ACTH 片段 raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
This page was last updated on 2026-08-01 and is reviewed periodically as new material appears.
Reported pharmacological work centers on neurotrophic signaling, including changes in BDNF and NGF expression in hippocampal tissue in animal models. Human data come largely from studies conducted in Russia, and how well those results generalize to other populations remains an open question. Regulatory status differs sharply by jurisdiction: Semax is a registered prescription medicine in Russia, while it holds no approved marketing status in the United States or the European Union. Outside such jurisdictions it is generally handled as a research chemical, which affects both documentation and quality expectations.
Semax is a synthetic heptapeptide whose sequence is Met-Glu-His-Phe-Pro-Gly-Pro. It was developed as a fragment analog of adrenocorticotropic hormone, modeled specifically on the ACTH(4-10) region. The first four residues reproduce that fragment, while a Pro-Gly-Pro tripeptide is appended at the C-terminus. Work on the compound originated in Russia, where it entered clinical use as an intranasal preparation. Its sequence places it among short regulatory peptides studied for effects on the central nervous system rather than on the adrenal axis.
The C-terminal Pro-Gly-Pro extension is not incidental. Proline-rich tails are known to resist several common peptidases, and the published literature attributes the longer half-life of Semax, relative to unmodified ACTH fragments, to this feature. The modification also removes the melanocyte-stimulating and corticosteroidogenic activity that characterizes longer ACTH-derived sequences. Because the molecule is small and hydrophilic, it is typically formulated as an aqueous solution for intranasal or parenteral delivery. Acetylation or amidation at the termini appears in closely related research peptides and shifts the mass by a fixed increment.
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.
Pharmacological accounts link semax to melanocortin signalling and to modulation of neurotrophic factor expression, particularly brain-derived neurotrophic factor and nerve growth factor. Much of this evidence comes from rodent studies using intranasal delivery, a route chosen because it allows peptides to reach the central nervous system with limited systemic exposure. Whether the same mechanisms operate in humans at comparable magnitude remains an open question. The precise receptor or receptors responsible for the reported behavioural and neuroprotective effects have not been conclusively identified.
| Property | Value | Notes |
|---|---|---|
| Molecular weight | ~813.9 Da (free heptapeptide) | N-acetylated form is about 42 Da heavier |
| Residue count | 7 (heptapeptide) | Four residues from ACTH(4-10), three added |
| Appearance | White to off-white powder | Usually supplied lyophilized |
| Solubility class | Freely soluble in water | Also dissolves in DMSO and polar organic solvents |
| Related parent fragment | ACTH(4-10) | Parent motif is Met-Glu-His-Phe |
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Its chain combines the first seven residues of corticotropin with a C-terminal proline-glycine-proline extension, a modification intended to slow enzymatic breakdown. The free peptide has a molecular mass near 813.9 daltons. It belongs to the class of ACTH-derived fragments studied for central nervous system activity rather than for adrenal steroid stimulation. This structural relationship to a natural hormone fragment is the usual starting point for describing the compound in the literature.
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.
Scientific literature on semax is unevenly distributed. A substantial share of published work originates from a small number of laboratories in Russia, while independent replication elsewhere is limited. Human data consist mostly of small trials with short follow-up, and several reported outcomes rely on subjective rating scales. Questions about how much intact peptide reaches the central nervous system after nasal administration, and how long it persists there, are still unresolved. The compound is best described as an active research subject rather than a settled pharmacological agent.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It was derived from the ACTH(4-10) fragment, a short segment of adrenocorticotropic hormone that lacks the hormonal activity associated with the full-length peptide. Researchers at the Institute of Molecular Genetics in Moscow developed the compound during the 1980s. It has been registered as a pharmaceutical product in Russia and several neighbouring countries, where it is supplied as a nasal solution, and it is also sold internationally as a research chemical.
当时的短肽研究普遍关注能否穿越血脑屏障、在低剂量下产生中枢效应，Semax 属于这一路线。鼻内给药是其主要使用方式，俄语文献报道的适应症涵盖缺血性卒中、短暂性脑缺血发作、认知功能减退以及视神经病变。这些研究大多发表在当地期刊上，样本规模与终点设置同西方试验惯例存在差异，国际同行对其临床证据的强度看法不一。
各国监管态度分化明显。俄罗斯按处方药管理，部分东欧国家留有使用记录；欧盟与美国未批准其作为药物上市，市面流通品通常标注为研究用化学品。身份差异意味着标示含量、纯度与无菌性缺少统一核查。体育领域还牵涉反兴奋剂名录，跨境携带则受目的地药品法规约束。
Semax is a synthetic heptapeptide whose sequence is Met-Glu-His-Phe-Pro-Gly-Pro. The first four residues correspond to the ACTH(4-10) fragment, while the terminal Pro-Gly-Pro extension was added to improve metabolic stability. Its molecular formula is C37H51N9O10S and its monoisotopic mass is approximately 813.9 Da. The compound is classified as a peptide research chemical and as a registered pharmaceutical product in Russia, but it does not hold marketing approval in the European Union or the United States. Naming conventions vary across supplier catalogs.
Development of the compound took place in the Soviet Union during the 1980s, largely through peptide research groups affiliated with the Shemyakin-Ovchinnikov Institute and Moscow State University. Investigators screened fragments of adrenocorticotropic hormone for activity on the central nervous system while attempting to separate cognitive effects from hormonal ones. The shortened sequence was selected because it retained behavioral activity in animal models without stimulating corticosteroid release. Early publications described the molecule as an ACTH(4-10) analog.
These four identified subtypes correlate with the consistency of the stool, which can be determined by the Bristol stool scale. In 2007, the Mayo Clinic College of Medicine in Rochester, Minnesota, United States, reported a piece of epidemiological research conducted on a population of 4,196 people living in Olmsted County Minnesota, in which participants were asked to complete a questionnaire based on the Bristol stool scale.
In 2005, Katja Seipel and Volker Schmid suggested that cnidarians and ctenophores are simplified descendants of triploblastic animals, since ctenophores and the medusa stage of some cnidarians have striated muscle, which in bilaterians arises from the mesoderm. They did not commit themselves on whether bilaterians evolved from early cnidarians or from the hypothesized triploblastic ancestors of cnidarians. Resolving the evolutionary relationships within Cnidaria has also been challenging, with almost every possible combination of clades being proposed. As time went on though, a semi-consensus has started to emerge. The enigmatic Polypodium hydriforme and subphylum Myxozoa have been firmly placed within the Cnidaria and have been shown to be closely related to the Medusozoa. In addition, these two groups have been found to likely be each other's closest relatives which, if true, would form the clade "Endocnidozoa". The relationships within the Medusozoa are currently probably the most contentious part of the tree. Traditionally, the class Scyphozoa also included Staurozoa and Cubozoa, but significant morphological differences eventually lead to the split of the three. The group containing them has since been named "Acraspeda". The relationships between these three and Hydrozoa have since and still are debated. A relationship between Scyphozoa and Cubozoa with Staurozoa as its sister has seen support in nearly all studies, but the position of the remaining class, Hydrozoa, is not understood.
Another Half-Life 2 episode was developed by Junction Point Studios, led by Warren Spector. The episode showed how the town of Ravenholm from Half-Life 2 became infested with headcrabs and zombies, with the return of the character of Father Grigori. It included a "magnet gun", which fired projectiles that magnetized metal surfaces and attracted objects and enemies, and was used for combat and puzzles. Junction Point worked on the game for a year, producing enough content to demonstrate one section, and a vertical slice that demonstrated the magnet gun. Valve lost interest in the project and Junction Point, who had been acquired by Disney Interactive Studios partway through, canceled it to instead develop Epic Mickey. Screenshots appeared in early 2017.
==== Marine algae ==== The factors affecting δD of algal lipids are: δD of water, algal species (up to 160%), lipid type (up to 170%), salinity (+0.9±0.2% per PSU), growth rate (0 ~ −30% per day) and temperature (−2 ~ −8% per °C). In a study by Zhang et al. (2009), the δDs of fatty acids in Thalassiosira pseudonana chemostat cultures were −197.3‰, −211.2‰ and −208.0‰ for C14, C16 and C18 fatty acids respectively. The δD of C16 fatty acid in the algae A. e. unicocca at 25°C, was determined using the empirical equation y = 0.890x − 91.730, where x is the δD of water at harvest. For another algal species, B. v. aureus, the equation was y = 0.869x − 74.651. The degree of D/H fractionation in most algal lipids increases with increasing temperature and decreases with increasing salinity. The growth rates have different impacts on the D/H fractionation depending on the species types.
== Coupled reactions == Since energy is released when ATP is broken down, energy is required to rebuild or resynthesize it. The building blocks of ATP synthesis are the by-products of its breakdown; adenosine diphosphate (ADP) and inorganic phosphate (Pi). The energy for ATP resynthesis comes from three different series of chemical reactions that take place within the body. Two of the three depend upon the food eaten, whereas the other depends upon a chemical compound called phosphocreatine. The energy released from any of these three series of reactions is utilized in reactions that resynthesize ATP. The separate reactions are functionally linked in such a way that the energy released by one is used by the other. Three processes can synthesize ATP:
Sources: en.wikipedia.org
For example, capillary electrophoresis or liquid chromatography could be used if the analyte can be ionized and has a high vapor pressure, but it is also soluble in polar solvents. On the other hand, gas chromatography is the best way to test a substance that is stable at high temperatures but has a low vapor pressure. When compared to gas or liquid chromatography, supercritical fluid chromatography is a better way to measure chiral inversion because it uses mass spectrometers and a green method.
=== Port Adelaide (2015–2019) === At the end of the 2014 season, Ryder left Essendon following the supplements saga. Ryder and his wife Jess were concerned for the health of their unborn child after he was allegedly told of the potential risks of the supplements program when interviewed by ASADA. Of the concern, Ryder stated that "At first we were really scared (about Harlan). What has panned out over a long period of time is that we felt badly let down by the club and lost trust and faith.” He nominated Port Adelaide as his preferred club of destination. Essendon were unwilling to trade Ryder initially, with Ryder and his management suggesting they would take Essendon to the AFL Grievance Tribunal because of the club's breach of its duty of care to players during the scandal. Ryder's manager also suggested that Ryder would consider retirement over returning to Essendon if a trade was blocked by the club. On 16 October, he was traded to the Power. Being Port Adelaide's big name recruit for season 2015, Ryder was unable to take part in the pre-season trial matches and was only cleared from his provisional suspension a few days prior to the round one game against Fremantle due to the ASADA drugs investigation. He played in 18 games for the Power, which included games where he kicked three goals in both showdowns and a four goals against his former club Essendon.
Jung was introduced to Freud's work by Bleuler whilst working at Burghölzli Hospital. Bleuler asked him to write a review of The Interpretation of Dreams (1899), which he read in 1900. In the early 1900s, psychology as a science was still in its early stages, but Jung became a qualified practitioner of Freud's new "psycho-analysis". Freud needed collaborators and pupils to validate and spread his ideas. Burghölzli was a renowned psychiatric clinic in Zurich, and Jung's research had already gained him international recognition. Jung sent Freud a copy of his Studies in Word Association in 1906. The same year, he published Diagnostic Association Studies, a copy of which he later sent to Freud, who had already purchased a copy. Preceded by a lively correspondence, Jung met Freud for the first time in Vienna on 3 March 1907.Jung recalled the discussion between himself and Freud as interminable and unceasing for 13 hours. Six months later, the then 50-year-old Freud sent a collection of his latest published essays to Jung in Zurich. This began an intense correspondence and collaboration that lasted six years. In 1908, Jung became an editor of the newly founded Yearbook for Psychoanalytical and Psychopathological Research. In the late summer of 1909, Jung sailed with Freud and Hungarian psychoanalyst Sándor Ferenczi to the United States. From 7–11 September, they took part in the twentieth-anniversary celebration of the founding of Clark University in Worcester, Massachusetts, the Vicennial Conference on Psychology and Pedagogy.
The Port of Dover is a cross-channel ferry, cruise terminal, maritime cargo and marina facility situated in Dover, Kent, south-east England. It is the nearest English port to France, at just 34 kilometres (21 mi) away, and is one of the world's busiest maritime passenger ports, with 11.7 million passengers, 2.6 million lorries, 2.2 million cars and motorcycles and 80,000 coaches passing through it in 2017, and with an annual turnover of £58.5 million a year. This compares with the nearby Channel Tunnel, the only fixed link between the island of Great Britain and the European mainland, which now handles an estimated 20 million passengers and 1.6 million trucks per year. The modern port facility features a large artificial harbour constructed behind stone piers and a defensive concrete breakwater. The port is divided into two main sections: the Eastern Docks serve as the main cross-channel ferry terminal, while the Western Docks contain a cruise ship terminal and a yacht marina along with cargo facilities. The Port of Dover has a long history and possesses several listed buildings and structures. The port is owned and operated by the Dover Harbour Board, a statutory corporation formed by royal charter in 1606 by King James I. Most of the board members of the Dover Harbour Board are appointees of the Department for Transport. The port has its own private police force, the Port of Dover Police. The current port traffic volumes and urban population categorise Dover as a Large-Port Town.
Sources: en.wikipedia.org
These models state that each IR monomer possesses 2 insulin binding sites; site 1, which binds to the 'classical' binding surface of insulin: consisting of L1 plus αCT domains and site 2, consisting of loops at the junction of FnIII-1 and FnIII-2 predicted to bind to the 'novel' hexamer face binding site of insulin. As each monomer contributing to the IR ectodomain exhibits 3D 'mirrored' complementarity, N-terminal site 1 of one monomer ultimately faces C-terminal site 2 of the second monomer, where this is also true for each monomers mirrored complement (the opposite side of the ectodomain structure). Current literature distinguishes the complement binding sites by designating the second monomer's site 1 and site 2 nomenclature as either site 3 and site 4 or as site 1' and site 2' respectively. As such, these models state that each IR may bind to an insulin molecule (which has two binding surfaces) via 4 locations, being site 1, 2, (3/1') or (4/2'). As each site 1 proximally faces site 2, upon insulin binding to a specific site, 'crosslinking' via ligand between monomers is predicted to occur (i.e. as [monomer 1 Site 1 - Insulin - monomer 2 Site (4/2')] or as [monomer 1 Site 2 - Insulin - monomer 2 site (3/1')]). In accordance with current mathematical modelling of IR-insulin kinetics, there are two important consequences to the events of insulin crosslinking; 1. that by the aforementioned observation of negative cooperation between IR and its ligand that subsequent binding of ligand to the IR is reduced and 2.
The first fossils assignable to this diverse group appear in the Early Triassic, after which teleosts accumulated novel body shapes predominantly gradually for the first 150 million years of their evolution (Early Triassic through early Cretaceous). The most basal of the living teleosts are the Elopomorpha (eels and allies) and the Osteoglossomorpha (elephantfishes and allies). There are 800 species of elopomorphs. They have thin leaf-shaped larvae known as leptocephali, specialised for a marine environment. Among the elopomorphs, eels have elongated bodies with lost pelvic girdles and ribs and fused elements in the upper jaw. The 200 species of osteoglossomorphs are defined by a bony element in the tongue. This element has a basibranchial behind it, and both structures have large teeth which are paired with the teeth on the parasphenoid in the roof of the mouth. The clade Otocephala includes the Clupeiformes (herrings) and Ostariophysi (carps, catfishes and allies). Clupeiformes consists of 350 living species of herring and herring-like fishes. This group is characterised by an unusual abdominal scute and a different arrangement of the hypurals. In most species, the swim bladder extends to the braincase and plays a role in hearing. Ostariophysi, which includes most freshwater fishes, includes species that have developed some unique adaptations. One is the Weberian apparatus, an arrangement of bones (Weberian ossicles) connecting the swim bladder to the inner ear.
=== Eating Disorder === To address the underlying eating disorder psychosocial interventions such as cognitive behavioral therapy, motivational therapy, problem-solving therapy, coping skills training, and family behavior therapy have all been shown to improve treatment adherence and achieve good glycemic control. It has been observed that addressing psychological needs improves HbA1c by 0.5%–1% in adults with T2DM. Useful therapies may involve cognitive behavioral therapy. Cognitive behavioral therapy focuses on changing unhealthy thinking surrounding the use of insulin. Family involvement and family therapy is helpful for long-term maintenance of good behaviors with taking insulin. A positive mindset to recovery, and connection with others who have experienced diabulimia, increases the probability of successful recovery.
Ghrelin receptors are located on neurons in this circuit. Hypothalamic ghrelin signalling is required for reward from alcohol and palatable/rewarding foods. Ghrelin has been linked to inducing appetite and feeding behaviors. Circulating ghrelin levels are the highest right before a meal and the lowest right after. Injections of ghrelin in both humans and rats have been shown to increase food intake in a dose-dependent manner. So the more ghrelin that is injected the more food that is consumed. However, ghrelin does not increase meal size, only meal number. Ghrelin injections also increase an animal's motivation to seek out food, behaviors including increased sniffing, foraging for food, and hoarding food. Body weight is regulated through energy balance, the amount of energy taken in versus the amount of energy expended over an extended period of time. Studies have shown that ghrelin levels are positively correlated with weight. This data suggests that ghrelin functions as an adiposity signal, a messenger between the body's energy stores and the brain. Ghrelin is not produced by some groups of animals. Among reptiles, snakes, chameleons and toadhead agamas have either lost the genes to produce ghrelin or the gene has become so mutated that it can no longer give rise to the protein hormone. A second gene, for MBOAT4 involved in ghrelin signalling is also absent. These animals can go for long periods without eating and commonly have their meals spaced weeks, months or even years apart.
=== Golimumab === Golimumab is a fully human IgG1 monoclonal antibody that was first approved by the FDA in 2009 to treat rheumatoid arthritis. Since, it has been approved to also treat psoriatic arthritis, ankylosing spondylitis, and moderately to severely active ulcerative colitis.
Sources: en.wikipedia.org
The sequence is Met-Glu-His-Phe-Pro-Gly-Pro, a seven-residue peptide. The first four residues correspond to the ACTH(4-10) fragment, and Pro-Gly-Pro is added at the C-terminus. N-acetylated versions also appear in the literature and differ in mass.
Semax is a synthetic analog of the ACTH(4-10) fragment rather than a copy of the full hormone. Truncation plus the added tail removes the steroidogenic portion of ACTH. That distinction explains why it is studied for nervous-system effects instead of adrenal stimulation.
It is registered as a prescription product in Russia and has been used there clinically, chiefly by the intranasal route. No approval exists in the United States or the European Union. Availability elsewhere typically falls under research-chemical distribution, with varying purity documentation.
It is described as a synthetic analogue of the ACTH(4–10) fragment, a short segment of adrenocorticotropic hormone. Its sequence differs from that fragment and includes two proline residues, which influence stability and behaviour in solution.