Persius/hicric huggingface dataset:
4-Aminobenzoic acid

# Overview
4-Aminobenzoic acid (also known as para-aminobenzoic acid or PABA) is an organic compound with the molecular formula C7H7NO2.  PABA is a white crystalline substance that is only slightly soluble in water.  It consists of a benzene ring substituted with an amino group and a carboxylic acid.

# Functions

## Organic
PABA is an essential nutrient for some bacteria and is sometimes called Vitamin Bx.  However, PABA is not essential to human health, and is therefore not officially classified as a vitamin.  Although humans lack the ability to synthesize folate from PABA, it is sometimes marketed as an essential nutrient under the premise that it can stimulate intestinal bacteria.
PABA is an intermediate in bacterial synthesis of folate.  Sulfonamides are chemically similar to PABA, and their antibacterial activity is due to their ability to interfere with conversion of PABA to folate by dihydropteroate synthetase, and subsequent utilization, by bacteria.

## Industrial
In the past, PABA has been widely used as a UV filter in sunscreen formulations. However, there have been inconclusive studies on whether it increases the formation of a particular DNA defect in human cells, thus increasing the risk of skin cancer. Currently, safer and more effective derivatives of PABA, such as octyl dimethyl PABA, are more commonly used.
The potassium salt is used as a drug against fibrotic skin disorders under the trade name POTABA. PABA is also occasionally used in pill form by sufferers of Irritable bowel syndrome to treat the associated gastrointestinal symptoms.
PABA also finds use in the manufacture of esters, folic acid, and azo dyes.
Imidazolidinyl urea

# Overview
Imidazolidinyl urea is an antimicrobial preservative used in cosmetics. It is chemically related to diazolidinyl urea which is used in the same way. Imidazolidinyl urea acts as a formaldehyde releaser.

# Safety
Some people have a contact allergy to imidazolidinyl urea causing dermatitis. Such people are often also allergic to diazolidinyl urea.

# Chemistry
Imidazolidinyl urea was poorly characterized until recently and still has a wrong CAS structure assigned to it. New data show that the hydroxymethyl functional group of the imidazolidine ring is attached to the carbon, not the nitrogen atom :

## Synthesis
Imidazolidinyl urea is produced by the chemical reaction of allantoin and formaldehyde in the presence of sodium hydroxide solution and heat. The reaction mixture is then neutralized with hydrochloric acid and evaporated:
2 Allantoin + 3 H2C=O  Imidazolidinyl urea
Commercial imidazolidinyl urea is a mixture of different formaldehyde addition products including polymers.
8-Hyydroxyquinoline

# Overview
8-Hydroxyquinoline is an organic compound with the formula C9H7NO.  It is a derivative of the heterocycle quinoline by placement of an OH group on carbon number 8.  This light yellow compound is widely used commercially, although under a variety of names.

# Synthesis
It is usually prepared from quinoline-8-sulfonic acid and from a Skraup synthesis from 2-aminophenol.

# As a chelating agent
8-Hydroxyquinoline is a monoprotic bidentate chelating agent.  Related ligands are the Schiff bases derived from salicylaldehyde, such as salicylaldoxime and salen. In neutral solution, the hydroxyl is in the protonated form (pKa=9.89) and the nitrogen is not protonated (pKa=5.13). However, an excited-state zwitterionic isomer exists in which H+ is transferred from the oxygen (giving an oxygen anion) to the nitrogen (giving a protonated nitrogen cation).

# Applications
The complexes as well as the heterocycle itself exhibit antiseptic, disinfectant, and pesticide properties, functioning as a transcription inhibitor. Its solution in alcohol is used as liquid bandages. It once was of interest as an anti-cancer drug.
The reaction of 8-hydroxyquinoline with aluminium(III) results in Alq3, a common component of organic light-emitting diodes (OLED's).  Variations in the substituents on the quinoline rings affect its luminescence properties.
The roots of the invasive plant Centaurea diffusa release 8-hydroxyquinoline, which has a negative effect on plants that have not co-evolved with it.
Hydroxyquinoline was used as a stabilizer of hydrogen peroxide in a rocket fuel oxidizer (T-Stoff) for the German Messerschmitt Me 163 Komet in World War 2.
Abacavir lamivudine

# Overview
Abacavir/lamivudine (INNs) is a combination drug for the treatment of HIV infection. It is marketed as Kivexa in most countries except for the United States, where it is branded as Epzicom. It is a fixed dose combination of  lamivudine (3TC, Epivir) and abacavir  (ABC, Ziagen).
Lamivudine and abacavir are both nucleoside reverse transcriptase inhibitors (NRTI).
It was approved by the FDA on August 2, 2004. It is marketed by ViiV Healthcare.

# Category
Antiretroviral

# US Brand Names
EPZICOM

# FDA Package Insert
Description

# Mechanism of Action

## Abacavir
Abacavir is a carbocyclic synthetic nucleoside analogue. Abacavir is converted by cellular enzymes to the active metabolite, carbovir triphosphate (CBV-TP), an analogue of deoxyguanosine-5-triphosphate (dGTP). CBV-TP inhibits the activity of HIV-1 reverse transcriptase (RT) both by competing with the natural substrate dGTP and by its incorporation into viral DNA. The lack of a 3-OH group in the incorporated nucleotide analogue prevents the formation of the 5 to 3 phosphodiester linkage essential for DNA chain elongation, and therefore, the viral DNA growth is terminated. CBV-TP is a weak inhibitor of cellular DNA polymerases , , and .

## Lamivudine
Lamivudine is a synthetic nucleoside analogue. Intracellularly lamivudine is phosphorylated to its active 5-triphosphate metabolite, lamivudine triphosphate (3TC-TP). The principal mode of action of 3TC-TP is inhibition of RT via DNA chain termination after incorporation of the nucleotide analogue. CBV-TP and 3TC-TP are weak inhibitors of cellular DNA polymerases , , and .
Granular cell tumor
Synonyms and keywords: Abrikossoff's tumor; granular cell myoblastoma; granular cell nerve sheath tumor; granular cell schwannoma

# Overview
Granular cell tumor, which was referred to historically as a granular cell myoblastoma, is a tumor that can develop on any skin or mucosal surface, but occurs on the tongue 40% of the time.  Currently, it is believed that the affected cells are of neural origin.  The usual presentation is of a slow growing, nontender nodule.  Microscopically, the granular cell tumor can be mistaken for squamous cell carcinoma.

# Pathology
Granular cell tumors show similarity to neural tissue, as can be demonstrated by immunohistochemistry and ultrastructural evidence using electron microscopy.  
Multiple granular cell tumors may seen in the context of LEOPARD syndrome, due to a mutation in the PTPN11 gene.

# Epidemiology
Granular cell tumors can affect all parts of the body; however, the head and neck areas are affected 45% to 65% of the time.  Of the head and neck cases 70% of lesions are located intraorally (tongue, oral mucosa, hard palate).  The next most common location that lesions are found in the head and neck area is the larynx (10%).  Granular cell tumors are also found in the internal organs, particularly in the upper aerodigestive tract.  
The usual presentation is of slow growing behavior, forming a polygonal accumulation of secondary lysosomes in the cytoplasm.  Granular cell tumors are typically solitary and are rarely larger than three centimeters.  This type of tumor has been found to be both benign and malignant, although malignancy is rare and comprises only 2% of all granular cell tumors.

# Treatment
The primary method for treatment is surgical, not medical.  Radiation and chemotherapy are not needed for benign lesions and are not effective for malignant lesions.  Benign granular cell tumors have a recurrence rate of 2% to 8% when resection margins are deemed clear of tumor infiltration.  When the resection margins of a benign granular cell tumor are positive for tumor infiltration the recurrence rate is increased to 20%.  Malignant lesions are aggressive and difficult to eradicate with surgery and have a recurrence rate of 32%.
Absorption spectrum

# Overview
A material's absorption spectrum shows the fraction of incident electromagnetic radiation absorbed by the material over a range of frequencies.  An absorption spectrum is, in a sense, the opposite of an emission spectrum.
Every chemical element has absorption lines at several particular wavelengths corresponding to the differences between the energy levels of its atomic orbitals. For example, an object that absorbs blue, green and yellow light will appear red when viewed under white light. Absorption spectra can therefore be used to identify elements present in a gas or liquid. This method is used in deducing the presence of elements in stars and other gaseous objects which cannot be measured directly.

# Explanation
Atoms and molecules may change states when they absorb specific amounts of energy. Atomic states are defined by the arrangement of electrons in atomic orbitals. An electron in some orbital may be excited to a more energetic orbital by absorbing exactly one photon which has energy equal to the energy difference of the two orbitals.
Molecular states are defined by the molecule's modes of vibration and rotation. These vibrational and rotational modes are quantized, similar to the atomic orbitals, and may be excited by absorbing single photons.
In both the atomic and molecular cases, the excited states do not persist: after some random amount of time, the atoms and molecules revert back to their original, lower energy state. In atoms, the excited electron returns to a lower orbital, emitting a photon. In molecules, the vibrational or rotational mode decays, also emitting a photon.
When this decay occurs, the photon produced is not necessarily emitted in the same direction as the original photon. The most common angle of this has been shown to be about 45 degrees of the original photon. This applies to any situation where gases lie between a light source and an observer: the observer will see gaps in the spectrum of the light corresponding to the wavelengths of the photons which were absorbed. These gaps occur despite the re-emission of photons because the re-emitted photons are equally likely to travel in all directions, and it is statistically unlikely to travel along the original path to the observer. These gaps appear as black lines in an image of the spectrum.
Isovaleric acidemia

# Overview
Isovaleric acidemia is a rare genetic disorder in which the body is unable to process certain proteins properly. People with this disorder have inadequate levels of an enzyme that helps break down the amino acid leucine. It is closely related to the genetic metabolic disorder Maple syrup urine disease.

# Historical Perspective

# Classification

# Pathophysiology

## Genetics
Isovaleric acidemia is estimated to affect at least 1 in 250,000 births in the United States. The condition is inherited in an autosomal recessive pattern, caused by mutations in both copies of the IVD gene.
The enzyme encoded by IVD, isovaleric acid-CoA dehydrogenase (EC 1.3.99.10), plays an essential role in breaking down proteins from the diet. Specifically, the enzyme is responsible for the third step in processing leucine, an amino acid that is part of many proteins. If a mutation in the IVD gene reduces or eliminates the activity of this enzyme, the body is unable to break down leucine properly. As a result, a molecule called isovaleric acid and related compounds build up to harmful levels, damaging the brain and nervous system.

# Causes

# Differentiating Isovaleric acidemia from Other Diseases

# Epidemiology and Demographics

# Risk Factors

# Screening

# Natural History, Complications, and Prognosis

# Diagnosis

## Diagnostic Criteria

## History and Symptoms
A characteristic feature of isovaleric acidemia is a distinctive odor of sweaty feet. This odor is caused by the buildup of a compound called isovaleric acid in affected individuals.
In about half of cases, the signs and symptoms of this disorder become apparent within a few days after birth and include poor feeding, vomiting, seizures, and lack of energy that can progress to coma. These medical problems are typically severe and can be life-threatening. In the other half of cases, the signs and symptoms of the disorder appear during childhood and may come and go over time. They are often triggered by an infection or by eating an increased amount of protein-rich foods.
The urine of newborn can be screened with mass spectrometry for isovaleric acid, allowing for presymptomatic diagnosis.

## Physical Examination

## Laboratory Findings

## Imaging Findings

## Other Diagnostic Studies

# Treatment

## Medical Therapy

## Surgery

## Primary Prevention

## Secondary Prevention
Acne scar treatment
There are several forms of treatment for acne scars in current usage.

# Dermabrasion
Dermabrasion is a cosmetic medical procedure in which the surface of the skin is removed by abrasion (sanding). 
It is used to remove sun-damaged skin and to remove or lessen scars and dark spots on the skin. The procedure is very painful and usually requires a general anaesthetic or twilight anaesthesia, in which the patient is still partly conscious Afterward, the skin is very red and raw-looking, and it takes several months for the skin to regrow and heal. Dermabrasion is useful for scar removal when the scar is raised above the surrounding skin, but is less effective with sunken scars.
In the past, dermabrasion was done using a small, sterilized, electric chair. In the past decade, it has become more common to use a CO2 or Erbium:YAG laser. Laser dermabrasion is much easier to control, much easier to gauge, and is practically bloodless compared to classic dermabrasion.

# Laser therapy
Fractional Laser resurfacing is a procedure which wounds the skin using microscopic pulses of light to wound the skin. Over the course of several treatments scars are softened as the body regenerates the areas of microthermal wounding. Several lasers are now on the market such as the Fraxel Laser, Affirm Laser, and Pixel Laser.
Laser resurfacing is a technique used during laser surgery wherein molecular bonds of a material are dissolved by a laser.

# Chemical therapy
Chemical peels improves and smooths the texture of the facial skin using a chemical solution that causes the skin to blister and eventually peel off. The regenerated skin is usually smoother and less wrinkled and scarred than the old skin.

# Surgical therapy
Subcision is a process used to treat deep rolling scars left behind by acne or other skin diseases. Essentially the process involves separating the skin tissue in the affected area from the deeper scar tissue. This allows the blood to pool under the affected area, eventually causing the deep rolling scar to level off with the rest of the skin area. Once the skin has leveled, treatments such as laser resurfacing, microdermabrasion or chemical peels can be used to smooth out the scarred tissue.
Hypoprothrombinemia
Hypoprothrombinemia is a blood disorder in which a deficiency of prothrombin (Factor II) results in impaired blood clotting, leading to an increased physiological risk for bleeding, especially in the gastrointestinal system, cranial vault, and superficial integumentary system.

# Causes
Hypoprothrombinemia can be the result of a genetic defect or it may be acquired as the result of another disease process, or an adverse effect of medication such as Sulfasalazine, aspirin.  For example, 5-10% of patients with Systemic lupus erythematosus exhibit acquired hypoprothrombinemia due to the presence of autoantibodies which bind to prothrombin and remove it from the bloodstream (lupus anticoagulant-hypoprothrombinaemia syndrome).

# Treatment
Hypoprothrombinemia can be treated with periodic infusions of purified prothrombin complexes.
Acroangiodermatitis
Synonyms and keywords: Mali acroangiodermatitis; Pseudo-Kaposi's sarcoma.

# Overview
Acroangiodermatitis of Mali (also known as "Mali acroangiodermatitis" and "Pseudo-Kaposi's sarcoma") is a rare cutaneous condition often characterized by purplish-blue to brown papules and plaques on the medial and lateral malleolus of both legs.:1604
Acroangiodermatitis is a rare skin condition characterised by hyperplasia of pre-existing vasculature due to venous hypertension from severe chronic venous stasis. It is associated with amputees, haemodialysis (HD) patients with arteriovenous (AV) shunts, and patients with paralysed legs, hepatitis C, chronic venous insufficiency or AV malformations (AVM). Patients present with itchy, painful, confluent, violaceous or brown-black macules, papules or plaques usually at the distal lower limbs. There may be ulceration and bleeding. The histologic features are capillary proliferation and perivascular inflammation involving eosinophils in the dermis with minimal epidermal changes. Management includes compression therapy, wound care and surgical correction of AVM. Dapsone combined with leg elevation and compression, and erythromycin for HD patients with AV fistulas have also been reported. The lesions may persist for years with complications like ulceration, bleeding and infection.

# Differential Diagnosis
Acroangiodermatitis should be differentiated from other conditions presenting as purplish-blue to brown papules and plaques on extremities. The differentials include the following:

# Physical examination

## Gallery
- Acroangiodermatitis. Adapted from [
- Acroangiodermatitis. Adapted from [
- Acroangiodermatitis. Adapted from [
Active immunization
Active immunization is where an actual microbe is taken in by a person. Antibodies are created by the recipient and are stored permanently.
Active immunization can occur naturally when an untreated microbe is received by a person who has not yet come into contact with the microbe and has no pre-made antibodies for defense. The immune system will eventually create antibodies for the microbe, but this is a slow process and, if the microbe is deadly, there may not be enough time for the antibodies to begin being used.
Artificial active immunization is where the microbe is injected into the person before they are able to take it in naturally. The microbe is treated, so that it will not harm the infected person. Depending on the type of disease, this technique also works with dead microbes, parts of the microbe, or treated toxins from the microbe.
Acute phase protein

# Overview
Acute-phase proteins are a class of proteins whose plasma concentrations increase (positive acute phase proteins) or decrease (negative acute phase proteins) in response to inflammation. This response is called the acute-phase reaction (also called acute phase response).
In response to injury, local inflammatory cells (neutrophil granulocytes and macrophages) secrete a number of cytokines into the bloodstream, most notable of which are the interleukins IL-1, IL-6 and IL-8, and TNF-.
The liver responds by producing a large number of acute-phase reactants.

# Examples
The notable are:
- D-dimer protein
- C-reactive protein
- Mannose-binding protein
- Alpha 1-antitrypsin
- Alpha 1-antichymotrypsin
- Alpha 2-macroglobulin
- some coagulation factors (Fibrinogen, prothrombin, factor VIII, von Willebrand factor, plasminogen)
- Complement factors
- Ferritin
- Serum amyloid P component (see amyloid)
- Serum amyloid A
- Prealbumin
Serum albumin concentrations fall in acute disease states.  For this reason albumin is sometimes referred to as a negative acute phase protein.

# Clinical significance
Measurement of acute phase proteins is a useful marker of inflammation in both medical and veterinary clinical pathology. It correlates with the erythrocyte sedimentation rate (ESR).
Phenylpropanolamine
Please Take Over This Page and Apply to be Editor-In-Chief for this topic: 
There can be one or more than one Editor-In-Chief. You may also apply to be an Associate Editor-In-Chief of one of the subtopics below. Please mail us  to indicate your interest in serving either as an Editor-In-Chief of the entire topic or as an Associate Editor-In-Chief for a subtopic. Please be sure to attach your CV and or biographical sketch.
Phenylpropanolamine (PPA)  is a drug of the phenethylamine family used as a decongestant and also as an appetite suppressant. In veterinary medicine, it is used to control urinary incontinence in dogs.

# Chemistry
There are four optical isomers of phenylpropanolamine: d- and l-norephedrine, and d- and l-norpseudoephedrine. D-norpseudoephedrine is also known as cathine, and occurs naturally in the stimulant plant Catha edulis (khat). This isomer is commonly used in European medications described as "phenylpropanolamine", whereas in the United States a racemic mixture of d,l-norephedrine is usual.
Just as ephedrine is chemically reduced into methamphetamine, phenylpropanolamine can be chemically reduced into amphetamine. Molecularly, phenylpropanolamine is to ephedrine, just as amphetamine is to methamphetamine, and as cathinone is to methcathinone.
Phenylpropanolamine was also used for the illicit synthesis of other stimulant drugs such as phenmetrazine and 4-methylaminorex, and since phenylpropanolamine was withdrawn from use in humans in the early 2000s (although it is still sold for some veterinary applications) it is now much less available, and this in turn has meant that phenmetrazine and 4-methylaminorex have largely disappeared from the illicit market.
Phenylpropanolamine can be made from cathinone.

# Side effects
A scientific study found an increased risk of hemorrhagic stroke in women who used phenylpropanolamine, although it is not clear which isomer is to blame. A study at the Yale University School of Medicine in 1999 had produced similar results.  Reports of cases of hemorrhagic strokes in PPA users had been circulating since the 1970s.
A report from the Dept. of Psychiatry, F. Edward Hebert School of Medicine, Bethesda, Maryland in Pharmacopsychiatry states:

# Legal control
In November 2000, the Food and Drug Administration (FDA) issued a public health advisory against the use of the drug.  In this advisory, the FDA requested that all drug companies discontinue marketing products containing phenylpropanolamine.  The agency estimates that PPA caused between 200 and 500 strokes a year among 18-to-49-year-old users. In 2005 the FDA removed phenylpropanolamine from over-the-counter sale. An item on the agenda of the 2000 Commission on Narcotic Drugs session called for including norephedrine in Table I of United Nations Convention Against Illicit Traffic in Narcotic Drugs and Psychotropic Substances
Because of its potential use in methamphetamine manufacture, it is controlled by the Combat Methamphetamine Epidemic Act of 2005. It is still available for use in dogs.