intranasal delivery raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2026-03-30. Anything still debated is marked as such rather than presented as settled.
The mechanisms attributed to semax are inferred from animal and cell studies rather than traced to one confirmed target. The most frequently cited pathway involves increased expression of brain-derived neurotrophic factor and nerve growth factor in hippocampal and cortical tissue. Some work points to engagement of melanocortin receptors, particularly MC4, which the parent ACTH fragment can activate. Effects on dopaminergic and serotonergic signalling have also been reported. No single account explains all observed results, and the relative weight of each pathway remains unsettled.
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.
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。
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。
| 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 |
Published research covers ischemic stroke, traumatic brain injury, cognitive impairment, optic nerve conditions and attention-related measures. Much of the human evidence comes from small trials conducted in one country, which limits how far the results generalize. Animal models supply the larger share of the data, and effects seen in rodents do not transfer automatically to people. Reviews have noted that methodological reporting is often incomplete, making it difficult to pool results or compare treatment schedules across studies.
Pharmacokinetic accounts emphasize rapid breakdown. After intravenous dosing the intact peptide disappears from blood within minutes, and nasal delivery produces low but measurable concentrations. Metabolites rather than the parent molecule may account for part of the observed activity, although the relative contribution is unresolved. Dosing in the literature varies widely and no optimal schedule has been agreed. These gaps are regularly cited as a reason the findings have not produced broad clinical adoption beyond the original research setting.
Identity and purity of Semax are established mainly by reversed-phase high-performance liquid chromatography coupled with mass spectrometry. The chromatographic trace gives a purity estimate as a percentage of total peak area, while electrospray or matrix-assisted laser desorption ionization confirms the molecular mass against the calculated value. Amino acid analysis and sequence-specific fragmentation provide further confirmation when a supplier's chain of custody is unclear. Vendors frequently quote a purity figure without stating the detection wavelength or the integration method, which limits how far one number can be compared with another.
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.
Attempts to contact by mail in the late 1890s failed. United Brothers of Friendship - Founded August 1, 1861, by young local students in day or night schools. In 1868, on the advice of their teacher, W.H. Gibson, the society reorganized. Many chapters were formed in Kentucky, and a statewide Grand Lodge was formed in 1871. After establishing chapters outside Kentucky a National Grand Lodge was formed. W.H. Gibson served as the first State Grand Master for five years and as National Grand Master for four years. Unofficial female auxiliaries were called the Sisters of Friendship until 1878 when the organization formed the official Sisters of the Mysterious Ten, organized in local Temples. In 1878 the Order had about 4,000 members. That was the year they decided to establish another auxiliary, the Knights of Friendship, based on the story of David and Jonathan. In 1892 the UBF had 100,000 members in 19 states and 2 territories with 30,000 in Missouri alone. It was known to be active in Kentucky, Missouri, Arkansas, Louisiana, Texas, Mississippi, Alabama, Tennessee, West Virginia, Virginia, the District of Columbia, Pennsylvania, New York, New Jersey, Michigan, Kansas, Colorado, Washington, Canada, the West Indies and Africa. While predominantly black, the order had white members. There was evidence that the Grand United Order of Odd Fellows had something to do with its founding. United Knights and Daughters of America - Headquartered in St. Louis, Missouri. Reportedly had many members in the Midwest. Attempts to contact the order in 1923 were unsuccessful.
Adolescent medicine Adult congenital heart disease Advanced heart failure and transplant cardiology Cardiovascular disease, dealing with disorders of the heart and blood vessels* Clinical cardiac electrophysiology Critical care medicine, is dealing with life-threatening conditions requiring intensive monitoring and treatment. Endocrinology, diabetes & metabolism, dealing with disorders of the endocrine system and its specific secretions called hormones Gastroenterology, concerned with the field of digestive diseases Geriatric medicine Hematology, concerned with blood, the blood-forming organs and its disorders. Hospice & palliative medicine Infectious disease, concerned with disease caused by a biological agent such as by a virus, bacterium or parasite Interventional cardiology Medical oncology, dealing with the chemotherapeutic (chemical) and/or immunotherapeutic (immunological) treatment of cancer Nephrology, dealing with the study of the function and diseases of the kidney Neurocritical care Pulmonary disease, dealing with diseases of the lungs and the respiratory tract Rheumatology, devoted to the diagnosis and therapy of rheumatic diseases Sleep medicine Sports medicine Transplant hepatology
Thirty years later, this work inspired, independently, two research groups to adopt the H-phosphonate chemistry to the solid-phase synthesis using nucleoside H-phosphonate monoesters 7 as building blocks and pivaloyl chloride, 2,4,6-triisopropylbenzenesulfonyl chloride (TPS-Cl), and other compounds as activators. The practical implementation of H-phosphonate method resulted in a very short and simple synthetic cycle consisting of only two steps, detritylation and coupling (Scheme 2). Oxidation of internucleosidic H-phosphonate diester linkages in 8 to phosphodiester linkages in 9 with a solution of iodine in aqueous pyridine is carried out at the end of the chain assembly rather than as a step in the synthetic cycle. If desired, the oxidation may be carried out under anhydrous conditions. Alternatively, 8 can be converted to phosphorothioate 10 or phosphoroselenoate 11 (X = Se), or oxidized by CCl4 in the presence of primary or secondary amines to phosphoramidate analogs 12. The method is very convenient in that various types of phosphate modifications (phosphate/phosphorothioate/phosphoramidate) may be introduced to the same oligonucleotide for modulation of its properties. Most often, H-phosphonate building blocks are protected at the 5'-hydroxy group and at the amino group of nucleic bases A, C, and G in the same manner as phosphoramidite building blocks (see below). However, protection at the amino group is not mandatory.
Sources: en.wikipedia.org
=== Autobiography === On October 20, 2009, Morgan's autobiography, I Am the New Black, was released. The book includes stories about living in Tompkins Projects in Bed-Stuy, Brooklyn, to becoming a cast member on Saturday Night Live. Morgan appeared on National Public Radio's Fresh Air hosted by Terry Gross, at times becoming very emotional about his former life in a New York ghetto.
== Research == Ben-Tal's research is in computational structural biology, with an emphasis on developing computational methods to study protein structure, function, motion, and evolution. His laboratory investigates molecular systems for which computational approaches can provide information that is difficult to obtain experimentally. His research has included computational studies of membrane proteins and transporters, including the human copper transporter 1, the ATP7B copper-transporting ATPase, and sodium/proton exchangers. His group has also developed methods for predicting the structures and motions of membrane proteins and has applied computational approaches to questions in protein evolution and drug discovery.
North-West Europe 1944–45 Tobruk 1941 Benghazi Raid North Africa 1940–43 Landing in Sicily Sicily 1943 Termoli Valli di Comacchio Italy 1943–45 Greece 1944–45 Adriatic Middle East 1943–44 Falkland Islands 1982 Western Iraq Gulf 1991
Dorsally located VA1 astrocytes, derived from p1 domain, express PAX6 and reelin. Ventrally located VA3 astrocytes, derived from p3, express NKX6.1 and SLIT1. Intermediate white-matter located VA2 astrocyte, derived from the p2 domain, which express PAX6, NKX6.1, reelin and SLIT1. After astrocyte specification has occurred in the developing CNS, it is believed that astrocyte precursors migrate to their final positions within the nervous system before the process of terminal differentiation occurs.
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.
一般不建议常温长期保存。多数说明指向 -20 °C 冷冻避光。常温运输通常被视为短期可接受，但会加快降解风险。