synthetic heptapeptide raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2026-03-16. Anything still debated is marked as such rather than presented as settled.
Semax is a synthetic heptapeptide whose sequence is Met-Glu-His-Phe-Pro-Gly-Pro. The first four residues correspond to the ACTH(4-10) fragment, while the terminal Pro-Gly-Pro extension was added to improve metabolic stability. Its molecular formula is C37H51N9O10S and its monoisotopic mass is approximately 813.9 Da. The compound is classified as a peptide research chemical and as a registered pharmaceutical product in Russia, but it does not hold marketing approval in the European Union or the United States. Naming conventions vary across supplier catalogs.
Development of the compound took place in the Soviet Union during the 1980s, largely through peptide research groups affiliated with the Shemyakin-Ovchinnikov Institute and Moscow State University. Investigators screened fragments of adrenocorticotropic hormone for activity on the central nervous system while attempting to separate cognitive effects from hormonal ones. The shortened sequence was selected because it retained behavioral activity in animal models without stimulating corticosteroid release. Early publications described the molecule as an ACTH(4-10) analog.
稳定性主要由水解与氧化两条路径支配。肽键在中性或弱酸性条件下相对稳定，遇到强碱或长时间高温则明显断裂；甲硫氨酸侧链容易被氧化成亚砜，使主峰前移并拉低实际含量。金属离子、光照和反复冻融会进一步促进降解或聚集。冻干粉在低温避光条件下可存放较长时间，配制后的水溶液通常需要冷藏并尽快用完。
纯度评估以反相高效液相色谱为主，通过主峰面积百分比给出粗略结果，再配合电喷雾质谱核对分子量。氨基酸分析可验证组成比例，手性色谱或毛细管电泳用于检查残基构型。常见杂质包括缺失序列的短肽、氧化产物与二聚体。由于多数市售品不附带完整检验报告，独立第三方检测常被用来核实标称值。
从分子层面看，Semax 是线性七肽，没有二硫键、糖基或脂链修饰，N 端为游离氨基，C 端为游离羧基。分子含组氨酸与谷氨酸侧链，因此在水和甲醇等极性溶剂中溶解良好，在非极性溶剂中溶解有限。计算分子量约为 814 Da，与其质子化离子的质荷比吻合，可用于质谱确认。
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Seven-residue peptide |
| Molecular mass | 813.9 Da | Monoisotopic value |
| Appearance | White to off-white powder | Lyophilized form |
| Solubility | Freely soluble in water | Also soluble in saline and polar solvents |
| Storage (dry) | -20 °C or lower | Desiccated, protected from light |
The compound is registered in Russia as a pharmaceutical product, most commonly formulated as a nasal solution, and has been used in that setting since the 1990s. Outside that jurisdiction it is generally handled as a research chemical rather than an approved medicine. Regulatory status therefore differs sharply between countries, and material sold internationally may not correspond to the Russian pharmaceutical formulation. Documentation with commercial samples is typically limited to a certificate of analysis covering purity and identity, not clinical status or local legal classification.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It corresponds to the ACTH(4-7) fragment extended at the C-terminus by a Pro-Gly-Pro tripeptide, an addition intended to slow enzymatic breakdown. The molecular formula is C37H51N9O10S and the molecular mass is approximately 814 daltons. In the literature it is often described as an ACTH(4-10) analog, although that label reflects a naming convention as much as a precise structural relationship. The compound was developed in Russia and remains most closely associated with that research tradition.
Laboratory descriptions of the material are consistent across suppliers. It appears as a white to off-white lyophilized powder that dissolves readily in water and in polar organic solvents such as dimethyl sulfoxide. Aqueous solutions are clear and colorless at low concentrations. Because the peptide contains methionine, oxidation at the sulfur atom is a recognized degradation pathway, and handling notes usually call for protected, desiccated storage. Reported purity for research-grade lots is generally above 95 percent as measured by reversed-phase high-performance liquid chromatography.
溶液状态的稳定性明显低于冻干粉。肽类在水溶液中可能经历水解、氧化与聚集，其中甲硫氨酸和天冬酰胺等残基常是敏感位点。Semax 含有甲硫氨酸，因此氧化风险相对突出。工作液一般主张现配现用，或冷藏并在数日内用尽。缓冲液种类、pH 和离子强度都会影响降解速率，而关于最佳条件的公开数据并不统一。
常规纯度与身份确认依赖反相高效液相色谱，并辅以质谱测定分子量。氨基酸组成分析可用于验证序列构成，肽图分析则能进一步定位修饰或降解产物。杂质谱通常关注缺失序列肽、截短片段和氧化产物。不同方法的检出限并不相同，因此各实验室报告的纯度数值不宜直接横向比较。
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.
Dissolution is normally performed in water, phosphate-buffered saline, or normal saline, since the peptide is freely soluble in aqueous media and is rarely handled with strong organic solvents. Solution pH should be kept near neutral, because extreme acidity or alkalinity accelerates backbone hydrolysis and encourages oxidation of the methionine side chain. Once dissolved, the material is less stable than the dry powder and is commonly divided into single-use portions and frozen. Buffers containing primary amines, such as Tris, are often avoided because of possible side reactions.
Purity assessment relies mainly on reversed-phase high-performance liquid chromatography, which separates the target heptapeptide from truncated sequences, deletion analogues, and oxidised forms. Mass spectrometry, usually coupled to liquid chromatography, confirms identity through the expected molecular ion and reveals modifications such as methionine sulfoxide formation. Amino acid analysis can verify composition, and tandem mass spectrometry supports sequence confirmation. Ultraviolet detection near 254 to 280 nanometres is convenient because the phenylalanine and histidine residues absorb in that region. Nuclear magnetic resonance is rarely used for routine release testing.
Common degradation pathways include oxidation of the methionine side chain, hydrolysis of the peptide backbone, and aggregation under unfavourable pH or concentration. Stability studies typically monitor the main peak by chromatography and report total related substances as a percentage. Because no official monograph exists, acceptance criteria vary between laboratories, and reported purity values are not directly comparable across suppliers. Analysts therefore document the method, column, and detection wavelength alongside each result, and open questions remain about how much biological activity the oxidised forms retain.
== Chemical properties == Alkanes are only weakly reactive with most chemical compounds. They only react with the strongest of electrophilic reagents by virtue of their strong C–H bonds (~100 kcal/mol) and C–C bonds (~90 kcal/mol). They are also relatively unreactive toward free radicals. This inertness is the source of the term paraffins (with the meaning here of "lacking affinity"). In crude oil the alkane molecules have remained chemically unchanged for millions of years.
== Judiciary == Hima Kohli (born 1959), Judge of the Supreme Court of India and former Chief Justice of the Telangana High Court Nalin Kohli, Indian advocate and politician Permod Kohli (born 1951), Indian Judge and former Chief Justice of Sikkim High Court Pushpa Kumari Kohli (born 1990), first female Hindu police officer in Pakistan
=== Haddie Braverman === Haddie Braverman (Sarah Ramos) is Adam and Kristina's oldest child. She is 15 in the beginning of the series. She is a straight-A student who plays soccer and has several friends; she aspires to be the quintessential "good girl" to compensate for her brother's behavioral problems. As the show progresses, however, she begins to assert her independence and experiment with boys and drugs. In Season 2, she volunteers in a soup kitchen where she meets Alex. They become romantically involved, but her parents object to their relationship because they feel Alex is too mature for her, with too many "grown-up" problems (he is a recovering alcoholic who left an abusive home and lives alone). Her parents' opposition to their relationship, as well as removing her right to privacy, causes Haddie to move out to live with her grandparents. The conflict is eventually resolved when Haddie returns home, and Adam and Kristina grant her permission to continue seeing her boyfriend. She loses her virginity to Alex the night of her junior prom. On another occasion, her parents find out she is having sex when she misdials them during sex. During the beginning of the third season, Alex gets arrested and charged with assault after punching another man at a party. Haddie feels personally responsible since he was only there to pick her up. Alex soon ends the relationship with her even after the charges are dropped because he feels that they are too different. She dedicates the rest of her senior year to school, and gets accepted into Cornell.
"The fibrous variant of Hashimoto's thyroiditis" (1974, with Austin L. Vickery Jr.) "Thymoma in a 12-year-old boy" (1976, with Jane Chatten) "Urinary Ultrastructural Findings in Fabry Disease" (1977, with Patricia J. Lyons) "Examination of Sputum in Legionnaire's Disease" (1978) "Legionnaires' disease: structural characteristics of the organism" (1978, with Philip Nash) "Leydig cell tumors of the testis" (1979, with I. Damjanov and M. A. Jewett) "Ultrastructural Features of Respiratory Cilia in Cystic Fibrosis" (1980, with Douglas S. Holsclaw Jr.) "Postinflammatory pseudotumors of the lung: fibrous histiocytoma and related lesions" (1980, with E. E. Schwartz and G. A. Mandell) "Tolmetin: Association With Reversible Renal Failure and Acute Interstitial Nephritis" (1981, with Ralph Capaldo, Erich A. Everts, and John G. DiGregorio) "Pleomorphism of Legionella pneumophila" (1984, with Shahab Hashemi, Kristy R. Brown, William A. Habib, and Jay M. Hammel) "Cilia in the Human Kidney" (1984, with Joseph J. Morgan) Legionellosis (1985) "Microscopic Nephrocalcinosis in Cystic Fibrosis" (1988, with Leslie J. Krueger and Bonita L. Falkner) "A Self-Limited Febrile Illness Produced in Guinea Pigs Associated With Oral Administration of Legionella pneumophila" (1988, with Jay M. Hammel, Joseph P. Matus, Ronald Poropatich, and Julian Katz) "Diagnostic value of electron microscopy on paraffin-embedded cytologic material" (1993, with Nancy A. Young and Sonya Naryshkin)
Sources: en.wikipedia.org
=== Controversy and conservation issues === The use and trade of elephant ivory have become controversial because they have contributed to seriously declining elephant populations in many countries. It is estimated that consumption in Great Britain alone in 1831 amounted to the deaths of nearly 4,000 elephants. In 1975, the Asian elephant was placed on Appendix I of the Convention on International Trade in Endangered Species (CITES), which prevents international trade between member states of species that are threatened by trade. The African elephant was placed on Appendix I in January 1990. Since then, some southern African countries have had their populations of elephants "downlisted" to Appendix II, allowing the domestic trade of non-ivory items; there have also been two "one off" sales of ivory stockpiles. In June 2015, more than a ton of confiscated ivory was crushed in New York City's Times Square by the Wildlife Conservation Society to send a message that the illegal trade will not be tolerated. The ivory, confiscated in New York and Philadelphia, was sent up a conveyor belt into a rock crusher. The Wildlife Conservation Society has pointed out that the global ivory trade leads to the slaughter of up to 35,000 elephants a year in Africa. In June 2018, Conservative MEPs' Deputy Leader Jacqueline Foster MEP urged the EU to follow the UK's lead and introduce a tougher ivory ban across Europe. China was the biggest market for poached ivory but announced they would phase out the legal domestic manufacture and sale of ivory products in May 2015.
=== Pharmacokinetics === Penicillin has low protein binding in plasma. The bioavailability of penicillin depends on the type: penicillin G has low bioavailability, below 30%, whereas penicillin V has higher bioavailability, between 60 and 70%. Penicillin has a short half-life and is excreted via the kidneys. This means it must be dosed at least four times a day to maintain adequate levels of penicillin in the blood. Early manuals on the use of penicillin, therefore, recommended injections of penicillin as frequently as every three hours, and dosing penicillin has been described as being similar to trying to fill a bath with the plug out. This is no longer required since much larger doses of penicillin are cheaply and easily available; however, some authorities recommend the use of continuous penicillin infusions for this reason.
Pat Striker (パトストライカー, Pato Sutoraikā): Deka Red's personal six-wheeled, police car-themed Deka Machine that forms the head and torso of Dekaranger Robo. It is also equipped with a pair of Striker Arms (ストライカーアーム, Sutoraikā Āmu), which allows it to wield the Judgement Sword (ジャッジメントソード, Jajjimento Sōdo) in its Driving Sword (ドライビングソード, Doraibingu Sōdo) formation. Pat Gyrer (パトジャイラー, Pato Jairā): Deka Blue's personal autogyro-themed Deka Machine that forms the left leg of Dekaranger Robo. It is also equipped with the Gyro Vulcan (ジャイロバルカン, Jairo Barukan) Gatling guns, the Gyro Wapper (ジャイロワッパー, Jairo Wappā) handcuffs, and the Magnet Wire (マグネワイヤー, Magune Waiyā). PaTrailer (パトレーラー, Patorērā): Deka Green's personal armored semi-trailer truck-themed Deka Machine that forms the right leg of Dekaranger Robo. It also carries the Judgement Sword and the Signal Cannon (シグナルキャノン, Shigunaru Kyanon) into battle. Pat Armor (パトアーマー, Pato Āmā): Deka Yellow's personal armored car-themed Deka Machine that forms the right arm of Dekaranger Robo. It is also equipped with floodlights, which allow it to perform the Armor Attack (アーマーアタック, Āmā Atakku) and Light Flash (ライトフラッシュ, Raito Furasshu) attacks. Pat Signer (パトシグナー, Pato Shigunā): Deka Pink's personal buggy-themed Deka Machine that forms the left arm of Dekaranger Robo. It is also equipped with a large retractable signboard.
According to data from app analytics group Sensor Tower, advertising on TikTok in the US grew by 11% in March 2023, with companies including Pepsi, DoorDash, Amazon, and Apple among the top spenders. According to estimates from research group Insider Intelligence, TikTok is projected to generate $14.15 billion in revenue in 2023, up from $9.89 billion in 2022. In March 2024, The Wall Street Journal reported that TikTok's growth in the US had stagnated.
=== Category:EC 2.1 (transfer one-carbon groups, Methylase) === Category:EC 2.1.1 Catechol-O-methyl transferase EC 2.1.1.6 DNA methyltransferase EC 2.1.1.72, EC 2.1.1.113, EC 2.1.1.37 Histone methyltransferase EC 2.1.1.43, EC 2.1.1.125 Category:EC 2.1.3 Aspartate transcarbamoylase EC 2.1.3.2 Ornithine transcarbamoylase EC 2.1.3.3
Sources: en.wikipedia.org
==== Speech by Pedro Castillo ==== Against the backdrop of the ongoing political crisis, with parliamentary groups refusing to grant confidence to the government and even loyal ministers Roberto Sánchez and Hernando Cevallos expressing dissatisfaction, President Pedro Castillo gave a speech at 6:00 p.m. on 4 February 2022. In it, he announced a cabinet reshuffle and reorganization, without specifying whether he intends to replace the president of the council. At the time of the speech, a demonstration was taking place in front of the Government Palace demanding the resignation of Héctor Valer and against the appointment of the Minister of Women Katy Ugarte, who had spoken out against education in gender history and LGBT, in April 2021.
For example, genetic mutations in pseudouridine synthases cause mitochondrial myopathy, sideroblastic anemia (MLASA) and dyskeratosis congenital. Compared to the modifications identified from other RNA species like tRNA and rRNA, the amount of identified modifications on mRNA is very small. One of the biggest reasons why mRNA modifications are not so well known is missing research techniques. In addition to the lack of identified modifications, the knowledge of associated proteins is also behind other RNA species. Modifications are results of specific enzyme interactions with the RNA molecule. Considering mRNA modifications most of the known related enzymes are the writer enzymes that add the modification on the mRNA. The additional groups of enzymes readers and erasers are for most of the modifications either poorly known of not known at all. For these reasons there has been during the past decade huge interest in studying these modifications and their function.
Alice in Chains has sold over 30 million certified records in the United States, released two number-one albums, had 23 top 40 singles, and has received eleven Grammy Award nominations. The band was ranked number 34 on VH1's 100 Greatest Artists of Hard Rock. Alice in Chains was named 15th greatest live band by Hit Parader, with Staley placing as 27th-greatest heavy metal vocalist of all time. The band's second album, Dirt, was named 5th-best album in the last two decades by Close-Up magazine in 2008. In October 2008, Guitar World ranked Cantrell's solo in "Man in the Box" at No. 77 on their list of "100 Greatest Guitar Solos". In August 2009, Alice in Chains won the Kerrang! Icon Award. In November 2011, Jar of Flies was ranked number four on Guitar World magazine's top ten list of guitar albums of 1994. It was also featured in Guitar World magazine's "Superunknown: 50 Iconic Albums That Defined 1994" list, and in May 2014, the EP was placed at number five on Loudwire's "10 Best Hard Rock Albums of 1994" list. In June 2017, Metal Injection ranked Alice in Chains at number 1 on their list of "10 Heaviest Grunge Bands". Ozzy Osbourne ranked Facelift among his list of "10 Favorite Metal Albums".
=== In the United Kingdom === Based on Appert's methods of food preservation, the tin can process was allegedly developed by Frenchman Philippe de Girard, who came to London and used British merchant Peter Durand as an agent to patent his own idea in 1810. Durand did not pursue food canning himself, selling his patent in 1811 to Bryan Donkin and John Hall, who were in business as Donkin Hall and Gamble, of Bermondsey. Bryan Donkin developed the process of packaging food in sealed airtight cans, made of tinned wrought iron. Initially, the canning process was slow and labour-intensive, as each large can had to be hand-made, and took up to six hours to cook, making canned food too expensive for ordinary people. The main market for the food at this stage was the British Army and Royal Navy. By 1817, Donkin recorded that he had sold £3000 (equal to £222,201 today) worth of canned meat in six months. In 1824, Sir William Edward Parry took canned beef and pea soup with him on his voyage to the Arctic in HMS Fury, during his search for a northwestern passage to India. In 1829, Admiral Sir James Ross also took canned food to the Arctic, as did Sir John Franklin in 1845. Some of his stores were found by the search expedition led by Captain (later Admiral Sir) Leopold McClintock in 1857.
Sources: en.wikipedia.org
It is a synthetic peptide of seven amino acids. Its backbone corresponds to a fragment of adrenocorticotropic hormone extended at the carboxyl end. The material is distributed as a lyophilized solid for laboratory use.
The extension was introduced to slow enzymatic breakdown of the peptide in biological systems. Natural ACTH fragments are degraded rapidly by peptidases. Adding the tripeptide was intended to extend the window during which the molecule remains intact.
Most published work consists of animal experiments conducted in a small number of laboratories. Human data are limited in number and size. Whether the observed effects translate into reliable clinical benefit is still unresolved.
电喷雾或基质辅助激光解吸电离质谱是常用手段，测得的质子化离子质荷比可换算为分子量。结果与理论值落在合理误差内，才支持结构一致的判断。