ABSTRACT
OBJECTIVE: To compare the medicines included in national essential medicines lists with the World Health Organization's (WHO's) Model list of essential medicines, and assess the extent to which countries' characteristics, such as WHO region, size and health care expenditure, account for the differences. METHODS: We searched the WHO's Essential Medicines and Health Products Information Portal for national essential medicines lists. We compared each national list of essential medicines with both the 2017 WHO model list and other national lists. We used linear regression to determine whether differences were dependent on WHO Region, population size, life expectancy, infant mortality, gross domestic product and health-care expenditure. FINDINGS: We identified 137 national lists of essential medicines that collectively included 2068 unique medicines. Each national list contained between 44 and 983 medicines (median 310: interquartile range, IQR: 269 to 422). The number of differences between each country's essential medicines list and WHO's model list ranged from 93 to 815 (median: 296; IQR: 265 to 381). Linear regression showed that only WHO region and health-care expenditure were significantly associated with the number of differences (adjusted R2 : 0.33; P < 0.05). Most medicines (1248; 60%) were listed by no more than 10% (14) of countries. CONCLUSION: The substantial differences between national lists of essential medicines are only partly explained by differences in country characteristics and thus may not be related to different priority needs. This information helps to identify opportunities to improve essential medicines lists.
Subject(s)
Developing Countries/statistics & numerical data , Drugs, Essential , Drugs, Essential/economics , Europe , Gross Domestic Product , Health Expenditures , Humans , Linear Models , Regression Analysis , World Health OrganizationABSTRACT
Atrial Fibrillation is the most common sustained cardiac arrhythmia worldwide harming millions of people every year. Atrial Fibrillation (AF) abruptly induces rapid conduction between atrial myocytes which is associated with oxidative stress and abnormal calcium handling. Unfortunately this new equilibrium promotes perpetuation of the arrhythmia. Recently, in addition to being the major source of oxidative stress within cells, mitochondria have been observed to fuse, forming mitochondrial networks and attach to intracellular calcium stores in response to cellular stress. We sought to identify a potential role for rapid stimulation, oxidative stress and mitochondrial hyperfusion in acute changes to myocyte calcium handling. In addition we hoped to link altered calcium handling to increased sarcoplasmic reticulum (SR)-mitochondrial contacts, the so-called mitochondrial associated membrane (MAM). We selected the C2C12 murine myotube model as it has previously been successfully used to investigate mitochondrial dynamics and has a myofibrillar system similar to atrial myocytes. We observed that rapid stimulation of C2C12 cells resulted in mitochondrial hyperfusion and increased mitochondrial colocalisation with calcium stores. Inhibition of mitochondrial fission by transfection of mutant DRP1K38E resulted in similar effects on mitochondrial fusion, SR colocalisation and altered calcium handling. Interestingly the effects of 'forced fusion' were reversed by co-incubation with the reducing agent N-Acetyl cysteine (NAC). Subsequently we demonstrated that oxidative stress resulted in similar reversible increases in mitochondrial fusion, SR-colocalisation and altered calcium handling. Finally, we believe we have identified that myocyte calcium handling is reliant on baseline levels of reactive oxygen species as co-incubation with NAC both reversed and retarded myocyte response to caffeine induced calcium release and re-uptake. Based on these results we conclude that the coordinate regulation of mitochondrial fusion and MAM contacts may form a point source for stress-induced arrhythmogenesis. We believe that the MAM merits further investigation as a therapeutic target in AF-induced remodelling.
Subject(s)
Calcium/metabolism , Mitochondria/metabolism , Models, Biological , Muscle Fibers, Skeletal/metabolism , Oxidative Stress , Acetylcysteine/pharmacology , Animals , Calcium Signaling/drug effects , Cell Differentiation/drug effects , Mice , Mitochondria/drug effects , Mitochondria/ultrastructure , Mitochondrial Dynamics/drug effects , Mitochondrial Membranes/drug effects , Mitochondrial Membranes/metabolism , Muscle Contraction/drug effects , Muscle Fibers, Skeletal/cytology , Muscle Fibers, Skeletal/ultrastructure , Mutant Proteins/metabolism , Oxidation-Reduction/drug effects , Oxidative Stress/drug effects , Protein Transport/drug effects , Reactive Oxygen Species/metabolism , Sarcoplasmic Reticulum/drug effects , Sarcoplasmic Reticulum/metabolismABSTRACT
BACKGROUND: Established methods for assessing surgical performance face limitations. Global rating scales and procedure-specific checklists are resource intensive and rely on expert opinions. Alternatives that use technology to track hand movements, such as magnetic and optical tracking systems, are generally expensive and ill suited to the surgical environment. METHODS: The authors present a new platform that integrates a novel, low-cost optical tracking system, magnetic tracking technology and a videographic recording system to quantify surgical performance synchronously across all modalities. The validity of this platform was tested by examining its ability to differentiate between the performance of expert and novice participants on a basic surgical task. RESULTS: Each modality was able to differentiate between expert and novice participants, and metrics were well correlated across modalities. CONCLUSIONS: The authors have developed a platform for assessing surgical performance. It can operate in the absence of expert raters and has the potential to provide immediate feedback to trainees.
