Focused microwave−hyperthermia therapy has recently emerged as a key technology in the treatment of breast cancer due to non−invasive treatment. An applicator of a three−ring phased array consisting of ultra−wideband (UWB) microstrip antennas was designed for breast cancer therapy and operates at 0.915 GHz and 2.45 GHz. The proposed antenna has an ultra−wideband from 0.7 GHz to 5.5 GHz with resonant frequencies of 0.915 GHz and 2.45 GHz and dimensions of 15 × 43.5 × 1.575 mm3. The number of each ring was chosen to be 12 based on the SAR distribution and the performance indicators of tumor off−center focusing results for four different numbers of single−ring arrays. The homogeneous breast model is applied to a three−ring phased array consisting of 36 elements for focused simulation, and 1 cm3 and 2 cm3 tumors are placed in three different locations in the breast. The simulation results show that the proposed phased array has good performance and the capability to raise the temperature of different volumes of breast cancer above 42.5 °C after choosing a suitable operating frequency. The proposed applicator allows for precise treatment of tumors by selecting the appropriate operating frequency based on the size of the malignant tumor.
Colorectal cancer (CRC) is a leading cause of cancer deaths worldwide. Aberrant regulation of DNA methylation in promoters of tumor suppressor genes or proto-oncogenes is one of the fundamental processes driving the initiation and progression of CRC. Zinc-finger proteins (ZNFs) are one of the most abundant groups of proteins and function in many important biological processes related to tumorigenesis. Herein, we detected abnormal hypermethylation of the ZNF334 gene in CRC tissues compared with normal tissues, and this modification downregulated the expression of ZNF334. Furthermore, ten-eleven translocation 1 (TET1) was identified to be involved in regulating the methylation level of ZNF334. Next, a dCas9-multiGCN4/scFv-TET1CD-sgZNF334-targeted demethylation system was constructed to reverse the expression of ZNF334 through sgRNA targeting the ZNF334 promoter. Both in vitro and in vivo experiments demonstrated the targeted demethylation system upregulated ZNF334 expression and inhibited CRC growth. Collectively, targeted DNA demethylation of the ZNF334 promoter sheds light on the precise treatment of CRC.
In comparison to phased array (PA) radar that just transmits a beampattern with angle-dependent, frequency diverse array (FDA) radar with adding a feature of distance dimension performs well in main-beam deceptive jamming suppression domain. However, in practical conditions, estimating an inaccuracy of the covariance matrix(CM) has a significant negative impact on algorithm performance, also as a mismatch of target SV has. Hence, a robust adaptive beamforming technique comes up in this article that selects the principal eigenvector to get accurate signal steering vectors (SV), further gets the reconstruction interference-plus-noise CM (IPNCM). According to experiments, the proposed algorithm keeps a robust and good performance under non-ideal circumstances.
Microwave hyperthermia using the phased array applicator is a non-invasive treatment modality for breast cancer. Hyperthermia treatment planning (HTP) is critical to accurately treating breast cancer and avoiding damage to the patient’s healthy tissue. A global optimization algorithm, differential evolution (DE) algorithm, has been applied to optimize HTP for breast cancer and its ability to improve the treatment effect was proved by electromagnetic (EM) and thermal simulation results. DE algorithm is compared to time reversal (TR) technology, particle swarm optimization (PSO) algorithm, and genetic algorithm (GA) in HTP for breast cancer in terms of convergence rate and treatment results, such as treatment indicators and temperature parameters. The current approaches in breast cancer microwave hyperthermia still have the problem of hotspots in healthy tissue. DE enhances focused microwave energy absorption into the tumor and reduces the relative energy of healthy tissue during hyperthermia treatment. By comparing the treatment results of each objective function used in DE, the DE algorithm with hotspot to target quotient (HTQ) as the objective function has outstanding performance in HTP for breast cancer, which can increase the focused microwave energy of the tumor and decrease the damage to healthy tissue.
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