Vitamin B Deficiency
Protein Tyrosine Phosphatase, Non-Receptor Type 1
Boron
Complement C4a
Complement C4b
Vitamin B 12 Deficiency
Vitamin B 6
Unverricht-Lundborg Syndrome
Fructose Intolerance
Sandhoff Disease
Vitamin A
Vitamins
Vitamin D
Vitamin E
Vitamin A Deficiency
Vitamin B 12
Mutations in the organic cation/carnitine transporter OCTN2 in primary carnitine deficiency. (1/83)
Primary carnitine deficiency is an autosomal recessive disorder of fatty acid oxidation caused by defective carnitine transport. This disease presents early in life with hypoketotic hypoglycemia or later in life with skeletal myopathy or cardiomyopathy. The gene for this condition maps to 5q31.2-32 and OCTN2, an organic cation/carnitine transporter, also maps to the same chromosomal region. Here we test the causative role of OCTN2 in primary carnitine deficiency by searching for mutations in this gene in affected patients. Fibroblasts from patients with primary carnitine deficiency lacked mediated carnitine transport. Transfection of patient's fibroblasts with the OCTN2 cDNA partially restored carnitine transport. Sequencing of the OCTN2 gene revealed different mutations in two unrelated patients. The first patient was homozygous (and both parents heterozygous) for a single base pair substitution converting the codon for Arg-282 to a STOP codon (R282X). The second patient was a compound heterozygote for a paternal 1-bp insertion producing a STOP codon (Y401X) and a maternal 1-bp deletion that produced a frameshift creating a subsequent STOP codon (458X). These mutations decreased the levels of mature OCTN2 mRNA and resulted in nonfunctional transporters, confirming that defects in the organic cation/carnitine transporter OCTN2 are responsible for primary carnitine deficiency. (+info)A survey of the current clinical practice of psychiatrists and accident and emergency specialists in the United Kingdom concerning vitamin supplementation for chronic alcohol misusers. (2/83)
Although it is well known that B-vitamin deficiencies directly affecting the brain are common in alcohol misuse, no concise guidelines on the use of vitamin supplements in alcohol misusers currently exist in the UK. The purpose of this study was to assess current practice and opinion among UK physicians. Questionnaires were completed by a total of 427 physicians comprising Accident and Emergency (A&E) specialists and psychiatrists, with a response rate of 25%. The main findings were that vitamin deficiency was perceived as being uncommon amongst alcohol misusers (<25%) and there was no consensus as to which B vitamins are beneficial in treatment or the best method of administration of B-vitamin supplementation. The majority of psychiatrists favoured oral administration for prophylaxis against the Wernicke-Korsakoff syndrome in chronic alcohol misusers and parenteral therapy in patients with signs of Wernicke-Korsakoff syndrome. Whilst only just over half the A&E specialists expressed a preference, most favoured parenteral therapy in both cases. Most respondents did not currently have a unit policy/protocol on the management of vitamin supplementation in chronic alcohol misusers. Overall, the findings suggest that there is wide variation in current practice and highlight the need for guidelines in this area. (+info)B vitamins, homocysteine, and neurocognitive function in the elderly. (3/83)
Evidence of the importance of the B vitamins folic acid, vitamin B-12, and vitamin B-6 for the well-being and normal function of the brain derives from data showing neurologic and psychologic dysfunction in vitamin deficiency states and in cases of congenital defects of one-carbon metabolism. The status of these vitamins is frequently inadequate in the elderly and recent studies have shown associations between loss of cognitive function or Alzheimer disease and inadequate B vitamin status. The question that arises is whether these B vitamin inadequacies contribute to such brain malfunctions or result from aging and disease. From a theoretical standpoint, these inadequacies could give rise to impairment of methylation reactions that are crucial to the health of brain tissue. In addition or perhaps instead, these inadequacies could result in hyperhomocysteinemia, a recently identified risk factor for occlusive vascular disease, stroke, and thrombosis, any of which may result in brain ischemia. Advances in the understanding of this putative relation between inadequate vitamin status and loss of cognitive function in the elderly are likely to be slow and may depend on the outcomes of both prospective studies and longitudinal studies in which nutritional intervention is provided before cognitive decline occurs. (+info)Effect of physical activity on thiamine, riboflavin, and vitamin B-6 requirements. (4/83)
Because exercise stresses metabolic pathways that depend on thiamine, riboflavin, and vitamin B-6, the requirements for these vitamins may be increased in athletes and active individuals. Theoretically, exercise could increase the need for these micronutrients in several ways: through decreased absorption of the nutrients; by increased turnover, metabolism, or loss of the nutrients; through biochemical adaptation as a result of training that increases nutrient needs; by an increase in mitochondrial enzymes that require the nutrients; or through an increased need for the nutrients for tissue maintenance and repair. Biochemical evidence of deficiencies in some of these vitamins in active individuals has been reported, but studies examining these issues are limited and equivocal. On the basis of metabolic studies, the riboflavin status of young and older women who exercise moderately (2.5-5 h/wk) appears to be poorer in periods of exercise, dieting, and dieting plus exercise than during control periods. Exercise also increases the loss of vitamin B-6 as 4-pyridoxic acid. These losses are small and concomitant decreases in blood vitamin B-6 measures have not been documented. There are no metabolic studies that have compared thiamine status in active and sedentary persons. Exercise appears to decrease nutrient status even further in active individuals with preexisting marginal vitamin intakes or marginal body stores. Thus, active individuals who restrict their energy intake or make poor dietary choices are at greatest risk for poor thiamine, riboflavin, and vitamin B-6 status. (+info)Effects of protein and vitamin B deficiency on blood parameters and myenteric neurons of the colon of rats. (5/83)
The aims of this work were to evaluate the effects of the deficient ingestion of protein and vitamin B on the biochemical and hematologic parameters and on the NADH- and NADPH-diaphorase positive myenteric neurons. The control animals (n=10) received commercial chow and the experimental rats (n=10) received chow with protein level reduced to 8% during 120 days. At the time of killing blood was collected for assessment of the blood and hematologic parameters and the ascending colon for quantitative analysis of the neurons of the myenteric plexus. It was observed that the reduction of the protein level to 8% coupled to the reduction of the levels of vitamin B in adult rats neither led to qualitative or quantitative changes on red or white blood cells, nor decreased globulin levels, induced the formation of edema or gave rise to clinical signs typical of protein or vitamin B deficiency. On the other hand, the experimental protocol led to less weight gain, change on the body composition with fat deposition; decrease of the values of serum total protein and albumin; reduction of the area of colon and density of nitrergic and NADH-diaphorase myenteric neurons inferior to the expected. (+info)Effects of fatty liver induced by niacin-free diet with orotic acid on the metabolism of tryptophan to niacin in rats. (6/83)
The effects of dietary orotic acid on the metabolism of tryptophan to niacin in weaning rats was investigated. The rats were fed with a niacin-free, 20% casein diet containing 0% (control diet) or 1% orotic acid diet (test diet) for 29 d. Retardation of growth, development of fatty liver, and enlargement of liver were observed in the test group in comparison with the control group. The concentrations of NAD and NADP in liver significantly decreased, while these in blood did not decrease compared to the control group. The formation of the upper metabolites of tryptophan to niacin such as anthranilic acid, kynurenic acid, and 3-hydroxyanthranilic acid were not affected, but the quinolinic acid and beyond, such as nicotinamide, N1-methylnicotinamide, N1-methyl-2-pyridone-5-carboxamide, and N1-methyl-4-pyridone-3-carboxamide, were significantly reduced by the administration of orotic acid. Therefore, the conversion ratio of tryptophan to niacin significantly decreased in the test group in comparison with the control group. (+info)Preconception homocysteine and B vitamin status and birth outcomes in Chinese women. (7/83)
BACKGROUND: The associations between homocysteine, B vitamin status, and pregnancy outcomes have not been examined prospectively. OBJECTIVE: We assessed the associations of preconception homocysteine and B vitamin status with preterm birth and birth of low-birth-weight (LBW) and small-for-gestational-age (SGA) infants in Chinese women. DESIGN: This was a case-control study of women aged 21-34 y. Preterm cases (n = 29) delivered living infants at <37 wk gestation; term controls (n = 405) delivered infants at > or =37 wk. LBW cases (n = 33) had infants weighing <2500 g; normal-birth-weight controls (n = 390) had infants weighing > or =2500 g. SGA cases (n = 65) had infants below the 10th percentile of weight-for-gestational-age; appropriate-for-gestational-age controls (n = 358) had infants above this cutoff. Nonfasting plasma concentrations of homocysteine, folate, and vitamins B-6 and B-12 were measured before conception. RESULTS: Elevated homocysteine (> or =12.4 micro mol/L) was associated with a nearly 4-fold higher risk of preterm birth (OR: 3.6; 95% CI: 1.3, 10.0; P < 0.05). The risk of preterm birth was 60% lower among women with vitamin B-12 > or =258 pmol/L than among vitamin B-12-deficient women (OR: 0.4; 95% CI: 0.2, 0.9; P < 0.05) and was 50% lower among women with vitamin B-6 > or =30 nmol/L than among vitamin B-6-deficient women (OR: 0.5; 95% CI: 0.2, 1.2; NS). Folate status was not associated with preterm birth, and homocysteine and B vitamin status were not associated with LBW or SGA status. CONCLUSIONS: Elevated homocysteine and suboptimal vitamin B-12 and B-6 status may increase the risk of preterm birth. These results need to be confirmed in larger prospective studies. (+info)A preliminary study of circulating vitamins in a Puerto Rican migrant farm population in New Jersey. (8/83)
A preliminary survey of circulating vitamin B12 biotin, folate, thiamin, riboflavin, vitamin B6, pantothenate, nicotinate, and vitamin A & B-carotene of 53 Puerto Rican migrant farm workers was undertaken. Results indicate that hypovitaminemia existed particularly for vitamin B12, vitamin B6 and vitamin A. (+info)Vitamin B deficiency refers to a condition where an individual's body lacks adequate amounts of one or more essential Vitamin B compounds, including Vitamin B1 (thiamin), Vitamin B2 (riboflavin), Vitamin B3 (niacin), Vitamin B5 (pantothenic acid), Vitamin B6 (pyridoxine), Vitamin B7 (biotin), Vitamin B9 (folate), and Vitamin B12 (cobalamin). These water-soluble vitamins play crucial roles in various bodily functions, such as energy production, nerve function, DNA repair, and the formation of red blood cells.
Deficiency in any of these Vitamin B compounds can lead to specific health issues. For instance:
1. Vitamin B1 (thiamin) deficiency can cause beriberi, a condition characterized by muscle weakness, peripheral neuropathy, and heart failure.
2. Vitamin B2 (riboflavin) deficiency may result in ariboflavinosis, which presents with inflammation of the mouth and tongue, anemia, and skin disorders.
3. Vitamin B3 (niacin) deficiency can lead to pellagra, marked by diarrhea, dermatitis, dementia, and, if left untreated, death.
4. Vitamin B5 (pantothenic acid) deficiency is rare but can cause acne-like skin lesions and neurological symptoms.
5. Vitamin B6 (pyridoxine) deficiency may result in anemia, peripheral neuropathy, seizures, and skin disorders.
6. Vitamin B7 (biotin) deficiency can cause hair loss, skin rashes, and neurological symptoms.
7. Vitamin B9 (folate) deficiency can lead to megaloblastic anemia, neural tube defects in fetuses during pregnancy, and increased homocysteine levels, which may contribute to cardiovascular disease.
8. Vitamin B12 (cobalamin) deficiency can cause pernicious anemia, characterized by fatigue, weakness, neurological symptoms, and, if left untreated, irreversible nerve damage.
Deficiencies in these vitamins can arise from inadequate dietary intake, malabsorption syndromes, or certain medications that interfere with absorption or metabolism. It is essential to maintain a balanced diet and consider supplementation if necessary under the guidance of a healthcare professional.
Protein Tyrosine Phosphatase, Non-Receptor Type 1 (PTPN1) is a type of enzyme that belongs to the protein tyrosine phosphatase (PTP) family. PTPs play crucial roles in regulating various cellular processes by removing phosphate groups from phosphorylated tyrosine residues on proteins, thereby controlling the activity of many proteins involved in signal transduction pathways.
PTPN1, also known as PTP1B, is a non-receptor type PTP that is localized to the endoplasmic reticulum and cytosol of cells. It has been extensively studied due to its important role in regulating various cellular signaling pathways, including those involved in metabolism, cell growth, differentiation, and survival.
PTPN1 dephosphorylates several key signaling molecules, such as the insulin receptor, epidermal growth factor receptor (EGFR), and Janus kinase 2 (JAK2). By negatively regulating these signaling pathways, PTPN1 acts as a tumor suppressor and plays a role in preventing excessive cell growth and survival. However, dysregulation of PTPN1 has been implicated in various diseases, including diabetes, obesity, and cancer.
Boron is a chemical element with the symbol B and atomic number 5. It is a metalloid that is light-colored, hard, and highly resistant to corrosion. In its crystalline form, boron is nearly as hard as diamond.
In medicine, boron compounds have been studied for their potential therapeutic uses, particularly in the treatment of cancer. For example, boron neutron capture therapy (BNCT) is a type of radiation therapy that involves the use of boron-containing compounds to selectively deliver radiation to cancer cells.
Boron is also an essential micronutrient for plants and some animals, including humans. However, excessive exposure to boron can be toxic to humans and other organisms. Therefore, it is important to maintain appropriate levels of boron in the body and environment.
Complement C4a is a protein fragment or cleavage product generated during the activation of the complement system, which is a part of the immune system. The complement system helps to eliminate pathogens and damaged cells by marking them for destruction and direct lysis. Complement component 4 (C4) is one of the key proteins in this cascade, and it gets cleaved into C4a and C4b during the activation process.
C4a is a small anaphylatoxin with a molecular weight of approximately 9 kDa. It has chemotactic properties, meaning it can attract immune cells like neutrophils to the site of complement activation. Additionally, C4a can induce histamine release from mast cells and basophils, contributing to local inflammation. However, its precise physiological role in the immune response is not entirely clear, and dysregulation of C4a production has been implicated in several pathological conditions, such as autoimmune diseases and allergies.
Complement C4b is a protein fragment that is formed during the activation of the complement system, which is a part of the immune system. The complement system helps to eliminate pathogens and damaged cells from the body by tagging them for destruction and attracting immune cells to the site of infection or injury.
C4b is generated when the C4 protein is cleaved into two smaller fragments, C4a and C4b, during the activation of the classical or lectin pathways of the complement system. C4b then binds covalently to the surface of the target cell or pathogen, forming a complex with other complement proteins that can create a membrane attack complex (MAC) and cause cell lysis.
C4b can also act as an opsonin, coating the surface of the target cell or pathogen and making it easier for immune cells to recognize and phagocytose them. Additionally, C4b can activate the alternative pathway of the complement system, leading to further amplification of the complement response.
Vitamin B12 deficiency is a condition characterized by insufficient levels of vitamin B12 in the body, leading to impaired production of red blood cells, nerve function damage, and potential neurological complications. Vitamin B12 is an essential nutrient that plays a crucial role in DNA synthesis, fatty acid metabolism, and maintaining the health of the nervous system.
The medical definition of vitamin B12 deficiency includes:
1. Reduced serum or whole blood vitamin B12 concentrations (typically below 200 pg/mL or 145 pmol/L)
2. Presence of clinical symptoms and signs, such as:
* Fatigue, weakness, and lethargy
* Pale skin, shortness of breath, and heart palpitations due to anemia (megaloblastic or macrocytic anemia)
* Neurological symptoms like numbness, tingling, or burning sensations in the hands and feet (peripheral neuropathy), balance problems, confusion, memory loss, and depression
3. Laboratory findings consistent with deficiency, such as:
* Increased mean corpuscular volume (MCV) of red blood cells
* Reduced numbers of red and white blood cells and platelets in severe cases
* Elevated homocysteine and methylmalonic acid levels in the blood due to impaired metabolism
The most common causes of vitamin B12 deficiency include dietary insufficiency (common in vegetarians and vegans), pernicious anemia (an autoimmune condition affecting intrinsic factor production), gastrointestinal disorders (such as celiac disease, Crohn's disease, or gastric bypass surgery), and certain medications that interfere with vitamin B12 absorption.
Untreated vitamin B12 deficiency can lead to severe complications, including irreversible nerve damage, cognitive impairment, and increased risk of cardiovascular diseases. Therefore, prompt diagnosis and treatment are essential for preventing long-term health consequences.
Medical Definition of Vitamin B6:
Vitamin B6, also known as pyridoxine, is a water-soluble vitamin that plays a crucial role in various bodily functions. It is involved in the process of making serotonin and norepinephrine, which are chemicals that transmit signals in the brain. Vitamin B6 is also necessary for the formation of myelin, a protein layer that forms around nerve cells. Additionally, it helps the body to metabolize proteins, carbohydrates, and fats, and is involved in the creation of red blood cells.
Vitamin B6 can be found in a wide variety of foods, including poultry, seafood, bananas, potatoes, and fortified cereals. A deficiency in vitamin B6 can lead to anemia, confusion, and a weakened immune system. On the other hand, excessive intake of vitamin B6 can cause nerve damage and skin lesions. It is important to maintain appropriate levels of vitamin B6 through a balanced diet and, if necessary, supplementation under the guidance of a healthcare provider.
Unverricht-Lundborg syndrome, also known as Progressive Myoclonus Epilepsy type 1 or PME1, is a rare inherited neurological disorder characterized by progressive myoclonus (involuntary jerking movements), tonic-clonic seizures (grand mal seizures), and sometimes cognitive decline. It typically begins in childhood or adolescence. The condition is caused by mutations in the CSTB gene, which provides instructions for making a protein called cystatin B that helps regulate the activity of enzymes involved in brain function. The exact role of cystatin B in the brain and how its deficiency leads to Unverricht-Lundborg syndrome is not fully understood.
Fructose intolerance, also known as hereditary fructose intolerance (HFI), is a genetic disorder that affects the body's ability to metabolize the sugar called fructose, which is found in fruits, vegetables, and processed foods. It is caused by a deficiency of an enzyme called aldolase B, which is necessary for the breakdown and absorption of fructose in the liver.
When individuals with fructose intolerance consume food or drinks containing fructose, the undigested fructose accumulates in the bloodstream and gets absorbed by other organs, leading to a range of symptoms such as abdominal pain, bloating, diarrhea, vomiting, and low blood sugar. Prolonged exposure to high levels of fructose can also cause liver damage, kidney failure, and growth retardation in children.
The diagnosis of fructose intolerance is usually made through a combination of clinical symptoms, genetic testing, and a fructose tolerance test. The treatment for fructose intolerance involves avoiding foods and drinks that contain fructose or limiting their consumption to very small amounts. In some cases, supplementation with enzyme replacement therapy may be recommended.
Sandhoff disease is a rare inherited disorder that affects the nervous system. It's a type of GM2 gangliosidosis, which is a group of conditions characterized by the body's inability to break down certain fats (lipids) called gangliosides.
In Sandhoff disease, deficiencies in the enzymes hexosaminidase A and B lead to an accumulation of GM2 ganglioside in various cells, particularly in nerve cells of the brain. This accumulation results in progressive damage to the nervous system.
The symptoms of Sandhoff disease typically appear between 6 months and 2 years of age and can include developmental delay, seizures, an exaggerated startle response, muscle weakness, loss of motor skills, and vision and hearing loss. The condition is often fatal by around age 3. It's caused by mutations in the HEXB gene, and it's inherited in an autosomal recessive manner, meaning an individual must inherit two copies of the mutated gene (one from each parent) to develop the disease.
Medical Definition of Vitamin A:
Vitamin A is a fat-soluble vitamin that is essential for normal vision, immune function, and cell growth. It is also an antioxidant that helps protect the body's cells from damage caused by free radicals. Vitamin A can be found in two main forms: preformed vitamin A, which is found in animal products such as dairy, fish, and meat, particularly liver; and provitamin A carotenoids, which are found in plant-based foods such as fruits, vegetables, and vegetable oils.
The most active form of vitamin A is retinoic acid, which plays a critical role in the development and maintenance of the heart, lungs, kidneys, and other organs. Vitamin A deficiency can lead to night blindness, dry skin, and increased susceptibility to infections. Chronic vitamin A toxicity can cause nausea, dizziness, headaches, coma, and even death.
Vitamins are organic substances that are essential in small quantities for the normal growth, development, and maintenance of life in humans. They are required for various biochemical functions in the body such as energy production, blood clotting, immune function, and making DNA.
Unlike macronutrients (carbohydrates, proteins, and fats), vitamins do not provide energy but they play a crucial role in energy metabolism. Humans require 13 essential vitamins, which can be divided into two categories: fat-soluble and water-soluble.
Fat-soluble vitamins (A, D, E, and K) are stored in the body's fat tissues and liver, and can stay in the body for a longer period of time. Water-soluble vitamins (B-complex vitamins and vitamin C) are not stored in the body and need to be replenished regularly through diet or supplementation.
Deficiency of vitamins can lead to various health problems, while excessive intake of certain fat-soluble vitamins can also be harmful due to toxicity. Therefore, it is important to maintain a balanced diet that provides all the essential vitamins in adequate amounts.
Vitamin D is a fat-soluble secosteroid that is crucial for the regulation of calcium and phosphate levels in the body, which are essential for maintaining healthy bones and teeth. It can be synthesized by the human body when skin is exposed to ultraviolet-B (UVB) rays from sunlight, or it can be obtained through dietary sources such as fatty fish, fortified dairy products, and supplements. There are two major forms of vitamin D: vitamin D2 (ergocalciferol), which is found in some plants and fungi, and vitamin D3 (cholecalciferol), which is produced in the skin or obtained from animal-derived foods. Both forms need to undergo two hydroxylations in the body to become biologically active as calcitriol (1,25-dihydroxyvitamin D3), the hormonally active form of vitamin D. This activated form exerts its effects by binding to the vitamin D receptor (VDR) found in various tissues, including the small intestine, bone, kidney, and immune cells, thereby influencing numerous physiological processes such as calcium homeostasis, bone metabolism, cell growth, and immune function.
Medical Definition of Vitamin E:
Vitamin E is a fat-soluble antioxidant that plays a crucial role in protecting your body's cells from damage caused by free radicals, which are unstable molecules produced when your body breaks down food or is exposed to environmental toxins like cigarette smoke and radiation. Vitamin E is also involved in immune function, DNA repair, and other metabolic processes.
It is a collective name for a group of eight fat-soluble compounds that include four tocopherols and four tocotrienols. Alpha-tocopherol is the most biologically active form of vitamin E in humans and is the one most commonly found in supplements.
Vitamin E deficiency is rare but can occur in people with certain genetic disorders or who cannot absorb fat properly. Symptoms of deficiency include nerve and muscle damage, loss of feeling in the arms and legs, muscle weakness, and vision problems.
Food sources of vitamin E include vegetable oils (such as sunflower, safflower, and wheat germ oil), nuts and seeds (like almonds, peanuts, and sunflower seeds), and fortified foods (such as cereals and some fruit juices).
Vitamin A deficiency (VAD) is a condition that occurs when there is a lack of vitamin A in the diet. This essential fat-soluble vitamin plays crucial roles in vision, growth, cell division, reproduction, and immune system regulation.
In its severe form, VAD leads to xerophthalmia, which includes night blindness (nyctalopia) and keratomalacia - a sight-threatening condition characterized by dryness of the conjunctiva and cornea, with eventual ulceration and perforation. Other symptoms of VAD may include Bitot's spots (foamy, triangular, white spots on the conjunctiva), follicular hyperkeratosis (goose bump-like bumps on the skin), and increased susceptibility to infections due to impaired immune function.
Vitamin A deficiency is most prevalent in developing countries where diets are often low in animal source foods and high in plant-based foods with low bioavailability of vitamin A. It primarily affects children aged 6 months to 5 years, pregnant women, and lactating mothers. Prevention strategies include dietary diversification, food fortification, and supplementation programs.
Vitamin B12, also known as cobalamin, is a water-soluble vitamin that plays a crucial role in the synthesis of DNA, formation of red blood cells, and maintenance of the nervous system. It is involved in the metabolism of every cell in the body, particularly affecting DNA regulation and neurological function.
Vitamin B12 is unique among vitamins because it contains a metal ion, cobalt, from which its name is derived. This vitamin can be synthesized only by certain types of bacteria and is not produced by plants or animals. The major sources of vitamin B12 in the human diet include animal-derived foods such as meat, fish, poultry, eggs, and dairy products, as well as fortified plant-based milk alternatives and breakfast cereals.
Deficiency in vitamin B12 can lead to various health issues, including megaloblastic anemia, fatigue, neurological symptoms such as numbness and tingling in the extremities, memory loss, and depression. Since vitamin B12 is not readily available from plant-based sources, vegetarians and vegans are at a higher risk of deficiency and may require supplementation or fortified foods to meet their daily requirements.