The role, the risk, and the reciprocity: creating positive early rural placements in medical education.

Introduction: The Northern Ontario School of Medicine University seeks to address rural physician shortages in Northern Ontario. One key strategy the school employs is the use of experiential learning placements embedded throughout its undergraduate curriculum. In second year, students embark on two 4-week placements in rural and remote communities.

A Qualitative Investigation of the Experiences of Students and Preceptors Taking Part in Remote and Rural Community Experiential Placements During Early Medical Training.

Background: Medical education can help alleviate the chronic undersupply of physicians to rural communities. Providing students with early rural clinical experiences may allow the gaining of necessary knowledge and skills to practice and live rurally, as well as the desire to do so.

Purpose: This study aims to provide a detailed understanding of Remote and Rural Community Placements (RRCPs) which occur in the second year of a Doctor of Medicine programme.

Volatile compounds in blood headspace and nasal breath.

Breath analysis is a form of metabolomics that utilises the identification and quantification of volatile chemicals to provide information about physiological or pathological processes occurring within the body. An inherent assumption of such analyses is that the concentration of the exhaled gases correlates with the concentration of the same gas in the tissue of interest. In this study we have investigated this assumption by quantifying some volatile compounds in peripheral venous blood headspace, and in nasal breath collected in Tedlar bags obtained at the same time from 30 healthy volunteers, prior to analysis by selected ion flow tube mass spectrometry.

Methylnicotinate stimulated prostaglandin synthesis in patients with schizophrenia: A preliminary investigation.

Schizophrenia is a serious mental illness of unclear aetiology. The reduced ability of methylnicotinate to induce a topical vasodilatory response in patients with the disorder is well established. Methylnicotinate causes vasodilation via stimulating the release of prostaglandins (including prostaglandin D) in the skin which in turn leads to relaxation of vascular smooth muscle.

Dietary omega-3 polyunsaturated fatty acid supplementation in an animal model of anxiety.

A large body of evidence suggests that dietary supplementation with omega-3 fatty acids may ameliorate depressed mood. The magnitude of the effect varies between studies, however, ranging from none at all to being of clinical significance. Given that substantial comorbidity occurs between mood and anxiety disorders, suggesting that they have one or more pathophysiological mechanisms in common, we hypothesized that omega-3 fatty acids may be acting primarily to reduce anxiety rather than depression per se, a possibility which could underlie their variable effects on mood.

Quantification of methanol in the presence of ethanol by selected ion flow tube mass spectrometry.

The quantification of trace compounds in alcoholic beverages is a useful means to both investigate the chemical basis of beverage flavor and to facilitate quality control during the production process. One compound of interest is methanol which, due to it being toxic, must not exceed regulatory limits. The analysis of headspace gases is a desirable means to do this since it does not require direct sampling of the liquid material.

Brain and Liver Headspace Aldehyde Concentration Following Dietary Supplementation with n-3 Polyunsaturated Fatty Acids.

Reactive oxygen species react with unsaturated fatty acids to form a variety of metabolites including aldehydes. Many aldehydes are volatile enough to be detected in headspace gases of blood or cultured cells and in exhaled breath, in particular propanal and hexanal which are derived from omega-3 and omega-6 polyunsaturated fatty acids, respectively. Aldehydes are therefore potential non-invasive biomarkers of oxidative stress and of various diseases in which oxidative stress is thought to play a role including cancer, cardiovascular disease and diabetes.

Fungal demethylation of Kraft lignin.

Demethylation of industrial lignin has been for long coveted as a pathway to the production of an abundant natural substitute for fossil-oil derived phenol. In an attempt to possibly identify a novel Kraft lignin-demethylating enzyme, we surveyed a collection of fungi by using selected ion flow tube-mass spectrometry (SIFT-MS). This method readily identifies methanol resulting from lignin demethylation activity.

Breath ethane concentrations in healthy volunteers correlate with a systemic marker of lipid peroxidation but not with omega-3 Fatty Acid availability.

Ethane in human breath derives from lipid peroxidation, specifically the reaction between omega-3 fatty acids and reactive oxygen species. It has been proposed to be a non-invasive marker of oxidative stress, a deleterious process which may play an important role in the pathophysiology of several common diseases. It is unclear, however, whether ethane concentration actually correlates with systemic oxidative stress or whether it is primarily a marker of airway biochemistry.

Quantification of character-impacting compounds in Ocimum basilicum and 'Pesto alla Genovese' with selected ion flow tube mass spectrometry.

Basil (Ocimum basilicum) is an important flavourant plant which constitutes the major ingredient of the pasta sauce 'Pesto alla Genovese'. The characteristic smell of basil stems mainly from a handful of terpenoids (methyl cinnamate, eucalyptol, linalool and estragole), the concentration of which varies according to basil cultivars. The simple and rapid analysis of the terpenoid constituents of basil would be useful as a means to optimise harvesting times and to act as a quality control process for basil-containing foodstuffs.

Changes in oral trace gas concentrations following orthognathic surgery and intermaxillary fixation: a case study using selected ion flow tube mass spectrometry.

Orthognathic surgery is frequently accompanied by intermaxillary fixation. Intermaxillary fixation impedes the maintenance of effective oral hygiene and prolonged fixation can result in periodontal disease. A potential shorter term effect is the generation of oral malodour.

The reactions of a series of terpenoids with H(3) O(+) , NO(+) and O 2+ studied using selected ion flow tube mass spectrometry.

The reactions of H(3) O(+) , NO(+) and O 2+ with twelve terpenoids and one terpene, all of which occur naturally in plants and which possess important smell and flavourant properties, were characterized using Selected Ion Flow Tube Mass Spectrometry (SIFT-MS). The H(3) O(+) reactions resulted primarily in the formation of the proton transfer product and occasionally in a water elimination product. The NO(+) reactions instead generated the charge transfer product or NO(+) adducts, and occasionally alkyl fragments, or resulted in hydride abstraction.

Increased breath ethane levels in medicated patients with schizophrenia and bipolar disorder are unrelated to erythrocyte omega-3 fatty acid abundance.

Oxidative stress has been reported to be elevated in mental illness. Preliminary evidence suggests this phenomenon can be assessed non-invasively by determining breath levels of the omega-3 polyunsaturated fatty acid (PUFA) oxidation product ethane. This study compares alkane levels in chronic, medicated, patients with schizophrenia or bipolar disorder with those in healthy controls.

A preliminary investigation of exhaled breath from patients with celiac disease using selected ion flow tube mass spectrometry.

Background And Aims: Breath diagnostics, the measurement of volatile chemicals in human breath, is currently receiving attention as a technique for the detection of disease which, being non-invasive in nature, is particularly suited to screening for pre-symptomatic disease in healthy populations. A disorder in which more effective screening would be beneficial is celiac disease (CD), an under-diagnosed autoimmune disease of the small intestine characterized by nutritional malabsorption, which presents with diverse, and sometimes serious, symptoms. We aimed to determine whether breath analyses could be used to screen for the presence of CD.

The reactions of H(3)O(+), NO(+) and O(2) (+) with several flavourant esters studied using selected ion flow tube mass spectrometry.

The reactions of H(3)O(+), NO(+), and O(2) (+) with nineteen ester compounds occurring naturally in plants, and having important flavourant properties, were examined using selected ion flow tube mass spectrometry (SIFT-MS). The H(3)O(+) reactions primarily generate [R(1)COOR(2).H](+), and may also produce [R(2)](+) fragment ions and/or fragmentation within the ester linkage.

The use of selected ion flow tube mass spectrometry to detect and quantify polyamines in headspace gas and oral air.

Polyamines are a class of aliphatic compounds which include putrescine, cadaverine, spermine and spermidine. They are involved in a variety of cellular processes and have been implicated in a number of different pathophysiological mechanisms. Polyamines are volatile compounds having a distinctive odour normally perceived as being unpleasant.

Omega-3 polyunsaturated fatty acids and anxiety disorders.

Anxiety disorders are a common group of psychiatric illnesses which have significant personal, family and societal costs. Current treatments have limited efficacy in many patients highlighting a need for new therapeutic approaches to be explored. Anxiety disorders exhibit marked comorbity with mood disorders suggesting the existence of mechanistic similarities.

Stability of methylnicotinate in aqueous solution as utilized in the 'niacin patch test'.

Background: The topical application of methylnicotinate results in a localized vasodilatatory response which has been found to differ from that observed to occur in healthy controls in a variety of medical conditions. The stability of the drug in aqueous solution is unclear while difficulties can be encountered when preparing methylnicotinate solutions for this purpose. To aid in the determination of how long solutions of the drug should be stored before discarding we have used a collection of aged batches of methylnicotinate to determine the stability of the drug in aqueous solution.

Sub-parts per billion detection of trace volatile chemicals in human breath using selected ion flow tube mass spectrometry.

Background: Selected ion flow tube mass spectrometry (SIFT-MS) allows the real time quantification of trace gases in air. Due to its tolerance of high humidity levels the technique is particularly suited to the chemical analysis of breath. The detection limit of SIFT-MS has previously reported to be approximately 5 - 10 PPBV which is insufficient for the measurement of some low abundance constituents of breath.

A comparison of oxidative stress in smokers and non-smokers: an in vivo human quantitative study of n-3 lipid peroxidation.

Background: Cigarette smoking is believed to cause oxidative stress by several mechanisms, including direct damage by radical species and the inflammatory response induced by smoking, and would therefore be expected to cause increased lipid peroxidation. The aim was to carry out the first study of the relationship of smoking in humans to the level of n-3 lipid peroxidation indexed by the level of ethane in exhaled breath.

Methods: Samples of alveolar air were obtained from 11 smokers and 18 non-smokers.

Evidence from in vivo 31-phosphorus magnetic resonance spectroscopy phosphodiesters that exhaled ethane is a biomarker of cerebral n-3 polyunsaturated fatty acid peroxidation in humans.

Background: This study tested the hypothesis that exhaled ethane is a biomarker of cerebral n-3 polyunsaturated fatty acid peroxidation in humans. Ethane is released specifically following peroxidation of n-3 polyunsaturated fatty acids. We reasoned that the cerebral source of ethane would be the docosahexaenoic acid component of membrane phospholipids.

Increased levels of ethane, a non-invasive, quantitative, direct marker of n-3 lipid peroxidation, in the breath of patients with schizophrenia.

This study directly assessed whether there was a change in the level of exhaled ethane, which provides a non-invasive, quantitative, direct measure of n-3 lipid peroxidation, in the breath of patients with schizophrenia. Samples of alveolar air were obtained from 20 subjects with schizophrenia and 23 age- and sex-matched healthy control subjects. The air samples were analyzed for ethane using mass spectrometry.