If you have been reading about counterion 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 2026-01-13. Numbers and descriptions here follow the published literature rather than marketing material.
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.
Common degradation pathways include oxidation of the methionine side chain, hydrolysis of the peptide backbone, and aggregation under unfavourable pH or concentration. Stability studies typically monitor the main peak by chromatography and report total related substances as a percentage. Because no official monograph exists, acceptance criteria vary between laboratories, and reported purity values are not directly comparable across suppliers. Analysts therefore document the method, column, and detection wavelength alongside each result, and open questions remain about how much biological activity the oxidised forms retain.
Solid semax is typically supplied as a lyophilised powder that is hygroscopic and sensitive to moisture, light, and repeated temperature cycling. Long-term storage of the dry peptide is generally recommended at approximately -20 degrees Celsius, while shorter working periods may use refrigeration at 2 to 8 degrees Celsius. Vials should remain tightly closed and desiccated when brought to room temperature, because condensation can damage the material before it is weighed. Dividing a batch into aliquots is preferable to thawing one container repeatedly.
| Property | Value | Notes |
|---|---|---|
| Primary research models | Rodent studies | Largest share of published data |
| Reported markers | BDNF and NGF expression | Measured mainly in animal tissue |
| Common administration | Intranasal | Matches the registered formulation |
| Blood residence time | Minutes | Rapid enzymatic degradation |
| Evidence quality | Small trials, limited replication | Noted repeatedly in reviews |
Practical handling follows from those properties. Bulk material is best divided into single-use portions soon after receipt, because each thaw exposes the whole container to moisture and temperature cycling. Vials should be allowed to reach room temperature before opening to prevent condensation on the powder. Low-binding plasticware reduces loss of dilute solutions, and sterile filtration is used when a preparation must remain free of microbial growth. Records of batch number, reconstitution date and storage history are what allow a later analytical result to be interpreted meaningfully.
Identity and purity of Semax are established mainly by reversed-phase high-performance liquid chromatography coupled with mass spectrometry. The chromatographic trace gives a purity estimate as a percentage of total peak area, while electrospray or matrix-assisted laser desorption ionization confirms the molecular mass against the calculated value. Amino acid analysis and sequence-specific fragmentation provide further confirmation when a supplier's chain of custody is unclear. Vendors frequently quote a purity figure without stating the detection wavelength or the integration method, which limits how far one number can be compared with another.
Stability depends heavily on physical state. Lyophilized powder held dry, cold and dark retains its content over long periods, whereas dissolved peptide begins to change within days at room temperature. The most cited degradation route is oxidation of the methionine residue, which converts the peptide to a sulfoxide form that elutes differently on chromatography. Hydrolysis of amide bonds and adsorption onto container walls contribute smaller losses. Buffers that exclude oxygen from the headspace slow the oxidation pathway, but no single condition prevents all change indefinitely.
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.
Semax is supplied as a lyophilized powder that appears white to off-white. It dissolves readily in water, phosphate-buffered saline, and other aqueous media, which simplifies preparation of working solutions for laboratory use. The nasal products registered in Russia are dilute aqueous solutions, typically around 0.1 percent peptide by weight. Organic solvents are rarely necessary and can complicate handling. Because the peptide is hygroscopic, weighing should be performed quickly and with minimal exposure to ambient humidity.
Solid material is normally kept at minus 20 degrees Celsius in a sealed, desiccated container. Reconstituted solutions are less stable and are usually divided into single-use aliquots before freezing. Repeated freeze-thaw cycles are avoided because they promote aggregation and loss of activity. Light exposure is minimized by using amber glassware or foil wrapping. Published stability data for this peptide are sparse, so recommended storage conditions rest mainly on general practice for short synthetic peptides rather than on dedicated study.
== Production == Most 131I production is from neutron irradiation of a natural tellurium target in a nuclear reactor. Irradiation of natural tellurium produces almost entirely 131I as the only radionuclide with a half-life longer than hours (and shorter than millions of years), since lighter isotopes of tellurium become heavier stable isotopes, or else stable antimony or iodine. However, the heaviest naturally occurring tellurium nuclide, 130Te (34% of natural tellurium) absorbs a neutron to become tellurium-131, which beta decays with a half-life of 25 minutes to 131I. A tellurium compound can be irradiated while bound as an oxide to an ion exchange column, with evolved 131I then eluted into an alkaline solution. More commonly, powdered elemental tellurium is irradiated and then 131I separated from it by dry distillation of the iodine, which has a far higher vapor pressure. The element is then dissolved in a mildly alkaline solution in the standard manner, to produce 131I as iodide and hypoiodate (which is soon reduced to iodide). 131I is a fission product with a yield of 2.878% from uranium-235, and can be released in nuclear weapons tests and nuclear accidents. However, the short half-life means it is not present in significant quantities in cooled spent nuclear fuel, unlike iodine-129 whose half-life is nearly a billion times that of 131I. It is discharged to the atmosphere in small quantities by some nuclear power plants.
The Mareth Line constituted one of two fronts in the Tunisia Campaign, the second being to the north-west, where the British First Army and American II Corps, firmly established in formerly Vichy-held Morocco and Algeria following Operation Torch in November 1942, were gradually pushing the Axis forces under Hans-Jürgen von Arnim back towards Tunis. After von Arnim won a decisive victory over the Americans at the Battle of Sidi Bou Zid in mid-February 1943, destroying over 100 US tanks, the Eighteenth Army Group was formed under the British General Harold Alexander to co-ordinate the actions of the Allied forces on both Tunisian fronts. The Eighth Army under Montgomery spent February at Medinine in south-eastern Tunisia. Expecting an imminent attack by the Axis, the Eighth Army mustered every anti-tank gun it could from Egypt and Libya. The 102nd (Northumberland Hussars) Anti-Tank Regiment, including the Rhodesian Anti-Tank Battery under Major Savory, duly advanced west from Benghazi and reached the front on 5 March 1943. The Germans and Italians assaulted Medinine the next day, but failed to make much progress and abandoned their attack by the evening. The Rhodesian gunners, held in reserve, did not take part in the engagement but were attacked from the air. The Rhodesians of the KRRC, now under the 7th Motor Brigade, moved up from Libya during early March. No. 237 (Rhodesia) Squadron, which had spent 1942 and the first months of 1943 in Iran and Iraq, returned to North Africa the same month, with the future Prime Minister Ian Smith in its ranks as a Hurricane pilot.
== Structure == The chordae tendineae connect the atrioventricular valves (tricuspid and mitral), to the papillary muscles within the ventricles. Multiple chordae tendineae attach to each leaflet or cusp of the valves. Chordae tendineae contain elastin in a delicate structure notably at their periphery.
Inducers of hepatic microsomal enzymes such as barbiturates, phenytoin, and rifampicin can reduce the half-life of dexamethasone. Cotreatment with oral contraceptives can increase its volume of distribution.
(1978), federal judge of the United States District Court for the District of New Jersey Rolando Acosta (1979), associate justice of the Appellate Division of the New York Supreme Court, First Judicial Department Frank J. Aquila (1979), corporate lawyer, partner at Sullivan & Cromwell Umar Ata Bandial (1979), justice of the Supreme Court of Pakistan and former chief justice of Lahore High Court Lanny A. Breuer (1980), U.S. assistant attorney general for the Criminal Division Ronald Weich (1980), U.S. assistant attorney general for the Office of Legislative Affairs Paul Feinman (1981), judge of the New York Court of Appeals Michael H. Cohen (1983), healthcare law attorney, professor at Harvard Medical School Miguel Estrada (1983), controversial nominee to the United States Court of Appeals for the D.C. Circuit Steven Reich (1983), CEO of Deutsche Bank Trust Company and former associate deputy attorney general 2011–2013 Gary R. Brown (1985), judge of the United States District Court for the Eastern District of New York John H. Chun (1991), judge and nominee to the United States District Court for the Western District of Washington Andrew Ceresney (1993), chair of litigation practice at Debevoise & Plimpton and former head of enforcement at the U.S. Securities and Exchange Commission Veronica S.
Sources: en.wikipedia.org
== Epidemiology == Chronic wounds mostly affect people over the age of 60. The incidence is 0.78% of the population and the prevalence ranges from 0.18 to 0.32%. As the population ages, the number of chronic wounds is expected to rise. Ulcers that heal within 12 weeks are usually classified as acute, and longer-lasting ones as chronic.
The establishment is a modern, structured research institute composed of six laboratories dedicated to Virology, Parasitology, Bacteriology, Medical Entomology, Clinical Biology and Pathology, including a Research Center for animals and a data center. Each laboratory is made up of a dedicated director and staff, including students and international collaborators. Each laboratory has the basic equipment and the space necessary for optimal research. It is available to faculty, students, post-docs and staff from the periphery of the INRB. Due to the structure of the INRB, if sharing and access to individual laboratory equipment is required, access is granted at the request and approval of the directors of these laboratories. The INRB common area includes some major equipment. All collaborators and researchers have, upon request, access to several -80 freezers, liquid nitrogen tanks, centrifuges, water baths, tissue homogenizers, vortexes, incubators, agitators, and all laboratories have access to cold chain equipment such as dry shippers and portable freezers. The INRB was founded in 1984 and has been a World Health Organization collaborating centre since 2018. The INRB and the World Health Organization have worked closely together on research into the effectiveness of the ring vaccination strategy during the 2018 Kivu Ebola outbreak. The National Biomedical Research Institute (INRB) has eight dynamic departments, which participate in the institute's various missions, namely monitoring, research, and training.
== History == The consumption of wheatgrass in the Western world began in the 1930s as a result of experiments conducted by Charles Schnabel in his attempts to popularize the plant. By 1940, cans of Schnabel's powdered grass were on sale in major drug stores throughout the United States and Canada. Ann Wigmore was also a strong advocate for the consumption of wheatgrass as a part of a raw food diet. Wigmore, founder of the Hippocrates Health Institute, believed that wheatgrass, as a part of a raw food diet, would cleanse the body of toxins while providing a proper balance of nutrients as a whole food. She also taught that wheatgrass could be used to treat those with serious disease. Both of these claims are believed by many reputable health institutes to be entirely unfounded by facts, and possibly dangerous.
== June 4, 1915 (Friday) == Third Battle of Krithia — British, French, and Indian forces made a third and last attempt to capture Achi Baba, the main position for Ottoman defenses on the Gallipoli peninsula but were beaten back, sustaining some 6,500 casualties. Ottoman casualties were higher, ranging between 9,000 and 10,000 men. The LZ 40, the first Zeppelin P Class airship of the Imperial German Navy, was flown to bomb targets in London. The Royal Norwegian Navy Air Service test flew the M.F.1 floatplane in Horten, Norway, the first Marinens Flyvebaatfabrikk model based on a design by Maurice Farman. The fraternity Alpha Sigma Nu was founded at Marquette University as an honor society for Jesuit colleges. Born: Modibo Keïta, Malian statesman, first President of Mali; in Bamako Coura, French Sudan (present-day Bamako, Mali) (d. 1977) Walter Hadlee, New Zealand cricketer, batman for the New Zealand national cricket team from 1937 to 1951; in Lincoln, New Zealand (d. 2006)
thymidine (T, dT) Also deoxythymidine. One of the four standard nucleosides used in DNA molecules, consisting of a thymine base with its N9 nitrogen bonded to the C1 carbon of a deoxyribose sugar. The prefix deoxy- is commonly omitted, since there are no ribonucleoside analogs of thymidine used in RNA, where it is replaced with uridine instead.
Sources: en.wikipedia.org
=== Hopman Cup === Zverev represented Germany at the Hopman Cup for four consecutive years from 2016 through 2019 with three different partners. In 2016, he competed with Sabine Lisicki. The duo won their tie against the French team, with Zverev winning both his singles and mixed doubles matches. However, they were shut out against Great Britain and Australia Green and did not advance to the final. The following year, he entered the competition with Andrea Petkovic. While the pair only won their tie against Great Britain, Zverev also defeated Federer in singles in his first tournament back from injury. Zverev enjoyed more success in 2018 and 2019, pairing with Angelique Kerber. In their first year together, they advanced to the final, primarily on the strength of the pair winning all three of their mixed doubles matches. In the final against Switzerland, Zverev lost his singles match to Federer. Although Kerber won her singles match against Belinda Bencic, they lost the decisive mixed doubles rubber. They returned in 2019 and again reached the final to set up a rematch of the previous year's final with Federer and Bencic. In a round-robin group with Australia, France, and Spain, the two of them won all six of their singles matches, but lost two of their three mixed doubles matches against Australia and France. Like the previous year, the final was decided by the mixed doubles match after Federer defeated Zverev and Kerber defeated Bencic. With the Fast4 format, the match went to three sets. In the third set tiebreak, both teams had a match point at 4–4.
=== Disorders of mineral metabolism === 275 Disorders of mineral metabolism 275.0 Disorders of iron metabolism Aceruloplasminemia Hemochromatosis 275.1 Disorders of copper metabolism Wilson's disease 275.2 Disorders of magnesium metabolism Hypermagnesemia Hypomagnesemia 275.3 Disorders of phosphorus metabolism Familial hypophosphatemia Hypophosphatasia 275.4 Disorders of calcium metabolism 275.41 Hypocalcemia 275.42 Hypercalcemia 275.49 Pseudohypoparathyroidism
=== Vascular anomalies === A vascular anomaly can be either a vascular tumor or a birthmark, or a vascular malformation. In a tumor such as infantile hemangioma the mass is soft, and easily compressed, and their coloring is due to the dilated anomalous involved veins. They are most commonly found in the head and neck. Venous malformations are the type of vascular malformation that involves the veins. They can often extend deeper from their surface appearance, reaching underlying muscle or bone. In the neck they may extend into the lining of the mouth cavity or into the salivary glands. They are the most common of the vascular malformations. A severe venous malformation can involve the lymph vessels as a lymphaticovenous malformation.
Stanozolol (abbrev. Stz), sold under many brand names, is a synthetic androgen and anabolic steroid (AAS) medication derived from dihydrotestosterone (DHT). It is used to treat hereditary angioedema. It was developed by American pharmaceutical company Sterling-Winthrop in 1962, and has been approved by the U.S. Food and Drug Administration for human use, though it is no longer marketed in the United States. It is also used in veterinary medicine. Stanozolol has mostly been discontinued, and remains available in only a few countries. It is given by mouth in humans or by injection into muscle in animals. Unlike most AAS, stanozolol is not esterified and is sold as an aqueous suspension, or in oral tablet form. The drug has a high oral bioavailability, due to a C17α alkylation which allows the hormone to survive first-pass liver metabolism when ingested. It is because of this that stanozolol is also sold in tablet form. Stanozolol is one of the AAS commonly used as performance-enhancing drugs and is banned from use in sports competition under the auspices of the World Anti-Doping Agency (WADA). It is an anabolic steroid that is known to have a diuretic effect. Additionally, stanozolol has been highly restricted in US horse racing.
Laird announced that the first U.S. forces to leave South Vietnam would be 900 infantrymen from the 9th Infantry Division. Prime Minister of Laos Souvanna Phouma acknowledged that U.S. aircraft regularly carried out bombing missions over Laos.
Sources: en.wikipedia.org
The main proposal is modulation of neurotrophic factors such as brain-derived neurotrophic factor, supported largely by animal experiments. Receptor-level targets have not been firmly established. Most reviews describe the mechanism as only partially characterized.
The compound is registered as a medicine in Russia, so clinical work has concentrated there. Trials elsewhere are few and generally small. This geographic concentration is a recognized limitation in evidence reviews.
Some fraction may reach the central nervous system through olfactory pathways, and this is often cited as the rationale for the nasal route. The size of that fraction in humans is not well quantified. Blood concentrations after nasal dosing are low, which complicates measurement.
Dry powder is usually kept at about -20 degrees Celsius for long-term storage and at 2 to 8 degrees Celsius for short working periods. Containers should stay sealed and protected from light and moisture to limit degradation.