Glucose transporter-4 in white blood cells of young and old sled dogs: a model for human biomarker development
The insulin responsive glucose transporter, GLUT4 is found predominantly in muscle and adipose cells. Maratou and others (2007) reported that there is GLUT4 in white blood cells (WBC) collected from human subjects in response to insulin activation. This study was designed to validate the presence of GLUT4 in white blood cells of sled dogs and furthermore to investigate whether changes in levels of the GLUT4 protein might be associated with aging. Additionally, we examined the blood insulin concentration of two populations of dogs, young and old, before and after a meal to observe their insulin response. It is documented in skeletal muscle that GLUT4 expression is increased as a result of conditioning, making sled dogs an excellent model in the circumpolar north for studying the effects of exercise, nutrition and diabetes (Felsburg 2002; Kararli 2006). Blood was withdrawn from 11 healthy sled dogs: 6 young (1-5 years) and physically fit, conditioned for racing and 5 old (7-13 years), retired from racing. The insulin response was determined using blood plasma and ELISA. The buffy coat (containing WBC) was collected with a glass pipette after centrifugation and washed and suspended in 1x phosphate buffer. GLUT4 was measured using ELISA kits (USCN Life Sciences). The results validate that GLUT4 is present in white blood cells in sled dogs. Age had no significant effect in the concentration of GLUT4 between the populations of old and young dogs. A significant difference in insulin levels pre and post meal in young (0.13 ± 0.03 ng/mL (pre), 0.22 ± 0.04 ng/mL (post), p < 0.05) and old (0.13 ± 0.02 ng/mL (pre), 0.22 ± 0.03 ng/mL (post), p < 0.05) dogs was observed, displaying the typical postprandial insulin spike. No significant difference was found in insulin concentration comparing old versus young dogs. Our data shows that white blood cells in young (40.4 ± 2.4 ng/mL) and old (35.3 ± 8.8 ng/mL) sled dogs have quantifiable but non-significant different GLUT4 levels (p > 0.05). Detecting GLUT4 via an ELISA in white blood cells, opens up minimally invasive avenues for studying the underlying molecular mechanisms associated with insulin resistance in more complex, dynamic and physiological systems. This project was the first step in developing a protocol for this simple, technique with a potential clinical application for diagnosing insulin resistance.
Medical comforts during the heroic age of Antarctic exploration
In the literature of the exploration of the Antarctic in the early 20th century, there are many references to 'medical comforts'. While 'medical comforts' was sometimes used as a euphemism for alcoholic beverages, the term, which originated in the army, covered all foods and drinks used for the treatment and prevention of illness and during convalescence. This article describes the use of medical comforts during the Antarctic expeditions of the so called 'heroic age'. Apart from alcohol, medical comforts included beef extracts, milk extracts and arrowroot. These products were extensively advertised to the medical and nursing professions and to the general public and the Antarctic connection was sometimes used in the advertising. The products were largely devoid of vitamins and their use may have contributed to some of the disease that occurred on these expeditions.
'Polar anaemia': cardiac failure during the heroic age of Antarctic exploration
On the expedition (1897-1899), Dr F.A. Cook described a disease that he called 'polar anaemia' and on this expedition it affected most of the expedition members and caused one death. The symptoms were shortness of breath, abnormalities of the pulse and oedema (swelling of the legs) and the disease was clearly cardiac failure. During the heroic age of Antarctic exploration a similar disease affected at least eight other expeditions causing five other deaths. This disease was very similar (and probably identical) to a disease affecting (mostly) Scandinavian seamen and called 'ship beri-beri'. Both diseases were almost certainly what is now called wet beri-beri due to thiamine (vitamin B1) deficiency though most sufferers were probably also vitamin C deficient and some may have had both beri-beri and scurvy. It may have been exacerbated by invalid diets. This paper describes the disease and how it was considered and treated at the time.
The paranormal Arctic: Lady Franklin, Sophia Cracroft, and Captain and "little weesy" Coppin
Franklin's "Cemented Tomb": The Jamme Report of 1928 Revisited
Few details are known about the fate of the Franklin Expedition after it departed England in 1845. What we do know is derived from the archaeological record, Inuit testimony and brief communications written in 1847 and 1848 from the Expedition. During the 1860s, Charles Francis Hall went to the Arctic in search of survivors, papers, and relics. During Hall's second expedition, two Inuit testimonies emerged which reported unusual site(s) on the Westcoast of King William Island which were reputedly build by the Expedition. Hall believed these sites were either a burial site or a cemented document vault(s). The first testimony, recorded by Hall himself, was obtained from a Pelly Bay Inuk, Sŭ-pung-er, in 1866. The second, was collected from Pelly Bay Inuit by members of Hall's support team, including Peter Bayne, in Hall's absence in 1868. Eventually, the second testimony was sold to the Canadian Government in the form of a report written by George Jamme after Bayne's death in 1928. Until now, only extracts of the Jamme Report have been available. This paper describes the background to the Jamme report and presents it in its entirety along with critiques so that scholars in the future may have this tool.
