Tissue-derived extracellular vesicles: Research progress from isolation to application

Extracellular vesicles (EVs) are the structures that all cells release into the environment. They are separated by a lipid bilayer and contain the cellular components that release them. To date, most studies have been performed on EVs derived from cell supernatants or different body fluids, while the number of studies on EV isolation directly from tissues is still limited. Studies of EV isolation directly from tissues may provide us with better information. This review summarizes the role of EV in the extracellular matrix, the protocol for isolation of EV in the tissue interstitium, and the application of the protocol in different tissues.

[Study on time-toxicity relationship and mechanism of Gardeniae Fructus extract on hepatoxicity in rats based on proteomics]

To study the time-toxicity relationship and mechanism of Gardeniae Fructus extract on the hepatoxicity in rats. Rats were randomly divided into C group(0 day), D5 group(5 days), D12 group(12 days), D19 group(19 days), and D26 group(7 days recovery after 19 days of administration). The rats in normal group received normal saline through intragastric administration, and the rats in other groups received 10 g·kg~(-1 )Gardeniae Fructus extract through intragastric administration. After the final administration, the livers were collected. Hematoxylin-eosin staining was used to observe the histopathological changes in the liver tissue. Total liver proteins were extracted for proteomic analysis, detected by the Nano-ESI liquid-mass spectrometry system and identified by Protein Disco-very software. SIEVE software was used for relative quantitative and qualitative analysis of proteins. The protein-protein interaction network was constructed based on STRING. Cytoscape software was used for cluster analysis of differential proteins. Kyoto encyclopedia of genes and genomes(KEGG) database was used to perform enrichment signal pathway analysis. Pearson correlation analysis was performed for the screened differential protein expression and liver pathology degree score. The results showed that the severity of liver injury in D5, D12 and D19 groups was significantly higher than that in group C. The degree of liver damage in D5 group was slightly higher than that in D12 and D19 groups, with no significant difference between group D26 and group C. Totally 147 key differential proteins have been screened out by proteomics and mainly formed 6 clusters, involving in drug metabolism pathways, retinol metabolism pathways, proteasomes, amino acid biosynthesis pathways, and glycolysis/gluconeogenesis pathways. The results of Pearson correlation analysis indicated that differential protein expressions had a certain temporal relationship with the change of liver pathological degree. The above results indicated that the severity of liver damage caused by Gardeniae Fructus extract did not increase with time and would recover after drug with drawal. The above pathways may be related to the mechanism of liver injury induced by Gardeniae Fructus extract.

Cryptococcosis manifesting as isolated biliary infection: Case report and brief review of literature

BACKGROUND

Biliary cryptococci infection is rare, which is frequently diagnosed by exploratory laparotomy, preoperative diagnosis is difficult.

CASE PRESENTATION

A 14-year-old girl presented with intermittent jaundice for 6 years. She had no pruritus, anorexia, nausea or vomiting, fever, abdominal pain, or clay stools. Laboratory tests showed obstructive jaundice, eosinophilia, and increased IgE levels. The patient was ultimately diagnosed as Cryptococcal infection by bone marrow culture. The patient responded to antifungal therapy.

CONCLUSION

Unnecessary surgical intervention was avoided by an early and accurate diagnosis. Cryptococcosis infection of bile duct should be highly suspected, when the children with obstructive jaundice have eosinophilia and increased IgE levels.

Molecular organization in the twist-bend nematic phase by resonant X-ray scattering at the Se K-edge and by SAXS, WAXS and GIXRD

Using a magnetically aligned liquid crystal mixture containing a novel Se-labelled dimer and the difluoroterphenyl dimer DTC5C7, the twist-bend nematic phase (N_tb) was studied by the resonant scattering of hard X-rays and by conventional small and wide-angle X-ray scattering (SAXS, WAXS). Resonant diffraction spots indicated a helix with a 9-12 nm pitch in the N_tb phase and an unprecedentedly high helix orientation. This enabled deconvolution of global and local order parameters. These findings, combined with the simultaneously recorded resonant and non-resonant SAXS and WAXS data, allowed us to construct a locally layered molecular model of the N_tb phase, where the average twisted conformation of each molecule was idealised as a helical segment, matching the local heliconical director field. The dimers were found to be less bent in the N_tb phase than in their minimum energy conformation, and straightening further with increasing temperature. It is proposed that on further heating their low bend angle allows the transition to the normal nematic phase, where the molecules can freely move longitudinally, without the need to perform screw-like motion as in the N_tb phase. At the low-temperature end, the increasing molecular twist becomes unsustainable, leading to a transition to a smectic phase, where no twist is required.

Heavy metal accumulation and source analysis in greenhouse soils of Wuwei District, Gansu Province, China

Greenhouse soils and arable (wheat field) soil samples were collected to identify the effects of greenhouse cultivation on the accumulation of six heavy metals (Cd, Cu, Zn, Pb, Cr, and Ni) and to evaluate the likely sources responsible for heavy metal accumulation in the irrigated desert soils of Wuwei District, China. The results indicated that the mean concentrations of Cd, Cu, Zn, Pb, Cr, and Ni were 0.421, 33.85, 85.31, 20.76, 53.12, and 28.59 mg kg(-1), respectively. The concentrations of Cd, Cu, and Zn in greenhouse soils were 60, 23, and 14% higher than those in arable soils and 263, 40, and 25% higher than background concentrations of natural soils in the study area, respectively. These results indicated that Cd, Cu, and Zn accumulation occurred in the greenhouse soils, and Cd was the most problematically accumulated heavy metal, followed by Cu and Zn. There was a significant positive correlation between the concentrations of Cd, Cu, and Zn in greenhouse soils and the number of years under cultivation (P < 0.05). Greenhouse cultivation had little impact on the accumulation of Cr, Ni, or Pb. Correlation analysis and principal component analysis suggested that the accumulation of Cd, Cu, and Zn in greenhouse soils resulted mainly from fertilizer applications. Our results indicated that the excessive and long-term use of fertilizers and livestock manures with high heavy metal levels leads to the accumulation of heavy metals in soils. Therefore, rational fertilization programs and reductions in the concentrations of heavy metals in both fertilizers and manure must be recommended to maintain a safe concentration of heavy metals in greenhouse soils.

Arsenate reduction and methylation in the cells of Trichoderma asperellum SM-12F1, Penicillium janthinellum SM-12F4, and Fusarium oxysporum CZ-8F1 investigated with X-ray absorption near edge structure

Synchrotron radiation-based X-ray absorption near edge structure (XANES) was introduced to directly analysis chemical species of arsenic (As) in the cells of Trichoderma asperellum SM-12F1, Penicillium janthinellum SM-12F4, and Fusarium oxysporum CZ-8F1 capable of As accumulation and volatilisation. After exposure to As(V) of 500 mg L(-1) for 15 days, a total of 60.5% and 65.3% of the accumulated As in the cells of T. asperellum SM-12F1 and P. janthinellum SM-12F4, respectively, was As(III), followed by 31.3% and 32.4% DMA (dimethylarsinic acid), 8.3% and 2.3% MMA (monomethylarsonic acid), respectively. However, for F. oxysporum CZ-8F1, 54.5% of the accumulated As was As(III), followed by 37.8% MMA and 7.7% As(V). The reduction and methylation of As(V) formed As(III), MMA, and DMA as the primacy products, and the reduction of As(V) might be more easily processed than the methylation. These results will help to understanding the mechanisms of As detoxification and its future application in bioremediation.

Controllable preparation of ternary superparamagnetic nanoparticles dual-doped with Mn and Zn elements

Superparamagnetic iron oxide nanoparticles (SPIONs) with high saturation magnetization are successfully synthesized via thermal decomposition method by doping Mn and Zn elements simultaneously. The synthesis procedure was modified according to the thermal stabilities of the precursors, in order to ensure that the stoichiometry of the synthesized samples can be retained exactly from the starting ratios of the Fe/Mn/Zn in the initial precursors. As a result, the saturation magnetization of the dual-doped nanoparticles increased about 23% compared to that without the dopants. The superparamagnetic nanoparticles had narrow size distribution and the average diameter was about 8 nm. XRD and HRTEM analyses also indicated that the materials had a cubic spinel structure.

Facile synthesis of monodisperse superparamagnetic Fe3O4/PMMA composite nanospheres with high magnetization

Monodisperse superparamagnetic Fe(3)O(4)/polymethyl methacrylate (PMMA) composite nanospheres with high saturation magnetization were successfully prepared by a facile novel miniemulsion polymerization method. The ferrofluid, MMA monomer and surfactants were co-sonicated and emulsified to form stable miniemulsion for polymerization. The samples were characterized by DLS, TEM, FTIR, XRD, TGA and VSM. The diameter of the Fe(3)O(4)/PMMA composite nanospheres by DLS was close to 90 nm with corresponding polydispersity index (PDI) as small as 0.099, which indicated that the nanospheres have excellent homogeneity in aqueous medium. The TEM results implied that the Fe(3)O(4)/PMMA composite nanospheres had a perfect core-shell structure with about 3 nm thin PMMA shells, and the core was composed of many homogeneous and closely packed Fe(3)O(4) nanoparticles. VSM and TGA showed that the Fe(3)O(4)/PMMA composite nanospheres with at least 65% high magnetite content were superparamagnetic, and the saturation magnetization was as high as around 39 emu g(-1) (total mass), which was only decreased by 17% compared with the initial bare Fe(3)O(4) nanoparticles.

Effects of magnetic field on the antioxidant defense system of recirculation-cultured Chlorella vulgaris

Little is known about the influence of magnetic fields (MF) on growth of microalgae such as Chlorella vulgaris, which has been consumed as health food for various nutritional and pharmacological effects. This preliminary study investigated whether static MF can modulate the antioxidant system in C. vulgaris by exposing the cells to static MF generated by dual yoke electromagnets with magnetic flux density of 10-50 mT for 12 h. After exposure to 10-35 mT for 12 h, the activity of superoxide dismutases and peroxidase increased significantly compared to control cells. However, a remarkable increase of catalase activity occurred at 45 and 50 mT. The lipid peroxidation of algae cells determined by production of thiobarbituric acid-reactive substances was much increased when exposed to 35, 45, and 50 mT of MF. The scavenging ability of 2,2-diphenyl-1-picrylhydrazyl radical was decreased markedly while there was no variation of total carotenoids content in C. vulgaris cells. Assay of specific growth rate in 72 h cultivation after MF exposure was also conducted. In groups after exposure to 10-35 mT of MF, specific growth rate was significantly increased. These results suggest that 10-35 mT of static MF exposure could promote the growth of C. vulgaris and regulate its antioxidant defense system to protect cells efficiently, which could possibly enhance the growth of C. vulgaris in industrialized cultivation by MF.

Crystal-amorphous polymer interface studied by neutron and x-ray scattering on labeled binary ultralong alkanes

The recently discovered stable semicrystalline phase in binary ultralong alkanes is studied by small-angle neutron and x-ray scattering. Either the shorter or the longer alkane has (CD2)11CD3 ends. It is confirmed that chains are tilted in the crystal layer and found that ca. seven end carbons of the shorter alkane are amorphous. It is also established that the longer chains protrude from the crystal at both ends and that their end groups are preferentially located in the middle of the amorphous layer, suggesting gradual dissipation of orientational order of the chains exiting the crystal.

[Study on the relationship between PMI and the concentration of zincum and nickel in the vitreous humor of rabbit after death]

OBJECTIVE

To seek a exact method of estimating postmortem interval (PMI).

METHODS

This study detected the concentration of zincum(Zn) and nickel(Ni) in vitreous humor of rabbit at hour 96 after death and explored the relationship between their concentration and PMI using a method ICP-MS.

RESULTS

The concentration of Zn and Ni in vitreous humor of rabbit at hour 24 after death were related to PMI significantly; The formulae of the relationship between PMI and Zn concentrations is y = 0.1404x2 - 1.3351x + 3.8298 (within 24 h; R2 = 0.9202). The formula of the relationship between PMI and Ni concentrations is y = 0.0043x2 - 0.0596x + 0.2665(within 24 h; R2 = 0.9103).

CONCLUSION

The concentration of Zn and Ni in vitreous humor of rabbit may be a reference indicator to estimate early PMI.

Novel layered superstructures in mixed ultralong n-alkanes

Two new types of layered structures were found in binary mixtures of n-alkanes ranging from C122H246 to C294H590. At high temperatures a semicrystalline form is the stable phase, having a regular structure of alternating crystalline and amorphous layers. The two long-chain compounds are mixed in the crystalline layers and the amorphous layers consist of the surplus length of the longer chains. At lower temperatures a reversible transition occurs to a triple layer superlattice structure with a periodicity of up to 50 nm. These two new phases allow the existence of binary solid solutions of chains with a length ratio of up to 1.7 and a chain length difference of 100 CH2 groups.