Everything below concerns pineal peptides. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2026-01-26. Numbers and descriptions here follow the published literature rather than marketing material.
Epitalon is a synthetic tetrapeptide with the residue sequence alanine-glutamate-aspartate-glycine, commonly abbreviated AEDG. Its monoisotopic mass is approximately 390.35 daltons, and it is usually supplied as a lyophilised trifluoroacetate or acetate salt. The compound was derived from a pineal gland extract called epithalamin, a heterogeneous preparation investigated in the former Soviet Union. Researchers associated with the Saint Petersburg Institute of Bioregulation and Gerontology described the tetrapeptide as a constituent fragment of that extract. Commercial material is offered as a laboratory reagent rather than as a finished pharmaceutical product.
Literature searches for this compound must account for several spelling variants. Indexing databases contain epitalon, epithalon, epithalone, and AEDG, and relevant records are scattered across Russian-language and English-language journals that do not consistently cross-cite. Early publications describe the parent extract as a mixture of many peptides, whereas later work addresses the single synthetic tetrapeptide. That shift in nomenclature complicates comparison between studies, because extract data and tetrapeptide data are sometimes cited interchangeably. A search strategy omitting the alternate spellings will return an incomplete set of references.
Reversed-phase high-performance liquid chromatography is the standard approach for assessing purity, usually with ultraviolet detection near 214 nm, where the peptide bond absorbs. Mass spectrometry, most often with electrospray ionization, confirms the molecular mass and helps reveal truncation or deletion byproducts. Amino acid analysis can verify composition, and counterion content is sometimes measured because peptides purified with trifluoroacetic acid retain variable amounts of that salt. Purity figures reported without a stated method and detection wavelength are difficult to interpret.
Material sold for research use varies widely in documented quality. A useful verification package includes a certificate of analysis that states peptide content rather than only net weight, the chromatographic method and column used, and a mass spectrum consistent with the expected mass. Independent testing by a third-party laboratory is occasionally reported. Statements of identity resting only on a supplier label provide little assurance, and the gap between nominal mass and actual peptide content can be substantial once counterions and residual water are counted.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic tetrapeptide | Four amino acid residues |
| Residue sequence | Ala-Glu-Asp-Gly | Abbreviated AEDG |
| Approximate mass | 390.35 Da | Monoisotopic, free base form |
| Parent preparation | Epithalamin extract | Derived from pineal tissue |
| Common spelling variants | Epithalon, epithalone, AEDG | Affects literature retrieval |
Laboratory work has examined effects on telomerase activity in cultured cells, on melatonin rhythms in animals, and on markers of oxidative stress. Some experiments report measurable changes while others show none, and the reported findings rest largely on small studies. The absence of large independent trials means the generality of these results is unresolved rather than settled. Review articles occasionally apply the label geroprotector, a term that reflects a research hypothesis about ageing rather than an established clinical finding.
Epitalon is the common name for a synthetic tetrapeptide with the sequence alanine-glutamate-aspartate-glycine, usually abbreviated AEDG. All four residues are proteinogenic amino acids, and the free peptide has a calculated mass near 390 grams per mole. Because the chain is short and carries no modifications, it is assembled readily by solid-phase synthesis and is distributed mainly as a freeze-dried solid for laboratory work. Catalogue listings use the spellings epitalon, epithalone, and simply AEDG, and the three refer to the same sequence.
Verification of research-grade material involves comparing a supplier chromatogram against an in-house reference, checking the observed mass against the calculated value, and where possible confirming residue order by tandem mass spectrometry or enzymatic peptide mapping. Purity claims should be read alongside the method used to obtain them, because detection wavelength and integration settings alter the result. Batch-specific data, rather than a generic grade statement, is the informative part of a certificate.
Identity and purity of epitalon samples are normally established by reversed-phase high-performance liquid chromatography with ultraviolet detection near 214 nanometres, combined with mass spectrometry. The mass spectrum confirms the expected molecular ion and can reveal truncated or oxidised by-products. Amino acid analysis after acid hydrolysis verifies that the four residues are present in the expected ratio. Certificates typically report a purity figure taken from chromatographic peak area, expressed as a percentage of total integrated signal.
The published literature is dominated by a small number of research groups, much of it in Russian-language journals, and independent replication outside those groups is limited. Studies are typically small, use cultured cells or rodent models, and report endpoints that differ between papers, which makes comparison difficult. Large randomised human trials have not appeared in the indexed literature. Questions about absorption, distribution and clearance are therefore still treated as open in reviews that mention the compound.
Epitalon is a synthetic tetrapeptide with the sequence alanine–glutamate–aspartate–glycine, commonly abbreviated AEDG. Its design traces to epithalamin, a peptide fraction prepared from bovine pineal gland extracts that researchers in Saint Petersburg began investigating in the 1970s. The compound has a molecular formula of C14H22N4O9 and a nominal molecular mass near 390 daltons. It holds no approved drug status in the United States or the European Union, and material sold under this name is generally offered as a research chemical rather than a finished pharmaceutical product.
Proposed mechanisms centre on cell-culture observations rather than a defined receptor interaction. Several reports describe increased expression of the telomerase catalytic subunit after exposure of cultured human cells, and the authors attributed the effect to short peptide fragments entering the nucleus and influencing gene transcription. No receptor for the tetrapeptide has been identified, and the free peptide is expected to be degraded rapidly by plasma peptidases. Whether any measurable fraction reaches intact tissues after administration remains an unresolved question rather than an established finding.
Epitalon appears in the literature primarily through a small number of research groups, most of them associated with the St. Petersburg Institute of Bioregulation and Gerontology. Publications describe cell culture experiments, animal studies, and a limited number of small human studies. Independent replication outside this network is sparse. As a result, reviews of the topic usually separate descriptive reports of observed effects from the question of whether those effects generalize, and they note the difficulty of comparing studies that use different preparations and endpoints.
Analytical characterization of epitalon relies on standard peptide methods. Reverse-phase high-performance liquid chromatography is used to assess purity, and mass spectrometry confirms identity by checking the observed mass against the expected value near 390 daltons. Amino acid analysis can verify composition. Because the peptide is short and hydrophilic, it elutes early on many reverse-phase columns, so method development often requires ion-pairing reagents to achieve adequate retention and resolution from related impurities.
Storage and handling follow conventional peptide practice. Lyophilized epitalon is typically kept refrigerated or frozen, protected from moisture and light, and allowed to equilibrate to room temperature before opening to avoid condensation. Once dissolved, aqueous solutions are usually stored cold and used within a short period, since dilute peptide solutions can support microbial growth and may slowly degrade. The absence of cysteine and methionine reduces, but does not eliminate, oxidation concerns during long-term storage.
Judges in Singapore were given a discretion to impose a sentence of life imprisonment with mandatory caning for offenders who commit murder but without the intention to kill, which come under Sections 300(b), 300(c) and 300(d) of the Penal Code. The death penalty remains mandatory only for murders committed with the intention to kill, which come under section 300(a) of the Penal Code. Provided that drug traffickers only act as couriers, suffer from impaired mental responsibility (e.g. depression), or substantively assist the authorities in tackling drug trafficking activities, among other conditions, judges also had the discretion to impose life sentences instead of death. Drug traffickers who were not condemned to death but to life-long incarceration with caning would receive at least 15 strokes of the cane, unless suffering from mental incapacity. Despite this discretion, a sentence of life imprisonment is the mandatory minimum penalty for capital murder or drug trafficking offences. The first person to be sentenced to life imprisonment, instead of receiving the death penalty, under the amended death penalty laws was drug trafficker Abdul Haleem bin Abdul Karim on 10 April 2013, having been a courier in traffic drugs and had assisted the authorities in disrupting the drug trafficking activities. In addition to his life sentence, Abdul Haleem, who pleaded guilty to two charges of drug trafficking, was also given the maximum sentence of 24 strokes of the cane.
Manual: Healthcare providers or clinical trial coordinators manually review patient records and available trial criteria to identify potential matches. This might also include manually searching in clinical trial databases. Electronic health records (EHR). Some systems integrate with EHRs to automatically flag patients that may be eligible for trials based on their medical data. These systems may leverage machine learning, artificial intelligence or precision medicine methods to more effectively match patients to trials. These methods are faced with the challenge of overcoming the limitations of EHR records such as omissions and logging errors. Direct-to-patient services: Resources are specialized to support patients in finding clinical trials through online platforms, hotlines, and personalized support.
By stabilizing the transition state: Creating an environment with a charge distribution complementary to that of the transition state to lower its energy By providing an alternative reaction pathway: Temporarily reacting with the substrate, forming a covalent intermediate to provide a lower energy transition state By destabilizing the substrate ground state: Distorting bound substrate(s) into their transition state form to reduce the energy required to reach the transition state By orienting the substrates into a productive arrangement to reduce the reaction entropy change (the contribution of this mechanism to catalysis is relatively small) Enzymes may use several of these mechanisms simultaneously. For example, proteases such as trypsin perform covalent catalysis using a catalytic triad, stabilize charge build-up on the transition states using an oxyanion hole, complete hydrolysis using an oriented water substrate.
Men may also suffer from body dysmorphic disorder (BDD), and specifically penile dysmorphic disorder (PDD). In one study, 54% of men with Peyronie's disease overestimated their degree of penile curvature, with 44% of men overestimating their degree of penile curvature by more than 20°. Only 20% of men accurately estimated their degree of curvature within 5°. Body dysmorphic disorder (BDD) is a condition defined by an overwhelming preoccupation with a perceived flaw in one's physical appearance. Its importance is disproportionately magnified in the mind of the individual. Ruminations concerning this perceived defect become pervasive and intrusive, consuming substantial mental bandwidth for extended periods each day. This excessive preoccupation induces severe emotional distress and also disrupts daily functioning and activities. The DSM-5 places BDD within the obsessive–compulsive spectrum, distinguishing it from disorders such as anorexia nervosa. Penile dysmorphic disorder (PDD) is a manifestation of body dysmorphic disorder where the main area of fixation is the penis. Individuals with penile dysmorphic disorder typically develop heightened anxiety, shame, and dissatisfaction about their penis. This distorted perception may interfere with daily functioning and relationships. Although penile dysmorphic disorder is not formally classified as a distinct diagnosis, it has become more prominent in clinical studies and discussions around male body image.
Sources: en.wikipedia.org
Rodrigo Roa Duterte (born March 28, 1945) is a Filipino former politician who served as the 16th president of the Philippines from 2016 to 2022. He served as mayor of Davao City for three non-consecutive terms between 1988 and 2016. Duterte is the first Philippine president from Mindanao, and the oldest person to assume office, beginning his term at age 71. Duterte is the chairman of PDP–Laban, the ruling party during his presidency. Born in Maasin, Leyte (now in Southern Leyte), Duterte moved to Davao as a child where his father, Vicente Duterte, served as provincial governor. He studied political science at the Lyceum of the Philippines University, graduating in 1968, before obtaining a law degree from San Beda College of Law in 1972. He then worked as a lawyer and prosecutor for Davao City, before becoming vice mayor and, subsequently, mayor of the city in the wake of the 1986 People Power Revolution. Duterte won seven terms and served as mayor of Davao for over 22 years, during which the once crime-ridden city became peaceful and investor-friendly. Duterte's 2016 presidential campaign led to his election victory. During his presidency, his domestic policy focused on combating the illegal drug trade by initiating the controversial war on drugs, fighting crime and corruption, and intensified efforts against terrorism and communist insurgency. He launched a massive infrastructure plan, initiated liberal economic reforms, streamlined government processes, and proposed a shift to a federal system of government which was ultimately unsuccessful.
In January 2020, the United States Army and Navy banned TikTok on government devices after the Defense Department labeled it a security risk. Recruiters had been using the app to help fill quotas, and some continue to maintain a level of engagement through their personal accounts. According to a 2020 article in The New York Times, Central Intelligence Agency analysts determined that while it is possible the Chinese government could obtain user information from the app, there was no evidence it had done so.
== Exploration of L-Threonine for Tuberculosis == With multidrug-resistant Mycobacterium tuberculosis (TB) remaining a public health crisis with a total of 1.25 million people dead worldwide from TB in 2023 alone, new treatment strategies for TB are critical. TB is an airborne infection, spread via inhalation of airborne droplets that can remain suspended in the air for several hours, and can either be killed, remain in a latent stage, or become active. One previous paper researched the inhibitory effects of the downstream product L-threonine on the homoserine kinase (HSK) pathway in Escherichia coli. They found that the HSK pathway can be successfully inhibited via L-threonine since the pathway acts as a negative feedback loop, becoming inhibited once enough of the product is formed. Investigation of this pathway in TB may yield new insights into potential drug targets. Inhibiting the fatty acid synthesis pathway as well could serve as a potential drug target since this pathway is responsible for synthesizing mycolic acids, components necessary for formation of TB's cell walls. Coupling of the amino acid L-threonine with a common TB drug that inhibits fatty acid synthesis, like ethionamide, could yield a new treatment strategy for tuberculosis.
=== 1H—13C HSQC === This experiment provides correlations between a carbon and its attached protons. The constant time (CT) version of 1H—13C HSQC is normally used as it circumvents the issue of splitting of signal due to homonuclear 13C—13C J couplings which reduces spectral resolution. The "constant time" refers to the entire evolution period between the two INEPT steps which is kept constant in this experiment. If this evolution period is set to be the inverse of the J-coupling constant, then the sign of the magnetization of those carbons with an odd number of aliphatic carbon attached will be opposite to those with an even number. For example, if the Cβ of leucine appears as a positive peak (2 aliphatic carbons attached), then the Cγ (3 aliphatic carbons attached) and Cα (1 aliphatic carbons attached) would appear negative.
== Pharmacokinetics == Icodextrin is not significantly metabolised inside the peritoneum. Instead, it is absorbed slowly (40% after 12 hours) into the bloodstream via the lymph vessels. There it is broken down into oligosaccharides by the enzyme alpha-amylase. In patients with intact kidney function, both icodextrin and its fragments are excreted via the kidney by glomerular filtration.
Sources: en.wikipedia.org
Note that most commonly used lac or lac-derived promoters are based on the lacUV5 mutant which is insensitive to catabolite repression. This mutant allows for expression of protein under the control of the lac promoter when the growth medium contains glucose since glucose would inhibit gene expression if wild-type lac promoter is used. Presence of glucose nevertheless may still be used to reduce background expression through residual inhibition in some systems. Examples of E. coli expression vectors are the pGEX series of vectors where glutathione S-transferase is used as a fusion partner and gene expression is under the control of the tac promoter, and the pET series of vectors which uses a T7 promoter. It is possible to simultaneously express two or more different proteins in E. coli using different plasmids. However, when 2 or more plasmids are used, each plasmid needs to use a different antibiotic selection as well as a different origin of replication, otherwise one of the plasmids may not be stably maintained. Many commonly used plasmids are based on the ColE1 replicon and are therefore incompatible with each other; in order for a ColE1-based plasmid to coexist with another in the same cell, the other would need to be of a different replicon, e.g. a p15A replicon-based plasmid such as the pACYC series of plasmids. Another approach would be to use a single two-cistron vector or design the coding sequences in tandem as a bi- or poly-cistronic construct.
=== Death === De Duve died on 4 May 2013, at his home in Nethen, Belgium, aged 95. He decided to end his life by legal euthanasia, performed by two doctors and in the presence of his four children. He had been long suffering from cancer and atrial fibrillation, and his health problems were exacerbated by a recent fall in his home. De Duve was cremated as he had willed, and his ashes were distributed among family members and friends.
Prominent figures included ethnic Mongol general Ulanhu, who served in high-ranking roles in the Inner Mongolian region and as vice president of China, and Saifuddin Azizi, a Lieutenant General and an ethnic Uyghur who served in the CCP Central Committee. There were a few instances of ethnic distrust within the PLA, with one prominent example being the defection of Margub Iskhakov, an ethnic Muslim Tatar PLA general, to the Soviet Union in the 1960s. However, his defection largely contributed to his disillusion with the failed Great Leap Forward policies, instead of his ethnic background. In modern times, ethnic representation is most visible among junior-ranking officers. Only a few minorities reach the highest-ranking positions.
Cephalopods are a diverse group of species, but share common life history traits, for example, they have a rapid growth rate and short life spans. Stearns (1992) suggested that in order to produce the largest possible number of viable offspring, spawning events depend on the ecological environmental factors of the organism. The majority of cephalopods do not provide parental care to their offspring, except, for example, octopus, which helps this organism increase the survival rate of their offspring. Marine species' life cycles are affected by various environmental conditions. The development of a cephalopod embryo can be greatly affected by temperature, oxygen saturation, pollution, light intensity, and salinity. These factors are important to the rate of embryonic development and the success of hatching of the embryos. Food availability also plays an important role in the reproductive cycle of cephalopods. A limitation of food influences the timing of spawning along with their function and growth. Spawning time and spawning vary among marine species; it's correlated with temperature, though cephalopods in shallow water spawn in cold months so that the offspring would hatch at warmer temperatures. Breeding can last from several days to a month.
One prominent general, Alexios I, usurped the throne in 1081. In contrast to the prior turmoil, the three reigns of Alexios (r. 1081–1118), his son John II (r. 1118–1143), and his grandson Manuel I (r. 1143–1180) lasted almost a century and restored the empire's regional authority for the final time. Alexios immediately faced the Normans under Robert Guiscard and repelled them through warfare and diplomacy. He then targeted the Pechenegs and decisively defeated them in 1091 with help from the Cumans; a separate Cuman incursion followed in 1094. Finally, looking to recover Asia Minor from the Seljuks, he approached Pope Urban II for help c. 1095. The scale and aims of western Christendom's response exceeded Byzantine expectations: the First Crusade helped restore parts of western Anatolia to Byzantine control, although Alexios and its leaders soon fell out. The rest of his reign was spent dealing with the Normans and Seljuks, establishing a new, loyal aristocracy to ensure stability, and carrying out fiscal and ecclesiastical reforms.
Sources: en.wikipedia.org
It is based on epithalamin, a peptide-rich preparation obtained from pineal gland tissue and studied in the former Soviet Union. Researchers later identified the tetrapeptide AEDG as a constituent fragment of that material. Modern supplies are produced by chemical synthesis rather than tissue extraction.
No. Epithalamin is a heterogeneous extract containing many peptides, while epitalon is a single synthesised tetrapeptide. Publications sometimes treat findings from the two as equivalent, which is a common source of confusion. Their compositions differ and they are not interchangeable in analytical terms.
Most published work uses cell cultures or rodents because those models are faster and less costly to run. The few human trials that have been reported are small, and several lack control groups or blinding. This restricts what can reasonably be concluded about effects in people.
The powder is normally kept at −20 °C or below in a sealed, moisture-protected container. Letting the vial reach room temperature before opening helps prevent condensation on the contents.