heptapeptide 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.
Updated 2026-07-17. Numbers and descriptions here follow the published literature rather than marketing material.
Development took place during the 1980s at institutes of the Russian Academy of Sciences, where peptide fragments of ACTH were screened for cognitive and neuroprotective effects. The compound received regulatory approval in Russia as a nasal preparation, marketed for conditions such as ischemic stroke, transient ischemic attacks, and optic nerve disorders. Registration in other countries has not followed. Most published clinical reports originate from a small number of Russian research groups, and independent replication outside that setting remains limited. The regulatory status therefore differs sharply between Russia and the rest of the world.
Laboratory work points toward modulation of neurotrophic signaling, particularly expression of brain-derived neurotrophic factor and nerve growth factor in hippocampal tissue. Studies also describe effects on monoamine turnover, inflammatory mediators, and oxidative markers. These observations come mainly from animal models and cultured cells, so the causal chain in humans is not firmly established. Whether the reported molecular changes translate into measurable clinical benefit is an open question. Reviews generally present the mechanism as plausible rather than demonstrated.
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 |
|---|---|---|
| Sequence | Met-Glu-His-Phe-Pro-Gly-Pro | Heptapeptide; ACTH(4-10) analog extended at C-terminus |
| Molecular mass | ~813.9 Da | Free peptide, unmodified |
| Appearance | White to off-white powder | Typical lyophilized solid |
| Solubility | Soluble in water and saline | Also soluble in common aqueous buffers |
| Storage (solid) | -20 °C, desiccated | Protect from moisture and repeated thawing |
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.
Pharmacological accounts link semax to melanocortin signalling and to modulation of neurotrophic factor expression, particularly brain-derived neurotrophic factor and nerve growth factor. Much of this evidence comes from rodent studies using intranasal delivery, a route chosen because it allows peptides to reach the central nervous system with limited systemic exposure. Whether the same mechanisms operate in humans at comparable magnitude remains an open question. The precise receptor or receptors responsible for the reported behavioural and neuroprotective effects have not been conclusively identified.
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.
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.
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。
=== Contestants === 1st - Manny Martinez, Bakery Owner from San Antonio, Texas 2/3/4th - Aaron Davis, Pastry Lead from Surprise, Arizona. 2/3/4th - Joel Gonzalez, Executive Pastry Chef from Scottsdale, Arizona 2/3/4th - Hollie Rivera, Assistant Pastry Chef from Winnipeg, Manitoba 5th - Lillian Chng, Home Bakery Owner from San Diego, California 6th - Thierry Aujard, Executive Pastry Chef from Norristown, Pennsylvania 7th - Megan Aucone, Pastry Chef and Cake Artist from Sayreville, New Jersey 8th - JL Hinojosa, Pastry Chef de Partie from Austin, Texas 9th - Carly Robertson, Bakery Owner from Lehi, Utah 10th - Samantha Santiago Torres, Executive Pastry Chef from Chicago, Illinois
=== Bone marrow suppression === Chloramphenicol may cause bone marrow suppression during treatment; this is a direct toxic effect of the drug on human mitochondria. This effect manifests first as a fall in hemoglobin levels, which occurs quite predictably once a cumulative dose of 20 g has been given. The anaemia is fully reversible once the drug is stopped and does not predict future development of aplastic anaemia. Studies in mice have suggested existing marrow damage may compound any marrow damage resulting from the toxic effects of chloramphenicol.
== SJ == SJ (s) Svalbard and Jan Mayen (ISO 3166 digram) (i) Societas Iesu (Latin: The Society of Jesus, the Jesuit order) (i) Statens Järnvägar (Swedish State Railways) SJA – (i) Staff Judge Advocate (military law) SJC – (i) Supreme Judicial Court of Massachusetts (note: the highest court in the state of Maine is also called the Supreme Judicial Court) SJM – (s) Svalbard and Jan Mayen (ISO 3166 trigram) SJW – (i) Social Justice Warrior
Patient may feel itchy or having hives but the symptoms are usually mild and can be controlled by stopping the transfusion and giving antihistamines. Anaphylactic reactions are rare life-threatening allergic conditions caused by IgA anti-plasma protein antibodies. For patients who have selective immunoglobulin A deficiency, the reaction is presumed to be caused by IgA antibodies in the donor's plasma. The patient may present with symptoms of fever, wheezing, coughing, shortness of breath, and circulatory shock. Urgent treatment with epinephrine is needed. Post-transfusion purpura is an extremely rare complication that occurs after blood product transfusion and is associated with the presence of antibodies in the patient's blood directed against both the donor's and recipient's platelets HPA (human platelet antigen). Recipients who lack this protein develop sensitization to this protein from prior transfusions or previous pregnancies, can develop thrombocytopenia, bleeding into the skin, and can display purplish discolouration of skin which is known as purpura. Intravenous immunoglobulin (IVIG) is treatment of choice. Transfusion-related acute lung injury (TRALI) is a syndrome that is similar to acute respiratory distress syndrome (ARDS), which develops during or within 6 hours of transfusion of a plasma-containing blood product. Fever, hypotension, shortness of breath, and tachycardia often occurs in this type of reaction.
Sources: en.wikipedia.org
Examples of landmark, and frequently controversial judgments, include Van Gend en Loos (holding EU law to created a new legal order, and citizens could sue for treaty rights), Mangold v Helm (establishing equality as a general principle of EU law), and Kadi v Commission (confirming international law had to conform with basic principles of EU law). Until 2016, there was the European Union Civil Service Tribunal, which dealt with EU institutions' staff issues.
Due to their higher levels of androgen exposure during fetal development, the female hyenas are significantly more muscular and aggressive than their male counterparts; social-wise, they are of higher rank than the males, being dominant or dominant and alpha, and the females who have been exposed to higher levels of androgen than average become higher-ranking than their female peers. Subordinate females lick the clitorises of higher-ranked females as a sign of submission and obedience, but females also lick each other's clitorises as a greeting or to strengthen social bonds; in contrast, while all males lick the clitorises of dominant females, the females will not lick the penises of males because males are considered to be of lowest rank. The female spotted hyenas urinate, copulate and give birth through the clitoris since the urethra and vagina exit through the clitoral glans. This trait makes mating more laborious for the male than in other mammals, and also makes attempts to sexually coerce (physically force sexual activity on) females futile. Joan Roughgarden, an ecologist and evolutionary biologist, said that because the hyena's clitoris is higher on the belly than the vagina in most mammals, the male hyena "must slide his rear under the female when mating so that his penis lines up with [her clitoris]". In an action similar to pushing up a shirtsleeve, the "female retracts the [pseudo-penis] on itself, and creates an opening into which the male inserts his own penis". The male must practice this act, which can take a couple of months to successfully perform.
=== Vagus nerve stimulation === Vagus nerve stimulation (VNS) uses an implanted electrode and generator to deliver electrical pulses to the vagus nerve, one of the primary nerves emanating from the brain. It is an approved therapy for treatment-resistant depression in the EU and US and is sometimes used as an adjunct to existing antidepressant treatment. The support for this method comes mainly from open-label trials, which indicate that several months may be required to see a benefit. The only large double-blind trial conducted lasted only 10 weeks and yielded inconclusive results; VNS failed to show superiority over a sham treatment on the primary efficacy outcome, but the results were more favorable for one of the secondary outcomes. The authors concluded "This study did not yield definitive evidence of short-term efficacy for adjunctive VNS in treatment-resistant depression."
=== Bio-distribution studies === In pre-clinical trials, a new drug can be radiolabeled and injected into animals. Such scans are referred to as biodistribution studies. The information regarding drug uptake, retention and elimination over time can be obtained quickly and cost-effectively compare to the older technique of killing and dissecting the animals. Commonly, drug occupancy at a purported site of action can be inferred indirectly by competition studies between unlabeled drug and radiolabeled compounds to bind with specificity to the site. A single radioligand can be used this way to test many potential drug candidates for the same target. A related technique involves scanning with radioligands that compete with an endogenous (naturally occurring) substance at a given receptor to demonstrate that a drug causes the release of the natural substance.
To distribute the compressive forces exerted on the heel during gait, and especially the stance phase when the heel contacts the ground, the sole of the foot is covered by a layer of subcutaneous connective tissue up to 2 cm thick (under the heel). This tissue has a system of pressure chambers that both acts as a shock absorber and stabilises the sole. Each of these chambers contains fibrofatty tissue covered by a layer of tough connective tissue made of collagen fibers. These septa ("walls") are firmly attached both to the plantar aponeurosis above and the sole's skin below. The sole of the foot is one of the most highly vascularized regions of the body surface, and the dense system of blood vessels further stabilize the septa.
Sources: en.wikipedia.org
=== Health care services === The disparity between those benefiting from treatment and those receiving it, known as the "treatment gap", arises from several factors. These include reluctance to seek treatment, healthcare providers' underdiagnosis, and limited availability and accessibility to advanced treatments. Furthermore, establishing clear pathways to services and medical care remains a challenge, complicating access to treatment for individuals with BPD. Despite efforts, many healthcare providers lack the training or resources to address severe BPD effectively, an issue acknowledged by both affected individuals and medical professionals. In the context of psychiatric hospitalizations, individuals with BPD constitute approximately 20% of admissions. While many engage in outpatient treatment consistently over several years, reliance on more restrictive and expensive treatment options, such as inpatient admission, tends to decrease over time. Service experiences vary among individuals with BPD. Assessing suicide risk poses a challenge for clinicians, with patients underestimating the lethality of self-harm behaviors. The suicide risk among people with BPD is significantly higher than that of the general population, characterized by a history of multiple suicide attempts during crises.
== The elements of instrumentation == Instrumentation includes sensing devices to measure process parameters such as pressure, temperature, liquid level, flow, velocity, composition, density, weight; and mechanical and electrical parameters such as vibration, position, power, current and voltage.
== Scientific work and contributions == Richardson's first forays into science were in the field of astronomy. By observing the position of Sputnik – at the time, the only artificial satellite – on two successive nights, she managed to calculate its predicted orbit. She submitted her results to the Westinghouse Science Talent Search, winning third place in 1958. Richardson joined her husband David C. Richardson, then completing his PhD work at MIT, in studying the 3-dimensional structure of the staphylococcal nuclease protein (1SNS) by X-ray crystallography for his doctoral thesis. Staphylococcal nuclease was among the first dozen protein structures solved. Classes in botany and evolution that she had taken while pursuing her degree shaped her thinking about the work she was doing in the chemistry laboratory. During her crystallographic studies, Jane Richardson had come to realize that a general classification scheme can be developed from the recurring structural motifs of the proteins. In the meantime, Jane and David Richardson had moved to Duke University in 1970, where they solved the first crystal structure of superoxide dismutase (2SOD). By 1977 she published her findings on protein relatedness in Nature, with a paper entitled "β-sheet topology and the relatedness of proteins".
== Context == Selection acts on variation in phenotypes, which are often the result of mutations in protein-coding genes. The genetic code is written in DNA sequences as codons, groups of three nucleotides. Each codon represents a single amino acid in a protein chain. However, there are more codons (64) than amino acids found in proteins (20), so many codons are effectively synonyms. For example, the DNA codons TTT and TTC both code for the amino acid Phenylalanine, so a change from the third T to C makes no difference to the resulting protein. On the other hand, the codon GAG codes for Glutamic acid while the codon GTG codes for Valine, so a change from the middle A to T does change the resulting protein, for better or (more likely) worse, so the change is not a synonym. These changes are illustrated in the tables below. The Ka/Ks ratio measures the relative rates of synonymous and nonsynonymous substitutions at a particular site.
Sources: en.wikipedia.org
Semax is a synthetic seven-amino-acid peptide derived from a fragment of corticotropin. It is used in Russia as a nasal preparation, while elsewhere it is studied as a research compound. It is not approved as a medicine in most countries.
Its sequence corresponds to the 4-10 region of corticotropin extended by three residues. This fragment lacks the region responsible for adrenal steroid release, so it is explored for neural rather than hormonal effects. The relationship explains the compound's classification among ACTH-derived peptides.
It holds approval in Russia for several neurological indications as a nasal spray or drop formulation. Regulatory agencies in the United States and the European Union have not approved it. Products sold elsewhere are generally labeled for research use only.
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.