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'''Identify a recent research article (using the pubmed tags to cite) on iPS cells and summarise in a few paragraphs the main findings of the paper.'''
'''Identify a recent research article (using the pubmed tags to cite) on iPS cells and summarise in a few paragraphs the main findings of the paper.'''


A recent research article on iPS cells is one entitled ''iPS cells reprogrammed from human mesenchymal-like stem/progenitor cells of dental tissue origin'' from Columbia University, New York, in 2010.<ref><pubmed>19795982</pubmed></ref>
A recent research article on induced pluripotent stem (iPS) cells is one entitled ''iPS cells reprogrammed from human mesenchymal-like stem/progenitor cells of dental tissue origin'' from Columbia University, New York, in 2010.<ref><pubmed>19795982</pubmed></ref> The article acknowledged the usefulness of iPS cells in medical treatments and therapies but noted that human sources of precursor cells to be induced are limited to only a few types, notably dermal fibroblasts on which the original studies were carried out. The paper investigated a new source of human iPS cells - cells derived from dental tissue.
 
Such dental tissue is readily available through the deciduous teeth lost in childhood and the third molars which are commonly removed in adulthood. Using ectomesenchyme derived cells from such dental tissue, they were able to induce pluripotency in the cells using either the four factors Lin28/Nanog/Oct4/Sox2 or c-Myc/Klf4/Oct4/Sox2. The iPS cells that were produced exhibited a morphology indistinguishable from human embryonic stem cells, and the paper concluded that dental tissue serves as an excellent alternative resource for generating iPS cells.


==References==
==References==


<references/>
<references/>

Revision as of 13:38, 17 October 2012

Lab Attendance

Lab 1 -- Z3373894 11:49, 25 July 2012 (EST)

Lab 2 -- Z3373894 10:37, 1 August 2012 (EST)

Lab 3 -- Z3373894 10:06, 8 August 2012 (EST)

Lab 4 -- Z3373894 10:23, 15 August 2012 (EST)

Lab 5 -- Z3373894 10:05, 22 August 2012 (EST)

Lab 6 -- Z3373894 10:02, 29 August 2012 (EST)

Lab 7 -- Z3373894 10:14, 12 September 2012 (EST)

Lab 8 -- Attended lab but forgot to sign attendance. Sorry!

Lab 9 -- Z3373894 10:02, 26 September 2012 (EST)

Lab 10 -- Z3373894 10:06, 3 October 2012 (EST)

Lab 11 -- Z3373894 10:04, 10 October 2012 (EST)

Lab 12 -- Z3373894 10:08, 17 October 2012 (EST)


Lab 1 Assessment

1. Identify the origin of In Vitro Fertilization and the 2010 nobel prize winner associated with this technique and add a correctly formatted link to the Nobel page.

In vitro fertilisation (IVF) has its origins in the 1970s, specifically 1978 when the first successful birth of an IVF baby occurred. This birth was the result of the work of physiologist Robert G. Edwards, who developed the technique and subsequently won the Nobel Prize in Physiology or Medicine 2010 for his work. The procedure involves removing a healthy ovum from the mother and fertilising it outside of the female's body, where the term in vitro, which is Latin for "in glass" comes from. Today, this term is used to describe any procedure that takes place outside of the body, in opposition to an in vivo procedure which takes place inside the body. The zygote is then implanted back into the woman's uterus where it can develop normally.[1]


2. Identify and add a PubMed reference link to a recent paper on fertilisation and describe its key findings (1-2 paragraphs).

A recent paper published on the topic of fertilisation includes a paper from researchers at the University of Pisa in Italy entitled DHEA supplementation improves follicular microenviroment in poor responder patients.[2] This study looked at a group of 24 women aged between 31 and 42 diagnosed with poor ovarian response (POR) in which fewer follicles properly develop. These women were randomly split into two groups; one of which received no special treatment prior to IVF, while the other group received dehydroepiandrosterone (DHEA) supplementation, which was hypothesised to increase the quality of the oocytes and therefore increase the chance of a successful pregnancy.

The results showed that the group of women that received DHEA supplementation prior to IVF had lower levels of HIF1 in their follicular fluid; a substance produced by the body in response to low oxygen levels. This suggests that DHEA increases the supply of oxygen to the developing follicle and thus increases its quality, as it had been previously shown that oxygen plays a very important role in follicle development. Although the study demonstrated with statistical significance that supplementation with DHEA led to higher levels of HIF1, it could not be shown that supplementation led to better IVF outcomes, however this was attributed to the small sample size. The study concluded that DHEA supplementation is a viable option to increasing follicle development in women with POR as it is relatively cheap, easily administered and has minimal side effects.


Lab 2 Assessment

File:Macaque Oocyte.jpg
A recently fertilised macaque oocyte.[3]

1. Upload an image from a journal source relating to fertilization or the first 2 weeks of development as demonstrated in the practical class. Including in the image “Summary” window: An image name as a section heading, Any further description of what the image shows, A subsection labeled “Reference” and under this the original image source, appropriate reference and all copyright information and finally a template indicating that this is a student image. ----

Note - This image was originally uploaded as part of an undergraduate science student project and may contain inaccuracies in either description or acknowledgements. Students have been advised in writing concerning the reuse of content and may accidentally have misunderstood the original terms of use. If image reuse on this non-commercial educational site infringes your existing copyright, please contact the site editor for immediate removal.

The image to the left is from a journal article that investigated both in vivo and in vitro fertilisation in the macaque monkey. It shows a macaque oocyte containing both the maternal and paternal pronuclei. The link to this article can be found both below in 'references' and also in the description of the image.


2. Identify a protein associated with the implantation process, including a brief description of the protein's role.

A protein associated with the implantation process is the glycoprotein fibronectin. It is involved in cell adhesion, growth, migration and differentiation; making it important in many bodily processes including wound healing and embryo implantation. In implantation, it guides cell attachment and migration, and the absence of fibronectin leads to defects in mesodermal, neural tube and vascular development; causing early embryo death.[4]








Lab 3 Assessment

1. Identify the difference between "gestational age" and "post-fertilisation age" and explain why clinically "gestational age" is used in describing human development.

Gestational age is the time that has elapsed since the pregnant woman's last menstrual period began, measured in weeks. Post-fertilisation age is the time that has elapsed since the oocyte was fertilised by the sperm, also measured in weeks. Fertilisation reliably occurs 2 weeks after the last menstrual period, so gestational age is roughly 2 weeks greater than the post-fertilisation age. Gestational age is used clinically to describe human development as it is often difficult to identify the precise timing of fertilisation, thus the time since the last menstrual period (gestational age) is more convenient. Using gestational age, a pregnancy can be identified as premature or postmature. This identification has implications for a successful birth, as premature babies have a greater risk of complications and death.[5]


2. Identify using histological descriptions at least 3 different types of tissues formed from somites.

Three different types of tissues formed from somites include the dermis (from dermatomes), skeletal muscle (from myotomes) and bone (from sclerotomes). Histologically, the dermis is an area of connective tissue under the outer, keratinised epidermis, that contains blood vessels and nerve endings. Skeletal muscle is muscle that appears striated and is under voluntary control by the nervous system. Bone is a specialised form of connective tissue that is organised into compact and spongy forms. The compact components provide rigidity while spongy bone works to distribute loads across the bone.[6]


Lab 4 Assessment

1. Identify the 2 invasive prenatal diagnostic techniques related to the placenta and 2 abnormalities that can be identified with these techniques.

An invasive prenatal diagnostic technique related to the placenta is an amniocentesis. This involves inserting a needle through the mother's abdomen and collecting a sample of the amniotic fluid, which contains cells shed by the fetus. Through analysis, this technique can identify chromosomal disorders such as Down syndrome as well as open neural tube defects such as spina bifida.[7]

Another invasive prenatal diagnostic technique is chorionic villus sampling (CVS). This involves inserting a catheter through the cervix and removing a small sample of placental tissue, which has the same genetic material as the fetus. This can then be tested for chromosomal abnormalities like Down syndrome, however cannot detect neural tube defects such as spina bifida, which an amniocentesis can detect.[8]


2. Identify a paper that uses cord stem cells therapeutically and write a brief (2-3 paragraph) description of the paper's findings.

A paper that uses umbilical cord stem cells therapeutically is one from a group of researchers at Seoul National University in South Korea entitled Comparison of Mesenchymal Stem Cells Derived from Fat, Bone Marrow, Wharton's Jelly, and Umbilical Cord Blood for Treating Spinal Cord Injuries in Dogs.[9] They induced spinal cord injuries in dogs through the use of balloon catheter compression and then applied stem cells from a variety of sources to the site of injury and compared the recovery that was achieved between the different groups.

It was found that all stem cell treatments produced significant improvements in locomotion at 8 weeks after implantation, and that this was accompanied by increased numbers of neurons and neurofilament-positive fibers at the lesion site. However it was also found that even though the umbilical cord stem cells produced no greater improvement in locomotion than the other stem cells, the umbilical cord stem cells produced more nerve regeneration and anti-inflammation activity.

Lab 5 Assessment

Completing the in class Quiz!


Lab 6 Assessment

To Be added.


Lab 7 Assessment

1. (a) Provide a one sentence definition of a muscle satellite cell (b) In one paragraph, briefly discuss two examples of when satellite cells are activated ?

A muscle satellite cell is a mononuclear progenitor cell containing very little cytoplasm found between muscle fibres.

Two examples of when satellite cells are activated occur during normal muscle growth and when the muscle is damaged. In both cases, under mechanical strain the satellite cells are activated and either form new muscle fibres or fuse to existing muscle fibres to make them larger.[10]


Lab 8 Assessment

Individual assessment this week relates to your group project.

1. Each student should now look at each of the other Group projects in the class.

2. Next prepare a critical assessment (should include both positive and negative issues) of each project using the project assessment criteria.

3. This assessment should be pasted without signature on the top of the specific project's discussion page (minimum length 3-5 paragraphs/project).

4. This critical assessment should also be pasted on your own student page. Each student should therefore have 5 separate reports pasted on their own page for this assessment item. Length, quality and accuracy of your reports will be part of the overall mark for this assessment (there will be a greater loading on this than simple question assessments).


Somatosensory

The introduction provides a good overview however using the wiki in-text citation system will make it neater.

The history section has made a good start but this can be elaborated on further. Once again, referencing can be improved here.

The central somatosensory section has been well researched and the referencing is good. It would be preferable to label figures as "figure 1" etc as this makes it easy to refer to. The drawing is good and has a good explanation however the "student template" should be added.

The touch/pain/hot and cold/pressure sections have a lot of information on their function but not so much information relating to embryological development. Some sections are well referenced, other bits are referenced without the wiki format, and other sections aren't really referenced at all. This can be improved. Adding pictures to these sections to illustrate points will also be helpful.

The current research section, although small, is very good, well referenced, good inclusion of the figure however this could be given a name such as "figure 2". Adding more current research with variation in the topics covered will make this section even more interesting.

The glossary and external links are good - keep adding to these throughout the project.



Taste

The introduction is good, explaining the function and mechanisms behind.

The taste map text and picture are useful however lack referencing information.

The cortical areas section is very interesting and well referenced.

The table timeline is a very good way to summarise the development of taste. It is succinct and well referenced, even though one paper was referred to for most of the information.

The history table is similarly good, very succinct and straightforward, however lacks some references, and the references that were included could be improved by using the wiki referencing system.

The structure and function section is useful but doesn't add much to the text in terms of embryological development. Also make sure the images are properly referenced with the "student template" included.

The abnormalities section is very good and well researched, although maybe try and avoid referring to the articles that have been researched in the text and rather just refer to them using the wiki referencing system. The images are good as well but don't forget the "student template" here also.

The current research section is interesting and well researched, the use of succinct subheadings to summarise the paper's findings was good.

The useful links and image sections need to be added to, and the glossary section can be improved by putting the key terms in bold, but that is otherwise good.



Olfaction

The introduction provides a good overview to the topic and the associated images have all the appropriate referencing information.

The history section is interesting and well researched with good use of subheadings.

The timeline of development is very useful and informative however is quite text-heavy, some diagrams may be able to help here.

The anatomy and normal function sections don't add very much to the page, especially in terms of embryological development. Adding more to these sections may help.

The abnormalities section is good, with a lot of information on Kallmann's syndrome, however other abnormalities (if there are any?) could be included to expand this section.

The current research section contains a lot of information in a small amount of space. It is quite jargon-heavy although this might not be able to be avoided. The subheadings are good as they act to split this section into discrete units.

The glossary and external links are very good, and the references are extensive which is good.



Abnormal Vision

The introduction was okay, however avoid referring to the rest of the page within the introduction - it should stand on its own.

Normal eye development is very succinct, however maybe consider adding an image here to aid with your explanation.

The abnormal section is very good and well researched. The images included are good, however as with the introduction, avoid using language such as "in the section below, we have focused on..."

The ocular manifestations section is very good but just needs to be organised better, the headings are somewhat confusing. Good use of images, timeline, and subheadings for different genes. The management section is also very interesting and can be elaborated on.

The glossary is good but the formatting can be improved - perhaps putting the key terms in bold or at least making all the terms italic rather than half and half.

The reference list is extensive which is good, but don't forget to add to the external links section.



Hearing

The introductory image at the top of the page is very good but the "can you hear me' bit was overkill for me - maybe consider revising that. Also the small spelling mistake at the start of the introduction (should be senses not sense) is quite off-putting and should be fixed. Otherwise a good introduction.

The history timeline is very good and serves as another good introduction to the topic. Some external links are missing here though.

For development there is a lot of information in the outer ear section but not much in the middle and inner sections - it looks imbalanced and may be improved by adding to the other sections or perhaps splitting up the sections differently. Other than this the development section is very good with a lot of well researched information. The images are also good but don't forget to add the "student template". The inclusion of the summary box is a very good idea and is a good feature of the page.

The abnormal section is also very good and well researched. The subheadings are used effectively and the tables are a good addition. Adding images in the tables as well as the text will help to break up the text and promote interest.

The technology sections are an interesting addition however could be improved by referencing using the wiki system rather than standard in-text citations.

A good start has been made in the current research section however if possible add more current topics of research.

The glossary is very good and the references are extensive however don't forget to add to the external links.


Lab 9 Assessment

1. Identify and write a brief description of the findings of a recent research paper on development of one of the endocrine organs covered in today's practical.

A recent research paper on the development of the pancreas is one from 2000 (getting a bit old now, I suppose) entitled Regulation of pancreas development by hedgehog signaling.[11] In this paper, the researchers investigated the effect that the factors Sonic hedgehog, Indian hedgehog and Patched 1 have on development of the pancreas by observing the effect that mutations leading to the absence of these factors have on the organism. They found that Sonic hedgehog represses the growth of the pancreas and is important in limiting its size. For example, if the tissues surrounding the pancreas are not expressing Sonic hedgehog, then the pancreas will grow uncontrollably up to three times its usual mass with much more pancreatic islets than usual, thus impairing the normal functioning of the tissues around it including the stomach and duodenum. They also found that Indian hedgehog plays a different role than Sonic, in that it is required for normal growth rather than repressing growth. In organisms where Sonic was absent along with Indian, there was no observed abnormally large growth, as seen when Sonic was absent but Indian was present. Finally, it was also concluded that without Patched 1, the pancreas is unable to maintain glucose homeostasis.


2. Identify the embryonic layers and tissues that contribute to the developing teeth.

The developing teeth are composed of neural crest-derived mesenchyme and ectoderm from the first pharyngeal arch. Inductive processes occur between these two embryonic tissue types at week 6 to produce the first sign of teeth (teeth buds) in a process known as odontogenesis.[12]


Lab 10 Assessment

To be added after practical.


Lab 11 Assessment

Identify a recent research article (using the pubmed tags to cite) on iPS cells and summarise in a few paragraphs the main findings of the paper.

A recent research article on induced pluripotent stem (iPS) cells is one entitled iPS cells reprogrammed from human mesenchymal-like stem/progenitor cells of dental tissue origin from Columbia University, New York, in 2010.[13] The article acknowledged the usefulness of iPS cells in medical treatments and therapies but noted that human sources of precursor cells to be induced are limited to only a few types, notably dermal fibroblasts on which the original studies were carried out. The paper investigated a new source of human iPS cells - cells derived from dental tissue.

Such dental tissue is readily available through the deciduous teeth lost in childhood and the third molars which are commonly removed in adulthood. Using ectomesenchyme derived cells from such dental tissue, they were able to induce pluripotency in the cells using either the four factors Lin28/Nanog/Oct4/Sox2 or c-Myc/Klf4/Oct4/Sox2. The iPS cells that were produced exhibited a morphology indistinguishable from human embryonic stem cells, and the paper concluded that dental tissue serves as an excellent alternative resource for generating iPS cells.

References