Evaluating the Bioavailability of Carbamazepine Using a Novel SNEDDS Formulation

Carbamazepine (CBZ) is an anticonvulsant drug primarily used to treat epilepsy, bipolar disorder, trigeminal and glossopharyngeal neuralgia. CBZ is a lipophilic, poorly soluble drug that belongs to the class-2 category according to the Biopharmaceutics Classification System. As a class-2 drug, the plasma concentration of CBZ is limited by its ability to diffuse across biological membranes. To increase its bioavailability, different methods such as crystal modifications, particle size reduction, amorphization, cyclodextrin complexation, pH modification, and self-emulsification were explored. Of these methods, Self Nano Emulsifying Drug Delivery Systems (SNEDDS) have shown to reduce particle size of CBZ molecules and improve its solubility. However, the bioavailability of CBZ administered as SNEDDS are not yet investigated. Given this background, the current study proposes to evaluate the bioavailability of these novel drug delivery systems using a rat model. The study is designed as a randomized controlled crossover experiment using 10-12 Sprague-Dawley rats divided equally into two groups. For this study, blood samples will be collected at 5, 10, 15, 20, 30, 45, 60, 90, and 120 minutes after administering two different formulations of CBZ nanoemulsions and stored at -20°C until ready for analysis. Plasma concentrations of CBZ will be determined by HPLC method. An unpaired t-test will be used to compare the significance between the two sets of data

Evaluating the Bioavailability of Carbamazepine Using a Novel SNEDDS Formulation

Central to the mechanism of how drugs work are the concepts of solubility and bioavailability. Drugs enter the body via absorption into the bloodstream, arrive at the target location, and bind to receptors to cause an effect. Drugs need to be soluble enough to pass through the cell membrane to enter and exit the bloodstream. Higher solubility generally correlates to higher bioavailability. Additionally, the smaller the particle size, the easier the drug will pass through the membrane into the blood plasma. Researchers have designed a system to categorize solubility class: Class I being high permeability and high solubility, Class II high permeability and low solubility, Class III low permeability and high solubility, and Class IV low permeability and low solubility. The study will use a Class II anticonvulsant, carbamazepine (CBZ). CBZ is a suitable candidate for this study because it requires a higher bioavailability due to its need to cross the blood brain barrier and act on the trigeminal nucleus. To increase bioavailability researchers have tried crystal modifications, particle size reduction, amorphization, cyclodextrin complexation, pH modification, and self-emulsification. These methods have been successful at increasing bioavailability, but this experiment will focus on reducing particle size into a new self-emulsifying formulation. In particular, the formulation of CBZ in this study is a self nano-emulsifying drug delivery system (SNEDDS), which shows more promise than previous methods to increase bioavailability. This study will create a SNEDDS formulation as a nasal nebulizer mist delivery and compare it to a FDA approved oral suspension using a crossover rat model design. Sixteen Sprague-Dawley rats will be ordered through Central State University and normalized to the study environment for a minimum of one week. Pending IACUC approval from Central State University, the tail vein method will be used to collect blood samples. The samples will be stored until needed for analysis using ELISA, enzyme-linked immunosorbent assay, which will be used to determine the concentration of CBZ in blood plasma

Multi-scale Analysis of Bone Chemistry, Morphology and Mechanics in the oim Model of Osteogenesis Imperfecta

Osteogenesis imperfecta is a congenital disease commonly characterized by brittle bones and caused by mutations in the genes encoding Type I collagen, the single most abundant protein produced by the body. The oim model has a natural collagen mutation, converting its heterotrimeric structure (two α1 and one α2 chains) into α1 homotrimers. This mutation in collagen may impact formation of the mineral, creating a brittle bone phenotype in animals. Femurs from male wild type (WT) and homozygous (oim/oim) mice, all at 12 weeks of age, were assessed using assays at multiple length scales with minimal sample processing to ensure a near-physiological state. Atomic force microscopy (AFM) demonstrated detectable differences in the organization of collagen at the nanoscale that may partially contribute to alterations in material and structural behavior obtained through mechanical testing and reference point indentation (RPI). Changes in geometric and chemical structure obtained from µ-Computed Tomography and Raman spectroscopy indicate a smaller bone with reduced trabecular architecture and altered chemical composition. Decreased tissue material properties in oim/oim mice are likely driven by changes in collagen fibril structure, decreasing space available for mineral nucleation and growth, as supported by a reduction in mineral crystallinity. Multi-scale analyses of this nature offer much in assessing how molecular changes compound to create a degraded, brittle bone phenotype

Investigating the physical properties of transiting hot Jupiters with the 1.5-m Kuiper Telescope

We present new photometric data of 11 hot Jupiter transiting exoplanets (CoRoT-12b, HAT-P-5b, HAT-P-12b, HAT-P-33b, HAT-P-37b, WASP-2b, WASP-24b, WASP-60b, WASP-80b, WASP-103b, XO-3b) in order to update their planetary parameters and to constrain information about their atmospheres. These observations of CoRoT-12b, HAT-P-37b and WASP-60b are the first follow-up data since their discovery. Additionally, the first near-UV transits of WASP-80b and WASP-103b are presented. We compare the results of our analysis with previous work to search for transit timing variations (TTVs) and a wavelength dependence in the transit depth. TTVs may be evidence of a third body in the system and variations in planetary radius with wavelength can help constrain the properties of the exoplanet's atmosphere. For WASP-103b and XO-3b, we find a possible variation in the transit depths that may be evidence of scattering in their atmospheres. The B-band transit depth of HAT-P-37b is found to be smaller than its near-IR transit depth and such a variation may indicate TiO/VO absorption. These variations are detected from 2-4.6$\sigma$, so follow-up observations are needed to confirm these results. Additionally, a flat spectrum across optical wavelengths is found for 5 of the planets (HAT-P-5b, HAT-P-12b, WASP-2b, WASP-24b, WASP-80b), suggestive that clouds may be present in their atmospheres. We calculate a refined orbital period and ephemeris for all the targets, which will help with future observations. No TTVs are seen in our analysis with the exception of WASP-80b and follow-up observations are needed to confirm this possible detection.Comment: 18 pages, 7 figures, 9 Tables. Light Curves available online. Accepted to MNRAS (2017 August 25

Anti-CfaE nanobodies provide broad cross-protection against major pathogenic enterotoxigenic Escherichia coli strains, with implications for vaccine design

Enterotoxigenic Escherichia coli (ETEC) is estimated to cause approximately 380,000 deaths annually during sporadic or epidemic outbreaks worldwide. Development of vaccines against ETEC is very challenging due to the vast heterogeneity of the ETEC strains. An effective vaccines would have to be multicomponent to provide coverage of over ten ETEC strains with genetic variabilities. There is currently no vaccine licensed to prevent ETEC. Nanobodies are successful new biologics in treating mucosal infectious disease as they recognize conserved epitopes on hypervariable pathogens. Cocktails consisting of multiple nanobodies could provide even broader epitope coverage at a lower cost compared to monoclonal antibodies. Identification of conserved epitopes by nanobodies can also assist reverse engineering of an effective vaccine against ETEC. By screening nanobodies from immunized llamas and a naive yeast display library against adhesins of colonization factors, we identified single nanobodies that show cross-protective potency against eleven major pathogenic ETEC strains in vitro. Oral administration of nanobodies led to a significant reduction of bacterial colonization in animals. Moreover, nanobody-IgA fusion showed extended inhibitory activity in mouse colonization compared to commercial hyperimmune bovine colostrum product used for prevention of ETEC-induced diarrhea. Structural analysis revealed that nanobodies recognized a highly-conserved epitope within the putative receptor binding region of ETEC adhesins. Our findings support further rational design of a pan-ETEC vaccine to elicit robust immune responses targeting this conserved epitope

A cross-reactive human IgA monoclonal antibody blocks SARS-CoV-2 spike-ACE2 interaction

COVID-19 caused by SARS-CoV-2 has become a global pandemic requiring the development of interventions for the prevention or treatment to curtail mortality and morbidity. No vaccine to boost mucosal immunity, or as a therapeutic, has yet been developed to SARS-CoV-2. In this study, we discover and characterize a cross-reactive human IgA monoclonal antibody, MAb362. MAb362 binds to both SARS-CoV and SARS-CoV-2 spike proteins and competitively blocks ACE2 receptor binding, by overlapping the ACE2 structural binding epitope. Furthermore, MAb362 IgA neutralizes both pseudotyped SARS-CoV and SARS-CoV-2 in 293 cells expressing ACE2. When converted to secretory IgA, MAb326 also neutralizes authentic SARS-CoV-2 virus while the IgG isotype shows no neutralization. Our results suggest that SARS-CoV-2 specific IgA antibodies, such as MAb362, may provide effective immunity against SARS-CoV-2 by inducing mucosal immunity within the respiratory system, a potentially critical feature of an effective vaccine

Ribosome-associated vesicles: A dynamic subcompartment of the endoplasmic reticulum in secretory cells

The endoplasmic reticulum (ER) is a highly dynamic network of membranes. Here, we combine live-cell microscopy with in situ cryo–electron tomography to directly visualize ER dynamics in several secretory cell types including pancreatic β-cells and neurons under near-native conditions. Using these imaging approaches, we identify a novel, mobile form of ER, ribosome-associated vesicles (RAVs), found primarily in the cell periphery, which is conserved across different cell types and species. We show that RAVs exist as distinct, highly dynamic structures separate from the intact ER reticular architecture that interact with mitochondria via direct intermembrane contacts. These findings describe a new ER subcompartment within cells

BCAA catabolism in brown fat controls energy homeostasis through SLC25A44.

Branched-chain amino acid (BCAA; valine, leucine and isoleucine) supplementation is often beneficial to energy expenditure; however, increased circulating levels of BCAA are linked to obesity and diabetes. The mechanisms of this paradox remain unclear. Here we report that, on cold exposure, brown adipose tissue (BAT) actively utilizes BCAA in the mitochondria for thermogenesis and promotes systemic BCAA clearance in mice and humans. In turn, a BAT-specific defect in BCAA catabolism attenuates systemic BCAA clearance, BAT fuel oxidation and thermogenesis, leading to diet-induced obesity and glucose intolerance. Mechanistically, active BCAA catabolism in BAT is mediated by SLC25A44, which transports BCAAs into mitochondria. Our results suggest that BAT serves as a key metabolic filter that controls BCAA clearance via SLC25A44, thereby contributing to the improvement of metabolic health