Metabolic body mass

So the term BM was introduced and called metabolic body mass (MBM), which is, in fact, proportional to HL within a species or related species. Assuming a proportionality of HL and MBM the heat balance of the body requires a proportionality between EE and MBM too. This, however, introduces a differentiation of indirect calorimetric measurements by body mass. On first hand there is calorimetry on humans and large (farm) animals, often done in relatively large (and convenient) calorimetric chambers with volumes (V) of up to 25 m On the other hand there is indirect calorimetry on small (laboratory) animals, even organ tissue or cell clusters. Small animal calorimetry can perfectly be done in relative small cages with volumes of Just a few litres, whereas tissues or cell clusters can be investigated in small ampoules [25]. 

The body mass of mice, rats, humans and horses varies from about 20 g, 250 g, 75 kg to 1000 kg, repectively. This is about 50,000 times. The typical chamber (cage) volume is somehow related to body mass and has a comparable variation. On the other hand the metabolic body mass varies only between 0.02 k , 0.35 k 25.5 k and 118 kg" about 3333 times. So does EE, O2 and the flow rate of the system too. This implements typical time constants between some min in small animal measurements to up to some 5 h in human measurements. So human calorimetrists had to employ equation (17) to improve... 

Porter, K. Brand, M.D. (1993). Body mass dependence of H leak in mitochondria and its relevance to metabolic rate. Nature 362,628-630. 

CF patients have larger volumes of distribution of many antibiotics due to an increased ratio of lean body mass to total body mass and lower fat stores. CF patients also have an enhanced total body clearance, although the exact mechanism has not been determined. Increased renal clearance, increased glomerular filtration rate, decreased protein binding, increased tubular secretion, decreased tubular reabsorption, extrarenal elimination, and increased metabolism have all been proposed as possible reasons for the increased clearance. 

As amisulpride has no hepatic metabolism, low protein binding, and is directly excreted in urine, there is little reason to suspect pharmacokinetic ethnic differences. Of course body mass and pharmacodynamic differences might occur, but to date have received little investigative attention. 

Interestingly, it has been shown that supplementation of greenfinches with lutein and zeaxanthin at a ratio of 20 1 increases plasma levels of triglycerides and bird body mass (Horak et al., 2006). These data suggest that xanthophylls may affect lipid metabolism. 

After oral ingestion, ethanol pharmacokinetics must take into account (1) Absorption from the gastrointestinal tract. Since ethanol is absorbed most efficiently from the small intestines, the rate of gastric emptying is an important factor that governs the rate of rise of blood alcohol concentration (BAC), i.e., the slope of the ascending limb of the BAC-time curve, and the extent of first pass metabolism of ethanol by the liver and stomach. (2) Distribution of ethanol in the body. Ethanol distributes equally in total body water, which is related to the lean body mass of the person, and (3) the elimination of ethanol from the body, which occurs primarily by metabolism in the liver, first to acetaldehyde and then to acetate [7]. 

In individuals who took thyroid hormones, 80% of the weight lost was lean body mass (muscle and bone) rather than excess fat. People taking these extracts experienced muscle weakness and bone breakdown, which led to a condition called osteoporosis, in which bones are weakened and the risk of bone fractures or breaks is increased. Thyroid hormone extracts also made the heart work harder by increasing metabolism, which led to problems such as increased heart rate, palpitations, and irregular heartbeat. These problems were potentially life threatening When the heart beats abnormally (or not at all), it is unable to pump blood and oxygen to the brain and body. Individuals die suddenly from this condition because the brain can only function for a few minutes without oxygen and nutrients. 

There is a decrease in basal metabolic rate with a decline in lean body mass and less physical activity. The caloric requirement may, therefore, be reduced... 

Clearance of nicotine is decreased in the elderly (age >65) compared to adults (Molander et al. 2001). Total clearance was lower by 23%, and renal clearance lower by 49% in the elderly compared to yonng adults. Lower nicotine metabolism in the elderly may be contribnted to by rednced liver blood flow, since no decrease in CYP2A6 protein levels or nicotine metabolism in liver microsomes due to age has been detected (Messina et al. 1997). No differences in steady-state nicotine plasma levels or estimated plasma clearance valnes were detected in three age gronps (18-39, 40-59, and 60-69 years) nsing patches with the same nicotine content (Gonrlay and Benowitz 1996). The volnme of distribntion of nicotine is lower in older snbjects due to a decrease in lean body mass (Molander et al. 2001). 

Forty healthy participants, 25 female and 15 males, aged 19-33 years with a body mass index between 18 and 24 kg/m took part in the study. Excluding criteria were smoking, current dental surgery, illness of the pharynx or the cavity of the mouth, malabsorption, long-time medication, use of a toothpaste with vitamin A during the last 2 months prior to the study, pregnancy, and metabolic diseases. 

However, the physiology of ageing includes poorer gastrointestinal absorption, somewhat reduced hepatic drug metabolism, and, commonly, a loss of lean body mass. While all of these have been documented, none is of as great a significance as the loss of renal excretory function which is invariably present in old age. 

Old age Reduced absorption ] Reduced metabolism 1 —> Loss of body mass J Reduced renal function — Few practical consequences Risk of toxicity with renally-cleared drugs... 

As previously mentioned, the detection period for a drug depends on a number of factors, including the type of opiate, the type of sample, the frequency of drug use, metabolic rate, age, body mass, drug tolerance, and overall health. Generally speaking opium can be detected for 5-7 days after its use. Other opiates such as heroin and codeine have significantly shorter detection periods (Table 10.3). 

Improved metabolic state, increased lean body mass, sense of well-being Growth hormone deficiency in adults... 

Your basal metabolism requires approximately 46 Calories per hour (h) per 100 pounds (lb) of body mass to carry out basic functions required for life, apart from doing any kind of exercise. A person walking at 2 miles per hour on a level path requires approximately 45 Calories per hour per 100 pounds of body mass beyond basal metabolism. The same person swimming at 2 miles per hour consumes 360 Calories per hour per 100 pounds beyond basal metabolism. 

The brain has a very high rate of metabolism. Although accounting for only 1 / 50 of the body mass its utilization of energy amounts to 1/ 5 of the basal metabolism. This is 20 watts and is nearly constant day and night. It reflects the unusually active metabolism of neurons, a major part of which can be attributed to the sodium-potassium ion pumps in the membranes and to the maintenance of the excitable state.5363 The source of energy for these processes is the ATP that is... 

A 54-year-old woman with type 2 diabetes had poor metabolic control, despite using 60-80 units of shortacting and long-acting human insulins for 10 years (34). Transfer to insulin lispro reduced the daily amount of insulin to 28 units. Insulin specific antibodies fell from 2.7 to 0.3% and cross-reactive antibodies, binding both human insulin and insulin lispro, fell from 44 to 16%. Specific insulin lispro antibodies rose from 0 to 0.3%. HbAic fell from 9.1% to 6.8% and body mass index from 30 to 27, probably because of the reduced dose of insulin. 

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