A practical reference on reversed-phase HPLC: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2026-07-15. Anything still debated is marked as such rather than presented as settled.
Development is attributed to researchers at the Institute of Molecular Genetics in Moscow during the early 1980s, building on earlier Soviet work with ACTH fragments. Russian regulatory approval followed for intranasal use, and the compound has remained commercially available there for decades. Most published human data originate from Russian and, later, some Eastern European clinical reports, which are not always accessible in English translation. Outside that region the material is generally handled as a research chemical rather than a licensed medicine.
Regulatory status differs sharply between jurisdictions. In Russia the peptide is registered as a prescription nasal preparation, while agencies such as the United States Food and Drug Administration have not approved it for any indication. Products sold elsewhere are typically labeled for laboratory research only, and such labels shift responsibility for safe handling to the purchaser. Because the same name covers pharmaceutical-grade nasal drops and bulk research powder, identity and purity documentation becomes the main practical concern when comparing sources.
Semax is a synthetic seven-amino-acid peptide whose sequence extends the ACTH(4-10) fragment with a C-terminal proline-glycine-proline tripeptide. The commonly cited sequence is Met-Glu-His-Phe-Pro-Gly-Pro, giving a molecular formula near C37H51N9O10S and a molecular weight close to 813.9 g/mol. It belongs to the broader class of synthetic ACTH fragments studied for central nervous system effects rather than for adrenal steroid stimulation. In practice the material appears as a lyophilized white powder for laboratory work or as a dilute saline solution in clinical settings.
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.
Proposed mechanisms center on neurotrophic signaling rather than on classical melanocortin receptor activation. Rodent experiments have reported shifts in the expression of brain-derived neurotrophic factor and nerve growth factor after administration, together with changes in the associated receptor systems. Several authors argue that the peptide acts largely through its degradation products and their interaction with peptidergic pathways, but this remains a hypothesis rather than a settled finding. No single molecular target has been identified in a way that the field broadly accepts.
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.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide (ACTH fragment analog) | Not a steroid; does not belong to the melanocortin agonist drugs by marketing category |
| Molecular formula | C37H51N9O10S (commonly cited) | Reported values vary slightly with salt and counter-ion content |
| Appearance | White to off-white lyophilized powder | A single batch may appear as a loose cake or fluffy solid |
| Solubility | Freely soluble in water and aqueous buffer | Stock solutions are usually prepared in sterile water or saline |
| Typical storage | −20 °C or below, desiccated and protected from light | Seal opened vials promptly to limit moisture uptake |
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.
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 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 peptide created in the Soviet Union during the early 1980s by researchers working in Moscow. It was built from the short adrenocorticotropic hormone fragment known as ACTH(4-10), and the chain was then extended with three additional amino acids. The resulting molecule was named semax and entered clinical use in Russia in 1994. It is generally described as a nootropic and neuroprotective agent rather than as a hormone analogue.
The parent fragment ACTH(4-10) carries the sequence Met-Glu-His-Phe-Arg-Trp-Gly. Semax replaces the arginine and tryptophan positions with a proline-glycine-proline tail, giving Met-Glu-His-Phe-Pro-Gly-Pro. That change removes residues associated with adrenal stimulation, so the peptide does not drive cortisol release the way full ACTH does. This distinction shapes how the compound is grouped in the literature, where it sits with neuropeptides and peptide neuromodulators rather than with corticosteroids.
Regulatory status varies sharply by country. Semax is registered for medical use in Russia, where it appears in formularies as a nasal solution, and it also holds registration in a small number of neighbouring states. It has no approval from the United States Food and Drug Administration or the European Medicines Agency, and it is not a scheduled controlled substance in most jurisdictions. Elsewhere it circulates mainly as laboratory material, so purity documentation comes from suppliers rather than from a national pharmacopoeia.
Fluid mechanics is the branch of physics concerned with the mechanics of fluids (liquids, gases, and plasmas) and the forces on them. Originally applied to water (hydromechanics), it found applications in a wide range of disciplines, including mechanical, aerospace, civil, chemical, and biomedical engineering, as well as geophysics, oceanography, meteorology, astrophysics, and biology. It can be divided into fluid statics, the study of various fluids at rest; and fluid dynamics, the study of the effect of forces on fluid motion. It is a branch of continuum mechanics, a subject which models matter without using the information that it is made out of atoms; that is, it models matter from a macroscopic viewpoint rather than from microscopic. Fluid mechanics, especially fluid dynamics, is an active field of research, typically mathematically complex. Many problems are partly or wholly unsolved and are best addressed by numerical methods, typically using computers. A modern discipline, called computational fluid dynamics (CFD), is devoted to this approach. Particle image velocimetry, an experimental method for visualizing and analyzing fluid flow, also takes advantage of the highly visual nature of fluid flow.
Thymosin α1 is a peptide fragment derived from prothymosin alpha, a protein that in humans is encoded by the PTMA gene. It was the first of the peptides from Thymosin Fraction 5 to be completely sequenced and synthesized. Unlike β thymosins, to which it is genetically and chemically unrelated, thymosin α1 is produced as a 28-amino acid fragment having the sequence Ac-SDAAVDTSSEITTKDLKEKKEVEEEAEN, which is made from cleavage of a longer, 113-amino acid precursor, prothymosin α.
From the mid-19th century to the 1930s, American physicians prescribed Cannabis sativa as a prescription drug for various medical conditions. In the 1960s, the counterculture movement introduced the use of psychoactive drugs, including cannabis. Young adults and college students reported the recreational prevalence of cannabis, among other drugs, at 20-25% while the cultural mindset of using was open and curious. In 1969, the FBI reported that between the years 1966 and 1968, the number of arrests for marijuana possession, which had been outlawed throughout the United States under Marijuana Tax Act of 1937, had increased by 98%. Despite acknowledgement that drug use was greatly growing among America's youth during the late 1960s, surveys have suggested that only as much as 4% of the American population had ever smoked marijuana by 1969. By 1972, however, that number would increase to 12%. That number would then double by 1977. The Controlled Substances Act of 1970 classified marijuana along with heroin and LSD as a Schedule I drug, i.e., having the relatively highest abuse potential and no accepted medical use. Most marijuana at that time came from Mexico, but in 1975 the Mexican government agreed to eradicate the crop by spraying it with the herbicide paraquat, raising fears of toxic side effects. Colombia then became the main supplier. The "zero tolerance" climate of the Reagan and Bush administrations (1981–1993) resulted in passage of strict laws and mandatory sentences for possession of marijuana.
==== Approximated wavefunction of the deuteron ==== The deuteron wavefunction must be antisymmetric if the isospin representation is used (since a proton and a neutron are not identical particles, the wavefunction need not be antisymmetric in general). Apart from their isospin, the two nucleons also have spin and spatial distributions of their wavefunction. The latter is symmetric if the deuteron is symmetric under parity (i.e. has an "even" or "positive" parity), and antisymmetric if the deuteron is antisymmetric under parity (i.e. has an "odd" or "negative" parity). The parity is fully determined by the total orbital angular momentum of the two nucleons: if it is even then the parity is even (positive), and if it is odd then the parity is odd (negative). The deuteron, being an isospin singlet, is antisymmetric under nucleons exchange due to isospin, and therefore must be symmetric under the double exchange of their spin and location. Therefore, it can be in either of the following two different states:
Cold Stone has entered into partnerships with other companies to promote brand name products inside its stores. The first major partnership the company entered into was with Kraft Foods for its Jell-O brand in 2009. Cold Stone introduced a series of flavors of ice cream based on popular Jell-O pudding flavors; Chocolate, Butterscotch, Banana, and Vanilla. Because the pudding additives cause the ice cream to gel, it was recently noted that these flavors do not melt. Externally, a 2008 licensing agreement with Jelly Belly had a line of jelly beans flavored like some of Cold Stone's most popular ice cream flavors.
Sources: en.wikipedia.org
The dragonless Aemond claims Vhagar, which leads to a fight between Alicent and Rhaenyra's children where Luke slashes one of Aemond's eyes out. They are all brought before Viserys in a mass gathering, where a furious Alicent demands one of Luke's eyes to be taken out as retribution, arguing with Rhaenyra who defends her kids. After Viserys refuses to abide by Alicent's demand, she grabs his Valyrian steel dagger and rushes towards Luke, but is blocked by Rhaenyra. Aemond asserts that the loss of his eye in exchange for gaining a dragon was a fair trade, and Viserys considers the matter settled under those conditions. He also declares that anyone claiming Rhaenyra's children to be bastards will lose their tongue. Viserys reinstates Otto as his Hand (as Lyonel had recently perished in a fire), where he and Alicent conspire to solidify their family's positions at court while Rhaenyra and Daemon unite to counter their influence over the court. Six years later, Viserys' health has greatly declined, as his face is partially disfigured and he is frequently bedridden. Otto and Alicent have de facto control over royal matters, as Viserys frequently drinks milk of the poppy and has declining mental acuity. Corlys' younger brother Vaemond petitions the crown to be named as Corlys' heir instead of Luke, who he accuses of being a bastard. Otto presides over the matter and is inclined to rule against Luke, but a frail Viserys shows up to the throne room to oversee the matter himself, walking to the Iron Throne with great difficulty and support from Daemon.
== Biography == Born in 1937 in Rome, Mendes Nassi is descended from a line of physicians. His grandfather, Guido Aaron Mendes, directed the Red Cross Hospital in Rome during the 1930s. As Italian Fascist law instituted a regime of prejudice against Jews in Italy, he moved his family to Switzerland to await British permission to enter the territory of Palestine, later to become the state of Israel. These certificates were obtained with the direct intervention of Pope Pius 12th, a classmate and close friend to Guido. The family moved to Gedera in Israel where David’s father, Maor Mendes and his grandfather pioneered the treatment and obliteration of Tuberculosis in Israel. During the 1947–1949 Palestine war the family moved to Ramat Gan, where he graduated from Ohel Shem high school. During his time in Ramat Gan, he practiced fencing and went on to become captain of the Israeli team. He won all national foil competitions in Israel between the years 1955 and 1963. He then joined the army and married his childhood friend, Nili Shmueli. In 1965 David relocated with his family to the United States to continue his training. He remained in New York City until 1975 when he returned to Israel with his wife and two children, Ido and Sharone. His third child, Yonni, was born in Haifa a few years later.
A foreign-body giant cell is a collection of fused macrophages (giant cell) which are generated in response to the presence of a large foreign body. This is particularly evident with catheters, parasites, or biomaterials that are inserted into the body for replacement or regeneration of diseased or damaged tissues. Foreign body giant cells are also produced to digest foreign material that is too large for phagocytosis. The inflammatory process that creates these cells often leads to a foreign body granuloma. The human body goes through several steps when exposed to foreign biomaterial including acute and chronic inflammation, and formation of new tissue and a fibrous capsule along the surface of the implantation. Foreign body reactions, which are a type of chronic inflammation, are characterized by the presence of macrophages, monocytes, and foreign-body giant cells (FBGCs). The response of the foreign body reaction determines how compatible the implanted material will be in the body, and the members of the foreign body reaction, including the FBGC's, remain along the surface of the biomaterial for its lifetime in the body. Foreign body giant cells are formed through signaling from IL-4 and IL-13, and may fuse to produce a multinucleated cell with up to 200 nuclei within its cytoplasm.
Although developing, telomerase inhibition within malignant cancer cells can theoretically be used as a potential treatment. Real-time reverse transcription polymerase chain reaction (RT-PCR) quantifying hTERT expression in various tumor samples verified this varying expression. Telomeres in non-cancerous human cells are generally longer than in cancer cells, and telomerase-inhibiting therapy aims to selectively suppress telomerase activity in cancer cells while preserving normal telomerase activity in non-tumor cells. Telomere-targeted treatments include oligonucleotides, nucleosides, small molecule inhibitors, and more. Various natural compounds have been identified as having telomerase inhibitory properties, such as oleic acid, a fatty acid found in vegetable and animal oils.
Sources: en.wikipedia.org
==== Hawaii ==== In Hawaii, where cuisine is heavily influenced by Asian cultures, glass noodles are known locally as long rice, supposedly because the process of making the noodles involves extruding the starch through a potato ricer. They are used most often in chicken long rice, a dish of glass noodles in chicken broth that is often served at luaus.
=== Phase II - conjugation === In subsequent phase II reactions, these activated xenobiotic metabolites are conjugated with charged species such as glutathione (GSH), sulfate, glycine, or glucuronic acid. These reactions are catalysed by a large group of broad-specificity transferases, which in combination can metabolise almost any hydrophobic compound that contains nucleophilic or electrophilic groups. One of the most important of these groups are the glutathione S-transferases (GSTs). The addition of large anionic groups (such as GSH) detoxifies reactive electrophiles and produces more polar metabolites that cannot diffuse across membranes, and may, therefore, be actively transported.
Monobenzone, also called 4-(Benzyloxy)phenol and monobenzyl ether of hydroquinone (MBEH) is an organic chemical in the phenol family with chemical formula C6H5CH2OC6H4OH. It is used as a topical drug for medical depigmentation. It is a colourless solid that is classified as the monobenzyl ether of hydroquinone. Monobenzone is soluble in alcohol, benzene, and diethyl ether, and practically insoluble in water.
Sources: en.wikipedia.org
It is a short synthetic peptide built from seven amino acids: methionine, glutamic acid, histidine, phenylalanine and three prolines. The sequence derives from the 4-10 fragment of adrenocorticotropic hormone with an added proline-glycine-proline tail. No plant or animal extract is involved; the material is produced by solid-phase peptide synthesis.
It was developed in the Soviet Union during the early 1980s by groups at the Institute of Molecular Genetics in Moscow. Russian approval for intranasal use followed, and it has been marketed there since. Western laboratories encountered it mainly through translated literature and, later, through online research-chemical trade.
It holds a Russian registration as a prescription nasal product but has no approval from the European Medicines Agency or the United States Food and Drug Administration. Buyers outside Russia usually receive material sold strictly for laboratory research. That distinction matters because research-grade and pharmaceutical-grade products carry different documentation and testing expectations.
The main proposal is modulation of neurotrophic factors such as brain-derived neurotrophic factor, supported largely by animal experiments. Receptor-level targets have not been firmly established. Most reviews describe the mechanism as only partially characterized.