Everything below concerns Melanotan II. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2026-07-12. Where a claim depends on a specific study, the study is described rather than over-claimed.
Melanotan-2 is a synthetic peptide designed as an analog of alpha-melanocyte-stimulating hormone, a signaling molecule produced in the pituitary and skin. Its structure is a linear chain of seven amino acids that folds into a ring through an internal lactam bridge joining two side chains. The compound is sometimes written as MT-II or MEL-2 in informal and commercial contexts. It belongs to the melanocortin peptide family, a group of short signaling molecules that share a conserved core sequence recognized by melanocortin receptors.
Two structural changes distinguish the synthetic peptide from the natural hormone. A norleucine residue replaces methionine at one position, and a D-configured phenylalanine replaces the natural L-form at another. Both substitutions slow enzymatic breakdown, which extends the molecule's persistence relative to the parent hormone. The lactam bridge further constrains the backbone into a stable conformation. These features are standard design strategies in peptide chemistry and are not unique to this compound; they appear across many research peptides built for improved stability.
Receptor-binding studies classify melanotan II as a non-selective melanocortin agonist. It interacts with MC1R, MC3R, MC4R and MC5R, with reported affinities in the low nanomolar range and no strong subtype preference. Activation of MC1R on dermal melanocytes shifts pigment synthesis toward eumelanin, the dark polymer deposited in melanosomes and transferred to keratinocytes. Because the same peptide engages MC4R in the hypothalamus, it also appears in animal work on food intake and erectile response, which is why it is discussed in both pigment and metabolic research. Which receptor populations dominate after systemic exposure in humans is not fully established.
Published pharmacokinetic information is limited and comes mainly from small studies rather than registrational trials. Plasma half-life is usually described as short, on the order of tens of minutes, followed by rapid tissue distribution and clearance of the intact peptide. Metabolites and low concentrations of parent compound have been reported in urine, a detail relevant to anti-doping and forensic testing. Whether repeated exposure changes receptor sensitivity or clearance over time remains an open question. Values differ noticeably between analytical assays, so published numbers should be read as approximate rather than definitive.
| Property | Value | Notes |
|---|---|---|
| Molecular class | Synthetic cyclic heptapeptide | Analog of alpha-MSH with an internal lactam bridge |
| Molecular weight | Approximately 1024 daltons | Free base value; salt forms differ |
| Appearance | White to off-white powder | Usually supplied as a lyophilized solid |
| Solubility | Freely soluble in water | Poorly soluble in nonpolar solvents |
| Typical storage | −20 °C, dry, protected from light | Repeated freeze-thaw cycles degrade peptides |
Regulatory treatment varies between countries. Several national medicines agencies have classified the peptide as unapproved, and customs authorities in some jurisdictions seize shipments on that basis. A few jurisdictions channel supply through prescription-only frameworks that do not list the substance by name. Because the material circulates mainly through online vendors, composition and purity are rarely verified before sale. Surveys of unapproved peptide products have reported labels that did not match measured content in a substantial fraction of samples.
Melanotan II is a synthetic cyclic heptapeptide analogue of alpha-melanocyte-stimulating hormone, a naturally occurring peptide involved in pigmentation signalling. Its structure substitutes a lactam bridge between side chains to increase stability relative to the native hormone. The compound is also known by the shorthand MT-II and by several non-proprietary synonyms used in research catalogues. It is not an approved therapeutic product in any major jurisdiction; material sold under this name is typically offered as a laboratory reagent rather than as a medicine.
Activity is attributed to agonism at melanocortin receptors, particularly MC1R and MC4R. Activation of MC1R on melanocytes increases melanin synthesis, which underlies the reported tanning effect. MC4R engagement in the central nervous system is linked to appetite suppression and to effects on sexual arousal reported in early clinical studies. Those studies were small and were not designed to establish efficacy or long-term safety. Receptor selectivity among the melanocortin subtypes is not absolute, which complicates attribution of any effect to a single pathway.
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.
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.
== Administration == Piperacillin is not absorbed orally, and must therefore be given by intravenous or intramuscular injection. It has been shown that the bactericidal actions of the drug do not increase with concentrations of piperacillin higher than 4-6× MIC, which means that the drug is concentration-independent in terms of its actions. Piperacillin has instead shown to offer higher bactericidal activity when its concentration remains above the MIC for longer periods of time (50% time above MIC showing the highest activity). This higher activity present in continuous dosing has not been directly linked to clinical outcomes, but however does show promise of lowering possibility of resistance and decreasing mortality. Extending the time of piperacillin-tazobactam infusion allows the drugs to maintain the necessary concentrations needed within the body to prevent bacterial growth, enhancing bactericidal activity. The studies supporting this theory generally administered ~3.375 g of piperacillin-tazobactam every 8 hours during a 4-hour infusion, while for organisms with higher minimum inhibitory concentrations, ~4.5 g of piperacillin-tazobactam was administered every 6 hours during a 3-hour infusion. The recommended doses provided by the BNFC for infants with hospital-acquired infections are 90 mg/kg every 8 hours for infants, a maximum of 4.5 g every 6 hours for children, and 4.5 g every 8 hours for children aged 12 and above. A dosage of 90 mg/kg every 6 hours is suggested for infants and children diagnosed with neutropenia.
== Variations and related drinks == Calvados and applejack are strong liquors distilled from cider. They differ in their geographical origin and their method of distillation. Calvados is made throughout Normandy, not just in the Calvados département. It is made from cider by double distillation. In the first pass, the result is a liquid containing 28–30% alcohol. After the second pass, the concentration of alcohol is about 40%. Applejack is a strong alcoholic beverage made in North America by concentrating cider, either by the traditional method of freeze distillation or by true evaporative distillation. In traditional freeze distillation, a barrel of cider is left outside during the winter. When the temperature is low enough, the water in the cider starts to freeze. If the ice is removed, the (now more concentrated) alcoholic solution is left behind in the barrel. If the process is repeated often enough, and the temperature is low enough, the alcohol concentration is raised to 20–30% alcohol by volume. Home production of applejack is popular in Europe. Ice cider (French: cidre de glace), originating in Quebec and inspired by ice wine, has become a Canadian speciality, now also being produced in England. For this product, the apples are frozen either before or after being harvested. Its alcohol concentration is 9–13% ABV. Cidre de glace is considered a local speciality in Quebec and can fetch high prices on the international market. In Canada, ice cider is produced by natural, outdoor freezing.
Nancy's bottom-half finish proved a false dawn as the club finished 18th in the 1985–86 season, which meant they had to win a play-off match to avoid relegation. They retained their league status with a 3–2 aggregate win against Mulhouse. The club however sold several of their best players to avoid financial predicament and provided Wenger with little funds to work with. In Wenger's final season in charge, Nancy finished 19th and were relegated to Ligue 2. Despite the setbacks, he was contacted by Monaco over their vacant managerial job. Talks had begun during the summer of 1986, but Nancy chairman Gérard Rousselot refused to release Wenger from his contract, and Monaco were not prepared to offer compensation. Once Nancy's relegation was confirmed, Wenger was permitted to leave the club by mutual consent and was confirmed as Monaco manager in 1987. Before joining Monaco, Wenger had identified several players to build his desired team. Tottenham Hotspur midfielder Glenn Hoddle, granted a free transfer, and Patrick Battiston, out of contract at Bordeaux, were signed. Striker Mark Hateley left Milan to join Monaco and was "encouraged to learn" that his fellow Englishman Hoddle would play in the same side as him. Monaco won the league in Wenger's debut season, six points ahead of runners-up Bordeaux. Although the team scored more goals in 1988–89 due to the purchase of Liberian striker George Weah, Monaco failed to retain the league and finished third behind Marseille and Paris Saint-Germain.
The Yugoslavia national football team represented Yugoslavia in international association football. Although the team mainly represented the pre-war Kingdom of Yugoslavia and the post-war SFR Yugoslavia, various iterations of the state were formally constituted in football, including the:
Sources: en.wikipedia.org
== Target == It seems likely that TsPep2 has inhibitory actions on potassium channels, based on its sequence similarities in the C-terminal beta sheet with the potassium channel inhibitory alpha family (α-KTX) and on its similarities in the patterns of disulfide bridges with other short scorpion venom toxins.
Portugal's main import markets in 2026 were Spain at 32.9% and Germany at 11.9%. Portugal's main imports are machinery and mechanical appliances, chemical products, agricultural products, and mineral fuels. Since the 1990s, Portugal's economic model has been based on public consumption and economic development focused on exports, private investment and the development of its high-tech sector. Consequently, business services have overtaken more traditional industries such as wine and cork in export earnings. Operated by the Euronext Lisbon, Portugal's stock market, the PSI, includes 16 major companies based on the country, including Sonae, Mota-Engil, Corticeira Amorim, The Navigator Company, and EDP. In 2025, Portugal ranked 16th among European Union member states in innovation by the European Innovation Scoreboard, while placing 31st worldwide in the Global Innovation Index. In 2024, neuroscience accounted for 12.5% of Portugal's scientific output, the second-highest national share, and the country ranked 23rd worldwide in total neuroscience output. Among the research institutions based in the country are the Gulbenkian Institute of Molecular Medicine, the International Iberian Nanotechnology Laboratory, and the Champalimaud Foundation which was the world's 11th top non-profit institution in neuroscience research between 2019 and 2023.
Various authorities (e.g. ITIS 16, GRIN 27, WCSP, NCBI, DELTA) differ on the exact number of genera included in Liliaceae s.s., but generally there are about fifteen to sixteen genera, depending on whether or not Amana is included in Tulipa and Lloydia in Gagea. Currently the APWeb lists fifteen genera, arranged as shown in this table:
fixation 1. (histology) The preservation of biological material by treating it with a chemical fixative that prevents or delays the natural postmortem processes of decay (e.g. autolysis and putrefaction) which would otherwise eventually cause cells, tissues, and biomolecules to lose their characteristic structures and properties. Biological specimens are usually fixed with the broad objective of arresting or slowing biochemical reactions for long enough to study them in detail, essentially 'freezing' cellular processes in their natural state at a specific point in time, while minimizing disruption to existing structures and arrangements, all of which can improve subsequent staining and microscopy of the fixed samples. Though fixation tends to irreversibly terminate any ongoing reactions, thus killing the fixed cells, it makes it possible to study molecular details that occur too rapidly or transiently to observe in living samples. Common fixatives such as formaldehyde work by disabling proteolytic enzymes, coagulating, insolubilizing, and/or denaturing macromolecules, creating crosslinks between them, and protecting specimens from decomposition by bacteria and fungi. 2. (population genetics) The process by which a single allele for a particular gene with multiple different alleles increases in frequency in a given population such that it becomes permanently established as the only allele at that locus within the population's gene pool.
CASP, which stands for Critical Assessment of Techniques for Protein Structure Prediction, is a community-wide experiment for protein structure prediction taking place every two years since 1994. CASP provides with an opportunity to assess the quality of available human, non-automated methodology (human category) and automatic servers for protein structure prediction (server category, introduced in the CASP7). The CAMEO3D Continuous Automated Model EvaluatiOn Server evaluates automated protein structure prediction servers on a weekly basis using blind predictions for newly release protein structures. CAMEO publishes the results on its website.
Sources: en.wikipedia.org
{\displaystyle -{\frac {\mathrm {d} p}{\mathrm {d} x}}={\frac {8\mu Q}{\pi R^{4}}}={\frac {8\mu Q_{2}p_{2}}{\pi pR^{4}}}\quad \Rightarrow \quad -p{\frac {\mathrm {d} p}{\mathrm {d} x}}={\frac {8\mu Q_{2}p_{2}}{\pi R^{4}}}.}
=== Evolution of plant morphology === Transcription factors and transcriptional regulatory networks play key roles in plant morphogenesis and their evolution. During plant landing, many novel transcription factor families emerged and are preferentially wired into the networks of multicellular development, reproduction, and organ development, contributing to more complex morphogenesis of land plants.
The checking and assessment of data during the period of time between trial completion (the last observation on the last subject) and the breaking of the blind, for the purpose of finalising the planned analysis. (ICH E9) Blinded study
=== North America === Soybeans were first introduced to North America from China in 1765, by Samuel Bowen, a former East India Company sailor who had visited China in conjunction with James Flint, the first Englishman legally permitted by the Chinese authorities to learn Chinese. The first "New World" soybean crop was grown on Skidaway Island, Georgia, in 1765 by Henry Yonge from seeds given him by Samuel Bowen. Bowen grew soy near Savannah, Georgia, possibly using funds from Flint, and made soy sauce for sale to England. Although soybean was introduced into North America in 1765, for the next 155 years, the crop was grown primarily for forage. In 1831, the first soy product "a few dozen India Soy" [sauce] arrived in Canada. Soybeans were probably first cultivated in Canada by 1855, and definitely in 1895 at Ontario Agricultural College. It was not until Lafayette Mendel and Thomas Burr Osborne showed that the nutritional value of soybean seeds could be increased by cooking, moisture or heat, that soy went from a farm animal feed to a human food. William Joseph Morse is considered the "father" of modern soybean agriculture in America. In 1910, he and Charles Piper began to popularize what was regarded as a relatively unknown Oriental peasant crop in America into a "golden bean", with the soybean becoming one of America's largest and most nutritious farm crops.
colorimeter Also chromometer. Any instrument used for color measurement based on optical comparison with standard colors, particularly a device used in colorimetry that measures the absorbance of specific wavelengths of light by a given solution in order to determine the concentration of a known solute in the solution, by application of the principle that solute concentration is directly proportional to absorbance.
Sources: en.wikipedia.org
It is a synthetic seven-amino-acid peptide modeled on alpha-melanocyte-stimulating hormone. It carries two non-natural substitutions and a cyclic bridge that increase its stability relative to the natural hormone. It circulates as a research chemical and is not an approved medicine.
Melanotan-1, also called afamelanotide, is a shorter linear analog with a different amino acid sequence and no lactam ring. It has been evaluated in formal clinical programs, while melanotan-2 has not. The two are distinct molecules and are not interchangeable.
No. Bremelanotide is a related but distinct cyclic peptide that reached approved status for one specific clinical indication. Melanotan-2 is a separate molecule with its own sequence and properties. Shared ancestry in the melanocortin family does not make them the same substance.
No. It is a synthetic analogue carrying four amino acid changes, a lactam ring and an amidated C-terminus. The natural hormone is a linear thirteen-amino-acid peptide processed from proopiomelanocortin.