StemCell Therapy

A lot of patients suffering from colon cancer might well present no symptoms or signs during the earliest stages of the condition. When symptoms do eventually present, they can be many and varied, and can very much depend upon the size of the affliction, how far it has spread and also its actual location. It might be that some symptoms that present are as a result of a condition other than cancer itself, ranging from irritable bowel syndrome (IBS), inflammatory bowel disease (IBD) and occasionally diverticulosis. Also, such problems as abdominal pain or swelling can be symptomatic of colon problems and may well require further investigation.

You may also notice that, upon going to the lavatory, you have some blood in your stools, and this can be a symptom of cancer. Of course, having black poop doesnt ultimately mean that cancer is present. It can, however, also be indicative of other conditions and problems. For example, the kind of bright red blood that you may see on your toilet tissue could be as a result of hemorrhoids or anal fissures. It should also be remembered that various food items can also result in red poop, and these include beetroot and red liquorice. Some medications can also be culprits, and some can also turn the stools black-including iron supplements. Irrespective, any sign of blood or change in your stools should prompt you to seek advice from your GP, as it is always best to be sure that it is not a sign of a more serious condition, and with any cancer,early detection and treatment is essential to a successful recovery.

You should also note-if you are currently concerned-any change in the regularity of your stools-including whether or not they are more thin or irregular than usual-especially over a period of several weeks. Also, be mindful if you have diarrhea for several days in a row or, conversely, constipation.

You might also experience pain in your lower abdomen-including a feeling of hardness. You may also experience persistent pain or discomfort in your abdominal region, and this can include wind and cramps. You may also get the sensation that, when evacuating your bowels, that the bowel doesnt empty fully. Another symptom that you might recognize is colored stool mainly black stool, but could be green stool too. Also, if you have an iron deficiency (or anemia), it may be an indication that there is bleeding in your colon. Also, as in most cases and types of cancer, you should seek medical advice immediately if you experience any sudden and unexpected or unexplained weight loss, as this is one of the principal red flags. Also be aware of more vague, seemingly incidental symptoms, such as fatigue. IF you have a couple of symptoms and also feel fatigued for days in a row inexplicably, then this is also another warning sign and you should seek medical advice. It is important not to panic, but just to be aware of what might be going on.

Remember, cases of colon cancer account for around 90% of all cases of intestinal cancers, and also account for more deaths every year of men and women from cancer. Early treatment is an absolute must.

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Nanomedicine, bionanotechnology | NanomedicineCenter.com

Table of Contents

The physical carrier of inheritance | The structure of DNA | DNA Replication

While the period from the early 1900s to World War II has been considered the "golden age" of genetics, scientists still had not determined that DNA, and not protein, was the hereditary material. However, during this time a great many genetic discoveries were made and the link between genetics and evolution was made.

Friedrich Meischer in 1869 isolated DNA from fish sperm and the pus of open wounds. Since it came from nuclei, Meischer named this new chemical, nuclein. Subsequently the name was changed to nucleic acid and lastly to deoxyribonucleic acid (DNA). Robert Feulgen, in 1914, discovered that fuchsin dye stained DNA. DNA was then found in the nucleusof all eukaryoticcells.

During the 1920s, biochemist P.A. Levene analyzed the components of the DNA molecule. He found it contained four nitrogenous bases: cytosine, thymine, adenine, and guanine; deoxyribose sugar; and a phosphate group. He concluded that the basic unit (nucleotide) was composed of a base attached to a sugar and that the phosphate also attached to the sugar. He (unfortunately) also erroneously concluded that the proportions of bases were equal and that there was a tetranucleotide that was the repeating structure of the molecule. The nucleotide, however, remains as the fundemantal unit (monomer) of the nucleic acid polymer. There are four nucleotides: those with cytosine (C), those with guanine (G), those with adenine (A), and those with thymine (T).

Molecular structure of three nirogenous bases. In this diagram there are three phosphates instead of the single phosphate found in the normal nucleotide. Images from Purves et al., Life: The Science of Biology, 4th Edition, by Sinauer Associates (www.sinauer.com) and WH Freeman (www.whfreeman.com), used with permission.

During the early 1900s, the study of genetics began in earnest: the link between Mendel's work and that of cell biologists resulted in the chromosomal theory of inheritance; Garrod proposed the link between genes and "inborn errors of metabolism"; and the question was formed: what is a gene? The answer came from the study of a deadly infectious disease: pneumonia. During the 1920s Frederick Griffith studied the difference between a disease-causing strain of the pneumonia causing bacteria (Streptococcus peumoniae) and a strain that did not cause pneumonia. The pneumonia-causing strain (the S strain) was surrounded by a capsule. The other strain (the R strain) did not have a capsule and also did not cause pneumonia. Frederick Griffith (1928) was able to induce a nonpathogenic strain of the bacterium Streptococcus pneumoniae to become pathogenic. Griffith referred to a transforming factor that caused the non-pathogenic bacteria to become pathogenic. Griffith injected the different strains of bacteria into mice. The S strain killed the mice; the R strain did not. He further noted that if heat killed S strain was injected into a mouse, it did not cause pneumonia. When he combined heat-killed S with Live R and injected the mixture into a mouse (remember neither alone will kill the mouse) that the mouse developed pneumonia and died. Bacteria recovered from the mouse had a capsule and killed other mice when injected into them!

Hypotheses:

1. The dead S strain had been reanimated/resurrected.

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DNA and Molecular Genetics - Estrella Mountain Community ...

Genetics of Human Longevity: New Ideas & Findings

Natalia Gavrilova

Center on Aging, NORC at the University of Chicago

(Abstract of presentation at the International Conference on Longevity, Sydney, Australia, March 5-7, 2004)

In contrast to the remarkable progress in the genetics of yeast and nematode aging, little is known about genes that control human longevity. What is behind the records of extreme human longevity: just lucky chance, favorable environment, or 'good' genes? How to resolve the apparent controversy between strong familial clustering of human longevity, and poor resemblance in lifespan among blood relatives?

We applied methods of genetic epidemiology and survival analysis to family-linked data on human lifespan. Special efforts were undertaken to collect detailed and reliable human genealogies an important data source for genetic studies of human longevity. We found that the dependence of offspring lifespan on parental lifespan is essentially non-linear, with very weak resemblance before parental lifespan of 80 years and very steep offspring-parent dependence (high narrow-sense heritability) for longer lived parents. There is no correlation between lifespan of spouses, who share familial environment. These observations suggest that chances to survive beyond age 80 are significantly influenced by genetic factors rather than shared familial environment. These findings explain the existing longevity paradox: although the heritability estimates for lifespan are rather low, the exceptional longevity has a strong familial association.

We also tested the prediction of mutation theory of aging that accumulation of mutations in parental germ cells may affect progeny lifespan when progeny was conceived to older parents. We found that daughters conceived to older fathers live shorter lives, while sons are not affected. Maternal age effects on lifespan of adult progeny are negligible compared to effects of paternal age, which is consistent with the notion of higher rates of DNA copy-errors in paternal germ cells caused by more intensive cell divisions during spermatogenesis.

Genealogical data also are useful for testing the prediction of the disposable soma theory that human longevity comes with the cost of impaired reproductive success. We found that in contrast to previous reports by other authors, woman's exceptional longevity is not associated with infertility. Thus, the concept of heavy infertility cost for human longevity is not supported by data, when these data are carefully cross-checked, cleaned and reanalyzed. These results demonstrate the importance of high quality genealogical data for genetic studies of human longevity.

Relevant Publications:

Gavrilov, L.A., Gavrilova, N.S. Early-life factors modulating lifespan. In: Rattan, S.I.S. (Ed.).Modulating Aging and Longevity. Kluwer Academic Publishers, Dordrecht, The Netherlands, 2003, 27-50.

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Genetics of Human Longevity - Longevity Science

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In July last year I wrote about some fairly glaring flaws in a paper published in Science on the genetics of extreme longevity. At the time, potential problems with the paper had been flagged in an excellent Newsweek piece by Mary Carmichael.

Today, after a year in advance online limbo without ever progressing to the print edition of the journal, and a formal Expression of Concern last November, the paper was fully retracted. Theres solid coverage of the announcement at the Boston Globe (including quotes from my Genomes Unzipped colleague Jeff Barrett), Nature, and of course the superb Retraction Watch.

Heres the retraction notice in full:

After online publication of our Report Genetic signatures of exceptional longevity in humans (1), we discovered that technical errors in the Illumina 610 array and an inadequate quality control protocol introduced false-positive single-nucleotide polymorphisms (SNPs) in our findings. An independent laboratory subsequently performed stringent quality control measures, ambiguous SNPs were then removed, and resultant genotype data were validated using an independent platform. We then reanalyzed the reduced data set using the same methodology as in the published paper. We feel the main scientific findings remain supported by the available data: (i) A model consisting of multiple specific SNPs accurately differentiates between centenarians and controls; (ii) genetic profiles cluster into specific signatures; and (iii) signatures are associated with ages of onset of specific age-related diseases and subjects with the oldest ages. However, the specific details of the new analysis change substantially from those originally published online to the point of becoming a new report. Therefore, we retract the original manuscript and will pursue alternative publication of the new findings.

In a statement quoted over at Retraction Watch, the journal makes it more clear how the retraction decision was actually reached:

Sebastiani and colleagues submitted the corrected data to Science in December 2010, where the work underwent careful peer-review. Although the authors remain confident about their findings, Science has concluded on the basis of peer-review that a paper built on the corrected data would not meet the journals standards for genome-wide association studies. One such standard, for example, is the inclusion of a reliable replication sample that shows comparable results to those in the initial experiments.

The authors have therefore agreed to retract their paper.

In other words, the authors were still willing to stand by their results, but the journal wasnt.

Questions remain about how the study managed to pass through peer review in the first place virtually every complex trait geneticist I spoke to was immediately, massively skeptical about the articles findings from the moment of publication but it appears that Science has conducted a thorough investigation of the authors amended manuscript and made an appropriate decision. It will be intriguing to see if, when and in what form the studys authors manage to republish their results.

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Longevity genetics study retracted from Science | WIRED

Stem Cells

A stem cell is essentially a blank cell, capable of becoming another more differentiated cell type in the body, such as a skin cell, a muscle cell, or a nerve cell. Microscopic in size, stem cells are big news in medical and science circles because they can be used to replace or even heal damaged tissues and cells in the body. They can serve as a built-in repair system for the human body, replenishing other cells as long as a person is still alive.

Adult stem cells are a natural solution. They naturally exist in our bodies, and they provide a natural repair mechanism for many tissues of our bodies. They belong in the microenvironment of an adult body, while embryonic stem cells belong in the microenvironment of the early embryo, not in an adult body, where they tend to cause tumors and immune system reactions.

Most importantly, adult stem cells have already been successfully used in human therapies for many years. As of this moment, no therapies in humans have ever been successfully carried out using embryonic stem cells. New therapies using adult type stem cells, on the other hand, are being developed all the time.

Source: 2010 Stemcellresearchfacts.org

Cloning-to-produce-children Production of a cloned human embryo, formed for the (proximate) purpose of initiating a pregnancy, with the (ultimate) goal of producing a child who will be genetically virtually identical to a currently existing or previously existing individual.

Cloning-for-biomedical-research - Production of a cloned human embryo, formed for the (proximate) purpose of using it in research or for extracting its stem cells, with the (ultimate) goals of gaining scientific knowledge of normal and abnormal development and of developing cures for human diseases.

Human cloning The asexual reproduction of a new human organism that is, at all stages of development, genetically virtually identical to a currently existing, or previously existing, human being. (CR)

Cloned embryo: An embryo arising from the somatic cell nuclear transfer process as contrasted with an embryo arising from the union of an egg and sperm. (CR)

Source: White Paper: Alternative Sources of Pluripotent Stem Cells The Presidents Council on Bioethics Washington, D.C., May 2005

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Stem Cells and Cloning | New Jersey Right to Life ...

Stem cell laws are the law rules, and policy governance concerning the sources, research, and uses in treatment of stem cells in humans. These laws have been the source of much controversy and vary significantly by country.[1] In the European Union, stem cell research using the human embryo is permitted in Sweden, Finland, Belgium, Greece, Britain, Denmark and the Netherlands; however, it is illegal in Germany, Austria, Ireland, Italy, and Portugal. The issue has similarly divided the United States, with several states enforcing a complete ban and others giving financial support.[2] Elsewhere, Japan, India, Iran, Israel, South Korea, China, and Australia are supportive. However, New Zealand, most of Africa (except South Africa), and most of South America (except Brazil) are restrictive.

The information presented here covers the legal implications of embryonic stem cells (ES), rather than induced pluripotent stem cells (iPSCs). The laws surrounding the two differ because while both have similar capacities in differentiation, their modes of derivation are not. While embryonic stem cells are taken from embryoblasts, induced pluripotent stem cells are undifferentiated from somatic adult cells.[3]

Stem cell are cells found in most, if not all, multi-cellular organisms. A common example of a stem cell is the Hematopoietic stem cell (HSC) which are multipotent stem cells that give rise to cells of the blood lineage. In contrast to multipotent stem cells, embryonic stem cells are pluripotent and are thought to be able to give rise to all cells of the body. Embryonic stem cells were isolated in mice in 1981, and in humans in 1998.[4]

Stem cell treatments are a type of cell therapy that introduce new cells into adult bodies for possible treatment of cancer, Somatic cell nuclear transfer, diabetes, and other medical conditions. Cloning also might be done with stem cells. Stem cells have been used to repair tissue damaged by disease.[5]

Because Embryonic Stem (ES) cells are cultured from the embryoblast 45 days after fertilization, harvesting them is most often done from donated embryos from in vitro fertilization (IVF) clinics. In January 2007, researchers at Wake Forest University reported that "stem cells drawn from amniotic fluid donated by pregnant women hold much of the same promise as embryonic stem cells."[4]

In 2000, the NIH, under the administration of President Bill Clinton, issued guidelines that allow federal funding of embryonic stem-cell research.[4]

The European Union has yet to issue consistent regulations with respect to stem cell research in member states. Whereas Germany, Austria, Italy, Finland, Greece, Ireland, Portugal and the Netherlands prohibit or severely restrict the use of embryonic stem cells, Sweden and the United Kingdom have created the legal basis to support this research.[6]Belgium bans reproductive cloning but allows therapeutic cloning of embryos.[1]France prohibits reproductive cloning and embryo creation for research purposes, but enacted laws (with a sunset provision expiring in 2009) to allow scientists to conduct stem cell research on imported a large amount of embryos from in vitro fertilization treatments.[1]Germany has restrictive policies for stem cell research, but a 2008 law authorizes "the use of imported stem cell lines produced before May 1, 2007."[1]Italy has a 2004 law that forbids all sperm or egg donations and the freezing of embryos, but allows, in effect, using existing stem cell lines that have been imported.[1]Sweden forbids reproductive cloning, but allows therapeutic cloning and authorized a stem cell bank.[1][6]

In 2001, the British Parliament amended the Human Fertilisation and Embryology Act 1990 (since amended by the Human Fertilisation and Embryology Act 2008) to permit the destruction of embryos for hESC harvests but only if the research satisfies one of the following requirements:

The United Kingdom is one of the leaders in stem cell research, in the opinion of Lord Sainsbury, Science and Innovation Minister for the UK.[7] A new 10 million stem cell research centre has been announced at the University of Cambridge.[8]

The primary legislation in South Africa that deals with embryo research is the Human Tissue Act, which is set to be replaced by Chapter 8 of the National Health Act. The NHA Chapter 8 has been enacted by parliament, but not yet signed into force by the president. The process of finalising these regulations is still underway. The NHA Chapter 8 allows the Minister of Health to give permission for research on embryos not older than 14 days. The legislation on embryo research is complemented by the South African Medical Research Council's Ethics Guidelines. These Guidelines advise against the creation of embryos for the sole purpose of research. In the case of Christian Lawyers Association of South Africa & others v Minister of Health & others[9] the court ruled that the Bill of Rights is not applicable to the unborn. It has therefore been argued based on constitutional grounds (the right to human dignity, and the right to freedom of scientific research) that the above limitations on embryo research are overly inhibitive of the autonomy of scientists, and hence unconstitutional.[10]

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Stem cell laws - Wikipedia, the free encyclopedia

Andrew Weil, M.D., is the world's leading proponent of alternative medicine, right?

Wrong.

Although this is how the popular media often portrays him, Dr. Weil is actually the world's leading proponent of integrative medicine, a philosophy that is considerably different from a blanket endorsement of alternative medicine. To fully understand Dr. Weil's advice - presented in his Web sites, bestselling books and lectures, and reflected in the daily practice of thousands of physicians worldwide - it's important to grasp what integrative medicine is, and is not.

The first step is mastering some basic terms.

Using synthetic drugs and surgery to treat health conditions was known just a few decades ago as, simply, "medicine." Today, this system is increasingly being termed "conventional medicine." This is the kind of medicine most Americans still encounter in hospitals and clinics. Often both expensive and invasive, it is also very good at some things; for example, handling emergency conditions such as massive injury or a life-threatening stroke. Dr. Weil is unstinting in his appreciation for conventional medicine's strengths. "If I were hit by a bus," he says, "I'd want to be taken immediately to a high-tech emergency room." Some conventional medicine is scientifically validated, some is not.

Any therapy that is typically excluded by conventional medicine, and that patients use instead of conventional medicine, is known as "alternative medicine." It's a catch-all term that includes hundreds of old and new practices ranging from acupuncture to homeopathy to iridology. Generally alternative therapies are closer to nature, cheaper and less invasive than conventional therapies, although there are exceptions. Some alternative therapies are scientifically validated, some are not. An alternative medicine practice that is used in conjunction with a conventional one is known as a "complementary" medicine. Example: using ginger syrup to prevent nausea during chemotherapy. Together, complementary and alternative medicines are often referred to by the acronym CAM.

Enter integrative medicine. As defined by the National Center for Complementary and Alternative Medicine at the National Institutes of Health, integrative medicine "combines mainstream medical therapies and CAM therapies for which there is some high-quality scientific evidence of safety and effectiveness."

In other words, integrative medicine "cherry picks" the very best, scientifically validated therapies from both conventional and CAM systems. In his New York Times review of Dr. Weil's latest book, "Healthy Aging: A Lifelong Guide to Your Physical and Spiritual Well-Being," Abraham Verghese, M.D., summed up this orientation well, stating that Dr. Weil, "doesn't seem wedded to a particular dogma, Western or Eastern, only to the get-the-patient-better philosophy."

So this is a basic definition of integrative medicine. What follows is the complete one, which serves to guide both Dr. Weil's work and that of integrative medicine physicians and teachers around the world:

See more here:
What is Integrative Medicine? - Andrew Weil, M.D.

Without it, we would all be forced to live in sterile environments, never touching each other, never feeling a spring breeze, never tasting rain. The immune system is that complex operation within our bodies that keeps us healthy and disease-free.

Few systems in nature are as complicated as the human immune system. It exists apart from, and works in concert with, every other system in the body. When it works, people stay healthy. When it malfunctions, terrible things happen.

The main component of the system is the lymphatic system. Small organs called lymph nodes help carry lymph fluid throughout the body. These nodes are located most prominently in the throat, armpit and groin. Lymph fluid contains lymphocytes and other white blood cells and circulates throughout the body.

The white blood cells are the main fighting soldiers in the body's immune system. They destroy foreign or diseased cells in an effort to clear them from the body. This is why a raised white blood cell count is often an indication of infection. The worse the infection, the more white blood cells the body sends out to fight it.

White and red blood cells are produced in the spongy tissue called bone marrow. This substance, rich in nutrients, is crucial for properly functioning immunity. Leukemia, a cancer of the bone marrow, causes greatly increased production of abnormal white blood cells and allows immature red blood cells to be released into the body. Other features, such as the lowly nose hair and mucus lining in the lungs, help trap bacteria before it gets into the bloodstream to cause an infection.

B cells and T cells are the main kinds of lymphocytes that attack foreign cells. B cells produce antibodies tailored to different cells at the command of the T cells, the regulators of the body's immune response. T cells also destroy diseased cells.

Many diseases that plague mankind are a result of insufficient immunity or inappropriate immune response. A cold, for instance, is caused by a virus. The body doesn't recognize some viruses as being harmful, so the T cell response is, "Pass, friend," and the sneezing begins.

Allergies are examples of inappropriate immune response. The body is hyper-vigilant, seeing that evil pollen as a dangerous invader instead of a harmless yellow powder. Other diseases, such as diabetes and AIDS, suppress the immune system, reducing the body's ability to fight infection.

Vaccines are vital in helping the body fend off certain diseases. The body is injected with a weakened or dead form of the virus or bacteria and produces the appropriate antibodies, giving complete protection against the full-strength form of the disease. This is the reason such disorders as diphtheria, mumps, tetanus and pertussis are so rarely seen today. Children have been vaccinated against them, and the immune system is on the alert. Vaccines have also been instrumental in eradicating plagues such as smallpox and polio.

Antibiotics help the body fight disease as well, but doctors are more cautious about prescribing the broad-spectrum variety, since certain bacteria are starting to show resistance to them. The next time you hug a loved one or smell a rose, thank your immune system.

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What Is the Immune System? (with pictures)

genetics,study of heredity in general and of genes in particular. Genetics forms one of the central pillars of biology and overlaps with many other areas such as agriculture, medicine, and biotechnology.

Since the dawn of civilization, humankind has recognized the influence of heredity and has applied its principles to the improvement of cultivated crops and domestic animals. A Babylonian tablet more than 6,000 years old, for example, shows pedigrees of horses and indicates possible inherited characteristics. Other old carvings show cross-pollination of date palm trees. Most of the mechanisms of heredity, however, remained a mystery until the 19th century, when genetics as a systematic science began.

Genetics arose out of the identification of genes, the fundamental units responsible for heredity. Genetics may be defined as the study of genes at all levels, including the ways in which they act in the cell and the ways in which they are transmitted from parents to offspring. Modern genetics focuses on the chemical substance that genes are made of, called deoxyribonucleic acid, or DNA, and the ways in which it affects the chemical reactions that constitute the living processes within the cell. Gene action depends on interaction with the environment. Green plants, for example, have genes containing the information necessary to synthesize the photosynthetic pigment chlorophyll that gives them their green colour. Chlorophyll is synthesized in an environment containing light because the gene for chlorophyll is expressed only when it interacts with light. If a plant is placed in a dark environment, chlorophyll synthesis stops because the gene is no longer expressed.

Genetics as a scientific discipline stemmed from the work of Gregor Mendel in the middle of the 19th century. Mendel suspected that traits were inherited as discrete units, and, although he knew nothing of the physical or chemical nature of genes at the time, his units became the basis for the development of the present understanding of heredity. All present research in genetics can be traced back to Mendels discovery of the laws governing the inheritance of traits. The word genetics was introduced in 1905 by English biologist William Bateson, who was one of the discoverers of Mendels work and who became a champion of Mendels principles of inheritance.

Although scientific evidence for patterns of genetic inheritance did not appear until Mendels work, history shows that humankind must have been interested in heredity long before the dawn of civilization. Curiosity must first have been based on human family resemblances, such as similarity in body structure, voice, gait, and gestures. Such notions were instrumental in the establishment of family and royal dynasties. Early nomadic tribes were interested in the qualities of the animals that they herded and domesticated and, undoubtedly, bred selectively. The first human settlements that practiced farming appear to have selected crop plants with favourable qualities. Ancient tomb paintings show racehorse breeding pedigrees containing clear depictions of the inheritance of several distinct physical traits in the horses. Despite this interest, the first recorded speculations on heredity did not exist until the time of the ancient Greeks; some aspects of their ideas are still considered relevant today.

Hippocrates (c. 460c. 375 bce), known as the father of medicine, believed in the inheritance of acquired characteristics, and, to account for this, he devised the hypothesis known as pangenesis. He postulated that all organs of the body of a parent gave off invisible seeds, which were like miniaturized building components and were transmitted during sexual intercourse, reassembling themselves in the mothers womb to form a baby.

Aristotle (384322 bce) emphasized the importance of blood in heredity. He thought that the blood supplied generative material for building all parts of the adult body, and he reasoned that blood was the basis for passing on this generative power to the next generation. In fact, he believed that the males semen was purified blood and that a womans menstrual blood was her equivalent of semen. These male and female contributions united in the womb to produce a baby. The blood contained some type of hereditary essences, but he believed that the baby would develop under the influence of these essences, rather than being built from the essences themselves.

Aristotles ideas about the role of blood in procreation were probably the origin of the still prevalent notion that somehow the blood is involved in heredity. Today people still speak of certain traits as being in the blood and of blood lines and blood ties. The Greek model of inheritance, in which a teeming multitude of substances was invoked, differed from that of the Mendelian model. Mendels idea was that distinct differences between individuals are determined by differences in single yet powerful hereditary factors. These single hereditary factors were identified as genes. Copies of genes are transmitted through sperm and egg and guide the development of the offspring. Genes are also responsible for reproducing the distinct features of both parents that are visible in their children.

In the two millennia between the lives of Aristotle and Mendel, few new ideas were recorded on the nature of heredity. In the 17th and 18th centuries the idea of preformation was introduced. Scientists using the newly developed microscopes imagined that they could see miniature replicas of human beings inside sperm heads. French biologist Jean-Baptiste Lamarck invoked the idea of the inheritance of acquired characters, not as an explanation for heredity but as a model for evolution. He lived at a time when the fixity of species was taken for granted, yet he maintained that this fixity was only found in a constant environment. He enunciated the law of use and disuse, which states that when certain organs become specially developed as a result of some environmental need, then that state of development is hereditary and can be passed on to progeny. He believed that in this way, over many generations, giraffes could arise from deerlike animals that had to keep stretching their necks to reach high leaves on trees.

British naturalist Alfred Russel Wallace originally postulated the theory of evolution by natural selection. However, Charles Darwins observations during his circumnavigation of the globe aboard the HMS Beagle (183136) provided evidence for natural selection and his suggestion that humans and animals shared a common ancestry. Many scientists at the time believed in a hereditary mechanism that was a version of the ancient Greek idea of pangenesis, and Darwins ideas did not appear to fit with the theory of heredity that sprang from the experiments of Mendel.

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genetics | Britannica.com

Genetic engineering is a set of technologies used to change the genetic makeup of cells, including thetransfer of genes within and across species boundaries to produce improved or novel organisms. The techniques involve sophisticated manipulations of genetic material and other biologically important chemicals.

Genes are the chemical blueprints that determine an organism's traits. Moving genes from one organism to another transfers those traits. Through genetic engineering, organisms can be given targeted combinations of new genesand therefore new combinations of traitsthat do not occur in nature and, indeed, cannot be developed by natural means. Such an approach is different from classical plant and animal breeding, which operates through selection across many generations for traits of interest. Classical breeding operates on traits, only indirectly selecting genes, whereas biotechnology targets genes, attempting to influence traits. The potential of biotechnology is to rapidly accelerate the rate of progress and efficiency of breeding.

Novel organisms

Nature can produce organisms with new gene combinations through sexual reproduction. A brown cow bred to a yellow cow may produce a calf of a completely new color. But reproductive mechanisms limit the number of new combinations. Cows must breed with other cows (or very near relatives). A breeder who wants a purple cow would be able to breed toward one only if the necessary purple genes were available somewhere in a cow or a near relative to cows. A genetic engineer has no such restriction. If purple genes are available anywhere in naturein a sea urchin or an iristhose genes could be used in attempts to produce purple cows. This unprecedented ability to shuffle genes means that genetic engineers can concoct gene combinations that would never be found in nature.

New risks

Genetic engineering is therefore qualitatively different from existing breeding technologies. It is a set of technologies for altering the traits of living organisms by inserting genetic material that has been manipulated to extract it from its source and successfully insert it in functioning order in target organisms. Because of this, genetic engineering may one day lead to the routine addition of novel genes that have been wholly synthesized in the laboratory.

In addition to desired benefits, novel organisms may bring novel risks as well. These risks must be carefully assessed to make sure that all effectsboth desired and unintendedare benign. UCS advocates caution, examination of alternatives, and careful, contextual, case-by-case evaluation of genetic enginering applications within an overall framework that moves agricultural systems of food production toward sustainability.

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What Is Genetic Engineering? | Union of Concerned Scientists

Fat Stem Cell Therapy: The Impacts of Aging, Disease, and Weight on Cells

Fat stem cell therapy continues to explode, with literally 20 new clinics popping up every week. I blogged awhile back that fat stem cells taken from overweight patients are not as potent as fat taken from thinner patients. Three new studies published this past few months add to that discussion. The focus of the recent investigations are how disease, aging, and weight impacts fat stem cells.

The first study looked at fat stem cells from patients with cardiovascular disease. First the good news, when fat stem cells from older patients with heart disease were compared to those from older patients without heart disease, there wasnt a difference in the ability of the fat stem cells to make new blood vessels. Now the bad news, fat stem cells from older patients in both categories were less able to make new blood vessels when compared to fat stem cells from younger patients.

The second study also looked at fat stem cells and aging. The money shot graph from that paper is above. Regrettably this study wasnt very sophisticated and made little effort to look at stem cell quality like the first. They also only looked at the nucleated cell count in the fat, which is a very rough metric of the stem cells in the fat (only a very small portion of the nucleated cells are stem cells). For more information on what these numbers mean, see my Doctor-Patient Guide to what stem cell numbers mean. What did they find? This rough metric of a fat stem cell count declined substantially after age 40. After that age, it dropped to a bit more than half of the value that they found in women under 40.

Finally, a third interesting study looked at the lifespan of fat stem cells from normal weight, obese, and post bariatric surgery patients. Interestingly, the stem cells from obese patients had a shorter lifespan and were less healthy than either the stem cells from the normal weight or post weight loss surgery patients. Basically, being overweight hurt the DNA of the fat stem cells.

The upshot? Fat stem cells are impacted by aging and being overweight. Being older and heavy is likely a double whammy for your cells. While some of these issues can be dealt with via dosing (administer more fat stem cells), the third study showed that cellular DNA damage was accumulating in the fat stem cells of patients who were overweight. Therefore solving the issue in some patients may not be as easy as just increasing the dose.

If you liked this post, you may really enjoy this book by the same author - Dr. Chris Centeno

Written by Regenexx Founder, Dr. Chris Centeno, this 150 page book explains the Regenexx approach to patients and orthopedic conditions. Whether youre are an existing patient or simply interested in the human body and how everything in the body ties together, you will enjoy exploring this book in-depth. With hyperlinks to more detailed information, related studies and commentary, this book condenses a huge amount of data and resources into an enjoyable and entertaining read.

Chris Centeno, M.D. is a specialist in regenerative medicine and the new field of Interventional Orthopedics.

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Fat Stem Cell Therapy: The Impacts of Aging, Disease, and ...

Ive blogged before on the stem cell wild west, or the concept that theres more misinformation on stem cells these days for patients and physicians than good information. Many colleagues act surprised when I tell them the FDA considers the stem cells that they are isolating from fat in their office an illegal unapproved drug. I then have to explain loads of information to them, so I thought that instead Id write a blog post about the topic and give everyone a link.

First, so far, looking at all of the data published by FDA and the existing and planned regulations, same day stem cell procedures using bone marrow dont seem to be impacted by any FDA rule changes. Second,for a much more detailed (and boring) technical discussion on the topic, see my recent paper published in the AAPMR journal. Ive also published another similar paper in the same journal (link here). Third, I have long disagreed with the FDAs position to regulate fat stem cells as a drug, as both papers describe. Having said that, the FDA gets to create the rules on this issue, so dont kill the messenger.

So whats the evidence that the FDA considers fat stem cells created at the bedside an unapproved drug? To understand this, you first have to understand that the agency created a line in the sand approach called manipulation. If what you do to cells crosses this line, then the cells (even those from the same patient and even if what you do occurs in the same surgical procedure in the doctors office) are considered a drug. TheFDA began making its position clear on this issue in 2011. The agency was asked by physicians wishing to process fat at the bedside to obtain stem cells to treat knee arthritis whether the process would make the cells a drug or would covered under the practice of medicine (i.e. not a drug). As you can see from reading the FDA response linked above, the FDA considered the cells a drug. A very similar response was obtained when a Maryland plastic surgeon asked if fat processed in his office to obtain stem cells for a cosmetic procedure would be a drug.

If the two above letters left any doubt in anyones mind that the FDA considered fat stem cells a drug, more recently, the FDA has issued several draft guidances to spell out its position. The most recent document seems to be aimedsquarely at doctors who believe that processing the patients own fat stem cells in their office isntthe manufacture of an illegal drug, but rather just the routine practice of medicine.

So heres a quote from that document:

Processing to isolate non-adipocyte or non-structural components from adipose tissue (with or without subsequent cell culture or expansion) is generally considered more than minimal manipulation. This is because the connective tissue and structural components of the adipose tissue are entirely removed from the non-adipocyte or non-structural isolates, thereby altering the original relevant characteristics relating to the tissues utility for reconstruction, repair, or replacement.

Still not clear? Try this paragraph:

Example A-1: Adipose tissue is recovered by tumescent liposuction. The adipose tissue undergoes processing or manipulation (e.g., enzymatic digestion, mechanical disruption, etc.) to isolate cellular components, commonly referred to as stromal vascular fraction, which is considered a potential source of adipose-derived stromal/stem cells for clinical therapeutic uses. This processing breaks down and eliminates the structural components that function to provide cushioning and support, thereby altering the original relevant characteristics of the HCT/P relating to its utility for reconstruction, repair, or replacement. Therefore, based on the definition of minimal manipulation for structural tissue, this processing would generally be considered more than minimal manipulation.

I can just hear the peanut gallery now, shouting, but wait, Im still covered as a doctor under the same surgical procedure exemption (21 CFR 1271.15(b))! What does this mean? The FDA carves out an exemption from the drug regulations for doctors who minimally process tissue during the same surgical procedure.

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Are Fat Stem Cells a Drug? - Regenexx

Visual perception is the ability to interpret the surrounding environment by processing information that is contained in visible light. The resulting perception is also known as eyesight, sight, or vision (adjectival form: visual, optical, or ocular). The various physiological components involved in vision are referred to collectively as the visual system, and are the focus of much research in psychology, cognitive science, neuroscience, and molecular biology, collectively referred to as vision science.

The visual system in animals allows individuals to assimilate information from their surroundings. The act of seeing starts when the lens of the eye focuses an image of its surroundings onto a light-sensitive membrane in the back of the eye, called the retina. The retina is actually part of the brain that is isolated to serve as a transducer for the conversion of patterns of light into neuronal signals. The lens of the eye focuses light on the photoreceptive cells of the retina, which detect the photons of light and respond by producing neural impulses. These signals are processed in a hierarchical fashion by different parts of the brain, from the retina upstream to central ganglia in the brain.

Note that up until now much of the above paragraph could apply to octopi, mollusks, worms, insects and things more primitive; anything with a more concentrated nervous system and better eyes than say a jellyfish. However, the following applies to mammals generally and birds (in modified form): The retina in these more complex animals sends fibers (the optic nerve) to the lateral geniculate nucleus, to the primary and secondary visual cortex of the brain. Signals from the retina can also travel directly from the retina to the superior colliculus.

The perception of objects and the totality of the visual scene is accomplished by the visual association cortex. The visual association cortex combines all sensory information perceived by the striate cortex which contains thousands of modules that are part of modular neural networks. The neurons in the striate cortex send axons to the extrastriate cortex, a region in the visual association cortex that surrounds the striate cortex.[1]

The major problem in visual perception is that what people see is not simply a translation of retinal stimuli (i.e., the image on the retina). Thus people interested in perception have long struggled to explain what visual processing does to create what is actually seen.

There were two major ancient Greek schools, providing a primitive explanation of how vision is carried out in the body.

The first was the "emission theory" which maintained that vision occurs when rays emanate from the eyes and are intercepted by visual objects. If an object was seen directly it was by 'means of rays' coming out of the eyes and again falling on the object. A refracted image was, however, seen by 'means of rays' as well, which came out of the eyes, traversed through the air, and after refraction, fell on the visible object which was sighted as the result of the movement of the rays from the eye. This theory was championed by scholars like Euclid and Ptolemy and their followers.

The second school advocated the so-called 'intro-mission' approach which sees vision as coming from something entering the eyes representative of the object. With its main propagators Aristotle, Galen and their followers, this theory seems to have some contact with modern theories of what vision really is, but it remained only a speculation lacking any experimental foundation.

Both schools of thought relied upon the principle that "like is only known by like", and thus upon the notion that the eye was composed of some "internal fire" which interacted with the "external fire" of visible light and made vision possible. Plato makes this assertion in his dialogue Timaeus, as does Aristotle, in his De Sensu.[2]

Alhazen (965c. 1040) carried out many investigations and experiments on visual perception, extended the work of Ptolemy on binocular vision, and commented on the anatomical works of Galen.[3][4]

Continued here:
Visual perception - Wikipedia, the free encyclopedia

TABLE OF CONTENTS Aug 2012 By: Blake Nicolucci, BSc, DDS2012-08-01

Ive been wondering what could possibly become the next evolution in dental implantology. At present, most dental implant companies have been flogging the same materials, shapes, and coatings and then simply putting their name on the new product. The growth in the number of implant companies in recent years has created greater competition and lower market prices for the dentist. But to excel it is not enough to just be competitive in the market. There must be more research and innovation for a company to remain viable, desirable and ahead of the curve.

Stem cell research is not a new medical entity by any means. There has been extensive research for many years now in the areas of orthopedics, cardiology, neurology and internal medicine. It has only been recently that the dental field has taken a harder look at stem cells and their use not only in promoting more predictable bone grafting but in the reconstruction of the entire dental follicle. Before this, research on stem cells was being concentrated on the healing of diseased and/or traumatized tissues and organs. More recently, stem cells have been used to grow complete and functional organs such as hearts (in mice) and are now being used in an experimental basis to repair heart muscle in human patients who have had massive heart attacks. They are trying to regenerate the dead portion of the ventricular muscle back from its scar tissue state (a result of blood loss after blockage of the LAD artery) to a healed and normal functioning muscle. This therapy is now in clinical trials in Kentucky and California, but it shouldnt be too long before it is established as a viable medical procedure. Toronto has now started a cardiac stem cell program of its own. In the U.S. studies, stem cells are harvested from the septum of the heart (between the atria) and are therefore already in a cardiac ready mode to reproduce cells. These cells are then injected around the scar tissue in the ventricle in some 12 to 15 circumferential positions. The results have been very promising with some patients reportedly having an increased cardiac ejection fraction of up to 50% so that a person with an ejection fraction of 20% could increase their fraction to 30%.

All of this new medical research has stimulated the dental research community to investigate tooth reproduction from stem cells even further. Replacement of the entire tooth (root, crown, pulp, and periodontal structures) has become the focus of research by some of the more state of the art companies who might be afraid that the standard titanium dental implants will become obsolete in the future. Researchers from the Institute of Biotechnology at the University of Helsinki have had overwhelming success in the process of generating teeth in mammals, and it will only be a short time before this is established in humans (please understand that a short time in research standards can translate into decades for you and I).

The process of producing a tooth is very complex and has many different aspects. As such, there are many different approaches taken by the different researchers and research facilities. Stem cells have been extracted from bone marrow and have been found to have osteogenic precursors. These mesenchymal progenitor cells have the potential to differentiate into multiple tissue types such as bone, cartilage, adipose tissue, connective tissue and skeletal muscle.

The statement control of morphogenesis and cyto-differentiation is a challenge to me is an understatement. I tip my hat to all of the researchers who have taken it upon themselves to investigate the regeneration of teeth in humans. At Columbia University Medical Center, Dr. Jeremy Mao is researching a technique in which growth-factor covered three-dimensional scaffolding is being used to act as a cell-homing device. This mesh shaped tooth is implanted into the host tissue, and within nine weeks, significant growth and maturation has occurred. This has been accomplished outside the body (in a Petri dish) and in vivo. Once formation has been completed outside the body, they are then able to transplant the structure to a specific site in the jaw.

What does this mean to me and my practice today? I hope you realize that this is the future of dental implantology. Onward and upward! Progress! Dental implants have been a major part of my life for over 30 years now. This atypical research and development has intrigued me since its inception, and if you are involved in implant dentistry, then you too should be aware of these facts, since this will impact us all in some way in the future! I hope that during my lifetime I will be a part of this new world of dental implants and be able to use stem cells to replace missing teeth in my patients. This is really an exciting frontier! OH

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Stem Cells and Dental Implants - Oral Health Group

Blindness facts Blindness is strictly defined as the state of being totally sightless in both eyes. A completely blind individual is unable to see at all. The word blindness, however, is commonly used as a relative term to signify visual impairment, or low vision, meaning that even with eyeglasses, contact lenses, medicine or surgery, a person does not see well. Vision impairment can range from mild to severe. Worldwide, between 300 million and 400 million people are visually impaired due to various causes. Of this group, approximately 50 million people are totally blind, unable to see light in either eye. Eighty percent of blindness occurs in people over 50 years old. Common causes of blindness include diabetes, macular degeneration, traumatic injuries, infections, glaucoma, and inability to obtain any glasses. Less common causes of blindness include vitamin A deficiency, retinopathy of prematurity, vascular disease involving the retina or optic nerve including stroke, ocular inflammatory disease, retinitis pigmentosa, primary or secondary malignancies of the eye, congenital abnormalities, hereditary diseases of the eye, and chemical poisoning from toxic agents such as methanol. Temporary blindness differs in causes from permanent blindness. The diagnosis of blindness is made by examination of all parts of the eye by an ophthalmologist. The universal symptom of blindness or visual impairment is difficulty with seeing. People who lose their vision suddenly, rather than over a period of years, are more symptomatic regarding their visual loss. The treatment of blindness depends on the cause of blindness. The prognosis for blindness is dependent on its cause. Legal blindness is defined by lawmakers in nations or states in order to either limit allowable activities, such as driving, of individuals who are "legally blind" or to provide preferential governmental benefits to those people in the form of special educational services, assistance with daily functions or monetary assistance. It is estimated that approximately 700,000 people in the United States meet the legal definition of blindness. In most states in the United States, "legal blindness" is defined as the inability to see at least 20/200 in either eye with best optical correction. Between 80%-90% of the blindness in the world is preventable through a combination of education, access to good medical care, and provision of glasses. Patients who have untreatable blindness require reorganization of their habits and re-education to allow them to do everyday tasks in different ways. In the United States and most other developed nations, financial assistance through various agencies can pay for the training and support necessary to allow a blind person to function. There are countless individuals with blindness, who, despite significant visual handicaps, have had full lives and enriched the lives of those who have had contact with them. What is blindness?

Blindness is defined as the state of being sightless. A blind individual is unable to see. In a strict sense the word "blindness" denotes the inability of a person to distinguish darkness from bright light in either eye. The terms blind and blindness have been modified in our society to include a wide range of visual impairment. Blindness is frequently used today to describe severe visual decline in one or both eyes with maintenance of some residual vision.

Vision impairment, or low vision, means that even with eyeglasses, contact lenses, medicine, or surgery, someone doesn't see well. Vision impairment can range from mild to severe. Worldwide, between 300 million-400 million people are visually impaired due to various causes. Of this group, approximately 50 million people are totally blind. Approximately 80% of blindness occurs in people over 50 years of age.

Medically Reviewed by a Doctor on 2/25/2015

Blindness - Causes Question: Please discuss the cause of blindness in a relative or friend?

Blindness - Diagnosis Question: Discuss the events that led to a diagnosis of blindness.

Blindness - Treatment Question: Please discuss treatments for blindness received by you or someone you know.

Blindness - Legally Blind Question: Please discuss in what ways being "legally blind" has affected your lifestyle.

Medical Author:

Andrew A. Dahl, MD, is a board-certified ophthalmologist. Dr. Dahl's educational background includes a BA with Honors and Distinction from Wesleyan University, Middletown, CT, and an MD from Cornell University, where he was selected for Alpha Omega Alpha, the national medical honor society. He had an internal medical internship at the New York Hospital/Cornell Medical Center.

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Blindness: Get Facts About Causes of Vision Loss

Blindness is a 2008 Canadian film in English. It is an adaptation of the 1995 novel of the same name by Portuguese author Jos Saramago about a society suffering an epidemic of blindness. The film was written by Don McKellar and directed by Fernando Meirelles with Julianne Moore and Mark Ruffalo as the main characters. Saramago originally refused to sell the rights for a film adaptation, but the producers were able to acquire it with the condition that the film would be set in an unnamed and unrecognizable city. Blindness premiered as the opening film at the Cannes Film Festival on May 14, 2008, and the film was released in the United States on October 3, 2008.

In an unnamed city, a young Japanese professional (Yusuke Iseya) is suddenly struck blind for no apparent reason. The Japanese man is approached by a few concerned people, one of whom (Don McKellar) offers to drive him home, and later steals his car. The blinded man describes his sudden affliction: an expanse of dazzling white, as though he is "swimming in milk".

Upon arriving home later that evening and noticing her husband's blindness, the Japanese man's wife (Yoshino Kimura) takes him to a local ophthalmologist (Mark Ruffalo) who, after testing the man's eyes, can identify nothing wrong with his sight and recommends further evaluation at a hospital. Among the doctor's patients are an old man with a black eye-patch (Danny Glover), a woman with dark glasses (Alice Braga), and a young boy (Mitchell Nye).

During a dinner with his wife (Julianne Moore), the doctor discusses the strange case of sudden blindness that hit the Japanese man. Elsewhere in the city, the woman with dark glassesrevealed to be a call-girlbecomes the third victim of the strange blindness after an appointment with a john in a luxury hotel.

The next day, the doctor wakes up to realize that he too has gone blind. In various locations around the city, more citizens are struck blind, causing widespread panic, and the government organizes a quarantine for the blind in a local derelict asylum. When a hazmat crew arrives to pick up the doctor, his wife climbs into the van with him, lying that she has also gone blind in order to accompany him into isolation.

In the asylum, the doctor and his wife are first to arrive and both agree they will keep her sight a secret. Several others arrive: the woman with dark glasses, the Japanese man, the car thief, and the young boy. The doctor's wifewho continues to remain sightedcomes across the old man with the eye-patch, who describes the condition of the world outside. The sudden blindness, known only as the "white sickness", is now international, with hundreds of cases being reported every day. Desperate by this point, the increasingly totalitarian government resorts to increasingly ruthless measures to try to staunch the epidemic, refusing the sick any aid or medicines.

In due course, as more and more blind people are crammed into the fetid prison, overcrowding and total lack of any outside support cause the hygiene and living conditions to degrade horrifically in a short time. Soon, the walls and floors are caked in filth and human feces. Anxiety over the availability of food, caused by irregular deliveries, undermines the morale inside. The lack of organization prevents the blind internees from fairly distributing food among each other. The soldiers who guard the asylum become increasingly hostile.

Living conditions degenerate even further when an armed clique of men, led by an ex-barman who declares himself the king of ward 3 (Gael Garca Bernal), gains control over the sparse deliveries of food. The MRE rations are distributed only in exchange for valuables, and then for the women of the other wards. Faced with starvation, the doctor's wife snaps and murders the king of ward 3. His death initiates a chaotic war between the wards, which culminates with the asylum being burned down and most of the inmates die in the fire. Only then do the few survivors discover that the military have abandoned their posts and they are free to venture into the city.

Society has fallen as the entire population is blind amid a city devastated and overrun with filth and dead bodies. The doctor's wife leads her husband and several others in search of food and shelter. The doctor and his wife arrive in a supermarket filled with stumbling blind people, and they find food in a basement storeroom. As she prepares to leave and meet her husband outside, she is attacked by the starving people who smell the food she is carrying. Her husband, now used to his blindness, saves her and they manage to return to their friends.

The doctor and his wife with their new "family" eventually make their way back to the house of the doctor, where they establish a permanent home. Just as suddenly as his sight had been lost, the Japanese man recovers his sight one morning. As the friends all celebrate, the doctor's wife stands out on the porch, staring up into a white overcast sky and for a moment appears to be going blind herself until the video camera shifts downwards, revealing that she sees the cityscape before her.

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Blindness (film) - Wikipedia, the free encyclopedia

Have you ever put on a blindfold and pretended that you couldn't see? You probably bumped into things and got confused about which way you were going. But if you had to, you could get adjusted and learn to live without your sight.

Lots of people have done just that. They have found ways to learn, play, and work, even though they have trouble seeing or can't see at all.

Your eyes and your brain work together to see. The eye is made up of many different parts, including the cornea, iris, lens, and retina. These parts all work together to focus on light and images. Your eyes then use special nerves to send what you see to your brain, so your brain can process and recognize what you're seeing. In eyes that work correctly, this process happens almost instantly.

When this doesn't work the way it should, a person may be visually impaired, or blind. The problem may affect one eye or both eyes.

When you think of being blind, you might imagine total darkness. But most people who are blind can still see a little light or shadows. They just can't see things clearly. People who have some sight, but still need a lot of help, are sometimes called "legally blind."

Vision problems can develop before a baby is born. Sometimes, parts of the eyes don't form the way they should. A kid's eyes might look fine, but the brain has trouble processing the information they send. The optic nerve sends pictures to the brain, so if the nerve doesn't form correctly, the baby's brain won't receive the messages needed for sight.

Blindness can be genetic (or inherited), which means that this problem gets passed down to a kid from parents through genes.

Blindness also can be caused by an accident, if something hurts the eye. That's why it's so important to protect your eyes when you play certain sports, such as hockey.

Some illnesses, such as diabetes, can damage a person's vision over time. Other eye diseases, such as cataracts (say: KAH-tuh-rakts), can cause vision problems or blindness, but they usually affect older people.

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Blindness - KidsHealth

Pamela Peters, from Biotechnology: A Guide To Genetic Engineering. Wm. C. Brown Publishers, Inc., 1993.

Biotechnology in one form or another has flourished since prehistoric times. When the first human beings realized that they could plant their own crops and breed their own animals, they learned to use biotechnology. The discovery that fruit juices fermented into wine, or that milk could be converted into cheese or yogurt, or that beer could be made by fermenting solutions of malt and hops began the study of biotechnology. When the first bakers found that they could make a soft, spongy bread rather than a firm, thin cracker, they were acting as fledgling biotechnologists. The first animal breeders, realizing that different physical traits could be either magnified or lost by mating appropriate pairs of animals, engaged in the manipulations of biotechnology.

What then is biotechnology? The term brings to mind many different things. Some think of developing new types of animals. Others dream of almost unlimited sources of human therapeutic drugs. Still others envision the possibility of growing crops that are more nutritious and naturally pest-resistant to feed a rapidly growing world population. This question elicits almost as many first-thought responses as there are people to whom the question can be posed.

In its purest form, the term "biotechnology" refers to the use of living organisms or their products to modify human health and the human environment. Prehistoric biotechnologists did this as they used yeast cells to raise bread dough and to ferment alcoholic beverages, and bacterial cells to make cheeses and yogurts and as they bred their strong, productive animals to make even stronger and more productive offspring.

Throughout human history, we have learned a great deal about the different organisms that our ancestors used so effectively. The marked increase in our understanding of these organisms and their cell products gains us the ability to control the many functions of various cells and organisms. Using the techniques of gene splicing and recombinant DNA technology, we can now actually combine the genetic elements of two or more living cells. Functioning lengths of DNA can be taken from one organism and placed into the cells of another organism. As a result, for example, we can cause bacterial cells to produce human molecules. Cows can produce more milk for the same amount of feed. And we can synthesize therapeutic molecules that have never before existed.

Go to next story: Where Did Biotechnology Begin?

Return to About Biotech directory

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What is Biotechnology ? - Access Excellence

Arthritis (from Greek arthro-, joint + -itis, inflammation; plural: arthritides) is a form of joint disorder that involves inflammation of one or more joints.[1][2] There are over 100 different forms of arthritis.[3][4] The most common form of arthritis is osteoarthritis (degenerative joint disease), a result of trauma to the joint, infection of the joint, or age. Other arthritis forms are rheumatoid arthritis, psoriatic arthritis, and related autoimmune diseases. Septic arthritis is caused by joint infection.

The major complaint by individuals who have arthritis is joint pain. Pain is often a constant and may be localized to the joint affected. The pain from arthritis is due to inflammation that occurs around the joint, damage to the joint from disease, daily wear and tear of joint, muscle strains caused by forceful movements against stiff painful joints and fatigue.

There are several diseases where joint pain is primary, and is considered the main feature. Generally when a person has "arthritis" it means that they have one of these diseases, which include:

Joint pain can also be a symptom of other diseases. In this case, the arthritis is considered to be secondary to the main disease; these include:

An undifferentiated arthritis is an arthritis that does not fit into well-known clinical disease categories, possibly being an early stage of a definite rheumatic disease.[5]

Pain, which can vary in severity, is a common symptom in virtually all types of arthritis. Other symptoms include swelling, joint stiffness and aching around the joint(s). Arthritic disorders like lupus and rheumatoid arthritis can affect other organs in the body, leading to a variety of symptoms.[7] Symptoms may include:

It is common in advanced arthritis for significant secondary changes to occur. For example, arthritic symptoms might make it difficult for a person to move around and/or exercise, which can lead to secondary effects, such as:

These changes, in addition to the primary symptoms, can have a huge impact on quality of life.

Arthritis is the most common cause of disability in the USA. More than 20 million individuals with arthritis have severe limitations in function on a daily basis.[8]Absenteeism and frequent visits to the physician are common in individuals who have arthritis. Arthritis can make it very difficult for individuals to be physically active and some become home bound.

It is estimated that the total cost of arthritis cases is close to $100 billion of which almost 50% is from lost earnings. Each year, arthritis results in nearly 1 million hospitalizations and close to 45 million outpatient visits to health care centers.[9]

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Arthritis - Wikipedia, the free encyclopedia

Stem cell facts Stem cells are primitive cells that have the potential to differentiate, or develop into, a variety of specific cell types. There are different types of stem cells based upon their origin and ability to differentiate. Bone marrow transplantation is an example of a stem cell therapy that is in widespread use. Research is underway to determine whether stem cell therapy may be useful in treating a wide variety of conditions, including diabetes, heart disease, Parkinson's disease, and spinal cord injury. What are stem cells?

Stem cells are cells that have the potential to develop into many different or specialized cell types. Stem cells can be thought of as primitive, "unspecialized" cells that are able to divide and become specialized cells of the body such as liver cells, muscle cells, blood cells, and other cells with specific functions. Stem cells are referred to as "undifferentiated" cells because they have not yet committed to a developmental path that will form a specific tissue or organ. The process of changing into a specific cell type is known as differentiation. In some areas of the body, stem cells divide regularly to renew and repair the existing tissue. The bone marrow and gastrointestinal tract are examples areas in which stem cells function to renew and repair tissue.

The best and most readily understood example of a stem cell in humans is that of the fertilized egg, or zygote. A zygote is a single cell that is formed by the union of a sperm and ovum. The sperm and the ovum each carry half of the genetic material required to form a new individual. Once that single cell or zygote starts dividing, it is known as an embryo. One cell becomes two, two become four, four become eight, eight to sixteen, and so on; doubling rapidly until it ultimately creates the entire sophisticated organism. That organism, a person, is an immensely complicated structure consisting of many, many, billions of cells with functions as diverse as those of your eyes, your heart, your immune system, the color of your skin, your brain, etc. All of the specialized cells that make up these body systems are descendants of the original zygote, a stem cell with the potential to ultimately develop into all kinds of body cells. The cells of a zygote are totipotent, meaning that they have the capacity to develop into any type of cell in the body.

The process by which stem cells commit to become differentiated, or specialized, cells is complex and involves the regulation of gene expression. Research is ongoing to further understand the molecular events and controls necessary for stem cells to become specialized cell types.

Medically Reviewed by a Doctor on 1/23/2014

Stem Cells - Experience Question: Please describe your experience with stem cells.

Stem Cells - Umbilical Cord Question: Have you had your child's umbilical cord blood banked? Please share your experience.

Stem Cells - Available Therapies Question: Did you or someone you know have stem cell therapy? Please discuss your experience.

Medical Author:

Melissa Conrad Stppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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Stem Cells: Get Facts on Uses, Types, and Therapies