This is a working overview of 生长激素释放激素, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2025-10-17. Anything still debated is marked as such rather than presented as settled.
Tesamorelin is a synthetic peptide that belongs to the growth hormone-releasing hormone family and contains the same forty-four amino acid sequence as endogenous GHRH, extended at the amino terminus by a trans-3-hexenoyl group. That small fatty acid modification protects the peptide from rapid cleavage by dipeptidyl peptidase-4, the enzyme that shortens the half-life of native GHRH to only a few minutes. Chemically the compound is produced by solid-phase peptide synthesis, purified by chromatography, and supplied as a sterile lyophilized powder for reconstitution.
Regulatory approval in the United States came in 2010, when the Food and Drug Administration cleared the peptide for the reduction of excess abdominal fat in adults with HIV infection and associated lipodystrophy. The decision rested mainly on two randomized phase 3 trials that enrolled roughly eight hundred patients and ran for twenty-six weeks. Participants receiving active drug showed substantially greater declines in visceral adipose tissue than those receiving placebo, while total body weight changed comparatively little. A reformulated presentation was later approved, and the product has remained a niche therapy rather than a general weight-loss agent.
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.
| Property | Value | Notes |
|---|---|---|
| Peptide class | Synthetic GHRH analogue | 44 residues; N-terminal trans-3-hexenoyl group |
| First approval year | 2010 | United States; HIV-associated abdominal fat accumulation |
| Administration route | Subcutaneous injection | Abdominal site; clinician-administered or self-injected |
| Common synonyms | TH9507; tesamorelin acetate | Development code and acetate salt form |
| Originator | Canadian biotechnology firm | Original developer and regulatory sponsor |
在临床研究之外，特沙莫瑞林常被讨论为生长激素分泌促进剂，但这一说法需要限定。它并不等同于生长激素本身，也不属于普通减重药物。部分研究关注其减少腹部脂肪和改善脂质谱的潜力，另一些研究则关注胰岛素抵抗和 IGF-1 升高等信号。这些效应的临床意义仍在评估中，尚未形成统一结论。
特沙莫瑞林是一种合成肽，其序列与人生长激素释放激素的 44 个氨基酸形式相关。它在 N 端带有反式-3-己烯酰基修饰，这一改动可减缓二肽基肽酶 IV 的降解。该化合物属于生长激素释放激素受体激动剂，可刺激垂体释放生长激素。研究文献通常将其归入合成肽类药物，而非小分子化合物。
监管记录显示，特沙莫瑞林于 2010 年在美国首次获得批准，用于人类免疫缺陷病毒感染相关的脂肪营养不良患者。批准依据来自降低内脏脂肪的临床试验，而非体重或瘦体重的普遍改善。后续出现了不同制剂版本，但其核心适应症保持一致。关于长期心血管结局和死亡率影响，现有证据仍不充分。
Binding of tesamorelin to GHRH receptors on pituitary somatotroph cells triggers cyclic AMP signaling and the release of growth hormone into circulation. Because the peptide acts upstream of the growth hormone axis, its effects are partly mediated by hepatic insulin-like growth factor 1 (IGF-1) production. The pulsatile character of endogenous growth hormone secretion is preserved rather than replaced. Whether amplified signaling produces effects beyond those of native GHRH remains an area of ongoing investigation.
A documented effect of tesamorelin is a reduction in visceral adipose tissue in some study populations. Researchers have reported decreases in trunk fat measured by computed tomography alongside changes in lipid markers. The mechanism is thought to involve growth hormone-mediated lipolysis, though the precise contribution of direct versus indirect pathways is not fully resolved. Studies have generally examined defined groups over finite periods, so long-term outcomes are less well characterized. Findings have not been uniform across all trials.
As shown in the accompanying table, the concentration of mescaline in different specimens can vary largely within a single species. Moreover, the concentration of mescaline within a single specimen varies as well. In peyote, mescaline constitutes about 30% of total alkaloid content. For comparison, the alkaloid contents of other major constituents include pellotine 17%, anhalonidine 14%, anhalamine 8%, hordenine 8%, and lophophorine 5%. It has also reported to be found in small amounts in certain members of the bean family, Fabaceae, including Senegalia berlandieri (syn. Acacia berlandieri), although these reports have been challenged and have been unsupported in any additional analyses. In plants, mescaline may be the end-product of a pathway utilizing catecholamines as a method of stress response, similar to how animals may release such compounds and others such as cortisol when stressed. The in vivo function of catecholamines in plants has not been investigated, but they may function as antioxidants, as developmental signals, and as integral cell wall components that resist degradation from pathogens. The deactivation of catecholamines via methylation produces alkaloids such as mescaline.
==== Odd atomic number ==== 53 stable nuclides have an even number of protons and an odd number of neutrons. They are a minority in comparison to the even-even isotopes, which are about 3 times as numerous. Among the 41 even-Z elements that have a stable nuclide, only two elements (argon and cerium) have no even-odd stable nuclides. One element (tin) has three. There are 24 elements that have one even-odd nuclide and 13 that have two odd-even nuclides. Of 35 primordial radionuclides there exist four even-odd nuclides (see table at right), including the fissile 23592U. Because of their odd neutron numbers, the even-odd nuclides tend to have large neutron capture cross-sections, due to the energy that results from neutron-pairing effects. These stable even-proton odd-neutron nuclides tend to be uncommon by abundance in nature, generally because, to form and enter into primordial abundance, they must have escaped capturing neutrons to form yet other stable even-even isotopes, during both the s-process and r-process of neutron capture, during nucleosynthesis in stars. For this reason, only 19578Pt and 94Be are the most naturally abundant isotopes of their element. 48 stable odd-proton-even-neutron nuclides, stabilized by their paired neutrons, form most of the stable isotopes of the odd-numbered elements; the very few odd-proton-odd-neutron nuclides comprise the others. There are 41 odd-numbered elements with Z = 1 through 81, of which 39 have stable isotopes (technetium (43Tc) and promethium (61Pm) have no stable isotopes).
== History == Nedaplatin was developed in 1983 by Shionogi Pharmaceutical Company, as an alternative to cisplatin. It was first approved for use in Japan in 1995. Cisplatin was found to cause acute renal failure in approximately one third of subjects. Nedaplatin was found to cause less nephrotoxicity and gastrointestinal toxicity when compared to cisplatin, although still moderately present, yet it was proven to have the same effectivity. As renal toxicity is a severe limiting factor in clinical use, nedaplatin is already a better alternative to Cisplatin. Despite this, Japan is the only country with full clinical legislation of nedaplatin as of 2016.
6 April U.S. Space Command, based on information collected from its planetary defense sensors, confirms the detection of the first known interstellar object. The purported interstellar meteorite, technically known as CNEOS 2014-01-08, impacted Earth in 2014, and was determined, based on its hyperbolic trajectory and estimated initial high velocity, to be from beyond the Solar System. The 2014 meteorite was detected three years earlier than the more recent and widely known interstellar objects, ʻOumuamua in 2017 and 2I/Borisov in 2019. Further related studies were reported on 1 September 2023. The first known dinosaur fossil linked to the very day of the Chicxulub impact is reported by paleontologists at the Tanis site in North Dakota. One science journalist reflects on the global management of the COVID-19 pandemic in relation to science, investigating the question "Why the WHO took two years to say COVID is airborne" – a finding hundreds of scientists reaffirmed in an open letter in July 2020 – with one indication being that this may be a major concern for many expert scientists, as evidenced by several writings published by news outlets. A study decodes electrical communication between fungi into word-like components via spiking characteristics. Researchers demonstrate semi-automated testing for reproducibility (which is lacking especially in cancer research) via extraction of statements about experimental results in, as of 2022 non-semantic, gene expression cancer research papers and subsequent testing with breast cancer cell lines via robot scientist "Eve".
Sources: en.wikipedia.org
Initially, President Eisenhower was worried that a satellite passing above a nation at over 100 kilometers (62 mi) might be seen as violating that nation's airspace. He was concerned that the Soviet Union would accuse the Americans of an illegal overflight, thereby scoring a propaganda victory at his expense. Eisenhower and his advisors were of the opinion that a nation's airspace sovereignty did not extend past the Kármán line, and they used the 1957–58 International Geophysical Year launches to establish this principle in international law. Eisenhower also feared that he might cause an international incident and be called a "warmonger" if he were to use military missiles as launchers. Therefore, he selected the untried Naval Research Laboratory's Vanguard rocket, which was a research-only rocket. This meant that von Braun's team was not allowed to put a satellite into orbit with their Jupiter-C rocket, because of its intended use as a future military vehicle. On September 20, 1956, von Braun and his team did launch a Jupiter-C that was capable of putting a satellite into orbit, but the launch was used only as a suborbital test of reentry vehicle technology.
The alkali metals are among the most electropositive elements on the periodic table and thus tend to bond ionically to the most electronegative elements on the periodic table, the halogens (fluorine, chlorine, bromine, iodine, and astatine), forming salts known as the alkali metal halides. The reaction is very vigorous and can sometimes result in explosions. All twenty stable alkali metal halides are known; the unstable ones are not known, with the exception of sodium astatide, because of the great instability and rarity of astatine and francium. The most well-known of the twenty is certainly sodium chloride, otherwise known as common salt. All of the stable alkali metal halides have the formula MX where M is an alkali metal and X is a halogen. They are all white ionic crystalline solids that have high melting points. All the alkali metal halides are soluble in water except for lithium fluoride (LiF), which is insoluble in water due to its very high lattice enthalpy. The high lattice enthalpy of lithium fluoride is due to the small sizes of the Li+ and F− ions, causing the electrostatic interactions between them to be strong: a similar effect occurs for magnesium fluoride, consistent with the diagonal relationship between lithium and magnesium. The alkali metals also react similarly with hydrogen to form ionic alkali metal hydrides, where the hydride anion acts as a pseudohalide: these are often used as reducing agents, producing hydrides, complex metal hydrides, or hydrogen gas. Other pseudohalides are also known, notably the cyanides.
=== Finland === The sale and production of alcohol was prohibited in Finland from 1919 to 1932; no current prohibition of absinthe exists. The government-owned chain of liquor stores (Alko) is the only outlet that may sell alcoholic beverages containing over 8% ABV, although national law bans the sale of alcoholic beverages containing over 80% ABV.
An antimicrobial is an agent that kills microorganisms (microbicide) or stops their growth (bacteriostatic agent). Antimicrobial medicines can be grouped according to the microorganisms they are used to treat. For example, antibiotics are used against bacteria, and antifungals are used against fungi. They can also be classified according to their function. Antimicrobial medicines to treat infection are known as antimicrobial chemotherapy, while antimicrobial drugs are used to prevent infection, which known as antimicrobial prophylaxis. The main classes of antimicrobial agents are disinfectants (non-selective agents, such as bleach), which kill a wide range of microbes on surfaces to prevent the spread of illness, antiseptics which are applied to living tissue and help reduce infection during surgery, and antibiotics which destroy microorganisms within the body. The term antibiotic originally described only those formulations derived from living microorganisms but is now also applied to synthetic agents, such as sulfonamides or fluoroquinolones. Though the term used to be restricted to antibacterials, its context has broadened to include all antimicrobials. In response, further advancements in antimicrobial technologies have resulted in solutions that can go beyond simply inhibiting microbial growth. Instead, certain types of porous media have been developed to kill microbes on contact. The misuse and overuse of antimicrobials in humans, animals and plants are the main drivers in the development of drug-resistant pathogens.
=== Biotransformation === Caffeate O-methyltransferase is an enzyme responsible for the transformation of caffeic acid into ferulic acid. Caffeic acid and related o-diphenols are rapidly oxidized by o-diphenol oxidases in tissue extracts.
Sources: en.wikipedia.org
It is a laboratory-made peptide of forty-four amino acids whose sequence matches human growth hormone-releasing hormone, with a modified amino terminus. The modification is a short unsaturated fatty acid chain attached to the first residue. This change slows enzymatic breakdown and lengthens the time the peptide stays active in circulation.
The clinical program was designed around HIV-associated lipodystrophy, a condition in which fat accumulates abnormally around the internal organs. Trials enrolled that specific population, so the evidence base covers it rather than the general population. Regulators approved the drug for the studied indication only, and promotion outside it is not permitted.
Growth hormone therapy supplies the finished hormone directly, while this peptide acts upstream and asks the pituitary to secrete its own. That difference means the response depends on a functioning pituitary and on the body's normal feedback loops. It also means the circulating hormone profile is pulsatile rather than a flat, injected level.
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.