The short version of shelf life fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-05-29. Anything still debated is marked as such rather than presented as settled.
Published research has focused mainly on neurological and cognitive endpoints in animal models, with proposed mechanisms involving brain-derived neurotrophic factor and related signalling pathways. A substantial share of the human data originates from a limited number of research groups, and independent replication in other countries remains sparse. Regulatory status reflects that distribution: the peptide is registered as a medicine in Russia and appears in some neighbouring markets, while elsewhere it is handled as a research chemical without approved therapeutic labelling. Questions about dose-response relationships, long-term effects, and comparability across studies are still open.
Lyophilised powder is normally kept at -20 °C in a desiccated container, with some suppliers recommending -80 °C for long-term archival storage. Repeated freeze-thaw cycles are the most common cause of avoidable loss, so aliquoting before freezing reduces variability between working sessions. Dissolved peptide is far less stable than the dry solid and is usually prepared fresh or held briefly at 4 °C. Aqueous solutions support both hydrolysis of the backbone and oxidation of the N-terminal methionine, and these two routes dominate degradation under ordinary laboratory conditions.
Clinical evidence consists largely of small trials with modest sample sizes, often without independent replication. Reported endpoints include cognitive scores, recovery after stroke, and visual function, but study designs vary widely and few trials meet contemporary reporting standards. Systematic reviewers have noted a high risk of bias in several of these reports. No large multicenter trial conducted outside Russia has been published. The compound is therefore best described as investigational in most jurisdictions, with its clinical role still unresolved.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Its chain combines the first seven residues of corticotropin with a C-terminal proline-glycine-proline extension, a modification intended to slow enzymatic breakdown. The free peptide has a molecular mass near 813.9 daltons. It belongs to the class of ACTH-derived fragments studied for central nervous system activity rather than for adrenal steroid stimulation. This structural relationship to a natural hormone fragment is the usual starting point for describing the compound in the literature.
Development took place during the 1980s at institutes of the Russian Academy of Sciences, where peptide fragments of ACTH were screened for cognitive and neuroprotective effects. The compound received regulatory approval in Russia as a nasal preparation, marketed for conditions such as ischemic stroke, transient ischemic attacks, and optic nerve disorders. Registration in other countries has not followed. Most published clinical reports originate from a small number of Russian research groups, and independent replication outside that setting remains limited. The regulatory status therefore differs sharply between Russia and the rest of the world.
| Property | Value | Notes |
|---|---|---|
| Purity assay | RP-HPLC, UV 214 nm | Typical research grade 95 percent or higher |
| Mass confirmation | ESI-MS or MALDI-TOF | Compared with theoretical value |
| Main degradation route | Methionine oxidation | Sulfoxide formation in solution |
| Powder storage | -20 °C, desiccated | Amber vial, minimal headspace |
| Working solution | Sterile water or saline | Prepare fresh; avoid repeated thawing |
Material sold for laboratory use varies widely in stated purity and documentation. A certificate of analysis should list the analytical method, the column and detector used, and the observed purity value. Independent verification by an outside laboratory is the practical way to confirm identity when documentation is absent or internally inconsistent. Regulatory status differs by country, and a product legal in one jurisdiction may be unapproved or controlled in another.
Identity and purity of semax are established with reversed-phase high-performance liquid chromatography coupled to ultraviolet detection, usually at 214 nanometres. Mass spectrometry, most often electrospray ionisation in positive mode, confirms the molecular mass and reveals truncated sequences. Amino acid analysis and peptide mapping after enzymatic digestion provide additional structural confirmation. Laboratories typically report purity as the percentage area of the main peak, a figure that does not capture isomeric or oxidised variants unless the method resolves them.
The peptide is prone to several degradation pathways. Oxidation of the methionine residue produces a sulfoxide that elutes close to the parent peak in many chromatographic systems. Hydrolysis of peptide bonds and deamidation of susceptible residues in related sequences also reduce purity over time. Lyophilised material kept dry at minus twenty degrees Celsius and shielded from light is the most stable form commonly described in laboratory practice.
Regulatory status differs sharply between jurisdictions. In Russia the peptide is registered as a prescription nasal preparation, while agencies such as the United States Food and Drug Administration have not approved it for any indication. Products sold elsewhere are typically labeled for laboratory research only, and such labels shift responsibility for safe handling to the purchaser. Because the same name covers pharmaceutical-grade nasal drops and bulk research powder, identity and purity documentation becomes the main practical concern when comparing sources.
Semax is a synthetic seven-amino-acid peptide whose sequence extends the ACTH(4-10) fragment with a C-terminal proline-glycine-proline tripeptide. The commonly cited sequence is Met-Glu-His-Phe-Pro-Gly-Pro, giving a molecular formula near C37H51N9O10S and a molecular weight close to 813.9 g/mol. It belongs to the broader class of synthetic ACTH fragments studied for central nervous system effects rather than for adrenal steroid stimulation. In practice the material appears as a lyophilized white powder for laboratory work or as a dilute saline solution in clinical settings.
Development is attributed to researchers at the Institute of Molecular Genetics in Moscow during the early 1980s, building on earlier Soviet work with ACTH fragments. Russian regulatory approval followed for intranasal use, and the compound has remained commercially available there for decades. Most published human data originate from Russian and, later, some Eastern European clinical reports, which are not always accessible in English translation. Outside that region the material is generally handled as a research chemical rather than a licensed medicine.
Published studies are dominated by animal models of stroke, ischemia, and cognitive impairment, with a smaller number of human trials conducted in Russia. Many of the human reports are small, single-center, and published in Russian-language journals, which limits independent scrutiny. Outcome measures vary between studies and often rely on clinician-rated scales rather than objective biomarkers. Systematic reviews have noted the methodological weaknesses and called for larger, preregistered trials before firm conclusions can be drawn.
Claims about enhanced focus, memory, or mood in healthy people rest mostly on anecdotal reports and community discussion rather than on controlled data. It remains unclear whether any cognitive benefit observed in patients recovering from brain injury would extend to uninjured users. Dose-response relationships, long-term safety, and interactions with other drugs are not well characterized in the peer-reviewed literature. Questions about optimal route of administration and treatment duration likewise remain open.
Semax binds to melanocortin receptors and is thought to influence neuronal survival and plasticity rather than to act through the adrenal axis. Laboratory work has shown increased expression of brain-derived neurotrophic factor and nerve growth factor in treated tissue. Changes in c-Fos, a marker of neuronal activation, have also been reported. Because the peptide is rapidly degraded by peptidases, its effects are generally attributed to downstream signaling cascades rather than to sustained receptor occupancy.
== Chemistry == Levobunolol is the pure L-enantiomer of bunolol and has more than 60 times the pharmacological activity of D-bunolol. It is used as the hydrochloride, which melts at 209 to 211 °C (408 to 412 °F) and is soluble in water and methanol and slightly soluble in ethanol.
== Distribution == Aristotelia chilensis is native to Chile and Argentina near the southwest coast of South America. It is found naturally in Chilean rainforests. Its native range spans the area between the Coquimbo and Aysén regions of Chile, and is 170,000 hectares (420,000 acres) in total.
== Background == He received his medical degree in 1982 from the National Autonomous University of Mexico. After postdoctoral training at University of California, San Diego (UCSD) he became a tenure-track professor at UCSD's Department of Neuroscience, with a joint appointment in Pathology. He also directed the neuropathology core of the Shirley-Marcos Alzheimer's Disease Research Center at UCSD. He was appointed head of the U.S. National Institute on Aging's Division of Neuroscience in 2016. He has a prolific body of work — over 800 research papers, much of which is now under scrutiny for containing manipulated images to support different conclusions than the real data. In September 2024, the NIH released a statement that stated he was no longer serving in the role of Director of the Division of Neuroscience.
Abdomen and obliques (belly) Crunch (i) Leg raise (c) Russian twist (c) Sit-up (c) Biceps (front of upper arms) Biceps curl (i) Pull ups with a supinated grip Calves Calf raise (i) Deltoids (shoulders) Front raise (i) Head stand into Handstand push-up (c) Lateral raise (i) Military press (c) Rear delt raise (i) Shoulder press (c) Upright row (c) Forearms Wrist curl (i) Wrist extension (i) Hamstrings (back of thighs) Deadlift (c) Frog jumping (i) Good-morning (exercise) (c) Leg curl (i) Squat (c) Lats and trapezius (back) Bent-over row (c) Chin-up (c) Pulldown (c) Pullup (c) Seated row (c) Shoulder shrug (i) Supine row (c) Lower back Deadlift (c) Good-morning (exercise) (c) Hyperextension (c) Pectorals (chest) Bench press (c) Chest fly (i) Dips (c) Machine fly (i) Push-up (c) Pelvis Vaginal weightlifting Quadriceps (front of thighs) Frog Jumping (i) Leg extension (i) Leg press (c) Lunge (c) Squat (c) Triceps (back of upper arms) Close-grip bench press (c) Dips (c) Push-down (exercise) (i) Lying triceps extensions (i)
Whites owned most of the best farmland, and had far superior education, wages and homes, but the schooling, healthcare, infrastructure and salaries available to black Rhodesians were nevertheless very good by African standards. In the wider Imperial context, Southern Rhodesia occupied a category unto itself because of the "special quasi-independent status" it held. The Dominions Office, formed in 1925 to handle British relations with the dominions of Australia, Canada, New Zealand, Newfoundland, South Africa and the Irish Free State (the Statute of Westminster 1931 delineated the rights of the dominions more clearly in that year), also dealt with Southern Rhodesia, and Imperial Conferences included the Southern Rhodesian Prime Minister alongside those of the dominions from 1932. This unique arrangement continued following the advent of Commonwealth Prime Ministers' Conferences in 1944. Southern Rhodesians of all races fought for Britain in the Second World War, and the colonial government gradually received more autonomy regarding external affairs. During the immediate post-war years, Southern Rhodesian politicians generally thought that they were as good as independent as they were, and that full autonomy in the form of dominionship would make little difference to them. Post-war immigration to Southern Rhodesia, mainly from Britain, Ireland and South Africa, caused the white community to swell from 68,954 in 1941 to 221,504 in 1961. The black population grew from 1,400,000 to 3,550,000 over the same period.
Sources: en.wikipedia.org
==== Transcutaneous lower blepharoplasty ==== In transcutaneous lower blepharoplasty, an incision is made just below the eyelashes. This approach allows for removal or repositioning of orbital fat, excision of excess skin, and modification of the orbicularis oculi muscle when necessary. It is typically used in patients with significant skin laxity.
== Presentation == Most individuals diagnosed with LECT2 amyloidosis in the United States (88%) are of Mexican descent and reside in Southwest region of the United States (New Mexico, Arizona, far Western Texas). Other groups with higher incidence rates of the disorder include First Nation Peoples in Canada, Punjabis, South Asians, Sudanese, Native Americans, and Egyptians. In Egyptians, for example, LECT2 is second most common cause of renal amyloidosis, accounting for nearly 31% of all cases. LECT2 amyloidosis (ALECT2) is generally diagnosed in individuals between the ages 40 and 90, with a mean age of 67 years old. The disorder commonly presents with renal disease that in general is advanced or at an end stage. Associated signs and symptoms of their renal disease may include fatigue, dehydration, blood in urine, and/or other evidence for the presence of the nephrotic syndrome or renal failure. Further studies may find that these individuals have histological or other evidence of LECT2 amyloid deposition in the liver, lung, spleen, kidney, and/or adrenal glands but nonetheless they rarely show any symptoms or signs attributable to dysfunction in these organs. Unlike many other forms of systemic amyloidosis, LECT2 deposition has not been reported to be deposited in the myocardium or brain of affected individuals. Thus, LECT2 amyloidosis, while classified as a form of systemic amyloidosis, almost exclusively manifests clinically as renal amyloidosis. No familial link has been found in the disorder although there have been several cases described among siblings.
== Taxonomy == At one time, all yellow or golden chanterelles in western North America had been classified as Cantharellus cibarius. Using DNA analysis, they have since been shown to be a group of related species. In 1997, the Pacific golden chanterelle (C. formosus) and C. cibarius var. roseocanus were identified, followed by C. cascadensis in 2003, C. californicus in 2008, and C. enelensis in 2017. C. cibarius var. roseocanus occurs in the Pacific Northwest in Sitka spruce forests, as well as Eastern Canada in association with Pinus banksiana.
Hydrogenases are subclassified into three different types based on the active site metal content: iron–iron hydrogenase, nickel–iron hydrogenase, and iron hydrogenase. All hydrogenases catalyze reversible H2 uptake, but while the [FeFe] and [NiFe] hydrogenases are true redox catalysts, driving H2 oxidation and H+ reduction
A Type III civilization should be detectable because of the large amount of radiation captured on a galaxy-wide scale. Calissendorff suggests using 75% of the total light emitted by a galaxy to determine that a Type III civilization uses many Dyson spheres. If only three or four of these spheres occupy the galaxy, it does not necessarily mean that the civilization has reached Type III, and it may still be in transition; however, such civilizations may remain beyond the reach of our understanding and instruments. Semay observes that "a Type III civilization should not be confused with what science fiction writers call a 'galactic empire'", knowing that it can only exist if interstellar travel is achieved. Semay argues that there is no evidence that this will ever be possible. Based on Dyson's calculations, Semay believes that such a journey would take three centuries, with an average distance between stars of about 7 light years. Overall, the speed of the colonization front, which ranges from 4×10−4 to 5×10−3 light-years/year, would result in humanity spreading throughout the galaxy in a period of 16 to 200 million. "A Type III civilization, having thus "domesticated" its galaxy by building a large number of Dyson spheres, would be detectable over intergalactic distances of several million light-years." A Type III civilization could theoretically live inside a supermassive black hole, in a stable periodic orbit, which would make it completely undetectable, according to V. I. Dokuchaev.
Sources: en.wikipedia.org
Responding to his critics on his personal website, Ayyadurai described EMAIL as "the first of its kind—a fully integrated, database-driven, electronic translation of the interoffice paper mail system derived from the ordinary office situation." He maintained that EMAIL was the first electronic mail system to integrate an easy-to-use user interface, a word processor, a relational database, and a modular inter-communications protocol "integrated together in one single and holistic platform to ensure high-reliability and user-friendliness network-wide." Ayyadurai presented a press release on his webpage asserting that his undergraduate professor Noam Chomsky, of MIT's Department of Linguistics and Philosophy, also supported his claims. According to various historians, Ayyadurai honed his claims appeal to those with particular political leanings by arguing that his achievements are overlooked due to "racism, anti-immigrant prejudice, historians in the pay of big business, and a belief that only elite and well-funded institutions can create innovations." In March 2016, Ayyadurai complained about Raytheon, where Tomlinson worked on ARPANET. After Tomlinson's death, Ayyadurai told The Hindu that he believed that news outlets retracted their stories about him because, "Raytheon advertises in publications like the Huffington Post and CNN" and that if he were "a white guy and had a copyright for email, I would have my photo on every stamp in the world." The day after Tomlinson's death, Ayyadurai tweeted: "I'm the low-caste, dark-skinned, Indian, who DID invent #email.
=== Activism === Throughout her life, Kidder was active in environmental and anti-nuclear causes. On August 23, 2011, Kidder, Tantoo Cardinal, and dozens of others were arrested while protesting in Washington, DC, against the proposed extension of the Keystone Pipeline. In 2012, she appeared in a video for Stop the Frack Attack, an environmental organization working toward regulating hydraulic fracturing ("fracking") practices. When discussing sustainable energy, Kidder said: "The first thing people have to start facing, contrary to the advertising fed to us by oil and gas companies, is that environmentalism and economic stability go hand-in-hand on any long-term basis." Kidder spent the winter of 2016–2017 residing in a tent at the Standing Rock Reservation in North Dakota, protesting the Dakota Access Pipeline. In addition to environmental causes, Kidder was a vocal supporter of LGBTQ rights, and in 2003, hosted benefits at a gay and lesbian health center in Boston, Massachusetts. Following her publicized nervous breakdown in 1996, she also spoke outwardly about her struggles with mental health and her bipolar disorder diagnosis. In 2001, she was awarded the Courage in Mental Health Award from the California Women's Mental Health Policy Council for her public dialogue on mental illness.
=== 2012—2017: ZeniMax Media subsidiaries === Antonov also worked on Dishonored's DLC. Following this, Antonov became the visual design director for American company ZeniMax Media, meaning he worked on projects developed by ZeniMax's subsidiary developers—including Bethesda Game Studios, MachineGames, id Software, and Arkane—and made sure "the level of visual design and fiction" coming out of them was "the highest possible", Robert Purchese wrote. In 2012, a ZeniMax subsidiary named BattleCry Studios was founded in Austin, Texas, by developer Rich Vogel. Antonov worked on their planned debut release, a team-based multiplayer FPS titled BattleCry. In 2015, Bethesda Softworks, the planned publisher of BattleCry, revealed their "concerns" about the viability of the game releasing, and it was cancelled in 2017. Antonov was the additional art director of MachineGames' Wolfenstein: The New Order (2014); a visual designer of Dire Wolf Digital's The Elder Scrolls: Legends (2017); and a consultant on Bethesda Game Studios' Fallout 4 (2015), id Software's Doom (2016), and Arkane's Dishonored 2 (2016) and Prey (2017).
=== Restriction enzymes then gel electrophoresis === Restriction enzymes are first used to recognize and then cut specific nucleic acid sequences. These cut pieces of DNA can be run through a gel electrophoresis to allow diagnostics of the organism by referencing back to previous gel electrophoresis results.
== History == The backdoor pathway to DHT biosynthesis was discovered in early 2000s in the marsupials and later confirmed in humans. That is why the backdoor pathway of DHT biosynthesis from 17OHP can be called a marsupial pathway. This pathway is also present in other mammals, such as rats, and are studied in the other mammals as a way to better understand these pathways in humans. Marsupials, and in particular, tammar wallabies (Notamacropus eugenii) are especially useful for studying the processes of sexual differentiation and development in the context of androgen biosynthesis, because sexual differentiation in these species occurs only after birth, with testes beginning to form two days after birth and ovaries only on the eighth day after birth. This feature of post-natal early sexual differentiation allows scholars to study the influence of hormones on the body from the very beginning of the process of sexual differentiation, as well as the pathways of biosynthesis of these hormones. Tammar wallabies are particularly interesting due to the fact that all these hormones, pathways, and the ways in which hormones affect body features and growth of different organs can be studied when the organism is already born, unlike in other mammals such as rats, where sexual differentiation in a fetus occurs inside the placenta before birth.
Sources: en.wikipedia.org
Reversed-phase HPLC gives the main purity figure, most often with UV detection near 214 nanometres. Mass spectrometry then confirms the molecular mass. Together the two methods distinguish a correct sequence from a closely related impurity.
The main chemical risks are methionine oxidation and backbone hydrolysis in solution. Moisture and repeated temperature cycling accelerate both processes. Dry powder held cold and desiccated is considerably more stable than any reconstituted preparation.
It holds a medicine registration in Russia, where it has been used clinically for decades. In most other countries it is treated as a research chemical. That split explains the uneven distribution of clinical literature.
Semax is a synthetic seven-amino-acid peptide derived from a fragment of corticotropin. It is used in Russia as a nasal preparation, while elsewhere it is studied as a research compound. It is not approved as a medicine in most countries.