This is a working overview of heptapeptide, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2026-08-01. Anything still debated is marked as such rather than presented as settled.
Scientific literature on semax is unevenly distributed. A substantial share of published work originates from a small number of laboratories in Russia, while independent replication elsewhere is limited. Human data consist mostly of small trials with short follow-up, and several reported outcomes rely on subjective rating scales. Questions about how much intact peptide reaches the central nervous system after nasal administration, and how long it persists there, are still unresolved. The compound is best described as an active research subject rather than a settled pharmacological agent.
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.
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.
Semax is a synthetic heptapeptide whose sequence is Met-Glu-His-Phe-Pro-Gly-Pro. The first four residues correspond to the ACTH(4-10) fragment, while the terminal Pro-Gly-Pro extension was added to improve metabolic stability. Its molecular formula is C37H51N9O10S and its monoisotopic mass is approximately 813.9 Da. The compound is classified as a peptide research chemical and as a registered pharmaceutical product in Russia, but it does not hold marketing approval in the European Union or the United States. Naming conventions vary across supplier catalogs.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Calculated for the free peptide |
| Molar mass | 813.9 g/mol | Anhydrous free base |
| Peptide class | Synthetic heptapeptide | ACTH(4-10) analogue |
| Parent fragment | ACTH(4-10) | Adrenocorticotropic hormone segment |
| Developmental origin | Institute of Molecular Genetics, Moscow | Work began in the 1980s |
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.
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.
Though these events served as inspiration for the field, the actual breakthrough in practical approaches to synthesize artificial molecular machines (AMMs) took place in 1991 with the invention of a "molecular shuttle" by Sir Fraser Stoddart. Building upon the assembly of mechanically linked molecules such as catenanes and rotaxanes as developed by Jean-Pierre Sauvage in the early 1980s, this shuttle features a rotaxane with a ring that can move across an "axle" between two ends or possible binding sites (hydroquinone units). This design realized the well-defined motion of a molecular unit across the length of the molecule for the first time. In 1994, an improved design allowed control over the motion of the ring by pH variation or electrochemical methods, making it the first example of an AMM. Here the two binding sites are a benzidine and a biphenol unit; the cationic ring typically prefers staying over the benzidine ring, but moves over to the biphenol group when the benzidine gets protonated at low pH or if it gets electrochemically oxidized. In 1998, a study could capture the rotary motion of a decacyclene molecule on a copper-base metallic surface using a scanning tunneling microscope. Over the following decade, a broad variety of AMMs responding to various stimuli were invented for different applications. In 2016, the Nobel Prize in Chemistry was awarded to Sauvage, Stoddart, and Bernard L. Feringa for the design and synthesis of molecular machines.
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.
==== Lungs ==== Inhaled acetylcysteine is also used post-operatively, as a diagnostic aid, and in tracheotomy care. It may be considered ineffective in cystic fibrosis. A 2013 Cochrane review in cystic fibrosis found no evidence of benefit. Acetylcysteine is used in the treatment of obstructive lung disease as an adjuvant treatment.
The war on cartels, also known as Operation Southern Spear, is a United States military and surveillance campaign launched in 2025 by the administration of US president Donald Trump with the declared aims of "detecting, disrupting, and degrading transnational criminal and illicit maritime networks". Some analysts say the operation is a hybridization of the war on terror and the war on drugs. Others have said that removal of Nicolás Maduro from power in Venezuela was an objective of the operation. In mid-August 2025, the US began deploying military forces to the Caribbean Sea, amid heightened tensions between the US and Venezuela during the crisis in Venezuela and as the Trump administration sought to slow the flow of illicit drugs. In September, the U.S. military began conducting airstrikes on vessels the Trump administration alleged were controlled by narco-terrorists. By late November, with the Cartel of the Suns designated by the US as a Foreign Terrorist Organization and a Specially Designated Global Terrorist organization, a new phase of operations began. In December, the Trump administration declared the Maduro government a Foreign Terrorist Organization, and began boarding and seizing sanctioned crude tankers. In late December, the US made its first strike on a land target within Venezuela. On 3 January 2026, the US bombed targets in Caracas and other locations, and captured Maduro and flew him out of the country.
where ± refers to a positive or negative particle, Ip is the incident ion current, f±i is the fraction of particles sputtered as ions, Si is the sputtering yield of both ions and neutrals, Ci is the concentration of the ith element (corrected for isotopic abundance) in the sputtered volume, ηi is the collection efficiency of the SIMS instrument, Ip = d2j/4, d is the diameter of a Gaussian-shaped beam, and j is the current density.
Sources: en.wikipedia.org
small/non-small cell lung cancer oesophageal cancer uterine cervical cancer urothelial cancer testicular cancer ovarian cancer prostate cancer head and neck cancer Nedaplatin is most often compared to other platinum-based drugs, most notably cisplatin. Many randomized controlled trials have been performed to compare nedaplatin and cisplatin, with uncertain results. One meta-analysis of 14 trials indicated no difference in efficacy in terms of median overall survival. Another meta-analysis of 17 trials looking specifically at concurrent chemoradiotherapy treatment for cervical cancer also found no difference in 3 year all-cause mortality, but did favour nedaplatin for 1 year all-cause mortality.
Didymin (also known as isosakuranetin 7-O-rutinoside or neoponcirin) is an O-methylated flavanone glycoside occurring naturally in citrus fruits, consisting of the flavanone isosakuranetin linked to the disaccharide rutinose.
=== Repression and counter-coups === It has been argued that failed coups might motivate a regime to reform and reduce repression. Such reforms are not obvious in the data, as of 2017. Coups that fail, or merely shuffle the leadership without changing the system, generally do not change the amount of repression (measured in government-sanctioned and pro-government killings). Research from 2016 suggests that increased repression and violence typically follow both successful and unsuccessful coup attempts. According to a 2019 study, coup attempts lead to a reduction in physical integrity rights. Coups that lead to democratization unsurprisingly reduce repression, and coups that bring in a new autocratic regime increase it. Post-Cold-War, post-coup autocracies seem to have become more repressive and post-coup democracies less repressive; the gap between them is therefore larger than it was during the Cold War. Averaging across democratic and non-democratic outcomes, most coups seem to tend to increase state repression, even coups against autocrats who were already quite repressive. The time interval in which violence is measured matters. The months after a bloodless coup can be bloody. The small sample size and high variability means that this conclusion again does not reach statistical significance, and a firm conclusion cannot be drawn. According to Naunihal Singh, author of Seizing Power: The Strategic Logic of Military Coups (2014), it is "fairly rare" for the incumbent government to violently purge the army after a failed coup.
==== Muscle ==== Glycogen storage diseases that involve skeletal muscle typically have exercise-induced (dynamic) symptoms, such as premature muscle fatigue, rather than fixed weakness (static) symptoms. Differential diagnoses for glycogen storage diseases that involve fixed muscle weakness, particularly of the proximal muscles, would be an inflammatory myopathy or a limb-girdle muscular dystrophy. For those with exercise intolerance and/or proximal muscle weakness, the endocrinopathies should be considered. The timing of the symptoms of exercise intolerance, such as muscle fatigue and cramping, is important in order to help distinguish it from other metabolic myopathies such as fatty acid metabolism disorders. Problems originating within the circulatory system, rather than the muscle itself, can produce exercise-induced muscle fatigue, pain and cramping that alleviates with rest, resulting from inadequate blood flow (ischemia) to the muscles. Ischemia that often produces symptoms in the leg muscles includes intermittent claudication, popliteal artery entrapment syndrome, and chronic venous insufficiency. Diseases disrupting the neuromuscular junction can cause abnormal muscle fatigue, such as myasthenia gravis, an autoimmune disease. Similar, are Lambert–Eaton myasthenic syndrome (autoimmune) and the congenital myasthenic syndromes (genetic). Diseases can disrupt glycogen metabolism secondary to the primary disease.
Sources: en.wikipedia.org
Semax is based on the ACTH(4-10) fragment, a seven-amino-acid segment of adrenocorticotropic hormone. The synthetic peptide retains the core sequence while removing regions associated with endocrine activity. This modification is intended to isolate effects on the nervous system.
It is registered for clinical use in Russia and a few other countries, typically as a nasal drop formulation. It does not hold approval from the United States Food and Drug Administration or the European Medicines Agency. Outside those markets it is generally handled as a research chemical.
The compound was developed in Moscow and the earliest studies were conducted there, so the primary literature is largely in Russian-language journals. Translation and indexing have been incomplete, which limits access for outside researchers. Independent groups have since published some work, but the total volume remains modest.
It is a synthetic peptide of seven amino acids. Its backbone corresponds to a fragment of adrenocorticotropic hormone extended at the carboxyl end. The material is distributed as a lyophilized solid for laboratory use.