A255 INCREASED ENERGY EXPENDITURE AND REDUCED EXERCISE CAPACITY IN CELIAC DISEASE PATIENTS ON A GLUTEN-FREE DIET

Background

Celiac disease (CeD) patients often exhibit impaired nutritional status due to nutrient malabsorption and altered metabolism. Accurate clinical assessment of malnutrition, muscle function and energy requirements are thus essential to prevent and treat malnutrition. Indirect calorimetry (IC) is the most accurate method to measure energy needs, but it is underutilized in outpatient settings.

Aims

To assess the use of IC testing in estimating the resting energy expenditure and exercise-related energy utilization in treated CeD patients compared to patients with other gastrointestinal (GI) conditions.

Methods

Adult patients attending the Celiac and Nutrition Clinic at McMaster University that underwent rest and exercise testing as a part of their nutritional assessment were enrolled. CeD diagnosis was based on positive CeD serology and confirmed by biopsy, and all of them were on a GFD for at least 6 months. Patients with inflammatory bowel disease (IBD), functional gastrointestinal disorders (FGID) and undernutrition due to other causes (UN) were included as controls. Resting energy expenditure was assessed using 3

methods

1) predictive formula (25kcal/kg), 2) Harris Benedict and 3) estimation of VO2 by IC. Exercise capacity and energy expenditure (EE) during exercise was estimated at baseline, moderate and maximum exercise. Statistical analysis was performed using SPSS. ANOVA with Bonferroni corrections and Chi2 test were used to assess differences between continuous and categorical variables, respectively.

Results

A total of 66 patients (CeD n=24; IBD n=15; FGID n=17; UN n=10) were included in the analysis. The REE of GI patients measured using the HB equation and the predictive formula were significantly underestimated compared to IC [Mean Difference (MD)=229 kcal/day p=0.03 and MD=365 kcal/day p<0.001, respectively]. The EE during exercise increased with intensity of exercise. CeD patients had the highest EE during moderate and strenuous exercise (Mean EE = 286 kcal/h and 494 kcal/h respectively) compared to patients with other GI conditions (Moderate and Strenuous for IBD= 218kcal/h and 373kcal/h; for FGIDs 296kcal/hand 467kcal/h, for UN, Mean EE = 181kcal/h and 294kcal/h). Exercise capacity was reduced in CeD compared to predicted exercise capacity (Mean = 86% predicted work capacity, range 72.5–107%), but was significantly higher than IBD (86% vs 73%; p=0.65) and UN patients (86% vs 46%; p=0.004).

Conclusions

Increased energy consumption and reduced exercise capacity is suggestive of chronic impaired nutritional status in treated CeD patients. Future studies with larger sample sizes are needed to understand whether incorporating accurate estimations of energy expenditure in nutritional practices can improve CeD outcomes.

Funding Agencies

CAG

A194 THE ADDITION OF DEAMIDATED GLIADIN PEPTIDE TO TISSUE TRANSGLUTAMINASE ANTIBODIES DOES NOT INCREASE THE ODDS OF CELIAC DISEASE DIAGNOSIS IN AN IGA SUFFICIENT POPULATION

Background

Previous studies proposed that the combination of IgA anti-tissue transglutaminase 2 IgA (TTG) and IgG deamidated gliadin peptide IgG (DGP) antibodies increases celiac disease (CeD) detection rates. However, this remains controversial.

Aims

To evaluate the performance of adding DGP to TTG antibodies, for the diagnosis of celiac disease (CeD) in the immunoglobulin A (IgA)-sufficient population.

Methods

We included consecutive patients with suspected CeD who had both TTG and DGP serology performed simultaneously from 2017–2020 in Hamilton, Canada. Chart review was performed by 3 reviewers to extract data on biopsies, diagnosis of CeD and genetic HLA-DQ2/DQ8. CeD was defined as positive serology (either TTG and/or DGP) and villous atrophy in duodenal biopsies (≥Marsh-3a). A case was defined as an instance of TTG and DGP performed at a single timepoint. A single patient could have represented multiple cases if TTG and DGP were measured at multiple time points. Sensitivity, specificity, negative and positive predictive values were calculated, and ROC curves were generated. Diagnostic odds ratios (DOR) assessed the performance of each serological strategy compared to duodenal biopsies.

Results

There were 580 patients constituting 823 cases that met inclusion criteria, of whom 441 had CeD. IgA-deficient patients (n=100) were excluded. Of the 723 cases remaining, 337 (214 adult;123 pediatric) had serology performed at the time of CeD diagnosis. TTG increased the odds of CeD diagnosis compared with DGP, Diagnostic Odds Ratio (DOR)=53.22 (95% CI 22.63–119.80) vs DOR=21.28 (95% CI 10.67–42.46). The addition of DGP to TTG did not increase the odds of CeD diagnosis [DGP+TTG DOR=51.39 (95% CI 19.36–135.61) vs TTG alone DOR=53.22 (95% CI 22.63–119.80)]. There were 37 discordant cases where only one of either TTG or DGP was positive. HLA-DQ2/DQ8 were absent in 2/9 cases with isolated increased DGP. Among the discordant cases, TTG outperformed DGP (DOR TTG= 4.29; 95% CI 1.09–16.83 vs DOR DGP=0.23; 95% CI 0.06–0.92).

Conclusions

In the IgA-sufficient population, the addition of DGP to TTG testing does not increase the diagnostic accuracy of CeD serologic screening. This has implications in health-care costs as false positive results prompt further investigations. Given these findings, larger prospective studies should be completed prior to adding DGP antibodies to routine TTG serology.

Funding Agencies

None

Au nanoparticles decorated polypyrrole-carbon black/g-C3N4 nanocomposite as ultrafast and efficient visible light photocatalyst

Modification and bandgap engineering are proposed to be extremely significant in improving the photocatalytic activity of novel photocatalysts. The current research focused on the fabrication of ultrafast and efficient visible light-responsive ternary photocatalyst containing g-C₃N₄ nanostructures in conjugation with polypyrrole doped carbon black (PPy-C) and gold (Au) nanoparticles by highly effectual, simple, and straightforward methodology. Various analytical techniques like XRD, FESEM, TEM, XPS, FTIR, and UV-Vis spectroscopy were applied for characterization purposes. The XRD and XPS results confirmed the successful creation of a nanocomposite framework among Au, PPy-C and g-C₃N₄. The TEM images revealed that bare g-C₃N₄ holds sheets or layered graphitic structure with sizes ranging from 100 to 300 nm. The sponge-like PPy-C network intermingled perfectly with g-C₃N₄ sheets along with homogeneously distributed 5-15 nm Au nanoparticles. The band gap energy (E_g) for bare g-C₃N₄, PPy-C/g-C₃N₄ and Au@PPy-C/g-C₃N₄ nanocomposites were found to be 2.74, 2.68, and 2.60 eV, respectively. The photocatalytic activity for all newly designed photocatalysts have been assessed during the degradation of insecticide Imidacloprid and methylene blue (MB) dye, where Au@PPy-C/C₃N₄ was found to be extremely efficient with ultrafast removal of both imidacloprid and MB in just 25 min of visible light irradiation. It was revealed that the Au@PPy-C/g-C₃N₄ ternary photocatalyst removed 96.0% of target analyte imidacloprid, which is ⁓ 2.91 times more efficient than bare g-C₃N₄ in treating imidacloprid. This report provides a distinctly promising, highly effectual and straightforward route to destruct extremely toxic and notorious pollutants and opens a new gateway in the present challenging scenario of environmental concerns.

The new challenge of partial oxidation of methane over Fe2O3/NaY and Fe3O4/NaY heterogeneous catalysts

As one of the most important gases that abundantly contribute to air pollution, methane becomes the most leading gas that challenges researchers to utilize it in more functional products such as methanol. In this study, the conversion process involved iron oxide species supported by sodium Y (NaY-Z) zeolite as the catalysts. This work highlighted the preparation of Fe₂O₃ and Fe₃O₄ modified NaY zeolite to investigate their catalytic performance on partial oxidation of methane to methanol, with trace amount of oxygen (0.5% in N₂), in a batch reactor. The as-prepared catalysts were characterized using FTIR, XRD, SEM, and BET. The structure of NaY zeolite and its modified catalysts were confirmed. The pristine NaY-Z shows the highest activity followed by Fe₂O₃/NaY-3.52 (3.52 wt% of Fe loading) with high selectivity to formaldehyde (80%). Very high selectivity (∼100%) towards methanol was observed in the reactions on Fe₂O₃/NaY-1.70 and Fe₃O₄/NaY-2.55 catalysts, although the total amount of product was decreased. It was noticeable that Fe₃O₄/NaY-3.22 is an active catalyst and has good selectivity to methanol (70%).

Immersion-plated palladium nanoparticles onto meso-porous silicon layer as novel SERS substrate for sensitive detection of imidacloprid pesticide

Herein, we demonstrate the effectiveness of surface-enhanced Raman scattering (SERS) to detect trace concentration of potentially harmful imidacloprid pesticide. To achieve this ultimate objective, a rapid and highly effective methodology for the fabrication of active and stable porous silicon (PSi) plated palladium nanoparticles (PdNPs) SERS substrates by an electrochemical anodization and immersion plating routes was applied. The PSi layers were fabricated by the electrochemical anodization of a silicon wafer in ethanoic fluoride solution, followed by uniformly deposition of PdNPs via a simple immersion plating technique. The structural features and morphology of fabricated frameworks of PSi-Pd NPs have been investigated by field emission scanning electron microscopy (FE-SEM) with energy dispersive X-ray (EDX), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FT-IR) spectra. The PSi substrate demonstrates a meso-porous morphology with good distribution, good pore density and average pore sizes around 20 nm. The SERS performance of Si-Pd NPs and PSi-Pd NPs substrates has been examined taking imidacloprid (an insecticide) as a target analyte. The SERS signal of imidacloprid using PSi-Pd NPs substrate exhibited immense enhancement compared to the Si-Pd NPs substrate. The active substrate revealed excellent detectable performance with a concentration as low as 10^-9 M imidacloprid and an enhancement factor (EF) of 1.2 × 10⁵. This large EF is fundamentally ascribed to the combined effect of the electromagnetic improvement and charge transfer mechanisms. Additionally, no aging effect was observed for the present substrates kept in air for two weeks. Striking enhancement in Raman spectral signals obtained with the current PSi-Pd NPs substrates can provide a simple and smooth platform towards the sensitive detection of various target analytes.

Ultrasound Diagnosis and Active Ureteroscopy for Obstructive Ureteral Calculi during Pregnancy: Multicenter Experience

Objectives: To evaluate the safety and efficacy of ultrasound (US) and primary ureteroscopy (URS) in the management of symptomatic obstructive ureteric stones during pregnancy. Patients and Methods: A prospective multicenter study was performed between June 2013 and December 2019, including all consecutive pregnant patients admitted to three urology centers with intractable renal colic with obstructed ureter secondary to obstructive ureteral calculi. Color Doppler ultrasound was used to evaluate renal Resistive Index (RI) and ureter jet. Primary URS was performed to remove the blocking stones. The safety and effectiveness of the procedures were assessed, as well as the stone-free rate (SFR) and the condition of the upper tract after delivery. Results: A total of 111 pregnant patients were included with a mean age of 27.4 ± 4.4 years and a mean renal RI of 0.78 ± 0.02. US diagnosed stones in 46.8% of patients, while 100 (90%) patients had altered lower ureter urinary jet, including 86.5% who had URS-confirmed ureteric stones; SFR was 95.8% with no serious urologic, fetal, or obstetric complications. Nine percent of patients had premature delivery, which was significantly correlated with postoperative urinary tract infection and premature uterine contraction (p ˂ 0.0001). In the third-month follow-up of US, all patients showed no residual hydronephrosis. Postoperative follow-up procedures were required in 15.3% of patients. Conclusion: Obstructive ureteral stones during pregnancy can be detected safely and appropriately with a combined elevated renal RI and absent ureteral jet detected by Doppler US. Definitive URS is an efficient and safe alternative option for those who fail in conservative management.

Gold nanoparticles plated porous silicon nanopowder for nonenzymatic voltammetric detection of hydrogen peroxide

A voltammetric approach was developed for the selective and sensitive determination of hydrogen peroxide using Au plated porous silicon (PSi) nanopowder modified glassy carbon electrode (GCE). The AuNPs-PSi hybrid structure was synthesized via stain etching procedure followed by an immersion plating method to deposit AuNPs onto PSi via a simple galvanic displacement reaction with no external reducing agent to convert Au³⁺ to Au⁰. The as-fabricated AuNPs-PSi catalyst was successfully characterized by XRD, Raman, FTIR, XPS, SEM, TEM and EDS techniques. Well crystalline nature of the as-fabricated hybrid structure with AuNPs size ranging from 5 to 40 nm was observed. The specific surface area and total pore volume for both PSi and AuNPs plated PSi were evaluated using N₂ adsorption isotherm technique. Cyclic voltammetry and electrochemical impedance spectroscopy techniques were applied to investigate the catalytic efficiency of AuNPs-PSi modified electrode compared to pure PSi/GCE and unmodified GCE. The sensing performance of the active material modified GCE was thoroughly examined with linear sweep voltammetry (LSV) and square wave voltammetry (SWV) techniques. The AuNPs-PSi/GCE exhibited a remarkable linear dynamic range between 2.0 and 13.81 mM (for LSV) and 0.5-6.91 mM for (SWV) with high sensitivity and low detection limit of 10.65 μAmM^-1cm^-2 and 14.84 μM for LSV, whereas 10.41 μAmM^-1cm^-2 and 15.16 μM using SWV techniques, respectively. The fabricated sensor electrode showed excellent anti-interfering ability in the presence of several common biomolecules as well as demonstrated good operational stability and reproducibility with low relative standard deviation. Moreover, the modified electrode showed acceptable recovery of H₂O₂ in a real sample analysis. Thus, the developed AuNPs-PSi hybrid nanomaterial represents an excellent electrocatalyst for the efficient detection and quantification of H₂O₂ by the electrochemical approach.

[Bone marrow fibrosis in primary myelofibrosis in relation to myelodysplasia- and age-related mutations of hematopoietic cells]

Besides histopathological findings, there are no indicators of increased risk for fibrotic progression in myeloproliferative neoplasms (MPNs). Age-related clonal hematopoiesis (ARCH) or clonal hematopoiesis of indetermined potential (CHIP) are frequent findings in the elderly and combinations with MPN driver mutations (JAK2, MPL, and CALR) have been described. To determine the impact of ARCH/CHIP-related mutations for the development of fibrosis in primary myelofibrosis (PMF), the mutational status of cases with fibrotic progression from grade 0 to grade 2/3 (n = 77) as evidenced by follow-up bone marrow biopsies (median 6.2 years) was compared to prefibrotic PMF samples without the development of fibrosis (n = 27; median follow-up 7.3 years). Frequent ARCH/CHIP-associated mutations (TET2, ASXL1, DNMT3A) demonstrable at presentation were not connected with fibrotic progression. However, mutations that are rarely found in ARCH/CHIP (SRSF2, U2AF1, SF3B1, IDH1/2, and EZH2) were present in 24.7% of cases with later development of fibrosis and not detectable in cases staying free from fibrosis (P = 0.0028). Determination of tumor mutational burden (TMB) in a subgroup of cases (n = 32) did not show significant differences (7.68 mutations/MB vs. 6.85 mutations/MB). We conclude that mutations rarely found in ARCH/CHIP provide an independent risk factor for rapid fibrotic progression (median 2.0 years) when already manifest at first presentation.

Short-course modified regimen intrapleural alteplase and pulmozyme (DNase) in pleural infection

Pleural infection is a common clinical condition leading to hospitalisation. In the last decade, advances in pleural research have led to a paradigm shift in the treatment of complex effusion from a surgical approach to a less invasive non-surgical approach using a combination of intrapleural fibrinolytics and pulmozyme (DNase). We report 3 patients with pleural infection. Intercostal chest catheter failed to drain the complex effusion. They were subsequently treated with a modified short-course regimen of alteplase and DNase. They received 3 cycles of 16 mg alteplase with 5 mg DNase each within 24 hours and all three had a favourable outcome with no adverse effects. This modified regimen appears effective with good safety profile and adds to the current literature on the safety and effectiveness of different dose combinations of alteplase and DNase.

Doping Strontium into Neodymium Manganites Nanocomposites for Enhanced Visible light Driven Photocatalysis

Nd_1-xSr_xMnO₃ nanocomposites perovskites were synthesized using sol gel method at different Sr content x = 0.3, 0.5, 0.7, and 0.9. The photocatalytic performance of the Nd_1-xSr_xMnO₃ nanocomposites for photodegradation of Acridine orange dye (AO) was evaluated over visible light illumination. The single phase of orthorhombic pbnm was formed for x = 0.3 and 0.5; however monoclinic and orthorhombic were observed at x = 0.7 and 0.9. The Energy gap of the Nd_1-xSr_xMnO₃ nanocomposites were estimated for all concentrations to be in the range of 3 ± 0.05 eV. The photocatalytic efficiency of Nd_0.3Sr_0.7MnO₃ nanocomposite was 95% of the initial AO dye concentration within 3 h illumination time. The linear increase of the photodegradation rate was found in our samples as a result of the increase of Sr contents from 0.3 to 0.7wt %. Interestingly, the Nd_0.3Sr_0.7MnO₃ content has the highest degradation rate of AO which is two times faster than undoped NdMnO₃. This superior behavior in photocatalytic activity of Nd_0.3Sr_0.7MnO₃ nanocomposite emerges from large surface area, structural anisotropy, and small particle size. These findings shows convincingly that the Nd_1-xSr_xMnO₃ photocatalysts possess great promise for visible light driven photodegradation of AO dye.

A review on methodologies for extraction, identification and quantification of allergenic proteins in prawns

Prawn allergy is one of the most common food-borne allergies and current prevention is by avoidance. This review paper summarised different methodologies for the extraction, identification and quantification of prawn protein allergens, reported in various research studies. Following extraction, allergenic components have been analysed using well-established methodologies, such as SDS-PAGE, Immunoblotting, ELISA, CD Spectroscopy, HPLC, DBPCFC, SPT etc. Moreover, the preference towards Aptamer-based technique for allergenicity analysis has also been highlighted in this review paper. The summary of these methodologies will provide a reference platform for present and future research directions.

Development, progress and future prospects in cryobiotechnology of Lilium spp

Lilium is one of the most popular flower crops worldwide, and some species are also used as vegetables and medicines. The availability of and easy access to diverse Lilium genetic resources are essential for plant genetic improvements. Cryopreservation is currently considered as an ideal means for the long-term preservation of plant germplasm. Over the last two decades, great efforts have been exerted in studies of Lilium cryopreservation and progress has been made in the successful cryopreservation of pollen, seeds and shoot tips in Lilium. Genes that exist in Lilium, including those that regulate flower shape, color and size, and that are resistant to cold stress and diseases caused by fungi and viruses, provide a rich source of valuable genetic resources for breeding programs to create novel cultivars required by the global floriculture and ornamental markets. Successful cryopreservation of Lilium spp. is a way to preserve these valuable genes. The present study provides updated and comprehensive information about the development of techniques that have advanced Lilium cryopreservation. Further ideas are proposed to better direct future studies on Lilium cryobiotechnology.

The battle of two ions: Ca2+ signalling against Na+ stress

Soil salinity adversely affects plant growth, crop yield and the composition of ecosystems. Salinity stress impacts plants by combined effects of Na⁺ toxicity and osmotic perturbation. Plants have evolved elaborate mechanisms to counteract the detrimental consequences of salinity. Here we reflect on recent advances in our understanding of plant salt tolerance mechanisms. We discuss the embedding of the salt tolerance-mediating SOS pathway in plant hormonal and developmental adaptation. Moreover, we review newly accumulating evidence indicating a crucial role of a transpiration-dependent salinity tolerance pathway, that is centred around the function of the NADPH oxidase RBOHF and its role in endodermal and Casparian strip differentiation. Together, these data suggest a unifying and coordinating role for Ca²⁺ signalling in combating salinity stress at the cellular and organismal level.

Analysis of beta-lactamases, blaNDM-1phylogeny & plasmid replicons in multidrug-resistant Klebsiella spp. from a tertiary care centre in south India

Background & objectives:

β-lactamases play a predominant role in drug-resistance amongst Enterobacteriaceae. Presence of genes on transferable plasmids encoding these enzymes favours their dissemination across species and genera within and outside geographical boundaries. This study was aimed to understand the presence of β-lactamases and transferable plasmids in clinical isolates of Klebsiella spp. which can contribute to the spread of resistance determinants.

Methods:

A total of 41 clinical isolates of Klebsiella spp., collected from a tertiary care centre in Kerala, India, were checked for antibiotic sensitivity and the presence of plasmids. The ability to produce extended-spectrum β-lactamases (ESBLs) and metallo-β-lactamases (MBLs) was screened for and confirmed in 29 plasmid-harbouring isolates. bla_NDM-1-specific primers were used for polymerase chain reaction amplification with plasmid DNA as template to determine episomal prevalence of this gene and its sequence-based phylogeny employing similar sequences from GenBank. Plasmid replicon typing was also carried out to determine the presence of transferable plasmids.

Results:

Our results showed a high degree of multidrug-resistant (MDR) pathogens with ESBL production confirmed in 52 per cent, MBL in 31 per cent and co-production of both enzymes in seven per cent of the plasmid-bearing isolates. Plasmid DNA from 14 per cent of the isolates produced bla_NDM-1-specific amplicons which showed sequence homology with those from bacteria of different genera and geographical areas. The predominant replicon type was found to be that of conjugative plasmids belonging to the incompatibility group - IncFII_K.

Interpretation & conclusions:

This study provides insight into the predominance of various β-lactamases and potent gene-disseminating agents in Klebsiella spp. and emphasizes the need for constant surveillance of these pathogens to determine appropriate treatment strategies.

Highly Sensitive Ethanol Chemical Sensor Based on Novel Ag-Doped Mesoporous α-Fe2O3 Prepared by Modified Sol-Gel Process

Mesoporous α-Fe₂O₃ has been synthesized via a simple sol-gel procedure in the presence of Pluronic (F-127) triblock copolymer as structure directing agent. Silver (Ag) nanoparticles were deposited onto α-Fe₂O₃ matrix by the photochemical reduction approach. Morphological analysis revealed the formation of Ag nanoparticles with small sizes < 20 nm onto the mesoporous structure of α-Fe₂O₃ possessing < 50 nm semi-spherical shape. The XRD, FTIR, Raman, UV-vis, PL, and N₂ sorption isotherm studies confirmed the high crystallinity, mesoporosity, and optical characteristics of the synthesized product. The electrochemical sensing toward liquid ethanol has been performed using the current devolved Ag/α-Fe₂O₃-modified glassy carbon electrode (GCE) by cyclic voltammetry (CV) and current potential (I-V) techniques, and the obtained results were compared with bare GCE or pure α-Fe₂O₃. Mesoporous Ag/α-Fe₂O₃ was found to largely enhance the sensor sensitivity and it exhibited excellent sensing characteristics during the precision detection of low concentrations of ethanol. High and reproducible sensitivity of 41.27 μAmM^- 1 cm^- 2 at lower ethanol concentration region (0.05 to 0.8 mM) and 2.93 μAmM^- 1 cm^- 2 at higher concentration zone (0.8 to 15 mM), with a limit of detection (LOD) of 15.4 μM have been achieved. Investigation on reaction kinetics revealed a characteristic behavior of mixed surface and diffusion-controlled processes. Detailed sensing studies revealed also that the sensitivity toward ethanol was higher than that of methanol or isopropanol. With further effort in developing the synthesis and fabrication approaches, a proper utility for the current proposed protocol for fabricating a better sensor device performance is possible.