heptapeptide 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 2025-08-15 and is reviewed periodically as new material appears.
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.
The compound is registered in Russia as a pharmaceutical product, most commonly formulated as a nasal solution, and has been used in that setting since the 1990s. Outside that jurisdiction it is generally handled as a research chemical rather than an approved medicine. Regulatory status therefore differs sharply between countries, and material sold internationally may not correspond to the Russian pharmaceutical formulation. Documentation with commercial samples is typically limited to a certificate of analysis covering purity and identity, not clinical status or local legal classification.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It corresponds to the ACTH(4-7) fragment extended at the C-terminus by a Pro-Gly-Pro tripeptide, an addition intended to slow enzymatic breakdown. The molecular formula is C37H51N9O10S and the molecular mass is approximately 814 daltons. In the literature it is often described as an ACTH(4-10) analog, although that label reflects a naming convention as much as a precise structural relationship. The compound was developed in Russia and remains most closely associated with that research tradition.
| 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 |
Russian regulatory authorities approved the peptide for nasal administration, and it remains listed in the national pharmacopoeia under several trade names. Documented indications include acute ischemic stroke, transient ischemic attacks, traumatic brain injury, and certain ophthalmological and neurological conditions. Physicians also prescribe it for cognitive complaints in older patients, although the evidence base for that use is thinner. Outside Russia and a few neighboring states, the substance is not an approved medicine and is sold instead as a research chemical.
Later generations of the molecule include an N-acetylated form and an amidated form, both marketed online alongside the parent peptide. These variants differ in terminal chemistry and stability, and they are frequently discussed in the same breath even though they have not been compared in controlled trials. Supply outside formal healthcare systems comes largely from laboratories that synthesize peptides to order. Purity and identity of these materials vary widely, and no single body oversees the international trade.
Semax is a synthetic heptapeptide developed in the Soviet Union during the 1980s by researchers at the Institute of Molecular Genetics in Moscow. It was designed as a truncated analog of adrenocorticotropic hormone, retaining only the fragment spanning residues four through ten. Investigators sought a peptide that would preserve the cognitive effects associated with ACTH while eliminating the hormonal stimulation of the adrenal cortex. The compound entered clinical use in Russia during the following decade.
=== Post-RDS-1 === In the subsequent years it became increasingly valuable to gather information on the Soviet nuclear weapons program, which resulted in the development of technologies that could gather airborne particles in a WB-29 weather reconnaissance plane. On September 3, 1949, these particles were used to determine that the detonation time of the first Soviet atomic test, "Joe 1". Further analysis revealed that this bomb was a replicate of the "Fat Man", which was the bomb dropped on Nagasaki in 1945. This investigative methodology combined radiochemistry and other techniques to gather intelligence on nuclear activities. During the 1961 Soviet nuclear tests, most of the Novaya Zemlya shots were likely monitored by RB-47 aircraft flown from RAF Brize Norton and elsewhere. In August, Khrushchev had announced the existence 100 megaton Soviet bomb, ultimately tested as the Tsar Bomba. A JKC-135A was rapidly outfitted to monitor the test, under Operation Speed Light Bravo. Photomutiplier detectors in UV, visibile, and near-IR were used, with multiplication factors above 100 million. Cine and stills cameras were used, with lens resolutions up to 70 mm. One side of the aircraft was scorched. It has been argued that if the Tsar Bomba had been configured to yield 100 megatons instead of the decided 50, that the aircraft would have been destroyed. The United Kingdom worked with the US to monitor Soviet tests. RAF debris collection missions flew from the summer of 1949 from Scotland, Northern Ireland, and Gibraltar, filling the North Atlantic.
== Medical uses == Vericiguat is indicated to reduce the risk of cardiovascular death and hospitalization for heart failure following a prior hospitalization for heart failure or need for outpatient intravenous diuretics, in adults with symptomatic chronic heart failure and an ejection fraction of less than 45% (HFrEF). Vericiguat is usually given orally once every day with food. No dose adjustments are required in the elderly, in people with mild-to-moderate liver failure, or in those with impaired kidney function. As of 2024, no studies have found information for patients with severely impaired kidney function, severe liver failure, or are on dialysis. Vericiguat is contraindicated in pregnancy. While there are no studies on its safety when used by pregnant women, animals studies suggest higher rates of birth defects, as well as increased number of abortions and resorptions. It may also pass into breast milk, but the effects on breastfed infants is unknown. The manufacturer advises that child-bearing age patients should be on contraception and assessed for pregnancy before starting treatment.
During the 1970s Denmark was plunged into a crisis, initiated by the 1973 oil crisis leading to the hitherto unknown phenomenon stagflation. For the next decades the Danish economy struggled with several major so-called "balance problems": High unemployment, current account deficits, inflation, and government debt. From the 1980s economic policies have increasingly been oriented towards a long-term perspective, and gradually a series of structural reforms have solved these problems. In 1994 active labour market policies were introduced that via a series of labour market reforms have helped reducing structural unemployment considerably. A series of tax reforms from 1987 onwards, reducing tax deductions on interest payments, and the increasing importance of compulsory labour market-based funded pensions from the 1990s have increased private savings rates considerably, consequently transforming secular current account deficits to secular surpluses. The announcement of a consistent and hence more credible fixed exchange rate in 1982 has helped reducing the inflation rate. In the first decade of the 21st century new economic policy issues have emerged. A growing awareness that future demographic changes, in particular increasing longevity, could threaten fiscal sustainability, implying very large fiscal deficits in future decades, led to major political agreements in 2006 and 2011, both increasing the future eligibility age of receiving public age-related pensions.
== ERLIC == ERLIC (electrostatic repulsion interaction chromatography) is a type of HILIC that relies on electrostatic interactions, coined by Alpert in 2008. The ionic stationary phase in ERLIC is chosen to have a similar charge to the analyte(s) so that the analyte is repelled by the stationary phase but also retained by the aqueous layer, allowing for enhanced interaction of the remaining polar, oppositely-charged functional groups of the analyte. Electrostatic effects have an order of magnitude stronger chemical potential than neutral polar effects. These opposing effects can, in some cases, enable isocratic separations, with the mobile phase held constant instead of delivered at a gradient. ERLIC can be used to reduce retention of more polar functional groups and minimize the influence of common ionic groups within a set of analytes.
The ancestors of bacteria were unicellular microorganisms that were the first forms of life to appear on Earth, about 4 billion years ago. For about 3 billion years, most organisms were microscopic, and bacteria and archaea were the dominant forms of life. Although bacterial fossils exist, such as stromatolites, their lack of distinctive morphology prevents them from being used to examine the history of bacterial evolution, or to date the time of origin of a particular bacterial species. However, gene sequences can be used to reconstruct the bacterial phylogeny, and these studies indicate that bacteria diverged first from the archaeal/eukaryotic lineage. The most recent common ancestor (MRCA) of bacteria and archaea was probably a hyperthermophile that lived about 2.5 billion–3.2 billion years ago. The earliest life on land may have been bacteria some 3.22 billion years ago. Bacteria were also involved in the second great evolutionary divergence, that of the archaea and eukaryotes. Here, eukaryotes resulted from the entering of ancient bacteria into endosymbiotic associations with the ancestors of eukaryotic cells, which were themselves possibly related to the Archaea. This involved the engulfment by proto-eukaryotic cells of alphaproteobacterial symbionts to form either mitochondria or hydrogenosomes, which are still found in all known Eukarya (sometimes in highly reduced form, e.g. in species of amitochondrial protozoa).
Sources: en.wikipedia.org
Selecting the linear velocity is therefore the same compromise between the level of separation and length of analysis as selecting the column temperature. The linear velocity will be implemented by means of the carrier gas flow rate, with regards to the inner diameter of the column. With GCs made before the 1990s, carrier flow rate was controlled indirectly by controlling the carrier inlet pressure, or "column head pressure". The actual flow rate was measured at the outlet of the column or the detector with an electronic flow meter, or a bubble flow meter, and could be an involved, time consuming, and frustrating process. It was not possible to vary the pressure setting during the run, and thus the flow was essentially constant during the analysis. The relation between flow rate and inlet pressure is calculated with Poiseuille's equation for compressible fluids. Many modern GCs, however, electronically measure the flow rate, and electronically control the carrier gas pressure to set the flow rate. Consequently, carrier pressures and flow rates can be adjusted during the run, creating pressure/flow programs similar to temperature programs.
=== Brazil === Stroganoff is a popular dish in Brazil, where it is known as estrogonofe or strogonoff. Estrogonofe is generally prepared with tomato paste or ketchup and mushrooms. Chicken is sometimes used instead of beef. Estrogonofe is generally eaten with cooked white rice and shoestring fries (batata palha).
In August 2008, Eli Lilly purchased the right to manufacture bovine somatotropin (bovine growth hormone), used to increase milk production in dairy cattle, from Monsanto. Use of the supplement has become controversial due to the animal ethics and human health concerns.
Heparin-binding EGF-like growth factor (HB-EGF) transforming growth factor-α (TGF-α) Amphiregulin (AR) Epiregulin (EPR) Epigen Betacellulin (BTC) neuregulin-1 (NRG1) neuregulin-2 (NRG2) neuregulin-3 (NRG3) neuregulin-4 (NRG4). All family members contain one or more repeats of the conserved amino acid sequence: CX7CX4-5CX10-13CXCX8GXRC Where C is cysteine, G is glycine, R is arginine, and X represents any amino acid. This sequence contains six cysteine residues that form three intramolecular disulfide bonds. Disulfide bond formation generates three structural loops that are essential for high-affinity binding between members of the EGF-family and their cell-surface receptors.
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.
It is registered as a pharmaceutical product in Russia, where it is typically supplied as a nasal solution. In most other countries it is not an approved drug and is traded as a research chemical instead. Approval status depends entirely on the jurisdiction involved.