Amphiphilic polyanhydride nanoparticles stabilize bacillus anthracis protective antigen

Advancements toward an improved vaccine against Bacillus anthracis, the causative agent of anthrax, have focused on formulations composed of the protective antigen (PA) adsorbed to aluminum hydroxide. However, due to the labile nature of PA, antigen stability is a primary concern for vaccine development. Thus, there is a need for a delivery system capable of preserving the immunogenicity of PA through all the steps of vaccine fabrication, storage, and administration. In this work, we demonstrate that biodegradable amphiphilic polyanhydride nanoparticles, which have previously been shown to provide controlled antigen delivery, antigen stability, immune modulation, and protection in a single dose against a pathogenic challenge, can stabilize and release functional PA. These nanoparticles demonstrated polymer hydrophobicity-dependent preservation of the biological function of PA upon encapsulation, storage (over extended times and elevated temperatures), and release. Specifically, fabrication of amphiphilic polyanhydride nanoparticles composed of 1,6-bis(p-carboxyphenoxy)hexane and 1,8-bis(p-carboxyphenoxy)-3,6- dioxaoctane best preserved PA functionality. These studies demonstrate the versatility and superiority of amphiphilic nanoparticles as vaccine delivery vehicles suitable for long-term storage

Global Functional Atlas of \u3cem\u3eEscherichia coli\u3c/em\u3e Encompassing Previously Uncharacterized Proteins

One-third of the 4,225 protein-coding genes of Escherichia coli K-12 remain functionally unannotated (orphans). Many map to distant clades such as Archaea, suggesting involvement in basic prokaryotic traits, whereas others appear restricted to E. coli, including pathogenic strains. To elucidate the orphans’ biological roles, we performed an extensive proteomic survey using affinity-tagged E. coli strains and generated comprehensive genomic context inferences to derive a high-confidence compendium for virtually the entire proteome consisting of 5,993 putative physical interactions and 74,776 putative functional associations, most of which are novel. Clustering of the respective probabilistic networks revealed putative orphan membership in discrete multiprotein complexes and functional modules together with annotated gene products, whereas a machine-learning strategy based on network integration implicated the orphans in specific biological processes. We provide additional experimental evidence supporting orphan participation in protein synthesis, amino acid metabolism, biofilm formation, motility, and assembly of the bacterial cell envelope. This resource provides a “systems-wide” functional blueprint of a model microbe, with insights into the biological and evolutionary significance of previously uncharacterized proteins

Design and evaluation of pathogen-mimicking polyanhydride delivery platforms for drug and vaccine applications

Vaccines and antibiotics have had a profound impact on human and animal health in the last century. Despite their success, there are several disadvantages associated with current regimens, including multiple immunizations that result in poor patient compliance, high reactogenicity, unpleasant side effects, and poor efficacy against intracellular pathogens. In this regard, innovative delivery platforms can facilitate the development of effective single-dose treatment regimens to control emerging and re-emerging infectious diseases. The work presented in this dissertation describes how rational design principles can be successfully employed to develop targeted polyanhydride platforms for drug and vaccine delivery. Initial studies sought to define the interactions of various polyanhydride micro- and nanoparticle formulations with antigen presenting cells (APCs), a type of immune cell critical to the initiation of immune responses. Experiments focused on particle internalization, uptake mechanism(s), and intracellular trafficking revealed striking chemistry and size dependent effects. Knowledge gained from these studies was then used to strategically select specific particle sizes and chemistries to test the efficacy of doxycycline-loaded particles against an in vitro infection with the intracellular pathogen Brucella. Subsequent chapters in this dissertation detail how a multidisciplinary approach utilizing tools from cell biology, immunology, biomaterials engineering, carbohydrate chemistry, and informatics analysis delineated the complex patterns observed during host-pathogen interactions. These observations were then used to identify the properties of polyanhydride nanoparticles that mimicked the ability of bacterial pathogens to induce a robust immune response. Specifically, surface functionalization, including the addition of carbohydrates, made nanoparticles more pathogen-mimicking in terms of their intracellular fate, persistence and APC activation compared to Yersinia pestis or Escherichia coli. Carbohydrate functionalization also enhanced microparticle internalization by targeting the C-type lectin receptors present on APCs. Studies were also performed to evaluate the effect of vaccine antigen functionalization in combination with the polyanhydride nanoparticle platform. Modification of the plague antigen F1-V with α-galactose induced T cell expansion as well as a high titer, high avidity antibody response with broad epitope recognition of F1-V peptides when administered with polyanhydride nanoparticles. In summary, the studies described herein support the rational design and selection of delivery platforms to meet the needs of a spectrum of biomedical applications, including drug and vaccine delivery

Water Efficiency and Management in Green Building: A Review

Water is the most important compound worldwide for life support and other varied human activities. The shortage for these specific activities demands the need for air, river, waste and water disposal, reservation and transportation to produce portable water. These studies were planned to assess the value of water conservation and quality, and the level of distribution of criteria and points through green building ranking systems. When groups, criteria and distribution of points were evaluated for ranking schemes. The analysis reveals that water is a significant category because it is included in all rating schemes and within the rating schemes have appreciable criteria and the allocation level. The difference in rank, criteria, and points distribution is focused on the social, cultural, and environmental interests of all stakeholders of the different countries. The Green Ship and Green Star SA 's highest parameters and points indicate the need for effective water production and delivery throughout the society as well as the house. While in Green Mark and BEAM is due to lack of enough fresh water for daily activities as well as building construction. As a consequence of developments in renewable water production and delivery in the respective countries, the lowest in the BREEAM, Green Star NZ and LEED has been. The study harmonized criteria included the whole sustainable building environment evaluation in terms of water supply, delivery, and use for countries establishing ranking schemes

A systems approach to designing next generation vaccines: Combining α-galactose modified antigens with nanoparticle platforms

Innovative vaccine platforms are needed to develop effective countermeasures against emerging and re-emerging diseases. These platforms should direct antigen internalization by antigen presenting cells and promote immunogenic responses. This work describes an innovative systems approach combining two novel platforms, αGalactose (αGal)-modification of antigens and amphiphilic polyanhydride nanoparticles as vaccine delivery vehicles, to rationally design vaccine formulations. Regimens comprising soluble αGal-modified antigen and nanoparticle-encapsulated unmodified antigen induced a high titer, high avidity antibody response with broader epitope recognition of antigenic peptides than other regimen. Proliferation of antigen-specific CD4 + T cells was also enhanced compared to a traditional adjuvant. Combining the technology platforms and augmenting immune response studies with peptide arrays and informatics analysis provides a new paradigm for rational, systems-based design of next generation vaccine platforms against emerging and re-emerging pathogens

A low-leakage, low-loss transformer structure for high-frequency applications

Designing transformers for HF applications with low magnetizing inductance is challenging because of increased core and copper losses and losses due to stored energy in the leakage inductance. Many converter topologies and applications cannot absorb the leakage inductance of the transformer, so designs that minimize leakage are very valuable. We propose a transformer structure which has low leakage inductance and low losses making it suitable for applications requiring energy storage transformers or coupled inductors. The transformer structure achieves near zero MMF drop across the window which results in a design with low leakage. It achieves current conduction along most of the skin of the conductors and is also suitable for high turns ratio applications because of its ability to achieve equal current sharing between paralleled turns. Because of these reasons, the transformer achieves low conduction losses without requiring the use of litz wire. Step-by-step design guidelines are proposed to achieve a roughly optimized structure and the design of a transformer with L [subscript mag] =105nH and 1-10 turns ratio for use in a 400W, 20-400V coupled-inductor based boost converter is presented.Electrical and Computer Engineerin

Antidiabetic and nephroprotective effect of tectona grandis linn. In alloxan induced diabetes

In the present study, effect of ethanolic extract of bark of Tectona grandis Linn. (TG) was evaluated using alloxan induced diabetes and associated renal complication. The diabetes was induced by administration of alloxan to the rats at the dose of 140 mg/kg, i.p. TG was administered to diabetic animals for six weeks and various biochemical parameters in blood and urine (plasma glucose, serum albumin, total protein, and creatinine, urine total protein, urine albumin), tissue parameters (cholesterol and triglyceride in kidney homogenate) and % change in body weight were evaluated along with histopathological study. In present study diabetic animals treated with TG showed significant reduction in the elevated level of plasma glucose (p<0.01) when compared with diabetic control. While considering renal parameters, diabetic animals treated with TG showed significant decrease in serum creatinine (p<0.05), urine albumin and urine total protein levels (p<0.01) and significant increase in serum albumin, total protein and % change in body weight (p<0.01) when compared with diabetic control. Diabetic control showed significant increase in total cholesterol and triglyceride accumulation in kidney, while diabetic animals treated with TG showed significant decrease in levels of total cholesterol (p<0.01) and triglyceride (p<0.05) in the kidney when compared with diabetic control. Diabetic control showed significant mark of glomerulosclerosis and hyalinization which occurs because of severe diabetic condition (diabetic nephropathy). Diabetic groups treated with TG showed absence of the sclerotic lesions produced by diabetic condition. Hence, the results obtained in the present study indicate that Tectona grandis has the potential to treat diabetes mellitus and prevent the associated renal damage

Phyto-assisted synthesis of Silver nanoparticles using Tinospora cordifolia leaf extract and their antibacterial activity: An ecofriendly approach

To meet the increasing demands for commercial nanoparticles new eco-friendly methods of synthesis are being discovered. Plant mediated synthesis of nanoparticles offers single step, easy extracellular synthesis of nanoparticles. We report the synthesis of antibacterial Silver nanoparticles using leaf extract of the medicinal plant, Tinospora cordifolia. The leaf extract was prepared by boiling chopped leaves of Tinospora cordifolia in deionized water for 10 min and filtering the mixture with Whatman filter paper No.1. The filtrate was used as a reducing agent and stabilising agent for AgNO3. On adding 1 mM solution of Silver nitrate to the leaf extract and stirring at 75 °C for 25 min, a change in colour from yellow-brown to brown-black specified the production of Silver nanoparticles. The formation of Silver nanoparticles was monitored by UV-visible spectroscopy and further characterization of the synthesized Silver nanoparticles was done by XRD studies. The antibacterial studies were performed on Gram negative and Gram positive pathogens, Salmonella typhi, Pseudomonas aeruginosa, Enterobacter aerogenes and Staphylococcus aureus, by agar well diffusion method, on Mueller Hinton agar medium. The Silver nanoparticles synthesized from Tinospora cordifolia leaf extract were found to have antimicrobial activity against these Gram negative and Gram positive pathogenic bacteria