治疗蛀牙的新方法

鲨鱼一生中都会长出新牙齿，而成年人只有一副牙，必须保持60年或更长时间。

双语精读

The human body is a marvellous thing. But like anything built by evolution, it has plenty of flaws.

人体是一种神奇的东西。但和所有进化而来的东西一样，它也有很多缺陷。

Consider teeth. Whereas sharks grow new teeth throughout their lives, adult humans get one set, which must last 60 years or more. That is tricky.

想一想牙齿。鲨鱼一生中都会长出新牙齿，而成年人只有一副牙，必须保持60年或更长时间。这就很难办。

A combination of poverty, sugar-rich diets and poor hygiene means 2.5bn people around the world suffer from tooth decay, in which acid produced by mouth-dwelling bacteria eats away at the hard enamel that coats the outside of a tooth.

贫困、高糖饮食，再加上卫生条件差，使得全球有25亿人患有蛀牙。蛀牙是指口腔中的细菌产生的酸侵蚀了覆盖在牙齿外部的坚硬牙釉质。

That can open the door to painful infections, which cause further damage. Once decay has set in, all a dentist can do is fill the gap with an artificial plug-a filling.

这可能会导致令人痛苦的感染，从而进一步损害牙齿。蛀牙一旦发生，牙医所能做的就只是用人造的堵塞物（填料）填满空隙。

But in a paper published in Cell, Hannele Ruohola-Baker, a stem-cell biologist at the University of Washington, and her colleagues offer a possible alternative.

但是在《细胞》期刊上发表的一篇论文中，华盛顿大学的干细胞生物学家汉内莱·罗霍拉-贝克及其同事提供了另一种可能的治疗办法。

Stem cells are those that have the capacity to turn themselves into any other type of cell in the body. It may soon be possible, the researchers argue, to use those protean cells to regrow a tooth's enamel naturally.

干细胞是能够将自己转化为体内任何其他类型细胞的细胞。研究人员认为，很快就有可能利用这些能千变万化的细胞自然地再生牙釉质了。

The first step was to work out exactly how enamel is produced. That is tricky, because enamel-making cells, known as ameloblasts, disappear soon after a person's adult teeth have finished growing.

第一步是弄清楚牙釉质如何产生。这是一个棘手的问题，因为牙釉质生成细胞，即成釉细胞，在人的成年牙齿生长完成后很快就会消失。

To get round that problem, the researchers turned to samples of tissue from human foetuses that had been aborted, either medically or naturally. Such tissues contain plenty of functioning ameloblasts.

为了解决这个问题，研究人员转而使用从人工流产或自然流产的人类胎儿中提取的组织样本。这些组织含有大量的功能正常的成釉细胞。

The researchers then checked to see which genes were especially active in the enamel-producing cells. Tooth enamel is made mostly of calcium phosphate, and genes that code for proteins designed to bind to calcium were particularly busy.

然后，研究人员核对了哪些基因在产生牙釉质的细胞中特别活跃。牙釉质主要是由磷酸钙构成的，而给用于与钙结合的蛋白质编码的基因特别忙碌。

They also assessed another type of cell called odontoblasts. These express genes that produce dentine, another type of hard tissue that lies beneath the outer enamel.

研究人员还评估了另一种被称为成牙细胞的细胞。这些细胞表现了产生牙本质的基因性状，牙本质是位于外层的牙釉质下面的另一种坚硬组织。

Armed with that information, Dr Ruohola-Baker and her colleagues next checked to see whether the stem cells could be persuaded to transform into ameloblasts.

有了这些信息，罗霍拉-贝克博士和她的同事们下一步核验了是否可以引导干细胞转变成成釉细胞。

The team devised a cocktail of drugs designed to activate the genes that they knew were expressed in functioning ameloblasts. That did the trick, with the engineered ameloblasts turning out the same proteins as the natural sort.

该团队设计了一种混合药物，用于激活他们知道能在正常成釉细胞中表现出来的基因。这一招奏效了，改造的成釉细胞产生了与天然成釉细胞相同的蛋白质。

A different cocktail pushed the stem cells to become odontoblasts instead. Culturing the cells together produced what researchers call an organoid-a glob of tissue in a petri dish which mimics a biological organ.

而另一种混合药物则促使干细胞分化为成牙细胞。将这些细胞一起培养，就产生了研究人员所说的类器官——一种在培养皿中培养的模仿生物器官的组织团。

The organoids happily churned out the chemical components of enamel. For now, the work is more a proof of concept than a prototype of an imminent medical treatment.

类器官顺利地分泌出了许多牙釉质的化学成分。目前，这项工作更多的是证明了这个概念可行，而不是给即将到来的医学治疗提供了原型。

The next step, says Dr Ruohola-Baker, is to try to boost enamel production even further, with a view to eventually beginning clinical trials.

罗霍拉-贝克博士说，下一阶段是进一步促进牙釉质的产生，希望最终能开始临床试验。

词汇预习

particularly [高考]
美[pərˈtɪkjələrli] | 英[pəˈtɪkjələli]
adv. 特别；尤其；详细地
code [高考]
美[koʊd] | 英[kəʊd]
n. 密码；法规；准则 v. 制成法典；把 ... 编码
biological [高考]
美[ˌbaɪəˈlɑːdʒɪkl] | 英[ˌbaɪəˈlɒdʒɪkl]
adj. 生物的；生物学的
combination [高考]
美[ˌkɑːmbɪˈneɪʃn] | 英[ˌkɒmbɪˈneɪʃn]
n. 结合；结合到一起的事物或人；数码组合，字码组合
poverty [高考]
美[ˈpɑːvərti] | 英[ˈpɒvəti]
n. 贫困；贫乏；劣质
capacity [高考]
美[kəˈpæsəti] | 英[kəˈpæsəti]
n. 容量；容积；能力；职位；资格
biologist [高考]
美[baɪˈɑːlədʒɪst] | 英[baɪˈɒlədʒɪst]
n. 生物学家
stem [高考]
美[stem] | 英[stem]
n. 柄；茎；干；船首 vi. 起源于 vt. 抽去 ... 的梗；给 ... 装柄；逆 ... 而行；阻止，遏制
tricky [高考]
美[ˈtrɪki] | 英[ˈtrɪki]
adj. 棘手的；狡猾的；巧妙的
proof [高考]
美[pruːf] | 英[pruːf]
n. 证明; 检验; 证据 adj. 防/抗…的; 能抵御 v. 使防水（或防火等）; 印…的校样; 校对
calcium [高考]
美[ˈkælsiəm] | 英[ˈkælsiəm]
n. 钙
decay [高考]
美[dɪˈkeɪ] | 英[dɪˈkeɪ]
v. (使)衰退；(使)腐败；(使)腐烂 n. 衰退；腐烂；腐败
activate [高考]
美[ˈæktɪveɪt] | 英[ˈæktɪveɪt]
v. 激活；使活动；起动
boost [高考]
美[buːst] | 英[buːst]
v. 提高；增加；鼓励；举起；为...做宣传 n. 增加；推进；鼓励
eventually [高考]
美[ɪˈventʃuəli] | 英[ɪˈventʃuəli]
adv. 最后；终于
contain [高考]
美[kənˈteɪn] | 英[kənˈteɪn]
vt. 容纳；包含；抑制；克制 vi. 自制
concept [高考]
美[ˈkɑːnsept] | 英[ˈkɒnsept]
n. 观念；概念；想法
alternative [高考]
美[ɔːlˈtɜːrnətɪv] | 英[ɔːlˈtɜːnətɪv]
adj. 两者择一的；供选择的；非主流的 n. 二者择一；供替代的选择
artificial [高考]
美[ˌɑːrtɪˈfɪʃl] | 英[ˌɑːtɪˈfɪʃl]
adj. 人造的；虚伪的；武断的
beneath [高考]
美[bɪˈniːθ] | 英[bɪˈniːθ]
prep. 在 ... 之下；被...覆盖；低于...；不值得 adv. 在下方；在底下
transform [高考]
美[trænsˈfɔːrm] | 英[trænsˈfɔːm]
v. 使改观，使变形，使转化；变换（电流）的电压；（数）变换（数学实体） n.（数，语言学）变换式，转换句；（数，语言学）转换规则
evolution [高考]
美[ˌevəˈluːʃn] | 英[ˌiːvəˈluːʃn , ˌevəˈluːʃn]
n. 进化；发展；演变
outer [高考]
美[ˈaʊtər] | 英[ˈaʊtə(r)]
adj. 外部的；外面的
tissue [高考]
美[ˈtɪʃuː] | 英[ˈtɪʃuː]
n. 纸巾；薄绢；(生物的)组织；织物
organ [高考]
美[ˈɔːrɡən] | 英[ˈɔːɡən]
n. 器官；风琴；机构；喉舌；报刊
acid [高考]
美[ˈæsɪd] | 英[ˈæsɪd]
adj.酸味的;尖刻的;酸的;酸性的 n.[化]酸;酸味物质
set in [高考]
美[sɛt ɪn] | 英[set in]
嵌入；开始
means [高考]
美[miːnz] | 英[miːnz]
n. 方法；手段；收入；财产 v. 意思是，意味（动词mean的第三人称单数）
further [高考]
美[ˈfɜːrðər] | 英[ˈfɜːðə(r)]
adv. 更远地，再往前地；进一步；此外，而且 adj. 更多的，进一步的；（距离上）更远的，较远的 v. 促进，推进
gap [高考]
美[ɡæp] | 英[ɡæp]
n. 缺口；裂缝；差距；空白
plug [高考]
美[plʌɡ] | 英[plʌɡ]
n.插头；塞子；栓塞；插座 v.堵塞；封堵；补足；补充
bind [高考]
美[baɪnd] | 英[baɪnd]
v. 捆绑；装订；约束；强迫；团结 n. 窘境
marvellous [高考]
美[ˈmɑːrvələs] | 英[ˈmɑːvələs]
adj. 惊奇的；非凡的；绝妙的
turning [高考]
美[ˈtɜːrnɪŋ] | 英[ˈtɜːnɪŋ]
n. 旋转；回转；转向
clinical [四级]
美[ˈklɪnɪkl] | 英[ˈklɪnɪkl]
adj. 临床的；冷静的
happily [四级]
美[ˈhæpɪli] | 英[ˈhæpɪli]
adv. 幸福地；快乐地；幸好；恰当地
hygiene [六级]
美[ˈhaɪdʒiːn] | 英[ˈhaɪdʒiːn]
n. 卫生；卫生学
prototype [六级]
美[ˈproʊtətaɪp] | 英[ˈprəʊtətaɪp]
n. 原型；范例；雏形
dwelling [专四]
美[ˈdwelɪŋ] | 英[ˈdwelɪŋ]
n. 住处；住宅
imminent [专四]
美[ˈɪmɪnənt] | 英[ˈɪmɪnənt]
adj. 逼近的；即将发生的
enamel [专八]
美[ɪˈnæməl] | 英[ɪˈnæml]
n. 搪瓷；珐琅；瓷釉 v. 涂以瓷釉
cocktail [考研]
美[ˈkɑːkteɪl] | 英[ˈkɒkteɪl]
n. 鸡尾酒；混合物；开胃品 n. 截短尾巴的马 adj. 鸡尾酒的
checked [托福]
美[tʃɛkt] | 英[tʃekt]
adj. 格子花纹的；棋盘花纹的 v. 检查；阻止；核对（动词check的过去式和过去分词）

重点讲解

The human body is a marvellous thing. But like anything built by evolution, it has plenty of flaws.

人体是一种神奇的东西。但和所有进化而来的东西一样，它也有很多缺陷。

marvellous adj. 神奇的；极好的

【例】The modern technology is marvellous.

现代科技非常了不起。

The weather was marvellous.

天气好极了。

【拓展】marvel at sth 对某事感到惊叹

set n. 一套东西；一群人

【例】a complete set of Harry Potter books/the Harry Potter book set

《哈利·波特》全套书

a set of false teeth 一副假牙

the tech set in Silicon Valley 硅谷的科技咖们

Consider teeth. Whereas sharks grow new teeth throughout their lives, adult humans get one set, which must last 60 years or more. That is tricky.

想一想牙齿。鲨鱼一生中都会长出新牙齿，而成年人只有一副牙，必须保持60年或更长时间。这就很难办。

marvellous adj. 神奇的；极好的

【例】The modern technology is marvellous.

现代科技非常了不起。

The weather was marvellous.

天气好极了。

【拓展】marvel at sth 对某事感到惊叹

set n. 一套东西；一群人

【例】a complete set of Harry Potter books/the Harry Potter book set

《哈利·波特》全套书

a set of false teeth 一副假牙

the tech set in Silicon Valley 硅谷的科技咖们

A combination of poverty, sugar-rich diets and poor hygiene means 2.5bn people around the world suffer from tooth decay, in which acid produced by mouth-dwelling bacteria eats away at the hard enamel that coats the outside of a tooth.

贫困、高糖饮食，再加上卫生条件差，使得全球有25亿人患有蛀牙。蛀牙是指口腔中的细菌产生的酸侵蚀了覆盖在牙齿外部的坚硬牙釉质。

hygiene n. 卫生
【例】personal hygiene 个人卫生

【拓展】hygienic adj. 卫生的

【近义词】sanitation n. 公共卫生；卫生设备

【例】to improve sanitation in rural areas 改善农村地区的卫生条件

tooth decay 蛀牙

【例】Regular brushing and flossing can significantly reduce the risk of tooth decay.

勤刷牙、勤用压线可以有效减少蛀牙风险。

【拓展】gum/tooth removal/have a tooth pulled/wisdom tooth

牙龈/拔牙/去拔牙/智齿

set in 开始（并可能持续存在）

【例】The rain set in early in the morning and didn't stop all day.

雨从清晨开始下，整天都没有停。

That can open the door to painful infections, which cause further damage. Once decay has set in, all a dentist can do is fill the gap with an artificial plug—a filling.

这可能会导致令人痛苦的感染，从而进一步损害牙齿。蛀牙一旦发生，牙医所能做的就只是用人造的堵塞物（填料）填满空隙。

hygiene n. 卫生
【例】personal hygiene 个人卫生

【拓展】hygienic adj. 卫生的

【近义词】sanitation n. 公共卫生；卫生设备

【例】to improve sanitation in rural areas 改善农村地区的卫生条件

tooth decay 蛀牙

【例】Regular brushing and flossing can significantly reduce the risk of tooth decay.

勤刷牙、勤用压线可以有效减少蛀牙风险。

【拓展】gum/tooth removal/have a tooth pulled/wisdom tooth

牙龈/拔牙/去拔牙/智齿

set in 开始（并可能持续存在）

【例】The rain set in early in the morning and didn't stop all day.

雨从清晨开始下，整天都没有停。

But in a paper published in Cell, Hannele Ruohola-Baker, a stem-cell biologist at the University of Washington, and her colleagues offer a possible alternative.

但是在《细胞》期刊上发表的一篇论文中，华盛顿大学的干细胞生物学家汉内莱·罗霍拉-贝克及其同事提供了另一种可能的治疗办法。

protean adj. 变化多端的；能千变万化的

【例】a protean character 多变的性格

a protean actor 戏路很宽的演员

【拓展】Proteus 海神普罗透斯

Stem cells are those that have the capacity to turn themselves into any other type of cell in the body. It may soon be possible, the researchers argue, to use those protean cells to regrow a tooth’s enamel naturally.

干细胞是能够将自己转化为体内任何其他类型细胞的细胞。研究人员认为，很快就有可能利用这些能千变万化的细胞自然地再生牙釉质了。

protean adj. 变化多端的；能千变万化的

【例】a protean character 多变的性格

a protean actor 戏路很宽的演员

【拓展】Proteus 海神普罗透斯

The first step was to work out exactly how enamel is produced. That is tricky, because enamel-making cells, known as ameloblasts, disappear soon after a person’s adult teeth have finished growing.

第一步是弄清楚牙釉质如何产生。这是一个棘手的问题，因为牙釉质生成细胞，即成釉细胞，在人的成年牙齿生长完成后很快就会消失。

get round

1. 解决；克服

【例】We need to get round the funding issue.

我们需要解决资金问题。

2. 说服；劝说

【例】I managed to get round my parents to let me go on the school trip.

我设法说服了爸妈让我参加学校的旅行。

abort v. 流产；中止

【例】abort the child 流产

abort the mission 中止任务

To get round that problem, the researchers turned to samples of tissue from human foetuses that had been aborted, either medically or naturally. Such tissues contain plenty of functioning ameloblasts.

为了解决这个问题，研究人员转而使用从人工流产或自然流产的人类胎儿中提取的组织样本。这些组织含有大量的功能正常的成釉细胞。

get round

1. 解决；克服

【例】We need to get round the funding issue.

我们需要解决资金问题。

2. 说服；劝说

【例】I managed to get round my parents to let me go on the school trip.

我设法说服了爸妈让我参加学校的旅行。

abort v. 流产；中止

【例】abort the child 流产

abort the mission 中止任务

然后，研究人员核对了哪些基因在产生牙釉质的细胞中特别活跃。牙釉质主要是由磷酸钙构成的，而给用于与钙结合的蛋白质编码的基因特别忙碌。

bind v. 结合；使结合

【例】to bind the broken pieces to each other

把碎片粘起来

oxygen molecules bind to hemoglobin in the blood

氧分子与血液中的血红蛋白结合

They also assessed another type of cell called odontoblasts. These express genes that produce dentine, another type of hard tissue that lies beneath the outer enamel.

研究人员还评估了另一种被称为成牙细胞的细胞。这些细胞表现了产生牙本质的基因性状，牙本质是位于外层的牙釉质下面的另一种坚硬组织。

bind v. 结合；使结合

【例】to bind the broken pieces to each other

把碎片粘起来

oxygen molecules bind to hemoglobin in the blood

氧分子与血液中的血红蛋白结合

Armed with that information, Dr Ruohola-Baker and her colleagues next checked to see whether the stem cells could be persuaded to transform into ameloblasts.

有了这些信息，罗霍拉-贝克博士和她的同事们下一步核验了是否可以引导干细胞转变成成釉细胞。

be armed with sth 配有某物

【例】be armed with a gun 带有一支枪

We are armed with all the necessary resources.

该有的资源我们都备齐了。

【近义词】be equipped with 装备；使有某种能力

该团队设计了一种混合药物，用于激活他们知道能在正常成釉细胞中表现出来的基因。这一招奏效了，改造的成釉细胞产生了与天然成釉细胞相同的蛋白质。

be armed with sth 配有某物

【例】be armed with a gun 带有一支枪

We are armed with all the necessary resources.

该有的资源我们都备齐了。

【近义词】be equipped with 装备；使有某种能力

A different cocktail pushed the stem cells to become odontoblasts instead. Culturing the cells together produced what researchers call an organoid—a glob of tissue in a petri dish which mimics a biological organ.

而另一种混合药物则促使干细胞分化为成牙细胞。将这些细胞一起培养，就产生了研究人员所说的类器官——一种在培养皿中培养的模仿生物器官的组织团。

culture v. 培养（细胞或病菌）

【例】to culture the bacteria 培养细菌

culture medium 培养基

imminent adj. 即将发生的；临近的

【例】the imminent threat 迫在眉睫的威胁

【辨析】immediate adj. 目前的；紧接着的

【例】the immediate danger/future

当下面临的危险/短期内

with a view to 目的是；预期结果是

【例】She took the course with a view to changing her career path.

她参加了这个课程，目的是想改变她的职业道路。

The organoids happily churned out the chemical components of enamel. For now, the work is more a proof of concept than a prototype of an imminent medical treatment.

类器官顺利地分泌出了许多牙釉质的化学成分。目前，这项工作更多的是证明了这个概念可行，而不是给即将到来的医学治疗提供了原型。

culture v. 培养（细胞或病菌）

【例】to culture the bacteria 培养细菌

culture medium 培养基

imminent adj. 即将发生的；临近的

【例】the imminent threat 迫在眉睫的威胁

【辨析】immediate adj. 目前的；紧接着的

【例】the immediate danger/future

当下面临的危险/短期内

with a view to 目的是；预期结果是

【例】She took the course with a view to changing her career path.

她参加了这个课程，目的是想改变她的职业道路。

The next step, says Dr Ruohola-Baker, is to try to boost enamel production even further, with a view to eventually beginning clinical trials.

罗霍拉-贝克博士说，下一阶段是进一步促进牙釉质的产生，希望最终能开始临床试验。

culture v. 培养（细胞或病菌）

【例】to culture the bacteria 培养细菌

culture medium 培养基

imminent adj. 即将发生的；临近的

【例】the imminent threat 迫在眉睫的威胁

【辨析】immediate adj. 目前的；紧接着的

【例】the immediate danger/future

当下面临的危险/短期内

with a view to 目的是；预期结果是

【例】She took the course with a view to changing her career path.

她参加了这个课程，目的是想改变她的职业道路。

课后练习

According to the author, what is the flaw in human teeth?
A. Human teeth are not as sharp as those of sharks.
B. Tooth decay is common and cannot be prevented.
C. Human teeth fall out once people reach the age of 60.
D. Adults cannot grow new teeth to replace the bad ones.
What alternative solution do Ruohola-Baker suggest to tooth decay?
A. Preventing enamel-making cells from disappearing.
B. Turning stem cells into the cell that generates enamel.
C. Developing a new type of artificial plug to fill the gaps in teeth.
D. Transplanting ameloblasts from foetuses into the human body.
What role do the most active genes in enamel-producing cells play?
A. They stimulate the growth of new teeth in adults.
B. They create calcium phosphate to protect teeth.
C. They produce dentine beneath the enamel.
D. They code for proteins that are crucial for making enamel.
What kind of result did the researchers achieve?
A. Some tissue that can function like enamel-producing cells.
B. A biological organ that can create ameloblasts.
C. A special protein that can make enamel.
D. The prototype of a new medical treatment.