鼻内给药 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.
Last reviewed on 2026-02-25. Where a claim depends on a specific study, the study is described rather than over-claimed.
The C-terminal Pro-Gly-Pro extension is not incidental. Proline-rich tails are known to resist several common peptidases, and the published literature attributes the longer half-life of Semax, relative to unmodified ACTH fragments, to this feature. The modification also removes the melanocyte-stimulating and corticosteroidogenic activity that characterizes longer ACTH-derived sequences. Because the molecule is small and hydrophilic, it is typically formulated as an aqueous solution for intranasal or parenteral delivery. Acetylation or amidation at the termini appears in closely related research peptides and shifts the mass by a fixed increment.
Reported pharmacological work centers on neurotrophic signaling, including changes in BDNF and NGF expression in hippocampal tissue in animal models. Human data come largely from studies conducted in Russia, and how well those results generalize to other populations remains an open question. Regulatory status differs sharply by jurisdiction: Semax is a registered prescription medicine in Russia, while it holds no approved marketing status in the United States or the European Union. Outside such jurisdictions it is generally handled as a research chemical, which affects both documentation and quality expectations.
Semax is a synthetic heptapeptide whose sequence is Met-Glu-His-Phe-Pro-Gly-Pro. It was developed as a fragment analog of adrenocorticotropic hormone, modeled specifically on the ACTH(4-10) region. The first four residues reproduce that fragment, while a Pro-Gly-Pro tripeptide is appended at the C-terminus. Work on the compound originated in Russia, where it entered clinical use as an intranasal preparation. Its sequence places it among short regulatory peptides studied for effects on the central nervous system rather than on the adrenal axis.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It is described in the literature as an analogue of the ACTH(4–10) fragment, a short N-terminal portion of adrenocorticotropic hormone that retains some neurotropic activity without the full hormonal effects of the parent peptide. The molecule carries a methionine residue at the N-terminus and two proline residues near the C-terminus, features that shape both its interactions with receptor systems and its chemical stability. The free peptide corresponds to the formula C37H51N9O10S and a molecular mass near 813.9 Da.
The compound was developed in the 1980s at the Institute of Molecular Genetics in Moscow, where it emerged from research on short ACTH fragments and their effects on the central nervous system. Russian pharmaceutical listings describe it as a nootropic and neuroprotective agent, most often formulated as nasal drops. It is not a marketed medicine in the United States or the European Union, and no pharmacopoeial monograph covers it. Consequently, most published clinical experience with the substance originates from a small number of research centres, mainly in Russia and neighbouring countries.
Pharmacological accounts link semax to melanocortin signalling and to modulation of neurotrophic factor expression, particularly brain-derived neurotrophic factor and nerve growth factor. Much of this evidence comes from rodent studies using intranasal delivery, a route chosen because it allows peptides to reach the central nervous system with limited systemic exposure. Whether the same mechanisms operate in humans at comparable magnitude remains an open question. The precise receptor or receptors responsible for the reported behavioural and neuroprotective effects have not been conclusively identified.
| Property | Value | Notes |
|---|---|---|
| Molecular weight | ~813.9 Da (free heptapeptide) | N-acetylated form is about 42 Da heavier |
| Residue count | 7 (heptapeptide) | Four residues from ACTH(4-10), three added |
| Appearance | White to off-white powder | Usually supplied lyophilized |
| Solubility class | Freely soluble in water | Also dissolves in DMSO and polar organic solvents |
| Related parent fragment | ACTH(4-10) | Parent motif is Met-Glu-His-Phe |
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.
Scientific literature on semax is unevenly distributed. A substantial share of published work originates from a small number of laboratories in Russia, while independent replication elsewhere is limited. Human data consist mostly of small trials with short follow-up, and several reported outcomes rely on subjective rating scales. Questions about how much intact peptide reaches the central nervous system after nasal administration, and how long it persists there, are still unresolved. The compound is best described as an active research subject rather than a settled pharmacological agent.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It was derived from the ACTH(4-10) fragment, a short segment of adrenocorticotropic hormone that lacks the hormonal activity associated with the full-length peptide. Researchers at the Institute of Molecular Genetics in Moscow developed the compound during the 1980s. It has been registered as a pharmaceutical product in Russia and several neighbouring countries, where it is supplied as a nasal solution, and it is also sold internationally as a research chemical.
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。
==== COVID-19 ==== Dogs have been trained to sniff SARS CoV-2-related VOCs since the outbreak of COVID-19 pandemic. Their overall success rates of detection were similar to or higher than reverse transcription polymerase chain reaction (RT-PCR) and antigen testing procedures. Grandjean et al. trained the dogs to sit in front of samples from COVID-19 positive patients. The success rate of distinguishing the sweat odor of individuals with COVID-19 from individuals without COVID-19 was between 83% and 100%. In principle, the dogs could be used to screen individuals with various stages of COVID-19 infections (including asymptotic, presymptomatic individuals with mild to severe symptoms) in different settings such as schools, transportation centers like airports, hospitals, and public gatherings. An advantage of using trained dogs compared to primates or cats to detect COVID-19 is that dogs are animal species with a low risk of binding between ACE2 receptor and SARS CoV-2, making them less likely to be transmitters. To further minimize the risk of transmission to dogs, sniffing sweat (which has low transmission property) is deemed the ideal mechanism for dogs to detect COVID-19. Other advantages of using dogs for screening COVID-19 over the current RT-PCR method are lower cost, decreased intrusiveness to the subjects, and no delay in reporting the results.
=== Marketing === The marketing of the Claritin brand is important in the history of direct-to-consumer advertising of drugs. The first television commercial for a prescription drug was broadcast in the United States in 1983, by Boots. It caused controversy. The federal Food and Drug Administration responded with strong regulations requiring disclosure of side effects and other information. These rules made pharmaceutical manufacturers balk at spending money on ads that had to highlight negative aspects. In the mid-1990s, the marketing team for Claritin at Schering-Plough found a way around these rules. They created brand awareness commercials that never actually said what the drug was for, but instead showed sunny images, and the voiceover said such things as "At last, a clear day is here" and "It's time for Claritin" and repeatedly told viewers "Ask your doctor [about Claritin]." The first ads made people aware of the brand and increased prescriptions, which led Schering-Plough and others to aggressively pursue the advertising strategy. In 1998, a 12-page one-shot comic based on the Batman: The Animated Series was given away to advertise Claritin. The book, written by PRIEST, penciled by Joe Staton, and inked by Mike DeCarlo, sees Tim Drake unable to perform his crime-fighting duties because hay fever and antihistamines make him drowsy. After being given a prescription for Claritin, he saved Batman from Poison Ivy.
1 June – A study shows the clonal diversity of stem cells that produce blood cells gets drastically reduced around age 70 to a faster-growing few, substantiating a novel theory of ageing which could enable healthy aging. 2 June – First success of a clinical trial for a 3D bioprinted transplant, an external ear to treat microtia, that is made from the patient's own cells is reported. 3 June – The NOAA reports that the global concentration of carbon dioxide in Earth's atmosphere is now 50% greater than in pre-industrial times, and is likely at a level last seen 4.1 to 4.5 million years ago, at 421 parts per million (ppm). 5 June – Progress in the treatment of cancer:A very small trial shows complete remission of a type of colorectal cancer without surgery and radiation in all 12 patients. On the same day, results of a trial show that trastuzumab deruxtecan therapy for HER2-low metastatic breast cancer exceeded results from chemotherapy. The synthesis of ERX-41, a novel compound that has shown promise in eliminating cancer cells, is reported (2 June). Researchers describe a new light-activated 'photoimmunotherapy' for brain cancer in vitro. They believe it could join surgery, chemotherapy, radiotherapy and immunotherapy as a fifth major form of cancer treatment (16 June). 6 June – Cats are added to the list of animals that can get SARS-CoV-2 and spread it back to humans, albeit the transmission is considered uncommon and not to be a source of variants of concern since the August 2021 detection.
P2X receptors are ligand-gated ion channels, whereas the P1 and P2Y receptors are G protein-coupled receptors. These ligand-gated ion channels are nonselective cation channels responsible for mediating excitatory postsynaptic responses, similar to nicotinic and ionotropic glutamate receptors. P2X receptors are distinct from the rest of the widely known ligand-gated ion channels, as the genetic encoding of these particular channels indicates the presence of only two transmembrane domains within the channels. These receptors are greatly distributed in neurons and glial cells throughout the central and peripheral nervous systems. P2X receptors mediate a large variety of responses including fast transmission at central synapses, contraction of smooth muscle cells, platelet aggregation, macrophage activation, and apoptosis. Moreover, these receptors have been implicated in integrating functional activity between neurons, glial, and vascular cells in the central nervous system, thereby mediating the effects of neural activity during development, neurodegeneration, inflammation, and cancer. The physiological modulator Zn2+ allosterically enhances ATP-induced inward cation currents in the P2X4 receptor by binding to cysteine 132 and cystine 149 residues on the extracellular domain of the P2X4 protein.
2024 Bushey killings: Police announce that a manhunt is underway for Kyle Clifford, a 26-year-old man suspected of murdering three women in Bushey, Hertfordshire, using a crossbow. The public is warned not to approach him. Police identify the three women as 61-year-old Carol Hunt, wife of BBC Racing commentator John Hunt, and two of their daughters, Hannah Hunt, 28 and Louise Hunt, 25. Clifford is found and arrested in Enfield by the early evening. Euro 2024: England win 2–1 against the Netherlands, with Ollie Watkins scoring a 90th minute winning goal, taking them through to the final against Spain. 11 July Data shows the UK economy grew by 0.4% in May, expanding more than had been expected. A manhunt is launched after two suitcases containing human remains are found at the Clifton Suspension Bridge in Bristol. 12 July Four migrants die and 63 are rescued after their small boat capsizes in an attempt to cross the English Channel. According to International Organization for Migration this brings the total deaths resulting from such crossing attempts to more than 20 so far for 2024. Royal Mail unveil their new logo, based on the Tudor Crown used in the royal cypher of King Charles III, which replaces the St Edward's Crown used by Queen Elizabeth II. The first post box with the new logo is in Cambourne, Cambridgeshire. Following his guilty verdict on 4 July, Gavin Plumb is sentenced to life imprisonment, with a minimum term of 15 years.
Sources: en.wikipedia.org
Stratum corneum Stratum lucidum (only in palms and soles) Stratum granulosum Stratum spinosum Stratum basale (also called the stratum germinativum) Keratinocytes in the stratum basale proliferate through mitosis and the daughter cells move up the strata changing shape and composition as they undergo multiple stages of cell differentiation to eventually become anucleated. During that process, keratinocytes will become highly organized, forming cellular junctions (desmosomes) between each other and secreting keratin proteins and lipids which contribute to the formation of an extracellular matrix and provide mechanical strength to the skin. Keratinocytes from the stratum corneum are eventually shed from the surface (desquamation). The epidermis contains no blood vessels, and cells in the deepest layers are nourished by diffusion from blood capillaries extending to the upper layers of the dermis.
The history of chemistry spans a period from the ancient past to the present. Since several millennia BC, civilizations were using technologies that would eventually form the basis of the various branches of chemistry. Examples include extracting metals from ores, making pottery and glazes, fermenting beer and wine, extracting chemicals from plants for medicine and perfume, rendering fat into soap, making glass, and making alloys like bronze. Chemistry was preceded by its protoscience, alchemy, which operated a non-scientific approach to understanding the constituents of matter and their interactions. Despite being unsuccessful in explaining the nature of matter and its transformations, alchemists set the stage for modern chemistry by performing experiments and recording the results. Robert Boyle, although skeptical of elements and convinced of alchemy, played a key part in elevating the "sacred art" as an independent, fundamental and philosophical discipline in his work The Sceptical Chymist (1661). While both alchemy and chemistry are concerned with matter and its transformations, the crucial difference was given by the scientific method that chemists employed in their work. Chemistry, as a body of knowledge distinct from alchemy, became an established science with the work of Antoine Lavoisier, who developed a law of conservation of mass that demanded careful measurement and quantitative observations of chemical phenomena. The history of chemistry afterwards is intertwined with the history of thermodynamics, especially through the work of Willard Gibbs.
== Structure == Alpha 2-antiplasmin (α2AP) is a member of the serine protease inhibitor (serpin) superfamily and is structurally characterized by a central serpin domain flanked by unique N- and C-terminal extensions. The mature human α2AP protein consists of 452 amino acids, with a 12-residue N-terminus, a central serpin domain, and a C-terminal tail of approximately 55 residues. The reactive center loop, which is crucial for its inhibitory function, protrudes from the central serpin domain and contains the Arg364-Met365 peptide bond that is specifically targeted and cleaved by plasmin. There are two main circulating forms: Met-α2AP, which has methionine at the N-terminus, and Asn-α2AP, which is N-terminally shortened and starts with asparagine; the latter form constitutes about 70% of plasma α2AP and is more efficiently cross-linked to fibrin. The C-terminal region, rich in lysine residues, mediates the initial non-covalent binding to plasmin, facilitating the formation of a stable 1:1 stoichiometric complex. This structural arrangement allows α2AP to efficiently interact with plasmin and be incorporated into fibrin clots via cross-linking by factor XIIIa.
== Methods == Forensic chemists rely on a multitude of instruments to identify unknown substances found at a scene. Different methods can be used to determine the identity of the same substance, and it is up to the examiner to determine which method will produce the best results. Factors that forensic chemists might consider when performing an examination are the length of time a specific instrument will take to examine a substance and the destructive nature of that instrument. They prefer using nondestructive methods first, to preserve the evidence for further examination. Nondestructive techniques can also be used to narrow down the possibilities, making it more likely that the correct method will be used the first time when a destructive method is used.
Sources: en.wikipedia.org
==== Political disagreements with Donald Trump ==== Newsom and Donald Trump have had a prolonged dispute over governance in California and federal policy. Trump has repeatedly criticized Newsom's handling of wildfires, immigration policies, and the general administration of the state, often using derogatory language. In response, Newsom has made sharply critical statements on social media, including personal insults aimed at Trump in 2025 and 2026.
== Proteolysis and diseases == Abnormal proteolytic activity is associated with many diseases. In pancreatitis, leakage of proteases and their premature activation in the pancreas results in the self-digestion of the pancreas. People with diabetes mellitus may have increased lysosomal activity and the degradation of some proteins can increase significantly. Chronic inflammatory diseases such as rheumatoid arthritis may involve the release of lysosomal enzymes into extracellular space that break down surrounding tissues. Abnormal proteolysis may result in age-related neurological diseases such as Alzheimer's disease due to the generation and ineffective removal of peptides that aggregate in cells. Proteases may be regulated by antiproteases or protease inhibitors, and imbalance between proteases and antiproteases can result in diseases, for example, in the destruction of lung tissues in emphysema brought on by smoking tobacco. Smoking is thought to increase the neutrophils and macrophages in the lung which release excessive amount of proteolytic enzymes such as elastase, such that they can no longer be inhibited by serpins such as α1-antitrypsin, thereby resulting in the breaking down of connective tissues in the lung. Other proteases and their inhibitors may also be involved in this disease, for example matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs). Other diseases linked to aberrant proteolysis include muscular dystrophy, degenerative skin disorders, respiratory and gastrointestinal diseases, and malignancy.
•NO + O3 → •NO2 + O2 + hν The activated NO2[◊] luminesces broadband visible to infrared light as it reverts to a lower energy state. A photomultiplier and associated electronics count the photons that are proportional to the amount of nitric oxide (NO) present. To determine the amount of nitrogen dioxide, NO2, in a sample (containing no NO), it must first be converted to NO by passing the sample through a converter before the above ozone activation reaction is applied. The ozone reaction produces a photon count proportional to NO that is proportional to NO2 before it was converted to NO. In the case of a mixed sample that contains both NO and NO2, the above reaction yields the amount of NO and NO2 combined in the air sample, assuming that the sample is passed through the converter. If the mixed sample is not passed through the converter, the ozone reaction produces activated NO2[◊] only in proportion to the NO in the sample. The NO2 in the sample is not activated by the ozone reaction. Though unactivated NO2 is present with the activated NO2[◊], photons are emitted only by the activated species that is proportional to original NO. The final step is to subtract NO from (NO + NO2) to yield NO2
== Food industry == In the food industry, aminopeptidases from Aspergillus oryzae and Aspergillus sojae are utilized for debittering protein hydrolysates, including those used in soy sauce and miso production. These enzymes help remove bitter-tasting peptides, enhancing the flavor and palatability of these products. Aminopeptidases also play a crucial role in cheese ripening by participating in the proteolysis of milk proteins. This enzymatic action contributes significantly to the development of the cheese's flavor and texture, making aminopeptidases essential in the cheese-making process. When aminopeptidases are used in food processing, it is crucial to ensure that they are food-grade and safe for consumption. Aminopeptidases from A. oryzae and A. sojae, for example, have been extensively studied and are considered safe for use in food applications. It is important to handle these enzymes under conditions that prevent contamination and degradation, which could affect both the safety and quality of the food products. Aminopeptidases require specific storage conditions to maintain their stability and enzymatic activity. For instance, human aminopeptidase A is stable at a pH range of 7.0–8.5 and can be stored at −20 °C for several months without significant loss of activity. Similarly, a halotolerant intracellular protease from Bacillus subtilis strain FP-133, which exhibits aminopeptidase activity, retains full activity after being stored in 7.5% (w/v) NaCl at 4 °C for 24 hours.
He named this the "asteroid hypothesis" as an astronomical analogy: just as there is an asteroid belt instead of a single planet between Mars and Jupiter, so the place below yttrium was thought to be occupied by all the lanthanides instead of just one element.
Sources: en.wikipedia.org
The sequence is Met-Glu-His-Phe-Pro-Gly-Pro, a seven-residue peptide. The first four residues correspond to the ACTH(4-10) fragment, and Pro-Gly-Pro is added at the C-terminus. N-acetylated versions also appear in the literature and differ in mass.
Semax is a synthetic analog of the ACTH(4-10) fragment rather than a copy of the full hormone. Truncation plus the added tail removes the steroidogenic portion of ACTH. That distinction explains why it is studied for nervous-system effects instead of adrenal stimulation.
It is registered as a prescription product in Russia and has been used there clinically, chiefly by the intranasal route. No approval exists in the United States or the European Union. Availability elsewhere typically falls under research-chemical distribution, with varying purity documentation.
It is described as a synthetic analogue of the ACTH(4–10) fragment, a short segment of adrenocorticotropic hormone. Its sequence differs from that fragment and includes two proline residues, which influence stability and behaviour in solution.