The short version of lyophilisation fits in a sentence. The long version — which is the one that helps — is below.
This page was last updated on 2026-07-11 and is reviewed periodically as new material appears.
At the receptor level, the compound binds both GIP and GLP-1 receptors and triggers downstream signalling that raises cyclic AMP in target cells. GLP-1 receptor activation is associated with glucose-dependent insulin release, slower gastric emptying, and reduced appetite signalling. GIP receptor activation contributes effects that are less completely characterised, and how much each receptor adds to the overall clinical response is still an open question. The two pathways appear to interact in a complementary rather than a purely additive way.
An extended fatty diacid moiety promotes binding to serum albumin, which slows renal clearance and extends the circulating half-life to roughly five days. That property supports once-weekly administration and largely explains the dosing interval described in clinical reports. Published data come mainly from large randomised programmes that evaluated glycaemic control and body weight over periods of many months. Long-term outcomes beyond those trial windows, including what happens after treatment stops, remain an active area of investigation.
Tirzepatide is a synthetic peptide built from thirty-nine amino acids. Its sequence is derived from native glucose-dependent insulinotropic polypeptide, or GIP, with several non-natural residues and a fatty diacid side chain attached through a linker. The molecule behaves as a dual agonist at two incretin receptors, GIP and GLP-1, instead of targeting a single receptor. This dual engagement separates it from earlier single-receptor incretin compounds and underpins most of its reported pharmacological activity.
该化合物的名称与结构由国际非专利名称体系统一维持，不同文献中出现的同义写法主要在拼写顺序或盐形式描述上不同。研究者通常通过受体结合实验、细胞内环磷酸腺苷积累测定以及动物模型来确认其双激动活性。相当一部分分子层面的细节——例如两条受体通路之间的信号交叉作用——尚处于开放问题状态。
当前公开资料把 tirzepatide 归为肠促胰素类受体双重激动剂。它并非激素天然变体，而是经过序列改造的工程化肽。其分子量、等电点与疏水性等基础参数已在药典和化学数据库中收录，可作为分析检测和质量研究的参照。
Tirzepatide 是一种由 39 个氨基酸组成的合成肽，分子结构上以 GIP 序列为骨架并引入脂肪酸侧链修饰，使其能够同时与葡萄糖依赖性促胰岛素多肽（GIP）受体和胰高血糖素样肽-1（GLP-1）受体结合。这种双重激动特性使它在同类肽类药物中区别于选择性 GLP-1 受体激动剂。该分子最早由一家制药公司在 2010 年代报道，随后进入糖尿病与体重管理领域的临床研究。
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C225H348N48O68 | Free base form |
| Molecular mass | Approximately 4813 Da | Calculated from the sequence |
| Amino acid residues | 39 | GIP-derived backbone |
| Receptor targets | GIP and GLP-1 | Dual agonist |
| Circulating half-life | About 5 days | Supports weekly administration |
Development of tirzepatide took place under a research program that sought to test whether simultaneous engagement of two incretin receptors would produce greater metabolic effects than single-receptor agonism. Clinical trials were organized into the SURPASS series for type 2 diabetes and the SURMOUNT series for obesity and weight management. Regulatory clearance for type 2 diabetes came in 2022 in the United States, followed by approval for chronic weight management in 2023. The trial programs reported reductions in glycated hemoglobin and body weight relative to comparators, though long-term cardiovascular and durability data continue to accumulate.
The peptide backbone contains 39 amino acids and includes alpha-aminoisobutyric acid residues, which are not among the standard proteinogenic set. A C20 fatty diacid moiety is attached through a linker, allowing the compound to bind serum albumin and extend its circulation time. This albumin binding is the main reason the molecule supports once-weekly administration rather than more frequent dosing. The measured molecular mass is approximately 4,813 daltons, placing it firmly in the peptide rather than small-molecule class.
Solid tirzepatide is handled as a lyophilised, hygroscopic peptide powder that should be kept desiccated, protected from light, and stored frozen, typically at or below minus twenty degrees Celsius for long-term retention. Material left at ambient temperature for extended periods can take up moisture, which promotes aggregation and deamidation. Commercial liquid presentations are kept refrigerated between two and eight degrees Celsius and are not frozen. Reconstituted laboratory solutions are generally held cold and used within a short window because hydrolysis and oxidation continue slowly in solution.
Identity and purity are usually established with reversed-phase high-performance liquid chromatography for the main peak and with mass spectrometry for the observed molecular mass. Peptide mapping after enzymatic digestion confirms the primary sequence, while amino acid analysis provides a quantitative composition check. Size-exclusion chromatography and ion-exchange chromatography are used to look for aggregates and charge variants. Water content, residual solvents, and counter-ion content are measured separately, since a lyophilised powder is often reported on an as-is basis unless a correction is applied.
As a peptide, tirzepatide is handled as a lyophilised solid in research settings and as a preserved solution in finished products. Aqueous solubility is pH dependent and reaches a minimum near the isoelectric point, which lies close to pH 5.4. Stock solutions are typically prepared in neutral or slightly basic buffer to limit precipitation. The solid is hygroscopic and should be equilibrated to room temperature before opening so that condensation does not form on the powder surface.
Recommended storage for reference material is a freezer at approximately -20 degrees Celsius, protected from light and moisture. Commercial injectable presentations are stored refrigerated between 2 and 8 degrees Celsius and must not be frozen. Product labelling generally permits a limited period at controlled room temperature once dispensed, with the exact window depending on the presentation. Repeated temperature cycling is avoided because it can promote aggregation or deamidation of the peptide chain.
Identity and purity are assessed by reversed-phase high-performance liquid chromatography, with mass confirmation by electrospray ionisation mass spectrometry. Peptide mapping after enzymatic digestion verifies the primary sequence. Size-exclusion chromatography quantifies aggregates, while circular dichroism provides a secondary-structure fingerprint. Bioanalytical quantification in plasma uses immunoassay or LC-MS/MS. Reported purity for research-grade lots is commonly 95 percent or higher, and residual water content is checked by Karl Fischer titration.
Similarly, accumbal G9a hyperexpression results in markedly increased histone 3 lysine residue 9 dimethylation (H3K9me2) and blocks the induction of ΔFosB-mediated neural and behavioral plasticity by chronic drug use, which occurs via H3K9me2-mediated repression of transcription factors for ΔFosB and H3K9me2-mediated repression of various ΔFosB transcriptional targets (e.g., CDK5). ΔFosB also plays an important role in regulating behavioral responses to natural rewards, such as palatable food, sex, and exercise. Since both natural rewards and addictive drugs induce the expression of ΔFosB (i.e., they cause the brain to produce more of it), chronic acquisition of these rewards can result in a similar pathological state of addiction. Consequently, ΔFosB is the most significant factor involved in both amphetamine addiction and amphetamine-induced sexual addictions, which are compulsive sexual behaviors that result from excessive sexual activity and amphetamine use. These sexual addictions are associated with a dopamine dysregulation syndrome which occurs in some patients taking dopaminergic drugs. The effects of amphetamine on gene regulation are both dose- and route-dependent. Most of the research on gene regulation and addiction is based upon animal studies with intravenous amphetamine administration at very high doses. The few studies that have used equivalent (weight-adjusted) human therapeutic doses and oral administration show that these changes, if they occur, are relatively minor.
The great white shark (Carcharodon carcharias), also known as the white shark, white pointer, or great white, is a large shark. It is closely related to the mako sharks, the porbeagle, and the salmon shark. It is a robustly built species with a grayish upperside and a white underside. The white shark is one of the largest living shark and fish species, though it is still smaller than the whale shark and basking shark. It has about 300 triangular, serrated teeth that are continuously replaced. Its massive, fatty liver can reach over a quarter of its body weight, providing buoyancy and storing energy. The species is partially warm-blooded, an adaptation that allows it to remain active in colder waters. White sharks inhabit tropical and temperate ocean waters around the world and can be found both near coasts and in the open ocean. Populations are most concentrated at the Pacific and Atlantic of North America and in the waters of southern Africa and Oceania. They are a highly migratory species, traveling between the coast and the open ocean and even between continents. The white shark preys on marine mammals such as seals and dolphins, as well as squid and fish, including other sharks. It also scavenges whale carcasses. Though normally an apex predator, the species is sometimes preyed on by orcas. White sharks are generally solitary, but may gather in aggregations, particularly at feeding sites. They may communicate and establish dominance hierarchies with body language. The species reproduces with pups hatching from eggs inside the female before being born live.
A guide bar, typically an elongated bar with a round end of wear-resistant alloy steel typically 40 to 90 cm (15.5 to 35.5 in) in length, is used. An edge slot guides the cutting chain. Specialized, loop-style bars, called bow bars, were also used at one time for bucking logs and clearing brush, although they are now rarely encountered due to increased hazards of operation. The lower part of the chain runs in the gauge. Here, the lubrication oil is pulled by the chain to the nose. This is basically the thickness of the drive links.
In December 2024, Trump stated a further proposal for the United States to purchase Greenland from Denmark, describing "ownership" and control of the island as "an absolute necessity" for national security purposes. This builds upon a prior offer from Trump to buy Greenland during his first term, which the Danish Realm refused, causing him to cancel his August 2019 visit to Denmark. On January 7, 2025, Trump's son Donald Trump Jr. visited Greenland's capital city Nuuk alongside Charlie Kirk to hand out MAGA hats. At a press conference the following day, Trump refused to rule out military or economic force to take over Greenland or the Panama Canal. However, he did rule out military force in taking over Canada. On January 14, the Trump-affiliated Nelk Boys also visited Nuuk, handing out dollar bills to locals. On January 16, the CEOs of major Danish companies Novo Nordisk, Vestas and Carlsberg among others were assembled for a crisis meeting in the Ministry of State to discuss the situation. On the subsequent day, former chief executive Friis Arne Petersen in the Danish Ministry of Foreign Affairs described the situation as "historically unheard of", while Noa Redington, special adviser to former prime minister Helle Thorning-Schmidt, compared the international pressure on Denmark that during the 2005 Jyllands-Posten Muhammad cartoons controversy. On February 12, 2025, a bill was introduced in Congress to advance efforts to acquire Greenland and rename it Red, White, and Blueland.
== Origin and properties == The Natural History by the Roman writer Pliny the Elder includes a few sentences about a volcanic glass called obsidian (lapis obsidianus), discovered in Ethiopia by Obsidius, a Roman explorer. Obsidian is formed from quickly cooled lava. Extrusive formation of obsidian may occur when felsic lava cools rapidly at the edges of a felsic lava flow or volcanic dome, or when lava cools during sudden contact with water or air. Intrusive formation of obsidian may occur when felsic lava cools along the edges of a dike. Tektites were once thought by many to be obsidian produced by lunar volcanic eruptions, though few scientists now adhere to this hypothesis. Obsidian is mineral-like, but not a true mineral because, as a glass, it is not crystalline; in addition, its composition is too variable to be classified as a mineral. It is sometimes classified as a mineraloid. Though obsidian is usually dark in color, similar to mafic rocks such as basalt, the composition of obsidian is extremely felsic. Obsidian consists mainly of SiO2 (silicon dioxide), usually 70% by weight or more; the remainder consists of variable amounts of other oxides, mostly oxides of aluminium, iron, potassium, sodium and calcium. Crystalline rocks with a similar composition include granite and rhyolite. Because obsidian is metastable at the Earth's surface (over time the glass devitrifies, becoming fine-grained mineral crystals), obsidian older than Miocene in age is rare. Exceptionally old obsidians include a Cretaceous welded tuff and a partially devitrified Ordovician perlite.
Sources: en.wikipedia.org
The world's agrifood systems comprise a gargantuan global enterprise that each year produces approximately 11 billion tonnes of food and a multitude of non-food products, including 32 million tonnes of natural fibres and 4 billion m3 of wood. The estimated gross value of agricultural output in 2018 was US$3.5 trillion. Agrifood systems employment represented 39.1% of global employment in 2022, down from 52.2% in 2000. In 2021 primary production alone provides about one-quarter of all employment globally, more than half in sub-Saharan Africa and almost 60 percent in low-income countries. Including middle and downstream segments – from food storage and processing to transportation, retailing and consumption – agrifood systems are the backbone of many economies. Even in the European Union, the food and beverage industry employs more people than any other manufacturing sector.FAO approximates that 1.23 billion people are employed globally in agrifood systems, amounting to about one-third of the global labor force.
There are two essentially different kinds of ornithology: systematic or scientific, and popular. The former deals with the structure and classification of birds, their synonymies, and technical descriptions. The latter treats of their habits, songs, nesting, and other facts pertaining to their life histories. This early idea that the study of living birds was merely recreation held sway until ecological theories became the predominant focus of ornithological studies. The study of birds in their habitats was particularly advanced in Germany with bird ringing stations established as early as 1903. By the 1920s, the Journal für Ornithologie included many papers on the behaviour, ecology, anatomy, and physiology, many written by Erwin Stresemann. Stresemann changed the editorial policy of the journal, leading both to a unification of field and laboratory studies and a shift of research from museums to universities. Ornithology in the United States continued to be dominated by museum studies of morphological variations, species identities, and geographic distributions, until it was influenced by Stresemann's student Ernst Mayr. In Britain, some of the earliest ornithological works that used the word ecology appeared in 1915. The Ibis, however, resisted the introduction of these new methods of study, and no paper on ecology appeared until 1943. The work of David Lack on population ecology was pioneering. Newer quantitative approaches were introduced for the study of ecology and behaviour, and this was not readily accepted. For instance, Claud Ticehurst wrote:
=== Clearance in CNS === In comparison to Schwann cells, oligodendrocytes require axon signals to survive. In their developmental stages, oligodendrocytes that fail to make contact to axon and receive axon signals undergo apoptosis. Experiments in Wallerian degeneration have shown that upon injury oligodendrocytes either undergo programmed cell death or enter a state of rest. Therefore, unlike Schwann cells, oligodendrocytes fail to clean up the myelin sheaths and their debris. In experiments conducted on rats, myelin sheaths were found for up to 22 months. Therefore, CNS rates of myelin sheath clearance are very slow and could possibly be the cause for hindrance in the regeneration capabilities of the CNS axons as no growth factors are available to attract the proximal axons. Another feature that results eventually is glial scar formation. This further hinders chances for regeneration and reinnervation. Oligodendrocytes fail to recruit macrophages for debris removal. Macrophage entry in general into CNS site of injury is very slow. In contrast to PNS, microglia play a vital role in CNS Wallerian degeneration. However, their recruitment is slower in comparison to macrophage recruitment in PNS by approximately 3 days. Further, microglia might be activated but hypertrophy, and fail to transform into fully phagocytic cells. Those microglia that do transform, clear out the debris effectively. Differentiating phagocytic microglia can be accomplished by testing for expression of major histocompatibility complex (MHC) class I and II during Wallerian degeneration.
uridine (U, Urd) One of the four standard nucleosides used in RNA molecules, consisting of a uracil base with its N9 nitrogen bonded to the C1 carbon of a ribose sugar. In DNA, uridine is replaced with thymidine.
Sources: en.wikipedia.org
==== Member of the Royal Victorian Order (MVO) ==== Russell Adams, , Custodian of California Stores, Royal Collection, Royal Household. Captain Andrew Mark Aspden, Royal Navy, lately Principal Private Secretary to The Duke and Duchess of Edinburgh. Ian Charles Bartlett, Clerk of the Works, Westminster Abbey, on the occasion of the Coronation of Their Majesties The King and The Queen. Nicholas John Birch, Sergeant, Metropolitan Police Service. For services to Royalty and Specialist Protection. Ian Leslie Bullock, , Security Officer Team Leader, Palace of Holyroodhouse. Emma Jane Clarke, Secretary, Royal Farms, Windsor. Nicola Charlotte Craig, Royal Borough of Windsor and Maidenhead, on the occasion of the Coronation Concert. Andrew John Cranidge, Superintendent, Thames Valley Police, on the occasion of the Coronation Concert. Anne Maria Curran, Personal and Administration Assistant, Superintendent's Office, Windsor Castle. Sarah Louise Davis, Head of Press and Marketing, Royal Collection, Royal Household. Julie Elizabeth Denby, lately Deputy Clerk/Administrator, Greater Manchester Lieutenancy. Michael Robert Duncan, lately Special Project Advisor, Royal Household, on the occasion of the Coronation of Their Majesties The King and The Queen. Hannah Elizabeth Evans, Programme Manager, Household of The Princess Royal. David Irwin Foy, Stud Groom, Royal Paddocks, Hampton Court Palace. Christopher William Andrew Hallworth, Senior Business Applications and Infrastructure Manager, Royal Collection, Royal Household.
Few labs are subject to complaints. For 2024, CLIA budgeted for approximately 209 onsite complaint surveys, representing ~0.06% of the 320,000 CLIA labs. The low volume of lab complaints may be related to complainants' concerns about anonymity and fear of retaliation for filing a complaint. It may be easy for a lab to determine the source of a complaint filed by a lab worker. For example, in some cases, either the nature of the complaint or the piece of testing equipment in question could narrow the list of possible complainants. Because of the difficulty of protecting the anonymity of lab workers who file complaints, whistle-blower protections for such individuals are particularly important. Following congressional testimony by a Maryland hospital lab worker that she and her colleagues feared losing their jobs because of the complaints, a whistleblower protection bill, the "Clinical Laboratory Compliance Improvement Act of 2005", was introduced, but died in committee. CLIA and federal law provide no specific whistleblower protection to laboratory employees who report CLIA violations. However, CLIA complaints made under the False Claims Act (FCA) may be afforded whistleblower protections. The FCA, which prohibits fraud against government programs, including Medicare and Medicaid, may cover CLIA violations that give rise to FCA violations, such as laboratory deficiencies that render billed services medically worthless. Whether CLIA compliance is a condition of Medicare payment is a contested issue.
Hydromorphone is a semi-synthetic μ-opioid agonist. As a hydrogenated ketone of morphine, it shares the pharmacologic properties typical of opioid analgesics. Hydromorphone and related opioids produce their major effects on the central nervous system and gastrointestinal tract. These include analgesia, drowsiness, mental clouding, changes in mood, euphoria or dysphoria, respiratory depression, cough suppression, decreased gastrointestinal motility, nausea, vomiting, increased cerebrospinal fluid pressure, increased biliary pressure, and increased pinpoint constriction of the pupils.
Sources: en.wikipedia.org
It acts as a dual agonist at the GIP receptor and the GLP-1 receptor. This broader targeting profile distinguishes it from selective GLP-1 agonists, which engage only one receptor.
A fatty diacid side chain promotes binding to albumin, which delays clearance from circulation. The half-life of roughly five days makes a weekly schedule practical.
No. It is a synthetic peptide whose backbone is based on the natural incretin hormone GIP. Non-natural residues and the lipid side chain were engineered to improve stability and duration of action.
它属于合成修饰肽，同时激动 GIP 与 GLP-1 两种肠促胰素受体。这类分子通常被称为双重肠促胰素受体激动剂，与选择性 GLP-1 激动剂在靶点范围上不同。