The short version of counter-ion fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2025-08-12. Anything still debated is marked as such rather than presented as settled.
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 a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It was derived from the ACTH(4-10) fragment, a short segment of adrenocorticotropic hormone that lacks the hormonal activity associated with the full-length peptide. Researchers at the Institute of Molecular Genetics in Moscow developed the compound during the 1980s. It has been registered as a pharmaceutical product in Russia and several neighbouring countries, where it is supplied as a nasal solution, and it is also sold internationally as a research chemical.
Claims about enhanced focus, memory, or mood in healthy people rest mostly on anecdotal reports and community discussion rather than on controlled data. It remains unclear whether any cognitive benefit observed in patients recovering from brain injury would extend to uninjured users. Dose-response relationships, long-term safety, and interactions with other drugs are not well characterized in the peer-reviewed literature. Questions about optimal route of administration and treatment duration likewise remain open.
Semax binds to melanocortin receptors and is thought to influence neuronal survival and plasticity rather than to act through the adrenal axis. Laboratory work has shown increased expression of brain-derived neurotrophic factor and nerve growth factor in treated tissue. Changes in c-Fos, a marker of neuronal activation, have also been reported. Because the peptide is rapidly degraded by peptidases, its effects are generally attributed to downstream signaling cascades rather than to sustained receptor occupancy.
Published studies are dominated by animal models of stroke, ischemia, and cognitive impairment, with a smaller number of human trials conducted in Russia. Many of the human reports are small, single-center, and published in Russian-language journals, which limits independent scrutiny. Outcome measures vary between studies and often rely on clinician-rated scales rather than objective biomarkers. Systematic reviews have noted the methodological weaknesses and called for larger, preregistered trials before firm conclusions can be drawn.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Calculated for the free peptide |
| Molar mass | 813.9 g/mol | Anhydrous free base |
| Peptide class | Synthetic heptapeptide | ACTH(4-10) analogue |
| Parent fragment | ACTH(4-10) | Adrenocorticotropic hormone segment |
| Developmental origin | Institute of Molecular Genetics, Moscow | Work began in the 1980s |
该化合物于二十世纪八十年代在俄罗斯被开发，相关工作由俄罗斯科学院分子遗传学研究所的研究团队主导。开发目标并非复制 ACTH 的完整激素活性，而是寻找保留其神经作用方向、同时去除促肾上腺皮质激素释放效应的短肽片段。研究记录显示，这一方向促成了多个相关短肽的合成与筛选，而 Semax 是其中被研究最广泛的一个。当地文献常以 Семакс 这一名称指代它。
研究兴趣主要集中在神经营养因子相关的路径上，包括脑源性神经营养因子与神经生长因子的表达变化。部分实验报告称在特定条件下观察到这些因子的水平上升，但具体信号通路和剂量依赖关系仍未完全厘清。多数公开数据来自细胞模型和动物实验，人体对照研究数量有限。因此，该化合物的作用机制在文献中属于活跃讨论，而非已经确立的定论。
Semax 是一种人工合成的七肽，氨基酸序列为 Met-Glu-His-Phe-Pro-Gly-Pro，单字母缩写记作 MEHFPGP。它被归类为促肾上腺皮质激素片段 ACTH(4-10) 的结构类似物，但并不天然存在于生物体内。母体片段 ACTH(4-10) 的序列为 Met-Glu-His-Phe-Arg-Trp-Gly，Semax 替换了中间两个残基，并在羧基端延长了 Pro-Gly-Pro 三肽。这种延长被普遍认为能提升分子对肽酶的耐受性。
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.
Lyophilized material is chemically stable for extended periods when kept dry, cold, and protected from light. The powder is hygroscopic, so vials should be warmed to room temperature before opening to reduce condensation on the contents. Once dissolved, the peptide is far less stable because peptide bonds are susceptible to hydrolysis and the methionine residue can oxidize. Solutions are typically aliquoted and held at 2-8 °C for short intervals or frozen for longer ones, and repeated freeze-thaw cycles should be avoided.
Clinical evidence consists largely of small trials with modest sample sizes, often without independent replication. Reported endpoints include cognitive scores, recovery after stroke, and visual function, but study designs vary widely and few trials meet contemporary reporting standards. Systematic reviewers have noted a high risk of bias in several of these reports. No large multicenter trial conducted outside Russia has been published. The compound is therefore best described as investigational in most jurisdictions, with its clinical role still unresolved.
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.
=== Cell layers === Transitional epithelium is made up of three types of cell layers: basal, intermediate, and superficial. The basal layer fosters the epithelial stem cells in order to provide constant renewal of the epithelium, and each basal cell contacts the basement membrane. These cells' cytoplasm is rich in tonofilaments and mitochondria; however, they contain few rough endoplasmic reticulum. The tonofilaments play a role in the attachment of the basal layer to the basement membrane via desmosomes. The intermediate cell layer is highly proliferative and, therefore, provides for rapid cell regeneration in response to injury or infection of the organ or tube in which it resides. These cells contain a prominent Golgi apparatus and an array of membrane-bound vesicles. These function in the packaging and transport of proteins, such as keratin, to the superficial cell layer. The cells of the superficial cell layer that lines the lumen are known as facet cells or umbrella cells. This layer is the only fully differentiated layer of the epithelium. It provides an impenetrable barrier between the lumen and the bloodstream, so as not to allow the bloodstream to reabsorb harmful wastes or pathogens. All transitional epithelial cells are covered in microvilli and a fibrillar mucous coat. The epithelium contains many intimate and delicate connections to neural and connective tissue. These connections allow for communication to tell the cells to expand or contract.
=== Drugs === Chlorphenamine, a first-generation alkylamine antihistamine Creatine phosphate, a chemical used to store phosphates in the body Cyclophosphamide, a medication to suppress the immune system
Vestiges of British ties were removed piecemeal by the government over the decade following UDI, and replaced with symbols and terminology intended to be more uniquely Rhodesian. A silver "Liberty Bell", based on the bell of the same name in Philadelphia, was cast during 1966 and rung by the Prime Minister 12 times each year on Independence Day (the anniversary of UDI), with some in the press erroneously believing the number of chimes signifying the number of years since the declaration of independence. The Union Jack and Rhodesia's Commonwealth-style national flag—a defaced Sky Blue Ensign with the Union Jack in the canton—continued to fly over government buildings, military bases and other official locations until 11 November 1968, the third anniversary of UDI, when they were superseded by a new national flag: a green-white-green vertical triband, charged centrally with the Rhodesian coat of arms. The Union Jack continued to be ceremonially raised at Cecil Square in Salisbury on 12 September each year as part of the Pioneers' Day holiday, which marked the anniversary of the establishment of Salisbury (and, by extension, Rhodesia) in 1890. Since Elizabeth II was still the Rhodesian head of state in the eyes of Smith's administration until 1970, "God Save the Queen" remained the Rhodesian national anthem, and continued to accompany official occasions such as the opening of the Rhodesian parliament.
=== Infants === In neonates (newborn infants), brown fat makes up about 5% of the body mass and is located on the back, along the upper half of the spine and toward the shoulders. It is of great importance to avoid hypothermia, as lethal cold is a major death risk for premature neonates. Numerous factors make infants more susceptible to cold than adults:
== Abiogenic (opposite) == An abiogenic substance or process does not result from the present or past activity of living organisms. Abiogenic products may, e.g., be minerals, other inorganic compounds, as well as simple organic compounds (e.g. extraterrestrial methane, see also abiogenesis).
Sources: en.wikipedia.org
9 September South Vietnamese officials reported that nearly 5,000 South Vietnamese civilians have been killed by PAVN/VC terror during 1969. Funeral services for Ho Chi Minh were held in Ba Đình Square, Hanoi attended by more than 250,000 mourners. Foreign dignitaries in attendance included Alexei Kosygin, Premier of the Soviet Union, Li Xiannian, Vice Premier of China, Gustáv Husák, General Secretary of the Communist Party of Czechoslovakia, Ignacy Loga-Sowiński, Deputy Premier of Poland, Ion Gheorghe Maurer, Prime Minister of Romania, Sihanouk and Souvanna Phouma.
=== Lysosomal storage disorders === Lysosomal storage disorders are not included in newborn screening programs with high frequency. As a group, they are heterogenous, with screening only being feasible for a small fraction of the approximately 40 identified disorders. The arguments for their inclusion in newborn screening programs center around the advantage of early treatment (when treatment is available), avoiding a diagnostic odyssey for families and providing information for family planning to couples who have an affected child. The arguments against including these disorders, as a group or individually center around the difficulties with reliably identifying individuals who will be affected with a severe form of the disorder, the relatively unproven nature of the treatment methods, and the high cost / high risk associated with some treatment options. New York State started a pilot study to screen for Krabbe disease in 2006, largely due to the efforts of Jim Kelly, whose son, Hunter, was affected with the disease. A pilot screening program for four lysosomal storage diseases (Gaucher disease, Pompe disease, Fabry disease and Niemann-Pick disease was undertaken using anonymised dried blood spots was completed in Austria in 2010. Their data showed an increased incidence from what was expected in the population, and also a number of late onset forms of disease, which are not typically the target for newborn screening programs.
==== Adverse effects ==== The most common adverse effects of nabilone include drowsiness, dizziness, dry mouth, euphoria, concentration difficulties, ataxia, and headache. It has the potential to affect the central nervous system, resulting in anxiety, disorientation, depression, hallucinations and psychosis. Moreover, it may lead to cardiovascular side effects such as orthostatic hypotension and tachycardia. Gastrointestinal adverse reactions also include anorexia, constipation, nausea, vomiting, and oral paresthesia (sensation of tingling in the mouth).
Remogliflozin etabonate (INN/USAN) is a drug of the gliflozin class for the treatment of non-alcoholic steatohepatitis ("NASH") and type 2 diabetes. Remogliflozin was discovered by the Japanese company Kissei Pharmaceutical and is currently being developed by BHV Pharma, a wholly owned subsidiary of North Carolina, US-based Avolynt, and Glenmark Pharmaceuticals through a collaboration with BHV. In 2002, GlaxoSmithKline (GSK) received a license to use it. From 2002 to 2009, GSK carried out a significant clinical development program for the treatment of type-2 diabetes mellitus in various nations across the world and obesity in the UK. Remogliflozin etabonate's pharmacokinetics, pharmacodynamics, and clinical dose regimens were characterized in 18 Phase I and 2 Phase II investigations. Due to financial concerns, GSK stopped working on remogliflozin and sergliflozin, two further SGLT2 inhibitors that were licensed to the company, in 2009. Remogliflozin was commercially launched first in India by Glenmark in May 2019.
Sources: en.wikipedia.org
As a precaution, patients undergoing permanent brachytherapy are advised not to hold small children immediately after treatment and not to be in the vicinity of pregnant women, since low-dose radioactive sources (seeds) remain in the body after treatment with permanent brachytherapy. This is to protect the particularly radiation-sensitive tissues of a fetus or infant.
Parmotrema perlatum is globally widespread lichen found on all continents except Antarctica and predominantly in oceanic areas in Europe, primarily grows on bark and occasionally on siliceous rocks amongst mosses. While it is seeing an increase in the Netherlands due to global warming, it is critically endangered in the Czech Republic, Slovakia, and Poland due to susceptibility to air pollution, and is listed as extinct in certain regional Red Data Books due to a lack of recent findings. In contrast, it has been increasing in sightings in the Netherlands, a phenomenon attributed to both global warming decreases in the levels or air pollution in recent decades. Its recent recurrence in Hungary, particularly on some unusual hosts (Catalpa bignonioides, Prunus serotina, and Robinia pseudoacacia) have been suggested as a possible consequence of "a recolonisation process, due to the improving air quality".
Exon skipping is induced by eteplirsen, a charge-neutral, phosphorodiamidate morpholino oligomer (PMO) that selectively binds to exon 51 of dystrophin pre-mRNA, restoring the phase of the reading frame and enabling production of functional, but internally edited, dystrophin. The uncharged nature of the PMO helps make it resistant to biological degradation. This modified dystrophin protein produced by eteplirsen may cause a less severe form of dystrophinopathy, much like Becker muscular dystrophy. Eteplirsen's proposed mechanism of action is to bind to dystrophin pre-mRNA and alter the exon splicing of the RNA so that more almost full-length dystrophin is made. By increasing the quantity of an abnormal, but potentially functional, dystrophin protein, the objective is to slow or prevent the progression of DMD.
Wadden, Thomas A.; Chao, Ariana M.; Machineni, Sriram; Kushner, Robert; Ard, Jamy; Srivastava, Gitanjali; Halpern, Bruno; Zhang, Shuyu; Chen, Jiaxun; Bunck, Mathijs C.; Ahmad, Nadia N.; Forrester, Tammy (2023). "Tirzepatide after intensive lifestyle intervention in adults with overweight or obesity: The SURMOUNT-3 phase 3 trial". Nature Medicine. 29 (11): 2909–2918. doi:10.1038/s41591-023-02597-w. PMC 10667099. PMID 37840095. Wadden, Thomas A.; Chao, Ariana M.; Moore, Molly; Tronieri, Jena S.; Gilden, Adam; Amaro, Anastassia; Leonard, Sharon; Jakicic, John M. (2023). "The Role of Lifestyle Modification with Second-Generation Anti-obesity Medications: Comparisons, Questions, and Clinical Opportunities". Current Obesity Reports. 12 (4): 453–473. doi:10.1007/s13679-023-00534-z. PMC 10748770. PMID 38041774. Wadden, Thomas A.; Brown, Gregory K.; Egebjerg, Christina; Frenkel, Ofir; Goldman, Bryan; Kushner, Robert F.; McGowan, Barbara; Overvad, Maria; Fink-Jensen, Anders (2024). "Psychiatric Safety of Semaglutide for Weight Management in People Without Known Major Psychopathology". JAMA Internal Medicine. 184 (11): 1290–1300. doi:10.1001/jamainternmed.2024.4346. PMC 11372653. PMID 39226070.
== V == Vagus nerve Cranial nerve X, responsible for parasympathetic control of the heart, lungs, and digestive tract. It also conveys sensory information from the viscera to the brainstem. Vasopressin Also known as antidiuretic hormone (ADH), it regulates water balance and blood pressure. In the brain, vasopressin influences social behavior and memory. Ventral A directional term meaning "toward the front" in the spinal cord or "toward the bottom" in the brain. Opposite of dorsal. Ventral horn The anterior portion of the spinal cord’s gray matter, containing motor neurons that project to skeletal muscles. Ventral stream A visual processing pathway ("what" pathway) that travels from the occipital lobe to the temporal lobe and is involved in object recognition and form representation. Ventral tegmental area (VTA) A midbrain structure containing dopaminergic neurons that project to the nucleus accumbens and prefrontal cortex, central to reward and motivation. Ventricles A set of interconnected cavities in the brain filled with cerebrospinal fluid (CSF), which cushions the brain and maintains intracranial pressure. Vestibular system The sensory system that contributes to balance, spatial orientation, and coordination of head and eye movements. Includes the semicircular canals and otolith organs. Vestibulo-ocular reflex (VOR) A reflex that stabilizes vision by producing eye movements in the opposite direction of head movement, allowing steady gaze.
Sources: en.wikipedia.org
Semax is based on the ACTH(4-10) fragment, a seven-amino-acid segment of adrenocorticotropic hormone. The synthetic peptide retains the core sequence while removing regions associated with endocrine activity. This modification is intended to isolate effects on the nervous system.
It is registered for clinical use in Russia and a few other countries, typically as a nasal drop formulation. It does not hold approval from the United States Food and Drug Administration or the European Medicines Agency. Outside those markets it is generally handled as a research chemical.
The compound was developed in Moscow and the earliest studies were conducted there, so the primary literature is largely in Russian-language journals. Translation and indexing have been incomplete, which limits access for outside researchers. Independent groups have since published some work, but the total volume remains modest.
It is associated with the melanocortin receptor family, particularly subtypes found in the central nervous system. This interaction is separate from the adrenal pathway activated by full-length ACTH.