intranasal delivery 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 2025-12-08. Numbers and descriptions here follow the published literature rather than marketing material.
The mechanisms attributed to semax are inferred from animal and cell studies rather than traced to one confirmed target. The most frequently cited pathway involves increased expression of brain-derived neurotrophic factor and nerve growth factor in hippocampal and cortical tissue. Some work points to engagement of melanocortin receptors, particularly MC4, which the parent ACTH fragment can activate. Effects on dopaminergic and serotonergic signalling have also been reported. No single account explains all observed results, and the relative weight of each pathway remains unsettled.
Published studies examine a fairly narrow set of endpoints. Rodent experiments commonly measure maze learning, infarct volume after induced ischemia, and tissue levels of neurotrophic factors. Clinical reports from Russian centres describe attention, memory and recovery scores in patients after stroke or transient ischemic attack. Most of those human studies are small and few have been repeated by independent groups. Outcome measures differ between studies, which limits direct comparison.
Circulation time for the peptide is short because peptidases cleave it readily. The Pro-Gly-Pro tail is thought to slow breakdown compared with the bare ACTH fragment, but the gain appears modest. Absorption after intranasal dosing is limited, and only a fraction of a dose is expected to reach the central nervous system. Laboratory concentrations therefore sit well above levels achieved systemically, a gap that complicates translation from bench findings to clinical claims.
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。
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 to off-white powder | Lyophilized solid from research suppliers |
| Solubility | Freely soluble in water | Also dissolves in aqueous buffers; solutions are used fresh |
| Typical storage temperature | -20 °C for lyophilized powder | Short-term transport at 2-8 °C is common |
| Common analytical method | Reverse-phase HPLC | Paired with mass spectrometry for identity confirmation |
| Common synonyms | ACTH(4-10) analogue; MEHFPGP | N-terminal methionine retained in the chain |
The peptide is prone to several degradation pathways. Oxidation of the methionine residue produces a sulfoxide that elutes close to the parent peak in many chromatographic systems. Hydrolysis of peptide bonds and deamidation of susceptible residues in related sequences also reduce purity over time. Lyophilised material kept dry at minus twenty degrees Celsius and shielded from light is the most stable form commonly described in laboratory practice.
Material sold for laboratory use varies widely in stated purity and documentation. A certificate of analysis should list the analytical method, the column and detector used, and the observed purity value. Independent verification by an outside laboratory is the practical way to confirm identity when documentation is absent or internally inconsistent. Regulatory status differs by country, and a product legal in one jurisdiction may be unapproved or controlled in another.
Semax 是人工设计的七肽，序列为 Met-Glu-His-Phe-Pro-Gly-Pro，骨架取自促肾上腺皮质激素片段 ACTH(4-10)。它于二十世纪八十年代在苏联的分子遗传学研究机构内合成。设计目标是保留该片段与注意力和记忆相关的活性，同时剔除促皮质激素释放等内分泌作用。此后俄罗斯将其登记为药品并进入临床使用。
当时的短肽研究普遍关注能否穿越血脑屏障、在低剂量下产生中枢效应，Semax 属于这一路线。鼻内给药是其主要使用方式，俄语文献报道的适应症涵盖缺血性卒中、短暂性脑缺血发作、认知功能减退以及视神经病变。这些研究大多发表在当地期刊上，样本规模与终点设置同西方试验惯例存在差异，国际同行对其临床证据的强度看法不一。
各国监管态度分化明显。俄罗斯按处方药管理，部分东欧国家留有使用记录；欧盟与美国未批准其作为药物上市，市面流通品通常标注为研究用化学品。身份差异意味着标示含量、纯度与无菌性缺少统一核查。体育领域还牵涉反兴奋剂名录，跨境携带则受目的地药品法规约束。
== External operations == The Selous Scouts were involved in the Rhodesian military's attacks on insurgents and their bases in neighbouring countries, often known as external operations (or 'externals' for short). These operations became frequent from 1976. The unit's role in external operations included intelligence collection and directly attacking insurgents. In the intelligence gathering role, the Selous Scouts' Reconnaissance Troop conducted one or two man long-range reconnaissance patrols to locate or gather information on insurgent bases in Mozambique and Zambia. During direct attacks the Selous Scouts often impersonated soldiers of the country they were operating in. The Selous Scouts operated in eastern Botswana. This included fighting small actions against insurgents and a raid in which ZAPU leaders were captured in Francistown. The Selous Scouts also used pseudo tactics to collect intelligence in Francistown. Operation Long John was launched on 25 June 1976, against two guerilla bases located in Mozambique. This operation used 'flying column' tactics for the first time, which involved six vehicles manned by the Selous Scouts attacking the bases. Large quantities of munitions were destroyed, but few casualties were inflicted. On 9 August 1976, the Selous Scouts carried out Operation Eland, a raid on a ZANLA and FRELIMO controlled refugee camp at Nyadzonia in Mozambique. The Selous Scouts, who were mostly black and disguised in FRELIMO uniforms, included former Portuguese Army soldiers and a former ZANLA commander.
Glutathione S-transferase theta-2 is an enzyme that in humans is encoded by the GSTT2 gene. Glutathione S-transferase (GSTs) theta 2 (GSTT2) is a member of a superfamily of proteins that catalyze the conjugation of reduced glutathione to a variety of electrophilic and hydrophobic compounds. Human GSTs can be divided into five main classes: Alpha, Mu, Pi, Theta, and Zeta. The theta class members GSTT1 and GSTT2 share 55% amino acid sequence identity and both are thought to have an important role in human carcinogenesis. The theta genes have a similar structure, being composed of five exons with identical exon/intron boundaries.
=== Thrombin-like === These include thrombin, tissue activating plasminogen and plasmin. They have been found to have roles in coagulation and digestion as well as in the pathophysiology of neurodegenerative disorders such as Alzheimer's and Parkinson's induced dementia. Many highly-toxic thrombin-like serine protease isoforms are found in snake venoms.
Sources: en.wikipedia.org
Restoration In nasal reconstruction, the plastic surgeon's ultimate goal is recreating the shadows, the contours, the skin color, and the skin texture that define the patient's "normal nose", as perceived at conversational distance (c. 1.0 metre). Yet, such an aesthetic outcome suggests the application of a more complex surgical approach, which requires that the surgeon balance the patient's required rhinoplasty, with the patient's aesthetic ideal (body image). In the context of surgically reconstructing the patient's physiognomy, the "normal nose" is the three-dimensional (3-D) template for replacing the missing part(s) of a nose (aesthetic nasal subunit, aesthetic nasal segment), which the plastic surgeon re-creates using firm, malleable, modelling materials—such as bone, cartilage, and flaps of skin and of tissue. In repairing a partial nasal defect (wound), such as that of the alar lobule (the dome above the nostrils), the surgeon uses the undamaged, opposite (contralateral) side of the nose as the 3-D model to fabricate the anatomic template for recreating the deformed nasal subunit, by molding the malleable template material directly upon the normal, undamaged nasal anatomy. To effect a total nasal reconstruction, the template might derive from quotidian observations of the "normal nose" and from photographs of the patient before they sustained the nasal damage.
Jennings was also appointed as a pitchman for Wisconsin even outside the specialized burger promotion, in a contract signed on October 1, 2009; in exchange, A&W donated $10,000 to The Greg Jennings Foundation. In January 2013, A&W Restaurants appointed Lexington-based advertising agency Cornett Integrated Marketing as its new agency of record. The contract was renewed in January 2024. In January 2019, ahead of its hundredth anniversary, A&W removed the ampersand from its logo as part of a tongue-in-cheek campaign to bring back the ampersand to the alphabet as its 27th letter. Beginning in October 2020, in order to recoup economic losses from the closure of several of its restaurants, A&W set up a series of quizzes on its website. For Halloween that year, it released a web stunt called The Onion Ring, a parody of The Ring. A&W unveiled a new campaign in 2024, capitalizing on the ampersand of its logo and the tagline Burgers, Floats & Then Some. Packaging was also changed accordingly.
=== Clinical safety === Early clinical trials with DMSO were stopped because of questions about its safety, especially its ability to harm the eye. The most commonly reported side effects include headaches and burning and itching on contact with the skin. Strong allergic reactions have been reported. On September 9, 1965, The Wall Street Journal reported that a manufacturer of the chemical warned that the death of an Irish woman after undergoing DMSO treatment for a sprained wrist may have been due to the treatment, although no autopsy was done, nor was a causal relationship established. Clinical research using DMSO was halted and did not begin again until the National Academy of Sciences (NAS) published findings in favor of DMSO in 1972. In 1978, the US FDA approved DMSO for treating interstitial cystitis. In 1980, the US Congress held hearings on claims that the FDA was slow in approving DMSO for other medical uses. In 2007, the US FDA granted "fast track" designation on clinical studies of DMSO's use in reducing brain tissue swelling following traumatic brain injury. DMSO exposure to developing mouse brains can produce brain degeneration. This neurotoxicity could be detected at doses as low as 0.3 mL/kg, a level exceeded in children exposed to DMSO during bone marrow transplant.
=== Cytochrome electron carriers === Cytochromes are proteins that contain iron. They are found in two very different environments. Some cytochromes are water-soluble carriers that shuttle electrons to and from large, immobile macromolecular structures imbedded in the membrane. The mobile cytochrome electron carrier in mitochondria is cytochrome c. Bacteria use a number of different mobile cytochrome electron carriers. Other cytochromes are found within macromolecules such as Complex III and Complex IV. They also function as electron carriers, but in a very different, intramolecular, solid-state environment. Electrons may enter an electron transport chain at the level of a mobile cytochrome or quinone carrier. For example, electrons from inorganic electron donors (nitrite, ferrous iron, electron transport chain) enter the electron transport chain at the cytochrome level. When electrons enter at a redox level greater than NADH, the electron transport chain must operate in reverse to produce this necessary, higher-energy molecule. It has been observed that inter-protein electron transport between cytochromes c and c1 (complex III) depends on pH and the presence of oxygen, suggesting that protons and superoxide may act as redox mediators in the long-distance electron transport process through the aqueous solution.
Sources: en.wikipedia.org
In these places, the bricks would become a blank canvas for artists, intellectuals and young people to tackle the "Wall" phenomenon. To commemorate the 20th anniversary of the fall of the Berlin Wall, the 3D online virtual world Twinity reconstructed a true-to-scale section of the Wall in virtual Berlin. The MTV Europe Music Awards, on 5 November, had U2 and Tokio Hotel perform songs dedicated to and about the Berlin Wall. U2 performed at the Brandenburg Gate, and Tokio Hotel performed "World Behind My Wall". Palestinians in the town of Kalandia, West Bank, pulled down parts of the Israeli West Bank barrier, in a demonstration marking the 20th anniversary of the fall of the Berlin Wall. The International Spy Museum in Washington D.C., hosted a Trabant car rally where 20 Trabants gathered in recognition of the 20th anniversary of the fall of the Berlin Wall. Rides were raffled every half-hour and a Trabant crashed through a Berlin Wall mock up. The Trabant was the East German people's car that many used to leave DDR after the collapse. The Allied Museum in the Dahlem district of Berlin hosted a number of events to mark the 20th anniversary of the fall of the Berlin Wall. The museum held a Special Exhibition entitled "Wall Patrol – The Western Powers and the Berlin Wall 1961–1990" which focused on the daily patrols deployed by the Western powers to observe the situation along the Berlin Wall and the fortifications on the GDR border. A sheet of "Americans in Berlin" Commemorative Cinderella stamps designed by T.H.E.
The US Treasury declares that it has cut off all Banque Misr's UAE branches from dollar transactions due to its dealings with the Iranian government. August 29 Trump declares that the US reached a deal with Venezuela for controlling 65 billion barrels of its oil reserves. The former White House teleprompter operator Gabriel Perez is ordered by the Commodity Futures Trading Commission to pay $172,000 for using advance access to Trump's speeches to make illegal betting on prediction-market platform Kalshi. A federal court in California rules that Trump cannot deport students who criticize the Israeli war in Gaza. American singer Olivia Rodrigo holds the inaugural charitable Daisy Chain Fields music festival in Irvine, California, U.S., a day after announcing that the festival would donate US$10 million to organizations contributing to women’s rights and reproductive justice. August 30 NASA launches the flagship Nancy Grace Roman Space Telescope aboard a SpaceX Falcon Heavy rocket from the Kennedy Space Center in Florida. Designed to investigate dark energy, dark matter and exoplanets, the observatory has a field of view at least 100 times larger than the Hubble Space Telescope's. U.S. forces state that they targeted two Iranian launchers on Larak Island after IRGC forces were identified preparing to launch rockets carrying sea mines toward the Strait of Hormuz. August 31 Iran claims to have retaliated by attacking U.S. bases in Jordan and U.S. military assets in the United Arab Emirates. Trump promises to respond to the Iranian attack against American soldiers in Jordan.
Tight junctions are very important in embryo development. In the blastula, these cadherin mediated cell interactions are essential to development of epithelium which are most important to paracellular transport, maintenance of cell polarity and the creation of a permeability seal to regulate blastocoel formation. These tight junctions arise after the polarity of epithelial cells is established which sets the foundation for further development and specification. Within the blastula, inner blastomeres are generally non-polar while epithelial cells demonstrate polarity. Mammalian embryos undergo compaction around the 8-cell stage where E-cadherins as well as alpha and beta catenins are expressed. This process makes a ball of embryonic cells which are capable of interacting, rather than a group of diffuse and undifferentiated cells. E-cadherin adhesion defines the apico-basal axis in the developing embryo and turns the embryo from an indistinct ball of cells to a more polarized phenotype which sets the stage for further development into a fully formed blastocyst. Xenopus membrane polarity is established with the first cell cleavage. Amphibian EP-cadherin and XB/U cadherin perform a similar role as E-cadherin in mammals establishing blastomere polarity and solidifying cell-cell interactions which are crucial for further development.
Sources: en.wikipedia.org
It consists mainly of animal experiments and small clinical reports, with much of the clinical material published in Russian-language journals. Large independent trials are scarce. Separating reliable effects from chance findings is consequently difficult.
A fraction of an intranasal dose is thought to reach the central nervous system, and this route is favoured partly for that reason. The proportion is not well characterized. Direct measurement in humans remains difficult with current methods.
Raised BDNF and NGF expression has been reported across several animal studies, which makes the signal fairly consistent. Whether the same change occurs in humans at usable doses is not established. It is best treated as a working hypothesis rather than a confirmed clinical mechanism.
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。