The short version of neurotrophic signaling fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-07-06. Anything still debated is marked as such rather than presented as settled.
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.
Proposed mechanisms center on neurotrophic signaling rather than on classical melanocortin receptor activation. Rodent experiments have reported shifts in the expression of brain-derived neurotrophic factor and nerve growth factor after administration, together with changes in the associated receptor systems. Several authors argue that the peptide acts largely through its degradation products and their interaction with peptidergic pathways, but this remains a hypothesis rather than a settled finding. No single molecular target has been identified in a way that the field broadly accepts.
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.
Terminology around the compound varies by source. It appears in catalogues and papers as Semax, as the heptapeptide ACTH(4-7)-Pro-Gly-Pro, and under various alphanumeric laboratory codes used by individual suppliers. These names refer to the same sequence but may imply different salt forms, purity grades, or counter-ions. Peptide databases usually list the free base mass, while product descriptions sometimes report acetate or trifluoroacetate salts with a different formula weight. Because naming conventions for research peptides are not standardised across vendors, checking the declared sequence and measured mass is more reliable than relying on a trade name alone.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Its design combines the ACTH(4-7) core fragment with a C-terminal Pro-Gly-Pro extension, a modification intended to improve stability and prolong activity. The molecule is hydrophilic, carries no lipid chains or glycosylation, and has a theoretical mass just over 810 daltons in its free form. All seven residues are proteinogenic amino acids, so no non-natural building blocks appear in the backbone. A free N-terminal methionine and C-terminal proline define the unmodified parent peptide.
The compound was developed during the 1980s at the Institute of Molecular Genetics in Moscow as part of research on fragments of adrenocorticotropic hormone. Early work examined short ACTH-derived sequences that retained neurotrophic effects while lacking the endocrine activity of the full hormone. Semax entered clinical use in Russia during the 1990s, where it received registration for several neurological indications. Outside that region it remained primarily a laboratory research material rather than an approved therapeutic. English-language literature on it grew more slowly and frequently cited the original Russian studies.
| 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 |
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.
Reported pharmacological work centers on neurotrophic signaling, including changes in BDNF and NGF expression in hippocampal tissue in animal models. Human data come largely from studies conducted in Russia, and how well those results generalize to other populations remains an open question. Regulatory status differs sharply by jurisdiction: Semax is a registered prescription medicine in Russia, while it holds no approved marketing status in the United States or the European Union. Outside such jurisdictions it is generally handled as a research chemical, which affects both documentation and quality expectations.
Semax is a synthetic heptapeptide whose sequence is Met-Glu-His-Phe-Pro-Gly-Pro. It was developed as a fragment analog of adrenocorticotropic hormone, modeled specifically on the ACTH(4-10) region. The first four residues reproduce that fragment, while a Pro-Gly-Pro tripeptide is appended at the C-terminus. Work on the compound originated in Russia, where it entered clinical use as an intranasal preparation. Its sequence places it among short regulatory peptides studied for effects on the central nervous system rather than on the adrenal axis.
The C-terminal Pro-Gly-Pro extension is not incidental. Proline-rich tails are known to resist several common peptidases, and the published literature attributes the longer half-life of Semax, relative to unmodified ACTH fragments, to this feature. The modification also removes the melanocyte-stimulating and corticosteroidogenic activity that characterizes longer ACTH-derived sequences. Because the molecule is small and hydrophilic, it is typically formulated as an aqueous solution for intranasal or parenteral delivery. Acetylation or amidation at the termini appears in closely related research peptides and shifts the mass by a fixed increment.
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。
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.
Janaki Ramachandran of the AIADMK became the first woman to hold the position of the state's chief minister. J. Jayalalithaa of the AIADMK became the youngest Chief Minister of Tamil Nadu at the age of 43 in 1991, and had the second longest tenure, holding the office for more than fourteen years across multiple terms. There have been four instances of President's rule in Tamil Nadu, most recently in 1991. C. Joseph Vijay of the Tamilaga Vettri Kazhagam is the incumbent Chief Minister since 10 May 2026.
Borodinsky bread is a slightly sweet sourdough rye bread of Russian origin, usually flavoured by caraway and coriander seeds and sweetened with molasses, which augments its already quite dark colour coming from the rye flour. It is named after the Battle of Borodino, and the legend says that it was invented by the widow of one of the Russian generals who died in that battle, though in reality it was probably created much later, at the end of the 19th century.
A Ramachandran plot (also known as a Ramachandran diagram or a [φ,ψ] plot), originally developed in 1963 by G. N. Ramachandran, C. Ramakrishnan, and V. Sasisekharan, is a way to visualize energetically allowed regions for backbone dihedral angles ψ against φ of amino acid residues in protein structure. In a protein chain three dihedral angles are defined:
Mauritania was the last country to abolish slavery (in 1981), and it is estimated that 20% of its population of 3 million people are enslaved as bonded labourers, with black Haratin being slaves and Berbers and Arabs the owners. Slavery in Mauritania was criminalized in August 2007. However, although slavery, as a practice, was legally banned in 1981, it was not a crime to own a slave until 2007. Although many slaves have escaped or have been freed since 2007, as of 2012, only one slave owner had been sentenced to serve time in prison.
== Climate == Climate Change Performance Index (CCPI) 2020: Of 57 nations responsible for about 90% of global energy-related CO2 emissions, Thailand was ranked 33rd, "poor". Other ASEAN nations ranked were Indonesia, 39 "poor" and Malaysia, 53 "very poor". Among other findings, Thailand's population and greenhouse gas (GHG) emissions continue to rise and its climate policy is "poor". Germanwatch's Global Climate Risk Index 2019 analyzes the extent to which countries have been affected by climate risks—impacts of weather-related loss events (storms, floods, heat waves, etc.). The most recent data available, for 2017 and from 1998 to 2017, are the basis of the report, which uses an algorithm based on deaths and financial losses. For the period 1998–2017, Thailand ranked 13 of 181 nations (1=most affected; 181=least affected). Other ASEAN nations were ranked: Myanmar, 3; Philippines, 5; Vietnam, 9; Cambodia, 19; Indonesia, 69; Laos, 89; Malaysia, 116; Brunei, 175; Singapore, 180. In 2019, YouGov surveyed 30,000 citizens in 28 nations about their views on climate change and the role of humans, if any, in causing it. Sixty-nine percent of Thais thought that the climate is changing and that humans were mostly responsible for it. Most of the people of other ASEAN nations surveyed were largely in agreement: Indonesia, 69%; Vietnam, 64%; Philippines, 62%; Singapore, 54%; and Malaysia, 48%. Global Climate Risk Index 2018: Thailand was ranked ninth on a list of countries most affected by extreme weather events during the period 1997–2016.
Sources: en.wikipedia.org
== History == Flucloxacillin was developed in the 1960s, following an increase in penicillin-resistant (beta-lactamase producing) staphylococcal infections, due to the widespread use of benzylpenicillin by 1960. All the natural penicillins and first semi-synthetic penicillins were destroyed by staphylococcal beta-lactamase, leading Beecham (later GlaxoSmithKline) to search for more stable antibiotics. By 1962, a series of similarly structured acid-stable penicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin), with the potential for being taken by mouth, were developed. Flucloxacillin and dicloxacillin showed particular stability against the beta-lactamase enzyme of Staph. aureus and could withstand acid. Beecham further developed cloxacillin and popularised flucloxacillin in the UK, while Bristol Laboratories concentrated on marketing oxacillin and dicloxacillin in the United States, leading to the difference in use in each country. Flucloxacillin was first marketed in Europe in the 1970s.
== N == NEMS-MS – Nanoelectromechanical systems mass spectrometry NETD – Negative electron-transfer dissociation NICI – Negative ion chemical ionization NRMS – Neutralization reionization mass spectrometry
=== Pharmacodynamics === Nemonapride has been described both as a typical antipsychotic and as an atypical antipsychotic. It is a potent and selective dopamine D2, D3, and D4 receptor antagonist. Its affinities (Ki) for these receptors are 0.16 nM for the dopamine D2 receptor, 0.26 nM for the dopamine D3 receptor, and 0.31 nM for the dopamine D4 receptor. Antagonism of the dopamine D2 receptor is thought to be responsible for the antipsychotic effects of nemonapride. In addition to the dopamine D2-like receptors, nemonapride has weaker affinity for the serotonin 5-HT1A and 5-HT2A receptors. Its affinities (Ki) for these receptors are 1.8 nM for the serotonin 5-HT1A receptor (11-fold lower than for the D2 receptor) and 9.4 nM for the serotonin 5-HT2A receptor (59-fold lower than for the D2 receptor). It is a partial agonist of the serotonin 5-HT1A receptor. It has very weak affinity for sigma receptors (Ki = 80–3,000 nM) as well. Besides these specific receptors, nemonapride is described as having very weak affinity for the dopamine D1, serotonin 5-HT2, adrenergic, and cholinergic receptors. In animals, nemonapride suppresses conditioned avoidance responses, inhibits methamphetamine- and apomorphine-induced hyperactivity and stereotypy, produces catalepsy, and has slight central depressant effects.
Brine pockets which are accessed by smaller pores can experience a higher abundance of photoautotrophic protists as well as smaller heterotrophic protists due to limited grazing pressure by the reduced abundance of large predators, such as large ciliates and metazoan predators.
Cross-flowing is a passive formation method that involves the continuous and aqueous phases running at an angle to each other. Most commonly, the channels are perpendicular in a T-shaped junction with the dispersed phase intersecting the continuous phase; other configurations such as a Y-junction are also possible. The dispersed phase extends into the continuous and is stretched until shear forces break off a droplet. In a T-junction, droplet size and formation rate are determined by the flow rate ratio and capillary number. The capillary number relates the viscosity of the continuous phase, the superficial velocity of the continuous phase, and the interfacial tension. Typically, the dispersed phase flow rate is slower than the continuous flow rate. T-junction formation can be further applied by adding additional channels, creating two T-junctions at one location. By adding channels, different dispersed phases can be added at the same point to create alternating droplets of different compositions. Droplet size, usually above 10 μm, is limited by the channel dimensions and often produces droplets with a CV of less than 2% with a rate of up to 7 kHz.
Sources: en.wikipedia.org
=== Common shape codes === General Service/General Lighting Service (GLS) Light emitted in (nearly) all directions. Available either clear or frosted. Types: General (A), elliptical (E), mushroom (M), sign (S), tubular (T) 120 V sizes: A17, 19 and 21 230 V sizes: A55 and 60 High Wattage General Service Lamps greater than 200 watts. Types: Pear-shaped (PS) Decorative lamps used in chandeliers, etc. Smaller candle-sized bulbs may use a smaller socket. Types: candle (B), twisted candle, bent-tip candle (CA & BA), flame (F), globe (G), lantern chimney (H), fancy round (P) 230 V sizes: P45, G95 Reflector (R) Reflective coating inside the bulb directs light forward. Flood types (FL) spread light. Spot types (SP) concentrate the light. Reflector (R) bulbs put approximately double the amount of light (foot-candles) on the front central area as General Service (A) of same wattage. Types: Standard reflector (R), bulged reflector (BR), elliptical reflector (ER), crown-silvered 120 V sizes: R16, 20, 25 and 30 230 V sizes: R50, 63, 80 and 95 Parabolic aluminized reflector (PAR) Parabolic aluminized reflector (PAR) bulbs control light more precisely. They produce about four times the concentrated light intensity of general service (A), and are used in recessed and track lighting. Weatherproof casings are available for outdoor spot and flood fixtures. 120 V sizes: PAR 16, 20, 30, 38, 56 and 64 230 V sizes: PAR 16, 20, 30, 38, 56 and 64 Available in numerous spot and flood beam spreads. Like all light bulbs, the number represents the diameter of the bulb in 1⁄8 of an inch.
Semiconductors, metals, and ceramics are used today to form highly complex systems, such as integrated electronic circuits, optoelectronic devices, and magnetic and optical mass storage media. Semiconductors are a traditional example of these types of materials. They are materials that have properties that are intermediate between conductors and insulators. Their electrical conductivities are very sensitive to the concentration of impurities, which allows the use of doping to achieve desirable electronic properties. Hence, semiconductors form the basis of the traditional computer. This field also includes new areas of research such as superconducting materials, spintronics, metamaterials, etc. The study of these materials involves knowledge of materials science and solid-state physics or condensed matter physics.
=== Research and contributions === Laposata is the author of Laposata's Laboratory Medicine: Diagnosis of Disease in the Clinical Laboratory (McGraw Hill), now in its fourth edition.[2] He has published more than 200 peer-reviewed papers focusing on fatty acid metabolism and diagnostic studies in coagulation.[2] As an expert in bleeding and clotting disorders that can mimic child abuse, his testimony has been reported to have contributed to exonerations and to children being returned to their families.[3]
== Traditional use == Skullcaps are used in traditional medicine, such as in traditional Chinese medicine. The root of Scutellaria baicalensis – a common component of many preparations – is marketed in volumes that have led to the overexploitation of the wild plant. Its rarity has led to an increase in price, and encouraged the adulteration of the product with other species of Scutellaria. In 1773, Scutellaria lateriflora became a common treatment in North America for the hysteria and hydrophobia caused by rabies. Today it is still a popular medicinal herb. It is widely available as a commercial product used in western herbalism. The plant reportedly commands prices of $16 to $64 per pound dry weight.
== Uses == Cold chains are common in the food and pharmaceutical industries and also in some chemical shipments. One common temperature range for a cold chain in pharmaceutical industries is 2 to 8 °C (36 to 46 °F), but the specific temperature (and time at temperature) tolerances depend on the actual product being shipped.
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.
It is a synthetic seven-amino-acid peptide built from the ACTH(4-7) sequence plus a Pro-Gly-Pro tail. It belongs to the family of short ACTH fragments studied for nervous-system effects. Its backbone contains only standard amino acids.