Transcript 临床医学英语Unit 3

Unit 3
Gene Therapy
Word Formation
aden/o (gland) e.g. adenovirus
-ase (enzyme)
leuk/o (white) e.g. leukemia
syn- (together with) e.g. syndrome
poly- (multiple)
mono- (single) e.g. monocyte
homo- (the same) e.g. homograft homosexuality
chrom/o (colour) e.g. chromosome
-some (body) e.g. somatic
retr/o ( at the back, behind) e.g. retrovirus
path/o (illness) e.g. pathogen
-genic (produced by) e.g. pathogenic
lip/o (fat) e.g. liposome
auto- (self) e.g. autonomy, autonomously
tox/o (toxin) e.g. toxicity
arthr/o (joint) e.g. arthritis
fibr/o (fibre) e.g. fibrosis
Questions to consider:
1. What is a gene ?
2. What is gene therapy ?
3. Give your personal comment on gene therapy.
• What is a gene ?
the basic unit of genetic material, which is carried at
a particular place on a chromosome. Originally it was
regarded as the unit of inheritance and mutation but is
now usually defined as a sequence of DNA or RNA that
acts as the unit controlling the formation of a single
polypeptide chain.
What is gene therapy?
Gene therapy is an experimental technique that uses
genes to treat or prevent disease. In the future, this
technique may allow doctors to treat a disorder by
inserting a gene into a patient’s cells instead of using
drugs or surgery. Researchers are testing several
approaches to gene therapy, including:
• Replacing a mutated gene that causes disease with
a healthy copy of the gene.
• Inactivating, or “knocking out,” a mutated gene that
is functioning improperly.
• Introducing a new gene into the body to help fight a
disease.
Although gene therapy is a promising treatment option
for a number of diseases (including inherited disorders,
some types of cancer, and certain viral infections), the
technique remains risky and is still under study to make
sure that it will be safe and effective. Gene therapy is
currently only being tested for the treatment of diseases
that have no other cures.
Gene therapy is the introduction of genetic material
into cells for therapeutic purposes. Recent scientific
breakthroughs in the genomics field and our
understanding of the important role of genes in disease
has made gene therapy one of the most rapidly advancing
fields of biotechnology with great promise for treating
inherited and acquired diseases.
Many human diseases are caused by the absence or
inappropriate presence of a protein. Biotechnology's first
promise was to isolate and produce these natural proteins
through genetic engineering and recombinant technology.
The protein could then be administered to patients in
order to compensate for its absence. Because proteins are
not orally available, biotech companies focused on
innovative methods of protein delivery and sustained
drug delivery.
Today, gene therapy is the ultimate method of protein
delivery, in which the delivered gene enters the body's
cells and turns them into small "factories" that produce
a therapeutic protein for a specific disease over a
prolonged period.
As gene therapy has moved from the laboratory into the
clinic, several issues have emerged as central to the
development of this technology: gene identification, gene
expression and gene delivery.
• The types of gene therapy described thus far all have
one factor in common: that is, the tissues being
treated are somatic (somatic cells include all the cells
of the body, excluding sperm cells and egg cells). In
contrast to this is the replacement of defective genes in
the germline cells (which contribute to the genetic
heritage of the offspring).
• Gene therapy in germline cells has the potential to
affect not only the individual being treated, but also
his or her children as well. Germline therapy would
change the genetic pool of the entire human species,
and future generations would have to live with that
change. In addition to these ethical problems, a
number of technical difficulties would make it unlikely
that germline therapy would be tried on humans in the
near future.
Understanding the Text
Para. 1
• gene
• chromosome
• physical
• heredity
• sequences of bases
• encode / encoded
• genetic disorder
Para. 2
• defective/faulty genes
• nonspecific location
• a nonfunctional gene
• genome
• swap: to exchange 置换，交换， 掉换
e.g. I’d swap my job for hers any day.
我愿随时和她调换工作。
• homologous recombination
• selective reverse mutation
• regulation
Para. 3
• carrier / vector
• therapeutic gene
• target cell
• genetically altered
• evolve a way of：develop a way of 具备…途径
• encapsulate：把…密封于… ；压缩
• capability
• manipulate: to use or control sth. with skill
Para. 4
• unload into: release into
• generation
• restore to
• e.g.
治疗性基因生成新一代功能性蛋白质使靶细胞
恢复到正常状态。
Para. 6
• retroviruses:逆转录酶病毒
• double-stranded:双链
• integrated:整合
• host cell
Para. 8
single-stranded DNA viruses:
单链DNA病毒
chromosome 19:
19号染色体
The 24 human chromosome
territories during prometaphase
in fibroblast cells.
Para. 9
• herpes simplex virus type 1: I型单纯疱疹
• cold sores 感冒疮; 唇疱疹
Cold sores are small, painful, fluid-filled blisters or
sores that appear on the lips, mouth, or nose that
are caused by a herpes simplex virus infection.
The sores can be painful and usually last a few days.
Unlike most viral infections, the cold sore virus is not
completely eliminated by the body defenses. For this
reason, cold sores often recur.
Para. 10
• virus-mediated
• gene-delivery
• non-viral options ( for )
non-viral approach
Para. 11
• artificial lipid sphere: 人工脂质球
• an aqueous core: 水质核
• liposome: 脂质体
A liposome is a tiny bubble (vesicle), made out of the
same material as a cell membrane. Liposomes can be
filled with drugs, and used to deliver drugs for cancer
and other diseases.
Para. 12
• chemically:以化学方法
• bind/bound ( to ): link / linked to
• cell receptors: …受体
• therapeutic DNA constructs: …结构
• engulfed by: 被细胞膜吞噬
Para. 13
• autonomously alongside:
• mutation
• substantial amount of: considerable amount of
• construction and autonomy: 结构和自主性
• genetic code
• anticipate: expect
• potential method: promising method
具有应用前景的方法
Para. 14
• for sale: 销售
• clinical trial
• suffer a major setback: 受到重创
• multiple organ failures
• triggered by: caused by
• adenovirus carrier: 腺病毒载体
• OTCD
Ornithine transcarboxylase deficiency (OTCD), the
most common of the urea cycle disorders, is a rare
metabolic disorder, occurring in one out of every 80,000
births. OTCD is a genetic disorder resulting in a mutated
and ineffective form of the enzyme ornithine
transcarboxylase.
Para. 15
• major blow: 重大打击
• place a halt on: stop
• retroviral vector:逆转录酶病毒载体
• leukemia-like condition: 疑似白血病的病症
• X-SCID:
针对由染色体X基因传导的重症联合免疫缺陷
bubble baby syndrome
• Bubble baby syndrome, known as X-linked severe
combined immunodeficiency (X-SCID) is caused by
a genetic condition that affects the immune system.
Babies born with X-SCID need to be shielded from all
infections at birth and have to be kept in a sterile
environment, 'a bubble', or they can die in their first
year from infections such as pneumonia or chicken pox.
Gene therapy for X-SCID has been used to treat
children who were unable to find a suitable bone
marrow donor. It has been extremely successful in
restoring the children's immune function enabling
them to live fuller and healthier lives. Unfortunately,
as with all medicines, there can be side effects. One of
the first children in Britain to receive gene therapy for
'bubble baby syndrome' has developed leukaemia as a
result of his treatment.
Para. 16
• BRMAC: 生物反应调节剂咨询委员会
• proceed with
• appropriate safeguards: proper protection
Para. 17
• short-lived / long-lived: for short / long period
• integrate into
• rounds of the therapy:多轮的治疗
Para. 19
Viruses, while the carrier of choice in most gene therapy
studies, …
尽管病毒是多数基因疗法研究的首选载体
gene control and targeting issues
基因调控和靶向问题
Para. 20
the best candidates for:
由单个基因异常所导致的疾病最适合采用基因治疗
variations in genes 基因变异
Para. 21
• coated in: embedded in 包埋于
• polyethylene glycol ( PEG ):聚乙二醇
• potential: n.
• Parkinson’ s disease
• blood-brain barrier
The blood-brain barrier (BBB) is a metabolic or
cellular structure in the central nervous system (CNS)
that restricts the passage of various chemical substances
and microscopic objects (e.g. bacteria) between the
bloodstream and the neural tissue itself, while still
allowing the passage of substances essential to metabolic
function (e.g. oxygen).
Para. 22
• RNA interference ( RNAi ) : 干扰核糖核酸
近年来的研究表明,一些小的双链RNA可以高效、特异的
阻断体内特定基因表达，促使mRNA降解，诱使细胞表现
出特定基因缺失的表型，称为RNA干扰（RNA
interference，RNAi，也译作RNA干预或者干涉）。它也
是体内抵御外在感染的一种重要保护机制。
• gene silencing: 基因封阻，基因沉默
研究结果发现有大量的转基因植株不能正常表达，通常
这并不是由于转基因的缺失或突变引起的，而是基因失
活的结果.这种失活的现象称为基因沉默。
• siRNA（small interfering RNAs）:短小干扰核糖核酸,
一种短片断双链RNA分子，能够以同源互补序列的
mRNA 为靶目标降解特定的mRNA，这个过程就是
RNA干扰途径（RNA interference pathway）。
• degrade RNA of a particular sequence:
降解核糖核酸的特殊序列
• messenger RNA: 信使核糖核酸
• Huntington’s disease
Huntington's disease, also called Huntington's chorea,
chorea major, or HD, is a genetic neurological disorder
characterized after onset by uncoordinated, jerky body
movements and a decline in some mental abilities. These
characteristics vary per individual, physical ones less so,
but the differing decline in mental abilities can lead to a
number of potential behavioral problems. The disorder
itself isn't fatal, but as symptoms progress,
complications reducing life expectancy increase.
• Research of HD has increased greatly in the last few
decades, but its exact mechanism is unknown, so
symptoms are managed individually. Globally, up to 7
people in 100,000 have the disorder, although there are
localized regions with a higher incidence. Onset of
physical symptoms occurs gradually and can begin at
any age, although it is statistically most common in a
person's mid-forties (with a 30 year spread). If onset is
before age twenty, the condition is classified as juvenile
HD.
• The disorder is named after George Huntington, an
American physician who published a remarkably
accurate description in 1872. In 1983 a marker for the
altered DNA causing the disease was found, followed a
decade later by discovery of a single, causal, gene. As it
is caused by a single gene, an accurate genetic test for
HD was developed; this was one of the first inherited
genetic disorders for which such a test was possible.
Due to the availability of this test, and similar
characteristics with other neurological disorders, the
amount of HD research has increased greatly in recent
years.
• George Huntington
(April 9, 1850 – March 3, 1916)
was an American physician.
Para. 23
• thalassemia 地中海贫血
Thalassemia, also known as Mediterranean Anemia,
Cooley's Anemia or Homozygous Beta Thalassemia,
is a group of inherited disorders in which there is a
fault in the production of hemoglobin (oxygen-carrying
pigment found in red blood cells).
• Causes and Risk Factors of Thalassemia
Thalassemia is a genetically determined disease. It
tends to be found in individuals whose families come
from the Mediterranean region, Africa, and
sometimes Asia.
• Symptoms of Thalassemia in severe condition:
 Paleness
 Headaches
 Fatigue
 Shortness of breath
 Jaundice
 Spleen enlargement
Cystic fibrosis 囊性纤维化
• Cystic fibrosis (CF) is an inherited disease of your
mucus and sweat glands. It affects mostly your lungs,
pancreas, liver, intestines, sinuses, and sex organs.
• Normally, mucus is watery. It keeps the linings of certain
organs moist and prevents them from drying out or
getting infected. But in CF, an abnormal gene causes
mucus to become thick and sticky.
• The mucus builds up in your lungs and blocks the
airways. This makes it easy for bacteria to grow and
leads to repeated serious lung infections. Over time,
these infections can cause serious damage to your lungs.
• The thick, sticky mucus can also block tubes, or ducts,
in your pancreas. As a result, digestive enzymes that
are produced by your pancreas cannot reach your
small intestine. These enzymes help break down the
food that you eat. Without them, your intestines cannot
absorb fats and proteins fully.
•
•
•
•
As a result:
Nutrients leave your body unused, and you can become
malnourished.
Your stools become bulky.
You may not get enough vitamins A, D, E, and K.
You may have intestinal gas, a swollen belly, and pain
or discomfort.
• The abnormal gene also causes your sweat to become
extremely salty. As a result, when you perspire, your
body loses large amounts of salt. This can upset the
balance of minerals in your blood. The imbalance may
cause you to have a heat emergency.
• CF can also cause infertility (mostly in men).
• The symptoms and severity of CF vary from person to
person. Some people with CF have serious lung and
digestive problems. Other people have more mild
disease that doesn't show up until they are adolescents
or young adults.
• Respiratory failure is the most common cause of death
in people with CF.
• Until the 1980s, most deaths from CF occurred in
children and teenagers. Today, with improved
treatments, people with CF live, on average, to be
more than 35 years old. Research continues to look for:
 Better treatments
 A cure
Other Names for Cystic Fibrosis
• CF
• Cystic fibrosis of the pancreas
• Fibrocystic disease of the pancreas
• Mucoviscidosis
• Mucoviscidosis of the pancreas
• Pancreas fibrocystic disease
• Pancreatic cystic fibrosis
Para. 25
• 25 nanometers across
• pores in the nuclear membrane: 核膜孔隙
pore---- A minute opening in tissue, as in the skin of
an animal, serving as an outlet for perspiration, or in
a plant leaf or stem, serving as a means of absorption
and transpiration.
Para. 26
sickle cell: 镰状细胞贫血
• Sickle-cell disease or sickle-cell anaemia (or anemia) is
a blood disorder characterized by red blood cells that
assume an abnormal, rigid, sickle shape. Sickling
decreases the cells' flexibility and results in a risk of
various other complications. Life expectancy is
shortened, with studies reporting an average life
expectancy of 42 and 48 years for males and females,
respectively.
• When sickle-shaped cells block small blood vessels, less
blood can reach that part of the body. Tissue that does
not receive a normal blood flow eventually becomes
damaged. This is what causes the complications of
sickle cell disease. There is currently no universal cure
for sickle cell disease.
• Sickle-cell disease occurs more commonly in people
(or their descendants) from parts of tropical and subtropical regions where malaria is or was common.
Sickle-shaped
red blood cells
Para. 27
demean: to deprive of esteem, self-worth, or effectiveness；
to lower in character or quality 贬损
somatic gene therapy: 体细胞基因治疗
germline gene therapy: 生殖细胞基因治疗
preliminary: preparatory 预备的; 初步的
have access to ( therapies )
access (to sth.)---the chance or right to use or have sth.
e.g. Do you have access to a personal computer ?
Phrases in the text
1.
2.
3.
4.
5.
6.
7.
8.
9.
Sequences of bases
Genetic disorders
Defective genes
Homologous recombination
Selective reverse mutation
Target cells
Human immunodeficiency virus
Herpes simplex viruses
Cold sores
10. Therapeutic DNA
11. Genetic code
12. Clinical trials
13. Multiple organ failures
14. A permanent cure
15. Viral vector
16. Multigene disorders
17. RNA interference
18. Gene silencing
19.
20.
21.
22.
23.
24.
25.
blood-brain barrier
Cystic fibrosis
Pores in nuclear membrane
Sickle cell
Somatic / germline gene therapy
Huntington’s disease
Bubble baby syndrome