If you have been reading about nasal formulation and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Last reviewed on 2026-06-23. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
Published research on this peptide originates mainly from Russian laboratories, and the wider international literature is comparatively thin. Studies have used rodent models of stroke, hypoxia, and memory tasks, with a smaller number of human trials reported. Reported outcomes include changes in attention and memory measures, along with effects on neurotrophic factor expression in some experiments. Small sample sizes, inconsistent dosing protocols, and limited independent replication are widely noted limitations, so the strength of the clinical evidence remains an open question.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Its chain combines the first seven residues of corticotropin with a C-terminal proline-glycine-proline extension, a modification intended to slow enzymatic breakdown. The free peptide has a molecular mass near 813.9 daltons. It belongs to the class of ACTH-derived fragments studied for central nervous system activity rather than for adrenal steroid stimulation. This structural relationship to a natural hormone fragment is the usual starting point for describing the compound in the literature.
Development took place during the 1980s at institutes of the Russian Academy of Sciences, where peptide fragments of ACTH were screened for cognitive and neuroprotective effects. The compound received regulatory approval in Russia as a nasal preparation, marketed for conditions such as ischemic stroke, transient ischemic attacks, and optic nerve disorders. Registration in other countries has not followed. Most published clinical reports originate from a small number of Russian research groups, and independent replication outside that setting remains limited. The regulatory status therefore differs sharply between Russia and the rest of the world.
Laboratory work points toward modulation of neurotrophic signaling, particularly expression of brain-derived neurotrophic factor and nerve growth factor in hippocampal tissue. Studies also describe effects on monoamine turnover, inflammatory mediators, and oxidative markers. These observations come mainly from animal models and cultured cells, so the causal chain in humans is not firmly established. Whether the reported molecular changes translate into measurable clinical benefit is an open question. Reviews generally present the mechanism as plausible rather than demonstrated.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Seven-residue peptide |
| Molecular mass | 813.9 Da | Monoisotopic value |
| Appearance | White to off-white powder | Lyophilized form |
| Solubility | Freely soluble in water | Also soluble in saline and polar solvents |
| Storage (dry) | -20 °C or lower | Desiccated, protected from light |
A team led by Enrico Fermi in 1934 found that bombarding uranium with neutrons produces beta rays (electrons or positrons from the elements produced; see beta particle). The fission products were at first mistaken for new elements with atomic numbers 93 and 94, which the Dean of the Sapienza University of Rome, Orso Mario Corbino, named ausenium and hesperium, respectively. The experiments leading to the discovery of uranium's ability to fission (break apart) into lighter elements and release binding energy were conducted by Otto Hahn and Fritz Strassmann in Hahn's laboratory in Berlin. Lise Meitner and her nephew, physicist Otto Robert Frisch, published the physical explanation in February 1939 and named the process "nuclear fission". Soon afterward, Fermi hypothesized that fission of uranium might release enough neutrons to sustain a fission reaction. Confirmation of this hypothesis came in 1939, and later work found that on average about 2.5 neutrons are released by each fission of uranium-235. Fermi urged Alfred O. C. Nier to separate uranium isotopes for determination of the fissile component, and on 29 February 1940, Nier used an instrument he built at the University of Minnesota to separate the world's first uranium-235 sample in the Tate Laboratory. Using Columbia University's cyclotron, John Dunning confirmed the sample to be the isolated fissile material on 1 March. Further work found that the far more common uranium-238 isotope can be transmuted into plutonium, which, like uranium-235, is also fissile by thermal neutrons.
=== STC1 === STC1 was discovered in 1995 from human kidney. It was demonstrated that human kidney extract produced the same calcium inhibitory action when injected in a fish. The gene that produce STC1, STC1 is located in the short arm of human chromosome 8 (position p21.2). STC1 mRNA is formed in heart, lung, liver, adrenal gland, prostate, and ovary, indicating that these are the sites of synthesis. Ovary contains the highest level of STC1 mRNA. Fish stanniocalcin and mammalian STC1 are closely related, and are about 50% similar in their structure. They are both responsible for calcium and phosphate balance. In mammals the predominant function of STC1 is to activate phosphate reabsorption in the small intestine and proximal tubules of the kidney.
==== Dissolution and reestablishment ==== On August 9, 2017, President Rodrigo Duterte signed Executive Order No. 38, revoking the Executive Order No. 183 signed by (former) President Benigno Aquino III on May 29 of 2015, due to the reason of the lack of funds to fully establish the NIR according to Benjamin Diokno, the Secretary of Budget and Management. Its dissolution upset the NIR regional officials and provoked strong negative reactions from the Negrenses. On June 13, 2024, Negros island together with neighboring Siquijor were grouped together under the reestablished Negros Island Region with the signing of Republic Act No. 12000 by President Bongbong Marcos.
Based on this, Tanzi has proposed that Alzheimer’s pathology - amyloid plaques, tau-tangles, and neuroinflammation - evolved as an orchestrated host defense system for the brain In other studies, Tanzi and his trainee, Zhongcong Xie, published several seminal papers providing the first evidence that the widely used general inhalant anesthetic, isoflurane, induces Abeta generation, apoptosis, and neurodegeneration in the mouse brain and post-operative CSF of patients. This has gradually led to a dramatic reduction in the clinical use of isoflurane in the operating room, especially in elderly patients and Alzheimer's patients. Music In musical pursuits, Tanzi has served as a studio keyboard player for Joe Perry and Aerosmith. He also co-wrote the tribute song to Alzheimer's patients called "Remember Me", performed by singer Chris Mann. He plays keyboards on the albums: Aerosmith: Music from Another Dimension by Aerosmith and Joe Perry's Switzerland Manifesto and Switzerland Manifesto MKII He has also performed with the legendary opera star, Renee Fleming.
Sources: en.wikipedia.org
Cardiomyoplasty is a surgical procedure in which healthy muscle from another part of the body is wrapped around the heart to provide support for the failing heart. Most often the latissimus dorsi muscle is used for this purpose. A special pacemaker is implanted to make the skeletal muscle contract. If cardiomyoplasty is successful and increased cardiac output is achieved, it usually acts as a bridging therapy, giving time for damaged myocardium to be treated in other ways, such as remodeling by cellular therapies.
=== Pharmacokinetics === The mean oral bioavailability of finasteride is approximately 65%. The absorption of finasteride is not affected by food. At steady-state with 1 mg/day finasteride, mean peak concentrations of finasteride were 9.2 ng/mL (25 nmol/L). Conversely, following a single 5 mg dose of finasteride, mean peak levels of finasteride were 37 ng/mL (99 nmol/L), and plasma concentrations increased by 47–54% following 2.5 weeks of continued daily administration. The volume of distribution of finasteride is 76 L. Its plasma protein binding is 90%. The drug has been found to cross the blood–brain barrier, whereas levels in semen were found to be undetectable. Finasteride is extensively metabolized in the liver, first by hydroxylation via CYP3A4 and then by aldehyde dehydrogenase. It has two major metabolites, which are the tert-butyl side chain monohydroxylated and monocarboxylic acid metabolites. These metabolites show approximately 20% of the inhibitory activity of finasteride on 5α-reductase. Hence, the metabolites of finasteride are not particularly active. The drug has a terminal half-life of 5 to 6 hours in adult men (18–60 years of age) and a terminal half-life of 8 hours or more in elderly men (more than 70 years of age). It is eliminated as its metabolites 57% in the feces and 40% in the urine.
PRCL's Role in Economic Development The role of PRCL in economic development of Pakistan is significant. PRCL awareness of increasing requirements of insurance and reinsurance of a progressive economy is making great efforts in coming up to national expectations. This progress signifies the consolidation of the position, both at home and abroad, encouraging further expansion.
Germany has a social market economy with a highly skilled labour force, a low level of corruption, and a high level of innovation. It is the largest economy in Europe by nominal GDP, as well as the world's third-largest by nominal GDP and sixth-largest by PPP-adjusted GDP. Its PPP-adjusted GDP per capita amounted to 115% of the EU average in 2024. The country's service sector contributes approximately 72% of the total GDP, the industrial sector 27%—with Germany having the largest manufacturing output in Europe—and its agricultural sector 1%, as of 2023. The unemployment rate published by Eurostat amounts to 3.2% as of January 2020, which is the fourth-lowest in the EU. Germany is part of the European single market which represents more than 450 million consumers. In 2017, the country accounted for 28% of the eurozone economy according to the International Monetary Fund. Germany introduced the common EU currency, the euro, in 2002. Its monetary policy is set by the European Central Bank, which is based in Frankfurt, the country's largest financial centre. Germany is the world's third-largest exporter and third-largest importer, and it has the second-largest trade surplus after China. Its largest trading partners in 2025 were China, the United States and the Netherlands. Germany's main exports are vehicles, machinery, and chemical goods. The German automotive industry is among the most competitive and innovative in the world. It was the sixth-largest by production and largest by export value in 2023.
== Medical uses == Flucloxacillin is an antibiotic used to treat lactational mastitis, skin infections, external ear infections, infections of leg ulcers, diabetic foot infections, and bone infections.
Sources: en.wikipedia.org
Oligonucleotide phosphorothioates (OPS) are modified oligonucleotides where one of the oxygen atoms in the phosphate moiety is replaced by sulfur. Synthesis of OPS is very similar to that of natural oligonucleotides. The difference is that the oxidation step is replaced by sulfur transfer reaction (sulfurization) and that the capping step is performed after the sulfurization.
== Protein == The human collagen alpha-1(XXI) chain is a 957-amino acid protein. As a FACIT collagen, it has a domain organization consisting of an N-terminal signal peptide followed by a single von Willebrand factor A (VWA) domain, a thrombospondin N-terminal (TSPN) domain, and a collagen triple-helical region that is interrupted by short non-collagenous segments. This interrupted triple-helical structure is the defining feature of the FACIT subfamily, whose members associate with the surfaces of major fibril-forming collagens rather than forming fibrils on their own. The mature protein is secreted into the extracellular space and localizes to the extracellular matrix.
The vagina extends upward from the aperture and becomes the egg gland. In some jawless fish, there is neither oviduct nor vagina and instead the egg travels directly through the body cavity (and is fertilised externally as in most fish and amphibians). In insects and other invertebrates, the vagina can be a part of the oviduct (see insect reproductive system). Birds have a cloaca into which the urinary, reproductive tract (vagina) and gastrointestinal tract empty. Females of some waterfowl species have developed vaginal structures called dead end sacs and clockwise coils to protect themselves from sexual coercion. A lack of research on the vagina and other female genitalia, especially for different animals, has stifled knowledge on female sexual anatomy. One explanation for why male genitalia is studied more includes penises being significantly simpler to analyze than female genital cavities, because male genitals usually protrude and are therefore easier to assess and measure. By contrast, female genitals are more often concealed, and require more dissection, which in turn requires more time. Another explanation is that a main function of the penis is to impregnate, while female genitals may alter shape upon interaction with male organs, especially as to benefit or hinder reproductive success. Non-human primates are optimal models for human biomedical research because humans and non-human primates share physiological characteristics as a result of evolution.
With increased concerns about nuclear waste, breeding fuel cycles came under renewed interest as they can reduce actinide wastes, particularly plutonium and minor actinides such as neptunium, americium and curium. Breeder reactors are designed to fission the actinide wastes as fuel and thus convert them to more fission products. For unreprocessed uranium-oxide spent nuclear fuel, Bodansky's 2006 review described a rapid initial decrease in radioactivity as short-lived fission products decay, followed by a more gradual decrease as actinides decay. Today's commercial light-water reactors do breed some new fissile material, mostly in the form of plutonium. Because commercial reactors were never designed as breeders, they do not convert enough uranium-238 into plutonium to replace the uranium-235 consumed. Nonetheless, at least one-third of the power produced by commercial nuclear reactors comes from fission of plutonium generated within the fuel. Even with this level of plutonium consumption, light water reactors consume only part of the plutonium and minor actinides they produce, and nonfissile isotopes of plutonium build up, along with significant quantities of other minor actinides. Since breeder reactors on a closed fuel cycle would use nearly all of the isotopes of these actinides fed into them as fuel, their fuel requirements would be reduced by a factor of about 100. Waste volume alone does not determine disposal requirements. A 2023 DOE assessment identified radionuclide inventory, heat output, chemical and physical properties, and packaging as relevant factors.
Sources: en.wikipedia.org
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.
The extension was introduced to slow enzymatic breakdown of the peptide in biological systems. Natural ACTH fragments are degraded rapidly by peptidases. Adding the tripeptide was intended to extend the window during which the molecule remains intact.
Most published work consists of animal experiments conducted in a small number of laboratories. Human data are limited in number and size. Whether the observed effects translate into reliable clinical benefit is still unresolved.
Semax is a synthetic seven-amino-acid peptide derived from a fragment of corticotropin. It is used in Russia as a nasal preparation, while elsewhere it is studied as a research compound. It is not approved as a medicine in most countries.