A practical reference on counter-ion: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2025-10-02. Anything still debated is marked as such rather than presented as settled.
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.
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.
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.
| 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 |
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.
Reported pharmacological work centers on neurotrophic signaling, including changes in BDNF and NGF expression in hippocampal tissue in animal models. Human data come largely from studies conducted in Russia, and how well those results generalize to other populations remains an open question. Regulatory status differs sharply by jurisdiction: Semax is a registered prescription medicine in Russia, while it holds no approved marketing status in the United States or the European Union. Outside such jurisdictions it is generally handled as a research chemical, which affects both documentation and quality expectations.
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.
Published research has focused mainly on neurological and cognitive endpoints in animal models, with proposed mechanisms involving brain-derived neurotrophic factor and related signalling pathways. A substantial share of the human data originates from a limited number of research groups, and independent replication in other countries remains sparse. Regulatory status reflects that distribution: the peptide is registered as a medicine in Russia and appears in some neighbouring markets, while elsewhere it is handled as a research chemical without approved therapeutic labelling. Questions about dose-response relationships, long-term effects, and comparability across studies are still open.
Lyophilised powder is normally kept at -20 °C in a desiccated container, with some suppliers recommending -80 °C for long-term archival storage. Repeated freeze-thaw cycles are the most common cause of avoidable loss, so aliquoting before freezing reduces variability between working sessions. Dissolved peptide is far less stable than the dry solid and is usually prepared fresh or held briefly at 4 °C. Aqueous solutions support both hydrolysis of the backbone and oxidation of the N-terminal methionine, and these two routes dominate degradation under ordinary laboratory conditions.
Identity and purity are confirmed with reversed-phase high-performance liquid chromatography, typically monitored at 214 nanometres where the peptide bond absorbs. Mass spectrometry, either electrospray or MALDI-TOF, verifies molecular mass against the theoretical value and detects truncation or adduct formation. Amino acid analysis and peptide mapping provide additional confirmation when required. The most frequently reported impurities are deletion sequences from incomplete coupling, methionine sulfoxide from oxidation, and dimeric species formed through non-covalent aggregation. Impurity profiles depend strongly on the synthesis and purification route chosen by the producer.
In 1933, Schoenheimer emigrated to the United States, where his scientific research took a different focus. Prior to his emigration, his work was mostly focused on the metabolism of cholesterol. In 1934 Schoenheimer began his work on intermediary metabolism, and how stable isotopes could be applied to the study. Schoenheimer worked alongside David Rittenburg and later Konrad Bloch. Schoenheimer and his colleagues began their research by conducting experiments with the use of deuterium. Deuterium, which is a stable isotope of hydrogen, was discovered by physical chemist Harold Urey in 1932. One of the methods used in the experiment involved heavy water administered into animals in order to analyse the deuterium present in the different constituents of the body. This suggested which type of substances were utilising the hydrogen present in body fluids and revealed the role water posed in metabolic processes. Their experiment also provided information regarding the breakdown process of lipid compounds containing deuterium in experimental animals. Prior to this study, it was assumed that animals utilised fats directly from foods that they had recently ingested, and that fat stores were only used amid starvation. The experiment revealed that fatty acids remained stored in body depots even during starvation. Schoenheimer and his colleagues then began a study of protein metabolism using the isotope of nitrogen as it became available. Schoenheimer and his colleague David Rittenberg, analysed how synthesised amino acids containing nitrogen would operate within an animal's body.
== Detection by mass spectrometry == A mass spectrum of an organic compound will usually contain a small peak of one mass unit greater than the apparent molecular ion peak (M) of the whole molecule. This is known as the M+1 peak and comes from the few molecules that contain a 13C atom in place of a 12C. A molecule containing one carbon atom will be expected to have an M+1 peak of approximately 1.1% of the size of the M peak, as 1.1% of the molecules will have a 13C rather than a 12C. Similarly, a molecule containing two carbon atoms will be expected to have an M+1 peak of approximately 2.2% of the size of the M peak, as there is double the previous likelihood that any molecule will contain a 13C atom. In the above, the mathematics and chemistry have been simplified. However it can be used effectively to give the number of carbon atoms for small- to medium-sized organic molecules. In the following formula, the result should be rounded to the nearest integer:
Canning is a process during which the enzymes in vegetables are deactivated and the micro-organisms present killed by heat. The sealed can excludes air from the foodstuff to prevent subsequent deterioration. The lowest necessary heat and the minimum processing time are used in order to prevent the mechanical breakdown of the product and to preserve the flavor as far as is possible. The can is then able to be stored at ambient temperatures for a long period. Freezing vegetables and maintaining their temperature at below −10 °C (14 °F) will prevent their spoilage for a short period, whereas a temperature of −18 °C (0 °F) is required for longer-term storage. The enzyme action will merely be inhibited, and blanching of suitably sized prepared vegetables before freezing mitigates this and prevents off-flavors developing. Not all micro-organisms will be killed at these temperatures and after thawing the vegetables should be used promptly because otherwise, any microbes present may proliferate.
By the middle of 1982, the Soviet Union alone maintained major mycological herbaria across 25 research institutions or museums and 11 universities, academies, and institutes, together preserving more than one million fungal specimens, including over 5,000 type specimens. The transition from morphology-based systematics to phylogenetics in the 1980s and 1990s further changed the role of historical collections, as scientists began extracting DNA from specimens collected more than a century earlier. Historical plant herbaria as well as dedicated mycological collections have also yielded valuable fungal and oomycete records when older specimens were re-examined for disease symptoms that were not the original focus of collection.
In December 2005, Eli Lilly and Company pleaded guilty and paid $36 million in connection with the illegal promotion of Raloxifene (Evista), a medication typically used to prevent and treat osteoporosis in postmenopausal women. Sales representatives were trained to promote Evista for breast cancer and cardiovascular disease, to prompt or bait questions from doctors, and to send them unsolicited letters promoting Evista for unapproved use. The company also distributed a videotape in which a sales representative declared that "Evista truly is the best drug for the prevention of all these diseases." Some sales representatives had also been instructed to conceal the disclosure page which stated that the effectiveness of the drug in reducing breast cancer risks had not yet been established.
Sources: en.wikipedia.org
Cephalopods are widely regarded as the most intelligent of the invertebrates and have well-developed senses and large brains (larger than those of gastropods). The nervous system of cephalopods is the most complex of the invertebrates and their brain-to-body-mass ratio falls between that of endothermic and ectothermic vertebrates. Captive cephalopods have been known to climb out of their aquaria, maneuver a distance of the lab floor, enter another aquarium to feed on captive crabs, and return to their own aquarium. The brain is protected in a cartilaginous cranium. The giant nerve fibers of the cephalopod mantle have been widely used for many years as experimental material in neurophysiology; their large diameter (due to lack of myelination) makes them relatively easy to study compared with other animals. Many cephalopods are social creatures; when isolated from their own kind, some species have been observed shoaling with fish. Some cephalopods are able to fly through the air for distances of up to 50 metres (160 ft). While cephalopods are not particularly aerodynamic, they achieve these impressive ranges by jet-propulsion; water continues to be expelled from the funnel while the organism is in the air. The animals spread their fins and tentacles to form wings and actively control lift force with body posture. One species, Todarodes pacificus, has been observed spreading tentacles in a flat fan shape with a mucus film between the individual tentacles, while another, Sepioteuthis sepioidea, has been observed putting the tentacles in a circular arrangement.
Benzoylfentanyl, also known as phenylfentanyl, is an opioid analgesic that is an analog of fentanyl and has been sold as a designer drug. In the United States, benzoylfentanyl was first identified in Drug Enforcement Administration drug seizures in 2018.
==== Renaissance and Reformation (c. 1400–1550) ==== Johannes Gutenberg's moveable‐type printing press (c. 1450s) ushered in the information age and rise of newspapers. Conquest of Constantinople by the Ottoman Empire (1453) marked the fall of the Byzantine Empire. Christopher Columbus's first voyage to the Americas (1492) initiated sustained contact between Europe and the New World. Amerigo Vespucci's Mundus Novus letter (1503), the first explicit articulation in print of the hypothesis that the lands discovered by European navigators to the west were not the edges of Asia but rather an entirely different continent, is published. Niccolò Machiavelli's The Prince (c. 1513), a foundational work of modern political philosophy. Martin Luther's posting of the 95 Theses (1517) ignited the Reformation. The broader Age of Discovery saw unprecedented maritime exploration and early colonial empires. Nicolaus Copernicus's De revolutionibus orbium coelestium (1543) proposes that the Earth revolves around the Sun. Council of Trent (1545) begins the Catholic Counter-Reformation. Rise of Mercantilism as the prevailing economic theory.
The Brazilian Communist Party (Portuguese: Partido Comunista Brasileiro, PCB), originally the Communist Party of Brazil (Portuguese: Partido Comunista do Brasil), is a Marxist-Leninist party in Brazil, founded on 25 March 1922. Arguably the oldest active political party in Brazil, it played an important role in the country's 20th-century history despite the relatively small number of members. During the First Brazilian Republic era, the party opposed the ruling political order. Although the PCB was founded after the end of the tenentism movement, its most prominent leader, Luís Carlos Prestes, had previously led the Coluna Prestes (a rebel army which marched throughout the country) and later joined the party, becoming one of its leading figures. The PCB supported the Revolution of 1930 before later becoming an opponent of the Vargas government. The party was outlawed during the Estado Novo (1937–1945), briefly returned to legality after the dictatorship's fall, and was banned again in 1947, remaining underground for most of the following four decades. In the 1960s, the Sino-Soviet split led to a factional dispute that resulted in the formation of the PCdoB (Communist Party of Brazil) of Maoist orientation. Despite the split, both communist parties were united in opposition to the Brazilian military government that ruled from 1964 to 1985.
Most commercial 99Mo/99mTc generators use column chromatography, in which 99Mo in the form of water-soluble molybdate, MoO42− is adsorbed onto acid alumina (Al2O3). When the 99Mo decays, it forms pertechnetate TcO4−, which, because of its single charge, is less tightly bound to the alumina. Pulling normal saline solution through the column of immobilized 99MoO42− elutes the soluble 99mTcO4−, resulting in a saline solution containing the 99mTc as the dissolved sodium salt of the pertechnetate. One technetium-99m generator, holding only a few micrograms of 99Mo, can potentially diagnose 10,000 patients because it will be producing 99mTc strongly for over a week.
Sources: en.wikipedia.org
Novo Nordisk has also developed a genetically engineered insulin independently using a yeast process. According to a survey that the International Diabetes Federation conducted in 2002 on the access to and availability of insulin in its member countries, approximately 70% of the insulin that is currently sold in the world is recombinant, biosynthetic 'human' insulin. A majority of insulin used clinically today is produced this way, although clinical experience has provided conflicting evidence on whether these insulins are any less likely to produce an allergic reaction. Adverse reactions have been reported; these include loss of warning signs that patients may slip into a coma through hypoglycemia, convulsions, memory lapse and loss of concentration. However, the International Diabetes Federation's position statement from 2005 is very clear in stating that "there is NO overwhelming evidence to prefer one species of insulin over another" and "[modern, highly purified] animal insulins remain a perfectly acceptable alternative." Since January 2006, all insulins distributed in the US and some other countries are synthetic "human" insulins or their analogues. A special FDA importation process is required to obtain bovine or porcine derived insulin for use in the US, although there may be some remaining stocks of porcine insulin made by Lilly in 2005 or earlier, and porcine lente insulin is also sold and marketed under the brand name Vetsulin(SM) in the US for veterinary usage in the treatment of companion animals with diabetes.
Interpreting pet food labels – Pet food labeling according to AAFCO regulations National Research Council (U.S.). Subcommittee on Dog Nutrition (1974). Nutrient requirements of dogs. National Academy of Sciences. ISBN 978-0-309-02315-3.
=== Individual and community well-being === The distinction between individual and community well-being is central to understanding how societies flourish at different levels and for evaluating trade-offs in policy decisions. Individual well-being concerns the quality of life of a particular person and is the main focus of disciplines such as psychology and some schools of philosophy. Community well-being applies the concept of well-being to a group of people. It encompasses a broad range of economic, social, environmental, and cultural aspects that influence how the community functions and thrives while ensuring that the community's needs are fulfilled. One view sees community well-being as the sum of the degrees of the well-being of each individual, while others emphasize that the relation between the two is more complex. Individual and community well-being often support each other. For instance, high individual well-being can lead a person to contribute more to their community, and a well-functioning community can make its members happy. However, there can also be tensions, like when changes necessary for community well-being conflict with the individual well-being of certain members. Closely related to community well-being are categories defined for specific demographic groups. For instance, child well-being is about the quality of life of children, including factors such as health, education, material security, and social development in a loving and nurturing environment. Other examples include women's, elderly, student, and employee well-being.
The heart has four valves, which separate its chambers. One valve lies between each atrium and ventricle, and one valve rests at the exit of each ventricle. The valves between the atria and ventricles are called the atrioventricular valves. Between the right atrium and the right ventricle is the tricuspid valve. The tricuspid valve has three cusps, which connect to chordae tendinae and three papillary muscles named the anterior, posterior, and septal muscles, after their relative positions. The mitral valve lies between the left atrium and left ventricle. It is also known as the bicuspid valve due to its having two cusps, an anterior and a posterior cusp. These cusps are also attached via chordae tendinae to two papillary muscles projecting from the ventricular wall. The papillary muscles extend from the walls of the heart to valves by cartilaginous connections called chordae tendinae. These muscles prevent the valves from falling too far back when they close. During the relaxation phase of the cardiac cycle, the papillary muscles are also relaxed and the tension on the chordae tendineae is slight. As the heart chambers contract, so do the papillary muscles. This creates tension on the chordae tendineae, helping to hold the cusps of the atrioventricular valves in place and preventing them from being blown back into the atria. Two additional semilunar valves sit at the exit of each of the ventricles. The pulmonary valve is located at the base of the pulmonary artery. This has three cusps which are not attached to any papillary muscles.
Typically, people have fewer than 36 repeats in the polyQ region, which results in the normal production and cytoplasmic localization of the huntingtin. However, 36 or more repeats result in the production of a mutant huntingtin (mHTT), which causes degeneration of medium spiny neurons. Regions of the brain have differing amounts and reliance on these types of neurons and are affected accordingly. Generally, the number of CAG repeats is related to how much this process is affected, and accounts for about 60% of the variation of the age of the onset of symptoms. The remaining variation is attributed to the environment and other genes that modify the mechanism of HD. About 36 to 39 repeats result in a reduced-penetrance form of the disease, with a much later onset and slower progression of symptoms. In some cases, the onset may be so late that symptoms are never noticed. With very large repeat counts (more than 60), HD onset can occur below the age of 20, known as juvenile HD. Juvenile HD is typically of the Westphal variant that is characterized by slowness of movement, rigidity, and tremors. This accounts for about 7% of HD carriers.
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.
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.