The short version of ACTH(4-10) fits in a sentence. The long version — which is the one that helps — is below.
This page was last updated on 2025-11-21 and is reviewed periodically as new material appears.
Verification of a supplied batch generally combines a certificate of analysis with independent testing, because certificates are self-reported documents. A typical package includes a chromatographic trace, a mass spectrum, and a stated water or counter-ion content. Batch-to-batch consistency matters more than a single purity figure when results are compared across experiments. No single mandatory standard governs research-grade peptide release, so laboratories are expected to define their own acceptance criteria. Residual trifluoroacetate from purification is a frequently overlooked counter-ion.
Lyophilized material is chemically stable for extended periods when kept dry, cold, and protected from light. The powder is hygroscopic, so vials should be warmed to room temperature before opening to reduce condensation on the contents. Once dissolved, the peptide is far less stable because peptide bonds are susceptible to hydrolysis and the methionine residue can oxidize. Solutions are typically aliquoted and held at 2-8 °C for short intervals or frozen for longer ones, and repeated freeze-thaw cycles should be avoided.
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.
| Property | Value | Notes |
|---|---|---|
| Typical purity | 95% or higher | By reversed-phase HPLC area |
| Identity method | Electrospray mass spectrometry | Confirms molecular mass |
| Purity method | Reversed-phase HPLC | Detection near 214 nm |
| Primary degradation | Methionine oxidation | Sulfoxide product, +16 Da |
| Solution storage | 2-8 °C, short term | Aliquot to avoid freeze-thaw |
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.
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.
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.
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.
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.
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.
Congress passed the Authorization for the use of Military Force Against Terrorists, which grants the President the authority to use all "necessary and appropriate force" against those whom he determined "planned, authorized, committed or aided" the September 11 attacks or who harbored said persons or groups. It is still in effect. On October 7, 2001, the war in Afghanistan began when U.S. and British forces initiated aerial bombing campaigns targeting Taliban and al-Qaeda camps, then later invaded Afghanistan with ground troops of the Special Forces. This eventually led to the overthrow of the Taliban's rule of Afghanistan with the Fall of Kandahar on December 7, by U.S.-led coalition forces.
The ions are transferred from ionization source and hold at a punch-valve and injected to MS periodically. The performance of a hand-held Mini-10 mass spectrometer was upgraded with negative ion mode for detecting explosive compounds and hazardous materials at the picogram level, which is highly applicable for airport luggage checking.
== Uses == Polymersomes that contain active enzymes and that provide a way to selectively transport substrates for conversion by those enzymes have been described as nanoreactors. Polymersomes have been used to create controlled release drug delivery systems. Similar to coating liposomes with polyethylene glycol, polymersomes can be made invisible to the immune system if the hydrophilic block consists of polyethylene glycol. Their permeability can be modulated by exogenous factors, for example by incorporation of stimuli-responsive molecules such as photoswitches, or pH responsive groups. Thus, polymersomes are useful carriers for targeted drug delivery. For in vivo applications, polymersomes are de facto limited to the use of FDA-approved polymers, as most pharmaceutical firms are unlikely to develop novel polymers due to cost issues. Fortunately, there are a number of such polymers available, with varying properties, including: Hydrophilic blocks
== Further reading == C. Siefridt, Cadmium contamination in the EU : A growing challenge, European Parliament Research Service, 2026. Hartwig, Andrea (2013). "Cadmium and Cancer". In Astrid Sigel; Helmut Sigel; Roland K. O. Sigel (eds.). Cadmium: From Toxicity to Essentiality. Metal Ions in Life Sciences. Vol. 11. Springer. pp. 491–507. doi:10.1007/978-94-007-5179-8_15. ISBN 978-94-007-5178-1. PMID 23430782. Agency for Toxic Substances and Disease Registry (ATSDR) (2012). Toxicological Profile for Cadmium. U.S. Department of Health and Human Services, Public Health Service. https://www.atsdr.cdc.gov/toxprofiles/tp5.pdf Nordberg, Gunnar F. (2007). Handbook on the toxicology of metals (3rd ed.). Academic Press. pp. 445–486. ISBN 978-0-12-369413-3.
== Function == The transitional epithelium cells stretch readily in order to accommodate fluctuation of volume of the liquid in an organ (the distal part of the urethra becomes non-keratinized stratified squamous epithelium in females; the part that lines the bottom of the tissue is called the basement membrane). Transitional epithelium also functions as a barrier between the lumen, or inside hollow space of the tract that it lines and the bloodstream. To help achieve this, the cells of transitional epithelium are connected by tight junctions, or virtually impenetrable junctions that seal together to the cellular membranes of neighboring cells. This barrier prevents re-absorption of toxic wastes and pathogens by the bloodstream.
Sources: en.wikipedia.org
== History == The study of lichen acids related to protolichesterinic acid began in 1845, when Schnedermann and Wilhelm Knop isolated lichesterinic acid from Cetraria islandica var. vulgaris. They determined it had a melting point around 120 °C (248 °F) and established its composition as C19H32O4. Further research by H. Sinnhold in 1898 worked with pure lichesterinic acid (melting point 124.5–125 °C). In 1900, Oswald Hesse isolated three varieties (α-, β-, and γ-) of lichesterinic acid from Cetraria islandica, with specific rotations of +27.9°, +27.9°, and +16° respectively. Protolichesterinic acid was first isolated at the beginning of the 20th century by Friedrich Wilhelm Zopf from the lichen Cetraria cucullata (now known as Cladocetraria cucullata). Zopf initially found it alongside usnic acid and noticed that while it showed similarities to lichesterinic acid in some properties, it differed significantly in melting point and other characteristics. The compound was named "protolichesterinic acid" to reflect its close relationship to lichesterinic acid, and the discovery was published in Liebigs Annalen in 1902. After obtaining it in crystalline form through extraction with ether and recrystallization from warm benzol, Zopf determined that protolichesterinic acid formed thin, rhombic, pearly plates that melted at 103–104 °C (217–219 °F), lower than lichesterinic acid's melting point of 124–125 °C (255–257 °F).
Urquía Carreño amended the vote to add a third proposal, to allow him some time to replace the money, and not say anything. Voting on the order of most to least destructive, the Board voted unanimously to reject on Urquía Carreño's proposal. They then voted unanimously to proceed with the first two proposals. Urquía Carreño said that he was committed to repaying the money. The Board told him not to leave the country, and to cancel his upcoming trips. The Board then spent a long time in deliberation about why Urquía Carreño had waited four days to inform Viñas Alonso about the missing money. The police report was filed at the Zanja y Dragones Police Station.
==== Application process ==== There is no centralized selection process for internship or residency positions. The application process is more similar to that of other jobs on the market—i.e. application via cover letter and curriculum vitae. Both types of positions are however usually publicly advertised and many hospitals have nearly synchronous recruitment processes once or twice per year—the frequency of recruitment depending mainly on hospital size—for their internship positions.
==== Tolerance ==== Tolerance is a process characterized by neuroadaptations that result in reduced drug effects. While receptor upregulation may often play an important role other mechanisms are also known. Tolerance is more pronounced for some effects than for others; tolerance occurs slowly to the effects on mood, itching, urinary retention, and respiratory depression, but occurs more quickly to the analgesia and other physical side effects. However, tolerance does not develop to constipation or miosis (the constriction of the pupil of the eye to less than or equal to two millimeters). This idea has been challenged, however, with some authors arguing that tolerance does develop to miosis. Tolerance to opioids is attenuated by a number of substances, including:
=== Litigation === This drug has been the subject of litigation; more than 13,000 people have sued Wyeth between 2002 and 2009. Wyeth and Pharmacia & Upjohn prevailed in the vast majority of hormone therapy cases previously set for trial through a combination of rulings by judges, verdicts by juries, and dismissals by plaintiffs themselves. Of the company's losses, two of the jury verdicts were reversed post-trial and others are being challenged on appeal. Wyeth also won five summary judgments on Prempro cases and had 15 cases voluntarily dismissed by plaintiffs. The company won dismissals in another 3,000 cases. In 2006, Mary Daniel, in a trial in Philadelphia, was awarded $1.5 million in compensatory damages as well as undisclosed punitive damages. As of 2010, Wyeth had won the last four of five cases, most recently in Virginia, finding that they were not responsible for the breast cancer of plaintiff Georgia Torkie-Tork. Wyeth has been quoted as saying "many risk factors associated with breast cancer have been identified, but science cannot establish what role any particular risk factor or combination play in any individual woman's breast cancer." Wyeth's counsel in the case also noted that in the WHI trial, 99.62% of women took the drug and "did not get breast cancer".
Sources: en.wikipedia.org
===== Scotland ===== There are four NHS Scotland Gender Identity Clinics providing services to adults and a separate service for younger people. The National Gender Identity Clinical Network for Scotland reported in 2021 that some patients had waited in excess of two years from referral for their first appointment. Minister for Public Health Maree Todd has stated that the Scottish Government wants to reduce "unacceptable waits to access gender identity services". Research has indicated patient dissatisfaction with long wait times. However, overall experience of treatment outcomes was largely positive, particularly for hormone therapy and surgery.
== Etymology and naming == The most common English names for the species include great white shark, white shark, and the Australian English variant white pointer. These names refer to its white underside, which is noticeable in dead sharks lying upside down. Colloquial use favors the name 'great white shark' or simply 'great white', with 'great' perhaps emphasizing the size and power of the species. Scientists typically use 'white shark' or 'the white shark' as no "lesser white shark" exists for comparison, though some use 'white shark' to refer to all members of the Lamnidae. The scientific generic name, Carcharodon, combines two Greek words. The prefix carchar- is derived from κάρχαρος (kárkharos), which means "sharp". The suffix -odon derives from ὀδών (odṓn), which translates to "tooth". The specific name carcharias is from the καρχαρίας (karkharías), the Ancient Greek word for shark. The white shark was one of the species originally described by Carl Linnaeus in his 1758 10th edition of Systema Naturae and assigned the scientific name Squalus carcharias, Squalus being the genus in which he placed all sharks. By the 1810s, the shark was recognized as needing to be placed in a new genus, but not until 1838 did Sir Andrew Smith coin the name Carcharodon as the new genus. A few attempts have been made to describe and classify the white shark before Linnaeus. One of the earliest mentions of it in literature as a distinct type of animal appears in a 1553 book by Pierre Belon.
=== Rhinopharyngitis mutilans === Rhinopharyngitis mutilans, also known as gangosa, is a destructive ulcerative condition that usually originates about the soft palate and spreads into the hard palate, nasopharynx, and nose, resulting in mutilating cicatrices, and outward to the face, eroding intervening bone, cartilage, and soft tissues. It occurs in the late stages of yaws, usually 5 to 10 years after the first symptoms of infection. This is now rare. Very rarely, yaws may cause bone spurs in the upper jaw near the nose (gondou); gondou was rare even when yaws was a common disease.
====== Stimulation of inflammasome helps protect against SeV infection ====== Using human embryonic kidney cells (HEK 293T) it has been shown that SeV can stimulate production of a pattern recognition receptor NLRC5, which is a cytosolic protein expressed mainly in hematopoietic cells. This production activates the cryopyrin (NALP3) inflammasome. Using human monocytic cell line-1 (THP-1) it has been shown that SeV can activate signal transduction by mitochondrial antiviral-signaling protein signaling (MAVS), which is a mitochondria-associated adaptor molecule that is required for optimal NALP3-inflammasome activity. Through MAVS signaling SeV stimulates the oligomerization of NALP3 and triggers NALP3-dependent activation of caspase-1 that, in turn, stimulates caspase 1-dependent production of interleukine -1 beta (IL-1β).
Sources: en.wikipedia.org
Dry powder is normally held at -20 °C or lower, away from light and moisture. Sealed vials can also be kept at 2-8 °C for shorter intervals. Warming to room temperature before opening prevents condensation.
In solution, hydrolysis of peptide bonds and oxidation of the methionine residue are the principal concerns. Oxidation converts methionine to its sulfoxide form, shifting the mass by sixteen daltons. Both processes are slowed by cold storage and by avoiding alkaline conditions.
A certificate documents what the supplier measured on a specific lot, not how a laboratory will use the material. Independent verification of identity and purity is common practice. Acceptance criteria should be defined before a batch is ordered.
Semax is based on the ACTH(4-10) fragment, a seven-amino-acid segment of adrenocorticotropic hormone. The synthetic peptide retains the core sequence while removing regions associated with endocrine activity. This modification is intended to isolate effects on the nervous system.