Nanoemulsion: A novel delivery approach for thermosensitive IgG on inhibiting milk fat oxidation.

IgG, a biologically active substance in bovine colostrum, is easily inactivated during heat treatment and edible process to lose its biological activity. Nanoemulsion can effectively protect IgG to maintain its biological activity from injurious treatment. In this study, a food-grade nanoemulsion system was developed to protect IgG from heat and acid damage. It can be found that the residual rate of nanoemulsion-protected IgG reaches 87.1 % after 10 min at 72 °C. After 5 min at 82 °C, the residual rate of IgG in nanoemulsion was 18.7 % higher than that in PBS. In the simulated gastric fluid at pH 2.0, the residual rate of IgG in the nanoemulsion reacted for 4 h was 21.5 % higher than that in PBS. It indicated that nanoemulsion system can improve the heat and acid resistance of IgG compared with others, which is attributed to the lowest water activity of nanoemulsion. The contents of hydroperoxide and malondialdehyde in the milk after storage for 72 h with nanoemulsion-protected IgG were 0.12 meq/kg and 0.04 mg/kg, respectively, less than that of PBS-protected IgG. IgG is protected by nanoemulsion can effectively protect its activity during processing, which provides a theoretical basis for its direct application in liquid milk.

MA104 Cell line presents characteristics suitable for enterovirus A71 isolation and proliferation.

Enterovirus A71 (EV-A71), one of the most important causative agents of hand, foot and mouth disease (HFMD) in children, can lead to severe clinical outcomes, even death. However, the infection spectrum of EV-A71 in different cell lines remains unknown. Therefore, in this study, the biological characteristics of EV-A71 Subgroup C4 in different cell lines were investigated. To this end, the infectivity of EV-A71Jinan1002 isolated from children with severe HFMD was assessed in 18 different host cell lines. It was found that the MA104 cell line displayed biological characteristics suitable for EV-A71 Subgroup C4 strain isolation and proliferation; indeed, it was found that a broad spectrum of cell lines can be infected by EV-A71Jinan1002. Among the screened cells, four cell lines (HEK293, RD, MA104 and Marc145) produced high 50% tissue culture infective dose (TCID50 ) values calculated in viral proliferations (ranged from 10(7.6) to 10(7.8) ); the TCID50 being negatively associated with the time to appearance of CPE. Proliferation curves demonstrated that EV-A71Jinan1002 amplifies more efficiently in MA104, Hep-2 and RD cells. Remarkably, the virus isolation rate was much higher in MA104 cells than in RD cells. Thus this study, to our knowledge, is for the first to explore the infection spectrum of EV-A71 subgroup C4 in such a large number of different cell lines. Our data provide useful reference data for facilitating further study of EV-A71.

[Study on BALB/c mice with EV71 infection by diverse inoculation routes].

OBJECTIVE: To study the characteristics of EV71 JN200804 strain infection in one-day old BALBI c mjce and to establish a animal model of EV71 infection , and to provide information and technical support for the evaluation of the EV71 vaccine and antiviral medicine. METHODS: One-day old BALBic mice were infected with EV71 JN200804 strain through oral( PO) ,intracranial(IC) ,intraperitoneal (IP), intramuscular (IM) routes, respectively. All mice were sacrificed at paralysis of hind limbs and collected organs for viral isolation, RT -PCR and pathological examination, and the electrophysiology were detected before sacrifice. RESULTS: All mice infected through IC, IP and IM routes were paralyzed in hind limbs at 4-5 days and died at 7 days about, the hypokinesia and lethargy of mice were observed through PO routes. The viruses could be isolated and detected in the muscle from mice infected through IC, IP and IM routes and in the spinal cord through IC routes by viral isolation and RT-PCR. The neurogenic and myogenic disorders were detected by electromyography. Histopathologically, the varied pathologic changes were observed in the mouse cerebellum , spinal cord , muscle , heart, lung, liver and kidney. CONCLUSION: EV71 JN200804 strain can infect one-day old BALBI c mice and induce paralysis of hind limbs, its animal infection model may apply to study of EV71 infection pathogenesis and antiviral medicine, and evaluation of the EV71 vaccine.

A large perturbation on geometry structures, excited state properties, charge-injection and -transporting abilities of Ir(III) complexes by different substituents on ligands: a DFT/TDDFT study.

The molecular geometries, electronic structures, photophysical properties, charge-injection and -transporting abilities of a series of Ir(III) complexes with different carrier-transporting substituents, such as carbazole, oxadiazole and dimesitylboryl groups, are investigated theoretically using density functional theory (DFT) and time-dependent DFT (TDDFT) calculations to understand the influence of these substituents on the optical and electronic properties of Ir(III) complexes and to explore how to improve the optoelectronic properties of the complexes. It is found that the introduction of substituents can stabilize both HOMOs and LUMOs and induce variations in the energy gap between HOMO and LUMO. The introduction of hole-transporting carbazole substituent induces the blue-shift of absorption spectrum and improves the hole-injection and -transporting performances of complex. The introduction of electron-transporting oxadiazole substituent and electron-accepting dimesitylboryl substituent induces the red-shift in absorption spectra of complexes, improves their charge transfer abilities and leads to the better balance between the hole- and electron-transporting abilities. Through Lewis acid/base interactions between B atom and F(-), the electronic properties of 4 show dramatic changes in the presence of F(-) and thus 4 can also be used as selective phosphorescent F(-) probe.

[Dimo-thylidioctyl ammonium bromide-BCG polysaccharide nucleic acid adjuvant enhanced the immunogenicity of a Mycobacterium tuberculosis subunit vaccine].

OBJECTIVE: To investigate the activity of a novel adjuvant consisting of dimethyldioctyldecyl ammonium bromide (DDA) and BCG polysaccharide nucleic acid (BCG-PSN). METHODS: BCG-PSN was extracted by hot-phenol method, and combined with DDA and Mycobacterium tuberculosis fusion antigen AMM (Ag85B-MPT64(190-198)-Mtb8.4) to formulate the Mycobacterium tuberculosis subunit vaccine. Mice were immunized subcutaneously with a 2-week interval between the immunizations (0.2 ml/dose), and humoral and cell-mediated immunity were detected by ELISA and ELISPOT respectively. RESULTS: With the stimulation of Ag85B in vitro, the number of antigen specific IFN-gamma producing spleen lymphocytes were 222 +/- 79, 259 +/- 85, 230 +/- 64 per million respectively in the mice immunized with AMM + DDA + BCG-PSN, AMM + DDA, and BCG. Spleen lymphocytes in these 3 groups produced higher levels of IFN-gamma compared to the groups with the adjuvant of IFA or BCG-PSN alone or without adjuvant upon stimulation with Ag85B (t = 2.923-7.118, P < 0.05). Furthermore, the adjuvant consisting of DDA and BCG-PSN increased the ratio of Ig(2a)/IgG1 than DDA alone (0.125 vs. 0.025). Combined with AMM, the adjuvant DDA and the one consisting of DDA and BCG-PSN induced higher level of immunity than incomplete Freund's adjuvant (IFA), NaCl, and BCG-PSN alone. CONCLUSION: Mycobacterium tuberculosis subunit vaccine AMM + DDA + BCG-PSN induced a strong Th1-type immune response, and DDA + BCG-PSN, especially DDA promoted the immune response of the M. tuberculosis subunit vaccine in mice.