The short version of counter-ion fits in a sentence. The long version — which is the one that helps — is below.
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Epitalon is a synthetic four-amino-acid peptide with the sequence alanine-glutamate-aspartate-glycine, commonly abbreviated AEDG. Its molecular formula is C14H22N4O9, and its calculated molar mass is approximately 390.35 grams per mole. The compound is a short fragment related to a peptide fraction isolated from bovine pineal gland extracts, and it is normally supplied as a lyophilised powder intended for laboratory research. It is not a registered pharmaceutical product in most countries.
The peptide emerged from research carried out in Saint Petersburg from the late 1980s onward, where investigators searched for shorter active fragments of a pineal preparation known as epithalamin. The name epitalon was chosen to reflect that parent extract. Early reports described effects on neuroendocrine markers and on the lifespan of laboratory animals. Much of that work appeared in Russian-language journals, with English translations following later, which affects how readily the original protocols can be assessed by outside groups.
Published studies on epitalon are dominated by a small number of research groups, and independent replication in other laboratories remains limited. Proposed mechanisms include activation of telomerase and modulation of melatonin rhythms, but the evidence for either rests mainly on cell cultures and animal models. Whether the peptide produces comparable effects in humans is an open question, and the absence of large controlled trials means the literature is best read as exploratory rather than settled.
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.
Solubility is high in water, phosphate-buffered saline and normal saline, a pattern that follows from the two acidic residues in the chain. The peptide dissolves poorly in non-polar solvents such as hexane or chloroform. Stock solutions are often prepared in water first and then diluted into the buffer of interest. Because the molecule is small and hydrophilic, filtration through a low-protein-binding membrane is usually straightforward, and visible particulates are uncommon in freshly made solutions.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C14H22N4O9 | Derived from the four-residue sequence |
| Molar mass | About 390.35 g/mol | Free peptide, counter-ion not included |
| Appearance | White to off-white powder | Lyophilised solid from aqueous solution |
| Water solubility | Freely soluble | Short, polar peptide chain |
| Common synonyms | AEDG; epithalone | Catalogues use the names interchangeably |
Discussions in the literature often conflate three distinct entities: the pineal extract epithalamin, the isolated tetrapeptide AEDG, and commercial preparations sold under similar names. Reviews citing older Russian-language studies sometimes omit detail on purity, route of administration and control groups, which makes cross-study comparison difficult. Researchers working with the compound generally note the need for independent replication, standardized enzyme assays, and clearer reporting of peptide identity. These caveats are relevant when weighing claims that appear in secondary sources rather than in primary reports.
（TG:@pojiaai）Epitalon is a synthetic linear tetrapeptide with the sequence alanine-glutamate-aspartate-glycine, abbreviated AEDG. It emerged from work on epithalamin, a peptide fraction prepared from bovine pineal tissue, and was designed as a short, chemically defined analogue of that extract. Early publications came mainly from Russian laboratories studying pineal peptides and aging-related endpoints. The compound appears in the literature under several spellings, including epithalon and epithalone, which complicates systematic searching. Its small size makes solid-phase assembly and routine analytical characterization straightforward.
The molecule is a short, linear, hydrophilic peptide that dissolves readily in water or aqueous buffer. Its principal chemical liabilities are hydrolytic rather than oxidative, since it contains no cysteine, methionine, or tryptophan residues. The aspartate–glycine step is a recognised site for aspartimide formation under mildly acidic or basic conditions, generating isoaspartate and succinimide-related products over time. Desiccated lyophilised powder held at −20 °C is comparatively stable, whereas dilute solutions degrade faster and are best frozen as single-use aliquots rather than thawed repeatedly.
No pharmacopoeial monograph exists for this peptide, so quality rests on the supplier's internal specifications and on whatever independent testing a purchaser arranges. Certificates of analysis differ widely in which tests they report and in the limits applied. The counter-ion introduced during purification, commonly acetate or trifluoroacetate, changes the net peptide content of a given mass of powder, so two samples of equal weight may not contain equal amounts of the active sequence. Third-party laboratories can verify purity, identity, residual solvents, and counter-ion content for a fee, which makes documentation more informative than labelling.
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February 23, 2011 Venezuela Economists expressed concern with regards to Venezuela's economy improving due to instability in the private sector pressured by the socialist government, as José Guerra, former manager at the Central Bank of Venezuela, stated that private investment, accounting for half of Venezuela's GDP, dropped 2.2% in 2010.
Although most of its ecological habitats are still intact, there is an increasing population with industrial and tourism development. This is putting more pressure on the vegetation through the process of logging, overgrazing, woodcutting and infrastructure of development plans. Though the tree is widespread, it has become fragmented with the development that has occurred in its habitats. Many of its populations are suffering poor regeneration. Human activities have greatly reduced the population through overgrazing, and feeding the flowers and fruits to the livestock of the island. One of the greatest threats is the gradual drying out of the Socotra Archipelago, which has been an ongoing process for the last few hundred years. This has resulted in non-flourishing trees, and the duration of the mist and cloud around the area seems to also be decreasing. Increasingly arid environments are predicted to cause a 45 percent reduction in the available habitat for D. cinnabari by 2080. Another threat comes from goat grazing in the area, which prevents regeneration and prevents seedlings developing in locations other than rocky outcrops. Additional threats include harvesting of its resin and use of its leaves as fodder during the dry season. Presently some trees have been used to make beehives. This was generally prohibited; this displays how the species may be threatened by a breakdown in the traditional practices of the island. The best preserved and largest stand of D. cinnabari is on the limestone plateau named Rokeb di Firmihin.
Sources: en.wikipedia.org
Churchill is a man with an out-of-date political idea—that of the European balance of power. It no longer belongs to the sphere of realities. And yet it's because of this superstition that Churchill stirred England up to war. On another occasion he added: Without the Wehrmacht, a "wave would have swept over Europe that would have taken no care of the ridiculous British idea of the balance of power in Europe in all its banality and stupid tradition—once and for all." In fact, Churchill shortly adopted a similar view: Our Russian friends and Allies, he spoke in 1946, most admire strength and least respect military weakness. "For that reason the old doctrine of a balance of power is unsound. We cannot afford … to work on narrow margins, offering temptations to a trial of strength." If the Western Democracies do not stand together "then indeed catastrophe may overwhelm us all." If, however, "the population of the English-speaking Commonwealths be added to that of the United States with all that such co-operation implies in the air, on the sea, all over the globe and in science and in industry, and in moral force, there will be no quivering, precarious balance of power to offer its temptation to ambition or adventure. On the contrary, there will be an overwhelming assurance of security."
== External links == Overview of all the structural information available in the PDB for UniProt: P06241 (Human Tyrosine-protein kinase Fyn) at the PDBe-KB. Overview of all the structural information available in the PDB for UniProt: P39688 (Mouse Tyrosine-protein kinase Fyn) at the PDBe-KB.
==== Hybrid Closed Loop (HCL) / Advanced Hybrid Closed Loop (AHCL) ==== Hybrid closed loop (HCL) systems further expand on the capabilities of PLGS systems by adjusting basal insulin delivery rates both up and down in response to values from a continuous glucose monitor. Through this modulation of basal insulin, the system is able to reduce the magnitude and duration both hyperglycemic and hypoglycemic events. Users still must initiate manual mealtime boluses. Advanced hybrid closed loop systems have advanced algorithms. Fully Closed Loop (FCL) Fully or full closed loop (FCL) systems adjust insulin delivery in response to changes in glucose levels without requiring input by users for mealtime insulin or announcements of meals.
Sources: en.wikipedia.org
=== First World Cup appearance (1958–1962) === Colombia entered World Cup qualifying for the first time in 1961, meeting Peru over two legs under Argentine manager Pedernera, who had remained in the country after El Dorado as a coach. A 1–0 win in Bogotá on 30 April 1961 was followed by a 1–1 draw in Lima a week later, and Colombia advanced to the 1962 FIFA World Cup in Chile. Drawn in Group 1 with Uruguay, the Soviet Union and Yugoslavia, Colombia lost their opening match to Uruguay 2–1 on 30 May and were beaten 5–0 by Yugoslavia on 7 June, finishing bottom of the group with a single point from three games and five goals scored against eleven conceded. Their remaining fixture, however, produced one of the tournament's defining results. Facing the reigning European champions at the Estadio Carlos Dittborn in Arica on 3 June before a crowd of 8,040, with Brazilian referee João Filho officiating, Colombia trailed 3–0 inside eleven minutes to goals from Valentin Ivanov in the eighth and eleventh minutes either side of an Igor Chislenko strike in the tenth. Germán Aceros reduced the deficit in the 21st minute, but Viktor Ponedelnik restored a three-goal lead in the 56th. With twenty minutes remaining, Marcos Coll scored directly from a corner in the 68th minute, the ball creeping in at the near post past Lev Yashin — the only goal scored direct from a corner in World Cup history, and conceded by a goalkeeper then widely regarded as the world's finest. Antonio Rada struck in the 72nd minute and Marino Klinger completed the recovery late on to secure a 4–4 draw.
== Genetics and strains == Mice are mammals of the clade (a group consisting of an ancestor and all its descendants) Euarchontoglires, which means they are amongst the closest non-primate relatives of humans along with lagomorphs, treeshrews, and flying lemurs.
In a ranking of cities by safety that was prepared by The Economist newspaper in 2021, Moscow was ranked 38th with a score of 62.5 points. The general level of crime is low. More than 170,000 surveillance cameras in Moscow are connected to a facial recognition system. The authorities approved of a two-month experiment with automatic, real-time recognition of faces, gender, and age of people; so these authorities deployed the system around the entire city. A video surveillance network integrates video cameras in 95% of the city's apartment buildings; on the grounds and inside buildings of schools and kindergartens; and in MCC stations, stadiums, public transit stops, bus stations, parks, and underground passages. Moscow's emergency numbers match those in all other regions of Russia:
=== Ammonia solutions === The alkali metals dissolve slowly in liquid ammonia, forming ammoniacal solutions of solvated metal cation M+ and solvated electron e−, which react to form hydrogen gas and the alkali metal amide (MNH2, where M represents an alkali metal): this was first noted by Humphry Davy in 1809 and rediscovered by W. Weyl in 1864. The process may be speeded up by a catalyst. Similar solutions are formed by the heavy divalent alkaline earth metals calcium, strontium, barium, as well as the divalent lanthanides, europium and ytterbium. The amide salt is quite insoluble and readily precipitates out of solution, leaving intensely coloured ammonia solutions of the alkali metals. In 1907, Charles A. Kraus identified the colour as being due to the presence of solvated electrons, which contribute to the high electrical conductivity of these solutions. At low concentrations (below 3 M), the solution is dark blue and has ten times the conductivity of aqueous sodium chloride; at higher concentrations (above 3 M), the solution is copper-coloured and has approximately the conductivity of liquid metals like mercury. In addition to the alkali metal amide salt and solvated electrons, such ammonia solutions also contain the alkali metal cation (M+), the neutral alkali metal atom (M), diatomic alkali metal molecules (M2) and alkali metal anions (M−). These are unstable and eventually become the more thermodynamically stable alkali metal amide and hydrogen gas. Solvated electrons are powerful reducing agents and are often used in chemical synthesis.
Sources: en.wikipedia.org
It is a synthetic tetrapeptide built from alanine, glutamate, aspartate and glycine. The four residues are joined by standard peptide bonds, giving a linear chain rather than a branched structure.
The name derives from epithalamin, a pineal gland extract studied in the former Soviet Union. Researchers proposed that short fragments of that extract carried the biological activity of interest.
No major regulatory agency has approved it as a medicine. It is handled as a research chemical, and products sold under this name are not standardised drugs with defined clinical labelling.
Sealed lyophilised powder is normally kept at minus twenty degrees Celsius or below, away from light and moisture. Vials are allowed to reach room temperature before opening to limit condensation. Repeated warming and cooling of the same vial is discouraged.