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Customers can raise various aspects of concerns and anxieties during their participation in gamified social mobile marketing campaigns. To gain insights into how to address these anxieties, this research explores the impact of group-formation gamification mechanisms on users' emotional anxiety and their intentions to participate in such campaigns. A research model depicting group-formation gamification strategies, user anxieties and participation intentions in gamified social mobile marketing campaigns was proposed and examined through experiments involving 232 participants, which were triangulated by electroencephalogram (EEG) tests and follow-up interviews. The results of this study showed that compared with weak-tie group-formation mechanisms, strong-tie mechanisms can result in a lower level of user emotional anxiety, including reductions in user manipulation anxiety, user privacy anxiety and social image anxiety, which in turn led to higher user intentions to participate in the gamified social mobile marketing campaign. Moreover, it was found that user gender and disposable incomes had significant moderating effects on user anxiety during their interactions with the campaign. [ABSTRACT FROM AUTHOR]

Gonadotropin-releasing hormone (GnRH) agonists are peptides consisting of nine or ten amino acid residues. GnRH agonists have been applied in the therapy of sexual hormone disorders like prostate cancer, endometriosis, uterine myoma, central precious puberty, and in-vitro fertility. Treatment is achieved by continuous hormone intake and long-term agonists administration, which is usually associated with poor patient compliance. Because GnRH agonists that are administered with the parenteral route are broken down by peptidase, their half-life is short. As a result, developing sustained release for the drug delivery system is significant. Even though some drugs have been successfully delivered with long-acting release microspheres and approved by the Food and Drug Administration (FDA), some challenges remain. This review highlighted current approaches to encapsulate GnRH agonists into delivery systems and strategies encountered during the loading process. Moreover, the following sections provide strategies to improve the release profile, and animal and human studies were summarised. [ABSTRACT FROM AUTHOR]

Direct conjugation of bovine hemoglobin (Hb) and human serum albumin (HSA) with glutaraldehyde would result in a complex mixture of dimers Hb-Hb, Hb-HSA, HSA-HSA and other oligomers. To obtain a high yield of target Hb-HSA, modulation of the reaction environment was carried out. It was found that polyethylene glycol (PEG), a hydrophilic polymer, could improve the yield of Hb-HSA conjugate. The degree of improvement depended on the molecular weight and concentration of PEG. Under optimum condition of 9% (w/v) of PEG 4000, the reaction proceeded in a controlled mode with conversion yield of starting proteins to Hb-HSA increasing from 6% to 30%. The purity was about 88% of the total conjugates. Furthermore, the impurities were mainly tetrameric molecules of two Hb-HSA conjugates. The improvement could be attributed to the "micro-compartment" created by addition of polyethylene glycol, which brings HSA and Hb close together, thus increasing the chance of conjugation between the two molecules. [ABSTRACT FROM AUTHOR]

A facile, preparative low-pressure chromatographic process was developed for purification of paclitaxel from crude extract of Taxus spp. The process consisted of normal-phase and a reversed-phase chromatography without utilization of any liquid-liquid partition step. The normal phase chromatography was designed lo separate paclitaxel from a majority of unwanted compounds to obtain an initial purification. Silica gel and Al2O3, were compared as packing materials for this step. The result demonstrated that basic Al2O3 was better than silica gel to give a higher throughput. A further advantage of the Al2O3 was its ability of removing l0-deacetyl-7-epipaclitaxel. a compound difficult to be separated from the paclitaxel in subsequent purification. The chromatographic fraction of A2O3 was purified by a subsequent reversed-phase column chromatography, employing a novel uniform porous microsphere, named PST, as the packing material. Combination of the two steps of column chromatography and one step of crystallization was able to purify paclitaxel, from 0.46% to more than 98% with the total recovery- of 71%. This integrated chromatographic procedure was reproducible, efficient, and simple to use. [ABSTRACT FROM AUTHOR]

A stable and bio-compatible w/o nano-emulsion was developed as adjuvant for foot and mouth disease (FMD) vaccine with isopropyl myristate as oil phase, polyglycerol polyricinoleate, and Tween 80 as surfactants. Dissolving Tween 80 in aqueous phase decreased the droplet size and improved stability of the emulsion through narrowing size distribution, increasing viscosity, and reducing the interfacial tension between oil and water. The nano-emulsion was then formulated with inactivated FMD virus and ovalbumin to investigate its potential application as an adjuvant. Compared with commercial ISA-206 adjuvant, the novel w/o nano-emulsion was able to induce both humoral- and cell-mediated immune response. [ABSTRACT FROM AUTHOR]

Context: PEGylated hemoglobin (Hb) is a promising oxygen therapeutic agent for clinical application. However, it suffered from structural perturbation, functional instability and methemoglobin (metHb) formation. Objective: To improve the structural, functional, physical and anti-oxidation properties of the PEGylated Hb. Materials and methods: PEGylation of Hb with CO binding (HbCO) was conducted using maleimide and acylation chemistry, respectively. Physical and chemical parameters were measured for Hb samples. The circular dichroism spectra, dynamic light scattering and analytical ultracentrifugation were used to investigate the structure and conformation of PEGylated HbCO. Results: CO binding can inhibit the autoxidation of the PEGylated Hb, structurally stabilize its tetramer and improve its thermal and pH stability. Importantly, the circular dichroism spectra showed that CO binding can decrease the structural perturbation of Hb induced by PEGylation. The PEGylated HbCO with CO release showed slightly higher oxygen-delivery capacity than the PEGylated Hb. The PEGylated HbCO did not show metHb formation after 30-day storage at 4°C. Discussion and conclusion: CO binding structurally stabilized the PEGylated Hb, abolished its metHb formation, and significantly increased its physical stability. In particular, it also avoided the perturbation of PEG chains on the heme microenvironment. The functional property of the PEGylated HbCO can be maintained during its long-term storage, which is of great significance for field transfusion. [ABSTRACT FROM AUTHOR]

Human plasma fraction IV is an intermediate precipitate during the production of human serum albumin using cold ethanol method. Haptoglobin locates in this fraction can be purified for various applications. A new process integration of polyethylene glycol (PEG) precipitation and ion-exchange chromatography (IEC) was developed for purification of haptoglobin, which could effectively purify the haptoglobin from 16.6% to 95%. The recovery of the new process was 58.2% in comparison to 30.3% of the conventional affinity chromatography. Furthermore, 175 mg haptoglobin production in a scaled-up process showed the method to be simple, fast, and low-cost. [ABSTRACT FROM AUTHOR]

The gelatin plasma substitute is often polydisperse and heterogenous, making it difficult to determine the elimination rate and half-life in the body. In this study, one method was developed based on quantitative determination of hydroxyproline derivatives. Two plasma substitutes were prepared by succinylation and genipin-crosslinking, respectively. After transfusion, the blood samples were hydrolyzed and derivatized, and then analyzed by HPLC. A two-phase exponential association equation was used for fitting the time-concentration curves. The results indicated that this method could be used for quantitative determination of gelatin in blood, and the pharmacokinetic parameters such as elimination rate and half-life. [ABSTRACT FROM AUTHOR]

A solid phase conjugation process was developed for attachment of polyethylene glycol to hemoglobin molecule. Bovine hemoglobin was loaded onto an ion exchange chromatography column and adsorbed by the solid medium. Succinimidyl carbonate mPEG was introduced in the mobile phase after the adsorption. Pegylation took place between the hemoglobin on the solid phase, and the pegylation reagent in the liquid phase. A further elution was carried out to separate the pegylated and the unpegylated protein. Analysis by HPSEC, SDS-PAGE, and MALLS demonstrated that the fractions eluted from the solid phase contained well-defined components. Pegylated hemoglobin with one PEG chain was obtained with the yield of 75%, in comparison to the yield of 30% in the liquid phase pegylation. The P50 values of the mono-pegylated hemoglobin, prepared with SC-mPEG 5kDa, 10kDa and 20kDa, were 19.97, 20.23 and 20.54 mmHg, which were much closer to the value of red blood cells than that of pegylated hemoglobin prepared with the conventional method. [ABSTRACT FROM AUTHOR]

A rapid, facile, and environmentally friendly process was developed for purification of huperzine A (HupA) and huperzine B (HupB) from the Chinese traditional herb Huperzia serrata . The process consisted of two steps of preparative low-pressure liquid chromatography (LPLC) on two polystyrene based resins, successively. The first step removed a large amount of impurities and captured HupA and HupB using Amberlite XAD-4 from the herbal extraction prepared by 1% aqueous H 2 SO 4 . This step was more efficient than multi-cycle liquid-liquid extraction as an initial separation step. The second step was able to separate HupA and HupB, employing a novel uniform polystyrene based porous microsphere named PST as the packing material. The PST column demonstrated a better separation and shorter run time compared with a commercial C 18 column. The mobile phases used in both LPLC's simply consisted of water and ethanol that are considered to be of low toxicity. Combination of the XAD-4 and PST chromatography and one step of crystallization enabled purification of HupA and HupB from 0.18% and 0.08% to 98.2% and 98.8%, respectively, with total recoveries of 82.8% and 84.3%. [ABSTRACT FROM AUTHOR]