Percutaneous thermal ablation has proved to be an effective modality for treating both benign and malignant tumors in various tissues. Among these modalities, radiofrequency ablation (RFA) is the most promising and widely adopted approach that has been extensively studied in the past decades. Microwave ablation (MWA) is a newly emerging modality that is gaining rapid momentum due to its capability of inducing rapid heating and attaining larger ablation volumes, and its lesser susceptibility to the heat sink effects as compared to RFA. Although the goal of both these therapies is to attain cell death in the target tissue by virtue of heating above 50 o C, their underlying mechanism of action and principles greatly differs. Computational modelling is a powerful tool for studying the effect of electromagnetic interactions within the biological tissues and predicting the treatment outcomes during thermal ablative therapies. Such a priori estimation can assist the clinical practitioners during treatment planning with the goal of attaining successful tumor destruction and preservation of the surrounding healthy tissue and critical structures. This review provides current state-ofthe-art developments and associated challenges in the computational modelling of thermal ablative techniques, viz., RFA and MWA, as well as touch upon several promising avenues in the modelling of laser ablation, nanoparticles assisted magnetic hyperthermia and noninvasive RFA. The application of RFA in pain relief has been extensively reviewed from modelling point of view. Additionally, future directions have also been provided to improve these models for their successful translation and integration into the hospital work flow.

The results show that the surrounding tissue environment significantly affects the ablation volume produced during RFA. The optimal treatment time for complete tumour ablation can play a critical role in minimising the damage to the surrounding healthy tissue and ensuring safe and risk free application of RFA. The obtained results emphasise the need for developing organ-specific clinical protocols and systems during RFA of tumour.

Host cell interactions and invasion by Cryptosporidium is a complex process mediated by zoites ligand-host cell receptors. Knowledge of proteins involved in this process will enable entry level inhibitors to be tried as therapeutic agents. In the present study, invasion proteins of Cryptosporidium parvum were studied in vitro. Cryptosporidium sporozoites membrane proteins were isolated and Cy5 dye labelled. They were then allowed to interact with the intact host cells. The interacting proteins were identified using 2-dimensional gel electrophoresis followed by mass spectrometry analysis. Sixty-one proteins were identified including twenty-seven previously reported invasion proteins. The newly identified proteins such as serine/threonine protein kinase, PI4 kinase, Hsp105 and coiled coil may have their roles in the parasitic invasion process. Thus, a new approach was used in the study to identify the probable proteins involved in invasion and/or host-parasite interactions. The advantage of this method is that it takes only a months' time instead of decades to identify these proteins involved in invasion process.

Coupled thermo-electro-mechanical models for thermal ablation of biological tissues and heat relaxation time effects."

Stools from 28 of the 82 inhabitants on remote Little Andaman Island in India were examined for parasite eggs and cysts. Trichuris trichiura eggs were found in 27, Trichuris vulpis eggs in 5, Strongyloides stercoralis larvae in 3, hookworm eggs in 15, Entamoeba histolytica and Entamoeba coli cysts each in 9, Giardia lamblia in 6, Retortamonas sp. in 3, Iodoamoeba sp. in 2, and Chilomastix sp. in 2 stools. Ascaris lumbricoides eggs were not seen. The occurrence of T. vulpis eggs in 5 stools and the absence of A. lumbricoides eggs were considered unusual findings.

Microwave ablation (MWA) is a minimally invasive thermal treatment modality that has already evolved as a promising alternative to radiofrequency ablation for treating different types of malignant and benign tumors, especially ≥3 cm in diameter. The efficacy of thermal ablative therapies is mainly judged by the ablation volume attained post‐ablation. In this regards, the present study aims at analyzing the influence of six critical parameters, as follows, relative permittivity, electrical conductivity, volumetric heat capacity, thermal conductivity, blood perfusion rate, and applied power on the ablation volume attained during MWA. Taguchi's L27 orthogonal array has been adopted for the current problem with six input variables having three levels each. The electric and thermophysical properties considered in the study have been derived from liver, lung, breast, and kidney. Finite element method (FEM) based numerical simulations of MWA have been conducted on three‐dimensional homogeneous model of biological tissue using coaxial single slot microwave antenna. Further, the ranking and the contribution of each parameter on the ablation volume attained during MWA have been quantified using analysis of variance. The corollaries drawn from the study would be useful to the clinical practitioners during the treatment planning stage of the MWA.

The application of radiofrequency ablation (RFA) has been widely explored in treating various types of cardiac arrhythmias. Computational modeling provides a safe and viable alternative to ex vivo and in vivo experimental studies for quantifying the effects of different variables efficiently and reliably, apart from providing a priori estimates of the ablation volume attained during cardiac ablation procedures. In this contribution, we report a fully coupled electro-thermo-mechanical model for a more accurate prediction of the treatment outcomes during the radiofrequency cardiac ablation. A numerical model comprising of cardiac tissue and the cardiac chamber has been developed in which an electrode has been inserted perpendicular to the cardiac tissue to simulate actual clinical procedures. Temperature-dependent heat capacity, electrical and thermal conductivities, and blood perfusion rate have been considered to model more realistic scenarios. The effects of blood flow and contact force of the electrode tip on the treatment outcomes of a fully coupled model of RFA have been systematically investigated. The numerical study predicts that the predicted ablation volume of RFA is significantly dependent on the blood flow rate in the cardiac chamber, and also on the tissue deformation induced due to electrode insertion depth of 1.5 mm, or higher.

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