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Last reviewed on 2026-05-15. Where a claim depends on a specific study, the study is described rather than over-claimed.
Tesamorelin is a synthetic analog of growth hormone-releasing hormone, a peptide hormone produced by the hypothalamus. The molecule retains the 44-amino-acid sequence of human GHRH and carries a trans-3-hexenoyl modification at its N-terminus. This modification increases resistance to enzymatic degradation and extends the peptide's functional stability relative to native GHRH. The compound is supplied as a lyophilized powder for reconstitution and subcutaneous administration in clinical settings. Its development code was TH9507, and it belongs to the GHRH analog class. It is not a growth hormone product; instead, it acts upstream to stimulate endogenous growth hormone release.
Clinical interest in tesamorelin arose from the need to address visceral adiposity in people living with HIV. Antiretroviral therapy improved survival but was associated in some patients with central fat accumulation, altered lipid profiles, and metabolic complications. This condition, often called HIV-associated lipodystrophy, involves excess visceral adipose tissue that is difficult to manage through diet and exercise alone. Investigators evaluated tesamorelin because GHRH analogs can stimulate growth hormone secretion and influence fat distribution without direct liposuction or invasive procedures.
A Phase 3 program led to regulatory approval in the United States in 2010 for reduction of excess visceral abdominal fat in adults with HIV and lipodystrophy. Subsequent studies examined effects on liver fat, muscle area, and metabolic markers, with mixed findings for some endpoints. Long-term cardiovascular outcomes and effects on mortality remain uncertain because most trials were relatively short and focused on imaging-based fat measurements. Use in populations without HIV has been studied experimentally but is not part of the approved indication.
特沙莫瑞林的检测通常依赖反相高效液相色谱和质谱联用。反相色谱可分离肽主峰与缺失序列、氧化产物等杂质，质谱则提供精确质量以确认身份。对于复杂基质中的定量，常采用液相色谱-串联质谱，并配合固相萃取或蛋白沉淀。生物样品中的肽易降解，因此采集和处理条件会影响结果。
稳定性研究通常考察温度、光照、湿度和 pH 对肽链的影响。冻干粉在低温避光条件下较为稳定，复溶后则需控制保存时间并避免反复冻融。肽类可能发生氧化、脱酰胺、水解和聚集，这些变化会改变色谱纯度。强制降解实验用于识别主要降解途径并验证分析方法的专属性。
质量控制项目一般包括外观、身份、纯度、含量、有关物质、水分和微生物限度。身份确认可通过肽图谱、氨基酸分析和质谱完成，纯度则用面积归一化法计算。研究级材料与药品级材料的要求不同，前者常缺少完整药典验证。不同批次间杂质谱是否影响活性，仍是一个需要具体数据回答的问题。
| Property | Value | Notes |
|---|---|---|
| Molecular weight | Approximately 5,136 Da | Based on the 44-amino-acid peptide backbone and N-terminal modification. |
| Appearance | White to off-white lyophilized powder | Usually supplied in single-use vials for reconstitution. |
| Solubility | Freely soluble in water; slightly soluble in some organic solvents | Peptide nature supports aqueous reconstitution. |
| Typical storage | 2–8 °C, protected from light | Refrigeration reduces degradation; avoid freezing unless specified. |
| Common analytical method | Reverse-phase high-performance liquid chromatography | Used for identity, purity, and quantification. |
| Synonyms | Tesamorelin, TH9507, GHRH(1-44) analog | Generic descriptors; avoid proprietary names. |
The native hormone is produced in the hypothalamus and acts on the anterior pituitary. Binding of GHRH to its receptor stimulates synthesis and release of growth hormone into circulation. Because the analogue retains the receptor-binding region of the parent sequence, it engages the same receptor and triggers the same downstream signaling. The result is increased growth hormone secretion from pituitary cells, which in turn influences hepatic production of insulin-like growth factor 1. This axis is the basis for the compound's measured biological effects.
Interest in this peptide developed because native GHRH has a short circulating lifetime. The N-terminal modification slows cleavage by dipeptidyl peptidase IV, an enzyme that removes the first two residues of many peptides and terminates their activity. Slower degradation means a longer window of receptor stimulation per administration. This design logic parallels other modified peptide hormones, where a small chemical change at a vulnerable site yields a more durable molecule without altering the core mechanism of action.
冻干粉末一般在 -20°C 或更低温度、干燥避光条件下保存，可维持较长时间的稳定。复溶后稳定性明显下降，溶液中的肽链易发生水解、氧化与聚集，通常需冷藏并在短期内用完。反复冻融会加速聚集与降解，建议分装后单次使用。缓冲体系的 pH 与离子强度同样影响聚集速率，需要按具体实验条件验证。
研究用与临床用材料的标准并不相同。质量控制通常覆盖纯度、残留溶剂、反离子含量、微生物限度与内毒素水平，各项均有对应检测方法。随货文件应包含批号、检测项目、方法与结果，使数据可以追溯。核验时应关注纯度是否按主峰面积计算、杂质是否已定性、方法是否经过验证，这些信息决定结果能否被外部重复。
== Genetics == While albinism is common, there have only been a few studies about the genetic mutations in the tyrosinase genes of animals. One of them was on Bubalus bubalis (water buffalo). The tyrosinase mRNA sequence of the wild-type B. bubalis is 1,958 base pairs (bp) with an open reading frame (ORF) of 1,593 bp long, which translates to 530 amino acids. Meanwhile, the tyrosinase gene of the albino B. bubalis (GenBank JN_887463) is truncated at position 477, caused by a point mutation in nucleotide 1431 which converts a Tryptophan (TGG) into a stop codon (TGA), resulting in a shorter and inactive tyrosinase gene. Other albinos have point mutations that appear to inactivate Tyrosinase without truncation (see table and figure for examples).
Following the Sino-Albanian split of the 1970s, a small portion of Marxist–Leninists began to downplay or repudiate the role of Mao in the Marxist–Leninist international movement in favour of the Albanian Labour Party and stricter adherence to Stalin. The Sino-Albanian split was caused by Albania's rejection of China's Realpolitik of Sino–American rapprochement, specifically the 1972 Mao–Nixon meeting which the anti-revisionist Albanian Labour Party perceived as an ideological betrayal of Mao's own Three Worlds Theory that excluded such political rapprochement with the West. To the Albanian Marxist–Leninists, the Chinese dealings with the United States indicated Mao's lessened, practical commitments to ideological orthodoxy and proletarian internationalism. In response to Mao's apparently unorthodox deviations, Enver Hoxha, head of the Albanian Labour Party, theorised anti-revisionist Marxism–Leninism, referred to as Hoxhaism, which retained orthodox Marxism–Leninism when compared to the ideology of the post-Stalin Soviet Union. In North Korea, Marxism–Leninism was superseded by Juche in the 1970s. This was made official in 1992 and 2009, when constitutional references to Marxism–Leninism were dropped and replaced with Juche. In 2009, the constitution was quietly amended so that not only did it remove all Marxist–Leninist references present in the first draft but also dropped all references to communism. Juche has been described by Michael Seth as a version of Korean ultranationalism, which eventually developed after losing its original Marxist–Leninist elements.
is the standard entropy change. Since the enthalpy should be approximately the same for the two reactions, the difference between the two stability constants is due to the effects of entropy. In equation (1) there are two particles on the left and one on the right, whereas in equation (2) there are three particles on the left and one on the right. This difference means that less entropy of disorder is lost when the chelate complex is formed with bidentate ligand than when the complex with monodentate ligands is formed. This is one of the factors contributing to the entropy difference. Other factors include solvation changes and ring formation. Some experimental data to illustrate the effect are shown in the following table.
Sources: en.wikipedia.org
Prostaglandin E1 (PGE1) is a naturally occurring prostaglandin with various medical uses. Alprostadil and misoprostol are synthetic forms of prostaglandin E1 used as medications. Lubiprostone, a derivative of prostaglandin E1, is also used as a medication. Prostaglandin E1 is a vasodilator. It has various effects in the body that include opening blood vessels, relaxing smooth muscle, inhibiting clotting, and causing uterine contractions. In infants with certain congenital heart defects, alprostadil is delivered by slow injection into a vein to maintain a patent ductus arteriosus until surgery can be carried out. By injection into the penis or placement in the urethra, alprostadil is used to treat erectile dysfunction. Common side effects when given to babies include decreased breathing, fever, and low blood pressure. When injected into the penis for erectile dysfunction; side effects may include penile pain, bleeding at the site of injection, and prolonged erection (priapism). Prostaglandin E1 was isolated in 1957 and approved for medical use in the United States in 1981. Misoprostol has various obstetric uses. It is used to induce abortion, to completely empty the uterus after a miscarriage, to induce labor, and to prevent and treat postpartum hemorrhage. The medication is available through many routes. It can be swallowed, dissolved in the mouth, placed in the vagina, or placed in the rectum. Misoprostol can also be used to manage duodenal ulcers and peptic ulcer disease when other medications are not effective.
निरन्तरान्धकारितदिगन्तरकन्दलदमन्दसुधारसबिन्दुसान्द्रतरघनाघनवृन्द-सन्देहकरस्यन्दमानमकरन्दबिन्दुबन्धुरतरमाकन्दतरुकुलतल्पकल्पमृ-दुळसिकताजालजटिलमूलतलमरुवकमिलदलघुलघुलयकलितरमणीय-पानीयशालिकाबालिकाकरारविन्दगलन्तिकागलदेलालवङ्गपाटलघनसा-रकस्तूरिकातिसौरभमेदुरलघुतरमधुरशीतलतरसलिलधारानिराकरिष्णुत-दीयविमलविलोचनमयूखरेखापसारितपिपासायासपथिकलोकान् In IAST transliteration:
=== Some documentary film awards === Grierson Awards Academy Award for Best Documentary Feature Joris Ivens Award, International Documentary Film Festival Amsterdam (IDFA), (named after Joris Ivens) Cinéma du Réel prizes, including the Grand Prix and Prix du premier film Loridan-Ivens / First Film Loridan-Ivens Award (formerly Joris Ivens Award), among others Filmmaker Award, Margaret Mead Film Festival Grand Prize, Visions du Réel
Sources: en.wikipedia.org
It is a synthetic peptide analog of human growth hormone-releasing hormone. It is used clinically to reduce excess visceral abdominal fat in adults with HIV-associated lipodystrophy. It works by stimulating pituitary growth hormone release.
Pivotal trials enrolled adults with HIV and excess visceral abdominal fat, often in the context of antiretroviral therapy. Participants were assessed mainly by computed tomography for visceral adipose tissue. The approved indication remains specific to that population.
Long-term effects on cardiovascular events, mortality, and sustained fat distribution are not well established. Most trials measured changes over months rather than years. Open questions also include whether benefits persist after treatment stops.
反相高效液相色谱用于分离和纯度评估，质谱用于分子量确认。肽图谱或串联质谱可进一步验证序列。具体方法需根据样品基质和监管要求选择。