Everything below concerns lyophilized powder. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2026-06-08. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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.
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 |
|---|---|---|
| Molecular formula | C37H51N9O10S | Contains one methionine sulfur atom |
| Molecular mass | Approximately 814 Da | Consistent with a seven-residue peptide |
| Appearance | White to off-white powder | Typical lyophilized form |
| Solubility | Freely soluble in water | Also soluble in dimethyl sulfoxide |
| Typical storage | -20 °C, desiccated | Limits methionine oxidation |
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.
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。
=== Post-translational modifications and cofactors === Phosphorylation of the N-terminus not only prevents MDM2 binding but also facilitates the recruitment of cofactors. Pin1 enhances conformational changes in p53, while p300 and PCAF acetylate the C-terminus, exposing the DNA-binding domain and enhancing transcriptional activation. Conversely, deacetylases such as Sirt1 and Sirt7 remove these modifications, suppressing apoptosis and promoting cell survival. Some oncogenes can also activate p53 indirectly by inhibiting MDM2.
== Selected honors == Elected member, American Society for Clinical Investigation (1990) Outstanding Investigator Award for Clinical Research, AFCR (1995) Master of Arts (honorary), Yale University Outstanding Scientific Achievement Award, American Diabetes Association (1997) Diabetes Care Research Award, JDRF International (1997) Elected to the Association of American Physicians (1997) Elected Fellow of the International Society of Magnetic Resonance in Medicine (1998) Novartis Investigator Prize in Diabetes (1999) E.H. Ahrens Jr. Award, Association for Patient-Oriented Research (2001) Yamanouchi USA Foundation Award (2003) Distinguished Clinical Scientist Award, American Diabetes Association (2004) Elected to the National Academy of Medicine (2005) Elected to the National Academy of Sciences (2007) Naomi Berrie Award for Outstanding Diabetes Research, Columbia University (2007) Stanley J.
=== Precambrian bodies === The Earth formed around 4.6 billion years ago, with unicellular life emerging somewhat later after the cessation of the Late Heavy Bombardment, a period of intense asteroid impacts possibly caused by migration of the gas giant planets to their current orbits, however multicellularity and bodies are a relatively recent event in Earth's history. Bodies first started appearing towards the end of the Precambrian Era, during the Ediacaran period. The fossils of the Ediacaran period were first found in Southern Australia in the Ediacara Hills, hence the name. However these fossils were initially thought to be part of the Cambrian and it wasn't until the late 1950s when Martin Glaessner identified the fossils as actually being from the Precambrian era. The fossils that were found date to about 600 million years ago and are found in a variety of morphologies.
What a terrible shame. It would be easy for me to get in a back room with this man's lawyer and make this go away, but there are some moments in life when you have to stand up and defend your honor against the evil in this world. I will not tolerate this heartless attempt to exploit me or the woman I loved. Cat's troubles were born long before I met her and sadly her tragic end was beyond anyone's control. I really hope that some day soon people will stop trying to profit from this and let her rest in peace. In October 2016, White's mother, Brigid Sweetman, also filed a wrongful death lawsuit against Carrey. Both lawsuits were dismissed on January 25, 2018, and attorneys for both sides confirmed there would be no further legal proceedings.
Sources: en.wikipedia.org
The inhibition of lipogenesis occurs through the down regulation of fatty acid and triglyceride gene expression. Through the promotion of fatty acid oxidation and lipogenesis inhibition, leptin was found to control the release of stored glucose from adipose tissues. Other hormones that prevent the stimulation of lipogenesis in adipose cells are growth hormones (GH). Growth hormones result in loss of fat but stimulate muscle gain. One proposed mechanism for how the hormone works is that growth hormones affects insulin signaling thereby decreasing insulin sensitivity and in turn down regulating fatty acid synthase expression. Another proposed mechanism suggests that growth hormones may phosphorylate with STAT5A and STAT5B, transcription factors that are a part of the Signal Transducer And Activator Of Transcription (STAT) family. There is also evidence suggesting that acylation stimulating protein (ASP) promotes the aggregation of triglycerides in adipose cells. This aggregation of triglycerides occurs through the increase in the synthesis of triglyceride production.
In 2006, a toxic waste spill off the coast of Côte d'Ivoire, from a European ship, prompted the commission to look into legislation against toxic waste. Environment Commissioner Stavros Dimas stated that "Such highly toxic waste should never have left the European Union". With countries such as Spain not even having a crime against shipping toxic waste, Franco Frattini, the Justice, Freedom and Security Commissioner, proposed with Dimas to create criminal sentences for "ecological crimes". The competence for the Union to do this was contested in 2005 at the Court of Justice resulting in a victory for the commission. That ruling set a precedent that the commission, on a supranational basis, may legislate in criminal law – something never done before. So far, the only other proposal has been the draft intellectual property rights directive. Motions were tabled in the European Parliament against that legislation on the basis that criminal law should not be an EU competence, but was rejected at vote. However, in October 2007, the Court of Justice ruled that the commission could not propose what the criminal sanctions could be, only that there must be some.
== Prognosis == The cutaneous manifestations of dermatomyositis may or may not improve with therapy in parallel with the improvement of the myositis. In some people, the weakness and rash resolve together. In others, the two are not linked, with one or the other being more challenging to control. Often, cutaneous disease persists after adequate control of the muscle disease. The risk of death from the condition is much higher if the heart or lungs are affected. Before the advent of modern therapies, the prognosis was poor. However, with timely diagnosis and appropriate management, the prognosis has improved substantially, and outcomes are now generally favorable.
is the area of the surface on contact. Pressure is a scalar quantity. It relates the vector area element (a vector normal to the surface) with the normal force acting on it. The pressure is the scalar proportionality constant that relates these two normal vectors:
Leptin plays a critical role in the adaptive response to starvation. Leptin level is decreased after short-term fasting (24–72 hours), even when changes in fat mass are not observed. Serum level of leptin is reduced by sleep deprivation. Leptin levels are paradoxically increased in obesity. Leptin level is increased by emotional stress. Leptin level is chronically reduced by physical exercise training. Leptin level is decreased by increases in testosterone levels and increased by increases in estrogen levels. Leptin level is increased by insulin. Leptin release is increased by dexamethasone. In obese patients with obstructive sleep apnea, leptin level is increased, but decreased after the administration of continuous positive airway pressure. In non-obese individuals, however, restful sleep (i.e., 8–12 hours of unbroken sleep) can increase leptin to normal levels.
Sources: en.wikipedia.org
It is registered as a pharmaceutical product in Russia, where it is typically supplied as a nasal solution. In most other countries it is not an approved drug and is traded as a research chemical instead. Approval status depends entirely on the jurisdiction involved.
Most published work uses intranasal administration, matching the route of the registered Russian formulation. Some animal experiments use intravenous or intraperitoneal injection. The route matters because the intact peptide is cleared rapidly from blood, so exposure differs between methods.
A purity value describes the share of the powder accounted for by the target peptide, usually by high-performance liquid chromatography. It does not confirm that the sequence is correct, which requires mass spectrometry or amino acid analysis. Purity and identity are separate checks.
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.