Research chemical 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 2026-01-30. Numbers and descriptions here follow the published literature rather than marketing material.
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.
The compound is generally presented as a synthetic fragment of epithalamin, a pineal gland extract investigated in the former Soviet Union from the 1970s onward. Vladimir Khavinson and colleagues in Saint Petersburg developed short peptides modelled on such extracts, and epitalon became the most widely cited of those sequences. Most primary reports appeared in Russian-language journals or in proceedings with limited international circulation. Independent replication in laboratories outside that network remains sparse, and much repeated secondary material traces back to a small number of originating groups.
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.
Identity and purity are checked by reversed-phase high-performance liquid chromatography, usually with ultraviolet detection near 214 nanometres, where the peptide bond absorbs. Mass spectrometry confirms the expected mass and reveals whether truncation products or adducts are present. Acid hydrolysis followed by amino acid analysis gives the residue ratio, which should approximate one alanine, one glutamate, one aspartate and one glycine. Counter-ions such as acetate or trifluoroacetate remain in the dried product and lower net peptide content, so a stated purity figure on a label does not by itself describe how much peptide a vial holds.
Regulatory treatment differs by country. No formulation of epitalon holds a marketing authorisation as a medicine in the United States or the European Union, where material sold for laboratory use is handled as a research chemical and is not intended for human consumption. In Russia, several short peptide preparations from the same institute's peptide series are registered medicinal products, and epitalon appears in that national context. Elsewhere it is frequently offered as a cosmetic ingredient, a category with lighter requirements. Advertising claims about longevity or disease prevention are restricted in most jurisdictions, which limits how sellers describe the compound.
Freeze-dried epitalon is normally kept at minus twenty degrees Celsius in a sealed, desiccated container, protected from light. Short excursions at ambient temperature during shipping are generally tolerated, but repeated warming and cooling cycles encourage moisture uptake, which shortens shelf life. Once dissolved, the peptide is far less stable than the solid: aqueous solutions are subject to hydrolysis and to deamidation at the aspartate and glutamate residues. Working solutions are therefore held refrigerated and used within days, and repeated freezing and thawing of the same vial is best avoided.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C14H22N4O9 | Computed for the free acid of Ala-Glu-Asp-Gly |
| Molecular mass | About 390.35 g/mol | Free peptide; salt forms shift the value |
| Appearance | White to off-white solid | Typical of short peptides after freeze-drying |
| Solubility class | Freely soluble in water | Aqueous buffers are also commonly used |
| Common synonyms | Epitalon, epithalone, AEDG | AEDG is the single-letter sequence |
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.
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.
The most widely cited claim is that epitalon activates telomerase and thereby extends telomere length. Supporting evidence comes largely from cultured human cells, where treatment was associated with increased telomerase activity and delayed replicative senescence. Telomerase activation is a biologically consequential effect, since the enzyme is largely silenced in most somatic cells. However, the route by which a short peptide would reach and act on the enzyme's regulatory machinery has not been established. Independent replication in human trials is scarce, so the link between cell-culture observations and whole-body aging remains an open question.
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.
De Duve won the Francqui Prize for Biological and Medical Sciences in 1960, and the Nobel Prize for Physiology or Medicine in 1974. King Baudouin of Belgium honoured him to Viscount in 1989. He was the recipient of the Gairdner Foundation International Award in 1967, and the Dr H.P. Heineken Prize for Biochemistry and Biophysics in 1973 from the Royal Netherlands Academy of Arts and Sciences. He was elected a foreign associate of the National Academy of Sciences (United States) in 1975. He won the Harden Medal of the Biochemical Society of Great Britain in 1978; the Theobald Smith Award from the Albany Medical College in 1981; the Jimenez Diaz Award in 1985; the Innovators of Biochemistry Award from Medical College of Virginia in 1986; and the E.B. Wilson Medal in 1989. He was also a member of the Royal Academies of Medicine and the Royal Academy of Sciences, Arts, and of Literature of Belgium; the Pontifical Academy of Sciences of the Vatican; the American Academy of Arts and Sciences; the French National Academy of Medicine; the Academy of Sciences of Paris; the Deutsche Akademie der Naturforscher Leopoldina; the American Philosophical Society. He was elected a Foreign Member of the Royal Society (ForMemRS) in 1988. In addition, he received honorary doctorates from eighteen universities around the world.
== Causes == Lymphocytosis is a feature of infection, particularly in children. In the elderly, lymphoproliferative disorders, including chronic lymphocytic leukemia and lymphomas, often present with lymphadenopathy and a lymphocytosis. Causes of absolute lymphocytosis include:
Screening athletes for cardiac disease can be problematic because of low prevalence and inconclusive performance of various tests that have been used. Nevertheless, sudden death among seemingly healthy individuals attracts much public and legislator attention because of its visible and tragic nature. As an example, the Texas Legislature appropriated US$1 million for a pilot study of statewide athlete screening in 2007. The study employed a combination of questionnaire, examination and electrocardiography for 2,506 student athletes, followed by echocardiography for 2,051 of them, including any students with abnormal findings from the first three steps. The questionnaire alone flagged 35% of the students as potentially at risk, but there were many false positive results, with actual disease being confirmed in less than 2%. Further, a substantial number of screen-positive students declined repeated recommendations for follow-up evaluation. (Individuals who are conclusively diagnosed with cardiac disease are usually told to avoid competitive sports.) It should be stressed that this was a single pilot program, but it was indicative of the problems associated with large-scale screening, and consistent with experience in other locations with low prevalence of sudden death in athletes.
In Korea, lotus flower tea (Korean: 연꽃차; RR: yeonkkotcha) is made from the dried petals of the white lotus. The stamens can be dried and made into a fragrant herbal tea (Chinese: 蓮花 茶; pinyin: liánhuā cha; Cantonese Yale: lìhnfāa chah), or used to impart a scent to tea leaves (particularly in Vietnam). This Vietnamese lotus tea is called trà sen, chè sen, or chè ướp sen.
Sources: en.wikipedia.org
=== Breast cancer === Keratin constitutes a large multigene family known as cytokeratins. These cytokeratins are differentially expressed across various epithelial types and have been extensively studied as markers for breast cancer. They are categorized into acidic type I and basic-to-neutral type II cytokeratins. The intermediate filament network is formed by the necessary pairing of equal amounts of type I and type II keratins. While hair keratins, such as KRT81, are typical in hard-keratinized structures like hair and nails, they are thought to serve as structural proteins specific to these organs without expression elsewhere, such as the mammary gland. KRT81, a type II hair keratin, is a major hair protein expressed in the hair cortex. Despite being typically associated with hair structures, KRT81 expression has been observed in the SKBR3 human breast cancer cell line and metastatic lymph nodes of breast carcinomas, but not in normal breast epithelial cells. Moreover, the expressed KRT81 was found to be a 5′-truncated isoform (ΔHb1), with the full-length protein not being expressed. However, the exact function of this truncated form in breast cancer cells remains unclear. Western blot analysis detected the presence of the complete 55-kDa KRT81 in various human breast cancer cell lines (MCF7, SKBR3, MDA-MB-231), normal human mammary epithelial cells (HMEC), and non-neoplastic cells (MCF10A). Reverse transcription-polymerase chain reaction confirmed the expression of the full-length KRT81, encompassing its 5' region, in breast cells.
Further shell closures beyond the main island of stability in the vicinity of Z = 112–114 may give rise to additional islands of stability. Although predictions for the location of the next magic numbers vary considerably, two significant islands are thought to exist around heavier doubly magic nuclei; the first near 354126 (with 228 neutrons) and the second near 472164 or 482164 (with 308 or 318 neutrons). Nuclides within these two islands of stability might be especially resistant to spontaneous fission and have alpha decay half-lives measurable in years, thus having comparable stability to elements in the vicinity of flerovium. Other regions of relative stability may also appear with weaker proton shell closures in beta-stable nuclides; such possibilities include regions near 342126 and 462154. Substantially greater electromagnetic repulsion between protons in such heavy nuclei may greatly reduce their stability, and possibly restrict their existence to localized islands in the vicinity of shell effects. This may have the consequence of isolating these islands from the main chart of nuclides, as intermediate nuclides and perhaps elements in a "sea of instability" would rapidly undergo fission and essentially be nonexistent. It is also possible that beyond a region of relative stability around element 126, heavier nuclei would lie beyond a fission threshold given by the liquid drop model and thus undergo fission with very short lifetimes, rendering them essentially nonexistent even in the vicinity of greater magic numbers.
During 1973–2013, Khavinson et al., extracted from various organs over 20 complexes of physiologically active peptides, as well as 15 others synthesized from amino acids, (di-, tri-, tetrapeptides), all being covered by patents in many countries including the US, Canada, Australia, Europe, Japan, Korea, Israel, etc. After many years of experimental and clinical studies, six medicinal peptide preparations were permitted for medical use in the USSR, Russia, and afterward in the CIS countries. They were primarily to be used by the military medical service. These are ‘Thymalin’- a preparation of the thymus, being a cellular immunity regulator; ‘Epithalamin’ — a preparation from the pineal gland — regulator of the endocrine system, which restores melatonin, (with no analogues worldwide) ‘Cortexin’ — a preparation from the cerebral cortex, brain function regulator; ‘Prostatilen’ or ‘Samprost’ or ‘Vitaprost’ — a preparation from the prostate gland, regulator of prostate function; ‘Retinalamin’ — a preparation from the retina, partially restores functions of the retina in case of laser lesions and degenerative diseases, has no analogues worldwide; ‘Thymogen’ — a dipeptide EW, being first extracted from ‘Thymalin’, then synthesized from amino acids, regulates immunity. These medicinal peptide preparations were first used to restore immune functions of the brain, endocrine system, retina, etc.
The MiniMed 780G is an insulin pump manufactured by Medtronic for patients with diabetes mellitus. The pump operates with a single AA battery and uses a piston-plunger pump to infuse a programmed amount of insulin into the patient through a length of tubing. The 780G uses a one-way wireless radio frequency link to receive blood sugar measurements from the patient's continuous glucose monitor. The 780G is capable of automated insulin delivery with a closed-loop control algorithm branded as SmartGuard.
==== Dental care ==== Preventive dental treatment is also necessary (and often overlooked by the patient), as the lack of saliva associated with xerostomia creates an ideal environment for the proliferation of bacteria that cause cavities. Treatments include at-home topical fluoride application to strengthen tooth enamel and frequent teeth cleanings by a dental hygienist. Existing cavities must also be treated, as cavities that extend into the tooth cannot be effectively treated by teeth cleaning alone, and are at a high risk of spreading into the pulp of the tooth, leading to the loss of vitality and need for extraction or root canal therapy. This treatment regimen is the same as for all xerostomia patients, such as those undergoing head and neck radiation therapy, which often damages the salivary glands; these glands are more susceptible to radiation than other body tissues.
Sources: en.wikipedia.org
Female puberty generally occurs between the ages of 9 and 13 and is characterized by ovulation and menstruation; the growth of secondary sex characteristics, such as growth of pubic and underarm hair, breast, uterine and vaginal growth, widening hips and increased height and weight, also occur during puberty. Male puberty sees the further development of the human penis and testicles. The female inner sex organs are the two ovaries, their fallopian tubes, the uterus, and the cervix. At birth there are about 70,000 immature egg cells that degenerate until at puberty there are around 40,000. No more egg cells are produced. Hormones stimulate the beginning of menstruation, and the ongoing menstrual cycles. The female external sex organs are the vulva (labia, clitoris, and vestibule). The male external genitalia include the penis and scrotum that contains the testicles. The testicles are gonads that produce the sperm cells which are ejaculated in semen through the penis. Unlike the egg cells in the female, sperm cells are produced throughout life. Other internal sex organs are the epididymides, vasa deferentia, and some accessory glands. Diseases that affect the reproductive system include polycystic ovary syndrome, a number of disorders of the testicles including testicular torsion, and a number of sexually transmitted infections including syphilis, HIV, chlamydia, HPV and genital warts. Cancer can affect most parts of the reproductive system including the penis, testicles, prostate, ovaries, cervix, vagina, fallopian, uterus and vulva.
Corey Taylor − vocals, guitar on track 17, additional guitar on tracks 4, 8 and 12 James Root − guitar (on all tracks except 18), drums on track 15 Josh Rand − guitar (on all tracks except 18) Shawn Economaki − bass (on all tracks except 17 and 18) Roy Mayorga − drums (on all tracks except 1, 15, 17 and 18) Additional personnel
== Theory == The underlying premise of spectroscopy is that light is made of different wavelengths and that each wavelength corresponds to a different frequency. The importance of spectroscopy is centered around the fact that every element in the periodic table has a unique light spectrum described by the frequencies of light it emits or absorbs consistently appearing in the same part of the electromagnetic spectrum when that light is diffracted. This opened up an entire field of study with anything that contains atoms. Spectroscopy is the key to understanding the atomic properties of all matter. As such spectroscopy opened up many new sub-fields of science yet undiscovered. The idea that each atomic element has its unique spectral signature enabled spectroscopy to be used in a broad number of fields each with a specific goal achieved by different spectroscopic procedures. The National Institute of Standards and Technology maintains a public Atomic Spectra Database that is continually updated with precise measurements. With an absorption spectrophotometer, the level of absorption of a light source is determined by the Beer-Lambert Law:
Weapon No. 2, which underwent something other than normal release from the aircraft, evidenced by the fact that the parachute did not deploy, also had its arming rods extracted, and those components which were given the opportunity to act, did act in the manner expected. Full operation of this weapon was prevented by several things: Impact occurred so soon after separation of the Bisch rods that the timers were not given an opportunity to run down. The Arm/Safe Switch was in the "Safe" condition as the weapon left the aircraft. Another analysis by Sandia engineers in 1961 concluded that while in both weapons the MC-772 Arm/Safe Switch operated "as it was designed to do," the lanyard-controlled safing-pins "cannot be relied upon to prevent initiation of the fuzing sequence" in this kind of accident, and recommended implementing a modification to the weapons "as rapidly as possible" that would prevent the fuze power supply from activating except when live release was intended. A 1969 analysis by Sandia supervisor Parker F. Jones concluded that the Goldsboro accident illustrated that "the Mk 39 Mod 2 bomb did not possess adequate safety for the airborne alert role in the B-52."
Sources: en.wikipedia.org
It is a four-amino-acid peptide with the sequence alanine-glutamate-aspartate-glycine. The chain is unmodified and contains only standard proteinogenic residues, which makes it straightforward to produce by solid-phase synthesis and to characterise by standard peptide methods.
Epitalon and epithalon both circulate, and the difference reflects transliteration of a name coined in Russian-language publications. Reference to the extract it derives from, epithalamin, explains the shared stem. Databases and suppliers are inconsistent, so a search for one spelling alone may miss relevant entries.
No. Epithalamin is a multi-component preparation obtained from pineal tissue, and its exact composition is not fully characterised. Epitalon is a single defined tetrapeptide described as a short synthetic counterpart of that extract, so the two are related in origin but not interchangeable in identity.
The solid is kept cold, dry and dark, typically at minus twenty degrees Celsius, in a sealed container with desiccant. Dissolved material is kept refrigerated and used promptly. Freezing and thawing a solution repeatedly is avoided because it accelerates degradation.