Bio Aging Midterm Discussion papers and Aging patterns.txt

First to determine the Type III aging pattern, doing research on oak trees (theorized from Raymond Pearl)

Dog breeding studies: showed that lifespan increases in dog breeds with larger brain:body ratio

Showed that increase in metabolic activity, along with an increase in temperature causes increase in mortality rates in houseflies

• showed that reduced calorie diet in mice showed:
• 1. Increase in % survival
• 2. Decrease in body mass
• 3. decrease in TUMOR mortality

• Carried out LARGEST study with MedFlys: showing NOT exhibiting Gompertz pattern.
• Flies had higher survival rates as age INCREASED

discovered that immortal amoebas could be transformed to 'spanned' amoebas with NUTRIENT DEPRIVATION, even briefly

• Showed Vitamin E supplementation for paramecium cells increases lifespan
• Data showed a Type I Gompertzian slope curve

• Showed castrated males vs intact had more higher life expectancy.
• Also showed mentally retarded males exhibited hyperbolic pattern of age-related mortality increase

• Looked at British aristocracy
• showed that women age of first child birth and # of children correlate with longevity of females
• Longer you wait until first child, and if only have 1 child: show longest longevity

• Using Drosophila melanogaster, show the increase in Vitamin A consumption is correlated to increase in longevity
• Too much Vit A can be detrimental, however, causing a decrease in longevity

• gene redundancy R: Determines how RAPID mortality rate Increases
• redundancy may improve cell survivorship by reducing rate of loss of genetic info
• small damage rate u (mew) and large redundancy = increase in survival

• qx= qo (e)a(x)^n with N=1
• Type I:
• Linear curve on a semi-logarithmic mortality plot
• Concave slope on double log plot
• delta ln qx is POSITIVE and CONSTANT, so doubledelta q is ZERO (inverse Gomp w/type III shows neg delta lnqx)
• Declining life expectancy with age
• Constant MRDT with age

• qx=qo(e)a(x)^n
• Type I:
• Mortality INCREASES at accelerating rate
• ConCAVE slope for semi and double log plot
• delta lnqx is POSITIVE and INCREASING
• Declining life-expectancy with age
• Declining MRDT with age

• qx=qo(x+1)^n with n > 0
• ConVEX slope on semi-log plot
• Linear on double log plot
• delta lnqx Positive and DECREASING, double delta lnq is NEGATIVE
• Declining life-expectancy with age
• Increasing mortality rate doubling time w/age

• lx = 1-(1-(1-u)^x)^R
• Type I:
• Slowest rate of senescence
• Convex slope on semi-logarithmic (and double) mortality plot
• Declining life expectancy with age
• Increasing MRDT with age
• ONLY with NO upper limit to Maximum lifespans

• In stationary phase, immortal bacteria (Prokaryotes) exhibited REDUCED viability & INCREASED mortality
• Followed Gompertz pattern: decrease in life expectancy with age
• bacteria termed immortal b/c although they have rate of aging, they can sustain damage as long as their growth rates are high

• type I: Prob of death (qx) continuously INCREASING, with Life expectancy (ex) going DOWN
• type II: qx and ex stay SAME
• type III: probability of death (qx) DECREASES

• # of prop. of ppl dying from age x to x+t
• dx=lx - l(x+t)

qx=dx/lx

• avg # of prop. of ppl surviving from age x to x+t
• Lx= (lx + l(x+t))/2

• Total # of organism-age-intervals in lifetable
• Tx=sum of Lx (Lx + L(x+t) + L(x+2t)...)

ex = (Tx)(t) / (lx)

# of prop. of ppl surviving at age x

age interval

time interval b/w survival measurements