The short version of intranasal route fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-06-06. Anything still debated is marked as such rather than presented as settled.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Its design combines the ACTH(4-7) core fragment with a C-terminal Pro-Gly-Pro extension, a modification intended to improve stability and prolong activity. The molecule is hydrophilic, carries no lipid chains or glycosylation, and has a theoretical mass just over 810 daltons in its free form. All seven residues are proteinogenic amino acids, so no non-natural building blocks appear in the backbone. A free N-terminal methionine and C-terminal proline define the unmodified parent peptide.
The compound was developed during the 1980s at the Institute of Molecular Genetics in Moscow as part of research on fragments of adrenocorticotropic hormone. Early work examined short ACTH-derived sequences that retained neurotrophic effects while lacking the endocrine activity of the full hormone. Semax entered clinical use in Russia during the 1990s, where it received registration for several neurological indications. Outside that region it remained primarily a laboratory research material rather than an approved therapeutic. English-language literature on it grew more slowly and frequently cited the original Russian studies.
Development is attributed to researchers at the Institute of Molecular Genetics in Moscow during the early 1980s, building on earlier Soviet work with ACTH fragments. Russian regulatory approval followed for intranasal use, and the compound has remained commercially available there for decades. Most published human data originate from Russian and, later, some Eastern European clinical reports, which are not always accessible in English translation. Outside that region the material is generally handled as a research chemical rather than a licensed medicine.
Regulatory status differs sharply between jurisdictions. In Russia the peptide is registered as a prescription nasal preparation, while agencies such as the United States Food and Drug Administration have not approved it for any indication. Products sold elsewhere are typically labeled for laboratory research only, and such labels shift responsibility for safe handling to the purchaser. Because the same name covers pharmaceutical-grade nasal drops and bulk research powder, identity and purity documentation becomes the main practical concern when comparing sources.
Semax is a synthetic seven-amino-acid peptide whose sequence extends the ACTH(4-10) fragment with a C-terminal proline-glycine-proline tripeptide. The commonly cited sequence is Met-Glu-His-Phe-Pro-Gly-Pro, giving a molecular formula near C37H51N9O10S and a molecular weight close to 813.9 g/mol. It belongs to the broader class of synthetic ACTH fragments studied for central nervous system effects rather than for adrenal steroid stimulation. In practice the material appears as a lyophilized white powder for laboratory work or as a dilute saline solution in clinical settings.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide | ACTH(4-7) analogue |
| Sequence | Met-Glu-His-Phe-Pro-Gly-Pro | Free N terminus, unmodified side chains |
| Molecular weight | 813.9 Da | Free base; salt forms differ |
| Appearance | White to off-white powder | Lyophilised solid |
| Solubility | Freely soluble in water | Hydrophilic; polar solvents preferred |
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。
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。
== Annual Conference == Every year the Association of Biomolecular Resource Facilities annual conference is held during the spring in a varying North American city. This international conference is used to expose members to new and emerging biotechnology through lectures, roundtables, Research Group presentations, poster sessions, workshops and technical exhibits.
However, the organism makes antibodies against this viral protein, and those antibodies also kill the human ACTH hormone, which leads to the suppression of adrenal gland function. Such adrenal suppression is a way for a virus to evade immune detection and elimination. This viral strategy can have severe consequences for the host (human that is infected by the virus), as cortisol is essential for regulating various physiological processes, such as metabolism, blood pressure, inflammation, and immune response. A lack of cortisol can result in a condition called adrenal insufficiency, which can cause symptoms such as fatigue, weight loss, low blood pressure, nausea, vomiting, and abdominal pain. Adrenal insufficiency can also impair the ability of the host to cope with stress and infections, as cortisol helps to mobilize energy sources, increase heart rate, and downregulate non-essential metabolic processes during stress. Therefore, by suppressing cortisol production, some viruses can escape the immune system and weaken the host's overall health and resilience.
=== Tertiary dentin (including reparative dentin and reactionary dentin) – pathologic === Tertiary dentin is dentin formed as a reaction to external stimulation such as cavities and wear. It is of two types, either reactionary, where dentin is formed from a pre-existing odontoblast, or reparative, where newly differentiated odontoblast-like cells are formed due to the death of the original odontoblasts, from a pulpal progenitor cell. Tertiary dentin is only formed by an odontoblast directly affected by a stimulus; therefore, the architecture and structure depend on the intensity and duration of the stimulus, e.g., if the stimulus is a carious lesion, there is extensive destruction of dentin and damage to the pulp, due to the differentiation of bacterial metabolites and toxins. Thus, tertiary dentin is deposited rapidly, with a sparse and irregular tubular pattern and some cellular inclusions; in this case, it is referred to as "osteodentin". Osteodentin is seen in Vit.A deficiency during development. However, if the stimulus is less active, it is laid down less rapidly with a more regular tubular pattern and hardly any cellular inclusions. The speed at which tertiary dentin forms also varies substantially among primate species.
=== Prescription trends === In 2010, over 24.4 million prescriptions for generic fluoxetine were filled in the United States, making it the third-most prescribed antidepressant after sertraline and citalopram. In 2011, 6 million prescriptions for fluoxetine were filled in the United Kingdom. Between 1998 and 2017, along with amitriptyline, it was the most commonly prescribed first antidepressant for adolescents aged 12–17 years in England.
Sources: en.wikipedia.org
On 5 October 2018, Singapore carried out three executions of drug traffickers - Zainudin bin Mohamed, Abdul Wahid Bin Ismail, and Mohsen Bin Na’im, it led to the Asian Forum for Human Rights and Development (FORUM-ASIA) and 28 civil society organizations in Asia showing condemnation over the triple hangings, and these groups the death sentence was a grave violation of the right to life, which was "the most fundamental and essential human right for other rights to be realized". They also argued that the executions of Zainudin, Abdul Wahid and Mohsen did not serve any purpose for the island-state and its citizens in terms of fulfilling the ends of justice. In March 2022, when Singapore dismissed the final appeal of Malaysian death row prisoner Nagaenthran K. Dharmalingam and later authorized the execution of Singaporean drug convict Abdul Kahar Othman, which was its first execution during the COVID-19 pandemic, there were 400 Singaporeans, including rights activists Jolovan Wham, Kirsten Han and Kokila Annamalai, who took part in a protest against the government's use of the death penalty at Hong Lim Park. With regards to Abdul Kahar's execution, the European Union (EU) condemned it and stated that capital punishment is a cruel and inhumane punishment, which not only failed to deter crime but also defied both humanity's dignity and integrity. Two days prior to Nagaenthran's execution (which took place on 27 April 2022), a candlelight vigil was held on his behalf.
Cytogenetics is essentially a branch of genetics, but is also a part of cell biology/cytology (a subdivision of human anatomy), that is concerned with how the chromosomes relate to cell behaviour, particularly to their behaviour during mitosis and meiosis. Techniques used include karyotyping, analysis of G-banded chromosomes, other cytogenetic banding techniques, as well as molecular cytogenetics such as fluorescence in situ hybridization (FISH) and comparative genomic hybridization (CGH).
=== Techniques === Single-cell transcriptomics uses sequencing techniques similar to single-cell genomics or direct detection using fluorescence in situ hybridization. The first step in quantifying the transcriptome is to convert RNA to cDNA using reverse transcriptase so that the contents of the cell can be sequenced using NGS methods as was done in genomics. Once converted, there is not enough cDNA to be sequenced so the same DNA amplification techniques discussed in single-cell genomics are applied to the cDNA to make sequencing possible. Alternatively, fluorescent compounds attached to RNA hybridization probes are used to identify specific sequences and sequential application of different RNA probes will build up a comprehensive transcriptome.
== History == 2,5-DMA was first described in the scientific literature by F. Benington and colleagues by at least 1968. Subsequently, it was described in greater detail by Alexander Shulgin in his 1991 book PiHKAL (Phenethylamines I Have Known and Loved).
=== Quantitative sudomotor axon reflex test === The quantitative sudomotor axon reflex test (QSART) was developed in 1983 by Phillip Low as a quantitative method for the identification of localized postganglionic sudomotor dysfunction. Three-compartment sweat capsules are placed on the forearm, proximal and distal leg, as well as the dorsum of the foot. The outer compartment of the capsule is filled with a 10% acetylcholine solution, while nitrogen gas is released steadily onto the skin within the inner compartment. The middle compartment acts as a buffer between the inner and outer compartments to prevent direct stimulation of sweat glands or leakage of the acetylcholine solution. The outflow humidity of the nitrogen gas after passing across the skin is measured by a hygrometer. Once a stable baseline of outflow humidity is reached, iontophoresis of the acetylcholine fluid is initiated by using a 2mA electric current to deliver the acetylcholine into the dermal skin layers. The acetylcholine binds to sweat glands (direct sweat response), and nicotinic and muscarinic receptors on the sudomotor nerve terminals, which transmit the action potential antidromically to axon branch points and then orthodromically to adjacent sudomotor nerves and glands (indirect sweat response). Sweat production is measured as the change in relative humidity over time. The temporal resolution, magnitude, and onset latency of the sweat response are digitally recorded and analyzed using specialized software. QSART is sensitive and specific for detecting postganglionic small fiber dysfunction.
Sources: en.wikipedia.org
In December 2015, a norovirus outbreak at a Chipotle restaurant near Boston College sickened approximately 140 people, many of them students. The Boston Public Health Commission traced the outbreak to a sick employee who had been allowed to work. In response to the 2015 outbreaks, Chipotle closed all locations on February 8, 2016, for an all-staff food safety meeting and hired a new head of food safety who instituted enhanced protocols including more frequent handwashing, produce sanitation procedures, and Pascalization to pre-treat ingredients.
In 1867 the Swiss botanist Simon Schwendener upended orthodox lichen theory with a daring new hypothesis. In a lecture in September he argued that a lichen is a duo—a fungus that houses an alga—rather than a lone organism. His "dual hypothesis" cast the thallus as fungal tissue farming algal cells for photosynthate. Microscopy revealed algal 'gonidia' embedded in the fungal matrix, but many colleagues dismissed his reading. William Nylander repudiated the "composite" idea, viewing it as an affront to his life's work. The British lichenologist James Crombie derided the notion as a "master-and-slave" model—an enslaving parasitic fungus and its algal captive—and rebutted it in Encyclopædia Britannica. The dispute turned bitter, exposing both paradigm shock and the insularity of 19th-century lichenology. Despite the early backlash, proof for the dual hypothesis piled up during the 1870s–1880s. In 1872 Heinrich Anton de Bary—later to codify "symbiosis"—published work backing the fungal–algal alliance. Albert Frank coined "symbiose" in 1877 (de Bary anglicised it to "symbiosis" in 1879), recasting the partnership as mutualistic, not parasitic. Significantly, botanists started lab resynthesis—laboratory recreation of lichens from separated components. In 1873 Édouard Bornet matched lichen gonidia to free-living algae from 60-plus genera, proving the algae could live alone. Soon after, Hermann Reess (1872) grew fresh Collema thalli from fungal spores and algal cells; by 1886 Jules Bonnier had done the same with Xanthoria and other genera.
Argon may be used as the inert gas within Schlenk lines and gloveboxes. Argon is preferred to less expensive nitrogen in cases where nitrogen may react with the reagents or apparatus. Argon may be used as the carrier gas in gas chromatography and in electrospray ionization mass spectrometry; it is the gas of choice for the plasma used in ICP spectroscopy. Argon is preferred for the sputter coating of specimens for scanning electron microscopy. Argon gas is also commonly used for sputter deposition of thin films as in microelectronics and for wafer cleaning in microfabrication.
Given the increased expression of Hsp70 in cancer, it has been suggested as a biomarker for cancer prognostics, with high levels portending poor prognosis. An oncogenic mechanism illustrates how extracellular vesicles expressing HSP70 are produced by proliferative Acute Lymphoblastic Leukemia cells and can target and compromise a healthy hematopoiesis system during leukemia development.
Travel conditions were often extremely difficult due to the geography, climate, and lack of infrastructure across Spanish America in the early nineteenth century. The expedition frequently navigated dangerous and remote terrain. In the Orinoco basin, they traveled by canoe for weeks through dense rainforest and flooded savannahs, contending with swarms of mosquitoes and biting insects. Humboldt described suffering from fevers, likely caused by malaria or other tropical diseases, which affected both himself and Bonpland. They endured intense heat and humidity, particularly during their exploration of the Llanos and Amazonian lowlands. Food supplies were often insufficient or spoiled. Humboldt recounted periods of near-starvation, notably during their journey up the Cassiquiare Canal, when the group survived on minimal rations and local wild foods. Water was sometimes scarce or unsafe, and they risked illness from contaminated sources. The explorers faced physical dangers from local wildlife, including venomous snakes, jaguars, and crocodiles. Humboldt detailed an encounter with electric eels near Calabozo, where they observed the animals’ ability to stun horses during local fishing practices. Mountain ascents posed their own hazards. While climbing Chimborazo, Humboldt and Bonpland experienced altitude sickness, extreme cold, and exhaustion. Humboldt recorded severe headaches, nosebleeds, and difficulty breathing at high elevations.
Sources: en.wikipedia.org
It is a synthetic seven-amino-acid peptide built from the ACTH(4-7) sequence plus a Pro-Gly-Pro tail. It belongs to the family of short ACTH fragments studied for nervous-system effects. Its backbone contains only standard amino acids.
It contains the 4-7 fragment of adrenocorticotropic hormone extended at the C terminus. That truncation removes the region associated with steroidogenic activity. The design intent was to keep neurotrophic properties while avoiding full hormonal effects.
No natural source of the intact heptapeptide is known. It is produced by solid-phase peptide synthesis. Some related ACTH fragments arise as hormone processing products, but the Pro-Gly-Pro extension is a designed addition rather than a natural sequence.
It is a short synthetic peptide built from seven amino acids: methionine, glutamic acid, histidine, phenylalanine and three prolines. The sequence derives from the 4-10 fragment of adrenocorticotropic hormone with an added proline-glycine-proline tail. No plant or animal extract is involved; the material is produced by solid-phase peptide synthesis.