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•Ductus Venosus: a temporary blood vessel that originates from the umbilical vein this bypasses the fetal liver and goes directly to      the fetal heart.
•Ductus Venosus: a temporary blood vessel that originates from the umbilical vein this bypasses the fetal liver and goes directly to      the fetal heart.
===Lab 5===
'''Oesophagus Stenosis'''
Oesophageal stenosis is the narrowing of the oesophagus which usually occurs in the distal third. The oesophagus needs recanlization at the end of the embryonic phase to be complete. Oesophagus stenosis is when this recanalization is incomplete hence creating a significantly narrow lumen. This occurs during the eight week of human embryologic development. Oesophageal stenosis may also occur due to lack of blood supply to the affected area or the lack of development of the blood supply to the affected area. Usually the oesophagus lengthens but when the mishap of recanalization happens, it results in shortened oesophagus which then leads to the stomach being displaced superiorly through the oesophageal hiatus. 
''References:''
<pubmed>22470735</pubmed>
{{cite web |url=http://www.nature.com/gimo/contents/pt1/full/gimo6.html |title=Esophagus - anatomy and development |last1=Braden Kuo |first1=M.D. |last2=Daniela Urma |first2=M.D. |date=16 May 2006 |website=Goyal & Shaker GI Motility Online }}

Revision as of 01:54, 6 September 2014

Lab Attendance

Lab 1 --Z3414515 (talk) 12:46, 6 August 2014 (EST)

Lab 2 --Z3414515 (talk) 11:14, 13 August 2014 (EST)

Lab 3 --Z3414515 (talk) 11:07, 20 August 2014 (EST)

Lab 4 --Z3414515 (talk) 11:14, 27 August 2014 (EST)

Lab 5 --Z3414515 (talk) 11:13, 3 September 2014 (EST)

Practice

http://www.ncbi.nlm.nih.gov/pubmed

PubMed

Pmid4118885

<pubmed>4118885</pubmed>

My Type in a Group

Teamworker

A Teamworker is the oil between the cogs that keeps the machine that is the team running smoothly. They are good listeners and diplomats, talented at smoothing over conflicts and helping parties understand one other without becoming confrontational. Since the role can be a low-profile one, the beneficial effect of a Teamworker can go unnoticed and unappreciated until they are absent, when the team begins to argue, and small but important things cease to happen. Because of an unwillingness to take sides, a Teamworker may not be able to take decisive action when it is needed.

Lecture Reviews

Lecture 1

Course introduction for embryology as well as the history of embryologists and how the diagrams of embryo changed through time as more advance technology was available. Guidelines to the course was mentioned as well as the assessments and type of work expected for this course.

Lecture 2

In the fertilization lecture the most interesting concept for me was the polar bodies and the sry gene. Every other concepts such as gametes, mitosis, meiosis and fertilization was familiar. Polar bodies and the sry gene was a completely new idea for me. Meiosis 1 releases first polar body and meiosis 2 releases the second polar body. Sometimes meiosis 1 releases first and third polar bodies.

Individual Assessments

Lab 1

Reference: Pmid25089626

<pubmed>25089626</pubmed>

Method summary

Microarray Analysis

Raw data on Affymetrix GeneChip HGU133 were obtained from the ArrayExpress for human preimplantation embryos. The invariant set normalisation method was used and via using the Li-Wong method, the expression values were extracted from PM-values. The arrays were normalised independently and Li-Wong method was applied to all normalised arrays to get a summary of the expression measurements. Using Bayesian approach, differential expression between the consecutive development stages was analysed.

Embryo Collection

FVB/N mice were kept for 12 hours under light/dark cycle and were fed regularly. A Pregnant Mare’s Serum (5 IU) was injected into a 4-7 weeks old female. After 44 hours a human chorionic gonadotropin (5 IU) injection was given. The females then mated with the FVB/N strain studs (males). 19-21 hours later the females were sacrificed and the oviducts were collected. Oocytes were collected. The embryos were then cultured in KSOM medium.

Gene expression analysis

Extraction of RNA from mouse unfertilised oocytes using Arcturus PicoPure RNA isolation kit was done. Agilent Bioanalyser was used to measure the RNA quality and concentration. One embryo yielded 128 pg of total RNA on average. For each final protocol, three biological replicas of all the stages were collected.

TaqMan Array Cards analysis

RQ Manager version 1.2.2 (Applied Biosystems) were used to analyse Ct values. Hprt1 and Psmb6 were the endogenous controls which were used for normalisation.

Expression analysis from public sequencing dataset

Gene Expression Omnibus database was used to obtain the normalised RPKM values for human and mouse pre-implantation stages. The p-values were calculated for the pairs i.e. oocytes and 4-cell blastomeres and etc. The p-values below 0.05 were significant. In human and mouse, the average values for each stage between embryos in the same biological stages were calculated.

Result summary

Analysis of two independent human pre-implantation microarray datasets were done in order to define the genes with consistent gene expression profiles between embryo stages. The probes which had significant changes in both datasets were considered for further analysis. Probes in the “Up-down” cluster were up regulated whereas the probes in “Down” cluster were down regulated. Genes were selected from each cluster “Up”, Up-down” and “Down” for analysis of expression profile of mouse pre-implantation embryo by qPCR. A gene was included if its ortholog was found in any of the following samples in MGI: oocyte, unfertilized oocyte, fertilized oocyte, 2-cell embryo, 4-cell embryo, 8-cell embryo, 16-cell embryo, blastocyst. In the mouse, 55 genes with orthologs were selected for gene expression profiling. Also expression patterns of the selected genes in the mouse were studied. The maternal gene expression profile was seen to be shared in more than half of the mouse orthologs for genes “Up” and “Up-down” clusters. All the PRAME and most SSX, MAGEA and GAGE family members in human microarray were of “up-down” cluster. However, in the pre-implantation human embryo, the selected families’ genes had dynamic expression profiles.

Reference: Pmid25071849

<pubmed>25071849</pubmed>

Method summary

This study was performed in Assisted Reproduction of Wuhan Union Hospital from January 2012 to December 2012. A total of 1891 cycles were used which contained 1150 fresh embryo transfers and 741 frozen-thawed embryo transfers. Cleavage-stage or blastocyst-stage was composed in 1150 women. Also 741 women were divided into cleavage-stage or cleavage-stage extended blastocyst culture or blastocyst-stage transfer. A GnRH agonist protocol was used in all the cycles. An injection of 10000 units of HCG was given to two or more follicles when they reached 18mm in diameter and then 34-36 hours later an ovum pick up was performed. After OPU, 4-6 hours later in vitro fertilisation was performed. The assessment for the embryo was based on the rate of development and morphology. All the good embryos were cryopreserved through vitrification. The number of implantations was observed as the number of sacs. Using the SPSS software, all the statistical calculations were performed.

Result summary

Clinical pregnancy rates for patients less than 35 years of age:

  • Fresh cleavage-stage embryo transfers: 52.7%
  • Fresh blastocyst transfers: 35.88%
  • Frozen-thawed cleavage-stage embryo transfers: 35.29%
  • Post thaw cleavage-stage extended blastocyst culture transfers: 47.75%
  • Frozen-thawed blastocyst transfers: 59.8%

Clinical pregnancy rates for patients more than 35 years of age:

  • Fresh cleavage-stage embryo transfers: 41.24%
  • Fresh blastocyst transfers: 26.92%
  • Frozen-thawed cleavage-stage embryo transfers: 11.32%
  • Post thaw cleavage-stage extended blastocyst culture transfers: 46.15%
  • Frozen-thawed blastocyst transfers: 55.8%

Lab 2

E18.5 developing kidney expressing Pygo1 and Pygo2.jpg


E18.5 developing kidney expressing Pygo1 and Pygo2

Expression patterns of Pygo1 and Pygo2 proteins in the cortex of E18.5 kidney was determined using immunofluorescence. The location of both Pygo1 and Pygo2 were in the nucleus with the colour red. Both genes are expressed widely where in all the components of the developing kidney, a signal is detected. However their were high levels of stromal cell compartment(arrows). Original magnification x200


--Mark Hill (talk) 16:14, 21 August 2014 (EST) The correct information was associated with the image summary box, you do not need to repeat copyright and student template here. Images when used in your project will though include a reference link.

Reference

<pubmed>17425782</pubmed>

© 2007 Schwab et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Note - This image was originally uploaded as part of an undergraduate science student project and may contain inaccuracies in either description or acknowledgements. Students have been advised in writing concerning the reuse of content and may accidentally have misunderstood the original terms of use. If image reuse on this non-commercial educational site infringes your existing copyright, please contact the site editor for immediate removal.

Lab 3

These are only the tip of the ice burg journal articles but further details will be mentioned later throughout this course as my path comes closer to its destination.

<pubmed>23799566</pubmed>

<pubmed>22750256</pubmed>

<pubmed>23720330</pubmed>

Lab 4

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

Therapeutic effect of human umbilical cord-derived mesenchymal stem cells in rat severe acute pancreatitis.

A technique used called flow cytometry illustrated that expressions of CD45, CD34, CD11b, CD19 and HLA-DR were lacking in MSCs derived from umbilical cord. However high expressions of CD44, CD73, CD90 and CD105 were observed. MSCs have the capability of osteogenesis, adipogenesis and chondrogenesis which was observed from the experiment of induction differentiation.

In control group, there were no edema, bleeding, inflammatory cells and necrosis in the pancreatic lobules at different times. Pancreatic edema was immediately observed after surgery in SAP group. Expansion of alveolar system, infiltration of inflammatory cells and parenchymal bleeding was noticed one day after surgery. Pancreatic parenchymal necrosis weakened three days after the surgery. The merging of necrotic area was seen five days after the surgery followed by the observation of tubular complexes. In SAP+MSCs group, over time the pathological changes improved and small amount of fibrous tissue were observed. Pathological scores for SAP were higher than those of the control group with regards to pancreatic parenchymal bleeding and nercrosis, pancreatic edema and infiltration of inflammatory cells.

After MSCs transplantation, apoptosis of pancreatic acinar cells reduced. In SAP group, large numbers of apoptosis cells in pancreas were noted. After MSCs transplantation, the apoptosis cells reduced in numbers since day 3. In SAP+MSCs group the number of apoptosis cells were lower than those in the SAP group on days 3 and 5.

Reference:

<pubmed>24294357</pubmed>

2. There are a number of developmental vascular "shunts" present in the embryo, that are closed postnatally. Identify these shunts and their anatomical location.

There are three vascular “shunts” present in the embryo. These are:

•Foramen Ovale: an opening that allows blood to flow from right atrium to the left atrium. This opening is located in the interatrial septum. There is a valve that is associated with this opening during the fetal period to prevent back flow of blood. This shunt closes when the blood pressure in the atria increases due to the newborn beginning to breathe.

•Ductus Arteriosus: is a short, muscular vessel which connects the pulmonary trunk and the aorta. Majority of the blood pumping into the pulmonary trunk from the right ventricle is therefore diverted into the aorta. Thus only enough blood reaches the fetal lungs to maintain the developing lung tissue. The pressure within the lungs drops dramatically as the newborn takes the first breath thus expanding both the lungs and pulmonary vessels. The smooth muscles in the wall of the ductus arteriosus constrict as the amount of oxygen increases hence sealing off the passage.

•Ductus Venosus: a temporary blood vessel that originates from the umbilical vein this bypasses the fetal liver and goes directly to the fetal heart.

Lab 5

Oesophagus Stenosis

Oesophageal stenosis is the narrowing of the oesophagus which usually occurs in the distal third. The oesophagus needs recanlization at the end of the embryonic phase to be complete. Oesophagus stenosis is when this recanalization is incomplete hence creating a significantly narrow lumen. This occurs during the eight week of human embryologic development. Oesophageal stenosis may also occur due to lack of blood supply to the affected area or the lack of development of the blood supply to the affected area. Usually the oesophagus lengthens but when the mishap of recanalization happens, it results in shortened oesophagus which then leads to the stomach being displaced superiorly through the oesophageal hiatus.

References:

<pubmed>22470735</pubmed>

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