An investigation of the stability and diffusivity of flexible lipid vesicles for transdermal insulin delivery

Gemstone Team No More NeedlesFlexible lipid vesicles have the potential of complementing or even replacing traditional needle injection methods for insulin delivery. Vesicles are made flexible by the incorporation of a chemical surfactant which may also hinder their stability. We studied the changes in the size and apparent flexibility of vesicles with varying surfactant concentrations over time and the effects these changes have on vesicle diffusion. We found that increased surfactant concentrations lead to greater size fluctuations. In addition, we witnessed a significant decrease in the flexibility of vesicles over six weeks, while the diffusivity of surfactant infused liposomes increased over a single week. Our data suggests that while surfactants are necessary in vesicles for transdermal drug delivery, their long-term stability is uncertain. Using our diffusion data, we developed a model to estimate the insulin delivering capacity of a hypothetical insulin patch which has the potential to stabilize vesicles for extended periods of time

ppk23-Dependent Chemosensory Functions Contribute to Courtship Behavior in Drosophila melanogaster

Insects utilize diverse families of ion channels to respond to environmental cues and control mating, feeding, and the response to threats. Although degenerin/epithelial sodium channels (DEG/ENaC) represent one of the largest families of ion channels in Drosophila melanogaster, the physiological functions of these proteins are still poorly understood. We found that the DEG/ENaC channel ppk23 is expressed in a subpopulation of sexually dimorphic gustatory-like chemosensory bristles that are distinct from those expressing feeding-related gustatory receptors. Disrupting ppk23 or inhibiting activity of ppk23-expressing neurons did not alter gustatory responses. Instead, blocking ppk23-positive neurons or mutating the ppk23 gene delayed the initiation and reduced the intensity of male courtship. Furthermore, mutations in ppk23 altered the behavioral response of males to the female-specific aphrodisiac pheromone 7(Z), 11(Z)-Heptacosadiene. Together, these data indicate that ppk23 and the cells expressing it play an important role in the peripheral sensory system that determines sexual behavior in Drosophila

Affinity binding of antibodies to supermacroporous cryogel adsorbents with immobilized protein A for removal of anthrax toxin protective antigen

Polymeric cryogels are efficient carriers for the immobilization of biomolecules because of their unique macroporous structure, permeability, mechanical stability and different surface chemical functionalities. The aim of the study was to demonstrate the potential use of macroporous monolithic cryogels for biotoxin removal using anthrax toxin protective antigen (PA), the central cell-binding component of the anthrax exotoxins, and covalent immobilization of monoclonal antibodies. The affinity ligand (protein A) was chemically coupled to the reactive hydroxyl and epoxy-derivatized monolithic cryogels and the binding efficiencies of protein A, monoclonal antibodies to the cryogel column were determined. Our results show differences in the binding capacity of protein A as well as monoclonal antibodies to the cryogel adsorbents caused by ligand concentrations, physical properties and morphology of surface matrices. The cytotoxicity potential of the cryogels was determined by an in vitro viability assay using V79 lung fibroblast as a model cell and the results reveal that the cryogels are non-cytotoxic. Finally, the adsorptive capacities of PA from phosphate buffered saline (PBS) were evaluated towards a non-glycosylated, plant-derived human monoclonal antibody (PANG) and a glycosylated human monoclonal antibody (Valortim®), both of which were covalently attached via protein A immobilization. Optimal binding capacities of 108 and 117 mg/g of antibody to the adsorbent were observed for PANG attached poly(acrylamide-allyl glycidyl ether) [poly(AAm-AGE)] and Valortim® attached poly(AAm-AGE) cryogels, respectively, This indicated that glycosylation status of Valortim® antibody could significantly increase (8%) its binding capacity relative to the PANG antibody on poly(AAm-AGE)-protien-A column (p < 0.05). The amounts of PA which remained in the solution after passing PA spiked PBS through PANG or Valortim bound poly(AAm-AGE) cryogel were significantly (p < 0.05) decreased relative to the amount of PA remained in the solution after passing through unmodified as well as protein A modified poly(AAm-AGE) cryogel columns, indicates efficient PA removal from spiked PBS over 60 min of circulation. The high adsorption capacity towards anthrax toxin PA of the cryogel adsorbents indicated potential application of these materials for treatment of Bacillus anthracis infection

Proceedings of the Thirteenth International Society of Sports Nutrition (ISSN) Conference and Expo

Meeting Abstracts: Proceedings of the Thirteenth International Society of Sports Nutrition (ISSN) Conference and Expo Clearwater Beach, FL, USA. 9-11 June 201

Immune Response in Tilapia, Oreochromis niloticus, Induced by the Surface Immunogenic Protein (Sip) of Streptococcus agalactiae

The main aim of this study was to demonstrate that the surface immunogenic protein (Sip) of the aquatic pathogen Streptococcus agalactiae is a potential candidate for vaccine development for Oreochromis niloticus. In this study, a Sip was identified. Alignment analysis indicated that the Sip protein was highly homologous with Sip proteins from other S. agalactiae isolated from humans (99%). SDS-PAGE procedure indicated that the Sip protein was successfully expressed in Escherichia coli BL21 (DE3). The recombinant Sip protein was purified by affinity chromatography, and the mouse anti-Sip serum was produced. Tilapia Oreochromis niloticus were vaccinated with Sip, and immunogenicity was confirmed by subsequent western blotting. Enzyme-linked immunosorbent assay (ELISA) analysis demonstrated that Sip produced an observable antibody response in all sera of the vaccinated fish. The relative percentage survival (RPS) value for the Sip vaccine was 90.62. Tilapia vaccinated with Sip produced specific antibodies, and were highly resistant to infection by the virulent S. agalactiae. These results indicate that Sip is an effective vaccine candidate against S. agalactiae for tilapia, Oreochromisniloticus

An Improved Method of an Image Mosaic of a Tea Garden and Tea Tree Target Extraction

UAV may be limited by its flight height and camera resolution when aerial photography of a tea garden is carried out. The images of the tea garden contain trees and weeds whose vegetation information is similar to tea tree, which will affect tea tree extraction for further agricultural analysis. In order to obtain a high-definition large field-of-view tea garden image that contains tea tree targets, this paper (1) searches for the suture line based on the graph cut method in the image stitching technology; (2) improves the energy function to realize the image stitching of the tea garden; and (3) builds a feature vector to accurately extract tea tree vegetation information and remove unnecessary variables, such as trees and weeds. By comparing this with the manual extraction, the algorithm in this paper can effectively distinguish and eliminate most of the interference information. The IOU in a single mosaic image was more than 80% and the omissions account was 10%. The extraction results in accuracies that range from 84.91% to 93.82% at the different height levels (30 m, 60 m and 100 m height) of single images. Tea tree extraction accuracy rates in the mosaic images are 84.96% at a height of 30 m, and 79.94% at a height of 60 m

Zein-Functionalized MCM-41 Silica Nanoparticles with Enzyme-Responsive for Controlled Release in Antibacterial Activity

This research provided a novel enzyme-responsive antimicrobial carrier aiming at overcoming the volatile loss of active antibacterial components, by employing mesoporous silica nanoparticles (MCM-41) as the matrix of encapsulation and Zein as the molecular gate. Since Zein could be consumed by bacteria, Zein-functionalized MCM-41 acted as an enzyme-responsive gate and improved the controlled-release capacity. The results showed that the amount of capsaicin released from Zein-functionalized MCM-41 without bacteria was quite low compared with the essential oils liberated with bacteria. This validated that the delivery of capsaicin was hampered by Zein and the existence of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) promoted the release of encapsulated cargo. The release rate of capsaicin in Zein-functionalized MCM-41 climbed with the growth velocity of bacteria. These functions were realized in the form of controlled diffusion of essential oils encapsulated in MCM-41 by electrostatic interaction, and Zein was performed by both covalent bonding interaction and electrostatic interaction. Zein-functionalized MCM-41 was 2.4 times more effective in killing E. coli and 1.2 times more effective in inhibiting S. aureus than an equal amount of free capsaicin, and possessed a long-lasting antibacterial activity. The responsive antimicrobial material might be used as a promising preservative in the food industry for antimicrobial activity enhancement

Synthesis of Folic Acid-Modified DOX@ZIF-8 Nanoparticles for Targeted Therapy of Liver Cancer

The effective chemotherapy treatment for liver cancer patients remains an urgent issue due to the difficulty in precisely delivering drugs to the tumor site. The targeted delivery of drugs by nanoparticles is a promising strategy to address this problem. However, the fabrication of drug targeted delivery nanosystem still remains a major challenge. In this study, a novel folic acid-functionalized (doxorubicin, DOX) DOX@ZIF-8 nanoparticles (DOX@ZIF-8-FA) were prepared as a liver cancer-targeted drug delivery system. The delivery nanosystem exhibited a high drug loading capacity (15.7 wt%) and presented excellent drug-sustained release performances and good pH-responsive properties. Compared with free DOX and DOX@ZIF-8 nanoparticles, the DOX@ZIF-8-FA nanoparticles displayed much higher anticancer efficiency in HepG2 cells, suggesting that the folic acid-functionalized DOX@ZIF-8 nanoparticles have promising applications in targeted treatment of cancer cells