A practical reference on counterion: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2026-05-20. Anything still debated is marked as such rather than presented as settled.
Stability of the tetrapeptide follows ordinary peptide chemistry rather than any unusual structural feature. The aspartate-glycine pair is prone to aspartimide formation under mildly basic or neutral conditions, and deamidation can follow, altering both mass and chromatographic retention. Dry lyophilised powder kept at or below minus twenty degrees Celsius is the usual handling recommendation, with repeated freeze-thaw cycles avoided. Once dissolved in neutral aqueous buffer, degradation proceeds over days to weeks depending on pH and temperature, while acidic conditions generally slow the aspartimide route. A formal stability-indicating study has not been published in the indexed literature.
Because epitalon has no pharmacopoeial monograph, quality assessment depends on supplier documentation and independent testing. Certificates of analysis typically report a purity figure from a single chromatographic run, a measured mass and sometimes an appearance description, but methods and acceptance criteria are not harmonised across vendors. Third-party laboratories can repeat identity and purity measurements, and mismatches between labelled and measured peptide content have been described for research peptides generally. What constitutes adequate identity confirmation for a molecule of this size stays an open question, since mass agreement alone does not separate closely related sequences.
Human data are limited to small studies, often without the randomization, blinding, or control groups expected in contemporary clinical research. Reported outcomes have included changes in melatonin levels, immune markers, and subjective measures, but sample sizes were generally too small to support firm conclusions. Some reviews treat the peptide as promising while noting methodological weaknesses; others question whether the observed effects are specific. The compound is frequently discussed in longevity-focused communities, where enthusiasm often outpaces the published evidence. Separating established findings from speculation is therefore important when reading summaries of this research.
Epitalon emerged from research conducted in Saint Petersburg by Vladimir Khavinson and colleagues, who studied short peptides as potential regulators of aging. The work built on epithalamin, a pineal gland extract reported to influence neuroendocrine function. Epitalon was designed as a synthetic counterpart with a defined sequence, allowing reproducible experiments that extracts could not support. Early publications described effects on melatonin rhythms and lifespan in animal models. These findings circulated mainly in Russian-language journals during the 1990s, which limited their visibility among English-speaking researchers.
| Property | Value | Notes |
|---|---|---|
| Analytical method | Reversed-phase HPLC | Purity determination, typically 214 nm |
| Mass confirmation | ESI or MALDI mass spectrometry | Compared with mass near 390 Da |
| Common synonyms | Epitalon, epithalon, AEDG | Naming differs between suppliers |
| Storage temperature | −20 °C or lower | Lyophilised powder, kept desiccated |
| Solution stability | Limited in neutral aqueous buffer | Aspartimide and hydrolysis pathways |
Identity and purity are established with reversed-phase high-performance liquid chromatography and mass spectrometry. The chromatogram shows the main peak and any truncated or oxidised by-products, while the mass spectrum confirms the expected 390 dalton mass. Amino acid analysis can corroborate composition when a sample's origin is uncertain. Counterion content, particularly residual trifluoroacetate from purification, is frequently reported alongside purity because it shifts the net mass of the solid.
Reference material is normally supplied as a lyophilised powder in a sealed vial. Product literature typically recommends storage at minus twenty degrees Celsius or colder, protected from light and moisture. Freeze-thaw cycling is usually avoided because repeated condensation can introduce water into the vial. Working solutions are commonly prepared fresh, aliquoted, and kept cold for short periods rather than stored at ambient temperature. Labelling the date of opening helps track how long a vial has been in use.
=== In sport === It is a common practice for professional footballers (soccer players) and road cyclists to remove leg hair for a number of reasons. In the case of a crash or tackle, the absence of the leg hair means the injuries (usually road rash or scarring) can be cleaned up more efficiently, and treatment is not impeded. Professional cyclists, as well as professional footballers, also receive regular leg massages, and the absence of hair reduces the friction and increases their comfort and effectiveness. Football players are also required to wear shin guards, and in case of a skin rash, the affected area can be treated more efficiently. It is also common for competitive swimmers to shave the hair off their legs, arms, and torsos (and even their whole bodies from the neckline down), to reduce drag and provide a heightened "feel" for the water by removing the exterior layer of skin along with the body hair.
=== Arabic === Currently, the longest word in Arabic is the 16-letter-long word أَفَإِستَسقَينَاكُمُوهما. Which means "Did we ask you to let us drink them both?" However, according to some online sources the 20-letter-long word أَفَيَسْتَكْتِبونَكُمانيهِما is the longest word in Arabic meaning "Are they forcing you to write both of them?". Regardless, official sources supporting such a stance cannot be found.
=== Simplicity === Living organisms are extremely complex functional systems that are made up of, at a minimum, many tens of thousands of genes, protein molecules, RNA molecules, small organic compounds, inorganic ions, and complexes in an environment that is spatially organized by membranes, and in the case of multicellular organisms, organ systems. These myriad components interact with each other and with their environment in a way that processes food, removes waste, moves components to the correct location, and is responsive to signalling molecules, other organisms, light, sound, heat, taste, touch, and balance.
Angiogenin (ANG) also known as ribonuclease 5 is a small 123 amino acid protein that in humans is encoded by the ANG gene. Angiogenin is a potent stimulator of new blood vessels through the process of angiogenesis. Ang hydrolyzes cellular RNA, resulting in modulated levels of protein synthesis and interacts with DNA causing a promoter-like increase in the expression of rRNA. Ang is associated with cancer and neurological disease through angiogenesis and through activating gene expression that suppresses apoptosis.
=== Pharmacokinetics === The pharmacokinetics of phenylpiracetam in humans are unpublished. In any case, the drug is described as having an oral bioavailability of approximately 100%, as having an onset of action of less than 1 hour, as not being metabolized, as being excreted unchanged about 40% in urine and 60% in bile and sweat, and as having an elimination half-life of 3 to 5 hours. In rodents, its absorption occurs within 1 hour with oral administration or intramuscular injection and its elimination half-life is 2.5 to 3 hours.
Sources: en.wikipedia.org
== Author == Fascia: The Tensional Network of the Human Body: The science and clinical applications in manual and movement therapy. Elsevier Health Sciences. 26 February 2013. ISBN 978-0-7020-5228-6. Fascia in Sport and Movement. Handspring. 2015. ISBN 978-1-909141-07-0. Fascial Fitness: How to be Vital, Elastic and Dynamic in Everyday Life and Sport. Lotus. 2017. ISBN 978-1-905367-71-9. Fascia: The Tensional Network of the Human Body Expert Consult: Fascia: The Tensional Network of the Human Body - E-Book. Elsevier Health Sciences. 8 December 2021. ISBN 978-0-7020-8413-3. Fascial Fitness, Second Edition: Practical Exercises to Stay Flexible, Active and Pain Free in Just 20 Minutes a Week. North Atlantic Books. 6 July 2021. ISBN 978-1-62317-675-4. Fascia in Sport and Movement, Second edition. Jessica Kingsley Publishers. 30 March 2021. ISBN 978-1-912085-78-1. Der Faszien-Code: Wie die Genetik des Bindegewebes deine Gesundheit beeinflusst und du typgerecht trainierst, um Beweglichkeit und Fitness zu optimieren. Riva Verlag. 18 February 2024. ISBN 978-3-7453-2298-9.
=== Electrolytes === In the initial stages, electrolyte levels are often abnormal and require correction. High potassium levels can be life-threatening, and respond to increased urine production and renal replacement therapy (see below). Temporary measures include the administration of calcium to protect against cardiac complications, insulin or salbutamol to redistribute potassium into cells, and infusions of bicarbonate solution. Calcium levels initially tend to be low, but as the situation improves, calcium is released from where it has precipitated with phosphate, and vitamin D production resumes, leading to hypercalcemia (abnormally high calcium levels). This "overshoot" occurs in 20–30% of those people who have developed kidney failure.
== Reaction == The text of the declaration was published in the press one week after it was signed, on 9 November 1917. Other related events took place within a short timeframe, the two most relevant being the almost immediate British military capture of Palestine and the leaking of the previously secret Sykes–Picot Agreement. On the military side, both Gaza and Jaffa fell within several days, and Jerusalem was surrendered to the British on 9 December. The publication of the Sykes–Picot Agreement, following the Russian Revolution, in the Bolshevik Izvestia and Pravda on 23 November 1917 and in the British Manchester Guardian on 26 November 1917, represented a dramatic moment for the Allies' Eastern campaign: "the British were embarrassed, the Arabs dismayed and the Turks delighted." The Zionists had been aware of the outlines of the agreement since April and specifically the part relevant to Palestine, following a meeting between Weizmann and Cecil where Weizmann made very clear his objections to the proposed scheme.
The superoxide ion, O−2 is generated in biological systems by reduction of molecular oxygen. It has an unpaired electron, so it behaves as a free radical. It is a powerful oxidizing agent. These properties render the superoxide ion very toxic and are deployed to advantage by phagocytes to kill invading microorganisms. Otherwise, the superoxide ion must be destroyed before it does unwanted damage in a cell. The superoxide dismutase enzymes perform this function very efficiently. The formal oxidation state of the oxygen atoms is −1⁄2. In solutions at neutral pH, the superoxide ion disproportionates to molecular oxygen and hydrogen peroxide.
The Rhodesian army continued its "mobile counter-offensive" strategy of holding key positions ("vital asset ground") while carrying out raids into the no-go areas and into neighbouring countries. While often extraordinarily successful in inflicting heavy guerrilla casualties, such raids also on occasion failed to achieve their objectives. In April 1979 special forces carried out a raid on Joshua Nkomo's residence in Lusaka, Zambia, with the stated intention of assassinating him. Nkomo and his family left hastily a few hours before the raid – having clearly been warned that the raid was coming. In 1979, some special forces units were accused of using counterinsurgent operations as cover for ivory poaching and smuggling. Colonel Reid-Daly (commander of the Selous Scouts) discovered that his phone was bugged and after challenging a superior officer on this issue was court martialled for insubordination. He received the lightest sentence possible, a caution, but he continued to fight his conviction and eventually resigned his commission and left the Army. By 1978–1979, up to 70% of the regular army was composed of black soldiers (though both the army and police reserves remained overwhelmingly white). By 1979 there were also 30 black commissioned officers in the regular army. While there was never any suggestion of disloyalty among the soldiers from predominantly black units (in particular within the Selous Scouts or the Rhodesian African Rifles – RAR), some argue that, by the time of the 1980 election, many of the RAR soldiers voted for Robert Mugabe.
Sources: en.wikipedia.org
Iron shows the characteristic chemical properties of the transition metals, namely the ability to form variable oxidation states differing by steps of one and a very large coordination and organometallic chemistry: indeed, it was the discovery of an iron compound, ferrocene, that revolutionalized the latter field in the 1950s. Iron is sometimes considered as a prototype for the entire block of transition metals, due to its abundance and the immense role it has played in the technological progress of humanity. Its 26 electrons are arranged in the configuration [Ar]3d64s2, of which the 3d and 4s electrons are relatively close in energy, and thus a number of electrons can be ionized. Iron forms compounds mainly in the oxidation states +2 (iron(II), "ferrous") and +3 (iron(III), "ferric"). Iron also occurs in higher oxidation states, e.g., the purple potassium ferrate (K2FeO4), which contains iron in its +6 oxidation state. The anion FeO4− with iron in its +7 oxidation state, along with an iron(V)-peroxo isomer, has been detected by infrared spectroscopy at 4 K after cocondensation of laser-ablated Fe atoms with a mixture of O2/Ar. An iron(VII) terminal nitride has been synthesized and spectroscopically characterized. Iron(IV) is a common intermediate in many biochemical oxidation reactions. Numerous organoiron compounds contain formal oxidation states of +1, 0, −1, or even −2. The oxidation states and other bonding properties are often assessed using the technique of Mössbauer spectroscopy.
Most infants with CMD will display some progressive muscle weakness or muscle wasting (atrophy), although there can be different degrees and symptoms of severeness of progression. The weakness is indicated as hypotonia, or lack of muscle tone, which can make an infant seem unstable. Eventually, most patients develop joint contractures or fixed joint deformities. Children may be slow with their motor skills; such as rolling over, sitting up or walking, or may not even reach these milestones of life. Some of the rarer forms of CMD can result in significant learning disabilities.
==== Kasukawa criteria ==== The Kasukawa criteria require a minimum of one of the common symptoms, a positive anti-RNP antibody, as well as one or more symptoms of the mixed symptoms in at least two of the three disease categories to qualify for a diagnosis of MCTD. It has a sensitivity of 75% and a specificity of 99.8%. Common symptoms:
=== Death === Kratom overdose is a subject of concern in many countries because of the associated rising number of hospitalizations and deaths in which chronic kratom use is a contributing factor. According to clinical reviews, a kratom overdose can cause liver toxicity, seizures, coma, and death, especially in combination with excessive alcohol use. Between 2011 and 2017, 44 U.S. deaths were kratom-related. However, many cases could not be fully assessed, due to limited information. People who die from kratom use typically have taken it in combination with other substances, or have underlying health conditions. Over 18 months in 2016 and 2017, 152 overdose deaths involving kratom were reported in the United States, with kratom as the primary overdose agent in 91 of the deaths, and 7 with kratom being the only agent detected. Nine deaths occurred in Sweden during 2010–11 relating to use of Krypton, a mixture of kratom, caffeine and O-desmethyltramadol, a metabolite of the opioid analgesic tramadol. Between 2020 and 2024, the Centers for Disease Control and Prevention found that kratom was involved in over 5,200 fatal overdoses in the United States.
"Before melamine, the dealers added rice porridge or starch into the milk to artificially boost the protein count, but that method was easily tested as fake, so they switched to melamine,” said Zhao Huibin, a dairy farmer near Shijiazhuang. Investigators say the adulteration was nothing short of a wholesale re-engineering of milk. Researchers established that workers at Sanlu and at a number of milk-collection depots were diluting milk with water; they added melamine to dupe a test for determining crude protein content. "Adulteration used to be simple. What they did was very high-tech", says Chen Junshi, co-chair of the Sino-U.S. workshop and a risk-assessment specialist at China's Center for Disease Control and Prevention. Investigators subsequently learned that the emulsifier used to suspend melamine also boosted apparent milk-fat content. Sanlu baby formula contained a whopping 2563 mg/kg of melamine, adding 1% of apparent crude protein content to the formula, where normal milk is 3.0% to 3.4% protein. Chen says a dean of a school of food science told him that it would take a university team 3 months to develop this kind of concoction. Investigators have concluded that as-yet-unidentified individuals cooked up a protocol for a premix, a solution normally designed to fortify foods with vitamins or other nutrients but, in this case, it was poisonous. Several milk-collecting companies were using the same premix, Chen says: "So someone with technical skill had to be training them."
Sources: en.wikipedia.org
The molecule lacks aromatic residues, so it absorbs weakly near 280 nanometres, the wavelength applied to many other peptides. The peptide bond absorbs strongly below 220 nanometres, making 214 nanometres a practical compromise. Gradient methods must therefore use mobile phases with low ultraviolet absorbance to keep the baseline clean.
Neutral and slightly basic aqueous conditions promote aspartimide formation at the aspartate-glycine step, often followed by deamidation. Elevated temperature and repeated freeze-thaw cycles accelerate the loss. Acidic solutions and dry lyophilised powder are comparatively stable over short periods.
No monograph exists in the United States Pharmacopeia or the European Pharmacopoeia, and no widely distributed certified reference standard is available. Purity and identity therefore rest on supplier methods that are not harmonised. This absence is the main reason reported purities are difficult to compare between sources.
Vladimir Khavinson and colleagues at research institutes in Saint Petersburg developed and studied the peptide. Their program examined short peptides as regulators of aging and neuroendocrine function. Epitalon was one of several compounds produced by that group.