Treatment of carbon electrodes with Ti3C2Tx MXene coating and thermal method for vanadium redox flow batteries: a comparative study

One of the significant challenges of vanadium redox flow batteries is connected to the negative electrode where the main reaction of V(ii)/V(iii) and the side reaction of hydrogen evolution compete. To address this issue, we used titanium carbide (Ti3C2Tx) MXene coating via drop-casting to introduce oxygen functional groups and metals on the carbon electrode surface. Characterization through scanning electron microscopy and X-ray photoelectron spectroscopy confirmed the even distribution of Ti3C2Tx MXene on the electrodes and the presence of titanium and termination groups (-O, -Cl, and -F). The cyclic voltammetry analysis of MXene-coated electrodes showed more sharp electrochemical peaks for the V(ii)/V(iii) reaction than thermal-treated electrodes, even at relatively high scan rates. Notably, a relatively high reaction rate of 5.61 × 10-4 cm s-1 was achieved for the V(ii)/V(iii) reaction on MXene-coated electrodes, which shows the competitiveness of the method compared to thermal treatment (4.17 × 10-4 cm s-1). The flow battery tests, at a current density of 130 mA cm-2, using MXene-coated electrodes showed pretty stable discharge capacity for over 100 cycles. In addition, the voltage and energy efficiency were significantly higher than those of the system using untreated electrodes. Overall, this work highlights the potential application of MXene coating in carbon electrode treatment for vanadium redox flow batteries due to remarkable electrocatalytic activity and battery performance, providing a competitive method for thermal treatment.

The UHRF1 protein is a key regulator of retrotransposable elements and innate immune response to viral RNA in human cells

While epigenetic mechanisms such as DNA methylation and histone modification are known to be important for gene suppression, relatively little is still understood about the interplay between these systems. The UHRF1 protein can interact with both DNA methylation and repressive chromatin marks, but its primary function in humans has been unclear. To determine what that was, we first established stable UHRF1 knockdowns (KD) in normal, immortalized human fibroblasts using targeting shRNA, since CRISPR knockouts (KO) were lethal. Although these showed a loss of DNA methylation across the whole genome, transcriptional changes were dominated by the activation of genes involved in innate immune signalling, consistent with the presence of viral RNA from retrotransposable elements (REs). We confirmed using mechanistic approaches that 1) REs were demethylated and transcriptionally activated; 2) this was accompanied by activation of interferons and interferon-stimulated genes and 3) the pathway was conserved across other adult cell types. Restoring UHRF1 in either transient or stable KD systems could abrogate RE reactivation and the interferon response. Notably, UHRF1 itself could also re-impose RE suppression independent of DNA methylation, but not if the protein contained point mutations affecting histone 3 with trimethylated lysine 9 (H3K9me3) binding. Our results therefore show for the first time that UHRF1 can act as a key regulator of retrotransposon silencing independent of DNA methylation.

Excitonic effects on the optical spectra of TiB2nanosheets

Two-dimensional (2D) transition metal borides, have recently attracted tremendous interest and become an emerging class of 2D materials due to their intriguing properties. We report systematic investigation of stability, electronic properties and optical activity of 2D-TiB2nanosheets using first-principles calculations. By combining elastic and phonon-dispersion calculations, we substantiated the mechanical and dynamic stability of 2D-TiB2nanosheets. Our results of elastic calculations reveal that addition of an extra layer destroys the auxetic behaviour of monolayer (ML) 2D-TiB2with significant reduction in the brittleness. Further, based on the spin-polarised electronic structure calculations, we find that a low-dimensional metallic state of ML can be achieved by tuning the distance between the titanium and boron layers. The calculations clearly reveal that metallic nature does not destroys the auxetic behaviour of ML. Subsequently, we investigated the optical response of 2D-TiB2nanosheets (ML and bilayer (BL)) at the level of density functional theory and many-body perturbation theory. The results obtained by solving Bethe-Salpeter equation (GW+BSE formalism) shows that excitonic effects causes a slight blue-shift in the absorption spectra of the nanosheets with ML being optically active with sharp peaks in infrared (IR) and ultraviolet (UV) regions while BL shows the reduced optical activity across wide range of photon energies spanning the near-IR to UV region. In addition, electronic polarisability of the nanosheet decreases with addition of another layer in ML 2D-TiB2. Further investigation of transition probabilities clearly indicates that the response of ML at Dirac point is tunable by spin-orbital coupling effects which makes these nanosheets promising for spintronic applications. The BL exhibits distinct electronic, and optical properties compared to ML. Our study unravels the structural, elastic, electronic, and optical properties of 2D-TiB2nanosheets and suggests them as promising candidate for variety of optoelectronic and spintronic applications.

The Evolution of MXenes Conductivity and Optical Properties Upon Heating in Air

MXenes, a family of 2D transition-metal carbides and nitrides, have excellent electrical conductivity and unique optical properties. However, MXenes oxidize in ambient conditions, which is accelerated upon heating. Intercalation of water also causes hydrolysis accelerating oxidation. Developing new tools to readily characterize MXenes' thermal stability can enable deeper insights into their structure-property relationships. Here, in situ spectroscopic ellipsometry (SE) is employed to characterize the optical properties of three types of MXenes (Ti3 C2 Tx , Mo2 TiC2 Tx , and Ti2 CTx ) with varied composition and atomistic structures to investigate their thermal degradation upon heating under ambient environment. It is demonstrated that changes in MXene extinction and optical conductivity in the visible and near-IR regions correlate well with the amount of intercalated water and hydroxyl termination groups and the degree of oxidation, measured using thermogravimetric analysis. Among the three MXenes, Ti3 C2 Tx and Ti2 CTx , respectively, have the highest and lowest thermal stability, indicating the role of transition-metal type, synthesis route, and the number of atomic layers in MXene flakes. These findings demonstrate the utility of SE as a powerful in situ technique for rapid structure-property relationship studies paving the way for the further design, fabrication, and property optimization of novel MXene materials.

Initial Report of a Randomized Trial Comparing Conventional vs. Novel Treatment Planning Technique to Ameliorate Immunosuppression from Lung SBRT

PURPOSE/OBJECTIVE(S)

SBRT is highly effective against early-stage non-small cell lung cancer. Radiation Therapy (RT) is known to modulate the immune system and contribute to the generation of anti-tumor T cells and stimulate T cell infiltration into tumors. However, this anti-tumor activity is offset by radiation-induced immunosuppression (RIIS) which results in lower tumor control and survival. Lymphocytes are highly radiosensitive and RIIS means destroying existing as well as newly created cytotoxic and helper T lymphocytes. We hypothesized that optimizing RT treatment planning by considering circulating blood and lymphatics as a critical Organ at Risk (OAR) may mitigate RIIS.

MATERIALS/METHODS

We conducted an IRB approved NCI funded clinical trial for 50 early-stage lung cancer patients treated with SBRT alone, from 2020 to 2023, to investigate the ability to reduce RIIS by reducing dose to circulating blood and lymphatics with the aid of a predictive algorithm. All SBRT plans adhered to treatment parameters from RTOG 0813 (central) or RTOG 0915 (peripheral). Patients were randomized to two arms: experimental optimization for RIIS (to reduce dose to blood and lymphatic rich organs) versus standard SBRT planning (without optimization for RIIS). Peripheral blood samples were collected at baseline, end of Tx, 4 weeks and 6 months post Tx. Patients with baseline absolute lymphocyte counts (ALC) less than 0.5x109 cells/L were ineligible for the trial. Data acquired for all blood cell types as well as lymphocyte sub populations CD3+, CD4+, CD8+, CD19+, CD56+. Two sample t-test was used to determine the statistical significance between the cohorts at the time points.

RESULTS

The standard arm had an ALC reduction of 28% at one week post Tx and a nadir at 4 weeks with a 34% reduction. Absolute percentage reductions in ALC from baseline in the optimized arm compared to the standard arm are: end of treatment point (13%, p = 0.03), 4 weeks (12%, p = 0.08), 6 months (15%, p = 0.1), and all three time points together 13% (p = 0.001). ALC recovery appears to be faster in the optimized arm. Radiation induced suppression of all blood cell types are also reduced in the optimized arm with respect to standard arm (relative percentages): ALC (34%), WBC (47%), RBC (46%), platelets (40%), monocytes (100%), and neutrophils (62%) at 4-week mark. Average percentage reductions on integral doses, and V5 (volume receiving a 5 Gy dose) of optimized compared to standard plans are: aorta: 26%, 41% heart: 8%, 33%, vena cava: 32%, 52%, T spine: 51%, 81%, lymph nodes: 35%, 57%, total lung- ITV: 1.6%, 1%, body: 10%, 14%.

CONCLUSION

For the first time, we have shown that it is possible to reduce RIIS in a statistically significant manner, compared to standard of care, via optimized RT planning using a predictive model. This has implications in increasing the efficacy of immunotherapy by preserving the existing tumor reactive T cells in the immune system to enhance anti-tumor activity, and in reducing hospitalizations and improving survival.

The relationship between physical activity, structural deformity, and spinal mobility in adolescent idiopathic scoliosis patients

PURPOSE

Adolescent idiopathic scoliosis (AIS) patients experience structural spinal deformity, but the impact of AIS on physical activity is not widely studied. Reports of physical activity levels between children with AIS and their peers are mixed. This study sought to characterize the relationship between spinal deformity, spinal range of motion, and self-reported physical activity in AIS patients.

METHODS

Patients aged 11-21 completed self-reported measures of physical activity using the HSS Pedi-FABS and PROMIS Physical Activity questionnaires. Radiographic measures were obtained from standing biplanar radiographic imaging. Surface topographic (ST) imaging data was obtained using a whole-body ST scanning system. Hierarchical linear regression models analyzed the relationship between physical activity, ST, and radiographic deformity while controlling for age and BMI.

RESULTS

149 patients with AIS (mean age 14.5 ± 2.0 years, mean Cobb angle 39.7° ± 18.9°) were included. In the hierarchical regression predicting physical activity from Cobb angle, no factors were significant predictors of physical activity. When predicting physical activity from ST ROM measurements, age and BMI served as covariates. No covariates or ST ROM measurements were significant predictors of physical activity levels for either activity measure.

CONCLUSIONS

Physical activity levels of patients with AIS were not predicted by levels of radiographic deformity or surface topographic range of motion. Although patients may experience severe structural deformity and range of motion limitations, these factors do not appear to be associated with decreased physical activity level utilizing validated patient activity questionnaires.

LEVEL OF EVIDENCE

Level II.

Double-Transition-Metal MXene Films Promoting Deeply Rechargeable Magnesium Metal Batteries

Magnesium metal batteries are promising candidates for next-generation high-energy-density and low-cost energy storage systems. Their application, however, is precluded by infinite relative volume changes and inevitable side reactions of Mg metal anodes. These issues become more pronounced at large areal capacities that are required for practical batteries. Herein, for the first time, double-transition-metal MXene films are developed to promote deeply rechargeable magnesium metal batteries using Mo2 Ti2 C3 as a representative example. The freestanding Mo2 Ti2 C3 films, which are prepared using a simple vacuum filtration method, possess good electronic conductivity, unique surface chemistry, and high mechanical modulus. These superior electro-chemo-mechanical merits of Mo2 Ti2 C3 films help to accelerate electrons/ions transfer, suppress electrolyte decomposition and dead Mg formation, as well as maintain electrode structural integrity during long-term and large-capacity operation. As a result, the as-developed Mo2 Ti2 C3 films exhibit reversible Mg plating/stripping with high Coulombic efficiency of 99.3% at a record-high capacity of 15 mAh cm-2 . This work not only sheds innovative insights into current collector design for deeply cyclable Mg metal anodes, but also paves the way for the application of double-transition-metal MXene materials in other alkali and alkaline earth metal batteries.

Step-by-Step Guide for Synthesis and Delamination of Ti3 C2 Tx MXene

To advance the MXene field, it is crucial to optimize each step of the synthesis process and create a detailed, systematic guide for synthesizing high-quality MXene that can be consistently reproduced. In this study, a detailed guide is provided for an optimized synthesis of titanium carbide (Ti3 C2 Tx ) MXene using a mixture of hydrofluoric and hydrochloric acids for the selective etching of the stoichimetric-Ti3 AlC2 MAX phase and delamination of the etched multilayered Ti3 C2 Tx MXene using lithium chloride at 65 °C for 1 h with argon bubbling. The effect of different synthesis variables is investigated, including the stoichiometry of the mixed powders to synthesize Ti3 AlC2 , pre-etch impurity removal conditions, selective etching, storage, and drying of MXene multilayer powder, and the subsequent delamination conditions. The synthesis yield and the MXene film electrical conductivity are used as the two parameters to evaluate the MXene quality. Also the MXenes are characterized with scanning electron microscopy, x-ray diffraction, atomic force microscopy, and ellipsometry. The Ti3 C2 Tx film made via the optimized method shows electrical conductivity as high as ≈21,000 S/cm with a synthesis yield of up to 38 %. A detailed protocol is also provided for the Ti3 C2 Tx MXene synthesis as the supporting information for this study.

Nitrogen adsorption via charge transfer on vacancies created during surfactant assisted exfoliation of TiB2

Titanium diboride (TiB₂), a layered ceramic material, comprised of titanium atoms sandwiched in between honeycomb planes of boron atoms, exhibits a promising structure to utilize the rich chemistry offered by the synergy of titanium and boron. TiB₂ has been primarily investigated and applied in its bulk form. This perspective is, however, fast evolving with a number of efforts aimed at exfoliating TiB₂. Here, we show that it is possible to delaminate TiB₂ into ultrathin, minimally functionalized nanosheets with the aid of surfactants. These nanosheets exhibit crystalline nature and their chemical analysis reveals vacant sites within the nanosheets. These vacancies facilitate the chemisorption of N₂ onto the TiB₂ nanosheets under ambient conditions without the aid of any energy, this finding was unexpected. This remarkable activity of TiB₂ nanosheets is attributed to vacancies and the Ti-B synergy, which enhance the adsorption and activation of N₂. We obtained supplemental insights into the N₂ adsorption by Density Functional Theory (DFT) studies, which reveal how charge transfer among Ti, B, and N₂ results in N₂ adsorption. The DFT studies also show that nanosheets having more vacancies result in increased adsorption when compared with nanosheets having less vacancies and bulk TiB₂.

Design of Atomic Ordering in Mo2Nb2C3Tx MXenes for Hydrogen Evolution Electrocatalysis

The need for novel materials for energy storage and generation calls for chemical control at the atomic scale in nanomaterials. Ordered double-transition-metal MXenes expanded the chemical diversity of the family of atomically layered 2D materials since their discovery in 2015. However, atomistic tunability of ordered MXenes to achieve ideal composition-property relationships has not been yet possible. In this study, we demonstrate the synthesis of Mo_2+αNb_2-αAlC₃ MAX phases (0 ≤ α ≤ 0.3) and confirm the preferential ordering behavior of Mo and Nb in the outer and inner M layers, respectively, using density functional theory, Rietveld refinement, and electron microscopy methods. We also synthesize their 2D derivative Mo_2+αNb_2-αC₃T_x MXenes and exemplify the effect of preferential ordering on their hydrogen evolution reaction electrocatalytic behavior. This study seeks to inspire further exploration of the ordered double-transition-metal MXene family and contribute composition-behavior tools toward application-driven design of 2D materials.

Plasmonic Copper-activated ZnO Microarrays for Efficient Photoelectrocatalytic Applications

In the present work, green synthesized plasmonic copper nanostructures derived from carbon quantum dots (PCQDs) activated ZnO microarrays (MAs) based catalyst system is developed and studied for photocatalytic activity and photoelectrocatalytic water splitting. CQDs are synthesized from pharmaceutical waste and used as a reducing agent to synthesize PCQDs of an average size of 10±2 nm. PCQDs decorated ZnO (PCQDs/ZnO) MAs exhibited enhanced photocurrent density of ∼7.1 mA/cm² at 1.23 V (vs. RHE), which is ∼11 fold to ZnO MAs alone (0.65 mA/cm² ). The catalyst exhibits an ABPE of 1.07% at 0.7 V (vs. RHE), IPEC of 8.8% for 450 nm, and hydrogen production rate of 435 μmol/h. The enhanced PEC characteristics are assigned to the improved photons collection and better charge transfer for their participation in oxidation/reduction reaction. The same is well supported with DFT studies for the PCQDs/ZnO MAs catalyst for the first time.

Spherical Templating of CoSe2 Nanoparticle-Decorated MXenes for Lithium-Sulfur Batteries

Two-dimensional MXenes produce competitive performances when incorporated into lithium-sulfur batteries (LSBs), solving key problems such as the poor electronic conductivity of sulfur and dissolution of its polysulfide intermediates. However, MXene nanosheets are known to easily aggregate and restack during electrode fabrication, filtration, or water removal, limiting their practical applicability. Furthermore, in complex electrocatalytic reactions like the multistep sulfur reduction process in LSBs, MXene alone is insufficient to ensure an optimal reaction pathway. In this work, we demonstrate for the first time a loose templating of sulfur spheres using Ti₃C₂T_x MXene nanosheets decorated with polymorphic CoSe₂ nanoparticles. This work shows that the templating of sulfur spheres using nanoparticle-decorated MXene nanosheets can prevent nanosheet aggregation and exert a strong electrocatalytic effect, thereby enabling improved reaction kinetics and battery performance. The S@MXene-CoSe₂ cathode demonstrated a long cycle life of 1000 cycles and a low capacity decay rate of 0.06% per cycle in LSBs.

Mental health and COVID-19: The impact of a virtual course for family caregivers of adults with intellectual and developmental disabilities

BACKGROUND

The COVID-19 pandemic has significantly impacted family caregivers of adults with intellectual and developmental disabilities (IDD). This study evaluated a virtual course for family caregivers from across Canada, focused on supporting the mental health and well-being of adults with IDD and their families. The evaluation examined the feasibility and acceptability of the course, as well as the impact of the intervention on participants' overall health and well-being.

METHODS

The 6-week virtual course, informed by a parallel Extension for Community Healthcare Outcomes (ECHO) course for service providers, combined didactic instruction with applied activities. A total of 126 family caregiver course participants consented to be part of the research evaluation delivered over three cycles between October 2020 and April 2021. Attendance was measured at each weekly session. Satisfaction was assessed weekly and post-program. Learning, self-efficacy, and well-being were assessed pre- and post-course, and again at follow-up (8 weeks post-course). Mixed-effects models assessed changes between and within individuals across time.

RESULTS

Participants had consistent attendance, low-dropout rates, and reported high satisfaction, with 93% of participants reporting that their expectations for the course were met. Compared with pre-course, participants reported improved self-efficacy and well-being post-course, which were maintained at follow-up.

CONCLUSIONS

An interactive and applied virtual education course delivered to a large group of family caregivers of adults with IDD was both feasible and acceptable. It positively impacted participants' well-being by offering much needed mental health support and creating a peer-led community of practice.

A Comprehensive Review on Water Quality Monitoring Devices: Materials Advances, Current Status, and Future Perspective

Water quality monitoring has become more critical in recent years to ensure the availability of clean and safe water from natural aquifers and to understand the evolution of water contaminants across time and space. The conventional water monitoring techniques comprise of sample collection, preservation, preparation, tailed by laboratory testing and analysis with cumbersome wet chemical routes and expensive instrumentation. Despite the high accuracy of these methods, the high testing costs, laborious procedures, and maintenance associated with them don't make them lucrative for end end-users and field testing. As the participation of ultimate stakeholders, that is, common man for water quality and quantity can play a pivotal role in ensuring the sustainability of our aquifers, thus it is essential to develop and deploy portable and user-friendly technical systems for monitoring water sources in real-time or on-site. The present review emphasizes here on possible approaches including optical (absorbance, fluorescence, colorimetric, X-ray fluorescence, chemiluminescence), electrochemical (ASV, CSV, CV, EIS, and chronoamperometry), electrical, biological, and surface-sensing (SPR and SERS), as candidates for developing such platforms. The existing developments, their success, and bottlenecks are discussed in terms of various attributes of water to escalate the essentiality of water quality devices development meeting ASSURED criterion for societal usage. These platforms are also analyzed in terms of their market potential, advancements required from material science aspects, and possible integration with IoT solutions in alignment with Industry 4.0 for environmental application.

A Study on the Effect of Soil and Sediment Types on the Fugacity Based Multimedia Partitioning of a Contact Fungicide Fluopyram: An Equilibrium Quality Criterion (EQC) Level 1 Approach

Equilibrium Quality Criterion (EQC) Level I calculations have been performed with Standard Equilibrium Quality Criterion (EQC) environment to study the environmental partitioning of a fungicide Fluopyram. Equilibrium Quality Criterion (EQC) Level I calculation assumes no degradation of the chemical, steady-state, and equilibrium conditions between the environmental compartments. The results reveal that the concentration of Fluopyram is expected to be maximum in the sediment compartment, followed by soil and water compartments. The effect of soil and sediment types on partitioning has been studied by systematically varying the densities of these two compartments. In the sediment compartment, the Fluopyram concentration is predicted to be highest if the sediment type is ‘sandy’ and the soil type is ‘clay’.

LV-GLS is a predictor of all-cause death and cardiovascular MACE events in patients with neuro-immunological disorders

Background

Neuro-immunological disorders encompass several disease states, including multiple sclerosis (MS), autoimmune encephalitis (AE) and myasthenia gravis (MG). These autoimmune conditions are mediated via pro-inflammatory cytokines, and there is growing evidence to suggest cardiovascular involvement within these inflammatory states. Left ventricular global longitudinal strain (LV-GLS) is proposed to be a more sensitive measure of LV systolic function when compared to standard two-dimensional measures such as LV ejection fraction (LVEF).

Purpose

The purpose of this study was to assess for subclinical cardiac dysfunction in a cohort of patients with neuro-immunological disorders and correlate this with the development of outcomes on follow-up.

Methods

Consecutive patients with MS, AE and MG admitted to our institution during 2013–2020 were assessed (n=102). Patients without pre-existing cardiovascular disease, LVEF <50% or lack of comprehensive transthoracic echocardiography during their index admission were included (n=55). This group was compared to age- and gender-matched controls (n=55) LV-GLS was measured offline using vendor-independent software (TomTec Arena, Germany v4.6) by two cardiologists blinded to the patient group or outcomes. These patients were followed for up for the composite outcome of all-cause death and major adverse cardiovascular events (MACE).

Results

A total of 55 patients (31 MS, 14 AE and 10 MG) were age- and gender- matched to 55 controls. There was no significant difference in baseline demographic characteristics or cardiovascular risk factors between groups. Patients with neuro-immunological disorders demonstrated impaired LV-GLS (−17.6±3.5 vs −20.8±1.9; p<0.01) when compared to healthy controls, despite an LVEF within the normal range (60.9±7.7 vs 64.1±5.7; p=0.02) in both groups. There were a total of 9 (16.4%) outcomes during a mean follow-up of 41.0±33.0 months. LV-GLS was the only significant echocardiographic predictor of all-cause death and MACE events (p=0.013) on multi-variate analysis.

Conclusions

Our results suggest that patients with neuro-immunological disorders have subclinical LV dysfunction as assessed by LV-GLS which has prognostic capacity in this population. Further larger studies are required to further characterize this phenomenon.

Funding Acknowledgement

Type of funding sources: None.

Patients with rare autoimmune inflammatory disorders demonstrate sub-clinical left ventricular dysfunction

Background

ANCA-associated Vasculitis (AAV) and inflammatory myositis (IM) are rare inflammatory autoimmune disorders mediated via pro-inflammatory cytokines and result in a systemic inflammatory state with multi-organ involvement. There is growing evidence to suggest cardiovascular involvement within these inflammatory states. Left ventricular global longitudinal strain (LV-GLS) is proposed to be a more sensitive measure of LV systolic function when compared to standard two-dimensional measures such as LV ejection fraction (LVEF).

Purpose

The purpose of this study was to assess for subclinical cardiac dysfunction in these cohorts when compared to controls.

Methods

Consecutive patients with AAV (n=56) and IM (n=68) admitted to our institution during 2013–2021 were assessed. Patients with pre-existing cardiovascular disease, significant renal impairment (eGFR <30mL/min/1.73m2), LVEF <50% or lack of comprehensive transthoracic echocardiography during admission were excluded (n=72). LV-GLS was measured offline using vendor-independent software (TomTec Arena, Germany v4.6).

Results

A total of 52 patients (22 AAV and 30 IM) were age- and gender-matched to 52 controls. In comparison of the two study populations (AAV and IM), patients with AAV had higher rates of renal impairment (p=0.02) but lower rates of interstitial lung disease when compared to IM (p=0.02). There were no differences between the two groups in terms of cardiovascular risk factors, demographics or other laboratory investigations (p>0.05 for all). In comparison to the control population, patients with AAV and IM had higher indexed LV mass and a lower TAPSE, respectively, when compared to controls. These cohorts also demonstrated impaired LV-GLS (−17.7±2.6 vs −20.6±2.4; p<0.01) when compared to healthy controls, despite no differences in LVEF (62.6±7.8 vs 61.8±5.4; p=0.56) between both groups.

Conclusions

Our results suggest that patients with autoimmune inflammatory disorders demonstrate subclinical LV dysfunction which is likely secondary to a chronic inflammatory state.

Funding Acknowledgement

Type of funding sources: None.

Nanostructures derived from expired drugs and their applications toward sensing, security ink, and bactericidal material

In this research, a facile and economical route is introduced for the transformation of pharmaceutical waste (i.e., expired medicines) into value-added fluorescent carbon quantum dots (pharmaceutically derived CQDs abbreviated as 'P-CQDs'). The synthesized P-CQDs were identified to have surface functionalities of -OH, C=O, and C=C with an average size of ~2-3 nm and a high quantum yield of 35.3%. The photoluminescence of P-CQDs recorded a maximum optical emission intensity at 2.8 eV (425 nm). The binding of Cu (II) ions by -COOH functionalities on the surface of P-CQDs led to its fluorescence quenching (turn-off) over a wide Cu (II) concentration range of 0.25-50 ppm. The P-CQDs exhibited the detection limit of 0.66 ppm (well below the WHO permissible limit of 2 ppm). The fluorescence intensity of the P-CQDs-Cu (II) complex was recovered from NaHCO_3.Hence, their "off-on" behavior was also explored for security ink applications for information encryption and decryption. Moreover, the rich oxygenated groups on the surface of the P-CQDs were utilized for green synthesis of plasmonic Ag@P-CQDs nanostructures, which were also demonstrated to have enhanced potential as bactericidal materials (e.g., against both E. coli and S. aureus). The overall results of this study are demonstrated to help create new and diverse routes for converting expired drugs into value-added nanostructures.

143 Therapeutic efficacy and safety of adipose tissue-derived mesenchymal stem cells in treating mastitis and metritis in dairy cattle

Mastitis and metritis are two inflammatory diseases with high economic impact on dairy industry and farmers are losing revenues. Antibiotic treatment for these disease conditions typically achieve suboptimal outcomes. Moreover, emerging antibiotic resistance in mastitis and metritis worldwide has a severe effect on productivity, fertility, and lifespan of animals. A paradigm shift in treatment strategies is much needed for these animals. Attracting properties of mesenchymal stem cells may act as an alternative strategy for treating these diseases. In addition to their ability to differentiate into multiple types of cells, mesenchymal stem cells can orchestrate immune responses and modulate tissue microenvironments. In the present study, we evaluated the safety and efficacy of adipose tissue–derived mesenchymal stem cells (AT-MSC) for mastitis and metritis. A well-characterised adipose-derived stem cell line with 3–5 passages cells were used for treatment for these diseases. In a safety trial, mastitis- and metritis-infected cattle were administered with 1×106 cells of AT-MSC through different routes (local, IV, IV+local). Animals were clinically evaluated during 15 days of the experimental period and blood samples were collected for hemogram determination. The efficacy was checked under both invivo and invitro conditions. Invitro efficiency of AT-MSC was determined using a transwell plate experiment, in which AT-MSC were co-cultured with bacteria (Escherichia coli and Staphylococcus). Invivo efficiency was evaluated by administration of in 2mL (1×106 cells) of AT-MSC dose; then, somatic cell count (SCC) in milk of mastitic cattle and polymorphonuclear (PMN) cell count in cervical vaginal fluid (CVF) of metritic cattle were determined. Gene expression profiling of antimicrobial (cathelicidin, lipocalin, cystatin) and anti-inflammatory (IL-4, IL-6, IL-10) peptides were quantified in all groups: IV, local, IV+local, and control ATB (antibiotic). Allogenic AT-MSC did not induce any immunological rejection response in treated animals. A significant reduction of bacteria in CVF invitro when co-cultured with AT-MSC was observed. The PMN count was significantly reduced in CVF of the IV+local group. The SCC in milk of mastitic animals was decreased in the local (intramammary) group. Maximum expression of IL-6, IL-10, cathelicidin, lipocalin, and cystatin and angiopoietin genes were observed on Day 3 followed by Day 7 in the local group in case of mastitis. In metritis, expression of IL-6, IL-10, cathelicidin, lipocalin, cystatin, and angiopoietin were observed at Day 3 in the IV+local group. All mastitic and metritic cattle were completely and permanently cured within 30 days after treatment with mesenchymal stem cells. In conclusion, we provide initial evidence for the use of allogenic AT-MSC and their safety and efficacy to treat mastitis and metritis in dairy cattle.

Improvement of Ejection Fraction in Patients undergoing Coronary Artery Bypass Grafting with Impaired Left Ventricular Function

Background Myocardial revascularization surgery has shown better long term survival expectancy compared to medical therapy in patient with impaired left ventricular function. Objective To evaluate the change in ejection fraction after 90 days in patients who underwent coronary artery bypass surgery and had preoperative left ventricular ejection fraction of less than and equal to 45% in a single cardiac center of Nepal over the period of 2 years. Method Out of 82 eligible patients during 2 years, 3 patients expired in immediate postoperatively and 24 patients had loss of 90 days' follow up. So, they were excluded from the study. Total 55 patients were taken for the study for whom statistical analysis was done to compare preoperative ejection fraction with post-operative 90 days' ejection fraction. Result Single vessel disease was present in 2(3.6%) patients, double vessel disease in 7(12.7%) patients and triple vessel disease in 46(83.6%) of the patients. In 2(3.6%) patients 2 grafts, in 18(32.7%) patients 3 grafts, in 33(60%) patients 4 grafts and in 2(3.6%) patients 5 grafts were placed for revascularization. The mean left ventricular EF in preoperative patients was 37.12±5.69% which improved to 45.80±10.00% in postoperative follow up at 90 days which was statistically significant (p=0.000). Conclusion Surgical revascularization of myocardium in preoperatively impaired left ventricular function patients helps improve left ventricular ejection fraction postoperatively. So we suggest surgical revascularization in patient with low ejection fraction for improvement of myocardial function. Hence improve survival rate in these patients.

Label-free sensing of exosomal MCT1 and CD147 for tracking metabolic reprogramming and malignant progression in glioma

Malignant glioma is a fatal brain tumor whose pathological progression is closely associated with glycolytic reprogramming, leading to the high expression of monocarboxylate transporter 1 (MCT1) and its ancillary protein, cluster of differentiation 147 (CD147) for enhancing lactate efflux. In particular, malignant glioma cells (GMs) release tremendous number of exosomes, nanovesicles of 30 to 200 nm in size, promoting tumor progression by the transport of pro-oncogenic molecules to neighboring cells. In the present study, we found that hypoxia-induced malignant GMs strongly enhanced MCT1 and CD147 expression, playing a crucial role in promoting calcium-dependent exosome release. Furthermore, it was first identified that hypoxic GMs-derived exosomes contained significantly high levels of MCT1 and CD147, which could be quantitatively detected by noninvasive localized surface plasmon resonance and atomic force microscopy biosensors, demonstrating that they could be precise surrogate biomarkers for tracking parent GMs' metabolic reprogramming and malignant progression as liquid biopsies.

Impact of antagonistic crustaceans on the population of Aedes aegypti L. larvae under laboratory conditions

BACKGROUND & OBJECTIVES

Dengue and chikungunya are two mosquito-borne viral diseases transmitted by Aedes mosquito species and are a great public health concern in India. The present study was aimed to check the influence of antagonistic crustaceans, especially Mesocyclops aspericornis and Daphnia magna on Ae. aegypti L. mosquito population.

METHOD

Variable ratios of these crustaceans (Aedes: Mesocyclops: Daphnia) against Ae. aegypti larvae were tested by putting them in plastic beakers having dechlorinated water along with yeast stock solution provided as food, and kept in BOD incubator at a temperature of 26 ±1°C.

RESULTS

Out of all tested concentrations, 1:1:3 where the number of D. magna was thrice the number of Mesocyclops and Aedes; larvae showed a significant delay of 5-6 days in the developmental period. Maximum reduction in the emergence of females was recorded in the ratio 1:1:3, i.e. only 6.5 ± 0.47 females emerged when Daphnia used thrice the number of Aedes larvae. Body size of both males and females emerged from treated sets was found to be significantly reduced. The longevity of adults was also reduced from 8-17 days to 5-8 days in the case of males and from 14-26 days to 5-9 days in females.

INTERPRETATION & CONCLUSION

Among variable ratios tested under laboratory conditions, 1:1:2 and 1:1:3 ratios were found to be the effective ratios that greatly reduced the development duration, survivorship of larvae, and the number of larvae emerging into adulthood. Thus, antagonistic crustaceans specifically Mesocyclops and Daphnia can be used as biocontrol agents for the sustainable control of container breeding mosquitoes.

TiO2 nanofibres decorated with green-synthesized PAu/Ag@CQDs for the efficient photocatalytic degradation of organic dyes and pharmaceutical drugs

Citrus limetta waste-derived plasmonic nanostructures for photocatalytic degradation of toxic dyes and pharmaceutical pollutants in water.

P1530 Dense spontaneous echo contrast and thrombus in patients on new oral anticoagulant and warfarin therapy: a retrospective audit

Background

Cardioembolic stroke is a known complication of atrial fibrillation (AF), which is increasing in global prevalence. Spontaneous echo contrast (SEC) in the left atrium (LA) is a precursor for thrombus formation detected on transesophageal echocardiography (TEE). There is limited data regarding the prevalence of dense SEC and/or left atrial thrombus (LAT) detected by TEE in patients on novel oral anticoagulants (NOACs) compared with Warfarin.

Purpose

To determine and compare the prevalence of dense SEC and/or LAT among patients with AF/atrial flutter undergoing TEE while on continuous NOAC or Warfarin therapy.

Methods

Retrospective analysis of prospectively entered data for all patients who were on continuous oral anticoagulants and underwent TEE with DC cardioversion, over a 9-year period (1st January 2011 to 31st December 2018) at a public teaching hospital in NSW, Australia. SEC was classified according to emptying flow velocities, as per the European Association of Cardiovascular Imaging guidelines.

Results

Among the 195 patients, 94 (48%) patients were on NOAC therapy (52% Apixaban, 25% Rivaroxaban, 23% Dabigatran) while 101 (52%) patients were on Warfarin. There was no difference in age (mean ± SD: 64 ± 12 vs. 65 ± 13, p = 0.71) or proportion of males (71% vs 69%, p = 0.76) between patients on NOAC therapy compared with Warfarin. However, the NOAC therapy group had a lower prevalence of ischaemic heart disease (IHD) (18% vs. 33%, p < 0.05) and chronic kidney disease (CKD) (2% vs. 19%, p < 0.001), in addition to a lower CHA2DS2-VASc score (2.1 ± 1.7 vs 2.7 ± 1.7, p = 0.03) and higher haemoglobin levels (145.3 ± 19 vs 133.8 ± 24, p = 0.001). The overall rate of dense SEC and/or LAT detected by TEE was 9.7%. There was no significant difference in the prevalence of dense SEC and/or LAT between patients on NOACs and Warfarin (6.4% vs. 12.9%, p = 0.13). On multivariable analysis of IHD, CKD, Warfarin, NOACs and CHA2DS2-VASc score, there was no significant difference in prevalence of SEC/LAT between Warfarin and NOACs.

Conclusions

In this study, 6.4% of patients on continuous NOACs and 12.9% of patients on Warfarin therapy had dense SEC and/or LAT detected by TEE. Although the trend towards higher rates of dense SEC and pre-thrombus in the Warfarin group did not reach statistical significance, it still holds clinical significance as these patients cannot be cardioverted. Therefore, these data support the need to consider anticoagulant optimisation in the overall management of patients with SEC.

Abstract P1-08-05: A phase I trial of chemotherapy followed by infusions of activated T cells armed with anti-CD3 and anti-HER2 bispecific antibody for stage III, Her2+ or Her2- breast cancer

Background: The balance in the immune system between immune surveillance and tolerance is known to be associated with the prognosis of breast cancer patients. The aim of this phase I study was to assess the safety of anti-CD3 x anti-HER2Bi bispecific antibody targeted (BAT) activated T cells (TC) in high risk breast cancer patients. The BAT T-cells exhibit anti-HER2 cytotoxicity, proliferate, and secrete immunokines upon tumor engagement.

Methods: High risk adjuvant breast cancer patients were recruited and completed standard adjuvant chemotherapy. BATs were produced by stimulating peripheral blood mononuclear cells (PBMC) obtained by leukapheresis; collected TC were then activated with anti-CD3 monoclonal antibody and expanded in IL-2 for 12-14 days. TC were armed with bispecific antibody and cryopreserved until used. Groups of 3 patients received 20, 40, 80 or 160 x 109 BATs per infusion twice a week for four weeks. All patients were treated at Roger Williams Medical Center.

Results: Nine patients were accrued and all had N3 disease. Eight of 9 patients were ER positive; 2 of 9 were HER2 overexpressing. The median OS has not reached as five of nine patients are still alive. OS range from 14.3 to 154.7 months (as December 11, 2016). Five out of the five patients who are alive have no evidence of disease and 1 patient had a secondary primary that has been successfully treated and she has no evidence of disease. It was feasible to grow up to 160 x 109 BATs and this dose level was tolerable without any cell-based dose limiting toxicities. BATs persisted in the blood for at least a week. BAT infusions induce cellular anti-tumor responses and cytokine responses.

Conclusion: Targeting HER2 positive and negative tumors induced cytotoxic anti-tumor responses, increases in Th1 cytokines and IL-12 serum levels. The prolonged survival in a high risk population suggests that BAT infusions provided a clinical benefit. These results are being confirmed in a phase II trial for metastatic breast cancer.

Citation Format: Dillon P, Rathore R, Thakur A, Colvin G, Kouttab N, Lum L. A phase I trial of chemotherapy followed by infusions of activated T cells armed with anti-CD3 and anti-HER2 bispecific antibody for stage III, Her2+ or Her2- breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P1-08-05.

179 Xenogeneic and Allogeneic Mesenchymal Stem Cell Transplantation for Treatment of Tibial Bone Fracture in Mice

Among stem cells, mesenchymal stem cells (MSC) are best suited for therapeutic purposes because of their immunomodulatory properties, ability to be isolated from adult animal at any stage, ease of propagation in the laboratory, and so on. The present study was carried out to isolate and characterise MSC from adipose tissue of mouse (Mus musculus), and to test their application for the treatment of fractured tibia bone in mouse. Cattle and buffalo MSC, already cultured and characterised in our laboratory, were used in the present study as xenogeneic MSC to observe the healing in mouse model. Murine Ad-MSC were isolated from mouse inguinal fat pad by enzymatic digestion method and cultured in growth enriching medium in standard culture conditions. To test the therapeutic potential of MSC, 24 mice were divided into 4 groups: control (C), allogeneic (A), cattle xenogeneic (CX), and buffalo xenogeneic (BX) with 6 mice (having tibial bone mechanical fractured) in each group, and had the corresponding MSC cells injected in the fracture area. The control group was not subjected to any kind of MSC treatment. Post-treatment, healing in all groups was examined for 36 days at different intervals (Days 1, 12, 24, and 36) via digital X-ray imaging. A bone healing score was assigned to each mouse per the protocol provided by RUST (Radiographic Union Scale in Tibial bone) fractures. The results of present study showed that murine Ad-MSC were positive for MSC-specific markers CD44, CD90, CD105, and negative for CD34 and CD45 via RT-PCR and immunocytochemistry. The Ad-MSC were also positive for the alkaline phosphatase staining. Statistical analysis, using Proc GLM (SAS Institute Inc., Cary, NC, USA), revealed that the bone healing was significantly different (P < 0.01) between group C (1.708 ± 0.059) and other groups [group A (2.125 ± 0.061), CX (2.167 ± 0.068), BX (2.250 ± 0.068)], suggesting that healing was greater in groups transplanted with MSC compared with control. However, healing between groups transplanted with MSC (A, CX, and BX) was not significantly different (P > 0.05). In conclusion, we have observed the healing potential of MSC in mouse model via allogeneic and xenogeneic MSC transplantation; the healing potential among the A, CX, and BX MSC groups was similar.

170 Effect of Folic Acid Supplementation on In Vitro Maturation of Oocytes and Folate Cycle

Folic acid (vitamin B9) is the principal component of one-carbon (C1) metabolism in mammalian cells. It acts as a coenzyme in C1 unit transfer during nucleotide and amino acid metabolism. Therefore, it is unquestionably essential for the formation of thymidylate (TMP) for DNA synthesis and methylation, which is in turn crucial for post-implantation embryonic brain and nerve chord development. However, the role of folic acid in maturation of oocytes and subsequent blastocyst production is largely ambiguous in different mammalian species. The aim of this study was to investigate the effect of folic acid supplementation on expression of oocyte maturation markers and folate cycle enzymes in cumulus cells in addition to blastocyst development rate in goat. Immature oocytes were isolated from ovaries, and 1600 oocytes were matured in maturation medium (medium-199) supplemented with 0 (control), 50, 100, or 150 µM folic acid (Sigma Aldrich, India), comprising total 400 oocytes in each group in 5 replicates. The oocytes were in vitro fertilized and embryos were cultured for 7 days. Blastocyst rate was calculated in all 4 groups. Cumulus cells from matured oocytes from each group were analysed for the differential expression of oocyte maturation markers: PTX3, PTGS2, CTSB, and CTSS, and folate cycle enzyme transcripts MTR, MAT2A, ACHY, DHFR, and SLC19A1, by qRT-PCR. For statistical analysis, one-way ANOVA was used. The results of present study show that blastocyst rate was significantly higher (P ≤ 0.05) at 50 µM folic acid (21.4 ± 1.2%) compared with control (13.6 ± 0.4%), 100 µM (10.4 ± 0.34%), and 150 µM (7.4 ± 0.54%). However, there was no effect on the number of cleaved embryos among control (72 ± 0.21%), 50 µM (70.6 ± 0.58%), 100 µM (73.75 ± 0.31%), and 150 µM (73.02 ± 0.04%). The expression of the oocyte maturation markers PTX3 and PTGS2 was up-regulated, whereas that of CTSS and CTSSB was down-regulated (P ≤ 0.05), in the 50 µM group, but did not change (P ≤ 0.05) among the other groups. The expression of these genes did not change significantly among the other groups. The expression of genes of the folate cycle, MTR, MAT2A, ACHY, and DHFR, increased (P ≤ 0.05) by 5.7-, 3.6-, 2.2-, and 1.7-fold, respectively, at 50 µM, but did not change (P ≤ 0.05) among the other groups. The expression of SLC19A1 did not change significantly among all the groups. The results of present study show that the supplementation of 50 µM folic acid to the maturation medium results in increased maturation of oocytes, making them more competent for the blastocyst development. Up-regulation of transcripts of folate cycle enzymes at 50 µM might explain the increase in the blastocyst production rate, which further needs to be validated.