Semax is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Updated 2025-09-12. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Sequence | Met-Glu-His-Phe-Pro-Gly-Pro | Heptapeptide; ACTH(4-10) analog extended at C-terminus |
| Molecular mass | ~813.9 Da | Free peptide, unmodified |
| Appearance | White to off-white powder | Typical lyophilized solid |
| Solubility | Soluble in water and saline | Also soluble in common aqueous buffers |
| Storage (solid) | -20 °C, desiccated | Protect from moisture and repeated thawing |
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.
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.
Published research on this peptide originates mainly from Russian laboratories, and the wider international literature is comparatively thin. Studies have used rodent models of stroke, hypoxia, and memory tasks, with a smaller number of human trials reported. Reported outcomes include changes in attention and memory measures, along with effects on neurotrophic factor expression in some experiments. Small sample sizes, inconsistent dosing protocols, and limited independent replication are widely noted limitations, so the strength of the clinical evidence remains an open question.
Hydride-dependent reactions: in nature the ERs promote an hydride attack on the β-carbon of an activated (C═C) bond modificating its electronic density. This catalytic abilty promotes the reduction of other functional groups of a variety of non-natural subtrates, including the hydrogenation of nitro groups, activated oximes, activated alkynes, and α,β-dicarbonyls, as well as the desaturation of α,β-saturated carbonyl compounds. Hydride-independent reactions: ERs can catalyze reactions relyng on an external source of electrons to reduce the flavin cofactor, thereby initiating the reaction cycle. Otherwise, a desaturation reaction can rely on substrate reduction of flavin to promote the catalytic cycle. However not all the hydride-independent reactions mechanistically depend on the flavin cofactor or the involvement of the hydride transfer process. Some examples of these reactions are the (C═C) bond isomerization, Knoevenagel condensation, Morita–Baylis–Hillman reaction, and radical reactions.
Urea labeled with carbon-14 or carbon-13 is used in the urea breath test, which is used to detect the presence of the bacterium Helicobacter pylori (H. pylori) in the stomach and duodenum of humans, associated with peptic ulcers. The test detects the characteristic enzyme urease, produced by H. pylori, by a reaction that produces ammonia from urea. This increases the pH (reduces the acidity) of the stomach environment around the bacteria. Similar bacteria species to H. pylori can be identified by the same test in animals such as apes, dogs, and cats (including big cats).
== External links == Human ANG genome location and ANG gene details page in the UCSC Genome Browser. Human RNASE4 genome location and RNASE4 gene details page in the UCSC Genome Browser. Human AMOT genome location and AMOT gene details page in the UCSC Genome Browser. Overview of all the structural information available in the PDB for UniProt: P03950 (Human Angiogenin) at the PDBe-KB. Overview of all the structural information available in the PDB for UniProt: P21570 (Mouse Angiogenin) at the PDBe-KB.
=== Response to 2022 Russian invasion of Ukraine === During the 2022 Russian invasion of Ukraine, Medtronic refused to join the international community and withdraw from the Russian market. Research from Yale University updated on 28 April 2022, identifying how companies were reacting to Russia's invasion identified Medtronic in the worst category of "Digging In" ("F" rank), meaning Defying Demands for Exit: companies defying demands for exit/reduction of activities. As of June 2, 2025, Medtronic's standing has improved slightly, now identified in the "Buying Time" ("D" rank) category, meaning Holding Off New Investments/Development: companies postponing future planned investment/development/marketing while continuing substantive business.
Sources: en.wikipedia.org
=== Wastewater treatment === A majority of silver nanoparticles in consumer products go down the drain and are eventually released into sewer systems and reach wastewater treatment plants. Primary screening and grit removal in wastewater treatment does not completely filter out silver nanoparticles, and coagulation treatment may lead to further condensation into wastewater sludge. The secondary wastewater treatment process involves suspended growth systems which allow bacteria to decompose organic matter within the water. Any silver nanoparticles still suspended in the water may collect on these microbes, potentially killing them due to their antimicrobial effects. After passing through both treatment processes, the silver nanoparticles are eventually deposited into the environment. A majority of the submerged portions of wastewater treatment plants are anoxic and rich in sulfur. During the wastewater treatment process, silver nanoparticles either remain the same, are converted into free silver ions, complex with ligands, or agglomerate. Silver nanoparticles can also attach to wastewater biosolids found in both the sludge and the effluent. Silver ions in wastewater are removed efficiently because of their strong complexation with chloride or sulfide. A majority of the silver found in wastewater treatment plant effluent is associated with reduced sulfur as organic thiol groups and inorganic sulfides. Silver nanoparticles also tend to accumulate in activated sludge, and the dominant form of the silver found in sewage sludge is Ag2S.
fingerprick type of glucose meter - need to prick self finger 8-12 times a day. continuous glucose monitor - the CGM monitors the glucose levels every 5 minutes approximately. Laboratory tests are often used to diagnose illnesses and such methods include
an intermediate or building block in the synthesis of non-ionic and other surfactants and related functional additives; a component of lubricant and plastic additive systems, including thermoplastic polyurethanes, where long-chain alcohols are used to modify flexibility and permeability; a minor constituent of policosanol-type mixtures employed in cosmetics and personal-care products as part of the lipid phase of creams and emulsions. Because of its chain length and structural similarity to other fatty alcohols, 1-heneicosanol is also used as a reference compound and analytical standard in studies of plant waxes, policosanol mixtures and related lipid fractions. Available safety data sheets describe 1-heneicosanol as a low-volatility solid that is not classified as hazardous under European CLP regulations, but which may cause mild irritation to the skin, eyes and respiratory tract on contact or inhalation of dust. Standard laboratory precautions such as avoiding dust formation, using local exhaust ventilation and wearing eye and skin protection are recommended.
The common class of antifungal drugs known as azoles disrupts the fungal sterol biosynthesis pathway, upstream of C-5 sterol desaturase leading to the accumulation of nontoxic 14α-methylated sterols. C5SD then converts these intermediates into a toxic product. Consequently, in both the pathogenic fungus Candida albicans and model organism S. cerevisiae mutations in the gene encoding C-5 sterol desaturase (ERG3) allow the cell to avoid synthesizing the toxic sterol products and have been shown to confer azole resistance. In at least the case of fluconazole, antifungal resistance due to C5SD inactivation is dependent on the activity of the chaperone protein Hsp90 and the phosphatase calcineurin. However, the clinical relevance of this azole resistance mechanism is controversial because while the deletion of ERG3 alone confers fluconazole resistance to C. albicans in vitro, it is insufficient to confer fluconazole resistance in a live mouse model.
CCL7 was first characterized from osteosarcoma supernatant. CCL7 consists of 99 amino acids, which contains 23-amino acid signal peptide. The mature protein about 76 amino acids is secreted after cleavage of the signal peptide. In contrast to most chemokines, CCL7 exists in a general monomeric form, differing from the dimer formed in a highly concentrated solution. CCL7 can exist in four different glycotypes with a molecular weight 11, 13, 17 and 18 kDa in COS cells. CCL7 mediates effects on the immune cell types through binding to numerous receptors, including CCR1, CCR2, CCR3, CCR5, and CCR10. These receptors belongs to the G protein-coupled seven-transmembrane receptors. CCL7 can also interact with cell surface glycosaminoglycans (GAGs) present on all animal cell surfaces.
Sources: en.wikipedia.org
Carbohydrate synthesis is a sub-field of organic chemistry concerned with generating complex carbohydrate structures from simple units (monosaccharides). The generation of carbohydrate structures usually involves linking monosaccharides or oligosaccharides through glycosidic bonds, a process called glycosylation. Therefore, it is important to construct glycosidic linkages that have optimum molecular geometry (stereoselectivity) and the stable bond (regioselectivity) at the reaction site (anomeric centre).
=== Radionuclide === As 241Am has a half-life roughly similar to 238Pu (432.2 years vs. 87 years), it has been proposed as an active element of radioisotope thermoelectric generators, for example in spacecraft. Although americium produces less heat and electricity – the power yield is 114.7 mW/g for 241Am and 6.31 mW/g for 243Am (cf. 390 mW/g for 238Pu) – and its radiation poses more threat to humans owing to neutron emission, the European Space Agency is considering using americium for its space probes. Another proposed space-related application of americium is a fuel for space ships with nuclear propulsion. It relies on the very high rate of nuclear fission of 242mAm, which can be maintained even in a micrometer-thick foil. Small thickness avoids the problem of self-absorption of emitted radiation. This problem is pertinent to uranium or plutonium rods, in which only surface layers provide alpha-particles. The fission products of 242mAm can either directly propel the spaceship or they can heat a thrusting gas. They can also transfer their energy to a fluid and generate electricity through a magnetohydrodynamic generator. One proposal which utilizes the high nuclear fission rate of 242mAm is a nuclear battery. Its design relies not on the energy emitted by americium alpha particles but on their charge. In this way the americium acts as a self-sustaining cathode. A single 3.2 kg 242mAm charge of such a battery could provide about 140 kW of power over a period of 80 days.
== Approval == Pramlintide has been approved on 3/16/2005 by the FDA, for use by type 1 and type 2 diabetic patients who use insulin.(subscription required) Pramlintide allows patients to use less insulin, lowers average blood sugar levels, and substantially reduces what otherwise would be a large unhealthy rise in blood sugar that occurs in diabetics right after eating. Apart from insulin analogs, pramlintide is the only drug approved by the FDA to lower blood sugar in type 1 diabetics since insulin in the early 1920s.
In general, the Houthis' political ideology has gradually shifted from "heavily-religious mobilisation and activism under Husayn to the more assertive and statesmanlike rhetoric under Abdulmalik", its current leader. With strong support from Houthis from the predominantly Zaydi northern tribes, the Houthi movement has often been described as a tribalist or monarchist faction in opposition to republicanism. Regardless, they have managed to rally many people outside of their traditional bases to their cause and have become a major nationalist force.
Sources: en.wikipedia.org
Semax is a synthetic seven-amino-acid peptide derived from a fragment of corticotropin. It is used in Russia as a nasal preparation, while elsewhere it is studied as a research compound. It is not approved as a medicine in most countries.
Its sequence corresponds to the 4-10 region of corticotropin extended by three residues. This fragment lacks the region responsible for adrenal steroid release, so it is explored for neural rather than hormonal effects. The relationship explains the compound's classification among ACTH-derived peptides.
It holds approval in Russia for several neurological indications as a nasal spray or drop formulation. Regulatory agencies in the United States and the European Union have not approved it. Products sold elsewhere are generally labeled for research use only.
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.