Rapid sand filtration for <10 μm-sized microplastic removal in tap water treatment: Efficiency and adsorption mechanisms

The omnipresence of microplastics (MPs) in potable water has become a major concern due to their potential disruptive effect on human health. Therefore, the effective removal of MPs in drinking water is essential for life preservation. In this study, tap water containing microplastic <10 μm in size was treated using constructed pilot-scale rapid sand filtration (RSF) system to investigate the removal efficiency and the mechanisms involved. The results show that the RSF provides significant capacity for the removal and immobilization of MPs < 10 μm diameter (achieving 98 %). Results showed that silicate sand reacted with MPs through a cooperative assembly process, which mainly involved interception, trapping, entanglement, and adsorption. The MPs were quantified by Flow cytometry instrument. A kinetics study underlined the pivotal role of physio-chemisorption in the removal process. MP particles smaller than absorbents, saturation of adsorbents, and reactor hydrodynamics were identified as limiting factors, which were alleviated by backwashing. Backwashing promoted the desorption of up to 97 % MPs, conducive for adsorbent active site regeneration. These findings revealed the critical role of RSF and the importance of backwashing in removing MPs. Understanding the mechanisms involved in removing microplastics from drinking water is crucial in developing more efficient strategies to eliminate them.

Development, validation, and application of a microbial community-based index of biotic integrity for assessing the ecological status of a peri-urban watershed in China

This study represents the pioneering effort in employing 16S rRNA-bacteria and 18S rRNA-microeukaryotes to construct the microbial community-based index of biotic integrity (MC-IBI) for assessing the ecological health of riverine ecosystems. The MC-IBI was developed, validated, and implemented using water samples from the Changle River watershed, encompassing both wet and dry seasons. A total of 205 metrics, containing microbial diversity, composition, pollution tolerance/sensitivity, and functional categories, were selected as candidates for evaluation. Following a rigorous screening process, five core metrics were identified as key indicators, namely Pielou's evenness of microeukaryotes, %Cryptophyceae, %Proteobacteria, %Oxyphotobacteria, and % 16S rRNA gene-human pathogens. Moreover, redundancy analysis revealed three metrics (i.e., Pielou's evenness, % 16S rRNA gene-human pathogens, and % Proteobacteria) were positively correlated with impairment conditions. In contrast, two metrics (i.e., %Oxyphotobacteria and %Cryptophyceae) were associated positively with reference conditions. Notably, the developed MC-IBI demonstrates clear discrimination between reference and impaired sites and significantly correlates with environmental parameters and land use patterns. A path model analysis revealed that land use patterns (i.e., build-up land, cropland) negatively impacted the MC-IBI scores. The application of the MC-IBI method yielded an assessment of the ecological conditions at the 73 sampling locations within the Changle River watershed, assigning them into categories of "Very good" (4.1 %), "Good" (4.1 %), "Moderate" (5.5 %), "Poor" (21.9 %), and "Very poor" (64.4 %). This bioassessment framework presents an innovative approach toward the preservation, maintenance, and management of riverine ecosystems.

Mass-immigration shapes the antibiotic resistome of wastewater treatment plants

Wastewater treatment plants (WWTPs) are the hotspots for the spread of antibiotic resistance genes (ARGs) into the environment. Nevertheless, a comprehensive assessment of the city-level and short-term daily (inter-day) variations of ARG profiles in the whole process (influent-INF, activated sludge-AS and effluent-EF) of WWTPs is still lacking. Here, 285 ARGs and ten mobile gene elements were monitored in seven WWTPs in Xiamen for seven days via high-throughput qPCR. The average daily load of ARGs to WWTPs was about 1.32 × 1020 copies/d, and a total of 1.56 × 1018 copies/d was discharged to the environment across the entire city. Stochastic processes were the main force determining the assembly of ARG communities during sampling campaign, with their relative importance ranked in the order of INF > EFF > AS. There're little daily variations in ARG richness, abundance, β-diversity composition as well as assembly mechanisms. The results of SourceTracker, variation partitioning analysis, and hierarchical partitioning analysis indicated that bacteria and ARGs from upstream treatment processes played an increasingly dominant role in shaping ARG communities in AS and EFF, respectively, suggesting the importance of mass-immigration of bacteria and ARGs from the source on ARG transport in wastewater treatment processes. This emphasizes the need to revise the way we mitigate ARG contamination but focus on the source of ARGs in urban wastewater.

Fate of Cryptosporidium and Giardia through conventional and compact drinking water treatment plants

Over the past three decades, a notable rise in the occurrence of enteric protozoan pathogens, especially Giardia and Cryptosporidium spp., in drinking water sources has been observed. This rise could be attributed not only to an actual increase in water contamination but also to improvements in detection methods. These waterborne pathogens have played a pivotal role in disease outbreaks and the overall escalation of disease rates in both developed and developing nations worldwide. Consequently, the control of waterborne diseases has become a vital component of public health policies and a primary objective of drinking water treatment plants (DWTPs). Limited studies applied real-time PCR (qPCR) and/or immunofluorescence assay (IFA) for monitoring Giardia and Cryptosporidium spp., particularly in developing countries like Egypt. Water samples from two conventional drinking water treatment plants and two compact units (CUs) were analyzed using both IFA and qPCR methods to detect Giardia and Cryptosporidium. Using qPCR and IFA, the conventional DWTPs showed complete removal of Giardia and Cryptosporidium, whereas Mansheyat Alqanater and Niklah CUs achieved only partial removal. Specifically, Cryptosporidium gene copies removal rates were 33.33% and 60% for Mansheyat Alqanater and Niklah CUs, respectively. Niklah CU also removed 50% of Giardia gene copies, but no Giardia gene copies were removed by Mansheyat Alqanater CU. Using IFA, both Mansheyat Alqanater and Niklah CUs showed a similar removal rate of 50% for Giardia cysts. Additionally, Niklah CU achieved a 50% removal of Cryptosporidium oocysts, whereas Mansheyat Alqanater CU did not show any removal of Cryptosporidium oocysts. Conventional DWTPs were more effective than CUs in removing enteric protozoa. The contamination of drinking water by enteric pathogenic protozoa remains a significant issue globally, leading to increased disease rates. Infectious disease surveillance in drinking water is an important epidemiological tool to monitor the health of a population.

PacBio next-generation sequencing uncovers Apicomplexa diversity in different habitats

The phylum Apicomplexa comprises a large group of intracellular protozoan parasites. These microorganisms are known to infect a variety of vertebrate and invertebrate hosts, leading to significant medical and veterinary conditions such as toxoplasmosis, cryptosporidiosis, theileriosis, and eimeriosis. Despite their importance, comprehensive data on their diversity and distribution, especially in riverine environments, remain scant. To bridge this knowledge gap, we utilized next-generation high-throughput 18S rRNA amplicon sequencing powered by PacBio technology to explore the diversity and composition of the Apicomplexa taxa. Principal component analysis (PCA) and principal coordinate analysis (PCoA) indicated the habitat heterogeneity for the physicochemical parameters and the Apicomplexa community. These results were supported by PERMANOVA (P < 0.001), ANOSIM (P < 0.001), Cluster analysis, and Venn diagram. Dominant genera of Apicomplexa in inlet samples included Gregarina (38.54%), Cryptosporidium (32.29%), and Leidyana (11.90%). In contrast, outlet samples were dominated by Babesia, Cryptosporidium, and Theileria. While surface water samples revealed 16% and 8.33% relative abundance of Toxoplasma and Cryptosporidium, respectively. To our knowledge, the next-generation high throughput sequencing covered a wide range of parasites in Egypt for the first time, which could be useful for legislation of the standards for drinking water and wastewater reuse.

Storm promotes the dissemination of antibiotic resistome in an urban lagoon through enhancing bio-interactions

Antibiotic-resistance genes (ARGs) and resistant bacteria (ARB) are abundant in stormwater that could cause serious infections, posing a potential threat to public health. However, there is no inference about how stormwater contributes to ARG profiles as well as the dynamic interplay between ARGs and bacteria via vertical gene transfer (VGT) or horizontal gene transfer (HGT) in urban water ecosystems. In this study, the distribution of ARGs, their host communities, and the source and community assembly process of ARGs were investigated in Yundang Lagoon (China) via high-throughput quantitative PCR, 16S rRNA gene amplicon sequencing, and application of SourceTracker before, after and recovering from an extreme precipitation event (132.1 mm). The abundance of ARGs and mobile genetic elements (MGEs) was the highest one day after precipitation and then decreased 2 days after precipitation and so on. Based on SourceTracker and NMDS analysis, the ARG and bacterial communities in lagoon surface water from one day after precipitation were mainly contributed by the wastewater treatment plant (WWTP) influent and effluent. However, the contribution of WWTP to ARG communities was minor 11 days after the precipitation, suggesting that the storm promoted the ARG levels by introducing the input of ARGs, MGEs, and ARB from point and non-point sources, such as sewer overflow and land-applied manure. Based on a novel microbial network analysis framework, the contribution of positive biological interactions between ARGs and MGEs or bacteria was the highest one day after precipitation, indicating a promoted VGT and HGT for ARG dissemination. The microbial networks deconstructed 11 days after precipitation, suggesting the stormwater practices (e.g., tide gate opening, diversion channels, and pumping) alleviated the spread of ARGs. These results advanced our understanding of the distribution and transport of ARGs associated with their source in urban stormwater runoff.

Domestic wastewater causes nitrate pollution in an agricultural watershed, China

Excessive quantities of nitrates in the aquatic environment can cause eutrophication and raise water safety concerns. Therefore, identification of the sources of nitrate is crucial to mitigate nitrate pollution and for better management of the water resources. Here, the spatiotemporal variations and sources of nitrate were investigated by stable isotopes (δ¹⁵N and δ¹⁸O), hydrogeochemical variables (e.g., NO₃^- and Cl^-), and exogenous microbial signals (i.e., sediments, soils, domestic and swine sewage) in an agricultural watershed (Changle River watershed) in China. The concentration ranges of δ¹⁵N- and δ¹⁸O-NO₃^- between 3.03‰-18.97‰ and -1.55‰-16.47‰, respectively, suggested that soil nitrogen, chemical fertilizers, and manure and sewage (M&S) were the primary nitrate sources. Bayesian isotopic mixing model suggested that the major proportion of nitrate within the watershed (53.12 ± 10.40% and 63.81 ± 15.08%) and tributaries (64.43 ± 5.03% and 76.20 ± 4.34%) were contributed by M&S in dry and wet seasons, respectively. Community-based microbial source tracking (MST) showed that untreated and treated domestic wastewater was the major source (>70%) of river microbiota. Redundancy analysis with the incorporation of land use, hydrogeochemical variables, dual stable isotope, and exogenous microbial signals revealed domestic wastewater as the dominant cause of nitrate pollution. Altogether, this study not only identifies and quantifies the spatiotemporal variations in nitrate sources in the study area but also provides a new analytical framework by combining nitrate isotopic signatures and community-based MST approaches for source appointment of nitrate in other polluted watersheds.

Tracking microeukaryotic footprint in a peri-urban watershed, China through machine-learning approaches

Microeukaryotes play a significant role in biogeochemical cycling and can serve as bioindicators of water quality in freshwater ecosystems. However, there is a knowledge gap on how freshwater microeukaryotic communities are assembled, especially that how terrestrial microeukaryotes influence freshwater microeukaryotic assemblages. Here, we used a combination of 18S rRNA gene amplicon sequencing and community-based microbial source tracking (MST) approaches (i.e., SourceTracker and FEAST) to assess the contribution of microeukaryotes from surrounding environments (i.e., soils, river sediments, swine wastewater, influents and effluents of decentralized wastewater treatment plants) to planktonic microeukaryotes in the main channel, tributaries and reservoir of a peri-urban watershed, China in wet and dry seasons. The results indicated that SAR (~ 49% of the total communities), Opithokonta (~ 34%), Archaeplastida (~ 9%), and Amoebozoa (~ 2%) were dominant taxa in the watershed. The community-based MST analysis revealed that sewage effluents (7.96 - 21.84%), influents (2.23 - 13.97%), and river sediments (2.56 - 11.71%) were the major exogenous sources of riverine microeukaryotes. At the spatial scale, the downstream of the watershed (i.e., main channel and tributaries) received higher proportions of exogenous microeukaryotic OTUs compared to the upstream reservoirs, while at the seasonal scale, the sewage effluents and influents contributed higher exogenous microeukaryotes to river water in wet season than in dry season. Moreover, the swine and domestic wastewater led to the presence of Apicomplexa in wet season only, implying rainfall runoff may enhance the spread of parasitic microeukaryotes. Taken together, our study provides novel insights into the immigration patterns of microeukaryotes and their dominant supergroups between terrestrial and riverine habitats.

Outcomes of transfemoral-transcatheter aortic valve replacement with Sapien-3 valve in liver cirrhosis patients

Background

Little is known about the outcomes of liver cirrhosis patients with severe aortic stenosis (AS) who undergo transcatheter aortic valve replacement (TAVR).

Methods

We undertook a retrospective analysis of consecutive patients with severe symptomatic AS who underwent transfemoral-TAVR with Sapien-3 valve at our Clinic between April 2015 and December 2018, yielding 32 patients with liver cirrhosis on imaging including ultrasound and/or computed tomography. Their baseline characteristics, procedural and long-term outcomes after TAVR with the non-cirrhotic group were compared, along with their management strategies as per the hepatology team.

Results

Among 1028 patients, 32 were assigned to the cirrhosis, and 996 were assigned to the non-cirrhosis (control) group. Compared with the control group cirrhotic patients were slightly younger in age (74.5 vs 81.2 years), had a slightly higher BMI (31.3 vs 29.3), and had a higher incidence of prior history of myocardial infarction (38% vs 33%). Baseline variables including the history of smoking, hypertension, diabetes, and atrial fibrillation were comparable in both groups. Among cirrhotic patients (n=32), the most common etiologies were non-alcoholic steatohepatitis (NASH) (37.5%), Alcoholism (18.75%), and Hepatitis C (12.5%). The mean MELD-NA score was 11.8 and 67% of patients were Child PUGH Class A and 33% were Child PUGH Class B and all patients had a Child PUGH score of ≥5. 53% of patients (n=17) in the cirrhosis group were evaluated by Hepatology and 12.5% (n=4) were evaluated for a liver transplant but only 1 patient had a liver transplant post-TAVR. Compared with the control group cirrhotic patients had similar 1-year mortality (12% vs 12%, p=1), had a lower rate of 30-day new pacemaker post tavr (6% vs 9% p=0.85), had a higher rate of 1-year readmission for heart failure (12% vs 5% p=0.12) and similar 1-year major adverse cardiac and cerebrovascular event (MACCE) rate (15% vs 14% p=0.98)

Conclusion

Patients with severe AS undergoing TAVR with concomitant liver cirrhosis demonstrate comparable outcomes compared with their non- cirrhotic counterparts. NASH followed by alcoholic cirrhosis was found to be most common etiology.

Funding Acknowledgement

Type of funding sources: None. Figure 1Figure 2

Fecal pollution mediates the dominance of stochastic assembly of antibiotic resistome in an urban lagoon (Yundang lagoon), China

Sewage and fecal pollution cause antibiotic resistance genes (ARGs) pollution in urban lagoons. Seasonality also affects ARG dynamics. However, knowledge of factors controlling ARG community assembly across seasons is still limited. Here, we revealed the seasonal variation of ARGs and depict the underlying assembly processes and drivers via high-throughput quantitative PCR in an urban lagoon, China. A higher richness and abundance of ARGs were observed in summer and winter compared to spring and fall (Kruskal-Wallis test, P < 0.05). Both ARG and prokaryotic communities were mainly governed by stochastic processes, however, these processes drove ARGs and prokaryotes differently across seasons. Stochastic processes played a more dominant role in shaping ARG communities in summer (average stochasticity: 83%) and winter (75%), resulting in a stable antibiotic resistome. However, no such seasonal pattern of stochastic processes was determined for prokaryotes, indicating a decoupling of the assembly process of ARGs and prokaryotes. Moreover, fecal microorganisms (e.g., Bacteroidetes and Faecalibacterium) mediated the stochastic processes of ARG profiles, via enhancement of prokaryotic biomass and mobile genetic element abundances. The tnpA-07 transposase was the key for the horizontal gene transfer. These findings will enhance our understanding of how fecal pollution shapes ARG community assembly in urban lagoons.

Integrated assessment of major and trace elements in surface and core sediments from an urban lagoon, China: Potential ecological risks and influencing factors

Marine sediments serve as a sink for contaminants of anthropogenic origin. Here, 25 major and trace elements were determined in surface and core sediments from an urban lagoon (Yundang Lagoon), China. The median concentrations of Pb, Cd, Cu, and Zn in both surface and core sediments exceeded global and crustal averages. Principal component analysis for the elements and ecological impact of the heavy metals indicated spatial heterogeneity in core sediments from different lagoon areas; however, no such pattern was observed in surface sediments. Geodetector analysis indicated spatial locations of lakes, pH, N%, C%, and S% as the major factors influencing the heterogeneity of potential ecological risk index, a cumulative measure of the ecological impact of heavy metal. The interaction detector indicated nonlinear and bivariate enhancement between different physicochemical parameters. Besides, a depth profile of the elements in different samples was also elucidated.

QTL Mapping for Seed Germination Response to Drought Stress in Brassica napus

Drought stress is one of the most environmental abiotic stresses affecting seed germination and crop growth. In the present study, the genetic characteristics of seed germination under drought stress in a Brassica napus double haploid population were analyzed. Five germination-related indexes, including germination percentage (GP), root length (RL), shoot length (SL), fresh weight (FW), and root-to-shoot length ratio (R/S) under control and drought stress, were calculated, and the drought stress index (DSI), including DSI-GP, DSI-RL, DSI-SL, DSI-FW, and DSI-R/S, was determined using the quantitative trait loci (QTLs) analysis based on high-density genetic linkage map. The phenotypic analysis indicated that the R/S is an effective morphological trait in the determination of drought tolerance in the seedling stage. Thirty-nine identified QTLs were observed for these traits and then integrated into 36 consensus QTLs, in which 18 QTLs were found to affect the DSI of four traits (GP, RL, SL, and R/S). Based on the co-linearity between genetic and physical maps of B. napus, 256 candidate genes were detected, and 128 genes have single-nucleotidepolymorphisms/insertion-deletion (SNP/InDel) variations between two parents, some of which were associated with the drought stress tolerance (for example, BnaC03g32780D, BnaC03g37030D, and BnaC09g27300D). The present results laid insights into drought tolerance and its genetic bases in B. napus.

Distinct mechanisms underlying the assembly of microeukaryotic generalists and specialists in an anthropogenically impacted river

Microeukaryotic communities are sensitive to environmental changes; and are considered essential for microbial food webs and biogeochemical cycles. Therefore, understanding the community responses of microeukaryotes to environmental changes is of great ecological significance. Very little is known about the assembly mechanisms underlying the microeukaryotic communities, especially for the key ecological groups (e.g., habitat generalists/specialists) in the riverine ecosystems. Here, we employed 18S rDNA amplicon sequencing to study the assembly processes governing the microeukaryotic communities and their habitat generalists and specialists across three hydrological seasons in a subtropical river in China. The results showed that deterministic and stochastic processes jointly shaped the microeukaryotic communities, where the relative importance of stochastic processes decreased in the following order: wet > normal > dry seasons. However, deterministic processes played more important role in shaping the microeukaryotic communities than those of prokaryotes. Meanwhile, stochastic and deterministic processes were responsible for structuring the microeukaryotic habitat generalists and specialists, respectively. Generally, the pure effects of physicochemical factors on the microeukaryotic communities and their key ecological groups were ~ 1.7 folds than those of the micropollutants. However, several micropollutants (e.g., acetaminophen, benzophenone-3, bisphenol A, sulfadiazine, triclocarban and triclosan) were found to have a strong effect on the habitat specialists. Altogether, we suggested that the ecological responses of the riverine microeukaryotes to micropollutants may vary among species due to the intrinsic differences in their environmental plasticity.

Microglial activation increases cocaine self-administration following adolescent nicotine exposure

With the rise of e-cigarette use, teen nicotine exposure is becoming more widespread. Findings from clinical and preclinical studies show that the adolescent brain is particularly sensitive to nicotine. Animal studies have demonstrated that adolescent nicotine exposure increases reinforcement for cocaine and other drugs. However, the mechanisms that underlie these behaviors are poorly understood. Here, we report reactive microglia are critical regulators of nicotine-induced increases in adolescent cocaine self-administration. Nicotine has dichotomous, age-dependent effects on microglial morphology and immune transcript profiles. A multistep signaling mechanism involving D2 receptors and CX3CL1 mediates nicotine-induced increases in cocaine self-administration and microglial activation. Moreover, nicotine depletes presynaptic markers in a manner that is microglia-, D2- and CX3CL1-dependent. Taken together, we demonstrate that adolescent microglia are uniquely susceptible to perturbations by nicotine, necessary for nicotine-induced increases in cocaine-seeking, and that D2 receptors and CX3CL1 play a mechanistic role in these phenomena.

Adolescents are particularly sensitive to nicotine. Here the authors show that in mice, microglial activation contributes to the enhanced sensitivity to cocaine caused by nicotine exposure in young mice.

Early Progressive Maxillary Changes with Nasoalveolar Molding: Randomized Controlled Clinical Trial

OBJECTIVES

Quantitative assessment of 3-dimensional progressive changes of the maxillary geometry in unilateral cleft lip palate (UCLP) with and without nasoalveolar molding (NAM).

METHODS

The study was designed as a prospective 2-arm randomized controlled clinical trial conducted in parallel. Forty infants with nonsyndromic UCLP were randomly assigned into a NAM-treated group (n = 20) and non-NAM treated group (n = 20). A total of 120 laser-scanned maxillary casts were collected and blindly analyzed via a modified algorithm at T0 (initial visit; baseline), T1 (after 3 wk; first interval), and T2 (after 6 wk; second interval). The main outcome measures were the amount and rate of cleft gap changes, the midline position, and the transverse, sagittal, and vertical growth through intervals.

RESULTS

More than 50% of the cleft gap (56.42%; P < 0.001) was reduced in the first 3 wk of alveolar molding (AM). The end point of the AM was obtained in 6 wk (86.25%; P < 0.001); then, the kinks of the greater segment were noticed. The AM effect decreased as far as posterior; the anterior arch width reduced slightly (1.23%; P < 0.001), while the middle and posterior arches increased slightly (P > 0.999 and P = 0.288, respectively). The posterior arch width was the least changing and was considered a baseline, while the anterior was the pivot of the segment rotation. Both groups showed different patterns of segment rotation and sagittal growth. The non-NAM treated group showed a slight increase in cleft gap length, arch width, and midline position.

CONCLUSION

Based on this study, it was concluded that the NAM treatment is effective in minimizing cleft severity and realigning maxillary segments without the deterioration of the transverse and vertical arch growth. Near follow-up visits are recommended to monitor the rapid gap reduction within the first 3 wk. Further trials are recommended to compare the outcomes regarding the sagittal growth to reference values (ClinicalTrials.gov NCT03029195).

KNOWLEDGE TRANSFER STATEMENT

The results of this study will help clinicians understand nasoalveolar molding biomechanics that may improve the treatment outcomes for patients with unilateral cleft lip and palate. The trial data can be a valuable guide to the qualitative and quantitative predictive virtual molding in computer aided design-simulated nasoalveolar molding therapy. The modified algorithm can be used by researchers to quantify the rate, the sequence, and the direction of the maxillary segments movement in unilateral cleft lip and palate.

P6438Trends of acute kidney injury following percutaneous coronary interventions

Introduction

Acute kidney injury (AKI) is a significant in-hospital complication in patients undergoing percutaneous coronary interventions (PCI) and has been shown to be associated with poor outcomes. Prior studies have shown an upward trend of AKI post PCI which may be related to a multitude of factors. In this study, we aim to discern whether the recent changes in AKI definition, awareness of risk calculators, and preventive measures have been effective in changing the inclining trend.

Methods

Patients who underwent PCI during hospitalization were identified retrospectively in the Nationwide Readmission Database (NRD) from January 2010 to December 2014. All patients older than 18 years were included in the current study. Patient demographics and comorbidities were identified using appropriate ICD-9 codes. The primary outcome is the temporal trends of AKI following PCI and secondary outcomes are temporal trends in mortality, length of stay and hospitalization cost in patients with AKI. Continuous variables were expressed as means ± standard deviation or median (IQR), and categorical variables were expressed as percentages (%). All statistical tests were two-sided.

Results

Among the 2,712,473 patients who underwent PCI from 2010 to 2014, 162,286 (6%) patients developed AKI post PCI. Mean age was 69.22±12.34 years and 65% of them were males. The percentage of cases with AKI rose almost twofold from 2010 to 2014 (4.8% to 8.1%, p-value <0.005), despite the lack of a significant change in patient's demographics and comorbidities over the years. Among patients with a history of Chronic Kidney Disease (CKD) the incidence of AKI increased from 20.3% to 24.2%, and in patients without CKD history the incidence of AKI almost doubled (2.6% to 5.0%) from 2010 to 2014. There was a slight decrease in in-hospital mortality (9.4% to 8.8%) and median length of stay (7 days to 5 days), and a slight increase in the mean cost of hospitalization ($124,755.1 to $133,902.17) from 2010 to 2014.

AKI Incidence and mortality trend

Conclusion

This large cohort study shows a consistent uptrend of AKI in patients undergoing PCI from 2010 to 2014. Despite this, the mortality and length of stay are decreasing while the cost of hospitalization only slightly increased in patients with AKI. Thus, future drives to implement renal protective measures and advanced studies to identify new preventive therapies are needed to reduce the incidence of AKI post-PCI.

P5331Aspirin use for prevention of cardiovascular events in patients with high lipoprotein(a): a population-based study

Background

High lipoprotein(a) [Lp(a)] levels have been shown to increase Myocardial Infarction (MI) and all-cause mortality. However, studies evaluating the optimal preventive measures for that subset of cardiac patients are scarce. This study aims to study the outcomes of aspirin use versus no aspirin for the prevention of all-cause mortality and myocardial infarction in patients with high Lp(a) levels.

Purpose

We sought to determine the effect of Aspirin in reducing the rate of MI and all-cause mortality among patients with high lipoprotein(a) [Lp(a) ≥50mg/dL]

Methods

Patients who attended the preventive cardiology clinic from 2005 to 2016 and included in the Preventive Cardiology Database were included in the current single-center, retrospective, observational cohort study that was conducted according to the guidelines of the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology Statement) checklist. The primary outcome was the incidence of myocardial infarction and the secondary outcome was all-cause mortality. Patients were excluded in cases of I) Lp(a)a <50mg/dL, II) history of malignancy, or III) being on anticoagulation/ dual antiplatelet therapy. The median duration of follow-up was 92 months from time of Lp(a) measurement to the last follow-up. Continuous variables were expressed as means ± standard deviation or median (IQR), and categorical variables were expressed as percentages (%). All statistical tests were two-sided. A propensity score-matched analysis was performed with 1:1 nearest match for Age, Gender, Race, Smoking status, BMI, Diabetes, Peripheral artery disease, Carotid artery disease, coronary artery disease, chronic kidney disease, Heart failure, Hypertension, Dyslipidemia, Stroke, family history of coronary artery disease, Lp (a), LDL, HDL, Triglycerides, glucose and total cholesterol.

Results

1,805 patients fulfilled the inclusion and exclusion criteria out of 7,410 patients initially identified with recorded Lp(a) levels in the Preventive Cardiology Database. Of these, 376 patients were taking aspirin, and 1429 patients were not receiving aspirin. After propensity score matching for different baseline characteristics and comorbidities as mentioned above, 316 patients were matched in each group. Patients who were on Aspirin had a significantly lower rate of MI events compared to patients who were not on aspirin (6.96% vs 12.02%, P=0.03) and a lower rate, however statistically non-significant, of all-cause mortality (2.84% vs 4.11%, P=0.385).

Conclusion

The use of aspirin in patients with elevated Lp(a) levels significantly lowers the rate of myocardial infarction events. Larger randomized clinical trials are warranted to evaluate the use of aspirin for primary and secondary prevention of major adverse cardiovascular events in patients with high Lp(a) levels.

P6525Impact of acute arrhythmias on in-hospital mortality in patients undergoing angioplasty

Introduction

Arrhythmia is one of the most common complications in patients undergoing percutaneous coronary interventions (PCI). Prior attempts to address these arrhythmias “aggressively” did not show improvement in survival. This study aims to investigate the impact of acute arrhythmias on in-hospital mortality in patients undergoing angioplasty in the United States.

Methods

Data about patients undergoing PCI between January 2010 and December 2014 on the Nationwide Readmission Database (NRD) was queried from the Healthcare Cost and Utilization Project (HCUP). All patients undergoing PCI were identified with the appropriate ICD-9 procedure codes. Binominal logistic regression testing was utilized to perform a multivariate analysis and different patient baseline characteristics were adjusted for including age, gender, LOS, diabetes mellitus, hypertension, renal failure, and cancer diagnosis. Odds Ratio (OR) of in-hospital mortality following acute arrhythmia were reported alongside 95% Confidence Intervals (CI).

Results

A total of 2,712,078 patients underwent PCI during hospitalization from January 2010 to December 2014. Out of those, 56,985 (2.1%) patients died while hospitalized. Most of the patients who died were older (mean age 70.73±12.9) and males (59.3%). After adjusting for age, female gender, hypertension, diabetes, heart failure, anemia, malignancy, psychiatric disorder, and longer length of stay; ventricular and supraventricular arrhythmias were found to be predictors of in-hospital mortality. Atrial fibrillation had an OR of 1.588 (95% CI: 1.551–1.626), ventricular tachycardia an OR of 2.191 (95% CI: 2.133–2.250), and ventricular fibrillation an OR of 4.143 (95% CI: 4.031–4.258).

Conclusions

Ventricular and supraventricular arrhythmias are independent predictors of in-hospital mortality following angioplasty. Further studies are warranted to evaluate the optimal management for patients with acute arrhythmia following PCI.

Analysis of miR-146a and miR-142-3p as Potential Markers of Freshly Isolated or In Vitro-Expanded Human Treg cells

Regulatory CD4⁺ T cells (Tregs) are pivotal for prevention of autoimmunity. The use of Tregs is therefore of increasing interest in in vitro drug screening assays as well as for a cytotherapy per se against autoimmune disorders. For both purposes, in vitro expansion of peripheral blood Tregs is necessary and there is an increasing need to identify novel markers that can discriminate natural thymic-derived Tregs (tTregs) from other T cell subsets, and ideally, such markers should be stably expressed during in vitro expansion procedures. We screened for novel miRNAs differentially expressed in tTregs and identified miR-146a and 142-3p as possible candidates. We analysed freshly isolated naïve and activated tTregs and non-Treg subsets after or prior to in vitro expansion. We observed a tTreg-specific profile of these miRNAs together with FOXP3 and Helios in freshly isolated tTregs, but observed a decline in the same markers in activated tTregs as opposed to naïve tTregs. In vitro-expanded Tregs could be identified based on FOXP3 expression, but with loss of a discriminate profile for miRNA candidates and a decline in FOXP3 when activated tTregs were expanded. Our data demonstrate miR-146a and 142-3p as potential miRNA markers for discrimination between non-Treg cells and tTregs, but these miRNAs are not stable markers for in vitro-expanded Treg cells. In addition, the loss of FOXP3 in expansion of activated tTregs has implication for in vitro use of this cell subset in immunopharmacological assays and cytotherapy as FOXP3 is pivotal for suppressive function.

Genome-wide gene expression profiling of SCID mice with T-cell-mediated Colitis

Inflammatory bowel disease (IBD) is a multifactorial disorder with an unknown aetiology. The aim of this study is to employ a murine model of IBD to identify pathways and genes, which may play a key role in the pathogenesis of IBD and could be important for discovery of new disease markers in human disease. Here, we have investigated severe combined immunodeficient (SCID) mice, which upon adoptive transfer with concanavalin A-activated CD4(+) T cells develop inflammation of the colon with predominance in rectum. Mice with increasing level of inflammation was studied. RNA from rectum of transplanted and non-transplanted SCID mice was investigated by a genome-wide gene expression analysis using the Affymetrix mouse expression array 430A (MOE430A) including 22,626 probe sets. A significant change in gene expression (P = 0.00001) is observed in 152 of the genes between the non-transplanted control mice and colitis mice, and among these genes there is an overrepresentation of genes involved in inflammatory processes. Some of the most significant genes showing higher expression encode S100A proteins and chemokines involved in trafficking of leucocytes in inflammatory areas. Classification by gene clustering based on the genes with the significantly altered gene expression corresponds to two different levels of inflammation as established by the histological scoring of the inflamed rectum. These data demonstrate that this SCID T-cell transfer model is a useful animal model for human IBD and can be used for suggesting candidate genes involved in the pathogenesis and for identifying new molecular markers of chronic inflammation in human IBD.

Tolerogenic dendritic cells pulsed with enterobacterial extract suppress development of colitis in the severe combined immunodeficiency transfer model

Immunomodulatory dendritic cells (DCs) that induce antigen-specific T-cell tolerance upon in vivo adoptive transfer are promising candidates for immunotherapy of autoimmune diseases. The feasibility of such a strategy has recently proved its efficacy in animal models of allotransplantation and experimental allergic encephalitis, but the effect in inflammatory bowel disease has not yet been demonstrated. In severe combined immunodeficient (SCID) mice, adoptively transferred CD4(+) CD25(-) T cells repopulate the lymphoid tissues and lead to development of chronic colitis characterized by CD4(+) T-cell proliferation against enterobacterial extract in vitro. In this model, we adoptively transferred in-vitro-generated bone-marrow-derived DCs exposed to interleukin-10 (IL-10) and an enterobacterial extract. We show that these cells are CD11c positive with intermediate expression of CD40, CD80 and CD86 and have a diminished secretion of IL-6, IL-12 p40/70, tumour necrosis factor-alpha and keratinocyte-derived chemokine (KC) compared to DCs treated with enterobacterial extract alone. In vivo, these cells prevented weight loss in SCID mice adoptively transferred with CD4(+) CD25(-) T cells, resulted in a lower histopathology colitis score and tended to result in higher serum levels of IL-1alpha, IL-10, IL-12, IL-13, IL-17, KC and monokine induced by interferon-gamma (MIG). These data underscore the potential of using immunomodulatory DCs to control inflammatory bowel disease and demonstrate its potential use in future human therapeutic settings.

Characterization of monocyte-derived dendritic cells maturated with IFN-alpha

Dendritic cells (DC) are promising candidates for cancer immunotherapy. These cells can be generated from peripheral blood monocytes cultured with granulocyte macrophage-colony stimulating factor (GM-CSF) and interleukin-4 (IL-4). In order to obtain full functional capacity, maturation is required, but the most potent reagents such as LPS or polyriboinosinic polyribocytidylic acid (Poly I:C) are not approved for clinical use. We tested the ability of type I interferon (IFN) to induce such maturation. We found that 24-h IFN-alpha co-culture of day 7 monocyte-derived DC generated with GM-CSF and IL-4 induces increased numbers of DC positive for CD54 and CD40 together with the co-stimulatory molecule CD80 but not the activation marker CD83. Also, IFN-alpha maturation leads to an increase in IP-10 and MCP-1 chemokine secretion, but only a minor increase in IL-12p40 secretion. In line with this, maturation with IFN-alpha has only a small effect on induction of autologous T-cell stimulatory capacity of the DC. However, an increase in DC allogeneic T-cell stimulatory capacity was observed. These data suggest that IFN-alpha has a potential as a maturation agent used in DC-based cancer vaccine trials, but not as a single reagent.

Regulatory T cells in experimental colitis

Induction and maintenance of peripheral tolerance are important mechanisms to maintain the balance of the immune system. Growing evidence indicates that dysregulation of mucosal T cell responses may lead to loss of tolerance to commensal flora and to the development of inflammatory bowel diseases (IBD). Many studies suggest that active suppression of enteroantigen reactive cells mediated by regulatory T cells contributes to the maintenance of natural intestinal immune homeostasis. The use of the multiple animal models has not only improved our understanding of IBD, but also contributed to new suggestions of treatment strategies involving the use of regulatory T cells. The present review summarizes our current knowledge of regulatory T cells and their involvement in experimental IBD. The well-characterized SCID T cell transfer model and the naturally occurring regulatory CD4+CD25+ T cells are highlighted.

Phenotypic and functional characterization of clinical grade dendritic cells generated from patients with advanced breast cancer for therapeutic vaccination

Dendritic cells (DC) are promising candidates for cancer immunotherapy. However, it is not known whether in vitro-generated monocyte-derived DC from cancer patients are altered compared with DC from healthy donors. In a clinical phase I/II study, monocyte-derived DC were generated in vitro utilizing granulocyte macrophage colony-stimulating factor and rh-interleukin-4 (IL-4) and used for cancer immunotherapy. In this study, we tested the effect of various maturation cocktails and performed a comparative evaluation of the DC phenotype and functional characteristics. Polyriboinosinic polyribocytidylic acid (Poly I:C) + tumour necrosis factor-alpha (TNF-alpha) induced significant IL-12 p70 secretion, which was increased after addition of a decoy IL-10 receptor. The lymph node homing chemokine receptor CCR-7 expression was induced by TNF-alpha + IL-1beta + IL-6 + prostaglandin E2 but was not induced by Poly I:C + TNF-alpha. In general, DC from patients had an intermediate maturity phenotype with a significantly higher expression of CD40 and CD54 compared with healthy donors. In vitro analyses showed an unimpaired capacity of the patient-derived DC for antigen-specific (cytomegalovirus, tetanus and keyhole limpet haemocyanin) T-cell stimulation, whereas the allostimulatory capacity of patient-derived DC was significantly decreased. These data suggest that patient-derived DC are more differentiated but are less sensitive to maturation-inducing agents than DC obtained from healthy individuals.

Method for patterning stretched DNA molecules on mica surfaces by soft lithography

Lambda DNA was stretched and patterned on mica surface using soft lithography. A highly diluted solution of amino propyl trimethoxy silane in hexane was deposited on a line patterned polydimethylsiloxane (PDMS) stamp. The functionalized stamp was then used to pick up DNA by molecular combing while the line patterns are parallel to the liquid surface. The stamp was then microcontact printed on freshly cleaved mica. We successfully obtained stretched DNA pattern on mica surface. DNA was found to be stretched in patterns perpendicular to those carved on the stamp. The stretched DNA population was large enough to be used for molecular biology mapping studies. Furthermore, the possibility of locating stretched DNA molecules in the desired position by stamping makes this method a good candidate for assembling non-semiconductor molecular devices.

Immunobiological effects of glucosamine in vitro

Glucosamine (GlcN) and N-acetyl-d-glucosamine (GlcNAc) were assayed in vitro for their effects on proliferation, cytotoxicity and cytokine secretion in primary and secondary mixed lymphocyte cultures (MLCs). In addition, we studied the effect of GlcN and GlcNAc on the proliferation of purified CD4+ T cells exposed to immobilized anti-CD3 antibody. The present data show that GlcN, but not GlcNAc, inhibits CD4+ T-cell proliferation, the generation of alloreactive cytotoxic T lymphocytes (CTLs) and the secretion of interferon-gamma (IFN-gamma) and interleukin-5 (IL-5) in primary MLC. In secondary T helper-2 (Th2)-polarized MLC, GlcN, but not GlcNAc, inhibits IL-4 and IL-5 secretion, whereas no effect was found on IFN-gamma secretion in Th1-polarized MLC. Dendritic cells treated with GlcN showed a 75-80% decreased capacity for antigen cross-presentation and allostimulation. In cellular bioassays, GlcN was shown to inhibit the stimulatory activity of IL-4 and IL-2, as well as the cytotoxic activity of tumour necrosis factor-alpha (TNF-alpha). In conclusion, GlcN suppresses unprimed T-cell responses by interfering with antigen-presenting cell functions and by a direct inhibitory effect on T-cell proliferation. In addition, GlcN inhibits the secretion of cytokines in antigen-stimulated unprimed T cells and primed Th2-polarized cells.

Method for stretching DNA molecules on mica surface in one direction for AFM imaging

An efficient method was developed to stretch DNA molecules on an atomically flat surface for AFM imaging. This method involves anchoring DNA molecules from their 5' ends to amino silanized mica surfaces. N-Succinimidyl6-[3'-(2-pyridyldithio) propionamido]hexanoate (LC-SPDP), a heterobifunctional cross-linker with a flexible spacer arm was used for this purpose. The immobilization process was carried out by introducing a thiol group to the 5' end of DNA by PCR. Thiolated molecules were then reacted with the cross linker to conjugate with its 2-pyridyl disulphide group via sulfhydryl exchange. The resulting complex was deposited on amino silanized mica where NHS-ester moiety of the cross linker reacted with the primary amino group on the surface. Samples were washed by a current of water and dried by an air jet in one direction parallel to the surface. DNA molecules were shown to be fully stretched in one direction on imaging them by AFM.

CD4+ T regulatory cells from the colonic lamina propria of normal mice inhibit proliferation of enterobacteria-reactive, disease-inducing Th1-cells from scid mice with colitis

Adoptive transfer of CD4+ T cells into scid mice leads to a chronic colitis in the recipients. The transferred CD4+ T cells accumulate in the intestinal lamina propria (LP), express an activated Th1 phenotype and proliferate vigorously when exposed ex vivo to enteric bacterial antigens. As LP CD4+ T cells from normal BALB/c mice do not respond to enteric bacterial antigens, we have investigated whether colonic LP-derived CD4+ T cells from normal mice suppress the antibacterial response of CD4+ T cells from scid mice with colitis. LP-derived CD4+ T cells cocultured with bone marrow-derived dendritic cells effectively suppress the antibacterial proliferative response of CD4+ T cells from scid mice with colitis. The majority of these LP T-reg cells display a nonactivated phenotype and suppression is independent of antigen exposure, is partly mediated by soluble factor(s) different from IL-10 and TGF-beta, and is not prevented by the addition of high doses of IL-2 to the assay culture. Functionally and phenotypically the T-reg cells of the present study differ from previously described subsets of T-reg cells. The presence of T cells with a regulatory potential in the normal colonic mucosa suggests a role for these cells in the maintenance of local immune homeostasis of the gut.

Patterning DNA on microm scale on mica

Double-stranded DNA molecules were patterned by selective adsorption to aminosilane patterns on mica surfaces. Line patterns with 10 microm spacing were made by photolithography and transferred to a polymer stamp. The stamp was then used for applying aminosilane molecules by microcontact-printing technique on mica substrates. We applied DNA in Tris-EDTA (TE) buffer solution on the patterned substrate, and incubated it for 5 min at room temperature. The sample was then rinsed with pure water, and dried with nitrogen gas. Tapping mode force microscopy showed that DNA was adsorbed selectively on the aminosilanized parts of the mica substrate. We also tried to bridge two aluminum electrodes with DNA using AC electrophoresis.

Method for orienting DNA molecules on mica surfaces in one direction for atomic force microscopy imaging

An efficient method was developed to stretch DNA molecules on an atomically flat surface for AFM imaging. This method involves anchoring DNA molecules from their 5' ends to amino silanized mica surfaces. N-Succinimidyl6-[3'-(2-pyridyldithio) propionamido]hexanoate (LC-SPDP), a heterobifunctional cross-linker with a flexible spacer arm was used for this purpose. Immobilization was carried out by introducing a thiol group to the 5' end of DNA by PCR. Thiolated molecules were then reacted with the cross linker to conjugate with its 2-pyridyl disulphide group via sulfhydryl exchange. The resulting complex was deposited on amino silanized mica where NHS-ester moiety of the cross linker reacted with the primary amino group on the surface. Samples were washed by a current of water and dried by an air jet in one direction parallel to the surface. DNA molecules were fully stretched in one direction on imaging them by AFM.