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Stem-cell Therapy
Stem-cell therapy is the use of stem cells to treat or prevent a disease or condition. , the only established therapy using stem cells is hematopoietic stem cell transplantation. This usually takes the form of a bone-marrow transplantation, but the cells can also be derived from umbilical cord blood. Research is underway to develop various sources for stem cells as well as to apply stem-cell treatments for neurodegenerative diseases and conditions such as diabetes and heart disease. Stem-cell therapy has become controversial following developments such as the ability of scientists to isolate and culture embryonic stem cells, to create stem cells using somatic cell nuclear transfer and their use of techniques to create induced pluripotent stem cells. This controversy is often related to abortion politics and to human cloning. Additionally, efforts to market treatments based on transplant of stored umbilical cord blood have been controversial. Medical uses For over 30 years ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stem Cells
In multicellular organisms, stem cells are undifferentiated or partially differentiated cells that can differentiate into various types of cells and proliferate indefinitely to produce more of the same stem cell. They are the earliest type of cell in a cell lineage. They are found in both embryonic and adult organisms, but they have slightly different properties in each. They are usually distinguished from progenitor cells, which cannot divide indefinitely, and precursor or blast cells, which are usually committed to differentiating into one cell type. In mammals, roughly 50–150 cells make up the inner cell mass during the blastocyst stage of embryonic development, around days 5–14. These have stem-cell capability. ''In vivo'', they eventually differentiate into all of the body's cell types (making them pluripotent). This process starts with the differentiation into the three germ layers – the ectoderm, mesoderm and endoderm – at the gastrulation stage. However, whe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hematopoiesis
Haematopoiesis (, from Greek , 'blood' and 'to make'; also hematopoiesis in American English; sometimes also h(a)emopoiesis) is the formation of blood cellular components. All cellular blood components are derived from haematopoietic stem cells. In a healthy adult person, approximately – new blood cells are produced daily in order to maintain steady state levels in the peripheral circulation.Semester 4 medical lectures at Uppsala University 2008 by Leif Jansson Process Haematopoietic stem cells (HSCs) Haematopoietic stem cells (HSCs) reside in the medulla of the bone (bone marrow) and have the unique ability to give rise to all of the different mature blood cell types and tissues. HSCs are self-renewing cells: when they differentiate, at least some of their daughter cells remain as HSCs so the pool of stem cells is not depleted. This phenomenon is called asymmetric division. The other daughters of HSCs (myeloid and lymphoid progenitor cells) can follow any of the othe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Immune-mediated Inflammatory Diseases
An immune-mediated inflammatory disease (IMID) is any of a group of conditions or diseases that lack a definitive etiology, but which are characterized by common inflammatory pathways leading to inflammation, and which may result from, or be triggered by, a dysregulation of the normal immune response. All IMIDs can cause end organ damage, and are associated with increased morbidity and/or mortality. Inflammation is an important and growing area of biomedical research and health care because inflammation mediates and is the primary driver of many medical disorders and autoimmune diseases, including ankylosing spondylitis, psoriasis, psoriatic arthritis, Behçet's disease, arthritis, inflammatory bowel disease (IBD), and allergy, as well as many cardiovascular, neuromuscular, and infectious diseases. Some current research even suggests that aging is a consequence, in part, of inflammatory processes. Characterization IMID is characterized by immune disregulation, and on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Autoimmune Disease
An autoimmune disease is a condition arising from an abnormal immune response to a functioning body part. At least 80 types of autoimmune diseases have been identified, with some evidence suggesting that there may be more than 100 types. Nearly any body part can be involved. Common symptoms can be diverse and transient, ranging from mild to severe, and generally include low grade fever and feeling tired. The cause is unknown. Some autoimmune diseases such as lupus run in families, and certain cases may be triggered by infections or other environmental factors. Some common diseases that are generally considered autoimmune include celiac disease, diabetes mellitus type 1, graves' disease, inflammatory bowel disease, multiple sclerosis, alopecia areata, addison’s disease, pernicious anemia, psoriasis, rheumatoid arthritis, and systemic lupus erythematosus. The diagnosis can be difficult to determine. Treatment depends on the type and severity of the condition. Nonstero ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Degenerative Disease
Degenerative disease is the result of a continuous process based on degenerative cell changes, affecting tissues or organs, which will increasingly deteriorate over time. In neurodegenerative diseases, cells of the central nervous system stop working or die via neurodegeneration. An example of this is Alzheimer's disease. The other two common groups of degenerative diseases are those that affect circulatory system (e.g. coronary artery disease) and neoplastic diseases (e.g. cancers). Many degenerative diseases exist and some are related to aging. Normal bodily wear or lifestyle choices (such as exercise or eating habits) may worsen degenerative diseases, but this depends on the disease. Sometimes the main or partial cause behind such diseases is genetic. Thus some are clearly hereditary like Huntington's disease. Sometimes the cause is viruses, poisons or other chemicals. The cause may also be unknown. Some degenerative diseases can be cured, but not always. It might still ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stem Cell Secretome
The stem cell secretome (also referred to as the stromal cell secretome) is a collective term for the paracrine soluble factors produced by stem cells and utilized for their inter-cell communication. In addition to inter-cell communication, the paracrine factors are also responsible for tissue development, homeostasis and (re-)generation. The stem cell secretome consists of extracellular vesicles, specifically exosomes, microvesicles, membrane particles, peptides and small proteins (cytokines). The paracrine activity of stem cells, i.e. the stem cell secretome, has been found to be the predominant mechanism by which stem cell-based therapies mediate their effects in degenerative, auto-immune and/or inflammatory diseases. Though not only stem cells possess a secretome which influences their cellular environment, their secretome currently appears to be the most relevant for therapeutic use. Extracellular Vesicles The Extracellular Vesicles are small partials that are normally ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paracrine Signalling
Paracrine signaling is a form of cell signaling, a type of cellular communication in which a cell produces a signal to induce changes in nearby cells, altering the behaviour of those cells. Signaling molecules known as paracrine factors diffuse over a relatively short distance (local action), as opposed to cell signaling by endocrine factors, hormones which travel considerably longer distances via the circulatory system; juxtacrine interactions; and autocrine signaling. Cells that produce paracrine factors secrete them into the immediate extracellular environment. Factors then travel to nearby cells in which the gradient of factor received determines the outcome. However, the exact distance that paracrine factors can travel is not certain. Although paracrine signaling elicits a diverse array of responses in the induced cells, most paracrine factors utilize a relatively streamlined set of receptors and pathways. In fact, different organs in the body - even between different speci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exosome (vesicle)
Exosomes are membrane-bound extracellular vesicles (EVs) that are produced in the endosomal compartment of most eukaryotic cells. The multivesicular body (MVB) is an endosome with intraluminal vesicles (ILVs) that bud inward into the endosomal lumen. If the MVB fuses with the cell surface (the plasma membrane), these ILVs are released as exosomes. In multicellular organisms, exosomes and other EVs were discovered in biological fluids including blood, urine and cerebrospinal fluid. Importantly, exosomes were also identified within the tissue matrix, coined Matrix-Bound Nanovesicles (MBV). They are also released ''in vitro'' by cultured cells into their growth medium. Since the size of exosomes is limited by that of the parent MVB, exosomes are generally thought to be smaller than most other EVs, from about 30 to 150 nanometres (nm) in diameter: around the same size as many lipoproteins but much smaller than cells. Compared with EVs in general, it is unclear whether exosome ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stem Cell Treatments
Stem-cell therapy is the use of stem cells to treat or prevent a disease or condition. , the only established therapy using stem cells is hematopoietic stem cell transplantation. This usually takes the form of a bone-marrow transplantation, but the cells can also be derived from umbilical cord blood. Research is underway to develop various sources for stem cells as well as to apply stem-cell treatments for neurodegenerative diseases and conditions such as diabetes and heart disease. Stem-cell therapy has become controversial following developments such as the ability of scientists to isolate and culture embryonic stem cells, to create stem cells using somatic cell nuclear transfer and their use of techniques to create induced pluripotent stem cells. This controversy is often related to abortion politics and to human cloning. Additionally, efforts to market treatments based on transplant of stored umbilical cord blood have been controversial. Medical uses For over 30 y ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limbal Stem Cell
Limbal stem cells, also known as corneal epithelial stem cells, are stem cells located in the basal epithelial layer of the corneal limbus. They form the border between the cornea and the sclera. Characteristics of limbal stem cells include a slow turnover rate, high proliferative potential, clonogenicity, expression of stem cell markers, as well as the ability to regenerate the entire corneal epithelium. Limbal stem cell proliferation has the role of maintaining the cornea; for example, by replacing cells that are lost via tears. Additionally, these cells also prevent the conjunctival epithelial cells from migrating onto the surface of the cornea. Medical conditions and treatments Damage to the limbus can lead to limbal stem cell deficiency (LSCD); this may be primary - related to an insufficient stromal microenvironment to support stem cell functions, such as aniridia, and other congenital conditions, or secondary – caused by external factors that destroy the limbal stem cells ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
European Medicines Agency
The European Medicines Agency (EMA) is an agency of the European Union (EU) in charge of the evaluation and supervision of medicinal products. Prior to 2004, it was known as the European Agency for the Evaluation of Medicinal Products or European Medicines Evaluation Agency (EMEA).Set up by EC Regulation No. 2309/93 as the European Agency for the Evaluation of Medicinal Products, and renamed by EC Regulation No. 726/2004 to the European Medicines Agency, it had the acronym EMEA until December 2009. The European Medicines Agency does not call itself EMA either – it has no official acronym but may reconsider if EMA becomes commonly accepted (secommunication on new visual identity an). The EMA was set up in 1995, with funding from the European Union and the pharmaceutical industry, as well as indirect subsidy from member states, its stated intention to harmonise (but not replace) the work of existing national medicine regulatory bodies. The hope was that this plan would not o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesenchymal Stem Cells
Mesenchymal stem cells (MSCs) also known as mesenchymal stromal cells or medicinal signaling cells are multipotent stromal cells that can differentiate into a variety of cell types, including osteoblasts (bone cells), chondrocytes (cartilage cells), myocytes (muscle cells) and adipocytes (fat cells which give rise to marrow adipose tissue). Structure Definition While the terms ''mesenchymal stem cell'' (MSC) and ''marrow stromal cell'' have been used interchangeably for many years, neither term is sufficiently descriptive: * Mesenchyme is embryonic connective tissue that is derived from the mesoderm and that differentiates into hematopoietic and connective tissue, whereas MSCs do not differentiate into hematopoietic cells. * Stromal cells are connective tissue cells that form the supportive structure in which the functional cells of the tissue reside. While this is an accurate description for one function of MSCs, the term fails to convey the relatively recently discove ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
