tuftsin raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2026-01-20. Anything still debated is marked as such rather than presented as settled.
Published work on this peptide almost always uses intranasal delivery, with drops or a spray applied to the nasal mucosa. Some animal experiments have used subcutaneous or intraperitoneal injection, and a smaller number have compared routes directly. Oral administration is not a focus of the literature, because short peptides of this size are broken down by digestive enzymes and cross intestinal barriers poorly. How much of an intranasal dose reaches the bloodstream intact in humans remains an open question.
Animal studies have examined behaviour in tests of anxiety, memory retention and stress response, and several report changes in neurotrophic or neurotransmitter-related markers. The human evidence base is much smaller, consisting mainly of short trials conducted in Russia with limited reporting in English-language journals. Sample sizes are modest and outcome measures vary between studies, so the findings are best described as preliminary. Independent replication under modern trial standards has not been widely reported.
Outside its country of origin the compound is generally handled as a research chemical rather than an approved medicine. No regulatory approval from the United States Food and Drug Administration or the European Medicines Agency has been granted for human use. Identity and purity are normally checked by reverse-phase high-performance liquid chromatography, with mass spectrometry used to confirm the molecular mass. Lyophilised material is stored cold and desiccated, and repeated freeze-thaw cycles are avoided.
Proposed mechanisms centre on modulation of the GABAergic system, with reports of altered expression of genes related to GABA-A receptor subunits and changed monoamine turnover. Some studies describe inhibition of enkephalinase, the enzyme that degrades endogenous enkephalins, which may prolong opioid peptide signalling. Effects on brain-derived neurotrophic factor and on cytokine expression have also been reported. These findings come largely from animal models and small human studies, and the precise primary target remains unresolved.
Published clinical evidence is limited. Most controlled trials were conducted in Russia, enrolled modest numbers of participants, and appeared in Russian-language journals, which restricts independent verification. Reported outcomes include lower anxiety scores, improved attention and memory measures, and changes in fatigue ratings. Reviews written in English note methodological limitations such as small samples and inconsistent endpoints. Whether the compound produces clinically meaningful benefit relative to established anxiolytics is therefore an open question rather than an established finding.
| Property | Value | Notes |
|---|---|---|
| Common route | Intranasal | Also injected in some animal work |
| Solubility class | Freely soluble in water | Solid form is hygroscopic |
| Typical storage | About -20 degrees Celsius | Keep desiccated and dark |
| Purity method | Reverse-phase HPLC | Reported as area percent |
| Confirmatory method | Mass spectrometry | Verifies expected molecular mass |
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro. It was designed as a stabilized analogue of tuftsin, a naturally occurring tetrapeptide fragment derived from the immunoglobulin heavy chain. The additional Pro-Gly-Pro segment at the carboxyl terminus is intended to slow enzymatic cleavage. The compound is usually described in the literature as a synthetic peptide with anxiolytic and cognitive-related activity, a label that reflects a research context rather than an approved therapeutic category.
Most published work on selank originates from a small number of research groups in the Russian Federation. A large share of that record appears in Russian-language journals, which limits access for readers who rely on English-indexed databases. Independent replication by laboratories outside the original research network is sparse in publicly available sources. This concentration of origin and language is a frequently noted feature when the compound is summarized in broader reviews of synthetic peptides.
Reported pharmacological effects center on reduced anxiety-like behavior in animal models and on measures of memory and learning. Proposed contributing mechanisms include modulation of GABAergic signaling, shifts in monoamine turnover, and changes in the activity of enzymes that degrade neuropeptides. Effects on the expression of genes linked to neuroplasticity have also been described. No single molecular target is widely accepted, and whether the behavioral findings arise from one pathway or several remains an open question.
Selank is a synthetic heptapeptide developed in Russia as a structural analogue of tuftsin, a naturally occurring immunomodulatory tetrapeptide. Its sequence, Thr-Lys-Pro-Arg-Pro-Gly-Pro, keeps the tuftsin core at the N-terminus and appends a Pro-Gly-Pro tail. Researchers at the Institute of Molecular Genetics in Moscow synthesized the compound during the 1990s while searching for peptides with combined anxiolytic and immunomodulatory activity. The added tail was intended to resist enzymatic cleavage and prolong the molecule's presence in circulation.
The compound has a calculated molecular weight near 751.9 daltons and carries a net positive charge at physiological pH because of its arginine residue. It dissolves freely in water and in common aqueous buffers, and typically appears as a white or off-white lyophilized powder. The amide backbone makes the molecule susceptible to peptidases, which limits oral use and favors intranasal or parenteral routes. Nomenclature in the literature varies: the substance is also described by the sequence abbreviation TP-7 and by a Russian trade designation.
Regulatory status differs sharply by region. Selank holds a Russian marketing authorization, where it is supplied mainly as nasal drops, while authorities elsewhere have not approved it for medical use. Material sold internationally is therefore usually labeled as a research chemical rather than a medicine. Peer-reviewed publications come predominantly from Russian laboratories, and sample sizes are generally small. Whether the compound produces comparable effects under independent, well-controlled replication remains an open question that the broader literature has not settled.
Pharmacokinetic data are limited. Like most short peptides, Selank is vulnerable to plasma and tissue peptidases, and its measured half-life in circulation is short, on a minutes scale. The Pro-Gly-Pro tail slows this degradation but does not eliminate it. Intranasal administration is the route described in most reports, with absorption through the nasal mucosa and a hypothesized path into the central nervous system that avoids the blood-brain barrier. Direct measurements of human brain exposure are unavailable, so distribution claims rest on inference from animal work.
Clinical evidence comes mainly from small studies conducted in Russia, several of which were open-label or lacked robust blinding. Reported outcomes include lower anxiety scores, changes in attention measures, and effects on asthenic states following illness. Sample sizes are typically in the tens of participants, and independent replication outside the region is scarce. Reviews published in English generally note the limited methodological quality of the underlying trials. Whether the compound produces clinically meaningful effects under rigorous conditions remains unresolved.
The flow through compressors, see schematic, is controlled by measuring the flow (FT) through the machine at the suction and controlling the speed (SC) of the prime mover (electric motor or gas turbine) that is driving the compressor. Anti-surge control ensures a minimum flow of fluid through the compressor. The flow (FT) at the discharge and measurements of the suction and discharge pressures (PT) and temperatures (TT) of the fluid flowing through the compressor are measured. The anti-surge controller (FIC) modulates a control valve (FCV) which recycles cooled gas from downstream of the compressor after-cooler back to the suction of the compressor. Low flow alarms (FAL) provide a warning indication to operating personnel.
=== Nerve cell === Nerve cells comprise a small cell body and a very long segment called the axon. The cell body resides in the spinal cord and the axon extends all the way to the innervation target of the nerve. Peripheral nerve axons can be longer than 100 cm as they may need to travel along the full length of a limb to reach their innervation target, while the cell body is only 100 micrometers long. Nerves may be myelinated or unmyelinated. Myelinated nerves have the axon covered by segments of schwann cells, which are short and concentrically wrapped around the diameter of an axon to give the appearance of a sausage-like mass and called a myelin sheath. The schwann cells are arranged in pattern such all parts of the axon are wrapped in schwann cells and successive schwann cells are separated by a very small distance. This separation gap is called a node of Ranvier. Unmyelinated nerves are also surrounded by schwann cells but the schwann cells are not wrapped around the axon multiple times to form a myelin sheath.
== Contraindications == Methamphetamine is contraindicated in individuals with a history of substance use disorder, heart disease, or severe agitation or anxiety, or in individuals currently experiencing arteriosclerosis, glaucoma, hyperthyroidism, or severe hypertension. The FDA states that individuals who have experienced hypersensitivity reactions to other stimulants in the past or are currently taking monoamine oxidase inhibitors should not take methamphetamine. The FDA also advises individuals with bipolar disorder, depression, elevated blood pressure, liver or kidney problems, mania, psychosis, Raynaud's phenomenon, seizures, thyroid problems, tics, or Tourette syndrome to monitor their symptoms while taking methamphetamine. Owing to the potential for stunted growth, the FDA advises monitoring the height and weight of growing children and adolescents during treatment.
Recent size estimates in 2023 have this sauropod reaching lengths of up to 44 m (144 ft) long and placed in a colossal weight range of around 110000–170000 kg (240000–370000 lb). If these upper estimates are true, Bruhathkayosaurus would have rivaled the blue whale and Perucetus colossus as one of the largest animals to have ever existed. The largest carnivorous dinosaur was Spinosaurus, reaching a length of 12.6 to 18 meters (41 to 59 ft) and weighing 7 to 20.9 metric tons (7.7 to 23.0 short tons). Other large carnivorous theropods included Giganotosaurus, Carcharodontosaurus, and Tyrannosaurus. Therizinosaurus and Deinocheirus were among the tallest of the theropods. The largest ornithischian dinosaur was probably the hadrosaurid Shantungosaurus giganteus, which measured 16.6 meters (54 ft). The largest individuals may have weighed as much as 16 metric tons (18 short tons).
Sources: en.wikipedia.org
Jesus himself identifies John as "Elijah who is to come", which is a direct reference to the Book of Malachi (Malachi 4:5), that has been confirmed by the angel who announced John's birth to his father, Zechariah. According to the Gospel of Luke, John and Jesus were relatives. Saint George was a Christian who is venerated as a saint in Christianity, and he was a soldier of Cappadocian Greek origin and member of the Praetorian Guard for Roman emperor Diocletian, who was sentenced to death for refusing to recant his Christian faith. He became one of the most venerated saints and megalomartyrs in Christendom, and he has been especially venerated as a military saint since the Crusades. In hagiography, as one of the Fourteen Holy Helpers and one of the most prominent military saints, he is immortalized in the legend of Saint George and the Dragon. His memorial, Saint George's Day, is traditionally celebrated on 23 April. England, Ethiopia, Georgia, Catalonia and Aragon in Spain, Moscow in Russia, and several other states, regions, cities, universities, professions and organizations claim George as their patron. The bones of Saint George are buried in the Church of Saint George, Lod, Israel.
== Recording and production == Reek of Putrefaction was recorded in four days at Rich Bitch Studios in Birmingham. According to guitarist Bill Steer, the studio's engineer "ruined" the record, especially its drum tracks. Carcass had only had a few hours available of mixing, so they had to release the LP as it was to meet the label's deadline. The band were "everything but happy" with the result, declared Steer. When the master recording was first sent to the pressing plant, the original vinyl LP had to be pressed at lower volumes, because the bass frequencies were so low (sometimes reaching 25 Hz) that they were in danger of rendering higher frequencies inaudible.
=== Conversion of UDP-galactose to UDP-glucose === GALE inverts the configuration of the 4' hydroxyl group of UDP-galactose through a series of 4 steps. Upon binding UDP-galactose, a conserved tyrosine residue in the active site abstracts a proton from the 4' hydroxyl group. Concomitantly, the 4' hydride is added to the si-face of NAD+, generating NADH and a 4-ketopyranose intermediate. The 4-ketopyranose intermediate rotates 180° about the pyrophosphoryl linkage between the glycosyl oxygen and β-phosphorus atom, presenting the opposite face of the ketopyranose intermediate to NADH. Hydride transfer from NADH to this opposite face inverts the stereochemistry of the 4' center. The conserved tyrosine residue then donates its proton, regenerating the 4' hydroxyl group.
Sources: en.wikipedia.org
Susan E. Leeman (May 9, 1930 – January 20, 2026) was an American endocrinologist who was renowned for her research on peptides. Leeman was a professor in the Department of Pharmacology and Experimental Therapeutics at Boston University. She continued to work into her nineties and later served as the director of the Neuropeptide Laboratory in the Pharmacology Department at the Chobanian and Avedisian School of Medicine. Her work with substance P and neurotensin, both of which are peptides crucial to the function of the nervous, endocrine, and immune systems, led to her becoming considered one of the pioneers of neuroendocrinology. Her later research focused on substance P specifically and how it binds with its receptor. Leeman was elected as a member within the National Academy of Sciences in 1991 and received the academy's Fred Conrad Koch Award in 1994. Leeman was a member of the Endocrine Society, Society for Neuroscience, American Association for the Advancement of Science, and American Physiological Society.
== Diuretics and masking agents == Diuretics, sometimes known as ‘water pills,’ are drugs that alter the body's fluid and salt balance, increasing urine production. They are used for the swelling and bloating of premenstrual syndrome, for treating high blood pressure, and in older people for heart failure caused by weakening of the heart's pumping mechanism. Diuretics can be used to pass a drug test because they increase the amount of urine produced by the body, thereby it dilutes any drugs in the urine which makes it harder to identify them. Examples of diuretics and masking agents are bumetanide, chlorothiazide, furosemide, hydrochlorothiazide, probenecid, spironolactone (canrenone), triameterene, and trichlormethiazide. Finasteride is not banned.
=== Flavoring agents === A large number of pyridine compounds are approved as flavoring agents in the EU. These include the three isomeric picolines and several lutidines. Selected representatives are listed in the following table.
Sources: en.wikipedia.org
Most published work uses intranasal application, either as drops or as a nasal spray. Injection routes appear in a smaller set of animal experiments. Oral use is uncommon in the literature because peptide breakdown and poor absorption limit this route.
Reported human trials are few, brief and originate mainly from one country. They describe effects on anxiety-related measures, but sample sizes are small and reporting is limited. The results are widely regarded as preliminary rather than confirmed.
Reverse-phase liquid chromatography is used to assess purity and separation of related impurities. Mass spectrometry confirms that the observed molecular mass matches the expected peptide. A certificate of analysis from the supplier is the usual document of record.
It is a seven-amino-acid peptide, Thr-Lys-Pro-Arg-Pro-Gly-Pro, produced by chemical synthesis rather than extracted from biological tissue. Its design is based on tuftsin, a natural immunomodulatory tetrapeptide. The C-terminal Pro-Gly-Pro segment is a common stabilising motif in short regulatory peptides.