Identification and characterization of G4-DNA binding proteins from Tetrahymena thermophila

Alternative DNA conformations have been known to exist since before the elucidation of the double helix. The study of alternative DNA conformations formed by telomeric sequences has led to detailed studies of biologically relevant DNA capable of forming unusual structures. In order to understand the biological role of alternative DNA conformations formed by telomeric DNA, proteins which bind these structures have been identified and characterized;The initial portion of my research involved the identification of a protein from Tetrahymena thermophila which binds preferentially to parallel-stranded G-quartet structures. Competition and binding assays demonstrated that the protein, TGP (Tetrahymena G4 binding protein), binds to parallel G-DNA structures but not to antiparallel G-DNA structures or to non-G-DNA duplexes and single stranded oligonucleotides;This initial identification and characterization was followed up by attempts to purify TGP. Cation exchange and Y4-affinity chromatography partially purified two proteins (83 and 50 kDa) that coelute with peak TGP activity. UV cross-linking analysis confirmed the involvement of the 83 kDa protein as a main component of the TGP/G4-DNA complex

A Social and Ecological Approach to Mosquito Species Distribution Across Land Use in Bangor, Maine

Mosquitoes are ubiquitous pests and infectious disease vectors. However, not all mosquito species bite humans, or are competent pathogen vectors between bloodmeal hosts. Along with climatic variables like temperature and rainfall, mosquito species distribution is determined by aquatic habitat availability for juvenile mosquito development, and terrestrial habitat and host availability for adult mosquitoes. There is variation in the preferred aquatic habitat for gravid female oviposition and subsequent larval development. Some mosquito species’ oviposition and development are associated with ephemeral water sources (e.g., floodplains), others prefer more permanent water sources (e.g., bogs or vernal pools). Other mosquitoes have evolved to occupy small, artificial water containers (e.g., buckets, tires) that are associated with human-dominated areas. These environmental factors are impacted by human processes like agriculture and urbanization and affect human exposure to mosquitoes and mosquito-borne diseases (MBD). Human exposure is also affected by mosquito control (e.g., spraying pesticides, emptying water containers) or personal protective behaviors (e.g., using mosquito repellent, wearing protective clothing). This interaction of human and environmental factors that affect mosquito habitat allows us to approach this system using a social-ecological systems (SES) framework. Social-ecological approaches call for the components within a system and the relationships between them to be examined from an integrated perspective including cultural, political, economic and ecological viewpoints across spatial scales. The One Health framework is an SES which considers the health of animals, humans and the environment as interconnected and dependent on one another. The ecology of vector-borne diseases, and mosquito ecology specifically, are relevant topics for application of the One Health model due to the interactions of human and environmental variables. In this thesis, mosquito species distribution was examined at 40 sites across an urban to rural gradient and recreational parks in Bangor, Maine to understand how mosquito distribution is affected by land use in this region. Additionally, a Knowledge, Attitudes and Practices survey was distributed among participants at the 30 residential study sites to understand factors that affect engagement in mosquito control and personal protective behaviors. A mosquito habitat assessment was conducted at each participant’s property to integrate the analysis of social and ecological variables. Results show that mosquito abundance was significantly different across land use categories. Mosquito abundance was highest in recreational parks and rural residential areas. Among residential categories, rural sites had the most nuisance species mosquitoes, and the least vector species mosquitoes. Urban residential sites had the lowest mosquito abundance, but highest vector species abundance. Participant knowledge level was not associated with the amount of aquatic habitat suitable for larval mosquitoes, and participants were likely report mosquitoes as a nuisance on their properties, but unlikely to engage in control practices. These results indicate a possible mismatch between mosquito exposure, mosquito perceptions and engagement in control behaviors, which warrants further study. This thesis adds to a limited body of literature which examine mosquitoes from a social and ecological perspective in the United States, and this integrated perspective is important for understanding, protecting and improving public health issues related to mosquitoes

Contribution à l’étude Eco-éthologique du grand murin (Myotis myotis)

Les auteurs rapportent des observations effectuées dans une colonie de mise bas du Grand Murin (Myotis myotis ). Le gîte est situé dans les combles d’un édifice public. L’effectif de la colonie dépasse vers la mi-juin 2 000 sujets. Le baguage a porté, avant la saison d’observation, sur 1 074 sujets. Une technique est mise au point pour la réalisation d’opérations de baguage d’une certaine envergure. Les facteurs climatiques, extérieurs et intérieurs à la colonie, sont enregistrés à titre comparatif et les auteurs tentent d’établir une corrélation entre les variations de certains paramètres clima tiques et le comportement des Murins tout au long de la saison estivale. Le régime alimentaire est évoqué ; il semble que les proies préférentielles (Coléoptères) dépassent la taille de 18 mm. Un cas de canitie et des perforations du patagium sont décrits. Le rejet de jeunes par leur mère semble avoir été inhabituellement élevé pendant l’année 1970 qui peut être considérée comme pluvieuse sur le plan local

HIV-Nef and ADAM17-Containing Plasma Extracellular Vesicles Induce and Correlate with Immune Pathogenesis in Chronic HIV Infection

Peer reviewe

DC-ATLAS: a systems biology resource to dissect receptor specific signal transduction in dendritic cells

BACKGROUND: The advent of Systems Biology has been accompanied by the blooming of pathway databases. Currently pathways are defined generically with respect to the organ or cell type where a reaction takes place. The cell type specificity of the reactions is the foundation of immunological research, and capturing this specificity is of paramount importance when using pathway-based analyses to decipher complex immunological datasets. Here, we present DC-ATLAS, a novel and versatile resource for the interpretation of high-throughput data generated perturbing the signaling network of dendritic cells (DCs). RESULTS: Pathways are annotated using a novel data model, the Biological Connection Markup Language (BCML), a SBGN-compliant data format developed to store the large amount of information collected. The application of DC-ATLAS to pathway-based analysis of the transcriptional program of DCs stimulated with agonists of the toll-like receptor family allows an integrated description of the flow of information from the cellular sensors to the functional outcome, capturing the temporal series of activation events by grouping sets of reactions that occur at different time points in well-defined functional modules. CONCLUSIONS: The initiative significantly improves our understanding of DC biology and regulatory networks. Developing a systems biology approach for immune system holds the promise of translating knowledge on the immune system into more successful immunotherapy strategies

A Replication Study of GWAS-Derived Lipid Genes in Asian Indians: The Chromosomal Region 11q23.3 Harbors Loci Contributing to Triglycerides

Recent genome-wide association scans (GWAS) and meta-analysis studies on European populations have identified many genes previously implicated in lipid regulation. Validation of these loci on different global populations is important in determining their clinical relevance, particularly for development of novel drug targets for treating and preventing diabetic dyslipidemia and coronary artery disease (CAD). In an attempt to replicate GWAS findings on a non-European sample, we examined the role of six of these loci (CELSR2-PSRC1-SORT1 rs599839; CDKN2A-2B rs1333049; BUD13-ZNF259 rs964184; ZNF259 rs12286037; CETP rs3764261; APOE-C1-C4-C2 rs4420638) in our Asian Indian cohort from the Sikh Diabetes Study (SDS) comprising 3,781 individuals (2,902 from Punjab and 879 from the US). Two of the six SNPs examined showed convincing replication in these populations of Asian Indian origin. Our study confirmed a strong association of CETP rs3764261 with high-density lipoprotein cholesterol (HDL-C) (p = 2.03×10−26). Our results also showed significant associations of two GWAS SNPs (rs964184 and rs12286037) from BUD13-ZNF259 near the APOA5-A4-C3-A1 genes with triglyceride (TG) levels in this Asian Indian cohort (rs964184: p = 1.74×10−17; rs12286037: p = 1.58×10−2). We further explored 45 SNPs in a ∼195 kb region within the chromosomal region 11q23.3 (encompassing the BUD13-ZNF259, APOA5-A4-C3-A1, and SIK3 genes) in 8,530 Asian Indians from the London Life Sciences Population (LOLIPOP) (UK) and SDS cohorts. Five more SNPs revealed significant associations with TG in both cohorts individually as well as in a joint meta-analysis. However, the strongest signal for TG remained with BUD13-ZNF259 (rs964184: p = 1.06×10−39). Future targeted deep sequencing and functional studies should enhance our understanding of the clinical relevance of these genes in dyslipidemia and hypertriglyceridemia (HTG) and, consequently, diabetes and CAD

Master's thesis recital (tuba)

[Sonata, op. 1, no. 5, in C major / Benedetto Marcello ; arranged for tuba and piano -- Love song / Satoshi Yagisawa -- Concerto for tuba / Jörg Duda ; arranged for tuba and piano -- Sonatina for tuba and piano / Jacques Castérède -- Four romances on poems by Pushkin / Dmitri Shostakovich -- Suite Americana : for brass quintet / Enrique Crespo]MusicName of supervisor unavailabl

Operando-Gaschromatographie/Massenspektrometrie von Lithium-Ionen-Batterien während der Überladung und Post mortem-Analyse

Abweichender Titel nach Übersetzung der Verfasserin/des VerfassersDurch ihre außergewöhnlichen Eigenschaften wie hohe Energiedichte und große Stabilität im Verlauf vieler Lade- und Entladezyklen wurden Lithiumionenbatterien im Verlauf der letzten drei Jahrzehnte zu einer der am meisten verwendeten Technologien zur Speicherung von elektrischer Energie. Trotz der vielen Vorteile gibt es jedoch seit dem Beginn ihrer Kommerzialisierung Probleme mit Materialinstabilitäten und Sicherheitsaspekten, die im Zentrum der öffentlichen Aufmerksamkeit stehen. Die Zersetzung des Elektrolyten durch den Betrieb von Lithiumionenbatterien bei hohen Temperaturen, feuchter Umgebungsluft oder unkontrollierter Spannungszunahme (Überladung) kann zu starker Gasentstehung und weiters zur Entzündung und Explosion führen. Die Untersuchung der Gasformierung und der beteiligten Prozesse, sowie das Verständnis der Veränderung des Batteriematerials auf molekularer Ebene sind deshalb notwendig.Um die Fragestellung des entstehenden komplexen Gasgemisches aus Elektrolytzersetzungsprodukten beantworten zu können präsentiert sich die Kopplung der Gaschromatografie mit Massenspektrometrie durch ihre schnelle Identifikation und Detektion von Verbindungen als ideales Werkzeug. Operando GC-MS Experimente wurden im Münzbatteriemaßstab (d=15 mm, Eigenbau) und im „pouch cell“ Maßstab (durch Lithops s.r.l. bereitgestellt) durchgeführt. Helium wurde als Trägergas für den Transport der entstehenden flüchtigen Verbindungen in das GC-MS System verwendet, und die Spannung wurde mit konstantem Strom bis zur doppelten Abschaltspannung erhöht (Überladung). Für „pouch cell“ Experimente wurde zusätzlich das Erreichen einer Temperatur von 60°C und das Erreichen einer Kapazität von 150 % als Abschaltkriterien eingeführt. Zur Untersuchung der Materialtransformation wurden REM, RFA und XRD postmortem, d.h. nach dem Überladeexperiment eingesetzt. Die operando GC-MS Analyse ergab 80 verschiedene Substanzen, deren Konzentrationsverläufe zeitlich über das Experiment verfolgt wurden. Die Materialstudie zeigte durch das Vorhandensein von Co, Ni und Mn auf der Anodenseite einen stattgefundene Elementmigration, sowie durch die Bilder aus dem REM die Oberflächen der „solid electrolyte interface“ Schicht (SEI).Die gewonnenen Erkenntnisse bezüglich der Materialtransformationen könnten zu einem besseren Verständnis der Wiederverwendbarkeit von Lithiumionenbatterien beitragen, und gleichzeitig die Optimierung von gegebenen Materialien vorantreiben. Die präsentierte Methode der operando GC- MS für schnelle Substanzidentifikation und Konzentrationsmonitoring könnte des Weiteren zur Entwicklung einer standardisierten Analytischen Methode zur Evaluierung der Elektrolyteigenschaften führen. Diese Methode könnte Anwendung in der Überwachung der Umweltauswirkungen, und Sicherheitsrisiken von Batterien finden.Lithium-ion batteries (LIBs) became one of the most ubiquitous energy storage solutions over the past three decades due to their extraordinary properties, such as the high energy density and expanded life over many charge/discharge cycles. However, despite their outstanding properties, material instability and safety have been of concern since the inception of LIBs and continue to be of special interest. Especially electrolyte decomposition through operation of LIBs under non ideal conditions, such as elevated temperatures, moisture rich environments and ungated voltage increase during charging (overcharging), leading to rapid gas evolution and further to fire or explosion is considered a major safety hazard. An investigation of formed gasses and material transformations under these conditions on a molecular level is therefore necessary.For gas analysis, GC-MS presents itself as an excellent analytical tool due to its great capability to separate complex gas mixtures, as well as rapid compound identification and detection during online application. Electron microscopy (SEM), as well as elemental (XRF) and structure analysis (XRD) present viable options for the investigation of material transformation. Operando GC-MS experiments were carried out in EL-Cell (coin size d = 15 mm, built in-house) and pouch cell (provided by Lithops s.r.l (Turin, Italy)) configuration and overcharging was used as a condition for rapid gas formation. In both cases helium was used as a carrier gas to transport the volatiles formed to the GC-MS and the voltage was increased with constant current to twice the cutoff voltage (EL-Cell) or when 60°C or 150 % of the rated capacity (pouch cell) was reached. In the material study, XRF, XRD and SEM were employed postmortem, after overcharging experiments with GC-MS were completed. Operando GC-MS in EL-Cell and pouch cell configuration yielded results of over 80 identified gas species, whose concentration could be semi-quantitatively monitored in 30 min periods. A concentration in the sub percentage range (based on sample mass) of transition metals Mn, Ni, Co from cathode active material could be found on the anode side by XRF, which suggests element migration. SEM images showed layer like depositions, potentially stemming from the SEI.The presented observations of material transformations could contribute to a better understanding of the reusability of LIBs after overcharge but may also support material optimization. The capability of the presented operando GC-MS experimental configurations for fast compound identification and concentration monitoring could lead to the development of a standardized analytical method for electrolyte performance assessment of LIBs. This method then potentially could find application in environmental hazard and safety risk evaluations, as well as in optimizing electrolyte formulation and cell chemistry.10

Identification and characterization of G4-DNA binding proteins from Tetrahymena thermophila

Alternative DNA conformations have been known to exist since before the elucidation of the double helix. The study of alternative DNA conformations formed by telomeric sequences has led to detailed studies of biologically relevant DNA capable of forming unusual structures. In order to understand the biological role of alternative DNA conformations formed by telomeric DNA, proteins which bind these structures have been identified and characterized;The initial portion of my research involved the identification of a protein from Tetrahymena thermophila which binds preferentially to parallel-stranded G-quartet structures. Competition and binding assays demonstrated that the protein, TGP (Tetrahymena G4 binding protein), binds to parallel G-DNA structures but not to antiparallel G-DNA structures or to non-G-DNA duplexes and single stranded oligonucleotides;This initial identification and characterization was followed up by attempts to purify TGP. Cation exchange and Y4-affinity chromatography partially purified two proteins (83 and 50 kDa) that coelute with peak TGP activity. UV cross-linking analysis confirmed the involvement of the 83 kDa protein as a main component of the TGP/G4-DNA complex.</p