This is a working overview of heptapeptide, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2025-09-16 and is reviewed periodically as new material appears.
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.
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.
Semax binds to melanocortin receptors and is thought to influence neuronal survival and plasticity rather than to act through the adrenal axis. Laboratory work has shown increased expression of brain-derived neurotrophic factor and nerve growth factor in treated tissue. Changes in c-Fos, a marker of neuronal activation, have also been reported. Because the peptide is rapidly degraded by peptidases, its effects are generally attributed to downstream signaling cascades rather than to sustained receptor occupancy.
Published studies are dominated by animal models of stroke, ischemia, and cognitive impairment, with a smaller number of human trials conducted in Russia. Many of the human reports are small, single-center, and published in Russian-language journals, which limits independent scrutiny. Outcome measures vary between studies and often rely on clinician-rated scales rather than objective biomarkers. Systematic reviews have noted the methodological weaknesses and called for larger, preregistered trials before firm conclusions can be drawn.
Claims about enhanced focus, memory, or mood in healthy people rest mostly on anecdotal reports and community discussion rather than on controlled data. It remains unclear whether any cognitive benefit observed in patients recovering from brain injury would extend to uninjured users. Dose-response relationships, long-term safety, and interactions with other drugs are not well characterized in the peer-reviewed literature. Questions about optimal route of administration and treatment duration likewise remain open.
| Property | Value | Notes |
|---|---|---|
| Molecular class | Synthetic heptapeptide | Analog of an ACTH fragment |
| Amino acid length | Seven residues | Met-Glu-His-Phe-Pro-Gly-Pro |
| Origin | Moscow, 1980s | Institute of Molecular Genetics |
| Approved regions | Russia and some neighboring states | Not cleared in Western markets |
| Common trade names | Multiple national brands | Sold as a nasal formulation |
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.
Once dissolved, the peptide is considerably less stable than the solid. Aqueous solutions are usually prepared at neutral to slightly acidic pH, filtered, and divided into single-use aliquots before freezing. Repeated freeze-thaw cycles are a common cause of avoidable loss and are best prevented by never refreezing a thawed aliquot. Adsorption to plastic and glass surfaces can lower the measured concentration of dilute solutions, particularly below roughly 0.1 mg/mL. Buffer choice, salt content, and container material all influence how much peptide remains detectable after storage.
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 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.
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.
Identity and purity are confirmed with reversed-phase high-performance liquid chromatography, typically monitored at 214 nanometres where the peptide bond absorbs. Mass spectrometry, either electrospray or MALDI-TOF, verifies molecular mass against the theoretical value and detects truncation or adduct formation. Amino acid analysis and peptide mapping provide additional confirmation when required. The most frequently reported impurities are deletion sequences from incomplete coupling, methionine sulfoxide from oxidation, and dimeric species formed through non-covalent aggregation. Impurity profiles depend strongly on the synthesis and purification route chosen by the producer.
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.
== Use == Carrel and Dakin used a variety of apparatuses to infuse the solution continuously over the wounds. In modern typical usage, the solution is applied to the wound once daily for lightly to moderately exudative wounds, and twice daily for heavily exudative wounds or highly contaminated wounds. The healthy skin surrounding the wound should preferably be protected with a moisture barrier ointment (e.g., petroleum jelly) or skin sealant as needed to prevent irritation.
Although with only one exception (the amoeboid Paulinella chromatophora), all chloroplasts can be traced back to a single endosymbiotic event they can be found in extremely diverse organisms that are not directly related to each other—a consequence of many secondary and even tertiary endosymbiotic events.
=== Text mining methods === Publicly available information from biomedical documents is readily accessible through the internet and is becoming a powerful resource for collecting known protein–protein interactions (PPIs), PPI prediction and protein docking. Text mining is much less costly and time-consuming compared to other high-throughput techniques. Currently, text mining methods generally detect binary relations between interacting proteins from individual sentences using rule/pattern-based information extraction and machine learning approaches. A wide variety of text mining applications for PPI extraction and/or prediction are available for public use, as well as repositories which often store manually validated and/or computationally predicted PPIs. Text mining can be implemented in two stages: information retrieval, where texts containing names of either or both interacting proteins are retrieved and information extraction, where targeted information (interacting proteins, implicated residues, interaction types, etc.) is extracted. There are also studies using phylogenetic profiling, basing their functionalities on the theory that proteins involved in common pathways co-evolve in a correlated fashion across species. Some more complex text mining methodologies use advanced Natural Language Processing (NLP) techniques and build knowledge networks (for example, considering gene names as nodes and verbs as edges). Other developments involve kernel methods to predict protein interactions.
Sources: en.wikipedia.org
Animal hearts are widely consumed as a type of offal. As they are almost entirely muscle, they are high in protein. They are often included in dishes with other internal organs, for example in the pan-Ottoman kokoretsi. Chicken hearts are considered to be giblets, and are often grilled on skewers; examples of this are Japanese hāto yakitori, Brazilian churrasco de coração, and Indonesian chicken heart satay. They can also be pan-fried, as in Jerusalem mixed grill. In Egyptian cuisine, they can be used, finely chopped, as part of stuffing for chicken. Many recipes combined them with other giblets, such as the Mexican pollo en menudencias and the Russian ragu iz kurinyikh potrokhov. As heart is a hard-working muscle, it makes for "firm and rather dry" meat, so is generally slow-cooked. Another way of dealing with toughness is to julienne the meat, as in Chinese stir-fried heart. Beef heart is valued for its high meat quality and low price, being commonly disregarded in conventional meat pricing. It can be cut into steaks, comparable in quality to the more expensive cuts of meat from the same animal, though it is distinguished by a lack of a discernible grain. It was historically eaten in the United States as a cost-saving measure, but is today also eaten as an independently desirable ingredient. Beef heart may be grilled or braised. In the Peruvian anticuchos de corazón, barbecued beef hearts are grilled after being tenderized through long marination in a spice and vinegar mixture. An Australian recipe for "mock goose" is actually braised stuffed beef heart.
Coeliac disease is a systemic disorder, meaning it affects the entire body. Although many common symptoms of the disease are related to the gastrointestinal tract, those with coeliac disease may also experience symptoms and complications in other organs, known as extraintestinal manifestations. These manifestations may be related to malabsorption or systemic inflammation. Common extraintestinal manifestations of coeliac disease include headaches, fatigue, brain fog, muscle pain, and joint pain. Nutritional status in coeliac disease may be compromised due to lower intake, maldigestion, and malabsorption, leading to nutritional deficiencies. Common deficiencies in coeliac disease include iron, folate, zinc, vitamin D, and vitamin B12. Vitamin D deficiency can cause secondary hyperparathyroidism. Hyperoxaluria and kidney stones can be caused by malabsorption of fats, and peptides. Iron deficiency may lead to anaemia, which is one of the most common extraintestinal presentations of coeliac disease. Coeliac disease also often affects the bones, causing low bone mass density (osteopenia) and osteoporosis. Causes of bone changes in coeliac disease are believed to be caused by malabsorption, inflammation, and autoimmunity. If left untreated, coeliac disease can affect hormones, causing delayed periods or puberty and reproductive disorders. Coeliac disease is associated with infertility and complications during pregnancy such as intra-uterine growth restriction and spontaneous abortion.
=== Basement membrane zone === In the skin the basement membrane that separates, and connects the epidermis and the underlying dermis is part of a complex and specialized structure called the basement membrane zone (BMZ). The BMZ has four distinct layers – the basal cell layer, the lamina lucida, the lamina densa, and the sublaminal densa, and has many functions. Tiny microfilaments called tonofilaments cross the basal cell layer, and extend to the epidermal part of the hemidesmosome. Laminins and other adherence proteins are located in the lamina lucida. The lamina densa is mostly composed of a type IV collagen scaffold. Anchoring fibrils and microfilaments extend and blend with the elastic fibrillary system of the dermis. The components of the BMZ form a complex, functional network that extends from the basal epidermal keratinocytes and their hemidesmosomes, and include anchoring fibrils from the lamina densa, into the extracellular matrix (ECM) of the dermis. In the ECM the anchoring fibrils appear as cross-striated fibrous masses. There are also focal adhesion complexes on the outer cell membrane that bind the cytoskeleton to cell-matrix adhesions.
Sources: en.wikipedia.org
This is a shortened version of the second chapter of the ICD-9: Neoplasms. It covers ICD codes 140 to 239. The full chapter can be found on pages 101 to 144 of Volume 1, which contains all (sub)categories of the ICD-9. Volume 2 is an alphabetical index of Volume 1. Both volumes can be downloaded for free from the website of the World Health Organization. See here for a tabular overview of primary, secondary, in situ, and benign neoplasms.
== Equilibria Among Multiple Reactions == Consider the case of a dibasic acid H2A. When dissolved in water, the mixture will contain H2A, HA− and A2−. This equilibrium can be split into two steps in each of which one proton is liberated.
Penis or pizzle is a type of offal. In many cultures, it is a taboo food. Penis is eaten in some cultures or traditional medicine systems as a purported health food: it may be seen as an aphrodisiac, a cure for sexual dysfunction, a hangover cure, and more. Penis is often paired with testicles as food.
During FY2018, the federal government spent $4.11 trillion, up $127 billion or 3.2% vs. FY2017 spending of $3.99 trillion. Spending increased for all major categories and was mainly driven by higher spending for Social Security, net interest on the debt, and defense. Spending as % GDP fell from 20.7% GDP to 20.3% GDP, equal to the 50-year average. During FY2017, the federal government spent $3.98 trillion, up $128 billion or 3.3% vs. FY2016 spending of $3.85 trillion. Major categories of FY 2017 spending included: Healthcare such as Medicare and Medicaid ($1,077B or 27% of spending), Social Security ($939B or 24%), non-defense discretionary spending used to run federal Departments and Agencies ($610B or 15%), Defense Department ($590B or 15%), and interest ($263B or 7%). Expenditures are classified as "mandatory", with payments required by specific laws to those meeting eligibility criteria (e.g., Social Security and Medicare), or "discretionary", with payment amounts renewed annually as part of the budget process. Around two thirds of federal spending is for "mandatory" programs. CBO projects that mandatory program spending and interest costs will rise relative to GDP over the 2016–2026 period, while defense and other discretionary spending will decline relative to GDP.
Sources: en.wikipedia.org
It originated at the Institute of Molecular Genetics in Moscow during the 1980s. The work was carried out by a Russian research group that specialized in peptide neuropharmacology.
It is registered as a medicine in Russia and has been used clinically there for decades. No regulatory agency in Western Europe or North America has approved it for any indication.
Semax corresponds to the four-to-ten fragment of adrenocorticotropic hormone. Because it omits the first three residues, it lacks the adrenal-stimulating action of the full hormone.
It is associated with the melanocortin receptor family, particularly subtypes found in the central nervous system. This interaction is separate from the adrenal pathway activated by full-length ACTH.