Semax 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 2026-04-08 and is reviewed periodically as new material appears.
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.
Pharmacological accounts link semax to melanocortin signalling and to modulation of neurotrophic factor expression, particularly brain-derived neurotrophic factor and nerve growth factor. Much of this evidence comes from rodent studies using intranasal delivery, a route chosen because it allows peptides to reach the central nervous system with limited systemic exposure. Whether the same mechanisms operate in humans at comparable magnitude remains an open question. The precise receptor or receptors responsible for the reported behavioural and neuroprotective effects have not been conclusively identified.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Its chain combines the first seven residues of corticotropin with a C-terminal proline-glycine-proline extension, a modification intended to slow enzymatic breakdown. The free peptide has a molecular mass near 813.9 daltons. It belongs to the class of ACTH-derived fragments studied for central nervous system activity rather than for adrenal steroid stimulation. This structural relationship to a natural hormone fragment is the usual starting point for describing the compound in the literature.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Free acid form of the heptapeptide; depends on terminal groups |
| Molecular mass | About 813.9 g/mol | Average mass used for mass spectrometry confirmation |
| Appearance | White to off-white solid | Supplied as a lyophilised powder; hygroscopic |
| Solubility class | Freely soluble in aqueous media | Water, saline, and phosphate buffers; limited organic solubility |
| Typical storage temperature | -20 degrees Celsius | Long term and dry; short working periods may use 2 to 8 degrees Celsius |
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.
The proposed mechanism centres on neurotrophic signalling rather than direct receptor activation. Semax is reported to increase expression of brain-derived neurotrophic factor and nerve growth factor in several brain regions, and to shift the balance between excitatory and inhibitory neurotransmitter systems. Interaction with melanocortin receptors has been suggested because of the parent ACTH fragment. Many of these findings come from rodent studies, and the extent to which they translate to human physiology remains an open question.
Semax 是人工设计的七肽，序列为 Met-Glu-His-Phe-Pro-Gly-Pro，骨架取自促肾上腺皮质激素片段 ACTH(4-10)。它于二十世纪八十年代在苏联的分子遗传学研究机构内合成。设计目标是保留该片段与注意力和记忆相关的活性，同时剔除促皮质激素释放等内分泌作用。此后俄罗斯将其登记为药品并进入临床使用。
当时的短肽研究普遍关注能否穿越血脑屏障、在低剂量下产生中枢效应，Semax 属于这一路线。鼻内给药是其主要使用方式，俄语文献报道的适应症涵盖缺血性卒中、短暂性脑缺血发作、认知功能减退以及视神经病变。这些研究大多发表在当地期刊上，样本规模与终点设置同西方试验惯例存在差异，国际同行对其临床证据的强度看法不一。
Pakistani forces under "Operation 11 Garaj" killed 10 TTP militants, eight in the Darbi Khel and Batan areas of Khyber District and two in Shakro area of Bajaur district. Eight more militants of HGB groups were killed in an attempt to infiltrate the Pakistan-Afghanistan border in the Datta Khel area of North Waziristan. Pakistan also claimed to have killed a senior TTP commander, Amir Muawiya during an operation (IBO) in Chapri Naryab area of Hangu District. Two insurgents including a suicide bomber were killed by the military in the Hundi Khel area of Bannu District. An IED attack on a police vehicle in Peshawar wounded two personnel, while an attempted ambush on a police convoy in Boya Tehsil led to no casualties. On 3 August, a cleric Mufti Jan Mir, was killed in an explosion in Wana, likely carried out by TTP. A mortar strike by militants on a nomadic camp in Ahmadwam area of Sararogha tehsil killed three and wounded five. Police repelled an attempted militant assault on the Kharai Dara Police Post in Ambar tehsil. A TTP insurgent was killed in an operation in Bara Tehsil while two Lashkar-e-Islam insurgents were killed in Bhutan Sharif area of Tirah Valley. Three militants were killed in a military operation in Lakki Marwat District while two were killed in a police encounter in Peshawar. TTP attacked and damaged a United Bank Limited branch in Dallan area of Hangu District kidnapping two employees. On 5 August, a mortar strike in the Shaktoi Shaga Anay Khel area of South Waziristan wounded a civilian.
Highly innervated, the clitoral glans (glans means "acorn" in Latin), also known as the "head" or "tip", exists at the anterior side of the clitoral body as a fibro-vascular cap and is usually the size and shape of a pea, although it is sometimes much larger or smaller. The glans is separated from the clitoral body by a ridge of tissue called the corona. The clitoral glans is estimated to have 8,000 and possibly 10,000 or more sensory nerve endings, making it the most sensitive erogenous zone. The glans also has numerous genital corpuscles. Research conflicts on whether the glans is composed of erectile or non-erectile tissue. Some sources describe the clitoral glans and labia minora as composed of non-erectile tissue; this is especially the case for the glans. They state that the clitoral glans and labia minora have blood vessels that are dispersed within a fibrous matrix and have only a minimal amount of smooth muscle, or that the clitoral glans is "a midline, densely neural, non-erectile structure". The clitoral glans is homologous to the male penile glans. Other descriptions of the glans assert that it is composed of erectile tissue and that erectile tissue is present within the labia minora. The glans may be noted as having glandular vascular spaces that are not as prominent as those in the clitoral body, with the spaces being separated more by smooth muscle than in the body and crura. Adipose tissue is absent in the labia minora, but the organ may be described as being made up of dense connective tissue, erectile tissue and elastic fibers.
==== Inositol ==== Inositol, a sugar alcohol in fruits, beans, grains and nuts, was found to be significantly better than placebo in treating depression in a double-blind, controlled trial. It was also reported to be reduced in human CSF in depression and found to lead to "major improvement" in 9 of 11 depressed patients in an open label trial.
Sources: en.wikipedia.org
The Aviation and Transportation Security Act made the federal government, rather than airports, responsible for airport security. The law created the Transportation Security Administration to inspect passengers and luggage, causing long delays and concern over passenger privacy. After suspected abuses of the USA Patriot Act were brought to light in June 2013 with articles about the collection of American call records by the NSA and the PRISM program, Representative Jim Sensenbrenner (of Wisconsin), who introduced the Patriot Act in 2001, said that the NSA overstepped its bounds. Criticism of the war on terror has focused on its morality, efficiency, and cost. According to a 2021 report by the Costs of War Project, the several post-9/11 wars participated in by the United States in its war on terror have caused the displacement, conservatively calculated, of 38 million people in Afghanistan, Pakistan, Iraq, Libya, Syria, Yemen, Somalia, and the Philippines. They estimated these wars caused the deaths of 897,000 to 929,000 people directly and cost US$8 trillion. In a 2023 report, the Costs of War Project estimated that there have been between 3.6 and 3.7 million indirect deaths in the post-9/11 war zones, with the total death toll being 4.5 to 4.6 million. The report defined post-9/11 war zones as conflicts that included significant United States counter-terrorism operations since 9/11, which in addition to the wars in Iraq, Afghanistan and Pakistan, also includes the civil wars in Syria, Yemen, Libya and Somalia.
DNA vaccines have been introduced into animal tissues by multiple methods. In 1999, the two most popular approaches were injection of DNA in saline: by using a standard hypodermic needle, or by using a gene gun delivery. Several other techniques have been documented in the intervening years.
The report published by the committee noted that while methadone itself was potentially addictive, it produced "considerably" less euphoria, sedation, and respiratory depression than morphine at equianalgesic doses and was thus interesting as a commercial drug. The same report also compared methadone to pethidine. German researchers reported that methadone was capable of producing strong morphine-like physical dependence, which is characterized by opioid withdrawal symptoms which are lesser in severity and intensity compared to morphine, but methadone was associated with a considerably prolonged or protracted withdrawal syndrome when compared to morphine. Morphine produced higher rates of self-administration and reinforcing behaviour in both human and animal subjects when compared to both methadone and pethidine. In comparison to equianalgesic doses of pethidine (Demerol), methadone was shown to produce less euphoria, but higher rates of constipation, and roughly equal levels of respiratory depression and sedation. In the early 1950s, methadone (most times the racemic HCl salts mixture) was also investigated for use as an antitussive. Isomethadone, noracymethadol, LAAM, and normethadone were first developed in Germany, the United Kingdom, Belgium, Austria, Canada, and the United States in the thirty or so years after the 1937 discovery of pethidine, the first synthetic opioid used in medicine.
Sources: en.wikipedia.org
== System overview == In vertebrates, limb position and velocity are encoded by muscle spindle group Ia afferents responding to muscle length and velocity and muscle spindle group II afferents responding mainly to muscle length. There is a similar division of encoding in invertebrates; different subgroups of neurons of the chordotonal organ encode limb position and velocity. Load on a limb is signaled by Golgi tendon organs: type Ib afferents. These proprioceptors respond to the force a muscle is exerting. Similarly, invertebrates have a mechanism to determine limb load: the campaniform sensilla. These proprioceptors are active when a limb experiences resistance. A third role for proprioceptors is to determine when a joint is at a specific position. In vertebrates, this is accomplished by Ruffini endings and Pacinian corpuscles. These proprioceptors are activated when the joint is at a threshold position, usually at the extremes of joint position. Invertebrates use hair plates to accomplish this; a field of bristles located within joints that detects the relative movement of limb segments through the deflection of the associated cuticular hairs.
MIL-53 MOFs possess a "wine rack" structure. These MOFs have been explored for anisotropy in Young's modulus due to the flexibility of loading, and the potential for negative linear compressibility when compressing in one direction, due to the ability of the wine rack opening during loading.
the non-standard amino acid to encode, an unused codon to adopt, a tRNA that recognizes this codon, and a tRNA synthetase that recognizes only that tRNA and only the non-standard amino acid. Expanding the genetic code is an area of research of synthetic biology, an applied biological discipline whose goal is to engineer living systems for useful purposes. The genetic code expansion enriches the repertoire of useful tools available to science. In May 2019, researchers, in a milestone effort, reported the creation of a new synthetic (possibly artificial) form of viable life, a variant of the bacteria Escherichia coli, by reducing the natural number of 64 codons in the bacterial genome to 61 codons (eliminating two out of the six codons coding for serine and one out of three stop codons) – of which 59 used to encode 20 amino acids.
Sources: en.wikipedia.org
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.
It appears in Russian pharmaceutical listings as a nasal formulation, but it is not an authorised medicine in the United States or the European Union. Outside those markets it is normally encountered as a research chemical rather than a prescription product.
Laboratory and animal work points to melanocortin signalling and changes in neurotrophic factor levels, especially brain-derived neurotrophic factor. The exact receptor targets and the degree to which these findings transfer to humans are still unresolved.
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.