lyophilized powder 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 2026-07-01. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Seven-residue peptide |
| Molecular mass | 813.9 Da | Monoisotopic value |
| Appearance | White to off-white powder | Lyophilized form |
| Solubility | Freely soluble in water | Also soluble in saline and polar solvents |
| Storage (dry) | -20 °C or lower | Desiccated, protected from light |
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。
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。
Laboratory descriptions of the material are consistent across suppliers. It appears as a white to off-white lyophilized powder that dissolves readily in water and in polar organic solvents such as dimethyl sulfoxide. Aqueous solutions are clear and colorless at low concentrations. Because the peptide contains methionine, oxidation at the sulfur atom is a recognized degradation pathway, and handling notes usually call for protected, desiccated storage. Reported purity for research-grade lots is generally above 95 percent as measured by reversed-phase high-performance liquid chromatography.
The compound is registered in Russia as a pharmaceutical product, most commonly formulated as a nasal solution, and has been used in that setting since the 1990s. Outside that jurisdiction it is generally handled as a research chemical rather than an approved medicine. Regulatory status therefore differs sharply between countries, and material sold internationally may not correspond to the Russian pharmaceutical formulation. Documentation with commercial samples is typically limited to a certificate of analysis covering purity and identity, not clinical status or local legal classification.
=== Sydenham's laudanum === In the 1660s English physician Thomas Sydenham (1624–1689) popularized a proprietary opium tincture that he also named laudanum, although it differed substantially from the laudanum of Paracelsus. In 1676 Sydenham published a seminal work, Medical Observations Concerning the History and Cure of Acute Diseases, in which he promoted his brand of opium tincture, and advocated its use for a range of medical conditions.
U.S. Navy Fleet Admiral Hyman G. Rickover, nicknamed "Father of the Nuclear Navy", was forcibly retired four days after his 82nd birthday. Admiral Rickover's 63 years of active service in the U.S. Navy made him the longest-serving member of the U.S. armed forces. The fifth annual Charity Shield game of Australia's National Soccer League was played, matching the 1981 first-place finisher (Sydney City and the NSL Cup winner, the Brisbane Lions. Sydney City won, 3 to 1. Born: Marta Nieto, Spanish film and television actress known for the 2019 film Madre; in Murcia Jena Lee Nardella, American activist for clean water and ending AIDS in Africa; in Woodland, California Helena Paparizou, Swedish-born Greek singer; in Borås, Västergötland Died: Agnes Sligh Turnbull, 93, American novelist Kuljeet Singh and Jasbir Singha, convicted kidnappers and murderers who had killed two teenagers in India in 1978, were hanged at the Tihar Jail in New Delhi. Captain Cyril Gourley, 89, British Army officer and recipient of the Victoria Cross.
BRINP2-related peptide (BRP) is a synthetic peptide that displays anti-obesity action similar to semaglutide. It does this without significant muscle loss or anxiety and without impacting bowel movement when administered to mice and pigs. BRP primarily stimulates receptors in the hypothalamus and is consistent with GPCR activation leading to stimulation of CREB and Fos activity in neuronal cells. Researchers at Stanford University derived BRP from the BRINP2 protein, corresponding to amino acids 386–397 (THRILRRLFNLC) of BRINP2. This 12-amino acid peptide is flanked by KK and KR recognition sites within the BRINP2 protein, which are cleaved by proprotein convertases to release the peptide. BRP has been detected in human cerebrospinal fluid by mass spectrometry. Additionally, BRP undergoes C-terminal amidation, resulting in the sequence THRILRRLFNLC-NH2. The non-amidated form of the peptide is inactive.
==== Thyroid hormone receptors ==== In chronic liver and renal (kidney) failure, increased THR expression occurs. In contrast, in acute illness such as sepsis and trauma, decreased THR expression occurs.
Sources: en.wikipedia.org
Neurotransmitter receptors and receptor ionophores. Nicotinic, imidazoline I1 and I2, α2-adrenergic, glutamate NMDAr, and serotonin 5-HT2A and 5HT-3 receptors. Ion channels. Including: ATP-sensitive K+ channels, voltage-gated Ca2+ channels, and acid-sensing ion channels (ASICs). Membrane transporters. Agmatine specific-selective uptake sites, organic cation transporters (mostly OCT2 subtype), extraneuronal monoamine transporters (ENT), polyamine transporters, and mitochondrial agmatine specific-selective transport system. Nitric oxide (NO) synthesis modulation. Both differential inhibition and activation of NO synthase (NOS) isoforms is reported. Polyamine metabolism. Agmatine is a precursor for polyamine synthesis, competitive inhibitor of polyamine transport, inducer of spermidine/spermine acetyltransferase (SSAT), and inducer of antizyme. Protein ADP-ribosylation. Inhibition of protein arginine ADP-ribosylation. Matrix metalloproteases (MMPs). Indirect down-regulation of the enzymes MMP 2 and 9. Advanced glycation end product (AGE) formation. Direct blockade of AGEs formation. NADPH oxidase. Activation of the enzyme leading to H2O2 production.
Proteins are often thought of as relatively stable tertiary structures that experience conformational changes after being affected by interactions with other proteins or as a part of enzymatic activity. However, proteins may have varying degrees of stability, and some of the less stable variants are intrinsically disordered proteins. These proteins exist and function in a relatively 'disordered' state lacking a stable tertiary structure. As a result, they are difficult to describe by a single fixed tertiary structure. Conformational ensembles have been devised as a way to provide a more accurate and 'dynamic' representation of the conformational state of intrinsically disordered proteins. Protein ensemble files are a representation of a protein that can be considered to have a flexible structure. Creating these files requires determining which of the various theoretically possible protein conformations actually exist. One approach is to apply computational algorithms to the protein data in order to try to determine the most likely set of conformations for an ensemble file. There are multiple methods for preparing data for the Protein Ensemble Database that fall into two general methodologies – pool and molecular dynamics (MD) approaches (diagrammed in the figure). The pool based approach uses the protein's amino acid sequence to create a massive pool of random conformations. This pool is then subjected to more computational processing that creates a set of theoretical parameters for each conformation based on the structure.
== Change of properties with temperature == All materials change with temperature, but superheated water exhibits greater changes than would be expected from temperature considerations alone. Viscosity and surface tension of water drop and diffusivity increases with increasing temperature.
Other families claimed that their loved ones did not have any problems with anybody and were honest workers. Nevertheless, when the cartel members arrested were interrogated by the authorities, they claimed that those killed in the massacre were not innocent, and formed part of Los Torcidos (another name for the Jalisco New Generation Cartel). When asked if they had tortured them, the cartel members replied that they did not. One of the killers confessed that he had plans of leaving the criminal organization but was threatened with death by his own organization if he decided to do so. Authorities concluded that this massacre was almost a "replica" of what happened two months earlier in Veracruz, and investigators mentioned that this massacre is a response to the killings done by the Matazetas against Los Zetas in the state of Veracruz.
These three receptors have been renamed as FPR1, FPR2, and FPR3 and found to have very different specificities for the formyl oligopeptides and very different functions that include initiating inflammatory responses to N-formyl peptides released not only by bacteria but also a multiplicity of elements released by host tissues; dampening and resolving inflammatory responses; and perhaps contributing to the development of certain neurological cancers and an array of neurological diseases Amyloid-based diseases.
Sources: en.wikipedia.org
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.
The extension was introduced to slow enzymatic breakdown of the peptide in biological systems. Natural ACTH fragments are degraded rapidly by peptidases. Adding the tripeptide was intended to extend the window during which the molecule remains intact.
Most published work consists of animal experiments conducted in a small number of laboratories. Human data are limited in number and size. Whether the observed effects translate into reliable clinical benefit is still unresolved.
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.