Lab 1 --Z3333794 10:59, 25 July 2012 (EST)
Lab 2 --Z3333794 10:02, 1 August 2012 (EST)
Lab 3 --Z3333794 10:10, 8 August 2012 (EST)
Lab 4 --Z3333794 10:04, 15 August 2012 (EST)
Lab 5 --Z3333794 09:49, 22 August 2012 (EST)
Lab 6 --Z3333794 10:07, 29 August 2012 (EST)
Lab 7 --Z3333794 10:07, 12 September 2012 (EST)
Lab 8 --Z3333794 10:04, 19 September 2012 (EST)
Lab 9 --Z3333794 10:01, 26 September 2012 (EST)
Lab 10 --Z3333794 10:01, 3 October 2012 (EST)
Lab 11 --Z3333794 18:54, 10 October 2012 (EST)
Lab 12--Z3333794 10:12, 17 October 2012 (EST)
Full lab attendance logged. --Mark Hill 07:40, 18 October 2012 (EST)
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.
The roots of InVitro Fertilization (IVF) and Embryo Transfer (ET) dates back to the early 1890s where Walter Heape a dedicated professor and physician at the University of Cambridge in England whereby he reported the first case of embryo transplant in rabbits. He then went on to do more research in the field of reproduction on a variety of animal species. IVF history
IVF worldwide also articulates that the first in vitro fertilization of human oocytes was carried out in 1965 in John Hopkins Hospital, USA by Edwards and Jones and the first IVF pregnancy occurred in 1973 in the Melbourne, Australia by researchers Wood and Leeton. The pregnancy led to a miscarriage and the first IVF baby was born in England on 25th July 1978, 5 years later. IVF history
The 2010 Nobel prize in Physiology and Medicine was awarded to Robert G. Edwards for development of in vitro Fertilization. His contribution to embryology made a worldwide impact as it became a viable way to overcome infertility. [Nobel Prize Winner 2010]
Identify and add a PubMed reference link to a recent paper on fertilisation and describe its key findings (1-2 paragraphs).
In Vitro Fertilization technology has not only impacted humans as a way to overcome infertility but has majot implications for the animal society as well. It is used in breeding practices throughout the world to breed the best quality animals. To make sure the treatment is cost effective it is imperative that the process of IVF leads to a successful pregnancy and as a result birth. Research carried by Jimenez et.al., 2011 focuses at investigating the link between thickness of zona pellucida fertilization, embryo implantation and birth. By using video chromatography their team successfully concluded that the thickness of zona pelucida greatly impacted the fertilization process and transplantation but did not significantly impact in birth.
<pubmed> 22607772 </pubmed>
Mark Hill - Q1 good answer. Q2 You could have mentioned "in the rabbit". 10/10
Adding an Image with the class
Online Lab Questions
Upload an image from a journal source relating to fertilization or the first 2 weeks of development.
Identify a protein associated with the implantation process, including a brief description of the protein's role.
The Rac-1 protein [] belongs to a family of small GTPase binding protein called the RAS superfamily. This protein plays an important role in various cellular processes like cell motility, cellular growth, cell cycle and also cell-cell adhesion. Studies done by Grewal et.al., 2008 demonstrate that the invasion of the human embryonic tropoblast layer into the human endrometrial stromal cells requires mediation by the Rac-1 protein. Increased motility of the stromal cells increases the chances of implantation and an increased expression of Rac-1 activation corresponds with increase in motility. Rac-1 also works by down-regulating RhoA protein which is also important to promote embryo invasion. Since, successful implantation is imperative for pregnancy and fertility the role of Rac-1 is somewhat central to the process of implantation.
<pubmed> 18838676 </pubmed>
Mark Hill - Q1 Image and information provided. Q2 paper relates to implantation. 10/10
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 defined as the time period between conception and birth. It helps the clinicians determine how far along a women is in her pregnancy and is taken from the first day of the women's last menstural cycle (LMC). This is measured in weeks with a normal pregnancy lasting between 38-42 weeks. [Plus - Gestational Age]
Post fertilization age on the other hand is the time lapsed after the sperm enters the oocyte and cell division begins.
Gestational age is used as opposed to post fertilization age as it is easy to determine when the woman had her last menstrual cycle whereas the exact day/time of fertilization is hard to determine. Gestational age is easy to determine both before and after birth. While the foetus is growing it's size of the head, thigh bone and abdomen can be used to establish the gestational age. After the birth the length, size of the head, weight and other vital signs can be used to determine gestational age. Babies born before 37 weeks are said to be premature whereas after 42 weeks are post mature.
Clinically the infant's medical history and medical plan is determined based on the gestational age.
Identify using histological descriptions at least 3 different types of tissues formed from somites.
Histologically somite differentiate into dermis, cartilage and muscle.
The ventral medial portion of the somite becomes the sclerotome via Sonic hedgehog signalling mechanism. Transcription factor Pax 1 then converts the sclerotome into cartilage tissue imperative for the functioning of the vertebrae.
The dorsal portion of periaxial mesoderm is the dermatome which in response to factor neurotropin 3 changes into the dermis.
The medial portion of the somite expresses Wnt1 and Wnt3 factors that converts the myotome into expressing muscle related genes. Similarly Wnt proteins and bone morphogenetic protein 4 (BMP4) cause the expression of muscle related genes in the lateral portion of the somite.
Mark Hill - Q1 2 weeks difference. Q2 3 tissues described. 10/10
Identify the 2 invasive prenatal diagnostic techniques related to the placenta and 2 abnormalities that can be identified with these techniques.
Chronic Villus Biopsy (CVB) or placental biopsy which involves use of a catheter through the cervix or transabdominal needle into the uterus in order to obtain placental tissue. Since the placenta is derived from the cells of the embryo it contains the genetic material of the foetus which can used for chromosomal analysis. The test is performed within 10-12 weeks of pregnancy and can be used to identify a range of genetic mutations (although not all) like Down's syndrome and Turner syndrome.
Amniocentesis is another invasive technique in which a needle is used to obtain a sample of the amniotic fluid via passing it through the mother's abdomen. It is normally performed between 14 to 20 weeks of gestation and is also used to account for any genetic abnormalities. The amniotic cells can be examined either by fluorescent techniques or by culturing them further. Along with chromosomal anomalies this procedure can also be used to diagnose for congenital metabolic diseases, neural tube defects, hereditary related genetic diseases like cystic fibrosis etc.
<pubmed> 16533654 </pubmed>
Identify a paper that uses cord stem cells therapeutically and write a brief (2-3 paragraph) description of the paper's findings.
<pubmed> 19156219 </pubmed>
Type 1 diabetes is a form of autoimmune disease involving destruction of beta cells of the pancreas which produce insulin that helps in maintaining glucose homoeostasis in the body. Deficiency of insulin causes an elevation in glucose levels of blood and urine. Normal treatment of insulin involves insulin injections which is administered daily to the patient. Although the treatment helps to replace the lost insulin it does not solve the autoimmunity problem. Studies done by Zhao et.al., 2009 indicate that using human cord blood stem cells in non obese diabetic mice helps to fight hyperglycaemia and helps restore original architect of the islets of langerhans by causing beta cell regeneration, increase in mass of beta cells and production of insulin.
By using immunostaining techniques showed that the diabetic rats that were untreated had around 80% of their beta cells destroyed whereas the diabetic rats that were treated with cord blood stem cells had a high proliferation rate of beta cells hence proving to be promising therapeutic agent to treat type 1 diabetes. Human cord stem cells can prove to be a viable treatment for type 1 diabetes as it does not involve any immune problems nor does it attract any ethical controversies. There is also a large resource available for cord blood worldwide.
Mark Hill - 10/10
Working on group project
Provide a one sentence definition of a muscle satellite cell (b) In one paragraph, briefly discuss two examples of when satellite cells are activated ?
Satellite cells are a small population of quiescent muscle stem cells that reside in the skeletal muscle.
Short bursts of resistive activity or physical injury that causes chronic stress to the muscle can induce a hypertrophic response and recruitment of satellite cells. Since the integrity of satellite cells is maintained by the intactness of basal lamina any interruption during muscle trauma causes the cells might proliferate the adjacent myofibres. The cells can also travel via chemotaxis to the site of injury. After injury macrophages are recruited to the site as a result of immune response. These macrophages release a number of cytokines essential for recruitment, proliferation and differentiation of the satellite cells.
In one brief paragraph, describe what happens to skeletal muscle fibre type and size when the innervating motor nerve sustains long term damage such as in spinal cord injury?
Long-term injury of the spinal cord damages the innervating motor nerve thus removing the connection between the nerve and the muscle thus depriving the muscle of various neurotropic factors. Over long term, atrophy develops as a result of disuse of the muscle causing degeneration of the myofibril and decrease in the number of satellite cells. Studies have found a decrease in the percentage of satellite cells to as low as 1% following an 18 month old nerve injury. Neurotropic factors are important for providing the growth factors for maintenance of the satellite cell population and denervation negatively impacts its function. After a period of prolonged denervation even if the nerve sprouts back the muscle cannot regain its lost function due to decrease in the reserve pool of satellite cells.
Mark Hill - Q1 OK, Q2 fibre type? 7/10
Critical analysis of group projects
Group 1 - Vision
- the opening is very catchy with the diagram
- good brief introduction although it might help to give a brief description of the different parts.
- Since you have no other tables maybe put the history section in the table so it breaks up the text.
- It might be better to make the images a little bigger so we can see the labels. Also with the images for ‘formation of primary optic vesicles’ you might want to fix the way it’s laid out on the page --- may be put it in a table with a description of what each labelled part contributes to. Also there is no description bellow the pictures either. All the pictures in the development area looks very clustered so break it up with text.
-Large section of the optic nerve development ad retina development seems to have no references. But a lot of good detail is present which shows that you have researched. Although try to use articles rather than books.
- The student drawn images have tiny labels so fix that up maybe and also add copyright information.
- Fig 4 and 5’s formatting should be fixed so they are either side to side or broken up by text. Same goes with fig 6 and 7 – needs copyright info.
- In the current research section a detail of what the research is about and how it is helpful can be given.
- Try using less websites and more journal articles.
- Sections of ciliary body, iris and lens development could use some more detail. The section on iris has the development time in months…it will be beneficial if you kept it in weeks to be consistent with the rest of the parts. The section on lens, aqueous chamber and cornea doesn’t have any development time associated with it which might be useful too.
- I’m aware that you cant do abnormal section in detail but you can still mention some abnormalities in a section without going into heavy detail.
Overall it is a good page but formatting of the pictures and their placement has to be fixed. Some more text should be added to the development section of iris, lens, eyelids etc.
Group 2 - Somatosensory
- The introduction is small yet detailed --- I like how its an overview of the development. You do need to fix up the references though.
- You have in the intro section “the following picture….” But there is no picture there….if the picture is further ahead maybe write Fig 1 shows….and also label the picture.
- History section needs a bit work on – you should start with the earliest data and proceed in a chronological order so everyone can see the advancement in development of somatosensory organs.
- In the section of “Development of the primary somatosensory cortex” you have mentioned that there are intrinsic and extrinsic mechanisms --- you should mention what those signalling mechanisms are. Also if you are using the one ref for the whole paragraph do not put the ref after each line. Just put it in the end. Also it would be good to give the origin of the neurons like ecto, endo or meso. - Its good how your description is divided into stages – it might help to give the weeks as well.
- For the touch section you have a lot of detail on what the receptors are which is fine but there is nothing about their development (which is what the project is about). The same thing is noted with “Pain” section – there is nothing on development. I’m sure you can put some genes or signalling molecules that are important for differentiation of cells into the different receptors.
At the moment your project is focused on what the different somatosensory receptors do but very little detail on how they develop, which is what you need to focus on. More pictures are needed to break up the text.
Group 3 - Olfaction
- The introduction of taste is very descriptive and encapsulates the anatomy, physiology and cell biology. Although it is very detailed it doesn’t indicate that the project is about development.
- There is a lot of detail about the taste neural pathway and cortical areas which I’m not sure is relevant to olfactory development unless you mention how they develop as well.
- Figure 2 and 3 do not have any copyright information associated so remember to add those.
- The development section is very nicely put together and hopefully you will add images further down the line. I’ve noticed that in week 8 of development you have the same ref after each line…I’m sure you can just put it at the end of the paragraph as it is same for each line. Same goes for week 14 and 15. Also since you have 2 references for the entire section --- you might want to look at other articles as well.
- Some things that I missed in the section were patterning molecules and genes. Also any signalling mechanisms that control differentiation.
- The history section is exceptionally done with the use of tables, description and references.
- I thoroughly enjoyed your abnormality section. The images are nicely done as well. Although you have described many genes and molecules which are not specified in the normal development portion so the reader don’t understand their roles. Maybe address this in your normal development section.
- The current development section is also very nicely put together but again things like Shh and WNT should be in development section.
Overall very nicely put together and great balance of pictures and text. Although this is a development topic so the major emphasis should be on development of the organ --- Normal development is good but there is too much content in that section that can be left out.
Group 4 - Olfaction
- The introduction is very good and brief --- although it does not tell the reader that it is about development of olfactory sense.
- The history section is immaculately done --- You have used a couple different sources and gone into enough detail about each historic background which tells me that you have thoroughly research this part.
- The development section is also very nicely done --- I like the layout of this section. Also the sentences are very clear and structure is easy to follow. There is a large section in week 6 which does not have any reference so you might want to fix that up. Same goes for week 7 abd week 8.
- When you start talking about anosmia it just abruptly follows normal function so you might want to add the heading “abnormal development”. It might even be a good idea to put normal function before normal development to put things in perspective.
- In Kallmann’s syndrome although it was very interesting to read, it is very heavy on genes which you have not addressed in the normal section portion. I do realise for some of them you have put a description as to what they do in normal development but see if you can integrate it with normal development too.
- It is also good to see that you have a diagnosis section and a treatment section too. It was very informative.
- Current research is well put together
Overall your project is looking pretty good….Just some minor formatting issues. The text is a little on the heavy side some pictures especially in the development section will be good.
Group 5 - Abnormal Vision
- A very good start to the page with the introduction. It gives an overview of the page and is very nicely done --- an image in the beginning will make it more effective. Right now the starting is very text heavy so an image will not just tone it down but will have a more profound impact.
- Normal eye development is good too but just to make the text look not so heavy you can consider putting it in a table like a brief summary.
- Traditionally research timeline should go on the top of the page but I don’t think it’s a big issue. Again you should consider tabulating it so it looks not so text heavy.
- I like how you talk about each part of the eye and different genes. You have a range of articles which also seems great and shows how much effort you have put in.
- Research section is not so extensive so far so you might want to work on that.
At the moment the organisation of the page is not great and it is very text heavy. Even though there are many images on the page it still looks very text heavy. Adding tables might help breaking that up and also add make the page look bright.
Mark Hill - Excellent 10/10
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.
Study performed by McDonald and colleagues was aimed at establishing the role of Sox9 gene during human foetal pancreatic development as it was earlier shown to play an important role in the development of mice pancreas. The pathological hallmark of diabetes is the reduction in the number of insulin producing beta cells and the aim of many stem cell therapy is to replace these lost cells. However in order for the progenitor cell to correctly differentiate and proliferate into beta cells correct signalling mechanisms are essential. By immunehistochemistry studies and western blot analysis it was confirmed that Sox9 is expressed in human foetal pancreas as early as week 8 and is highly expressed till week 20 and then rapidly declines. The study also confirmed that knockdown of Sox9 gene significantly lowers the number of cells that express beta-cell markers thereby indictaing the importance of Sox9 in development of human pancreas.
Identify the embryonic layers and tissues that contribute to the developing teeth.
The development of teeth encapsulates cells and tissues that are ectodermic, mesodermic and neural crest in origin. The enamel of the tooth is derived from the ectoderm. Majority of the dental pappilae and various tooth cell types including odontoblasts, osteoblasts, cementoblast and fibroblast are neural crest in origin whereas some dermal papilla are found to be derived from the mesenchyme. These cells contribute to the formation of the blood vessels located in the pulp of the teeth.
Mark Hill - Excellent 10/10
Finishing off group project
Stroke and ischemic brain damage is the second leading cause of death in Australia with the current tPA therapy not being very effective. Use of stem cells offers a new avenue for treatment of stroke but due to ethical issues and the ability of stem cells to be teratogen and cause immune problems it is hard to bring the research into practice. Induced pluripotent stem cells offer a great therapeutic tool for treating stroke as the possibility of immune rejection and ethical problems can be completely discarded.
A study performed by Oki et.al. (2012) used human IPSCs which were transformed into neuroepithelial-like stem (lt-NES) cells. The Human IPSCs were reprogrammed using the factors Oct4, Sox2, KLF4 and c-MYC. Ones the cell lines for human-IPSCs were established certain factors were used to transform them into neurons like stem cells. One week post transplantation a marked increase was observed in the behavioral tests. Using immunohistochemistry they established that lt-NES cells produce factors like VEGF and BDNF that increase angiogenesis and functional and structural plasticity of the brain.
Mark Hill - 10/10