This is a working overview of prohibited list, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2025-10-27. Anything still debated is marked as such rather than presented as settled.
Melanotan-2 is a synthetic linear peptide built from seven amino acids arranged in a short chain. Its sequence is commonly written as Ac-Nle-Asp-His-D-Phe-Arg-Trp-Lys-NH2, which includes a modified N-terminus and an amidated C-terminus. The molecule belongs to the melanocortin family and acts as a receptor agonist. Structural features such as the D-phenylalanine residue and the Nle substitution are associated with increased stability against enzymatic degradation relative to the natural parent peptide.
The compound emerged from research programs in the 1980s that examined analogues of alpha-melanocyte-stimulating hormone for pigmentation and photoprotection. Investigators modified the native sequence to extend activity duration and potency. A related analogue, afamelanotide, was developed within the same broad line of inquiry and eventually gained approval in certain jurisdictions for a rare light-sensitivity condition. Melanotan-2 itself did not progress through the same regulatory route and has no approved therapeutic indication.
Melanocortin receptors comprise five subtypes with distinct tissue distributions and functions. Melanotan-2 is described in the literature as a non-selective agonist that engages several of these subtypes, including MC1R, MC3R, MC4R, and MC5R. MC1R is the subtype most directly linked to melanin production in skin cells. Because the compound is not subtype-selective, its observed effects in experimental settings are generally attributed to activity across multiple receptor pathways rather than to a single target.
Identity and purity are usually assessed by reversed-phase high-performance liquid chromatography, which separates the target peptide from truncated or oxidised impurities. Mass spectrometry, most often coupled to liquid chromatography, confirms molecular mass and detects substitutions that chromatography alone may miss. Amino acid analysis and peptide mapping supply additional structural evidence, while nuclear magnetic resonance is reserved for full structural confirmation. Laboratories that examine samples sold online report wide variation in actual content, with some vials containing little or none of the labelled material.
Melanotan-2 appears on the World Anti-Doping Agency prohibited list within the peptide hormone class, and several national regulators treat it as an unapproved prescription substance. Some countries restrict importation or sale for personal use. Because the compound is widely traded as a research chemical, the practical legal picture differs between jurisdictions and shifts over time. Human safety data covering long periods are limited, and whether repeated pigmentation changes carry any lasting risk to melanocytes remains an open question.
Freeze-dried melanotan-2 is normally kept as a desiccated powder at minus twenty degrees Celsius or lower, shielded from light and moisture. Peptides of this size degrade through hydrolysis, oxidation and deamidation, and each pathway accelerates as temperature and water activity rise. Repeated freeze-thaw cycles promote aggregation and loss of material, so aliquoting a stock solution before freezing is standard laboratory practice. Once dissolved, the solution is markedly less stable than the powder. In laboratory work, solutions are generally refrigerated and used within days rather than kept for months.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C50H69N15O9 | Free base; salt forms differ |
| Molecular weight | Approximately 1024 g/mol | Calculated for the free base |
| Appearance | White to off-white powder | Typically supplied as a lyophilised solid |
| Solubility | Soluble in water and polar solvents | Poorly soluble in non-polar solvents |
| Typical storage | -20 degrees Celsius, dry, protected from light | Refers to the solid form |
Human data remain limited and mostly short-term. Reports describe small trials and observational accounts rather than large controlled studies, so questions about dose-response relationships and long-term effects on melanocytes stay open. Whether repeated exposure alters naevus behaviour is not settled in the published record. Researchers also note that self-administered use outside clinical settings makes actual exposure difficult to quantify. Statements about efficacy and safety should therefore be read as preliminary rather than established.
Melanotan II is a synthetic cyclic heptapeptide that acts as an agonist at melanocortin receptors. It was designed as a structural analogue of alpha-melanocyte-stimulating hormone, the endogenous peptide involved in pigment production. The analogue carries a lactam bridge that constrains the ring and slows enzymatic breakdown relative to the native hormone. In research literature it appears under several abbreviations, and naming conventions are not fully standardized. Published descriptions usually place it within the broader melanocortin agonist family.
Receptor binding at MC1R on melanocytes raises intracellular cyclic AMP and increases expression of tyrosinase and related enzymes. The downstream result is greater synthesis of eumelanin, the dark pigment, without ultraviolet exposure acting as the trigger. The compound is not selective, however, and also engages MC3R, MC4R and MC5R, which are expressed in the central nervous system and elsewhere. That lack of selectivity is the explanation usually offered for effects reported outside pigmentation, including appetite suppression and nausea. Selectivity remains a central theme in comparative studies of related peptides.
Solid peptide kept dry at minus twenty degrees Celsius, shielded from light and moisture, is generally considered stable for extended periods. Solutions are divided into single-use aliquots and held at minus twenty or minus eighty degrees Celsius, because repeated freeze-thaw cycles promote aggregation and loss of material to container surfaces. Hydrolysis of the backbone and oxidation of tryptophan are the principal degradation routes in aqueous solution, and both accelerate at ambient temperature. Hygroscopic uptake after a vial is opened can also shift the actual mass weighed, which affects any concentration calculated from it.
Routine characterisation relies on reversed-phase high-performance liquid chromatography with ultraviolet detection near 214 nanometres, using a C18 column and a water-acetonitrile gradient containing trifluoroacetic acid. Electrospray ionisation mass spectrometry confirms the expected molecular mass and can reveal truncated or oxidised by-products that co-elute poorly. Sequence and stereochemistry require additional work, such as peptide mapping or amino acid analysis, because a chromatographic purity figure alone does not distinguish a diastereomer from the target peptide. Independent testing of research-grade material frequently shows measured content below the stated label, so a certificate of analysis is best read together with the method that produced it.
It is a five-track album featuring two extended multi-chapter songs, "The Necromancer" and "The Fountain of Lamneth". Some critics said Caress of Steel was unfocused and an audacious move for the band because of the placement of two back-to-back protracted songs, as well as a heavier reliance on atmospherics and storytelling, a large deviation from Fly by Night. Intended to be their breakthrough album, Caress of Steel sold below expectations. The tour consisted of smaller venues and declining box office receipts, which led to it being nicknamed the Down the Tubes Tour.
Additionally, the relative (and quantitative) success of the shock therapies, despite the considerable risks they posed to patients, also helped to inspire doctors in the field to pioneer ever more drastic forms of medical interventions, including lobotomies. The clinician-historian Joel Braslow argues that from malarial therapy onward to lobotomy, physical psychiatric therapies "spiral closer and closer to the interior of the brain", with this organ increasingly taking "center stage as a source of disease and site of cure". For medical historian Roy Porter, the often violent and invasive psychiatric interventions developed during the 1930s and 1940s are indicative of both the well-intentioned desire of psychiatrists to find some medical means of alleviating the suffering of the vast number of patients then in psychiatric hospitals and also the relative lack of social power of those same patients to resist the increasingly radical and even reckless interventions of asylum doctors. Many doctors, patients, and family members of the period believed that, despite potentially catastrophic consequences, the results of lobotomy were seemingly positive in many instances or were at least deemed as such when measured next to the apparent alternative of long-term institutionalisation. Lobotomy has always been controversial, but for a period of the medical mainstream, it was regarded as a legitimate last-resort remedy for categories of patients who were otherwise regarded as hopeless.
Other A communicating vein directly connects two parts of the same system such as the Giacomini vein that connects the (superficial) small saphenous vein with the (superficial) great saphenous vein. Peripheral veins carry blood from the limbs and hands and feet.
Zearalenone (ZEN), also known as RAL and F-2 mycotoxin, is a potent estrogenic metabolite produced by some Fusarium and Gibberella species. Specifically, the Gibberella zeae, the fungal species where zearalenone was initially detected, in its asexual/anamorph stage is known as Fusarium graminearum. Several Fusarium species produce toxic substances of considerable concern to livestock and poultry producers, namely deoxynivalenol, T-2 toxin, HT-2 toxin, diacetoxyscirpenol (DAS) and zearalenone. Particularly, ZEN is produced by Fusarium graminearum, Fusarium culmorum, Fusarium cerealis, Fusarium equiseti, Fusarium verticillioides, and Fusarium incarnatum. Zearalenone is the primary toxin that binds to estrogen receptors, causing infertility, abortion or other breeding problems, especially in swine. Often, ZEN is detected together with deoxynivalenol in contaminated samples and its toxicity needs to be considered in combination with the presence of other toxins. Zearalenone is heat-stable and is found worldwide in a number of cereal crops, such as maize, barley, oats, wheat, rice, and sorghum. Its production increases when the climate is warm with air humidity at or above twenty percent. The environmental pH plays also a role in the toxin's production. When temperatures fall to 15 °C, alkaline soils still support ZEN production. At the preferred Fusarium temperature, which ranges between 25 °C and 30 °C, neutral pH results in the greatest toxin production.
Sources: en.wikipedia.org
(Newton's second law of motion in the non-relativistic case, i.e. valid only at ion velocity much lower than the speed of light). Here F is the force applied to the ion, m is the mass of the ion, a is the acceleration, Q is the ion charge, E is the electric field, and v × B is the vector cross product of the ion velocity and the magnetic field Equating the above expressions for the force applied to the ion yields:
An yttrium–barium cuprate, YBa2Cu3O7−x (or Y123), was the first superconductor found above liquid nitrogen boiling point. The three different metals in the YBa2Cu3O7 superconductor are in the mole ratio of 1 to 2 to 3 for yttrium to barium to copper, respectively; hence, this particular superconductor has often been referred to as the 123 superconductor. The unit cell of YBa2Cu3O7 consists of three perovskite unit cells, which is pseudocubic, nearly orthorhombic. The other superconducting cuprates have another structure: they have a tetragonal cell. Each perovskite cell contains a Y or Ba atom at the center: Ba in the bottom unit cell, Y in the middle one, and Ba in the top unit cell. Thus, Y and Ba are stacked in the sequence [Ba–Y–Ba] along the c-axis. All corner sites of the unit cell are occupied by Cu, which has two different coordinations, Cu(1) and Cu(2), with respect to oxygen. There are four possible crystallographic sites for oxygen: O(1), O(2), O(3) and O(4). The coordination polyhedra of Y and Ba with respect to oxygen are different. The tripling of the perovskite unit cell leads to nine oxygen atoms, whereas YBa2Cu3O7 has seven oxygen atoms and, therefore, is referred to as an oxygen-deficient perovskite structure. The structure has a stacking of different layers: (CuO)(BaO)(CuO2)(Y)(CuO2)(BaO)(CuO). One of the key feature of the unit cell of YBa2Cu3O7−x (YBCO) is the presence of two layers of CuO2. The role of the Y plane is to serve as a spacer between two CuO2 planes. In YBCO, the Cu–O chains are known to play an important role for superconductivity.
The toxicity of metal carbonyls is a function of both the toxicity of the metal and the off-gassing of carbon monoxide from the carbonyl functional groups; nickel carbonyl is also explosive in air. Sensitized persons may show a skin contact allergy to nickel known as a contact dermatitis. Highly sensitized persons may also react to foods with high nickel content. Patients with pompholyx may also be sensitive to nickel. Nickel is the top confirmed contact allergen worldwide, partly due to its use in jewelry for pierced ears. Nickel allergies affecting pierced ears are often marked by itchy, red skin. Many earrings are now made without nickel or with low-release nickel to address this problem. The amount allowed in products that contact human skin is now regulated by the European Union. In 2002, researchers found that the nickel released by 1 and 2 euro coins, far exceeded those standards. This is believed to be due to a galvanic reaction. Nickel was voted Allergen of the Year in 2008 by the American Contact Dermatitis Society. In August 2015, the American Academy of Dermatology adopted a position statement on the safety of nickel: "Estimates suggest that contact dermatitis, which includes nickel sensitization, accounts for approximately $1.918 billion and affects nearly 72.29 million people." Reports show that both the nickel-induced activation of hypoxia-inducible factor (HIF-1) and the up-regulation of hypoxia-inducible genes are caused by depletion of intracellular ascorbate.
=== New Zealand in 1998 === In 1998 he walked from Cape Reinga in the North Island, to Bluff, at the southern tip of New Zealand; a distance of 1,500 miles (2,400 km). On the journey he walked through the active volcano at White Island, experienced earthquakes up to 4.9 on the Richter Scale, clambered over glaciers, swam with seals and reported on conservation biology projects involving endangered species. Information from the journey was posted on the Internet for schoolchildren in the U.S. via the Scholastic Corporation Scholastic Network. In December 2010 Skinner completed a book about the journey and conservation biology, New Zealand – 1500 miles on foot through – The Land of the Long White Cloud on an Internet website. In 1999 he obtained a PGCE (Postgraduate Certificate in Education) from Canterbury Christ Church University in Canterbury, England. In 2000 he worked as a secondary school science teacher at St. Edmund's School in Dover, teaching 11 to 16-year-olds. In 2001 he worked as a volunteer at a wildlife park, working on enrichment activities for animals. From 2001 until 2003 he worked part-time at a post office. During this time, he also taught science to primary school children, in a 'Link-Scientist' scheme run by the pharmaceutical company Pfizer, and took care of his son. In 2003 his mother died from pancreatic cancer, at the age of 59. This prompted him to write the story of the 6,000 miles (9,700 km) journey across Britain and America.
== Applications == Ion exchange is widely used in the food and beverage industry, hydrometallurgy, metals finishing, chemical, petrochemical, pharmaceutical technology, sugar and sweetener production, ground- and potable-water treatment, nuclear, softening, industrial water treatment, semiconductor, power, and many other industries. A typical example of application is preparation of high-purity water for power engineering, electronic and nuclear industries; i.e. polymeric or inorganic insoluble ion exchangers are widely used for water softening, water purification, water decontamination, etc. Ion exchange is a method widely used in household filters to produce soft water for the benefit of laundry detergents, soaps, and water heaters. This is accomplished by exchanging divalent cations (such as calcium Ca2+ and magnesium Mg2+) with highly soluble monovalent cations (e.g., Na+ or H+) (see water softening). Another application for ion exchange in domestic water treatment is the removal of nitrate and natural organic matter. In domestic filtration systems ion exchange is one of the alternatives for water softening in households along with reverse osmosis (RO) membranes. Compared to RO membranes, ion exchange requires repetitive regeneration when inlet water is hard (has high mineral content). Industrial and analytical ion-exchange chromatography is another area to be mentioned. Ion-exchange chromatography is a chromatographical method that is widely used for chemical analysis and separation of ions.
Sources: en.wikipedia.org
Volunteer Piper, Commemorative events in Greece. For services to Commemorations and Veterans in Greece. Brenda Patricia Heather-Latu. British Honorary Consul, Apia, Samoa. For services to British Nationals in Samoa. Robert Charles Jackson Hicks. Surgical Team Lead, Hernia International Carpenter and Ghana Healthcare Partners, Leyaata Hospital, Ghana; Consultant Surgeon, Northampton General Hospital. For Services to Health in Northern Ghana. Gregory John Holland. Chief Executive Officer, British Chamber of Commerce, Santiago, Chile. For services to UK/Chile Bilateral Trade and Investment. Daren Hughes. Team Leader, Foreign, Commonwealth and Development Office. For services to British Foreign Policy. Dr. Brad James Irwin. Head of Global Engagement, Natural History Museum. For services to UK Culture and the Arts. Paula Mary Jack. Justice Adviser, Northern Ireland Co-operation Overseas. For services to Child Justice Reform, to Human Rights and to International Relations in Bahrain. Ivor Cosimo Jencks. Lately General Manager, Hongkong Land Group and Head of Commercial Development, Commercial Property, South Asia. For services to Business, to Charity and to Sustainable Development in Vietnam. Jennifer Anne Tudor Larby. Executive Officer, British Legion Kenya. For services to the British and Commonwealth ex-services community in Kenya. Dr. Matthew Linkie. Regional Technical Director, Wildlife Conservation Society. For services to Biodiversity Conservation in Indonesia. Michael Ralph Lubbock.
=== 1971-2000 === In 1971, Revlon acquired DCL BioMedical, a clinical laboratory business founded in 1968. In 1974, it changed its name to National Health Laboratories Incorporated. By 1977, it operated clinical testing laboratories in 13 cities and maintained auxiliary service centers and satellite laboratories in 15 other cities. In 1978, it acquired American Biomedical Corporation, giving it operations in the Southwestern United States and data processing technology. In 1985, Revlon was acquired by Ronald Perelman. Revlon divested its other businesses and a major stake in the company was acquired by MacAndrews & Forbes. In 1988, National Health Laboratories became a public company via an initial public offering on the NASDAQ exchange. In 1989, the company generated revenue of about US$400 million, with about US$70 million in earnings. In the early 1990s, worries about malpractice lawsuits led doctors to conduct more clinical testing before diagnosing, which increased business for the company. In 1990, the company's revenues reached US$500 million, with over US$70 million in earnings. In 1991, National Health Laboratories moved its listing from the NASDAQ to the New York Stock Exchange. In June 1992, the company offered to acquire Damon Corporation for $260 million in cash and stock. However, the company was outbid by Corning Inc., which acquired Damon for $370 million. By 1993, the company had 22 major laboratories. On March 8, 1994, National Health Laboratories Inc. reorganized as a holding company, National Health Laboratories Holdings Inc.
== Solid-phase peptide synthesis (SPPS) == Solid-phase synthesis is a common technique for peptide synthesis. Usually, peptides are synthesised from the carbonyl group side (C-terminus) to amino group side (N-terminus) of the amino acid chain in the SPPS method, although peptides are biologically synthesised in the opposite direction in cells. In peptide synthesis, an amino-protected amino acid is bound to a solid phase material or resin (most commonly, low cross-linked polystyrene beads), forming a covalent bond between the carbonyl group and the resin, most often an amido or an ester bond. Then the amino group is deprotected and reacted with the carbonyl group of the next N-protected amino acid. The solid phase now bears a dipeptide. This cycle is repeated to form the desired peptide chain. After all reactions are complete, the synthesised peptide is cleaved from the bead. The protecting groups for the amino groups mostly used in the peptide synthesis are 9-fluorenylmethyloxycarbonyl group (Fmoc) and t-butyloxycarbonyl (Boc). A number of amino acids bear functional groups in the side chain which must be protected specifically from reacting with the incoming N-protected amino acids. In contrast to Boc and Fmoc groups, these have to be stable over the course of peptide synthesis although they are also removed during the final deprotection of peptides.
Amitriptyline, formerly sold under the brand name Elavil among others, is a tricyclic antidepressant primarily used to treat major depressive disorder, and a variety of pain syndromes such as neuropathic pain, fibromyalgia, migraine and tension headaches. Due to the frequency and prominence of side effects, amitriptyline is generally considered a second-line therapy for these indications. The most common side effects are dry mouth, drowsiness, dizziness, constipation, and weight gain. Glaucoma, liver toxicity and abnormal heart rhythms are rare but serious side effects. Blood levels of amitriptyline vary significantly from one person to another, and amitriptyline interacts with many other medications potentially aggravating its side effects. Amitriptyline was discovered in the late 1950s by scientists at Merck and approved by the US Food and Drug Administration (FDA) in 1961. It is on the World Health Organization's List of Essential Medicines. It is available as a generic medication. In 2023, it was the 90th most commonly prescribed medication in the United States, with more than 7 million prescriptions.
Sources: en.wikipedia.org
No. Melanotan-2 is manufactured synthetically. The naturally occurring peptide in the same family is alpha-melanocyte-stimulating hormone, which the body produces as part of normal endocrine and neural signalling.
Both are synthetic analogues derived from the same parent hormone. Reference descriptions usually characterise afamelanotide as more selective for the MC1R subtype, whereas melanotan-2 is reported to interact with a wider range of melanocortin receptors.
Early studies explored melanocortin signalling and pigmentation, which later led to informal use of the label tanning peptide. That label is not a regulatory category and does not imply approved status for any purpose.
The lyophilised solid is best kept cold, dry and dark, typically at minus twenty degrees Celsius. Moisture and repeated warming cycles are the main causes of degradation. Solutions prepared from the powder are less stable and are normally used quickly.