heptapeptide is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Last reviewed on 2026-01-05. Where a claim depends on a specific study, the study is described rather than over-claimed.
Terminology around the compound varies by source. It appears in catalogues and papers as Semax, as the heptapeptide ACTH(4-7)-Pro-Gly-Pro, and under various alphanumeric laboratory codes used by individual suppliers. These names refer to the same sequence but may imply different salt forms, purity grades, or counter-ions. Peptide databases usually list the free base mass, while product descriptions sometimes report acetate or trifluoroacetate salts with a different formula weight. Because naming conventions for research peptides are not standardised across vendors, checking the declared sequence and measured mass is more reliable than relying on a trade name alone.
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.
Purity assessment relies mainly on reversed-phase high-performance liquid chromatography, which separates the target heptapeptide from truncated sequences, deletion analogues, and oxidised forms. Mass spectrometry, usually coupled to liquid chromatography, confirms identity through the expected molecular ion and reveals modifications such as methionine sulfoxide formation. Amino acid analysis can verify composition, and tandem mass spectrometry supports sequence confirmation. Ultraviolet detection near 254 to 280 nanometres is convenient because the phenylalanine and histidine residues absorb in that region. Nuclear magnetic resonance is rarely used for routine release testing.
Common degradation pathways include oxidation of the methionine side chain, hydrolysis of the peptide backbone, and aggregation under unfavourable pH or concentration. Stability studies typically monitor the main peak by chromatography and report total related substances as a percentage. Because no official monograph exists, acceptance criteria vary between laboratories, and reported purity values are not directly comparable across suppliers. Analysts therefore document the method, column, and detection wavelength alongside each result, and open questions remain about how much biological activity the oxidised forms retain.
| 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 |
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.
常规纯度与身份确认依赖反相高效液相色谱，并辅以质谱测定分子量。氨基酸组成分析可用于验证序列构成，肽图分析则能进一步定位修饰或降解产物。杂质谱通常关注缺失序列肽、截短片段和氧化产物。不同方法的检出限并不相同，因此各实验室报告的纯度数值不宜直接横向比较。
多数实验室与市售的 Semax 以冻干粉形式提供。冻干粉通常建议保存在 -20 °C 或更低温度下，同时避免光照与反复升温。短期运输有时采用冷藏条件，但长期保存仍以冷冻为主。分包操作应尽量减少开盖次数，以降低吸湿和微生物污染的风险。开封后若未一次用完，建议在干燥环境中密封并尽快放回低温储存。
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.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It corresponds to the ACTH(4-7) fragment extended at the C-terminus by a Pro-Gly-Pro tripeptide, an addition intended to slow enzymatic breakdown. The molecular formula is C37H51N9O10S and the molecular mass is approximately 814 daltons. In the literature it is often described as an ACTH(4-10) analog, although that label reflects a naming convention as much as a precise structural relationship. The compound was developed in Russia and remains most closely associated with that research tradition.
纯度评估以反相高效液相色谱为主，通过主峰面积百分比给出粗略结果，再配合电喷雾质谱核对分子量。氨基酸分析可验证组成比例，手性色谱或毛细管电泳用于检查残基构型。常见杂质包括缺失序列的短肽、氧化产物与二聚体。由于多数市售品不附带完整检验报告，独立第三方检测常被用来核实标称值。
从分子层面看，Semax 是线性七肽，没有二硫键、糖基或脂链修饰，N 端为游离氨基，C 端为游离羧基。分子含组氨酸与谷氨酸侧链，因此在水和甲醇等极性溶剂中溶解良好，在非极性溶剂中溶解有限。计算分子量约为 814 Da，与其质子化离子的质荷比吻合，可用于质谱确认。
On 10 November 1952 Thomas's last collection Collected Poems, 1934–1952, was published by Dent; he was 38. It won the Foyle poetry prize. Reviewing the volume, critic Philip Toynbee declared that "Thomas is the greatest living poet in the English language". The winter of 1952/3 brought much personal tragedy: Thomas's father died from pneumonia just before Christmas 1952; and in the Spring of 1953 his sister died from liver cancer, one of his patrons overdosed, three friends died at young ages and Caitlin had an abortion.
=== RLM designations === Focke-Wulf Fw 40 short-range reconnaissance parasol monoplane (prototype), 1932; known internally as A 40. Focke-Wulf Fw 43 Falke (Falcon) – utility aircraft (prototype), 1932; known internally as A 43. Focke-Wulf Fw 44 Stieglitz (Goldfinch) – trainer (biplane), 1932. Focke-Wulf Fw 47 Höhengeier (Vulture) – weather aircraft, 1931; known internally as A 47. Focke-Wulf Fw 55 – biplane floatplane derived from the Albatros L102, 1932. Focke-Wulf Fw 56 Stösser (Goshawk) – advanced trainer (parasol monoplane), 1933 Focke-Wulf Fw 57 – twin-engined heavy fighter-bomber (prototype), 1935. Focke-Wulf Fw 58 Weihe (Kite) – transport/photo reconnaissance/weather research aircraft, 1937. Focke-Wulf Fw 61 – helicopter (prototype), 1936. Focke-Wulf Fw 62 – ship-borne reconnaissance (biplane seaplane), 1937. Focke-Wulf Ta 152 – interceptor/fighter (derived from Fw 190), 1944. Focke-Wulf Ta 154 Moskito (Mosquito) – night-fighter with wood structure like its British namesake, 1943. Focke-Wulf Fw 159 – fighter (prototype only), 1935. Focke-Wulf Fw 186 – autogiro reconnaissance aircraft (prototype), 1937. Focke-Wulf Fw 187 Falke (Falcon) – twin-engined two-seat heavy day fighter ("Zerstörer"), 1936. Focke-Wulf Fw 189 Uhu (Eagle Owl) – twin-engined, three-seat army cooperation/tactical reconnaissance, 1938. Focke-Wulf Fw 190 Würger (Shrike/butcher-bird) – single-seat fighter/interceptor, 1939 Focke-Wulf Fw 191 – twin-engine Bomber B design competitor (prototype), 1942. Focke-Wulf Fw 200 Condor – four-engine airliner and maritime patrol-bomber, 1937.
== Treatment == There is no definitive treatment for hyperandrogenism as it varies with the underlying condition that causes it. As a hormonal symptom of PMOS, menopause, and other endocrine conditions, it is primarily treated as a symptom of these conditions. Drugs may be considered only in women who do not plan on becoming pregnant in the near future. Some effective drugs for facial hirsutism includes eflornithine, which may cause birth defects in pregnant women. Retinoids and antibiotics can be used for acne and minoxidil for alopecia. Systemically, it is treated with antiandrogens such as cyproterone acetate, flutamide and spironolactone to reduce androgenic signaling. For hyperandrogenism caused by late-onset congenital adrenal hyperplasia (LOCAH), treatment is primarily focused on providing the patient with glucocorticoids to combat the low cortisol production and the corresponding increase in androgens caused by the increase in size of the adrenal glands. Estrogen-based oral contraceptives are used to treat both LOCAH- and PMOS-associated hyperandrogenism. These hormonal treatments reduce the androgen excess and suppress adrenal androgen production, bringing about a significant decrease in hirsutism. Hyperandrogenism is often managed symptomatically. Hirsutism and acne both respond well to the hormonal treatments described above, with 60–100% of patients reporting an improvement in hirsutism. Androgenic alopecia however, does not show an improvement with hormonal treatments and requires other treatments, such as hair transplantation.
TFEU art 248 says the president may reshuffle commissioners, though this is uncommon, without member state approval. A proposal that the commissioners be drawn from the elected Parliament, was not adopted in the Treaty of Lisbon, though in practice several invariable are, relinquishing their seat in order to serve. Commissioners have various privileges, such as being exempt from member state taxes (but not EU taxes), and having immunity from prosecution for doing official acts. Commissioners have sometimes been found to have abused their offices, particularly since the Santer Commission was censured by Parliament in 1999, and it eventually resigned due to corruption allegations. This resulted in one main case, Commission v Edith Cresson where the European Court of Justice held that a Commissioner giving her dentist a job, for which he was clearly unqualified, did in fact not break any law. By contrast to the ECJ's strictly legalistic approach, a Committee of Independent Experts found that a culture had developed where few Commissioners had 'even the slightest sense of responsibility'. This led to the creation of the European Anti-fraud Office. In 2012, it investigated the Maltese Commissioner for Health, John Dalli, who quickly resigned after allegations that he received a €60m bribe in connection with a Tobacco Products Directive. Beyond the commission, the European Central Bank has relative executive autonomy in its conduct of monetary policy for the purpose of managing the euro.
Sources: en.wikipedia.org
It is not clear if this term refers to IRP, rectal mucosal prolapse, or a mucosal prolapse which does not protrude externally. Mucosal prolapse has been defined as infolding of less than 3 mm of the thickness of the rectal wall. If the thickness of the prolapsed segment is more than 3 mm, the term intussusception is used.
== In Archaea == In archaea, RNase P ribonucleoproteins consist of 4–5 protein subunits that are associated with RNA. As revealed by in vitro reconstitution experiments these protein subunits are individually dispensable for tRNA processing that is essentially mediated by the RNA component. The structures of protein subunits of archaeal RNase P have been resolved by x-ray crystallography and NMR, thus revealing new protein domains and folding fundamental for function. Using comparative genomics and improved computational methods, a radically minimized form of the RNase P RNA, dubbed "Type T", has been found in all complete genomes in the crenarchaeal phylogenetic family Thermoproteaceae, including species in the genera Pyrobaculum, Caldivirga and Vulcanisaeta. All retain a conventional catalytic domain, but lack a recognizable specificity domain. 5′ tRNA processing activity of the RNA alone was experimentally confirmed. The Pyrobaculum and Caldivirga RNase P RNAs are the smallest naturally occurring form yet discovered to function as trans-acting ribozymes. Loss of the specificity domain in these RNAs suggests potential altered substrate specificity. It has recently been argued that the archaebacterium Nanoarchaeum equitans does not possess RNase P. Computational and experimental studies failed to find evidence for its existence. In this organism the tRNA promoter is close to the tRNA gene and it is thought that transcription starts at the first base of the tRNA thus removing the requirement for RNase P.
The Green Chemistry Institute (GCI) supports the "implementation of green chemistry and engineering throughout the global chemistry enterprise." The GCI organizes an annual conference, the Green Chemistry and Engineering Conference, provides research grants, administers awards, and provides information and support for green chemistry practices to educators, researchers, and industry. The GCI was founded in 1997 as an independent non-profit organization, by chemists Joe Breen and Dennis Hjeresen in cooperation with the Environmental Protection Agency. In 2001, the GCI became a part of the American Chemical Society.[1]
== Research == Ibogaine has been studied for its potential medical use in treating substance use disorders, particularly opioid addiction, by reducing withdrawal symptoms and cravings. Regulatory restrictions and serious safety concerns, including cardiac risks, have limited its clinical development.
== Chemistry and mechanism of action == Teduglutide differs from natural GLP-2 by a single amino acid: an alanine is replaced with a glycine. This blocks breaking down of the molecule by dipeptidyl peptidase and increases its half-life from seven minutes (GLP-2) to about two hours, while retaining its biological actions. These include maintenance of the intestinal mucosa, increasing intestinal blood flow, reducing gastrointestinal motility and secretion of gastric acid.
Sources: en.wikipedia.org
Anti-Peruvian (Spanish: Antiperuanismo), or Peruvophobia, refers to negative feelings, fear, hatred and discrimination toward and/or against Peruvians based on a combination of historical, cultural, and ethnic prejudices. It arose since the 19th century in some societies as a consequence of their territorial expansion. It germinated as a tendency in the nationalisms of neighboring countries, mainly Ecuador, Chile and to a lesser extent due to the disputed origin of different cultural manifestations, such as recipes and gastronomic preparations (such as pisco or picarones) or folkloric dances (such as the diablada or the morenada) whose origin is disputed or shared with Chile and Bolivia. In addition, due to different political and ideological differences with the Bolivarian leaders and their Chavista sympathizers in Venezuela. It can manifest itself in many ways, such as individual hatred or discrimination, tabloid media, attacks by groups organized for that purpose, even on social networks.
In 2010, over 136 students graduated with degree or diploma. In 2013, 347 students graduated with degree or diploma, of whom 31% were female. In 2014, 477 students graduated with degree or diploma, of whom 34% were female. In 2015, 416 students graduated with degree or diploma, of whom 40% were female. In 2016, 367 students graduated with degree or diploma, of whom 40% were female. in 2018, 459 students graduated with degree or diploma. In 2013, the number of the students was reported as increasing by more than 10% each year.
=== Oral cavity === Amyloid deposits in tissue can cause enlargement of structures. Twenty percent of people with AL amyloidosis have an enlarged tongue, that can lead to obstructive sleep apnea, difficulty swallowing, and altered taste. Tongue enlargement does not occur in ATTR or AA amyloidosis. Deposition of amyloid in the throat can cause hoarseness.
A serotonin reuptake inhibitor (SRI) is a type of drug which acts as a reuptake inhibitor of the neurotransmitter serotonin (5-hydroxytryptamine, or 5-HT) by blocking the action of the serotonin transporter (SERT). This in turn leads to increased extracellular concentrations of serotonin and, therefore, an increase in serotonergic neurotransmission. It is a type of monoamine reuptake inhibitor (MRI); other types of MRIs include dopamine reuptake inhibitors and norepinephrine reuptake inhibitors. SRIs are not synonymous with selective serotonin reuptake inhibitors (SSRIs), as the latter term is usually used to describe the class of antidepressants of the same name, and because SRIs, unlike SSRIs, can either be selective or non-selective in their action. For example, cocaine, which non-selectively inhibits the reuptake of serotonin, norepinephrine, and dopamine, is an SRI but not an SSRI. SRIs are used predominantly as antidepressants (e.g., SSRIs, SNRIs, and TCAs), though they are also commonly used in the treatment of other psychological conditions such as anxiety disorders and eating disorders. Less often, SRIs are also used to treat a variety of other medical conditions including neuropathic pain and fibromyalgia (e.g., duloxetine, milnacipran), and premature ejaculation (e.g., dapoxetine) as well as for dieting (e.g., sibutramine).
== Pathology == Haptotaxis plays a role in several kinds of diseases where the movement or aggregation of cells causes the symptoms. As mentioned before, cancers that are metastatic have the ability to perform haptotaxis in order to spread throughout the body. This ability is not limited to tumor cells. Idiopathic pulmonary fibrosis (IPF) is a disease marked by fibrosis in lung mesothelial cells. TGF-β1 is a cytokine found in higher concentrations of lungs from patients who have IPF, and induces haptotaxis of pleural mesothelial cells. At the same time, TGF-β1 causes the mesothelial cells to develop into myofibroblasts, which contribute to the symptoms in IPF. The result is that there becomes an aggregation of myofibroblasts in the lungs, which leads to fibrosis of the mesothelial cells. During nephritis, VCAM-1 is expressed in higher levels on the tubules of nephrons, which leads to increased leukocyte migration via the gradient established by VCAM-1. This increased expression was not found on the capillary endothelial cells. This migration of leukocytes leads to inflammation and tissue destruction characteristic of an inflammatory response.
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.
Dry powder is usually kept at about -20 degrees Celsius for long-term storage and at 2 to 8 degrees Celsius for short working periods. Containers should stay sealed and protected from light and moisture to limit degradation.