Everything below concerns heptapeptide. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2026-04-29. Numbers and descriptions here follow the published literature rather than marketing material.
The compound was developed in the 1980s at the Institute of Molecular Genetics in Moscow, where it emerged from research on short ACTH fragments and their effects on the central nervous system. Russian pharmaceutical listings describe it as a nootropic and neuroprotective agent, most often formulated as nasal drops. It is not a marketed medicine in the United States or the European Union, and no pharmacopoeial monograph covers it. Consequently, most published clinical experience with the substance originates from a small number of research centres, mainly in Russia and neighbouring countries.
Pharmacological accounts link semax to melanocortin signalling and to modulation of neurotrophic factor expression, particularly brain-derived neurotrophic factor and nerve growth factor. Much of this evidence comes from rodent studies using intranasal delivery, a route chosen because it allows peptides to reach the central nervous system with limited systemic exposure. Whether the same mechanisms operate in humans at comparable magnitude remains an open question. The precise receptor or receptors responsible for the reported behavioural and neuroprotective effects have not been conclusively identified.
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.
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 formula | C37H51N9O10S | Free acid form of the heptapeptide; depends on terminal groups |
| Molecular mass | About 813.9 g/mol | Average mass used for mass spectrometry confirmation |
| Appearance | White to off-white solid | Supplied as a lyophilised powder; hygroscopic |
| Solubility class | Freely soluble in aqueous media | Water, saline, and phosphate buffers; limited organic solubility |
| Typical storage temperature | -20 degrees Celsius | Long term and dry; short working periods may use 2 to 8 degrees Celsius |
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.
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.
当时的短肽研究普遍关注能否穿越血脑屏障、在低剂量下产生中枢效应，Semax 属于这一路线。鼻内给药是其主要使用方式，俄语文献报道的适应症涵盖缺血性卒中、短暂性脑缺血发作、认知功能减退以及视神经病变。这些研究大多发表在当地期刊上，样本规模与终点设置同西方试验惯例存在差异，国际同行对其临床证据的强度看法不一。
各国监管态度分化明显。俄罗斯按处方药管理，部分东欧国家留有使用记录；欧盟与美国未批准其作为药物上市，市面流通品通常标注为研究用化学品。身份差异意味着标示含量、纯度与无菌性缺少统一核查。体育领域还牵涉反兴奋剂名录，跨境携带则受目的地药品法规约束。
== P == Paraphilic Disorder Peritoneum disorders Personality disorders Pervasive developmental disorders Post-traumatic stress disorders Psychiatric disorders, i.e., mental illness Psychoactive substance abuse disorders Psychological disorders, i.e., mental illness Psychotic disorders Puerperal disorders
The operating room time required to harvest, refine, and emplace fat to the breasts is greater than the usual 2-hour OR time; the usual infiltration time was approximately 2 hours for the first 100 cm3 volume, and approximately 45 minutes for injecting each additional 100 cm3 volume of breast-filler fat. The technique for injecting fat grafts for breast augmentation allows the plastic surgeon great control in sculpting the breasts to the required contour, especially in the correction of tuberous breast deformity. In which case, no fat-graft is emplaced beneath the nipple-areola complex (NAC), and the skin envelope of the breast is selectively expanded (contoured) with subcutaneously emplaced body-fat, immediately beneath the skin. Such controlled contouring selectively increased the proportional volume of the breast in relation to the size of the nipple-areola complex, and thus created a breast of natural form and appearance; greater verisimilitude than is achieved solely with breast implants. The fat-corrected, breast-implant deformities, were inadequate soft-tissue coverage of the implant(s) and capsular contracture, achieved with subcutaneous fat-grafts that hid the implant-device edges and wrinkles, and decreased the palpability of the underlying breast implant. Furthermore, grafting autologous fat around the breast implant can result in softening the breast capsule.
It allows for the highest levels of exercise intensity, but intramuscular stores of phosphocreatine are very limited and can only provide energy for exercises lasting up to ten seconds. Recovery is very quick, with full creatine stores regenerated within five minutes.
Sources: en.wikipedia.org
Intarcia Therapeutics is an American biopharmaceutical company based in Boston, MA and incorporated under the laws of Delaware. It was founded in 1995 under the name "BioMedicines" and changed to its present name in 2004. In 2013, Intarcia relocated its headquarters to Boston, keeping its manufacturing facility in Hayward, CA. In addition to Boston and Hayward, Intarcia also has a location in Research Triangle Park, North Carolina, where it discovers and develops peptides for its drug delivery system. In 2005, the executive leadership of Intarcia was largely vested in two people, Karling Leung and James Ahlers, President/CEO/Director and Vice President/CFO/Finance & Operations Officer, respectively. By 2012, Kurt Graves had replaced Karling Leung as President and CEO. Kurt Graves has been with Intarcia since August 2010, first serving as Executive Chairman before becoming President and CEO in April 2012. As of 2016, Intarcia is engaged in development of a "potential once-a-year type 2 diabetes treatment". Referred to as ITCA 650, the therapeutic consists of exenatide delivered via its Medici Drug Delivery System, "a drug delivery platform that stabilizes and delivers therapeutic proteins and peptides". The drug was rejected for FDA approval in 2017 and 2020.
=== Purification === The biotin tag can be used in affinity chromatography together with a column that has avidin (or streptavidin or neutravidin) bound to it, which is the natural ligand for biotin. However, harsh conditions (e.g., 6M GuHCl at pH 1.5) are needed to break the avidin/streptavidin - biotin interaction, which will most likely denature the protein carrying the biotin tag. If isolation of the tagged protein is needed, it is better to tag the protein with iminobiotin. This biotin analogue gives strong binding to avidin/streptavidin at alkaline pH, but the affinity is reduced upon lowering the pH. Therefore, an iminobiotin-tagged functional protein can be released from an avidin/streptavidin column by decreasing the pH (to around pH 4).
=== 28 November === The Russian army was actively pushing on both sides of Bakhmut, in Donetsk Oblast. The Russians were trying to encircle the town but were making very slow progress, according to observers.
Sources: en.wikipedia.org
6 April – The new England women's national football team home kit is worn for its inaugural match as England participates in the 2023 Women's Finalissima against Brazil. At Wembley Stadium, England beat Brazil 4–2 in a penalty shootout to win their first Finalissima. 8 April – The NASUWT is to ballot its members on strike action after 87% of those who voted rejected the government's pay offer for teachers in England, which the union says fails to address concerns over pay and conditions. 11 April – Junior doctors in England begin a four-day strike. 14 April – Two police officers are dismissed from the Metropolitan Police over offensive WhatsApp messages, some of them including offensive comments about model Katie Price's son, Harvey. The Royal College of Nursing rejects a pay offer for nurses in England and announces a 48-hour strike from 8pm on 30 April to 8pm on 2 May. UNISON confirms its members working for the NHS have voted unanimously to accept a 5% pay offer from the UK government. Following a trial at Derby Crown Court, Stephen Boden and partner Shannon Marsden are convicted of the murder of their ten-month-old son Finley Boden on Christmas Day 2020, 39 days after he had been returned to them by social services. 15 April – Merseyside Police say that 118 people have been arrested at Aintree Racecourse after protestors delay the start of the 2023 Grand National. The race, which is delayed by 14 minutes, is won by Corach Rambler, ridden by Derek Fox.
Also, alphaproteobacteria present a potentially large source of the lipid in the rock record. It has been suggested that these organisms may be synthesizing gammacerane in response to other shifting parameters during water column stratification, as most of the bacteria that contain the ths gene thrive in dynamic environments.
Richard Küch (1860-1915) was able to melt quartz glass - the basis for UV radiation sources - for the first time in 1890 and founded the Heraeus Quarzschmelze. He developed the first quartz lamp (sun lamp) for generating UV radiation in 1904, thus laying the foundation for this form of light therapy. Despite the dosage problems, doctors increasingly used quartz lamps in the early 20th century. Internal medicine specialists and dermatologists were among the most eager testers. After successful treatment of skin tuberculosis, internal medicine began to treat tuberculous pleurisy, glandular tuberculosis and intestinal tuberculosis. In addition, doctors tested the effect of quartz lamps on other infectious diseases such as syphilis, metabolic diseases, cardiovascular diseases, nerve pain such as sciatica, or nervous diseases such as neurasthenia and hysteria. In dermatology, fungal diseases, ulcers and wounds, psoriasis, acne, freckles and hair loss were also treated with quartz lamps, while in gynecology, abdominal diseases were treated with quartz lamps. Rejuvenation specialists used artificial high-altitude sunlight to stimulate gonadal activity and treated infertility, impotentia generandi (inability to conceive), and lack of sexual desire by irradiating the genitals. For this purpose, Philipp Keller (1891-1973) developed an erythema dosimeter with which he measured the amount of radiation not in Finsen units (UV radiation with a wavelength λ of 296.7 nm and an irradiance E of 10−5 W/m2), but in height solar units (HSE).
Sources: en.wikipedia.org
It is described as a synthetic analogue of the ACTH(4–10) fragment, a short segment of adrenocorticotropic hormone. Its sequence differs from that fragment and includes two proline residues, which influence stability and behaviour in solution.
It appears in Russian pharmaceutical listings as a nasal formulation, but it is not an authorised medicine in the United States or the European Union. Outside those markets it is normally encountered as a research chemical rather than a prescription product.
Laboratory and animal work points to melanocortin signalling and changes in neurotrophic factor levels, especially brain-derived neurotrophic factor. The exact receptor targets and the degree to which these findings transfer to humans are still unresolved.
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.