A practical reference on 合成七肽: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2026-04-12 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.
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.
The C-terminal Pro-Gly-Pro extension is not incidental. Proline-rich tails are known to resist several common peptidases, and the published literature attributes the longer half-life of Semax, relative to unmodified ACTH fragments, to this feature. The modification also removes the melanocyte-stimulating and corticosteroidogenic activity that characterizes longer ACTH-derived sequences. Because the molecule is small and hydrophilic, it is typically formulated as an aqueous solution for intranasal or parenteral delivery. Acetylation or amidation at the termini appears in closely related research peptides and shifts the mass by a fixed increment.
| 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 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.
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。
==== PET imaging ==== Similar to MRI imaging, metal radionuclides can be loaded into nanogels and crosslinked to obtain PET radiotracers for imaging. Nanogels containing copper isotopes commonly used for PET imaging demonstrated overall stability and accumulation in tumors, which produced a higher signal in comparison to nearby tissue. Other studies have explored similar technologies with redox-responsive nanogels loaded with an isotope of gallium and other trivalent metals for PET imaging. Nanogels composed of dextran have also been developed for imaging tumor-associated macrophages with radionuclides and targeting the bone.
Playground equipment constructed during the Cold War was intended to foster children's curiosity and excitement about the Space Race. It was installed in both Communist and non-Communist countries throughout the Cold War.
The Straw Hats' Jolly Roger became a symbol of Gen Z protests across the world. The flag was first used in protests in Indonesia in October 2023 in Yogyakarta, during protests against the Gaza war. The flag's usage among protester increased during the August 2025 Indonesian protests, also known as the 17+8 movement, consisting of students protesting against the Indonesian House of Representatives allowance hike, and the rising costs of food and education. The usage of the Straw Hats' Jolly Roger gained attention online and spread around the world. Afterwards, other people began to use this flag as well, including the 2025 Philippine anti-corruption protests and many others. The Straw Hats were inspiring since they are "teenagers who fight against an extremely corrupt ruling class" and consistently do this on behalf of the oppressed and marginalized. One participant in the 2025–2026 Philippine anti-corruption protests said, “I don't want my son to grow up in a country full of corrupt officials. I want him to grow up in a country that is peaceful and promotes equality. These characters did not just entertain me throughout my childhood, they taught me values and morals that somewhat made me who I am today. … these fictional characters taught me something that I did not expect will be a factor on how I perceive society as a whole and on what kind of world I would like my son to grow up in.”
Sources: en.wikipedia.org
Some colorless compounds such as proteins can be quantified at an Optical Density of 280 nm due to the presence of aromatic rings such as tryptophan, tyrosine and phenylalanine but if none of these amino acids are present then the absorption cannot be measured at 280 nm.
Minimal change disease is characterised as a cause of nephrotic syndrome without visible changes in the glomerulus on microscopy. Minimal change disease typically presents with edema, an increase in proteins passed from urine and decrease in blood protein levels, and an increase in circulating lipids (i.e., nephrotic syndrome) and is the most common cause of the nephrotic syndrome in children. Although no changes may be visible by light microscopy, changes on electron microscopy within the glomeruli may show a fusion of the foot processes of the podocytes lining the basement membrane of the capillaries of glomerulus. It is typically managed with corticosteroids and does not progress to chronic kidney disease.
== History == Tanning hide into leather involves a process which permanently alters the protein structure of skin, making it more durable and less susceptible to decomposition and coloring. The place where hides are processed is known as a tannery.
Sources: en.wikipedia.org
== General mammalian research == Migliaro Petroni et al. (2026) describe tracks of a small-bodied, fast-moving mammal from the Upper Cretaceous (Maastrichtian) strata of the Yacoraite Formation (Argentina), assigned to the ichnotaxon Brasilichnium cf. saltatorium and extending known stratigraphic distribution of the ichnogenus Brasilichnium. A new, diverse assemblage of teeth of Paleocene (Torrejonian) mammals is reported from the Tullock Member of the Fort Union Formation (Montana, United States) by Hovatter & Wilson Mantilla (2026). Evidence indicating that carbon isotope excursions and probable warming events during the Danian were associated with strong pulses of turnover of mammalian assemblages is reported from the study of the fossil record from the San Juan Basin (New Mexico, United States) and other basins in the Rocky Mountain Region is presented by Secord et al. (2026). Evidence from the study of teeth of Paleocene placentals from the Nanxiong, Qianshan and Chijiang basins (China), indicating that the studied mammals achieved high dental topographic variability during the first 10 million years of the Cenozoic and that the variability of their dental traits paralleled global and regional environmental changes, is presented by Tseng, Li & Ting (2026), who argue that living placental lineages might originate from phenotypically variable and functionally flexible ancestors such as the mammals from the studied assemblages from paleotropical Asia.
On 15 April 2023, the country's paramilitary Rapid Support Forces launched attacks against al-Burhan's government, claiming to capture key government sites. Al-Burhan claimed these sites were still under the control of his forces, and that fighting was ongoing. The clashes continued until at least 21 April with occasional ceasefires. Al-Burhan was pinned down at SAF headquarters in Khartoum until August 2023, when a military operation enabled him to evacuate to Port Sudan, where he has been based since then. The Sudanese military allegedly received support from Ukraine. Ukraine has also allegedly sent troops to fight in Omdurman. Their rival, the Rapid Support Forces, had reportedly received support from Libya and the United Arab Emirates as well as Russia's Wagner Group. The foreign involvement in the regional war could have a devastating effect on Sudan. Al-Burhan survived an assassination attempt while attending a military graduation ceremony in Gebeit, in July 2024. Five people were killed in the drone attack. In August 2025, a military official in Sudan confirmed that al-Burhan's envoy, Al-Sadiq Ismail, visited Israel in a push to speed the process of formal normalization between both countries through the Abraham Accords, which has been delayed due to the war. It was reported that Sudan wanted Israeli support following the capture of Khartoum by the SAF in exchange for Sudan's recognition.
In 2010, Ian Read was named CEO. In February 2011, Pfizer announced the closure of its UK research and development facility (formerly also a manufacturing plant) in Sandwich, Kent, which at the time employed 2,400 people. In March 2011, Pfizer acquired King Pharmaceuticals for $3.6 billion in cash. King produced emergency injectables such as the EpiPen. On September 4, 2012, the FDA approved bosutinib (Bosulif) for chronic myelogenous leukemia (CML), a rare type of leukemia and a blood and bone marrow disease that affects primarily older adults. In November 2012, Pfizer received approval from the Food and Drug Administration for Xeljanz, a tofacitinib, for rheumatoid arthritis and ulcerative colitis. The drug had sales of $1.77 billion in 2018, and in January 2019, it was the top drug in the United States for direct-to-consumer advertising, passing adalimumab (Humira). In 2023, the Institute for Clinical and Economic Review (ICER) identified Xeljanz (tofacitinib) as one of five high-expenditure drugs that experienced significant net price increases without new clinical evidence to justify the hikes. Specifically, Xeljanz's wholesale acquisition cost rose by 6%, leading to an additional $72 million in costs to U.S. payers. On February 1, 2013, Zoetis, the Agriculture Division of Pfizer and later Pfizer Animal Health, became a public company via an initial public offering, raising $2.2 billion. Later in 2013, Pfizer completed the corporate spin-off of its remaining stake in Zoetis.
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.
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.