intranasal route raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2025-12-26. Anything still debated is marked as such rather than presented as settled.
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.
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.
| 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 |
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.
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.
Dissolution is normally performed in water, phosphate-buffered saline, or normal saline, since the peptide is freely soluble in aqueous media and is rarely handled with strong organic solvents. Solution pH should be kept near neutral, because extreme acidity or alkalinity accelerates backbone hydrolysis and encourages oxidation of the methionine side chain. Once dissolved, the material is less stable than the dry powder and is commonly divided into single-use portions and frozen. Buffers containing primary amines, such as Tris, are often avoided because of possible side reactions.
Purity assessment relies mainly on reversed-phase high-performance liquid chromatography, which separates the target heptapeptide from truncated sequences, deletion analogues, and oxidised forms. Mass spectrometry, usually coupled to liquid chromatography, confirms identity through the expected molecular ion and reveals modifications such as methionine sulfoxide formation. Amino acid analysis can verify composition, and tandem mass spectrometry supports sequence confirmation. Ultraviolet detection near 254 to 280 nanometres is convenient because the phenylalanine and histidine residues absorb in that region. Nuclear magnetic resonance is rarely used for routine release testing.
Semax 是人工设计的七肽，序列为 Met-Glu-His-Phe-Pro-Gly-Pro，骨架取自促肾上腺皮质激素片段 ACTH(4-10)。它于二十世纪八十年代在苏联的分子遗传学研究机构内合成。设计目标是保留该片段与注意力和记忆相关的活性，同时剔除促皮质激素释放等内分泌作用。此后俄罗斯将其登记为药品并进入临床使用。
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。
The production of kimono started to use Western technologies such as synthetic dye, and decoration was sometimes influenced by Western motifs. The textile industry modernized rapidly and silk from Tokyo's factories became Japan's principal export. Cheap synthetic dyes meant that bold purples and reds, previously restricted to the wealthy elite, could be owned by anyone. Faster and cheaper manufacture allowed more people to afford silk kimono, and enabled designers to create new patterns. The Emperor issued a proclamation promoting Western dress over the allegedly effeminate Japanese dress. Fukuzawa Yukichi's descriptions of Western clothing and customs were influential. Western dress became popular in the public sphere: many men adopted Western dress in the workplace, although kimono were still the norm for men at home and for women. In the 1890s the kimono reasserted itself, with people wearing bolder and brighter styles. A new type called the hōmongi bridged the gap between formal dress and everyday dress. The technology of the time allowed for subtle color gradients rather than abrupt changes of color. Another trend was for outer and inner garments of the same design. Another trend in the Meiji era was for women's under-kimono made by combining pieces of different fabric, sometimes of radically different colors and designs. For men, the trend was for highly decorative under-kimono that would be covered by outer kimono that were plain or very simply designed.
The conversion of testosterone into estradiol by aromatase in many tissues may be an important step in masculinization of that tissue. Masculinization of the brain is thought to occur both by conversion of testosterone into estradiol by aromatase, but also by de novo synthesis of estrogens within the brain. Thus, AFP may protect the fetus from maternal estradiol that would otherwise have a masculinizing effect on the fetus, but its exact role is still controversial.
Russell indexes are a family of global stock market indices from FTSE Russell that allow investors to track the performance of distinct market segments worldwide. Many investors use mutual funds or exchange-traded funds based on the FTSE Russell Indexes as a way of gaining exposure to certain portions of the U.S. stock market. Additionally, many investment managers use the Russell Indexes as benchmarks to measure their own performance. Russell's index design has led to more assets benchmarked to its U.S. index family than all other U.S. equity indexes combined. The best-known index of the series is the Russell 2000, which tracks US small-cap stocks and is made up of the bottom 2,000 stocks in the Russell 3000 index.
== Interactions == Gelsolin is a cytoplasmic, calcium-regulated, actin-modulating protein that binds to the barbed ends of actin filaments, preventing monomer exchange (end-blocking or capping). It can promote nucleation (the assembly of monomers into filaments), as well as sever existing filaments. In addition, this protein binds with high affinity to fibronectin. Plasma gelsolin and cytoplasmic gelsolin are derived from a single gene by alternate initiation sites and differential splicing. Gelsolin has been shown to interact with:
Sources: en.wikipedia.org
=== Food safety === In 2003, the Codex Alimentarius removed any upper dose limit for food irradiation as well as clearances for specific foods, declaring that all are safe to irradiate. Countries such as Pakistan and Brazil have adopted the Codex without any reservation or restriction. Standards that describe calibration and operation for radiation dosimetry, as well as procedures to relate the measured dose to the effects achieved and to report and document such results, are maintained by the American Society for Testing and Materials (ASTM international) and are also available as ISO/ASTM standards. All of the rules involved in processing food are applied to all foods before they are irradiated.
Calcium carbonate is poorly soluble in pure water (47 mg/L at normal atmospheric CO2 partial pressure as shown below). The equilibrium of its solution is given by the equation (with dissolved calcium carbonate on the right):
Many American doctors of the early 20th century studied medicine in Germany and introduced this medical field to the United States, adopting the name "internal medicine" in imitation of the existing German term. Internal medicine has historical roots in ancient India and ancient China. The earliest texts about internal medicine can be found in the Ayurvedic anthologies of Charaka.
The oligonucleotide chain assembly starts with the coupling of a phosphoramidite building block respective to the nucleotide residue second from the 3'-terminus. The 3'-terminal hydroxy group in oligonucleotides synthesized on nucleosidic solid supports is deprotected under the conditions somewhat milder than those applicable for universal solid supports. However, the fact that a nucleosidic solid support has to be selected in a sequence-specific manner reduces the throughput of the entire synthetic process and increases the likelihood of human error. Special solid supports are used for the attachment of desired functional or reporter groups at the 3'-terminus of synthetic oligonucleotides. For example, the commercial solid support 4 allows the preparation of oligonucleotides bearing 3'-terminal 3-aminopropyl linker. Similarly to non-nucleosidic phosphoramidites, many other special solid supports designed for the attachment of reactive functional groups, non-radioactive reporter groups, and terminal modifiers (e.c. cholesterol or other hydrophobic tethers) and suited for various applications are commercially available. A more detailed information on various solid supports for oligonucleotide synthesis can be found in a recent review.
== Tissue distribution == COL21A1 is expressed in a broad range of tissues, including skin, trachea, testis, uterus, placenta, lymph node, stomach and the walls of blood vessels, generally overlapping the distribution of type I collagen. Among these, relative expression is highest in lymph node, jejunum, pancreas, stomach, trachea, testis, uterus and placenta; moderate levels are found in brain, colon, lung, prostate, spinal cord, salivary gland and vascular smooth-muscle cells; and expression is weak in heart, liver, kidney, bone marrow, spleen and thymus. COL21A1 expression is developmentally regulated, being higher at fetal stages than in the corresponding adult tissues. In a comparison of matched human tissues, COL21A1 transcripts were approximately 2.7-, 22- and 30-fold more abundant in fetal brain, heart and liver, respectively, than in their adult counterparts, suggesting a role in developmental processes. In cultured aortic smooth-muscle cells, expression of COL21A1 is stimulated by platelet-derived growth factor (PDGF). Its presence in the walls of blood vessels, where it is produced by smooth-muscle cells, was noted in the original characterization of the gene. Type XXI collagen is also expressed in human skin, where it is a low-abundance component of the dermal extracellular matrix, as detected by quantitative proteomics of healthy skin. In a time-resolved proteomic atlas of the developing skin dermis, type XXI collagen was among the fibril-associated collagens whose abundance declined progressively with age over the human lifespan.
Sources: en.wikipedia.org
Vaginal health can be assessed during a pelvic examination, along with the health of most of the organs of the female reproductive system. Such exams may include the Pap test (or cervical smear). In the United States, Pap test screening is recommended starting around 21 years of age until the age of 65. However, other countries do not recommend pap testing in non-sexually active women. Guidelines on frequency vary from every three to five years. Routine pelvic examination on women who are not pregnant and lack symptoms may be more harmful than beneficial. A normal finding during the pelvic exam of a pregnant woman is a bluish tinge to the vaginal wall. Pelvic exams are most often performed when there are unexplained symptoms of discharge, pain, unexpected bleeding or urinary problems. During a pelvic exam, the vaginal opening is assessed for position, symmetry, presence of the hymen, and shape. The vagina is assessed internally by the examiner with gloved fingers, before the speculum is inserted, to note the presence of any weakness, lumps or nodules. Inflammation and discharge are noted if present. During this time, the Skene's and Bartolin's glands are palpated to identify abnormalities in these structures. After the digital examination of the vagina is complete, the speculum, an instrument to visualize internal structures, is carefully inserted to make the cervix visible. Examination of the vagina may also be done during a cavity search. Lacerations or other injuries to the vagina can occur during sexual assault or other sexual abuse.
=== Full-thickness tissue engineered oral mucosa === With the advancement of tissue engineering an alternative approach was developed: the full-thickness engineered oral mucosa. Full-thickness engineered oral mucosa is a better simulation of the in vivo situation because they take the anatomical structure of native oral mucosa into account. Problems, such as tissue shortage and donor site morbidity, do not occur when using full-thickness engineered oral mucosa. The main goal when producing full-thickness engineered oral mucosa is to make it resemble normal oral mucosa as much as possible. This is achieved by using a combination of different cell types and scaffolds.
Describing the town's atmosphere as "oppressive", he noted that the level's incidental details, such as bodies and gore, told a "powerful story", saying that it was "hard not to feel sorry" for the unwillingly transformed zombies. Polygon writer Jenna Stoeber called Ravenholm an example of Valve's best level design techniques, praising its strong core narrative idea and the fact that the player comes across the level in medias res. USgamer journalist Jeremy Parish stated that Ravenholm "makes great use of audio cues to build tension", noting how the player can hear poison headcrabs before they see them.
On the same day, the talks between the US and Iran—the highest-level discussions between the two since the 1979 Islamic Revolution—were held in Islamabad, Pakistan, lasting 21 hours. JD Vance announced no agreement was reached and Iran had refused "to accept our terms". Trump stated he no longer cared about negotiations. Trump declared that the US Navy would begin its blockade of "all Ships trying to enter, or leave, the Strait of Hormuz" from 13 April. He said the US Navy would stop any ships that paid tolls to Iran. However, United States Central Command clarified that the blockade would only be enforced on ships traveling to or from Iranian ports. The IRGC Navy said any military vessel approaching the strait would be considered a ceasefire violation and meet a "severe response." Trump threatened to strike fast-attack ships of the IRGC Navy, similar to US strikes on drug traffickers during Operation Southern Spear. Iran had 13 days of oil storage capacity, forcing it to shut down its oil fields and potentially damaging them. An analyst estimated loss of import and export capacity would be US$435 million per day. On 16 April, Trump announced that Israel and Lebanon agreed to a ten-day truce. Iran announced that passage of commercial vessels through the strait would be allowed during the truce, however, Trump said that the blockade would continue, with Iran reimposing restrictions on the strait. The US stated that its blockade had intercepted 23 ships. Despite Iran's seizure of two cargo ships, Trump claimed total control over the strait.
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.
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.