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Methyl Cobalamin
Methylcobalamin (mecobalamin, MeCbl, or MeB) is a cobalamin, a form of vitamin B. It differs from cyanocobalamin in that the cyano group at the cobalt is replaced with a methyl group. Methylcobalamin features an octahedral cobalt(III) centre and can be obtained as bright red crystals. From the perspective of coordination chemistry, methylcobalamin is notable as a rare example of a compound that contains metal–alkyl bonds. Nickel–methyl intermediates have been proposed for the final step of methanogenesis. __TOC__ Production Methylcobalamin can be produced in the laboratory by reducing cyanocobalamin with sodium borohydride in alkaline solution, followed by the addition of methyl iodide. Functions This vitamer, along with adenosylcobalamin, is one of two active coenzymes used by vitamin B-dependent enzymes and is the specific vitamin B form used by 5-methyltetrahydrofolate-homocysteine methyltransferase (MTR), also known as methionine synthase. Methylcobalamin partici ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oral Administration
Oral administration is a route of administration whereby a substance is taken through the Human mouth, mouth, swallowed, and then processed via the digestive system. This is a common route of administration for many medications. Oral administration can be easier and less painful than other routes of administration, such as Injection (medicine), injection. However, the onset of action is relatively low, and the effectiveness is reduced if it is not absorbed properly in the digestive system, or if it is broken down by digestive enzymes before it can reach the bloodstream. Some medications may cause gastrointestinal side effects, such as nausea or vomiting, when taken orally. Oral administration can also only be applied to conscious patients, and patients able to swallow. Terminology ''Per os'' (; ''P.O.'') is an adverbial phrase meaning literally from Latin "through the mouth" or "by mouth". The expression is used in medicine to describe a treatment that is taken orally (but not ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydroxocobalamin
Hydroxocobalamin, also known as vitamin B12a and hydroxycobalamin, is a vitamin found in food and used as a dietary supplement. As a supplement it is used to treat vitamin B12 deficiency including pernicious anemia. Other uses include treatment for cyanide poisoning, Leber's optic atrophy, and toxic amblyopia. It is given by injection into a muscle or vein, by pill or sublingually. Side effects are generally few. They may include diarrhea, feeling sick, hot flushes, itchiness, low blood potassium, allergic reactions, and high blood pressure. Normal doses are considered safe in pregnancy. No overdosage or toxicity has been reported with this drug. Hydroxocobalamin is the natural form of vitamin B12 and a member of the cobalamin family of compounds. It is found in both raw and cooked beef, together with other cobalamins. Hydroxocobalamin, or another form of vitamin B12, are required for the body to make DNA. Hydroxocobalamin was first isolated in 1949. It is on the World H ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyanocobalamin
Cyanocobalamin is a form of Vitamin B12, vitamin used to treat and prevent vitamin B12 deficiency, vitamin deficiency except in the presence of cyanide toxicity. The deficiency may occur in pernicious anemia, following gastrectomy, surgical removal of the stomach, with fish tapeworm, or due to bowel cancer. It is used by mouth, by injection into a muscle, or as a nasal spray. Cyanocobalamin is generally well tolerated. Minor side effects may include diarrhea, nausea, upset stomach, and itchiness. Serious side effects may include anaphylaxis, and low blood potassium resulting in heart failure. Use is not recommended in those who are allergic to cobalt or have Leber's disease. No overdosage or toxicity has been reported. It is less preferred than hydroxocobalamin for treating vitamin deficiency because it has a slightly lower bioavailability. Some studies have shown it to possess an antihypotensive effect. Vitamin is an essential nutrient meaning that it cannot be made by the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adenosylcobalamin
Adenosylcobalamin (AdoCbl), also known as coenzyme B12, cobamamide, and dibencozide, is one of the biologically active forms of vitamin B12. Adenosylcobalamin participates as a cofactor in radical-mediated 1,2-carbon skeleton rearrangements. These processes require the formation of the deoxyadenosyl radical through homolytic dissociation of the carbon-cobalt bond. This bond is exceptionally weak, with a bond dissociation energy of 31 kcal/mol, which is further lowered in the chemical environment of an enzyme active site. An enzyme that uses adenosylcobalamin as a coenzyme is methylmalonyl-CoA mutase (MCM). Further experimentation has also determined adenosylcobalamin's role in regulating expression of some bacterial genes. By binding to CarH, AdoCbl can modulate carotenoid genes, which confer warm colors onto various plants. Carotenoid transcription is activated by sunlight, due to the response from AdoCbl. There are other photoreceptors across different bacterial communities, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amyotrophic Lateral Sclerosis
Amyotrophic lateral sclerosis (ALS), also known as motor neuron disease (MND) or—in the United States—Lou Gehrig's disease (LGD), is a rare, Terminal illness, terminal neurodegenerative disease, neurodegenerative disorder that results in the progressive loss of both upper and lower motor neurons that normally control Skeletal muscle, voluntary muscle contraction. ALS is the most common form of the motor neuron diseases. ALS often presents in its early stages with gradual muscle Spasticity, stiffness, Fasciculation, twitches, Muscle weakness, weakness, and Muscle atrophy, wasting. Motor neuron loss typically continues until the abilities to eat, speak, move, and, lastly, breathe are all lost. While only 15% of people with ALS also fully develop frontotemporal dementia, an estimated 50% face at least some minor difficulties with cognitive disorder, thinking and behavior. Depending on which of the aforementioned symptoms develops first, ALS is classified as ''limb-onset'' (b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diabetic Neuropathy
Diabetic neuropathy includes various types of nerve damage associated with diabetes mellitus. The most common form, diabetic peripheral neuropathy, affects 30% of all diabetic patients. Studies suggests that cutaneous nerve branches, such as the sural nerve, are involved in more than half of patients with diabetes 10 years after the diagnosis and can be detected with high-resolution magnetic resonance imaging. Symptoms depend on the site of nerve damage and can include motor changes such as weakness; sensory symptoms such as numbness, tingling, or pain; or autonomic changes such as urinary symptoms. These changes are thought to result from a microvascular disease, microvascular injury involving small blood vessels that supply nerves (vasa nervorum). Relatively common conditions which may be associated with diabetic neuropathy include distal symmetric polyneuropathy; Oculomotor nerve palsy, third, Fourth nerve palsy, fourth, or Sixth nerve palsy, sixth cranial nerve palsy; mononeuro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peripheral Neuropathy
Peripheral neuropathy, often shortened to neuropathy, refers to damage or disease affecting the nerves. Damage to nerves may impair sensation, movement, gland function, and/or organ function depending on which nerve fibers are affected. Neuropathies affecting motor, sensory, or autonomic nerve fibers result in different symptoms. More than one type of fiber may be affected simultaneously. Peripheral neuropathy may be acute (with sudden onset, rapid progress) or chronic (symptoms begin subtly and progress slowly), and may be reversible or permanent. Common causes include systemic diseases (such as diabetes or leprosy), hyperglycemia-induced glycation, vitamin deficiency, medication (e.g., chemotherapy, or commonly prescribed antibiotics including metronidazole and the fluoroquinolone class of antibiotics (such as ciprofloxacin, levofloxacin, moxifloxacin)), traumatic injury, ischemia, radiation therapy, excessive alcohol consumption, immune system disease, celiac disease, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MMACHC
Methylmalonic aciduria and homocystinuria type C protein (MMACHC) is a protein that in humans is encoded by the ''MMACHC'' gene. Function The C-terminal region of the product of the MMACHC gene is similar to TonB, a bacterial protein involved in energy transduction for cobalamin uptake. The MMACHC gene product catalyzes the decyanation of cyanocobalamin as well as the dealkylation of alkylcobalamins including methylcobalamin and adenosylcobalamin. This function has also been attributed to cobalamin reductases. The MMACHC gene product and cobalamin reductases enable the interconversion of cyano- and alkylcobalamins. Clinical significance Mutations are associated with combined homocystinuria and methylmalonic acidemia Methylmalonic acidemias, also called methylmalonic acidurias, are a group of inherited metabolic disorders, that prevent the body from properly breaking down proteins and fats. This leads to a buildup of a toxic level of methylmalonic acid in body .... R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
European Food Safety Authority
The European Food Safety Authority (EFSA) is the agency of the European Union (EU) that provides independent scientific advice and communicates on existing and emerging risks associated with the food chain. EFSA was established in February 2002 in Parma, Italy. It had a yearly budget of €118.6 million, and a total staff of 542 as of 2021. The work of EFSA covers all matters with a direct or indirect impact on food and feed safety, including animal health and welfare, plant protection and plant health and nutrition. EFSA supports the European Commission, the European Parliament and EU member states in taking effective and timely risk management decisions that ensure the protection of the health of European consumers and the safety of the food and feed chain. EFSA also communicates to the public in an open and transparent way on all matters within its remit. Structure Based on a regulation of 2002, the EFSA is composed of four bodies: * Management Board * Executive Direc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vitamin B12 Deficiency
Vitamin B12 deficiency, also known as cobalamin deficiency, is the medical condition in which the blood and tissue have a lower than normal level of Vitamin B12, vitamin B12. Symptoms can vary from none to severe. Mild deficiency may have few or absent symptoms. In moderate deficiency, Fatigue, feeling tired, Headache, headaches, glossitis, soreness of the tongue, Aphthous stomatitis, mouth ulcers, breathlessness, Presyncope, feeling faint, Tachycardia, rapid heartbeat, low blood pressure, pallor, hair loss, decreased ability to think and severe arthralgia, joint pain and the beginning of neurological symptoms, including Paresthesia, abnormal sensations such as ''pins and needles'', numbness and tinnitus may occur. Severe deficiency may include symptoms of cardiomyopathy, reduced heart function as well as more severe neurological symptoms, including changes in reflexes, poor muscle function, memory problems, blurred vision, irritability, ataxia, decreased Anosmia, smell and Hy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methylmercury
Methylmercury is an organometallic cation with the formula . It is the simplest organomercury compound. Methylmercury is extremely toxic, and its derivatives are the major source of organic mercury for humans. It is a bioaccumulative environmental toxicant with a 50-day half-life. Methylmercury (derived biologically from dimethylmercury) is the causative agent of the infamous Minamata disease. Methylmercury is designated as a "priority hazardous substance" according to the Directive on Environmental Quality Standards (Directive 2013/39/EU). Structure and chemistry "Methylmercury" is a shorthand for the hypothetical "methylmercury cation", sometimes written ''methylmercury(1+) cation'' or ''methylmercury(II) cation''. This functional group is composed of a methyl group Chemical bond, bonded to an atom of Mercury (element), mercury. Its chemical formula is (sometimes written as ). The Methylmercury compound has an overall charge of +1, with Hg in the +2 oxidation state. Methylmer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
