The short version of Semax fits in a sentence. The long version — which is the one that helps — is below.
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Published studies examine a fairly narrow set of endpoints. Rodent experiments commonly measure maze learning, infarct volume after induced ischemia, and tissue levels of neurotrophic factors. Clinical reports from Russian centres describe attention, memory and recovery scores in patients after stroke or transient ischemic attack. Most of those human studies are small and few have been repeated by independent groups. Outcome measures differ between studies, which limits direct comparison.
Circulation time for the peptide is short because peptidases cleave it readily. The Pro-Gly-Pro tail is thought to slow breakdown compared with the bare ACTH fragment, but the gain appears modest. Absorption after intranasal dosing is limited, and only a fraction of a dose is expected to reach the central nervous system. Laboratory concentrations therefore sit well above levels achieved systemically, a gap that complicates translation from bench findings to clinical claims.
Semax is a synthetic heptapeptide whose sequence is Met-Glu-His-Phe-Pro-Gly-Pro. The first four residues correspond to the ACTH(4-10) fragment, while the terminal Pro-Gly-Pro extension was added to improve metabolic stability. Its molecular formula is C37H51N9O10S and its monoisotopic mass is approximately 813.9 Da. The compound is classified as a peptide research chemical and as a registered pharmaceutical product in Russia, but it does not hold marketing approval in the European Union or the United States. Naming conventions vary across supplier catalogs.
Development of the compound took place in the Soviet Union during the 1980s, largely through peptide research groups affiliated with the Shemyakin-Ovchinnikov Institute and Moscow State University. Investigators screened fragments of adrenocorticotropic hormone for activity on the central nervous system while attempting to separate cognitive effects from hormonal ones. The shortened sequence was selected because it retained behavioral activity in animal models without stimulating corticosteroid release. Early publications described the molecule as an ACTH(4-10) analog.
| Property | Value | Notes |
|---|---|---|
| Appearance | White to off-white powder | Lyophilized solid from research suppliers |
| Solubility | Freely soluble in water | Also dissolves in aqueous buffers; solutions are used fresh |
| Typical storage temperature | -20 °C for lyophilized powder | Short-term transport at 2-8 °C is common |
| Common analytical method | Reverse-phase HPLC | Paired with mass spectrometry for identity confirmation |
| Common synonyms | ACTH(4-10) analogue; MEHFPGP | N-terminal methionine retained in the chain |
Quality documentation for research-grade peptide usually includes a certificate of analysis stating purity, identity, and residual counterion content. Batch-to-batch variation in purity and salt form is a recognized issue, and comparisons across suppliers require attention to the exact counterion, for example acetate versus trifluoroacetate. Sequence verification by tandem mass spectrometry provides stronger evidence than a single mass measurement. For any study reporting biological results, the analytical method and the measured purity should be stated explicitly. Independent verification of supplier claims is considered good practice.
Semax is supplied as a lyophilized powder that appears white to off-white. It dissolves readily in water, phosphate-buffered saline, and other aqueous media, which simplifies preparation of working solutions for laboratory use. The nasal products registered in Russia are dilute aqueous solutions, typically around 0.1 percent peptide by weight. Organic solvents are rarely necessary and can complicate handling. Because the peptide is hygroscopic, weighing should be performed quickly and with minimal exposure to ambient humidity.
Solid material is normally kept at minus 20 degrees Celsius in a sealed, desiccated container. Reconstituted solutions are less stable and are usually divided into single-use aliquots before freezing. Repeated freeze-thaw cycles are avoided because they promote aggregation and loss of activity. Light exposure is minimized by using amber glassware or foil wrapping. Published stability data for this peptide are sparse, so recommended storage conditions rest mainly on general practice for short synthetic peptides rather than on dedicated study.
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.
Later generations of the molecule include an N-acetylated form and an amidated form, both marketed online alongside the parent peptide. These variants differ in terminal chemistry and stability, and they are frequently discussed in the same breath even though they have not been compared in controlled trials. Supply outside formal healthcare systems comes largely from laboratories that synthesize peptides to order. Purity and identity of these materials vary widely, and no single body oversees the international trade.
溶液状态的稳定性明显低于冻干粉。肽类在水溶液中可能经历水解、氧化与聚集，其中甲硫氨酸和天冬酰胺等残基常是敏感位点。Semax 含有甲硫氨酸，因此氧化风险相对突出。工作液一般主张现配现用，或冷藏并在数日内用尽。缓冲液种类、pH 和离子强度都会影响降解速率，而关于最佳条件的公开数据并不统一。
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。
World Refrigeration Day is an international day established by the World Refrigeration Day Secretariat in Derbyshire, England. Held annually on 26 June, it was created to raise awareness about the importance of refrigeration technologies in everyday life and to raise the profile of the refrigeration, air-conditioning and heat-pump sector. The day was chosen to celebrate the birth date of Lord Kelvin on 26 June 1824.
=== Fetus earrings === During the 1984 exhibition of freeze-dried sculptures in London, Gibson was given two dehydrated human fetuses from an anatomy professor. They were 10 weeks in development and had been dehydrated for 20 years. Gibson re-hydrated both fetuses, freeze-dried them and attached them as earrings to a female mannequin head. The sculpture was titled Human Earrings. They were exhibited at the Young Unknowns Gallery in south London in December 1987. On Thursday, 3 December 1987, the sculpture was seized by the Metropolitan Police. Because of this incident, Gibson was expelled from Goldsmiths College on 21 December 1987, where he was studying post-graduate art, design and technology. On 11 April 1988, Gibson and the gallery owner, Peter Sylveire, were formally charged with the common law offences of exhibiting a public nuisance and outraging public decency. The trial started on Monday, 30 January 1989 at the Old Bailey in central London. The judge was Brian Smedley, Michael Worsley was the prosecuting barrister, and Geoffrey Robertson and Helena Kennedy were the defence barristers. On 6 February 1989, the charge of public nuisance was dismissed. On Tuesday, 9 February 1989, the jury of 10 women and 2 men found Gibson and Sylveire guilty of outraging public decency. Gibson was fined £500 and Sylveire was fined £300. Immediately following the verdict, an appeal application was filed. However, on 10 July 1990, the Court of Appeal dismissed the case and upheld the earlier conviction.
A visa is a travel document issued to foreign nationals enabling them to clear border controls. They traditionally take the form of an adhesive sticker or, occasionally, a stamp affixed to a page in an individual's passport or equivalent document. Visas policies different purposes depending on the priorities of each jurisdiction, ranging from ensuring that visitors do not pose a national security risk or have sufficient financial resources to simply functioning as a tax on tourists, as is the case with countries like Mauritius and other leisure destinations which issue visas on arrival, electronic visas, or electronic travel authorisations (ETAs) to most or all visitors. Visas may include limits on the duration of the foreigner's stay, areas within the state they may enter, the dates they may enter, the number of permitted visits, or an individual's right to work in the state in question. Many countries in Asia have liberalised their visa controls in recent years to encourage transnational business and tourism. For example, India, Myanmar, and Sri Lanka have introduced electronic visas to ease border control for business travellers and tourists. Malaysia has introduced similar eVisa facilities and the eNTRI programme to expedite clearance for Indian and mainland Chinese citizens. Thailand regularly issues visas on arrival to many non-exempt visitors at major ports of entry to encourage tourism.
Sources: en.wikipedia.org
=== Subcellular localization === The c1orf27 protein is likely cytoplasmic. This was found with 55.5 reliability. The K-NN prediction was k = 9/23 and the protein was found to be 55.6% cytoplasmic, 11.1% mitochondrial, 11.1% vacuolar, 11.1% cytoskeletal, and 11.1% golgi.
==== Education ==== Even with the acceleration of the transmission of COVID-19 in the city and the increase in the occupation of beds at hospitals, Melo maintained the plan to recommence classes in municipal schools on 22 February 2021. He had only cancelled the beginning of the school year when the city had been put under the black flag category, the highest category for social distancing, due to a high risk of infections. A part of the municipal schools would return to opening at the beginning of May, even if some of the teachers had not been vaccinated, in contrast to what had been happening in neighboring cities such as Esteio and São Leopoldo. Days before, the teachers had called for protests against returning to in-person classes during the middle of the pandemic without vaccination.
=== Enzyme production === A significant milestone in the use of K. phaffii in food technology was its GRAS classification by the US Food and Drug Administration, alongside their approval of recombinant proteins. It is now used to produce various enzymes that serve as processing aids and food additives. In bakery production, enzymes produced by genetically modified Komagataella can maintain bread freshness and compensate for variations in flour and malt quality. In brewing, they can reduce beer's alcohol content or modify the flavour and filtration properties of wine. Recombinant expressed phospholipase C is used to degum high-phosphorus vegetable oils by hydrolysing phospholipids. In animal feed, phytase produced by K. phaffii breaks down phytic acid, an antinutrient. Recently, K. phaffii has been used increasingly to produce soy leghemoglobin, a plant heme protein that gives plant-based meat analogues their colour and flavour. This expands the industrial application of K. phaffii from technical enzymes towards functional food ingredients. For this purpose, the yeast utilises its strong methanol-inducible promoters and efficient secretion to produce functional leghemoglobin for use as a food ingredient. Through strain engineering, including optimisation of heme biosynthesis and signal peptides, and controlled fed-batch fermentation, gram-per-litre titres of secreted leghemoglobin have been achieved. This makes large-scale production for meat analogues economically viable.
Ketones in the urine or blood, as detected by urine strips or a blood ketone testing meter, may indicate the beginning of diabetic ketoacidosis (DKA), a dangerous and often quickly fatal condition caused by high glucose levels (hyperglycemia) and low insulin levels combined with certain other systemic stresses. DKA can be arrested if caught quickly. Ketones are produced by the liver as part of fat metabolism and are normally not found in sufficient quantity to be measured in the urine or blood of non-diabetics or well-controlled diabetics. The body normally uses glucose as its fuel and is able to do so with sufficient insulin levels. When glucose is not available as an energy source because of untreated or poorly treated diabetes and some other unrelated medical conditions, it begins to use fat for energy instead. The result of the body turning to using fat instead of glucose for energy means ketone production that is measurable when testing either urine or blood for them. Ketone problems that are more serious than the "trace or slight" range need immediate medical attention; they cannot be treated at home. Veterinary care for ketosis/ketoacidosis can involve intravenous (IV) fluids to counter dehydration, when necessary, to replace depleted electrolytes, intravenous or intramuscular short-acting insulin to lower blood glucose levels, and measured amounts of glucose or force feeding, to bring the metabolism back to using glucose instead of fat as its source of energy.
Sources: en.wikipedia.org
The first human to human heart transplantation was performed in 1967 by the South African surgeon Christiaan Barnard at Groote Schuur Hospital in Cape Town. This marked an important milestone in cardiac surgery, capturing the attention of both the medical profession and the world at large. However, long-term survival rates of patients were initially very low. Louis Washkansky, the first recipient of a donated heart, died 18 days after the operation while other patients did not survive for more than a few weeks. The American surgeon Norman Shumway has been credited for his efforts to improve transplantation techniques, along with pioneers Richard Lower, Vladimir Demikhov and Adrian Kantrowitz. By mid-2018, the International Society for Heart and Lung Transplantation registry had recorded more than 146,000 heart transplantations worldwide. The first successful transplant of a heart from a genetically modified pig to a human was performed on 7 January 2022 in Baltimore by heart surgeon Bartley P. Griffith. The recipient, 57-year-old David Bennett, survived for 60 days before dying on 8 March 2022. By the middle of the 20th century, heart disease had surpassed infectious disease as the leading cause of death in the United States, and it is currently the leading cause of deaths worldwide. Since 1948, the ongoing Framingham Heart Study has shed light on the effects of various influences on the heart, including diet, exercise, and common medications such as aspirin.
=== Shear stress === Shear stress is another variable used in erosion and sediment transport models representing the force applied on a surface by a perpendicular force, and can be calculated using the following formula
=== Cultivation === The saffron crocus, unknown in the wild, probably descends from Crocus cartwrightianus. It is a triploid that is "self-incompatible" and male sterile; it undergoes aberrant meiosis and is hence incapable of independent sexual reproduction—all propagation is by vegetative multiplication via manual "divide-and-set" of a starter clone or by interspecific hybridisation. Crocus sativus thrives in the Mediterranean maquis, an ecotype superficially resembling the North American chaparral, and similar climates where hot and dry summer breezes sweep semi-arid lands. It can nonetheless survive cold winters, tolerating frosts as low as −10 °C (14 °F) and short periods of snow cover. Some reports suggest saffron can tolerate an air temperature range from −22 to 40 °C. Irrigation is required if grown outside of moist environments such as Kashmir, where annual rainfall averages 1,000–1,500 mm (40–60 in); saffron-growing regions in Greece (500 mm or 20 in annually) and Spain (400 mm or 16 in) are far drier than the main cultivating Iranian regions. What makes this possible is the timing of the local wet seasons; generous spring rains and drier summers are optimal. Rain immediately preceding flowering boosts saffron yields; rainy or cold weather during flowering promotes disease and reduces yields. Persistently damp and hot conditions harm the crops, and rabbits, rats, and birds cause damage by digging up corms. Nematodes, leaf rusts, and corm rot pose other threats.
Sources: en.wikipedia.org
It consists mainly of animal experiments and small clinical reports, with much of the clinical material published in Russian-language journals. Large independent trials are scarce. Separating reliable effects from chance findings is consequently difficult.
A fraction of an intranasal dose is thought to reach the central nervous system, and this route is favoured partly for that reason. The proportion is not well characterized. Direct measurement in humans remains difficult with current methods.
Raised BDNF and NGF expression has been reported across several animal studies, which makes the signal fairly consistent. Whether the same change occurs in humans at usable doses is not established. It is best treated as a working hypothesis rather than a confirmed clinical mechanism.
It is a synthetic peptide of seven amino acids. Its backbone corresponds to a fragment of adrenocorticotropic hormone extended at the carboxyl end. The material is distributed as a lyophilized solid for laboratory use.