ACTH(4–10) 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 2026-01-03. Numbers and descriptions here follow the published literature rather than marketing material.
Common degradation pathways include oxidation of the methionine side chain, hydrolysis of the peptide backbone, and aggregation under unfavourable pH or concentration. Stability studies typically monitor the main peak by chromatography and report total related substances as a percentage. Because no official monograph exists, acceptance criteria vary between laboratories, and reported purity values are not directly comparable across suppliers. Analysts therefore document the method, column, and detection wavelength alongside each result, and open questions remain about how much biological activity the oxidised forms retain.
Solid semax is typically supplied as a lyophilised powder that is hygroscopic and sensitive to moisture, light, and repeated temperature cycling. Long-term storage of the dry peptide is generally recommended at approximately -20 degrees Celsius, while shorter working periods may use refrigeration at 2 to 8 degrees Celsius. Vials should remain tightly closed and desiccated when brought to room temperature, because condensation can damage the material before it is weighed. Dividing a batch into aliquots is preferable to thawing one container repeatedly.
Dissolution is normally performed in water, phosphate-buffered saline, or normal saline, since the peptide is freely soluble in aqueous media and is rarely handled with strong organic solvents. Solution pH should be kept near neutral, because extreme acidity or alkalinity accelerates backbone hydrolysis and encourages oxidation of the methionine side chain. Once dissolved, the material is less stable than the dry powder and is commonly divided into single-use portions and frozen. Buffers containing primary amines, such as Tris, are often avoided because of possible side reactions.
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.
Clinical reports describe use in ischaemic stroke, transient ischaemic attack, optic nerve conditions, and cognitive complaints, but most of these studies are small and were conducted in a single region. Systematic reviews have generally described the evidence base as limited in size and variable in methodological quality. Randomised controlled data suitable for international regulatory assessment are scarce. As a result, major treatment guidelines outside Russia do not include the peptide, and interest in it remains largely research-driven rather than routine clinical.
| Property | Value | Notes |
|---|---|---|
| Typical analytical method | Reversed-phase HPLC with UV detection | Separates target peptide from truncated and oxidised forms |
| Identity confirmation | LC-MS or ESI-MS | Compares observed and calculated molecular ion |
| Primary degradation route | Methionine oxidation | Forms the sulfoxide; monitored as an early-eluting peak |
| Short-term storage | 2 to 8 degrees Celsius | Applies to working vials and reconstituted portions |
| Common synonyms | ACTH(4–10) analogue, MEHFPGP | Descriptive names used in laboratory catalogues |
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.
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.
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.
Terminology around the compound varies by source. It appears in catalogues and papers as Semax, as the heptapeptide ACTH(4-7)-Pro-Gly-Pro, and under various alphanumeric laboratory codes used by individual suppliers. These names refer to the same sequence but may imply different salt forms, purity grades, or counter-ions. Peptide databases usually list the free base mass, while product descriptions sometimes report acetate or trifluoroacetate salts with a different formula weight. Because naming conventions for research peptides are not standardised across vendors, checking the declared sequence and measured mass is more reliable than relying on a trade name alone.
In several countries, the illegal drug trade is thought to be directly linked to violent crimes such as murder and gun violence. This is especially true in all developing countries, such as Honduras, but is also an issue for many developed countries worldwide. In the late 1990s in the United States, the Federal Bureau of Investigation estimated that 5% of murders were drug-related. In Colombia, drug violence can be caused by factors such as the economy, poor governments, and no authority within law enforcement. After a crackdown by US and Mexican authorities in the first decade of the 21st century as part of tightened border security in the wake of the September 11 attacks, border violence inside Mexico surged. The Mexican government estimated that 90% of the killings were drug-related. A report by the UK government's Drug Strategy Unit that was leaked to the press, stated that due to the expensive price of highly addictive drugs heroin and cocaine, drug use was responsible for the great majority of crime, including 85% of shoplifting, 70–80% of burglaries and 54% of robberies. It concluded "[t]he cost of crime committed to support illegal cocaine and heroin habits amounts to £16 billion a year in the UK"
== Synthesis, structure, and reactivity == Although fluorene is obtained from coal tar, it can also be prepared by dehydrogenation of diphenylmethane. Alternatively, it can be prepared by the reduction of fluorenone with zinc or hypophosphorous acid–iodine. The fluorene molecule is nearly planar, although each of the two benzene rings is coplanar with the central carbon 9. Fluorene can be found after the incomplete combustion of plastics such as polystyrene, polyethylene and polyvinyl chloride.
== Further reading == Fitzgerald J, Bateman JF (September 2001). "A new FACIT of the collagen family: COL21A1". FEBS Letters. 505 (2): 275–280. doi:10.1016/S0014-5793(01)02754-5. PMID 11566190. Chou MY, Li HC (March 2002). "Genomic organization and characterization of the human type XXI collagen (COL21A1) gene". Genomics. 79 (3): 395–401. doi:10.1006/geno.2002.6712. PMID 11863369.
The vagina is the birth canal for the delivery of a baby. When labor nears, several signs may occur, including vaginal discharge and the rupture of membranes (water breaking). The latter results in a gush or small stream of amniotic fluid from the vagina. Water breaking most commonly happens at the beginning of labor. It happens before labor if there is a premature rupture of membranes, which occurs in 10% of cases. Among women giving birth for the first time, Braxton Hicks contractions are mistaken for actual contractions, but they are instead a way for the body to prepare for true labor. They do not signal the beginning of labor, but they are usually very strong in the days leading up to labor. As the body prepares for childbirth, the cervix softens, thins, moves forward to face the front, and begins to open. This allows the fetus to settle into the pelvis, a process known as lightening. As the fetus settles into the pelvis, pain from the sciatic nerves, increased vaginal discharge, and increased urinary frequency can occur. While lightening is likelier to happen after labor has begun for women who have given birth before, it may happen ten to fourteen days before labor in women experiencing labor for the first time. The fetus begins to lose the support of the cervix when contractions begin. With cervical dilation reaching 10 cm to accommodate the head of the fetus, the head moves from the uterus to the vagina. The elasticity of the vagina allows it to stretch to many times its normal diameter in order to deliver the child.
Sources: en.wikipedia.org
Plutonium-244 is one of several extinct radionuclides that preceded the formation of the Solar System. Its half-life of 81.3 million years ensured its circulation across the Solar System before its extinction, and so evidence of it should also be found throughout the Solar System. Radionuclides such as 244Pu, decay to produce fissiogenic (i.e., arising from fission) xenon isotopes that can then be used to time the events of the early Solar System. In fact, by analyzing data from Earth's mantle which indicates that about 30% of existing fissiogenic xenon is from 244Pu decay, it can be inferred that the Earth formed nearly 50–70 million years after the Solar System formed. Before the analysis of mass spectroscopy data from analyzing samples found in meteorites, it was inferential at best to credit 244Pu as being the nuclide responsible for the fissiogenic xenon found. However, an analysis of a laboratory sample of 244Pu compared with that of fissiogenic xenon gathered from the meteorites Pasamonte and Kapoeta produced matching spectra that immediately left little doubt as to the source of the isotopic xenon anomalies. Spectra data was further acquired for another actinide isotope, 244Cm, but such data proved contradictory and helped erase further doubts that the fission was appropriately attributed to 244Pu. Both the examination of spectra data and study of fission tracks led to several findings of plutonium-244. In Western Australia, the analysis of the mass spectrum of xenon in 4.1–4.2-billion-year-old zircons was met with findings of diverse levels of 244Pu fission.
There are many types of freeze-dryers available, however, they usually contain a few essential components. These are a vacuum chamber, shelves, process condenser, shelf-fluid system, refrigeration system, vacuum system, and control system.
=== Vietnamese === In Vietnam, Chinese-style soy sauce is called xì dầu (derived from the Cantonese name 豉油) or nước tương. The term "soy sauce" could also imply other condiments and soy bean paste with thick consistency known as tương. Both are used mostly as a seasoning or dipping sauce for a number of dishes. Vietnamese cuisine itself favors fish sauce in cooking, but nước tương has a clear presence in vegetarian cuisine and Buddhist cuisine.
Sources: en.wikipedia.org
Among the 16 genes, the analysis identified two for which rare mutations are known to cause monogenic obesity: MC4R and PCSK1 (proprotein convertase subtilisin/kexin type 1). One study provides genetic evidence linking rare coding variation to BMI and obesity-related phenotypes. MC4R gene mutations are associated with early-onset severe obesity. The effect of two exemplary heterozygous coding variants in the MC4R gene (C293R and S94N) are: • Rapid weight gains from early age (the most important feature). • Development of severe obesity (BMI ≫97th percentile) at early ages, usually <3 years of age. • Persistent food-seeking behavior, mostly reported from six months of age. • Parental/siblings anthropometric data: suspect if relatives present normal anthropometric data. • Tall stature/increased growth velocity (MC4R monogenic diabetes). There is limited treatment options for the most common form of monogenic obesity, MC4R mutations symptoms can be treated with a Glucagon-like Peptide-1 Receptor Agonist liraglutide which cause weight loss by reducing appetite. They found that the effects of liraglutide 3.0 mg daily for 16 weeks causes weight reducing and glucose lowering and may be relevant treatment in the most common form of monogenic obesity.
Ganapati (2008) defines these categories as the following:In Tenure co-operatives, members collectively own and manage housing, similar to co-operative housing in the Western countries. Finance co-operatives provide loans for new construction or housing repairs to members. Building co-operatives construct housing for their members, but they may also be involved in land development.
== Graphene analogs == Graphene analogs (also referred to as "artificial graphene") are two-dimensional systems which exhibit similar properties to graphene. Graphene analogs have been studied intensively since the discovery of graphene in 2004. People try to develop systems in which the physics is easier to observe and manipulate than in graphene. In those systems, electrons are not always the particles that are used. They might be optical photons, microwave photons, plasmons, microcavity polaritons, or even atoms. Also, the honeycomb structure in which those particles evolve can be of a different nature than carbon atoms in graphene. It can be, respectively, a photonic crystal, an array of metallic rods, metallic nanoparticles, a lattice of coupled microcavities, or an optical lattice.
Sources: en.wikipedia.org
Dry powder is usually kept at about -20 degrees Celsius for long-term storage and at 2 to 8 degrees Celsius for short working periods. Containers should stay sealed and protected from light and moisture to limit degradation.
Oxidation of the methionine residue to the sulfoxide is a frequently reported change, and it usually appears as an earlier-eluting peak in reversed-phase chromatography. Backbone hydrolysis products can also accumulate in aqueous solution.
Liquid chromatography coupled with mass spectrometry is the usual approach, because the observed molecular ion can be compared with a calculated mass of about 813.9 Da. Retention time alone does not establish identity.
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.