Everything below concerns freeze-thaw. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2025-09-25. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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.
Lyophilized Selank, the dry powder form, is generally stored frozen at minus 20 degrees Celsius or colder for long-term keeping. The solid is hygroscopic and should stay sealed, dry, and protected from light. Once dissolved, the peptide is less stable and is usually held refrigerated at 2 to 8 degrees Celsius for short periods. Repeated freezing and thawing is avoided because it can promote aggregation and loss of activity. Buffers and pH choice also affect how long a solution remains usable.
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.
| 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 at the Institute of Molecular Genetics of the Russian Academy of Sciences as a structural analogue of tuftsin, a naturally occurring tetrapeptide fragment of the immunoglobulin heavy chain. The added Pro-Gly-Pro tail was intended to slow enzymatic degradation and extend biological activity. In Russia it is registered as an anxiolytic nasal preparation, while regulators elsewhere have not approved it for clinical use.
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.
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro. Its four N-terminal residues reproduce tuftsin, a tetrapeptide fragment of the immunoglobulin heavy chain, while the C-terminal Pro-Gly-Pro extension is a synthetic addition. The peptide has a molecular mass near 752 daltons and carries a net positive charge at physiological pH because of the arginine and lysine side chains. Published indexes list it under the name Selank and the sequence abbreviation TKPRPGP. Solid-phase peptide synthesis is the standard production route for research quantities.
Development took place at the Institute of Molecular Genetics of the Russian Academy of Sciences, where a series of short peptides were designed in the 1980s and 1990s. Selank was selected from variants of tuftsin that showed resistance to plasma peptidases. Russian regulatory approval covers it as an anxiolytic agent given intranasally. Outside that market the compound is normally handled as a research chemical rather than a medicine, and no widely recognised international pharmacopoeial monograph exists. The name Selank is a coined trade designation rather than a systematic chemical name.
=== Other === The use of honey has been recommended as a temporary intervention for known or suspected button cell battery ingestions to reduce the risk and severity of injury to the esophagus caused by the battery prior to its removal. There is no evidence that honey is beneficial for treating cancer, although honey may be useful for controlling side effects of radiation therapy or chemotherapy used to treat cancer. Consumption is sometimes advocated as a treatment for seasonal allergies due to pollen, but scientific evidence to support the claim is inconclusive. Honey is generally considered ineffective for the treatment of allergic conjunctivitis. Honey has a mild laxative effect which has been noted as being helpful in alleviating constipation and bloating.
Another potential geopolitical issue that is considered particularly worrisome by military analysts is a possible conflict between the United States and the People's Republic of China over Taiwan. Although economic forces are thought to have reduced the possibility of a military conflict, there remains concern about the increasing military buildup of China (China is rapidly increasing its naval capacity), and that any move toward Taiwan independence could potentially spin out of control. Israel is thought to possess somewhere between one hundred and four hundred nuclear warheads. It has been asserted that the Dolphin-class submarines which Israel received from Germany have been adapted to carry nuclear-armed Popeye cruise missiles, so as to give Israel a second strike capability. Israel has been involved in wars with its neighbors in the Middle East (and with other "non-state actors" in Lebanon and Palestine) on numerous prior occasions, and its small geographic size and population could mean that, in the event of future wars, the Israel Defense Forces might have very little time to react to an invasion or other major threat. Such a situation could escalate to nuclear warfare very quickly in some scenarios. On March 7, 2013, North Korea threatened the United States with a pre-emptive nuclear strike. On April 9, North Korea urged foreigners to leave South Korea, stating that both countries were on the verge of nuclear war. On April 12, North Korea stated that a nuclear war was unavoidable. The country declared Japan as its first target.
=== Historical subdivisions === Between 1946 and 2004, the state's districts and independent towns were grouped into eight regions, with a different status for two regions (Verwaltungsbezirke), comprising the formerly free states of Brunswick and Oldenburg. In 1978 these regions were merged into four governorates (Regierungsbezirke). In 2005 the Bezirksregierungen (regional governments) were again split into separate bodies. 1946–1978:
Sources: en.wikipedia.org
== Early life == He is the fifth son of Sheikh Zayed bin Sultan Al Nahyan, the founder and first President of the United Arab Emirates. His mother is Sheikha Fatima bint Mubarak Al Ketbi and he has five full-brothers: Mohammed, Hamdan, Tahnoun, Mansour, and Abdullah.
=== Nonsteroidal anti-inflammatory drugs === Although individual analgesics rarely induce liver damage due to their widespread use, NSAIDs have emerged as a major group of drugs exhibiting hepatotoxicity. Both dose-dependent and idiosyncratic reactions have been documented. Aspirin and phenylbutazone are associated with intrinsic hepatotoxicity; idiosyncratic reaction has been associated with ibuprofen, sulindac, phenylbutazone, piroxicam, diclofenac and indomethacin.
=== Match schedule === The match schedule, without group assignments, was announced on February 4, 2024. On June 13, FIFA released an updated schedule, with specific pairings assigned to venues for the knockout stage. The full schedule was unveiled in a live broadcast on December 6, 2025, the day after the draw. The opening match of the tournament included Mexico, and took place on June 11, 2026, at the Estadio Azteca in Mexico City. Canada's first match occurred on June 12 at BMO Field in Toronto, while the United States' opening match took place on the same day at SoFi Stadium in Inglewood. The national team of each host nation played its three group stage matches in its own country. AT&T Stadium in Arlington hosted the most matches of any venue, with nine. The U.S. hosted 78 matches, including all quarterfinals, semifinals, and the final, which was played at MetLife Stadium in East Rutherford on July 19. Canada and Mexico each hosted 13 matches. Each tournament venue, except for the Estadio Akron, hosted at least one knockout stage match. The match schedule overlapped with the 2026 Canadian Football League season, resulting in scheduling conflicts and loss of home games for the Toronto Argonauts and BC Lions. The match schedule also affected the 2026 Major League Baseball season schedules of the Kansas City Royals, Philadelphia Phillies, Seattle Mariners, and Texas Rangers, with home stadiums near World Cup venues. Host cities were geographically grouped into three regions:
Sources: en.wikipedia.org
On June 28, 2007, the FARC suddenly reported the death of 11 of the 12 kidnapped provincial deputies from Valle del Cauca Department. The Colombian government accused the FARC of executing the hostages and stated that government forces had not made any rescue attempts. FARC claimed that the deaths occurred during a crossfire, after an attack on one of its camps by an "unidentified military group". FARC did not report any other casualties on either side. In 2007, Venezuelan President Hugo Chávez and Colombian Senator Piedad Córdoba were acting as authorised mediators in the ongoing humanitarian exchange between the FARC and the government of Colombia. Colombian President Álvaro Uribe had given Chávez permission to mediate under the conditions that all meetings with the FARC would take place in Venezuela and that Chávez would not contact members of the Colombian military directly but instead would go through proper diplomatic channels. However, President Uribe abruptly terminated Chávez's mediation efforts on November 22, 2007, after Chávez personally contacted General Mario Montoya Uribe, the Commander of the Colombian National Army. In response, Chávez said that he was still willing to mediate, but had withdrawn Venezuela's ambassador to Colombia and placed Colombian-Venezuelan relations "in a freezer". President Uribe responded by accusing Chávez of legitimizing terrorism and pursuing an expansionist project on the continent.
== Adoption and competitors == OC/RDC are used in academic and government networks, as well as in corporate environments. Other products in the same or adjacent space include Medidata Rave, REDCap, and Veeva Vault EDC.
==== Mass spectrometry–based methods ==== In mass spectroscopy-based proteomics there are three major steps needed for peptide identification: sample preparation, separation of peptides, and identification of peptides. Several groups have focused on oocytes or very early cleavage-stage cells since these cells are unusually large and provide enough material for analysis. Another approach, single cell proteomics by mass spectrometry (SCoPE-MS) has quantified thousands of proteins in mammalian cells with typical cell sizes (diameter of 10-15 μm) by combining carrier-cells and single-cell barcoding. The second generation, SCoPE2, increased the throughput by automated and miniaturized sample preparation; It also improved quantitative reliability and proteome coverage by data-driven optimization of LC-MS/MS and peptide identification. The sensitivity and consistency of these methods have been further improved by prioritization, and massively parallel sample preparation in nanoliter size droplets. Another direction for single-cell protein analysis is based on a scalable framework of multiplexed data-independent acquisition (plexDIA) enables time saving by parallel analysis of both peptide ions and protein samples, thereby realizing multiplicative gains in throughput. The separation of differently sized proteins can be accomplished by using capillary electrophoresis (CE) or liquid chromatography (LC) (using liquid chromatography with mass spectroscopy is also known as LC-MS). This step gives order to the peptides before quantification using tandem mass-spectroscopy (MS/MS).
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.
Reverse-phase HPLC is the usual method and gives a percentage purity value. Mass spectrometry then confirms the molecular mass. Together they provide a basic identity and purity profile for a lot.