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Acute Intermittent Porphyria
Acute intermittent porphyria (AIP) is a rare Metabolism, metabolic disorder affecting the production of heme resulting from a deficiency of the enzyme porphobilinogen deaminase. It is the most common of the acute porphyrias. Signs and symptoms The clinical presentation of AIP is highly variable and non-specific. The patients are typically asymptomatic, with most gene carriers having no family history because the condition had remained latent for several generations. The syndrome marked by acute attacks affects only 10% of gene carriers. The mean age at diagnosis is 33 years old. Like other porphyrias, AIP is more likely to present in women. A distinguishing feature of AIP that separates it from other porphyrias is the absence of Photosensitivity, photosensitive Skin, cutaneous symptoms that occur in addition to acute attacks. Acute attacks AIP is one of the four porphyrias that presents as an acute attack. 90% of affected individuals never experience an Acute (medicine), acute a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Porphobilinogen
Porphobilinogen (PBG) is an organic compound that occurs in living organisms as an intermediate in the biosynthesis of porphyrins, which include critical substances like hemoglobin and chlorophyll. The structure of the molecule can be described as molecule of pyrrole with sidechains substituted for hydrogen atoms at positions 2, 3 and 4 in the ring (1 being the nitrogen atom); respectively, an aminomethyl group , an acetic acid (carboxymethyl) group , and a propionic acid (carboxyethyl) group . Biosynthesis In the first step of the porphyrin biosynthesis pathway, porphobilinogen is generated from aminolevulinate (ALA) by the enzyme ALA dehydratase. Metabolism In the typical porphyrin biosynthesis pathway, four molecules of porphobilinogen are concatenated by carbons 2 and 5 of the pyrrole ring (adjacent to the nitrogen atom) into hydroxymethyl bilane by the enzyme porphobilinogen deaminase, also known as hydroxymethylbilane synthase. Pathologies Acute intermittent porphyria c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyponatremia
Hyponatremia or hyponatraemia is a low concentration of sodium in the Serum (blood), blood. It is generally defined as a sodium concentration of less than 135 mmol/L (135 mEq/L), with severe hyponatremia being below 120 mEq/L. Symptoms can be absent, mild or severe. Mild symptoms include a Altered level of consciousness, decreased ability to think, headaches, nausea, and Balance disorder, poor balance. Severe symptoms include confusion, seizures, and coma; death can ensue. The causes of hyponatremia are typically classified by a person's body fluid status into hypovolemic, low volume, normal volume, or hypervolemic, high volume. Low volume hyponatremia can occur from diarrhea, vomiting, diuretics, and sweating. Normal volume hyponatremia is divided into cases with concentration, dilute urine and concentration, concentrated urine. Cases in which the urine is dilute include adrenal insufficiency, hypothyroidism, and polydipsia, drinking too much water or potomania, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein Biosynthesis
Protein biosynthesis, or protein synthesis, is a core biological process, occurring inside Cell (biology), cells, homeostasis, balancing the loss of cellular proteins (via Proteolysis, degradation or Protein targeting, export) through the production of new proteins. Proteins perform a number of critical functions as enzymes, structural proteins or hormones. Protein synthesis is a very similar process for both prokaryotes and eukaryotes but there are some distinct differences. Protein synthesis can be divided broadly into two phases: Transcription (biology), transcription and Translation (biology), translation. During transcription, a section of DNA encoding a protein, known as a gene, is converted into a molecule called messenger RNA (mRNA). This conversion is carried out by enzymes, known as RNA polymerases, in the cell nucleus, nucleus of the cell. In eukaryotes, this mRNA is initially produced in a premature form (Primary transcript, pre-mRNA) which undergoes post-transcriptio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzyme
An enzyme () is a protein that acts as a biological catalyst by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different molecules known as product (chemistry), products. Almost all metabolism, metabolic processes in the cell (biology), cell need enzyme catalysis in order to occur at rates fast enough to sustain life. Metabolic pathways depend upon enzymes to catalyze individual steps. The study of enzymes is called ''enzymology'' and the field of pseudoenzyme, pseudoenzyme analysis recognizes that during evolution, some enzymes have lost the ability to carry out biological catalysis, which is often reflected in their amino acid sequences and unusual 'pseudocatalytic' properties. Enzymes are known to catalyze more than 5,000 biochemical reaction types. Other biocatalysts include Ribozyme, catalytic RNA molecules, also called ribozymes. They are sometimes descr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gene
In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protein-coding genes and non-coding genes. During gene expression (the synthesis of Gene product, RNA or protein from a gene), DNA is first transcription (biology), copied into RNA. RNA can be non-coding RNA, directly functional or be the intermediate protein biosynthesis, template for the synthesis of a protein. The transmission of genes to an organism's offspring, is the basis of the inheritance of phenotypic traits from one generation to the next. These genes make up different DNA sequences, together called a genotype, that is specific to every given individual, within the gene pool of the population (biology), population of a given species. The genotype, along with environmental and developmental factors, ultimately determines the phenotype ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mutation
In biology, a mutation is an alteration in the nucleic acid sequence of the genome of an organism, virus, or extrachromosomal DNA. Viral genomes contain either DNA or RNA. Mutations result from errors during DNA or viral replication, mitosis, or meiosis or other types of damage to DNA (such as pyrimidine dimers caused by exposure to ultraviolet radiation), which then may undergo error-prone repair (especially microhomology-mediated end joining), cause an error during other forms of repair, or cause an error during replication ( translesion synthesis). Mutations may also result from substitution, insertion or deletion of segments of DNA due to mobile genetic elements. Mutations may or may not produce detectable changes in the observable characteristics ( phenotype) of an organism. Mutations play a part in both normal and abnormal biological processes including: evolution, cancer, and the development of the immune system, including junctional diversity. Mutati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antiretroviral
The management of HIV/AIDS normally includes the use of multiple antiretroviral drugs as a strategy to control HIV infection. There are several classes of antiretroviral agents that act on different stages of the HIV life-cycle. The use of multiple drugs that act on different viral targets is known as highly active antiretroviral therapy (HAART). HAART decreases the patient's total burden of HIV, maintains function of the immune system, and prevents opportunistic infections that often lead to death. HAART also prevents the transmission of HIV between serodiscordant same-sex and opposite-sex partners so long as the HIV-positive partner maintains an undetectable viral load. Treatment has been so successful that in many parts of the world, HIV has become a chronic condition in which progression to AIDS is increasingly rare. Anthony Fauci, former head of the United States National Institute of Allergy and Infectious Diseases, has written, "With collective and resolute action ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anesthetic
An anesthetic (American English) or anaesthetic (British English; see spelling differences) is a drug used to induce anesthesia — in other words, to result in a temporary loss of sensation or awareness. They may be divided into two broad classes: general anesthetics, which result in a reversible loss of consciousness, and local anesthetics, which cause a reversible loss of sensation for a limited region of the body without necessarily affecting consciousness. A wide variety of drugs are used in modern anesthetic practice. Many are rarely used outside anesthesiology, but others are used commonly in various fields of healthcare. Combinations of anesthetics are sometimes used for their synergistic and additive therapeutic effects. Adverse effects, however, may also be increased. Anesthetics are distinct from analgesics, which block only sensation of painful stimuli. Analgesics are typically used in conjunction with anesthetics to control pre-, intra-, and postop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anticonvulsant
Anticonvulsants (also known as antiepileptic drugs, antiseizure drugs, or anti-seizure medications (ASM)) are a diverse group of pharmacological agents used in the treatment of epileptic seizures. Anticonvulsants are also used in the treatment of bipolar disorder and borderline personality disorder, since many seem to act as mood stabilizers, and for the treatment of neuropathic pain. Anticonvulsants suppress the uncontrolled and excessive firing of neurons during seizures and in doing so can also prevent the spread of the seizure within the brain. Conventional antiepileptic drugs have diverse mechanisms of action but many block sodium channels or enhance γ-aminobutyric acid ( GABA) function. Several antiepileptic drugs have multiple or uncertain mechanisms of action. Next to voltage-gated sodium channels and components of the GABA system, their targets include GABAA receptors, the GABA transporter type 1, and GABA transaminase. Additional targets include voltage-gate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hormonal Contraception
Hormonal contraception refers to birth control methods that act on the endocrine system. Almost all methods are composed of steroid hormones, although in India one selective estrogen receptor modulator is marketed as a contraceptive. The original hormonal method—the combined oral contraceptive pill—was first marketed as a contraceptive in 1960. In the ensuing decades, many other delivery methods have been developed, although the oral and injectable methods are by far the most popular. Hormonal contraception is highly effective: when taken on the prescribed schedule, users of steroid hormone methods experience pregnancy rates of less than 1% per year. Perfect-use pregnancy rates for most hormonal contraceptives are usually around the 0.3% rate or less. Currently available methods can only be used by women; the development of a male hormonal contraceptive is an active research area. There are two main types of hormonal contraceptive formulations: ''combined methods'' which conta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antibiotic
An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting pathogenic bacteria, bacterial infections, and antibiotic medications are widely used in the therapy, treatment and antibiotic prophylaxis, prevention of such infections. They may either bactericide, kill or bacteriostatic agent, inhibit the growth of bacteria. A limited number of antibiotics also possess antiprotozoal activity. Antibiotics are not effective against viruses such as the ones which cause the common cold or influenza. Drugs which inhibit growth of viruses are termed antiviral drugs or antivirals. Antibiotics are also not effective against fungi. Drugs which inhibit growth of fungi are called antifungal drugs. Sometimes, the term ''antibiotic''—literally "opposing life", from the Greek language, Greek roots ἀντι ''anti'', "against" and βίος ''bios'', "life"—is broadly used to refer to any substance used against ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dieting
Dieting is the practice of eating food in a regulated way to decrease, maintain, or increase body weight, or to prevent and treat diseases such as diabetes and obesity. As weight loss depends on calorie intake, List of diets, different kinds of Calorie restriction, calorie-reduced diets, such as those emphasising particular macronutrients (low-fat diet, low-fat, low-carbohydrate diet, low-carbohydrate, etc.), have been shown to be no more effective than one another. As weight regain is common, diet success is best predicted by long-term adherence. Regardless, the outcome of a diet can vary widely depending on the individual. The first popular diet was "Banting", named after William Banting. In his 1863 pamphlet, ''Letter on Corpulence, Addressed to the Public'', he outlined the details of a particular low-carbohydrate, low-calorie diet that led to his own dramatic weight loss. Some guidelines recommend dieting to Weight loss, lose weight for people with weight-related health pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
