Intrapulmonary shunting is a key contributor to hypoxia in COVID-19: An update on the pathophysiology.

Background: The pathophysiology of COVID-19 remains poorly understood. We aimed to estimate the contribution of intrapulmonary shunting and ventilation-to-perfusion (VA/Q) mismatch using a mathematical model to construct oxygen-haemoglobin dissociation curves (ODCs).

Methods: ODCs were constructed using transcutaneous pulse oximetry at two different fractions of inspired oxygen (FiO2).

The introduction of a paediatric ENT and anaesthesia skills course in Kilimanjaro Christian Medical Centre hospital, (KCMC), Moshi, Tanzania.

Human factors and a safe operating theatre environment are of paramount importance, wherever surgery is undertaken. The majority of patients in sub-Saharan Africa do not yet have access to safe surgery. The Paediatric ENT Skills and Airway Course introduced and evaluated here was designed to improve outcomes and safety in a typical East African environment.

Case report series: revisiting third and fourth pharyngeal arch anomalies, - are they thymopharyngeal duct remnants?

Background: Pharyngeal arch anomalies are the second most common form of head and neck congenital defect. The second arch anomalies are the most common, and compromise 95% of cases. Little is known about the 3rd and 4th arch anomalies as they are extremely rare.

Intrapulmonary shunt measured by bedside pulse oximetry predicts worse outcomes in severe COVID-19.

https://bit.ly/2KVv0m2

Metabolic basis to Sherpa altitude adaptation.

The Himalayan Sherpas, a human population of Tibetan descent, are highly adapted to life in the hypobaric hypoxia of high altitude. Mechanisms involving enhanced tissue oxygen delivery in comparison to Lowlander populations have been postulated to play a role in such adaptation. Whether differences in tissue oxygen utilization (i.

Nitrate enhances skeletal muscle fatty acid oxidation via a nitric oxide-cGMP-PPAR-mediated mechanism.

Background: Insulin sensitivity in skeletal muscle is associated with metabolic flexibility, including a high capacity to increase fatty acid (FA) oxidation in response to increased lipid supply. Lipid overload, however, can result in incomplete FA oxidation and accumulation of potentially harmful intermediates where mitochondrial tricarboxylic acid cycle capacity cannot keep pace with rates of β-oxidation. Enhancement of muscle FA oxidation in combination with mitochondrial biogenesis is therefore emerging as a strategy to treat metabolic disease.

Inorganic nitrate promotes the browning of white adipose tissue through the nitrate-nitrite-nitric oxide pathway.

Inorganic nitrate was once considered an oxidation end product of nitric oxide metabolism with little biological activity. However, recent studies have demonstrated that dietary nitrate can modulate mitochondrial function in man and is effective in reversing features of the metabolic syndrome in mice. Using a combined histological, metabolomics, and transcriptional and protein analysis approach, we mechanistically defined that nitrate not only increases the expression of thermogenic genes in brown adipose tissue but also induces the expression of brown adipocyte-specific genes and proteins in white adipose tissue, substantially increasing oxygen consumption and fatty acid β-oxidation in adipocytes.

Tissue-specific changes in fatty acid oxidation in hypoxic heart and skeletal muscle.

Exposure to hypobaric hypoxia is sufficient to decrease cardiac PCr/ATP and alters skeletal muscle energetics in humans. Cellular mechanisms underlying the different metabolic responses of these tissues and the time-dependent nature of these changes are currently unknown, but altered substrate utilization and mitochondrial function may be a contributory factor. We therefore sought to investigate the effects of acute (1 day) and more sustained (7 days) hypoxia (13% O₂) on the transcription factor peroxisome proliferator-activated receptor α (PPARα) and its targets in mouse cardiac and skeletal muscle.