Everything below concerns melanocortin. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2026-07-31. Numbers and descriptions here follow the published literature rather than marketing material.
Melanotan-2 is frequently confused with afamelanotide, a linear analogue authorised in the European Union for erythropoietic protoporphyria. The two compounds differ in chain length, ring structure and receptor selectivity, so findings for one cannot be transferred directly to the other. Published controlled human data on melanotan-2 remain sparse, and much of what circulates online derives from small studies or unpublished reports. Questions about effect size, dose-response behaviour and long-term safety therefore remain unresolved.
Melanotan-2 is a synthetic cyclic heptapeptide designed as an analogue of alpha-melanocyte-stimulating hormone. Its sequence incorporates a lactam bridge that constrains the peptide into a ring, which increases resistance to enzymatic breakdown relative to the natural hormone. Researchers at the University of Arizona synthesised the compound in the late 1980s and early 1990s while studying pigmentation pathways. It has never received marketing approval from any national medicines regulator. In the scientific literature it is usually described as a laboratory research reagent rather than a therapeutic product.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic cyclic heptapeptide | Alpha-MSH analogue with a lactam ring |
| Molecular formula | C50H69N15O9 | Commonly cited value for the neutral peptide |
| Molecular weight | 1024.18 g/mol | Calculated for the free molecule |
| Appearance | White to off-white powder | Typically supplied as a lyophilised solid |
| Solubility | Soluble in water, DMSO and ethanol | Dissolution in pure water is often slow |
The compound was developed in the late 1980s and early 1990s by academic researchers investigating melanocortin signaling and pigmentation. Early work explored whether synthetic analogs could reproduce effects of the natural hormone under controlled conditions. The molecule never advanced through the full regulatory pathway required for approval as a medicine. From the mid-2000s onward it appeared in unregulated consumer markets, often distributed through informal channels. That gap between research origins and commercial availability shapes how the compound is discussed today.
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.
Early published reports described melanotan-2 as a tanning agent without sun protection, which means darkening is not the same as protection against ultraviolet radiation. Later studies explored the peptide in erectile dysfunction, hemorrhagic shock, and some skin conditions. No regulator in the United States or Europe has approved it for clinical use. Many products labelled melanotan-2 are sold without approval and their identity and purity are unverified. Its long-term safety in humans remains an open question.
Melanotan-2, also written Melanotan II, is a synthetic cyclic heptapeptide designed as an analogue of alpha-melanocyte-stimulating hormone. Its sequence is Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH2, and the lactam bridge between the aspartate and lysine side chains constrains the peptide into a ring. This structural change increases receptor affinity and metabolic stability relative to the native hormone. The compound was created in the 1980s as a research tool for studying pigmentation biology.
Shortly after the 7 October attacks and Israel's retaliation in October 2023, preventable diseases were expected to rise due to disruption in vaccination abilities. Childhood vaccinations had already dropped due to the COVID-19 pandemic, and experts cautioned about the spread of infectious diseases such as COVID-19 and measles that could be contained primarily with vaccinations. In mid-December 2023, the Gaza Health Ministry stated it had run out of vaccinations for children, which would have catastrophic repercussions. An UNOCHA representative stated the organization was having difficulty delivering childhood vaccines. On 1 January 2024 it was reported by the Palestinian Health Ministry that Israel had allowed and would facilitate the transport of vaccines into Gaza through the Rafa crossing. It was cautioned that the disbursement of the vaccines would be difficult due to displacement and destruction of infrastructure. On 29 January 2024, UNICEF reported that 16,000 children were at risk of missing routine vaccinations. In July 2024, a polio outbreak occurred in Gaza, marking the first appearance of the virus there in 25 years, and it remains ongoing. In order to contain the polio virus outbreak and limit further transmission, the WHO held two vaccination drives, one in September 2024 that reached 90% of children under 10, and one in February 2025.
Durston had attempted to treat Travers with salivation, which he believed reduced her breasts slightly but which she did not like as a treatment option, and then cauterization followed by incision by knife in the hope that excess fluid would be found to drain, but this was unsuccessful as it was healthy breast tissue, notable only for its massive enlargement and thus lacking excess fluid to drain.
==== Ketamine ==== Research on the antidepressant effects of ketamine infusions at subanaesthetic doses has consistently shown rapid (4 to 72 hours) responses from single doses, with substantial improvement in mood in the majority of patients and remission in some. However, these effects are often short-lived, and attempts to prolong the antidepressant effect with repeated doses and extended ("maintenance") treatment have resulted in only modest success. A nasal spray formulation of esketamine, sold under the brand name Spravato, gained FDA approval in 2019 for the treatment of treatment-resistant depression when combined with an oral antidepressant. Evidence-based meta-analyses support treatment protocols that differ substantially from standard real-world clinical practice: an optimized dose of 0.71 mg/kg rather than the conventional 0.5 mg/kg, intravenous infusion rather than intranasal delivery, and a racemic formulation rather than esketamine alone.
As the poisoning progresses, the muscular twitching becomes more pronounced and convulsions suddenly appear in all the skeletal muscles. The limbs are extended and the neck is curved to opisthotonus. The pupils are widely dilated. As death approaches, the convulsions follow one another with increased rapidity, severity, and duration. Death results from asphyxia due to prolonged paralysis of the respiratory muscles. Following the ingestion of strychnine, symptoms of poisoning usually appear within 15 to 60 minutes.
Sources: en.wikipedia.org
=== Dependency === Adrenal suppression will begin to occur if prednisone is taken for longer than seven days. Eventually, this may cause the body to temporarily lose the ability to manufacture natural corticosteroids (especially cortisol), which results in dependence on prednisone. For this reason, prednisone should not be abruptly stopped if taken for more than seven days; instead, the dosage should be gradually reduced. This weaning process may be over a few days if the course of prednisone is short but may take weeks or months if the patient had been on long-term treatment. Abrupt withdrawal may lead to an Addisonian crisis. For those on chronic therapy, alternate-day dosing may preserve adrenal function and thereby reduce side effects. Glucocorticoids act to inhibit feedback of both the hypothalamus, decreasing corticotropin-releasing hormone (CRH), and corticotrophs in the anterior pituitary gland, decreasing the amount of adrenocorticotropic hormone (ACTH). For this reason, glucocorticoid analogue drugs such as prednisone down-regulate the natural synthesis of glucocorticoids. This mechanism leads to dependence in a short time and can be dangerous if medications are withdrawn too quickly. The body must have time to begin synthesis of CRH and ACTH and for the adrenal glands to begin functioning normally again. Prednisone may start to result in the suppression of the hypothalamic–pituitary–adrenal (HPA) axis if used at doses 7–10 mg or higher for several weeks. This is approximately equal to the amount of endogenous cortisol produced by the body every day.
==== Political franchise ==== The principal ideological disagreement Socialist Studies has with the SPGB is its attitude towards attempts by workers living under political dictatorships to establish elementary democratic and trade union rights, especially in Eastern Europe in the 1980s and early 1990s. The stance of the SPGB since 1939 is summarised by the following 1990 party conference resolution:This Conference re-affirms the stand taken in the September [actually October] 1939 Socialist Standard and repeated in the September 1989 Socialist Standard, that the Socialist Party of Great Britain wholeheartedly supports the efforts of workers everywhere to secure democratic rights against the powers of suppression. Whilst we avoid any association with parties or political groups seeking to administer capitalism, we emphasise that freedom of movement and expression, the freedom to organise in trade unions, to organise politically, and to participate in elections, are of great importance to all workers and are vital to the success of the socialist movement. On the other hand, Socialist Studies regards the struggle by workers living under a dictatorship to establish some measure of political democracy as a reformist struggle which socialists should oppose. They believe that the difference between democratic capitalist governments and dictatorial capitalist governments is of no significance to workers, that political democracy is not essential for the propagation of socialist ideas and that workers in dictatorships should not directly confront the forces of suppression.
According to the 2011 census, the literacy rate in Jammu and Kashmir was 67.17%, male literacy was 75%, while female literacy was at 56.43%. University of Kashmir located in Srinagar is the main university in the territory. Other universities include University of Jammu, Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir, Shri Mata Vaishno Devi University, Islamic University of Science & Technology, etc. Major institutions of higher education are NIT Srinagar, IIT Jammu, IIM Jammu, NIFT Srinagar and IHM Srinagar. Medical colleges include SKIMS, and the Government Medical College in Srinagar and All India Institute of Medical Sciences, Vijaypur, Jammu.
Mariculture is the cultivation of marine organisms in seawater, variously in sheltered coastal waters ("inshore"), open ocean ("offshore"), and on land ("onshore"). Farmed species include algae (from microalgae (such as phytoplankton) to macroalgae (such as seaweed); shellfish (such as shrimp), lobster, oysters), and clams, and marine finfish. Channel catfish (Ictalurus punctatus), hard clams (Mercenaria mercenaria) and Atlantic salmon (Salmo salar) are prominent in the U.S. mariculture. Mariculture may consist of raising the organisms on or in artificial enclosures such as in floating netted enclosures for salmon, and on racks or in floating cages for oysters. In the case of enclosed salmon, they are fed by the operators; oysters on racks filter feed on naturally available food. Abalone have been farmed on an artificial reef consuming seaweed which grows naturally on the reef units.
=== Canonical signaling: The SMAD pathway === Smads are a class of intracellular signalling proteins and transcription factors for the TGF-β family of signalling molecules. This pathway conceptually resembles the Jak-STAT signal transduction pathway characterized in the activation of cytokine receptors implicated, for example, in the B cell isotype switching pathway. As previously stated, the binding of the TGF-β ligand to the TGF-β receptor, the type 2 receptor kinase phosphorylates and activates the type 1 receptor kinase that activates a signaling cascade. In the case of Smad, receptor-activated Smads are phosphorylated by the type 1 TGF-β receptor kinase, and these go on to complex with other Smads, which is able to translocate into the cell nucleus to induce transcription of different effectors. More specifically, activated TGF-β complexes bind to the type 2 domain of the TGF-β receptor which then recruits and phosphorylates a type 1 receptor. The type 1 receptor then recruits and phosphorylates a receptor regulated SMAD (R-SMAD). The R-SMAD then binds to the common SMAD (coSMAD) SMAD4 and forms a heterodimeric complex. This complex then enters the cell nucleus where it acts as a transcription factor for various genes, including those to activate the mitogen-activated protein kinase 8 pathway, which triggers apoptosis. The SMAD pathway is regulated by feedback inhibition. SMAD6 and SMAD7 may block type I receptors.
Sources: en.wikipedia.org
== Rheumatism, excluding the back (725–729) == 725 Polymyalgia rheumatica 726 Peripheral enthesopathies and allied syndromes 726.0 Adhesive capsulitis, shoulder 726.1 Rotator cuff syndrome, NOS (Not Otherwise Specified) 726.12 Bicipital tenosynovitis 726.3 Enthesopathy of elbow region 726.31 Medial epicondylitis 726.32 Lateral epicondylitis 726.33 Olecranon bursitis 726.4 Enthesopathy of wrist and carpus 726.5 Enthesopathy of hip region 726.6 Enthesopathy of knee 726.61 Pes anserinus tendinitis 726.64 Tendinitis, patellar 726.65 Prepatellar bursitis 726.7 Metatarsalgia, NOS (Not Otherwise Specified) 726.71 Tendinitis, achilles 726.72 Tendinitis, tibialis 726.73 Calcaneal spur 727 Other disorders of synovium, tendon and bursa 727.0 Synovitis and tenosynovitis 727.00 Synovitis/tenosynovitis, unspec. 727.03 Trigger finger, acquired 727.04 de Quervain's disease 727.05 Tenosynovitis, hand/wrist 727.06 Tenosynovitis, foot/ankle 727.1 Bunion 727.4 Ganglion and cyst of synovium, tendon, and bursa 727.42 Ganglion, tendon sheath 727.43 Ganglion, unspec.
Sub-ppb (parts per billion) levels of silica make it equally complex for both reactive and total silica analysis, making the choice of total silica test often preferred. Although particles and TOC are usually measured using on-line methods, there is significant value in complementary or alternative off-line lab analysis. The value of the lab analysis has two aspects: cost and speciation. Smaller UPW facilities that cannot afford to purchase on-line instrumentation often choose off-line testing. TOC can be measured in the grab sample at a concentration as low as 5 ppb, using the same technique employed for the on-line analysis (see on-line method description). This detection level covers the majority of needs of less critical electronic and all pharmaceutical applications. When speciation of the organics is required for troubleshooting or design purposes, liquid chromatography-organic carbon detection (LC-OCD) provides an effective analysis. This method allows for identification of biopolymers, humics, low molecular weight acids and neutrals, and more, while characterizing nearly 100% of the organic composition in UPW with sub-ppb level of TOC. Similar to TOC, SEM particle analysis represents a lower cost alternative to the expensive online measurements and therefore it is commonly a method of choice in less critical applications. SEM analysis can provide particle counting for particle size down to 50 nm, which generally is in-line with the capability of online instruments.
Xi called for a crackdown on corruption immediately after he ascended to power, starting an anti-corruption campaign. In his inaugural speech as general secretary, Xi mentioned that fighting corruption was one of the toughest challenges for the party. A few months into his term, Xi outlined the Eight-point Regulation, listing rules intended to curb corruption and waste during official party business; it aimed at stricter discipline on the conduct of officials. Xi vowed to root out "tigers and flies", that is, high-ranking officials and ordinary party functionaries. He also launched the Party's Mass Line Education and Practice Activities, aiming CCP cadres to use mass line and instill Party discipline. The campaign lasted from 2013 to 2014. Xi's anti-corruption campaign has led to the downfall of prominent incumbent and retired CCP officials, including members of the PSC. Xi initiated cases against former CMC vice chairmen Xu Caihou and Guo Boxiong, former PSC member and security chief Zhou Yongkang and former CCP General Office director Ling Jihua. Xi has overseen significant reforms of the Central Commission for Discipline Inspection (CCDI), CCP's highest internal control institution. He and CCDI Secretary Wang Qishan further institutionalized CCDI's independence from the day-to-day operations of the CCP, improving its ability to function as a bona fide control body. Along with Wang Qishan, Xi's administration spearheaded the formation of "centrally-dispatched inspection teams".
== External links == American Association of Bioanalysts AAB Associate Member Section American Board of Bioanalysis College of Reproductive Biology Environmental Biology and Public Health Section National Independent Laboratory Association
DNA templated synthesis of combinatorial libraries described in 2001 by Gartner et al. Dual pharmacophore DNA encoded combinatorial libraries invented in 2004 by Mlecco et al. Sequence encoded routing published by Harbury Halpin and Harbury in 2004. Single pharmacophore DNA encoded combinatorial libraries introduced in 2008 by Manocci et al. DNA encoded combinatorial libraries formed by using yoctoliter-scale reactor published by Hansen et al. in 2009 Details are found about their synthesis and application in the page DNA-encoded chemical library. The DNA encoded soluble combinatorial libraries have drawbacks, too. First of all the advantage coming from the use of solid support is completely lost. In addition, the polyionic character of DNA encoding chains limits the utility of non-aqueous solvents in the synthesis. For this reason many laboratories choose to develop DNA compatible reactions for use in the synthesis of DECLs. Quite a few of available ones are already described
Sources: en.wikipedia.org
It is a synthetic cyclic heptapeptide modelled on alpha-melanocyte-stimulating hormone. A lactam bridge links two side chains, forming a ring that stabilises the molecule against proteolysis. It belongs to the broader melanocortin peptide family.
No national medicines agency has approved melanotan-2 for clinical use. Afamelanotide, a related but distinct peptide, holds a marketing authorisation in the European Union for a rare photosensitivity disorder. Melanotan-2 itself is handled as a laboratory chemical.
Its broad activity across melanocortin receptors makes it a tool for probing pigmentation, appetite and vascular signalling. Early trials recorded skin darkening and other effects that were not the original focus of the work. Those observations generated hypotheses that later studies have examined.
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.