Flaccid
Flaccid paralysis is a neurological condition characterized by weakness or paralysis and reduced muscle tone without other obvious cause (e.g., trauma). This abnormal condition may be caused by disease or by trauma affecting the nerves associated with the involved muscles. For example, if the somatic nerves to a skeletal muscle are severed, then the muscle will exhibit flaccid paralysis. When muscles enter this state, they become limp and cannot contract. This condition can become fatal if it affects the respiratory muscles, posing the threat of suffocation. It also occurs in the spinal shock stage in complete transection of the spinal cord occurring in injuries such as gunshot wounds.Saladin, Kenneth S. Anatomy & Physiology: The Unity of Form and Function. McGraw-Hill. 6th Edition. 2012. Causes Polio and other viruses The term ''acute flaccid paralysis'' (AFP) is often used to describe an instance with a sudden onset, as might be found with polio. AFP is the most c ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Polio
Poliomyelitis ( ), commonly shortened to polio, is an infectious disease caused by the poliovirus. Approximately 75% of cases are asymptomatic; mild symptoms which can occur include sore throat and fever; in a proportion of cases more severe symptoms develop such as headache, neck stiffness, and paresthesia. These symptoms usually pass within one or two weeks. A less common symptom is permanent Flaccid paralysis, paralysis, and possible death in extreme cases.. Years after recovery, post-polio syndrome may occur, with a slow development of muscle weakness similar to what the person had during the initial infection. Polio occurs naturally only in humans. It is highly infectious, and is spread from person to person either through fecal–oral route, fecal–oral transmission (e.g. poor hygiene, or by ingestion of food or water contaminated by human feces), or via the oral–oral route. Those who are infected may spread the disease for up to six weeks even if no symptoms are pre ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Botulism
Botulism is a rare and potentially fatal illness caused by botulinum toxin, which is produced by the bacterium ''Clostridium botulinum''. The disease begins with weakness, blurred vision, Fatigue (medical), feeling tired, and trouble speaking. This may then be followed by weakness of the arms, chest muscles, and legs. Vomiting, swelling of the abdomen, and diarrhea may also occur. The disease does not usually affect consciousness or cause a fever. Botulism can occur in several ways. The bacterial spores which cause it are common in both soil and water and are very resistant. They produce the botulinum toxin when exposed to low oxygen levels and certain temperatures. Foodborne botulism happens when food containing the toxin is eaten. Infant botulism instead happens when the bacterium develops in the intestines and releases the toxin. This typically only occurs in children less than one year old, as protective mechanisms against development of the bacterium develop after that age ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Enterovirus
''Enterovirus'' is a genus of positive-sense single-stranded RNA viruses associated with several human and mammalian diseases. Enteroviruses are named by their transmission-route through the intestine ('enteric' meaning intestinal). Serologic studies have distinguished 71 human enterovirus serotypes on the basis of antibody neutralization tests. Additional antigenic variants have been defined within several of the serotypes on the basis of reduced or nonreciprocal cross-neutralization between variant strains. On the basis of their pathogenesis in humans and animals, the enteroviruses were originally classified into four groups, polioviruses, Coxsackie A viruses (CA), Coxsackie B viruses (CB), and echoviruses, but it was quickly realized that there were significant overlaps in the biological properties of viruses in the different groups. Enteroviruses isolated more recently are named with a system of consecutive numbers: EV-D68, EV-B69, EV-D70, EV-A71, etc., where genotyping ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Muscle Tone
In physiology, medicine, and anatomy, muscle tone (residual muscle tension or tonus) is the continuous and passive partial contraction of the muscles, or the muscle's resistance to passive stretch during resting state.O’Sullivan, S. B. (2007). Examination of motor function: Motor control and motor learning. In S. B. O’Sullivan, & T. J. Schmitz (Eds), Physical rehabilitation (5th ed.) (pp. 233-234). Philadelphia, Pennsylvania: F. A. Davis Company. It helps to maintain posture and declines during REM sleep. Muscle tone is regulated by the activity of the motor neurons and can be affected by various factors, including age, disease, and nerve damage. Purpose If a sudden pull or stretch occurs, the body responds by automatically increasing the muscle's tension, a reflex which helps guard against danger as well as helping maintain balance. Such near-continuous innervation can be thought of as a "default" or "steady state" condition for muscles. Both the extensor and flexo ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Lower Motor Neuron Lesion
A lower motor neuron lesion is a lesion which affects nerve fibers traveling from the lower motor neuron(s) in the anterior horn/anterior grey column of the spinal cord, or in the motor nuclei of the cranial nerves, to the relevant muscle(s). One major characteristic used to identify a lower motor neuron lesion is flaccid paralysis – paralysis accompanied by loss of muscle tone. This is in contrast to an upper motor neuron lesion, which often presents with spastic paralysis – paralysis accompanied by severe hypertonia. Signs and symptoms * Muscle paresis or paralysis * Fibrillations * Fasciculations – caused by increased receptor concentration on muscles to compensate for lack of innervation. * Hypotonia or atonia – Tone is not velocity dependent. * Hyporeflexia - Along with deep reflexes even cutaneous reflexes are also decreased or absent. * Strength – weakness is limited to segmental or focal pattern, Root innervated pattern The extensor plantar reflex ( Babin ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Clostridium Botulinum
''Clostridium botulinum'' is a Gram-positive bacteria, gram-positive, Bacillus (shape), rod-shaped, Anaerobic organism, anaerobic, endospore, spore-forming, Motility, motile bacterium with the ability to produce botulinum toxin, which is a neurotoxin. ''C. botulinum'' is a diverse group of pathogenic bacteria. Initially, they were grouped together by their ability to produce botulinum toxin and are now known as four distinct groups, ''C. botulinum'' groups I–IV. Along with some strains of ''Clostridium butyricum'' and ''Clostridium baratii'', these bacteria all produce the toxin. Botulinum toxin can cause botulism, a severe Flaccid paralysis, flaccid paralytic disease in humans and other animals, and is the most potent toxin known to science, natural or synthetic, with a lethal dose of 1.3–2.1 ng/kg in humans.(2010). Chapter 19. ''Clostridium'', ''Peptostreptococcus'', ''Bacteroides'', and Other Anaerobes. In Ryan K.J., Ray C (Eds), ''Sherris Medical Microbiology'', 5th ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Endospore
An endospore is a dormant, tough, and non-reproductive structure produced by some bacteria in the phylum Bacillota. The name "endospore" is suggestive of a spore or seed-like form (''endo'' means 'within'), but it is not a true spore (i.e., not an offspring). It is a stripped-down, dormant form to which the bacterium can reduce itself. Endospore formation is usually triggered by a lack of nutrients, and usually occurs in Gram-positive bacteria. In endospore formation, the bacterium divides within its cell wall, and one side then engulfs the other. Endospores enable bacteria to lie dormant for extended periods, even centuries. There are many reports of spores remaining viable over 10,000 years, and revival of spores millions of years old has been claimed. There is one report of viable spores of '' Bacillus marismortui'' in salt crystals approximately 25 million years old. When the environment becomes more favorable, the endospore can reactivate itself into a vegetative state. Mos ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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In Vivo
Studies that are ''in vivo'' (Latin for "within the living"; often not italicized in English) are those in which the effects of various biological entities are tested on whole, living organisms or cells, usually animals, including humans, and plants, as opposed to a tissue extract or dead organism. Examples of investigations ''in vivo'' include: the pathogenesis of disease by comparing the effects of bacterial infection with the effects of purified bacterial toxins; the development of non-antibiotics, antiviral drugs, and new drugs generally; and new surgical procedures. Consequently, animal testing and clinical trials are major elements of ''in vivo'' research. ''In vivo'' testing is often employed over ''in vitro'' because it is better suited for observing the overall effects of an experiment on a living subject. In drug discovery, for example, verification of efficacy ''in vivo'' is crucial, because ''in vitro'' assays can sometimes yield misleading results with drug c ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Acetylcholine
Acetylcholine (ACh) is an organic compound 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. 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 both the sympathetic nervous system, sympathetic and the parasympathetic nervous system, and as the final product released by the parasympathetic nervous system. Acetylcholine is the primary neurotransmitter of the parasympathet ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Weakness
Weakness is a symptom of many different medical conditions. The causes are many and can be divided into conditions that have true or perceived muscle weakness. True muscle weakness is a primary symptom of a variety of skeletal muscle diseases, including muscular dystrophy and inflammatory myopathy. It occurs in neuromuscular junction disorders, such as myasthenia gravis. Pathophysiology Muscle cells work by detecting a flow of electrical impulses from the brain, which signals them to contract through the release of calcium by the sarcoplasmic reticulum. Fatigue (reduced ability to generate force) may occur due to the nerve, or within the muscle cells themselves. New research from scientists at Columbia University suggests that muscle fatigue is caused by calcium leaking out of the muscle cell. This makes less calcium available for the muscle cell. In addition, the Columbia researchers propose that an enzyme activated by this released calcium eats away at muscle fibers. Su ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Neurotoxin
Neurotoxins are toxins that are destructive to nervous tissue, nerve tissue (causing neurotoxicity). Neurotoxins are an extensive class of exogenous chemical neurological insult (medical), insultsSpencer 2000 that can adversely affect function in both developing and mature nervous tissue.Olney 2002 The term can also be used to classify endogenous compounds, which, when abnormally contacted, can prove neurologically toxic. Though neurotoxins are often neurologically destructive, their ability to specifically target neural components is important in the study of nervous systems. Common examples of neurotoxins include lead, ethanol (drinking alcohol), glutamate,Choi 1987 nitric oxide, botulinum toxin (e.g. Botox), tetanus toxin,Simpson 1986 and tetrodotoxin. Some substances such as nitric oxide and glutamate are in fact essential for proper function of the body and only exert neurotoxic effects at excessive concentrations. Neurotoxins inhibit neuron control over ion concentrations ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Curare
Curare ( or ; or ) is a common name for various alkaloid arrow poisons originating from plant extracts. Used as a paralyzing agent by indigenous peoples in Central and South America for hunting and for therapeutic purposes, curare only becomes active when it contaminates a wound or is introduced directly to the bloodstream; it is not active when ingested orally. Curare is prepared by boiling the bark of one of the dozens of plant sources, leaving a dark, heavy paste that can be applied to arrow or dart heads. These poisons cause weakness of the skeletal muscles and, when administered in a sufficient dose, eventual death by asphyxiation due to paralysis of the diaphragm. In medicine, curare has been used as a treatment for tetanus and strychnine poisoning and as a paralyzing agent for surgical procedures. History The word 'curare' is derived from , from the Carib language of the Macusi of Guyana. It has its origins in the Carib phrase "mawa cure" meaning of th ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |