A practical reference on Maleimide chemistry: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2026-05-21. Anything still debated is marked as such rather than presented as settled.
CJC-1295 belongs to a class of synthetic peptides modeled on growth hormone releasing hormone, a forty-four amino acid signal produced by the hypothalamus. The compound is built from the first twenty-nine residues of the natural sequence, with four substitutions introduced at positions 2, 8, 15 and 27. These changes were designed to slow enzymatic breakdown while preserving receptor activation. The result is a peptide that is shorter than native GHRH and considerably more resistant to ordinary clearance pathways in circulation.
Two related forms appear under the CJC-1295 name. The simpler analogue, commonly written as modified GRF(1-29), carries the four substitutions but no additional conjugation. The second form attaches a maleimidopropionic acid linker to a lysine residue, a modification frequently called the drug affinity complex. That linker reacts with the free thiol on serum albumin to form a covalent bond. Because albumin has a long residence time in blood, the conjugated peptide stays in circulation far longer than the unconjugated analogue.
Receptor level activity follows the canonical GHRH pathway. The peptide binds the GHRH receptor, a class B G protein coupled receptor on somatotroph cells of the anterior pituitary. Binding raises intracellular cyclic AMP, which promotes calcium entry and the release of growth hormone into the bloodstream. Because the molecule acts at the same receptor as the endogenous hormone, its effect is superimposed on the natural pulsatile rhythm rather than replacing it. Whether sustained receptor occupation leads to desensitization is not fully settled.
The compound emerged from work at a Canadian biotechnology firm in the early 2000s. Early human studies examined its effect on growth hormone and insulin-like growth factor 1 in healthy volunteers and in people with HIV-associated fat redistribution. Reports described sustained increases in both markers after a single injection. Development did not advance to regulatory approval, and the clinical programme was later discontinued. The molecule is now encountered mainly as a research chemical rather than a marketed medicine.
Two forms circulate in research settings and are frequently confused. One carries the drug affinity complex and is often written as CJC-1295 with DAC; the other lacks that group and is usually called modified GRF(1-29). The two share the same core sequence but differ sharply in how long they persist in blood. Products labelled only as CJC-1295 normally refer to the version carrying the complex. Documentation that omits the distinction leaves the intended molecule ambiguous.
| Property | Value | Notes |
|---|---|---|
| Peptide class | Synthetic GHRH analogue | Built on a 29 residue sequence |
| Primary target | GHRH receptor (GHRHR) | Class B G protein coupled receptor |
| Unconjugated half life | Minutes | Limited by protease degradation |
| Key modification | Four residue substitutions | Positions 2, 8, 15 and 27 |
| Common synonym | Modified GRF(1-29) | Usually denotes the form without DAC |
Both forms act at the pituitary receptor for growth hormone-releasing hormone and increase growth hormone output, which in turn raises insulin-like growth factor 1. A long-acting analog produces sustained rather than pulsatile stimulation, and the physiological consequences of that pattern are not fully settled. Published human data on the extended form remain limited, and much of what circulates in discussion traces to early company reports rather than independent replication. How sustained exposure affects normal feedback remains an open question.
The distinguishing feature of the DAC form is a maleimide-containing group that reacts with the free thiol of cysteine-34 on human serum albumin. This reaction forms a covalent bond without enzymatic assistance, and it takes place after the peptide enters the bloodstream. Because albumin is abundant and long-lived, the attached peptide is carried through circulation far longer than an unmodified fragment would survive. The chemistry is a deliberate pharmacokinetic strategy rather than a change to receptor activity.
Enzymatic protection is a separate mechanism from plasma protein binding. The four substitutions in the backbone reduce recognition by dipeptidyl peptidase IV, which normally cleaves the natural hormone within minutes. Without the reactive group, this resistance still yields only a short window of activity, generally reported in the range of tens of minutes. With it, reported half-lives in early human work extended to several days. The size of that gap is the main practical distinction between the two materials.
Lyophilized material is generally stable for extended periods when held at minus twenty degrees Celsius or below and protected from moisture and light. In solution the peptide is more labile; bond hydrolysis, aggregation and oxidation of susceptible residues all proceed faster at ambient temperature. Repeated freeze and thaw cycles should be avoided because they promote clumping and loss of soluble material. The conjugated variant adds a further consideration, since the maleimide group can hydrolyze in aqueous buffer and lose its ability to react with albumin.
Laboratory handling centers on minimizing exposure to water, heat and oxygen before use. Working solutions are typically prepared in sterile water or a mild buffer, and any residual particulate matter is removed by filtration. When the powder dissolves slowly, a small proportion of acetonitrile or dilute acetic acid is sometimes added as a co-solvent. Containers are kept sealed and desiccated between uses. Records of lot number, reconstitution date and storage conditions support later comparison of results across experiments.
CJC-1295 acts at the growth hormone-releasing hormone receptor, a G-protein-coupled receptor found on somatotroph cells in the anterior pituitary. Binding triggers a rise in cyclic AMP and calcium entry, which promotes release of stored growth hormone. Because the peptide mimics the body's own releasing hormone, it amplifies existing secretory pulses rather than driving continuous output. The size of the response therefore depends partly on the subject's own hormonal rhythm and feedback state.
The attached maleimide group explains the unusual duration of the DAC version. After injection it reacts with the thiol of cysteine-34 on serum albumin, forming a stable covalent bond. The resulting conjugate is too large for rapid kidney filtration and is shielded from many peptidases. Reported half-lives for this form reach several days, whereas the version without the group is cleared in roughly half an hour. That gap is the main pharmacological difference between the two.
Hong Kong has the most skyscrapers of any city in the world. Housing is consistently in high demand, making the city of Hong Kong the most expensive residential property market in the world and one of the most expensive cities in the world. It is also one of the most visited cities in the world. Hong Kong is a highly developed territory and has a Human Development Index (HDI) of 0.955, ranking eighth in the world, and is currently the only place in Asia to be in the top ten. Hong Kong is categorized as an Alpha+ city by the Globalization and World Cities Research Network. The city has the highest life expectancy in the world, and has a public transport usage exceeding 90 percent.
In the 19th century, artificial feeding begin to replace wet nursing, and by 1900, wet nursing no longer existed as an organized profession. Changes to the feeding of infants were both socially and technologically driven. With industrialization, more mothers worked outside the home and could less easily breastfeed their children. Technological changes including the design of artificial feeding methods and the preparation of animal milks and other milk substitutes supported a transition to artificial feeding, but with mixed success. Understanding of both nutrition and sanitation lagged behind the introduction of artificial feeding methods, contributing to extremely high infant mortality rates in the Victorian era.
==== Cylindrical spirals myopathy ==== Cylindrical spirals myopathy is very rare with only 18 individual cases described as of 2013. The majority of cases are sporadic, and has been observed in only 3 families. It is characterized by the presence of cylindrical spirals as the main pathological finding in muscle biopsies. Cylindrical spirals are unusual membrane structures that have a spiral pattern. These membrane structures are seen during electron microscopic examination of the affected muscle. These structures merge into or are surrounded by tubular structures that resemble tubular aggregates. Tubular aggregates are abnormal accumulations of membranous tubules and have been observed in a wide variety of muscle diseases and originate from the sarcoplasmic reticulum. Cylindrical spirals were first described in 1979 and were thought to be a non-specific reaction of skeletal muscle secondary to a metabolic disturbance or muscle fibre injury. The molecular basis of cylindrical spiral myopathy is currently unknown, however a genetic mutation affecting the sarcoplasmic reticulum in some patients seems likely, as SERCA1, calsequestrin, and RYR1 have been shown to bind to cylindrical spirals. Cylindrical spirals have also been shown to react with the mitochondrial enzyme succinate dehydrogenase, which suggests that cylindrical spirals originate from mitochondria. Phenotypes are quite variable, and manifestations can include weakness, abnormal gait, myotonia, cramps, and scoliosis.
Erythromycin 12 hydroxylase (EC 1.14.13.154, EryK) is an enzyme with systematic name erythromycin-D,NADPH:oxygen oxidoreductase (12-hydroxylating) . This enzyme catalyses the following chemical reaction
Sources: en.wikipedia.org
For services to British Business in South-East Asia. John Worsley Knagg, Director, British Council English Language Centre, Singapore. Lam Shiu-kum. For services to medicine in Hong Kong. Gerald John Laving. For services to British business interests, and to the community, in Russia. Ranee Lee Pui-Leung, . For public and community service in Hong Kong. Shelly Lau Lee Lai-kuen, . Director of Home Affairs, Hong Kong. Edmund Kwong Ho Leung. For services to engineering in Hong Kong. Jurek Martin, Washington Bureau Chief, Financial Times. Patrick Joseph McGuinness, lately First Secretary, British Embassy, Abu Dhabi. Evelyn Hugh Norie. For services to British business interests in Hong Kong. Alan Richardson, , Director, Accounting Services, Hong Kong. Rolf Schild. For public and industrial services. Michael John Steere. For services to British engineering in Norway. Ian Robert Strachan, , Director of Social Welfare, Hong Kong. Robert Wallace. For services to British commercial interests overseas. Michael David Williams, Rabbi to the Copernic community in Paris. David Wong Shou-yeh, . For services to business and the community, Hong Kong. The Honourable Samuel Wong Ping-wai, . For public services, Hong Kong. William John Woods. For services to community health care in Brazil. Raymond Wu Wai-yung. For services to psychiatric rehabilitation in Hong Kong. Helen Yu Lai Ching-ping, , Director of Education, Hong Kong.
== Pharmaceutical salmon calcitonin formulations == Calcitonin, as salmon calcitonin (sCT), is available in the pharmaceutical market as an injectable preparation for intravenous, intramuscular or subcutaneous application. Noninvasive sCT preparation as a nasal spray is commercially produced and received US FDA approval under the proprietary name Miacalcin® in 1975 for the treatment of postmenopausal osteoporosis. The bioavailability of Miacalcin® nasal spray relative to the injectable form is between 3% and 5%. Currently, a number of sCT oral preparations are under clinical trials and at least one of them has reached Phase III of clinical approval.
From 1799 to 1812, Legendre served as mathematics examiner for graduating artillery students at the École Militaire and from 1799 to 1815 he served as permanent mathematics examiner for the École Polytechnique. In 1824, Legendre's pension from the École Militaire was stopped because he refused to vote for the government candidate at the Institut National. In 1831, he was made an officer of the Légion d'Honneur. Legendre died in Paris on 9 January 1833, after a long and painful illness, and Legendre's widow carefully preserved his belongings to memorialize him. Upon her death in 1856, she was buried next to her husband in the village of Auteuil, where the couple had lived, and left their last country house to the village. Legendre's name is one of the 72 names inscribed on the Eiffel Tower.
== Brand names == Felviten Halpen Hepasulfol - Franco-Indian Pharmaceuticals Heporal Mucinol - Sanofi-Aventis Sialor - Paladin Laboratories; Pharmascience; Solvay; Zuoz Pharma Sonicur - Solvay Sulfarlem - Solvay; Aguettant; Edward Keller; Sanofi-Aventis Sulfarlem S - EG Labo Tiopropen Tiotrifar
== Personal life == Gallrein lives in Shelbyville, Kentucky. He has been married twice. In December 1985, he married Mary E. Stuart. According to court filings, Gallrein filed to divorce his second wife, Heather Gallrein, in 2024 (one month after losing the Kentucky state legislature election). According to court filings, he told her to "get out of his house" and decided to cut her off financially. Gallrein has denied this claim.
Sources: en.wikipedia.org
Generally speaking single-particle measurement instruments desorb particles one at a time using a pulsed laser. The process is called laser desorption/ionization (LDI) and is the primary ionization method used for single-particle measurements. The main advantage of using LDI over thermal desorption, is the ability to analyze both non-refractory and refractory (e.g., mineral dust, soot) components of atmospheric aerosols. Laser vaporization allows precise laser firing when individual particles fly through the vaporization zone, and the systems are thus dubbed single particle mass spectrometers (SPMS). Several versions of SPMS have been reported, including the aerosol time-of-flight mass spectrometer (AToFMS), the laser mass analyzer for particles in the airborne state (LAMPAS), particle analysis by laser mass spectrometer (PALMS), the rapid single-particle mass spectrometer (RSMS), the bioaerosol mass spectrometer (BAMS) b194 Steele et al., 2003), the nanoaerosol mass spectrometer (NAMS), the single-particle laser ablation time-of-flight mass spectrometer (SPLAT), the single-particle aerosol mass spectrometer (SPAMS), and laser ablation aerosol particle time-of-flight mass spectrometer (LAAP-ToF-MS). Among the most commons of these instruments is the aerosol time-of-flight mass spectrometer (AToFMS).
alpha decay – 70 heavy nuclides (the lightest two are cerium-142 and neodymium-143) double beta decay – 55 nuclides beta decay – tantalum-180m electron capture – tellurium-123, tantalum-180m double electron capture isomeric transition – tantalum-180m These include all nuclides of mass 165 and greater. Argon-36 is the lightest known "stable" nuclide which is theoretically unstable. The positivity of energy release in these processes means they are allowed kinematically (they do not violate conservation of energy) and, thus, in principle, can occur. They are not observed due to strong but not absolute suppression, by spin-parity selection rules (for beta decays and isomeric transitions) or by the thickness of the potential barrier (for alpha and cluster decays and spontaneous fission).
Hypotension (low blood pressure) Dysphoria Tachycardia Malaise Psychomotor impairment It is not believed to be addictive but is known to produce mild withdrawal effects (e.g., anorexia) after abrupt discontinuation.
Many North American sports leagues are made up of teams from different countries—three of the four largest professional leagues have teams representing cities on both sides of the U.S.-Canada border. The same is true for soccer leagues. Although foreign clubs can and do participate in leagues based in the United States, no such team is eligible to participate in the U.S. Open Cup, which is only open to teams affiliated with the United States Soccer Federation (U.S. Soccer). Previously, Canadian teams playing in Major League Soccer (MLS) were not eligible to qualify for the CONCACAF Champions League through the MLS regular season or playoffs; their only method of qualification was through the Canadian Championship, the cup competition run by the Canadian Soccer Association. However, starting from the 2023 MLS season, Canadian teams can qualify for the expanded 2024 CONCACAF Champions League through the MLS regular season or playoffs, or through the Leagues Cup, a competition run by MLS and Liga MX. Those teams that do participate in U.S. leagues also participate in various competitions under their local federations to gain entry into the Champions League and the now defunct CONCACAF League.
Sources: en.wikipedia.org
The names are often used interchangeably in casual writing, but they are not strictly identical. Modified GRF(1-29) refers to the unconjugated analogue carrying only the four substitutions. The version sold as CJC-1295 with DAC includes the albumin binding linker and clears much more slowly.
DAC stands for drug affinity complex, a term describing the maleimidopropionic acid linker. This group forms a covalent bond with the cysteine residue on serum albumin after administration. The resulting adduct is what extends the circulating half life from minutes to days.
No. It is entirely synthetic and does not correspond to any known endogenous peptide. The design starts from human growth hormone releasing hormone and introduces deliberate substitutions. Any biological effect comes from mimicking the natural hormone at its receptor.
It is a synthetic peptide analogue of growth hormone-releasing hormone. Four substitutions in its sequence make it more resistant to enzymatic degradation than the natural hormone. In the version carrying a drug affinity complex, the peptide binds albumin and remains in circulation for days.