A practical reference on intranasal route: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2025-10-22 and is reviewed periodically as new material appears.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Its design combines the ACTH(4-7) core fragment with a C-terminal Pro-Gly-Pro extension, a modification intended to improve stability and prolong activity. The molecule is hydrophilic, carries no lipid chains or glycosylation, and has a theoretical mass just over 810 daltons in its free form. All seven residues are proteinogenic amino acids, so no non-natural building blocks appear in the backbone. A free N-terminal methionine and C-terminal proline define the unmodified parent peptide.
The compound was developed during the 1980s at the Institute of Molecular Genetics in Moscow as part of research on fragments of adrenocorticotropic hormone. Early work examined short ACTH-derived sequences that retained neurotrophic effects while lacking the endocrine activity of the full hormone. Semax entered clinical use in Russia during the 1990s, where it received registration for several neurological indications. Outside that region it remained primarily a laboratory research material rather than an approved therapeutic. English-language literature on it grew more slowly and frequently cited the original Russian studies.
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.
Semax is a synthetic seven-amino-acid peptide whose sequence extends the ACTH(4-10) fragment with a C-terminal proline-glycine-proline tripeptide. The commonly cited sequence is Met-Glu-His-Phe-Pro-Gly-Pro, giving a molecular formula near C37H51N9O10S and a molecular weight close to 813.9 g/mol. It belongs to the broader class of synthetic ACTH fragments studied for central nervous system effects rather than for adrenal steroid stimulation. In practice the material appears as a lyophilized white powder for laboratory work or as a dilute saline solution in clinical settings.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide | ACTH(4-7) analogue |
| Sequence | Met-Glu-His-Phe-Pro-Gly-Pro | Free N terminus, unmodified side chains |
| Molecular weight | 813.9 Da | Free base; salt forms differ |
| Appearance | White to off-white powder | Lyophilised solid |
| Solubility | Freely soluble in water | Hydrophilic; polar solvents preferred |
研究兴趣主要集中在神经营养因子相关的路径上，包括脑源性神经营养因子与神经生长因子的表达变化。部分实验报告称在特定条件下观察到这些因子的水平上升，但具体信号通路和剂量依赖关系仍未完全厘清。多数公开数据来自细胞模型和动物实验，人体对照研究数量有限。因此，该化合物的作用机制在文献中属于活跃讨论，而非已经确立的定论。
Semax 是一种人工合成的七肽，氨基酸序列为 Met-Glu-His-Phe-Pro-Gly-Pro，单字母缩写记作 MEHFPGP。它被归类为促肾上腺皮质激素片段 ACTH(4-10) 的结构类似物，但并不天然存在于生物体内。母体片段 ACTH(4-10) 的序列为 Met-Glu-His-Phe-Arg-Trp-Gly，Semax 替换了中间两个残基，并在羧基端延长了 Pro-Gly-Pro 三肽。这种延长被普遍认为能提升分子对肽酶的耐受性。
该化合物于二十世纪八十年代在俄罗斯被开发，相关工作由俄罗斯科学院分子遗传学研究所的研究团队主导。开发目标并非复制 ACTH 的完整激素活性，而是寻找保留其神经作用方向、同时去除促肾上腺皮质激素释放效应的短肽片段。研究记录显示，这一方向促成了多个相关短肽的合成与筛选，而 Semax 是其中被研究最广泛的一个。当地文献常以 Семакс 这一名称指代它。
The simplest way to do this is to remove the gene and see what phenotype develops compared to the wild type form. Any differences are possibly the result of the missing gene. Unlike mutagenisis, genetic engineering allows targeted removal without disrupting other genes in the organism. Some genes are only expressed in certain tissues, so reporter genes, like GUS, can be attached to the gene of interest allowing visualization of the location. Other ways to test a gene is to alter it slightly and then return it to the plant and see if it still has the same effect on phenotype. Other strategies include attaching the gene to a strong promoter and see what happens when it is overexpressed, forcing a gene to be expressed in a different location or at different developmental stages.
MD simulation of the full satellite tobacco mosaic virus (STMV) (2006, Size: 1 million atoms, Simulation time: 50 ns, program: NAMD) This virus is a small, icosahedral plant virus that worsens the symptoms of infection by Tobacco Mosaic Virus (TMV). Molecular dynamics simulations were used to probe the mechanisms of viral assembly. The entire STMV particle consists of 60 identical copies of one protein that make up the viral capsid (coating), and a 1063 nucleotide single stranded RNA genome. One key finding is that the capsid is very unstable when there is no RNA inside. The simulation would take one 2006 desktop computer around 35 years to complete. It was thus done in many processors in parallel with continuous communication between them. Folding simulations of the Villin Headpiece in all-atom detail (2006, Size: 20,000 atoms; Simulation time: 500 μs= 500,000 ns, Program: Folding@home) This simulation was run in 200,000 CPU's of participating personal computers around the world. These computers had the Folding@home program installed, a large-scale distributed computing effort coordinated by Vijay Pande at Stanford University. The kinetic properties of the Villin Headpiece protein were probed by using many independent, short trajectories run by CPU's without continuous real-time communication. One method employed was the Pfold value analysis, which measures the probability of folding before unfolding of a specific starting conformation. Pfold gives information about transition state structures and an ordering of conformations along the folding pathway.
=== Ga–Gl === Johan Gadolin (1760–1852), Finnish chemist who discvered yttrium Joseph Louis Gay-Lussac (1778–1850), French chemist and physicist who discovered the Gay-Lussac law, known for discovering that water is made of two parts hydrogen and one part oxygen by volume Charles Frédéric Gerhardt (1816–1856), French chemist known for reforming the notation for chemical formulas, and for synthesizing acetylsalicylic acid (aspirin) Jnan Chandra Ghosh (1894–1959), Indian chemist known for research on strong electrolytes and the dissociation--ionization theory William Giauque (1895–1982), 1949 Nobel Prize in Chemistry for studies of the properties of matter at temperatures close to absolute zero Josiah Willard Gibbs (1839–1903), American chemist and physicist whose work on thermodynamics helped to transform physical chemistry into a rigorous deductive science Walter Gilbert (born 1932), 1980 Nobel Prize in Chemistry for a method of sequencing nucleic acids Cornelia Gillyard (born 1941), American organic chemist known for work with chemicals in the environment Henry Gilman (1893–1986), American chemist who developed organometallic chemistry, and discovered the Gilman reagent Judith Giordan (Thesis 1980), American chemist who worked on unsaturated hydrocarbons and became President-Elect of the American Chemical Society Johann Rudolf Glauber (1604–1670), Dutch-German alchemist and chemist who discovered sodium sulfate and wrote many books Lawrence E. Glendenin (1918–2008), American chemist, co-discovered the element promethium
Placebo-adjusted lean body mass was increased by 4.8% at 0.5 mg/day, 7.2% at 1 mg/day, and 9.1% at 2 mg/day after 12 weeks. As of 2023, LGD-4033 has been less studied than other SARMs like enobosarm, with only three small phase 1 clinical trials and one phase 2 trial, or a total of four clinical studies, having been conducted and reported.
Sources: en.wikipedia.org
The gameplay involves capturing or defending Hybrid NPCs across four maps, incorporating mechanics inspired by Counter-Strike and Vampire Slayer. Vampire Slayer – is a teamplay mod where two sides: vampires and slayers, battle it out in a variety of atmospheric settings. Planet Half-Life called the original release "A great mod". They also reviewed Chapter IV and wrote: "The new maps fit perfectly with the atmosphere built up from the previous releases." PC Zone gave version 1.1 a rating of three out of five, Chapter III a rating of 69%, and Chapter V a rating of 91%. War in Europe – A World War II-themed mod released in 1999 that includes deathmatch, team deathmatch, and capture the flag. The player earns "promotions" by fragging, which allows purchasing of additional weapons. If the player takes a hit, they will start to bleed, which can be treated with a medkit. PC Gameplay reviewed the game in 2001 and gave a rating of six out of ten, calling it worse than Day of Defeat. Wasteland Half-Life – A post-apocalyptic-themed mod with modes for deathmatch, team deathmatch, and objective capture. PC Zone gave it a score of four out of five and said it's not as popular as it deserves to be. .NetGamer said that despite the familiar gameplay, the mod has a top-notch technical execution. They also praised the maps and the character models. Later, an updated version of the mod was released, titled The Wastes. PC Zone gave it a score 69 out of 100 and called it a worthwhile update.
In postmenopausal women, circulating levels of estradiol are below 15 pg/mL. During normal human pregnancy, estrogen production increases progressively and extremely high estrogen levels are attained. Estradiol levels range from 1,000 to 40,000 pg/mL across pregnancy, are on average 25,000 pg/mL at term, and reach levels as high as 75,000 pg/mL in some women.
=== 1986 analysis === Roy Mackal, a biochemist at the University of Chicago and a founding member of the International Society of Cryptozoology (as was F. G. Wood), decided to test the samples himself. In an issue of Cryptozoology in 1986, he wrote, "Gennaro carried out comparative histological examination of the tissue, and concluded that it most resembled contemporary octopus tissue. While these results were highly suggestive, further biochemical work was required for an unambiguous identification of the tissue." Mackal tested samples of the St. Augustine carcass for different amino acids and compared the results with the known amino acid composition of the tissues of a spotted dolphin, a beluga, a giant squid, and two species of octopus.
The first sizeable batch of Boer prisoners taken by the British consisted of those captured at the Battle of Elandslaagte on 21 October 1899. Initially, these POWs were held on troopships in Simons Bay until POW camps in Cape Town and Simonstown were completed. In total, six prisoner of war camps would be set up in South Africa. As numbers grew, the British decided they did not want them kept locally. The capture of 4000 POWs in February 1900 was a key event, which made the British realise they could not accommodate all POWs in South Africa. The British feared they could be freed by sympathetic locals. Moreover, they already had trouble supplying their troops and did not want the added burden of sending supplies for the POWs. Britain therefore sent many POWs overseas. Around 31 prisoner of war camps were consequently set up in British colonies overseas during the war. The first overseas (off African mainland) camps were opened in Saint Helena, which ultimately received about 5,000 POWs. About 5,000 POWs were sent to Ceylon. Other POWs were sent to Bermuda and India.
== Myths == A common myth among radar and microwave communication workers is that the exposure of the genital area to microwaves renders a man sterile for about a day. The power density necessary for this effect is however sufficient to also cause permanent damage.
Sources: en.wikipedia.org
== Mechanical stress and activity indicators == Examining the effects that activities has upon the skeleton allows the archaeologist to examine who was doing what kinds of labor, and how activities were structured within society. Labor within the household may be divided according to gender and age, or be based on other social structures. Human remains can allow archaeologists to uncover these patterns. Living bones are subject to Wolff's law, which states that bones are physically affected and remodeled by physical activity or inactivity. Increases in mechanical stress tend to produce thicker and stronger bones. Disruptions in homeostasis caused by nutritional deficiency or disease or profound inactivity/disuse/disability can lead to bone loss. While the acquisition of bipedal locomotion and body mass appear to determine the size and shape of children's bones, activity during the adolescent growth period seems to exert a greater influence on the size and shape of adult bones than exercise later in life. Muscle or ligament attachment sites on bones (entheses) are also considered to be impacted by habitual biomechanical loading, leading to the occurrence of various entheseal changes. These changes are routinely used in the field to study activity-patterns.
=== As the OAM (1991–1998) === Joseph J. Jacobs was appointed the first director of the OAM in 1992. Jacobs' support for rigorous scientific methodology caused friction with Democrat U.S. Senator Tom Harkin and other OAM patrons. Harkin believed his allergies had been cured by bee pollen pills and expressed frustration with the "unbendable rules" of randomized clinical trials, saying, "it is not necessary for the scientific community to understand the process before the American public can benefit from these therapies." Harkin's office reportedly pressured the OAM to fund studies of favored theories, including the use of bee pollen and antineoplastons as treatments. OAM board member Barrie Cassileth publicly criticized the office as a purveyor of nonsense and described it as a "place where opinions are counted as equal to data". After Harkin appeared on television in 1994 with cancer patients who blamed Jacobs for blocking their access to antineoplastons, Jacobs resigned from the OAM in frustration. In an interview with Science, Jacobs criticized Harkin and other politicians for pressuring his office, promoting certain therapies, and, he says, attempting an end-run around objective science." Harkin drew support from Iowa Democrat Representative Berkley Bedell, who believed that cow colostrum had cured his Lyme disease. The OAM's budget grew in the 1990s. The office drew increasing criticism for its perceived lack of rigorous scientific study of alternative approaches favoring uncritical boosterism.
A particular kind of metastable isomer is the fission isomer or shape isomer. Most actinide nuclei in their ground states are not spherical, but rather prolate spheroidal, with an axis of symmetry longer than the other axes, similar to an American football or rugby ball. This geometry can result in quantum-mechanical states where the distribution of protons and neutrons is so much further from spherical geometry that de-excitation to the nuclear ground state is strongly hindered. In general, these states either return to the ground state, or undergo spontaneous fission, with half-lives of the order of nanoseconds or microseconds, meaning it is metastable. Fission isomers may be specified with a postscript or superscript "f" rather than "m", so that a fission isomer, e.g. of plutonium-240, can be denoted as plutonium-240f or 240f94Pu.
== See also == Carcinoid syndrome Don Meyer, head coach emeritus of the Northern State University men's basketball team. Meyer was found to have carcinoid cancer following an automobile accident in September 2009. Derrick Bell, professor and legal scholar, died of carcinoid cancer on October 5, 2011.
The death of Yazid in 683 led to a major leadership crisis in the caliphate, and "the power of his house seemed to collapse everywhere", in the words of Orientalist Julius Wellhausen. Ubayd Allah initially neglected to support Yazid's son and designated successor, Mu'awiya II and secured oaths of allegiance to himself from the Basran Arab nobility. In a speech addressed to them, he emphasized his connection to Basra and promised to maintain the wealth of the city's inhabitants. Nonetheless, the Basrans turned against him, forcing him to abandon his palace. He was replaced by Abd Allah ibn al-Harith, a member of the Banu Hashim. Ubayd Allah took refuge with the Azdi chieftain Mas'ud ibn Amr in late 683 or early 684. He plotted to restore his governorship by encouraging Mas'ud to form an alliance of the Yamani and Rabi'a tribes against his opponents from the Banu Tamim and Ibn al-Harith. Mas'ud took to the pulpit of Basra's mosque to stir up the revolt, but Tamimi tribesmen under Ibn al-Harith and their asawira allies under Mah-Afridhun, stormed the building and killed Mas'ud. After Mas'ud's death, Ubayd Allah fled the city practically alone in March 684, taking the Syrian desert route to Hawran or Palmyra. In his rush to escape, he left his wife and family behind. When Ubayd Allah arrived in Syria, he found it in political disarray; Caliph Mu'awiya II had died weeks into his rule and a power vacuum ensued with many Syrian noblemen, particularly from the Qaysi tribes, switching allegiance to the rival, Mecca-based caliphate of Abd Allah ibn al-Zubayr.
Sources: en.wikipedia.org
It is a synthetic seven-amino-acid peptide built from the ACTH(4-7) sequence plus a Pro-Gly-Pro tail. It belongs to the family of short ACTH fragments studied for nervous-system effects. Its backbone contains only standard amino acids.
It contains the 4-7 fragment of adrenocorticotropic hormone extended at the C terminus. That truncation removes the region associated with steroidogenic activity. The design intent was to keep neurotrophic properties while avoiding full hormonal effects.
No natural source of the intact heptapeptide is known. It is produced by solid-phase peptide synthesis. Some related ACTH fragments arise as hormone processing products, but the Pro-Gly-Pro extension is a designed addition rather than a natural sequence.
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.