Preparation of Antioxidant and Antibacterial Chitosan Film from Periplaneta americana

Among different insects, the American cockroach (Periplaneta americana) has been bred in industrial scale successfully as a potential resource of protein, lipid, and antibacterial peptide. However, the application of its chitosan has not been studied widely, which has hindered the sufficient utilization of P. americana. In this paper, the chitosan from P. americana was separated, characterized, and processed into film (PaCSF) to examine its potential of being applied in food packaging. As the results of different characterizations showed, PaCSF was similar to shrimp chitosan film (SCSF). However, concerning the performances relating to food packaging, the two chitosan films were different. PaCSF contained more water (42.82%) than SCSF did, resulting in its larger thickness (0.08 mm). PaCSF could resist UV light more effectively than SCSF did. Concerning antioxidant activity, the DPPH radical scavenging ability of PaCSF increased linearly with time passing, reaching 72.46% after 8 h, which was better than that of SCSF. The antibacterial activity assay exhibited that PaCSF resisted the growth of Serratia marcescens and Escherichia coli more effectively than SCSF did. The results implied that P. americana chitosan could be a potential raw material for food packaging, providing a new way to develop P. americana

Chimeric antigen receptors for adoptive T cell therapy in acute myeloid leukemia

Abstract Currently, conventional therapies for acute myeloid leukemia (AML) have high failure and relapse rates. Thus, developing new strategies is crucial for improving the treatment of AML. With the clinical success of anti-CD19 chimeric antigen receptor (CAR) T cell therapies against B-lineage malignancies, many studies have attempted to translate the success of CAR T cell therapy to other malignancies, including AML. This review summarizes the current advances in CAR T cell therapy against AML, including preclinical studies and clinical trials, and discusses the potential AML-associated surface markers that could be used for further CAR technology. Finally, we describe strategies that might address the current issues of employing CAR T cell therapy in AML

An intravenous clarithromycin lipid emulsion with a high drug loading, H-bonding and a hydrogen-bonded ion pair complex exhibiting excellent antibacterial activity

The aim of this study was to develop an intravenous clarithromycin lipid emulsion (CLE) with good stability and excellent antibacterial activity. The CLE was prepared by the thin-film dispersed homogenization method. The interaction between clarithromycin (CLA) and cholesteryl hemisuccinate (CHEMS) was confirmed by DSC, FT-IR and 1H NMR analysis. The interfacial drug loading, thermal sterilization, freeze–thaw stability, and in vitro and in vivo antibacterial activity were investigated systematically. DSC, FT-IR and 1H NMR spectra showed that CHEMS (CLA: CHEMS, M ratio 1:2) could interact with CLA through H-bonding and a hydrogen-bonded ion pair. The CHEMS was found necessary to maintain the stability of CLE. Ultracentrifugation showed that almost 88% CLA could be loaded into the interfacial layer. The optimized CLE formulation could withstand autoclaving at 121 °C for 10 min and remain stable after three freeze–thaw cycles. The in vitro susceptibility test revealed that the CLA–CHEMS ion-pair and CLE have similar activity to the parent drug against many different bacterial strains. The in vivo antibacterial activity showed that the ED50 of intravenous CLE was markedly lower than that of CLA solution administrated orally. CLE exhibited pronounced antibacterial activity and might be a candidate for a new nanocarrier for CLA with potential advantages over the current commercial formulation

Clarithromycin ion pair in a liposomal membrane to improve its stability and reduce its irritation caused by intravenous administration

<p><b><i>Objective</i>:</b> The aim of this study was to improve the drug loading (DL) and stability of clarithromycin (CLA)-loaded liposomes, and reduce the irritation caused by intravenous administration of CLA.</p> <p><b><i>Methods</i>:</b> A CLA–cholesteryl hemisuccinate (CHEMS) ion pair (CIP) was prepared by the solvent evaporation method and confirmed by fourier transform infrared spectroscopy, ¹H-nuclear magnetic resonance, differential scanning calorimetry and X-ray powder diffraction. Subsequently, CIP liposomes (CIP-Lip) were prepared by the thin-film dispersion method and evaluated in terms of their size, zeta-potential, <i>in vitro</i> release, stability, <i>in vitro</i> antimicrobial activity and irritation.</p> <p><b><i>Results</i>:</b> The CIP-Lip exhibited a homogeneous round shape, and their size, <i>ζ</i>-potential, encapsulation efficiency (EE) and DL were 71.89 ± 2.6 nm, −9.91 ± 0.82 mV, 95.1 ± 1.5% and 7.8 ± 0.3%, respectively. The physical appearance and drug content of CIP-Lip over a three-month storage remained almost unchanged. The release of CLA in CIP-Lip was pH-dependent, with a more rapid release at pH 6.0 than at pH 7.4. Although the <i>in vitro</i> antimicrobial activity of CIP-Lip was comparable with free CLA, the irritation produced by CIP-Lip was significantly reduced compared with CLA solution.</p> <p><b><i>Conclusions</i>:</b> These findings suggest that CIP-Lip is a promising intravenous drug delivery system, especially on account of its high DL and reduced irritation.</p