Mistake by Noah

It might have changed history -- but it didn\u27t. Noah was happy. A home-loving body was Noah, content with his lot. He had his wife, and he had his pigs. He had his garden an a house full of in-laws

A proteomic investigation of the rhizomes of the resurrection fern Mohria caffrorum L. (Desv.) in response to desiccation

Includes bibliographical referencesAs there is limited information on the mechanisms of vegetative desiccation-tolerance in resurrection plant rhizomes, this work was undertaken to study the mechanisms of desiccation-tolerance in Mohria caffrorum rhizomes. Fronds of this plant have been previously characterized as being desiccation-tolerant in summer and desiccation-sensitive in winter. Since fern rhizomes are perennial organs, it was of interest to establish whether these organs are also perennially desiccation-tolerant and, whether or not the rhizomes regulate desiccation-tolerance in the fronds. Ultra-structural evidence using transmission electron microscopy and viability studies using electrolyte leakage analysis showed that the rhizomes were desiccation-tolerant throughout the seasons. Quantitative proteomics analysis using isobaric tags for relative and absolute quantification was employed to investigate molecular mechanisms of desiccation-tolerance in the rhizomes of this plant. Using a custom fern rhizome specific peptide sequence database, 236 proteins were identified. Of these, 16 proteins increased in abundance while 14 declined, in the summer collected rhizomes. On the other hand, 16 proteins increased in abundance and 20 declined in the winter form. Western blot analysis confirmed the expression trends of heat shock protein 70-2 and superoxide dismutase-[Cu-Zn], which were among the differentially expressed proteins. Bioinformatics analysis of the differentially expressed proteins was carried out using network enrichment tools, to identify key molecular processes and pathways involved in the rhizome response to desiccation stress. Results indicate that the rhizomes use different molecular mechanisms to achieve desiccation-tolerance in winter and summer. Potential cross-talks and cross-tolerances were identified in which mechanisms protecting the rhizomes against desiccation-tolerance appeared to also protect them against heat stress, and in winter an apparent cross-talk against desiccation and pathogen stresses was also identified. This study is the first report of evidence that M.caffrorum rhizomes are the 'master-regulator organs' responsible for regulating desiccation-tolerance in the fronds. This role was inferred from the rhizome's predicted up-/down-regulation of biological processes and pathways that relate to leaf senescence, shoot system morphogenesis and gametophyte development, among others

Resale Price Maintenance and Consumer Welfare

Vertikala restriktioner och särskilt sådana gällande pris har i allmänhet ansetts ha negativa effekter på konkurrens under en lång tid, både i USA och i EU. Prisgolv har en lång historia av att ses som konkurrensbegränsande. I USA har det setts som per se olagligt i nästan hundra år under Sherman Act avsnitt 2. Under de senaste decennierna har det dock skett en förändring i synen på prisgolv, som börjar med att framstående ekonomer argumenterade att olagligheten var grundlös. Denna utveckling startade på 60-talet, med Chicagoskolan som förtrupp för denna kampanj. Det har varit en pågående utveckling som kulminerade i fallet Leegin där högsta domstolen ersatte per se olagligheten den med en tillämpning av Rule of Reason doktrinen. Inom EU har det skett en liknande utveckling. Detta har emellertid inte lett till ett liknande resultat. Prisgolv, som en vertikal restriktion har alltid setts som konkurrensbegränsande och även nu efter utvecklingen i USA och en liknande förändring åt att se mer positivt på vertikala restriktioner så finns fortfarande en stark presumtion om illegalitet gällande prisgolv. Denna uppsats undersöker sambandet mellan prisgolv och konsumenternas välfärd. Avhandlingen visar konsumenternas välfärd har en stark plats i bedömningen inom konkurrensrätten. Även om den inte har den status som den har i den amerikanska konkurrensrätten, så är den fortfarande mycket närvarande, särskilt på en praktisk nivå. Avhandlingen fortsätter att undersöka olika ekonomiska teorier om effekterna av prosgolv och tydligt visar en tvetydighet när det gäller dessa. I brist på empiriska bevis och teoretiskt stöd för en allmän presumtion om olaglighet mot prisgolv så finner denna avhandling att en lämplig metod skulle vara ett borttagande av statusen som en allvarlig restriktion och nämnda presumtion. Istället skall man röra sig mot en tillämpning av den Amerikanska Rule of Reason doktrinen genom en renare tillämpning av Artikel 101(3) TFEU.Vertical restrictions and especially price restriction has generally been deemed anticompetitive during the years, both in the US as well as in the EU. Minimum resale price maintenance has a long history of being seen as anti-competitive. In the USA there has been a per se illegality regarding RPM for almost a hundred years under the Sherman Act section 2. However, in the last decades there has been a change in the attitude towards RPM, starting with prominent economists arguing that the per se illegality was without grounds. This development started in the 60s, with the Chicago School as the vanguard for this crusade. It has been an ongoing development which culminated in the removal of the per se illegality in Leegin, where the Supreme Court substituted it with the Rule of Reason. In the European Union there has been a similar development. This however has not lead to a similar result. RPM, as a vertical restraint has always been seen as anticompetitive and even now after the development in the USA and a similar loosening of the snare around vertical restraint in the EU there is a quite harsh presumption of illegality. This thesis investigates the relationship between resale price maintenance (RPM) and consumer welfare. The thesis shows that there is a solid role for consumer welfare within competition law. While it does not have the status that it has in the US antitrust system but is still very present, especially at a practical level. The thesis continues to investigate different economic theories regarding the effects of minimum RPM and clearly shows an ambiguity regarding the theoretical effects. In lack of empirical evidence as well as theoretical support for a general presumption of illegality towards RPM this thesis concludes that the appropriate approach would be a removal of the status as a hard core restriction and said presumption and by moving towards the US Rule of Reason approach through a pure application of Article 101(3)

Stiffness and Modulus and Independent Controllers of Breast Cancer Metastasis

One out of eight women in the United States will develop breast cancer during their lifetime. Ninety percent of cancer related deaths are due to metastasis. Metastasis is the biological process where individual or aggregate cancerous cells break away from the primary tumor site and colonize distant, non-adjacent locations throughout the body. It is my objectives to study how mechanical, topographical and biochemical cues affect metastatic breast cancer metastasis at an early developmental stage. ECM components have previously been shown to affect cell motility via ligand-receptor interactions, and physical cues, such as matrix stiffness and protein density. The primary tumor site significantly stiffens during tumor progression. The ability cells have to sense and respond to these matrix features influences and facilitates cell invasion. It is now widely accepted that mechanical properties of the ECM can regulate cell migration; however, presently, tissue modulus and stiffness have been used interchangeably. It is unknown if cell responses are sensitive to a bulk tissue modulus or stiffness on the geometric length scale of the cell. It is my objective to create tunable biomaterials from known materials to independently parse the roles of stiffness and modulus upon the migration of breast cancer cells. I have created a variety of tunable biomaterials which I can parse the roles of mechanical properties and observe their affect upon cell mechanosensing. All systems were coated with collagen I, which is the most abundant ECM protein during tumor development. I was able to quantify the migration along with other parameters of the metastatic breast cancer cell line MDA-MB-231. My results show that the highly metastatic MDA-MB-231 is stiffness sensitive among all biomaterial models. Cells maximum cell speeds are at high concentrations of collagen I on the polymer microlenses and show a biphasic response dependent on stiffness. On poly (ethylene glycol)- 2-Methacryloyloxyethyl phosphorylcholine (PEG-PC) hydrogels cells favor intermediate modulus and show stiffness dependency at low protein concentrations. Cells on Cd/Se and polydimethylsiloxane (PDMS) samples are influenced by the topographical cue more so than the stiffness or modulus of the material. By controlling mechanosensing via force transduction signaling pathways, and determining the appropriate length-scale by which mechanical properties regulate cancer metastasis, I hope to eventually uncover novel therapeutics to block cell invasion

Sex differences in the relationship between white matter connectivity and creativity

Creative cognition emerges from a complex network of interacting brain regions. This study investigated the relationship between the structural organization of the human brain and aspects of creative cognition quantified by divergent thinking tasks. Diffusion weighted imaging (DWI) was used to obtain fiber tracts from 83 segmented cortical regions. This information was represented as a network and metrics of connectivity organization, including connectivity strength, clustering and efficiency were computed, and their relationship to personal levels of creativity was examined. Permutation testing identified significant sex differences in the relationship between global connectivity and creativity as measured by divergent thinking tests. Females demonstrated significant inverse relationships between global connectivity and creative cognition; there were no significant relationships observed in males. Node specific analyses found inverse relationships across measures of Connectivity, Efficiency, Clustering and creative cognition in widespread regions in females. Our findings suggest that females involve more regions of the brain in processing to produce novel ideas to solutions, perhaps at the expense of efficiency (greater path lengths). Males, in contrast, exhibited few, relatively weak positive relationships across these measures. Extending recent observations of sex differences in connectome structure, our findings of sexually dimorphic relationships suggest a unique topological organization of connectivity underlying the generation of novel ideas in males and females

The Development of Methods to Account for Physiologic Dynamic Changes and Their Effects on the Pharmacokinetics of Therapeutic Monoclonal Antibodies and other Therapeutics

Physiologic changes in the body can drastically affect the clearance of a medication, and therefore increase the variability in exposure to the medication. Physiologic changes that can have a profound effect on the exposure of a medication can stem from changes CYP enzymes, transport proteins, binding protein expression, organ function, immune reactivity, and health status to name a few; with the focus of this dissertation on the dynamic changes in the ontogeny of MRP2 (an apical liver transport protein) and the dynamic changes caused by an immune response to a therapeutic monoclonal antibody (mAb). Several approaches can be used to limit or capture the changes in the pharmacokinetics of a medication caused by ontogeny and immune reactivity related dynamic changes. Three approaches were investigated in this dissertation: 1) preventing/limiting immunogenicity’s effect on a therapeutic mAb, hence eliminating the increase in clearance and variability, 2) using a pharmacometric PK-ADA modeling approach to model immunology-related dynamic and variable effects on a therapeutic mAb and 3) using a systems pharmacology strategy to model the ontogeny changes in a transport protein (MRP2) and the dynamic effects on its drug substrates. In the preclinical and clinical setting, anti-drug antibodies (ADA) that develop against therapeutic mAbs can influence patient safety and interfere with product efficacy. Thus, my first focus in this dissertation investigates methods to limit/prevent immunogenicity and therefore help to eliminate a source of variability and clearance that can be seen in preclinical and clinical studies. My first study investigates the use of immune suppressants in mitigating ADA responses to a fully-humanized mAb in preclinical animal studies. Three groups of Sprague Dawley rats (n=18) were treated with low (0.01 mg/kg), moderate (50 mg/kg), or high (300 mg/kg) doses of a mAb. Experimental groups also received either methotrexate or tacrolimus/sirolimus immune suppression. Methotrexate significantly lowered the incidence of anti-variable region antibodies at moderate mAb dose (P\u3c0.05), while tacrolimus/sirolimus did likewise at moderate and high doses (P\u3c0.01) of mAb. With the exception of low dose mAb plus methotrexate, all immunosuppressed groups displayed more than a 70-fold decrease in ADA magnitude (P\u3c0.05). This abrogation in ADA response correlated with higher mAb exposure in the circulation by week 4 for the moderate and high dosed mAb groups. This method provides an approach to mitigate preclinical immunogenicity by the use of immunosuppressant modalities. Such preconditioning can support preclinical drug development of human therapeutics that are antigenic to animals but not necessarily to humans. Similar approaches to reduce immunogenicity will likely play an essential role with advances in novel therapeutics like fully human mAbs, recombinant proteins, fusion proteins as well as bispecific- and drug-conjugated antibodies. In some cases there may not be a method to reduce/eliminate immunogenicity and the dynamic changes in the elimination of a therapeutic mAb that result. In a preclinical setting, ADA typically influences both multiple dose toxicity studies, as well as preliminary pharmacokinetic (PK) analysis by leading to an increase in clearance of the therapeutic mAb. This increase in clearance caused by ADA can be highly variable due to each animal’s polyclonal immune response to a therapeutic mAb. My second focus aims to account for ADA and its variable effect on a fully human therapeutic mAb. I used data acquired from our previous study that investigated the use of immunosuppressant therapy in mitigating ADA responses to a mAb in a preclinical Sprague Dawley rat study and incorporated much of the data from that study, which included three mAb dosing groups and three immunomodulation therapies. A pharmacometric PK-ADA modeling approach was used to analyze the data. Our model was able to simultaneously capture the pharmacokinetics of the mAb in the presence and absence of ADA, accounting for an immune reaction’s highly variable effect on a therapeutic mAb concentration-time profile. The pharmacometric PK-ADA methodology used in this study demonstrates a modeling strategy that can be applied to other therapeutic mAbs to assess the immunogenicity of a therapeutic mAb and the dynamic effect immunogenicity has on the pharmacokinetics. This modeling methodology can further be applied to the simulation of therapeutic mAbs in the presence of varying rates, magnitudes and affinities of ADA reactions, aiding in the development of appropriately powered toxicology studies and an accurate pharmacokinetic evaluation of a human therapeutic mAb in a preclinical setting. Transport proteins play an important role in determining the disposition of medications in the human body. The expression of transport proteins in the body is not constant throughout childhood development, which affects the pharmacokinetics of a medication that is a substrate of the transport protein. Multidrug resistance protein 2 (MRP2) represents a major hepatic transporter whose expression is dynamic throughout development. MRP2 plays a vital role in the biliary excretion of various organic anions and cations along with glutathione-, glucuronate-, or sulfate-conjugates of several drug substrates. Our third aim is to evaluate the effect the ontogeny of MRP2 has on the pharmacokinetics of ceftriaxone to better understand how a transport protein contributes to the disposition of its substrates throughout childhood development. In order to accomplish our aim, a systems pharmacology modeling approach was used to understand MRP2’s contribution to the elimination of ceftriaxone and the effect of ontogeny changes on the pharmacokinetics of ceftriaxone in pediatric patients. Data from ex vivo studies, preclinical in vivo studies and clinical studies were used to inform our model. Results from the study demonstrate the contribution of MRP2 to the pharmacokinetics of ceftriaxone. Our model was able to capture ceftriaxone’s pharmacokinetics, and MRP2’s contribution to its clearance, allowing for the prediction of pediatric ceftriaxone concentrations. This modeling strategy can also be used to evaluate ontogeny changes in other biochemical transposition proteins, and the subsequent effect on the pharmacokinetics of other therapeutically used compounds. In summary, our work has successfully provided approaches to limit/prevent dynamic changes caused by immune reactions to a therapeutic mAb, demonstrate a pharmacometric PK-ADA approach that can capture the PK changes and variability caused by ADA formation on a therapeutic mAb and demonstrate a systems pharmacology model approach which accounts for the ontogeny of a transport protein and the resultant PK effects on its substrate through childhood development. The following chapters describe and discuss these novel approaches

The resource-based and relational views: complementary perspectives of competitive advantage

Two theoretical perspectives that recognize that differences in firm performance are due to differences in resource endowments are the Resource-based View (RBV) (Barney, 1991) and the Relational View (Dyer & Singh, 1998). However, while the RBV focuses on the attributes of resources endowments that reside within the firm, the Relational View asserts that a firm\u27s critical resources can reside outside the firm. The purpose of this research is to examine the Relational View and the Resource-based View as complementary perspectives by exploring the question: Does the Relational View contribute additional and positive explanatory power to a Resource-based View of competitive advantage? This study offered a conceptual model of competitive position as comprised of a firm\u27s intraorganizational resource position (the Resource-based View) as well as a firm\u27s interorganizational resource position (the Relational View). To test the hypotheses developed from this model, data was gathered from reliable primary and secondary sources relating to resource endowments, integration strategy and organizational performance. This data was gathered for hospitals (853 hospitals) in 33 of the largest Metropolitan Statistical Areas (MSAs). Results obtained using regression indicated that the strength of both firms\u27 intraorganizational resource positions as well as their interorganizational resource positions is positively related to performance. Performance was measured with four variables. Return on Assets, Cash Flow Margin, Growth and Market Share. This provided support for the notion that the Relational View provides a needed complementary perspective to the RBV of competitive advantage. Finally, the study\u27s non-findings indicated that while strategic complementarity was positively related to performance, organizational complementarity did not have the hypothesized moderating effect on the relationship between interorganizational resource position and performance