Dr Rajiv Desai
An Educational Blog
ZIKA
ZIKA: ______ _____ Prologue: On 18 April 1947, a rhesus monkey that researchers identified as 766 ran a fever of 39.7°C, about 2°C higher than normal. The monkey was part of a study hunting for yellow fever virus and was living in a cage on a platform built into the tree canopy in the 1.5-kilometer-long Zika Forest, which runs adjacent to an arm of Lake Victoria in Uganda. Three days later, the investigators took a blood sample from Rhesus 766 and injected it into the brains of Swiss albino mice. The mice “showed signs of sickness” after 10 days, and the researchers harvested their brains, from which they isolated a “new filterable transmissible agent.” Come January of the following year, the same researchers trapped mosquitoes from these canopy platforms and took them to the lab, hoping to isolate yellow fever virus. Others had shown that one of these species they […]
SWEATING
SWEATING: _____ _____ Prologue: Sweating is an essential and natural biological process that starts soon after we are born. Sweat is a weak salt solution produced by the sweat glands of skin. These are distributed over the entire body but are most numerous on the palms and soles. Since the time of the ancient Greeks, the significance of sweating has been recognized, whereas our understanding of the mechanisms and controllers of sweating has largely developed during the past century. Heat dissipation is vital for our survival during exercise and heat stress. In humans, the primary mechanism of heat dissipation, particularly when ambient temperature is higher than skin temperature, is evaporative heat loss secondary to sweat secretion from sweat glands. Normally humans produce as much as one liter of sweat per day; however most of this evaporates as soon as it is produced so we don’t notice it. The body produces […]
PULSE OXIMETRY
PULSE OXIMETRY _____ Prologue: All of us know how important oxygen is for our survival. Hypoxia means low oxygen supply and/or utilization by organ or tissue. Hypoxemia means low oxygen content of arterial blood. Hypoxaemia invariably leads to hypoxia but hypoxia can occur even without hypoxaemia. Arterial blood oxygen saturation is now considered the 5th vital sign, joining: temperature, respiratory rate, heart rate and blood pressure. Hypoxemia can be present before recognizable signs of respiratory distress become evident and the traditional sign of circumoral cyanosis is a late indicator of decreased oxygenation. Blood gas analysis was for many years the only available method of detecting hypoxemia in critically ill patients, but this technique is painful, has potential complications, and does not provide immediate or continuous data. Pulse oximetry is an objective estimation of oxygenation, and it is simple, reliable, and accurate when used appropriately. It has the unique advantage of […]
YOGA
YOGA: _ Marilyn Monroe performs dhanurasana (bow pose) in 1948: Indra Devi opened yoga studio in Hollywood in 1948 and discovered ready students among movie stars, who found yoga’s breathing and relaxation techniques useful to their work. Her students included Greta Garbo, Gloria Swanson and Marilyn Monroe. ______ Prologue: A considerable number of studies have identified prayer as a frequent and favoured coping method among patients providing each patient with comfort and strength. A variety of studies have attempted to test the efficacy of prayer and found no medical benefit. Prayers offered by strangers had no effect on the recovery of people who were undergoing heart surgery, a large and well-constructed study proved in 2006. The Cochrane Collaboration published a thorough review reaching the same conclusion in 2011 and counselled, “We are not convinced that further trials of this intervention should be undertaken and would prefer to see any resources […]
NET NEUTRALITY
NET NEUTRALITY: _ _ I am reminded of Abraham Lincoln’s remark: “The world has never had a good definition of the word liberty. We all declare for liberty, but in using the same word we do not mean the same thing.” Substitute ‘net neutrality’ for ‘liberty’, and that’s where we are today. The Internet has unleashed innovation, enabled growth, and inspired freedom more rapidly and extensively than any other technological advance in human history. Its independence is its power. Net neutrality means internet service providers (ISPs) should treat all data on internet equally. The ISPs have structural capacity to determine the way in which information is transmitted over the internet and the speed at which it is delivered. And the present internet network operators, principally large telephone and cable companies—have an economic incentive to extend their control over the physical infrastructure of the internet to leverage their control of internet […]
