If you have been reading about counter-ion 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.
Updated 2026-06-05. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Typical purity | 95% or higher | By reversed-phase HPLC area |
| Identity method | Electrospray mass spectrometry | Confirms molecular mass |
| Purity method | Reversed-phase HPLC | Detection near 214 nm |
| Primary degradation | Methionine oxidation | Sulfoxide product, +16 Da |
| Solution storage | 2-8 °C, short term | Aliquot to avoid freeze-thaw |
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.
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 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.
Identity and purity are commonly assessed by reversed-phase high-performance liquid chromatography, with ultraviolet detection near 214 nanometers for the peptide backbone. Mass spectrometry, either electrospray or matrix-assisted laser desorption, confirms molecular mass and detects truncation or modification products. Amino acid analysis can verify composition. Because the sequence contains no strongly absorbing aromatic residue apart from phenylalanine, detection wavelengths are chosen carefully. Purity values above 95 percent are typical for research-grade material.
Quality documentation for research-grade peptide usually includes a certificate of analysis stating purity, identity, and residual counterion content. Batch-to-batch variation in purity and salt form is a recognized issue, and comparisons across suppliers require attention to the exact counterion, for example acetate versus trifluoroacetate. Sequence verification by tandem mass spectrometry provides stronger evidence than a single mass measurement. For any study reporting biological results, the analytical method and the measured purity should be stated explicitly. Independent verification of supplier claims is considered good practice.
==== United States ==== The US Food and Drug Administration (FDA) considers safe beverages containing less than 0.02% caffeine; but caffeine powder, which is sold as a dietary supplement, is unregulated. It is a regulatory requirement that the label of most prepackaged foods must declare a list of ingredients, including food additives such as caffeine, in descending order of proportion. However, there is no regulatory provision for mandatory quantitative labeling of caffeine, (e.g., milligrams caffeine per stated serving size). There are a number of food ingredients that naturally contain caffeine. These ingredients must appear in food ingredient lists. However, as is the case for "food additive caffeine", there is no requirement to identify the quantitative amount of caffeine in composite foods containing ingredients that are natural sources of caffeine. While coffee or chocolate are broadly recognized as caffeine sources, some ingredients (e.g., guarana, yerba maté) are likely less recognized as caffeine sources. For these natural sources of caffeine, there is no regulatory provision requiring that a food label identify the presence of caffeine nor state the amount of caffeine present in the food. The FDA guidance was updated in 2018.
Like other SSRIs, escitalopram often exacerbates symptoms of mania and hypomania in individuals misdiagnosed with a depressive disorder instead of a bipolar disorder, making it crucial for clinicians to rule out bipolar disorders before prescribing escitalopram.
== Adverse effects == The US Food and Drug Administration prescribing information contains a boxed warning for embryo-fetal toxicity. The most common adverse reactions include diarrhea, infusion-related reactions, abdominal pain, and fatigue.
In Lima the problem was that the delivery of territories had to be immediate, but not the payment of the debt, which caused the chancellor José María Pando and the President of the Governing Board Andrés de Santa Cruz to reject the treaty. They make it clear that they would hand over Arica or Iquique but only for immediate benefits. As for the federative idea, what was agreed established a very weak executive and legislature that would only generate chaos and make them dependent on Gran Colombia to maintain order, denouncing an anti-Peruvianism of part of Simón Bolívar and Antonio José de Sucre. Looking for alternatives, the Upper Peruvians sent the secret "legislative legation", a commission to ask Bolívar to suspend the decree of May 16, 1825 by which Arica was Peruvian, but they failed, since Bolívar did not want to provoke the people of Lima any more. There is also the anti-Peruvian belief that the War against the Peru-Bolivian Confederation was a Peruvian betrayal of Bolivia due to Bolivian nationalist hoaxes that the opposition of several Peruvians to the Union was motivated by being governed by a Bolivian (Andres de Santa Cruz), and that to avoid it, they ended up allying with Chile to achieve the fall of the confederation.
== Regulatory functions == The HGSA oversees the regulation of the genetic counselling profession throughout Australia and New Zealand. The profession self-regulates under the auspices of the National Alliance of Self-Regulation Health Professions. The HGSA maintains a register of appropriately qualified genetic counsellors, accredits and records their mandatory continuing professional development activities, and provides a mechanism to deal with professional concerns and complaints of genetic counsellors.
Sources: en.wikipedia.org
SSRIs prevent 5-HT from binding to SERT which prevents absorption of 5-HT back into the presynapse terminal, where it is metabolized by monoamine oxidase or stored in secretory vesicles. As a result, the 5-HT concentration increases at the somatodendritic area of the 5-HT neuron but not so much at the axon terminal area (demonstrated in figure 2). This increase in 5-HT concentration causes desensitization of somatodendritic 5-HT1A autoreceptors. When these 5-HT1A autoreceptors have been downregulated, they will no longer restrict the impulse flow of the 5-HT neuron. The impulse flow is turned on and as a result 5-HT is released at the axon terminal. However, this increase of 5-HT does not happen quickly compared to the increase of 5-HT at the somatodendritic area of the 5-HT neuron. This delay is caused by the time it takes 5-HT to downregulate 5-HT1A autoreceptors and turn on the neuro impulse flow of the 5-HT neuron. This delay can explain the reason why antidepressants do not have effect on depression immediately. This can also be the reason why the antidepressant mechanisms can be connected to the increasing neuro impulse flow from 5-HT neurons, where as the concentration of 5-HT increases at the axon terminal before SSRIs start to work properly. When SSRIs have (1) inhibited the re-uptake pump, (2) increased somatodendritic 5-HT, (3) desensitized somatodendritic 5-HT1A autoreceptors, (4) turned on the impulse flow and (5) increased the release of 5-HT from axon terminal, the last step might be desensitization of postsynaptic 5-HT receptors.
Valuable, temperature-sensitive, or hazardous cargo often require the utmost in system reliability. This type of reliability can only be achieved through the installation of a redundant refrigeration system. A redundant refrigeration system consists of integrated primary and back-up refrigeration units. If the primary unit malfunctions, the secondary unit automatically starts. To provide reliable power to the refrigeration units, these containers are often fitted with one or more diesel generator sets. Containers fitted with these systems may be required for transporting certain dangerous goods in order to comply with the International Maritime Organization’s regulations.
== Bibliography == “Inka Hydraulic Engineering”, University of Colorado at Denver. 19 September 2006. Brown, Jeff L. “Water Supply and Drainage Systems at Machu Picchu” 19 September 2006 Wright, Kenneth R. “Machu Picchu: Prehistoric Public Works.” American Public Works Association APWA Reporter, 17 November 2003 [1] Archived 2009-08-31 at the Wayback Machine D’Altroy, Terence N. and Christine A. Hastorf. Empire and Domestic Economy. New York: Kluwer Academic/Plenum Publishers, 2001. Wright, Kenneth, Jonathan M. Kelly, Alfredo Valencia Zegarra. “Machu Pichu: Ancient Hydraulic Engineering”. Journal of Hydraulic Engineering, October 1997. Bauer, Brian. The Development of the Inca State. University of Texas Press, Austin, 1992. Hyslop, John. Inka Settlement Planning. University of Texas Press, Austin, 1990.
== History == In the mid-1950s, the pharmaceutical research department of Ciba AG discovered the (low) analgesic effect of 1-(β-diethylaminoethyl)-2-benzylbenzimidazole (desnitazene). Systematic derivatization of this parent compound in the course of structure-activity relationship investigations revealed an enhancement of activity by nitration of the 5-position. 4'-Methoxylated and ethoxylated compounds achieved potencies in the hot plate test that were previously unattained. The thus discovered etonitazene is the most potent nitazene opioid known to date. The morphine-like mechanism of action was elucidated from the antagonizability of analgesia with allylnormorphine. In a human clinical trial, two nitazenes (etonitazene and clonitazene) were investigated in 363 patients and the results were published in 1958. The early 21st century marked the beginning of the spread of nitazene opioids in the drug scene, and in the early 2020s, the substances were recognized as emerging drugs of abuse. Isotonitazene was first identified in samples of illicit drugs, and it was implicated in opioid overdose deaths in Europe, Canada, and the United States in March and April 2019. Previously known nitazene analogs, such as metonitazene and butonitazene (as well as novel nitazenes not previously described in the scientific or patent literature), have since been discovered in toxicologic samples during forensic investigations. Nitazenes have been found in pills missold as other drugs, such as benzodiazepines, in the United Kingdom and New Zealand.
Arterial embalming, which involves the injection of embalming chemicals into the blood vessels, usually via the right common carotid artery. Blood and interstitial fluids are displaced by this injection and, along with excess arterial solution, are expelled from the right jugular vein and collectively referred to as drainage. The embalming solution is injected with a centrifugal pump, and the embalmer massages the body to break up circulatory clots so as to ensure the proper distribution of the embalming solution. This process of raising vessels with injection and drainage from a solitary location is known as a single-point injection. In cases of poor circulation of the arterial solution, additional injection points (commonly the axillary, brachial, or femoral arteries, with the ulnar, radial, and tibial vessels if necessary) are used. Cases where more than one vessel is raised are referred to as multi-point injection, with a reference to the number of vessels raised (i.e. a six-point injection or six-pointer). As a general rule, the more points needing to be raised, the greater the difficulty of the case. In some cases draining from a different site from injection (i.e. injecting arterial fluid into the right common carotid artery and draining from the right femoral vein) is referred to as a split (or sometimes cut) injection. In certain cases the embalmer may deem it necessary to perform a restricted cervical injection, which involves injecting the head of the deceased separately from the rest of body.
Sources: en.wikipedia.org
The condition known today as diabetes (usually referring to diabetes mellitus) is thought to have been described in the Ebers Papyrus (c. 1550 BC). Ayurvedic physicians (5th/6th century BC) first noted the sweet taste of diabetic urine, and called the condition madhumeha ("honey urine"). The term diabetes traces back to Demetrius of Apamea (1st century BC). For a long time, the condition was described and treated in traditional Chinese medicine as xiāo kě (消渴; "wasting-thirst"). Physicians of the medieval Islamic world, including Avicenna, have also written on diabetes. Early accounts often referred to diabetes as a disease of the kidneys. In 1674, Thomas Willis suggested that diabetes may be a disease of the blood. Johann Peter Frank is credited with distinguishing diabetes mellitus and diabetes insipidus in 1794. In regard to diabetes mellitus, Joseph von Mering and Oskar Minkowski are commonly credited with the formal discovery (1889) of a role for the pancreas in causing the condition. In 1893, Édouard Laguesse suggested that the islet cells of the pancreas, described as "little heaps of cells" by Paul Langerhans in 1869, might play a regulatory role in digestion. These cells were named islets of Langerhans after the original discoverer. In the beginning of the 20th century, physicians hypothesized that the islets secrete a substance (named "insulin") that metabolises carbohydrates. The first to isolate the extract used, called insulin, was Nicolae Paulescu.
Increases cardiac output Increases heart rate Increases ventilation rate Increases basal metabolic rate Potentiates the effects of catecholamines (i.e. increases sympathetic activity) Potentiates brain development Thickens endometrium in females Increases catabolism of proteins and carbohydrates
Dupilumab is indicated for the treatment of moderate-to-severe atopic dermatitis; moderate-to-severe asthma; chronic rhinosinusitis with nasal polyps; eosinophilic esophagitis; prurigo nodularis; and chronic obstructive pulmonary disease. It has been shown to be effective at treating aspirin-exacerbated respiratory disease (AERD), a typically difficult to treat condition where aspirin intolerant patients have both chronic rhinosinusitis with nasal polyps and asthma.
znajneprekryštalizovávateľnejšievajúcimi, 40 letters, "through the least crystallised ones" znajnepreinternacionalizovateľnejšievať, 39 letters najnezrevolucionalizovateľnejšiemu, 34 letters najnerozkrasokorčuľovateľnejšieho, 33 letters Artificial words using Slovak towns or places, lexically valid but never used in language:
Sources: en.wikipedia.org
Dry powder is normally held at -20 °C or lower, away from light and moisture. Sealed vials can also be kept at 2-8 °C for shorter intervals. Warming to room temperature before opening prevents condensation.
In solution, hydrolysis of peptide bonds and oxidation of the methionine residue are the principal concerns. Oxidation converts methionine to its sulfoxide form, shifting the mass by sixteen daltons. Both processes are slowed by cold storage and by avoiding alkaline conditions.
A certificate documents what the supplier measured on a specific lot, not how a laboratory will use the material. Independent verification of identity and purity is common practice. Acceptance criteria should be defined before a batch is ordered.
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.