ACTH(4-10) 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 2025-09-30 and is reviewed periodically as new material appears.
Pharmacokinetic accounts emphasize rapid breakdown. After intravenous dosing the intact peptide disappears from blood within minutes, and nasal delivery produces low but measurable concentrations. Metabolites rather than the parent molecule may account for part of the observed activity, although the relative contribution is unresolved. Dosing in the literature varies widely and no optimal schedule has been agreed. These gaps are regularly cited as a reason the findings have not produced broad clinical adoption beyond the original research setting.
Proposed mechanisms center on neurotrophic signaling rather than on classical melanocortin receptor activation. Rodent experiments have reported shifts in the expression of brain-derived neurotrophic factor and nerve growth factor after administration, together with changes in the associated receptor systems. Several authors argue that the peptide acts largely through its degradation products and their interaction with peptidergic pathways, but this remains a hypothesis rather than a settled finding. No single molecular target has been identified in a way that the field broadly accepts.
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.
| Property | Value | Notes |
|---|---|---|
| Primary research models | Rodent studies | Largest share of published data |
| Reported markers | BDNF and NGF expression | Measured mainly in animal tissue |
| Common administration | Intranasal | Matches the registered formulation |
| Blood residence time | Minutes | Rapid enzymatic degradation |
| Evidence quality | Small trials, limited replication | Noted repeatedly in reviews |
Quality documentation for research-grade peptide usually includes a certificate of analysis stating purity, identity, and residual counterion content. Batch-to-batch variation in purity and salt form is a recognized issue, and comparisons across suppliers require attention to the exact counterion, for example acetate versus trifluoroacetate. Sequence verification by tandem mass spectrometry provides stronger evidence than a single mass measurement. For any study reporting biological results, the analytical method and the measured purity should be stated explicitly. Independent verification of supplier claims is considered good practice.
Semax is supplied as a lyophilized powder that appears white to off-white. It dissolves readily in water, phosphate-buffered saline, and other aqueous media, which simplifies preparation of working solutions for laboratory use. The nasal products registered in Russia are dilute aqueous solutions, typically around 0.1 percent peptide by weight. Organic solvents are rarely necessary and can complicate handling. Because the peptide is hygroscopic, weighing should be performed quickly and with minimal exposure to ambient humidity.
Solid material is normally kept at minus 20 degrees Celsius in a sealed, desiccated container. Reconstituted solutions are less stable and are usually divided into single-use aliquots before freezing. Repeated freeze-thaw cycles are avoided because they promote aggregation and loss of activity. Light exposure is minimized by using amber glassware or foil wrapping. Published stability data for this peptide are sparse, so recommended storage conditions rest mainly on general practice for short synthetic peptides rather than on dedicated study.
Regulatory status differs sharply between jurisdictions. In Russia the peptide is registered as a prescription nasal preparation, while agencies such as the United States Food and Drug Administration have not approved it for any indication. Products sold elsewhere are typically labeled for laboratory research only, and such labels shift responsibility for safe handling to the purchaser. Because the same name covers pharmaceutical-grade nasal drops and bulk research powder, identity and purity documentation becomes the main practical concern when comparing sources.
Semax is a synthetic seven-amino-acid peptide whose sequence extends the ACTH(4-10) fragment with a C-terminal proline-glycine-proline tripeptide. The commonly cited sequence is Met-Glu-His-Phe-Pro-Gly-Pro, giving a molecular formula near C37H51N9O10S and a molecular weight close to 813.9 g/mol. It belongs to the broader class of synthetic ACTH fragments studied for central nervous system effects rather than for adrenal steroid stimulation. In practice the material appears as a lyophilized white powder for laboratory work or as a dilute saline solution in clinical settings.
Development is attributed to researchers at the Institute of Molecular Genetics in Moscow during the early 1980s, building on earlier Soviet work with ACTH fragments. Russian regulatory approval followed for intranasal use, and the compound has remained commercially available there for decades. Most published human data originate from Russian and, later, some Eastern European clinical reports, which are not always accessible in English translation. Outside that region the material is generally handled as a research chemical rather than a licensed medicine.
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.
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.
The proposed mechanism centres on neurotrophic signalling rather than direct receptor activation. Semax is reported to increase expression of brain-derived neurotrophic factor and nerve growth factor in several brain regions, and to shift the balance between excitatory and inhibitory neurotransmitter systems. Interaction with melanocortin receptors has been suggested because of the parent ACTH fragment. Many of these findings come from rodent studies, and the extent to which they translate to human physiology remains an open question.
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.
Others, like the Japanese flying squid, will spawn neutrally buoyant egg masses which will float at the interface between water layers of slightly different densities, or the female will swim around while carrying the eggs with her. Most species are semelparous (only reproduce once before dying), the only known exceptions are the vampire squid, the lesser Pacific striped octopus and the nautilus, which are iteroparous. In some species of cephalopods, egg clutches are anchored to substrates by a mucilaginous adhesive substance. These eggs are swelled with perivitelline fluid (PVF), a hypertonic fluid that prevents premature hatching. Fertilized egg clusters are neutrally buoyant depending on the depth that they were laid, but can also be found in substrates such as sand, a matrix of corals, or seaweed. Because these species do not provide parental care for their offspring, egg capsules can be injected with ink by the female in order to camouflage the embryos from predators.
Thiafentanil (A-3080, Thianil) is a highly potent opioid analgesic that is an analog of fentanyl, and was invented in 1986. Its analgesic potency is slightly less than that of carfentanil (itself approximately 10,000 times the potency of morphine, or 4,000 times that of heroin), though with a faster onset of effects, shorter duration of action and a slightly lesser tendency to produce respiratory depression. It is used in veterinary medicine to anesthetise animals such as impala, usually in combination with other anesthetics such as ketamine, xylazine or medetomidine to reduce the prevalence of side effects such as muscle rigidity.
=== Underlying mechanisms === Desmoplasia is thought to have a number of underlying causes. In the reactive stroma hypothesis, tumor cells cause the proliferation of fibroblasts and subsequent secretion of collagen. The newly secreted collagen is similar to that of collagen in scar formation – acting as a scaffold for infiltration of cells to the site of injury. Furthermore, the cancer cells secrete matrix degrading enzymes to destroy normal tissue ECM thereby promoting growth and invasiveness of the tumor. Cancer associated with a reactive stroma is typically diagnostic of poor prognosis. The tumor-induced stromal change hypothesis claims that tumor cells can dedifferentiate into fibroblasts and, themselves, secrete more collagen. This was observed in desmoplastic melanoma, in which the tumor cells are phenotypically fibroblastic and positively express genes associated with ECM production. However, benign desmoplasias do not exhibit dedifferentiation of tumor cells.
On September 18, during the second game of doubleheader against their division rivals, the Los Angeles Dodgers, with the Rockies down to their last out, trailing by a run, Helton hit a clutch two-run walk-off home run off Dodgers closer Takashi Saito, producing what may have been the most emotional moment of the regular season, turning what seemed like an imminent loss into an improbable victory, and helping propel the team toward an October run. The miracle home run kept the Rockies alive in the bid to win the wild card or perhaps even NL West title. The Rockies eventually clinched the NL wild card, in a 9–8 extra innings victory over the Padres in a wild card tie-breaker game, allowing Helton to appear in the playoffs for the first time in his career. The Rockies kept their run going into October. Having never won a playoff series in their history, the Rockies went on a rampage through the National League, winning every game they played in the NL playoffs, as they marched into the World Series. The team's first playoff opponent was the Philadelphia Phillies, who the Rockies swept in three games in the NL Division Series. Helton hit a triple on the first postseason pitch he ever faced, during the opening game of the NLDS in Philadelphia. In the second round of the playoffs, the Rockies faced the Arizona Diamondbacks, who they swept in four games of the NL Championship Series, sending the Rockies on their first trip to the World Series in franchise history.
After its expulsion from Malaysia, Singapore became independent as the "Republic of Singapore" on 9 August 1965, with Lee Kuan Yew and Yusof bin Ishak as the first prime minister and president respectively. In 1967, the country co-founded the Association of Southeast Asian Nations (ASEAN). Race riots erupted again in 1969 as a spillover from the 13 May incident in Malaysia. On this occasion, the unrest was more firmly contained. Lee's emphasis on rapid economic growth, racial integration, promotion of business entrepreneurship and curbs on democratic freedoms by governing with extensive legal powers shaped Singapore's policies for the next half century. Economic growth continued throughout the 1980s, with the unemployment rate falling to 3% and real GDP growth averaging at about 8% up until 1999. During the 1980s, Singapore began to shift towards high-tech industries, such as the wafer fabrication sector, in order to remain competitive as neighbouring countries began manufacturing with cheaper labour. Singapore Airlines was formed in 1972 and Changi Airport was opened in 1981, replacing the international airport at Paya Lebar. Lee's government capitalised on Singapore's favourable geographical position to develop the Port of Singapore into one of the world's busiest ports, while the service and tourism industries also expanded significantly during this period. The PAP has remained in power since 1959.
Sources: en.wikipedia.org
The gut is an endoderm-derived structure. At approximately the sixteenth day of human development, the embryo begins to fold ventrally (with the embryo's ventral surface becoming concave) in two directions: the sides of the embryo fold in on each other and the head and tail fold toward one another. The result is that a piece of the yolk sac, an endoderm-lined structure in contact with the ventral aspect of the embryo, begins to be pinched off to become the primitive gut. The yolk sac remains connected to the gut tube via the vitelline duct. Usually, this structure regresses during development; in cases where it does not, it is known as Meckel's diverticulum. During fetal life, the primitive gut is gradually patterned into three segments: foregut, midgut, and hindgut. Although these terms are often used in reference to segments of the primitive gut, they are also used regularly to describe regions of the definitive gut as well. Each segment of the gut is further specified and gives rise to specific gut and gut-related structures in later development. Components derived from the gut proper, including the stomach and colon, develop as swellings or dilatations in the cells of the primitive gut. In contrast, gut-related derivatives — that is, those structures that derive from the primitive gut but are not part of the gut proper, in general, develop as out-pouchings of the primitive gut. The blood vessels supplying these structures remain constant throughout development.
=== Pharmacodynamics === The mechanism and action of lipoic acid when supplied externally to an organism is controversial. Lipoic acid in a cell seems primarily to induce the oxidative stress response rather than directly scavenge free radicals. This effect is specific for RLA. Despite the strongly reducing milieu, LA has been detected intracellularly in both oxidized and reduced forms. LA is able to scavenge reactive oxygen and reactive nitrogen species in a biochemical assay due to long incubation times, but there is little evidence this occurs within a cell or that radical scavenging contributes to the primary mechanisms of action of LA. The relatively good scavenging activity of LA toward hypochlorous acid (a bactericidal produced by neutrophils that may produce inflammation and tissue damage) is due to the strained conformation of the 5-membered dithiolane ring, which is lost upon reduction to DHLA. In cells, LA is reduced to dihydrolipoic acid, which is generally regarded as the more bioactive form of LA and the form responsible for most of the antioxidant effects and for lowering the redox activities of unbound iron and copper. This theory has been challenged due to the high level of reactivity of the two free sulfhydryls, low intracellular concentrations of DHLA as well as the rapid methylation of one or both sulfhydryls, rapid side-chain oxidation to shorter metabolites and rapid efflux from the cell.
==== Zwitterionic surfactants ==== Zwitterionic (ampholytic) surfactants have both cationic and anionic centers attached to the same molecule. The cationic part is based on primary, secondary, or tertiary amines or quaternary ammonium cations. The anionic part can be more variable and include sulfonates, as in the sultaines CHAPS (3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate) and cocamidopropyl hydroxysultaine. Betaines such as cocamidopropyl betaine have a carboxylate with the ammonium. The most common biological zwitterionic surfactants have a phosphate anion with an amine or ammonium, such as the phospholipids phosphatidylserine, phosphatidylethanolamine, phosphatidylcholine, and sphingomyelins. Lauryldimethylamine oxide and myristamine oxide are two commonly used zwitterionic surfactants of the tertiary amine oxides structural type.
=== Lawsuits === On 12 January 2016, Dow Pharmaceutical Sciences and Valeant Pharmaceuticals North America LLC filed a lawsuit against Taro USA and Taro Industries, an Israel-based corporation. The lawsuit was filed for infringement upon their Onexton patent, by Taro attempting to submit an abbreviated new drug application (ANDA) to the Food and Drug Administration (FDA) for its generic 3.75% benzoyl peroxide and 1.2% clindamycin phosphate topical gel. The court concluded that Taro was guilty of attempting to submit an ANDA patent request before the Onexton patent expired. Perrigo settled its patent litigation with Valeant and Dow.
The resultant PCR amplicons encoding fl-DHX8 (M1 to R1220) or DHX8Δ547 (A548 to R1220) are inserted into the "pFBDM" vector downstream of the polyhedrin promoter. Both, vector and insert, are digested with BamHI and NotI restriction enzymes.
Sources: en.wikipedia.org
== Ion exchange resins == Ion exchange resins are the physical medium that facilitates ion exchange reactions. The resin is composed of cross-linked organic polymers, typically polystyrene matrix and functional groups where the ion exchange process takes place.
For services to Youth Football. Jane Loveys. Director, Campus Services, University of Bath. For services to Higher Education. Geoffrey Lowe. Crew Manager, Norfolk Fire and Rescue Service. For services to the community in Norfolk. Joan Lynas. For services to the Girls' Brigade and to the community in Newtownabbey, Northern Ireland. Kevin Philip Macey. Head of Major Crime Review, Essex Police. For services to Policing. John Alexander Mackintosh. Fundraiser, Cancer Research UK. For voluntary services to Cancer Patients and to the community in Elgin. Veronica Maclean. Patron, Moray Fundraising Group, Marie Curie. For voluntary services to Cancer Patients in Moray. Mubarak Hussain Mahmed. Well-Being and Engagement Co-ordinator, First Bus North and West Yorkshire. For services to Mental Health. Christopher Marsay. Watch Manager, Cleveland Fire and Rescue Service. For services to the community in North Yorkshire. Jeremy Paul McCluskey. Front of House and Security Guard, G4S Security. For Public Service, particularly during Covid-19. Robert John McCormick. Security Team Leader, Hillsborough Castle and Gardens. For Public Service. Jodie McFarlane. Detective Constable, Police Service of Scotland. For services to Children and Families in Ayrshire. Patrick Eugene McGeehan. Coach, Santos Football Club. For voluntary service to Association Football in Northern Ireland. Myrtle Edna McIlveen. Volunteer Manager, Killyleagh Community Charity Shop. For voluntary services to the community in County Down. Matthew McKenzie. Insight Volunteer, Carers UK. For services to Carers.
White sharks communicate with each other through a complex array of body language. Most behaviors have been observed at aggregations around seal rookeries shortly after peak hunting periods, where sharks engage in extensive socializing. At least 20 unique forms of body language are known, most of which consist of two sharks swimming in passing, parallel, or circular patterns to ritualistically examine one another. Occasionally, one shark will openly show off its body in a lateral display to the other. It is hypothesized that the main purpose of these interactions is to establish social rank by size to avoid competition. Observations by Sperone and colleagues in 2010 found display behaviors to be more common between individuals of similar size where differences are not immediately obvious. There is no evidence that sex is a significant factor in behavioral patterns. With dominance established, the smaller shark then acts submissively towards the larger shark by yielding during subsequent encounters or simply avoiding confrontation. Body language is less frequent in California and Australia compared to Dyer Island in South Africa. It is thought that this is because the former locations are less densely populated, and so sharks there are more familiar with each other's hierarchy. Direct violence is extremely rare, as individuals typically end conflicts through peaceful means. Splash fights appear to be the most common way of resolving ownership disputes over prey. Here, one shark slaps the surface with its tail to splash water at the competing shark.
Corrugated boxes are commonly used as shipping containers (more than 90% of all shipping containers are of this type). They are made of corrugated fiberboard which is lightweight, recyclable, and strong enough to ship a variety of products.
The composition of Euryapsida was uncertain. Ichthyosaurs were, at times, considered to have arisen independently of the other euryapsids, and given the older name Parapsida. Parapsida was later discarded as a group for the most part (ichthyosaurs being classified as incertae sedis or with Euryapsida). However, four (or three if Euryapsida is merged into Diapsida) subclasses remained more or less universal for non-specialist work throughout the 20th century. It has largely been abandoned by recent researchers: In particular, the anapsid condition has been found to occur so variably among unrelated groups that it is not now considered a useful distinction.
Sources: en.wikipedia.org
The main proposal is modulation of neurotrophic factors such as brain-derived neurotrophic factor, supported largely by animal experiments. Receptor-level targets have not been firmly established. Most reviews describe the mechanism as only partially characterized.
The compound is registered as a medicine in Russia, so clinical work has concentrated there. Trials elsewhere are few and generally small. This geographic concentration is a recognized limitation in evidence reviews.
Some fraction may reach the central nervous system through olfactory pathways, and this is often cited as the rationale for the nasal route. The size of that fraction in humans is not well quantified. Blood concentrations after nasal dosing are low, which complicates measurement.
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.