A practical reference on Certificate of analysis: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2026-04-14. Anything still debated is marked as such rather than presented as settled.
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.
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。
| Property | Value | Notes |
|---|---|---|
| Molecular class | Synthetic heptapeptide | Analog of an ACTH fragment |
| Amino acid length | Seven residues | Met-Glu-His-Phe-Pro-Gly-Pro |
| Origin | Moscow, 1980s | Institute of Molecular Genetics |
| Approved regions | Russia and some neighboring states | Not cleared in Western markets |
| Common trade names | Multiple national brands | Sold as a nasal formulation |
Semax is a synthetic heptapeptide whose sequence is Met-Glu-His-Phe-Pro-Gly-Pro. It was developed as a fragment analog of adrenocorticotropic hormone, modeled specifically on the ACTH(4-10) region. The first four residues reproduce that fragment, while a Pro-Gly-Pro tripeptide is appended at the C-terminus. Work on the compound originated in Russia, where it entered clinical use as an intranasal preparation. Its sequence places it among short regulatory peptides studied for effects on the central nervous system rather than on the adrenal axis.
The C-terminal Pro-Gly-Pro extension is not incidental. Proline-rich tails are known to resist several common peptidases, and the published literature attributes the longer half-life of Semax, relative to unmodified ACTH fragments, to this feature. The modification also removes the melanocyte-stimulating and corticosteroidogenic activity that characterizes longer ACTH-derived sequences. Because the molecule is small and hydrophilic, it is typically formulated as an aqueous solution for intranasal or parenteral delivery. Acetylation or amidation at the termini appears in closely related research peptides and shifts the mass by a fixed increment.
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.
== Burial methods == In many cultures, human corpses were usually buried in soil. The roots of burial as a practice reach back into the Middle Palaeolithic and coincide with the appearance of Homo neanderthalensis and Homo sapiens, in Europe and Africa respectively. As a result, burial grounds are found throughout the world. Through time, mounds of earth, temples, and caverns were used to store the dead bodies of ancestors. In modern times, the custom of burying dead people below ground, with a stone marker to indicate the burial place, is used in most cultures; although other means such as cremation are becoming more popular in the West (cremation is the norm in India and mandatory in big metropolitan areas of Japan). Some burial practices are heavily ritualized; others are simply practical.
=== ColdFusion Components (Objects) === ColdFusion was originally not an object-oriented programming language like PHP versions 3 and below. ColdFusion falls into the category of OO languages that do not support multiple inheritance (along with Java, Smalltalk, etc.). With the MX release (6+), ColdFusion introduced basic OO functionality with the component language construct which resembles classes in OO languages. Each component may contain any number of properties and methods. One component may also extend another (Inheritance). Components only support single inheritance. Object handling feature set and performance enhancing has occurred with subsequent releases. With the release of ColdFusion 8, Java-style interfaces are supported. ColdFusion components use the file extension cfc to differentiate them from ColdFusion templates (.cfm).
In Colombia, the laundering of billions of dollars, which come from drug trafficking, is carried out through imports of contraband from the parallel exchange market. In Central American countries such as Guatemala and Honduras, money laundering continues to increase in the absence of adequate legislation and regulations in these countries. Money laundering activities in Costa Rica have experienced substantial growth, especially using large-scale currency smuggling and investments of drug cartels in real estate, within the tourism sector. Furthermore, the Colon Free Zone in Panama, continues to be the area of operations for money laundering where cash is exchanged for products of different nature that are then put up for sale at prices below those of production for a return fast of the capital. In Mexico, the preferred techniques continue to be the smuggling of currency abroad, in addition to electronic transfers, bank drafts with Mexican banks and operations in the parallel exchange market. Money Laundering in the Caribbean countries continues to be a serious problem that seems to be very dangerous. Specifically, in Antigua, the Dominican Republic, Jamaica, Saint Vincent and the Grenadines. Citizens of the Dominican Republic who have been involved in money laundering in the United States, use companies that are dedicated to transferring funds sent to the Dominican Republic in amounts of less than $10,000 under the use of false names. Moreover, in Jamaica, multimillion-dollar asset laundering cases were discovered through telephone betting operations abroad.
Sources: en.wikipedia.org
Deoxyribozymes, also called DNAzymes or catalytic DNA, were first discovered in 1994. They are mostly single stranded DNA sequences isolated from a large pool of random DNA sequences through a combinatorial approach called in vitro selection or systematic evolution of ligands by exponential enrichment (SELEX). DNAzymes catalyze variety of chemical reactions including RNA-DNA cleavage, RNA-DNA ligation, amino acids phosphorylation-dephosphorylation, carbon-carbon bond formation, etc. DNAzymes can enhance catalytic rate of chemical reactions up to 100,000,000,000-fold over the uncatalyzed reaction. The most extensively studied class of DNAzymes is RNA-cleaving types which have been used to detect different metal ions and designing therapeutic agents. Several metal-specific DNAzymes have been reported including the GR-5 DNAzyme (lead-specific), the CA1-3 DNAzymes (copper-specific), the 39E DNAzyme (uranyl-specific) and the NaA43 DNAzyme (sodium-specific). The NaA43 DNAzyme, which is reported to be more than 10,000-fold selective for sodium over other metal ions, was used to make a real-time sodium sensor in cells.
In 1988, after prompting from the United States Congress, the National Institute of General Medical Sciences (National Institutes of Health) (NIGMS) instituted a funding mechanism for biotechnology training. Universities nationwide compete for these funds to establish Biotechnology Training Programs (BTPs). Each successful application is generally funded for five years then must be competitively renewed. Graduate students in turn compete for acceptance into a BTP; if accepted, then stipend, tuition and health insurance support are provided for two or three years during the course of their PhD thesis work. Nineteen institutions offer NIGMS supported BTPs. Biotechnology training is also offered at undergraduate level and in community colleges.
A later vertebrate study identified protein tyrosine phosphatase receptor F (PTPRF), a member of the LAR family, as a conserved cognate receptor for the glucogenic actions of asprosin. In zebrafish, two Ptprf paralogs (ptprfa/b) are expressed in liver, bind asprosin with nanomolar affinity, and are required for asprosin-induced hyperglycemia and upregulation of gluconeogenic genes; soluble Ptprf ligand-binding domains neutralize the glucogenic effects and lower basal glucose, while ptprfa/b knockout fish show hypoglycemia and a blunted response to asprosin but normal responses to glucagon. In mice, PTPRF is expressed in liver and binds asprosin; Ptprf-deficient animals exhibit impaired asprosin-induced glucose production and reduced hepatic G6pc and Pck1 induction, and Ptprf deletion improves glucose tolerance without altering Olfr734 expression. Mechanistically, the same study showed that asprosin promotes insulin receptor and Akt dephosphorylation via PTPRF, counteracting insulin's suppression of gluconeogenesis and suggesting that chronic asprosin–PTPRF signaling contributes to hepatic insulin resistance. Several other independent studies have confirmed asprosin's glucogenic function.
Sources: en.wikipedia.org
It originated at the Institute of Molecular Genetics in Moscow during the 1980s. The work was carried out by a Russian research group that specialized in peptide neuropharmacology.
It is registered as a medicine in Russia and has been used clinically there for decades. No regulatory agency in Western Europe or North America has approved it for any indication.
Semax corresponds to the four-to-ten fragment of adrenocorticotropic hormone. Because it omits the first three residues, it lacks the adrenal-stimulating action of the full hormone.
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。