The short version of melanocortin signalling fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2025-12-12. Anything still debated is marked as such rather than presented as settled.
Identity and purity of Semax are established mainly by reversed-phase high-performance liquid chromatography coupled with mass spectrometry. The chromatographic trace gives a purity estimate as a percentage of total peak area, while electrospray or matrix-assisted laser desorption ionization confirms the molecular mass against the calculated value. Amino acid analysis and sequence-specific fragmentation provide further confirmation when a supplier's chain of custody is unclear. Vendors frequently quote a purity figure without stating the detection wavelength or the integration method, which limits how far one number can be compared with another.
Stability depends heavily on physical state. Lyophilized powder held dry, cold and dark retains its content over long periods, whereas dissolved peptide begins to change within days at room temperature. The most cited degradation route is oxidation of the methionine residue, which converts the peptide to a sulfoxide form that elutes differently on chromatography. Hydrolysis of amide bonds and adsorption onto container walls contribute smaller losses. Buffers that exclude oxygen from the headspace slow the oxidation pathway, but no single condition prevents all change indefinitely.
Practical handling follows from those properties. Bulk material is best divided into single-use portions soon after receipt, because each thaw exposes the whole container to moisture and temperature cycling. Vials should be allowed to reach room temperature before opening to prevent condensation on the powder. Low-binding plasticware reduces loss of dilute solutions, and sterile filtration is used when a preparation must remain free of microbial growth. Records of batch number, reconstitution date and storage history are what allow a later analytical result to be interpreted meaningfully.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Typical purity specification | ≥ 95 % of peak area by HPLC | Some suppliers quote 98 % or higher |
| Identity confirmation | Mass spectrometry (electrospray or MALDI) | Observed mass is compared with the calculated mass |
| Common analytical method | Reversed-phase HPLC on a C18 column | Acetonitrile and water gradients with trifluoroacetic acid |
| Primary degradation route | Oxidation of the methionine residue | Yields a sulfoxide that separates cleanly on chromatography |
| Storage of dissolved material | Aliquoted and frozen at −20 °C or below | Single-use aliquots avoid repeated temperature cycling |
Once dissolved, the peptide is considerably less stable than the solid. Aqueous solutions are usually prepared at neutral to slightly acidic pH, filtered, and divided into single-use aliquots before freezing. Repeated freeze-thaw cycles are a common cause of avoidable loss and are best prevented by never refreezing a thawed aliquot. Adsorption to plastic and glass surfaces can lower the measured concentration of dilute solutions, particularly below roughly 0.1 mg/mL. Buffer choice, salt content, and container material all influence how much peptide remains detectable after storage.
Identity and purity are established with standard peptide methods. Reversed-phase HPLC with ultraviolet detection near 214 nm resolves the parent peak from deletion and truncation byproducts, and reports typically quote a main-peak percentage. Mass spectrometry by electrospray or MALDI-TOF confirms the expected molecular mass, while amino acid analysis or peptide mapping can verify composition when the sequence itself is in question. A certificate of analysis that pairs a chromatogram with a mass spectrum is more informative than a purity figure alone. Counter-ion content and residual solvents are separate specifications and are frequently omitted.
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.
The mechanisms attributed to semax are inferred from animal and cell studies rather than traced to one confirmed target. The most frequently cited pathway involves increased expression of brain-derived neurotrophic factor and nerve growth factor in hippocampal and cortical tissue. Some work points to engagement of melanocortin receptors, particularly MC4, which the parent ACTH fragment can activate. Effects on dopaminergic and serotonergic signalling have also been reported. No single account explains all observed results, and the relative weight of each pathway remains unsettled.
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.
There are more than 200 groups that we've been able to recognize that call themselves a Cherokee nation, tribe, or band," said Mike Miller, spokesman for the Cherokee Nation. "Only three are federally recognized, but the other groups run the gamut of intent. Some are basically heritage groups – people who have family with Cherokee heritage who are interested in the language and culture, and we certainly encourage that," said Miller. "But the problem is when you have groups that call themselves 'nation', or 'band', or 'tribe', because that implies governance. In 2008, the Cherokee Nation passed the Cherokee Nation Truth in Advertising for Native Art. This law states that only citizens of the three federally recognized Cherokee tribes can sell their artwork, books, or other creative works as being "Cherokee."
The dye substance is a mucous secretion from the hypobranchial gland of one of several species of medium-sized predatory sea snails that are found in the eastern Mediterranean Sea, and off the Atlantic coast of Morocco. David Jacoby remarks that "twelve thousand snails of Murex brandaris yield no more than 1.4 grams (22 grains) of pure dye, enough to colour only the trim of a single garment." These are the marine gastropods Bolinus brandaris the spiny dye-murex (originally known as Murex brandaris Linnaeus, 1758), the banded dye-murex Hexaplex trunculus, the rock-shell Stramonita haemastoma, and less commonly a number of other species such as Bolinus cornutus. The dye is an organic compound of bromine (i.e., an organobromine compound), a class of compounds often found in algae and in some other sea life, but much more rarely found in the biology of land animals. This dye is in contrast to the imitation purple that was commonly produced using cheaper materials than the dyes from the sea snail. In nature, the snails use the secretion as part of their predatory behaviour to sedate prey and as an antimicrobial lining on egg masses. The snail also secretes this substance when it is attacked by predators, or physically antagonized by humans (e.g., poked). Therefore, the dye can be collected either by "milking" the snails, which is more labor-intensive but is a renewable resource, or by collecting and destructively crushing the snails. The dye is collected via the snail-harvesting process, involving the extraction of the hypobranchial gland (located under the mollusk's mantle).
Monster Energy is the primary sponsor for Yamaha Motor Racing in MotoGP since 2019 and also sponsors riders such as Valentino Rossi, Franco Morbidelli, and Francesco Bagnaia. The firm has also been the title sponsor of the Catalan motorcycle Grand Prix since 2014, and the British motorcycle Grand Prix since 2021. The brand has been the main sponsor of the Speedway Grand Prix and Speedway World Cup since 2012, and also supports several riders. Monster has sponsored motocross riders such as Jeremy McGrath, Chad Reed, Ryan Villopoto, Nate Adams, Taka Higashino and Ricky Carmichael. The brand sponsors the Kawasaki, and Yamaha motocross factory teams. In 2016, the firm aided the return of factory Yamaha to the United States as the title sponsor of the team, officially named Monster Energy/360fly/Chaparral/Yamaha Factory Racing. During this time, Monster Energy served as a title sponsor for the Star Racing Yamaha team, which also took over the 450 program from Factory Yamaha in 2021. They have gone on to win the 2021 AMA Pro Motocross Championship with Dylan Ferrandis, and the 2022 AMA Supercross and AMA Pro Motocross Championships with Eli Tomac. The brand is also the main sponsor of the Honda and Hero factory teams in the FIM Cross-Country Rallies World Championship and later the World Rally-Raid Championship since 2016 and 2023 respectively.
Sources: en.wikipedia.org
Analyses of NYTS data indicate that the decline observed between 2023 and 2024 was primarily driven by reductions among high school students. The same report noted that disparities persist, with increased in tobacco product use observed in some groups. US federal reporting has also described a longer-term pattern in which e-cigarette use among young people peaked in 2019 and declined substantially by 2024; during this period, regulatory and enforcement actions against unauthorized e-cigarette products were expanded. Data from other countries provide additional comparisons. In Great Britain, a 2024 ASH/YouGov youth survey reported that vaping among 11-17 year olds appears to have stabilized after earlier increases (ever-use 18% in 2024 compared with 20% in 2023). The same survey reported current vaping at 7.2% among 11-17 year olds (including less-than-monthly use). Additionally, UK reporting has described proposals in the Tobacco and Vapes Bill, including restrictions aimed at reducing youth uptake. Following 2024 UK survey results, the Royal College of Pediatrics and Child Health called for measures including restrictions on disposable e-cigarettes, flavors, and advertising to reduce youth uptake. In Canada, there was a trend showing 29% of young people reporting to have used e-cigarettes in 2017, increasing to 37% in 2018. In New Zealand, school survey data indicated that regular and daily vaping had declined by 2024 after peaking in 2021 and the 2024/25 the New Zealand Health Survey reported that daily smoking had reduced to below 5.0% among people aged 15–24.
These are various dosage forms and technologies which include but not limited to nanoparticles, liposomes, microneedles, and hydrogels that can be used to enhance therapeutic efficacy and safety. The same route can accommodate multiple dosage forms; for example, the oral route may involve tablet, capsule, or liquid suspension. While the transdermal route may use a patch, gel, or cream. Drug delivery incorporates both of these concepts while encompassing a broader scope, including the design and engineering of systems that operate within or across these routes. Common routes of administration include oral, parenteral (injected), sublingual, topical, transdermal, nasal, ocular, rectal, and vaginal. However, modern drug delivery continue to expand the possibilities of these routes through novel and hybrid approaches. Since the approval of the first controlled-release formulation in the 1950s, research into new delivery systems has been progressing, as opposed to new drug development which has been declining. Several factors may be contributing to this shift in focus. One of the driving factors is the high cost of developing new drugs. A 2013 review found the cost of developing a delivery system was only 10% of the cost of developing a new pharmaceutical. A more recent study found the median cost of bringing a new drug to market was $985 million in 2020, but did not look at the cost of developing drug delivery systems.
The number of diseases screened for is set by each jurisdiction, and can vary greatly. Most NBS tests are done by measuring metabolites or enzyme activity in whole blood samples collected on filter paper. Bedside tests for hearing loss using automated auditory brainstem response or otoacoustic emissions and congenital heart defects using pulse oximetry are included in some NBS programs. Infants who screen positive undergo further testing to determine if they are truly affected with a disease or if the test result was a false positive. Follow-up testing is typically coordinated between geneticists and the infant's pediatrician or primary care physician.
In the 20-naughts, Gavi had intense internal debate about its role in vaccinations and in health systems strengthening (HSS). This was part of a broader discussion in healthcare about "vertical" approaches (often targeting specific diseases or behaviours) and "horizontal" ones, targeting broad programs such as primary care. At Gavi, some argued that vaccination could not be effectively carried out and sustained without strengthening healthcare, citing experiences in Gavi's vaccination programmes, where availability of staff, training, transport, and funds had hindered vaccination and reporting of vaccination coverage and stocks. There were also worries that Gavi was undermining and paralyzing health care systems. Others argued that HSS was a distraction from Gavi's single-minded focus on vaccines, and HSS was a nebulous concept that could not be defined and quantified. Major donors Norway and Britain supported HSS; USAID and the Bill & Melinda Gates Foundation (and Bill Gates personally) opposed it. The majority of vaccine experts tended to favour technological rather than HSS-based approaches. Pharmaceutical industry representatives were supportive of HSS, possibly because they saw it as key to sustainable markets for their products. In 2005, a narrow vote brought Gavi to endorse an HSS goal. Up to a quarter of Gavi's funding was dedicated to "strengthening the capacity of integrated health systems to deliver immunisation", in practice it has been around 10%. After 2010, this funding went through a joint-venture Health Systems Funding Platform.
Sources: en.wikipedia.org
Perfectionism identifies well-being with excellence by fulfilling human nature. It holds that one needs to exercise and master key human abilities, such as rationality, knowledge, health, and dignity, to live well. As an objectivist perspective, perfectionism asserts that the value of these goods does not depend on what a person thinks about them. Eudaimonism is a closely related view, asserting that someone has high well-being or flourishes in life by actualizing their inborn potential. This view emphasizes that well-being is not a passive state but an active process. It manifests in an engaged lifestyle where individuals exercise virtues and rely on practical rationality to guide their decision-making. Value fulfillment theories see the satisfaction of evaluative attitudes as the basis of well-being. They are similar to desire theories, which focus on desire satisfaction. However, value fulfillment theories adopt a broader perspective that considers diverse evaluative attitudes in addition to desires, such as beliefs, feelings, and judgments about what is good. Most theories assume that the definition of well-being applies equally to everyone. Variabilism rejects this assumption and argues that different conceptions of well-being apply to different individuals. One form of variabilism asserts that the nature of well-being in children differs from that of adults.
==== Tana Toraja ==== A TED Talk by Kelli Swazey discusses how Tana Toraja, a Sulawesi province in Eastern Indonesia, experiences death as a process, rather than an event. The culture of Tana Toraja views funerals as the most important event in a person's life. Because of this importance placed on death, Tana Toraja landscape is covered in the rituals and events transpired after death. The hierarchy of an individual's life is based on the sacrifices of animals made after their death. Funerals of the Tana Toraja people typically last days to even weeks. Death is seen as a transformation, rather than a private loss. A Torajan is not considered 'dead' until their family members are able to collect the resources necessary to hold a funeral that expresses the status of the deceased. Until these funerals are upheld the deceased are held in Tongkonan, built to house corpses that are not considered 'dead'. The deceased can be held in Tongkonan for years, waiting for their families to collect the necessary resources to hold a funeral. The Tongkonan represents both the identity of the family and the process of birth and death. The process of birth and death is shown by having the houses that individuals are born in be the same structure as the Tongkonan, houses that individuals die in. Until the funeral, the deceased being housed in the Tongkonan are symbolically treated as members of the family, still being cared for by family members.
=== Pharmacodynamics === Dutasteride belongs to a class of drugs called 5α-reductase inhibitors, which block the action of the 5α-reductase enzymes that convert testosterone into DHT. It inhibits all three forms of 5α-reductase, and can decrease DHT levels in the blood by up to 98%. Specifically it is a competitive, mechanism-based (irreversible) inhibitor of all three isoforms of 5α-reductase, types I, II, and III (IC50Tooltip Half-maximal inhibitory concentration values are 3.9 nM for type I and 1.8 nM for type II). This is in contrast to finasteride, which is similarly an irreversible inhibitor of 5α-reductase but only inhibits the type II and III isoenzymes. As a result of this difference, dutasteride is able to achieve a reduction in circulating DHT levels of up to 98%, whereas finasteride is able to achieve a reduction of only 65 to 70%. In spite of the differential reduction in circulating DHT levels, the two drugs decrease levels of DHT to a similar extent of approximately 85 to 90% in the prostate gland, where the type II isoform predominates. Since 5α-reductases degrade testosterone to DHT, the inhibition of these enzymes could theoretically cause an increase in testosterone. A 2018 review found that initiation of 5α-reductase inhibitors did not result in a consistent increase in testosterone levels. Among the studies analyzed, there was no statistically significant change in testosterone levels from 5α-reductase inhibitors overall, though men with lower baseline testosterone levels did show an increase.
Sources: en.wikipedia.org
Suppliers normally quote a percentage of total chromatographic peak area, most often from reversed-phase HPLC. That figure says nothing about what the remaining percentage contains, and it depends on the detection wavelength used. A mass spectrometry result is a separate and stronger check on identity.
The methionine residue at the start of the chain is vulnerable to oxidation, producing a sulfoxide variant. Amide bonds can also hydrolyze, though more slowly under neutral conditions. Cold storage, oxygen exclusion and minimization of freeze-thaw cycles slow both processes but do not stop them.
A purity number on a certificate does not establish that a powder is the same product as a registered nasal medicine. Counter-ion content, residual solvents and peptide-related impurities may differ between the two. Independent verification is the only way to narrow that gap.
It originated at the Institute of Molecular Genetics in Moscow during the 1980s. The work was carried out by a Russian research group that specialized in peptide neuropharmacology.