This is a working overview of Electrospray ionization, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2025-10-09 and is reviewed periodically as new material appears.
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.
The mechanisms attributed to semax are inferred from animal and cell studies rather than traced to one confirmed target. The most frequently cited pathway involves increased expression of brain-derived neurotrophic factor and nerve growth factor in hippocampal and cortical tissue. Some work points to engagement of melanocortin receptors, particularly MC4, which the parent ACTH fragment can activate. Effects on dopaminergic and serotonergic signalling have also been reported. No single account explains all observed results, and the relative weight of each pathway remains unsettled.
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.
| Property | Value | Notes |
|---|---|---|
| Appearance | White to off-white powder | Lyophilized solid from research suppliers |
| Solubility | Freely soluble in water | Also dissolves in aqueous buffers; solutions are used fresh |
| Typical storage temperature | -20 °C for lyophilized powder | Short-term transport at 2-8 °C is common |
| Common analytical method | Reverse-phase HPLC | Paired with mass spectrometry for identity confirmation |
| Common synonyms | ACTH(4-10) analogue; MEHFPGP | N-terminal methionine retained in the chain |
== Career and research == In 1997, Sereti came to the National Institute of Allergy and Infectious Diseases as a clinical associate in the laboratory of immunoregulation. She became a staff clinician in 2003. Sereti was appointed to a clinical tenure-track position in 2009 and received tenure in 2015. She is chief of the HIV pathogenesis section. Sereti researches the pathogenesis of HIV infection emphasizing mechanisms of immune reconstitution inflammatory syndrome in advanced HIV infection and of serious non-AIDS events in treated HIV-infected patients. She also investigates the pathogenesis of idiopathic CD4 lymphocytopenia (ICL) and immune-based therapeutic strategies of HIV infection and ICL.
== External links == NFE2L2+protein,+human at the U.S. National Library of Medicine Medical Subject Headings (MeSH) This article incorporates text from the United States National Library of Medicine, which is in the public domain.
== tRNA-targeting antibiotics == Oxazolidines (e.g. linezolid) prevent the binding of the initiator tRNA at the P-site. Oxazolidines have been demonstrated to pleiotropically affect initiator-tRNA binding, EF-P (elongation factor P)-stimulated synthesis of peptide bonds, and EF-G-mediated translocation of initiator-tRNA into the P-site. Macrolide, lincosamide and streptogramin classes of antibiotics prevent peptide bond formation and/or the translocation of tRNA from the A-site to the P-site on the ribosome that eventually leads to interference with the elongation step and thus the inhibition of protein translation.
Sources: en.wikipedia.org
==== The "ethnic nose" ==== The open rhinoplasty approach affords the plastic surgeon advantages of ease in securing grafts (skin, cartilage, bone) and, most importantly, in securing the nasal cartilage properly, and so better to make the appropriate assessment and remedy. This procedural aspect can be especially difficult in revision surgery, and in rhinoplastic alteration of the thick-skinned "ethnic nose" of the person of color. The study, Ethnic Rhinoplasty: a Universal Preoperative Classification System for the Nasal Tip (2009), reports that a nasal-tip classification system, based upon skin thickness, has been proposed to aid the surgeon in determining if an open rhinoplasty or a closed rhinoplasty can best correct the defect or deformity affecting the patient's nose.
In March 2002, Yorkshire merged with Tricon Global Restaurants to form Yum! Brands. A few weeks later, Malaysian company KUB took over the franchises in Southeast Asia, aiming to restore its prestige in Malaysia alone and increasing its market share. Subsequently, in January 2003, Yum! announced that A&W and Long John Silver's would move their operational base from Lexington to Louisville, as operating the chains from Lexington was considered "impractical and cost-inefficient", preferring to operate all of its chains from Louisville. Under Yum's management, A&W added franchises with a nostalgic look and modern technology. They have a carhop design with drive-thrus, and some have picnic tables. The chain didn't seek to compete against McDonald's, instead preferring to carve up its own niche. 2004 saw the return of the Papa Burger brand at a restaurant in Dayton - the Burger Family brand originally retired in the United States in the 1980s, being replaced by the Deluxe Burgers - and was the only name of the old line that was reinstated, with the other burgers having new names. In September 2001 the Singapore branch was taken over by KUB, who also oversaw the restaurants in Malaysia. At the time of takeover, it had twelve restaurants, but by November 2002, the number had dwindled to eight. Its restaurants had already been downgraded: the Ang Mo Kio restaurant shut down, the Tampines restaurant refused to repair its air conditioning systems, and cable TV was switched off in all outlets. Food sales had decreased by about 5-12%.
Although a majority of Millennials and Generation Z would like to get married one day, two fifths deem marriage to be an outdated institution and an overwhelming majority think it is unnecessary for a fulfilling or happy life. Moreover, they generally prefer an equitable partnership to a traditional patriarchal arrangement. Surveys have also documented a marked decline in the desire for children. Close to a quarter of Millennials and Generation Z say they do not want children. Many of them are seeking to be sterilization procedures (vasectomies for men and tubal ligation for women), an uptick most pronounced in politically conservative states, where abortion, and even contraception and sterilization, could be restricted or banned following the Supreme Court decision Dobbs v. Jackson (2022). Some have chosen to have pets in lieu of children, and they frequently refer to these animals as members of their families or their own children ("fur babies"). Generation Z prefer to prioritize professional life and individual self-discovery, are concerned with financial constraints driven by high inflation and taxes, and dislike the perceived constraints of family life. Those who wish to be parents want to achieve financial security and to be in a serious relationship first.
Age over 50 years Dry, non-productive cough on exertion Progressive exertional dyspnea (shortness of breath with exercise) Dry, inspiratory bilateral basal crackles on auscultation (a crackling or popping sound in the lungs during inhalation). Clubbing of the digits, a disfigurement of the finger tips or toes (see image) Abnormal pulmonary function test results, with evidence of restriction and impaired gas exchange. Some of these features are due to chronic hypoxemia (oxygen deficiency in the blood), and are not specific for IPF, they can occur in other pulmonary disorders. IPF should be considered in all patients with unexplained chronic exertional dyspnea who present with cough, inspiratory bilateral basal crackles, or finger clubbing. Assessment of crackles on lung auscultation is a practical way to improve the earlier diagnosis of IPF. Fine crackles, also known as "velcro" crackles are easily recognized by clinicians and are characteristic of IPF. If bilateral fine crackles are present throughout the inspiratory time and are persisting after several deep breaths, and if remaining present on several occasions several weeks apart in a subject aged ≥60 years, this should raise the suspicion of IPF and lead to consideration of an HRCT scan of the chest which is more sensitive than a chest X-ray. As crackles are not specific for IPF, they must prompt a thorough diagnostic process.
Sources: en.wikipedia.org
The idea is to provoke, surprise and delight the diner." elBulli was only open for about six months of the year, from mid-June to mid-December. Adrià spent the remaining six months of the year perfecting recipes in the workshop "elBulliTaller" in Barcelona. The restaurant closed on 30 July 2011. It reopened as a creativity center to foster innovation like his own and entirely new ideas in 2014. elBulli had 3 Michelin stars and was one of the best restaurants in the world. It received first place in the Restaurant Top 50 in 2002. Then in 2005, it ranked second. It was again awarded the first place in 2006, and retained this title in 2007, 2008 and 2009, making a record 5 times in the top spot. In 2010, after elBulli announced it would close for good the next season, the title was awarded to Noma of Copenhagen, Denmark. Adrià is well known for creating "culinary foam". Adrià explored foams created without the addition of cream or egg white; foams are made of a flavoured liquid and an additive (such as lecithin), then aerated through a variety of methods, including whipping with an immersion blender or extrusion from a siphon bottle equipped with N2O cartridges. Further culinary processes (such as freeze-drying or freezing with liquid nitrogen) may be applied to foams as well. Using a single flavoured liquid allows the flavour of the final product to be less diluted and thus more intense. Adrià is the author of several cookbooks including A Day at El Bulli, El Bulli 2003–2004 and Cocinar en Casa (Cooking at Home).
==== Hormone deficiency ==== Children with primary adrenal failure, also called Addison's disease, may experience hypoglycemia after long periods of fasting. Addison's disease is associated with chronically low levels of the stress hormone cortisol, which leads to decreased glucose production. Hypopituitarism, leading to decreased growth hormone, is another cause of hypoglycemia in children, particularly with long periods of fasting or increased exercise.
The absence of salt in the seasoning is justified by the fact that the salt present in the butter at the time was sufficient. Lancelot de Casteau makes no comment on the vegetable, its origin, its price, or the ease or difficulty of finding it on the market. However, he has been using potatoes since at least December 12, 1557, since the dish "boiled potato" appears in the third course of the banquet that he organized on that date for the Joyous Entry of Prince-Bishop Robert of Berghes. As a court cook, he had to use quality products while keeping a reasonable budget, as he worked on his own funds and was only paid after presenting his statement of fees. The potato was cooked in the Principality of Liege sixty years before being offered "as a rarity at the table of the king" of France Louis XIII, in 1616.
Sources: en.wikipedia.org
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.
A fraction of an intranasal dose is thought to reach the central nervous system, and this route is favoured partly for that reason. The proportion is not well characterized. Direct measurement in humans remains difficult with current methods.
Raised BDNF and NGF expression has been reported across several animal studies, which makes the signal fairly consistent. Whether the same change occurs in humans at usable doses is not established. It is best treated as a working hypothesis rather than a confirmed clinical mechanism.
Suppliers normally quote a percentage of total chromatographic peak area, most often from reversed-phase HPLC. That figure says nothing about what the remaining percentage contains, and it depends on the detection wavelength used. A mass spectrometry result is a separate and stronger check on identity.