Polymersomes from dual responsive block copolymers: drug encapsulation by heating and acid-triggered release.

A series of well-defined thermoresponsive diblock copolymers (PEO45-b-PtNEAn, n=22, 44, 63, 91, 172) were prepared by the atom transfer radical polymerization of trans-N-(2-ethoxy-1,3-dioxan-5-yl) acrylamide (tNEA) using a poly(ethylene oxide) (PEO45) macroinitiator. All copolymers are water-soluble at low temperature, but upon quickly heating to 37 °C, laser light scattering (LLS) and transmission electron microscopy (TEM) characterizations indicate that these copolymers self-assemble into aggregates with different morphologies depending on the chain length of PtNEA and the polymer concentration; the morphologies gradually evolved from spherical solid nanoparticles to a polymersome as the degree of polymerization ("n") of PtNEA block increased from 22 to 172, with the formation of clusters with rod-like structure at the intermediate PtNEA length. Both the spherical nanoparticle and the polymersome are stable at physiological pH but susceptible to the mildly acidic medium. Acid-triggered hydrolysis behaviors of the aggregates were investigated by LLS, Nile red fluorescence, TEM, and (1)H NMR spectroscopy. The results revealed that the spherical nanoparticles formed from PEO45-b-PtNEA44 dissociated faster than the polymersomes of PEO45-b-PtNEA172, and both aggregates showed an enhanced hydrolysis under acidic conditions. Both the spherical nanoparticle and polymersome are able to efficiently load the hydrophobic doxorubicin (DOX), and water-soluble fluorescein isothiocyanate-lysozyme (FITC-Lys) can be conveniently encapsulated into the polymersome without using any organic solvent. Moreover, FITC-Lys and DOX could be coloaded in the polymersome. The drugs loaded either in the polymersome or in the spherical nanoparticle could be released by acid triggering. Finally, the DOX-loaded assemblies display concentration-dependent cytotoxicity to HepG2 cells, while the copolymers themselves are nontoxic.

Bioavailability of quercetin in zein-based colloidal particles-stabilized Pickering emulsions investigated by the in vitro digestion coupled with Caco-2 cell monolayer model.

Protein-based Pickering emulsions have received considerable attention as nutraceutical vehicles. However, the oral bioavailability of nutraceuticals encapsulated in Pickering emulsions was not well established. In this work, a simulated gastrointestinal tract/Caco-2 cell culture model was applied to investigate the oral bioavailability of quercetin encapsulated in zein-based Pickering emulsions with quercetin in zein particles as the control. Pickering emulsions with shell (ZCP-QE) and core quercetin (ZCPE-Q) were constructed, and quercetin bioaccessibility, cell uptake and secretion, and the overall bioavailability were evaluated and compared. The overall oral bioavailability of quercetin was increased from 2.71% (bulk oil) to 38.18% (ZCPs-Q) and 18.97% (ZCPE-Q), particularly reached 41.22% for ZCP-QE. This work took new insights into the contributions of bioaccessibility and absorption (cell uptake plus secretion) to the overall oral bioavailability of quercetin. A schematic representation is proposed to relate the types of colloidal nanostructures in the digesta to the uptake, cell absorption, and overall oral bioavailability of quercetin. This study provided an attractive basis for identifying effective strategies to improve the oral bioavailability of hydrophobic nutraceuticals.

µ(4)-Sulfido-bis-{(µ-2-furyl-methane-thiol-ato)bis-[tricarbonyl-iron](Fe-Fe)}.

The title compound, [Fe(4)(C(5)H(5)OS)(2)S(CO)(12)], was prepared by the direct reaction of Fe(3)(CO)(12) and 2-furyl-methane-thiol in tetra-hydro-furan. Desulfurization took place readily to form an Fe(4)S(3) cluster. The mol-ecule consists of two similar [(µ-2-C(4)H(3)O-CH(2)S)Fe(2)(CO)(6)] moieties joined to a spiro-type four-coordinate µ(4)-S atom such that this bridging sulfur is tetra-hedrally coordinated to the four Fe atoms. In each diiron subcluster core, the 2-furyl-methane-thiol-ate ligand bridges the two Fe atoms.

Protein-Based Pickering High Internal Phase Emulsions as Nutraceutical Vehicles of and the Template for Advanced Materials: A Perspective Paper.

Pickering high internal phase emulsions (HIPEs) are normally highly concentrated emulsions stabilized by colloidal particles with a minimum internal phase volume fraction of 0.74. They have received considerable attention in many fields, including pharmaceuticals, tissue engineering, foods, and personal care products. The aim of this perspective is to update the current knowledge on the field of protein-based Pickering HIPEs, emphasizing those aspects that need to be explored and clarified. Research progress in constructing HIPEs by protein-type colloid particles and promising research trends in basic research and potential applications were highlighted. Promising studies in this field include (1) clarifying bioavailability and evolution of activity of active ingredients in Pickering HIPEs by oral administration, (2) constructing a Pickering interfacial catalysis platform using protein colloidal particles, and (3) expanding the emerging applications of Pickering HIPEs in fields, such as partially hydrogenated oil replacers, probiotic encapsulation, and the template for porous materials.

[Comparison of protein composition and activities of pilose antler processed by different methods].

To elucidate the influence of processing conditions on pilose antlers therapic effects, the protein composition and activities were compared on three kinds of pilose antler processed by lyophilization, freezing and traditional short-time heating, respectively. The concentration of the water soluble protein in freeze-dried pilose antler was 126.54 mg/g (Folin-Phenol assay), which was 13.1 times higher than that of heating processed antler. These proteins distributed widely in SDS-PAGE electrophoresis and the protein band between 50.0 kDa approximately 60.0 kDa achieved the highest concentration. The water extract of freeze-dried antler promoted the proliferation and IGF-I secretion of rat osteogenic-like cell UMR-106 by 245.25% ( MTT assay) and 66.36 ng/ml, which was respectively 2.2 times and 1.2 times of those of heating processed antler. The same candidate inhibited the growth of human hepatic carcinoma cell BEL-7402 by the highest rate of 47.64% , which was 1.4 times of heating processed antler. The activities of frozen fresh pilose antler were lower than those of its freeze-dried counterpart, but were much higher than those of heating processed antler. The results indicated that lyophilization help to remain the activity of pilose antlers proteins as much as possible and improve its efficacy.

Fabrication of Zein/Pectin Hybrid Particle-Stabilized Pickering High Internal Phase Emulsions with Robust and Ordered Interface Architecture.

Diets containing partially hydrogenated oils (PHOs) expose the human body to trans fatty acids, thus endangering cardiovascular health. Pickering high internal phase emulsions (HIPEs) is a promising alternative of PHOs. This work attempted to construct stable Pickering HIPEs by engineering interface architecture through manipulating the interfacial, self-assembly, and packing behavior of zein particles using the interaction between protein and pectin. Partially wettable zein/pectin hybrid particles (ZPHPs) with three-phase contact angles ranging from 84° to 87° were developed successfully. ZPHPs were irreversibly anchored at the oil-water interface, resulting in robust and ordered interfacial structure, evidenced by the combination of LB-SEM and CLSM. This situation helped to hold a percolating 3D oil droplet network, which facilitated the formation of Pickering HIPEs with viscoelasticity, excellent thixotropy (>91.0%), and storage stability. Curcumin in HIPEs was well protected from UV-induced degradation and endowed HIPEs with ideal oxidant stability. Fabricated Pickering HIPEs possess a charming application prospect in foods and the pharmaceutical industry.

Catalase-only nanoparticles prepared by shear alone: Characteristics, activity and stability evaluation.

Catalase is a promising therapeutic enzyme; however, it carries risks of inactivation and rapid degradation when it is used in practical bioprocess, such as delivery in vivo. To overcome the issue, we made catalase-only nanoparticles using shear stress alone at a moderate shear rate of 217s(-1) in a coaxial cylinder flow cell. Properties of nanoparticles, including particle size, polydispersity index and zeta potential, were characterized. The conformational changes of pre- and post-sheared catalase were determined using spectroscopy techniques. The results indicated that the conformational changes of catalase and reduction in α-helical content caused by shear alone were less significant than that by desolvation method. Catalase-only nanoparticles prepared by single shear retained over 90% of its initial activity when compared with the native catalase. Catalase nanoparticles lost only 20% of the activity when stored in phosphate buffer solution for 72h at 4°C, whereas native catalase lost 53% under the same condition. Especially, the activity of nanogranulated catalase was decreased only slightly in the simulated intestinal fluid containing α-chymotrypsin during 4h incubation at 37°C, implying that the catalase nanoparticle was more resistant to the degradation of proteases than native catalase molecules. Overall, catalase-only nanoparticles offered a great potential to stabilize enzymes for various pharmaceutical applications.

[Characteristics of Nitrogen and Phosphorus Losses in Longhong Ravine Basin of Westlake in Rainstorm Runoff].

In order to understand the non-point source pollution status in Longhong ravine basin of Westlake, the characteristics of nutrient losses in runoff was investigated during three rainstorms in one year. The results showed that long duration rainstorm event generally formed several runoff peaks, and the time of its lag behind the peaks of rain intensity was dependent on the distribution of heavy rainfall. The first flush was related to the antecedent rainfall, and the less rainfall in the earlier period, the more total phosphorus (TP) and ammonia (NH4+ -N) in runoff was washed off. During the recession of runoff, more subsurface runoff would result in a concentration peak of total nitrogen (TN) and nitrogen (NO3- -N) . The event mean concentration (EMC) of runoff nitrogen had a negative correlation with rainfall, rainfall duration, maximum rain intensity and average rain intensity except for antecedent rainfall, whereas the change in TP EMC showed the opposite trend. The transport fluxes of nutrients increased with an elevation in runoffs, and Pearson analysis showed that the transport fluxes of TN and NO3- -N had good correlations with runoff depth. The average transport fluxes of TP, TN, NH4+ -N and NO3- -N were 34.10, 1195.55, 1006.62 and 52.38 g x hm(-2), respectively, and NO3- -N was the main nitrogen form and accounted for 84% of TN.

[Purification and characterization of the proliferation of rat osteoblast-like cells UMR-106 from pilose antler].

OBJECTIVE: The activity of deer serum albumin on proliferation of rat osteogenic-like cells UMR-106 and the IGF-I secretion were investigated in order to elucidate pilose antler's bone-strengthening mechanism. METHOD: Deer serum albumin was isolated from freeze-dry pilose antler powder extract. The methods were Sephacryl S-200HR gel filtration, POROS 20QE ion-exchange and TSK G3000SW chromatographies. The effect of deer serum albumin on proliferatio of UMR-106 cells was assaied by MTT, and the secretion of IGF-I of UMR-106 cells was assaied by RIA. RESULT: Deer serum albumin, with the molecular weight of 56.3 kDa, significantly increased the proliferation rate of the osteoblast-like UMR-106 cell and IGF-I secretion. When concentration of deer serum albumin reached 0.149 microg x mL(-1), UMR-106 cell proliferation rate was 241.03% and IGF-I secretion was 66.89 ng x mL(-1). CONCLUSION: The concentration of deer serum albumin, from 14.9 ng x mL(-1) to 14.90 microg x mL(-1), significantly increased the proliferation rate of the osteoblast-like UMR-106 cell and IGF- I secretion.

[Enhancement of meniscal tearing damage repairing in the avascular zone using connective tissue growth factor (CTGF) in the rabbit model].

OBJECTIVE: To investigate effect of connective tissue growth factors (CTGF) on secretion of extracellular matrix synthesis of meniscal fibrochondrocytes, expression of vascular endothelial growth factors (VEGF), and angiogenesis during the repair of meniscal tearing damage. METHODS: Meniscal fibrochondrocytes were isolated from the inner--1/2 of rabbits' meniscus by collagenase enzymatic digestion, centrifugal separation, and treated with 100 ng/ml CTGF in vitro. Characterization of fibrochondrocytes was identified by flow cytometry analysising CD31, CD44, CD45 and CD105, and was further tested by type II collagen immunocytochemistry. Changes in gene expression of meniscal fibrochondrocytes were monitored by quantitative real-time polymerase chain reaction. In vitro, the sections of the 3 mm of the longitudinal teared in the middle of the rabbit's meniscus, and then the defects were dealed with simple suture, suture and implanting with PBS-fibrin glue, sutured and implanting with 1.5 microg CTGF respectively. Expression and distribution of type I and II collagen and VEGF, the tearing healing were observed by fluorescence-immunohistochemisty analysis on the 1st week, the 4th week and the 10th week. RESULTS: Quantitative RT-PCR assays showed that type I and type II collagen,and VEGF mRNA expression in the 100 ng/ml CTGF group had been remarkably enhanced than in the PBS group on the 14th day. Consistent with these effects in vitro, fluorescence-immunohistochemical analysis revealed that in the group implanted with CTGF-fibrin glue, type I collagen, type I collagen and capillaries completely filled the defect on the 10th week postoperatively. In contrast, only soft tissue repair occurred after the PBS-fibrin glue was implanted. CONCLUSION: CTGF can significantly promote extracellular matrix (I collagen, II collagen) of the meniscal avascular zone synthesis, and CTGF can greatly heighten the expression of VEGF activity at the same time in vitro, so that it can further enhance the repair of meniscal tearing damage in the avascular zone.

Multiple myeloma with rupture of ovarian plasmacytoma.

Multiple myeloma is a clonal proliferation of plasma cells with multiple osteolytic lesions. Extramedullary dissemination of multiple myeloma in ovary is relatively uncommon. A 54-year-old female patient, diagnosed as multiple myeloma three years ago, was admitted to the hospital for the complaints of intermittent abdominal pain for three days. The vaginal gynecological ultrasound showed celiac solid mass. The emergent laparotomy showed a significantly enlarged right cystic ovary and the pathological reviews showed ovarian plasmacytoma. The final diagnosis of this patient was ovarian extramedullary plasmacytoma rupture and bleeding.