ACTH(4-10) raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2026-08-01. Anything still debated is marked as such rather than presented as settled.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It corresponds to the ACTH(4-7) fragment extended at the C-terminus by a Pro-Gly-Pro tripeptide, an addition intended to slow enzymatic breakdown. The molecular formula is C37H51N9O10S and the molecular mass is approximately 814 daltons. In the literature it is often described as an ACTH(4-10) analog, although that label reflects a naming convention as much as a precise structural relationship. The compound was developed in Russia and remains most closely associated with that research tradition.
Laboratory descriptions of the material are consistent across suppliers. It appears as a white to off-white lyophilized powder that dissolves readily in water and in polar organic solvents such as dimethyl sulfoxide. Aqueous solutions are clear and colorless at low concentrations. Because the peptide contains methionine, oxidation at the sulfur atom is a recognized degradation pathway, and handling notes usually call for protected, desiccated storage. Reported purity for research-grade lots is generally above 95 percent as measured by reversed-phase high-performance liquid chromatography.
The compound is registered in Russia as a pharmaceutical product, most commonly formulated as a nasal solution, and has been used in that setting since the 1990s. Outside that jurisdiction it is generally handled as a research chemical rather than an approved medicine. Regulatory status therefore differs sharply between countries, and material sold internationally may not correspond to the Russian pharmaceutical formulation. Documentation with commercial samples is typically limited to a certificate of analysis covering purity and identity, not clinical status or local legal classification.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Contains one methionine sulfur atom |
| Molecular mass | Approximately 814 Da | Consistent with a seven-residue peptide |
| Appearance | White to off-white powder | Typical lyophilized form |
| Solubility | Freely soluble in water | Also soluble in dimethyl sulfoxide |
| Typical storage | -20 °C, desiccated | Limits methionine oxidation |
Scientific literature on semax is unevenly distributed. A substantial share of published work originates from a small number of laboratories in Russia, while independent replication elsewhere is limited. Human data consist mostly of small trials with short follow-up, and several reported outcomes rely on subjective rating scales. Questions about how much intact peptide reaches the central nervous system after nasal administration, and how long it persists there, are still unresolved. The compound is best described as an active research subject rather than a settled pharmacological agent.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It was derived from the ACTH(4-10) fragment, a short segment of adrenocorticotropic hormone that lacks the hormonal activity associated with the full-length peptide. Researchers at the Institute of Molecular Genetics in Moscow developed the compound during the 1980s. It has been registered as a pharmaceutical product in Russia and several neighbouring countries, where it is supplied as a nasal solution, and it is also sold internationally as a research chemical.
The proposed mechanism centres on neurotrophic signalling rather than direct receptor activation. Semax is reported to increase expression of brain-derived neurotrophic factor and nerve growth factor in several brain regions, and to shift the balance between excitatory and inhibitory neurotransmitter systems. Interaction with melanocortin receptors has been suggested because of the parent ACTH fragment. Many of these findings come from rodent studies, and the extent to which they translate to human physiology remains an open question.
常规纯度与身份确认依赖反相高效液相色谱，并辅以质谱测定分子量。氨基酸组成分析可用于验证序列构成，肽图分析则能进一步定位修饰或降解产物。杂质谱通常关注缺失序列肽、截短片段和氧化产物。不同方法的检出限并不相同，因此各实验室报告的纯度数值不宜直接横向比较。
多数实验室与市售的 Semax 以冻干粉形式提供。冻干粉通常建议保存在 -20 °C 或更低温度下，同时避免光照与反复升温。短期运输有时采用冷藏条件，但长期保存仍以冷冻为主。分包操作应尽量减少开盖次数，以降低吸湿和微生物污染的风险。开封后若未一次用完，建议在干燥环境中密封并尽快放回低温储存。
Once the apples are gathered from trees in orchards they are scratted (ground down) into a pulp. Historically this was done using pressing stones with circular troughs, or by a cider mill. Cider mills were traditionally driven by the hand, water-mill, or horse-power. In modern times, they are likely to be powered by electricity. The pulp is then transferred to a cider press where the juice is extracted. Traditionally, the method for squeezing the juice from the apple pulp involves placing sweet straw or haircloths between stacked layers of apple pulp. Today, apples can be quickly pressed on a mechanised belt press. The juice, after being strained in a coarse hair-sieve, is then put into either open vats or closed casks. The remaining solids (pomace) are given to farm animals as winter feed, composted, discarded or used to make liqueurs.
==== Other activities ==== Bicalutamide has been found to act as an inhibitor or inducer of certain cytochrome P450 enzymes including CYP3A4, CYP2C9, CYP2C19, and CYP2D6 in preclinical research, but no evidence of this has been found in humans treated with up to 150 mg/day. It has also been identified in vitro as a strong inhibitor of CYP27A1 (cholesterol 27-hydroxylase) and as an inhibitor of CYP46A1 (cholesterol 24-hydroxylase), but this has yet to be assessed or confirmed in vivo or in humans and the clinical significance remains unknown. Bicalutamide has been found to be a P-glycoprotein (ABCB1) inhibitor. Like other first-generation NSAAs and enzalutamide, it has been found to act as a weak non-competitive inhibitor of GABAA receptor-mediated currents in vitro (IC50 = 5.2 μM). However, unlike enzalutamide, bicalutamide has not been found to be associated with seizures or other related adverse central effects, so the clinical relevance of this finding is uncertain.
=== Specialized reactions === As with all carbonyl compounds, the protons on the α-carbon are labile due to keto–enol tautomerization. Thus, the α-carbon is easily halogenated in the Hell–Volhard–Zelinsky halogenation. The Schmidt reaction converts carboxylic acids to amines. Carboxylic acids are decarboxylated in the Hunsdiecker reaction. The Dakin–West reaction converts an amino acid to the corresponding amino ketone. In the Barbier–Wieland degradation, a carboxylic acid on an aliphatic chain having a simple methylene bridge at the alpha position can have the chain shortened by one carbon. The inverse procedure is the Arndt–Eistert synthesis, where an acid is converted into acyl halide, which is then reacted with diazomethane to give one additional methylene in the aliphatic chain. Many acids undergo oxidative decarboxylation. Enzymes that catalyze these reactions are known as carboxylases (EC 6.4.1) and decarboxylases (EC 4.1.1). Carboxylic acids are reduced to aldehydes via the ester and DIBAL, via the acid chloride in the Rosenmund reduction and via the thioester in the Fukuyama reduction. In ketonic decarboxylation carboxylic acids are converted to ketones. Organolithium reagents (>2 equiv) react with carboxylic acids to give a dilithium 1,1-diolate, a stable tetrahedral intermediate which decomposes to give a ketone upon acidic workup. The Kolbe electrolysis is an electrolytic, decarboxylative dimerization reaction. It gets rid of the carboxyl groups of two acid molecules, and joins the remaining fragments together.
From 15 to 20 February, the Battle of Wadi al-Batin took place inside Iraq; this was the first of two attacks by 1 Battalion 5th Cavalry of the 1st Cavalry Division. It was a feint attack, designed to make the Iraqis think that a coalition invasion would take place from the south. The Iraqis fiercely resisted, and the Americans eventually withdrew as planned back into the Wadi al-Batin. Three US soldiers were killed and nine wounded, with one M2 Bradley IFV turret destroyed, but they had taken 40 prisoners and destroyed five tanks, and successfully deceived the Iraqis. This attack led the way for the XVIII Airborne Corps to sweep around behind the 1st Cav and attack Iraqi forces to the west. On 22 February 1991, Iraq agreed to a Soviet-proposed ceasefire agreement. The agreement called for Iraq to withdraw troops to pre-invasion positions within six weeks following a total ceasefire, and called for monitoring of the ceasefire and withdrawal to be overseen by the UN Security Council. The coalition rejected the proposal, but said that retreating Iraqi forces would not be attacked, and gave 24 hours for Iraq to withdraw its forces. On 23 February, fighting resulted in the capture of 500 Iraqi soldiers. On 24 February, British and American armored forces crossed the Iraq–Kuwait border and entered Iraq in large numbers, taking hundreds of prisoners. Iraqi resistance was light, and four Americans were killed.
Sources: en.wikipedia.org
Exclusive breastfeeding usually delays the return of fertility through lactational amenorrhea, although it does not provide reliable birth control. Mothers may not ovulate or have regular periods during the entire lactation period. The non-ovulating period varies by individual. This has been used as natural contraception, with greater than 98% effectiveness during the first six months after birth if specific nursing behaviors are followed.
It is a serious matter if you can just create things that are not right." Arsenal's press officer Clare Tomlinson, who was present at the news conference, recalled Wenger phoning the next day and demanding why he could not take action against the press for printing the story. The culprit responsible for spreading gossip in the City later apologised to Wenger. During this, Arsenal had led the Premier League, but poor form in February 1997 caused Wenger to rule out his team's chances of winning the title. They finished third in his first season, missing out on UEFA Champions League qualification to Newcastle United on goal difference – the tiebreaker used to determine the ranking between teams equal on points.
US-India ties began to strain in April 2021 when India faced a massive spike in COVID-19 infections. The US had invoked the Defense Production Act of 1950 to ban the export of raw materials needed to produce vaccines in order to prioritize domestic vaccine production. According to The Times of India, this also caused an explosion of anti-US sentiment in India, as the U.S. had vaccine reserves and refused to share COVID-19 vaccine patents. This came after a plea by Adar Poonawalla, CEO of the Serum Institute of India, to lift the embargo on export of raw materials needed to ramp up production of COVID-19 vaccines, was rejected. However, in late April, right after a phone call with Ajit Doval, the National Security Advisor of India, the Biden administration stated it would make raw materials necessary for production of the Oxford–AstraZeneca COVID-19 vaccine available to India, and began to send more than ₹714 crore (equivalent to ₹874 crore or US$91 million in 2026) worth of drug treatments, rapid diagnostic tests, ventilators, personal protective equipment, and mechanical parts needed to manufacture vaccines to India, along with a team of public health experts from the United States Centers for Disease Control and Prevention. The US also stated that it planned to finance the expansion of Biological E. Limited, an Indian-based COVID-19 vaccine production company. India entered negotiations with the US after it declared that it would share 60 million Oxford-AstraZeneca vaccines with the world.
Anemia Insufficient red cell mass (anemia) can be the result of bleeding, blood disorders like thalassemia, or nutritional deficiencies, and may require one or more blood transfusions. Anemia can also be due to a genetic disorder in which the red blood cells do not function effectively. Anemia can be confirmed by a blood test if the hemoglobin value is less than 13.5 gm/dl in men or less than 12.0 gm/dl in women. Several countries have blood banks to fill the demand for transfusable blood. A person receiving a blood transfusion must have a blood type compatible with that of the donor. Sickle-cell anemia Disorders of cell proliferation Leukemia is a group of cancers of the blood-forming tissues and cells. Non-cancerous overproduction of red cells (polycythemia vera) or platelets (essential thrombocytosis) may be premalignant. Myelodysplastic syndromes involve ineffective production of one or more cell lines. Disorders of coagulation Hemophilia is a genetic illness that causes dysfunction in one of the blood's clotting mechanisms. This can allow otherwise inconsequential wounds to be life-threatening, but more commonly results in hemarthrosis, or bleeding into joint spaces, which can be crippling. Ineffective or insufficient platelets can also result in coagulopathy (bleeding disorders). Hypercoagulable state (thrombophilia) results from defects in regulation of platelet or clotting factor function, and can cause thrombosis. Infectious disorders of blood Blood is an important vector of infection.
Multiple stages of mass analysis separation can be accomplished with individual mass spectrometer elements separated in space or using a single mass spectrometer with the MS steps separated in time. For tandem mass spectrometry in space, the different elements are often noted in a shorthand, giving the type of mass selector used.
Sources: en.wikipedia.org
The talks concluded on 12 April 2026. The negotiations lasted about 21 hours and ended with the United States and Iranian delegations leaving Islamabad without reaching a deal. The main unresolved issues reportedly included Iran's nuclear program and the status of the Strait of Hormuz. Other issues included sanctions relief and frozen assets. While the US side insisted on a phased relief linked to compliance, Iran demanded comprehensive lifting of sanctions and release of assets, including $6 billion in frozen assets, as a precondition to a meaningful deal. Iranian officials said they had not expected an agreement to be reached in a single round of talks and that contacts were expected to continue. Pakistani officials described the talks as part of an effort to preserve the ceasefire and encourage further diplomacy between the parties. Iran's minister of foreign affairs Abbas Araghchi claimed that they were "inches away from an MoU" and accused the US delegation of moving the goalposts and maximalizing. More broadly, the Iranian delegation believed that Washington had to do more to earn their trust. According to an analysis in Iran International, Iran's diplomacy following the failure of the talks has been to express defiance towards American pressure while leaving the possibility of future diplomacy still open. Trump claimed that Iran had "knowingly failed" to reopen the Strait of Hormuz, and Vance said that Iran had refused the possibility of not developing nuclear weapons.
=== Switzerland === In Switzerland, the equivalent profession to a clinical biologist is the FAMH Specialist in Laboratory Medicine. This title is awarded by the Foederatio Analyticorum Medicinalium Helveticorum (FAMH), the Swiss organization responsible for the postgraduate training and certification of specialists in medical laboratory diagnostics. To obtain this title, professionals must complete a four-year postgraduate training program, which is carried out alongside employment in an accredited medical laboratory. The program is open to individuals holding a medical degree (MD), a pharmacy degree, or a master’s/PhD in biomedical sciences, biology, or related disciplines. The training covers several specialties, including hematology, clinical chemistry, medical microbiology, immunology, and genetics. The FAMH Specialist in Laboratory Medicine plays a key role in medical diagnostics. They are responsible for the supervision and interpretation of laboratory analyses, validation of results, and communication with clinicians. They also ensure quality management and compliance with ISO 15189 standards, while contributing to the training and supervision of laboratory technical staff. The FAMH Specialist title is federally recognized and is a mandatory requirement to lead and validate medical diagnostic laboratories in Switzerland.
Butorphanol is a morphinan-type synthetic agonist–antagonist opioid analgesic developed by Bristol-Myers. Butorphanol is most closely structurally related to levorphanol. Butorphanol is available as the tartrate salt in injectable, tablet, and intranasal spray formulations. The tablet form is only used in dogs, cats and horses due to low bioavailability in humans. It was patented in 1971 and approved for medical use in 1979.
=== Elimination === Testosterone and its metabolites are eliminated in urine. It is excreted mainly as androsterone glucuronide and etiocholanolone glucuronide. It is also excreted to a small extent as other conjugates such as testosterone glucuronide (1%), testosterone sulfate (0.03%), and androstanediol glucuronides. Only a very small amount of testosterone (less than 0.01%) is found unchanged in the urine.
Hazard research is published: a study finds the likelihood of receiving a dementia diagnosis varies 2-fold based on place of residence in the U.S. after adjusting for underlying sociodemographic and population dementia risk factors, indicating there to be further regional risk factors or especially worse diagnostics (16 Aug.), and a study shows of the infant and toddler foods in 10 major grocery chains, 60% failed to meet the nutritional requirements of the WHO's nutrient and promotion profile model (NPPM) (21 Aug.).
Sources: en.wikipedia.org
It is registered as a pharmaceutical product in Russia, where it is typically supplied as a nasal solution. In most other countries it is not an approved drug and is traded as a research chemical instead. Approval status depends entirely on the jurisdiction involved.
Most published work uses intranasal administration, matching the route of the registered Russian formulation. Some animal experiments use intravenous or intraperitoneal injection. The route matters because the intact peptide is cleared rapidly from blood, so exposure differs between methods.
A purity value describes the share of the powder accounted for by the target peptide, usually by high-performance liquid chromatography. It does not confirm that the sequence is correct, which requires mass spectrometry or amino acid analysis. Purity and identity are separate checks.
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.