This is a working overview of intranasal delivery, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2025-09-10. 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.
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.
| 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 |
Routine characterization relies on reversed-phase high-performance liquid chromatography to establish purity and on mass spectrometry to confirm molecular identity. Electrospray ionization and matrix-assisted laser desorption ionization are both used for mass verification. Amino acid analysis and peptide mapping can detect sequence errors. Common impurities include truncated sequences, methionine sulfoxide formed by oxidation, and deamidated products. Chromatograms are usually recorded near 214 nm, where the peptide backbone absorbs, and purity is reported as the percentage area of the principal peak.
Verification of a supplied batch generally combines a certificate of analysis with independent testing, because certificates are self-reported documents. A typical package includes a chromatographic trace, a mass spectrum, and a stated water or counter-ion content. Batch-to-batch consistency matters more than a single purity figure when results are compared across experiments. No single mandatory standard governs research-grade peptide release, so laboratories are expected to define their own acceptance criteria. Residual trifluoroacetate from purification is a frequently overlooked counter-ion.
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.
=== Binary, anionic === Group 3 elements scandium and yttrium, as well as lanthanum, form the 20-electron monoanions [Sc(CO)8]−, [Y(CO)8]−, and [La(CO)8]−. Group 4 elements as dianions resemble neutral group 6 derivatives: [Ti(CO)6]2−. Group 5 elements as monoanions resemble again neutral group 6 derivatives: [V(CO)6]−. Group 6 elements form (inter alia) anions with the lowest known oxidation state for transition metals: Cr(CO)4−3, Mo(CO)4−3, and W(CO)4−3. Group 7 elements as monoanions resemble neutral group 8 derivatives: [Mn(CO)5]−, [Tc(CO)5]−, [Re(CO)5]−. Group 8 elements as dianaions resemble neutral group 10 derivatives: [Fe(CO)4]2−, [Ru(CO)4]2−, [Os(CO)4]2−. Condensed derivatives are also known. Group 9 elements as monoanions resemble neutral group 10 metal carbonyl. [Co(CO)4]− is the best studied member. Large anionic clusters of nickel, palladium, and platinum are also well known. Many metal carbonyl anions can be protonated to give metal carbonyl hydrides.
Seaport terminals handle a wide range of maritime cargoes. Break bulk / general cargo are goods that are handled and stowed piecemeal to some degree, as opposed to cargo in bulk or modern shipping containers. They are typically bundled in batches for hoisting, (with cargo nets, slings or crates), or stacked on trays, pallets or skids. They are generally lifted directly into and out of a vessel's holds, by cranes or derricks present on the dock or on the ship itself. If hoisted onto the deck instead of straight into the hold, cargo then is manhandled and stowed by stevedores. Securing break bulk and general freight inside a vessel includes the use of dunnage. When no hoisting equipment is available, break bulk would previously be man-carried on and off the ship, over a plank, or by passing via human chain. Since the 1960s, the volume of break bulk cargo has enormously declined worldwide in favour of mass adoption of containers. Bulk cargo, such as salt, oil, tallow, but also scrap metal, is usually defined as commodities that are neither on pallets nor in containers. Bulk cargoes are not handled as individual pieces, the way heavy-lift and project cargo are. Alumina, grain, gypsum, logs, and wood chips, for instance, are bulk cargoes. Bulk cargo is classified as liquid or dry.
February 27, 2009: Finland Statistics Finland informs that Finland's gross domestic product diminished by 1.3% in the last quarter of 2008 from the previous quarter. The growth slowed down already in early 2008 and in the third quarter output diminished by 0.3% from the previous quarter.
Sources: en.wikipedia.org
=== Primary === The development of osteoarthritis is correlated with a history of previous joint injury and with obesity, especially with respect to the hips and knees. Osteoarthritis of the hips and knees is twice as common in those with obesity. Changes in sex hormone levels may play a role in the development of osteoarthritis, as it is more prevalent among post-menopausal women than among men of the same age. Women also tend to have more severe symptoms and imaging findings for hip and knee osteoarthritis as compared to men. Conflicting evidence exists for the differences in hip and knee osteoarthritis in African Americans and Caucasians.
The cold surges on the eastern slopes of the Rocky Mountains, Iceland, New Zealand, and eastern Asia differ from the cold air damming east of the Appalachians due to the wider mountain ranges, sloping terrain, and lack of an eastern body of warm water.
2C-B tablets often contain a dose of 5 or 10 mg of the drug. Low doses of 2C-B like 5 to 10 mg orally are said to produce stimulation, entactogen-like effects, and perceptual enhancement, while higher doses like 10 to 20 mg orally are said to produce psychedelic and hallucinogenic effects. 2C-B is frequently used at low doses as a substitute for MDMA. It is often used by people who go to electronic music festivals, also known as raves. The drug is also frequently used at clubs and parties, at home, or in nature. 2C-B is often combined with other drugs, such as MDMA, alcohol, and cannabis. Besides recreational use, 2C-B has been used in psychedelic-assisted psychotherapy at doses of 15 to 30 mg orally.
Radium has 33 known isotopes with mass numbers from 202 to 234, all of which are radioactive. Four of these – 223Ra (half-life 11.4 days), 224Ra (3.64 days), 226Ra (1600 years), and 228Ra (5.75 years) – occur naturally in the decay chains of primordial thorium-232, uranium-235, and uranium-238 (223Ra from uranium-235, 226Ra from uranium-238, and the other two from thorium-232). These isotopes nevertheless still have half-lives too short to be primordial radionuclides, and only exist in nature from these decay chains. Together with the mostly artificial 225Ra (15 d), which occurs in nature only as a decay product of minute traces of neptunium-237, these are the five most stable isotopes of radium. All other 27 known radium isotopes have half-lives under two hours, and the majority have half-lives under a minute. Of these, 221Ra (half-life 28 s) also occurs as a 237Np daughter, and 220Ra and 222Ra would be produced by the still-unobserved double beta decay of natural radon isotopes. At least 12 nuclear isomers have been reported, the most stable of which is radium-205m with a half-life between 130~230 milliseconds; this is still shorter than twenty-four ground-state radium isotopes. 226Ra is the most stable isotope of radium and is the last isotope in the (4n + 2) decay chain of uranium-238 with a half-life of over a millennium; it makes up almost all of natural radium. Its immediate decay product is the dense radioactive noble gas radon (specifically the isotope 222Rn), which is responsible for much of the danger of environmental radium.
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 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.