The 1900s brought upon more research in using stem cells.

However, a validated standardized protocol for differentiation of hESCs toward hepatocytes is currently not available, exact parameters that define the functionality of hepatic cells are lacking and the data differ among studies. Another problem is the high variability of cellular reference systems used by different authors and the poor description of these systems in some studies. Reference systems frequently used are hepatoma cell lines (such as HepG2, HuH7 and Alexander cells), foetal and adult liver cell extracts, and rat or human pHHs. Although pHHs were regularly used, data on the origin of pHHs (e.g. freshly isolated vs. cryoconserved, individual donor vs. hepatocyte pool, in-house prepared cells vs. commercially acquired cells, etc.), methods for hepatocyte cultivation and data on age, purity and characteristics of the specific hepatocyte preparation are often lacking. These problems complicate the comparison of hESC-derived hepatocyte-like cells with respect to their liver cell characteristics and hamper the assessment, whether specific protocols may be useful for efficient differentiation of functional hepatocytes from hESCs.

With enough research, stem cells can be a big help to the human kind.

Stem cell research, a relatively new field, investigates to improve and lengthen human life.

Stem cell research has incredible potential....

A self-replicating cell source, such as pluripotent stem cells, with the potential to differentiate into cardiomyocytes would represent an alternative in vitro system for cardiotoxicity. Earlier studies on murine ESC-derived cardiomyocytes have already demonstrated the potential of ESCs for safety pharmacology and toxicology (reviewed in Boheler et al. ; Wobus and Boheler ). Murine ESCs differentiating into the cardiac lineage yield several specialized cell types of the heart, such as atrial-, ventricular-, sinus nodal- and Purkinje-like cells. Cardiac-specific genes as well as proteins, receptors and ion channels are expressed in a developmentally controlled manner, which closely recapitulates the developmental pattern of early cardiogenesis in vivo (for reviews see Boheler et al. ; Filipczyk et al. ). Genetic manipulation, addition of extrinsic factors and extracellular matrix proteins, engineering the microenvironment as well as improvements in cultivation protocols have been shown to trigger the cardiac differentiation process and to increase the efficiency of cardiac differentiation (for reviews see Filipczyk et al. ; Chen et al. ; Perino et al. ; Puceat ; Reinecke et al. ; Horton et al. ). However, only human cell-based in vitro systems would overcome the problem of inter-species differences that limit the use of mESCs for cardiotoxicity testing. So far, much progress has been made in the differentiation of hESCs towards cardiomyocytes, and this knowledge is now being applied to hiPSCs. In the following sections, recent strategies for the generation of cardiomyocytes from human pluripotent stem cells, their characterization and methods for their enrichment will be summarized, and the potential of these cardiomyocytes in safety pharmacology and toxicology will be discussed.

Stem cell research is currently legal in most countries.

This act is considered to be murder by a great piece of the United States population, which has caused a crippling blow to stem cell research (as far as money and factual knowledge goes).

research papers examine the degenerative disorder of the human nervous system.
- Somatic cell nuclear transfer is also one of the main areas of study in stem cell research.

Ethics of stem cell research essays | Mirrors

Since the establishment of the first human pluripotent stem cell lines more than a decade ago the therapeutic potential of stem cells has been extensively discussed. Only in the more recent past, the unique potential of pluripotent stem cells in drug research and toxicology was realized. Pluripotent human stem cells could offer many benefits to this field, especially the perspective of an unlimited supply with human cells of well-defined origin, homogeneous characteristics and relevance to the human situation. While toxicological assays using murine PSCs are already performed routinely, human PSCs are still under investigation with respect to their suitability for these applications. However, proof-of-principle has been provided that these cells could make a valuable contribution to the technology platforms in safety pharmacology and toxicology. Especially in the field of developmental toxicology, hESCs represent a unique human-specific test system, although methodical questions remain to be solved, relevant endpoints must be identified and HTP screening methods still have to be developed.

In our modern day society, stem cell research has become a controversial topic.

Free stem cell Essays and Papers

To avail such advancements in stem cell research could see the alleviation or complete cure of afflictions that take the lives of millions worldwide each year.

- Sickle Cell Anemia Research Papers look at one of the most common inherited blood disorders.

FREE Ethics of Stem Cell Research Essay - ExampleEssays

Furthermore, the inclusion of additional endpoints of differentiation, specifically of the neural lineage, was requested by researchers and authorities (Spielmann et al. ). The rationale of using such systems is to correctly classify substances that were not identified as embryotoxic in the conventional EST. The inclusion of parameters for neuronal differentiation into the mEST allowed, for example, the classification of methylmercury as a highly embryotoxic substance in accordance with in vivo data, whereas the conventional EST failed to correctly classify this compound (Stummann et al. ). To further increase the number of molecular markers as endpoints of embryotoxicity testing, real-time Taqman RT-PCR analyses have been adopted for the EST in a pilot study (zur Nieden et al. ).