Lab 1 - Z3292017 10:15, 25 July 2012 (EST)
Lab 2 - Z3292017 10:17, 1 July 2012 (EST)
Lab 3 - Z3292017 10:13, 8 August 2012 (EST)
Lab 4 - Z3292017 11:23, 15 August 2012 (EST)
Lab 5 - Z3292017 10:34, 22 August 2012 (EST)
Lab 6 - Z3292017 11:31, 29 August 2012 (EST)
Lab 7 - Z3292017 10:14, 12 September 2012 (EST)
Lab 8 - Z3292017 10:13, 19 September 2012 (EST)
Lab 9 - Z3292017 11:11, 26 September 2012 (EST)
Lab 10 - Z3292017 11:06, 3 October 2012 (EST)
Lab 11 - Z3292017 10:05, 10 October 2012 (EST)
Lab 12 - Z3292017 10:37, 17 October 2012 (EST)
Full lab attendance logged. --Mark Hill 07:43, 18 October 2012 (EST)
Lab 1 - Z3292017
Lab 1 Online Assessment
Question 1: Identify the origin of In Vitro Fertilization and the 2010 nobel prize winner associated with this technique:
The origin of IVF can be dated from the late 19th Century where embryo transplantation in rabbits was discovered by Walter Heape. The development of IVF was due to a cascade of events during the 20th century. Pincus and Enzmann from Harvard University suggested the possibility that mammalian eggs are able to develop normally in vitro in 1934. In 1948 Menken and Rock exposed 138 oocytes to spermatozoa in vitro. In 1959, Change was able to provide evidence for IVF by fertilising rabbit eggs with capicated sperm and thus achieve birth. From 1965 Robert Edwards attempted to fertilise human oocytes in vitro. In 1968 Edwards successfully fertilised a human egg using a human culture media he developed. Finally after years of research and failed attempts, the first test tube baby was born in 1978. Robert Edwards was awarded the Nobel Prize in Physiology and Medicine in 2010 due to his immense development and contribution of IVF.
Question 2: Identify and add a PubMed reference link to a recent paper on fertilisation and describe its key findings:
Cleavage speed and implantation potential of early cleavage embryos in IVF or ICSI cycles by Lee, Lin and Hwu (July, 2012) attempted to determine the correlation of early embryo cleavage, its speed and the potential implantation rates for IVF. Their definition of early cleavage was embryonic mitosis occurring 25-27 hours after insemination. The embryos’ (day 3) cleavage speed was assessed and rated into 3 groups: rapid (more than 9 cells), normal (7-8 cells) and slow (less than 7 cells) along with their morphological quality being either good or poor. Normal fertilisation was determined by the presence of 2 nuclei and 2 polar bodies. 25-27 hours after IVF an early cleavage examination took place to determine which embryos had already cleaved. They embryos were then examined for their quality from 66-68 hours after IVF.
Early cleavage emrbyos developed normally in comparison to non early cleavage embryos. Notably, the early cleavage embryos produced a greater amount of “good quality” embryos and subsequently the implantation rate was sufficiently greater with early cleavage embryos. This finding is of great importance as embryo morphology is the most important tool to select the best embryo to transfer andthus increase the rates of implantation, pregnancy and live birth.
Lee MJ, Lee RK, Lin MH, Hwu YM Cleavage speed and implantation potential of early-cleavage embryos in IVF or ICSI cycles. J Assist Reprod Genet. 2012 Jul 25 PMID: 22825967
Mark Hill - You have answered both questions well. The second question should have followed the PubMed citation method that I gave a tutorial on in class, alternatively removing the colon from your PMID: 22825967 to PMID 22825967 would generate the correct link, but not the automatic formatting. 9/10
Lab 2 - Z3292017
Lab 2 Online Assessment
Question 1: Image from journal source
Zygotes showing different distribution of NPB in the 2PN and different PB alignment 
- Alessia Nicoli, Francesco Capodanno, Lucia Moscato, Ilaria Rondini, Maria T Villani, Antonella Tuzio, and Giovanni B La Sala (2010) Analysis of pronuclear zygote configurations in 459 clinical pregnancies obtained with assisted reproductive technique procedures Department of Obstetrics and Gynecology, Arcispedale Santa Maria Nuova, Reprod Biol Endocrinol. 2010; 8: 77. NCBI
Question 2: Identify a protein associated with the implantation process, including a brief description of the protein's role
Proprotein convertase 6 (PC6) is a necessary regulatory molecule for embryo implantation which generates bioactive proteins such as growth factors, peptide hormones and adhesion molecules. It is produced in the uterine stromal cells in particular at the embryo attachment site throughout early pregnancy in mice. In order for implantation to occur, the uterus ungergoes morphological and physiological changes, one being differentiation of endometrial stromal cells.
Studies have shown that PC6 mRNA is upregulated in particularly at the site of embryo attachment in the mouse uterus, being predominantly at the antimesometrial pole undergoing decidualisation. These results imply that PC6 is associated with decidualisation. From this study, the researchers were able to determine that endometrial PC6 is imperative for maternal stromal decidual response for an implanting embryo during the time of implantation. They discovered that endometrial PC6 is produced explicitly in decidual cells (the vascular and cellular changes in a uterus in preparation for pregnancy) and is not found in other cells as well as the embryo. Similarly, they noted that inhibition of the production of PC6 early on (around day 3.5) using anti-PC6 MO blocked the decidualisation and thus impeded implantation. Notably, PC6 is produced in the late secretory phase of the menstrual cycle in preparation for implantation.
Guiying Nie, Ying Li, Min Wang, Yi Xun Liu, Jock K. Findlay and Lois A. Salamonsen Inhibiting Uterine PC6 Blocks Embryo Implantation: An Obligatory Role for a Proprotein Convertase in Fertility Biology of Reproduction April 1, 2005 vol. 72 no. 4 1029-1036. Biology of Reproduction
Mark Hill - Both questions answered correctly, I don't understand why you use the citation link correctly on the image page but not here in your answer. Did you also not get a warning that the image you used had been previously uploaded by someone else (02:54, 7 August 2012 Z3289738), though not as important for this exercise. 9/10
Lab 3 - Z3292017
Lab 3 Online Assessment
Question 1: Difference between post fertilisation age and gestational age
Post fertilisation age (embryonic age) is dated at fertilisation of the egg which is approximately 2 weeks after the gestational age. This however is far less easy to determine than the gestational age as they calculate the time of ovulation as the oocyte is normally fertilised within the 12 hour period after ovulation.
Gestational age is the date of the beginning of the last normal menstrual period and is clinically more commonly used as it is a much easier method to calculate. Notably, the crown-rump length of the fetus along with the head and femur length are later used to confirm the estimated age of the fetus.
Question 2: 3 different types of tissues formed from somites
Ventromedially, the somite differentiates into the sclerotome which forms the vertebrae and the ribs. Studies have shown that Pax-1 is essential for the ventral sclerotome differentiation. The sclerotome differentiates into the vertebrae and ribs through bone formation. Role of Pax-1 in skeleton development. This is primarily initiated with mesenchymal cells which assists the formation of the pre-cartilage mass via chrondrocytes and subsequently cartilage formation. Bone then develops through the replacement of cartilaginous tissue with bone tissue. Development of bone and cartilage
Dorsolaterally, the somite first differentiates into the dermomyotome which then creates 2 regions. The myotome region forms primordial muscle cells (myoblasts) and the dermatome region forms the fibroblasts (dermis). Development of Muscle
Dermatome along with Neurotrophin-3 assists with the early formation of the dermis. Role of Neurotrophin-3 The dermal papillae consist mainly of fibroblasts and is located close to the epidermis. It contains both elastin and collagen fibres (produced by fibroblasts) with the elastin fibres perpendicular to the surface of the skin. The reticular dermis accounts for the majority of the dermis with multidirectional elastin and collagen fibres. Notably, in the dermal papillae, a plexus consisting of numerous blood vessels are found but do not penetrate into the epidermis. Some nerves within this region do penetrate through to the epidermis via free nerve endings which are linked to nerve corpuscles, such as Meissner's plexus. Dermis formation
Myotomes are separated into epaxial muscles and hypaxial muscles via primordial muscle cells . The epaxial muscles form the skeletal muscles dorsal to the vertebral column known as the erector spinae muscles. The hypaxial muscles form the ventral skeletal muscles which contribute to the lung and limb formation. The skeletal muscle fiber is long, cylindrical and multinucleated, with peripherally located nuclei.
Mark Hill - Both very good answers to the 2 questions. Note that you could have used an internal link format in the Myotome answer. 10/10
Lab 4 - Z3292017
Lab 4 Online Assessment
Question 1: 2 invasive prenatal diagnostic techniques related to the placenta:
A relatively common yet invasive procedure normally conducted between weeks 15-18 of gestation. A 22 gauge needle is inserted through the anterior abdominal and uterine walls (around the region of the umbilicus) of the mother into the amniotic cavity. Of the approximate 200mL volume that the mother is carrying at this early stage of pregnancy, only 15-20mL can be withdrawn safely. There is usually little risk when performing this procedure as an ultrasonography can be used concurrently to outline the fetal and placental position.
Amniocentesis is a procedure used to determine many genetic disorders such as Down Syndrome and also neural tube defects such as spina bifida cystica. Amniocentesis - The Developing Human
2. Chorionic Villus Sampling:
Trophoblastic tissue biopsies between 5-20 mg can be obtained through inserting a needle through the abdominal and uterine walls of the mother into the uterine cavity. This can also be completed transcervically using a polyethylene catheter through the cervix to obtain a chorionic villus sample. There is a slightly greater risk of miscarriage after this procedure has been performed when compared to amniocentesis (of around 1%).
Chorionic villus sampling is a procedure used to detect chromosomal abnormalities and also X linked disorders. The benefit of CVS over amniocentesis is that it can be performed between the 10th-12th week of gestation and thus giving an earlier diagnosis. Chorionic Villus Sampling - The Developing Human
Question 2: Paper using cord stem cell therapeutically discussion of findings:
Lim JY, Jeong CH, Jun JA, Kim SM, Ryu CH, Hou Y, Oh W, Chang JW, Jeun SS Therapeutic effects of human umbilical cord blood-derived mesenchymal stem cells after intrathecal administration by lumbar puncture in a rat model of cerebral ischemia Stem Cell Res Ther. 2011; 2(5): 38 PMID: 21939558
In this paper, the researchers investigated the effects of therapeutic potential of mesenchymal stem cells after intrathecal administration by lumbar puncture in a rat model of stroke. Following this, the researchers then investigated whether the mesenchymal stem cells could enter and survive in the brain, and their potential to improve post stroke functional recovery. Mesenchymal stem cells (MSC) are a promising therapeutic strategy for the treatment of stroke due to their high proliferative capacity and also that they can be easily obtained.
The mesenchymal stem cells were injected intrathecally in some rats and intravenously in the others three days after Middle Coronary Artery Occlusion (MCAO) using isoflurane anesthesia. A 1cm incision was made over L3-L5 spinous processes and a neonatal lumbar puncture needed (25 gauge) was inserted into the spinal canal. MSCs (1 × 10^6) was diluted with 20 μl PBS being injected into the CSF over 30 seconds. Intravenously, MSCs (1 × 10^6) was diluted with 700 μl PBS were injected slowly for five minutes via an intravenous cannula situated in the tail vein. The presence and survival of the MSCs in the brain tissue was examined by immunohistochemistry. The rats were examined by their recovery of coordination of movement using both the Rotarod test and the adhesive removal test after the 1st, 2nd, 3rd and 4th week of stroke.
The results indicated that the MSC intrathecally receiving rats had an increased level of migrated cells to the ischemic area compared to the intravenous administration of MSCs. Additionally, many of the cells were expressing the mature neural lineage markers. Overall, the intrathecal administration of MSCs were more effective in reducing ischemic damage, yet proved to be similar to intravenous administration in promoting neurological recovery.
This study thus indicated a potential treatment for cerebral ischemia or neurodengerative disorders due to its ability to recover ischemic damaged tissue.
Mark Hill - Good answers to both questions. You should not though directly copy content from other sites, you should make the effort to write your answers in your own words, if it is a direct use (even if cited) it should be contained within quotation marks. You still seem to be having trouble using the correct citation formatting in question 2, see me if I can help. 9/10
Lab 7 Online Assessment
(a) Definition of muscle satellite cell
A muscle satellite cell is a quiescent mononucleated cell, which respond to injury by proliferating to form regenerated muscle and additional satellite cells, found between the basement membrane of specialised muscle fibres. Muscle Satellite Cell PMID: 12757751
(b) Two examples of when satellite cells are activated
Satellite cells are employed for skeletal muscle trauma and also disease.
- Muscle injury: When muscle injury occurs, the satellite cells are activated and will either form multinucleated myotubes to assist with muscle regeneration, or will form additional quiescent satellite cells in order to assist with more muscle regeneration. Sambasivan et al. indicated in their 1993 study that other cells with regenerative potential depend on the satellite cell presence especially the Pax7 expressing satellite cells. Pax7-expressing satellite cells
- Muscle disease: Research has shown that congenital myopathies such as Duchenne Muscular Dystrophy lead to a greater number of satellite cells than in normal muscle cells. Notably, the regenerative capacity of, for example Duchenne Muscular Dystrophy, is limited due to the severity and continuation of the disease. Muscle stem cells in development, regeneration, and disease
Question 2: 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
Spinal cord injury will result in partial or complete paralysis of the muscle innervation at or below the trauma level of the spinal cord resulting in atrophy. Some studies have noted that a some paralysed muscles due to spinal cord injury have an increase in force per cross sectional area of the muscle compared to normal in an attempt to maintains the muscle's normal strength. However, it is also important to note, the muscle cross sectional area significantly decreased. Due to the decrease in muscle, the study also indicated that there were increased levels of connective tissues and fat - thought to transfer more of the force to the tendon. Importantly, in chronic muscle denervation (greater than 50% of muscle size loss), the strength of the muscle (if there was any at all) has seriously deteriorated. Muscle Atrophy after Human Spinal Cord Injury
After a spinal cord injury the muscle fibre type pattern changes from a mix of type I and type II to predominantly type II fast glycolytic fibres. This is thought be an explanation of the quick muscle fatigue noted in rehabilitation. Notably, Burnham et al. discovered that the muscle fibre type change occurs in stages rather than an immediate effect and thus opens the door to more research to prevent the transformation of the muscle types from occurring, which is inidcated to be done within the first week or two following spinal cord injury. Skeletal muscle fibre type transformation following spinal cord injury
Mark Hill - Very good 10/10
Lab 8 Online Assessment
The photo at the top of your page is a great choice and makes the site that much more appealing. The only suggestion I would have here is to potentially minimise the photo as it makes the contents section to the left of it hard to read. Your introduction is clear and concise and gives a good description of the eye. A slight adjustment I would make is perhaps to make it slightly longer giving a brief discussion about what is to be discussed on this page. Included in your introduction you have the anatomy of the eye. Firstly, would it be appropriate to include the histology as well, as it appears further down the page you discuss the cells, so perhaps if you gave a brief histological overview that could make the sections below easier for the reader to comprehend. I would probably add to that that if you were to include histology, to put the anatomy and histology into a new section just so it doesn’t clutter the introduction.
Your history, although I’m aware it ins’t finished, would read better if it were in a table and would also bring some more colour to the page. I’m assuming this will come when you finish this section, but it would be wise to include updated examples as well in order to show an adequate progression of the history.
The development section appears to be very thorough which is fantastic. It is rather clear that you have put a lot of research and time into this section. The introduction you have there is well written and again concise which is great. Additionally I like your use of photos just below it to further your explanation and also to break up the text. In regards to your photos, I would suggest perhaps a better description of them and to make sure you include where you got the photo from. If there were an explanation of the photo in simplistic terms, then I think the photos would be really beneficial.
The optic nerve section is well written but it appears to lack references?? In the first 3 paragraphs there are only 2 references. I would probably suggest that this information is backed up by additional sources as well. Also, with your hand drawn pictures (which are good), I would suggest an explanation on them when you open the picture up in another window. Your paragraph describing the 2 pictures, I would probably recommend that it become sintegrated within the text i.e. when you are talking about that part of it then include it there. I just think it would make it flow better that way – like you have done with figure 3.
The retina is good and well set out with pictures. However I noticed that you have used the exact references as before (3, 4)?? It would be really advisable to include many more references than what is listed. The same applies to the images as I said above, but good integration!
The ciliary body appears to be well researched and referenced. From the iris down there appears to be a lack of new references and also looks rather bland - so here I would suggest including additional photos from journal articles you have used. Also, it seems rather brief, I’m wondering whether there is more information about the embryological processes that could be included?
The current research is a good start, but there isn’t much of an explanation of the photo that is included and brief discussion of the research should probably be included. Are there additional research projects to include as well?
Finally, your references ar good but short. The fisrt 2 need to be put in the appropriate format. I would definitely suggest including many more references in order to make your information listed more valid.
I really like your introduction, I think that is is really informative and gives the reader a much clearer understanding of what this topic is about. Your references here need to be included in the reference section below but it appears that you have a good amount of references for the points depicted. At the end of the first paragraph it discusses a picture of the general organisation however there is not one there?? Also the inclusion of a picture would be agreat idea not only to further our understanding but also to break up the text and make it more appealing.
In your history of discoveries section I would probably recommend putting this in a colourful table, again to rbeak up the text, and also to make it easier to read. I would probably suggest here that you include a greater progression of discoveries to show the change of thinking over time. Note to also inlduce the appropriate referencing as shown in previous lab classes.
The central somatosensory differentiation is very expansive and informative. I would assume that you have put a lot of research into this section. Note that you have used pretty well the same references over and over. I would suggest that you include additional references to back up those statements as well. If those couple of references were the only ones saying that information, then I would suggest further researching to ensure that other journal articles don’t contradict this. The image is good and appears to show a good somatosensory pathway, however I would make the font bigger, so that it would not be imperative to enlarge the photo to read what is there. The picture has a discription when it is enlarged which is good, but I think it would also be appropriate to put the correct student information for the referencing.
In the Touch part, I noted that almost none of the text is refenced, which essentially makes the information listen invalid, so I would look into finding appropriate references here. Also, this section seems a bit dull with no pictures. Perhaps histological photos could be included here? I know we studied them in histology and this would make the section more interesting and also compliment the information stated. I would also suggest that those subheadings you don’t want in bold, you list in italic with two ‘ ‘ in order to separate it from the text below..
The Pain section probably needs to be set out better by using dot points? It appears that you have provided some excellent information but it is also important to put the references included with the reference section below. A photo here might be nice, perhaps of the different fibres if this can be found?
The Hot/Cold section is better set out and I like the appropriate referencing here. However, it appears that you are re-using the same references, so I would suggest some more research be done here to compliment your other references. It is better set out, however I would suggest some photos to be included if at all appropriate and can be found.
Pressure is similar to the pain section in the sense that the references really need to be put in the referencing section. It would also be advisable that you split the first paragraph up as it is rather long and not very appealing for one to read.
Current research section is good and concise. I like the use of the picture there, and I like the description that you have when you enlarge the picture. Is there any other current research happening now?
Finally, I would suggest adding more information outlining the development of these areas as I believe this to have been limited across the majority of sections. Although you are providing good reaseach and information describing these sections, as this is am embryology course, I would see it as appropriate that some sort of developmental progression is included – or if this is not known as of yet, for that to be stated. I would also highly recommend that you include a detailed glossary of words, as this is rather incomplete.
The introduction section is very informative and I like the picture included discussing the 5 basic tastes which is interesting to read. I really enjoy your descriptions of bitter and sweet and find it interesting to read. I like the research you included in this section but I believe this needs to be referenced. Currently in the introduction you have only 1 references, so I would suggest that you find more to further validate your information (note that there are no references in the first paragraph). I like in your picture that you included a description. The cell biology section I would probably put in its own section with = = to break up the contend displayed. In this section it is clear that this has been researched however there have been no references listed at all here.
The taste map section has clearly been well researched yet poorly referenced. It would be interesting to look at if possible a progression of the understanding of the taste map. In the picture of the tongue, I would suggest that it has a better description on the enlarged image. However, some of this text is rather hard to read, such as the descriptions of the first and second order neurons. As you have included terms in there which would be foreign to most people, I would try to include either a picture to show exactly where these parts are such as the NTS which can give the reader a better understanding of what you’re saying. Note that you say things like “copious scientific conjecture surrounds…” however there is no references here! This section is well researched which is great, but I would really consider putting it into slightly easier terms to better comprehension.
In the cortical areas section, a similar approach applies: when describing locations of things such as the I/fO, you should really include a clear diagram as to where all of these are. I can see you included the section of the brain however don’t see it as too informative so a better description there would be appropriate. I would also note that you are repeating your references again, and it would be advisable that you find alternative information to include as well.
The timeline section is very informative and really stands out. I’m assuming you will be including the photos later this week. This is well written and gives a truly informative description of the embryological changes that occur. It will look much better and be better to understand once the photos have been included. Note that you have used the same references pretty well the whole time in this section. Although that paper may have a lot of information about what you are needing to talk about, I would also encourage you to research more papers in order to compliment the information you have listed.
The history of discoveries section is well set out and clear and concise. In some areas I would suggest a brief descripton of what you have written such as “PKD2L”, and also make sure you include the appropriate references as all I can see currently it numbers.
In the adult tongue and taste bud section, is this also what the tongue looks like from week 15? If not what changes occurs for it to form into what you have described as the adult tongue and what enhances these changes? This section is informative however it is really lacking references. The taste bud picture you have is quite good, but is that also what the taste bud looks like at 15 weeks?
The abnormalities section is really interesting and is rather enjoyable to read. Are they the only abnormalities that can happen to the tongue? How about environmental? Does alcohol, smoking or drugs affects its development of either the tongue or the taste buds? Additonally, your current research is very thorough and interesting. In regards to the photos you have there, I would make sure that they are set out appropriately, with the information that this is a student project.
Finally, the glossary needs to be highlighted to make it stand out and more words need to be included. Note that in your references, reference 5 can not be accessible, so make sure you fix that up. Overall, it was interesting to read and I enjoyed the display of photos that were also included!
Your introduction is good and concise giving a simple understanding of the olfactory system. Here I would suggest that you include what you’re about to discuss on the page. I also think you should include some references and maybe a photo in this section. The references to show that this information has been researched and the photo to break up the text and give the reader a simple understanding of the olfactory system.
The history of discovery section is clearly well researched and is well set out. However, I would suggest that you include brief descriptions of what has been described such as the Vomeronasal organ or the Nobel Prize which will further enhance the readers understanding. You have a good use of references there as well. In the picture that was included in this section, I would provide a more indepth description of what is drawn i.e. what the ectoderm is etc.
The timeline of developmental process is really well set out and easy to read. I would just make sure that every new point you include, you put it with a references as some of your points are not referenced at all and you need to be careful of that! I would also suggest that you put it in appropriate bullet points using the star key on your keyboard, that way it can be set out a bit better. Also, at the end of week 8, does this mean the olfactory system is complete by then? If so, then I would suggest you state that in that final week, if not, then what other small changes occur throughout the duration of the pregnancy? Also note that week 6 – 8 the references are either limited or not there, so I would recommend putting them in.
The anatomy of the olfactory system and the normal function are limited in information but also have only one reference between them. The images attached should really have more of a description when the picture is enlarged to give the reader a better understanding of what you’re talking about. Such as: diagram of olfactory bulb- what does it do and where is it located?
The abnormality section is rather indepth for 2 conditions, are there any other factors that come into play in regards to olfactory defects? Such as environmental? The Kallmann’s syndrome is really indepth and describes the clinical features, diagnosis and treatment, could this also be implementd with the Choanal atresia? Or are the same techniques used there? Also, be careful when you use shortening of words such as OB, you provided the HH in brackets first, so I would suggest the same is done with the olfactory bulb just to prevent confusion. I like your use of both images and give s a simple but good explanation of what you have been discussing (and also breaks up the text!). I like how you have provided a good description in the enlarged picture and it makes it easier for the reader to understand.
The current research section really shows that you have put a lot of effort in for this section. However, at the beginning of each new research you state either a study or a paper with a link, perhaps use the name of the paper and who wrote it and use that as the link instead. It is really interesting and I rather enjoyed reading it, however, if possible I would add some more photos just to break up the text. Your glossary is good and well set out and the information displayed is quite easy to understand, however I would consider adding to this section as there were some other words throughout the page which were in need of a slight description. You have an excellent use of references which is great, but I would have another look at reference 11 as there is no text, only an arrow.
Your introduction is rather succinct which I like but I would encourage you to put references in this section. I would also suggest that you split it into 2 paragraphs to make it easier to read. Perhaps maybe you could put a photo of a normal eye in this section to show what it should look like, and then throughout the paper as you discuss the abnormal developments, you it could give the reader a better understanding as to how exactly this has altered the eye using the comparison.
The Normal eye development section is good as it provides a way for the reader to compare the differences in progression when referring to the different abnormalities listed below. However I would possibly suggest this to be put in a table, with perhaps a sentence at the top saying something along the lines of in order to fully comprehend abnormal development, an understanding of normal eye development is important - that way the reader can understand why you put this section in. I would also suggest a picture here.
The abnormal lens development section is clearly very well researched with a wide range of references. I like how you have separated the development in to the different sections of the eye as this can give a more thorough insight into these abnormalities. I think this section has been well written, and the only suggestion I would have would be in regards to the photo presented. Perhaps include some arrows to point at the sections you’re talking about and discuss what the nuclear area of the lens is?
The anormal corneal development and the abnormal retinal development are very descriptive and well referenced. I would perhaps look at moving the photo in the corneal development up a bit more and again I would provide more of a description of what is shown. If possible, I would try and make the abnormal retinal photo bigger.
Ocular manifestations is a bit confusing as im not sure if it’s a new heaing all together of if it is supposed to be part of the broad category of abnormalities. Your genetic section is well researched, I would just be careful in referencing the same paper too many times (25 is listed 5 times in this section) and perhaps try and find some other papers which compliment this research? I would probably put your reseach timeline at the bottome and include all of the treatment and clinical manifestation flowing on from each other. Note that in the research timeline, this is purely from one source, reference 26, and I would advise that you find alternative sources as well – im sure there would be individual research papers for each new date??
The anophthalmia section im assuming is still part of genetic abnormalities and I would recommend starting with the genes which are affected – to create a flow on effect. Other than that it is well references and easy to read. In regards to your photo I would have a description of what the photo is about in the enlarged view to assist with the readers comprehension. Also, at what point can these abnormalities be detected in the womb – either from an ultrasound or from sampling of the genes or something - and does this have an affect on whether the mother keeps the child or not? I think the environmental causes of abnormalities are good and I would suggest that you add photos here to break up the text and also to give us an understanding of what happens.
Finally, your glossary needs a fair few more words in there as to help with our understanding. You have many references which is great, however take a loot at 46 – 49 – they all seem to be the same? It would be appropriate to merge them into one reference.
Mark Hill - Good peer feedback on the project work. 10/10
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.
This research paper wanted to determine if Cdk4 has a role in embryonic pancreas development. The study required embryos being harvested from mice (Cdk4+/+, Cdk4–/– and Cdk4R24C) 1 hour after the discovery of the vaginal plug. The results indicated that Cdk4 is needed for growth and morphogenesis of the developing pancreas. Cdk4 deficiency decreases the size of the pancreas due to diminished mesenchyme development and less Pdx1+ cells. The results allude to the fact that Cdk4 promotes the Beta cell growth from the signalling transcription factor E2f1 to assist in the proliferation of Ngn3+endocrine precursors. Cdk4 thus is seen as an imperative regulator of the early developmental stages of the pancreas which regulates the growth of the endocrine precursors and pancreatic progenitors.
2. Identify the embryonic layers and tissues that contribute to the developing teeth
The teeth development necessitates the epithelial/ mesenchymal interaction between the ectoderm of the first pharyngeal arch along with ectomesenchymal cells of the neural crest . The tooth bud is the name given to the collection of cells which will later form a tooth . There are 3 sections which contribute to the developing teeth:
- The enamel organ: The cells of the inner enamel epithelium of the enamel organ form the ameloblasts which differentiates and produces the enamel.
- The dental papilla: This is formed by the neural crest and cells from an unknown origin . These cells develop into odontoblasts (or dentin forming cells). The mesenchymal cells contribute to the formation of the tooth pulp.
- The dental follicle: This produces 3 different cells. Cementoblasts create the cementum of the tooth. The osteoblasts create the alveolar bone around the tooth roots. Finally, the fibroblasts form the periodontal ligaments which attach the teeth to the alveolar bone.
Therefore, the ectoderm, neural crest and mesoderm all contribute to the development of the tooth.
Mark Hill - Excellent answers. 10/10
In this research article, long term expandable neuro-epithelial like stem cells (It-NES) produced from the adult human fibroblast derived iPSCs were transplanted into the areas of stroke in mice and rat brains. Human induced pluripotent stem cells were produced and then were transformed into neuroepithelial like stem cells. The mice and rats incurred a middle cerebral artery occlusion and a week later, the human induced pluripotent stem cells were transplanted intracranially highlighted with a green fluorescent protein. 9 weeks following the transplant of the stem cells, the mice and rats were injected with 2% fluro-gold. Subsequently behaviourable tests along with cell counting and VEGF immunoreactivity took place to determine the effect of the induced pluripotent stem cells.
The results indicated that the transplanted neuro-epithelial like stem cells lead to an improved recovery of the motor deficit. The noted neuronal markers in the graft area at 10 week post transplantation, however they believe that recovery occurred much earlier on due to the progress they saw. This could be due to additional mechanisms working with the neuronal replacement. Notably, behavioural recovery was increased in both the mice and rats regardless if they had been transplanted with the neuroepithelial like stem cells.
The researchers believe that the raised levels of VEGF in the animals with the transplants were found to be important for minimising the inflammation and the neovascularisation in the peri infarct region. The transplanted cells also showed characteristic neuronal morphologies and had markers which showed that they had differentiated into different neuron subtypes. Additionally, through the electrophysical data, the induced pluripotent stem cells indicated they were able to differentiate into functional neurons creating normal connections with the host brain, along with synaptic input from the neurons of the host brain. After approximately 5 months, the transplanted cells showed electrophysiological qualities of normal mature neurons. This article was the first of its kind to show that induced pluripotent stem cells are able to replace sections of a stroke damaged brain.
Mark Hill - Excellent answer. 10/10