A practical reference on Lyophilisation: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2025-12-02 and is reviewed periodically as new material appears.
Scientific literature on semax is unevenly distributed. A substantial share of published work originates from a small number of laboratories in Russia, while independent replication elsewhere is limited. Human data consist mostly of small trials with short follow-up, and several reported outcomes rely on subjective rating scales. Questions about how much intact peptide reaches the central nervous system after nasal administration, and how long it persists there, are still unresolved. The compound is best described as an active research subject rather than a settled pharmacological agent.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It was derived from the ACTH(4-10) fragment, a short segment of adrenocorticotropic hormone that lacks the hormonal activity associated with the full-length peptide. Researchers at the Institute of Molecular Genetics in Moscow developed the compound during the 1980s. It has been registered as a pharmaceutical product in Russia and several neighbouring countries, where it is supplied as a nasal solution, and it is also sold internationally as a research chemical.
纯度评估以反相高效液相色谱为主，通过主峰面积百分比给出粗略结果，再配合电喷雾质谱核对分子量。氨基酸分析可验证组成比例，手性色谱或毛细管电泳用于检查残基构型。常见杂质包括缺失序列的短肽、氧化产物与二聚体。由于多数市售品不附带完整检验报告，独立第三方检测常被用来核实标称值。
从分子层面看，Semax 是线性七肽，没有二硫键、糖基或脂链修饰，N 端为游离氨基，C 端为游离羧基。分子含组氨酸与谷氨酸侧链，因此在水和甲醇等极性溶剂中溶解良好，在非极性溶剂中溶解有限。计算分子量约为 814 Da，与其质子化离子的质荷比吻合，可用于质谱确认。
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Calculated for the free peptide |
| Molar mass | 813.9 g/mol | Anhydrous free base |
| Peptide class | Synthetic heptapeptide | ACTH(4-10) analogue |
| Parent fragment | ACTH(4-10) | Adrenocorticotropic hormone segment |
| Developmental origin | Institute of Molecular Genetics, Moscow | Work began in the 1980s |
Russian regulatory authorities approved the peptide for nasal administration, and it remains listed in the national pharmacopoeia under several trade names. Documented indications include acute ischemic stroke, transient ischemic attacks, traumatic brain injury, and certain ophthalmological and neurological conditions. Physicians also prescribe it for cognitive complaints in older patients, although the evidence base for that use is thinner. Outside Russia and a few neighboring states, the substance is not an approved medicine and is sold instead as a research chemical.
Later generations of the molecule include an N-acetylated form and an amidated form, both marketed online alongside the parent peptide. These variants differ in terminal chemistry and stability, and they are frequently discussed in the same breath even though they have not been compared in controlled trials. Supply outside formal healthcare systems comes largely from laboratories that synthesize peptides to order. Purity and identity of these materials vary widely, and no single body oversees the international trade.
Semax is a synthetic heptapeptide developed in the Soviet Union during the 1980s by researchers at the Institute of Molecular Genetics in Moscow. It was designed as a truncated analog of adrenocorticotropic hormone, retaining only the fragment spanning residues four through ten. Investigators sought a peptide that would preserve the cognitive effects associated with ACTH while eliminating the hormonal stimulation of the adrenal cortex. The compound entered clinical use in Russia during the following decade.
Published research has focused mainly on neurological and cognitive endpoints in animal models, with proposed mechanisms involving brain-derived neurotrophic factor and related signalling pathways. A substantial share of the human data originates from a limited number of research groups, and independent replication in other countries remains sparse. Regulatory status reflects that distribution: the peptide is registered as a medicine in Russia and appears in some neighbouring markets, while elsewhere it is handled as a research chemical without approved therapeutic labelling. Questions about dose-response relationships, long-term effects, and comparability across studies are still open.
Lyophilised powder is normally kept at -20 °C in a desiccated container, with some suppliers recommending -80 °C for long-term archival storage. Repeated freeze-thaw cycles are the most common cause of avoidable loss, so aliquoting before freezing reduces variability between working sessions. Dissolved peptide is far less stable than the dry solid and is usually prepared fresh or held briefly at 4 °C. Aqueous solutions support both hydrolysis of the backbone and oxidation of the N-terminal methionine, and these two routes dominate degradation under ordinary laboratory conditions.
Clinical evidence consists largely of small trials with modest sample sizes, often without independent replication. Reported endpoints include cognitive scores, recovery after stroke, and visual function, but study designs vary widely and few trials meet contemporary reporting standards. Systematic reviewers have noted a high risk of bias in several of these reports. No large multicenter trial conducted outside Russia has been published. The compound is therefore best described as investigational in most jurisdictions, with its clinical role still unresolved.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Its chain combines the first seven residues of corticotropin with a C-terminal proline-glycine-proline extension, a modification intended to slow enzymatic breakdown. The free peptide has a molecular mass near 813.9 daltons. It belongs to the class of ACTH-derived fragments studied for central nervous system activity rather than for adrenal steroid stimulation. This structural relationship to a natural hormone fragment is the usual starting point for describing the compound in the literature.
Material sold for laboratory use varies widely in stated purity and documentation. A certificate of analysis should list the analytical method, the column and detector used, and the observed purity value. Independent verification by an outside laboratory is the practical way to confirm identity when documentation is absent or internally inconsistent. Regulatory status differs by country, and a product legal in one jurisdiction may be unapproved or controlled in another.
Identity and purity of semax are established with reversed-phase high-performance liquid chromatography coupled to ultraviolet detection, usually at 214 nanometres. Mass spectrometry, most often electrospray ionisation in positive mode, confirms the molecular mass and reveals truncated sequences. Amino acid analysis and peptide mapping after enzymatic digestion provide additional structural confirmation. Laboratories typically report purity as the percentage area of the main peak, a figure that does not capture isomeric or oxidised variants unless the method resolves them.
The peptide is prone to several degradation pathways. Oxidation of the methionine residue produces a sulfoxide that elutes close to the parent peak in many chromatographic systems. Hydrolysis of peptide bonds and deamidation of susceptible residues in related sequences also reduce purity over time. Lyophilised material kept dry at minus twenty degrees Celsius and shielded from light is the most stable form commonly described in laboratory practice.
=== Comparison to similar agents === The clinical effectiveness of methocarbamol compared to other muscle relaxants is not well known. One trial of methocarbamol versus cyclobenzaprine, a well-studied muscle relaxant, in those with localized muscle spasm found there were no significant differences in their effects on muscle spasm, limitation of motion, or limitation of daily activities.
== Pharmacology == Like ibogaine, it has seems to have similar pharmacology. It has effects on KOR, NMDAR, nAChR and serotonin sites. It also inhibits acetylcholinesterase and butyrylcholinesterase. Ibogamine persistently reduced the self-administration of cocaine and morphine in rats. The same study found that ibogamine (40 mg/kg) and coronaridine (40 mg/kg) did not produce "any tremor effects in rats that differ significantly from saline control". While the related alkaloids ibogaine (20–40 mg/kg), harmaline (10–40 mg/kg) and desethylcoronaridine (10–40 mg/kg) were "obviously tremorgenic".
nicotinate D-ribonucleotide + diphosphate + ADP + phosphate Thus, the four substrates of this enzyme are nicotinate, 5-phospho-alpha-D-ribose 1-diphosphate, ATP, and H2O, whereas its four products are nicotinate D-ribonucleotide, diphosphate, ADP, and phosphate. This enzyme belongs to the family of ligases, specifically those forming generic carbon-nitrogen bonds. The systematic name of this enzyme class is 5-phospho-alpha-D-ribose 1-diphosphate:nicotinate ligase (ADP, diphosphate-forming) .
Arthritis – Types – Fibromyalgia by the CDC Fibromyalgia by the National Institute of Arthritis and Musculoskeletal and Skin Diseases Fibromyalgia by the American College of Rheumatology Fibromyalgia by the NHS
Viscosity is measured with various types of viscometers and rheometers. Close temperature control of the fluid is essential to obtain accurate measurements, particularly in materials like lubricants, whose viscosity can double with a change of only 5 °C. A rheometer is used for fluids that cannot be defined by a single value of viscosity and therefore require more parameters to be set and measured than is the case for a viscometer. For some fluids, the viscosity is constant over a wide range of shear rates (Newtonian fluids). The fluids without a constant viscosity (non-Newtonian fluids) cannot be described by a single number. Non-Newtonian fluids exhibit a variety of different correlations between shear stress and shear rate. One of the most common instruments for measuring kinematic viscosity is the glass capillary viscometer. In coating industries, viscosity may be measured with a cup in which the efflux time is measured. There are several sorts of cup—such as the Zahn cup and the Ford viscosity cup—with the usage of each type varying mainly according to the industry. Also used in coatings, a Stormer viscometer employs load-based rotation to determine viscosity. The viscosity is reported in Krebs units (KU), which are unique to Stormer viscometers. Vibrating viscometers can also be used to measure viscosity. Resonant, or vibrational viscometers work by creating shear waves within the liquid. In this method, the sensor is submerged in the fluid and is made to resonate at a specific frequency.
Sources: en.wikipedia.org
== Description == The species grows to be about 50 mm, or about 2 inches. This slug has been treated as a model organism and used in studies into classical conditioning, memory consolidation and associative learning, the structure of neural circuits and neural physiology. It has also been used to investigate ultrastructure and anatomy, larval and reproductive ecology, behavioral ecology and pharmacology and toxicology including studies into Beta thymosins. Unfortunately these studies did not differentiate between the three species of Hermissenda.
=== Christmas Island and the B.P.C. === Following the Nauru Agreement of 2 July 1919 the interests of the PPC in the phosphate deposits in Nauru and Ocean Island were acquired by the governments of the United Kingdom, Australia and New Zealand, which carried out mining under the direction of the Board of Commissioners, which represented the three governments.
== Adverse effects and contraindications == Like other antiarrhythmics, ibutilide can lead to abnormal heart rhythms due to its ability to prolong the QT interval, which can lead to the potentially fatal abnormal heart rhythm known as torsades de pointes. Consequently, the drug is contraindicated in patients that are likely to develop abnormal heart rhythms; this includes individuals who have previously experienced polymorphic ventricular tachycardia, have a prolonged QT interval, sick sinus syndrome, or have recently had a myocardial infarction, among other conditions.
== Personal life == Princess Esra married Prince Mukarram Jah in 1959. They were married for 15 years. They have a son Azmet (born 1962) and a daughter Shekhya (born 1964). She lives in London. Princess Esra hospital was established by her in the year 1972 to provide subsidized medical facilities for the people of old city Hyderabad. This hospital was recently acquired on lease by Owaisi group of hospitals.
Sources: en.wikipedia.org
==== Imaging ==== Ultrasound of the thyroid may be used to reveal whether structures are solid or filled with fluid, helping to differentiate between nodules and goitres and cysts. It may also help differentiate between malignant and benign lesions. When further imaging is required, a radiolabelled iodine-123 or technetium-99 uptake scan may take place. This can determine the size and shape of lesions, reveal whether nodules or goitres are metabolically active, and reveal and monitor sites of thyroid disease or cancer deposits outside the thyroid. A fine needle aspiration of a sample of thyroid tissue may be taken in order to evaluate a lesion seen on ultrasound which is then sent for histopathology and cytology. Computed tomography of the thyroid plays an important role in the evaluation of thyroid cancer. CT scans often incidentally find thyroid abnormalities, and thereby practically becomes the first investigation modality.
=== Pervasive expression === With the development of technologies such as RNA-seq and Ribo-seq, eukaryotic genomes are now known to be pervasively transcribed and translated. Many ORFs that are either unannotated, or annotated as long non-coding RNAs (lncRNAs), are translated at some level, either in a condition or tissue-specific manner. Though infrequent, these translation events expose non-genic sequence to selection. This pervasive expression forms the basis for several models describing de novo gene birth. It has been speculated that the epigenetic landscape of de novo genes in the early stages of formation may be particularly variable between and among populations, resulting in variable gene expression thereby allowing young genes to explore the "expression landscape." The QQS gene in A. thaliana is one example of this phenomenon; its expression is negatively regulated by DNA methylation that, while heritable for several generations, varies widely in its levels both among natural accessions and within wild populations. Epigenetics are also largely responsible for the permissive transcriptional environment in the testes, particularly through the incorporation into nucleosomes of non-canonical histone variants that are replaced by histone-like protamines during spermatogenesis.
== Clinical significance == There is a rare pathology known as edema of Wharton’s jelly. Its causes have not been established. In some cases, the development of edema is associated with fetal hydrops. In addition, edema may occur in cases of umbilical cord hemangiomas. In such cases, the risk of compression of the umbilical cord vessels increases, which may lead to impaired blood supply to the fetus. Wharton’s jelly edema is usually detected in the second half of pregnancy. The edema may involve the entire umbilical cord or only certain segments of it. In addition to edema, pathologies of Wharton’s jelly include mucoid degeneration accompanied by the formation of pseudocysts, as well as underdevelopment and constriction (coarctation) of the umbilical cord. A 2015 study showed that transplantation of Wharton’s jelly tissue may be considered as a strategy for the treatment of traumatic brain injury.
== Education == Brigitte Askonas was born to Czechoslovak parents, Jewish converts to Catholicism, who fled Austria after the Nazi takeover. Vienna-born Askonas studied biochemistry at McGill University (BSc, MSc) and carried out her postgraduate work in the school of biochemistry at the University of Cambridge where she was a student of Girton College, Cambridge and worked in Frederick Sanger's laboratory from 1948 to 1952. Her role models in the department included two distinguished scientists, Marjory Stephenson and Dorothy Needham, two of the first women to be elected to the Royal Society. She said they taught her that "good science gets recognition regardless of the sex of the scientist". Her PhD research was supervised by Malcolm Dixon.
PET scanning with the radiotracer [18F]fluorodeoxyglucose (FDG) is widely used in clinical oncology. FDG is a glucose analog that is taken up by glucose-using cells and phosphorylated by hexokinase (whose mitochondrial form is significantly elevated in cancer). Metabolic trapping of the radioactive glucose molecule allows the PET scan to be utilized. The concentrations of imaged FDG tracer indicate tissue metabolic activity as it corresponds to the regional glucose uptake. FDG is used to explore the possibility of cancer spreading to other body sites (cancer metastasis). These FDG PET scans for detecting cancer metastasis are the most common in standard medical care (representing 90% of current scans). The same tracer may also be used for the diagnosis of types of dementia. Less often, other radioactive tracers, usually but not always labelled with fluorine-18 (18F), are used to image the tissue concentration of different kinds of molecules of interest inside the body. Because the hydroxy group that is replaced by fluorine-18 to generate FDG is required for the next step in glucose metabolism in all cells, no further reactions occur in FDG. Furthermore, most tissues (with the notable exception of liver and kidneys) cannot remove the phosphate added by hexokinase. This means that FDG will remain trapped in any cell that takes it up until it decays, since phosphorylated sugars, due to their ionic charge, cannot exit from the cell.
Sources: en.wikipedia.org
Semax is based on the ACTH(4-10) fragment, a seven-amino-acid segment of adrenocorticotropic hormone. The synthetic peptide retains the core sequence while removing regions associated with endocrine activity. This modification is intended to isolate effects on the nervous system.
It is registered for clinical use in Russia and a few other countries, typically as a nasal drop formulation. It does not hold approval from the United States Food and Drug Administration or the European Medicines Agency. Outside those markets it is generally handled as a research chemical.
The compound was developed in Moscow and the earliest studies were conducted there, so the primary literature is largely in Russian-language journals. Translation and indexing have been incomplete, which limits access for outside researchers. Independent groups have since published some work, but the total volume remains modest.
电喷雾或基质辅助激光解吸电离质谱是常用手段，测得的质子化离子质荷比可换算为分子量。结果与理论值落在合理误差内，才支持结构一致的判断。