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== '''[[Diabesity]]''' ==
== '''[[Los Alamos National Laboratory]]''' ==
''by  [[User:Gareth Leng|Gareth Leng]], [[User:Hannah Frost|Hannah Frost]], [[User:Luke Kennedy Burke|Luke Kennedy Burke]], [[User:Charlie Player|Charlie Player]] and [[User:Katie Rowland|Katie Rowland]]
''by  [[User:Milton Beychok|Milton Beychok]], [[User:Ro Thorpe|Ro Thorpe]] and [[User:Daniel Mietchen|Daniel Mietchen]]
 
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The term '''diabesity''' was coined by [https://vpn.ucsf.edu/oby/journal/v19/n3/full/,DanaInfo=www.nature.com+oby2010334a.html Ethan Sims] in 1973, to describe the close relationship between [[diabetes mellitus type 2]] (T2DM) and [[obesity]]. Their findings suggested that by overfeeding young men, with no previous family history of diabetes, the initial signs of diabetes were induced. This excess consuption led to increases in [[insulin]] production, plasma [[glucose]], [[triglycerides]] and eventually impaired glucose tolerance; all signs predisposing one to T2DM and obesity<ref>
'''Los Alamos National Laboratory''' (LANL), located in [[Los Alamos]], [[New Mexico]], is one of several [[U.S. Department of Energy]] (DOE) national laboratories.  It is noteworthy as the site where the first [[atomic weapon]] was developed under a heavy cloak of secrecy during [[World War II]], and has been known variously as '''''Site Y''''', '''''Los Alamos Laboratory''''', and '''''Los Alamos Scientific Laboratory'''''.  Today, it is recognized as one of the world's leading science and technology institutes.
Sims EAH ''et al.'' (1973) Endocrine and metabolic effects of experimental obesity in man, ''Recent Prog Horm Res'' 29:457–96</ref><ref>Haslam DW, James WP (2005) Obesity''Lancet'' 366:1197–209</ref>


T2DM is a disorder where cells fail to take up glucose from the blood. Glucose is the fuel for respiration which produces energy for our cells to function properly. Diabetes mellitus is the foremost cause of kidney failure ([[diabetic nephropathy]]), blindness ([[diabetic retinopathy]]), and amputation in adults ([[diabetic neuropathy]]). People with this disease lack the ability to utilize the hormone [[insulin]]. Insulin is produced by the [[pancreas]] after a meal inresponse to increased concentrations of glucose in the blood. The insulin signal attaches to specific receptors on the surface of target cells, causing them to switch on their glucose-transporting machinery. People with T2DM have normal or even elevated levels of insulin in their blood, and normal insulin receptors, but the binding of insulin to its receptors does not turn on the glucose-transporting machinery.
{{Image|Trinity test.jpg|right|200px|Trinity test of an [[Nuclear weapon|atomic bomb]] on July 15, 1945 at 0.016 seconds after detonation. The fireball was about 200 metres wide.}}
Since 2006, LANL has been managed and operated by [[Los Alamos National Security, LLC]] (LANS).<ref name=LANS/>
LANL's self-stated mission is to ensure the safety, security, and reliability of the nation's nuclear deterrent.<ref name=LANL-Mission/> Its research work serves to advance [[Biology|bioscience]], [[chemistry]], [[computer science]], [[Earth science|earth]] and [[environmental science]]s, [[materials science]], and [[physics]] disciplines.<ref name=LANL-About/><ref name=LANL-Overview/>


Proteins called [[IRS proteins]] (insulin receptor substrate) bind with the insulin receptor inside the cell. The receptor responds by adding a phosphate group onto the IRS molecules. This rouses the IRS molecules into action, and they activate a variety of processes, including an enzyme that turns on the glucose transporter machinery. When the IRS genes are deliberately inactivated in [[transgenic]] “knockout” mice, T2DM results. However, there are no IRS gene mutations in inherited T2DM; the IRS genes are normal. This suggests that in T2DM something is impeding with the action of the IRS proteins. An estimated 80% of those who develop T2DM are obese.
===History===


===Visceral fat accumulation and type 2 diabetes===
The [[Manhattan Project]] was the secret [[United States]] project conducted primarily during [[World War II]] with the participation of the [[United Kingdom]] and [[Canada]] that culminated in developing the world's first [[nuclear weapon]], commonly referred to at that time as an ''atomic bomb''.  
Excess visceral adipose tissue increases the risk for T2DM. Excess fat within the [[abdomen]], known as [[visceral adiposity]], creates a serious health risk of metabolic complications independent from accumulation of adipose tissue in other regions: visceral adiposity is related with an increase in ''[[insulin resistance]]'', whereas abdominal subcutaneous fat is not. (''Insulin resistance'' describes the impaired ability of insulin to suppress hepatic glucose output and promote glucose disposal in the periphery.) As T2DM gets worse, patients have higher blood sugar levels ([[hyperglycaemia]]) because the [[pancreatic beta cells]] are unable to make enough insulin. In insulin resistance, normal amounts of insulin are unable to produce a normal response from adipose, muscle and liver cells. Cnop ''et al.'' showed that visceral fat is the best predictor of insulin sensitivity whilst subcutaneous fat establishes leptin levels <ref>Cnop''et al.'' (2002) The concurrent accumalation of intra-adominal and subcutaneous fat explains the association between insulin resistance and plasma leptin concentrations. ''Diabetes'' 51:1005-15</ref>


In 1994, a new hormone was found, called [[leptin]], that provides feedback to the brain of the level of fat in the body. Leptin suppresses appetite, but most obese people have very high leptin levels, as  leptin is secreted by adipose cells. Therefore, obesity is not generally caused by a deficiency in leptin; instead there seems to be a defect in leptin signalling. Adipocytes also produce an array of other peptides including [[adiponectin]], [[resistin]] and [[TNF alpha]]. They act on peripheral tissues and thereby affect insulin sensitivity and the processes involved in substrate metabolism.  
The project was initiated in 1939 by [[U.S. President]] [[Franklin Delano Roosevelt]] after he received a letter from physicist [[Albert Einstein]] (drafted by fellow physicist [[Leó Szilárd]]) urging the study of [[nuclear fission]] for military purposes, under fears that [[Nazi Germany]] would be first to develop nuclear weapons. Roosevelt started a small investigation into the matter, which eventually became the massive [[Manhattan Project]] that employed more than 130,000 people at universities across the United States, the United Kingdom and Canada as well as at the three major design, development and production facilities: Los Alamos; Hanford, Washington; and Oak Ridge, Tennessee.


''[[Diabesity|.... (read more)]]''
''[[Los Alamos National Laboratory|.... (read more)]]''


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Revision as of 21:03, 1 March 2012

Los Alamos National Laboratory

by Milton Beychok, Ro Thorpe and Daniel Mietchen

Los Alamos National Laboratory (LANL), located in Los Alamos, New Mexico, is one of several U.S. Department of Energy (DOE) national laboratories. It is noteworthy as the site where the first atomic weapon was developed under a heavy cloak of secrecy during World War II, and has been known variously as Site Y, Los Alamos Laboratory, and Los Alamos Scientific Laboratory. Today, it is recognized as one of the world's leading science and technology institutes.

(PD) Photo: Berlyn Brixner
Trinity test of an atomic bomb on July 15, 1945 at 0.016 seconds after detonation. The fireball was about 200 metres wide.

Since 2006, LANL has been managed and operated by Los Alamos National Security, LLC (LANS).[1] LANL's self-stated mission is to ensure the safety, security, and reliability of the nation's nuclear deterrent.[2] Its research work serves to advance bioscience, chemistry, computer science, earth and environmental sciences, materials science, and physics disciplines.[3][4]

History

The Manhattan Project was the secret United States project conducted primarily during World War II with the participation of the United Kingdom and Canada that culminated in developing the world's first nuclear weapon, commonly referred to at that time as an atomic bomb.

The project was initiated in 1939 by U.S. President Franklin Delano Roosevelt after he received a letter from physicist Albert Einstein (drafted by fellow physicist Leó Szilárd) urging the study of nuclear fission for military purposes, under fears that Nazi Germany would be first to develop nuclear weapons. Roosevelt started a small investigation into the matter, which eventually became the massive Manhattan Project that employed more than 130,000 people at universities across the United States, the United Kingdom and Canada as well as at the three major design, development and production facilities: Los Alamos; Hanford, Washington; and Oak Ridge, Tennessee.

.... (read more)

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