Radionuclides can be hazardous by absorbed through the skin, respiratory and digestive tracts. Chelating agents and adsorbents already could effectively remove them, however traditional chelators have side effects such as nephrotoxicity, teratogenicity, and embryotoxicity. As a new type of nuclide adsorbent, polysaccharide has the advantages of safety, biocompatibility, and high clearance rate. In this paper, the main types and perniciousness of radionuclides, and the latest research of polysaccharides in radionuclide removal were summarized. The application of polysaccharide as an effective adsorption molecule for radio nuclides in nuclear wars, nuclear accidents and other sudden nuclear events is promising.

Metastatic lung cancer continues to cause a high number of deaths due to high malignancy and poor prognosis, and the efficacy of typical chemotherapy or immunotherapy is less than ideal due to the low pulmonary accumulation and targeting of therapeutics. Here, a submicron-sized biomimetic liposome was formulated for the lung-targeted co-delivery of bacterial superantigen and paclitaxel. Recombinant staphylococcal enterotoxin C2 (rSEC2), a bacterial superantigen, was expressed with the Escherichia coli system and showed potent immunostimulatory activities to mediate tumor cell death. The submicron-sized (∼800 nm) biomimetic liposomes, namely 4T1 cell membrane-hybrid rSEC2 paclitaxel liposomes (TSPLs), exhibited high lung-accumulation efficiency and tumor homologous effect due to the suitable particle size and membrane hybridization of cancer cell membranes with phospholipids. Intravenous TSPLs remarkably inhibited metastatic lung cancer with limited systemic immune responses. TSPLs reversed the immunosuppressive state and increased the proportion of local CD4⁺ and CD8⁺ T cells in the lung; moreover, paclitaxel increased tumor cell apoptosis and reduced tumor burden. In summary, the high lung cancer targeting was achieved by particle size control and cell membrane hybridization, and the highly efficient anticancer effect was achieved by the co-delivery of superantigens and chemotherapeutic drugs.

Wound infection is becoming a considerable healthcare crisis due to the abuse of antibiotics and the substantial production of multidrug-resistant bacteria. Seawater immersion wounds usually become a mortal trouble because of the infection of Vibrio vulnificus. Bdellovibrio bacteriovorus, one kind of natural predatory bacteria, is recognized as a promising biological therapy against intractable bacteria. Here, we prepared a B. bacteriovorus-loaded polyvinyl alcohol/alginate hydrogel for the topical treatment of the seawater immersion wounds infected by V. vulnificus. The B. bacteriovorus-loaded hydrogel (BG) owned highly microporous structures with the mean pore size of 90 μm, improving the rapid release of B. bacteriovorus from BG when contacting the aqueous surroundings. BG showed high biosafety with no L929 cell toxicity or hemolysis. More importantly, BG exhibited excellent in vitro anti-V. vulnificus effect. The highly effective infected wound treatment effect of BG was evaluated on mouse models, revealing significant reduction of local V. vulnificus, accelerated wound contraction, and alleviated inflammation. Besides the high bacterial inhibition of BG, BG remarkably reduced inflammatory response, promoted collagen deposition, neovascularization and re-epithelization, contributing to wound healing. BG is a promising topical biological formulation against infected wounds.

Nano-drug delivery strategies have been highlighted in cancer treatment, and much effort has been made in the optimization of bioavailability, biocompatibility, pharmacokinetics profiles, and in vivo distributions of anticancer nano-drug delivery systems. However, problems still exist in the delicate balance between improved anticancer efficacy and reduced toxicity to normal tissues, and opportunities arise along with the development of smart stimuli-responsive delivery strategies. By on-demand responsiveness towards exogenous or endogenous stimulus, these smart delivery systems hold promise for advanced tumor-specificity as well as controllable release behavior in a spatial-temporal manner. Meanwhile, the blossom of nanotechnology, material sciences, and biomedical sciences has shed light on the diverse modern drug delivery systems with smart characteristics, versatile functions, and modification possibilities. This review summarizes the current progress in various strategies for smart drug delivery systems against malignancies and introduces the representative endogenous and exogenous stimuli-responsive smart delivery systems. It may provide references for researchers in the fields of drug delivery, biomaterials, and nanotechnology.

Although high-efficiency targeted delivery is investigated for years, the efficiency of tumor targeting seems still a hard core to smash. To overcome this problem, we design a three-step delivery strategy based on streptavidin-biotin interaction with the help of c(RGDfK), magnetic fields and lasers. The ultrasmall superparamagnetic iron oxide nanoparticles (USIONPs) modified with c(RGDfK) and biotin are delivered at step 1, followed by streptavidin and the doxorubicin (Dox) loaded nanosystems conjugated with biotin at steps 2 and 3, respectively. The delivery systems were proved to be efficient on A549 cells. The co-localization of signal for each step revealed the targeting mechanism. The external magnetic field could further amplify the endocytosis of USPIONs based on c(RGDfK), and magnify the uptake distinctions among different test groups. Based on photoacoustic imaging, laser-heating treatment could enhance the permeability of tumor venous blood vessels and change the insufficient blood flow in cancer. Then, it was noticed that only three-step delivery with laser-heating and magnetic fields realized the highest tumor distribution of nanosystem. Finally, the magnetism/laser-auxiliary cascaded delivery exhibited the best antitumor efficacy. Generally, this study demonstrated the necessity of combining physical, biological and chemical means of targeting.

Background: The etiology and pathogenesis of irritable bowel syndrome (IBS) are not yet clear, and is lack of effective means for its prevention, diagnosis and treatment in clinic. In recent years, more and more studies showed that intestinal local mucosal immune dysfunction plays an important role in the pathogenesis of IBS. Aims: To investigate the role of intestinal dendritic cells (DC) in the imbalance of colonic mucosal Th1/Th2 immune response pathway in IBS with diarrhea (IBS-D) rats and its effect on visceral hypersensitivity. Methods: Forty-five adult SD rats were randomly divided into blank control group, NS control group and model group, and each group consisted of 15 rats. Visceral hypersensitive model was established by acetic acid enema combined with restraint stress. Abdominal withdrawal reflex (AWR) test and fecal characteristics were used to evaluate the visceral sensitivity. Flow cytometry separation technique was used to isolate DC from mesenteric lymph nodes and CD4

Isovalerylspiramycin (ISP)Ⅰ, as a major component of bitespiramycin (BT), exhibits similar antimicrobial activities with BT and has advantages in quality control and dosage forms. It has been under preclinical studies. The existing ISPⅠ producing strain, undergoing three genetic modifications, carries two resistant gene markers. Thus, it is hard for further genetic manipulation. It is a time-consuming and unsuccessful work to construct a new ISPⅠ strain without resistant gene marker by means of the classical homologous recombination in our preliminary experiments. Fortunately, construction of the markerless ISPⅠ strain, in which the bsm4 (responsible for acylation at 3 of spiramycin) gene was replaced by the Isovaleryltansferase gene (ist) under control of the constitutive promoter ermEp*, was efficiently achieved by using the CRISPR-Cas9 gene editing system. The mutant of bsm4 deletion can only produce SPⅠ. Isovaleryltransferase coded by ist catalyzes the isovalerylation of the SPⅠat C-4" hydroxyl group to produce ISPⅠ. As anticipated, ISPⅠ was the sole ISP component of the resultant strain (ΔEI) when detected by HPLC and mass spectrometry. The ΔEI mutant is suitable for further genetic engineering to obtain improved strains by reusing CRISPR-Cas9 system.
CRISPR-Cas Systems ; Gene Editing ; Genetic Engineering ; Homologous Recombination

Drug delivery systems (DDS) are defined as methods by which drugs are delivered to desired tissues, organs, cells and subcellular organs for drug release and absorption through a variety of drug carriers. Its usual purpose to improve the pharmacological activities of therapeutic drugs and to overcome problems such as limited solubility, drug aggregation, low bioavailability, poor biodistribution, lack of selectivity, or to reduce the side effects of therapeutic drugs. During 2015-2018, significant progress in the research on drug delivery systems has been achieved along with advances in related fields, such as pharmaceutical sciences, material sciences and biomedical sciences. This review provides a concise overview of current progress in this research area through its focus on the delivery strategies, construction techniques and specific examples. It is a valuable reference for pharmaceutical scientists who want to learn more about the design of drug delivery systems.

Objective: To explore the characteristics underlying Th1/Th2/Th17 expression level after entecavir (ETV) discontinuation of chronic hepatitis B (CHB) patients who were HBeAg-positive and define the role of Th1/Th2/Th17 in maintaining virological response after ETV discontinuation. Methods: We selected 112 HBeAg positive CHB patients who met the withdrawal criteria according to the guideline of prevention and treatment of chronic hepatitis B (2010 version), and we also separated them into virology sustained response (SVR) group and virological relapse (VR) group according to the recurrence in 52 weeks. We detected serum level of Th1/Th2/h17 related cytokines during 0, 12, 24 and 52 weeks follow-up to further analyze their dynamic changes and expression differences. Results: The results of the study reveals that serum levels of IFN-γ in the group of SVR were at a higher level compared with VR group during follow-up (all P<0.05). While, the serum level of IL-10 decreased in SVR group and was lower than the paired IL-10 level in VR group with significance during follow-up. In VR group, the serum level of IFN-γ decreased during the first 24 weeks after ETV withdrawal, and after then, the level rose. The serum levels of IFN-γ (Th1) in SVR patients were significantly higher than those in VR patients in the different follow-up time points after ETV discontinuation (all P<0.05). And the serum levels of IL-10 (Th2) in SVR patients were significantly lower than that in VR patients (all P<0.05). The comparison of serum levels of IL-17A (Th17) between the two groups had no significant difference (all P>0.005). Conclusions The serum level of IFN-γ in SVR group maintained a high level is conducive to maintaining virological response after ETV withdrawal and high level of IL-10 may be related to virologic relapse.

Lung cancer is the leading cause of cancer-related deaths. Traditional chemotherapy causes serious toxicity due to the wide bodily distribution of these drugs. Curcumin is a potential anticancer agent but its low water solubility, poor bioavailability and rapid metabolism significantly limits clinical applications. Here we developed a liposomal curcumin dry powder inhaler (LCD) for inhalation treatment of primary lung cancer. LCDs were obtained from curcumin liposomes after freeze-drying. The LCDs had a mass mean aerodynamic diameter of 5.81 μm and a fine particle fraction of 46.71%, suitable for pulmonary delivery. The uptake of curcumin liposomes by human lung cancer A549 cells was markedly greater and faster than that of free curcumin. The high cytotoxicity on A549 cells and the low cytotoxicity of curcumin liposomes on normal human bronchial BEAS-2B epithelial cells yielded a high selection index partly due to increased cell apoptosis. Curcumin powders, LCDs and gemcitabine were directly sprayed into the lungs of rats with lung cancer through the trachea. LCDs showed higher anticancer effects than the other two medications with regard to pathology and the expression of many cancer-related markers including VEGF, malondialdehyde, TNF-, caspase-3 and BCL-2. LCDs are a promising medication for inhalation treatment of lung cancer with high therapeutic efficiency.