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Online Assessment

Lab 1 Assessment

Article 1

<pubmed>24760595</pubmed> The following case study investigated the effects of hepatitis B virus (HBV) infection on sperm parameters, ovarian stimulation, and outcomes of in vitro fertilization (IVF) and embryo transfer, as the impact of HBV on human infertility was questionable. During this study, a total of 224 couples were identified, where either one or both partners were HBsAg-seropositive, and were undergoing their first IVF and embryo transfer cycle. The morphology of their sperm was analysed, as was the quality of their embryo rate, the duration of infertility and their fertilization rates, and then compared to those of 448 HBsAg-seronegative couples. In all four cases, the results of the HBsAg-seropositive couples were inferior to those of the HBsAg-seronegative couples, expressing significantly lower normal sperm morphology, top-quality embryo rate and fertilization rates, and significantly prolonged durations of infertility. It was noted however, that in regard to clinical pregnancy rates, there was no significant difference between the two groups. Based on the case study results, it was concluded that HBV infection was likely to cause infertility.

Article 2

<pubmed>24602756</pubmed> The following case study sought to investigate whether assisted reproductive technology (ART) treatments had any impact on the sex ratio of babies born. Using the United Kingdom records of women who have conceived children between 2000 and 2010 using intrauterine insemination, IVF, or intracytoplasmic sperm injection (ICSI), the records of a total of 106,066 babies born to 76,994 mothers were analysed. The results showed that each form of ART resulted in a varied sex ratio, the most significant variation occurring from IVF with 52.1% of babies born male, and the least variation occurring from ICSI embryo transfer, with 49.3% of babies being born male. It was also found that when the embryos were transferred during the blastocyst stage in ICSI and IVF, as opposed to during the early cleavage-stage ET, it resulted in approximately 6% more males being born. It was concluded however, that due to the significantly increasing number of babies born using ART treatments, more research was needed into the causes of the gender bias after such treatments.

Lab 2 Assessment

These histological views show the morphology of the kidneys of wildtype mice (left) compared to those of transgenic line A homozygous mice (right) that have been injected with Gremlin, an embryonic gene that plays a role in nephrogenesis. These images show what can occur to the morphology of the kidney if this gene is over-expressed.

Lab 3 Assessment

The kidneys first develop in the embryo by a process called nephrogenesis, in which self-renewing mesenchymal renal stem cells produce nephrons to form a simple embryonic kidney, called the pronephros. Nephrons are the main functional unit of the kidney.

An embryonic gene named gremlin (GREM1) has been found to play a key role in the formation of the kidneys and nephrogenesis in general. When fully formed, the expression of this gene is relatively low in an adult. However, it is thought that many renal diseases and their progressions are linked to an overexpression of this gremlin gene.

Nephrogenesis is stimulated by the signaling between the epithelial ureteric buds and progenitor cells, causing nephrons to develop and the ureteric buds to branch.

At birth, although the infant’s kidneys are developed enough to maintain homeostasis and are sufficient for growth and development, their functional capabilities are decreased. This is a result of the transition from depending on the placenta to maintain homeostasis of fluid and electrolyte balance while in-utero, to maturation of the neonatal glomeruli once born.

Determining nephron number is important: it can show the success/extent of nephrogenesis, and thus be used to determine if any and what genes and environmental factors may aid this process; a low nephron count has been linked to multiple cardiovascular and renal disease later in life.

The overexpression of the gremlin gene (GREM1) has been found to be a cause of renal disease.

Lab 4 Assessment

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

<pubmed>25130827</pubmed> A study was conducted to determine whether the combination of umbilical cord mesenchymal stem cells (UC-MSC) with haploidentical hematopoietic stem cells (haplo-HSCT) would produce a more effective outcome and positive result when transplanted into patients suffering from refractory/relapsed myeloid leukemia. Using results obtained from January 2007 to June 2013, the data of 36 patients who received such treatments were analysed with respect to the engraftment (the rate at which the stem cells are able to reproduce new cells), graft versus host disease ((GVHD) a condition in which the donor stem cells attack the recipient’s body), and their two-year overall survival.

After reviewing and analysing the results, it was determined that the average engraftment time of neutrophils was 12 days, while the average time for platelets was 14 days. The cell counts of both, however, were well below that of the normal range of a healthy individual. In terms of GVHD, 5 of the 36 patients suffered grade III to IV acute GVHD, 12 of 32 suffered chronic GVHD, 2 patients had extensive chronic GVHD, and 3 patients relapsed. Despite this, the two-year OS rate was calculated to be 76.9%, with the final assessment concluding that the combination transplantation of stem cells was a good therapeutic method, especially as an alternative to patients with high risk or unsuitable donors.

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

<pubmed>3052747</pubmed> There are three developmental vascular ‘shunts’ present during embryo and fetal development:

• Ductus arteriosus – it connects the pulmonary artery with the descending portion of the aortic arch, and works to ‘shunt’ the majority of the output from the right ventricle away from the undeveloped lungs.

• Ductus venosus – it connects the portal sinus to the inferior vena cava, allowing oxygenated blood received from the umbilical vein to rapidly enter the central circulation by diverting around the liver.

• Foramen ovale – it connects the right atrium to the left atrium, allowing oxygenated blood from the former to enter the latter.

Lab Attendance

Lab 1 --Z3465654 (talk) 12:45, 6 August 2014 (EST)

Lab 2 --Z3465654 (talk) 11:18, 13 August 2014 (EST)

Lab 3 --Z3465654 (talk) 11:16, 20 August 2014 (EST)

Lab 4 --Z3465654 (talk) 11:06, 27 August 2014 (EST)

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