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Aconitine
Aconitine is an alkaloid toxin produced by various plant species belonging to the genus ''Aconitum'' (family Ranunculaceae), known also commonly by the names wolfsbane and monkshood. Monkshood is notorious for its toxic properties. Aconitine is also present in Yunnan Baiyao, a proprietary traditional Chinese medicine. Uses Aconitine was previously used as an antipyretic and analgesic and still has some limited application in herbal medicine, although the narrow therapeutic index makes calculating appropriate dosage difficult. Structure and reactivity Biologically active isolates from ''Aconitum'' and '' Delphinium'' plants are classified as norditerpenoid alkaloids, which are further subdivided based on the presence or absence of the C18 carbon. Aconitine is a C19-norditerpenoid, based on its presence of this C18 carbon. It is barely soluble in water, but very soluble in organic solvents such as chloroform or diethyl ether. Aconitine is also soluble in mixtures of alcohol a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aconitum
''Aconitum'' (), also known as aconite, monkshood, wolf's-bane, leopard's bane, mousebane, women's bane, devil's helmet, queen of poisons, or blue rocket, is a genus of over 250 species of flowering plants belonging to the family Ranunculaceae. These herbaceous perennial plants are chiefly native to the mountainous parts of the Northern Hemisphere in North America, Europe, and Asia; growing in the moisture-retentive but well-draining soils of mountain meadows. Most ''Aconitum'' species are extremely poisonous and must be handled very carefully. Several ''Aconitum'' hybrids, such as the Arendsii form of '' Aconitum carmichaelii'', have won gardening awards—such as the Royal Horticultural Society's Award of Garden Merit. Some are used by florists. Etymology The name ''aconitum'' comes from the Greek word , which may derive from the Greek ''akon'' for dart or javelin, the tips of which were poisoned with the substance, or from ''akonae'', because of the rocky ground on which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monkshood
''Aconitum'' (), also known as aconite, monkshood, wolf's-bane, leopard's bane, mousebane, women's bane, devil's helmet, queen of poisons, or blue rocket, is a genus of over 250 species of flowering plants belonging to the family Ranunculaceae. These herbaceous perennial plants are chiefly native to the mountainous parts of the Northern Hemisphere in North America, Europe, and Asia; growing in the moisture-retentive but well-draining soils of mountain meadows. Most ''Aconitum'' species are extremely poisonous and must be handled very carefully. Several ''Aconitum'' hybrids, such as the Arendsii form of ''Aconitum carmichaelii'', have won gardening awards—such as the Royal Horticultural Society's Award of Garden Merit. Some are used by florists. Etymology The name ''aconitum'' comes from the Greek word , which may derive from the Greek ''akon'' for dart or javelin, the tips of which were poisoned with the substance, or from ''akonae'', because of the rocky ground on which t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alkaloid
Alkaloids are a class of basic, naturally occurring organic compounds that contain at least one nitrogen atom. This group also includes some related compounds with neutral and even weakly acidic properties. Some synthetic compounds of similar structure may also be termed alkaloids. In addition to carbon, hydrogen and nitrogen, alkaloids may also contain oxygen, sulfur and, more rarely, other elements such as chlorine, bromine, and phosphorus.Chemical Encyclopedia: alkaloids xumuk.ru Alkaloids are produced by a large variety of organisms including bacteria, fungi, [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetylcholine
Acetylcholine (ACh) is an organic chemical that functions in the brain and body of many types of animals (including humans) as a neurotransmitter. Its name is derived from its chemical structure: it is an ester of acetic acid and choline. Parts in the body that use or are affected by acetylcholine are referred to as cholinergic. Substances that increase or decrease the overall activity of the cholinergic system are called cholinergics and anticholinergics, respectively. Acetylcholine is the neurotransmitter used at the neuromuscular junction—in other words, it is the chemical that motor neurons of the nervous system release in order to activate muscles. This property means that drugs that affect cholinergic systems can have very dangerous effects ranging from paralysis to convulsions. Acetylcholine is also a neurotransmitter in the autonomic nervous system, both as an internal transmitter for the sympathetic nervous system and as the final product released by the par ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Synapse
Chemical synapses are biological junctions through which neurons' signals can be sent to each other and to non-neuronal cells such as those in muscles or glands. Chemical synapses allow neurons to form circuits within the central nervous system. They are crucial to the biological computations that underlie perception and thought. They allow the nervous system to connect to and control other systems of the body. At a chemical synapse, one neuron releases neurotransmitter molecules into a small space (the synaptic cleft) that is adjacent to another neuron. The neurotransmitters are contained within small sacs called synaptic vesicles, and are released into the synaptic cleft by exocytosis. These molecules then bind to neurotransmitter receptors on the postsynaptic cell. Finally, the neurotransmitters are cleared from the synapse through one of several potential mechanisms including enzymatic degradation or re-uptake by specific transporters either on the presynaptic cell or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetylcholine Receptor
An acetylcholine receptor (abbreviated AChR) is an integral membrane protein that responds to the binding of acetylcholine, a neurotransmitter. Classification Like other transmembrane receptors, acetylcholine receptors are classified according to their "pharmacology," or according to their relative affinities and sensitivities to different molecules. Although all acetylcholine receptors, by definition, respond to acetylcholine, they respond to other molecules as well. *Nicotinic acetylcholine receptors (''nAChR'', also known as "ionotropic" acetylcholine receptors) are particularly responsive to nicotine. The nicotine ACh receptor is also a Na+, K+ and Ca2+ ion channel. *Muscarinic acetylcholine receptors (''mAChR'', also known as "metabotropic" acetylcholine receptors) are particularly responsive to muscarine. Nicotinic and muscarinic are two main kinds of "cholinergic" receptors. Receptor types Molecular biology has shown that the nicotinic and muscarinic receptors belong ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cell Membrane
The cell membrane (also known as the plasma membrane (PM) or cytoplasmic membrane, and historically referred to as the plasmalemma) is a biological membrane that separates and protects the interior of all cells from the outside environment (the extracellular space). The cell membrane consists of a lipid bilayer, made up of two layers of phospholipids with cholesterols (a lipid component) interspersed between them, maintaining appropriate membrane fluidity at various temperatures. The membrane also contains membrane proteins, including integral proteins that span the membrane and serve as membrane transporters, and peripheral proteins that loosely attach to the outer (peripheral) side of the cell membrane, acting as enzymes to facilitate interaction with the cell's environment. Glycolipids embedded in the outer lipid layer serve a similar purpose. The cell membrane controls the movement of substances in and out of cells and organelles, being selectively permeable to i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Depolarization
In biology, depolarization or hypopolarization is a change within a cell, during which the cell undergoes a shift in electric charge distribution, resulting in less negative charge inside the cell compared to the outside. Depolarization is essential to the function of many cells, communication between cells, and the overall physiology of an organism. Most cells in higher organisms maintain an internal environment that is negatively charged relative to the cell's exterior. This difference in charge is called the cell's membrane potential. In the process of depolarization, the negative internal charge of the cell temporarily becomes more positive (less negative). This shift from a negative to a more positive membrane potential occurs during several processes, including an action potential. During an action potential, the depolarization is so large that the potential difference across the cell membrane briefly reverses polarity, with the inside of the cell becoming positively char ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neuron
A neuron, neurone, or nerve cell is an electrically excitable cell that communicates with other cells via specialized connections called synapses. The neuron is the main component of nervous tissue in all animals except sponges and placozoa. Non-animals like plants and fungi do not have nerve cells. Neurons are typically classified into three types based on their function. Sensory neurons respond to stimuli such as touch, sound, or light that affect the cells of the sensory organs, and they send signals to the spinal cord or brain. Motor neurons receive signals from the brain and spinal cord to control everything from muscle contractions to glandular output. Interneurons connect neurons to other neurons within the same region of the brain or spinal cord. When multiple neurons are connected together, they form what is called a neural circuit. A typical neuron consists of a cell body (soma), dendrites, and a single axon. The soma is a compact structure, and the axon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Channel
Sodium channels are integral membrane proteins that form ion channels, conducting sodium ions (Na+) through a cell's membrane. They belong to the superfamily of cation channels and can be classified according to the trigger that opens the channel for such ions, i.e. either a voltage-change ("voltage-gated", "voltage-sensitive", or "voltage-dependent" sodium channel; also called "VGSCs" or "Nav channel") or a binding of a substance (a ligand) to the channel ( ligand-gated sodium channels). In excitable cells such as neurons, myocytes, and certain types of glia, sodium channels are responsible for the rising phase of action potentials. These channels go through three different states called resting, active and inactive states. Even though the resting and inactive states would not allow the ions to flow through the channels the difference exists with respect to their structural conformation. Selectivity Sodium channels are highly selective for the transport of ions across ce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyrolysis
The pyrolysis (or devolatilization) process is the thermal decomposition of materials at elevated temperatures, often in an inert atmosphere. It involves a change of chemical composition. The word is coined from the Greek-derived elements ''pyro'' "fire", "heat", "fever" and '' lysis'' "separating". Pyrolysis is most commonly used in the treatment of organic materials. It is one of the processes involved in charring wood.''Burning of wood'' , InnoFireWood's website. Accessed on 2010-02-06. In general, pyrolysis of organic substances produces volatile products and leaves , a carbon-rich solid residue. Extreme pyrolysis, which leaves mostly |
Methanol
Methanol (also called methyl alcohol and wood spirit, amongst other names) is an organic chemical and the simplest aliphatic alcohol, with the formula C H3 O H (a methyl group linked to a hydroxyl group, often abbreviated as MeOH). It is a light, volatile, colourless, flammable liquid with a distinctive alcoholic odour similar to that of ethanol (potable alcohol). A polar solvent, methanol acquired the name wood alcohol because it was once produced chiefly by the destructive distillation of wood. Today, methanol is mainly produced industrially by hydrogenation of carbon monoxide. Methanol consists of a methyl group linked to a polar hydroxyl group. With more than 20 million tons produced annually, it is used as a precursor to other commodity chemicals, including formaldehyde, acetic acid, methyl tert-butyl ether, methyl benzoate, anisole, peroxyacids, as well as a host of more specialised chemicals. Occurrence Small amounts of methanol are present in normal, healthy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
