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It's not a very catchy name,
is it? 它是很难记住的名字，是吧？ Yes, I know --
"Engineered Negligible Senescence" has ten syllables and is not the
world's most memorable, or indeed self-explanatory, phrase. But it is a good
name for our ultimate goal, honest -- as well as SENS being a catchy acronym.
Here's an explanation. I'm afraid it starts with a rather long preamble, but
trust me, it's worth it. 是的，我知道—“程控可忽略衰老”有10个音节，不是大家都能记住的词语，可以说实在不是不言自明的词组。但是，对于我们的最终的、真正的目标来说，它是一个好名字，SENS也是一个好记的缩写词。这里有一个解释。我恐怕要有很长的导言，但相信我，它是值得的。 First, let's
be precise: our ultimate goal is the availability to the entire human race of
technology that will restore them to whatever degree of youth they desire and
keep them there for as long as they want. That's a bit stronger than simply
"a cure for aging" -- it says that the cure should be available (at a
price that they can afford, of course) to absolutely anyone who wants it. But
then, what does "youth" mean? 第一，让我们说得准确点：我们的最终目标是能够把如下技术应用于整个人类：该项技术能恢复他们希望的年轻程度，并且只要他们希望保持在这个程度就保持在这个程度。这比单是“治愈老化”语气强一些 — 假定治愈是每个人绝对想要的现成技术（当然，以他们付得起的价格）。那么，“年轻”的意思是什么？ I don't think
many 70-year-olds will want therapies that erase all the knowledge that they've
gained in the second half of their life, for example, nor their taste for music
that is eschewed by the younger generation. No -- what "youth" means
for our purposes is physical robustness and vitality. 我不认为，例如，很多70岁老人想要抹去他们他们生命中第二个一半所获得的知识，也不想抹去年轻一代所避开的他们的音乐品味。不 — 对于我们的目的而言，“年轻”意味着精力充沛和生机勃勃。 That's where
things get tricky. We know aging when we see it, but it is actually very hard
indeed to measure .... until it's over. It isn't very hard to distinguish a
dead person from a live one, but telling the difference (accurately, mind --
not just 70% of the time) between a person who's likely to live another 10
years and one who's likely to live another 20 is very much harder. 那就是事情变得棘手的地方。我们知道老化，因为我们可以看到它，但是实际上它很难被测量……直到结束。不难区别死人和活人，但是，要告诉一个人可能再活10岁，另一个人可能再活20岁，说出这其中的区别（准确地说，请注意 — 不止70%是时候是这样）就难多了。 We have one
very approximate measure of how long someone's likely to live, namely how long
they've lived already, and even though scientists have tried very hard they
have so far failed to find an appreciably better one. 我们可以非常近似地测量某人可能活多久，那就是，他们已经活了多久，即使科学家竭尽全力，但是，他们迄今未能发现一种哪怕好一点的方法。
But this isn't
as hopeless as you might think. We can say, very clearly, that loss of physical
robustness and vitality is what kills most of us (those that don't die of
homicide and such like). It makes us less resistant to diseases like flu that
we can fight off easily in our earlier years. It makes us more likely to break
bones if we fall, and those breaks take longer to heal, so we have to stop
exercising, so we get even more susceptible to diseases. 但是，这不像你所想象的那么毫无希望。我们可以非常明确地说，丧失了精力和生机，那就就是杀死我们大多数人的原因（我指的大多数人是没有死于凶杀等的那些人）。它使我们对像流感这样的疾病降低了抵抗力，而在我们年轻时是可以易于抗击的。它使我们容易骨折（如果我们跌到），骨折了也需要更长时间才能愈合，这样，我们不得不停止运动，这样，我们就更加容易生病。 It slows our
reactions, so that when we slip on the stairs we can't catch ourselves, so we
fall, etc. So actually, aging and death are more closely linked than they might
be. People who are physically robust are not likely to die any time soon;
people who are physically frail are more likely to die soon. 它使我们的反应迟缓，以至于当我们在楼梯上滑了一下，我们把持不住自己，所以滚了下来，等等。所以，实际上老化和死亡比想像的的还要紧密相关。精力充沛的人们无论如何不会马上就死；年老体衰的人们马上就死的可能性较大。 There are two
consequences of this. One is that the goal that a lot of biogerontologists (who
should know better) advocate as the ultimate purpose of their work is totally
impossible (even if it were desirable, which is unclear). That goal is often
called "compression of morbidity", and what it means is a shortening
of the average length of time that people spend in a frail state before they
die. 这有两个后果。一是目标：很多生物老年学家（他们应当知道得更多）倡言，作为他们研究工作的最终目标是完全不可能实现的（想要，但不知道怎样要）。那目标常常被称为“病态压缩”，它的意思是：在人们死亡前他们处在虚弱状态的平均时间长度被缩短了。 The idea is
that we should not be trying to extend total lifespan, only healthy lifespan
("healthspan"). As you can see, the only way to do that is to limit
access to medical care for things that people tend to die suddenly of, such as
heart failure, so that fewer of us die of lingering diseases like cancer. And
society, surprise surprise, seems dubious about that strategy -- or, indeed,
any other strategy that shortens people's average total lifespan. 有一个观点：我们不必扩展整体寿命，只要健康寿命（“健寿”）。如你可以看到的，要做这件事的唯一途径是，限制如心脏衰竭这样的医学照料，使人们突然死光，以至于我们的很少人能死于像癌症这样的迁延性疾病。社会似乎不接受那个策略 — 或者，说实在的，似乎也不接受会缩短人们平均整体寿命的任何其它策略，感到奇怪吧。 The other
consequence of the tight biological linkage between aging and death is that we can measure our ability to combat aging by
observing our impact on death rates, and this is where I (finally!) get to
explain the basis for the term "Engineered Negligible Senescence". 老化和死亡紧密生物学联系的另一个后果是，我们可以测量与老化战斗的能力：观察我们对死亡速率的影响，这就是我（最终！）要解释“掌控可忽略衰老”的基础。 Let's start at
the end, with "senescence". This is a term that many
biogerontologists have used for a very long time, and informally what they mean
by it is the progressive loss of physical robustness that happens with time.
But because of the linkage between aging and death, they have also been able to
give "senescence" a formal, mathematical definition -- the
progressive increase in an organism's likelihood to die soon. 让我们以“衰老”来作结尾。这是很多生物老年学家用了很长时间的一个术语，他们非正式地使用“衰老”一词的含义是：充沛的体力随时间而前进性丧失。但因为老化与死亡之间的联系，他们也曾经能给“衰老”以一个正式的、数学性的定义 — 一个有机体很快死亡的可能性的前进性增加。 This is
something that can be measured. It can't be measured on a single individual,
because single individuals only die once and that single event doesn't give
much information about how likely the person was to die at any prior time (or,
indeed, at any later time if they hadn't died when they did). But if we look at
a population of people (or other organisms, for that matter), we have a lot of
information -- the age at death of each individual -- and we can use that to
estimate the probability of death. 这是可测量的某种东西。它可以在一个个体上测量，因为一个个体只死一次，但该单个事件并不提供很多信息 — 关于那个人任何此前将死的可能性（或者说任何此后将死的可能性，如果当他们将死而未死）。但如果我们着眼于一个人群（或其它有机体，目的相同），那么我们就会有关于每一个个体死亡年龄的很多信息，我们可以用之估计死亡的或然率。
In particular,
we can use it to relate the probability of death to other characteristics of the
individuals, such as their diet, their gender -- or their age. This is what
gerontologists have done: they have defined the term "senescence" to
mean a positive correlation between age and risk of death in the coming short
time period (typically a year for humans). 特别是，我们可以用它把死亡或然率与个体其它特征（如他们的食物、性别或年龄）联系起来。这是老年学家已经做的事情：他们已经把“衰老”这一术语定义为年龄与即将到来的短时期（在典型情况下，人类为一年）的死亡风险正相关。 To see what
this means in practical terms, think about radioactivity. We can talk about the
half-life of a radioactive isotope, and indeed we can measure and state very
very precisely what that half-life is. We do this by measuring the distribution
of time of decay -- "death" -- of individual atoms in a sample of the
isotope. And the point is, that half-life stays the same forever, even though
atoms are decaying all the time. 瞧瞧在实用术语中它意味着什么，请想想放射性。我们可以谈论放射性同位素的半衰期，我们确实可以非常准确地测量和描述半衰期是什么。我们可以办到这一点，方法是测量该同位素一个样品的各个原子衰减的时间分布（“死亡”）。重点是，半衰期永远是一样的，即使原子一直在衰减。 Each
individual atom retains the exact same probability of decaying in the next hour
(or second, or year -- it doesn't matter what unit of time you look at) as it
had before, right up until the moment that it actually decays. In the language
of biogerontology, radioactive atoms die but they don't senesce. People, on the
other hand, do senesce, because the probability of a 70-year-old dying in the
next year is higher than the probability of a 60-year-old dying in the next
year. 在下一个小时（或者下一秒或下一年，你要什么时间单位，那没关系），每个原子仍然保持准确的同样衰减或然性，如同它以前一样，如此一般，直到它实际上衰亡的那一刻。用生物老年学家的话说，放射性原子死亡了，但是它们并没有衰老。另一方面，人们却实实在在衰老，因为在下一年度，70岁老人死亡的可能性高于60岁老人。 But hang on --
how do we know that radioactive atoms don't senesce? There are, after all, only
a finite number of atoms in the sample that we measure the decay of -- a very
large number, but still it's finite. So in fact, if they senesce just a tiny
tiny bit over time -- that is, if their half-life gets shorter, very very
slowly -- we wouldn't actually be able to tell that this was happening in the
time that we took our measurements, because the acceleration in the rate of
atoms decaying (relative, of course, to the number that had not decayed
already, which is always decreasing) would be too tiny to be statistically
detectable. 但是，听清楚了 — 我们怎么知道放射性原子不衰老？归根结底，我们测量衰减的样品中只有很有限数目的原子 — 数目很多，但仍然是有限的。所以在事实上，如果它们随时间衰老得只那么一点点， — 就是说，如果它们的半衰期缩短得非常慢 — 那么我们实际上不可能知道，在我们测量期间发生过衰减，因为原子衰减的速率加速得太小，统计学上检测不出（当然，是相对于不曾衰减的数目而言，不曾衰减的原子数目总是在减少）。 With finite
numbers of events, we are always only able to say things with confidence if we
restrict ourselves to talking about possible ranges in which a rate might fall.
So here, we can only say that there is a range of possible rates of senescence
of the radioactive sample, and if there is a really tiny rate of senescence,
that range would still include zero. 因为事件的数目有限，如果我们只谈论一个速率可能坐落于可能的范畴，那么我们只能自信地就事论事。所以，在这里，我们只能说，放射性样品衰老可能的速率有一个范围，如果有一个衰老的真正极小速率，那么该范围仍然应当包括零。
This is not
very interesting in radioactivity, because the number of atoms we look at is
usually so huge that for practical purposes we can forget about the possibility
of half-lifes getting shorter. But in gerontology it matters a lot, because the
number of people (or animals) that we can look at the ages at death of is
relatively small. This was recognised some time ago, especially by a very
eminent and innovative gerontologist named Caleb Finch. 这在放射性方面不是很有意义，因为我们所观察的原子数目通常很大，以至于在实用上我们可以忘记半衰期变短的可能性。但是，在老年学中，它就要紧得多，因为我们所观察的死光年龄的人类（或动物）数目是相对小的。这一点在某时以前被认识到了，特别是被杰出的、富有创新精神的老年学家Caleb Finch所认识到。 He introduced
the term "negligible senescence" to mean "senescence too slight
to be statistically distinguishable from zero with the sample sizes at our
disposal". That includes non-senescence, of course -- truly zero
correlation between age and risk of death -- but the point was that it
encapsulated the experimental and observational reality that if we found a
genuinely non-senescing organism, we could never truly know that we had done
so. (Indeed, most biogerontologists believe that some organisms, even some very
primitive animals, are non-senescing, but they can't prove it, and Finch made
this explicit.) 他引进“可忽略衰老”这一术语来描述“衰老太微小，以至于以我们处理的样品体积来说在统计学上与零难以区别”的程度。当然，它包括不衰老（年龄与死亡风险之间的真正零关系），但是，重要的是，它把实验的和观察的真实存在隐藏了起来，使得我们若真的发现了一个不衰老有机体，我们也不能真的知道发现了它。（诚然，大多数生物老年学家相信，某些有机体
— 即使某些非常原始的动物 — 是不衰老的，但他们不能证明它，Finch直截了当地说出了这一点）。 Biogerontologists
like the term "negligible senescence" for exactly this reason -- as
scientists, they like to say what they know and no more. This of course means
that they immediately understand the term "engineered negligible
senescence" -- the biotechnological conversion of a population that shows
senescence (humans, of course) into one that does not. 生物老年学家喜欢“可忽略衰老”这一术语，正是因为作为科学家，他们喜欢说他们所知道的，其它的一切免谈。这当然意味着，他们能马上就能理解术语“掌控可忽略衰老”这一术语
— 把一个会出现衰老的群体（当然是人类）用生物技术方法转化为不出现衰老的群体。 So that's why
I have chosen to use the term "engineered negligible senescence"
(ENS) to describe what I want to help develop, and why my work is therefore
best described as the development of strategies for ENS, or SENS. I'm a
biogerontologist myself, after all -- and, never forget, I consider my fellow
biogerontologists to be my most important audience, because they are so
influential in determining what science is done, as I explain here. 所以，那就是为什么我选择利用术语“掌控可忽略衰老”（ENS）来描述我要帮助发展什么，而因此，我的工作最好被描述为发展ENS（或SENS）的策略。我自己是一位生物老年学家，归根结底，不要忘记，我把我的同行生物老年学家视为我的非常重要的听众，因为他们在决定科学项目方面太有影响力了，正如我在在这里（here）所解释的。
If every
expert in the biology of aging agreed with me about the foreseeability of ENS,
my job would be essentially done: public opinion would fall in behind the
scientists (as it always does), the political weight would fall in behind
public opinion (as it always does), and the research and development would
proceed as fast as possible, with no financial obstacles whatsoever. So I like
to use a term that my colleagues in biogerontology understand well and are
comfortable with, even if it may be a bit of a mouthful. 如果衰老生物学每一位专家在关于ENS的预测性方面都赞成我，那么我的工作将进行得很顺利：公众的意见取决于科学家（一向如此），政治的份量取决于公众意见（一向如此），这样，没有了任何财政上的障碍，研究和开发将尽可能快地进行。所以，我喜欢使用一个术语，这个术语能使我的生物老年学同行既好理解，又感到舒服，即使这个术语有点拗口。 Problems or
questions regarding this site should be directed to Dr. de Grey 有关本网站的问题和询问一律由Dr. de Grey 主持。 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||