Improvement in Dysphagia Outcomes Following Clinical Target Volume Reduction in the De-ESCALaTE Study

AIMS

The De-ESCALaTE study showed an overall survival advantage for the administration of synchronous cisplatin chemotherapy with radiotherapy in low-risk oropharyngeal cancer when compared with synchronous cetuximab. During the trial, a radiotherapy quality assurance protocol amendment permitted centres to swap from the original radiotherapy contouring protocol (incorporating the whole oropharynx into the high-dose clinical target volume (CTV); anatomical protocol) to a protocol that incorporated the gross tumour volume with a 10 mm margin into the CTV (volumetric protocol). The purpose of this study was to examine both toxicity and tumour control related to this protocol amendment.

MATERIALS AND METHODS

Overall survival and recurrence at 2 years were used to compare tumour control in the two contouring cohorts. For toxicity, the cohorts were compared by both the number of severe (grades 3-5) and all grades acute and late toxicities. In addition, quality of life and swallowing were compared using EORTC-C30 and MD Anderson Dysphagia Inventory, respectively.

RESULTS

Of 327 patients included in this study, 185 were contoured according to the anatomical protocol and 142 by the volumetric protocol. The two cohorts were well balanced, with the exception of significantly more patients in the anatomical cohort undergoing prophylactic feeding tube insertion (P < 0.001). With a minimum of 2 years of follow-up there was no significant difference in overall survival or recurrence between the two contouring protocols. Similarly, there was no significant difference in the rate of reported severe or all grades acute or late toxicity and no sustained significant difference in quality of life. However, there was a significant difference in favour of volumetric contouring in several domains of the MD Anderson Dysphagia Inventory questionnaire at 1 year, which persisted to 2 years in the dysphagia functional (P = 0.002), dysphagia physical (P = 0.009) and dysphagia overall function (P = 0.008) domains.

CONCLUSION

In the context of the unplanned post-hoc analysis of a randomised trial, measurable improvement in long-term dysphagia has been shown following a reduction in the CTV. Further reductions in the CTV should be subject to similar scrutiny within the confines of a prospective study.

18F-FDG-PET in guided dose-painting with intensity modulated radiotherapy in oropharyngeal tumours: A phase I study (FiGaRO)

BACKGROUND AND PURPOSE

The FiGaRO trial assessed the feasibility and safety of using an FDG-PET-based dose-painting technique to deliver a radiotherapy (RT) boostto the FDG-avid primary tumour in patients with locally advanced high and intermediate risk oropharyngeal cancer.

MATERIALS AND METHOD

Patients underwent a planning 18FDG-PET-CT scan, immobilised in the treatment position, after one cycle of induction chemotherapy. The volume of persistent FDG-avidity in the primary tumour was escalated to 71.5 Gy in30 fractions delivered using a simultaneous integrated boost Intensity Modulated RT (SIB-IMRT) technique. RT was delivered with concomitant Cisplatin following 2 cycles of induction chemotherapy. The primary outcome was the incidence of grade ≥ 3 late mucosal toxicity 12 months post-treatment, with an excess rate of >10% regarded as unacceptable.

RESULTS

Twenty-nine patients were included and twenty-four were treated between 2014 and 2018, in two UK centres. Median follow-up was 36 months (range 4-56 months). Pre-defined planning target volume objectives and organ at risk dose constraints were met in all cases. There were no incidents of acute grade 4 toxicity. There were 4 cases of grade ≥ 3 mucosal toxicity at 12 months post-treatment (19.1%). There were no cases of persistent mucosal ulceration at 12 months. Overall survival at 3-years was 87.5%, 92.9% for intermediate and 70.0% for high risk patients.

CONCLUSION

Late toxicity rates, although higher than anticipated, are comparable to contemporary published data for standard dose chemo-IMRT. Results suggest improved 3y survival rates for high risk patients. This approach merits further investigation. ClinicalTrials.gov Identifier: NCT02953197.

Experimental and DFT studies of porous carbon covalently functionalized by polyaniline as a corrosion inhibition barrier on nickel-based alloys in acidic media

In acidic medium, nickel alloys severely suffer from long term corrosion problems as a result of the breakdown of their passivating oxide. The present study considers polyaniline functionalized fish-scale graphitic carbon as an anticorrosion coating on the nickel alloy surface. The fish-scale porous carbon materials are characterized by XRD, ATR-FITR, UV, Raman, TGA, SS NMR, FESEM, and TEM methods. The surface of the alloy is covalently bound with a polyaniline long chain protonated polymer so that the polyaniline functionalized honeycomb fish-scale carbon structure can exchange electrons with the metal surface. The corrosion inhibition efficiency has been investigated in different acid media like sulfuric acid and hydrochloric acid by electrochemical methods. Polyaniline functionalized porous carbon showed in 1 M H₂SO₄ inhibition efficiency around 64% and in 1 M HCl inhibition efficiency was around 74%. The inhibition efficiency was higher in HCl because chloride ions were not able to penetrate the graphitic sheet. The novelty of this coating is in the fact that the polyaniline functionalized porous carbon has high conductivity and is electrochemically stable in acidic medium. It is able to donate electrons to the polarized metal surface.

Polyaniline functionalized fish scale carbon chemisorption on 111 nickel alloy surface by polyaniline polaron nitrogen free electron.

Experimental and DFT studies on the ultrasonic energy-assisted extraction of the phytochemicals of Catharanthus roseus as green corrosion inhibitors for mild steel in NaCl medium

Catharanthus roseus (Apocynaceae family) extract is rich in organic phytochemicals such as alkaloids, polyphenolic compounds, and flavonoids. It contains several functional entities such as fused heterocycles, and hydroxyl and carbonyl groups, which could be useful for corrosion inhibition of mild steel in NaCl environments. In the present work, ultrasonic energy was used to obtain the ethanolic extracts of root and stem which were then tested as corrosion inhibitors for mild steel in the presence of 3.5% NaCl. The corrosion inhibition process was studied by UV-visible spectroscopy, Fourier transform infrared spectroscopy, atomic force microscopy, weight loss, and electrochemical methods. After immersing in the corrosive medium, the microstructures of mild steel were investigated by scanning electron microscopy, X-ray diffraction, and ellipsometry. The extract of C. roseus showed excellent adsorption on mild steel surface as confirmed by DFT calculations. The results indicate that the extract of C. roseus acts as a mixed type corrosion inhibitor, where the stem extract is the most efficient inhibitor in 3.5% NaCl solution possibly due to the higher active area of stem phytochemicals.

C. roseus phytochemicals are physisorbed on the 111 Fe surface, and the oxygen non-bonding electron chemisorbed on the polarized state 111 Fe surface.

Experimental and computational studies of graphene oxide covalently functionalized by octylamine: electrochemical stability, hydrogen evolution, and corrosion inhibition of the AZ13 Mg alloy in 3.5% NaCl

Recently, carbon allotropes were shown to play a key role in energy harvesting and as hydrophobic coatings on metal alloys. We have designed octylamine-functionalized graphene oxide materials for energy harvesting and as an anti-corrosion coating for metal alloy protection in a 3.5% NaCl medium. The material has been characterized by different techniques to confirm the structure and composition of the modified graphene oxide sheet: FTIR spectroscopy, XRD, Raman spectroscopy, FESEM and TEM. The electrochemical stability and corrosion inhibition efficiency were studied by electrochemical methods. The electrochemical stability increased with an increase in the applied voltage up to 500 mV, and the corrosion inhibition efficiency was shown to be 73%. The coating stability studies showed a long stability time in the corrosion medium.

Octylamine-functionalized graphene oxide chemisorbed onto a Mg alloy surface by non-bonding electron.

Experimental and computational studies of a graphene oxide barrier layer covalently functionalized with amino acids on Mg AZ13 alloy in salt medium

Leucine functionalized graphene oxide chemisorbed on a 111 surface AZ13 magnesium alloy via edge functional groups.

Neodymium-decorated graphene oxide as a corrosion barrier layer on Ti6Al4V alloy in acidic medium

Neodymium-decorated graphene oxide is chemisorbed by non-bonding electrons on Ti6Al4V surface increasing the corrosion inhibition in acidic media.

Praseodymium-decorated graphene oxide as a corrosion inhibitor in acidic media for the magnesium AZ31 alloy

In the present work, Pr-decorated graphene oxide was synthesized and tested as a corrosion barrier layer in acidic media for the magnesium AZ31 alloy. The morphology, composition and structure of Pr-decorated graphene oxide sheets were characterized via HRTEM, FESEM, Raman, XRD, DLS, UV and FTIR studies. The corrosion inhibition efficiency on the alloy surface was monitored via microstructural and electrochemical methods. The results indicate that Pr-decorated graphene oxide provides improved protection for the Mg AZ31 alloy compared to conventional epoxy coatings. The proposed mechanism arises from a combination of the barrier activities of the composite, GO + Pr, and the epoxy coating on the Mg alloy in acidic media.

The Mg alloys 111 surface is covered by the praseodymium decorated graphene oxide sheet, and (A) & (B) indicates ions diffusion control (C) indicates epoxy coating failure.

Head and neck target delineation using a novel PET automatic segmentation algorithm

PURPOSE

To evaluate the feasibility and impact of using a novel advanced PET auto-segmentation method in Head and Neck (H&N) radiotherapy treatment (RT) planning.

METHODS

ATLAAS, Automatic decision Tree-based Learning Algorithm for Advanced Segmentation, previously developed and validated on pre-clinical data, was applied to ¹⁸F-FDG-PET/CT scans of 20 H&N patients undergoing Intensity Modulated Radiation Therapy. Primary Gross Tumour Volumes (GTVs) manually delineated on CT/MRI scans (GTVp_CT/MRI), together with ATLAAS-generated contours (GTVp_ATLAAS) were used to derive the RT planning GTV (GTVp_final). ATLAAS outlines were compared to CT/MRI and final GTVs qualitatively and quantitatively using a conformity metric.

RESULTS

The ATLAAS contours were found to be reliable and useful. The volume of GTVp_ATLAAS was smaller than GTVp_CT/MRI in 70% of the cases, with an average conformity index of 0.70. The information provided by ATLAAS was used to grow the GTVp_CT/MRI in 10 cases (up to 10.6mL) and to shrink the GTVp_CT/MRI in 7 cases (up to 12.3mL). ATLAAS provided complementary information to CT/MRI and GTVp_ATLAAS contributed to up to 33% of the final GTV volume across the patient cohort.

CONCLUSIONS

ATLAAS can deliver operator independent PET segmentation to augment clinical outlining using CT and MRI and could have utility in future clinical studies.

Ascariasis: challenges in the diagnosis of single worm disease

One of the most common parasitic infections in humans is ascariasis. While most infectionsare asymptomatic, mild to moderate symptoms may occur due to migration of adult worms. The frequency of single worm infection seems to be increasing. Ascaris eggs are not found in the faeces of most cases infected with a single worm because it is an immature male or female. Diagnosis of such single worm infection is challenging.

Seroprevalence of Toxoplasma gondii in southern districts of Tamil Nadu using IgG-ELISA

The present study was conducted to assess the seroprevalence of Toxoplasma gondii in and around Tirunelveli by in-house IgG assay using ELISA. Serum samples from 175 immunodeficient and 175 immunocompetent patients were collected at Tirunelveli district, Tamil Nadu from May 2006 to October 2007. They were subjected into in-house IgG assay using enzyme-linked immune sorbent assay (ELISA) in which tachyzoite soluble antigen derived from solubilised whole organisms was used. Out of 350 patients tested by IgG ELISA, 46 patients (13.14%) had antibodies for toxoplasmosis with mean OD value of 0.2 ± 0.073 and the OD value ranged from 0.144 to 0.444. Among the immunocompetent group of 175 patients, 19 patients (10.86%) had antibodies to toxoplasmosis whereas, in immunodeficient group of 175 patients, 27 patients (15.43%) had antibodies for toxoplasmosis. There was no statistical difference (P > 0.05) between the immunocompetent and immunodeficient group. The sensitivity and specificity of IgG ELISA in detecting toxoplasmosis was 90 and 100%, respectively. The overall seroprevalence of toxoplasmosis in and around Tirunelveli district of Tamil Nadu was 13.14% based on IgG ELISA. The study has proved ELISA to be a sensitive and specific procedure for the serodiagnosis of toxoplasmosis.

IgG--indirect fluorescent antibody technique to detect seroprevalence of Toxoplasma gondii in immunocompetent and immunodeficient patients in southern districts of Tamil Nadu

PURPOSE

The purpose of the study was to determine the prevalence of Toxoplasma antibodies in selected immunocompetent and immunodeficient patients in and around Tirunelveli District of Tamil Nadu.

MATERIALS AND METHODS

This study was carried out from May 2006 to October 2007 in 175 immunodeficient and 175 immunocompetent patients. Serum samples were subjected into in-house IgG assay using indirect fluorescent antibody test (IFAT).

RESULTS

Out of 350 patients tested by IgG IFAT, 41 (11.71%) had antibodies for Toxoplasma gondii with a mean IFA titre of 43.42 ± 58.7 and the titre ranging from 1 : 16 to 1 : 256. Among the immunocompetent and immunodeficient groups, 19 patients (10.86%) and 22 patients (12.57%), respectively, had antibodies to T. gondii. Various risk factors associated within the study group was analysed and results were interpreted.

CONCLUSIONS

The study has highlighted an overall seroprevalence of 11.71% with 12.57% in immunocompromised and 10.86% in immunocompetent patients respectively in a southern district, Tamil Nadu, which underlines the importance of screening of this parasite especially in the immunocompromised patients.

Relative prevalence of hepatitis B viral markers and hepatitis C virus antibodies (anti HCV) in Madurai, south India

(1) The positivity of HBsAg was 4% (75/1819) whereas anti HCV was present only in 0.75% (27/3574) of blood donors. (2) 5.3% (4/75) of hospital staff had HBsAg alone in their blood samples. One doctor, one Staff nurse, one Lascar and one Sanitary worker were positive for HBsAg. None of them were positive for anti HBcIgm and anti-HCV. (3) 29% (31/115) of suspected hepatitis cases were positive for any one of the viral markers or both. 21% (15/72) of males and 14% (6/43) of females were positive for HBsAg. Whereas only 4% (3/72) of males and 2% (1/43) of females were positive for anti HCW. Both HBsAg and anti HCV were found in 8% (6/72) of males only. The age group predominantly, i.e. in 29 out of 31 cases found positive for HBsAg and/or anti HCV, was above 15 years. Two remaining HBsAg positive cases belonged to the 5 to 14 years age group. 71% (84/115) of suspected hepatitis cases were negative for both HBsAg and anti HCV.