nootropic 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 2026-02-21. Where a claim depends on a specific study, the study is described rather than over-claimed.
Development is attributed to researchers at the Institute of Molecular Genetics in Moscow during the early 1980s, building on earlier Soviet work with ACTH fragments. Russian regulatory approval followed for intranasal use, and the compound has remained commercially available there for decades. Most published human data originate from Russian and, later, some Eastern European clinical reports, which are not always accessible in English translation. Outside that region the material is generally handled as a research chemical rather than a licensed medicine.
Regulatory status differs sharply between jurisdictions. In Russia the peptide is registered as a prescription nasal preparation, while agencies such as the United States Food and Drug Administration have not approved it for any indication. Products sold elsewhere are typically labeled for laboratory research only, and such labels shift responsibility for safe handling to the purchaser. Because the same name covers pharmaceutical-grade nasal drops and bulk research powder, identity and purity documentation becomes the main practical concern when comparing sources.
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.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide (ACTH fragment analog) | Not a steroid; does not belong to the melanocortin agonist drugs by marketing category |
| Molecular formula | C37H51N9O10S (commonly cited) | Reported values vary slightly with salt and counter-ion content |
| Appearance | White to off-white lyophilized powder | A single batch may appear as a loose cake or fluffy solid |
| Solubility | Freely soluble in water and aqueous buffer | Stock solutions are usually prepared in sterile water or saline |
| Typical storage | −20 °C or below, desiccated and protected from light | Seal opened vials promptly to limit moisture uptake |
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.
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 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.
=== Medieval to early modern era === In medieval Europe, merchant guilds organized long-distance commerce and also participated in local wholesale trade. These guilds protected members, negotiated privileges, and in some places influenced city government and rules that shaped how goods were distributed and sold. In many regions, food distribution also relied on wholesale markets where trade concentrated in one place. Over time, wholesale markets became important for matching supply with demand and supporting price formation in urban food systems.
=== Distributor's losses and impact === Though Darbar became the highest-grossing Tamil film of 2020, grossing ₹202–250, several distributors claimed that they incurred significant financial losses due to the film’s high acquisition costs and pre-release rights pricing. Trade analysts estimated that distributors collectively suffered losses of around ₹70 crore. It did not perform well in other Indian states, including Andhra Pradesh and Telangana, due to competition from Ala Vaikunthapurramuloo and Sarileru Neekevvaru, and the Hindi version was unsuccessful at the box office due to a lack of promotion. Following unsuccessful discussions with Lyca Productions, a group of distributors attempted to approach Rajinikanth seeking financial relief. Media reports stated that some distributors threatened protests, including hunger strikes, if their concerns were not addressed. Industry commentators later compared the situation to earlier Rajinikanth films such as Baba (2002), Kuselan (2008) and Lingaa (2014). Trade publications attributed the dispute primarily to the film’s high production and acquisition costs. Reports indicated that Rajinikanth and director A. R. Murugadoss received substantial remuneration, contributing to an increased production budget, while the film’s distribution rights were sold at premium rates. Some commentators cited the episode as part of a broader industry debate on the financial risks associated with high-budget star-driven films.
== Bite == It is a common misconception that P. phalangioides is incapable of biting humans due to an inability of their fangs to penetrate the human epidermis. These spiders can bite humans since their fangs are roughly 0.25 mm long, while the thickness of the human epidermis is less, around 0.1 mm thick; however, there are hardly any reports on bites.
The harvesting, processing, and consuming of seafoods are ancient practices with archaeological evidence dating back well into the Paleolithic. Findings in a sea cave at Pinnacle Point in South Africa indicate Homo sapiens (modern humans) harvested marine life as early as 165,000 years ago, while the Neanderthals, an extinct human species contemporary with early Homo sapiens, appear to have been eating seafood at sites along the Mediterranean coast beginning around the same time. Isotopic analysis of the skeletal remains of Tianyuan man, a 40,000-year-old anatomically modern human from eastern Asia, has shown that he regularly consumed freshwater fish. Archaeology features such as shell middens, discarded fish bones, and cave paintings show that sea foods were important for survival and consumed in significant quantities. During this period, most people lived a hunter-gatherer lifestyle and were, of necessity, constantly on the move. However, early examples of permanent settlements (though not necessarily permanently occupied), such as those at Lepenski Vir, were almost always associated with fishing as a major source of food. The ancient river Nile was full of fish; fresh and dried fish were a staple food for much of the population. The Egyptians had implements and methods for fishing and these are illustrated in tomb scenes, drawings, and papyrus documents. Some representations hint at fishing being pursued as a pastime.
During the process of creating new queens, the workers construct special queen cells. The larvae in these cells are fed with copious amounts of royal jelly. This type of feeding in part triggers the development of queen morphology, including the fully developed ovaries needed to lay eggs. Note however that some newer research shows it is not solely the presence of royal jelly that develops the queen but rather the absence of certain other nutrients fed to worker bees. Royal jelly is sometimes used in alternative medicine under the category apitherapy. It is often sold as a dietary supplement for humans, but the European Food Safety Authority concluded in 2011 that evidence does not support the claim that consuming royal jelly offers health benefits to humans. In the United States, the Food and Drug Administration has taken legal action against companies that have marketed royal jelly products using unfounded claims of health benefits.
Sources: en.wikipedia.org
=== Youth === The top three riders in the final results of each World Tour event's young rider classification received points towards the standings. Six points were awarded to first place, four points to second place and two points to third place.
trans-acting Affecting a gene or sequence on a different nucleic acid molecule or strand. A locus or sequence within a particular DNA molecule such as a chromosome is said to be trans-acting if it or its products influence or act upon other sequences located relatively far away or on an entirely different molecule or chromosome. For example, a DNA-binding protein acts "in trans" if it binds to or interacts with a sequence located on any strand or molecule different from the one on which it is encoded. Contrast cis-acting.
The signal change manifests itself in an increase or decrease in the current (electrical) or in a change in the intensity or wavelength of the fluorescence emission (optical). Depending on the type of application, both electrical or optical signal transmission can be advantageous. For sensitive measurement of electronic changes, field-effect transistors (FET) are often used in which the flow of charges within the SWCNTs is measured. The FET structures allow easy on-chip integration and can be parallelized to detect multiple target analytes simultaneously. However, such sensors are more invasive for in vivo applications, as the entire device has to be inserted into the body. Optical detection with semiconducting SWCNTs is based on the radiative recombination of excitons in the near-infrared (NIR) by prior optical (fluorescence) or electrical excitation (electroluminescence). The emission in the NIR enables detection in the biological transparency window, where optical sensor applications benefit from reduced scattering and autofluorescence of biological samples and consequently a high signal-to-noise ratio. Compared to optical sensors in the UV or visible range, the penetration depth in biological tissue is also increased. In addition to the advantage of a contactless readout SWCNTs have excellent photostability, which enables long-term sensor applications. Furthermore, the nanoscale size of SWCNTs allows dense coating of surfaces which enables chemical imaging, e.g. of cellular release processes with high spatial and temporal resolution.
=== Clinical marker === Genome-wide association studies identified ADAMTS7 as a risk locus for coronary artery disease. Studies have been carried on classification of ADAMTS7 binding site, which may serve as the first step toward developing a new therapeutic target for coronary artery disease. Significant associations for coronary artery calcification with SNPs in ADAMTS7 has also been found in Hispanics. Additionally, a multi-locus genetic risk score study based on a combination of 27 loci, including the ADAMTS7 gene, identified individuals at increased risk for both incident and recurrent coronary artery disease events, as well as an enhanced clinical benefit from statin therapy. The study was based on a community cohort study (the Malmo Diet and Cancer study) and four additional randomized controlled trials of primary prevention cohorts (JUPITER and ASCOT) and secondary prevention cohorts (CARE and PROVE IT-TIMI 22).
Sources: en.wikipedia.org
== Pharmacokinetics == Acitretin is a metabolite of etretinate, which was used prior to the introduction of acitretin. Etretinate was discontinued because it had a narrow therapeutic index as well as a long elimination half-life (t1/2 = 120 days), making dosing difficult. In contrast, acitretin's half-life is approximately 2 days. However, because acitretin can be reverse metabolised into etretinate which has an extremely long half-life, women must avoid becoming pregnant for at least three years after discontinuing acitretin. Therefore, acitretin is generally not recommended for women of child-bearing age with a risk of becoming pregnant.
With a triple on May 7, 2001, against Chicago, Bagwell achieved the 700th extra base hit of his career. For the second time in his career, he reached seven RBI in a game — again tying a club record — at Kansas City on July 7. Over four successive games from July 8–13, Bagwell homered and totaled five home runs in that span. In a contest at Enron Field against the St. Louis Cardinals on July 18, he hit for the cycle. He went 4-for-5 with five RBI as the Astros won, 17–11. He was the NL Player of the Month that July after batting .333 with nine home runs, and breaking his own club record with 36 RBI in a month, exceeding the 34 RBI in the previous August. While hitting his 32nd home run on August 19, 2001, against Pittsburgh, Bagwell collected his 100th RBI. It was the sixth consecutive season he reached at least 30 home runs and 100 RBI, making him the eighth player in MLB history to achieve such a streak, and the only Houston player to do so. Five days later, also against Pittsburgh, he scored his 100th run, joining Jimmie Foxx, Lou Gehrig, and Babe Ruth as the only players in MLB history with six consecutive seasons of 30 homers, 100 RBI and 100 runs scored. On September 30 at Chicago, Bagwell walked for his 100th of the season, thus making him the only player in MLB history to register six consecutive seasons of at least 30 home runs, 100 RBI, 100 runs scored, and 100 walks. The Astros won the NL Central division title and faced the Atlanta Braves in the NLDS.
The Daily Telegraph reported in April 2009 that it was manufactured in China, but it has since been made illegal there. In March 2009, Druglink magazine reported it only cost a "couple of hundred pounds" to synthesise a kilogram of mephedrone, the same month, The Daily Telegraph reported manufacturers were making "huge amounts of money" from selling it. In January 2010, Druglink magazine reported dealers in Britain spent £2,500 to ship one kilogram from China, but could sell it for £10 a gram, making a profit of £7,500. A later report, in March 2010, stated the wholesale price of mephedrone was £4000 per kilogram. In March 2011, the International Narcotics Control Board published a report about designer drugs, noting mephedrone was by then being used recreationally in Europe, North America, Southeast Asia, New Zealand and Australia. After the 2022 Russian invasion of Ukraine, existing street drugs in Russia became more expensive, leading an increasing number of Russians to turn to mephedrone. According to reports, DIY mephedrone-making kits are widely available in the country.
Sources: en.wikipedia.org
It is a short synthetic peptide built from seven amino acids: methionine, glutamic acid, histidine, phenylalanine and three prolines. The sequence derives from the 4-10 fragment of adrenocorticotropic hormone with an added proline-glycine-proline tail. No plant or animal extract is involved; the material is produced by solid-phase peptide synthesis.
It was developed in the Soviet Union during the early 1980s by groups at the Institute of Molecular Genetics in Moscow. Russian approval for intranasal use followed, and it has been marketed there since. Western laboratories encountered it mainly through translated literature and, later, through online research-chemical trade.
It holds a Russian registration as a prescription nasal product but has no approval from the European Medicines Agency or the United States Food and Drug Administration. Buyers outside Russia usually receive material sold strictly for laboratory research. That distinction matters because research-grade and pharmaceutical-grade products carry different documentation and testing expectations.
The sequence is Met-Glu-His-Phe-Pro-Gly-Pro, a seven-residue peptide. The first four residues correspond to the ACTH(4-10) fragment, and Pro-Gly-Pro is added at the C-terminus. N-acetylated versions also appear in the literature and differ in mass.