Triple Helix, Fall 2018

Table of Contents: Science Agenda: The Politics of Grant Writing / by Kavya Rajesh (p. 4) -- From the Experts / by Katherine Bruner (p. 5) -- 3D Printed Drugs: The Future of Pharmaceuticals / by Ethan Wang (p. 6) -- Computerized Markets: Wall Street Takeover / by James Kiraly (p. 10) -- The Evolution of Fear / by Alisha Ahmed (p. 14) -- ADDing Up / by Victor Liaw (p. 18) -- The Clone Wars / by Jina Zhou (p. 22) -- Physician-Assisted Suicide: Drawing the Line / by Haley Wolf (p. 26) -- Supervised Injection Sites / by Alex Gajewski (p. 30) -- On Emerging Medicalization and Health Care / by Patrick Lee (p. 33) -- The Future of Human Gene Modifications / by Elizabeth Robinson (p. 36)College of Natural SciencesUT LibrariesLiberal Art

Biomatériaux dérivés d’une matrice extracellulaire (MEC) pour l’ingénierie tissulaire et les dispositifs médicaux

Abstract: Tissue engineering involves the production of whole organ or a part of it in vitro or in vivo. Decellularized organs as scaffolds for reconstructing organs have been emerging due to the potential of the ExtraCellular Matrix (ECM). ECM is a complex structure primarily composed of proteins and glycosaminoglycans (GAGs). Most common proteins include collagens, laminins, fibronectins and elastins. Several commercial products have been derived from ECM including tissue papers, 3D-printed scaffolds, and wound dressings. Bioadhesives are currently employed alone or as adjuncts to sutures to seal leaks of air or blood from organs following surgical interventions. ECM-incorporated bioadhesives could be hypothesized to not only seal leaks, but also to regenerate tissues. This thesis aims to investigate the composition and properties of ECMs derived from different porcine organs (bladders, kidneys, livers, lungs, and pancreas) using detergent-based and detergent-free methods. The first experimental work includes the design of a cell culture system to study the effect of detergent-based and detergent-free decellularized bladders on insulin-secreting rat pancreatic cell (INS-1) proliferation and functionality. ECMs were characterized initially for conservation of ultrastructure and removal of dsDNA. CyQUANT proliferation assay indicated cell proliferation following 7 days of culture on detergent-free decellularized bladders. Glucose-stimulated insulin secretion (GSIS) and immunostaining confirmed that cells were functional. The second experimental work involved decellularization of the five porcine organs using the detergent-based and detergent-free methods. Two additional steps were added to the detergent-free approach (pH adjustment and ethylenediaminetetraacetic acid (EDTA) treatment) to aid in the removal of residual hemoglobin from the organs. ECMs were characterized by staining for the removal of cellular content and conservation of ultrastructure. Further, mass spectrometry revealed better conservation of a greater number of key proteins such as collagen IV, laminins, fibronectin, and elastin in the ECM resulting from the detergent-free methods, as compared to that produced using the detergent-based one. Collagen fibers orientation measurement indicated preservation of the fibers orientation in the ECMs as compared to that measured in the native organs. The third experimental work initially screened the INS-1 cell response on different organ ECMs. INS-1 cells were functional on certain detergent-free decellularized organs following 7 days of cell culture. Finally, mouse primary pancreatic islets were seeded on the detergent-free decellularized bladders, revealing functional islets following 48 hours of culture.Le génie tissulaire consiste à construire un organe entier ou une partie de celui-ci in vitro ou in vivo. Les organes décellularisés utilisés comme échafaudages pour la reconstruction d'organes sont de plus en plus populaires en raison, entre autres, du potentiel de la matrice extracellulaire (MEC). La MEC consiste en un ensemble complexe composé principalement de protéines et de glycosaminoglycanes (GAG). Les protéines les plus courantes comprennent les collagènes, les laminines, les fibronectines et l’élastine. Plusieurs produits commerciaux sont composés de MEC, notamment des papiers tissulaires, des encres pour l’impression 3D et des pansements pour le traitement de plaies. Les bio-adhésifs sont actuellement utilisés seuls ou en complément des sutures pour sceller les fuites d'air ou de sang à la suite d’interventions chirurgicales. On pourrait supposer, par exemple, qu’un bio-adhésif incorporant la MEC permettrait non seulement de sceller une fuite, mais qu'il contribuerait également à la régénération tissulaire. Cette thèse a pour objectif général d’évaluer la composition et les propriétés de la MEC dérivée de différents organes porcins (vessie, rein, foie, poumon et pancréas) décellularisés à l'aide de méthodes utilisant un détergent et sans détergent. Également, le projet vise à développer une nouvelle famille de biomatériaux à base de MEC pour des applications en médecine. Le premier travail expérimental comprend la conception d'un système de culture cellulaire pour étudier l'effet des vessies décellularisées, avec ou sans détergent, sur la prolifération et la fonctionnalité des cellules pancréatiques (INS-1 cellules) de rat sécrétant de l'insuline en réponse à des gradients de glucose. Les MECs ont été initialement caractérisées pour la conservation de l'ultrastructure et l'élimination de l'ADN double brin. L'analyse utilisant un test de prolifération CyQUANT a indiqué une prolifération cellulaire après 7 jours de culture sur les vessies décellularisées sans détergent. La sécrétion d'insuline stimulée par le glucose (GSIS) et l'immunomarquage ont confirmé que les cellules étaient également fonctionnelles. Le deuxième travail expérimental visait la décellularisation des cinq organes porcins à l'aide d’une méthode utilisant un détergent et de méthodes sans détergent. Deux étapes supplémentaires ont été ajoutées à la technique sans détergent (ajustement du pH et traitement par éthylènediaminetétraacétate (EDTA)) afin de réduire la présence d'hémoglobine résiduelle dans les organes décellularisés. Les MECs ont été caractérisées en histologie par différentes colorations pour investiguer l'élimination du contenu cellulaire et la conservation de l'ultrastructure. De plus, la spectrométrie de masse a révélé la conservation d'un plus grand nombre de protéines clés telles que le collagène IV, les laminines, la fibronectine et l'élastine dans les MECs produites avec des méthodes sans détergent par rapport à celles résultantes de la méthode utilisant un détergent. Les mesures de l’orientation du collagène ont indiqué une conservation de l'orientation dans les MECs par rapport à la structure native. Le troisième travail expérimental a initialement investigué la réponse des cellules INS-1 exposées aux différentes MEC d'organes. Les cellules INS-1 demeuraient fonctionnelles sur certains organes décellularisés sans détergent après 7 jours de culture. Enfin, des îlots pancréatiques primaires de souris ont été ensemencés sur des vessies décellularisées sans détergent, révélant ainsi que les îlots étaient fonctionnels après 48 heures de culture

Measurement and reduction of the environmental impact of industrial photochemical machining

This thesis concerns research into the environmental aspects of the photochemical machining (PCM) industry, involving measurement, analysis, benchmarking, and reducing adverse environmental impacts. The environmental audit of a PCM company found that the likely significant environmental impacts are the use of ferric chloride etchant, solvents and water. A comparison of the environmental performance of two UK PCM companies showed that there were big contrasts in etchant utilisation and solvent and water consumption, indicating that steps could be taken to reduce these impacts. A study to assess the feasibility of using laser direct imaging (LDI), a cleaner technology in photoresist imaging, found that LDI could meet the technical requirements of the PCM industry. For LDI to be economically feasible, the reliability has to be high and maintenance cost has to be low. Audit surveys of PCM companies world-wide regarding etchant utilisation and solvent consumption indicated that: (1) There is a vast difference between the performance of companies and companies that regenerate etchants were more efficient in their FeCl3 utilisation. The industrial best practice for FeCl3 utilisation is 837%. (2) Chlorination was the most popular regeneration method but most companies would use a more environment-friendly system at a higher overall cost. Regarding waste disposal, most companies sent liquid waste etchant for reclaim or recycle. (3) Half of the PCM companies no longer use solvents, and with the development of liquid aqueous-based resists, it is envisaged that PCM practitioners could eliminate the use of solvents in the near future. Lastly, an investigation into the feasibility of using oxygen gas in regenerating FeCI3 showed that the regenerated etchant could produce good quality etchings. This syst'm is also the second cheapest. Therefore, it is a good option for the PCM companies as the cost of regeneration is not too expensive and it is environment-friendly

Rapid culture-based methods for drug-resistance detection in Mycobacterium tuberculosis.

Tuberculosis still represents a major public health problem, especially in low-resource countries where the burden of the disease is more important. Multidrug-resistant and extensively drug drug-resistant tuberculosis constitute serious problems for the efficient control of the disease stressing the need to investigate resistance to first- and second-line drugs. Conventional methods for detecting drug-resistance in Mycobacterium tuberculosis are slow and cumbersome. The most commonly used proportion method on Löwenstein-Jensen medium or Middlebrook agar requires a minimum of 3-4 weeks to produce results. Several new approaches have been proposed in the last years for the rapid and timely detection of drug-resistance in tuberculosis. This review will address phenotypic culture-based methods for rapid drug susceptibility testing in M. tuberculosis

Effect of storage time on microbial quality of some spices and dried seasonings

The effect of storage time on the microbial quality of some spices and dried seasonings (SDS) (dawadawa, pepper, ginger, shrimp and fish powders) was studied over a 12-month period. Microbial load and profile of irradiated and unirradiated SDS were assessed at 0, 6 and 12-month periods. The range of total variable counts (TVCs) were initially determined at 0.81-4.53 and 4.65-8.51 log10 cfu g-1 for irradiated and unirradiated SDS, respectively; those for mould and yeast counts (MYCs) were determined at 0-1.74 and 1.55-3.35 log10 cfu g-1, respectively. Generally, TVCs were not significantly affected (

Neisseria gonorrhoeae Coinfection during Chlamydia muridarum Genital Latency Does Not Modulate Murine Vaginal Bacterial Shedding

Chlamydia trachomatis and Neisseria gonorrhoeae are the most frequently reported agents of bacterial sexually transmitted disease worldwide. Nonetheless, C. trachomatis/N. gonorrhoeae coinfection remains understudied. C. trachomatis/N. gonorrhoeae coinfections are more common than expected by chance, suggesting C. trachomatis/N. gonorrhoeae interaction, and N. gonorrhoeae infection may reactivate genital chlamydial shedding in women with latent (quiescent) chlamydial infection. We hypothesized that N. gonorrhoeae would reactivate latent genital Chlamydia muridarum infection in mice. Two groups of C. muridarum-infected mice were allowed to transition into genital latency. One group was then vaginally inoculated with N. gonorrhoeae; a third group received N. gonorrhoeae alone. C. muridarum and N. gonorrhoeae vaginal shedding was measured over time in the coinfected and singly infected groups. Viable C. muridarum was absent from vaginal swabs but detected in rectal swabs, confirming C. muridarum genital latency and consistent with the intestinal tract as a C. muridarum reservoir. C. muridarum inclusions were observed in large intestinal, but not genital, tissues during latency. Oviduct dilation was associated with C. muridarum infection, as expected. Contradicting our hypothesis, N. gonorrhoeae coinfection did not reactivate latent C. muridarum vaginal shedding. In addition, latent C. muridarum infection did not modulate recovery of vaginal viable N. gonorrhoeae. Evidence for N. gonorrhoeae-dependent increased C. muridarum infectivity has thus not been demonstrated in murine coinfection, and the ability of C. muridarum coinfection to potentiate N. gonorrhoeae infectivity may depend on actively replicating vaginal C. muridarum. The proportion of mice with increased vaginal neutrophils (PMNs) was higher in N. gonorrhoeae-infected than in C. muridarum-infected mice, as expected, while that of C. muridarum/N. gonorrhoeae-coinfected mice was intermediate to the singly infected groups, suggesting latent C. muridarum murine infection may limit PMN response to subsequent N. gonorrhoeae infection. IMPORTANCE Our work builds upon the limited understanding of C. muridarum/N. gonorrhoeae coinfection. Previously, N. gonorrhoeae infection of mice with acute (actively replicating) vaginal C. muridarum infection was shown to increase recovery of viable vaginal N. gonorrhoeae and vaginal PMNs, with no effect on C. muridarum vaginal shedding (R. A. Vonck et al., Infect Immun 79:1566-1577, 2011). It has also been shown that chlamydial infection of human and murine PMNs prevents normal PMN responses, including the response to N. gonorrhoeae (K. Rajeeve et al., Nat Microbiol 3:824-835, 2018). Our findings show no effect of latent genital C. muridarum infection on the recovery of viable N. gonorrhoeae, in contrast to the previously reported effect of acute C. muridarum infection, and suggesting that acute versus latent C. muridarum infection may have distinct effects on PMN function in mice. Together, these studies to date provide evidence that Chlamydia/N. gonorrhoeae synergistic interactions may depend on the presence of replicating Chlamydia in the genital tract, while chlamydial effects on vaginal PMNs may extend beyond acute infection

The U.S. M-Business Market: Fad or the future

M-Business is information available on any device, anywhere and at anytime, offering businesses in any industry the potential to expand markets, improve their services and reduce costs. The U.S. m-business market is still in its infancy and is a few years away from becoming a growth market. This is due to a few reasons, which are the lack of standards for connectivity and service, no real applications to support the market and the lack of strong encryption to support m-business and e-commerce. M-business is not a fad but a potential new channel for business operations. This thesis will address the issues of why the U.S. m-business is slow to mature and what is required for the U.S. m-business to become a growth market