This is a working overview of melanocortin signalling, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-08-01 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.
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.
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.
| 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 |
Clinical reports describe use in ischaemic stroke, transient ischaemic attack, optic nerve conditions, and cognitive complaints, but most of these studies are small and were conducted in a single region. Systematic reviews have generally described the evidence base as limited in size and variable in methodological quality. Randomised controlled data suitable for international regulatory assessment are scarce. As a result, major treatment guidelines outside Russia do not include the peptide, and interest in it remains largely research-driven rather than routine clinical.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It is described in the literature as an analogue of the ACTH(4–10) fragment, a short N-terminal portion of adrenocorticotropic hormone that retains some neurotropic activity without the full hormonal effects of the parent peptide. The molecule carries a methionine residue at the N-terminus and two proline residues near the C-terminus, features that shape both its interactions with receptor systems and its chemical stability. The free peptide corresponds to the formula C37H51N9O10S and a molecular mass near 813.9 Da.
Stability depends heavily on physical state. Lyophilized powder held dry, cold and dark retains its content over long periods, whereas dissolved peptide begins to change within days at room temperature. The most cited degradation route is oxidation of the methionine residue, which converts the peptide to a sulfoxide form that elutes differently on chromatography. Hydrolysis of amide bonds and adsorption onto container walls contribute smaller losses. Buffers that exclude oxygen from the headspace slow the oxidation pathway, but no single condition prevents all change indefinitely.
Practical handling follows from those properties. Bulk material is best divided into single-use portions soon after receipt, because each thaw exposes the whole container to moisture and temperature cycling. Vials should be allowed to reach room temperature before opening to prevent condensation on the powder. Low-binding plasticware reduces loss of dilute solutions, and sterile filtration is used when a preparation must remain free of microbial growth. Records of batch number, reconstitution date and storage history are what allow a later analytical result to be interpreted meaningfully.
Semax 是一种人工合成的七肽，氨基酸序列为 Met-Glu-His-Phe-Pro-Gly-Pro，单字母缩写记作 MEHFPGP。它被归类为促肾上腺皮质激素片段 ACTH(4-10) 的结构类似物，但并不天然存在于生物体内。母体片段 ACTH(4-10) 的序列为 Met-Glu-His-Phe-Arg-Trp-Gly，Semax 替换了中间两个残基，并在羧基端延长了 Pro-Gly-Pro 三肽。这种延长被普遍认为能提升分子对肽酶的耐受性。
该化合物于二十世纪八十年代在俄罗斯被开发，相关工作由俄罗斯科学院分子遗传学研究所的研究团队主导。开发目标并非复制 ACTH 的完整激素活性，而是寻找保留其神经作用方向、同时去除促肾上腺皮质激素释放效应的短肽片段。研究记录显示，这一方向促成了多个相关短肽的合成与筛选，而 Semax 是其中被研究最广泛的一个。当地文献常以 Семакс 这一名称指代它。
研究兴趣主要集中在神经营养因子相关的路径上，包括脑源性神经营养因子与神经生长因子的表达变化。部分实验报告称在特定条件下观察到这些因子的水平上升，但具体信号通路和剂量依赖关系仍未完全厘清。多数公开数据来自细胞模型和动物实验，人体对照研究数量有限。因此，该化合物的作用机制在文献中属于活跃讨论，而非已经确立的定论。
Semax is normally supplied as a lyophilized powder, and that form is the most stable. Suppliers commonly recommend storage at -20 °C in a desiccated container protected from light, with short-term handling at room temperature limited to weighing and transfer. Powder that has absorbed moisture degrades faster, so vials should be warmed to ambient temperature before opening to prevent condensation on the contents. Hygroscopic behavior is typical of short hydrophilic peptides, and humidity control matters more than temperature alone for long-term retention.
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.
When signs of tolerance to midazolam occur during intensive care unit sedation the addition of an opioid or propofol is recommended. Withdrawal symptoms can include irritability, abnormal reflexes, tremors, clonus, hypertonicity, delirium and seizures, nausea, vomiting, diarrhea, tachycardia, hypertension, and tachypnea.
=== Type 1 diabetes === Insulin degludec was studied as an alternative to insulin glargine as part of a basal-bolus regimen in the BEGIN Basal-Bolus Type 1 trial. 629 participants with type 1 diabetes were randomized in a 3:1 ratio to either insulin degludec (n=472) or insulin glargine (n=157) in addition to mealtime insulin aspart. Participants in the degludec treatment arm were switched from their basal insulin to insulin degludec in a 1:1 ratio, with a 20-30% dose reduction in participants receiving multiple basal doses per day. After 52 weeks, participants treated with insulin degludec produced a similar reduction in HbA1c (0.40% vs. 0.39%) meeting the criteria for noninferiority. Adverse events were similar in the two treatment arms; however, rates of nocturnal hypoglycemia (between midnight and 6am) were 27% lower in participants treated with insulin degludec (3.91 vs. 5.22 episodes per patient-year of exposure, p=0.024). The reduction in the incidence of hypoglycemia was seen as a therapeutic benefit, as hypoglycemia is often a dose limiting toxicity in insulin therapy. A systematic review has compared the use of insulin degludec to that of insulin glargine, insulin detemir and NPH insulin in adults and children diagnosed with type 1 diabetes. This review included Randomized Control Trials (RCTs) with a duration of 24 to 104 weeks and had a total sample of 8784 participants randomized across studies: 2428 participants allocated to NPH insulin; 2889 participants to insulin detemir; 2095 participants to insulin glargine; 1372 participants to insulin degludec.
In July 2009, Sovershenno Sekretno wrote that before the war, the hospital was deployed near South Ossetia while smaller group of military doctors were deployed to Abkhazia and asked "does it mean that intensive hostilities were not planned there [in Abkhazia]?" The newspaper noted that General Alexey Maslov was fired from the post of Commander-in-Chief of the Russian Ground Forces several days before the full-scale invasion of Georgia and some changes were related to the preparation of the war against Georgia. It quoted an unnamed Russian General Staff member as having said that "Some prepared the operation, while others came to sit on the ready laurels". The newspaper also wrote that the Russian Air Force was covering up the loss of one Sukhoi Su-24. The newspaper concluded that Russia needed South Ossetia as bridgehead for offensive operations. In November 2011, Stanislav Sadalsky commented on Medvedev's statement to have halted NATO expansion in 2008 that this was an admission that it was Medevedev who started the war, which was prosecutable under the Criminal Code of Russia.
Sources: en.wikipedia.org
==== Intramuscular or subcutaneous ==== Naloxone can also be administered via intramuscular or subcutaneous injection. The onset of naloxone provided through this route is 2 to 5 minutes with a duration of around 30–120min. Naloxone administered intramuscularly are provided through pre-filled syringes, vials, and auto-injector. A hand-held auto-injector is pocket-sized and can be used in non-medical settings such as in the home. It is designed for use by laypersons, including family members and caregivers of opioid users at risk for an opioid emergency, such as an overdose. According to the FDA's National Drug Code Directory, a generic version of the auto-injector began to be marketed at the end of 2019.
== Side effects and label warnings == The most common side effects are nausea, fatigue, vomiting, alopecia (hair loss), constipation, decreased appetite, anemia (hemoglobin in blood is below the reference range), decreased neutrophil count (white blood cells that help lead the body's immune system response to fight infection), diarrhea, leukopenia (other white blood cells that help the immune system), cough and decreased platelet count (component of blood whose function is to react to bleeding from blood vessel injury by clumping, thereby initiating a blood clot). The prescribing information for trastuzumab deruxtecan includes a boxed warning about the risk of interstitial lung disease (a group of lung conditions that causes scarring of lung tissues) and embryo-fetal toxicity. Interstitial lung disease and pneumonitis, including cases resulting in death, have been reported with trastuzumab deruxtecan.
== Advantages and disadvantages == BV provides a good measure of the usability of proteins in a diet and also plays a valuable role in detection of some metabolic diseases. BV is, however, a scientific variable determined under very strict and unnatural conditions. It is not a test designed to evaluate the usability of proteins whilst an organism is in everyday life — indeed the BV of a diet will vary greatly depending on age, weight, health, sex, recent diet, current metabolism, etc. of the organism. In addition BV of the same food varies significantly species to species. Given these limitations BV is still relevant to everyday diet to some extent. No matter the individual or their conditions a protein source with high BV, such as egg, will always be more easily used than a protein source with low BV.
Sources: en.wikipedia.org
Surface magnetic resonance (or magnetic resonance sounding) is based on the principle of nuclear magnetic resonance (NMR) and measurements can be used to indirectly estimate the water content of saturated and unsaturated zones in the earth's subsurface. SNMR is used to estimate aquifer properties, including quantity of water contained in the aquifer, porosity, and hydraulic conductivity.
Sanders expresses her disappointment in the fact that even if they are able to find a diagnosis or treatment for his illness, he may not be able to recover all the memories he has already lost. From the hundreds of responses Dr. Sanders highlighted 2 very interesting possibilities one caused by a virus and the other caused by an autoimmune disorder. The first possibility is Progressive Multifocal Leukoencephalopathy that is caused by a virus and destroys the brain's ability to translate information. The second possibility is a very rare autoimmune disease by the name of Neuro-Behcet’s that causes inflammation and ulceration in different types of the body. Neither of these diagnoses seemed to fit Willie exactly because of key features such as Willie’s very strong immune system and the fact that he had no response to steroids. Due to Willie’s background in the Army, the suggestion of the Gulf War Illness was brought up. When Dr. Sanders brought this idea to another physician for a second diagnosis, they highlighted key similarities between Willie's condition and the Gulf War Illness despite his being much more severe. The idea of the Gulf War Illness was tossed around as a possibility and brought up to many physicians for second opinions, each one highlighting his symptoms are much more severe, and suggesting the possibility of testing for further clarity. To better understand the chances of Willie having the Gulf War Illness, they need to know if he was exposed to the toxins present during the Gulf War.
On 16 March, Pakistan said that its forces launched multiple airstrikes against Taliban military installations in Kabul and Nangarhar, and claimed that it destroyed ammo storages and "technical support infrastructure". Taliban claimed that Pakistani strikes on Khost province killed four civilians and wounded nine, and destroyed civilian infrastructure in Kunar and Paktika province with 43 rounds being fired into Shkin district. A militant attack on a police post in Bannu District was repulsed by police forces. Following the strikes, Afghanistan claimed that a Pakistani airstrike struck the Omid Addiction Treatment Hospital in Kabul, reportedly killing over 200 people, mostly drug addicts undergoing treatment at the drug rehabilitation facility. Pakistan denied the claims and said that it had only targeted Taliban military installations. While the health ministry spokesperson maintained that there were "more than 200 martyrs and more than 200 injured," deputy government spokesperson Hamdullah Fitrat claimed death toll was at least "double" that, with 250 wounded. Zabihullah Mujahid declared it a "crime against humanity". On 17 March, five Pakistani soldiers were killed and three wounded in a skirmish at Ghulam Khan border crossing in North Waziristan District. A militant attack in Badaber injured two policemen. On 18 March, Pakistani missile strikes in Asadabad wounded six civilians. According to Taliban, Pakistan conducted 63 missile strikes on Nari District, 33 on Manogai, 13 on Sarkani, six on Shultan and six on Asadabad.
While in Constantine's treatise Liber de Coitu, the clitoris is referred to a few times, Magnus gave an equal amount of attention to male and female organs. Like Avicenna, Magnus also used the word virga for the clitoris, but employed it for the male and female genitals; despite his efforts to give equal ground to the clitoris, the cycle of suppression and rediscovery of the organ continued, and a 16th-century justification for clitoridectomy appears to have been confused with intersex conditions and the imprecision created by the word nymphae substituted for the word clitoris. Nymphotomy was a medical operation to excise an unusually large clitoris, but what was considered "unusually large" was often a matter of perception. The procedure was routinely performed on Egyptian women, due to physicians such as Jacques Daléchamps who believed that this version of the clitoris was "an unusual feature that occurred in almost all Egyptian women [and] some of ours, so that when they find themselves in the company of other women, or their clothes rub them while they walk or their husbands wish to approach them, it erects like a male penis and indeed they use it to play with other women, as their husbands would do ... Thus the parts are cut".
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.
Reversed-phase high-performance liquid chromatography is the standard method, with detection in the ultraviolet range. Peak area percentage yields a purity figure for the main component. Mass spectrometry is normally run alongside to confirm molecular identity.