nasal formulation comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Last reviewed on 2026-08-01. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
Published studies examine a fairly narrow set of endpoints. Rodent experiments commonly measure maze learning, infarct volume after induced ischemia, and tissue levels of neurotrophic factors. Clinical reports from Russian centres describe attention, memory and recovery scores in patients after stroke or transient ischemic attack. Most of those human studies are small and few have been repeated by independent groups. Outcome measures differ between studies, which limits direct comparison.
Circulation time for the peptide is short because peptidases cleave it readily. The Pro-Gly-Pro tail is thought to slow breakdown compared with the bare ACTH fragment, but the gain appears modest. Absorption after intranasal dosing is limited, and only a fraction of a dose is expected to reach the central nervous system. Laboratory concentrations therefore sit well above levels achieved systemically, a gap that complicates translation from bench findings to clinical claims.
| 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 |
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 parent fragment ACTH(4-10) carries the sequence Met-Glu-His-Phe-Arg-Trp-Gly. Semax replaces the arginine and tryptophan positions with a proline-glycine-proline tail, giving Met-Glu-His-Phe-Pro-Gly-Pro. That change removes residues associated with adrenal stimulation, so the peptide does not drive cortisol release the way full ACTH does. This distinction shapes how the compound is grouped in the literature, where it sits with neuropeptides and peptide neuromodulators rather than with corticosteroids.
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.
Dissolution is normally performed in water, phosphate-buffered saline, or normal saline, since the peptide is freely soluble in aqueous media and is rarely handled with strong organic solvents. Solution pH should be kept near neutral, because extreme acidity or alkalinity accelerates backbone hydrolysis and encourages oxidation of the methionine side chain. Once dissolved, the material is less stable than the dry powder and is commonly divided into single-use portions and frozen. Buffers containing primary amines, such as Tris, are often avoided because of possible side reactions.
Back pain (Latin: dorsalgia) is pain felt in the back. It may be classified as neck pain (cervical), middle back pain (thoracic), lower back pain (lumbar) or coccydynia (tailbone or sacral pain) based on the segment affected. The lumbar region is the most commonly affected area. An episode of back pain may be acute, subacute or chronic depending on the duration. The pain may be characterized as a dull ache, shooting or piercing pain or a burning sensation. Discomfort can radiate to the arms and hands as well as the legs or feet, and may include numbness or weakness in the legs and arms. The majority of back pain is nonspecific and idiopathic. Common underlying mechanisms include degenerative or traumatic changes to the discs and facet joints, which can then cause secondary pain in the muscles and nerves and referred pain to the bones, joints and extremities. Diseases and inflammation of the gallbladder, pancreas, aorta and kidneys may also cause referred pain in the back. Tumors of the vertebrae, neural tissues and adjacent structures can also manifest as back pain. Back pain is common; approximately nine of ten adults experience it at some point in their lives, and five in ten working adults are affected each year. Some estimate that as many of 95% of people will experience back pain at some point in their lifetime. It is the most common cause of chronic pain and is a major contributor to missed work and disability. For most individuals, back pain is self-limiting.
=== Mass photometry === Mass photometry (MP) is a rapid, in-solution, label-free method of obtaining the molecular mass of proteins, lipids, sugars and nucleic acids at the single-molecule level. The technique is based on interferometric scattered light microscopy. Contrast from scattered light by a single binding event at the interface between the protein solution and glass slide is detected and is linearly proportional to the mass of the molecule. This technique can also be used to measure sample homogeneity, to detect protein oligomerisation states, and to identify complex macromolecular assemblies (ribosomes, GroEL, AAV) and protein interactions such as protein-protein interactions. Mass photometry can accurately measure molecular mass over a wide range of molecular masses (40 kDa – 5 MDa).
=== Economics === Estimated costs for a 12-week treatment of elbasvir/grazoprevir are upwards of $54,600. Other treatments that work in a similar manner have effectively more costs. Some treatments for Hepatitis C are on the cheaper side, in some instances as low as $8,400. Additional ribavirin costs can add between $500 and $900. These cheaper prescriptions are however interferon-based treatments and do not target every genotype of the HCV. These regimens were the priority treatment before 2011. Two examples of these treatments are alfa-2a and alfa-2b costing $9250 and $8400, respectively.
At least one study indicates that individuals with a DSD condition may be more prone to psychological difficulties, due at least in part to parental attitudes and behaviors, and concludes that preventative long-term psychological counseling for parents as well as for affected individuals should be initiated at the time of diagnosis. A retrospective study shows that the prevalence of anxiety and depressive disorders among CAIS individuals is approximately twice as high as in male referents without DSD, but no evident corresponding difference has been found compared to female referents. Lifespan is not thought to be affected by AIS. Despite the well-developed breasts in CAIS women, and for reasons that are not well-understood, breast cancer has never been reported in CAIS women and does not seem to occur or occurs only rarely. Only one case report of juvenile fibroadenoma exists. A few cases of breast cancer have been reported in individuals with partial androgen insensitivity syndrome. In contrast to bone health, both transdermal estradiol treatment and testosterone treatment in women with CAIS results in worsening in lipid profiles. A case report in 2009 also shows that CAIS individuals with intact testes (with endogenous hormone) are more likely to be obese. A study which includes five CAIS and two PAIS adolescents with ages ranging from 15 to 24 shows elevated homeostatic model assessment for insulin resistance (HOMA-IR) scores for all subjects.
Sources: en.wikipedia.org
Towards the end of this period the pro-independence forces made two important advances. In the Southern Cone, a veteran of the Spanish army with experience in the Peninsular War, José de San Martín, became the governor of the Province of Cuyo. He used this position to begin organizing an army as early as 1814 in preparation for an invasion of Chile. This was an important change in strategy after three United Provinces campaigns had been defeated in Upper Peru. San Martín's army became the nucleus of the Army of the Andes, which received crucial political and material support in 1816 when Juan Martín de Pueyrredón became Supreme Director of the United Provinces. In January 1817, San Martín was finally ready to advance against the royalists in Chile. Ignoring an injunction from the congress of the Río de la Plata not to move against Chile, San Martín together with General Bernardo O'Higgins Riquelme, later Supreme Director of Chile, led the Army over the Andes in a move that turned the tables on the royalists. By 10 February, San Martín had control of northern and central Chile, and a year later, after a war with no quarter, the south. With the aid of a fleet under the command of former British naval officer Thomas Cochrane, Chile was secured from royalist control and independence was declared that year. San Martín and his allies spent the next two years planning an invasion of Peru, which began in 1820.
The production of pure alkali metals is somewhat complicated due to their extreme reactivity with commonly used substances, such as water. From their silicate ores, all the stable alkali metals may be obtained the same way: sulfuric acid is first used to dissolve the desired alkali metal ion and aluminium(III) ions from the ore (leaching), whereupon basic precipitation removes aluminium ions from the mixture by precipitating it as the hydroxide. The remaining insoluble alkali metal carbonate is then precipitated selectively; the salt is then dissolved in hydrochloric acid to produce the chloride. The result is then left to evaporate and the alkali metal can then be isolated. Lithium and sodium are typically isolated through electrolysis from their liquid chlorides, with calcium chloride typically added to lower the melting point of the mixture. The heavier alkali metals, however, are more typically isolated in a different way, where a reducing agent (typically sodium for potassium and magnesium or calcium for the heaviest alkali metals) is used to reduce the alkali metal chloride. The liquid or gaseous product (the alkali metal) then undergoes fractional distillation for purification. Most routes to the pure alkali metals require the use of electrolysis due to their high reactivity; one of the few which does not is the pyrolysis of the corresponding alkali metal azide, which yields the metal for sodium, potassium, rubidium, and caesium and the nitride for lithium. Lithium salts have to be extracted from the water of mineral springs, brine pools, and brine deposits.
"Chemical Composition of Vintage Preban Absinthe with Special Reference to Thujone, Fenchone, Pinocamphone, Methanol, Copper, and Antimony Concentrations". Journal of Agricultural and Food Chemistry. 56 (9): 3073–3081. Bibcode:2008JAFC...56.3073L. doi:10.1021/jf703568f. PMID 18419128. Lachenmeier, Dirk W.; Walch, Stephan G.; Padosch, Stephan A.; Kröner, Lars U. (2006). "Absinthe – A Review". Critical Reviews in Food Science and Nutrition. 46 (5): 365–377. doi:10.1080/10408690590957322. PMID 16891209. S2CID 43251156.
== Function == Proteins of the OAT family catalyze the Na+-independent facilitated transport of fairly large amphipathic organic anions (and less frequently neutral or cationic drugs), such as bromosulfobromophthalein, prostaglandins, conjugated and unconjugated bile acids (taurocholate and cholate), steroid conjugates, thyroid hormones, anionic oligopeptides, drugs, toxins and other xenobiotics. One family member, OATP2B1, has been shown to use cytoplasmic glutamate as the exchanging anion. Among the well characterized substrates are numerous drugs including statins, angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, antibiotics, antihistaminics, antihypertensives and anticancer drugs. Other substrates include luciferin, thyroid hormones and quinolones. Organic anion transporting polypeptides carry bile acids as well as bilirubin and numerous hormones such as thyroid and steroid hormones across the basolateral membrane (facing sinusoids) in hepatocytes, for excretion in bile. As well as expression in the liver, OATPs are expressed in many other tissues on basolateral and apical membranes, transporting anions, as well as neutral and even cationic compounds. They also transport an extremely diverse range of drug compounds, ranging from anti-cancer, antibiotic, lipid lowering to anti-diabetic drugs, as well as toxins and poisons. Various anti-cancer drugs like pazopanib, vandetanib, nilotinib, canertinib and erlotinib are known to be transported via OATPs (OATP-1B1 and OATP-1B3).
Afterwards, Kan finds photographic evidence taken by Au of Choi and Lee together. Lau's independent team finds the location of Choi's remaining henchmen and the stolen police van. Lee, meanwhile, convinces and bribes several senior police officers to sign a petition for Lau's removal, to which some comply. In the final hours before Lau steps down, he launches a raid on the henchmen, and requests that Lee take command, noting that the henchmen were former renegade police officers who had worked under Lee, as he would understand their strategies. Lee accepts, knowing that he cannot refuse without looking weak. The operation is a success, with all suspects killed. However, with Choi's henchmen dead, this taxes Lee emotionally due to his close friendships. Kan and Lau report Lee's and Choi's crimes to the chief executive, who decides to grant pardon to both men since they are too important to arrest without destabilizing society. Lee is forced into retirement, and Choi is permanently exiled from Hong Kong without returning, with their exact crimes not disclosed to the public. Lau retains his office as commissioner, and Lee visits his son, unconscious and in custody at a hospital bed. Elsewhere, Lai continues his campaign to be elected as the future Chief Executive of Hong Kong, hoping to control the government's politics, leaving more mysteries unsolved.
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 consists mainly of animal experiments and small clinical reports, with much of the clinical material published in Russian-language journals. Large independent trials are scarce. Separating reliable effects from chance findings is consequently difficult.