ADM-201 dump PMP dumps pdf SSCP exam materials CBAP exam sample questions

独眼畸形:罕见的出生缺陷可以帮助治愈癌症 – 译学馆
未登陆,请登陆后再发表信息
最新评论 (0)
播放视频

独眼畸形:罕见的出生缺陷可以帮助治愈癌症

Cyclopia: A Rare Birth Defect That Could Help Cure Cancer

我们一谈到神秘的独眼怪物
When it comes to mythical one-eyed creatures,
第一个想到的可能就是库克罗普斯
the first thing you think of is probably the Cyclops.
当然其他传说里也有许多这样的生物
There are also lots of other legendary creatures to choose from, too,
从只要睁开双眼就会带来毁灭的爱尔兰神巴罗尔
from the Irish god Balor, who only opens his eye to bring destruction,
到最不具有威胁的日本独眼小僧
to the mostly harmless Hitotsume-kozō of Japan.
在自然界 生物通常都拥有两只眼睛
In nature, on the other hand, eyes pretty much always come in twos, and there’s no
还没有哪种脊椎动物进化成了独眼生物
vertebrate species that evolved to have one eye.
即便如此 如果胚胎在发育期间出现失误
That said, if something goes wrong during its development as an embryo,
任何脊椎动物都会产生我们所称的独眼畸形
any vertebrate can develop what’s known as cyclopia,
“独眼畸形”取名于那些传说中一只眼睛的生物
a condition named after those one-eyed creatures of legend.
它是一种毁灭性的并发症 通常是致命的
It’s a devastating complication, and generally fatal.
但研究这种病症 却可能会帮助调查人员找到治疗某些癌症的新方法
But studying it might help researchers discover new ways to treat certain types of cancers.
大多数关于真实的独眼动物报告
Most of the reports you’ll find about real cyclopic animals
都是通过互联网传播开来的
were spread through the internet,
关于独眼小羊 山羊 鲨鱼和人类的报导已屡见不鲜
but news of cyclops lambs, goats, sharks, and humans is nothing new.
你甚至可以发现一头出生就患有独眼畸形的猪的准确描述
There’s even a fairly accurate description of a pig born with cyclopia
这可以追溯到1642年美国康乃狄克州殖民时期
that dates back to a Connecticut colony in 1642.
所以正常有两只眼睛的动物
So how does an animal that normally has two eyes
是怎样发展成在它脸的中间只有一只眼睛的?
develop only one in the center of its face?
纽黑文殖民者声称死胎小猪是人兽性交的产物
The New Haven colonists claimed that their stillborn piglet was the product of bestiality,
可他们错了 而且是大错特错
but they were wrong … very wrong.
产生这结果的原因跟大脑发育过程有关
It all has to do with how the brain develops.
脊椎动物胚胎形成期 大脑分为三个部分:后脑
In a developing vertebrate embryo, the brain consists of three regions: the hindbrain,
中脑 前脑
the midbrain, and the forebrain.
前脑最终会分化成两个部分:
The forebrain eventually differentiates into two parts:
间脑 它会变成大脑的内部区比如丘脑和下丘脑
the diencephalon, which becomes inner parts of the brain like the thalamus and the hypothalamus
以及端脑 它会演变成大脑
and the telencephalon, which turns into the cerebrum.
对人类来说 这个过程大概会发生在孕期4或5周
In humans, this happens around week 4 or 5 of gestation.
但是 前脑有时并不会完全分开
But sometimes, the forebrain doesn’t completely split,
这阻碍了大脑许多重要结构的形成
which hinders the development of a lot of important brain structures,
包括大脑左右半球
including the left and right hemispheres.
这种情况叫做前脑无裂畸形 或简称为HPE
The condition is called holoprosencephaly, or HPE,
它的严重程度取决于
and it can vary in severity depending on
大脑发育被影响的严重程度
how much of the brain’s development is affected.
独眼畸形基本上是HPE里最罕见及最严重的变形
Cyclopia is basically the rarest and most severe form of HPE,
它根据其最显著的副作用而得名:
and it’s named after its most noticeable side effect:
脸部中央只有一只眼睛
a single ocular tract in the center of the face.
通常 胚胎还会在眼睛上面长出一个鼻子
Embryos also usually develop a proboscis positioned above the eye
不同案例中 可能也会表现出其他种类的严重生理缺陷
and they tend to have other severe physical defects that differ from case to case.
人类很少出现独眼畸形:
In humans, cyclopia is rare:
据估计 每10万的新生儿中也大概只有一例
it’s found in an estimated 1 in 100,000 births,
但不幸的是 这1例就是致命的
although unfortunately, it’s always fatal.
患有轻微的HPE的人比较常见
But the less severe forms of HPE are more common.
总体来说 250个胚胎里大约会有1个患HPE
Overall, HPE happens in about 1 in 250 conceptions
16000名新生儿中 会有一名得以存活
and 1 in 16,000 live births, and it can be survivable.
HPE非常普遍的部分原因是
Part of the reason HPE is so common is that
各种各样的因素都可以致使其产生
it can be caused by a lot of different factors,
从单基因突变 到一条染色体的多余复制体
from a single genetic mutation, to an extra copy of a chromosome
以及引起先天畸形的致畸剂
to teratogens, which are substances that cause birth defects
如果发育中的胚胎接触到这些 就会导致这种畸形
when a developing embryo is exposed to them.
对于研究人员来说 掌握更多的病症起因很重要
For researchers, learning more about those causes is important
因为它可以帮助预防先天缺陷
because it can help prevent birth defects,
同时也在于 他们与某些诱发癌症的过程
but also because they have a lot in common with processes
具有很多相似性
that lead to certain kinds of cancer.
与前脑无裂畸形相关的一个主要基因
The main gene connected with HPE is called
叫做音猬因子 简称SHH
Sonic hedgehog, or SHH for short.
事实上 它跟传播速度快没什么关系
It doesn’t actually have anything to do with running really fast,
科学家如此命名 是因为在果蝇体内有相关的基因突变
but scientists named it that because there’s a related genetic mutation in fruit flies
使他们看起来像全身覆盖着体刺
that makes them look like they’re covered in spines.
科学家们就像是书呆子
And because scientists are nerds.
音猬因子的蛋白质代码 也叫作Shh
The protein SHH codes for, which is also called Shh,
它在胚胎发育过程中扮演着重要的角色
plays a crucial role in embryonic development
包括告诉前脑如何分化并组成半脑
including telling the forebrain how to differentiate and form hemispheres.
但是Shh蛋白质并不是单独工作
But the Shh protein doesn’t work alone.
它有些像授权的领导 其他蛋白质会听从听它的命令
It’s sort of a delegating boss, telling another protein to instruct
去指挥第三个蛋白质与细胞的DNA捆绑 以激活基因
a third protein to bind to a cell’s DNA to activate a gene,
这也就是Shh的信号传递路径
in what’s known as the Shh signaling pathway.
正因为这里面包含太多步了 很容易就出错
Since there are so many steps involved, there are a lot of ways things can go wrong.
如果胚胎接触到任何干扰这指令线路的合成物
If the embryo is exposed to any compound that interrupts this flow of instructions,
Shh就不能命令前脑中的细胞进行分化
Shh can’t tell cells in the forebrain to differentiate.
细胞一旦不知道如何分化 就会产生前脑无裂畸形
And if the cells don’t know to differentiate, that leads to HPE.
即使音猬因子是胚胎中重要的基因分子
Even though SHH is a really important gene in embryos,
但生命诞生后 它几乎会进入休眠状态
it’s mostly dormant after birth.
如果它被以某种方式激活了
But if it gets activated somehow,
就会引发不可控的细胞分裂 导致各种各样的癌症
it can cause uncontrolled cell division that leads to all kinds of cancers
从肺癌 胰腺癌 到皮肤癌
from lung to pancreatic to skin cancer.
胚胎时期 对Shh路径的干涉 可能会产生致命后果
In an embryo, interfering with the Shh pathway can be devastating.
结果导致前脑无裂畸形
It’s what leads to HPE.
但是要治疗这种因在不当情况下激活通道而导致的癌症
But to treat a cancer that’s caused by the pathway activating when it isn’t supposed to,
妨碍Shh通道恰恰是我们想要做的
interfering with it is exactly what you want to do.
1968年 调查人员发现有一种合成物堵住了Shh的移动路径
And in 1968, researchers discovered a compound that obstructs the Shh pathway,
这多亏了一群一直生育独眼羔羊的爱达荷绵羊
thanks to a population of Idaho sheep that kept giving birth to cyclopic lambs.
经过10多年的研究 科学家已经能将相关的化合物
After more than a decade of research, scientists were able to isolate the responsible compound
从加利福尼亚的鸢尾植物中分离出来
from the California corn lily.
他们将其命名为环巴胺
They named it cyclopamine.
放牧的时候 怀孕的母羊吃这种植物的话
Pregnant ewes ate the plants while grazing,
会让它们的后代出现各种各样的先天畸形
which caused their offspring to develop all kinds of birth defects.
实验测试表明 如果他们在孕期的第14天 摄入了这种环巴胺
Lab tests showed that if they ate the cyclopamine on the 14th day of gestation,
羊羔就会发展成独眼畸形
the lambs developed cyclopia.
所以现在 研究人员正在尝试利用
So now, researchers are trying to take advantage of
环巴胺紊乱Shh移动路径的方式来挽救生命
how cyclopamine disrupts the Shh pathway to save lives.
由于环巴胺是个复杂的分子 因此还需要一段时间的实验
It’s taking a while because cyclopamine is a complicated molecule,
制造或提取足量的环巴胺进行适当研究
and they’ve had a tough time figuring out how to either make or
已经很难
extract enough of it to study it properly.
想要制作出一个版本 可以被身体吸收利用
It’s been even harder to make a version that’s absorbed and used by the body,
从而有效地治疗癌症 更难上加难
in a way that would make it an effective cancer treatment.
但是他们一直在努力
But they’re working on it,
他们也在测试各种环巴胺及其他可以阻碍路径的化合物
and versions of cyclopamine and other compounds that disrupt that pathway
来对抗胰腺癌与皮肤癌
are being tested against things like pancreatic and skin cancer.
所以也许某天 畸形羔羊和罕见先天畸形的故事
So, someday, the story of some lambs and a rare birth defect
也许会挽救千千万万的生命
might save thousands of lives every year.
谢谢观看我们SciShow节目的视频
Thanks for watching this episode of SciShow.
如果你想了解更多关于癌症是怎样发病的 你可以收看我们的节目
If you’re interested in learning more about how cancer works, you can watch our video
它会帮你解答为什么我们现在还没有治愈癌症
about why we haven’t cured it yet
尽管我们已经投入了大量的时间和金钱在癌症研究上
even though there’s so much time and money being poured into cancer research.

发表评论

译制信息
视频概述

通过研究一种合成物质来干预Shh移动路径,人类很可能找到治愈癌症的办法

听录译者

收集自网络

翻译译者

喋喋

审核员

译学馆审核团D

视频来源

https://www.youtube.com/watch?v=r8jWAvF3rcE

相关推荐