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.
Updated 2025-10-08. Numbers and descriptions here follow the published literature rather than marketing material.
Published research has focused mainly on neurological and cognitive endpoints in animal models, with proposed mechanisms involving brain-derived neurotrophic factor and related signalling pathways. A substantial share of the human data originates from a limited number of research groups, and independent replication in other countries remains sparse. Regulatory status reflects that distribution: the peptide is registered as a medicine in Russia and appears in some neighbouring markets, while elsewhere it is handled as a research chemical without approved therapeutic labelling. Questions about dose-response relationships, long-term effects, and comparability across studies are still open.
Lyophilised powder is normally kept at -20 °C in a desiccated container, with some suppliers recommending -80 °C for long-term archival storage. Repeated freeze-thaw cycles are the most common cause of avoidable loss, so aliquoting before freezing reduces variability between working sessions. Dissolved peptide is far less stable than the dry solid and is usually prepared fresh or held briefly at 4 °C. Aqueous solutions support both hydrolysis of the backbone and oxidation of the N-terminal methionine, and these two routes dominate degradation under ordinary laboratory conditions.
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.
| Property | Value | Notes |
|---|---|---|
| Purity assay | RP-HPLC, UV 214 nm | Typical research grade 95 percent or higher |
| Mass confirmation | ESI-MS or MALDI-TOF | Compared with theoretical value |
| Main degradation route | Methionine oxidation | Sulfoxide formation in solution |
| Powder storage | -20 °C, desiccated | Amber vial, minimal headspace |
| Working solution | Sterile water or saline | Prepare fresh; avoid repeated thawing |
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.
Identity and purity of semax are established with reversed-phase high-performance liquid chromatography coupled to ultraviolet detection, usually at 214 nanometres. Mass spectrometry, most often electrospray ionisation in positive mode, confirms the molecular mass and reveals truncated sequences. Amino acid analysis and peptide mapping after enzymatic digestion provide additional structural confirmation. Laboratories typically report purity as the percentage area of the main peak, a figure that does not capture isomeric or oxidised variants unless the method resolves them.
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.
Regulatory status varies sharply by country. Semax is registered for medical use in Russia, where it appears in formularies as a nasal solution, and it also holds registration in a small number of neighbouring states. It has no approval from the United States Food and Drug Administration or the European Medicines Agency, and it is not a scheduled controlled substance in most jurisdictions. Elsewhere it circulates mainly as laboratory material, so purity documentation comes from suppliers rather than from a national pharmacopoeia.
Semax is a synthetic peptide created in the Soviet Union during the early 1980s by researchers working in Moscow. It was built from the short adrenocorticotropic hormone fragment known as ACTH(4-10), and the chain was then extended with three additional amino acids. The resulting molecule was named semax and entered clinical use in Russia in 1994. It is generally described as a nootropic and neuroprotective agent rather than as a hormone analogue.
The parent fragment ACTH(4-10) carries the sequence Met-Glu-His-Phe-Arg-Trp-Gly. Semax replaces the arginine and tryptophan positions with a proline-glycine-proline tail, giving Met-Glu-His-Phe-Pro-Gly-Pro. That change removes residues associated with adrenal stimulation, so the peptide does not drive cortisol release the way full ACTH does. This distinction shapes how the compound is grouped in the literature, where it sits with neuropeptides and peptide neuromodulators rather than with corticosteroids.
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.
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.
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。
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。
In January 2013, Politburo Standing Committee member Liu Yunshan referred to Xi's speech for the 18th Party National Congress as the "General Secretary Xi Jinping's Series of Important Speeches". In October 2017, the CCP Central Committee announced that Xi's political philosophies were developed into the "Xi Jinping Thought on Socialism with Chinese Characteristics for a New Era". Xi first made mention of the "Thought on Socialism with Chinese Characteristics for a New Era" in his opening day speech delivered to the 19th Party Congress in October 2017. His Politburo Standing Committee colleagues, in their own reviews of Xi's keynote address at the Congress, prepended the name "Xi Jinping" in front of "Thought". On 24 October 2017, at its closing session, the 19th Party Congress approved the incorporation of Xi Jinping Thought into the Constitution of the CCP, while in March 2018, the National People's Congress amended the state constitution to include Xi Jinping Thought.
The system studied – the part of the patient that is the object of the examination (blood plasma, pituitary gland, skin, kidney, whole body) The component – the specific part or process that is of interest in the system studied (glucose, hormone secretion, bacteria, urine excretion) The kind-of-property - (amount-of-substance concentration, secretion rate, number, volume) An SI unit or WHO where relevant – (for measurable properties, i.e. differential or rational [not ordinal] quantities). These statements are ordered in a fixed syntax:
=== C-Linked glycans === Of the three linkages the least common and least understood are C-linked glycans. The C-linkage refers to the covalent attachment of mannose to a tryptophan residue. An example of a C-linked glycan is α-mannosyl tryptophan.
An additional study published in 2020 by Woodward and colleagues, for the journal Science Advances indicates that during their growth from juvenile to adult, Tyrannosaurus was capable of slowing down its growth to counter environmental factors such as lack of food. Based on BMRP 2002.4.1 and BMRP 2006.4.4 between 13 and 15 years old housed at the Burpee Museum in Illinois then referred to as juvenile Tyrannosaurus specimens, the authors suggested that the rate of maturation for Tyrannosaurus was dependent on resource abundance. This study also indicates that in such changing environments, Tyrannosaurus was particularly well-suited to an environment that shifted yearly in regards to resource abundance, hinting that other midsize predators might have had difficulty surviving in such harsh conditions and explaining the niche partitioning between juvenile and adult tyrannosaurs. The study further suggested that Tyrannosaurus and Nanotyrannus are synonymous, due to analysis of the growth rings in the bones of the two specimens studied. In January 2026, Woodward, Myhrvold and Horner performed a comprehensive histological analysis of 17 tyrannosaur specimens, and argued that Tyrannosaurus likely experienced a more gradual annual growth rate slope than indicated by earlier studies and evidence of a protracted subadult stage, reaching asymptotic size at around 35–40 years of age. The upper limit of the annual growth rate estimate is approximately 43–53 years.
As a genetic disorder, the mainstay of twenty-first-century prevention of osteogenesis imperfecta is based on preventing affected individuals from being born in the first place. Genetic counseling can help patients and their families determine what types of screening, if any, are right for their situation. Patients can consider preimplantation genetic diagnosis after in vitro fertilization to select fertilized embryos that are not affected. Common mutations which cause OI may be caught by exome sequencing and whole genome sequencing. If a pregnancy is already in progress, the procedure of amniocentesis may be undergone to see if the fetus is affected. If affected, it is up to the family to consider whether or not they want to terminate the pregnancy and try again—raising questions of medical ethics and a woman's right to choose. Without intervention, patients with the most common mutations causing osteogenesis imperfecta have a 50% chance per gestation of passing on the disorder, as these mutations are inherited in an autosomal dominant pattern of Mendelian inheritance. Those with the rare autosomal recessive forms of OI have a 25% chance of passing on the disorder. Genetic testing of the affected members of the family can be used to determine which inheritance pattern applies. As OI type I may be difficult to detect in a newborn child, the cord blood of the child can be tested to determine if it has been passed on, if the family has already rejected the more invasive genetic screening methods.
Sources: en.wikipedia.org
=== Vitamin D influence on immune response === Vitamin D is known as an immune regulator that assists in the adaptive and innate immune response. A deficiency in vitamin D, from hereditary or environmental influence, can lead to a more inefficient and weaker immune response and seen as a contributing factor to the development of autoimmune diseases. With vitamin D present, vitamin D response elements are encoded and expressed via pattern recognition receptors responses and the genes associated with those responses. The specific DNA target sequence expressed is known as 1,25-(OH)2D3. The expression of 1,25-(OH)2D3 can be induced by macrophages, dendritic cells, T-cells, and B-cells. In the presence of 1,25-(OH)2D3, the immune system's production of inflammatory cytokines are suppressed and more tolerogenic regulatory T-cells are expressed. This is due to vitamin D's influence on cell maturation, specifically T-cells, and their phenotype expression. Lack of 1,25-(OH)2D3 expression can lead to less tolerant regulatory T-cells, larger presentation of antigens to less tolerant T-cells, and increased inflammatory response.
== In plants == Plant cells are tessellated to form tissues. The cell wall is the relatively rigid structure surrounding the plant cell. The cell wall provides lateral strength to resist osmotic turgor pressure, but it is flexible enough to allow cell growth when needed; it also serves as a medium for intercellular communication. The cell wall comprises multiple laminate layers of cellulose microfibrils embedded in a matrix of glycoproteins, including hemicellulose, pectin, and extensin. The components of the glycoprotein matrix help cell walls of adjacent plant cells to bind to each other. The selective permeability of the cell wall is chiefly governed by pectins in the glycoprotein matrix. Plasmodesmata (singular: plasmodesma) are pores that traverse the cell walls of adjacent plant cells. These channels are tightly regulated and selectively allow molecules of specific sizes to pass between cells.
The first use of radioluminescence was in luminous paint containing radium, a natural radioisotope. Beginning in 1908, luminous paint containing a mixture of radium and copper-doped zinc sulfide was used to paint watch faces and instrument dials, giving a greenish glow. Phosphors containing copper-doped zinc sulfide (ZnS:Cu) yield blue-green light; copper and manganese-doped zinc sulfide (ZnS:Cu,Mn), yielding yellow-orange light are also used. Radium-based luminescent paint is no longer used due to the radiation hazard posed to persons manufacturing the dials. These phosphors are not suitable for use in layers thicker than 25 mg/cm2, as the self-absorption of the light then becomes a problem. Zinc sulfide undergoes degradation of its crystal lattice structure, leading to gradual loss of brightness significantly faster than the depletion of radium. ZnS:Ag coated spinthariscope screens were used by Ernest Rutherford in his experiments discovering the atomic nucleus. Radium was used in luminous paint until the 1960s, when it was replaced with the other radioisotopes mentioned above due to health concerns. In addition to alpha and beta particles, radium emits penetrating gamma rays, which can pass through the metal and glass of a watch dial, and skin. A typical older radium wristwatch dial has a radioactivity of 3–10 kBq and could expose its wearer to an annual dose of 24 millisieverts if worn continuously. Another health hazard is its decay product, the radioactive gas radon, which constitutes a significant risk even at extremely low concentrations when inhaled.
On 7 April, The Rafi'-Nia synagogue in central Tehran was destroyed in an airstrike. Israel said that the building was destroyed due to collateral damage and that it was never meant to be the direct target of the airstrike. The same day, US forces began strikes on Kharg Island. In response, Iran said its restraint in targeting oil infrastructure in the region would no longer apply. Trump posted to Truth Social that "a whole civilization will die tonight, never to be brought back again", causing international concern that Trump would use nuclear weapons. The Secretary General of Amnesty International said that Trump's statement "may constitute a threat to commit genocide". Multiple right-wing commentators and many Democrats condemned the post, and some called for him to be removed through the 25th Amendment. The White House denied considering using nuclear weapons and later said that "only the president knows" what he would do on Iran. A leaked US intelligence report concluded that Iran retained 70% of missiles and launchers at this point, despite Trump claims regarding "destruction" of Iran's military. In the United Nations Security Council, China and Russia vetoed a Bahraini-led draft resolution calling on member states to coordinate efforts to protect commercial shipping in the Strait of Hormuz, with Chinese representative Fu Cong stating that adopting such a draft when the U.S. was threatening the survival of a civilization would send the wrong message.
(2026) study the composition of the Quaternary small mammal assemblage from the Araras Ravine at the Lajedo de Soledade site (Rio Grande do Norte, Brazil), providing evidence of similarities with extant faunas from open environments in the Caatinga and Cerrado. A study on the late Pleistocene/early Holocene fauna from the Pikimachay Cave (Peru) is published by Yataco et al. (2026), who interpret the studied site as likely to be a giant ground sloth burrow that was also used by carnivores and/or humans. Hullot et al. (2026) propose a standardized methodological framework for the study of enamel histology in fossil taxa, and apply it to the study of enamel histology and growth of molars of toxodont notoungulates Pleurostylodon modicus, Eurygenium pacegnum, Adinotherium ovinum and Nesodon imbricatus. Von Koenigswald (2026) reviews the morphological diversity of incisors and canines in extant and fossil mammals. Wilson et al. (2026) compare the wear of bilophodont teeth in xenungulates, pyrotheres, fossil and modern tapirs and in extant marsupials, and interpret their findings as suggestive of browsing feeding behaviors of xenungulates and fossil tapirs, as well as of variable diets of different members of Pyrotheria. Evidence of preservation of amino acids in tooth enamel of fossil proboscideans, equids and rhinocerotids dating back as far as 48 million years is presented by Gatti et al. (2026). Herrando-Pérez et al.
Sources: en.wikipedia.org
Reversed-phase HPLC gives the main purity figure, most often with UV detection near 214 nanometres. Mass spectrometry then confirms the molecular mass. Together the two methods distinguish a correct sequence from a closely related impurity.
The main chemical risks are methionine oxidation and backbone hydrolysis in solution. Moisture and repeated temperature cycling accelerate both processes. Dry powder held cold and desiccated is considerably more stable than any reconstituted preparation.
It holds a medicine registration in Russia, where it has been used clinically for decades. In most other countries it is treated as a research chemical. That split explains the uneven distribution of clinical literature.
It is a synthetic peptide of seven amino acids. Its backbone corresponds to a fragment of adrenocorticotropic hormone extended at the carboxyl end. The material is distributed as a lyophilized solid for laboratory use.