Qualitative evaluation of the symptoms and quality of life impacts of long-chain fatty acid oxidation disorders

Background: Long-chain fatty acid oxidation disorders (LC-FAOD) are a group of rare autosomal-recessive genetic disorders characterized by metabolic deficiencies in which the body is unable to convert long-chain fatty acids into energy. To date, however, there is limited understanding of the patient experience of LC-FAOD. Methods: The symptoms, observable signs, and quality of life (QoL) impacts associated with LC-FAOD were explored via a focus group ( n = 8) and semi-structured interviews ( n = 6) with patients and caregivers of patients with LC-FAOD, and interviews ( n = 4) with expert clinicians. Data were analyzed via thematic analysis and summarized in a conceptual model. Results: Participants reported a wide range of signs and symptoms associated with LC-FAOD, broadly categorized as musculoskeletal, endocrine/nutritional/metabolic, neurological, gastrointestinal/digestive, sensory, cardiovascular, respiratory, urological, and constitutional. LC-FAOD were reported to have a significant impact on various aspects of patients’ lives including physical functioning, participation in daily activities, emotional/psychological wellbeing, and social functioning. Lifestyle modifications (such as diet and exercise restrictions) were necessary because of the condition. Symptoms were typically episodic in presentation often arising or exacerbated during catabolic conditions such as prolonged exercise, fasting, physiological stress, and illness/infection. Symptoms were also commonly reported to lead to emergency room visits, hospitalization, and clinical complications. Conclusion: LC-FAOD have a considerable impact on patients’ lives. There is a high degree of concordance in the signs, symptoms, and impacts of LC-FAOD reported by patients, caregivers, and clinicians; however, there were many symptoms and impacts that were only reported by patients and caregivers, thus demonstrating that insights from patient/caregiver experience data are integral for informing medical product development and facilitating patient-centered care.

Chemomicrobiome analysis of the ornithine molecule

Hepatoprotectors and prebiotic molecules that promote the growth of intestinal flora differ significantly in their effects on different representatives of the human microbiome. This work presents the results of a comparative chemomicrobiomic analysis of ornithine and reference molecules (S-ademetionine, ursodeoxycholic acid, lactulose, and fructose). For each of the studied molecules, estimates of the values of the area under the growth curve were obtained for a representative sample of human microbiota, which included 38 commensal bacteria (including bifidobacteria and lactobacilli) and the values of the minimum inhibitory concentrations (MIC) for 152 strains of pathogenic bacteria. It has been shown that ornithine, to a lesser extent than the reference molecules, stimulates the growth of pathogenic bacteria of the genera Aspergillus, Klebsiella, Pseudomonas, Staphylococcus and Candida fungi. Ornithine is also less likely to stimulate the growth of more aggressive bacteria (Biosafety Level 2) and to a greater extent less aggressive bacteria (Biosafety Level 1). By stimulating butyric and other short-chain fatty acid-producing microorganisms, ornithine can improve the profile of gut microbiota.

The Synthesis of Modified Trehalose Glycolipids: Towards Understanding Mincle and MCL Binding

<p>Trehalose glycolipids are a diverse family of long-chain fatty acid diesters isolated from the cell walls of bacteria, in particular Mycobacterium species including M. tuberculosis. These molecules possess an array of biological activities which contribute to the survival and virulence of the organism,however, it is their activity as potent stimulators of innate and early adaptive immunity for which they are of interest. In particular, trehalose glycolipids have an application as adjuvants in vaccines and immunotherapies, for diseases such as tuberculosis (TB) and cancer. Recently, the macrophage-inducible C-type lectin, Mincle, and the macrophage C-type lectin, MCL, were identified as receptors for trehalose glycolipids, however, the exact mechanisms by which these receptors recognise and bind glycolipids is, as yet, unknown.This thesis presents the synthesis of a variety of structurally diverse trehalose glycolipid analogues. As such, three mycolic acids bearing a C22 α-chain and diversified meromycolate branches were prepared from an epoxide intermediate, itself prepared in eight steps from commercially available starting materials. The mycolic acids were then coupled to TMS-trehalose and subsequently deprotected to give the mono-and diester derivatives, 1a-cand 2c, which will be assessed for their immunostimulatory activity through the activation of wild type and Mincle-/-murine macrophages. This work provides a first step towards determining how the structures of trehalose glycolipids influence Mincle and MCL binding and activity, and allow for the development of improved trehalose glycolipids for use in adjuvant therapies.</p>

The Synthesis of Modified Trehalose Glycolipids: Towards Understanding Mincle and MCL Binding

<p>Trehalose glycolipids are a diverse family of long-chain fatty acid diesters isolated from the cell walls of bacteria, in particular Mycobacterium species including M. tuberculosis. These molecules possess an array of biological activities which contribute to the survival and virulence of the organism,however, it is their activity as potent stimulators of innate and early adaptive immunity for which they are of interest. In particular, trehalose glycolipids have an application as adjuvants in vaccines and immunotherapies, for diseases such as tuberculosis (TB) and cancer. Recently, the macrophage-inducible C-type lectin, Mincle, and the macrophage C-type lectin, MCL, were identified as receptors for trehalose glycolipids, however, the exact mechanisms by which these receptors recognise and bind glycolipids is, as yet, unknown.This thesis presents the synthesis of a variety of structurally diverse trehalose glycolipid analogues. As such, three mycolic acids bearing a C22 α-chain and diversified meromycolate branches were prepared from an epoxide intermediate, itself prepared in eight steps from commercially available starting materials. The mycolic acids were then coupled to TMS-trehalose and subsequently deprotected to give the mono-and diester derivatives, 1a-cand 2c, which will be assessed for their immunostimulatory activity through the activation of wild type and Mincle-/-murine macrophages. This work provides a first step towards determining how the structures of trehalose glycolipids influence Mincle and MCL binding and activity, and allow for the development of improved trehalose glycolipids for use in adjuvant therapies.</p>