This is a working overview of melanocortin signalling, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-05-29 and is reviewed periodically as new material appears.
Identity and purity of semax are established with reversed-phase high-performance liquid chromatography coupled to ultraviolet detection, usually at 214 nanometres. Mass spectrometry, most often electrospray ionisation in positive mode, confirms the molecular mass and reveals truncated sequences. Amino acid analysis and peptide mapping after enzymatic digestion provide additional structural confirmation. Laboratories typically report purity as the percentage area of the main peak, a figure that does not capture isomeric or oxidised variants unless the method resolves them.
The peptide is prone to several degradation pathways. Oxidation of the methionine residue produces a sulfoxide that elutes close to the parent peak in many chromatographic systems. Hydrolysis of peptide bonds and deamidation of susceptible residues in related sequences also reduce purity over time. Lyophilised material kept dry at minus twenty degrees Celsius and shielded from light is the most stable form commonly described in laboratory practice.
Semax 是一种人工合成的七肽，氨基酸序列为 Met-Glu-His-Phe-Pro-Gly-Pro，单字母缩写记作 MEHFPGP。它被归类为促肾上腺皮质激素片段 ACTH(4-10) 的结构类似物，但并不天然存在于生物体内。母体片段 ACTH(4-10) 的序列为 Met-Glu-His-Phe-Arg-Trp-Gly，Semax 替换了中间两个残基，并在羧基端延长了 Pro-Gly-Pro 三肽。这种延长被普遍认为能提升分子对肽酶的耐受性。
该化合物于二十世纪八十年代在俄罗斯被开发，相关工作由俄罗斯科学院分子遗传学研究所的研究团队主导。开发目标并非复制 ACTH 的完整激素活性，而是寻找保留其神经作用方向、同时去除促肾上腺皮质激素释放效应的短肽片段。研究记录显示，这一方向促成了多个相关短肽的合成与筛选，而 Semax 是其中被研究最广泛的一个。当地文献常以 Семакс 这一名称指代它。
| Property | Value | Notes |
|---|---|---|
| Appearance | White to off-white powder | Lyophilised solid |
| Solubility class | Freely soluble in water | Also dissolves in aqueous buffers |
| Typical storage temperature | -20 °C | Dry, desiccated, protected from light |
| Typical analytical method | RP-HPLC with UV detection | Often paired with LC-MS |
| Water content | Reported as Karl Fischer value | Freeze-dried material is hygroscopic |
Published studies examine a fairly narrow set of endpoints. Rodent experiments commonly measure maze learning, infarct volume after induced ischemia, and tissue levels of neurotrophic factors. Clinical reports from Russian centres describe attention, memory and recovery scores in patients after stroke or transient ischemic attack. Most of those human studies are small and few have been repeated by independent groups. Outcome measures differ between studies, which limits direct comparison.
Circulation time for the peptide is short because peptidases cleave it readily. The Pro-Gly-Pro tail is thought to slow breakdown compared with the bare ACTH fragment, but the gain appears modest. Absorption after intranasal dosing is limited, and only a fraction of a dose is expected to reach the central nervous system. Laboratory concentrations therefore sit well above levels achieved systemically, a gap that complicates translation from bench findings to clinical claims.
Clinical reports describe use in ischaemic stroke, transient ischaemic attack, optic nerve conditions, and cognitive complaints, but most of these studies are small and were conducted in a single region. Systematic reviews have generally described the evidence base as limited in size and variable in methodological quality. Randomised controlled data suitable for international regulatory assessment are scarce. As a result, major treatment guidelines outside Russia do not include the peptide, and interest in it remains largely research-driven rather than routine clinical.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It is described in the literature as an analogue of the ACTH(4–10) fragment, a short N-terminal portion of adrenocorticotropic hormone that retains some neurotropic activity without the full hormonal effects of the parent peptide. The molecule carries a methionine residue at the N-terminus and two proline residues near the C-terminus, features that shape both its interactions with receptor systems and its chemical stability. The free peptide corresponds to the formula C37H51N9O10S and a molecular mass near 813.9 Da.
The compound was developed in the 1980s at the Institute of Molecular Genetics in Moscow, where it emerged from research on short ACTH fragments and their effects on the central nervous system. Russian pharmaceutical listings describe it as a nootropic and neuroprotective agent, most often formulated as nasal drops. It is not a marketed medicine in the United States or the European Union, and no pharmacopoeial monograph covers it. Consequently, most published clinical experience with the substance originates from a small number of research centres, mainly in Russia and neighbouring countries.
Silica monoliths, on the other hand, are created in a mold, undergo a significant amount of shrinkage, and are then clad in a polymeric shrink tubing like PEEK (polyetheretherketone) to reduce wall effects. This method limits the size of columns that can be produced to less than 15 cm long, and though standard analytical inner diameters are readily achieved, there is currently a trend in developing nanoscale capillary and prep scale silica monoliths.
6 August Weather Forecast about weather forecasting in the UK; Swedish Lennart Bengtsson of the European Centre for Medium-Range Weather Forecasts; Alistair Woodroffe and Brian Webster of the Met Office; numerical calculations began in the early 1950s with computers making 10,000 calculations a second but by the mid-1980s it was one billion; Meteosat-2 launched in June 1981; Steven Burke of the London Potato Futures Association; Capt Derek Ralph in a British Caledonian BAC One-Eleven flying to Aberdeen Airport; amateur weatherman Bill Foggitt; the weather centre and Lockheed C-5 Galaxy aircraft at RAF Mildenhall; conservationist Robin Page; narrated by Muriel Gray, directed by John Dollar, made by Uden Associates 13 August Made to Measure, essentially a re-edited, slightly updated edition of the August 1986 episodes on the F1 Ford turbocharged engine, with a few minutes of new content; in May 1987 Peter Collins watches the previous San Marino Grand Prix; Ford Cosworth V6 B187 cars: engine mapping; Dick Scammel, general head of engineering; Martin Walters, chief development engineer; the engine is dismantled, and damage is found; Geoff Goddard, chief racing engine designer; electromagnetic pulses from the engine affected the working of the engine computer circuitry; rogue signals were picked up by the engine computer, so causing erratic fuel injection; French F1 driver Patrick Tambay listens to the sound of the turbo; the turbo pressure would be limited to 2.5 in 1988, before turbos were banned for the 1989 season; the Italian Grand Prix circuit; each team is allowed two sets of qualifying tyres; the tyres on the rear axle warm up before the front axle; the Honda V6 engine could produce 1200 hp; chief designer Rory Byrne, and F1 aerodynamic forces. Narrated mostly by Martin Jarvis and partly by Eleanor Bron 20 August Twang, Bang, Kerang!, about the electric guitar; the Fat Tuesdays night club, and Les Paul; Glenn Wilson of the Institute of Psychiatry in London; Louis Jordan in the late 1940s; Charlie Christian developed the Gibson-ES150; Steve Howe of Yes; Burns London manufacturing guitars; Dave Russell; the body of the guitar was made of maple, a tonewood, and the fretboard of rosewood; the sound originates from the type of wood; Jerry Donohue of Fairport Convention; pickups made by Seymour Duncan; Chet Atkins; Andy Summers of The Police and Every Breath You Take; Francis Dunnery of It Bites, and Once Around the World. Narrated by John Hedges, produced by Patrick Uden, directed by Jeremy Llewellyn-Jones, made by Uden Associates 27 August What Goes Up..., about dismantling the AGR at Sellafield; it featured Tom Marsham CBE FRS (10 November 1923 – 12 October 1989) of UKAEA at Risley, Warrington (Birchwood Park), who was the reactor manager of Calder Hall in 1956. Narrated by Sue Jay, produced by Michael Blakstad, made by Workhouse Productions 3 September Hole in the Sky, about the depletion of the ozone layer, with Sir Bob Watson at NASA; the NERC's British Antarctic Survey had been measuring ozone levels since 1957 at the Halley Research Station, and a team led by Joe Farman noticed a hole in the layer; NASA had not noticed an ozone hole on its Nimbus 7 satellite, although the satellite had picked up all of the data, as Richard Stolarski of the Goddard Space Flight Center found; the ozone hole was caused by the polar vortex over the winter, where air movements outside of Antarctica are trapped, and there is not enough light to form new ozone; some people believed that the 1982 Mexican El Chichón volcanic eruption was to blame; in 1974 F. Sherwood Rowland and Mario Molina of the University of California, Irvine found that some chlorine compounds would destroy ozone by making chlorine monoxide, and both received the 1995 Nobel Prize in Chemistry for this discovery; the Chemical Manufacturers' Association (since 2000 the American Chemistry Council) and the National Science Foundation launched a new atmospheric survey at McMurdo Station, led by Susan Solomon of the Earth System Research Laboratories; Jerry D. Mahlman of the Geophysical Fluid Dynamics Laboratory at Princeton was attempting a computer model of the Antarctic atmosphere; Rafe Pomerance of the World Resources Institute; the greenhouse effect, described by James Hansen of the Goddard Institute for Space Studies, who claimed that the Earth's temperature would be 2 degrees higher by 2000, 3 degrees higher by 2010, and 4 to 7 degrees warmer by 2030; Richard E. Benedick. Directed by Linda Harrar, produced by Paula Apsell, made by WGBH, Uden Associates, Television Trust for the Environment and Sveriges Television. Originally a Nova documentary 24 September Dirty Money, about whether the environment can be cleaned up; the UK's first anti-pollution trade fair in March 1987, attended by William Waldegrave; Father Jim Conlon and Portglenone Abbey in N Ireland, with an anaerobic digester, which saved £1000 a month in gas cost, and the manure was sold for £25,000 a year; Mike Flux of ICI; biologist Paul Johnston of Greenpeace, in Teesside; the River Tees was the second-most polluted in the UK, with Douglas Ord of Northumbrian Water; Ken Murphy, and how Greenpeace attempted to block an effluent pipe near Immingham in March 1985; John Elkington, environmental writer; BioTechnica of Llanishen in Cardiff, reclaiming contaminated land on a former highly polluted gasworks site in Lancashire; Jutta Ditfurth; Hans-Georg Peine of BASF AG, and the Sandoz chemical spill in November 1986 in Switzerland; in 1983, ICI founded the first bioplastic company, called Marlborough Biopolymers, which made polyhydroxy butyrate; Dame Anita Roddick of The Body Shop, who worked with Friends of the Earth; Peter Baylis of the NERC Environmental Satellite Laboratory, which began in 1975, in the University of Dundee's Ewing Building, and largely provided the only UK archive of satellite environmental data. Narrated by Bob Peck, produced by Edward Poulter, directed by David Sharp, made by London Scientific Films 1 October Malltime. A US production, produced by Mike Wallington, made by George Haggerty, made by Kai Productions 8 October Anything You Can Do..., about new robotics; the five houses puzzle; Richard Gregory, professor of neuropsychology at the University of Bristol; Roger Mathias of Plessey Radar and the Multi-function Electronically Scanned Adaptive Radar (MESAR), began in 1982; Henry Thompson and speech recognition at the School of Informatics, University of Edinburgh; Robert Kowalski of the Department of Computing, Imperial College London; Margaret Boden of the University of Sussex; J. Michael Brady; Paul Caplin and robotics; Roy Bottomley of Meiko Scientific, and the transputer, developed in the UK; Plessey Laboratories at the Allen Clark Research Centre, and new chemical compounds for computer chip; logic programming and heuristics; the European Eureka Prometheus Project, an expert system. Narrated by Miriam Margolyes, produced by Michael Blakstad, directed by Catherine Robins, made by Workhouse Productions 22 October Command and Control, the chain of command of nuclear weapons; it featured the Air Force Research Laboratory. Directed by Clive Syddall, made by Twenty Twenty Vision 5 November Earthquake Country, about the San Andreas fault; Robert Wallace, chief scientist of the USGS; the 1906 earthquake caused the tectonic planes to move around seven metres; geologist Grove Karl Gilbert; an earthquake in the middle section of the fault was expected for around 1988; a 5.8 earthquake on 8 June 1934; geologist Kerry Sieh and paleoseismology; if an earthquake took place, coordination would be from the Joint Forces Training Base - Los Alamitos; earthquake engineer George W. Housner of Caltech; structural engineer Ray William Clough; earthquake engineer Luis Estava Maraboto of the Engineering Institute of the National Autonomous University of Mexico. Produced by Arabella Woods, directed by John Tchalenko, made by Red Rooster Films 12 November Nature's Technology, about the different types and the modelling of animal locomotion, and legged robots; robotic hands and bioengineer Stephen Jacobsen of the University of Utah; snake-arm robots; the 1986 Adaptive Suspension Vehicle (ASV) of Ohio State University, a hexapod robot, and Vincent Vohnout; active balance and Marc Raibert; the 1965 Walking Truck of General Electric; static stability and the Odex 1 six-legged robot; biomechanics and Robert McNeill Alexander, Professor of Zoology; WABOT-2 of Waseda University, optical music recognition and the NHK Symphony Orchestra of Japan conducted by Yuzo Toyama. Narrated by Adrienne Posta, directed by David Barlow, produced by Karl Sabbagh, made by InCA 19 November Britain Can Make It?, about making kitchen units in the UK and in Germany; the dual system of apprenticeship in Germany; Sig Prais of the National Institute of Economic and Social Research; the Britain Can Make It exhibition, where the fitted kitchen was first introduced in the UK; the Hungarian designer George Fejer was largely responsible for introducing fitted kitchens; Wolfgang Luckhaus of Poggenpohl of Germany, which also developed the fitted kitchen; in the 1960s the Germans introduced chipboard for kitchen manufacturing, which became industry-standard, with wipe-clean melamine resin facing (MFC); Hilary Steedman of the NIESR, and how the Germans built kitchens to order, whereas British companies simply built kitchens, whether ordered or not; Heal's of London introduced German kitchens to the UK in the early 1970s, in a hausfest; the German SieMatic kitchen company; Doug Gregory started The Symphony Group in 1970 after seeing chipboard, developing flatpack kitchen units, the Germans did not make flatpack kitchens, only assembled kitchens; David Love, buying director of MFI, which was helped by the flatpack revolution, but it was all largely an imitation of German products, and was a mostly standard product range; Symphony introduced computer production control in the 1980s, which the Germans had introduced in the early 1970s - this allowed much more variation of manufacturing to order, which was the main German method; employees of Symphony were largely unskilled, but German workers were largely skilled apprentices, who had passed exams in manufacturing; nearly all of German kitchens were built to order, so needed skilled workers; Walter Siekmann, production manager of Poggenpohl; German furniture manufacture was found in East Westphalia (Ostwestfalen); the Germans believed in more thorough technical training, and sold their products all over the world, but British companies had less-thorough training, and did not sell as worldwide as the Germans. Narrated by John Woodvine, directed by David Habakkuk, made by Riverside Television 26 November At the Edge, about the physical limits placed upon fighter pilots when flying high G capable modern aircraft, such as the F16 and the F18. Pilots are subjected to G-LOC in the Aerospace Medicine centrifuge in San Antonio, Texas. Narrated by Ray Brooks, written, produced and directed by Chris Haws, made by InCA
== Applications == Neuropeptides and antagonists that bind to their receptors can be used as insecticides. These include both naturally occurring neuropeptides and synthetic compounds designed to block their receptors. In humans, neuropeptides have been implicated in several human diseases. Antagonists to the related receptors may have clinical application.
Sources: en.wikipedia.org
=== Natural occurrence === Earth has retained all of the noble gases that were present at its formation except helium. Krypton's concentration in the atmosphere is about 1 ppm. It can be extracted from liquid air by fractional distillation. The amount of krypton in space is uncertain, because measurement is derived from meteoric activity and solar winds. The first measurements suggest an abundance of krypton in space.
==== Canada ==== In October 2018, cannabidiol became legal for recreational and medical use by the federal Cannabis Act. As of August 2019, CBD products in Canada could only be sold by authorized retailers or federally licensed medical companies, limiting their access to the general public. Nonetheless, with online delivery services and over 2,600 authorized cannabis retail stores as of October 2021, accessibility has steadily increased over time. The Canadian government states that CBD products "are subject to all of the rules and requirements that apply to cannabis under the Cannabis Act and its regulations." It requires "a processing licence to manufacture products containing CBD for sale, no matter what the source of the CBD is, and that CBD and products containing CBD, such as cannabis oil, may only be sold by an authorized retailer or licensed seller of medical CBD." Edible CBD products were scheduled to be permitted for sale in Canada on October 17, 2019, for human consumption. As of August 2020, it was still illegal to carry cannabis and cannabis-derived products (including products containing CBD) across the Canadian border. If one carries any amount of cannabis for any purpose (including medical), it needs to be declared to the Canada Border Services Agency. Not declaring it is a serious criminal offence.
Hughes Helicopters was renamed McDonnell Douglas Helicopter Systems later in August 1984. Although the direct link with Hughes was broken, the helicopter designs created by Hughes Helicopters would continue to be produced by Boeing Rotorcraft Systems, MD Helicopters, and Schweizer RSG.
== Prospects == Global wild fisheries are in decline, with valuable habitat such as estuaries in critical condition. The aquaculture or farming of piscivorous fish, like salmon, does not help the problem because they need to eat products from other fish, such as fish meal and fish oil. Studies have shown that salmon farming has major negative impacts on wild salmon, as well as the forage fish that need to be caught to feed them. Fish that are higher on the food chain are less efficient sources of food energy. Apart from fish and shrimp, some aquaculture undertakings, such as seaweed and filter-feeding bivalve molluscs like oysters, clams, mussels and scallops, are relatively benign and even environmentally restorative. Filter-feeders filter pollutants as well as nutrients from the water, improving water quality. Seaweeds extract nutrients such as inorganic nitrogen and phosphorus directly from the water, and filter-feeding mollusks can extract nutrients as they feed on particulates, such as phytoplankton and detritus. Some profitable aquaculture cooperatives promote sustainable practices. New methods lessen the risk of biological and chemical pollution through minimizing fish stress, fallowing netpens, and applying integrated pest management. Vaccines are being used more and more to reduce antibiotic use for disease control. Onshore recirculating aquaculture systems, facilities using polyculture techniques, and properly sited facilities (for example, offshore areas with strong currents) are examples of ways to manage negative environmental effects.
Sources: en.wikipedia.org
In 1991, the Proceeds of Crime (Money Laundering) Act was brought into force in Canada to give legal effect to the former FATF Forty Recommendations by establishing record keeping and client identification requirements in the financial sector to facilitate the investigation and prosecution of money laundering offences under the Criminal Code and the Controlled Drugs and Substances Act. In 2000, the Proceeds of Crime (Money Laundering) Act was amended to expand the scope of its application and to establish a financial intelligence unit with national control over money laundering, namely FINTRAC. In December 2001, the scope of the Proceeds of Crime (Money Laundering) Act was again expanded by amendments enacted under the Anti-Terrorism Act with the objective of deterring terrorist activity by cutting off sources and channels of funding used by terrorists in response to 9/11. The Proceeds of Crime (Money Laundering) Act was renamed the Proceeds of Crime (Money Laundering) and Terrorist Financing Act. In December 2006, the Proceeds of Crime (Money Laundering) and Terrorist Financing Act was further amended, in part, in response to pressure from the FATF for Canada to tighten its money laundering and financing of terrorism legislation.
On 15 September 2024, Bukele stated that his 2025 government budget would not include "a single cent of debt for current spending" ("solo centavo de deuda para gasto corriente") and that his government would not take out foreign loans to pay for the budget. On 16 October, El Salvador and J.P. Morgan & Co. agreed to restructure US$1.03 billion of the country's debt as a part of a debt-for-nature swap, which Bukele described as "reaffirm[ing] this government's commitment to economic growth". In the agreement, El Salvador would allocate US$352 million in savings towards conserving the environment around the Lempa River. On three occasions in 2024, Bukele offered to buy back billions of dollars worth of government bonds due by 2034. In November 2024, the Central American Bank for Economic Integration announced that it would give the Salvadoran government $646 million to finance infrastructure projects. Bukele stated that the bank's support would help El Salvador's "economic takeoff" ("despegue económico"). Later that month, Bukele wrote on X that he supported mining gold, describing it as "wealth that could transform El Salvador". He further described the country's metal mining ban as "absurd". The Catholic Church, which supported the mining ban's implementation in 2017, called on Bukele to not repeal the ban, citing environmental concerns. The Legislative Assembly repealed the ban on 23 December 2024 and Bukele approved the law that same day.
Harkin responded by elevating OAM into an independent NIH "center", just short of being its own "institute", and renamed it the National Center for Complementary and Alternative Medicine (NCCAM). NCCAM had a mandate to promote a more rigorous and scientific approach to the study of alternative medicine, research training and career development, outreach, and "integration". Stephen Strauss was the director of NCCAM from 1999 to 2006. He tried to bring more scientific rigor to the organization. In 1999 the NCCAM budget was increased from $20 million to $50 million. The United States Congress approved the appropriations without dissent. In 2000, the budget was increased to about $68 million, in 2001 to $90 million, in 2002 to $104 million, and in 2003, to $113 million.
In Taiwan, the Taiwan Transportation Safety Board (TTSB) is the independent government agency that is responsible for major transportation accident investigations. TTSB's predecessor was ASC, which was established in 1998. TTSB is under the administration of the Executive Yuan and independent from Civil Aviation Administration. The TTSB consisted of five to seven board members, including a chairman and a vice chairman, appointed by the Premier. The managing director of TTSB manages the day-to-day function of the organization, including accident investigations. In the United Kingdom, the agency responsible for investigation of civilian air crashes is the Air Accidents Investigation Branch (AAIB) of the Department for Transport. Its purpose is to establish the circumstances and causes of the accident and to make recommendations for their future avoidance.
Anthony Tiran Todd (December 4, 1954 – November 6, 2024) was an American actor. Known for his distinctly deep and gravelly voice, he amassed numerous credits on screen and in video games since the 1980s, including the title character in the Candyman film series (1992–2021) and William Bludworth in the Final Destination franchise (2000–2025). For the former, he was nominated at the Critics' Choice and Fangoria Chainsaw Awards. Todd's films include Platoon (1986), Night of the Living Dead (1990), The Crow (1994), The Rock (1996), Wishmaster (1997), Hatchet, Minotaur (both 2006), The Man from Earth (2007), Frankenstein (2015), Death House (2017), and Hell Fest (2018). On television, he played Kurn in Star Trek: The Next Generation (1990–1991) and Star Trek: Deep Space Nine (1996), Lord Haikon on Stargate SG-1 (2005–2006), and appeared in the MTV series Scream (2019) and Devil May Cry (2025). Todd was a prolific voice actor, notably voicing the Vortigaunts in the Half-Life series of games, the Fallen in Michael Bay's Transformers: Revenge of the Fallen (2009), Zoom in The Flash (2014–2023), Darkseid in the DC Animated Movie Universe (2015–2020), Venom in the video game Marvel's Spider-Man 2 (2023), and Locus in the video game Indiana Jones and the Great Circle (2024). For Spider-Man 2, he received a British Academy Games Award nomination.
Sources: en.wikipedia.org
Reversed-phase high-performance liquid chromatography is the standard method, with detection in the ultraviolet range. Peak area percentage yields a purity figure for the main component. Mass spectrometry is normally run alongside to confirm molecular identity.
Dry lyophilised powder is generally kept at minus twenty degrees Celsius, protected from light and moisture. Repeated freeze-thaw cycles are avoided because they encourage aggregation and moisture uptake. Solutions are less stable than the solid form and degrade faster at room temperature.
A certificate documents what the supplier measured, not what an independent party confirmed. Methods, instruments and acceptance criteria can differ between suppliers. Third-party testing is the usual way to resolve discrepancies.
不是。Semax 是完全人工合成的七肽，自然界中没有对应的已知肽段。它的设计灵感来自促肾上腺皮质激素片段 ACTH(4-10)，但序列经过了替换和延长。