A practical reference on lyophilised powder: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2026-07-11 and is reviewed periodically as new material appears.
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.
The compound was developed during the 1980s at the Institute of Molecular Genetics in Moscow as part of research on fragments of adrenocorticotropic hormone. Early work examined short ACTH-derived sequences that retained neurotrophic effects while lacking the endocrine activity of the full hormone. Semax entered clinical use in Russia during the 1990s, where it received registration for several neurological indications. Outside that region it remained primarily a laboratory research material rather than an approved therapeutic. English-language literature on it grew more slowly and frequently cited the original Russian studies.
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.
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.
Solid semax is typically supplied as a lyophilised powder that is hygroscopic and sensitive to moisture, light, and repeated temperature cycling. Long-term storage of the dry peptide is generally recommended at approximately -20 degrees Celsius, while shorter working periods may use refrigeration at 2 to 8 degrees Celsius. Vials should remain tightly closed and desiccated when brought to room temperature, because condensation can damage the material before it is weighed. Dividing a batch into aliquots is preferable to thawing one container repeatedly.
| 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.
Clinical evidence consists largely of small trials with modest sample sizes, often without independent replication. Reported endpoints include cognitive scores, recovery after stroke, and visual function, but study designs vary widely and few trials meet contemporary reporting standards. Systematic reviewers have noted a high risk of bias in several of these reports. No large multicenter trial conducted outside Russia has been published. The compound is therefore best described as investigational in most jurisdictions, with its clinical role still unresolved.
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。
== Localization == As a GPI-anchored protein, Thy-1 is present in the outer leaflet of lipid rafts in the cell membrane. In case of neurons it is known to be expressed strongly in the mature axon. The axon hillock can act as a barrier for its lateral spread even though it has no transmembrane segment. Thy-1 has been suggested to interact with G inhibitory proteins, the Src family kinase (SFK) member c-fyn, and tubulin within lipid rafts. In rats and mice, Thy-1 protein is present on the soma (cell body) and dendrites of neurons but is not expressed on axons until axonal growth is complete, and is again temporarily suppressed during axonal injury. HIV-1 Matrix co-localizes with Thy-1 in lipid rafts, the site of virus particle budding from cells, and Thy-1 is incorporated into virus particles as a result of this process.
Metandienone, also known as 17α-methyl-δ1-testosterone or as 17α-methylandrost-1,4-dien-17β-ol-3-one, is a synthetic androstane steroid and a 17α-alkylated derivative of testosterone. It is a modification of testosterone with a methyl group at the C17α position and an additional double bond between the C1 and C2 positions. The drug is also the 17α-methylated derivative of boldenone (δ1-testosterone) and the δ1 analogue of methyltestosterone (17α-methyltestosterone).
The three substrates of this enzyme are the plant steroid curbitacin b, reduced nicotinamide adenine dinucleotide (NADH), and a proton. Its products are dihydrocucurbitacin b, and oxidised NAD+. The enzyme can use nicotinamide adenine dinucleotide phosphate as an alternative cofactor. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-CH group of donor with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is 23,24-dihydrocucurbitacin:NAD(P)+ Delta23-oxidoreductase. This enzyme is also called NAD(P)H: cucurbitacin B Delta23-oxidoreductase. It contains manganese.
Other uses for genetically modified bacteria include bioremediation, where the bacteria are used to convert pollutants into a less toxic form. Genetic engineering can increase the levels of the enzymes used to degrade a toxin or to make the bacteria more stable under environmental conditions. Bioart has also been created using genetically modified bacteria. In the 1980s artist Jon Davis and geneticist Dana Boyd converted the Germanic symbol for femininity (ᛉ) into binary code and then into a DNA sequence, which was then expressed in Escherichia coli. This was taken a step further in 2012, when a whole book was encoded onto DNA. Paintings have also been produced using bacteria transformed with fluorescent proteins.
Sources: en.wikipedia.org
== Regulation == The activity of cysteine proteases is regulated by a few general mechanisms, which includes the production of zymogens, selective expression, pH modification, cellular compartmentalization, and regulation of their enzymatic activity by endogenous inhibitors, which seemingly is the most efficient mechanism associated with the regulation of the activity of cysteine proteases. Proteases are usually synthesized as large precursor proteins called zymogens, such as the serine protease precursors trypsinogen and chymotrypsinogen, and the aspartic protease precursor pepsinogen. The protease is activated by removal of an inhibitory segment or protein. Activation occurs once the protease is delivered to a specific intracellular compartment (for example the lysosome) or extracellular environment (for example the stomach). This system prevents the cell that produces the protease from being damaged by it. Protease inhibitors are usually proteins with domains that enter or block a protease active site to prevent substrate access. In competitive inhibition, the inhibitor binds to the active site, thus preventing enzyme-substrate interaction. In non-competitive inhibition, the inhibitor binds to an allosteric site, which alters the active site and makes it inaccessible to the substrate. Examples of protease inhibitors include:
== Pharmacokinetics == Icodextrin is not significantly metabolised inside the peritoneum. Instead, it is absorbed slowly (40% after 12 hours) into the bloodstream via the lymph vessels. There it is broken down into oligosaccharides by the enzyme alpha-amylase. In patients with intact kidney function, both icodextrin and its fragments are excreted via the kidney by glomerular filtration.
=== Transgenic plant and animals === In recent years, expression vectors have been used to introduce specific genes into plants and animals to produce transgenic organisms, for example in agriculture it is used to produce transgenic plants. Expression vectors have been used to introduce a vitamin A precursor, beta-carotene, into rice plants. This product is called golden rice. This process has also been used to introduce a gene into plants that produces an insecticide, called Bacillus thuringiensis toxin or Bt toxin which reduces the need for farmers to apply insecticides since it is produced by the modified organism. In addition expression vectors are used to extend the ripeness of tomatoes by altering the plant so that it produces less of the chemical that causes the tomatoes to rot. There have been controversies over using expression vectors to modify crops due to the fact that there might be unknown health risks, possibilities of companies patenting certain genetically modified food crops, and ethical concerns. Nevertheless, this technique is still being used and heavily researched. Transgenic animals have also been produced to study animal biochemical processes and human diseases, or used to produce pharmaceuticals and other proteins. They may also be engineered to have advantageous or useful traits. Green fluorescent protein is sometimes used as tags which results in animal that can fluoresce, and this have been exploited commercially to produce the fluorescent GloFish.
== Function == This gene is a member of the insulin-like growth factor binding protein (IGFBP) family and encodes a protein with an IGFBP domain and a thyroglobulin type-I domain. The protein binds both insulin-like growth factors (IGFs) I and II and circulates in the plasma in both glycosylated and non-glycosylated forms. Binding of this protein prolongs the half-life of the IGFs and alters their interaction with cell surface receptors. IGFBP-4 is a unique protein and it consistently inhibits several cancer cells in vivo and in vitro. Its inhibitory action has been shown in vivo in prostate and colon. It is secreted by all colon cancer cells.
Effective vaccines for Haemophilus influenzae serotype b have been available since the early 1990s, and are recommended for children under age 5 and asplenic patients. The World Health Organization recommends a pentavalent vaccine, combining vaccines against diphtheria, tetanus, pertussis, hepatitis B and Hib. There is not yet sufficient evidence on how effective this pentavalent vaccine is in relation to the individual vaccines. Hib vaccines cost about seven times the total cost of vaccines against measles, polio, tuberculosis, diphtheria, tetanus, and pertussis. Consequently, whereas 92% of the populations of developed countries, 94% for European countries, were vaccinated against Hib as of 2023, vaccination coverage was 77% globally, and only 33% for people living in the western pacific region. The Hib vaccines do not provide cross-protection to any other H. influenzae serotypes like Hia, Hic, Hid, Hie or Hif. An oral vaccination has been developed for non-typeable H. influenzae (NTHi) for patients with chronic bronchitis, but it has not shown to be effective in reducing the number and severity of COPD exacerbations. However, there is no effective vaccine for the other types of capsulated H. influenzae or NTHi. Vaccines that target unencapsulated H. influenzae serotypes are in development. By 2026, following the decline of vaccinations in the United States, Hib was confirmed to be making a comeback in the country.
Sources: en.wikipedia.org
=== Ehlers–Danlos syndrome hypermobility type === Joint hypermobility is often correlated with hypermobile Ehlers–Danlos syndrome (hEDS, known also by EDS type III or Ehlers–Danlos syndrome hypermobility type (EDS-HT)). Ehlers–Danlos syndrome is a genetic disorder caused by mutations or hereditary genes, but the genetic defect that produces hEDS is largely unknown. In conjunction with joint hypermobility, a common symptom for hEDS is smooth, velvety, and stretchy skin. When diagnosing hEDS, the Beighton Criteria are used, but are not always able to distinguish between joint hypermobility syndrome and hEDS. Ehlers–Danlos hypermobility type can have severe musculoskeletal effects, including:
Given its conservation throughout evolution, the action potential seems to confer evolutionary advantages. One function of action potentials is rapid, long-range signaling within the organism; the conduction velocity can exceed 110 m/s, which is one-third the speed of sound. For comparison, a hormone molecule carried in the bloodstream moves at roughly 8 m/s in large arteries. Part of this function is the tight coordination of mechanical events, such as the contraction of the heart. A second function is the computation associated with its generation. Being an all-or-none signal that does not decay with transmission distance, the action potential has similar advantages to digital electronics. The integration of various dendritic signals at the axon hillock and its thresholding to form a complex train of action potentials is another form of computation, one that has been exploited biologically to form central pattern generators and mimicked in artificial neural networks. The common prokaryotic/eukaryotic ancestor, which lived perhaps four billion years ago, is believed to have had voltage-gated channels. This functionality was likely, at some later point, cross-purposed to provide a communication mechanism. Even modern single-celled bacteria can utilize action potentials to communicate with other bacteria in the same biofilm.
== Cameroon == Modibbo Adama – Islamic scholar and first emir of Adamawa (Both Cameroon and Nigerian Adamawa) Ahmadou Ahidjo – first president, Cameroon (1960–1982) Bello Bouba Maigari – former prime minister, Cameroon Sadou Hayatou – former prime minister, Cameroon Issa Hayatou – former president of the Confederation of African Football (CAF), former acting president FIFA, Cameroon Oumarou Fadil – Businessman, Vice President of Group Fadil (an agro-industrial group which operates in several sectors including soap, oil extraction, tourism, livestock, and new information technologies), Cameroon Djaili Amadou Amal – Writer and feminist activist, Cameroon Goggo Addi – Storyteller who worked to preserve Fulani cultural heritage Souleymanou Hamidou Germaine Ahidjo - former first lady, Cameroon (1960–1982) Youssoufa Daoua (1947–2015), Cameroonian politician Mohamadou Bayero Fadil, Cameroonian businessman Abbo Aboubakar, Cameroonian businessman and politician Baba Ahmadou Danpullo, Cameroonian businessman Nana Bouba, Cameroonian businessman Marafa Hamidou Yaya, Cameroonian politician Garga Haman Adji, Cameroonian politician Mohamadou Dabo, Cameroonian businessman
Bodhraj Acharya is a Nepalese-born American professional, working in the field of laboratory medicine, Cell Biology and chemistry. He has received many honors, grants and travel fellowships in United States and other countries. He has published patents, abstracts and articles in the field. He had worked previously as a clinical laboratory technical director in various hospitals. He also work as Clinical Laboratory expert for various non-profit organizations.
=== No development reported === ADX-71149 (JNJ-1813; JNJ-40411813; JNJ-mGluR2-PAM) – metabotropic glutamate mGlu2 receptor positive allosteric modulator [5] Tebideutorexant (JNJ-61393215; JNJ-3215) – orexin OX1 receptor antagonist [6]
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.