Stem cell research is the future of medical and biological research and remedies, and it is fascinating to watch the progression of this new and important science as it unfolds. These cells were discovered in mouse embryos in the 1980s, and are remarkable because of their potential to grow into a variety of different kinds of cells within a body. Common in fetuses, and more rare in adult animals of all kinds, stem cells can be manipulated in useful ways to repair many tissues, dividing limitlessly for therapeutic purposes. When a stem cell divides, each new cell has the potential either to remain a stem cell or to differentiate into more specialized tissue, such as nerve, pancreas, bone marrow, or unique blood components. Initially
1. Many experiments were conducted during the 1950s and 1960s with chick embryos and they showed that two patches of tissue essentially controlled the development of the pattern of bones inside limbs. Describe at
into an early stage embryo while still in a test tube. Scientists place the early stage embryo into
A total of 11 studies were selected for this review to prove the hypothesis that repetitive SRCs lead to changes in the white matter of a developing brain. The aim of the study is to ascertain the changes in the myelination of the CNS due to concussion through DTI scans. After a thorough review, it is clear that multiple sport-related concussions in young athletes cause alteration in the white matter of the brain (Barkhoudarian et al., 2011; Bazarian et al., 2012; Cubon et al., 2011; Keightly et al., 2014; Marchi et al., 2013; Prins et al., 2010; Smits et al., 2011; Toledo et al., 2012; Wilde et al., 2011; Wozniak et al., 2007; Wu et al., 2010). This study consists of 3 systematic reviews, 6 prospective cohort studies, 1 animal model study and 1 cross-sectional study. The results are presented in the above order.
The phrase “stem cell” calls to mind images of controversy: Pro-life picketers outside abortion and in-vitro fertilization clinics, patients with chronic disabilities waiting on a cure, scientists in a lab experimenting with a petri dish. These cells offer unimaginable opportunities for regenerative medicine because they can retain the ability to differentiate. Stem cells are classified as either adult or embryonic. Embryonic stem cells can
In order to get stem cells from embryos, the embryo must be destroyed, and many people view this as killing a human, making it immoral. These embryonic cells can be given different tasks such as making a specific organ, and this is how different body parts can be made. Stem cells have been published in newspapers since 1998, but no institute or company invested money or time into stem cells until 2001, when the Canadian Institute of Health Sciences decided to fund the research of stem cells. Stem cells have three general properties, which are being capable of dividing and renewing for long periods, they have to be unspecialized, and they have to be able to give rise to specialized cells (NIH 3). Stem cells are unspecialized cells in embryos and umbilical cords that can be modified using signals in order to make specialized cells which then have the ability form into various different body parts such as livers, kidneys, hearts, and other major organs. The process of when an unspecialized stem cell turns into a specialized stem cell is called differentiation (NIH 1). In order for unspecialized stem cells to become specialized, one of the two types of signals should be used. The first signal is called internal. Internal signals occur inside a cell by its own genes, which are encoded on strands of DNA. The second signal is called external and this is possible with external support such as chemicals, physical contact, or other molecules in the
Over time, the use of human stem cells has proven to be monumental in research, particularly in the field of disease modeling and drug development for treatments of diseases. However, there are many barriers that come with using human stem cells, specifically embryonic stem cells (ESCs), mainly due to the fact that they must come from either
The goal of this paper is to compare the utility of adult, embryonic and induced pluripotent stem cells (iPSCs) to treat Parkinson’s disease. As such several things will be assessed, dosage of stemcells, improvement in motor function, in combination with the presence of α-synuclein proteins and cell survival.
Stem cells are grown on Petri dishes in a laboratory and are never implanted in a woman’s uterus. These cells can be used to create stem cell lines that can grow indefinitely under optimal conditions (“Stem cells and diseases,” 2011). Embryonic stem cells can be obtained from existing stem cell lines (any group of cells that came from the same original embryo), aborted or miscarried embryos, unused in vitro fertilized embryos, and cloned embryos created from somatic cell nuclear transfer (the nucleus from an unfertilized egg is removed and replaced with a nucleus from an adult stem cell). This technique would be used for therapeutic cloning, which could grow organs or skin grafts for patients. However, the only research that is federally funded are a few embryonic stem cell lines created from unused embryos at in vitro fertilization (IVF) clinics before 2001 (Dunn, 2005; “Embryonic & fetal research laws,” 2008; Therapeutic cloning, 2009). These lines are not enough to allow scientists to fully explore and take advantage of potential findings.
The creation of induced pluripotent stem cells by direct reprogramming has allowed for the circumvention of using embryonic stem cells while still leaving the cells with the ability to maintain pluripotency. Instead of ES cells which were originally derived from the epiblast of mouse embryos, IPS cells were generated from mouse embryonic fibroblasts. This eliminated both any ethical concerns for whether those cells were a living being or not and the need to destroy embryos at the blastocyst stage. An advantage of IPS cells is that they are derived from human somatic cells which makes them easy to acquire due to the possibility of using skin or blood cells. They can also be grown and differentiated individually for each person that the sample of somatic cells is taken from which eliminates the possibility of having any immune reaction and rejection to the differentiated cells during transplantation. These characteristics of IPS cells are important because they are what enables us to safely and accurately transform these affected cells from patients cells into neurons and confidently study them.
There are several new methods that have been developed since the start of the highly controversial stem cell debate which rectifies the major differences on both sides. New solutions such as Induced Pluripotent Stem Cells (iPS) acts as an alternate method to embryonic research in that it uses cellular reprogramming of adult skin cells.“The benefit of iPS is that stem cells can be created without the use of embryos, however, the cells resemble embryos in that they can, theoretically and under the appropriate conditions, be made to differentiate into any type of cell found in the body ” (Phillips, 2010). . There are also techniques being developed that use amnionic fluid, or stem cell extraction techniques that do not damage the embryo, that also provide alternatives for obtaining viable stem cell lines ” (Phillips, 2010). The only caveat to all of these newly developed alternatives is that no solution has been studied long enough to claim that it can be an effective substitute 100%. “To begin with, demand for
Mitchel C. Schiewe, PhD, Ovation Fertility™ Newport Beach Laboratory Director, has recently published a review paper about the development of various assisted reproductive technologies, or ART. Specifically, Dr. Schiewe reviews four technologies.
Stem cells have a plethora of side effects that over powers the benefits. The ability to differentiate is known as plasticity, and it is thought to only be at its greatest in embryonic stem cells. In order for the embryonic cells to be of use they must be fertilized, after which, the stem cell is removed, destroying the embryo. Stem cells can be used in adults; however it is believed through the consensus of the medical community that the plasticity of embryonic stem cells is not even closely matched by those of adult stem cells. The general idea is that “adult stem cells have a limited capacity to differentiate (Solter 8).” Adult stem cells are already stuck in their ways, which makes it useless, in a way. They can only reproduce the same cell type that they originate from. Thus, despite the prospecting medical leaps that this technology can provide, the process of how to obtain the embryonic stem cells overwhelms the benefits by far.
In the research that will be conducted at Harvard, if permission is granted, the growth of the blastocyst would be stopped and it would not be implanted into a woman’s womb. Stem cells would be extracted for study, destroying the embryo.
Human embryonic stem cells (ESCs) are pluripotent cells isolated from blastocysts, and are highly useful in studying human development (Itzkovitz-Eldor et al., 2000 p. 88). Although the National Institute of Health states that “it is not known if iPSCs and embryonic stem cells differ in clinically significant ways”, iPSCs are already being used to achieve the same results as ESCs in some applications without the use of embryos, removing the ethical concern associated with ESCs (National Institutes of Health, 2009). ESCs are capable of differentiating into all cell types, and can be used as a source of differentiated cells. In the report by Itskovitz-Eldor et al., they discuss the induced differentiation of ESCs in suspension into embryoid bodies, including the three embryonic germ layers. The authors state that “the ability to induce formation of human embryoid bodies that contain cells of neuronal, hematopoietic and cardiac origins will be useful in studying early human embryonic development” (Itzkovitz-Eldor et al., 2000 p. 88).