Aspergillus flavus infections in Galleria mellonella : a pathogen-host model system for the study of emerging diseases

To study emerging diseases, I employed a model pathogen-host system involving infections of insect larvae with the opportunistic fungus Aspergillus flavus, providing insight into three mechanisms ofpathogen evolution namely de novo mutation, genome decay, and virulence factoracquisition In Chapter 2 as a foundational experiment, A. flavus was serially propagated through insects to study the evolution of an opportunistic pathogen during repeated exposure to a single host. While A. flavus displayed de novo phenotypic alterations, namely decreased saprobic capacity, analysis of genotypic variation in Chapter 3 signified a host-imposed bottleneck on the pathogen population, emphasizing the host's role in shaping pathogen population structure. Described in Chapter 4, the serial passage scheme enabled the isolation of an A. flavus cysteine/methionine auxotroph with characteristics reminiscent of an obligate insect pathogen, suggesting that lost biosynthetic capacity may restrict host range based on nutrient availability and provide selection pressure for further evolution. As outlined in Chapter 6, cysteine/methionine auxotrophy had the pleiotrophic effect of increasing virulence factor production, affording the slow-growing auxotroph with a modified pathogenic strategy such that virulence was not reduced. Moreover in Chapter 7, transformation with a virulence factor from a facultative insect pathogen failed to increase virulence, demonstrating the necessity of an appropriate genetic background for virulence factor acquisition to instigate pathogen evolution.

Photograph of Charles Bell with Horse and Cart, St. Catharines [n.d.]

Charles Bell is pictured in this black and white undated photograph with his horse and cart. Mr. Bell ran an ice and coal business on Geneva St. in St. Catharines, Ontario. This photograph was in the possession of the Rick Bell family, of St. Catharines.Handwritten inscription on the reverse reads: "Grandpa Charles Bell ran ice and coal business, Geneva St. St. Catharines"

A research capacity strengthening project for infectious diseases in Honduras: experience and lessons learned

Background: In Honduras, research capacity strengthening (RCS) has not received sufficient attention, but an increase in research competencies would enable local scientists to advance knowledge and contribute to national priorities, including the Millennium Development Goals (MDGs). Objective: This project aimed at strengthening research capacity in infectious diseases in Honduras, focusing on the School of Microbiology of the National Autonomous University of Honduras (UNAH). The primary objective was the creation of a research-based graduate program for the continued training of researchers. Parallel objectives included institutional strengthening and the facilitation of partnerships and networks. Methods: Based on a multi-stakeholder consultation, an RCS workplan was designed and undertaken from 2007 to 2012. Due to unexpected adverse circumstances, the first 2 years were heavily dedicated to implementing the project's flagship, an MSc program in infectious and zoonotic diseases (MEIZ). In addition, infrastructure improvements and demand-driven continuing education opportunities were facilitated; biosafety and research ethics knowledge and practices were enhanced, and networks fostering collaborative work were created or expanded. Results: The project coincided with the peak of UNAH's radical administrative reform and an unprecedented constitutional crisis. Challenges notwithstanding, in September 2009, MEIZ admitted the first cohort of students, all of whom undertook MDG-related projects graduating successfully by 2012. Importantly, MEIZ has been helpful in expanding the School of Microbiology's traditional etiology-based, disciplinary model to infectious disease teaching and research. By fulfilling its objectives, the project contributed to a stronger research culture upholding safety and ethical values at the university. Conclusions: The resources and strategic vision afforded by the project enhanced UNAH's overall research capacity and its potential contribution to the MDGs. Furthermore, increased research activity and the ensuing improvement in performance indicators at the prime Honduran research institution invoke the need for a national research system in Honduras.

Diagram of a Horse

A diagram of a horse, labelled and illustrated by Dorothy Rungeling.

Photograph - Hamilton Killaly Woodruff with a Child on Rocking Horse

Black and white photograph, 16 cm x 11 ½ cm, of Hamilton Killaly Woodruff with a young child [Charles Woodruff Band?]. The child is sitting on a rocking horse and Hamilton is standing watching the child with his hat in one hand and his cane in the other.

The Horse Shoe Fall

The description on the reverse states "The Majesty and Beauty of Niagara. The Horse Shoe Fall." There is also a No. associated with the card, but the original printed number (5800_01) has been crossed out and replaced in ink with 5795.

List of prices paid to Dilly Coleman by Doctor Richard .S. King for the board and feeding of a horse

List (2 pages, handwritten) of prices paid to Dilly Coleman by Doctor Richard .S. King for the board and feeding of a horse. There is a handwritten note on the inner page regarding instructions for feeding the horse, Sept. 1850.

Voucher from the Engineer Department of Port Dalhousie and Thorold Railway Extension to W.G. Thompson regarding horse hire (copy), Jul. 30, 1857

Voucher from the Engineer Department of Port Dalhousie and Thorold Railway Extension to W.G. Thompson regarding horse hire (copy), Jul. 30, 1857.