Everything below concerns mass spectrometry. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2025-10-17. Numbers and descriptions here follow the published literature rather than marketing material.
Published research covers ischemic stroke, traumatic brain injury, cognitive impairment, optic nerve conditions and attention-related measures. Much of the human evidence comes from small trials conducted in one country, which limits how far the results generalize. Animal models supply the larger share of the data, and effects seen in rodents do not transfer automatically to people. Reviews have noted that methodological reporting is often incomplete, making it difficult to pool results or compare treatment schedules across studies.
Pharmacokinetic accounts emphasize rapid breakdown. After intravenous dosing the intact peptide disappears from blood within minutes, and nasal delivery produces low but measurable concentrations. Metabolites rather than the parent molecule may account for part of the observed activity, although the relative contribution is unresolved. Dosing in the literature varies widely and no optimal schedule has been agreed. These gaps are regularly cited as a reason the findings have not produced broad clinical adoption beyond the original research setting.
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.
| Property | Value | Notes |
|---|---|---|
| Primary research models | Rodent studies | Largest share of published data |
| Reported markers | BDNF and NGF expression | Measured mainly in animal tissue |
| Common administration | Intranasal | Matches the registered formulation |
| Blood residence time | Minutes | Rapid enzymatic degradation |
| Evidence quality | Small trials, limited replication | Noted repeatedly in reviews |
Identity and purity are established with standard peptide methods. Reversed-phase HPLC with ultraviolet detection near 214 nm resolves the parent peak from deletion and truncation byproducts, and reports typically quote a main-peak percentage. Mass spectrometry by electrospray or MALDI-TOF confirms the expected molecular mass, while amino acid analysis or peptide mapping can verify composition when the sequence itself is in question. A certificate of analysis that pairs a chromatogram with a mass spectrum is more informative than a purity figure alone. Counter-ion content and residual solvents are separate specifications and are frequently omitted.
Semax is normally supplied as a lyophilized powder, and that form is the most stable. Suppliers commonly recommend storage at -20 °C in a desiccated container protected from light, with short-term handling at room temperature limited to weighing and transfer. Powder that has absorbed moisture degrades faster, so vials should be warmed to ambient temperature before opening to prevent condensation on the contents. Hygroscopic behavior is typical of short hydrophilic peptides, and humidity control matters more than temperature alone for long-term retention.
Regulatory status differs sharply between jurisdictions. In Russia the peptide is registered as a prescription nasal preparation, while agencies such as the United States Food and Drug Administration have not approved it for any indication. Products sold elsewhere are typically labeled for laboratory research only, and such labels shift responsibility for safe handling to the purchaser. Because the same name covers pharmaceutical-grade nasal drops and bulk research powder, identity and purity documentation becomes the main practical concern when comparing sources.
Semax is a synthetic seven-amino-acid peptide whose sequence extends the ACTH(4-10) fragment with a C-terminal proline-glycine-proline tripeptide. The commonly cited sequence is Met-Glu-His-Phe-Pro-Gly-Pro, giving a molecular formula near C37H51N9O10S and a molecular weight close to 813.9 g/mol. It belongs to the broader class of synthetic ACTH fragments studied for central nervous system effects rather than for adrenal steroid stimulation. In practice the material appears as a lyophilized white powder for laboratory work or as a dilute saline solution in clinical settings.
Development is attributed to researchers at the Institute of Molecular Genetics in Moscow during the early 1980s, building on earlier Soviet work with ACTH fragments. Russian regulatory approval followed for intranasal use, and the compound has remained commercially available there for decades. Most published human data originate from Russian and, later, some Eastern European clinical reports, which are not always accessible in English translation. Outside that region the material is generally handled as a research chemical rather than a licensed medicine.
常规纯度与身份确认依赖反相高效液相色谱，并辅以质谱测定分子量。氨基酸组成分析可用于验证序列构成，肽图分析则能进一步定位修饰或降解产物。杂质谱通常关注缺失序列肽、截短片段和氧化产物。不同方法的检出限并不相同，因此各实验室报告的纯度数值不宜直接横向比较。
多数实验室与市售的 Semax 以冻干粉形式提供。冻干粉通常建议保存在 -20 °C 或更低温度下，同时避免光照与反复升温。短期运输有时采用冷藏条件，但长期保存仍以冷冻为主。分包操作应尽量减少开盖次数，以降低吸湿和微生物污染的风险。开封后若未一次用完，建议在干燥环境中密封并尽快放回低温储存。
溶液状态的稳定性明显低于冻干粉。肽类在水溶液中可能经历水解、氧化与聚集，其中甲硫氨酸和天冬酰胺等残基常是敏感位点。Semax 含有甲硫氨酸，因此氧化风险相对突出。工作液一般主张现配现用，或冷藏并在数日内用尽。缓冲液种类、pH 和离子强度都会影响降解速率，而关于最佳条件的公开数据并不统一。
A group of individuals who share a common trait, such as birth year. In medicine, a cohort is a group that is part of a clinical trial or study and is observed over a period of time. (NCI) In epidemiology, a group of individuals with some characteristics in common. (NLM) Cohort study
Indirect discrimination is often structural, and this is seen in the gender pay gap of 21.7% across the Australian workforce, meaning women employees earn on average 78.3 cents compared to each $1 for male employees, according to the annual employer census. The main reasons for the gender pay gap are sex discrimination in child care and parental leave laws based on "persistent cultural norms that see women as more likely to undertake primary carer duties for children and family", "outright gender-based discrimination at work", "patterns of workforce engagement" and occupational segregation. Under the Fair Work Act 2009 section 302, employees, unions and the Sex Discrimination Commissioner can make an equal pay claim. The first post-2009 cases were brought by unions for social and community service workers, supported by the government. The Fair Work Commission interprets the appropriate comparator narrowly. Before 2009, the Librarians case, librarians were awarded a pay increase since the skill and education levels were comparable to better paid male-dominated industries. Structural discrimination also underlies much of the race pay gap in Australia. The first time Indigenous employees became legally entitled to equal pay with white workers, in cattle and farming jobs, was through a decision in 1966. The exclusion in the Conciliation and Arbitration Act 1904 section 4 for "persons engaged in domestic service" meant that many Indigenous women and girls employed as domestic staff were excluded.
In contrast nitrooxylation of 1 with nitric acid gives the apical nitrate 4 as an intermediate which is hydrolysed to the apical alcohol 5 due to the higher steric demand of the active electrophilic NO−2HNO+3 species. This alcohol can react with thionyl bromide to the bromide 6 and in a series of steps (not shown) to the corresponding thiol. Pentamantane can also react with tetrabromomethane and tetra-n-butylammonium bromide (TBABr) in a free radical reaction to the bromide but without selectivity.
Chargaff's rules A set of axioms which state that, in the DNA of any chromosome, species, or organism, the total number of adenine (A) residues will be approximately equal to the total number of thymine (T) residues, and the number of guanine (G) residues will be equal to the number of cytosine (C) residues; accordingly, the total number of purines (A + G) will equal the total number of pyrimidines (T + C). These observations illustrate the highly specific nature of the complementary base-pairing that occurs in all duplex DNA molecules: even though non-standard pairings are technically possible, they are exceptionally rare because the standard ones are strongly favored in most conditions. Still, the 1:1 equivalence is seldom exact, since at any given time nucleobase ratios are inevitably distorted to some small degree by unrepaired mismatches, missing bases, and non-canonical bases. The presence of single-stranded DNA polymers also alters the proportions, as an individual strand may contain any number of any of the bases.
According to Kristen Ghodsee, the triumphalist attitudes of Western powers at the end of the Cold War and the fixation with linking all leftist and socialist ideals with the excesses of Stalinism allowed neoliberalism to fill the void. This undermined democratic institutions and reforms, leaving a trail of economic misery, unemployment, hopelessness and rising economic inequality throughout the former Eastern Bloc and much of the West in the following decades. With democracy weakened and the anti-capitalist left marginalised, the anger and resentment which followed the period of neoliberalism was channeled into extremist nationalist movements in both the former and the latter.
Sources: en.wikipedia.org
== Etymology == Medicine (UK: , US: ) is the science and practice of the diagnosis, prognosis, treatment, and prevention of disease. The word "medicine" is derived from Latin medicus, meaning "a physician". The word "physic" itself, from which "physician" derives, was the old word for what is now called a medicine, and also the field of medicine.
Tametraline, a compound synthesized in 1978 by Pfizer, was shown to be a potent NE and DA re-uptake inhibitor with animal studies. Later on a surprisingly substantial enhancement of blocking activity of 5-HT uptake was achieved by adding chlorine atoms at C-3 and C-4 to the structure of tametraline, resulting in (+)-trans-(1R,4S)-N-methyl-4-phenyl-1-aminotetralin, a potent but nonselective uptake blocker. The (+)-cis-(1S,4S)-isomer, one of four compounds diastereomers, however exhibited significantly more selective and potent 5-HT uptake inhibiting activity compared to the other three diastereomers, where the 4-phenyl ring favours attachments at 5-HT uptake sites. The compound was named sertraline (figure 8). Although sertraline appears to differ structurally from the other SSRIs, it has a phenylaminotetralin in its structure, in which the diphenylpropylamine nucleus has been forced into a stiff bicyclic ring system. Sertraline is the second most potent inhibitor of 5-HT re-uptake which has two very interesting characteristics that distinguish it i.e. sertraline's (1) inhibiting effect on DAT and NET and (2) the binding to sigma-1 (σ1) receptor in CNS. The DAT and NET inhibition is controversial because of much weaker inhibition which it has, compared to SERT inhibition. Sertraline has about 60 times more potent inhibition potential on 5-HT than either NE or DA re-uptake. It is possible that only modest inhibition of DAT and NET is needed to cause an increase in energy, motivation and concentration, specially when added to other activity such as SERT inhibition.
== Research directions == Outside of H. pylori eradication and ulcer management, the broader antimicrobial potential and gastric‑protective roles of bismuth subcitrate are not well studied in clinical trials; this is a potential research direction. Bismuth is also studied on potential antiviral and antileishmanial applications.
All Danish citizens above 18 years of age can apply for some financial support if they cannot support themselves or their family. Approval is not automatic, and the extent of this system has generally been diminished since the 1980s. Sick people can receive some financial support throughout the extent of their illness. Their ability to work will be re-evaluated by the municipality after 5 months of illness. The welfare system related to the labor market has experienced several reforms and financial cuts since the late 1990s due to political agendas for increasing the labor supply. Several reforms of the rights of the unemployed have followed up, partially inspired by the Danish Economic Council. Halving the time unemployment benefits can be received from four to two years, and making it twice as hard to regain this right, was implemented in 2010 for example. Disabled people can apply for permanent social pensions. The extent of the support depends on the ability to work, and people below 40 are not eligible unless deemed incapable of any kind of work.
Countercurrent chromatography (CCC, also counter-current chromatography) is a form of liquid–liquid chromatography that uses a liquid stationary phase that is held in place by inertia of the molecules composing the stationary phase accelerating toward the center of a centrifuge due to centripetal force and is used to separate, identify, and quantify the chemical components of a mixture. In its broadest sense, countercurrent chromatography encompasses a collection of related liquid chromatography techniques that employ two immiscible liquid phases without a solid support. The two liquid phases come in contact with each other as at least one phase is pumped through a column, a hollow tube or a series of chambers connected with channels, which contains both phases. The resulting dynamic mixing and settling action allows the components to be separated by their respective solubilities in the two phases. A wide variety of two-phase solvent systems consisting of at least two immiscible liquids may be employed to provide the proper selectivity for the desired separation. Some types of countercurrent chromatography, such as dual flow CCC, feature a true countercurrent process where the two immiscible phases flow past each other and exit at opposite ends of the column. More often, however, one liquid acts as the stationary phase and is retained in the column while the mobile phase is pumped through it.
Sources: en.wikipedia.org
Asparagine endopeptidase (AEP, mammalian legumain, δ-secretase; EC 3.4.22.34) is a proteolytic enzyme from C13 peptidase family which hydrolyses a peptide bond using the thiol group of a cysteine residue as a nucleophile (hence also called cysteine protease). It is also known as asparaginyl endopeptidase, citvac, proteinase B, hemoglobinase, PRSC1 gene product or LGMN (Homo sapiens), vicilin peptidohydrolase and bean endopeptidase. In humans it is encoded by the LGMN gene (previous symbol PRSC1). It hydrolyzes substrates at the C-terminus of asparagine residues. Discovered in 1996 in beans, its homologues have been identified in plants, protozoa, vertebrates, and helminths. The enzyme has been implicated in several human diseases such as cancer, atherosclerosis and inflammation . It can be detected in spleen, liver, brain, testis tissue and heart and the protein is mostly localised to lysosomes and endosomes. It is also interesting that AEP is activated in age-dependent manner.
=== Approved drugs === Emoxypine (ethylmethylhydroxypyridine; Mexidol) – antioxidant and unknown mechanism of action [135] Tandospirone (metanopirone; Sediel; SM-3997) – serotonin 5-HT1A receptor partial agonist [136] Tianeptine (Coaxil; Stablon; Tatinol) – weak atypical μ-opioid receptor agonist and other actions [137]
A minor figure in the British Union of Fascists (BUF) at the time, Hamm moved to the Falkland Islands in 1939 to work as a teacher. He was arrested there (under Defence Regulation 18B) in 1940 for encouraging fascist views among his pupils and his BUF membership and later transferred to a prison camp in South Africa.
There were almost 18.3 million connections to the Internet in June 2014. According to Bloomberg, in 2013 Romania ranked fifth in the world, and according to The Independent, it ranks number one in Europe at Internet speeds, with Timișoara ranked among the highest in the world.
There is experimental and clinical evidence that, at least in optic neuritis speed of treatment initiation is important. Vulnerability to infection: By suppressing immune reactions (which is one of the main reasons for their use in allergies), steroids may cause infections to flare up, notably candidiasis. Pregnancy: Corticosteroids have a low but significant teratogenic effect, causing a few birth defects per 1,000 pregnant women treated. Corticosteroids are therefore contraindicated in pregnancy. Habituation: Topical steroid addiction (TSA) or red burning skin has been reported in long-term users of topical steroids (users who applied topical steroids to their skin over a period of weeks, months, or years). TSA is characterised by uncontrollable, spreading dermatitis and worsening skin inflammation which requires a stronger topical steroid to get the same result as the first prescription. When topical steroid medication is lost, the skin experiences redness, burning, itching, hot skin, swelling, and/or oozing for a length of time. This is also called 'red skin syndrome' or 'topical steroid withdrawal' (TSW). After the withdrawal period is over the atopic dermatitis can cease or is less severe than it was before. In children the short term use of steroids by mouth increases the risk of vomiting, behavioral changes, and sleeping problems. Dysphonia: Inhaled corticosteroids are used for treatment of asthma as a standard treatment. This can cause local adverse effects like vocal cord dysfunction.
Sources: en.wikipedia.org
The main proposal is modulation of neurotrophic factors such as brain-derived neurotrophic factor, supported largely by animal experiments. Receptor-level targets have not been firmly established. Most reviews describe the mechanism as only partially characterized.
The compound is registered as a medicine in Russia, so clinical work has concentrated there. Trials elsewhere are few and generally small. This geographic concentration is a recognized limitation in evidence reviews.
Some fraction may reach the central nervous system through olfactory pathways, and this is often cited as the rationale for the nasal route. The size of that fraction in humans is not well quantified. Blood concentrations after nasal dosing are low, which complicates measurement.
Semax is a synthetic seven-amino-acid peptide derived from a fragment of corticotropin. It is used in Russia as a nasal preparation, while elsewhere it is studied as a research compound. It is not approved as a medicine in most countries.