The short version of prohibited list fits in a sentence. The long version — which is the one that helps — is below.
This page was last updated on 2026-06-15 and is reviewed periodically as new material appears.
Practical handling centers on limiting moisture, oxygen, and temperature excursions. Lyophilized material is generally held at or below minus twenty degrees Celsius, protected from light and kept sealed until use. Once reconstituted, solutions are typically kept cold and used within a short window because hydrolysis and microbial growth both accelerate in liquid form. Repeated freeze-thaw cycles are avoided, since they promote aggregation. Vial contents should be inspected for particulates and clarity before analysis, and working aliquots are prepared to reduce the number of times the stock is opened.
Quantitation of the peptide relies mainly on reversed-phase high-performance liquid chromatography with ultraviolet detection, typically at 214 nanometers, where the peptide bond absorbs. Identity is confirmed by mass spectrometry, most often electrospray ionization coupled to liquid chromatography, and by peptide mapping after enzymatic digestion. Because related impurities differ only slightly in sequence or modification, method development emphasizes resolution rather than speed. Purity is usually reported as a percentage of the main peak area, with individual impurities listed separately when they exceed a defined reporting threshold.
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。
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。
| Property | Value | Notes |
|---|---|---|
| Routine purity assay | Reversed-phase HPLC | Ultraviolet detection near 214 nm |
| Identity confirmation | Liquid chromatography–mass spectrometry | Mass shift reveals modification or truncation |
| Typical purity specification | Greater than 95 percent | Reported as main-peak area percentage |
| Long-term storage | Minus 20 degrees Celsius or colder | Sealed, protected from light |
| Principal degradation routes | Oxidation, deamidation, aggregation | Monitored individually during stability studies |
Lyophilized material is typically held under refrigeration between two and eight degrees Celsius, shielded from light and ambient moisture. Peptides of this size adsorb to glass and plastic, so working procedures often call for low-binding containers and as few transfers as possible. Absorbed water during weighing shifts the apparent mass of a sample, and controlling room humidity reduces that source of error. Once dissolved, solutions are kept cold and used within the interval printed on the accompanying label or certificate. Degradation accelerates markedly in dilute aqueous form.
Identity and purity are judged through a combination of chromatographic and mass spectrometric techniques. Reversed-phase high-performance liquid chromatography separates the intact peptide from truncated, oxidized, and deamidated variants, and the resulting peak-area percentages yield a purity figure. Electrospray ionization mass spectrometry confirms the expected molecular mass and can expose unanticipated modifications. Amino acid analysis and peptide mapping support sequence fidelity, while water content, pH, sterility, and bacterial endotoxin testing describe the physical and microbiological attributes of a finished lot.
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.
Tesamorelin is a synthetic peptide analog of growth hormone-releasing hormone (GHRH). Its sequence corresponds to the 44-amino-acid form of human GHRH with a trans-3-hexenoyl group attached to the N-terminal tyrosine. This modification slows enzymatic cleavage and extends the peptide's activity relative to the native hormone. The compound is produced by solid-phase peptide synthesis and supplied as a lyophilized powder. Researchers classify it as a GHRH receptor agonist. Its structure places it in the same family as other growth hormone secretagogues that act on the pituitary.
The peptide is supplied as a lyophilized powder in single-use vials and is normally kept refrigerated between two and eight degrees Celsius, protected from light. Once dissolved, the solution is handled carefully because peptide bonds and the acyl modification can degrade under warm or alkaline conditions. Vials are inspected for cracks, and the powder is checked for color and uniformity before handling. Temperature excursions during shipping are a frequent reason for quality questions.
Identity and purity are assessed with reversed-phase high-performance liquid chromatography, which separates the peptide from truncated or oxidized forms. Mass spectrometry confirms the expected molecular weight, and peptide mapping after enzymatic digestion verifies the amino acid sequence. Water content is measured because residual moisture affects stability, and tests for aggregates or particulates are standard for injectable peptides. Circular dichroism can indicate whether the molecule has adopted an unexpected secondary structure in solution.
Research supply is often accompanied by a certificate of analysis listing chromatographic purity, mass confirmation, and storage conditions. Laboratories compare that document with an independent test when material is intended for bench work, since certificates describe a batch rather than an individual vial. Published studies usually state the source and purity of the peptide because small differences in purity can shift measured activity. Full analytical validation is rarely reported, which leaves batch-to-batch comparability an open question.
Gene therapy is a promising treatment for a number of diseases where a "normal" gene carried by the vector is inserted into the genome, to replace an "abnormal" gene or supplement the expression of particular gene. Viral vectors are generally used but other nonviral methods of delivery are being developed. The treatment is still a risky option due to the viral vector used which can cause ill-effects, for example giving rise to insertional mutation that can result in cancer. However, there have been promising results. Expression vectors are fundamental tools in molecular biology and biotechnology for directing the expression of cloned genes in host cells, enabling the study of gene function and the production of recombinant proteins. Due to their widespread use in research, reference expression vectors are preserved by public biological resource centres and non-profit repositories, facilitating access to standardized materials for scientists worldwide; such repositories include BCCM/GeneCorner and Addgene.
In 1981 Channon left Guy's Hospital to continue his work with Drs Martin Hartog and Richard Paisey at the Bristol Royal Infirmary. Channon then developed the miniature Portaject device. Unlike the Multiject the Portaject is designed to be worn. It has the capacity for sufficient insulin for 24 hours (at the time insulin had to be refrigerated; at room or body temperature it would become unusable after 24 hours). Channon self-funded the design and fabrication work through his company Channon Medical Ltd. He filed a patent for the Portaject in 1988 but subsequently withdrew the application, choosing instead to donate his research to the field. Clinical trials at the BRI were supported by a small grant of £4,500 from the National Medical Research fund. Dr Hartog attests that "Portaject was the first device that allowed convenient repeated subcutaneous injections of insulin and led to the Novopen. Administration of insulin in this way resulted in a much improved control of the patient's diabetes and, consequently, to a considerably improved prognosis overall". Dr Paisey recalls that clinical trials were conducted with 20 patients and that "one of them continued for 20 years with the same device and achieved good glycemic control. He also designed and manufactured a belt to house the pump". Another long term user, Stephen Dixon, wrote to Channon "Thanks so much for doing what you did. You truly helped transform millions of lives, including mine". In 1989 Channon developed a simple device for protecting, lubricating and sterilizing a hypodermic needle.
The oldest known parish register in Paris belongs to the parish of Saint-Jean-en-Grève. In agenda format and written in Latin, it covers the period from April 1515 to November 1521. Registers of baptisms were opened as early as 1525 in the parishes of Saint-André-des-Arts and Saint-Jacques-la-Boucherie. The first burial registers, from Saint-Josse and Saint-Landry, date back to 1527. In August 1539, Francis I issued the Ordinance of Villers-Cotterêts, requiring parish priests to keep a register of baptisms conducted in their church, written in French (Article 51):
=== Metabolism === P. aeruginosa is a facultative anaerobe, as it is well adapted to proliferate in conditions of partial or total oxygen depletion. This organism can achieve anaerobic growth with nitrate or nitrite as a terminal electron acceptor. When oxygen, nitrate, and nitrite are absent, it is able to ferment arginine and pyruvate by substrate-level phosphorylation. Additionally, phenazines produced by P. aeruginosa can act as electron shuttles to facilitate survival of cells at depth in biofilms. Adaptation to microaerobic or anaerobic environments is essential for certain lifestyles of P. aeruginosa, for example, during lung infection in cystic fibrosis and primary ciliary dyskinesia, where thick layers of lung mucus and bacterially-produced alginate surrounding mucoid bacterial cells can limit the diffusion of oxygen. P. aeruginosa growth within the human body can be asymptomatic until the bacteria form a biofilm, which overwhelms the immune system. These biofilms are found in the lungs of people with cystic fibrosis and primary ciliary dyskinesia, and can prove fatal.
Sources: en.wikipedia.org
== Historical background == For almost 50 years molecular biology was based on two dogmas: (i) equating biological function of the protein with a unique three-dimensional structure and (ii) assuming exquisite specificity in protein complexes. Specificity/selectivity is ensured by unambiguous set of interactions formed between the protein and its ligand (another protein, DNA, RNA or small molecule). Many protein complexes however, contain functionally important/critical regions, which remain highly dynamic in the complex or adopt different conformations. This phenomenon is defined fuzziness. The most pertinent example is the cyclin-dependent kinase inhibitor Sic1, which binds to the SCF subunit of Cdc4 in a phosphorylation dependent manner. No regular secondary structures are gained upon phosphorylation and the different phosphorylation sites interchange in the complex.
==== Single-drug formulations ==== Adapalene (CD-271; Differin) – retinoid (retinoic acid receptor agonist) Azelaic acid (BAY39-6251; Finacea; Skinoren) – undefined mechanism of action Benzoyl peroxide (Bepio; M6050; M605101) – undefined mechanism of action Clascoterone (Breezula; Winlevi; CB-03-01; cortexolone 17α-propionate) – antiandrogen (androgen receptor antagonist) Clindamycin (ResiDerm A; Zindaclin) – lincosamide antibiotic Dapsone topical (Aczone; Atrisone) – sulfone antibiotic Doxycycline hyclate (Acticlate; Monodox; AQ101) – tetracycline antibiotic Isotretinoin (Absorica; Accutane; CIP-isotretinoin; Epuris; Lisacne-CIP) – retinoid (retinoic acid receptor agonist) Minocycline (DFD-10; DFD-29; Emrosi; Minolira) – tetracycline antibiotic Minocycline foam (Amzeeq; FMX-102; FMX-103; FMX-101; FXFM-244; Zilxi) – tetracycline antibiotic Nadifloxacin topical – fluoroquinolone antibiotic Ozenoxacin (Dubine; GF-001001-00; M-5120; M-512101; M-512102; Ozadub; Ozanex; T-3912; Xepi; Zebiax) – quinolone antibiotic Sarecycline (Seysara; P-0005672; WC-3035) – narrow-spectrum tetracycline antibiotic Solubilised benzoyl peroxide (CLENZIderm M.D.; SoluCLENZ Rx Gel) – undefined mechanism of action Tazarotene topical (AGN-190299; Avage; Fabior; Suretin; Tazorac; Zorac) – retinoid (retinoic acid receptor agonist) Tretinoin (Acnisdin Retinoico; All-trans retinoic acid; Arotinoid; Avita; Dermojuventus; Loderm Retinoico; NSC 122758; Retinoic acid; Retirides; Vesanoid; Vitamin A acid; Vitamin-A Acid; Vitanol) – retinoid (retinoic acid receptor agonist) Tretinoin lotion (Altreno; IDP-121) – retinoid (retinoic acid receptor agonist) Trifarotene (Aklief; CD-5789) – retinoid acid receptor gamma (RAR-γ) agonist
Pests such as insects have been transported to new habitats through the trade in fresh produce and significantly affected agricultural production and the environment once they established themselves. To reduce this threat and enable trade across quarantine boundaries, food is irradiated using a technique called phytosanitary irradiation. Phytosanitary irradiation sterilizes the pests preventing breeding by treating the produce with low doses of irradiation (less than 1000 Gy). The higher doses required to destroy pests are not used due to either affecting the look or taste, or cannot be tolerated by fresh produce.
Sources: en.wikipedia.org
After the completion of the coupling reaction, a small percentage of the solid support-bound 5'-OH groups (0.1 to 1%) remains unreacted and needs to be permanently blocked from further chain elongation to prevent the formation of oligonucleotides with an internal base deletion commonly referred to as (n-1) shortmers. The unreacted 5'-hydroxy groups are, to a large extent, acetylated by the capping mixture. It has also been reported that phosphoramidites activated with 1H-tetrazole react, to a small extent, with the O6 position of guanosine. Upon oxidation with I2 /water, this side product, possibly via O6-N7 migration, undergoes depurination. The apurinic sites thus formed are readily cleaved in the course of the final deprotection of the oligonucleotide under the basic conditions (see below) to give two shorter oligonucleotides thus reducing the yield of the full-length product. The O6 modifications are rapidly removed by treatment with the capping reagent as long as the capping step is performed prior to oxidation with I2/water. The synthesis of oligonucleotide phosphorothioates (OPS, see below) does not involve the oxidation with I2/water, and, respectively, does not suffer from the side reaction described above. On the other hand, if the capping step is performed prior to sulfurization, the solid support may contain the residual acetic anhydride and N-methylimidazole left after the capping step.
When the elastic fibers are relaxed the elastic chains appear disorganized, when tensile pressure is give the elastic chains appear organized and return to a disorganized state when the pressure is released. Collagen fibers form networks to provide strength and structural framework for the molecules within the extracellular matrix.
Significant controversy surrounds female genital mutilation, with the World Health Organization (WHO) and other health organizations campaigning against the procedures on behalf of human rights, stating that it is "a violation of the human rights of girls and women" and "reflects deep-rooted inequality between the sexes". Female genital mutilation has existed at one point or another in almost all human civilizations, most commonly to exert control over the sexual behavior, including masturbation, of girls and women. It is carried out in several countries, especially in Africa, and to a lesser extent in other parts of the Middle East and Southeast Asia, on girls from a few days old to mid-adolescent, often to reduce sexual desire in an effort to preserve vaginal virginity. Comfort Momoh stated it may be that female genital mutilation was "practiced in ancient Egypt as a sign of distinction among the aristocracy"; there are reports that traces of infibulation are on Egyptian mummies. Custom and tradition are the most frequently cited reasons for the practice of female genital mutilation. Some cultures believe that female genital mutilation is part of a girl's initiation into adulthood and that not performing it can disrupt social and political cohesion. In these societies, a girl is often not considered an adult unless she has undergone the procedure.
In broad terms, spent nuclear fuel has three main components. The first consists of fission products, the leftover fragments of fuel atoms after they have been split to release energy. Fission products come in dozens of elements and hundreds of isotopes, all of them lighter than uranium. The second main component of spent fuel is transuranics (atoms heavier than uranium), which are generated from uranium or heavier atoms in the fuel when they absorb neutrons but do not undergo fission. The actinide series on the periodic table runs from actinium to lawrencium and includes uranium as well as transuranic elements. The third and largest component is the remaining uranium which is around 98.25% uranium-238, 1.1% uranium-235, and 0.65% uranium-236. The U-236 comes from the non-fission capture reaction where U-235 absorbs a neutron but releases only a high energy gamma ray instead of undergoing fission. The physical behavior of the fission products is markedly different from that of the actinides. In particular, fission products do not undergo fission and therefore cannot be used as nuclear fuel. Indeed, because fission products are often neutron poisons (absorbing neutrons that could be used to sustain a chain reaction), fission products are viewed as nuclear 'ashes' left over from consuming fissile materials. Furthermore, only seven long-lived fission product isotopes have half-lives longer than a hundred years, which makes their geological storage or disposal less problematic than for transuranic materials.
Sources: en.wikipedia.org
Reversed-phase high-performance liquid chromatography with ultraviolet detection is the standard technique for purity and content. Mass spectrometry provides orthogonal confirmation of identity. The two are normally used together rather than in isolation.
Removing water slows hydrolysis and limits the mobility that drives aggregation. A dry powder is also less hospitable to microbial growth. These factors make cold storage of the solid form more forgiving than storage of a reconstituted solution.
Methionine oxidation, asparagine and glutamine deamidation, and non-covalent or covalent aggregation are the main routes reported for peptides of this class. Each is tracked as a separate impurity. Their relative abundance depends on formulation and storage history.
特沙莫瑞林是国际非专利名称,指一种经过 N 端修饰的生长激素释放激素类似物。它被归类为合成肽,序列与 GHRH(1-44) 密切相关。该名称不指代任何特定品牌或剂型。