyperlipidemia in terms of convenience, tolerability, and efficacy. ClinicalTrials.gov identifier: NCT03566316.

Outcomes After Predischarge Initiation of ß-Blocker in Patients Hospitalized for Severe Decompensated Heart Failure Requiring Inotropic Therapy.

BACKGROUND: The optimal time for initiating ß-blocker (BB) treatment in patients with severe acute decompensated heart failure requiring inotropic therapy has not been well defined. We evaluated the effect of predischarge initiation of BB treatment on clinical outcomes. METHODS: Among the 5625 patients enrolled in the Korean Acute Heart Failure (KorAHF) registry, 672 BB-naive patients suffering from heart failure with reduced ejection fraction (median, 67.0 years; 62.5% male; median left ventricular ejection fraction, 24.1%) who received inotropic support during hospitalization were evaluated. We compared the risk of post-discharge mortality and rehospitalization between groups with (n = 282) and without (n = 390) pre-discharge BB treatment. RESULTS: During a median follow-up of 2.6 years, all-cause mortality occurred in 252 patients (37.5%). Those who received pre-discharge BB treatment showed lower 2-year mortality rates compared with those who did not (21.3% vs 39.3%; P < 0.001). In a Cox proportional hazards model, all-cause mortality was consistently lower in pre-discharge BB groups after multivariable adjustment (hazard ratio, 0.69; 95% confidence interval, 0.50-0.95; P = 0.025) and adjustment for propensity score methods using the inverse probability of treatment weighting (hazard ratio, 0.70; 95% confidence interval, 0.52-0.93; P = 0.016). The same trend was observed for secondary outcomes of rehospitalization for any cause and rehospitalization for heart failure. Pre-discharge BB was associated with higher rates of BB prescription after 6 (90.1% vs 23.9%; P < 0.001) and 12 (88.9% vs 25.0%; P < 0.001) months. CONCLUSIONS: Pre-discharge BB initiation is associated with better clinical outcomes after severe acute decompensated heart failure episodes requiring inotropic therapy.

Correction to: Determining soil quality in urban agricultural regions by soil enzyme-based index.

Unfortunately, in the original publication of the article, Prof. Yang Sik Ok's affiliation was incorrectly published. The author's affiliation is as follows.

Determining soil quality in urban agricultural regions by soil enzyme-based index.

Urban agricultural soils are highly variable, and careful selection of sensitive indicators is needed for the assessment of soil quality. This study is proposed to develop an index based on soil enzyme activities for assessing the quality of urban agricultural soils. Top soils were collected from urban agricultural areas of Korea, and soil chemical properties, texture, microbial fatty acids, and enzyme activities were determined. The soils belonged to five textural classes with the highest frequency of sandy loam. There was no clear correlation between the soil chemical properties and soil microbial properties. Principal component analysis (PCA) and factor analysis were applied to microbial groups for identification of microbial community variation in soils. Two soil groups, namely group 1 (G1) and group 2 (G2), based on microbial community abundance were examined by PCA, and those were more prominent in factor analysis. The G1 soils showed higher microbial community abundance than G2 soils. The canonical discriminant analysis was applied to the enzyme activities of sandy loam soil to develop an index, and the index validation was confirmed using the unused soils and published data. The high-quality soils in published literature assigned the high valued index. Microbial fatty acids and soil enzyme activities can be suitable indicators for soil quality evaluation of urban agricultural soils.

Influence of Road Proximity on the Concentrations of Heavy Metals in Korean Urban Agricultural Soils and Crops.

The urban agricultural (UA) environment near active roadways can be degraded by traffic-related particles (i.e., exhaust gases and road dust), which may contain heavy metals. The current study investigated changes in heavy-metal [cadmium (Cd), copper (Cu), chromium (Cr) nickel (Ni), lead (Pb) and zinc (Zn)] concentrations in soils located near highly trafficked roads in Korea and the subsequent uptake of these metals by Chinese cabbage. Heavy-metal plant concentrations were determined in both washed and unwashed plant leaves to determine whether foliar deposition played any role in plant metal uptake. Soil concentrations of Cd, Cu, Pb, and Zn were all lower than the Korean standard soil limits and showed no significant influence from road traffic. In contrast, both Ni and Cr concentrations in soils collected within 10 m of the road were 4 and 5 times greater, respectively, than those in soils collected 70 m from the road. Heavy-metal concentrations in unwashed Chinese cabbage leaf collected at 5 m from the road were consistently greater than those of washed leaf samples, thus indicating the deposition of traffic-related particles on the plant surface. With the exception of Cu, all heavy-metal concentration in washed plant samples collected at 5 m also showed greater accumulation compared with samples collected further away. This was mainly attributed to increased total soil heavy-metal concentrations and increased metal phytoavailability induced by decreases in soil pH near the road. However, overall heavy-metal soil concentrations were well lower than the allowable concentrations, and the levels observed in plants collected in this study were considered not to currently pose a significant risk to human health. However, some traffic-related heavy metals, in particular Cr and Ni, were being accumulated in the roadside UA environment, which may warrant some caution regarding the environment and/or health issues in the future.

Effect of biochar on reclaimed tidal land soil properties and maize (Zea mays L.) response.

Reclaimed tidal land soil (RTLS) often contains high levels of soluble salts and exchangeable Na that can adversely affect plant growth. The current study examined the effect of biochar on the physicochemical properties of RTLS and subsequently the influence on plant growth performance. Rice hull derived biochar (BC) was applied to RTLS at three different rates (1%, 2%, and 5% (w/w)) and maize (Zea mays L.) subsequently cultivated for 6weeks. While maize was cultivated, 0.1% NaCl solution was supplied from the bottom of the pots to simulate the natural RTLS conditions. Biochar induced changes in soil properties were evaluated by the water stable aggregate (WSA) percentage, exchangeable sodium percentage (ESP), soil organic carbon contents, cation exchange capacity, and exchangeable cations. Plant response was measured by growth rate, nutrient contents, and antioxidant enzyme activity of ascorbate peroxidase (APX) and glutathione reductase (GR). Application of rice hull derived biochar increased the soil organic carbon content and the percentage of WSA by 36-69%, while decreasing the ESP. The highest dry weight maize yield was observed from soil which received 5% BC (w/w), which was attributed to increased stability of water-stable aggregates and elevated levels of phosphate in BC incorporated soils. Moreover, increased potassium, sourced from the BC, induced mitigation of Na uptake by maize and consequently, reduced the impact of salt stress as evidenced by overall declines in the antioxidant activities of APX and GR.

Sorption and transport of sulfamethazine in agricultural soils amended with invasive-plant-derived biochar.

Sulfonamides (SAs) are one of the most frequently used antibiotics in the veterinary industry, showing high mobility in soils. Objectives of this research were to determine the sorption, distribution coefficients and involvement of different ionic forms of sulfamethazine (SMZ), a representative SAs, and to evaluate the transport of SMZ in biochar treated soils. Biochars were produced from an invasive plant, burcucumber (Sicyos angulatus L.), under slow pyrolysis conditions at peak temperatures of 300 °C (biochar-300) and 700 °C (biochar-700), respectively. The abilities of the biochars to retain SMZ in loamy sand and sandy loam soils were examined under different pHs and SMZ loadings. Soil column experiments were performed with and without biochars addition. Results showed that biochar-700 had a high degree of SMZ retention, with resultant decreased pH in both soils. Modeled effective sorption coefficients (KD,eff) values indicated that the observed high SMZ retention at pH 3 could be attributed to the π-π electron donor-acceptor interaction and electrostatic cation exchange, whereas at pH 5 and 7, cation exchange was the main mechanisms responsible. There was no temporal retardation of SMZ in biochar treated soil as compared to the untreated soil. However, biochar-700 treatment achieved up to 89% and 82% increase in the SMZ retention in sandy loam and loamy sand soils, respectively. The overall results demonstrated that burcucumber biochar produced at higher temperature was effective in reducing the mobility of SMZ in the studied soils.

Cadmium resistance in tobacco plants expressing the MuSI gene.

MuSI, a gene that corresponds to a domain that contains the rubber elongation factor (REF), is highly homologous to many stress-related proteins in plants. Since MuSI is up-regulated in the roots of plants treated with cadmium or copper, the involvement of MuSI in cadmium tolerance was investigated in this study. Escherichia coli cells overexpressing MuSI were more resistant to Cd than wild-type cells transfected with vector alone. MuSI transgenic plants were also more resistant to Cd. MuSI transgenic tobacco plants absorbed less Cd than wild-type plants. Cd translocation from roots to shoots was reduced in the transgenic plants, thereby avoiding Cd toxicity. The number of short trichomes in the leaves of wild-type tobacco plants was increased by Cd treatment, while this was unchanged in MuSI transgenic tobacco. These results suggest that MuSI transgenic tobacco plants have enhanced tolerance to Cd via reduced Cd uptake and/or increased Cd immobilization in the roots, resulting in less Cd translocation to the shoots.

Fugacity modelling to predict the distribution of organic contaminants in the soil:oil matrix of constructed biopiles.

Level I and II fugacity approaches were used to model the environmental distribution of benzene, anthracene, phenanthrene, 1-methylphenanthrene and benzo[a]pyrene in a four phase biopile system, accounting for air, water, mineral soil and non-aqueous phase liquid (oil) phase. The non-aqueous phase liquid (NAPL) and soil phases were the dominant partition media for the contaminants in each biopile and the contaminants differed markedly in their individual fugacities. Comparison of three soils with different percentage of organic carbon (% org C) showed that the % org C influenced contaminant partitioning behaviour. While benzene showed an aqueous concentration worthy of note for leachate control during biopiling, other organic chemicals showed that insignificant amount of chemicals leached into the water, greatly reducing the potential extent of groundwater contamination. Level II fugacity model showed that degradation was the dominant removal process except for benzene. In all three biopile systems, the rate of degradation of benzo(a)pyrene was low, requiring more than 12 years for soil concentrations from a spill of about 25 kg (100 mol) to be reduced to a concentration of 0.001 microgg(-1). The removal time of 1-methylphenanthrene and either anthracene or phenanthrene was about 1 and 3 years, respectively. In contrast, benzene showed the highest degradation rate and was removed after 136 days in all biopile systems. Overall, this study confirms the association of risk critical contaminants with the residual saturation in treated soils and reinforces the importance of accounting for the partitioning behaviour of both NAPL and soil phases during the risk assessment of oil-contaminated sites.

Impact of preinterventional arterial remodeling on in-stent neointimal hyperplasia and in-stent restenosis after coronary stent implantation.

BACKGROUND: Patterns of arterial remodeling during the course of plaque development have been shown to play an important role in both the progression of de novo atherosclerosis and in the restenotic process following coronary intervention. The aim of the present prospective study was to evaluate the effect of pre-interventional arterial remodeling on in-stent neointimal hyperplasia (NIH) and in-stent restenosis (ISR) after stenting. METHODS AND RESULTS: Pre-interventional arterial remodeling was assessed in 85 native coronary lesions by using intravascular ultrasound (IVUS). The remodeling index (RI) was 1.09+/-0.20 in the positive remodeling (PR)/intermediate remodeling (IR) group and 0.84+/-0.12 in the negative remodeling (NR) group. The plaque plus media cross sectional area (P&M CSA) at pre-intervention and NIH CSA at follow-up in the minimal lumen CSA were significantly larger in the PR/IR group (9.2+/-2.9 mm2 vs 6.2+/-1.8 mm2, 3.3+/-1.2 mm2 vs 1.5+/-0.9 mm2; p = 0.001, p = 0.001, respectively). On 3-dimensional analysis of IVUS images at follow-up, the lumen volume was significantly smaller in the PR/IR group than that in the NR group (62+/-15 mm3 vs 75 +/-20 mm3; p = 0.001), and neointima hyperplasia volume was significantly larger in the PR/IR group than that in the NR group (46+/-15 mm3 vs 26+/-10 mm3; p = 0.001). A significant positive correlation was found between pre-interventional RI and follow-up NIH CSA (r = 0.25, p = 0.022). The incidence of ISR and repeat intervention was significantly higher in the PR/IR group (30.8% vs 18.2%, 28.8% vs 15.2%; p = 0.032, 0.035, respectively). CONCLUSION: Measuring pre-interventional arterial remodeling patterns by IVUS may be helpful to stratify lesions at high-risk of ISR.