lab 1 --Z3331951 11:49, 25 July 2012 (EST)
Lab 2 - Z3331951 10:01, 1 August 2012 (EST)
Lab 3 - Z3331951 10:08, 8 August 2012 (EST)
Lab 4 - Z3331951 10:23, 15 August 2012 (EST)
Lab 5 - Z3331951 10:20, 22 August 2012 (EST)
Lab 6 --Z3331951 10:11, 29 August 2012 (EST)
Lab 7 --Z3331951 10:16, 12 September 2012 (EST)
Lab 8 --Z3331951 10:46, 19 September 2012 (EST)
Lab 10 --Z3331951 10:18, 3 October 2012 (EST)
Lab 11 --Z3331951 11:29, 10 October 2012 (EST)
Lab 12 --Z3331951 10:05, 17 October 2012 (EST)
Lab 1 Assessment
The 2010 Nobel prize was awarded to Robert Edwards for his pioneering work in developing in vitro fertilisation. Details can be seen on this page
An interesting article regarding fertilisation was authored by Eisenberg et al and published in July 2012, titled Sperm counts and sperm sex ratio in male infertility patients. The paper attempts to partially account for the recent decline in male births in some industrialised societies. In order to do this, they have collected sperm samples from both fertile and infertile men. The proportion of X and Y chromosome carrying sperm was them investigated for each of the samples. This is relevant as it is the sperm that determine the sex of the zygote. Eisenberg and his team found that motile and fertile sperm actually have a predisposition to carrying the Y chromosome, indicating that the higher a mans reproductive potential, the greater his chances of having a male child.
Lab 2 Assessment
The endometrial glands secrete fibronectin. This extracellular matrix protein interacts with integrin receptor proteins on trophoblast cells to form a bond. This is one of the initial bonds between the blastocyst and the uterine wall
Lab 3 Assessment
Amniocentesis is an invasive procedure where a needle is passed into the amniotic cavity of the foetus and a collection of the amniotic fluid is taken. Out of this fluid, foetal cells can be isolated and grown for testing. Occurs between 14 and 20 weeks gestation. Chromosomal analysis of the cells can identify the trisomy 18 (Edwards’s syndrome) defect, along with other chromosomal defects.
Chorionic villus sampling uses a catheter to sample cells of the chorionic villi, a key component of the placenta. Similar to amniocentesis, it is primarily used to identify the karyotype of the foetus. An example of a disorder that can be identified with this procedure is trisomy 21 (Downs’s syndrome).
The team of Zhu et al studied the potential use of umbilical cord blood mesenchymal stem cells (UCB-MSC) in the treatment of gastric cancer, which is quite resistant to the classical methods of treating cancer. The procedure used the stem cells as vehicles to deliver signalling molecules to the tumour. This is due to UCB-MSC’s ability to migrate into the site of cancer and begin to proliferate. Using recombination and other methods, the stem cells were engineered to secrete LIGHT, a member of the TNF family of receptor molecules. LIGHT is able to stimulate both antitumour immunity, and also the apoptosis of cancerous cells themselves.
Nude mice were given gastric cancer as a live model to test the efficacy of the stem cell treatment. LIGHT was shown to convey a strong antitumour effect, primarily through the induction of apoptosis. The development of techniques like this is novel and exciting, allowing a tailored and specific route of treatment for many hard to treat diseases, like gastric cancer. However, the acquisition of the UCB-MSC’s may be a restraining factor.
Lab 7 Assessment
1. a) Satellite cells effectively muscle stem cells, which can reproduce and fuse with mature muscle fibers.
b) Satellite cells are activating following various stimuli to muscle fibres. One stimuli is muscle injury such as that caused by ischemia. Initially, the muscle becomes inflamed and the dead tissue degenerates. Following this, the satellite cells at the site of injury activate and proliferate. The proliferating cells then fuse to one another to form a new myofibre, This new myofibre increases in size until it is functionally and morphologically the same as the other muscle fibres in the muscle. Satellite cells are also activated during muscle hypertrophy. As the muscle fibre grows in volume, satellite cells fuse with the cells and become myonuclei. A result of this is the ration of muscle cytoplasm to nuclei remains roughly constant no matter what the size of the individual muscle cell is.
2. Following a spinal cord injury, the affected skeletal muscle is under no stress. Consequently, it enters a period of catabolism and atrophy. This atrophy occurs at the same rate in all muscle fibre types. 6 weeks following a spinal cord injury, muscles are 45% smaller. Interestingly however, the muscles usually convert from slower, fatigue resistant muscle types to fast, fatigable muscle types.
Lab 8 Assessment
The huge picture of the eyes at the beginning of the page is perhaps necessaries. The title of the page "vision" introduces readers to the topic pretty thoroughly and comprehensively. A poorly formatted and redundant image is just an eye sore. An explanation of the images under research history would be fantastic. At the moment it is hard for someone who does not know anything about the eye (myself) to use the images at all.
There is abundant information on the retina and optic nerve, with accompanying hand drawn diagrams, which is great.
The current research section seems underdone, seems to be more a link for me to go find the research myself. A little explanation of some of the current research would make it a more complete page.
Glossary and references well done and helpful.
Abundant information, including a nice coloured in table, which is a cool idea. Unfinished though, the images to go with it would make it great. The page seems to be segmented into sections with a large amount of text, and sections with many pictures. Try for a more even distribution, if possible. Pictures seem to be relevant, with good explanations, referencing and certificates. Helpful and interesting abnormalities and current research sections
Page is well structured. Tables and images break up the information nicely. Some of the images lack an in depth explanation of what they depict/represent when you click on them. I know for some of the images it might be hard, but i think it would make for a more thorough way of presenting the information.
Not to much a critique, but you spend a large amount of time and space on the abnormalities section. When combined with the current research section and the images, only about a third of your page is information on olfaction. An even less of it is on the actual embryology when considering the timeline of discoveries and introduction. Try and draw out the embryology section a little further, considering the context of the website and who would be visiting it.
The information that is present on this page is fantastic. However, i think the layout of the page inhibits your ability to access that information a little bit. Large sections of information go unbroken by images/tables/diagrams. This strains the eyes a little bit, making it a bit of a chore to read the page. Try and include a few more images, even if they are basic. In other areas however, the images included break up the page too much, creating large white areas, detracting from the pages presentation.
There also seems to be disunity in how the different sections are formatted in regards to paragraph headings and lists. This may just be a product of teamwork and assigning different people different sections to do.
However, one important thing is that I cannot fault you for the information. It seems to be in depth, up to date, and with well structured referencing. The images you have included are well explained and referenced as well.
Overall, quite good :)
The image of the dog at the top of the page, while amusing, is not helpful nor appropriate for the academic nature of this website. The rest of the page however, is quite good. The information is extensive, very extensive. What i particularly like is that you have included a large amount of information on the actual development of the sense. It is easy with this assignment to talk at length amount the gross anatomy/physiology of the sense, without really dealing with the embryology of it.
As with most of the other projects, there are some sections that would benefit from a diagram or image. I know this is hard, especially for a paragraph dedicated to "mutation of gjb2 gene", but the large bloc of text is really quite trying for the reader. I found myself losing interest quite quickly.
Reference list is well pull together with a large body of research giving weight to your summary/ideas. Another this of note is how well explained your images are. This provides valuable information in trying to understand some of the ideas presented.
This is some discontinuity between the sections regarding how your present and list your information. This is probably just a by product of teamwork that can be ironed out easily.
Lab 9 Assessment
1.Earlier this year Carrasco et al published an intriguing article investigating the “transcriptional network hierarchy” responsible for coordinating the organogenesis of the pancreas . They studied the effects of GATA6 and GATA 4, both zinc finger transcription factors involved in the differentiation of mesodermal and endodermal cells. The reason they chose these genes was that neonates who had mutations in them commonly possessed a poorly or completely undeveloped pancreas, exhibiting high blood glucose levels and died shortly thereafter. The researchers inactivated the genes in mice, either one at a time or both. Redundancy in the genome was observed, as it required both the transcription factors to be inactivated before the effects on the pancreas were observed. Once inactivated though, the pancreatic epithelium failed to proliferate and expand, highlighting the large role GATA6 and GATA4 transcription factors play in the organogenesis of the pancreas.
1. Carrasco, M., et al., GATA4 and GATA6 control mouse pancreas organogenesis. J Clin Invest, 2012. 122(10): p. 3504-15.
2. The contributing layers are the ectoderm, mesenchyme and neural crest cells. The only contribution he ectoderm makes however, is the enamel. Thickenings of the oral epithelium, dubbed dental laminae, develop in the sixth week of embryonic development. These laminae are then populated by mesenchyme, which provides the internal part of the tooth and also the dental sac. More specifically, the mesenchyme contributes the dental papilla and later on the odontoblasts. The dental sac contributes to the connective tissue and vascular elements that link the tooth to the alveolar bone.
Lab 11 Assessment
October 2012 saw the publication of an interesting article by Nsair et al entitled ‘ Characterization and therapeutic potential of induced pluripotent stem cell-derived cardiovascular progenitor cells ’. The research in the paper concerns the use of induced pluripotent stem cells (iPSCs) in the treatment of cardiovascular disease. This is important as currently, there is very limited treatment for damaged myocardium and the fact that adult myocytes cannot divide. iPSCs are also exciting as historically it has been hard to use adult stem cells therapeutically for a long lasting benefit. Nsair et al put forward that using IPS cells that have differentiated sufficiently to commit themselves to a myocyte lineage before injection, by act as an autologous transplant and grow into the damaged tissue. By differentiating, it is hoped that some of the oncogenic risks of iPSC’s will be sidestepped.
The primary concern of the paper however is to develop a way to isolate cardiovascular progenitor cells (CPC) from the pool of iPSCs. CPCs are known to express Nkx2.5 and Isl1, with Isl1 being particularly important in the generation of the second heart field which will give rise to the right ventricle, atria and the outflow tracts. The team identified further CPC markers, Flt1 and Flt4. The cells expressing all these markers where grown feeder free in culture with the help of a beta-catenin inhibitor and some other modulatory molecules. Once grown and transplanted, the team showed that the cells differentiated into cardiomyocytes and grow. The finding of Flt1 and Flt4 as definitive surface markers for CPCs is extremely important, allowing purification of a pool of stem cells that can be used therapeutically.