The short version of aspartimide fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-02-12. Anything still debated is marked as such rather than presented as settled.
Verification of a sample usually begins with reversed-phase high-performance liquid chromatography, which resolves the peptide from truncated sequences and other impurities and expresses purity as a percentage of total peak area. Mass spectrometry by electrospray ionisation or matrix-assisted laser desorption supplies an independent check, because the measured mass can be compared against the theoretical value for AEDG. Amino acid analysis or tandem mass spectrometry sequencing can confirm residue order. Each of these methods answers a different question: a purity figure does not establish identity, and an identity match does not establish how much of the material is intact peptide.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Identity confirmation | Electrospray or MALDI mass spectrometry | Observed mass compared with theoretical 390.35 Da |
| Purity specification | 95 percent or greater by RP-HPLC | Common convention for research-grade peptide |
| Counter-ion | Acetate or trifluoroacetate | Affects net peptide content of a weighed sample |
| Solution storage | −80 °C as single-use aliquots | Repeated freeze–thaw cycles accelerate loss |
| Main degradation route | Aspartimide formation at Asp-Gly | Produces isoaspartate and related species |
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.
Storage recommendations center on limiting moisture, heat, and light. The dry powder is generally kept at minus 20 degrees Celsius, and some suppliers recommend minus 80 degrees for long-term archival. Once dissolved, solutions are usually aliquoted and frozen to avoid repeated freeze-thaw cycles, which can promote aggregation or degradation. Aqueous stability depends on pH and concentration, and buffered saline is often preferred over plain water for biological work. Stability data specific to epitalon remain limited, so general peptide-handling practices are applied by analogy rather than from product-specific validation.
Epitalon is a synthetic tetrapeptide with the sequence alanine-glutamate-aspartate-glycine, abbreviated AEDG. Its molecular formula is C14H22N4O9 and its calculated monoisotopic mass is approximately 390.35 daltons. The compound does not occur naturally as a free peptide; it is produced by solid-phase peptide synthesis. Because it contains two acidic residues and no basic residues, the neutral form carries a net negative charge at physiological pH. This charge profile influences how the peptide behaves in solution and during chromatographic analysis.
Laboratory-grade epitalon is typically supplied as a lyophilized powder. Purity is commonly assessed with reverse-phase high-performance liquid chromatography, often paired with mass spectrometry to confirm molecular identity. Amino acid analysis and peptide mapping can provide additional confirmation of sequence. Certificates of analysis for research materials frequently report purity above 95 percent, although the methods behind such figures vary between suppliers. The absence of a pharmacopeial monograph means that no single standardized assay defines the compound, so reported results depend on the analytical protocol chosen.
Typical storage for the lyophilized powder is −20 °C or lower, in a sealed container protected from light and moisture. Hygroscopic material should be allowed to equilibrate to room temperature before the vial is opened, which limits condensation on the contents. Working solutions are commonly divided into single-use aliquots and frozen to avoid repeated freeze-thaw cycles. Dilute solutions are more prone to adsorption onto plastic surfaces and to loss during filtration, so procedures that minimize transfers and use low-binding labware are preferable.
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.
In its supplied form epitalon is a white to off-white powder, usually lyophilized and often hygroscopic. It dissolves readily in water and in aqueous buffers, and it is commonly handled as the acetate or trifluoroacetate salt to improve stability during purification and drying. The amide backbone is labile in aqueous media, so solutions are less durable than the dry solid. Handling notes in the chemical literature therefore emphasize keeping the powder dry, cool and shielded from light until it is dissolved.
Epitalon is a synthetic tetrapeptide whose sequence is alanine-glutamate-aspartate-glycine, written in single-letter code as AEDG. The four residues are joined by three peptide bonds, giving a linear backbone with no branching and no disulfide bridges. Its calculated molecular mass for the free form is approximately 390.3 daltons, a figure that rises when the compound is supplied as an acetate or trifluoroacetate salt. Because the chain is short, the molecule is defined entirely by its residue order rather than by any folded three-dimensional structure.
The compound is described in the literature as a derivative of epithalamin, a preparation obtained from bovine pineal tissue. Work on this peptide family was carried out mainly by a research group in Saint Petersburg beginning in the 1980s, and the substance was later registered for clinical use in Russia under the name Epitalon. Outside that region it is generally treated as a research chemical rather than an approved medicine. Statements about its biological activity rest on a relatively small number of studies, and independent replication remains limited.
The first fully virtual court hearing of a capital case was made via Zoom on 23 April 2020, when the Court of Appeal acquitted 27-year-old Singaporean drug suspect Mohammad Azli Mohammad Salleh and dismissed both his drug charge and his death sentence. There were originally two executions scheduled for drug traffickers Syed Suhail bin Syed Zin and Mohd Fadzir bin Mustaffa on 18 September 2020 and 24 September 2020 respectively, but they were subsequently postponed due to stays of execution granted pending last-minute appeals against the death sentences. As a result, there was no one executed in 2020. Similarly between January and October 2021, no new execution dates were set for the inmates on Singapore's death row, due to the ongoing COVID-19 pandemic and resurgence of community cases. The execution of Nagaenthran K. Dharmalingam was supposed to be carried out on 10 November 2021, but it was postponed due to Nagaenthran contracting COVID-19. The suspension of Nagaenthran's execution in 2021 also led to no executions being carried out in 2021 itself. There were originally two executions of Roslan Bakar and Pausi Jefridin to be carried out on 16 February 2022 and a third execution of Rosman Abdullah on 23 February 2022 before they were postponed due to the men's appeals. Due to the increasing notices of executions being revealed publicly, there were lingering concerns from civil groups and international figures that Singapore might resume executions to accommodate the growing death row inmate population at Changi Prison.
== Salaries == According to the 2022 Medscape Physician Compensation Report, physicians on average earn $339K annually. Primary care physicians earn $260K annually while specialists earned $368K annually. The table below details the average range of salaries for physicians in the US of medical specialties:
==== Distribution ==== Tiagabine is widely distributed through the body. Its volume of distribution is approximately 1 L/kg. The drug readily crosses the blood–brain barrier. The plasma protein binding of tiagabine is 96%, mainly to albumin and α1-acid glycoprotein.
Sources: en.wikipedia.org
== Biography == Born in 1937 in Rome, Mendes Nassi is descended from a line of physicians. His grandfather, Guido Aaron Mendes, directed the Red Cross Hospital in Rome during the 1930s. As Italian Fascist law instituted a regime of prejudice against Jews in Italy, he moved his family to Switzerland to await British permission to enter the territory of Palestine, later to become the state of Israel. These certificates were obtained with the direct intervention of Pope Pius 12th, a classmate and close friend to Guido. The family moved to Gedera in Israel where David’s father, Maor Mendes and his grandfather pioneered the treatment and obliteration of Tuberculosis in Israel. During the 1947–1949 Palestine war the family moved to Ramat Gan, where he graduated from Ohel Shem high school. During his time in Ramat Gan, he practiced fencing and went on to become captain of the Israeli team. He won all national foil competitions in Israel between the years 1955 and 1963. He then joined the army and married his childhood friend, Nili Shmueli. In 1965 David relocated with his family to the United States to continue his training. He remained in New York City until 1975 when he returned to Israel with his wife and two children, Ido and Sharone. His third child, Yonni, was born in Haifa a few years later.
Benzathine benzylpenicillin requires a cold chain and staff who can inject it, and there is a small risk of anaphylaxis. It was also not reliably available during the 2010s; there have been supply shortages. In the 2010s, a single oral dose of azithromycin was shown to be as effective as intramuscular penicillin. Unlike penicillin, there is strong evidence that yaws is evolving antibiotic resistance to azithromycin; there are two known mutations in the bacterium, each of which can cause resistance and make the treatment ineffective. This has threatened eradication efforts. Within 8–10 hours of penicillin treatment, bacteria can no longer be found in lesion biopsies. Primary and secondary lesions usually heal in 2–4 weeks; bone pain may improve within two days. If treated early enough, bone deformities may reverse and heal. Primary and secondary stage lesions may heal completely, but the destructive changes of tertiary yaws are largely irreversible. If lesions do not heal, or RPR test results do not improve, this may indicate treatment failure or re-infection; the treatment is typically repeated. WHO guidelines say that any presumed treatment failures at 4 weeks require macrolide resistance testing.
Murine respirovirus, now Respirovirus muris, formerly Sendai virus (SeV) and previously also known as murine parainfluenza virus type 1 or hemagglutinating virus of Japan (HVJ), is an enveloped, 150–200 nm diameter, negative sense, single-stranded RNA virus of the family Paramyxoviridae. It typically infects rodents and it is not pathogenic for humans or domestic animals. Respirovirus muris is a member of the genus Respirovirus. The virus was isolated in the city of Sendai in Japan in the early 1950s. Since then, it has been actively used in research as a model pathogen. The virus is infectious for many cancer cell lines (see below), and has oncolytic properties demonstrated in animal models and in naturally occurring cancers in animals. Its ability to fuse eukaryotic cells and to form syncytium was used to produce hybridoma cells capable of manufacturing monoclonal antibodies in large quantities. Recent applications of SeV-based vectors include the reprogramming of somatic cells into induced pluripotent stem cells and vaccine creation. For vaccination purpose the Sendai virus-based constructs could be delivered in a form of nasal drops, which may be beneficial in inducing a mucosal immune response. SeV has several features that are important in a vector for a successful vaccine: the virus does not integrate into the host genome, it does not undergo genetic recombination, it replicates only in the cytoplasm without DNA intermediates or a nuclear phase and it does not cause any disease in humans or domestic animals.
== Methods of performing preputioplasty == Preputioplasty may be performed by Z-plasty, also used in reconstructive surgery to loosen constricting scar tissue following traumatic burns. However, Y-plasty and Z-plasty require a degree of surgical sophistication that physicians in general practice may lack. More commonly it simply consists of one or more very short longitudinal incisions which release the stenosis–the constricting ring of tissue—in the foreskin and are closed transversely: [ | ] is closed and sutured as [ — ]. In the alternative to suturing, "[h]aemostasis [has been successfully] performed [in children] with a heated probe using the flame of an alcohol lamp or with bipolar electrodiathermy." Only one incision is shown in Figure 3; if two or more such incisions are made this will prevent a V-shaped indentation at the opening of the foreskin when the penis is not erect. If incisions are placed on the sides of the phimotic ring, the ultimate cosmetic result is better. It is also recommended that the subcutaneous tissue be undermined to ensure a better cosmetic result. The opening of the foreskin is now normally wide enough for the foreskin to be easily retracted. The foreskin is also slightly shorter (by half the length of the longitudinal incisions which are now closed transversely) because the widening of the phimotic ring takes up some foreskin length. Studies from a large cohort in the Indian Subcontinent show a good acceptance and an interest for foreskin preservation when there is no religious indication to remove the foreskin.
Sources: en.wikipedia.org
Applications using this early discover were limited due to naturally low concentrations of this anti-haemophilic factor in blood and plasma and volume constraints in the circulatory system. In 1954, the Government wished to establish a site for increased production of blood products. This followed on from the importance of blood in therapeutic medicine, the need for blood products during the Second World War (particularly the use of albumin) and the formation on 26 September 1946 of the National Blood Transfusion Service. It had also been discovered that a second form of haemophilia (Haemophilia B) existed, which was treatable with blood protein called Factor IX. An agreement was reached between the Government, MRC and the Lister Institute and the Blood Products Laboratory was established with funding from the Ministry of Health. Enlarged facilities for plasma fractionation and freeze-drying were established. During the 1970s and early 1980s it became apparent that Factor VIII products produced at the BPL site (and other products from other companies) may have infected haemophiliacs with life-threatening viruses. Bigger risks to the patient population arose from U.S.imported products, a practice required since the UK was not self-sufficient in plasma products. In 1991 it was renamed the Bio Products Laboratory to reflect the internal market in the National Health Service and in 1993 it became part of the National Blood Authority. BPL began cross-charging NHS hospitals for its products and limited competition in the international blood plasma market was permitted.
Calorie restriction to promote weight loss is generally recommended. Around 80 percent of obese people with type 2 diabetes achieve complete remission with no need for medication if they sustain a weight loss of at least 15 kilograms (33 lb), but most patients are not able to achieve or sustain significant weight loss. Even modest weight loss can produce significant improvements in glycemic control and reduce the need for medication. Several diets may be effective such as the DASH diet, Mediterranean diet, low-fat diet, or monitored carbohydrate diets such as a low carbohydrate diet. Other recommendations include emphasizing intake of fruits, vegetables, reduced saturated fat and low-fat dairy products, and with a macronutrient intake tailored to the individual, to distribute calories and carbohydrates throughout the day. A 2021 review showed that consumption of tree nuts (walnuts, almonds, and hazelnuts) reduced fasting blood glucose in diabetic people. As of 2015, there is insufficient data to recommend nonnutritive sweeteners, which may help reduce caloric intake. An elevated intake of microbiota-accessible carbohydrates can help to reduce the effects of T2D. Viscous fiber supplements may be useful in those with diabetes. Culturally appropriate education may help people with type 2 diabetes control their blood sugar levels for up to 24 months. There is not enough evidence to determine if lifestyle interventions affect mortality in those who already have type 2 diabetes.
== Season 11 (2025) == Season 11 is themed around a haunted mansion, with returning host John Henson and judges Carla Hall, Stephanie Boswell, and Zac Young. In a change of format this season, some episodes start with all contestants in a "Haunted Heat" with the winner receiving $1000. Then, the bottom three from the first heat must compete in a "Bake for Your Life" elimination challenge.
=== 2010 census === As of the census of 2010, there were 4,025 people, 1,549 households, and 1,049 families living in the city. The population density was 1,507.5 inhabitants per square mile (582.0/km2). There were 1,641 housing units at an average density of 614.6 units per square mile (237.3 units/km2). The racial makeup of the city was 94.2% White, 0.2% African American, 0.2% Native American, 0.2% Asian, 0.1% Pacific Islander, 3.9% from other races, and 1.0% from two or more races. Hispanic or Latino of any race were 7.1% of the population. There were 1,549 households, of which 36.6% had children under the age of 18 living with them, 53.6% were married couples living together, 10.1% had a female householder with no husband present, 4.0% had a male householder with no wife present, and 32.3% were non-families. 27.8% of all households were made up of individuals, and 16.4% had someone living alone who was 65 years of age or older. The average household size was 2.54 and the average family size was 3.11. The median age in the city was 36.7 years. 27.7% of residents were under the age of 18; 6.5% were between the ages of 18 and 24; 26.4% were from 25 to 44; 20.4% were from 45 to 64; and 19% were 65 years of age or older. The gender makeup of the city was 48.3% male and 51.7% female. Ancestry breakdown of residents is German (67.6%), American (5.9%), Swedish (4.0%), Irish (2.4%), Norwegian (1.7%), English (1.2%).
== Genes == In humans, the gene for the alpha subunit is located at cytogenetic location 6q14.3. It is expressed in two cell types, most notably the basophils of the anterior pituitary. The gene for the FSH beta subunit is located on chromosome 11p13, and is expressed in gonadotropes of the pituitary cells, controlled by GnRH, inhibited by inhibin, and enhanced by activin.
Sources: en.wikipedia.org
Mass spectrometry provides the identity check, because the observed mass is compared with the theoretical mass of the AEDG sequence. Chromatography separates and quantifies impurities but does not by itself prove which peptide is present. The two techniques are normally used together.
Yes. Trifluoroacetate and acetate ions remain associated with the peptide after purification, so a weighed quantity of powder contains less peptide than the nominal mass suggests. Certificates that report net peptide content rather than raw weight are more directly comparable between suppliers.
Dilute aqueous solutions are less stable than the dry powder and are usually aliquoted and frozen to avoid repeated freeze–thaw cycles. Lyophilised material is best stored desiccated at −20 °C, protected from light. Working solutions are typically prepared fresh from a frozen aliquot.
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.