Topic tiếng anh chuyên ngành sinh học

Class: L01. Bio – English
Teacher: Lê Thọ Sơn
Group 4
Member of group 4:
Nguyễn Thị Hồng Lý - 1353071260
Nguyễn Thị Phương Lan - 1353071273
Nguyễn Thị Hiền - 1353071264
Vương Thị Oanh - 1353070101
Nguyễn Thị Nhung - 1353071228
Đặng Phan Hiền - 1353010534
Nguyễn Thanh Tuấn - 1353070064
Nguyễn Anh Dũng - 1353071266
Phạm Như Quỳnh - 1353071294


Welcome to our topic:

Embryonic Stem cells
Text : Embryonic stem cells
Terminology/glossary
Bio - grammar
I
II
III
Contents

I. Text
Embryonic Stem cells

Embryonic stem cells have huge potential in the field of tissue engineering and regenerative medicine as they hold the capacity to produce every type of cell and tissue in the body. In theory, the treatment of human disease could be revolutionized by the ability to generate any cell, tissue, or even organ, `on demand` in the laboratory.

This work reviews the history of murine and human ES cell lines, including practical and ethical aspects of ES cell isolation from pre-implantation embryos, maintenance of undifferentiated ES cell lines in the cell culture environment, and differentiation of ES cells in vitro and in vivo into mature somatic cell types. Finally, we discuss advances towards the clinical application of ES cell technology, and some of the obstacles which must be overcome before large scale clinical trials can be considered.




INTRODUCTION
WHAT IS A STEM CELL?

Two properties are generally considered to define a stem cell, the capacity for long-term self- renewal without senescence, the ability to differentiate into one or more specialized cell types. These cells could therefore provide a theoretically inexhaustible supply of cells for transplantation. Totipotent stem cells, which have an ability to generate all tissue types, play a critical role in human development, providing the raw material for the development of all tissues and organs in the embryo and all the extra-embryonic tissues.
However, tissue-specific stem cells are also deposited in various niches throughout the body, such as bone marrow, brain, liver and skin, as a mechanism for tissue maintenance, growth and repair in later life. These `adult` stem cells were originally thought to be committed to regenerating only a very restricted set of cell lineages. However, it is becoming increasingly evident that they can show considerably more plasticity.

In theory, these cells could be harvested from a patient, differentiated in the laboratory and transplanted back into the same individual for tissue repair, thus bypassing the need for immune suppression. However, for some stem cell types, low frequency, difficulties in accessing the niche and isolating the cells, restricted lineage potential and poor growth in cell culture may render their use impractical for tissue engineering purposes. In these cases, ES cells are likely to provide a more appropriate cell source.





The first pluripotent cell lines to be established were embryonic carcinoma (EC) cell lines, derived from the undifferentiated compartment of murine and human germ cell tumours. These cells could be expanded continuously in culture and could also be induced to differentiate into derivatives of all three embryonic germ layers; endoderm, ectoderm and mesoderm. Murine EC cells can also contribute extensively to all the normal tissues of chimaeric mice generated by the injection of EC cells into mouse blastocysts. However, being cancer-derived and usually aneuploid, EC cells are not suitable for clinical application, although they have proven to be a very useful model system in the laboratory.
Murine ES cells were first isolated in 1981, using culture techniques based on experience with the culture of EC cells. ES cells are derived from the pre-implantation blastocyst, a hollow sphere of cells containing an outer layer of trophoblast cells which give rise to the placenta and the inner cell mass (ICM), from which ES cells are derived. Cells of the ICM ultimately go on to form the embryo proper and therefore have the capacity to form all the tissues in the body. Although these truly pluripotent cells are relatively short-lived in the embryo in vivo, they can be propagated indefinitely in culture in an undifferentiated state, by growth in the presence of leukaemia inhibitory factor (LIF) and/or on a feeder layer of murine embryonic fibroblasts (MEF).
Murine ES cells have had an enormous impact on many fields of research over the last 20 years. In particular, ES cells can be used to reconstitute early mouse embryos, and this has formed the basis of genome manipulation technology that has produced hundreds of `knock out` and `knock in` transgenic animals for the investigation of gene expression and regulation in vivo.


ES cells also allow studies of the initial stages of mammalian development in vitro, without the need to harvest peri-implantation embryos, and continue to be used to dissect the basic mechanisms underlying pluripotency and cell lineage specification. Not surprisingly, significant efforts have been made to isolate ES cells from other species and, to date, ES cell lines are available from rodents, rabbits, pigs, primates and significantly, an ever-increasing number from humans.
The generation of human ES cell lines has sparked a great deal of controversy in the media, with particularly strong objections being raised to the use of human embryos in scientific research by certain religious communities. Legislation governing the use of human embryos to produce ES cell lines varies between countries and, at the time of writing, is still under debate in many cases.
The initial human ES cell lines were derived from `spare` embryos produced by in vitro fertilization and donated with the informed consent of the parents. This source is widely held to be the most acceptable source of embryos for research, the embryos being originally created for reproductive, not scientific, purposes. Many people consider it to be ethically superior to use these embryos for medical research from which the human population as a whole is likely to benefit, than to simply destroy them or store them indefinitely.
An alternative method of deriving human ES cells is somatic nuclear transfer, or cloning, which bypasses the need to destroy an embryo produced `naturally` by the fusion of sperm and egg, which could otherwise develop to term if implanted. This procedure was first described in sheep, where a somatic cell nucleus was transferred into an enucleated oocyte leading to apparently normal embryonic development in a proportion of cases.
Cloned embryos have since been generated in a number of species, using a variety of somatic cell types. The clinical development of regenerative medicine could be markedly expedited by the use of autologous cloned human embryos as it would circumvent any potential problems with the rejection of foreign cells, which remains the bane of transplantation medicine.
However, the creation of a cloned human embryo specifically for the purposes of research is even more ethically loaded than the use of `spare` embryos from IVF treatment. In all cases where animal embryos have been successfully cloned using this technique, a small proportion of embryos have survived and developed to become live young after implantation. The even remote possibility of generating a live human clone has been sufficient to ban the technique of somatic nuclear transfer from being applied to human cells in most western countries. Although there has been a single scientific report of the cloning of a human embryo, these results have met widespread scepticism as the embryos were only allowed to develop to the 6-cell stage, before nuclear DNA begins to regulate embryonic development.
However, a report of the cloning of non-human primate embryos suggests that cloning by nuclear transfer is technically possible in humans, and ES cells have been recently developed by somatic nuclear transfer of human nuclei into rabbit oocytes. Although this latter work was carried out to avoid the use of human oocytes, which are in short supply for clinical use and difficult to obtain for scientific research, the creation of a `human-rabbit hybrid` added fuel to the fire of an already acrimonious debate. Nevertheless, the universally extreme inefficiency of somatic nuclear transfer in generating viable embryos (less than 1% development to blastocysts of cloned rhesus money embryos) is likely to render it impractical for human use, even if the cloning of human embryos were to become less morally dubious.
II. Terminology/ glossary
Alternative method /ɔːlˈtɜːnətɪv/ /ˈmeθəd/ phương pháp thay thế
Aneuploid / ˈanyoˌploid/ : thể lệch bội
Blastocysts : phôi nang
Cell lineage(danh từ) : dòng tế bào.
Chimaeric mice: chuột khảm
Clinical / `klinikəl/ lâm sàng
Cloned /kloʊn/ nhân bản vô tính
Controversy (n) /ˈkɒntrəvɜːsi/: cuộc tranh luận
Ectoderm / ˈektəˌdərm/ : ngoại bì
Embryonic carcinoma / embri`ɔnik kɑ:si`noumə/ : phôi ung thư biểu mô
Endoderm /ˈendəˌdərm/ : nôi bì
Established /is`tæbli∫/ : thành lập, tìm thấy
Ethically superior /suːˈpɪəriər/ đạo đức cao
Expanded / ikˈspandid / : nhân lên
Fertilization (n) /ˌfɜːtɪlaɪˈzeɪʃən/ thụ tinh
Gene expression /ikˈspresʃən / : biểu hiện gen
Generation /ˌdʒenəˈreɪʃən/ : thế hệ
Implantation (n) /implɑ:n`teiʃn/ sự đóng sâu vào
In definitely (v) /ɪnˈdefɪnətli/ vô thời hạn
Inner cell mass/ ˈinər sel mæs/ : khối tế bào trong
Laboratory (n) /ləˈbɒrətəri/ phòng thí nghiệm
Leukamia inhibitory /luːˈkiː.mi.ə// in`hibitəri/ để ngăn chặn, để hạn chế, để kiềm chế bệnh bạch cầu
Manipulation/mə,nipju`leiʃn/ :thao tác
Mesoderm / ˈmezəˌdərm/ : trung bì
Niches /nitʃ/ : ổ ( trong cơ thể tế bào gốc được cất giữ tại những vị trí đặc biệt gọi là “ổ” tế bào gốc).
Oocytes / `ouəsait/ tế bào trứng
Plasticity: /plæsˈtɪs.ə.ti/ tính linh hoạt.
Pluripotent /plooriˈpotnt/: đa năng
Primates/prai`meiti:z/ :(động vật học) bộ động vật có tay, bộ động vật linh trưởng
Regenerating (v) /rɪˈdʒen.ə.reɪt/ tái sinh


Religious communities (n) /rɪˈlɪdʒəs/ /kəˈmjuːnəti/ :cộng đồng tôn giáo
Rodent /`roudənt/ :(thuộc) bộ gặm nhấm
Scientific (adj) /ˌsaɪənˈtɪfɪk/ khoa học
Self- renewal: /self/ /rəˈnjuː/ tính chất tự làm mới.
Somatic nuclear transfer(n) chuyển nhân tế bào soma
Specialized: /ˈspeʃəl/ chuyên biệt.
Totipotent stem cells: tế bào gốc tổng năng
Transgenic :chuyển gen
Transplanted (n) /trænˈsplɑːnt/ cơ quan được cấy ghép
Undifferentiated compartment /,ʌndifə`ren∫ieitid kəm`pɑ:tmənt/ : khoang không biệt hóa
III. Bio - grammar
Grammar 1: maintenance of (duy trì sth)
This work reviews the history of murine and human ES cell lines, including practical and ethical aspects of ES cell isolation from pre-implantation embryos, maintenance of undifferentiated ES cell lines in the cell culture environment, and differentiation of ES cells in vitro and in vivo into mature somatic cell types.
Xem xét lại lịch sử của các dòng tế bào phôi gốc ở người và chuột, bao gồm các lợi ích và khía cạnh đạo đức của việc phân lập tế bào phôi gốc từ phôi nuôi cấy ban đầu, duy trì các dòng tế bào phôi gốc không phân hóa trong môi trường nuôi cấy, và sự phân biệt của các tế bào phôi gốc trong ống nghiệm và trong các dòng tế bào soma trưởng thành.

Grammar 2 : the ability to (có khả năng…)
Two properties are generally considered to define a stem cell, the capacity for long-term self- renewal without senescence and pluripotency, the ability to differentiate into one or more specialized cell types.
Có hai tính chất được coi là để xác định một tế bào gốc, có sự đổi mới liên tục mà không có sự lão hóa, khả năng phân hóa thành một hoặc nhiều dòng tế bào chuyên biệt.
Grammar 3 : supply of (cung cấp cái gì đó)
These cells could therefore provide a theoretically inexhaustible supply of cells for transplantation.
Các tế bào này có thể cung cấp một nguồn tế bào vô hạn cho sự thay thế bộ phận cơ thể
 
Grammar 4: harvested from ( thu hoạch từ/ lấy từ sb)
In theory, these cells could be harvested from a patient, differentiated in the laboratory and transplanted back into the same individual for tissue repair, thus bypassing the need for immunosuppression
Theo lý thuyết, các tế bào có thể được lấy từ một bệnh nhân, phân hóa trong phòng thí nghiệm và ghép trở lại trong cơ thể bệnh nhân để thay thế các mô bệnh, từ đó bỏ qua sự suy giảm miễn dịch.
Grammar 5: derived from (có nguồn gốc từ…)
The first pluripotent cell lines to be established were embryonic carcinoma (EC) cell lines, derived from the undifferentiated compartment of murine and human germ cell tumours.
Dòng tế bào tủy đầu tiên được tạo từ dòng tế bào phôi ung thư, có nguồn gốc từ ngăn sự không biệt hóa khối u tế bào mầm ở người và chuột.
Grammar 7: give rise to (làm phát sinh…)
ES cells are derived from the pre-implantation blastocyst, a hollow sphere of cells containing an outer layer of trophoblast cells which give rise to the placenta and the inner cell mass (ICM), from which ES cells are derived.
Các tế bào phôi gốc có nguồn gốc từ sự nuôi cấy phôi nang ban đầu, một tế bào cầu rỗng chứa lớp ngoài của tế bào lá nuôi phôi làm phát sinh ra nhau thai và khối bên trong có nguồn gốc từ tế bào phôi gốc.
Grammar 8 : The generation of ( các thế hệ của…)
The generation of human ES cell lines has sparked a great deal of controversy in the media, with particularly strong objections being raised to the use of human embryos in scientific research by certain religious communities.
Các thế hệ của dòng tế bào ES con người đã gây ra rất nhiều tranh cãi trong các phương tiện truyền thông, với sự phản đối mạnh mẽ đặc biệt được nâng lên việc sử dụng phôi thai người trong nghiên cứu khoa học của các cộng đồng tôn giáo nào đó.
Grammar 9: The creation of (việc tạo ra ………)
However, the creation of a cloned human embryo specifically for the purposes of research is even more ethically loaded than the use of `spare` embryos from IVF treatment.
Tuy nhiên, việc tạo ra một phôi người nhân bản đặc biệt cho mục đích nghiên cứu thậm chí còn hơn đạo đức nạp hơn việc sử dụng phôi `phụ tùng` từ điều trị IVF.


TIME TO SAY GOOD BYE!