Everything below concerns Electrospray ionization. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2026-06-25. Where a claim depends on a specific study, the study is described rather than over-claimed.
Semax binds to melanocortin receptors and is thought to influence neuronal survival and plasticity rather than to act through the adrenal axis. Laboratory work has shown increased expression of brain-derived neurotrophic factor and nerve growth factor in treated tissue. Changes in c-Fos, a marker of neuronal activation, have also been reported. Because the peptide is rapidly degraded by peptidases, its effects are generally attributed to downstream signaling cascades rather than to sustained receptor occupancy.
Published studies are dominated by animal models of stroke, ischemia, and cognitive impairment, with a smaller number of human trials conducted in Russia. Many of the human reports are small, single-center, and published in Russian-language journals, which limits independent scrutiny. Outcome measures vary between studies and often rely on clinician-rated scales rather than objective biomarkers. Systematic reviews have noted the methodological weaknesses and called for larger, preregistered trials before firm conclusions can be drawn.
Claims about enhanced focus, memory, or mood in healthy people rest mostly on anecdotal reports and community discussion rather than on controlled data. It remains unclear whether any cognitive benefit observed in patients recovering from brain injury would extend to uninjured users. Dose-response relationships, long-term safety, and interactions with other drugs are not well characterized in the peer-reviewed literature. Questions about optimal route of administration and treatment duration likewise remain open.
该化合物于二十世纪八十年代在俄罗斯被开发，相关工作由俄罗斯科学院分子遗传学研究所的研究团队主导。开发目标并非复制 ACTH 的完整激素活性，而是寻找保留其神经作用方向、同时去除促肾上腺皮质激素释放效应的短肽片段。研究记录显示，这一方向促成了多个相关短肽的合成与筛选，而 Semax 是其中被研究最广泛的一个。当地文献常以 Семакс 这一名称指代它。
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。
| Property | Value | Notes |
|---|---|---|
| Appearance | White lyophilized powder | Typical for synthetic peptides |
| Solubility | Freely soluble in water | Also soluble in saline |
| Storage temperature | -20 C or below | Protect from repeated freeze-thaw |
| Analytical method | Reverse-phase HPLC | Confirms purity and identity |
| Common synonym | ACTH(4-10) analog | Reflects structural origin |
Lyophilized material is chemically stable for extended periods when kept dry, cold, and protected from light. The powder is hygroscopic, so vials should be warmed to room temperature before opening to reduce condensation on the contents. Once dissolved, the peptide is far less stable because peptide bonds are susceptible to hydrolysis and the methionine residue can oxidize. Solutions are typically aliquoted and held at 2-8 °C for short intervals or frozen for longer ones, and repeated freeze-thaw cycles should be avoided.
Routine characterization relies on reversed-phase high-performance liquid chromatography to establish purity and on mass spectrometry to confirm molecular identity. Electrospray ionization and matrix-assisted laser desorption ionization are both used for mass verification. Amino acid analysis and peptide mapping can detect sequence errors. Common impurities include truncated sequences, methionine sulfoxide formed by oxidation, and deamidated products. Chromatograms are usually recorded near 214 nm, where the peptide backbone absorbs, and purity is reported as the percentage area of the principal peak.
Verification of a supplied batch generally combines a certificate of analysis with independent testing, because certificates are self-reported documents. A typical package includes a chromatographic trace, a mass spectrum, and a stated water or counter-ion content. Batch-to-batch consistency matters more than a single purity figure when results are compared across experiments. No single mandatory standard governs research-grade peptide release, so laboratories are expected to define their own acceptance criteria. Residual trifluoroacetate from purification is a frequently overlooked counter-ion.
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.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Its chain combines the first seven residues of corticotropin with a C-terminal proline-glycine-proline extension, a modification intended to slow enzymatic breakdown. The free peptide has a molecular mass near 813.9 daltons. It belongs to the class of ACTH-derived fragments studied for central nervous system activity rather than for adrenal steroid stimulation. This structural relationship to a natural hormone fragment is the usual starting point for describing the compound in the literature.
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.
Identity and purity of Semax are established mainly by reversed-phase high-performance liquid chromatography coupled with mass spectrometry. The chromatographic trace gives a purity estimate as a percentage of total peak area, while electrospray or matrix-assisted laser desorption ionization confirms the molecular mass against the calculated value. Amino acid analysis and sequence-specific fragmentation provide further confirmation when a supplier's chain of custody is unclear. Vendors frequently quote a purity figure without stating the detection wavelength or the integration method, which limits how far one number can be compared with another.
Stability depends heavily on physical state. Lyophilized powder held dry, cold and dark retains its content over long periods, whereas dissolved peptide begins to change within days at room temperature. The most cited degradation route is oxidation of the methionine residue, which converts the peptide to a sulfoxide form that elutes differently on chromatography. Hydrolysis of amide bonds and adsorption onto container walls contribute smaller losses. Buffers that exclude oxygen from the headspace slow the oxidation pathway, but no single condition prevents all change indefinitely.
Practical handling follows from those properties. Bulk material is best divided into single-use portions soon after receipt, because each thaw exposes the whole container to moisture and temperature cycling. Vials should be allowed to reach room temperature before opening to prevent condensation on the powder. Low-binding plasticware reduces loss of dilute solutions, and sterile filtration is used when a preparation must remain free of microbial growth. Records of batch number, reconstitution date and storage history are what allow a later analytical result to be interpreted meaningfully.
Elastin is a protein encoded by the ELN gene in humans and several other animals. Elastin is a key component in the extracellular matrix of gnathostomes (jawed vertebrates). It is highly elastic and present in connective tissue of the body to resume its shape after stretching or contracting. Elastin helps skin return to its original position when poked or pinched. Elastin is also in important load-bearing tissue of vertebrates and used in places where storage of mechanical energy is required.
== Usefulness of NTX as a biomarker == Evaluating an individual's rate of bone turnover, termed bone remodeling, directly may be important in assessing his or her potential nonsurgical treatment response as well as evaluating his or her risk of developing complications during healing following surgical intervention. To determine an individual's rate of bone turnover, numerous biomarkers are available in the body fluids that can be correlated to this rate, and one such biomarker is NTX. However, while NTX does fluctuate in a very sensitive manner in line with bone resorption patterns, they are not very specific, in that they may vary spontaneously without physiologic intervention. For example, NTX levels may drop by 50% from day to day with no treatment, thus, making NTX levels unconvincing evidence of treatment effect. Conversely, the serum CTX biomarker, described in 2000 by Rosen, appears to be a much more effective and valuable indicator of bone resorption rate.
Underworld is a 2003 action horror film directed by Len Wiseman in his feature film directorial debut, from a screenplay by Danny McBride, based on a story by Kevin Grevioux, Wiseman, and McBride. The film stars Kate Beckinsale, Scott Speedman, Michael Sheen, Shane Brolly, Erwin Leder, and Bill Nighy. The plot centers on the secret history of vampires and lycans (an abbreviated form of lycanthrope, which means werewolf). The main plot revolves around Selene (Beckinsale), a vampire Death Dealer hunting Lycans. She finds herself attracted to a human, Michael Corvin (Speedman), who is being targeted by the Lycans. After Michael is bitten by a Lycan, Selene must decide whether to do her duty and kill him or go against her clan and save him. Underworld premiered at the Grauman's Chinese Theatre in Los Angeles, California on September 15, 2003, and was released in the United States on September 19, by Sony Pictures Releasing under the Screen Gems banner. The film received generally mixed-to-negative reviews from critics. A surprise hit, the film grossed over $95 million worldwide against a production budget of $22 million and originated a franchise. The film was followed by Underworld: Evolution in 2006.
=== Perception === Machine perception is the ability to use input from sensors (such as cameras, microphones, wireless signals, active lidar, sonar, radar, and tactile sensors) to deduce aspects of the world. Computer vision is the ability to analyse visual input. The field includes speech recognition, image classification, facial recognition, object recognition, object tracking, and robotic perception.
Sources: en.wikipedia.org
== Function == In the heart, specialized cardiac muscle cells transmit electrical impulses from the atrioventricular node (AV node) to the Purkinje fibers – fascicles, also referred to as bundle branches. These start as a single fascicle of fibers at the AV node called the bundle of His that then splits into three bundle branches: the right fascicular branch, left anterior fascicular branch, and left posterior fascicular branch.
== Prediction == Because viscosity depends continuously on temperature and pressure, it cannot be fully characterized by a finite number of experimental measurements. Predictive formulas become necessary if experimental values are not available at the temperatures and pressures of interest. This capability is important for thermophysical simulations, in which the temperature and pressure of a fluid can vary continuously with space and time. A similar situation is encountered for mixtures of pure fluids, where the viscosity depends continuously on the concentration ratios of the constituent fluids For the simplest fluids, such as dilute monatomic gases and their mixtures, ab initio quantum mechanical computations can accurately predict viscosity in terms of fundamental atomic constants, i.e., without reference to existing viscosity measurements. For the special case of dilute helium, uncertainties in the ab initio calculated viscosity are two order of magnitudes smaller than uncertainties in experimental values. For slightly more complex fluids and mixtures at moderate densities (i.e. sub-critical densities) Revised Enskog Theory can be used to predict viscosities with some accuracy. Revised Enskog Theory is predictive in the sense that predictions for viscosity can be obtained using parameters fitted to other, pure-fluid thermodynamic properties or transport properties, thus requiring no a priori experimental viscosity measurements. For most fluids, high-accuracy, first-principles computations are not feasible.
Edelin (1961), physician known for his support of abortion rights; former chairman of Planned Parenthood Eugene Milone (1961), astronomer, professor at the University of Calgary Robert Pollack (1961), biologist who studies the intersections between science and religion Samuel Strober (1961), immunologist at Stanford Medical School, co-founder of Dendreon Charles Cantor (1962), molecular geneticist; chief science officer at Sequenom Armando Favazza (1962), author and psychiatrist at the University of Missouri Stephen Larsen (1962), psychologist and founding board member of the Joseph Campbell Foundation Robert Lefkowitz (1962), winner of the Nobel Prize in Chemistry Jeffrey Mandula (1962), physicist known for the Coleman–Mandula theorem Allen Neuringer (1962), psychologist, prominent in the field of the experimental analysis of behavior Farhad Ardalan (1963), Iranian high energy physicist and professor at Sharif University and the Institute for Studies in Theoretical Physics and Mathematics. Harvey Cantor (1963), immunologist, professor of microbiology & immunobiology at Harvard Medical School David B. Cohen (1963), psychologist, professor at the University of Texas at Austin Allen Frances (1963), psychiatrist at Duke University; founding editor of the Journal of Personality Disorders and Journal of Psychiatric Practice David George Hitlin (1963), physicist at the California Institute of Technology Michael Lubell (1963), physicist, professor of the City College of New York Kenneth X.
Sources: en.wikipedia.org
=== Legal status === Cipaglucosidase alfa is available in the UK, since June 2021, under the Early Access to Medicines Scheme. In December 2022, the Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency (EMA) adopted a positive opinion, recommending the granting of a marketing authorization for the medicinal product Pombiliti, intended for the treatment of glycogen storage disease type II (Pompe disease). The applicant for this medicinal product is Amicus Therapeutics Europe Limited. Cipaglucosidase alfa was approved for medical use in the European Union in March 2023.
== Dehydration methods == People have practiced food preservation since ancient times. Many folktales describe ways of preserving foods in one way or another according to local and cultural traditions. Dehydration methods help to prevent food from spoilage and to maintain it for a longer period of time while keeping it suitable for consumption. Reducing the amount of water in fruits helps prevent growth of bacteria, yeast or fungi. There are several processes that can be used in the production of dried fruit, each of which affects its appearance, rehydration properties, and nutrients differently. These drying processes include sun drying, tray (air) drying, freeze drying, and vacuum microwave drying. Each process has advantages and disadvantages.
== See also == Avogadro's law – Relationship between volume and amount of a gas at constant temperature and pressure Boyle's law – Relation between gas pressure and volume Charles's law – Relationship between volume and temperature of a gas at constant pressure Combined gas law – Combination of Charles', Boyle's and Gay-Lussac's gas laws
In 2024, D'Souza criticized the International Olympic Committee (IOC), alleging institutional corruption and inadequate athlete compensation. He also advocated for the abolition of the World Anti-Doping Agency (WADA), characterizing it as an "anti-science" extension of the IOC. D'Souza also argued that the Olympic program includes insignificant sports. He states that he has never used performance-enhancing drugs himself. By late 2025, he had been replaced as chief executive by Maximilian Martin, investment banker and bitcoin miner. Olympians attached to the organisation as of 2023 include Brett Fraser, Roland Schoeman, and Christina Smith. In 2025, Brett Hawke was named head swim coach. Other people include geneticist George Church. German biotech billionaire Christian Angermayer is co-founder of the organisation. D'Souza became Thiel's confidant in the process of leading the Gawker plan for him, and through Thiel's introduction, a friend of Angermayer. According to The Spectator, in December 2022, as D'Souza and other members of their small community of gay tech founders were about to gather for the annual party at Thiel's residence in Miami (formerly held while travelling the world, until Thiel had children), D'Souza came up with the idea of the Enhanced Games. After receiving positive feedback from Thiel (while other investors thought that the idea was "outside the Overton window"), D'Souza spent the next six months developing the project. Later, after reading about the plan on German media, Angermayer notified D'Souza that he wanted to come on board as a co-founder.
Sources: en.wikipedia.org
It is associated with the melanocortin receptor family, particularly subtypes found in the central nervous system. This interaction is separate from the adrenal pathway activated by full-length ACTH.
Peptidases degrade the compound within minutes in circulation. This short half-life is one reason nasal delivery is used, placing the substance close to the olfactory and trigeminal pathways.
No large multicenter trials have been published in English-language journals. The existing human evidence consists mainly of smaller studies conducted in Russia, which limits generalization.
不是。Semax 是完全人工合成的七肽，自然界中没有对应的已知肽段。它的设计灵感来自促肾上腺皮质激素片段 ACTH(4-10)，但序列经过了替换和延长。