This is a working overview of methionine sulfoxide, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2025-12-13. Anything still debated is marked as such rather than presented as settled.
Regulatory status varies sharply by country. Semax is registered for medical use in Russia, where it appears in formularies as a nasal solution, and it also holds registration in a small number of neighbouring states. It has no approval from the United States Food and Drug Administration or the European Medicines Agency, and it is not a scheduled controlled substance in most jurisdictions. Elsewhere it circulates mainly as laboratory material, so purity documentation comes from suppliers rather than from a national pharmacopoeia.
Semax is a synthetic peptide created in the Soviet Union during the early 1980s by researchers working in Moscow. It was built from the short adrenocorticotropic hormone fragment known as ACTH(4-10), and the chain was then extended with three additional amino acids. The resulting molecule was named semax and entered clinical use in Russia in 1994. It is generally described as a nootropic and neuroprotective agent rather than as a hormone analogue.
Purity assessment relies mainly on reversed-phase high-performance liquid chromatography, which separates the target heptapeptide from truncated sequences, deletion analogues, and oxidised forms. Mass spectrometry, usually coupled to liquid chromatography, confirms identity through the expected molecular ion and reveals modifications such as methionine sulfoxide formation. Amino acid analysis can verify composition, and tandem mass spectrometry supports sequence confirmation. Ultraviolet detection near 254 to 280 nanometres is convenient because the phenylalanine and histidine residues absorb in that region. Nuclear magnetic resonance is rarely used for routine release testing.
Common degradation pathways include oxidation of the methionine side chain, hydrolysis of the peptide backbone, and aggregation under unfavourable pH or concentration. Stability studies typically monitor the main peak by chromatography and report total related substances as a percentage. Because no official monograph exists, acceptance criteria vary between laboratories, and reported purity values are not directly comparable across suppliers. Analysts therefore document the method, column, and detection wavelength alongside each result, and open questions remain about how much biological activity the oxidised forms retain.
Solid semax is typically supplied as a lyophilised powder that is hygroscopic and sensitive to moisture, light, and repeated temperature cycling. Long-term storage of the dry peptide is generally recommended at approximately -20 degrees Celsius, while shorter working periods may use refrigeration at 2 to 8 degrees Celsius. Vials should remain tightly closed and desiccated when brought to room temperature, because condensation can damage the material before it is weighed. Dividing a batch into aliquots is preferable to thawing one container repeatedly.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide | Analogue of the ACTH(4-10) fragment |
| Amino acid sequence | Met-Glu-His-Phe-Pro-Gly-Pro | Single-letter form MEHFPGP |
| Molecular formula | C37H51N9O10S | Free peptide, nominal mass near 814 Da |
| First registration | 1994, Russia | Nasal formulation for neurological indications |
| Typical purity grade | 95% or higher by HPLC | Research material; higher grades used as reference standards |
Clinical reports describe use in ischaemic stroke, transient ischaemic attack, optic nerve conditions, and cognitive complaints, but most of these studies are small and were conducted in a single region. Systematic reviews have generally described the evidence base as limited in size and variable in methodological quality. Randomised controlled data suitable for international regulatory assessment are scarce. As a result, major treatment guidelines outside Russia do not include the peptide, and interest in it remains largely research-driven rather than routine clinical.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It is described in the literature as an analogue of the ACTH(4–10) fragment, a short N-terminal portion of adrenocorticotropic hormone that retains some neurotropic activity without the full hormonal effects of the parent peptide. The molecule carries a methionine residue at the N-terminus and two proline residues near the C-terminus, features that shape both its interactions with receptor systems and its chemical stability. The free peptide corresponds to the formula C37H51N9O10S and a molecular mass near 813.9 Da.
The compound was developed in the 1980s at the Institute of Molecular Genetics in Moscow, where it emerged from research on short ACTH fragments and their effects on the central nervous system. Russian pharmaceutical listings describe it as a nootropic and neuroprotective agent, most often formulated as nasal drops. It is not a marketed medicine in the United States or the European Union, and no pharmacopoeial monograph covers it. Consequently, most published clinical experience with the substance originates from a small number of research centres, mainly in Russia and neighbouring countries.
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 compound was developed during the 1980s at the Institute of Molecular Genetics in Moscow as part of research on fragments of adrenocorticotropic hormone. Early work examined short ACTH-derived sequences that retained neurotrophic effects while lacking the endocrine activity of the full hormone. Semax entered clinical use in Russia during the 1990s, where it received registration for several neurological indications. Outside that region it remained primarily a laboratory research material rather than an approved therapeutic. English-language literature on it grew more slowly and frequently cited the original Russian studies.
Terminology around the compound varies by source. It appears in catalogues and papers as Semax, as the heptapeptide ACTH(4-7)-Pro-Gly-Pro, and under various alphanumeric laboratory codes used by individual suppliers. These names refer to the same sequence but may imply different salt forms, purity grades, or counter-ions. Peptide databases usually list the free base mass, while product descriptions sometimes report acetate or trifluoroacetate salts with a different formula weight. Because naming conventions for research peptides are not standardised across vendors, checking the declared sequence and measured mass is more reliable than relying on a trade name alone.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Its design combines the ACTH(4-7) core fragment with a C-terminal Pro-Gly-Pro extension, a modification intended to improve stability and prolong activity. The molecule is hydrophilic, carries no lipid chains or glycosylation, and has a theoretical mass just over 810 daltons in its free form. All seven residues are proteinogenic amino acids, so no non-natural building blocks appear in the backbone. A free N-terminal methionine and C-terminal proline define the unmodified parent peptide.
Prostaglandins have two derivatives: prostacyclins and thromboxanes. Prostacyclins are powerful locally acting vasodilators and inhibit the aggregation of blood platelets. Through their role in vasodilation, prostacyclins are also involved in inflammation. They are synthesized in the walls of blood vessels and serve the physiological function of preventing needless clot formation, as well as regulating the contraction of smooth muscle tissue. Conversely, thromboxanes (produced by platelet cells) are vasoconstrictors and facilitate platelet aggregation. Their name comes from their role in clot formation (thrombosis).
Lockheed implemented it into the L-1011 TriStar in 1973 at the request of Pacific Southwest Airlines (who used the baggage compartment as an entertainment lounge) and possibly also to suit potential Soviet buyers (see below). In October 1967, the Soviet government approved a Ministry of Civil Aviation (Aeroflot) specification for an aerobus. This called for 350 seats and a range of 3,600 kilometres (1,900 nautical miles) with a 40-tonne payload or 5,800 km (3,100 nmi) with seats taken but no freight. The airliner had to operate from smaller airports (classified as Klass "B" and "V" [Russian: класс "Б", "В"] or "Class B/C" by the Soviets) 2,600-metre (8,500 ft) runways. In the second half of the 1960s, OKB-240 (as the Ilyushin bureau was formally known) was restoring positions lost (with Yakovlev, in favour of Tupolev and Antonov) during the Khrushchev era and was well placed to secure design of the aerobus. When the Soviet cabinet's defence industry committee promoted the Aeroflot specification on September 8, 1969, to a preliminary project, (Russian: аванпроект; transliterated: avanproyekt), it entrusted it to Ilyushin. The bureau received specific operational requirements for the aerobus on February 22, 1970. In developing the concept which had been agreed, Ilyushin faced four challenges: configuration (layout or "shape"), powerplant, automation (avionics) and manufacturing capacity.
== Uses == HaloTagged fusion proteins can be expressed using standard recombinant protein expression techniques. Furthermore, there are several commercial vectors available that just require insertion of a gene of interest. Since bacterial dehalogenases are relatively small and the reactions described above are foreign to mammalian cells, there is no interference by endogenous mammalian metabolic reactions. Once the fusion protein has been expressed, there is a wide range of potential areas of experimentation including enzymatic assays, cellular imaging, protein arrays, determination of sub-cellular localization, and many additional possibilities. Recently, HaloTag has been engineered to create hybrid protein + small molecule biosensors of neuronal activity. These sensors undergo a conformational change in response to calcium concentration spikes during neuronal firing; this conformational change modulates the conformation of a HaloTag-bound dye molecule.
According to the 2021 Romanian census, Romania's population was 19,053,815. Like other countries in the region, its population is expected to decline gradually as a result of sub-replacement fertility rates and negative net migration rate. According to the 2021 Romanian census, Romanians made up 89.33% of the population, Hungarians 6.05% and the Roma 3.44% of the population, but many ethnicities are not recorded, as they do not have ID cards. International sources give higher figures for Roma than the official census. According to the Council of Europe, the Roma make up 8.32% of the population; this figure is difficult to verify due to the mobility of Roma and the reluctance of some of them to disclose their ethnicity. Hungarians constitute a majority in the counties of Harghita and Covasna. Other minorities include Ukrainians, Germans, Turks, Lipovans, Aromanians, Tatars, and Serbs. In 1930, there were 745,421 Germans living in Romania, but only about 36,000 remained in the country to this day. As of 2009, there were also approximately 133,000 immigrants living in Romania, primarily from Moldova and China. The total fertility rate (TFR) in 2018 was estimated at 1.36 children born per woman, which is below the replacement rate of 2.1, and one of the lowest in the world; it remains considerably below the high of 5.82 children born per woman in 1912. In 2014, 31.2% of births were to unmarried women.
3-Methylcrotonyl-CoA (β-Methylcrotonyl-CoA or MC-CoA) is an intermediate in the metabolism of leucine. It is found in mitochondria, where it is formed from isovaleryl-coenzyme A by isovaleryl coenzyme A dehydrogenase. It then reacts with CO2 to yield 3-methylglutaconyl-CoA, catalysed by 3-Methylcrotonyl-CoA carboxylase.
Sources: en.wikipedia.org
Colombia has more than 3,950 research groups in science and technology. iNNpulsa, a government body that promotes entrepreneurship and innovation in the country, provides grants to startups, in addition to other services it and institutions provide. Colombia was ranked 71st in the Global Innovation Index in 2025. Co-working spaces have arisen to serve as communities for startups large and small. Organizations such as the Corporation for Biological Research (CIB) for the support of young people interested in scientific work has been successfully developed in Colombia. The International Center for Tropical Agriculture based in Colombia investigates the increasing challenge of global warming and food security. Important inventions related to medicine have been made in Colombia, such as the first external artificial pacemaker with internal electrodes, invented by the electrical engineer Jorge Reynolds Pombo, an invention of great importance for those who suffer from heart failure. Also invented in Colombia were the microkeratome and keratomileusis technique, which form the fundamental basis of what now is known as LASIK (one of the most important techniques for the correction of refractive errors of vision) and the Hakim valve for the treatment of hydrocephalus. Colombia has begun to innovate in military technology for its army and other armies of the world; especially in the design and creation of personal ballistic protection products, military hardware, military robots, bombs, simulators and radar. Some leading Colombian scientists are Joseph M.
=== Non-peptides === CA7 – among smallest-known oxytocin receptor agonists; considerable selectivity over the vasopressin V1A receptor KNX-200 (KNX200) – series; chemical structure(s) not yet disclosed LIT-001 — improved social deficits in mice; non-selective over vasopressin receptors LIT-002 – highly potent, under formal development TC OT 39 – non-selective over vasopressin receptors WAY-267,464 – anxiolytic in mice; possibly non-selective over vasopressin receptors WJ0679 – among smallest-known oxytocin receptor agonists; produces prosocial effects in rodents In April 2025, a series of novel and highly potent small-molecule oxytocin receptor agonists with high selectivity over the vasopressin V1A receptor (up to >5,000-fold) were patented and described.
Province of German Bohemia (Provinz Deutschböhmen), the regions of northern and western Bohemia; proclaimed a constitutive state (Land) of the German-Austrian Republic with Reichenberg (Liberec) as capital, administered by a Landeshauptmann (state captain), consecutively: Rafael Pacher (1857–1936), 29 October – 6 November 1918, and Rudolf Ritter von Lodgman von Auen (1877–1962), 6 November – 16 December 1918 (the last principal city was conquered by the Czech army but he continued in exile, first at Zittau in Saxony and then in Vienna, until 24 September 1919). Province of the Sudetenland (Provinz Sudetenland), the regions of northern Moravia and Austrian Silesia; proclaimed a constituent state of the German-Austrian Republic with Troppau (Opava) as capital, governed by a Landeshauptmann: Robert Freissler (1877–1950), 30 October – 18 December 1918. This province's boundaries do not correspond to what would later be called the Sudetenland, which contained all the German-speaking parts of the Czech lands. Bohemian Forest Region (Böhmerwaldgau), the region of Bohemian Forest/South Bohemia; proclaimed a district (Kreis) of the existing Austrian Land of Upper Austria; administered by Kreishauptmann (district captain): Friedrich Wichtl (1872–1922) from 30 October 1918. German South Moravia (Deutschsüdmähren), proclaimed a District (Kreis) of the existing Austrian land Lower Austria, administered by a Kreishauptmann: Oskar Teufel (1880–1946) from 30 October 1918. The U.S.
Women are allowed to enter the Paris stock exchange and speculate. 1970: The concept of "head of the household" is abolished. Equality between spouses in managing the household is established. Parental authority is created. 1971: Introduction of maternity leave compensated at 90%. 1972: A law introduces the principle of equal pay between men and women; the first in a series of laws on the subject that are rarely enforced. Women are admitted to École Polytechnique. 1975: Law banning all discrimination in the civil service. Simone Veil passed a law decriminalizing and regulating voluntary termination of pregnancy (abortion). A husband can no longer read his wife's correspondence or control her relationships. All higher education is accessible to women. 1977: Abolition of the single wage allowance. 1982: Wives of tradesmen and artisans can choose between three statuses: collaborating spouse, employee, or partner. 1983: Law on pay equality between men and women, very poorly enforced. 1984: Parental leave is made available to either parent. 1986: Ministerial circular promoting the feminization of job titles: artisane, écrivaine, etc. 1987: Loosening of restrictions on night work. 1992: Law against sexual harassment. 2001: Strengthening of the 1983 law on professional equality. 2005: New law on professional equality, with no binding criteria or penalties in case of non-compliance. 2006: Law on gender equality in education. 2006: Domestic violence prevention.
Sources: en.wikipedia.org
Ian Hamley (born 1965) is a British academic who is the Diamond Professor of Physical Chemistry at the University of Reading. He is a soft matter scientist and physical chemist with research expertise in self-assembling molecules including polymers, peptides and other biomolecules. He has more than 400 published scientific papers. He is the author of 'The Physics of Block Copolymers', 'Introduction to Soft Matter', 'Block Copolymers in Solution', 'Introduction to Peptide Science', and 'Small-Angle Scattering: Theory, Instrumentation, Data and Applications', as well as several edited texts.
Naram-Sin defeated Manium of Magan, and various northern hill tribes in the Zagros, Taurus, and Amanus Mountains, expanding his empire up to the Mediterranean Sea. His "Victory Stele" depicts his triumph over Satuni, chief of Lullubi in the Zagros Mountains. The Sumerian King List gives the length of his reign as 56 years, and at least 20 of his year-names are known, referring to military actions against various places such as Uruk and Subartu. One unknown year was recorded as "the Year when Naram-Sin was victorious against Simurrum in Kirasheniwe and took prisoner Baba the governor of Simurrum, and Dubul the ensi of Arame". Other year names refer to his construction work on temples in Akkad, Nippur, and Zabala. He also built administrative centers at Nagar and Nineveh. In general it is not possible to assign an order to Naram-Sin's year name with the exception of his first "The year Naram-Sin received a weapon of heaven/An fr[om] the temple of the god Enlil". It is, however, possible to divide them into those before his deification and after that event (assumed to be shortly after the "Great Revolt") based on the presence of a godhood determinant in his name. During his reign Naram-Sin increased direct royal control of its city-states. He maintained control over the various city-states by the simple expedient of appointing some of his many sons as key provincial governors, and his daughters as high priestesses. He also reformed the scribal system. A few loyal local governors remained in place.
== Wife of the heir to Austrian throne == At this time, Archduke Charles was in his twenties and did not expect to become emperor for some time, especially while Franz Ferdinand remained in good health. This changed on 28 June 1914 when the heir and his wife Sophie were assassinated in Sarajevo by Bosnian Serb nationalists. Charles and Zita received the news by telegram that day. She said of her husband, "Though it was a beautiful day, I saw his face go white in the sun." In the war that followed, Charles was promoted to General in the Austro-Hungarian army, taking command of the 20th Corps for an offensive in Tyrol. The war was personally difficult for Zita, as several of her brothers fought on opposing sides in the conflict (Prince Felix and Prince René had joined the Austrian army, while Prince Sixtus and Prince Xavier lived in France before the war and enlisted in the Belgian army.) Also her country of birth, Italy, joined the war against Austria in 1915, and so rumours of the 'Italian' Zita began to be muttered. Even as late as 1917, the German ambassador in Vienna, Count Botho von Wedel-Jarlsberg, would write to Berlin saying "The Empress is descended from an Italian princely house... People do not entirely trust the Italian and her brood of relatives." At Franz Joseph's request, Zita and her children left their residence at Schloss Hetzendorf and moved into a suite of rooms at Schönbrunn Palace. Here, Zita spent many hours with the old Emperor on both formal and informal occasions, where Franz Joseph confided in her his fears for the future.
Sources: en.wikipedia.org
Registered medical products are most often 0.1% nasal drops. Research suppliers ship lyophilized powder, usually in milligram quantities, which is dissolved before use. The active peptide is the same in both cases; presentation and excipients differ.
No. The peptide is synthetic, although it is modelled on a fragment of a naturally occurring hormone. ACTH(4-10) is generated when ACTH is cleaved, but the Pro-Gly-Pro extension is not a known endogenous sequence. It is therefore a designed analogue rather than a natural metabolite.
The label reflects reported effects on attention, memory and recovery after neurological injury in regional clinical reports. Those reports are mostly small and have not been widely replicated outside the region. The classification is descriptive and does not imply a single defined mechanism.
Dry powder is usually kept at about -20 degrees Celsius for long-term storage and at 2 to 8 degrees Celsius for short working periods. Containers should stay sealed and protected from light and moisture to limit degradation.