Chlorotoxin
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Chlorotoxin
Chlorotoxin is a 36-amino acid peptide found in the venom of the deathstalker scorpion (''Leiurus quinquestriatus'') which blocks small-conductance chloride channels. The fact that chlorotoxin binds preferentially to glioma cells has allowed the development of methods for the treatment and diagnosis of several types of cancer. Sources Chlorotoxin can be purified from crude leiurus, which belongs to the scorpion toxin protein superfamily. Chemistry Chlorotoxin is a small toxin and at pH 7 is highly positively charged. It is a peptide consisting of 36 amino acids, with 8 cysteines forming 4 disulfide bonds. Chlorotoxin has a considerable sequence homology to the class of small insectotoxins. Target Chlorotoxin is the first reported high-affinity peptide ligand for Cl− channels and it blocks small conductance chloride channels. Each chloride channel can be closed by only one ligand molecule. Using a recombinant chlorotoxin it was demonstrated that chlorotoxin specifical ...
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Scorpion Toxins
Scorpions are predatory arachnids of the order Scorpiones. They have eight legs, and are easily recognized by a pair of grasping pincers and a narrow, segmented tail, often carried in a characteristic forward curve over the back and always ending with a stinger. The evolutionary history of scorpions goes back 435 million years. They mainly live in deserts but have adapted to a wide range of environmental conditions, and can be found on all continents except Antarctica. There are over 2,500 described species, with 22 extant (living) families recognized to date. Their taxonomy is being revised to account for 21st-century genomic studies. Scorpions primarily prey on insects and other invertebrates, but some species hunt vertebrates. They use their pincers to restrain and kill prey, or to prevent their own predation. The venomous sting is used for offense and defense. During courtship, the male and female grasp each other's pincers and dance while he tries to move her onto his sp ...
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Glioma
A glioma is a type of tumor that starts in the glial cells of the brain or the spine. Gliomas comprise about 30 percent of all brain tumors and central nervous system tumours, and 80 percent of all malignant brain tumours. Signs and symptoms Symptoms of gliomas depend on which part of the central nervous system is affected. A brain glioma can cause headaches, vomiting, seizures, and cranial nerve disorders as a result of increased intracranial pressure. A glioma of the optic nerve can cause visual loss. Spinal cord gliomas can cause pain, weakness, or numbness in the extremities. Gliomas do not usually metastasize by the bloodstream, but they can spread via the cerebrospinal fluid and cause "drop metastases" to the spinal cord. Complex visual hallucinations have been described as a symptom of low-grade glioma. A child who has a subacute disorder of the central nervous system that produces cranial nerve abnormalities (especially of cranial nerve VII and the lower bulbar nerv ...
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Amino Acid
Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although hundreds of amino acids exist in nature, by far the most important are the alpha-amino acids, which comprise proteins. Only 22 alpha amino acids appear in the genetic code. Amino acids can be classified according to the locations of the core structural functional groups, as Alpha and beta carbon, alpha- , beta- , gamma- or delta- amino acids; other categories relate to Chemical polarity, polarity, ionization, and side chain group type (aliphatic, Open-chain compound, acyclic, aromatic, containing hydroxyl or sulfur, etc.). In the form of proteins, amino acid '' residues'' form the second-largest component (water being the largest) of human muscles and other tissues. Beyond their role as residues in proteins, amino acids participate in a number of processes such as neurotransmitter transport and biosynthesis. It is thought that they played a key role in enabling life ...
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Fluorescent
Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation. It is a form of luminescence. In most cases, the emitted light has a longer wavelength, and therefore a lower photon energy, than the absorbed radiation. A perceptible example of fluorescence occurs when the absorbed radiation is in the ultraviolet region of the electromagnetic spectrum (invisible to the human eye), while the emitted light is in the visible region; this gives the fluorescent substance a distinct color that can only be seen when the substance has been exposed to UV light. Fluorescent materials cease to glow nearly immediately when the radiation source stops, unlike phosphorescent materials, which continue to emit light for some time after. Fluorescence has many practical applications, including mineralogy, gemology, medicine, chemical sensors (fluorescence spectroscopy), fluorescent labelling, dyes, biological detectors, cosmic-ray detection, vacuu ...
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Experimental Cancer Drugs
An experiment is a procedure carried out to support or refute a hypothesis, or determine the efficacy or likelihood of something previously untried. Experiments provide insight into cause-and-effect by demonstrating what outcome occurs when a particular factor is manipulated. Experiments vary greatly in goal and scale but always rely on repeatable procedure and logical analysis of the results. There also exist natural experimental studies. A child may carry out basic experiments to understand how things fall to the ground, while teams of scientists may take years of systematic investigation to advance their understanding of a phenomenon. Experiments and other types of hands-on activities are very important to student learning in the science classroom. Experiments can raise test scores and help a student become more engaged and interested in the material they are learning, especially when used over time. Experiments can vary from personal and informal natural comparisons (e. ...
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Gregory House
Gregory House, M.D. is the titular protagonist of the American medical drama series ''House''. Created by David Shore and portrayed by English actor Hugh Laurie, he leads a team of diagnosticians and is the Head of Diagnostic Medicine at the fictional Princeton-Plainsboro Teaching Hospital in Princeton, New Jersey. House's character has been described as a misanthrope, cynic, narcissist, and curmudgeon, the last of which terms was named one of the top television words of 2005 in honor of the character. In the series, the character's unorthodox diagnostic approaches, radical therapeutic motives, and stalwart rationality have resulted in much conflict between him and his colleagues. House is also often portrayed as lacking sympathy for his patients, a practice that allows him time to solve pathological enigmas. The character is partly inspired by Sherlock Holmes. A portion of the show's plot centers on House's habitual use of Vicodin to manage pain stemming from leg infarction ...
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House Md
''House'' (also called ''House, M.D.'') is an American medical drama television series that originally ran on the Fox network for eight seasons, from November 16, 2004, to May 21, 2012. The series' main character is Dr. Gregory House (Hugh Laurie), an unconventional, misanthropic medical genius who, despite his dependence on pain medication, leads a team of diagnosticians at the fictional Princeton–Plainsboro Teaching Hospital (PPTH) in New Jersey. The series' premise originated with Paul Attanasio, while David Shore, who is credited as creator, was primarily responsible for the conception of the title character. The series' executive producers included Shore, Attanasio, Attanasio's business partner Katie Jacobs, and film director Bryan Singer. It was filmed largely in a neighborhood and business district in Los Angeles County's Westside called Century City. The show received high critical acclaim, and was consistently one of the highest rated series in the United States ...
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Both Sides Now (House)
"Both Sides Now" is the twenty-fourth episode and season finale of the fifth season of ''House''. It originally aired on May 11, 2009. Plot House wakes up at his apartment after spending the night with Cuddy. He discovers that she has left her lipstick on his bathroom counter, as well as on his cheek. House pockets the lipstick, and goes to work in a cheerful mood and a remarkable lack of pain. House and the team are intrigued by Scott (Ashton Holmes), a man who has undergone a corpus callosotomy procedure to treat epilepsy. The procedure left him with independently functioning left and right brain hemispheres and two distinct personalities, resulting in loss of conscious control over some of his actions, including those of his left hand, a condition known as alien hand syndrome. As the two sides of Scott's brain struggle for dominance, his warring personalities make it increasingly difficult for the team to figure out what is causing the problem. The team is forced to use some ...
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Infrared
Infrared (IR), sometimes called infrared light, is electromagnetic radiation (EMR) with wavelengths longer than those of visible light. It is therefore invisible to the human eye. IR is generally understood to encompass wavelengths from around 1 millimeter (300 GHz) to the nominal red edge of the visible spectrum, around 700  nanometers (430  THz). Longer IR wavelengths (30 μm-100 μm) are sometimes included as part of the terahertz radiation range. Almost all black-body radiation from objects near room temperature is at infrared wavelengths. As a form of electromagnetic radiation, IR propagates energy and momentum, exerts radiation pressure, and has properties corresponding to both those of a wave and of a particle, the photon. It was long known that fires emit invisible heat; in 1681 the pioneering experimenter Edme Mariotte showed that glass, though transparent to sunlight, obstructed radiant heat. In 1800 the astronomer Sir William Herschel discovered ...
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Fred Hutchinson Cancer Research Center
The Fred Hutchinson Cancer Center, formerly known as the Fred Hutchinson Cancer Research Center and also known as Fred Hutch or The Hutch, is a cancer research institute established in 1975 in Seattle, Washington. History The center grew out of the Pacific Northwest Research Foundation, founded in 1956 by William B. Hutchinson (1909–1997). The Foundation was dedicated to the study of heart surgery, cancer, and diseases of the endocrine system. Hutchinson's younger brother Fred (1919–1964) was a major league pitcher and manager who died of lung cancer at age 45. The next year, William Hutchinson established the Fred Hutchinson Cancer Research Center as a division of the Pacific Northwest Research Foundation.Louis Fiset, December 30, 2004 for HistoryLink: The Free, Online Encyclopedia of Washington State HistorHutchinson, Dr. William B. (1909-1997)/ref> In 1972, with the help of Senator Warren G. Magnuson, PNRF received federal funding under the National Cancer Act of 19 ...
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Cyanine
Cyanines, also referred to as tetramethylindo(di)-carbocyanines are a synthetic dye family belonging to the polymethine group. Although the name derives etymologically from terms for shades of blue, the cyanine family covers the electromagnetic spectrum from near IR to UV. Chemically, cyanines are a conjugated system between two nitrogen atoms; in each resonance structure, exactly one nitrogen atom is oxidized to an iminium. Typically, they form part of a nitrogenous heterocyclic system. The main application for cyanine dyes is in biological labeling. Nevertheless, there is a wide literature on both their synthesis and uses, and cyanines are common in some CD and DVD media. Structure Cyanines have been classified in many ways: * ''Streptocyanines'' or ''open chain cyanines'': : R2N+=CH H=CH'n''-NR2 (I) * ''Hemicyanines'': : Aryl=N+=CH H=CH'n''-NR2 (II) * ''Closed chain cyanines'': :Aryl=N+=CH H=CH'n''-N=Aryl (III) Additionally, these classes are recognized: * ...
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