This is a working overview of ACTH analog, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2025-11-23. Anything still debated is marked as such rather than presented as settled.
Identity and purity are confirmed with reversed-phase high-performance liquid chromatography, typically monitored at 214 nanometres where the peptide bond absorbs. Mass spectrometry, either electrospray or MALDI-TOF, verifies molecular mass against the theoretical value and detects truncation or adduct formation. Amino acid analysis and peptide mapping provide additional confirmation when required. The most frequently reported impurities are deletion sequences from incomplete coupling, methionine sulfoxide from oxidation, and dimeric species formed through non-covalent aggregation. Impurity profiles depend strongly on the synthesis and purification route chosen by the producer.
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.
Later generations of the molecule include an N-acetylated form and an amidated form, both marketed online alongside the parent peptide. These variants differ in terminal chemistry and stability, and they are frequently discussed in the same breath even though they have not been compared in controlled trials. Supply outside formal healthcare systems comes largely from laboratories that synthesize peptides to order. Purity and identity of these materials vary widely, and no single body oversees the international trade.
Semax is a synthetic heptapeptide developed in the Soviet Union during the 1980s by researchers at the Institute of Molecular Genetics in Moscow. It was designed as a truncated analog of adrenocorticotropic hormone, retaining only the fragment spanning residues four through ten. Investigators sought a peptide that would preserve the cognitive effects associated with ACTH while eliminating the hormonal stimulation of the adrenal cortex. The compound entered clinical use in Russia during the following decade.
| 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 |
纯度评估以反相高效液相色谱为主，通过主峰面积百分比给出粗略结果，再配合电喷雾质谱核对分子量。氨基酸分析可验证组成比例，手性色谱或毛细管电泳用于检查残基构型。常见杂质包括缺失序列的短肽、氧化产物与二聚体。由于多数市售品不附带完整检验报告，独立第三方检测常被用来核实标称值。
从分子层面看，Semax 是线性七肽，没有二硫键、糖基或脂链修饰，N 端为游离氨基，C 端为游离羧基。分子含组氨酸与谷氨酸侧链，因此在水和甲醇等极性溶剂中溶解良好，在非极性溶剂中溶解有限。计算分子量约为 814 Da，与其质子化离子的质荷比吻合，可用于质谱确认。
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.
The proposed mechanism centres on neurotrophic signalling rather than direct receptor activation. Semax is reported to increase expression of brain-derived neurotrophic factor and nerve growth factor in several brain regions, and to shift the balance between excitatory and inhibitory neurotransmitter systems. Interaction with melanocortin receptors has been suggested because of the parent ACTH fragment. Many of these findings come from rodent studies, and the extent to which they translate to human physiology remains an open question.
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.
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.
SLC is the root name (SoLute Carrier) n = an integer representing a family (e.g., 1-52) X = a single letter (A, B, C, ...) denoting a subfamily m = an integer representing an individual family member (isoform). For example, SLC1A1 is the first isoform of subfamily A of SLC family 1. An exception occurs with SLC family 21 (the organic anion transporting polypeptide transporters), which for historical reasons have names in the format SLCOnXm where n = family number, X = subfamily letter, and m = member number. While the HGNC only assign nomenclature to human genes, by convention vertebrate orthologs of these genes adopt the same nomenclature (e.g., VGNC-assigned orthologs of SLC10A1). For rodents, the case of the symbols differs from other vertebrates by using title case, i.e. Slc1a1 denotes the rodent ortholog of the human SLC1A1 gene.
== Particle physics == Quarks and gluons have color charge, which is always conserved like electric charge, and there is a continuity equation for such color charge currents (explicit expressions for currents are given at gluon field strength tensor). There are many other quantities in particle physics which are often or always conserved: baryon number (proportional to the number of quarks minus the number of antiquarks), electron number, mu number, tau number, isospin, and others. Each of these has a corresponding continuity equation, possibly including source / sink terms.
It was traditionally assumed that the first reptiles retained an anapsid skull inherited from their ancestors. This type of skull has a skull roof with only holes for the nostrils, eyes and a pineal eye. The discoveries of synapsid-like openings (see below) in the skull roof of the skulls of several members of Parareptilia (the group containing most of the amniotes traditionally referred to as "anapsids"), including lanthanosuchoids, millerettids, bolosaurids, some nycteroleterids, some procolophonoids and at least some mesosaurs made it more ambiguous and it is currently uncertain whether the ancestral amniote had an anapsid-like or synapsid-like skull. These animals are traditionally referred to as "anapsids", and form a paraphyletic basic stock from which other groups evolved. Very shortly after the first amniotes appeared, a lineage called Synapsida split off; this group was characterized by a temporal opening in the skull behind each eye giving room for the jaw muscle to move. These are the "mammal-like amniotes", or stem-mammals, that later gave rise to the true mammals. Soon after, another group evolved a similar trait, this time with a double opening behind each eye, earning them the name Diapsida ("two arches"). The function of the holes in these groups was to lighten the skull and give room for the jaw muscles to move, allowing for a more powerful bite.
Sir Frederick Grant Banting (; November 14, 1891 – February 21, 1941) was a Canadian pharmacologist, orthopedist, and field surgeon. For his co-discovery of insulin and its therapeutic potential, Banting was awarded the Nobel Prize in Physiology or Medicine with John Macleod. Banting and his student, Charles Best, isolated insulin at the University of Toronto in the lab of Scottish physiologist John Macleod. When he and Macleod received the 1923 Nobel Prize in Physiology or Medicine, Banting shared the honours and award money with Best. That same year, the Government of Canada granted Banting a lifetime annuity to continue his work. He is the youngest Nobel laureate for Physiology/Medicine, at 32.
=== Superhydrophobic surfaces === A superhydrophobic surface is a low energy, generally rough surface on which water has a contact angle of >150°. Nonpolar materials such as hydrocarbons traditionally have relatively low surface energies, however, this property alone is insufficient to achieve superhydrophobicity. Superhydrophobic surfaces can be created in many ways, however, most of the synthesis strategies are inspired by natural designs. The Cassie-Baxter model provides an explanation for superhydropbicity—air trapped in microgrooves of a rough surface creates a "composite" surface consisting of air and the tops of microprotrusions. This structure is maintained as the scale of the features decreases, thus many approaches to the synthesis of superhydrophobic surfaces have focused on the fractal contribution. Wax solidification, lithography, vapor deposition, template methods, polymer reconfirmation, sublimation, plasma, electrospinning, sol-gel processing, electrochemical methods, hydrothermal synthesis, layer-by-layer deposition, and one-pot reactions are approaches to the creation of superhydrophobic surfaces that have been suggested. Making a surface superhydrophobic represents an efficient means of imparting antimicrobial activity. A passive antibacterial effect results from the poor ability of microbes to adhere to the surface. The area of superhydrophobic textiles takes advantage of this and could have potential applications as antimicrobial coatings.
Sources: en.wikipedia.org
=== War in Yemen (2014–present) === Yemen was riven in 2015, with the Houthis establishing a new government in Sanaa and Hadi retreating with his supporters to Aden, and later Saudi Arabia. The Arab League, led by the Saudis, began a bombing campaign and mobilization of various armed forces in the region for a possible invasion.
== Genes == In humans, the gene for the alpha subunit is located at cytogenetic location 6q14.3. It is expressed in two cell types, most notably the basophils of the anterior pituitary. The gene for the FSH beta subunit is located on chromosome 11p13, and is expressed in gonadotropes of the pituitary cells, controlled by GnRH, inhibited by inhibin, and enhanced by activin.
UK-414,495 is a drug developed by Pfizer for the treatment of female sexual arousal disorder. UK-414,495 acts as a potent, selective inhibitor of the enzyme neutral endopeptidase, which normally serves to break down the neuropeptide VIP. The consequent increase in VIP activity alters blood flow to the genital region leading to increased lubrication and muscle relaxation.
The two substrates of this enzyme are scytalone and oxidised nicotinamide adenine dinucleotide phosphate (NADP+). Its products are naphthalene-1,3,6,8-tetrol, reduced NADPH, and a proton. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-OH group of donor with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is scytalone:NADP+ Delta5-oxidoreductase.
Schleswig-Holstein () is a coastal state that is the northernmost of the sixteen states of Germany, comprising most of the historical Duchy of Holstein and the southern part of the former Duchy of Schleswig. It borders Denmark, Mecklenburg-Vorpommern, Lower Saxony and the city-state of Hamburg. Its capital city is Kiel; other notable cities are Lübeck and Flensburg. It covers an area of 15,763 km2 (6,086 sq mi), making it the 5th smallest German state by area (including the city-states). Historically, the name can also refer to a larger region, containing both present-day Schleswig-Holstein and the former South Jutland County (Northern Schleswig; now part of the Region of Southern Denmark) in Denmark. Schleswig, known as South Jutland at the time, had been under Danish control since the fifth century. In the 12th century, however, it became a duchy within Denmark due to infighting in the Danish royal house. It bordered Holstein, which was a part of the Holy Roman Empire. Beginning in 1460, the King of Denmark ruled both Schleswig and Holstein as their duke. Schleswig was still part of Denmark, while Holstein remained part of the Holy Roman Empire. In the 19th century, both Danes and Germans believed they had a rightful claim to Schleswig-Holstein. While the population of Holstein and Lauenburg was entirely ethnically German, Schleswig had been predominantly Danish until the late 1700s and early 1800s, when extensive German influence led to the Germanization of South Schleswig.
Sources: en.wikipedia.org
==== France ==== The first location in France opened in Paris in May 2012. Expansion in France was much slower than that in the United Kingdom or Canada, with a second location in Paris opening in 2013 and a third location in 2014. At the time of its opening in 2014, the restaurant at La Défense was the largest Chipotle location in the world at 7,000 square feet (650 m2), while a typical Chipotle restaurant is usually between 2,200 square feet (200 m2) and 2,500 square feet (230 m2). A fourth Parisian location was opened in Levallois-Perret in 2015 followed by a fifth Parisian location in Saint-Germain-des-Prés in 2016. The company opened its seventh location in France and its first location outside the Paris region, inside Lyon's La Part-Dieu shopping mall in 2021.
==== Netherlands ==== In the Netherlands, 2C-B was scheduled on July 9, 1997. In the Netherlands, 2C-B became a list I substance of the Opium Law despite no health incidents occurring. Following the ban, other phenethylamines were sold in place of 2C-B until the Netherlands became the first country in the world to ban 2C-I, 2C-T-2 and 2C-T-7 alongside 2C-B.
=== Bibliography === Emsley, John (2003). Nature's building blocks: an A-Z guide to the elements. Oxford University Press. p. 351 ff. ISBN 978-0-19-850340-8. Retrieved 27 June 2015. Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. doi:10.1016/C2009-0-30414-6. ISBN 978-0-08-037941-8. Keller, Cornelius; Wolf, Walter; Shani, Jashovam (15 October 2011). "Radionuclides, 2. Radioactive Elements and Artificial Radionuclides". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. pp. 97–98. doi:10.1002/14356007.o22_o15. ISBN 978-3-527-30673-2. Kirby, H.W. & Salutsky, Murrell L. (December 1964). The Radiochemistry of Radium (Report). crediting UNT Libraries Government Documents Department – via University of North Texas, UNT Digital Library. Alternate source: https://sgp.fas.org/othergov/doe/lanl/lib-www/books/rc000041.pdf
Intracrines play a crucial role in maintaining stem cell populations and guiding their differentiation into specialized cell types. Many stem cell regulatory proteins, including vascular endothelial growth factor (VEGF), high-mobility group protein B1 (HMGB1), and homeodomain transcription factors such as Pax6 and Oct3/4, operate through intracrine mechanisms. These factors establish intracellular feedback loops that sustain differentiation programs, ensuring that once a stem cell commits to a particular lineage, the developmental process continues even after the external signal is removed. For instance, VEGF, a well-known angiogenic factor, is also an intracrine that promotes the survival and differentiation of hematopoietic stem cells. In VEGF-deficient cells, survival and colony formation are impaired, but these defects can be rescued by restoring intracellular VEGF levels, highlighting the necessity of intracrine VEGF in stem cell regulation. Similarly, the homeodomain transcription factor Pdx-1 can be internalized by target cells, where it upregulates its own synthesis and drives pancreatic duct cells toward an insulin-producing phenotype, demonstrating the ability of intracrines to induce cell fate changes.
The thyroid hormone is critical to the normal function of cells. In excess, it both overstimulates metabolism and disrupts the normal functioning of the sympathetic nervous system, causing speeding up of various body systems and symptoms resembling an overdose of epinephrine (adrenaline). These include fast heartbeat and symptoms of palpitations, nervous system tremor such as of the hands and anxiety symptoms, digestive system hypermotility, unintended weight loss, and, in lipid panel blood tests, a lower and sometimes unusually low serum cholesterol. Major clinical signs of hyperthyroidism include weight loss (often accompanied by an increased appetite), anxiety, heat intolerance, hair loss, muscle aches, weakness, fatigue, hyperactivity, irritability, high blood sugar, excessive urination, excessive thirst, delirium, tremor, pretibial myxedema (in Graves' disease), emotional lability, and sweating. Panic attacks, inability to concentrate, and memory problems may also occur. Psychosis and paranoia, common during thyroid storm, are rare with milder hyperthyroidism. Many persons will experience complete remission of symptoms 1 to 2 months after a euthyroid state is obtained, with a marked reduction in anxiety, sense of exhaustion, irritability, and depression. Some individuals may have an increased rate of anxiety or persistence of affective and cognitive symptoms for several months to up to 10 years after a euthyroid state is established.
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 originated at the Institute of Molecular Genetics in Moscow during the 1980s. The work was carried out by a Russian research group that specialized in peptide neuropharmacology.