User:Z3332885

From Embryology

Lab Attendence

Lab 2 --Z3332885 10:38, 1 August 2012 (EST) Lab 3 --Z3332885 11:05, 8 August 2012 (EST) Lab 4 --Z3332885 12:10, 15 August 2012 (EST) Lab 5 --Z3332885 11:58, 22 August 2012 (EST) Lab 6 --Z3332885 10:13, 29 August 2012 (EST) Lab 7--Z3332885 11:36, 12 September 2012 (EST) Lab 8 --Z3332885 11:26, 19 September 2012 (EST) Lab 9 --Z3332885 10:11, 26 September 2012 (EST) Lab 10 --Z3332885 10:36, 3 October 2012 (EST) Lab 12 --Z3332885 10:39, 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

Research into controlling fertility has been going on for a while, and many experiments for IVF has been conducted since the 1960s. In 1973 the first IVF pregnancy was achieved, though baby did not survive till birth. In the 1978 the first IVF baby was born in india. The baby named "Durga" was the work of physican Kolkata using primitive methods and household refrigeration. In 1979 the world’s second baby conceived by IV was born.


In 2010, the Nobel Prize for physiology medicine was awarded to Robert G. Edwards for his contribution in the development of In Vitro Fertilization. [1]


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

Summary

Many embryos are discarded from IVF labratories because they are considered to be poor quality. These embryos are, however, proposed to be good sources for human embryonic stem cells (heSC). This article studied whether heSC could be isolated from poor quality embryos, while also evaluating the efficiency of different isolation methods. Their experiments involved 166 embryos. The embryos were culture in a blastocyst medium for 2 days so that inner cell masses could develope. The inner masses from 32 embryo cells were then isolated, 17 using a mechanical method, the other 15 by immunosurgery. The isolated ICMs were subcultivated, and the rates of ICM colony formation was measured. Both methods had similar success rate (P>0.05). However, the cultures that did work had normal hESC differentiation ability, which indicates heSC could be derived from poor embryos. [2]

References

   1.http://en.wikipedia.org/wiki/In_vitro_fertilisation
   2.Liu W, Yin Y, Long X, Luo Y, Jiang Y, Zhang W, Du H, Li S, Zheng Y, Li Q, Chen X, Liao B, Xiao G, Wang W, Sun X.
     Derivation and characterization of human embryonic stem cell lines from poor quality embryos. J Genet Genomics. 2009 PMID: 19376483 

Lab 2 Assessment

Question 1. Upload an image from a journal source relating to fertilization or the first 2 weeks of development as demonstrated in the practical class.

Egradation of Intact Oocyte Zonae by Isolated Sperm Proteasomes.jpg


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

L-selectin is an adhesion molecule belonging to the selectin family of proteins. In the implantation process, L-selectin on the uterine epithelial cells interacts with sLex molecule on the trophoblast to mediate adhesion. This interaction has also been shown to induce the subsequent apoptosis of the uterine epithelial cells. 1


References

1. Liu S, Yang X, Liu Y, Wang X, Yan Q. sLeX/L-selectin mediates adhesion in vitro implantation model. Mol Cell Biochem. 2011 Apr;350(1-2):185-92. PMID: 21197561

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- time between the last menstrual period and birth (measured in weeks). Post-fertilizational age- time elasped from fertilization to birth.

Clinically, the gestational age is used to describe human development. Gestational age can easily be determined by working out the number of weeks since last menstrual period, whereas the post-fertilization age is hard often hard to determine. Knowing this number can help determine the morbidity and mortality of the baby. 1


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


Sclerotome- Vertebrae and ribs 2

Dermatome- The dermis of the dorsal skin 3

Myotome- Skeletal muscles of the back 4


References:

1. http://www.nlm.nih.gov/medlineplus/ency/article/002367.htm

2. http://en.wikipedia.org/wiki/Sclerotome

3. http://en.wikipedia.org/wiki/Dermatomal_mesenchyme

4. http://en.wikipedia.org/wiki/Myotome

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.

Amniocentesis - amniotic fluid containing fetal tissue is sampled from the amnion using a needle. The DNA from the sample is then tested for genetic abnormalities such as Down syndrome (trisomy 21) or Patau syndrome (trisomy 13). 1

Chorionic Villus Sampling - chorionic villus (placental tissue) is sampled and tested for chromosomal abnormalities. This procedure usually takes place at 10–12 weeks' gestation. Down syndrome and Tay-Sachs disease can be detected using this technique. 2


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

This study was conducted to better understand hematopoictic and endothlial precursor cells from umbilical cord blood, and their possible use as cell-based therapies for ischemic diseases.

Results

On a growth factor depleted matrigel, ALDH(hi) cells significantly increased tube formation in Human umbilical vein endothelial cells. Transplantation of ALDH(hi) cell was also observed to significantly improve the recovery of perfusion in an ischemic limb (femoral artery ligation), corelation with an increase in murine vWF(+) blood vessel and CD31(+) capillary densities. UCB ALDH(hi) cells promote vascular regeneration and can therefore be use used to develope therapeutic strategies in treating ischemic diseases.

Reference

1. http://en.wikipedia.org/wiki/Amniocentesis

2. http://en.wikipedia.org/wiki/Chorionic_villus_sampling

3. Putman DM, Liu KY, Broughton HC, Bell GI, Hess DA. Umbilical Cord Blood-Derived Aldehyde Dehydrogenase-Expressing Progenitor Cells Promote Recovery from Acute Ischemic Injury. Stem Cells:2012,16(8)PMID: 22899443

Lab 7 Assessment

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

Myosatellite cells are mononuclear progenitor cells, found between the sarcolemma and the basement membrane of terminally differentiated muscle cells. These cells represent a population of stem cells, which are quiescent normally, but can proliferate to regenerate muscles in response to injury. Two examples of statellite cells being activated are:

Mechanical stress- strenuous exercise produce tears in the myofibers

Chronic diseases- causing hypertrophy of muscle cells.

When activated, the satellite cells enter the cell cyle to produce myoblasts that fuse/replace the damage cells.


2.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?

When the innervating motor nerve of skeletal muscle is damage, the muscle fiber will no longer be receiving nerve impulses to contract, leading to paralysis. The inactivity of the muscle in the long term will also cause atrophy. This is marked by the loss of type I (slow) fibres and the muscle become predominantly composed of fast glycolytic type II fibres.


References

1. <pubmed>17213900</pubmed>

2. <pubmed>16931550</pubmed>

Lab 8 Assessment

Vision

Overall the information presented is clear and concise. The development section is well researched and provides information of each individual part of the eye. The introduction is very brief and needs more on the development of the eye (as the project is on the development part. I feel that the anatomy should be under a separate heading. It also has two images that the serve essentially the same purpose. The historical section needs more on recent discoveries not just ancient ones. More work needs to be done on the layout of the images as is often hard to determine which image relates to which text. For the current research section, I think the group would benefit if they give a summary of the research as opposed to just listing the articles.


Taste

The introduction is very detailed, with descriptions of the varies components of taste. Although informative, there needs to be more about the development of the different aspects of taste. I feel that the type 2 receptor part doesn't belong here as this section is here to introduce the topic (maybe put it in a separate heading or in the neural pathway section?). There also needs to be a diagram if you are to include this as if is hard to follow. The balance between text and images is good, though some of the images are not labelled or properly referenced. Histories of discoveries section is very detailed and the table was very easy to read. The section the development of the taste is very informative and shows a of effort is placed into the of research of the topic (as it is often hard when the topic is not well understood). The section on the Structure and Function of the adult tongue gives the anatomy of the tongue, and should come before the part on neural pathways. The current research provided descriptions of the research and their goal and is done well.


Olfactory

The introduction, though brief, captured my attention and made me want to read more. It did exactly what is was supposed to do; provide an introduction to the topic, while keeping it interesting. Both the history and the development timeline sections are well researched and referenced. For the timeline part, there are large chunks of text describing processes but with no images to support them. This makes it confusing and hard to follow (especially when describing the development process). The division of the abnormalities and the inclusion of the pathophysiology is very thorough and is done very well. This part was very interesting to read. Current research is also well structured, and more importantly, relates to the abnormalities describe above. Overall this group has done an exceptional job.


Abnormal Vision

Your introduction is short, but did state what you will be duscussing and the purpose of the webpage. However I think it would help by having more on what the abormalites are and how they affect people suffering from it. The section on normal eye development had sufficient information, though a few images would help. The section on Abnormal Development and and the choice of subsection is very well thought out and presented. The texts were easy to read and very detailed. More importantly, they were backed up current research which shows information is up to date. However, be careful not to have too much on the molecular pathways as can be hard to understand (may be break them up a bit and relate them to the concept discussed). More attention needs to be paid the formatting of the text and the placement of the images but otherwise, great job.


Hearing

The introduction is concise and straight to the point. It gave an overview of the webpage and clearly indentified the purpose. The use of humor is welcoming though I think that image of the dog is over the top. Due to the great choice of subheadings, the development part is very easy to follow. More images to accompany the text would make it easier to understand would help break up some of the text. The current research section feels lacking. Referencing need to improve as some paragraphs have none.

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.

In mice, Gata4 and Gata6 genes are linked to to pancreas developement, and their elimination cause pancrease agenesis. The simutaneous deletion of both these genes disrupts the prolifereation of pancreatic progenitor cells, and cause defects in the branching morphogenesis. Interestingly, it was found that the loss of only one these genes leads to mild pancreatic defects, and these defects are often resolved postnatally.

Reference: <pubmed>23006325</pubmed>


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


Layers and tissue that contribute to the developing teeth are:


Ectoderm: form Ameloblasts that deposit proteins which later mineralize to form the enamel.


The neural crest: Majority of the dental papilla of the tooth arise of the neural crest. Cells include odontoblasts, osteoblasts, and cementoblast.


Mesoderm: Dental papilla cells that from blood vessels in the pulp of the tooth.


Reference: "Development of the teeth." n.pag. embryology.ch. Web. 2 Oct 2012. <http://www.embryology.ch/anglais/sdigestive/gesicht05.html>. [1]


Lab 10 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.



This article looks at the use of Liposomal Magnetofection (LMF) as a method of producing induced pluripotent stem (IPS) cells. IPS cells are traditionally made using viral vectors systems, which as a result pos


Overall, it was found that LMF effective and reproducible method of generating virus free iPS cells.

[PUBMED23049868]

  1. "Development of the teeth." n.pag. embryology.ch. Web. 2 Oct 2012. <http://www.embryology.ch/anglais/sdigestive/gesicht05.html>.