This is a working overview of melanogenesis, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2025-11-22. Anything still debated is marked as such rather than presented as settled.
Melanotan II binds several melanocortin receptor subtypes rather than a single target. MC1R on melanocytes drives melanin synthesis, while MC3R and MC4R participate in energy balance, appetite, and sexual response pathways. This lack of selectivity explains why reported effects extend beyond skin darkening. Substitutions at positions four and seven, including norleucine and D-phenylalanine, increase potency and resistance to peptidases. Understanding which receptor mediates which effect remains an active area of investigation.
Published human data come mostly from small, short studies rather than large controlled trials. Reported outcomes include increased skin pigmentation and, in some reports, effects on appetite and libido, but sample sizes are small and follow-up is limited. Whether long-term use produces durable pigment changes or adverse effects is not established. Because products sold outside pharmacies are not standardized, the actual content of any given vial is often unknown. Independent testing of such material is uncommon.
Melanotan II is a synthetic cyclic heptapeptide analog derived from the core sequence of alpha-melanocyte-stimulating hormone. Researchers at the University of Arizona synthesized it during the 1980s while studying pigmentation and appetite signaling. The compound is not an approved medicine in any major jurisdiction and appears mainly in laboratory and research-chemical settings. Its structure incorporates a lactam bridge between side chains, which constrains the ring and slows enzymatic breakdown relative to the natural hormone.
Structurally, Melanotan-2 retains the core recognition motif of alpha-melanocyte-stimulating hormone while adding a lactam bridge that links two side chains and constrains the molecule into a ring. This modification lowers susceptibility to enzymatic degradation. The compound acts as an agonist at melanocortin receptors, particularly subtypes associated with melanin production. Because the same receptor family influences several physiological processes, researchers note that its activity is not confined to pigmentation alone. Receptor selectivity continues to be examined in published studies.
Melanotan-2 is a synthetic cyclic heptapeptide designed as an analogue of alpha-melanocyte-stimulating hormone, a naturally occurring peptide involved in pigmentation signalling. Its sequence incorporates modified residues that increase potency and extend biological activity relative to the native hormone. The compound binds receptors of the melanocortin family and is examined mainly in laboratory research. It does not occur naturally and exists only as a manufactured chemical entity produced by solid-phase synthesis.
The peptide was developed during the 1980s by researchers investigating melanocortin signalling and skin pigmentation pathways. Early work focused on analogues of alpha-melanocyte-stimulating hormone that would resist enzymatic breakdown more effectively than the parent molecule. Melanotan-2 emerged from that programme as a shortened, cyclised variant. Reports describing its synthesis and receptor activity later appeared in the scientific literature. Commercial availability grew through unregulated channels rather than through pharmaceutical approval.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic cyclic heptapeptide | Analog of alpha-melanocyte-stimulating hormone |
| Primary receptor family | Melanocortin receptors MC1R through MC5R | Binding is not subtype-selective |
| Development period | 1980s | Synthesized during pigmentation and appetite research |
| Regulatory status | Not an approved medicine | No major regulator has authorized human use |
| Related compound | Afamelanotide | Linear analog studied for photoprotection |
In August 2003, Domino's announced its first new pizza since January 2000, the "Philly Cheese Steak Pizza". The product launch also marked the beginning of a partnership with the National Cattlemen's Beef Association, whose beef Check-Off logo appeared in related advertising. Domino's continued its move toward specialty pizzas in 2006, with the introduction of its "Brooklyn Style Pizza", featuring a thinner crust, cornmeal baked in to add crispness, and larger slices that could be folded in the style of traditional New York-style pizza.In 2008, Domino's once again branched out into non-pizza fare, offering oven-baked sandwiches in four styles, intended to compete with Subway's toasted submarine sandwiches. Early marketing for the sandwiches made varied references to its competition, such as offering free sandwiches to customers named "Jared", a reference to Subway's spokesman of the same name. The company introduced its "American Legends" line of specialty pizzas in 2009, featuring 40% more cheese than the company's regular pizzas, along with a greater variety of toppings. That same year, Domino's began selling its "BreadBowl Pasta" entree, a lightly seasoned bread bowl baked with pasta inside, and the "Lava Crunch Cake" dessert, a crunchy chocolate shell filled with warm fudge. Domino's promoted the dessert by flying in 1,000 cakes to deliver at Hoffstadt Bluffs Visitor Center near Mount St. Helens in Washington state.
=== Inflammatory and immune-related diseases === Microbial therapeutics are being studied for the treatment of inflammatory and immune-related diseases, including inflammatory bowel disease (IBD), allergies, and autoimmune disorders. In these conditions, the immune system becomes overactive or poorly regulated, leading to chronic inflammation. Certain microorganisms can help reduce inflammation by promoting immune balance. For example, some gut microbes produce molecules that calm inflammatory immune responses or support immune cells that help prevent excessive inflammation. Researchers are also developing engineered microorganisms that can release anti-inflammatory substances directly at sites of inflammation, which may reduce side effects compared with treatments that affect the entire body.
In the early post approval period lurasidone-treated patients with bipolar disorder were retrospectively found to have more complex clinical profiles, comorbidities, and prior treatment history compared to patients initiated with other atypical antipsychotics. The study authors suggest this may be due to "the overall clinical profile of lurasidone, the role perceived for lurasidone in the therapeutic armamentarium by practitioners, and the recent introduction of lurasidone into clinical practice during the study period".
=== Gluconeogenesis === Glucagon is traditionally a catabolic hormone, but also stimulates the anabolic process of gluconeogenesis by the liver, and to a lesser extent the kidney cortex and intestines, during starvation to prevent low blood sugar. It is the process of converting pyruvate into glucose. Pyruvate can come from the breakdown of glucose, lactate, amino acids, or glycerol. The gluconeogenesis pathway has many reversible enzymatic processes in common with glycolysis, but it is not the process of glycolysis in reverse. It uses different irreversible enzymes to ensure the overall pathway runs in one direction only.
== Quantum theory == In quantum mechanics, the energy of a quantum system is described by a self-adjoint (or Hermitian) operator called the Hamiltonian, which acts on the Hilbert space (or a space of wave functions) of the system. If the Hamiltonian is a time-independent operator, emergence probability of the measurement result does not change in time over the evolution of the system. Thus the expectation value of energy is also time independent. The local energy conservation in quantum field theory is ensured by the quantum Noether's theorem for the energy-momentum tensor operator. Thus energy is conserved by the normal unitary evolution of a quantum system. However, when the non-unitary Born rule is applied, the system's energy is measured with an energy that can be below or above the expectation value, if the system was not in an energy eigenstate. (For macroscopic systems, this effect is usually too small to measure.) The disposition of this energy gap is not well-understood; most physicists believe that the energy is transferred to or from the macroscopic environment in the course of the measurement process, while others believe that the observable energy is only conserved "on average". No experiment has been confirmed as definitive evidence of violations of the conservation of energy principle in quantum mechanics, but that does not rule out that some newer experiments, as proposed, may find evidence of violations of the conservation of energy principle in quantum mechanics.
Sources: en.wikipedia.org
Commercial airliners typically cruise at altitudes of 9–12 km (30,000–39,000 ft) which is in the lower reaches of the stratosphere in temperate latitudes. This optimizes fuel efficiency, mostly due to the low temperatures encountered near the tropopause and low air density, reducing parasitic drag on the airframe. Stated another way, it allows the airliner to fly faster while maintaining lift equal to the weight of the plane. (The fuel consumption depends on the drag, which is related to the lift by the lift-to-drag ratio.) It also allows the airplane to stay above the turbulent weather of the troposphere. The Concorde aircraft cruised at Mach 2 at about 60,000 ft (18 km), and the SR-71 cruised at Mach 3 at 85,000 ft (26 km), all within the stratosphere. Because the temperature in the tropopause and lower stratosphere is largely constant with increasing altitude, very little convection and its resultant turbulence occurs there. Most turbulence at this altitude is caused by variations in the jet stream and other local wind shears, although areas of significant convective activity (thunderstorms) in the troposphere below may produce turbulence as a result of convective overshoot. On October 24, 2014, Alan Eustace became the record holder for reaching the altitude record for a manned balloon at 135,890 ft (41,419 m). Eustace also broke the world records for vertical speed skydiving, reached with a peak velocity of 1,321 km/h (822 mph) and total freefall distance of 123,414 ft (37,617 m), lasting 4 minutes and 27 seconds.
4-HO-MET, also known as 4-hydroxy-N-methyl-N-ethyltryptamine, as well as metocin or methylcybin, is a psychedelic drug of the tryptamine and 4-hydroxytryptamine families related to psilocin (4-HO-DMT). It is taken orally. The drug acts as a non-selective serotonin receptor agonist, including of the serotonin 5-HT2A receptor. It is a close structural analogue of psilocin (4-HO-DMT) and is the 4-hydroxyl analogue of methylethyltryptamine (MET). 4-HO-MET was discovered by Alexander Shulgin in the 1970s. It was first described in the literature by David Repke and colleagues in 1981. The drug was encountered as a novel recreational and designer drug by 2008. It is openly sold as a legal recreational drug in the United States.
=== Other uses === In developing countries, moringa has the potential to improve nutrition, boost food security, foster rural development, and support sustainable landcare. It may be used as forage for livestock, a micronutrient liquid, a natural anthelmintic, and possible adjuvant. Moringa trees have been used to combat malnutrition, especially among infants and nursing mothers. Since moringa thrives in arid and semiarid environments, it may provide a versatile, nutritious food source throughout the year in various geographic regions. Some 140 organizations worldwide have initiated moringa cultivation programs to lessen malnutrition, purify water, and produce oils for cooking. Moringa oleifera leaf powder was as effective as soap for hand washing when wetted in advance to enable antiseptic and detergent properties from phytochemicals in the leaves. Moringa oleifera seeds and press cake have been implemented as wastewater conditioners for dewatering and drying fecal sludge. Moringa seed cake, obtained as a byproduct of pressing seeds to obtain oil, is used to filter water using flocculation to produce potable water for animals or humans. Moringa seeds contain dimeric cationic proteins, which absorb and neutralize colloidal charges in turbid water, causing the colloidal particles to clump together, making the suspended particles easier to remove as sludge by either settling or filtration. Combination of moringa seed protein, biochar, and sand removes toxicants in water, including E. coli, making the treated drinking water safe by international water quality criteria.
== Waste water produced by resin regeneration == Most ion-exchange systems use columns of ion-exchange resin that are operated on a cyclic basis. During the filtration process, water flows through the resin column until the resin is considered exhausted. That happens only when water leaving the column contains more than the maximal desired concentration of the ions being removed. Resin is then regenerated by sequentially backwashing the resin bed to remove accumulated suspended solids, flushing removed ions from the resin with a concentrated solution of replacement ions, and rinsing the flushing solution from the resin. Production of backwash, flushing, and rinsing wastewater during regeneration of ion-exchange media limits the usefulness of ion exchange for wastewater treatment. Water softeners are usually regenerated with brine containing 10% sodium chloride. Aside from the soluble chloride salts of divalent cations removed from the softened water, softener regeneration wastewater contains the unused 50–70% of the sodium chloride regeneration flushing brine required to reverse ion-exchange resin equilibria. Deionizing resin regeneration with sulfuric acid and sodium hydroxide is approximately 20–40% efficient. Neutralized deionizer regeneration wastewater contains all of the removed ions plus 2.5–5 times their equivalent concentration as sodium sulfate.
Sources: en.wikipedia.org
== Committees == CLSI documents are developed by committees consisting of experts in medical testing or related aspects. Each CLSI committee produces consensus documents related to a specific discipline.
== History == Etifoxine was developed by Hoechst in the 1960s. It was introduced for medical use in France in 1979. Since at least 2000, etifoxine has been marketed by the French pharmaceutical company Biocodex. Following reports of post-marketing toxicity, the safety of etifoxine was reassessed by the French government and the European Medicines Agency (EMA). In January 2022, the EMA "finalized its review of Stresam and concluded that the medicine can continue to be used for the treatment of anxiety disorders, but it must not be used in patients who previously had severe skin reactions or severe liver problems after taking etifoxine."
== Environment == D. dadantii is a pathogen that is spread through water with the splashing of water from infected plants or recycled irrigation water, insects and cultural practices, such as using contaminated tools and machinery or improper storage of vegetables or seeds with infected substances. Insects are an important vector for movement of the pathogen. Insects are able to carry the bacteria externally and internally and are normally unharmed by the bacteria. However, there is continued research in the area of D. dadantii as an insect pathogen to aphids. The pea aphid is able to contract the pathogen from an infected plant and is destroyed in a mode of action similar to Bacillus thuringiensis by producing cyt-like entomotoxins that cause sepsis. The most important factor to disease development is environmental factors consisting of high humidity and temperatures of 71° to 93 °F (22° to 34 °C). In greenhouses, D. dadantii can survive in potting media with or without a host plant for a year or more and in the leaves of host or nonhost plants for 5 to 6 months. It is unable to be pathogenic below 20 °C (68 °F).
Sources: en.wikipedia.org
No regulator in a major market has approved it for human use. It appears in research settings and in products marketed outside pharmacy channels. Legal status for personal possession varies by country.
Afamelanotide is a linear analog that has received approval in some jurisdictions for a specific photoprotection indication. Melanotan II is cyclic and less selective across melanocortin receptors. The two are related but are not interchangeable in regulatory or clinical terms.
A compound that activates several receptor subtypes may produce effects beyond pigmentation. Selectivity influences which tissues respond and shapes the side-effect profile described in reports. Designing subtype-selective analogs is a stated goal of melanocortin research.
It is a synthetic cyclic heptapeptide and an analogue of alpha-melanocyte-stimulating hormone. The molecule is produced by chemical synthesis rather than extracted from a biological source.