Everything below concerns 双受体激动. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2025-09-05. Numbers and descriptions here follow the published literature rather than marketing material.
Structure-activity work shows that fatty acid length, linker chemistry and the position of acylation all influence albumin affinity and receptor potency. Plasma protein binding exceeds 99 percent, which restricts distribution and slows renal clearance. Degradation proceeds largely through general proteolysis and fatty acid oxidation rather than cytochrome P450 metabolism, so exposure to common oxidative drug interactions is limited. Whether these clearance routes vary meaningfully between individuals is not fully established.
The molecule is a synthetic 39-amino-acid peptide whose backbone derives from the sequence of human glucose-dependent insulinotropic polypeptide, with several substitutions that raise metabolic stability and shift receptor preference. A C20 fatty diacid is attached through a short linker to a lysine side chain, a modification that increases binding to serum albumin. The reported monoisotopic mass is approximately 4813 Da. Near neutral pH the peptide carries a net negative charge, and the lipid tail makes the molecule markedly more hydrophobic than the unmodified parent sequence.
Dual agonism at the GIP and GLP-1 receptors underlies the observed pharmacology. Activation of GLP-1 receptors raises glucose-dependent insulin release, lowers glucagon secretion, slows gastric emptying and reduces appetite. GIP receptor activation contributes additional effects on adipose tissue and on energy balance, and the combined action on appetite appears larger than either pathway alone in animal models. Signalling bias and the relative contribution of each receptor arm to weight-related effects remain areas of active investigation.
Structural work on the molecule centers on a C20 fatty diacid moiety attached through a linker to the peptide backbone. This side chain promotes reversible binding to serum albumin, which slows renal clearance and supports a prolonged action profile. The peptide backbone incorporates aminoisobutyric acid substitutions that limit recognition by digestive enzymes. Together these modifications produce a molecule that is stable enough for subcutaneous delivery but still dependent on careful manufacturing control. Analytical characterization of the active pharmaceutical ingredient typically follows the conventions used for other synthetic peptides.
Tirzepatide is a synthetic peptide composed of 39 amino acids. It acts as a dual agonist at two incretin receptors, the glucose-dependent insulinotropic polypeptide receptor and the glucagon-like peptide-1 receptor. The molecule was designed by modifying the native sequence of glucose-dependent insulinotropic polypeptide to improve metabolic stability and extend its circulation time. Its structure includes several non-natural amino acid residues and a fatty acid side chain. These features distinguish it from earlier single-receptor incretin analogs studied in the same period.
The compound first appeared in the scientific literature as an investigational agent for type 2 diabetes. Clinical development proceeded through phase 1, phase 2, and phase 3 programs that measured glycemic control as a primary endpoint while recording body weight as a secondary outcome. Regulatory approval in the United States followed in 2022 for glycemic control, and a separate indication for chronic weight management was added later. Subsequent trials have examined cardiovascular outcomes in adults with elevated cardiovascular risk. Debates continue over how much of the observed effect derives from each receptor arm.
| Property | Value | Notes |
|---|---|---|
| Molar mass | approximately 4813 Da | calculated from the 39-residue sequence |
| Appearance | white to off-white powder | typical of lyophilised peptide material |
| Solubility class | freely soluble in water | measured value depends on salt form and pH |
| Plasma protein binding | >99 percent | linked to the fatty diacid side chain |
| Class | dual GIP and GLP-1 receptor agonist | receptor activity varies with the assay used |
Cold-chain handling is standard for formulated product, with dry powder stored frozen and ready-to-use solutions refrigerated. Light exposure is minimized because photodegradation of certain amino acid side chains is possible. Shipping and temperature-excursion studies are used to establish whether short deviations affect quality attributes. Documentation supplied with research material usually includes a certificate of analysis listing purity, identity confirmation, and water or residual solvent content. Users are expected to confirm that material meets the stated specification before use.
Identity and purity of tirzepatide are assessed mainly by reversed-phase high-performance liquid chromatography with ultraviolet detection, often paired with mass spectrometry. Because the molecule carries several modifications, gradient conditions are adjusted to resolve the intact peptide from deamidation and oxidation products. Enzymatic digestion followed by peptide mapping confirms the primary sequence and locates specific modifications. Quantitation in biological matrices typically uses liquid chromatography with tandem mass spectrometry after solid-phase extraction. Immunoassays are used less often, since antibody cross-reactivity with closely related peptides can bias results.
The peptide shares degradation routes common to modified peptides: deamidation of asparagine and glutamine residues, oxidation of methionine, and backbone hydrolysis under extreme pH. Lyophilized material is generally more stable than a solution, and residual water content directly affects the rate of hydrolysis. In liquid form, aggregation and visible particles can appear after agitation or repeated freeze-thaw cycles. Stability studies therefore track monomer content, aggregate content, and potency over months under defined temperature and humidity.
纯度评估通常综合反相色谱、体积排阻色谱与质谱三方面信息：前者反映疏水性杂质，后者反映聚集体，质谱则确认分子量与主要降解产物。有关降解途径的完整图谱——例如脱酰胺、氧化与水解各占多大比例——在不同储存条件下仍有差异，属于需要逐案验证的问题。
质量控制环节关注外观、含量、纯度、有关物质、水分与微生物限度等项目。检测结果需要有对照品和系统适用性数据支持，单次测定不足以判定批次的稳定性。实验室之间方法转移时，色谱柱品牌与梯度差异常导致保留时间漂移，因此方法验证十分必要。
固体状态的 tirzepatide 通常以冻干粉形式保存，推荐在低温、避光、干燥条件下存放，常见区间为 2 至 8 摄氏度，长期保存可考虑更低温度并避免反复冻融。冻融循环会导致肽链聚集或析出，从而影响后续定量结果。容器密封性与湿度控制同样是稳定性研究中反复强调的因素。
Both receptors are class B G protein-coupled receptors that signal largely through Gs-mediated cyclic AMP production. Activation within pancreatic islets increases glucose-dependent insulin secretion and suppresses glucagon release when glucose is elevated. Outside the pancreas, signaling in the central nervous system and gut appears to influence appetite and gastric emptying. The relative contribution of each receptor to observed clinical effects remains under investigation, and the two pathways are not simply additive in practice.
Reported outcomes in large trials include dose-dependent weight reduction and improvements in glycemic markers over periods ranging from several months to more than a year. Whether the compound alters long-term cardiovascular or renal outcomes is being examined in dedicated outcome studies, so those questions remain open. Labeling describes gastrointestinal effects such as nausea and diarrhea, which tend to appear during dose escalation. Discontinuation rates and the durability of effects after treatment stops vary across study populations and are still debated.
Tirzepatide is a synthetic peptide developed as a dual agonist at the glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1 receptors. Its structure is built on a GIP-derived backbone with non-natural amino acid substitutions and a fatty diacid side chain that promotes albumin binding and slows clearance. That modification supports once-weekly subcutaneous dosing. Registrational trial programs reported reductions in body weight and glycated hemoglobin alongside the drug's glycemic effects.
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。
Vantin (by Pfizer) in suspension or tablet form. Toraxim (by Delta Pharma Ltd., Bangladesh) Trucef (by Renata Limited, Bangladesh) Tricef (by Alkaloid Skopje, North Macedonia) Orelox (by Sanofi-Aventis) MAPDOX-CV: Combination cefpodoxime–clavulanic acid MONOTAX O (cefpodoxime)/MONOTAX CV (cefpodoxime–clavulanic acid) by Zydus Healthcare Ltd. ACXIME 200/CV (by Allencia Biosciences, India) POSTPOD-50 (cefpodoxime 50mg/5ml) by Laafon Galaxy Pharmaceuticals
Further LLM developments during what has been called an "AI boom" include: local or open source versions of LLaMA which was leaked in March, news outlets report on GPT4-based Auto-GPT that given natural language commands uses the Internet and other tools in attempts to understand and achieve its tasks with unclear or so-far little practicality, a systematic evaluation of answers from four "generative search engines" suggests their outputs "appear informative, but frequently contain unsupported statements and inaccurate citations", a multi-modal open source tool for understanding and generating speech, a data scientist argues that "researchers need to collaborate to develop open-source LLMs that are transparent" and independent, Stability AI launches an open source LLM. On 12 April, researchers demonstrate an 'AI scientist' that can create of models of natural phenomena from knowledge axioms and experimental data, showing the software can rediscover physical laws using logical reasoning and few data points. Promising results of therapeutic candidates are reported: a review suggests daily vitamin D3 may reduce cancer mortality by around 12% (31 Mar), review of experimental phototherapies against dementia cognitive decline (5 Apr), mice-tested L.
=== Adoption in precolonial scholarship === The earliest attempt to associate the people of the Gold Coast with ancient Ghana had been made by Rev. J. B. Anaman around the turn of the 20th century. Anaman drew on W.D. Cooley's 19th-century interpretation of Arabic geographical sources to make an argument for a historical connection, suggesting an alternative derivation connecting the name to the Wangara people. Lady Flora Shaw later compiled both Arabic and European writings to create detailed narratives of the kingdom. She presented it as a major African power comparable to contemporary Western European states. According to Jack Goody, the theory that the Akan peoples originated from the medieval Empire of Ghana was continuously promoted through the teachings of Rev. W. T. Balmer between 1907 and 1911, who instructed students that the Akan had migrated from the ancient kingdom located near the Upper Niger. Goody states that Balmer's hypothesis lacked linguistic and historical evidence, yet it later became influential among educated elites and nationalist intellectuals. The hypothesis gained more popularity when it was introduced into educational institutions, primarily in Achimota, during the 1920s where it later spread to other schools. The theory was later publicized by J. B. Danquah's academic writings; he used Arabic and French translations to claim that the Akan migrated from the Upper Niger region. Danquah proposed that the term Ghana was a corruption of Akane or Akana and associated it with the ancient region of Akkad. Eva L. R.
== History and taxonomy == The fungus was first isolated in 1870 from a tinea cruris patient in Germany by Carl Otto Harz, who named it Acrothecium floccosum. Being unaware of Harz's work, Castellani and Sabouraud identified the species again in 1905 and 1907, respectively, and both placed the fungus into the genus Epidermophyton. Epidermophyton is one of the three dermatophyte fungal genera; it is distinct from the other two genera (Microsporum and Trichophyton) for the absence of microconidia. In 1930, based on the principle of priority, Langeron and Milochevitch renamed the fungus Epidermophyton floccosum to recognize Harz's contribution in identifying the species first, as well as his extensive morphological descriptions. Another fungus, originally named Epidermophyton stockdaleae, is a dark-brown, soil-inhabiting species that is morphologically and molecularly distinct to E. floccosum for its longer conidia and 7% NaCl tolerance. E. stockdaleae is also clinically differentiated from E. floccosum by its ability in perforating hair. Due to the presence of microconidia, E. stockdaleae is now considered a synonym of Trichophyton ajelloi, hence E. floccosum is currently the only species in the genus Epidermophyton.
=== Synthetic dipeptides === Dipeptides are produced by coupling amino acids. The amino group on one amino acid is rendered non-nucleophilic (P in eq) and the carboxylic acid group in the second amino acid is deactivated as its methyl ester. The two modified amino acids are then combined in the presence of a coupling agent, which facilitates formation of the amide bond:
Sources: en.wikipedia.org
In 2008, the Welsh Assembly government announced its intention to establish demonstration sites for take-home naloxone, and in 2010, Scotland instituted a national naloxone program. Inspired by North American and European efforts, non-governmental organizations running programs to train drug users as overdose responders and supply them with naloxone are now operational in Russia, Ukraine, Georgia, Kazakhstan, Tajikistan, Afghanistan, China, Vietnam, and Thailand. In October 2018, Emergent BioSolutions announced it would provide a free kit including two doses of the nasal spray, as well as educational materials, to each of the 16,568 public libraries and 2,700 YMCAs in the U.S. In 2025, an American start-up released a keychain case to make naloxone more immediately accessible in emergencies. In April 2025, the city of Nashville, Tennessee introduced its first naloxone vending machine at a gas station on West End Avenue. Within five weeks of installation, the machine had dispensed over 2,200 doses, significantly surpassing initial expectations. The program was funded by opioid settlement money. In November of the same year, the city introduced two more naloxone vending machines. Other efforts to support community access have included partnerships with first response agencies around the United States to work with them to send "push messages" about getting trained on overdose response and carrying naloxone to residents in their communities.
== Medical uses == Omacetaxine/homoharringtonine was indicated for use as a treatment for patients with chronic myeloid leukaemia who are resistant or intolerant of tyrosine kinase inhibitors. In June 2009, results of a long-term open label Phase II study were published, which investigated the use of omacetaxine infusions in CML patients. After twelve months of treatment, about one third of patients showed a cytogenetic response. A study in patients who had failed imatinib and who had the drug resistant T315I mutation achieved cytogenetic response in 28% of patients and hematologic response in 80% of patients, according to preliminary data. Phase I studies including a small number of patients have shown benefit in treating myelodysplastic syndrome (MDS, 25 patients) and acute myelogenous leukaemia (AML, 76 patients). Patients with solid tumors did not benefit from omacetaxine.
Subsequent experiments showed that the 19 "cold" amino acids were not necessary and that the protein product had the biochemical characteristics of polyphenylalanine, demonstrating that a chain of repeated uracil bases produced a protein chain made solely of the repeating amino acid phenylalanine. While the experiment did not determine the number of bases per codon, it was consistent with the triplet codon UUU coding for phenylalanine. In analogous experiments with other synthetic RNAs, they found that poly-C directed synthesis of polyproline. Nirenberg recounts that the labs of Severo Ochoa and James Watson had earlier done similar experiments with poly-A, but failed to detect protein synthesis because polylysine (unlike most proteins) is soluble in trichloroacetic acid. Further, using synthetic RNAs that randomly incorporated two bases at different ratios, they produced proteins containing more than one type of amino acid, from which they could deduce the triplet nature of the genetic code and narrow down the codon possibilities for other amino acids. Nirenberg's group eventually decoded all the amino acid codons by 1966, however this required additional ingenious experimental methods (see Nirenberg and Leder experiment).
She suggests that other acts of violence, including the killing of Dlamini and other black councillors, were "spontaneous and resulted from hostile interactions between crowds, police and councillors". The South African Police responded initially with tear gas and rubber bullets, and then began using live ammunition; heavily armed reinforcements were brought in and continued to battle protestors overnight. The government reported 14 fatalities, including some as a result of police "countermeasures". The following morning – as rioting continued in Sharpeville, Sebokeng, and Evaton – figures were revised upwards to 29 fatalities and an estimated 300 injuries, including at least a handful of injured policemen. It was therefore the bloodiest day of protests in South Africa since the 1976 Soweto uprising. In 1976, however, the police had unambiguously been responsible for the overwhelming majority of deaths; in Vaal, it was clear that deaths had been caused by protestors as well as by police, though it was not clear in what proportions. Rueedi calculates that protestors killed four councillors and that the rest of the victims were shot by police. The protests of 3 September turned into a popular uprising across several regions of the country, with many further deaths – 40 by the end of the first week. The unrest spread to Soweto, the country's largest township, the next week.
=== Outer membrane vesicle === Outer membrane vesicles (OMVs) are naturally immunogenic and can be manipulated to produce potent vaccines. The best known OMV vaccines are those developed for serotype B meningococcal disease.
Sources: en.wikipedia.org
== Ecology == P. lateralis has been identified in Iraq as a host for larvae of the parasitoid wasp Ampulex assimilis. An adult wasp stings the cockroach, pulls or leads it by its antenna to the wasp's nest, deposits its egg on the femur of the cockroach's midleg, then closes the nest with debris. Upon hatching, the wasp larva feeds externally, then bores into the cockroach for further food and pupation.
==== Cleaved, contracted, and expanded rings ==== Secosteroids (Latin seco, "to cut") are a subclass of steroidal compounds resulting, biosynthetically or conceptually, from scission (cleavage) of parent steroid rings (generally one of the four). Major secosteroid subclasses are defined by the steroid carbon atoms where this scission has taken place. For instance, the prototypical secosteroid cholecalciferol, vitamin D3 (shown), is in the 9,10-secosteroid subclass and derives from the cleavage of carbon atoms C-9 and C-10 of the steroid B-ring; 5,6-secosteroids and 13,14-steroids are similar. Norsteroids (nor-, L. norma; "normal" in chemistry, indicating carbon removal) and homosteroids (homo-, Greek homos; "same", indicating carbon addition) are structural subclasses of steroids formed from biosynthetic steps. The former involves enzymic ring expansion-contraction reactions, and the latter is accomplished (biomimetically) or (more frequently) through ring closures of acyclic precursors with more (or fewer) ring atoms than the parent steroid framework. Combinations of these ring alterations are known in nature. For instance, ewes who graze on corn lily ingest cyclopamine (shown) and veratramine, two of a sub-family of steroids where the C- and D-rings are contracted and expanded respectively via a biosynthetic migration of the original C-13 atom. Ingestion of these C-nor-D-homosteroids results in birth defects in lambs: cyclopia from cyclopamine and leg deformity from veratramine. A further C-nor-D-homosteroid (nakiterpiosin) is excreted by Okinawan cyanobacteriosponges.
3-phosphoglycerate dehydrogenase deficiency 3-phosphoserine phosphatase deficiency Phosphoserine aminotransferase deficiency These enzyme defects lead to severe neurological symptoms such as congenital microcephaly and severe psychomotor retardation and in addition, in patients with 3-phosphoglycerate dehydrogenase deficiency to intractable seizures. These symptoms respond to a variable degree to treatment with L-serine, sometimes combined with glycine. Response to treatment is variable and the long-term and functional outcome is unknown. To provide a basis for improving the understanding of the epidemiology, genotype/phenotype correlation and outcome of these diseases their impact on the quality of life of patients, as well as for evaluating diagnostic and therapeutic strategies a patient registry was established by the noncommercial International Working Group on Neurotransmitter Related Disorders (iNTD). Besides disruption of serine biosynthesis, its transport may also become disrupted. One example is spastic tetraplegia, thin corpus callosum, and progressive microcephaly, a disease caused by mutations that affect the function of the neutral amino acid transporter A.
Car hit and runs, burglaries, assaults, drive-by shootings and bombings such as these situations may cause glass fragments that could be used as evidence of association in glass transfer conditions. LA-ICP-MS is considered one of the best techniques for analysis of glass due to the short time for sample preparation and sample, small sample size of less than 250 nanograms. In addition there is no need for complex procedure and handling of dangerous materials that is used for digestion of the samples. This allows detecting major, minor and tracing elements with high level of precision and accuracy. There are set of properties that are used to measure glass sample such as physical and optical properties including color, thickness, density, refractive index (RI) and also, if necessary, elemental analysis can be conducted in order to enhance the value of an association.
The polymerization cofactor profilin and the ATP·actin combine to form a profilin-ATP-actin complex that then binds to the end-tracking unit The cofactor and monomer are transferred to the barbed-end of an actin already clamped filament The tracking unit and cofactor dissociate from the adjacent protofilament, in a step that can be facilitated by ATP hydrolysis energy to modulate the affinity of the cofactor and/or the tracking unit for the filament; and this mechanoenzymatic cycle is then repeated, starting this time on the other sub-filament growth site. When operating with the benefit of ATP hydrolysis, AC motors generate per-filament forces of 8–9 pN, which is far greater than the per-filament limit of 1–2 pN for motors operating without ATP hydrolysis. The term actoclampin is generic and applies to all actin filament end-tracking molecular motors, irrespective of whether they are driven actively by an ATP-activated mechanism or passively. Some actoclampins (e.g., those involving Ena/VASP proteins, WASP, and N-WASP) apparently require Arp2/3-mediated filament initiation to form the actin polymerization nucleus that is then "loaded" onto the end-tracker before processive motility can commence. To generate a new filament, Arp2/3 requires a "mother" filament, monomeric ATP-actin, and an activating domain from Listeria ActA or the VCA region of N-WASP. The Arp2/3 complex binds to the side of the mother filament, forming a Y-shaped branch having a 70-degree angle with respect to the longitudinal axis of the mother filament.
Sources: en.wikipedia.org
It is a synthetic peptide of 39 amino acids bearing a lipid side chain. Its size and architecture place it outside the small-molecule class, and laboratories generally handle it with the precautions used for biologic-like molecules.
The fatty diacid side chain promotes strong binding to serum albumin, which slows clearance and yields a half-life of roughly five days. That profile supports once-weekly administration in clinical use.
In vitro assays detect activity at both the GIP and GLP-1 receptors, but the activity ratio depends on the assay system and the signalling pathway measured. The relative contribution of each receptor to clinical effects is still being characterised.
It activates both the glucose-dependent insulinotropic polypeptide receptor and the glucagon-like peptide-1 receptor. This dual activity separates it from agents that act on only one of the two receptors. The relative contribution of each receptor to clinical effects remains an open area of study.