If you have been reading about acetylated peptide and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Last reviewed on 2026-02-04. Where a claim depends on a specific study, the study is described rather than over-claimed.
Thymosin alpha 1 is a 28-amino-acid peptide first isolated from thymosin fraction 5, a bovine thymic extract. Its sequence begins with an acetylated serine residue and carries a high proportion of acidic residues, so the molecule has a net negative charge near neutral pH. Despite the shared name, it is unrelated in sequence to the thymosin beta family. Synthetic material prepared by solid-phase peptide synthesis is identical in sequence to the natural peptide.
Several names appear in the literature for this peptide, including thymalfasin and the abbreviation T-alpha-1. Naming conventions differ among research articles, regulatory documents, and supplier catalogs, which complicates literature searches. Both synthetic and recombinant production routes yield a peptide with the same 28-residue sequence as the thymic isolate. Because the thymosin label also covers unrelated peptides, sources should be compared by sequence rather than by name alone.
在信号层面，Tα1可能通过Toll样受体等模式识别受体发挥作用。部分实验显示，它能激活髓样分化因子88依赖的通路，进而促进核因子κB进入细胞核。这导致白细胞介素2、干扰素γ和白细胞介素12等细胞因子的转录增加。这些细胞因子偏向辅助性T细胞1型应答，有助于细胞免疫。然而，具体受体和结合位点尚未完全确定，不同实验模型的结果存在差异。
临床研究将Tα1用于慢性病毒感染、肿瘤辅助治疗和疫苗佐剂等场景。部分试验报告了免疫学指标改善，但临床终点获益在不同研究中并不一致。系统综述指出，研究间在人群、剂量和联合方案上差异较大，难以汇总结论。因此，Tα1的确切临床地位仍属开放问题，需要更多高质量随机对照试验来澄清。其机制研究也需从体外实验向体内模型推进。
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C129H215N33O55 | Calculated for the acetylated 28-residue peptide |
| Appearance | White to off-white powder | Lyophilized solid recovered from aqueous buffer |
| Solubility | Freely soluble in water | Typically dissolved in water or buffer before use |
| Typical storage | -20 C or below, desiccated | Protect from light and avoid repeated freeze-thaw cycles |
| Identity testing | Reverse-phase HPLC with mass spectrometry | Retention time and measured mass confirm the sequence |
Lyophilized thymosin alpha 1 is typically stored refrigerated at 2 to 8 degrees Celsius and kept away from light. Reconstituted solutions are less stable and are usually used promptly after preparation. Repeated freeze-thaw cycles are avoided because they can promote aggregation and loss of activity. The peptide adsorbs to some plastic and glass surfaces, so a carrier protein is often added to dilute working solutions. Manufacturer instructions and published protocols both govern handling.
Identity and purity testing for thymosin alpha 1 relies mainly on reversed-phase high-performance liquid chromatography and mass spectrometry. Chromatography separates the parent peptide from truncated or modified variants, while mass spectrometry confirms the expected molecular mass. Amino acid analysis and peptide mapping provide additional sequence confirmation. Counterion content, water content, and residual solvents are measured separately as part of specification testing. No single method captures every attribute, so laboratories combine several techniques.
The peptide lacks cysteine, methionine, and tryptophan, so disulfide scrambling and sulfur oxidation are not major degradation routes. Instead, aspartate residues can undergo isomerization or cyclization to succinimide intermediates, generating isoaspartate variants. Hydrolysis of peptide bonds also occurs slowly in solution. These changes may reduce biological activity even when the main peak remains detectable. Stability studies therefore track both potency and the appearance of related substances.
Routine handling calls for storage of the lyophilized powder at refrigerated temperatures, away from light, in a sealed container. Working solutions are often prepared in sterile water or buffer and kept cold between uses. Repeated freeze-thaw cycles are generally avoided because they can promote aggregation and loss of material. Laboratories usually record lot number, reconstitution date, and storage conditions so that any change in behavior can be traced to a specific preparation.
Reverse-phase high-performance liquid chromatography is the standard technique for assessing purity and concentration, because the peptide's hydrophobicity allows clean separation from related impurities. Mass spectrometry confirms molecular identity and detects sequence errors or truncations. Amino acid analysis and peptide mapping supply additional structural confirmation when required. Chromatographic purity values reported on certificates of analysis describe the proportion of the main peak and do not by themselves establish biological activity.
Like most short peptides, thymosin alpha-1 is susceptible to hydrolysis under strongly acidic or basic conditions and to oxidation when exposed to air over long periods. The acetylated amino terminus blocks one common degradation route, which contributes to the molecule's relative robustness in solution. Lyophilized material generally retains potency for extended periods when kept cold and dry. Once reconstituted, aqueous solutions are less stable and are typically used within a defined window rather than held indefinitely at ambient temperature.
The HSQC experiment is also useful for detecting binding interface in protein-protein interaction, as well the interactions with ligands such as drugs. By comparing the HSQC of the free protein with the one bound to the ligand, changes in the chemical shifts of some peaks may be observed, and these peaks are likely to lie on the binding surface where the binding perturbed their chemical shifts. The 15N HSQC may also be used in relaxation analysis in the studies of molecular dynamics of proteins, the determination of ionization constant, and other studies.
== Side effects == Tetryzoline eye drops may cause blurred vision, eye irritation and dilated pupils. Tetryzoline is not suitable for prolonged use as its vasoconstrictive effects within the eye eventually decrease or stop. If tolerance to the drug has developed, ceasing its use may cause a rebound effect and increase redness of the eyes — a vasodilatory effect. Intranasal use of tetryzoline may cause transient burning, stinging, or dryness of the mucosa and sneezing. Prolonged intranasal use often causes opposite effects in the form of rebound congestion with effects such as chronic redness, swelling and rhinitis. Prolonged use thus may result in overuse of the drug. In children, it might cause profound sedation.
=== Names === Etilefrine is the generic name of the drug and its INNTooltip International Nonproprietary Name and BANTooltip British Approved Name, while étiléfrine is its DCFTooltip Dénomination Commune Française and etilefrina is its DCITTooltip Denominazione Comune Italiana. In the case of the hydrochloride salt, its generic name is etilefrine hydrochloride and this is its BANMTooltip British Approved Name and JANTooltip Japanese Accepted Name. Synonyms of etilefrine include ethylnorphenylephrine, ethylphenephrine, etiladrianol, aethyladrianol, and M-I-36. Brand names of the drug include Effortil, Circupon, Apocretin, Palsamin, Kertasin, Pressoton, Effoless, and Sanlephrin.
== Signs and symptoms == Skin: The pigment is deposited throughout the skin, but only becomes apparent in certain locations, where the concentration is great enough to be seen clinically. This usually occurs in areas where connective tissue is thick (joints, tympanic membrane) or close to the surface of the skin (thenar and hypothenar eminences and the sides of the fingers). In exogenous ochronosis, the hyperpigmentation is localized to the area where the inciting agent is applied. Intradermal nevi can appear like blue nevi. Eye: Ocular manifestations are frequent in patients with ochronosis; most commonly hyperpigmentation of the sclera, primarily observed symmetrically to both sides of the cornea within the palpebral fissure. Furthermore, brown pigment spots in the limbus are generally considered pathognomonic. These ocular signs generally occur early in the development of the disease and can serve as a valuable diagnostic feature of the disease. Cartilage: Darkening and hardening of ear cartilage is a prominent feature of ochronosis. Nasal cartilage is also frequently involved. The voice can be affected by hardening of the laryngeal cartilage. Stiffening of the ribs with decreased lung function has also been reported. The intervertebral cartilage is also more prone to herniation. Connective tissue: Hardening of tendons and ligaments can predispose them to rupture. Color changes in the joints can be observed clinically. Arthropathy is common due to chronic inflammation and microruptures.
Sources: en.wikipedia.org
=== Naming === Using Mendeleev's nomenclature for unnamed and undiscovered elements, darmstadtium should be known as eka-platinum. In 1979, IUPAC published recommendations according to which the element was to be called ununnilium (with the corresponding symbol of Uun), a systematic element name as a placeholder, until the element was discovered (and the discovery then confirmed) and a permanent name was decided on. Although widely used in the chemical community on all levels, from chemistry classrooms to advanced textbooks, the recommendations were mostly ignored among scientists in the field, who called it "element 110", with the symbol of E110, (110) or even simply 110. In 1996, the Russian team proposed the name becquerelium after Henri Becquerel. The American team in 1997 proposed the name hahnium after Otto Hahn (previously this name had been used for element 105). The name darmstadtium (Ds) was suggested by the GSI team in honor of the city of Darmstadt, where the element was discovered. The GSI team originally also considered naming the element wixhausium, after the suburb of Darmstadt known as Wixhausen where the element was discovered, but eventually decided on darmstadtium. Policium had also been proposed as a joke due to the emergency telephone number in Germany being 1–1–0. The new name darmstadtium was officially recommended by IUPAC on August 16, 2003.
== Interpretation == One study reviewed the relative diagnostic value of enzyme and bicarbonate concentrations compared with enzyme output in 363 secretin-CCK tests. The investigators also evaluated the requirement for perfusion markers to accurately quantify volume, and the validity of a shortened sampling time (first 20 minutes). Only 60 percent of volume was recovered with the duodenal aspiration tube, suggesting that marker perfusion to correct for distal loss of secretion is important to accurately quantify volume. Using a trypsin output <50 U/kg/h as the reference standard, measurement of enzyme concentration alone misclassified approximately 10 percent of patients. Use of a shortened collection time misclassified approximately 4 percent of patients. The authors concluded that this was an unacceptably high rate of misclassification and that the standard prolonged collection of fluid using a perfusion marker must be performed to accurately measure exocrine function.
== Use == The Tatra Shepherd Dog was traditionally used as a flock guardian dog, to deter predators from attacking flocks of sheep in the mountainous terrain of the Podhale region. In modern Poland it is most often kept either as a guard dog or as a companion animal.
Sources: en.wikipedia.org
Medical reports describing individuals affected by FOP date back to Dr. Guy Patin in 1648. FOP was originally called myositis ossificans progressiva and was thought to be caused by muscular inflammation (myositis) that caused bone formation. In 1736, London surgeon, John Freke wrote the first case report of FOP, describing a 14-year-old boy that exhibited "'many large swellings on his back, that arise from all the vertebrae of the neck and reach down to the os sacrum. They likewise arise from every rib of his body, and joining together in all parts of his back, as the ramifications of coral do, they make, as it were, a fixed bony pair of bodice." The disease was renamed by Victor A. McKusick in 1970 following the discovery that soft tissue other than muscles (e.g. ligaments) were also affected by the disease process. The best known FOP case is that of Harry Eastlack (1933–1973). His condition began to develop at the age of ten, and by the time of his death from pneumonia in November 1973, six days before his 40th birthday, his body had completely ossified, leaving him able to move only his lips. Eastlack never met another person with FOP during his lifetime. Eastlack donated his body to science and his skeleton is now at the Mütter Museum in Philadelphia, and has proven to be an invaluable source of information in the study of FOP. Another person with FOP, Carol Orzel (April 20, 1959 – February 2018), also donated her body to the museum. Her skeleton was placed on exhibit there, adjacent to Eastlack's, in February 2019.
Peptide mass fingerprinting (PMF), also known as protein fingerprinting, is an analytical technique for protein identification in which the unknown protein of interest is first cleaved into smaller peptides, whose absolute masses can be accurately measured with a mass spectrometer such as MALDI-TOF or ESI-TOF. The method was developed in 1993 by several groups independently. The peptide masses are compared to either a database containing known protein sequences or even the genome. This is achieved by using computer programs that translate the known genome of the organism into proteins, then theoretically cut the proteins into peptides, and calculate the absolute masses of the peptides from each protein. They then compare the masses of the peptides of the unknown protein to the theoretical peptide masses of each protein encoded in the genome. The results are statistically analyzed to find the best match. The advantage of this method is that only the masses of the peptides have to be known. A disadvantage is that the protein sequence has to be present in the database of interest. Additionally most PMF algorithms assume that the peptides come from a single protein. The presence of a mixture can significantly complicate the analysis and potentially compromise the results. Typical for the PMF-based protein identification is the requirement for an isolated protein. Mixtures exceeding a number of 2–3 proteins typically require the additional use of MS/MS-based protein identification to achieve sufficient specificity of identification.
=== Carboplatin === Pemetrexed is also recommended in combination with carboplatin and pembrolizumab for the first-line treatment of advanced non-small cell lung cancer. However, the relative efficacy or toxicity of pemetrexed-cisplatin versus pemetrexed-carboplatin has not been established beyond what is generally thought about cisplatin or carboplatin doublet drug therapy.
=== Forked connectivity === HDMI has supported Consumer Electronics Control (CEC) commands since the first version. The CEC bus allows connecting multiple sources to a single display, and controlling any of these devices from any remote. DisplayPort 1.3 added the possibility of transmitting CEC commands over the AUX channel. On the other hand, DisplayPort supports connecting multiple displays to one DP port via the Multi-Stream Transport (MST) feature, allowing a single computer to have multiple displays. These differences reflects the origins the two standards, and the priorities of their authors. HDMI originates from consumer electronics companies, whereas DisplayPort is owned by VESA, which started as an organization for computer standards.
Sources: en.wikipedia.org
It is a 28-amino-acid peptide originally purified from a bovine thymic extract and later produced synthetically. It is studied mainly for its effects on immune cell function.
No. The two peptides share part of a name but differ in length, sequence, and net charge. Literature searches that treat them as one compound return misleading results.
Solid-phase peptide synthesis is the usual route, and recombinant expression has also been described. Both approaches produce material matching the natural sequence.
它促进未成熟T细胞分化并增强成熟T细胞的增殖与细胞因子分泌。这些作用有助于放大抗原特异性免疫应答。