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Chemotherapeutic regimens containing sorafenib are widely used in salvage treatment for patients with relapsed and refractory acute leukemia, especially those with FLT3-ITD mutations. However, the therapeutic effects in individuals are heterogeneous, and the effective maintenance period is relatively short. Our clinical analysis showed patients with high c-kit (CD117) expression in leukemia cells generally had a better response to sorafenib, but the reason for this finding was not clear. c-kit (CD117) is a receptor tyrosine kinase, and its signal inactivation and hydrolytic metabolism are regulated by the CBL protein, a Ring finger E3 ubiquitin ligase, encoded by the c-CBL gene. And we also found that the c-CBL gene expression in refractory and relapsed patients was significantly lower than that in healthy hematopoietic stem cell donors. Therefore, we assumed that there is a relationship among c-CBL gene function, high expression of c-kit (CD117) and a better clinical response to sorafenib. To confirm this hypothesis, we packaged interfering lentiviruses and overexpressed adenoviruses targeting the c-CBL gene respectively, and infected leukemia cell lines with these viruses to regulate the expression of the c-CBL gene, and observed the subsequent changes of these cells in various biological behaviors. Our results showed when the c-CBL gene was silenced, the cells proliferation was accelerated, drug sensitivity to cytarabine or sorafenib was decreased, and apoptosis ratio was decreased. And all these phenomena were reversed when the gene was overexpressed, which confirmed the expression of c-CBL gene was related to drug resistance in leukemia cells. At last, we explored the possible molecular mechanisms underlying these phenomena. [ABSTRACT FROM AUTHOR]

A broadband diplexer-integrated double-pole single-throw (DPST) switch is proposed to realize frequency division duplexing (FDD) and time division duplexing (TDD). It consists of a lowpass filter (LPF) and a bandpass filter (BPF). The series LC resonators are used in both channels to create transmission zeros (TZs) in the stopband to ensure high selectivity. The diplexer is realized by inter-digital capacitors and microstrip section inductors, which can achieve low cost and compact size. Besides, this diplexer does not require a T-junction, achieving a compact size. For demonstration, a diplexer operating in DC-1.78/3.29–4.42 GHz has been designed, fabricated, and measured. The diplexer has four operating modes. And it has a compact size of 24.67 mm × 21.4 mm. The measured results show that the diplexer exhibits broadband, low insertion losses, high isolation, and high selectivity. [ABSTRACT FROM AUTHOR]

In the article, a design method of tunable bandpass filter based on epsilon-near-zero (ENZ) metamaterials using liquid crystals (LCs) is proposed. Thanks to the strong and directionally consistent electric field distribution caused by energy tunnelling effect of ENZ metamaterials, the ENZ unit cell with filled LC in the narrow tunnel can theoretically achieve the bandpass filtering characteristic with a large tuning rate. On this basis, a third-order LC-based tunable bandpass filter is constructed by three series unit structures, which achieves obviously tunable bandpass filtering characteristic with different external biased voltages. Finally, one prototype is designed, fabricated and measured, respectively. The measurement results show that the proposed bandpass filter based on ENZ materials with LCs can achieve effective tuning of the operating frequency with different external biased voltages, which verifies the effectiveness of the proposed design method. In addition, the impact of shape variation of the proposed ENZ-based tunable filter on electromagnetic characteristics is also further discussed and analysed in experiments, which is of great significance for achieving RF miniaturisation and high integration. [ABSTRACT FROM AUTHOR]

Controlling objects with body language is an extremely interesting ability for human beings. Recognizing different gestures is an effective way to collect valuable information, which is used to switch the radiation characteristic of beam scanning antennas. However, most existing beam scanning antennas are wire-connected and manually controlled by users. Thereby, a novel framework of gesture-controlled antennas is proposed in this paper. Rather than DC voltages supplied by powers or AC voltages supplied by signal generators, the beam scanning antenna can be effectively controlled by different gesture commands collected in real time from the user. On this basis, considering the advantages of the low cost and wide frequency band of liquid crystal (LC) materials, a LC-based fixed-frequency beam scanning leaky wave antenna (LWA) with gesture-controlled systems is demonstrated as one example. Different gestures can be recognised as controlled information to supply corresponding output signals by field programmable gate arrays (FPGAs) for the LC-based LWA. Based on the proposed framework, a verification system is tested, which demonstrates that the radiation characteristic can be effectively controlled by the user's gesture. This work supplies a novel way for intelligent beam scanning antennas with potential applications in the internet of things (IoT), satellite and 5 G/6 G communications. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 41-year-old Chinese male patient who experienced splenomegaly and fatigue while diagnosed with chronic myeloid leukemia (CML). It mentions the condition of the patient while he was treated from January 2007 to February 2010 including the progressive blast crisis and recurrent pleural effusion. It also warns the possibility that low-concentration of dasatinib will fail to eradicate all leukemia cells in the central nervous system due to its insufficiency.