Radiation damage in macromolecular crystallography: what is it and why should we care?

The basic causes of the radiation damage inflicted on macromolecular crystals during diffraction experiments are summarized, as well as the current state of research which attempts to understand and to mitigate it

Abstracts from the NIHR INVOLVE Conference 2017

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Low vitamin D status is associated with systemic and gastrointestinal inflammation in dogs with a chronic enteropathy

Vitamin D is traditionally known for its role in calcium homeostasis and bone metabolism. However, it has been demonstrated that numerous types of cells express the vitamin D receptor and it is now clear that the physiological roles of vitamin D extend beyond the maintenance of skeletal health. Vitamin D insufficiency, which is typically assessed by measuring the major circulating form of vitamin D, 25 hydroxyvitamin D (25(OH)D), has been associated with a number of disorders in people including hypertension, diabetes, cardiovascular diseases, cancer, autoimmune conditions and infectious diseases. Meta-analyses have demonstrated that serum 25(OH)D concentrations are an important predictor of survival in people with a wide variety of illnesses and have been linked to all-cause mortality in the general human population. The role of vitamin D in non-skeletal disorders in cats and dogs is poorly understood. This is surprising since cats and dogs could act as excellent models for probing the biology of vitamin D. Vitamin D status in people is largely dependent on cutaneous production of vitamin D. This is influenced by many factors such as season, latitude and exposure to ultraviolet (UV) radiation. The interpretation of human studies investigating the effects vitamin D status on disease outcomes are therefore influenced by a number of confounding variables. Unlike humans, domesticated cats and dogs do not produce vitamin D cutaneously and obtain vitamin D only from their diet. The physiological functions and regulation of vitamin D are otherwise similar to humans. Most pets are fed commercial diets containing a relatively standard amount of vitamin D. Consequently, companion animals are attractive model systems in which to examine the relationship vitamin D status and health outcomes. Furthermore, spontaneously occurring model systems which did not require disease to be induced in healthy animals would allow the numbers of animals used in scientist research to be reduced. This thesis aimed to define vitamin D homeostasis in companion animals in three disease settings; in cats with feline immunodeficiency virus (FIV) infection, dogs with chronic enteropathies (CE) and in hospitalised ill cats. Additional aims were to assess the prognostic significance of serum 25(OH)D concentrations in companion animals and the relationship between serum 25(OH)D concentrations and markers of inflammation. The hypothesis of this thesis was that vitamin status D would negatively correlate with presence of disease, markers of inflammation and disease outcomes. As similar findings have been demonstrated in human medicine, the hypothesis was that cats and dogs would be suitable models to investigate the role of vitamin D in human disease. This thesis demonstrates that in dogs with a CE serum 25(OH)D concentrations are negatively correlated with inflammation and are predictive of clinical outcomes. Vitamin D status was also lower in cats with FIV and importantly vitamin D status was predictive of short term mortality in hospitalised ill cats. This research will be of interest to veterinary surgeons and opens the possibility for clinical trials which examine if low vitamin D status is causally associated with ill health and whether vitamin D supplementation results in superior treatment outcomes in companion animals. This thesis also demonstrates the potential of cats and dogs as model systems in which to examine the role of vitamin D in human health

Arabidopsis thaliana as a model for host plant- herbivore- natural enemy interactions

EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Current Delivery of Infant Mental Health Services: Are Infant Mental Health Needs Being Met?

Objective: To identify services supporting the well-being of infants and their families in an area of South Brisbane, Australia, highlight problems of accessing these services and recommend strategies to make them more readily available. Method: Semistructured interviews were conducted with staff from 18 service providers offering antenatal services, or programmes primarily focused on children under the age of 2 years and/or their families. The interview aimed to identify the precise nature of the services offered, problems encountered in providing those services, perceived gaps in services and potential strategies for improvement. Results: Services were diverse, provided by a range of different professionals, in varying locations (home, community, hospital) and with funding from various sources. The major findings were: (i) the fragmentation of services, lack of communication between them, and lack of continuity in services from one stage of family formation to another; (ii) the shortage of services working with the parents and infant together; and (iii) the difficulty of providing services for some at-risk populations. Conclusions: Recommendations included: (i) maintaining a range of different services networked through a centralized resource/referral centre; (ii) expanding joint mother–infant services and providing training for such services; and (iii) supporting outreach services for difficult to engage populations

Simultaneous X-ray diffraction from multiple single crystals of macromolecules

The potential in macromolecular crystallography for using multiple crystals to collect X-ray diffraction data simultaneously from assemblies of up to seven crystals is explored. The basic features of the algorithms used to extract data and their practical implementation are described. The procedure could be useful both in relation to diffraction data obtained from intergrown crystals and to alleviate the problem of rapid diffraction decay arising from the effects of radiation damage