User:Z3330539

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Lab Attendance

Lab 1--Z3330539 11:49, 25 July 2012 (EST)

Lab 2 Z3330539 10:52, 1 August 2012 (EST)

Lab 3 --Z3330539 10:04, 8 August 2012 (EST)--

Lab 4 --Z3330539 09:59, 15 August 2012 (EST)--

Lab 5 --Z3330539 10:10, 22 August 2012 (EST)--

Lab 6 --Z3330539 10:08, 29 August 2012 (EST)--

Lab 7 --Z3330539 10:14, 12 September 2012 (EST)--

Lab 8 --Z3330539 10:03, 19 September 2012 (EST)--

Lab 9 --Z3330539 10:08, 26 September 2012 (EST)--

Lab 10 --Z3330539 10:07, 3 October 2012 (EST)--

Lab 11 --Z3330539 10:10, 10 October 2012 (EST)--

Lab 12 --Z3330539 10:03, 17 October 2012 (EST)--

Lab 1 Assessment

--Mark Hill 18:04, 10 September 2012 (EST) Please do not include spaces before your sub-headings as this will affect formatting. I have corrected Lab 1, please correct other subheadings yourself before final assessment.

Task 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 Fertilization (IVF) technology is the combining/fusion of the males sperm and females egg/s outside the body, then later implanting this fertilized oocyte into the female uterus. This technique involves the regulation of the female cycle and monitoring of ovulation. This in vitro technique/concept has been present and studied for many years, with earliest recordings of such scientific research/findings; such test tube babies; occurring as early as 1950’s. The scientist who won the Nobel Prize in 2010, for his efforts and involvement in the discovery implementation of IVF techniques was the physiologist Robert Edwards. This was an honor given in the current medicine. Edwards with a fellow associate were the first recorded successful pregnancy and birth of the first and second IVF babies to be delivered in the late 1970’s and the 1980’s. Following this successful implantation, development and implantation other countries including Australia began to use this technique, for situations and individuals with fertility problems. Recent developments in this field of medicine and physiology have been on hormones involved in oocyte maturation, ovarian cycles such as follicle stimulating hormone, as well as the way in which sperm is administered in order for fertilization to occur.

Links: [1] [2]

Task 2

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

- “Molecular Origin of Female Meiotic Aneuploidies”

This article addresses the molecular and physiological mechanisms underlying the abnormalities in pregnancy which occur as a result of aneuploidy. It discusses the disruption of the cohesion and separation of the homologues at the centromeres and the polar ends of the spindle, which can result in miscarriage and loss of pregnancy. Lack of separation of these homologues prevents the production of two separate daughter chromatids. These errors can occur either toward the end of meiosis one and also in meiosis two, and in some instances meiosis two errors can arise as a result of meiosis one errors that were not resolved. In this article, there is particular emphasis placed upon the process of female meiosis, as the major causes of errors that can lead to aneuploidy. Major errors which occur are reduced cohesion prior to separation in meiosis two, errors in trisomies, as well as premature segregation, resulting in errors of chromatid pairing and oocyte development in fertilization. Studies are being performed to examine the role, or lack of role which certain proteins play at these stages of female fertilization in order to reduce these abnormalities in conventional and IVF development, in particular in females who fall pregnant at later maternal ages. Examining the molecular mechanisms that occur when there is loss of expression of key proteins such as SMC1 alpha and beta, Scc1 and ReC8, which leads to decrease in cohesin and reduce achiasmate, ultimately leading to lack of separation of the homologues.

[3]

NB: Originally uploaded this into the discussion/my talk page, the night before, prior to moving it into my Page (z3330539).

--Mark Hill 18:04, 10 September 2012 (EST) Answers to the 2 questions are correct. I am concerned that the text in answer to question 1 appears to be from a source that has not been cited, could you please clarify this for me (for an extra mark). You have failed to transfer the citation links correctly from your discussion page to here, and the citation links located there are not correctly formatted. You have used UNSW Library links rather than the PubMed citation number or reference format as shown in the class (and below). 7/10

As a reference number link - PMID 22841925

As a formatted reference - <pubmed>22841925</pubmed>

Lab 2 Assessment

Task 1

Immunofluorescent FN1 and integrin on blastocytes.gif


Task2

A protein which is involved in the implantation process is Rac1, which is the RAS pathway related C3 botulinum toxin substrate 1. This protein expression allows for embryonic trophoblasts to invade the stromal cell layer and when activated also allows for migration and motility of the cells of the stromal layer. All of these factors lead to the promotion of implantation.

[1]

--Mark Hill 18:22, 10 September 2012 (EST) Question 1 is not correctly linked to the appropriate reference, a serious error. Therefore you have not completed the assessment correctly, I will need to delete the image if you cannot fix the referencing and alter your mark accordingly. Image is also too small to be useful and in GIF format. Question 2 is fine, please see my previous assessment comment on referencing. 6/10


As a reference number link - PMID 18838676

As a formatted reference - <pubmed>18838676</pubmed>

Lab 3 Assessment

Task 1

Gestational age refers to the period of time, generally 14 days before the last day of the females menstrual cycle. Where as post fertilization age is the period from the point of conception/ fertilization of egg by the sperm; this mainly occurs in the middle of the menstrual cycle duration.

Gestational age is used as a clinical method of human development due to the fact that time/point of fertilization can be unknown or variable, women may have sporadic menses and ovulation, females may not be able to recall the last day of their menstrual cycle. The use of gestational age may be an approximation/generalization, however, it is more useful in reducing the variables that can occur, which are mentioned above, as last day of menstrual cycle is predominately able to be recalled by the female, and 14 days are added in order to establish room for possible variations.

References:

1. [2]

Task 2

Somites, which are present in pairs, are derived from the paraxial mesoderm and are involved in week 4 of embryonic development. Somites progressively differentiate into sclerotome, dermatome and myotome.

Sclerotome are the central cells of the somites are are located ventromedially in relation to orientation of the notochord. Sclerotome form vertebral and bone and connective of the vertebral column and are have chondrocytes present.

Dermatome are located dorsolaterally to the notochord and involved in the differentiation into dermis and epidermis.

Finally myotome are located more dorsomedially and are involved in differentiation to skeletal muscle. This involves myoblast cells. Depending on the type, these can either lie dorsomedially and then migrate to form epaxial or hypaxial muscle groups in development.

References:

1. [3] 2. [4]

--Mark Hill 18:30, 10 September 2012 (EST) Question 1 answer is correct, but your text is confusing in relation to LMP. Question 2 describes the correct somite components, and bone, CT and skeletal muscle. But you have incorrectly identified epidermis as mesoderm in origin, this is ectodermal and not from the somite. 9/10

Lab 4 Assessment

Task 1

The placenta within the developing fetus performs many functions, via maternal-embryonic nutrient transfer and later embryo-fetal nutrient transfer. Early in development diagnostic tests are able to be performed in order to examine if there are any abnormalities, either genetic or hematological, for example, within the growing embryo. These test and consecutive results are able to be obtained through the placenta. Some techniques are non-invasive, while others can be invasive for the mother. Two test which are performed through placenta diagnostics are a chorion biopsy (chorion villus sampling) and umbilical cord blood sampling. These two prenatal tests are both invasive and involve extraction of tissue and blood samples via injection of a thin needle into either the maternal cervix or abdominal wall in order to reach the uterus and retrieve samples from the placenta or the umbilical cord (the end which lies close to the placenta or the umbilical vein). Once samples are collected they are them examined within laboratories and analyzed for developmental abnormalities.

Though there is partial risk of miscarriage, these tests have been found to be successful in diagnosis of abnormalities such as down syndrome and pathological blood disorders such as Rh disease. The defects in early cell division in the embryo, with specific reference to down syndrome (trisomy 21) can be detected, as well as the compatibility between maternal and embryonic blood in relation to Rh disease. This gives the ability to detect whether there will be a maternal immune response, as a result of lack of blood compatibility (i.e. maternal immune response triggered post birth of first delivered child).

References:

1. [5] 2. [6] 3. [7]

Task 2

An article which discusses the possibilities for cord stems cells to be used in therapeutically is Human umbilical cord mesenchymal stem cells and the treatment of spinal cord injury. This review article discusses the potential for umbilical cord stems cells to be used in the therapeutic treatment of spinal chord injury or disease.

Through analysis of resent findings, researchers have discovered the similar characteristic within cord stem cells that are found in bone marrow. Cord stem cells have been found to be an alternative source for mesenchymal stems cells, and therefore are seen as a promising alternative for transplantation procedures, as they are able to differentiate into numerous cells and tissues such as bone and cartilage; as well as self renewal and growth properties. Furthermore, this area of research is being considered due to the fact that there are limitations surrounding transplantation of bone marrow mesenchymal cells, such as viral contraction and cellular amount.

The spinal cord consists of a complex molecular and cellular framework, such as astrocytes, microglia cells and myelin proteins. As a result of these many constituent, when the spine is injured or diseased, treatment is difficult due to the degenerative nature/course which these problems can occur. However, through the isolation of these cord stem cells from embryonic umbilical cord, treatment may be something that soon can be highly successful with further research and clinical development. Furthermore, isolation of these umbilcal cord stems cells are more ethically supported than isolation of bone marrow mensenchymal cells.

Further research and studies are required, however, due to the fact that some attempts, methods and techniques of recent isolations have failed. Furthermore, future areas of developmental research may include longitudinal and clinical research that can further increase awareness of umbilical cord mesenchymal cell transplantation as an alternative for complex injuries, such as those to the spinal cord.

References: 1. [8] 2. [9]

--Mark Hill 16:27, 11 September 2012 (EST) Both these answers are excellent. 10/10

Lab 7 Assessment

Task 1

a) Satellite cells are mononuclear progenitor cells that are involved in postnatal development and regeneration of skeletal muscle fibres.

b) Satellite cells can remain quiescent until they are activated by extracellular stimuli. The first example where satellite cells become activated is when there is local damage or injury to the muscles. The second example of where satellite cells can be activated is when muscles undergo hypertrophy. Although satellite cells do not have to be activated in order for muscle hypertrophy, studies have shown that they can become activated. In these cases satellite cells re-enter into the cell cycle, and myoblasts/myofibers proliferate in order to repair and/or replace cells during muscle loading or when cell injury occurs. [1]

Task 2

When motor neurons sustain a long-term injury to spinal chord studies have shown that muscle fibres undergo muscular atrophy; muscles fibres cells decrease. This muscle wasting is potentially the result of inactivation of muscles due to lack of synaptic signalling from main central conducting systems, such as the motor neurons of the spinal chord. [2] Furthermore, post spinal chord injury results in a transformation of muscle fibres. Predominately these fibres consist of both type 1 (slow) and type 2 (fast) fibre patterning, however, slow twitch fibres; specifically Type IIB, become principal after motor neuron damage. This can result in lead to reduction in the amount of fat mass, therefore contribute to wasting and weight loss. [3]

'Reference List'

1. <pubmed>17213900</pubmed>

2. <pubmed>8265728</pubmed>

3. <pubmed>9044514</pubmed>

[10] [11]

Lab 8 Assessment: Peer/Group Evaluations

Vision

There is a good balance of images and text throughout the page. Prior to final assessment the page outline and formatting of image and text positioning is required. The first image at the top the page, requires correct referencing and acknowledgement that it has been uploaded as part of a student assignment. This is also required for the image titled “Eyediagramcolour1”.

Since the previous lab, held in week 9, it is positive to see that the group has altered some of the uploaded image information, with particular reference to the self-drawn/uploaded images.

The area of the page which shows that there is a “useful links” heading and an external link within the current research section, should be placed or moved into the external links section at the bottom of the page with the appropriate information that Dr. Hill has required for placing external links on a page. Also, the references within the ‘current research’ section may also be required to be apart of the reference list.

I found this page visually appealing and I liked that this group have included an image gallery section. The use of the external links were appropriate to the topic and that the extent of the glossary for now is good, however, by the final evaluation would potentially need to be larger. Finally found that the headings for each segment of the broader topic were well positioned and relevant.

Taste

The page that you have created is very extensive and was well formatted in relation to the ratio of images to text on the page. Found that the colours and use of table for the breakdown of information in relation to ‘Timeline of developmental process’ and ‘history of discoveries’ condensed the material and made it easily understandable. This made me want to keep reading.

With majority of the images that are uploaded onto the page there needs to be the correct information and referencing provided for the summary box. From where the image was sourced (ideally of reliable and scientific literature in origin), identifying that it has been uploaded for a student assignment and copyright information-permission to use uploaded image and any other information that is pertaining to the topic and why the image was used/relevant. Further, those of you within your group that have drawn an uploaded image, have to ensure that you have stated in the summary box that it was student drawn prior to final assessment/evaluation.

The glossary is able to be expanded upon and potentially ensuring that the words that are being explained/elaborated are bolded. As a reader, I would find it easier to read and distinguish if they were bolded. The reference list that has been developed appears to demonstrate that as a group you have are well read and researched, however, the citation errors will have to be addressed and resolved prior to final marking of the project. I really appreciated the layout (headings, summary and images) of the page.

Olfaction

For me this is one of the best projects of the 6 groups. It is extremely well researched, as seen through the extensive reference list. It is evident that the group has gone above and beyond, researching even more than required for the topic, or standards set by other groups, such as clinical approaches, and much information on current research.

I found that the formatting in the upper part of the page, specifically the section under the title ‘normal function’ was a bit awkward in relation to text and image positioning. It felt that it was not consistent with the flow of the rest of the page. Also the first table may require an in-filled colour or even lines (can be a light or pale colour), just so each column and the single uploaded image is more defined and linked to the correct year/individual.

The ‘Choanal Atresia’ tomography image requires acknowledgement that the image was uploaded as part of a university assessment. However, really appreciated the breakdown of where the arrows were pointing and the relevance in relation to your specific topic. Images for the tables need to be finalized and uploaded; ensuring that there is appropriate referencing, whether they are student drawn, or sourced from the literature. Found that the student drawn diagrams were really detailed and easy to understand and appreciate. Each was also relevant to the topics, which they were linked/associated to.

Abnormal Vision

It was very good to see that this interesting topic has been well researched and that there are a number of references appropriately cited in the page.

Currently, there is a lot of text that, I as a reader, felt overwhelmed when assessing. More/larger images may need to be uploaded, or the correct formatting/resizing of existing images in order to potential rectify these concerns. It is noteworthy, however, that the ratio between text and imaging improves toward the bottom end of the page. It was good to see that there was all relevant summary, referencing and uploading information for the images that were present. Keep in mind that there is an option, and we have been encouraged to upload images that have been student drawn.

The over all formatting of the page, besides being packed with written information, had a couple of spacing issues, from extreme spaces between the bullet point genes and consequent descriptions, in the ‘abnormal lens development section’, to virtually no singular spacing between the research timeline. in the ‘Genes’ section.

A way to aid to the above so that the page potentially is more visually appealing, is to place the genes and subsequent function into tables, or even placing the timeline information in a table form, or adding originality by actually placing this information on a timeline generated by one of the group members. Overall though, I found that it was a very engaging topic and page presented.

Hearing

This is a well-formatted project page. There is a great balance and positioning of image and text information throughout. The way that the information, headings and subheadings are positioned made the contents flow and engaging. I especially found the image of the dog with the big ears, and the opening line of the introduction “Can you hear me!” drew me in as a reader. Just be sure in editing prior to the final assessment date that there are no grammatical errors, such as missing question marks (?).

Some of the uploaded images, such as the ‘normal cochlear’ image in the inner ear sub-heading of the development section, require, that information is attached stating the image was uploaded as part of a university assessment. The drawn or student edited drawings were well used and uploaded, having the appropriate summary and uploading information required.

The tables were very effective in presenting the information in a concise way, and I found that the summary box for the inner ear was well put together in highlighting the key points. Images still need to be uploaded prior to the final assessment date in the tables as indicated.

Finally, external links that are in the environment section and in some of the tables rows will need to be transferred to the external links section and appropriately numbered and formatted once in this sections. The reference list is very well established, however, ensure that the template citation of reference 56 is correctly formatted before final project date.

Lab 9 Assessment

Task 1

A recent research review article, which was found in relation to development of the thyroid- endocrine organ, was The thyroid hormone responsive protein (THRP) has a critical role in the embryogenesis of Xenopus laevis. Though this article pertains to embryology of the frog, it highlights the significance THRP has in endocrine, and entire embryology through this animal model.

This article demonstrates the link between the endocrine system and neuronal embryogenesis and the effects that can occur if there are mutations or over expression of protein levels produced/controlled by the thyroid. THRP normally is controlled and responsive via the thyroid gland. It is also a reading frame for expression of proteins and genes that are involved in c-Abl signaling (such as Abi-2), which contribute significantly to neuronal development. In this article, in vivo tests were performed, whereby THRP was expressed in vectors, during development, in order to establish the effect this neurotoxin protein had upon the neuronal development in Xenopus laevis (frogs). In places where there was over expression of THRP, tadpoles demonstrated severe malformations, which correlated to similar findings in previous mouse model studies mouse models, resulting in spinal chord deformation.

This demonstrates that the thyroid plays a significant role as a control and regulating centre for the expression and release of proteins such as THRP. Without its normal development and function, embryonic, neuronal development can be negatively effected, leading to postnatal deformities of the central nervous system (CNS).

Reference

<pubmed> 2109522</pubmed>

Task 2

Teeth develop embryonically through a balance between epithelial and ecto-mesenchyme (ectoderm) of the oropharyngeal cavity. Development also involves the neural crest and the first f the pharyngeal arches. Teeth begin development at week 6 (stage 16-17) and postnatal alterations and maturations occur.

Other tissues that are involved in teeth development are odontoblasts, which originate from the neural crest. Which are involved in bud formation of the tooth in initial week 6 developments. Odontoblasts secrete predentin, which when calcified becomes a potein called dentin, which work in conjunction with enamel (secreted by specific cells called ameloblasts), to strengthen and develop teeth.

When teeth form, they progress from an initial lamina layer, then progression to placode (dental) formations, and progress morphologically through bud formation, to cap and then finally to a bell shape; developing into the gum space beneath teeth. At the sites of dental placode formation, there is growth of epithelial cells, which will secrete elements such as enamel teeth strengthening.

Finally, many odontogenic genes are present in these stages, which allow for signaling and transcription factor activation and encoding of genes related to teeth development.

Reference

<pubmed>19266065</pubmed>

Lab 11 Assessment

The recent understanding and development of Induced pluripotent stem cells (iPSC) in medical, scientific and biotechnological fields has opened up many areas of research. Scientists are now formatting their research around transcription factors, such as Sox2 and Oct4, which were initially and currently, used to formulate induced stem cells. This area of research has expanded capabilities of producing models of human disease, understanding of human physiology and potential treatments.

A current research article that has applied methods of iPSC in order to understand a pathological process is Induced Pluripotent Stem Cell Models of Progranulin-Deficient Frontotemporal Dementia Uncover Specific Reversible Neuronal Defects. Frontal and temporal dementia (frontotemporal-FTD) is unfortunately not fully understood in relation to underlying mechanisms of disease and has no current treatment. However, through observing clinical manifestations and neuronal tests, researchers have found a link between pathology of FTD and mutations occurring of the genes that affect patients neurologically.

In particular the heterozygous mutation of progranulin (PGRN S116X), has been found to be present in case of FTD. Patients with FTD demonstrated depletion in the amount of protein product produced (haploinsufficiency). In this article, patient iPSC lineages were produced in order to establish a molecular understanding of the PGRN S116X mutations and develop a model of PGRN haploinsufficency.

From this, researchers were able to recognize the various signaling pathways involved, such as MEK and PI3K. As a result defects that occurred along the pathways where also observed in cases where there was deficiency in PGRN and therefore mutation. This finding has lead to questions surrounding particular treatment options and further iPSC lineage generation for other proteins that may be affected genetically through signaling pathways and mutations.

<pubmed>23063362</pubmed>

  1. <pubmed>17213900</pubmed>
  2. <pubmed>8265728</pubmed>
  3. <pubmed>9044514</pubmed>