If you have been reading about incretin mimetic and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Updated 2026-08-01. Numbers and descriptions here follow the published literature rather than marketing material.
皮下注射后吸收相对缓慢，绝对生物利用度约为百分之八十九，血药浓度峰值通常出现在给药后一到三天。与白蛋白结合使清除减慢，终末半衰期约为一百六十五小时，接近一周。连续给药约四到五周后达到稳态暴露水平。表观分布容积约为每千克零点二五升，血浆蛋白结合率超过百分之九十九。代谢以蛋白水解切割和脂肪二酸侧链的 β-氧化为主，相关产物主要经尿液与粪便排出。
序列层面的改动同时解决了两个问题，即酶解稳定性与肾脏清除速度。天然 GLP-1 在循环中的半衰期仅约两分钟，主要被二肽基肽酶-4 迅速灭活。酰化侧链与白蛋白的可逆结合形成循环储库，使分子缓慢释放并持续激活受体。这种设计思路后来被广泛用于同类长效肽的开发，属于该类药物化学改造的典型范式。
Semaglutide 是一种经结构修饰的胰高血糖素样肽-1 类似物，其主链与内源性 GLP-1(7-36) 约有百分之九十四的序列一致性。第 8 位丙氨酸被 α-氨基异丁酸取代，使二肽基肽酶-4 无法识别原有切割位点。第 34 位赖氨酸换为精氨酸，进一步降低酶解速率。第 26 位赖氨酸经间隔基连接一条含十八个碳的二酸脂肪链，该侧链赋予分子与血浆白蛋白结合的能力。
Semaglutide is a synthetic peptide analogue of glucagon-like peptide-1, a gut hormone released after nutrient intake. The molecule contains 31 amino acid residues and differs from the native sequence at several positions. A non-natural residue at position eight resists the enzyme that normally truncates the hormone, while a lysine-linked fatty diacid side chain promotes binding to serum albumin. These two modifications extend the circulating half-life from minutes to roughly one week. The peptide is produced by solid-phase synthesis followed by selective acylation, and its identity and purity are confirmed by spectrometric and chromatographic techniques.
The primary target is the GLP-1 receptor, a class B G protein-coupled receptor expressed on pancreatic beta cells, in the gut, and in several brain regions. Receptor activation raises intracellular cyclic AMP, which potentiates glucose-dependent insulin secretion and lowers glucagon release when blood glucose is elevated. Signalling in the hypothalamus and brainstem is associated with reduced appetite and slower gastric emptying. Because the insulinotropic effect depends on prevailing glucose levels, the hypoglycaemic risk of the peptide alone is described as low in most study settings. The relative contribution of peripheral and central actions remains an active research question.
| Property | Value | Notes |
|---|---|---|
| 分子式 | C187H291N45O59 | 按主链与 C18 二酸侧链计算 |
| 分子量 | 约 4113.6 道尔顿 | 游离碱形式，随反离子略有差异 |
| 外观 | 白色至类白色冻干粉末 | 具吸湿性，需干燥保存 |
| 溶解性 | 微溶于水，易溶于碱性缓冲液 | 溶解性随 pH 升高而改善 |
| 等电点 | 约 5.4 | 影响缓冲液选择与聚集倾向 |
Activation of the GLP-1 receptor couples to Gs signalling and raises intracellular cyclic AMP in pancreatic beta cells. The resulting insulin release depends on prevailing glucose concentrations, so the effect is greater when glucose is elevated. Receptor engagement also suppresses glucagon secretion and slows gastric emptying, which flattens post-meal glucose excursions. In the central nervous system, signalling in hypothalamic and brainstem regions is associated with reduced appetite and lower energy intake. Studies continue to examine effects on cardiac, renal and hepatic endpoints; whether those benefits are independent of weight change remains an open question.
Clinical development of this compound followed earlier short-acting GLP-1 analogues that required frequent injection. Once-weekly subcutaneous formulations entered use after 2017, and an oral formulation using a permeation enhancer later became available. The oral version pairs the peptide with sodium N-(8-[2-hydroxybenzoyl] amino) caprylate, a carrier that improves uptake across the gastric epithelium. Interest has expanded from glycaemic control into weight management and metabolic liver disease. Regulatory status and approved indications differ between countries, and the product remains subject to ongoing safety monitoring.
Semaglutide is a synthetic peptide analog of glucagon-like peptide-1, a hormone released from intestinal L cells after food intake. The molecule is a 31-amino-acid backbone modified at three positions to resist cleavage by dipeptidyl peptidase-4, the enzyme that degrades native GLP-1 within minutes. A lysine residue at position 26 carries a linker and a C18 fatty diacid, which promotes binding to serum albumin and slows renal clearance. These changes extend the circulating half-life from roughly two minutes to about one week in humans.
The sequence incorporates alpha-aminoisobutyric acid at position 8, replacing the alanine found in the natural hormone. This substitution blocks the primary DPP-4 recognition site and contributes most of the enzymatic stability. Albumin binding further protects the peptide and reduces the frequency of administration required to maintain active plasma levels. Because the fatty acid chain increases lipophilicity, the compound is formulated as a solution rather than a simple aqueous buffer. Researchers describe the design as an incremental optimization of earlier GLP-1 analogs rather than a wholly new scaffold.
Reported molecular weight is approximately 4113.6 daltons for the free base, and the peptide is supplied as a lyophilized powder or in buffered liquid form depending on the intended use. It is freely soluble in water when formulated with appropriate excipients, though the unconjugated peptide shows limited stability at neutral pH over long periods. Analytical characterization typically relies on reversed-phase high-performance liquid chromatography and mass spectrometry. Purity specifications for research-grade material commonly exceed ninety-five percent by area. Isotopic and impurity profiles differ between suppliers.
The semaglutide sequence is a 31-residue analogue of human GLP-1, altered at three positions relative to the parent hormone. Aminoisobutyric acid replaces alanine at position 8, arginine replaces lysine at position 34, and a lipophilic diacid is attached to lysine 26 through a short linker. These features are reported consistently in the structural literature. The position 8 substitution blocks recognition by dipeptidyl peptidase-4, while the attached chain drives strong, reversible association with a carrier protein in blood.
Receptor activation raises intracellular cyclic AMP through Gs coupling, which promotes glucose-dependent insulin release and suppresses glucagon secretion when blood glucose is elevated. Effects outside the pancreas include slower gastric emptying and altered appetite signalling in the hypothalamus and hindbrain. The relative contribution of each tissue to overall metabolic outcomes remains an area of active investigation. Central mechanisms in particular are inferred mainly from animal models and indirect human measures rather than direct observation.
==== Anabolic and androgenic activity ==== Nandrolone has a very high ratio of anabolic to androgenic activity. In fact, many nandrolone-like anabolic steroids and even nandrolone itself are said to have among the highest ratio of anabolic to androgenic effects of all anabolic steroids. This is attributed to the fact that whereas testosterone is potentiated via conversion into dihydrotestosterone (DHT) in androgenic tissues, the opposite is true with nandrolone and similar anabolic steroids (i.e., other 19-nortestosterone derivatives). As such, nandrolone-like anabolic steroids, namely nandrolone esters, are the most frequently used anabolic steroids in clinical settings in which anabolic effects are desired; for instance, in the treatment of AIDS-associated cachexia, severe burns, and chronic obstructive pulmonary disease. However, anabolic steroids with a very high ratio of anabolic to androgenic action like nandrolone still have significant androgenic effects and can produce symptoms of masculinization like hirsutism and voice deepening in women and children with extended use.
=== Financing === In May 2016, Cerebras raised $27 million in a series A round led by Benchmark, Foundation Capital and Eclipse Ventures. In December 2016, the company raised a series B round led by Coatue Management. In January 2017, it raised a series C round led by VY Capital. In November 2018, Cerebras raised $88 million in a series D round, making the company a unicorn. Investors in this round included Altimeter, VY Capital, Coatue, Foundation Capital, Benchmark, and Eclipse. In November 2019, Cerebras raised $270 million in a series E round at a valuation of $2.4 billion. In November 2021, Cerebras raised $250 million in a Series F round, valuing the company at over $4 billion and bringing its total financing to $720 million. The Series F financing round was led by Alpha Wave Ventures and Abu Dhabi Growth Fund (ADG). In July, August, and September 2024, the company raised $85 million in a series F-1 round, selling shares for $14.66 each. In September 2025, the company raised $1.1 billion in a Series G round, selling shares for $36.23 each, or a valuation of $8.1 billion. In January 2026, the company raised $1.0 billion in a Series H round, selling shares for $89.01 each. In this round, Benchmark invested $225 million, while Alpha Wave and funds managed by Fidelity Investments each invested $100 million. On May 14, 2026, the company became a public company via the largest U.S. technology initial public offering since 2019, raising $5.55 billion by selling 30 million shares at $185 each and opening on Nasdaq at $350, valuing the company at $95 billion.
He told researchers that his memories are rich in detail, regardless of whether they are from years ago or yesterday. About 90% of his memories are in the first person, compared with an average of 66% in the general population. A team at Vanderbilt University conducted a series of tests including a brain scan that was compared with 30 age-matched controls. His brain was smaller than average (probably a result of his birth at 27 weeks). His right amygdala, however, was 20% larger, with enhanced functional connectivity between the right amygdala and hippocampus and in other regions. In 2016 HK's story was published, The Awakening of HK Derryberry: My Unlikely Friendship with the Boy Who Remembers Everything, written by his mentor Jim Bradford. In the same year, UK's Channel 4 screened the documentary The Boy Who Can't Forget, which examined the memory of 20-year-old Aurelien Hayman from Cardiff, a student at Durham University, who remembers practically every day of his life from the age of 10. The first British person to be identified with this ability, Hayman views it positively. When Hayman's brain was scanned by a team led by Professor Giuliana Mazzoni at the University of Hull, whilst he was prompted to remember a series of dates, a series of "visual areas" of the brain were activated, with much greater speed than would be expected in normal brain function. Potential problems with total recall were illustrated. The documentary also featured Bob Petrella, whose memory has enabled him to catalogue the events from his "favorite days" into a large scrapbook.
Sources: en.wikipedia.org
== History == In February 2003, Nabil Seidah and Jae Byun, a scientist at the Clinical Research Institute of Montreal in Canada, discovered a novel human proprotein convertase, the gene for which was located on the short arm of chromosome 1. Meanwhile, a lab led by Catherine Boileau at the Necker–Enfants Malades Hospital in Paris had been following families with familial hypercholesterolaemia, a genetic condition that, in 90% of cases causes coronary artery disease (FRAMINGHAM study) and in 60% of cases may lead to an early death; they had identified a mutation on chromosome 1 carried by some of these families, but had been unable to identify the relevant gene. The labs got together and by the end of the year published their work, linking mutations in the gene, now identified as PCSK9, to the condition. In their paper, they speculated that the mutations might make the gene overactive. In that same year, investigators at Rockefeller University and University of Texas Southwestern had discovered the same protein in mice, and had worked out the novel pathway that regulates LDL cholesterol in which PCSK9 is involved, and it soon became clear that the mutations identified in France led to excessive PCSK9 activity, and thus excessive removal of the LDL receptor, leaving people carrying the mutations with too much LDL cholesterol. Meanwhile, Helen H. Hobbs and Jonathan Cohen at UT-Southwestern had been studying people with very high and very low cholesterol, and had been collecting DNA samples.
First-level members are called aşıks عاشق (Albanian: ashik). They are those who, while not having taken initiation into the order, are nevertheless drawn to it. Following initiation (called nasip), one becomes a mühip محب (Albanian: muhib). After some time as a mühip, one can take further vows and become a dervish. The next level above dervish is that of baba. The baba (lit. father) (Albanian: atë) is considered to be the head of a tekke and qualified to give spiritual guidance (irshad إرشاد). Above the baba (Albanian: gjysh) is the rank of halife-baba (or dede, grandfather). The dedebaba (Albanian: kryegjysh) is traditionally considered to be the highest ranking authority in the Bektashi order. Traditionally the residence of the dedebaba was the Pir Evi (The Saint's Home) which was located in the shrine of Hajji Bektash Wali in the central Anatolian town of Hacıbektaş (aka Solucakarahüyük), known as the Hajibektash complex. Traditionally there were twelve of these hierarchical rankings, the most senior being the dedebaba (great-grandfather).
== Plot == Four years after the events of the first film, Professor Sherman Klump has created a de-aging formula. He is in a relationship with DNA researcher Denise Gaines, developer of a method to isolate genetic material. Despite his good fortune, Sherman's id alter ego, Buddy Love, has taken to sporadically controlling Sherman's body. Sherman becomes determined to permanently rid himself of Buddy when his antics ruin a dinner in honor of his father Cletus' retirement; and a marriage proposal to Denise. Despite his assistant, Jason, warning him of the harmful consequences, Sherman uses Denise's methodology to isolate and remove the DNA where Buddy has manifested. However, the Buddy genetic material grows into a sentient being when a hair from Jason's Basset Hound, Buster, accidentally lands in it. Sherman apologizes to Denise and they become engaged. Later, Dean Richmond informs them that Phleer Pharmaceuticals has offered Wellman College $150 million for the youth formula. Sherman and Denise then encounter the physically reformed Buddy at a movie theater, Buddy asks Sherman where his previous girlfriend Carla Purty is, but Sherman tells Buddy that he and Carla weren't in a romantic relationship, but rather close friends. Buddy pickpockets Sherman and learns of the $150 million offer. He subsequently visits the pharmaceutical company, making a rival bid of $149 million with Leanne Guilford, President of Acquisitions, for the youth formula. Sherman learns that the extraction has altered his body chemistry and that he is losing his intelligence.
The charged surfaces of iron (oxy)hydroxide minerals effectively adsorb elements such as phosphorus, vanadium, arsenic, and rare earth metals from seawater; therefore, although hydrothermal plumes may represent a net source of metals such as Fe and Mn to the oceans, they can also scavenge other metals and non-metalliferous nutrients such as P from seawater, representing a net sink of these elements.
Sources: en.wikipedia.org
The Reconquista was a series of military and cultural campaigns by northern Iberian Christian polities against al-Andalus. The death of the Umayyad emir Abd ar-Rahman II in 852 brought an end to Umayyad efforts to extend authority northward. The discovery in the 830s of a tomb believed to be that of James the Great gave the Christians a powerful patron, and the elevation of Alfonso III of Asturias in the 860s ended a period of uncertain leadership, thereby providing the command required to channel this energy into a wave of expansionism southward. In 868, the region between the Minho and Douro rivers was secured from the Moors by Christian forces under Vímara Peres and constituted as the County of Portugal under him. The first county of Portugal lasted until 1071. In 1096, Alfonso VI of León refounded the county and bestowed it on Henry of Burgundy, who married Alfonso's illegitimate daughter, Teresa of León.
Election forensics is the use of statistics to determine if election results are normal or abnormal. It is also used to look into and detect the cases concerning gerrymandering. Forensic accounting is the study and interpretation of accounting evidence, financial statement namely: Balance sheet, Income statement, Cash flow statement. Forensic aerial photography is the study and interpretation of aerial photographic evidence. Forensic anthropology is the application of physical anthropology in a legal setting, usually for the recovery and identification of skeletonized human remains. Forensic archaeology is the application of a combination of archaeological techniques and forensic science, typically in law enforcement. Forensic astronomy uses methods from astronomy to determine past celestial constellations for forensic purposes. Forensic botany is the study of plant life in order to gain information regarding possible crimes. Forensic chemistry is the study of detection and identification of illicit drugs, accelerants used in arson cases, explosive and gunshot residue. Forensic dactyloscopy is the study of fingerprints. Forensic document examination or questioned document examination answers questions about a disputed document using a variety of scientific processes and methods. Many examinations involve a comparison of the questioned document, or components of the document, with a set of known standards. The most common type of examination involves handwriting, whereby the examiner tries to address concerns about potential authorship.
Valve time is an industry term used jokingly with game releases from Valve, used to acknowledge the difference between the "promised" date for released content stated by Valve and to the "actual" release date; "Valve Time" includes delays but also includes some content that was released earlier than expected. Valve has acknowledged the term, including tracking known discrepancies between ideal and actual releases on its public development wiki and using it in announcements about such delays. Valve ascribes delays to its mentality of team-driven initiatives over corporate deadlines.
One such study found that administration of DSIP to humans as an adjunct to isoflurane anaesthesia actually increased the heart rate and reduced the depth of anaesthesia instead of deepening it as expected. Low plasma concentrations of DSIP have been found in patients with Cushing's syndrome. In Alzheimer's patients levels of DSIP have been found to be slightly elevated, though this is unlikely to be causal. A preparation of DSIP, Deltaran, has been used to correct central nervous system function in children after antiblastic therapy. Ten children aged 3–16 years were given a ten-day course of Deltaran and their bioelectric activity recorded. It was found that the chemotherapy-induced impairment in the bioelectrical activity of 9 out of the 10 children was reduced by administration of DSIP. DSIP can act antagonistically on opiate receptors to significantly inhibit the development of opioid and alcohol dependence and is currently being used in clinical trials to treat withdrawal syndrome. In one such trial it was reported that in 97% of opiate-dependent and 87% of alcohol-dependent patients the symptoms were alleviated by DSIP administration. In some studies administration of DSIP has alleviated narcolepsy and normalized disturbed sleeping patterns. Safety and possible side-effects of long-term DSIP use haven't been established in clinical research studies.
Taylor, Theodore (1991) [1954]. The Magnificent Mitscher. Annapolis, Maryland: Naval Institute Press. ISBN 978-1-55750-800-3. Tillman, Barrett (2006). Clash of the Carriers: The True Story of the Marianas Turkey Shoot of World War II. Penguin Group. ISBN 978-0-451-21956-5. Willmott, H. P. (1984). June 1944. New York: Blandford Press. ISBN 0-7137-1446-8. Wolborsky, Stephen L. (1994). Choke Hold: The Attack on Japanese Oil in World War II (PDF) (Thesis). Maxwell AFB, Alabama: Air University Press. Archived (PDF) from the original on 6 May 2021. Retrieved 25 November 2020. Y'Blood, William T. (1981). Red Sun Setting: The Battle of the Philippine Sea. Annapolis, Maryland: Naval Institute Press. ISBN 1-59114-994-0.
Sources: en.wikipedia.org
差别集中在三处：第 8 位残基被非天然氨基酸取代，第 34 位换成精氨酸，第 26 位增加一条脂肪酸侧链。前两处改动降低酶解速率，侧链则通过白蛋白结合延长循环时间。综合结果是半衰期从约两分钟延长到约一周。
胰岛素释放需要细胞内环腺苷酸与钙信号升高，同时依赖葡萄糖代谢产生的协同信号。血糖水平较低时协同信号不足，分泌增强有限。这一机制在降糖效果与低血糖风险之间提供了缓冲。
白蛋白结合是主要原因，它减少肾小球滤过并保护分子免受蛋白酶降解。序列修饰带来的酶解抵抗同样不可忽略，二者共同作用。脂肪链的疏水性还会影响组织分布，但其对总半衰期的贡献程度仍在研究之中。
Native GLP-1 is degraded within minutes by dipeptidyl peptidase-4 and neutral endopeptidases. Semaglutide carries a non-natural amino acid at position eight that blocks that cleavage, and a fatty diacid side chain that binds albumin. The result is a much longer duration of action than the native hormone.