Investigation of the Mechanical and Liquid Absorption Properties of a Rice Straw-Based Composite for Ayurvedic Treatment Tables

Managing rice crop stubble is one of the major challenges witnessed in the agricultural sector. This work attempts to investigate the physical, mechanical, and liquid absorption properties of rice straw (RS)-reinforced polymer composite for assessing its suitability to use as an ayurvedic treatment table. This material is expected to be an alternative for wooden-based ayurvedic treatment tables. The results showed that the addition of rice straw particles (RSp) up to 60% volume in epoxy reduced the density of the composite material by 46.20% and the hardness by 15.69%. The maximum tensile and flexural strength of the RSp composite was 17.53 MPa and 43.23 MPa, respectively. The scanning electron microscopy (SEM) analysis showed deposits of silica in the form of phytoliths in various size and shapes on the outer surface of RS. The study also revealed that the water absorption rate (WA) was less than 7.8% for the test samples with 45% volume of RSp. Interestingly the test samples showed greater resistance to the absorption of Kottakal Dhanvantaram Thailam (<2%). In addition, the developed samples showed resistance towards bacterial and fungal growth under the exposure of treatment oils and water.

Measurement of Neutron Dose Equivalent within and Outside of a LINAC Treatment Vault Using a Neutron Survey Meter

This work concerns neutron doses associated with the use of a Siemens Primus M5497 electron accelerator, which is operated in the photon mode at 15 MV. The conditions offer a situation within which a fraction of the bremsstrahlung emission energies exceed the photoneutron threshold. For different field sizes, an investigation has been made of neutron dose equivalent values at various measurement locations, including: (i) At the treatment table, at a source-surface distance of 100 cm; (ii) at the level of the floor directly adjacent to the treatment table; and (iii) in the control room and patient waiting area. The evaluated neutron dose equivalent was found to range from 0.0001 to 8.6 mSv/h, notably with the greatest value at the level of the floor directly adjacent to the treatment couch (8.6 mSv/h) exceeding the greatest value on the treatment table (5.5 mSv/h). Low values ranging from unobservable to between 0.0001 to 0.0002 mSv/h neutron dose were recorded around the control room and patient waiting area. For measurements on the floor, the study showed the dose equivalent to be greatest with the jaws closed. These data, most particularly concerning neutron distribution within the treatment room, are of great importance in making steps towards improving patient safety via the provision of protective measures.

Oxygen toxicity seizures during United States Navy Treatment Table 6: An acceptable risk in monoplace chambers?

Introduction: Hyperbaric oxygen treatment (HBOT) may be complicated by oxygen toxicity seizures, which typically occur with hyperbaric partial pressures of oxygen exceeding 203 kPa (2 atmospheres absolute). All other hyperbaric units in Australia exclusively use a multiplace chamber when treating with United States Navy Treatment Table 6 (USN TT6) due to this perceived risk. The purpose of this study was to determine the safety of a monoplace chamber when treating decompression illness (DCI) with USN TT6. Methods: A retrospective review of the medical records of all patients treated at Fiona Stanley Hospital Hyperbaric Medicine Unit with USN TT6 between November 2014 and June 2020 was undertaken. These data were combined with previous results from studies performed at our hyperbaric unit at Fremantle Hospital from 1989 to 2014, creating a data set covering a 30-year period. Results: One thousand treatments with USN TT6 were performed between 1989 and 2020; 331 in a monoplace chamber and 669 in a multiplace chamber. Four seizures occurred: a rate of 0.59% (1/167) in a multiplace chamber; and none in a monoplace chamber, indicating no statistically significant difference between seizures in a monoplace versus multiplace chamber (P = 0.31). Conclusions: The rate of oxygen toxicity seizures in a monoplace chamber is not significantly higher than for treatment in the multiplace chamber. We conclude that using the monoplace chamber for USN TT6 in selected patients poses an acceptably low seizure risk.

POS0465 DIFFERENT CLINICAL RELEVANCE OF ANTI-CITRULLINATED PROTEINS ANTIBODIES IN RA PATIENTS

Background:Anti-citrullinated proteins antibodies (ACPA) are a broad group of antibodies, including antibodies to citrullinated fibrinogen, antibodies to cyclic citrullinated peptide (anti-CCP), antibodies to modified citrullinated vimentin (anti-MCV), antibodies to citrullinated α-enolase.Objectives:To find a potential relationship between ACPA and disease activity, bone destruction, and ACPAs responses to various therapeutic regimens.Methods:The study included 232 patients (pts) with rheumatoid arthritis (RA); 90 pts (74 women, Me;IQR age 53.0 (38.0–58.5) years had early RA, with mean disease duration 5.0 (4.0–9.0) months, DAS 28 5.3 (4.4–6.1)); 142 pts had advanced stage of the disease (123 women, median age 51.0 (43.0–60.0) years, disease duration 56.0 (24.0–96.0) months, DAS 28 6.2 (5.5–6.8)). Pts with early RA received methotrexate (MTX) subcutaneously at average 17.5 mg dose once weekly. Pts with advanced RA received the following anti-B-cell therapy: 34 pts - rituximab (RTX); 20 pts - RTX biosimilar; 43 pts - tocilizumab (TCZ) in combination with conventional DMARDs. Serum anti-CCP and anti-MCV concentrations were measured using ELISA.Results:77 (85.6%) pts with early RA were high positive for anti-CCP, and 29 (70.7%) pts - high positive for anti-MCV. A positive correlation was found between anti-MCV and DAS 28 (r=0.4, p=0.04). As for advanced RA, 78 (80.4%) pts were high positive for anti-CCP, and 70 (79.5%) - for anti-MCV. There was a positive correlation between anti-MCV concentration and SDAI (r=0.4, p=0.02), as well as CDAI (r=0.4, p=0.02). No significant correlations were found between the anti-CCP levels and activity indices, anti-CCP and acute-phase parameters in both early and advanced RA groups. Higher total Sharp scores (96.5 (65.0-122.0)) were found in pts high positive for anti-MCV (n=79), compared to low-positive/negative (57.0 (31.0–88.0), respectively, (n=27, p<0.05). anti-MCV levels dropped significantly in pts on RTX and TCZ therapy at weeks 12 and 24 after initiation of treatment, while high anti-CCP concentration persisted throughout the treatment (Table 1)Conclusion:anti-MCV levels correlated with inflammatory activity and development of bone destruction, and were decreasing in pts on treatment. Anti-CCP was less responsive, showed minor changes during treatment, therefore its’ thorough monitoring was not feasible.Disclosure of Interests:None declared

MR-Guided Radiotherapy for Rectal Cancer: Current Perspective on Organ Preservation

Online MRI-guided radiotherapy (MRgRT) is one of the most recent technological advances in radiotherapy. MRgRT permits the visualization of tumorous and healthy tissue while the patient is on the treatment table and online daily plan adaptations following the observed anatomical changes. In the context of rectal cancer, online MRgRT is a very promising modality due to the pronounced geographical variability of tumor tissues and the surrounding healthy tissues. This current paper will discuss the possible applications of online MRgRT, in particular, in terms of radiotherapy dose escalation and response prediction in organ preservation approaches for rectal cancer.

Association of cabozantinib residual concentration (Ctrough) and blood clearance (Cl/F) with toxicity (tox) and progressive disease (PD) in metastatic renal cell carcinoma (mRCC) patients (pts): Results from a monocentric pharmacokinetics (PK) study.

292 Background: Cabozantinib is a TKI with a substantial efficacy in mRCC. It is associated with a relevant tox leading frequent dose modifications (DM) or drug discontinuations (DD). While an exposure/safety relation has been demonstrated for this drug, an exposure/efficacy relation is still unknown. Cl/F is a measure of elimination of a drug from blood or plasma and lower Cl/F of cabozantinib has been previously associated with increased DM rate in mRCC. Methods: We performed a monocentric PK (INDS MR 5612140520) study in patients with mRCC. Blood draw for assessment of cabozantinib PK was performed at least 8 hours from the last drug dose. Ctrough was estimated with the following equation: Ctrough=Cmeas*0,5DI-24/t1/2. Ctrough and Cl/F were compared in patients with or without a relevant tox and in PD pts vs SD/PR pts. Relevant tox was defined either as G3-4 tox or G2 tox leading to DM or DD. Differences in Ctrough and CL were assessed between the groups with Mann Withney U test. Results: From 01.10.19 to 31.08.20 66 pts were included in this analysis. Twenty one relevant tox and 29 PD were observed. Ctrough was higher in pts experiencing relevant tox than in those who did not: 624,6 ng/ml (IQR 494-1030,2 ng/ml) vs 505,2 ng/ml (IQR 329,2-910,2), p0.012. Conversely Cl/F was lower in relevant tox vs not tox1,85 l/h (IQR 1,4-2,2 l/h) vs 2.27 l/h (IQR 1,7-3,2), p 0.024. In PD pts, Ctrough was lower than in SD/PR pts: 419ng/ml (IQR 317,2 -549,1 ng/ml) vs 554 ng/ml (IQR 416,9-795,6), p 0.0105, while Cl/F was higher in PD patients: 2,6 l/h (IQR 2,14-3,44 l/h) vs SD/PR patients 1.9 l/h (1,930 l/h;IQR 1,35-2,53 l/h); p= 0.011. Time from day cycle 1 to PK blood draw was significatively longer in non-tox pts and numerically longer in PD pts, which have the lowest Ctrough and the highest Cl/F. Conclusions: Cabozantinib toxicity is associated to a higher Ctrough and a lower Cl/F. Cabozantinib PD is associated to a lower Ctrough and a higher Cl/F. Cl/F should be assessed alongside with Ctrough in Cabozantinib PK blood test; Ctrough may decrease and conversely Cl/F may increase with time on treatment. [Table: see text]