This is a working overview of 冻干粉, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2025-11-22. 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.
Studies of the compound rely on imaging and laboratory endpoints rather than on symptoms alone. Visceral adipose tissue is usually quantified by computed tomography or magnetic resonance imaging at the level of the abdomen, with waist circumference serving as a cheaper but less specific proxy. Blood work tracks insulin-like growth factor 1, fasting glucose, glycated hemoglobin, and lipid fractions. In the pivotal trials the imaging endpoint fell by roughly fifteen to twenty percent over six months, subcutaneous fat changed little, and the visceral fat returned toward baseline after treatment stopped, a pattern that shapes how clinicians discuss durability.
Whether the drug improves hard clinical outcomes is not settled. No completed trial has shown a reduction in heart attacks or strokes among treated patients, although a dedicated cardiovascular outcomes study has been discussed in the literature. Investigators have also examined hepatic fat in people with HIV and fatty liver disease, cognitive measures in small cohorts, and changes in bone density. Regulatory labeling emphasizes monitoring of insulin-like growth factor 1 because supraphysiologic levels raise questions about tissue growth, and the clinical significance of that signal remains an open question rather than a demonstrated harm.
Binding of tesamorelin to the growth hormone-releasing hormone receptor on anterior pituitary somatotrophs activates a Gs protein pathway, raises cyclic AMP, and triggers release of stored growth hormone into the bloodstream. Because the analogue resists dipeptidyl peptidase-4, its plasma residence time exceeds that of native GHRH, producing a larger and more sustained secretory signal. The released growth hormone then acts on the liver and peripheral tissues to raise insulin-like growth factor 1, which feeds back on the hypothalamus and pituitary. This axis explains both the intended effects on fat distribution and the biological markers used to track them.
| 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 |
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.
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.
Stimulated growth hormone release leads to hepatic production of insulin-like growth factor 1, a key mediator of many growth hormone effects. In clinical studies, tesamorelin increased IGF-1 levels in a dose-dependent manner, although the response varies among individuals. The drug's effect on visceral fat is thought to involve growth hormone-mediated lipolysis and altered adipocyte metabolism. Muscle mass and lean body mass have also been assessed as secondary outcomes, but changes are generally smaller and less consistent than fat reductions.
Pharmacodynamic studies show that tesamorelin reduces visceral adipose tissue more than subcutaneous adipose tissue in the studied population. This selectivity may relate to differences in blood flow and hormone sensitivity between fat depots. Effects on glucose metabolism and insulin sensitivity have been investigated, with some trials reporting modest changes and others showing stability. The precise relationship between growth hormone exposure, IGF-1 levels, and visceral fat loss remains an active area of analysis.
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。
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。
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。
2 FeCl3 + 2 H2O + SO2 → 2 FeCl2 + H2SO4 + 2 HCl 2 CuCl2 + 2 H2O + SO2 → 2 CuCl + H2SO4 + 2 HCl Two less well-known laboratory methods of producing sulfuric acid, albeit in dilute form and requiring some extra effort in purification, rely on electrolysis. A solution of copper(II) sulfate can be electrolyzed with a copper cathode and platinum/graphite anode to give spongy copper at cathode and oxygen gas at the anode. The solution of dilute sulfuric acid indicates completion of the reaction when it turns from blue to clear (production of hydrogen at cathode is another sign):
During the late-1920s, the Rockefeller Foundation created the Medical Sciences Division, which emerged from the former Division of Medical Education. The division was led by Richard M. Pearce until his death in 1930, to which Alan Gregg succeeded him until 1945. During this period, the Division of Medical Sciences made contributions to research across several fields of psychiatry. In 1935 the foundation granted $100000 to the Institute for Psychoanalysis in Chicago. This grant was renewed in 1938, with payments extending into the early-1940s. This division funded women's contraception and the human reproductive system in general, but also was involved in funding controversial eugenics research. Other funding went into endocrinology departments in American universities, human heredity, mammalian biology, human physiology and anatomy, psychology, and the studies of human sexual behavior by Alfred Kinsey. In the interwar years, the foundation funded public health, nursing, and social work in Eastern and Central Europe. In 1950, the foundation expanded their international program of virus research, establishing field laboratories in Poona, India, Trinidad, Belém, Brazil, Johannesburg, South Africa, Cairo, Egypt, Ibadan, Nigeria, and Cali, Colombia, among others. The foundation funded research into the identification of human viruses, techniques for virus identification, and arthropod-borne viruses. Bristol-Myers Squibb, Johns Hopkins University and the Rockefeller Foundation are currently the subject of a $1 billion lawsuit from Guatemala for "roles in a 1940s U.S.
== 19th Century == 1848: Maria Mitchell became the first woman elected to the American Academy of Arts and Sciences; she had discovered a new comet the year before. 1850: Margaretta Morris and Maria Mitchell became the first women elected to the American Association for the Advancement of Science. Morris was a renowned entomologist who specialized in agricultural pests and water beetles, the latter of which was cited by Charles Darwin in his novel On the Origin of Species. 1853: Jane Colden was the only female biologist mentioned by Carl Linnaeus in his masterwork Species Plantarum. 1889: Mary Emilie Holmes became the first female Fellow of the Geological Society of America. 1889: Susan La Flesche Picotte became the first Native American woman to become a physician in the United States. 1893: Florence Bascom became the second woman to earn her Ph.D. in geology in the United States, and the first woman to receive a Ph.D. from Johns Hopkins University. Geologists consider her to be the "first woman geologist in this country [America]." 1896: Florence Bascom became the first woman to work for the United States Geological Survey.
Ancient authors, such as Tacitus and Suetonius, are unanimous about poison having been added to the mushroom dish, rather than the dish having been prepared from poisonous mushrooms. Wasson speculated the poison used to kill Claudius was derived from death caps, with a fatal dose of an unknown poison (possibly a variety of nightshade) being administered later during his illness. Other historians have speculated that Claudius may have died of natural causes. In the 2023 Leongatha mushroom murders, Australian woman Erin Patterson was found guilty of three murders and one attempted murder of members of her estranged husband's family by serving them beef Wellingtons that contained A. phalloides. Three of the four guests died within days of the meal, while one survived after weeks in a coma.
Sources: en.wikipedia.org
Abelacimab (MAA868), is a fully human monoclonal antibody for the treatment of thrombosis, under development by Anthos Therapeutics. It is anti-factor XI antibody. The hope behind its development is that factor XI plays a bigger role in thrombosis (via the intrinsic/contact activation pathway) than hemostasis, so targeting it might reduce clotting risks without a corresponding increase in bleeding. It has, indeed, shown overwhelming reduction in bleeding as compared to a direct oral anticoagulant (rivaroxaban) in patients with atrial fibrillation and a moderate-to-high risk of stroke. Data is insufficient for drawing a conclusion on whether it increases or decreases stroke events as compared to rivaroxaban. Antibody Monoclonal antibody Immunology
DNA usually occurs as linear chromosomes in eukaryotes, and circular chromosomes in prokaryotes. The set of chromosomes in a cell makes up its genome; the human genome has approximately 3 billion base pairs of DNA arranged into 46 chromosomes. The information carried by DNA is held in the sequence of pieces of DNA called genes. Transmission of genetic information in genes is achieved via complementary base pairing. For example, in transcription, when a cell uses the information in a gene, the DNA sequence is copied into a complementary RNA sequence through the attraction between the DNA and the correct RNA nucleotides. Usually, this RNA copy is then used to make a matching protein sequence in a process called translation, which depends on the same interaction between RNA nucleotides. In an alternative fashion, a cell may copy its genetic information in a process called DNA replication. The details of these functions are covered in other articles; here the focus is on the interactions between DNA and other molecules that mediate the function of the genome.
The drug has been introduced for use in executions by lethal injection in certain jurisdictions in the United States in combination with other drugs. It was introduced to replace pentobarbital after the latter's manufacturer disallowed that drug's use for executions. Midazolam acts as a sedative, resulting in the prisoner being in a state of deep anesthesia comparable to that experienced during surgery. One or more other drugs are usually used to stop the prisoner's heart, rendering them medically dead. Midazolam has been used as part of a three-drug cocktail with vecuronium bromide and potassium chloride in Florida and Oklahoma prisons and has also been used along with hydromorphone in a two-drug protocol in Ohio and Arizona.
=== Off-label drugs === Acetazolamide (Diamox) – carbonic anhydrase inhibitor Atomoxetine (Strattera) – norepinephrine reuptake inhibitor (NRI) Eszopiclone (Lunesta) – GABAA receptor positive allosteric modulator and nonbenzodiazepine/Z-drug Oxybutynin (Ditropan) – muscarinic acetylcholine receptor antagonist (anticholinergic) Pimavanserin (Nuplaizid) – serotonin 5-HT2A receptor antagonist Sodium oxybate (GHB; Xyrem) – GABAB receptor agonist and GHB receptor agonist Trazodone (Desyrel) – various actions Weight-loss drugs (e.g., liraglutide, semaglutide) – obesity-related sleep apnea
==== Zwitterionic surfactants ==== Zwitterionic (ampholytic) surfactants have both cationic and anionic centers attached to the same molecule. The cationic part is based on primary, secondary, or tertiary amines or quaternary ammonium cations. The anionic part can be more variable and include sulfonates, as in the sultaines CHAPS (3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate) and cocamidopropyl hydroxysultaine. Betaines such as cocamidopropyl betaine have a carboxylate with the ammonium. The most common biological zwitterionic surfactants have a phosphate anion with an amine or ammonium, such as the phospholipids phosphatidylserine, phosphatidylethanolamine, phosphatidylcholine, and sphingomyelins. Lauryldimethylamine oxide and myristamine oxide are two commonly used zwitterionic surfactants of the tertiary amine oxides structural type.
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 mimics a natural hypothalamic signal that tells the pituitary to release growth hormone. The result is a rise in circulating growth hormone and, indirectly, in insulin-like growth factor 1. Over weeks of treatment this shift is associated with a selective decrease in fat stored inside the abdomen.