Dendrimer Conjugation Enhances Tumor Penetration and Cell Kill of Doxorubicin in 3D Coculture Lung Cancer Models

Background: Doxorubicin (DOX) is a potent chemotherapeutic widely used for solid tumors (1). Despite high efficacy in 2D cell culture, DOX efficacy does not translate to in vivo lung cancer models (2). Major side effects such as cardiotoxicity may be alleviated with nano-based drug delivery systems (nanoDDS). However, tumor penetration of DOX and DOX-nanoDDS is largely unknown and is an additional barrier to effective clinical therapy (3). Here we describe a nanoDDS capable of enhancing the penetration of DOX. Methods: DOX was conjugated to generation 4 poly(amido-amine) dendrimers through (GFLG) tumor- liable bond. G4SA-GFLG-DOX was synthesized/characterized. spheroids were formed of (A549) lung adenocarcinoma cells and (3T3) fibroblasts. Spheroids were characterized for ECM components with immunohistochemistry. Confocal microscopy was used to evaluate the penetration, internalization, and colocalization of DOX and G4SA-GFLG-DOX. MTT assay and Caspase 3/7 to assess 2D and 3D cytotoxicity. Flow cytometry to determine cells uptake. Results: DOX conjugation to dendrimer resulted in G4SA-GFLG-DOX with ~5.5 DOX, 10±1 nm hydrodynamic diameter, and a -17±3 mV zeta-potential. Spheroids of (A549:3T3) were ECM- rich, developed ECM containing collagen-I, hyaluronan, laminin, and fibronectin. While DOX and G4SA-GFLG-DOX had similar toxicities in 2D model, G4SA-GFLG-DOX demonstrated a 3.1-fold greater penetration into spheroids compared to DOX and correlated to a greater efficacy as measured by caspase 3/7 activity. Also, flow cytometry showed higher uptake of G4SA- GFLG-DOX in cancer cells compared to fibroblasts. Conclusion: The work demonstrates enhanced penetration of DOX, via dendrimer conjugation, into an ECM- rich 3D lung cancer model. The enhanced penetration of G4SA-GFLG-DOX correlated with greater antitumor efficacy. Acknowledgements: We acknowledge partial financial support from the Center for Pharmaceutical Engineering and Sciences - School of Pharmacy at VCU. This study was supported by VCU Quest for Distinction and NSF (DRM #1508363). Microscopy was performed at the VCU Microscopy Facility, supported, in part, by funding from NIH-NCI Cancer Center Support Grant P30 CA016059. RA would like to acknowledge King Faisal University (KFU) and Saudi Arabian Cultural Mission (SACM) for a scholarship.https://scholarscompass.vcu.edu/gradposters/1091/thumbnail.jp

Yeast Features: Identifying Significant Features Shared Among Yeast Proteins for Functional Genomics

Background
High throughput yeast functional genomics experiments are revealing associations among tens to hundreds of genes using numerous experimental conditions. To fully understand how the identified genes might be involved in the observed system, it is essential to consider the widest range of biological annotation possible. Biologists often start their search by collating the annotation provided for each protein within databases such as the Saccharomyces Genome Database, manually comparing them for similar features, and empirically assessing their significance. Such tasks can be automated, and more precise calculations of the significance can be determined using established probability measures. 
Results
We developed Yeast Features, an intuitive online tool to help establish the significance of finding a diverse set of shared features among a collection of yeast proteins. A total of 18,786 features from the Saccharomyces Genome Database are considered, including annotation based on the Gene Ontology’s molecular function, biological process and cellular compartment, as well as conserved domains, protein-protein and genetic interactions, complexes, metabolic pathways, phenotypes and publications. The significance of shared features is estimated using a hypergeometric probability, but novel options exist to improve the significance by adding background knowledge of the experimental system. For instance, increased statistical significance is achieved in gene deletion experiments because interactions with essential genes will never be observed. We further demonstrate the utility by suggesting the functional roles of the indirect targets of an aminoglycoside with a known mechanism of action, and also the targets of an herbal extract with a previously unknown mode of action. The identification of shared functional features may also be used to propose novel roles for proteins of unknown function, including a role in protein synthesis for YKL075C.
Conclusions
Yeast Features (YF) is an easy to use web-based application (http://software.dumontierlab.com/yeastfeatures/) which can identify and prioritize features that are shared among a set of yeast proteins. This approach is shown to be valuable in the analysis of complex data sets, in which the extracted associations revealed significant functional relationships among the gene products.
&#xa

The application of predictive modelling for determining bio-environmental factors affecting the distribution of blackflies (Diptera: Simuliidae) in the Gilgel Gibe watershed in Southwest Ethiopia

Blackflies are important macroinvertebrate groups from a public health as well as ecological point of view. Determining the biological and environmental factors favouring or inhibiting the existence of blackflies could facilitate biomonitoring of rivers as well as control of disease vectors. The combined use of different predictive modelling techniques is known to improve identification of presence/absence and abundance of taxa in a given habitat. This approach enables better identification of the suitable habitat conditions or environmental constraints of a given taxon. Simuliidae larvae are important biological indicators as they are abundant in tropical aquatic ecosystems. Some of the blackfly groups are also important disease vectors in poor tropical countries. Our investigations aim to establish a combination of models able to identify the environmental factors and macroinvertebrate organisms that are favourable or inhibiting blackfly larvae existence in aquatic ecosystems. The models developed using macroinvertebrate predictors showed better performance than those based on environmental predictors. The identified environmental and macroinvertebrate parameters can be used to determine the distribution of blackflies, which in turn can help control river blindness in endemic tropical places. Through a combination of modelling techniques, a reliable method has been developed that explains environmental and biological relationships with the target organism, and, thus, can serve as a decision support tool for ecological management strategies

Heme oxygenase effect on mesenchymal stem cells action on experimental Alzheimer's disease

The objective is to evaluate the effect of heme oxygenase-1 (HO-1) enzyme inducer and inhibitor on Mesenchymal Stem Cells (MSCs) in Alzheimer disease. Materials and Methods: 70 female albino rats were divided equally into 7 groups as follows: group 1: healthy control; group 2: Aluminium chloride induced Alzheimer disease; group 3: induced Alzheimer rats that received intravenous injection of MSCs; group 4: induced Alzheimer rats that received MSCs and HO inducer cobalt protoporphyrin; group 5: induced Alzheimer rats that received MSCs and HO inhibitor zinc protoporphyrin; group 6: induced Alzheimer rats that received HO inducer; group7: induced Alzheimer rats that received HO inhibitor. Brain tissue was collected for HO-1, seladin-1 gene expression by real time polymerase chain reaction, heme oxygenase activity, cholesterol estimation and histopathological examination. Results: MSCs decreased the plaque lesions, heme oxygenase induction with stem cells also decreased plaque lesions however there was hemorrhage in the brain. Both heme oxygenase inducer alone or with stem cells increased seladin-1 expression and decreased cholesterol level. Conclusion: MSCs alone or with HO-1 induction exert a therapeutic effect against the brain lesion in Alzheimer’s disease possibly through decreasing the brain cholesterol level and increasing seladin-1 gene expression

Students preferences for teaching and exam delivery modes in accounting education post COVID 19 pandemic

The COVID-19 pandemic has sparked a revolution in the delivery of modules in higher education. This paper aims to answer the research question: What are the preferences of undergraduate accounting and finance students regarding teaching delivery and exam modes following the COVID-19 pandemic lockdown? Specifically, we focus on campus, online synchronous, and hybrid synchronous teaching delivery and exam modes. To address this research question, we conducted an online questionnaire surveying students at a U. K. university. Our data show that modules involving calculations, such as financial accounting, are preferred to be taught on campus, whereas theoretical modules like business law are preferred to be taught online. Additionally, the data reveal reasons for these preferences, including community learning, isolation, concentration, and access to recordings. This research contributes valuable insights into optimising accounting education. We advocate for flexibility in both teaching and exam delivery within accounting education, recognising the diverse needs of students

Newborn Screening for Homocystinuria Revealed a High Frequency of MAT I/III Deficiency in Iberian Peninsula

Acessível em: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4375120/Homocystinuria due to cystathionine β-synthase deficiency or "classical homocystinuria" is a rare autosomal recessive condition resulting in altered sulfur metabolism with elevated methionine and homocysteine in plasma and homocystine in urine. This condition is characterized by a high clinical heterogeneity, which contributes to late clinical diagnosis, usually only made after irreversible damage has occurred. Treatment is effective if started before clinical symptoms. The analysis of methionine levels by tandem mass spectrometry (MS/MS) allows the newborn screening for homocystinuria, but false-positive results can be frequently obtained and lead to the unwanted identification of methionine adenosyl transferase (MAT I/III) deficiency. This latter condition is biochemically characterized by isolated persistent hypermethioninemia, accompanied in some individuals with slightly elevated levels of homocysteine in plasma. A dominant form of MAT I/III deficiency, associated with mutation p.R264H, seems to be very frequent in the Iberian Peninsula and usually has a clinically benign course. Both these metabolic disorders are screened in Galicia and Portugal since the introduction of the MS/MS technology, in 2000 and 2004, respectively, resulting in the identification of three patients with classical homocystinuria and 44 patients with MAT I/III deficiency. All but one heterozygous parent of MAT I/III patients, identified with the p.R264H mutation, are healthy adults around the age of 30/40. The implementation of a second-tier test for homocysteine in dried blood spots would considerably reduce the number of MAT I/III-deficient patients identified and improve the specificity and positive predictive value for classical homocystinuria screening

Dynamic regulation of AtDAO1 and GH3 modulates auxin homeostasis

The hormone auxin is a key regulator of plant growth and development, and great progress has been made understanding auxin transport and signaling. Here we show that auxin metabolism and homeostasis are also regulated in a complex manner. The principal auxin degradation pathways in Arabidopsis include oxidation by AtDAO1/2 and conjugation by GH3s. Metabolic profiling of dao1-1 root tissues revealed a 50% decrease in the oxidation product oxIAA, an increase in the conjugated forms IAA-Asp and IAA-Glu of 438-fold and 240-fold respectively, while auxin remains close to wild type. By fitting parameter values to a mathematical model of these metabolic pathways we show that, in addition to reduced oxidation, both auxin biosynthesis and conjugation are increased in dao1-1. We then quantified gene expression in plantae, and found that transcripts of AtDAO1 and GH3 genes are increased in response to auxin, over different time scales and concentration ranges. Including this regulation of AtDAO1 and GH3 in an extended model reveals that auxin oxidation is more important for auxin homoeostasis at lower hormone concentrations, while auxin conjugation is most significant at high auxin levels. Finally, embedding our homeostasis model in a multicellular simulation to assess the spatial effect of the dao1-1 mutant shows that auxin increases in outer root tissues, in agreement with the dao1-1 mutant root hair phenotype. We conclude that auxin homeostasis is dependent on AtDAO1, acting in concert with GH3, to maintain auxin at optimal levels for plant growth and development