If you have been reading about ACTH analog and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Updated 2026-04-25. Numbers and descriptions here follow the published literature rather than marketing material.
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.
Material sold for laboratory use varies widely in stated purity and documentation. A certificate of analysis should list the analytical method, the column and detector used, and the observed purity value. Independent verification by an outside laboratory is the practical way to confirm identity when documentation is absent or internally inconsistent. Regulatory status differs by country, and a product legal in one jurisdiction may be unapproved or controlled in another.
Development took place during the 1980s at institutes of the Russian Academy of Sciences, where peptide fragments of ACTH were screened for cognitive and neuroprotective effects. The compound received regulatory approval in Russia as a nasal preparation, marketed for conditions such as ischemic stroke, transient ischemic attacks, and optic nerve disorders. Registration in other countries has not followed. Most published clinical reports originate from a small number of Russian research groups, and independent replication outside that setting remains limited. The regulatory status therefore differs sharply between Russia and the rest of the world.
Laboratory work points toward modulation of neurotrophic signaling, particularly expression of brain-derived neurotrophic factor and nerve growth factor in hippocampal tissue. Studies also describe effects on monoamine turnover, inflammatory mediators, and oxidative markers. These observations come mainly from animal models and cultured cells, so the causal chain in humans is not firmly established. Whether the reported molecular changes translate into measurable clinical benefit is an open question. Reviews generally present the mechanism as plausible rather than demonstrated.
Clinical evidence consists largely of small trials with modest sample sizes, often without independent replication. Reported endpoints include cognitive scores, recovery after stroke, and visual function, but study designs vary widely and few trials meet contemporary reporting standards. Systematic reviewers have noted a high risk of bias in several of these reports. No large multicenter trial conducted outside Russia has been published. The compound is therefore best described as investigational in most jurisdictions, with its clinical role still unresolved.
| 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 |
Identity and purity are confirmed with reversed-phase high-performance liquid chromatography, typically monitored at 214 nanometres where the peptide bond absorbs. Mass spectrometry, either electrospray or MALDI-TOF, verifies molecular mass against the theoretical value and detects truncation or adduct formation. Amino acid analysis and peptide mapping provide additional confirmation when required. The most frequently reported impurities are deletion sequences from incomplete coupling, methionine sulfoxide from oxidation, and dimeric species formed through non-covalent aggregation. Impurity profiles depend strongly on the synthesis and purification route chosen by the producer.
Published research has focused mainly on neurological and cognitive endpoints in animal models, with proposed mechanisms involving brain-derived neurotrophic factor and related signalling pathways. A substantial share of the human data originates from a limited number of research groups, and independent replication in other countries remains sparse. Regulatory status reflects that distribution: the peptide is registered as a medicine in Russia and appears in some neighbouring markets, while elsewhere it is handled as a research chemical without approved therapeutic labelling. Questions about dose-response relationships, long-term effects, and comparability across studies are still open.
Lyophilised powder is normally kept at -20 °C in a desiccated container, with some suppliers recommending -80 °C for long-term archival storage. Repeated freeze-thaw cycles are the most common cause of avoidable loss, so aliquoting before freezing reduces variability between working sessions. Dissolved peptide is far less stable than the dry solid and is usually prepared fresh or held briefly at 4 °C. Aqueous solutions support both hydrolysis of the backbone and oxidation of the N-terminal methionine, and these two routes dominate degradation under ordinary laboratory conditions.
Later generations of the molecule include an N-acetylated form and an amidated form, both marketed online alongside the parent peptide. These variants differ in terminal chemistry and stability, and they are frequently discussed in the same breath even though they have not been compared in controlled trials. Supply outside formal healthcare systems comes largely from laboratories that synthesize peptides to order. Purity and identity of these materials vary widely, and no single body oversees the international trade.
Semax is a synthetic heptapeptide developed in the Soviet Union during the 1980s by researchers at the Institute of Molecular Genetics in Moscow. It was designed as a truncated analog of adrenocorticotropic hormone, retaining only the fragment spanning residues four through ten. Investigators sought a peptide that would preserve the cognitive effects associated with ACTH while eliminating the hormonal stimulation of the adrenal cortex. The compound entered clinical use in Russia during the following decade.
Russian regulatory authorities approved the peptide for nasal administration, and it remains listed in the national pharmacopoeia under several trade names. Documented indications include acute ischemic stroke, transient ischemic attacks, traumatic brain injury, and certain ophthalmological and neurological conditions. Physicians also prescribe it for cognitive complaints in older patients, although the evidence base for that use is thinner. Outside Russia and a few neighboring states, the substance is not an approved medicine and is sold instead as a research chemical.
== Television == Airwolf Danger Man, (Known as Secret Agent in the United States) I Led Three Lives – The first foray into mass culture dealing with the Cold War. I Spy (1965–68 US television series) Get Smart MacGyver The Man from U.N.C.L.E. Mission: Impossible Quatermass II Several episodes of Star Trek featured a futuristic version of the Cold War, in terms of the United Federation of Planets vs. The Klingon Empire and the Romulan Star Empire, analogs for the United States, the Soviet Union, and the People's Republic of China, respectively. "A Taste of Armageddon" also showed the concept of MAD in a war between opposing sides. Scarecrow and Mrs. King Ivan the Terrible 1976 sitcom The Rocky and Bullwinkle Show 1960s cartoon for children and adults where the villains are Boris and Natasha, who were both parodies of the Soviet spies. The Sandbaggers The Twilight Zone, a number of episodes of which depicted fallout shelters, such as the 1961 episode, The Shelter, produced as a social commentary on the Civil Defense push during the Berlin Crisis of 1961, and the 1987 Ronald Reagan era "Shelter Skelter". Twilight Zone episodes commenting on other aspects of the Cold War, and World Peace include the 1986 A Small Talent for War. The Transformers (TV series), including the fact that the two first seasons take place during the latter years of the Cold War, an episode, Prime Target directly refers to an event of the episode as The highest point of tension between United States and Soviet Union, since the Cuban Missile Crisis.
=== Faith and beliefs === When asked if he believed in God, Freeman said: "It's a hard question because as I said at the start, I think we invented God. So if I believe in God, and I do, it's because I think I'm God." He later said that his experience working on The Story of God with Morgan Freeman did not change his views on religion, further stating that he sees Zoroastrianism being a belief system, that, "is intrinsically me: 'Good thoughts, good words, good deeds' sums it up. How many of us that believe in that?".
== Genome == The genome of T. pallidum was first sequenced in 1998 and revealed a small 1.14 Mbp genome, one of the smallest bacterial genomes. The GC-content is 52.8%. The DNA sequences of T. pallidum species are more than 99.7% identical, and PCR-based assays are effective at differentiating these species. About 92.9% of DNA was determined to be open reading frames, 55% of which had predicted biological functions, while 17% matched hypothetical proteins of unknown function in other organisms and the remainder (28%) did not have significant similarity to other known sequences. The small size of the T. pallidum genome indicates that the species has limited metabolic capabilities, and thus mostly relies on its host for many molecules typically provided by biosynthetic pathways. For instance, it is missing genes encoding key enzymes in oxidative phosphorylation and the tricarboxylic acid cycle. Thus, T. pallidum is no longer able to synthesize fatty acids, nucleic acids, and amino acids, instead relying on its mammalian hosts for these materials. T.pallidum's low levels of diversity within its DNA sequence, forces the pathogen to utilize horizontal gene transfer for genetic diversity, although the specific mechanism is not well understood. It may possibly be a clonal species that still employs recombination. The strains T. pallidum pertenue (TPE) and T.pallidum endemicum (TEN) also experience gene transfer via different subspecies but are notably geographically isolated.
Sources: en.wikipedia.org
This is combined with education, skill development and work training programs. For instance, the Building Bridge to Education program was started in 2014 to provide mentors and skill development classes to youth that are at risk of unemployment. Such active labour market policies have been successful for Denmark in the short-term and the long-term. For example, 80% of participants in the Building Bridge for Education program felt that "the initiative has helped them to move towards completing an education". On a more macro scale, a study of the impact of ALMPs in Denmark between 1995 and 2005 showed that such policies had positive impact not just on employment but also on earnings. The effective compensation rate for unemployed workers has been declining for the last decades, however. Unlike in most Western countries there is no legal minimum wage in Denmark. A relatively large proportion of the population is active on the labour market, not least because of a very high female participation rate. The total participation rate for people aged 15 to 64 years was 78.8% in 2017. This was the 6th-highest number among OECD countries, only surpassed by Iceland, Switzerland, Sweden, New Zealand and the Netherlands. The average for all OECD countries together was 72.1%. According to Eurostat, the unemployment rate was 5.7% in 2017. This places unemployment in Denmark somewhat below the EU average, which was 7.6%. 10 EU member countries had a lower unemployment rate than Denmark in 2017.
The retention factor of the compound of interest should be around 0.2 - 0.3 in order to minimize the time and the amount of eluent to run the chromatography. The other compounds should have retention factors quite different from that of the compount of interest. To pick a good eluent, one run multiple small scale pretests, often using thin layer chromatography (TLC) with the same stationary phase, using solvents of different polarity, until a suitable solvent system is found. Common mobile phase solvents, in order of increasing polarity, include hexane, dichloromethane, ethyl acetate, acetone, and methanol. A common solvent system is hexane:ethyl acetate mixture. The proportions are adjusted so that the target compound has a retention factor of 0.2 - 0.3. Contrary to common misconception, methanol alone can be used as an eluent for highly polar compounds, and does not dissolve silica gel. The eluent flow rate can be optimized. A higher flow rate eluent decreases the time required to run a column and thereby decreases diffusion, improving the resolving power. However, if the flow rate is too high, the analyte would fail to equilibrate between the stationary phase and mobile phase (see Van Deemter's equation). To increase the flow rate of a gravity-flow column chromatography, one can increase the height of the fresh eluent column above the top of the stationary phase, or decrease the tap controls. It can also be increased by using a pump or by using compressed gas (e.g. air, nitrogen, or argon) to push the solvent through the column (flash column chromatography).
== Stages and timeline == Formulation studies include developing a preparation of the drug which is both stable and acceptable to the patients. For orally administered drugs, this usually implies incorporating the drug in a tablet or a capsule. It is important to make the distinction that a tablet contains a variety of other potentially inert substances apart from the drug itself, and studies have to be carried out to ensure that the encapsulated drug is compatible with these other substances in a way that does not cause harm, whether direct or indirect. Preformulation involves the characterization of a drug's physical, chemical, and mechanical properties in order to choose what other ingredients (excipients) should be used in the preparation. In dealing with protein pre-formulation, the important aspect is to understand the solution behavior of a given protein under a variety of stress conditions such as freeze/thaw, temperature, shear stress among others to identify mechanisms of degradation and therefore its mitigation. Formulation studies then consider such factors as particle size, polymorphism, pH, and solubility, as all of these can influence bioavailability and hence the activity of a drug. The drug must be combined with inactive ingredients by a method that ensures that the quantity of drug present is consistent in each dosage unit e.g. each tablet. The dosage should have a uniform appearance, with an acceptable taste, tablet hardness, and capsule disintegration. It is unlikely that formulation studies will be complete by the time clinical trials start.
== Functional protein microarrays == Functional protein microarrays (also known as target protein arrays) are constructed by immobilising large numbers of purified proteins and are used to identify protein–protein, protein–DNA, protein–RNA, protein–phospholipid, and protein–small-molecule interactions, to assay enzymatic activity and to detect antibodies and demonstrate their specificity. They differ from analytical arrays in that functional protein arrays are composed of arrays containing full-length functional proteins or protein domains. These protein chips are used to study the biochemical activities of the entire proteome in a single experiment. The key element in any functional protein microarray-based assay is the arrayed proteins must retain their native structure, such that meaningful functional interactions can take place on the array surface. The advantages of controlling the precise mode of surface attachment through use of an appropriate affinity tag are that the immobilised proteins will have a homogeneous orientation resulting in a higher specific activity and higher signal-to-noise ratio in assays, with less interference from non-specific interactions.
Sources: en.wikipedia.org
==== Early career ==== Townsend joined the Tottenham Hotspur academy at the age of eight. In March 2009, he went on loan to Yeovil Town, making his football league debut against Milton Keynes Dons alongside fellow Spurs academy player Jonathan Obika. He made ten appearances and scored one goal for Yeovil as they avoided relegation.
== Treatment == There is no clearly defined cure for necrobiosis. NLD may be treated with PUVA therapyPhotodynamic therapy and improved therapeutic control. Although some techniques can be used to diminish the signs of necrobiosis, such as low-dose aspirin orally, a steroid cream or injection into the affected area, this process may be effective for only a small percentage of those treated. First medications applied are topical corticosteroids, but these may not be effective for all patients. Compression therapy and proper wound care are essential for treatment. Anti-inflammatory, immunosuppressive, and immunomodulatory agents like chloroquine, dapsone, and oral calcineurin inhibitors. These target the cyclic and damaging immune response occurring in NL. Since TNF is essential to granuloma formation, antibodies that bind to TNF-α to prevent its action help reduce inflammation, pain, and the growth of ulcers. A study found a 70% complete reduction of NL when using TNF-α inhibitors. Hyperbaric oxygen can also be used to increase the amount of oxygen circulation and promote wound healing.
=== Early uses === Animal glue has existed since ancient times, although its use was not widespread. Glue deriving from horse teeth can be dated back nearly 6000 years, but no written records from these times can prove that they were fully or extensively used. The first known written procedures for making animal glue were produced around 2000 BC. Between 1500 and 1000 BC, it was used for wood furnishings and mural paintings, and is found on the caskets of Egyptian pharaohs. Evidence for its use comes in the form of stone carvings depicting glue preparation and use. Egyptian records state that animal glue would be made by melting it over a fire and then applied with a brush. Ancient Greeks and Romans later used animal and fish glue to develop veneering and marquetry, the bonding of thin sections or layers of wood. Animal glue, known as taurokolla (ταυρόκολλα) in Greek and gluten taurinum in Latin, was made from the skins of bulls in antiquity. Broken pottery might also be repaired with the use of animal glues, filling the cracks to hide imperfections. About 906–618 BC, fish, ox horns and stag horns were used to produce adhesives and binders for pigments in China. Animal glues were employed as binders in paint media during the Tang dynasty. They were similarly used on the Terracotta Army figures. Records indicate that one of the essential components of lampblack ink was proteinaceous glue. Ox glue and stag-horn glues bound particles of pigments together, acting as a preservative by forming a film over the surface as the ink dried.
Educational resource materials (including animations) by the American Society for Bone and Mineral Research Review (including references) of piezoelectricity and bone remodelling A good basic overview of bone biology from the Science Creative Quarterly Bone histology photomicrographs Archived 6 July 2020 at the Wayback Machine
== Reception == The level's originality and tonal shift caused it to stand out to critics. GamesRadar+ journalist Alex Avard praised "We Don't Go To Ravenholm..." as an example of a horror sequence in a non-horror game, describing it as "harrowing" and a "blood-soaked frightfest". Fellow GamesRadar+ journalist Ashley Reed praised the game's inclusion of "Zombie Chopper", an achievement which forced the player to beat the entire level employing only the Gravity Gun, arguing that not using weapons forced them to think creatively about how to proceed through the level, turning to items such as saw blades as improvised weaponry and employing strategies such as fleeing the zombies before they could notice the character's presence. The level was also praised for its effective use of horror elements. Den of Geek journalist Matthew Byrd described Ravenholm as "the perfect horror level", stating that it both served as a send up of horror tropes and effectively utilized them to scare the player. Suggesting that it "just happened to be the perfect idea released at the perfect time", Byrd further stated that some elements of the level "certainly don't feel quite as groundbreaking" 15 years later as they did upon the game's release. PC Gamer journalist Andy Kelly included the game on the list of his best first-person shooter levels ever, calling it "a tense, terrifying gauntlet" and "probably the best level Valve has ever designed". Screen Rant journalist Padraig Cotter argued that the level was "arguably the game's most famous" and had a "perfect balance" of horror and action.
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.
Semax is a synthetic seven-amino-acid peptide derived from a fragment of corticotropin. It is used in Russia as a nasal preparation, while elsewhere it is studied as a research compound. It is not approved as a medicine in most countries.