The short version of ACTH(4-10) fits in a sentence. The long version — which is the one that helps — is below.
This page was last updated on 2025-09-30 and is reviewed periodically as new material appears.
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.
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.
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 weight | ~813.9 Da (free heptapeptide) | N-acetylated form is about 42 Da heavier |
| Residue count | 7 (heptapeptide) | Four residues from ACTH(4-10), three added |
| Appearance | White to off-white powder | Usually supplied lyophilized |
| Solubility class | Freely soluble in water | Also dissolves in DMSO and polar organic solvents |
| Related parent fragment | ACTH(4-10) | Parent motif is Met-Glu-His-Phe |
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。
各国监管态度分化明显。俄罗斯按处方药管理,部分东欧国家留有使用记录;欧盟与美国未批准其作为药物上市,市面流通品通常标注为研究用化学品。身份差异意味着标示含量、纯度与无菌性缺少统一核查。体育领域还牵涉反兴奋剂名录,跨境携带则受目的地药品法规约束。
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.
Second-harmonic imaging microscopy (SHIM) is based on a nonlinear optical effect known as second-harmonic generation (SHG). SHIM has been established as a viable microscope imaging contrast mechanism for visualization of cell and tissue structure and function. A second-harmonic microscope obtains contrasts from variations in a specimen's ability to generate second-harmonic light from the incident light while a conventional optical microscope obtains its contrast by detecting variations in optical density, path length, or refractive index of the specimen. SHG requires intense laser light passing through a material with a noncentrosymmetric molecular structure, either inherent or induced externally, for example by an electric field. Second-harmonic light emerging from an SHG material is exactly half the wavelength (frequency doubled) of the light entering the material. While two-photon-excited fluorescence (TPEF) is also a two photon process, TPEF loses some energy during the relaxation of the excited state, while SHG is energy conserving. Typically, an inorganic crystal is used to produce SHG light such as lithium niobate (LiNbO3), potassium titanyl phosphate (KTP = KTiOPO4), or lithium triborate (LBO = LiB3O5). Though SHG requires a material to have specific molecular orientation in order for the incident light to be frequency doubled, some biological materials can be highly polarizable, and assemble into fairly ordered, large noncentrosymmetric structures.
On November 10, 2025 on Live with Kelly and Mark, Larter talked about the importance of working with Higher Ground of Sun Valley, Idaho; her father was in the U.S. Army and deployed to Vietnam during the Vietnam War.
== Function == This gene encodes the alpha-1 chain of type II collagen, a fibrillar collagen found in cartilage and the vitreous humor of the eye. Type II collagen, which adds structure and strength to connective tissues, is found primarily in cartilage, the jelly-like substance that fills the eyeball (the vitreous), the inner ear, and the center portion of the discs between the vertebrae in the spine (nucleus pulposus). Three pro-alpha1(II) chains twist together to form a triple-stranded, ropelike procollagen molecule. These procollagen molecules must be processed by enzymes in the cell. Once these molecules are processed, they leave the cell and arrange themselves into long, thin fibrils that cross-link to one another in the spaces around cells. The cross-linkages result in the formation of very strong mature type II collagen fibers.
Alpha decays for europium-153 have not been found yet, and its theoretically calculated half-life is so high (due to low energy of decay) that this process will probably not be observed in the near future. Promethium can also be formed in nature as a product of spontaneous fission of uranium-238. Only trace amounts can be found in naturally occurring ores: a sample of pitchblende has been found to contain promethium at a concentration of four parts per quintillion (4×10−18) by mass. Uranium is thus "responsible" for 560 g of promethium in Earth's crust. Promethium has also been identified in the spectrum of the star HR 465 in Andromeda; it also has been found in HD 101065 (Przybylski's star) and HD 965. Because of the short half-life of promethium isotopes, they should be formed near the surface of those stars.
Selenoinsulin (abbreviated to Se-Ins) is an experimental insulin analogue first described in 2017. It is a modified form of bovine pancreatic insulin in which the interchain disulfide bond between residues A7 and B7 is replaced with a diselenide bond formed by two selenocysteine residues. In laboratory studies, selenoinsulin retained biological activity comparable to that of bovine pancreatic insulin and showed greater resistance to degradation by the insulin-degrading enzyme (IDE).
Sources: en.wikipedia.org
In September 2024, Trump said the audience "went crazy" for him at the presidential debate the preceding week, although the debate had no audience. On October 6, 2024, The New York Times reported that Trump had maintained a far less active campaign schedule in 2024 than in 2016; the report added that Trump had held only 61 rallies through 2024, compared with 283 in all of 2016. In this same report, they analyzed Trump's speeches, writing, "with the passage of time, the 78-year-old former president's speeches have grown darker, harsher, longer, angrier, less focused, more profane and increasingly fixated on the past, according to a review of his public appearances over the years." The paper commented that Trump has lately seemed "confused, forgetful, incoherent or disconnected from reality" but that it does not get covered much because it is so common. It highlighted an average rally length of 82 minutes compared with 45 minutes in 2016, and a 13% increase in the use of all-or-nothing terms such as "always" and "never". It also found 32% more negative words than positive words compared with 21% in 2016, and a 69% increase in swear words. It cited experts who considered this increase in tangential speech and behavioral disinhibition the potential result of advancing age and cognitive decline. As of October 12, 2024, Trump had declined to release health information going back to 2015 when he first started running for president, despite a promise he made in August 2024 to release records from a recent examination.
=== Biocompatibility, biodegradability, and biodistribution === One major concern with any form of drug delivery system, including nanogels, is potential side effects and damage to healthy tissue in addition to causing a negative immune response with the introduction of a foreign substance. This has to be balanced with the need for nanogels to remain within circulation for an adequate period to deliver cargo and produce a therapeutic effect. To combat a significant immune response, degradable nanogels are the typical default since they are considered less toxic compared to non degradable nanogels. The compliance and small size of degradable nanogels also allows them to travel through blood vessels and reach their target area before consumption by immune cells or filtration by the liver and spleen.
=== Reversibility === Minimal intervention, reversibility, and future treatability are core principles of contemporary conservation. Adhesive treatments that have failed or exceeded their lifespan may need to be removed, which may compromise or further damage delicate textiles. Because affixed supports can affect a fabric's drape or hand, and reversibility is not assured, conservators should evaluate alternative methods before proceeding with treatment. Despite these factors, adhesive consolidation is often the only option for severely damaged textiles. As with all types of treatment, conservators need to find a balance between intervention and potential loss of the artifact, a decision that requires a thoughtful weighing of risks and assessment of the post-treatment consequences. Some alternatives to adhesive consolidation include crepeline encapsulation, pressure mounts, and customized non-vertical display systems.
== Evolution == The oldest trace fossils on bones characteristic of Osedax are from a plesiosaur humerus from the Cambridge Greensand, England, likely reworked from late Albian (c. 100 million years old) sediments and a rib and costal plate from a sea turtle found in Cenomanian (100–93 million years ago) aged sediments of the Chalk Group, England. Further material is known from the Campanian and Maastrichtian. Following the extinction of almost all large marine reptiles at the end of the Cretaceous, Osedax likely persisted on the bones of sea turtles, marine birds, and fish.
Sources: en.wikipedia.org
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.
Semax is a synthetic analog of the ACTH(4-10) fragment rather than a copy of the full hormone. Truncation plus the added tail removes the steroidogenic portion of ACTH. That distinction explains why it is studied for nervous-system effects instead of adrenal stimulation.
It is registered as a prescription product in Russia and has been used there clinically, chiefly by the intranasal route. No approval exists in the United States or the European Union. Availability elsewhere typically falls under research-chemical distribution, with varying purity documentation.
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.