Neurotrophic factor comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Last reviewed on 2026-07-01. Where a claim depends on a specific study, the study is described rather than over-claimed.
Quantification in biological matrices relies on liquid chromatography coupled to tandem mass spectrometry with stable-isotope internal standards. Low plasma concentrations and adsorption to container surfaces both complicate measurement. Solid-phase extraction is often needed to reduce matrix interference before injection. Reported limits of quantification differ widely between laboratories, which makes direct comparison of pharmacokinetic results difficult and limits meta-analysis.
Peptide bonds are vulnerable to protease attack, and Selank is no exception. Measured half-life in serum is short, on the order of minutes in several reports, which explains why intranasal administration is the common route described in the literature. Absorption across the nasal mucosa partially bypasses first-pass hepatic metabolism. Quantitative data on human bioavailability remain limited and are difficult to compare across studies.
Handling follows standard practice for research peptides. Material is weighed in a low-humidity environment because the powder absorbs atmospheric moisture. Purity is reported as the percentage area of the main peak in a chromatogram, with specifications commonly set at 95 percent or higher; values below that threshold indicate the presence of truncated or modified species. Residual trifluoroacetate from purification is often present and may affect mass balance. Certificates of analysis should state the analytical method, the column and gradient used, and the lot-specific retention time so that results can be compared across suppliers.
Identity and purity of selank are established with reversed-phase high-performance liquid chromatography coupled to mass spectrometry. The peptide elutes from C18 columns with acetonitrile gradients in water containing trifluoroacetic acid or formic acid, and detection is usually performed by ultraviolet absorbance near 214 nm. Electrospray ionization in positive mode gives a doubly protonated ion near m/z 377, consistent with a mass of about 752 Da. Amino acid analysis or tandem mass spectrometry of fragment ions confirms the sequence. Because the molecule has no aromatic residues, it lacks a usable 280 nm chromophore, so low-wavelength detection or mass spectrometry is required.
| Property | Value | Notes |
|---|---|---|
| Dry storage temperature | -20 C or below | Sealed, desiccated, protected from light |
| Solution stability | Hours to days at 2-8 C | Depends on buffer and microbial load |
| Preferred pH range | Near neutral to slightly acidic | Alkaline pH accelerates hydrolysis |
| Main degradation routes | Hydrolysis and deamidation | No cysteine or methionine in sequence |
| Identity confirmation | Electrospray mass spectrometry | Observed mass compared with 751.9 Da |
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.
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.
Pharmacokinetic data are sparse and largely derived from animal work. After intranasal administration the peptide appears in plasma within minutes, and reported half-lives are short, on the order of minutes to tens of minutes. Degradation proceeds through ordinary proteolytic cleavage into constituent amino acids and smaller fragments. Direct evidence that intact Selank reaches brain tissue in meaningful amounts is limited, and the extent of blood-brain barrier penetration is debated. Some authors argue that fragments, not the parent peptide, carry much of the observed activity.
Published clinical work is concentrated in Russian-language journals and generally involves small samples without independent replication. Systematic reviews in English note the shortage of randomised, placebo-controlled trials and the difficulty of verifying methods from translated reports. Outcome measures vary between studies, which complicates pooling of results. Interest in the compound as a cognitive or anxiolytic agent therefore rests on a thinner evidence base than the volume of citations suggests. Replication in well-powered trials with preregistered endpoints would be needed before firm conclusions about efficacy can be drawn.
Proposed mechanisms centre on the GABAergic system. Animal and tissue studies report changes in GABA-A receptor expression and reduced activity of GABA transaminase, the enzyme that degrades GABA. Effects on monoamine turnover, including serotonin and dopamine pathways, are also described, and a separate line of work links the peptide to increased expression of brain-derived neurotrophic factor in hippocampal tissue. Most of these findings come from rodent models and cell preparations. How the individual observations combine into a single coherent mode of action is not settled.
Solubility behavior is a practical concern for handling. Selank dissolves readily in water and in common aqueous buffers, which simplifies preparation of working solutions. The choice of solvent, ionic strength, and pH can influence aggregation over time, particularly at higher concentrations. Aqueous solutions are typically sterile-filtered before use. Because stability depends on several variables, storage and handling notes should be treated as general guidance rather than fixed rules, and specific values are best confirmed against a certificate of analysis for each batch.
Characterization of Selank in a laboratory setting relies on standard peptide methods. Reverse-phase high-performance liquid chromatography separates the target from related impurities and provides a purity figure, commonly reported as 95 percent or higher. Mass spectrometry, typically electrospray ionization or matrix-assisted laser desorption, confirms the molecular mass and helps detect truncation or modification. Amino acid analysis can verify composition when a sequence-level check is needed. These techniques together establish identity and purity for a given lot.
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.
A range of algal morphologies is exhibited, and convergence of features in unrelated groups is common. The only groups to exhibit three-dimensional multicellular thalli are the reds and browns, and some chlorophytes. Apical growth is constrained to subsets of these groups: the florideophyte reds, various browns, and the charophytes. The form of charophytes is quite different from those of reds and browns, because they have distinct nodes, separated by internode 'stems'; whorls of branches reminiscent of the horsetails occur at the nodes. Conceptacles are another polyphyletic trait; they appear in the coralline algae and the Hildenbrandiales, as well as the browns. Most of the simpler algae are unicellular flagellates or amoeboids, but colonial and nonmotile forms have developed independently among several of the groups. Some of the more common organizational levels, more than one of which may occur in the lifecycle of a species, are
== History == Cortisone was first identified by the American chemists Edward Calvin Kendall and Harold L. Mason while researching at the Mayo Clinic. During the discovery process, cortisone was known as compound E (while cortisol was known as compound F). In 1949, Philip S. Hench and colleagues discovered that large doses of injected cortisone were effective in the treatment of patients with severe rheumatoid arthritis. Kendall was awarded the 1950 Nobel Prize for Physiology or Medicine along with Philip Showalter Hench and Tadeusz Reichstein for the discovery of the structure and function of adrenal cortex hormones including cortisone. Both Reichstein and the team of O. Wintersteiner and J. Pfiffner had separately isolated the compound prior to the discovery made by Mason and Kendall, but failed to recognize its biological significance. Mason's contributions to the crystallization and characterization of the compound have generally been forgotten outside of the Mayo Clinic. Cortisone was first produced commercially by Merck & Co. in 1948 or 1949. On September 30, 1949, Percy Julian announced an improvement in the process of producing cortisone from bile acids. This eliminated the need to use osmium tetroxide, a rare, expensive, and dangerous chemical. In the UK in the early 1950s, John Cornforth and Kenneth Callow at the National Institute for Medical Research collaborated with Glaxo to produce cortisone from hecogenin from sisal plants.
Prescription-only medicines (POM), which may be dispensed (sold in the case of a private prescription) by a pharmacist only to those to whom they have been prescribed Pharmacy medicines (P), which may be sold by a pharmacist without a prescription General sales list (GSL) medicines, which may be sold without a prescription in any shop The simple possession of a prescription-only medicine without a prescription is legal unless it is covered by the Misuse of Drugs Act 1971. A patient visits a medical practitioner or dentist, who may prescribe drugs and certain other medical items, such as blood glucose-testing equipment for diabetics. Also, qualified and experienced nurses, paramedics and pharmacists may be independent prescribers. Both may prescribe all POMs (including controlled drugs), but may not prescribe Schedule 1 controlled drugs, and 3 listed controlled drugs for the treatment of addiction; which is similar to doctors, who require a special licence from the Home Office to prescribe schedule 1 drugs. Schedule 1 drugs have little or no medical benefit, hence their limitations on prescribing. District nurses and health visitors have had limited prescribing rights since the mid-1990s; until then, prescriptions for dressings and simple medicines had to be signed by a doctor. Once issued, a prescription is taken by the patient to a pharmacy, which dispenses the medicine. Most prescriptions are NHS prescriptions, subject to a standard charge that is unrelated to what is dispensed.
Wounded healer is a term created by psychiatrist Carl Jung. The idea states that an analyst is compelled to treat patients because the analyst himself is "wounded." The idea may have Greek mythology origins. Victor et al. (2022) found that 82% of applied psychology graduate students and faculty members in the United States and Canada experienced mental health conditions at some point in their lives. As an example, of the "wounded healer phenomenon" between an analyst and their analyzed:
Food and Drug Administration concluded that TDA-induced breast cancer was an infinitesimal health-risk to women with breast implants, and did not justify legally requiring physicians to explain the matter to their patients. In the event, polyurethane-coated breast implants remain in plastic surgery practice in Europe and in South America; and no manufacturer has sought FDA approval for medical sales of such breast implants in the U.S.
Sources: en.wikipedia.org
=== Lucinda Young === Lucinda Young (Ruby Bentall) is a VP on Pierpoint's Investment Banking Division (IBD), overseeing Gus and Hari. She tacitly encourages Hari to overwork during his first week on the job; after Hari dies of a heart attack, Lucinda feels guilty, and worries whether she will be held culpable for Hari's death, telling Gus to vouch for her with HR. Lucinda is briefly seen in series 2 meeting with executives from healthcare startup Rican, for whom Pierpoint is helping engineer a major trade.
== See also == Baby Friendly Hospital Initiative Breastfeeding promotion Breastfeeding contraindications Haberman Feeder Infant formula International Code of Marketing of Breast-milk Substitutes List of bottle types, brands and companies
== Mechanism of action == The principal mechanism of the epothilone class is the inhibition of the microtubule function. Microtubules are essential to cell division, and epothilones, therefore, stop cells from properly dividing. Epothilone B possesses the same biological effects as paclitaxel both in vitro and in cultured cells. This is because they share the same binding site, as well as binding affinity to the microtubule. Like paclitaxel, epothilone B binds to the αβ-tubulin heterodimer subunit. Once bound, the rate of αβ-tubulin dissociation decreases, thus stabilizing the microtubules. Furthermore, epothilone B has also been shown to induce tubulin polymerization into microtubules without the presence of GTP. This is caused by the formation of microtubule bundles throughout the cytoplasm. Finally, epothilone B also causes cell cycle arrest at the G2-M transition phase, thus leading to cytotoxicity and eventually cell apoptosis. The ability of epothilone to inhibit spindle function is generally attributed to its suppression of microtubule dynamics; but recent studies have demonstrated that suppression of dynamics occurs at concentrations lower than those needed to block mitosis. At higher antimitotic concentrations, paclitaxel appears to act by suppressing microtubule detachment from centrosomes, a process that is normally activated during mitosis. It is quite possible that epothilone can also act through a similar mechanism.
This step is the enzymatic transfer of a phosphate group from 1,3-bisphosphoglycerate to ADP by phosphoglycerate kinase, forming ATP and 3-phosphoglycerate. At this step, glycolysis has reached the break-even point: 2 molecules of ATP were consumed, and 2 new molecules have now been synthesized. This step, one of the two substrate-level phosphorylation steps, requires ADP; thus, when the cell has plenty of ATP (and little ADP), this reaction does not occur. Because ATP decays relatively quickly when it is not metabolized, this is an important regulatory point in the glycolytic pathway. ADP actually exists as ADPMg−, and ATP as ATPMg2−, balancing the charges at −5 both sides. Cofactors: Mg2+
Explorers, traders and missionaries arrived from Russia beginning in 1741. In 1741 the Russian government sent Vitus Bering, a Danish-born Russian, and Aleksei Chirikov, a Russian, in the ships Saint Peter and Saint Paul on a voyage of discovery in the Northern Pacific. After the ships were separated by a storm; Chirikov discovered several eastern islands of the Aleutian group, and Bering discovered several of the western islands. Bering was shipwrecked and died in the Komandorski Islands (Commander Islands); one of which now bears his name (Bering Island), along with the surrounding Bering Sea. The survivors of Bering's party reached the Kamchatka Peninsula in a boat constructed from the wreckage of their ship, and reported the islands were rich in fur-bearing animals. Siberian fur hunters flocked to the Commander Islands and gradually moved eastward across the Aleutian Islands to North America. In this manner, Russia gained a foothold on the northwestern coast of North America. The Aleutian Islands consequently belonged to Russia, until that country transferred all its possessions in North America to the U.S. in the 1867 Alaska Purchase. In the 1780s Russian merchant and seafarer Grigory Shelikhov established a company based on the systematic exploitation of the indigenous peoples, with whom there was sporadic conflict with the native population, for example the Awa'uq Massacre.
Sources: en.wikipedia.org
Dry powder is best kept sealed, protected from light, and held at minus 20 degrees Celsius or below. Desiccant packaging helps limit moisture uptake because the material is hygroscopic. A sealed vial should be allowed to equilibrate to room temperature before opening to reduce condensation.
Hydrolysis of peptide bonds and deamidation of arginine and proline residues are the main degradation routes. Alkaline pH and higher temperatures accelerate both processes. Buffered, near-neutral solutions stored cold generally degrade more slowly than unbuffered ones.
Reverse-phase chromatography gives the clearest single view of related impurities and truncated sequences. Mass spectrometry then confirms that the main peak carries the expected mass. Neither test detects enantiomeric impurities, which require a separate chiral assay.
Identity is confirmed by matching the retention time in reversed-phase chromatography against a reference standard and by measuring the molecular mass with mass spectrometry. Tandem mass spectrometry or amino acid analysis can verify the sequence of the seven residues. Because the peptide contains no aromatic amino acids, detection at 280 nm is not useful.