If you have been reading about drug affinity complex 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.
Last reviewed on 2025-11-01. Where a claim depends on a specific study, the study is described rather than over-claimed.
The peptide binds GHRH receptors on somatotroph cells within the anterior pituitary, triggering a signalling cascade that increases growth hormone secretion. Its improved resistance to dipeptidyl peptidase IV degradation distinguishes it from the parent hormone. In the DAC-bearing version, a maleimide group reacts with a cysteine residue on serum albumin, forming a covalent bond that keeps the peptide in circulation far longer. That albumin attachment is the central design feature separating the two research variants.
Pharmacokinetic behaviour differs sharply between the two forms. The DAC-bearing peptide shows an extended circulation time measured in days, whereas the version without the complex is cleared within roughly half an hour. This gap shapes how researchers design dosing schedules in animal models. Whether the prolonged presence of the DAC form produces effects meaningfully different from the short-acting variant remains an open question, since comparative human data are scarce.
CJC-1295 is a synthetic peptide designed to mimic growth hormone-releasing hormone (GHRH), the endogenous signal that prompts the pituitary gland to release growth hormone. The compound is a modified fragment of the natural hormone, spanning the first twenty-nine amino acids of GHRH with several substitutions that slow enzymatic breakdown. Two variants circulate in research settings: one carrying a drug affinity complex (DAC) and one without it. The DAC-free form is frequently labelled Mod GRF(1-29) in catalogs and discussion forums.
CJC-1295 belongs to a family of synthetic peptides modeled on growth hormone-releasing hormone, the hypothalamic signal that prompts the pituitary to release growth hormone. The compound is built from the first twenty-nine amino acids of the natural human sequence, a fragment that retains full receptor binding capacity. Native growth hormone-releasing hormone is degraded quickly in circulation, so the fragment alone has limited practical value. Early work therefore focused on chemical modifications that preserve receptor binding while slowing enzymatic breakdown. The result is a molecule described in the literature as a long-acting analog of the natural hormone.
Two forms circulate under the CJC-1295 name, and they differ by a single appended group. The version without a drug affinity complex carries four substitutions along the peptide chain, including a D-alanine near the amino terminus and replacements at three other positions. These changes block the enzyme dipeptidyl peptidase IV and remove a methionine residue that is prone to oxidation. The modified fragment is frequently labeled MOD GRF 1-29. Naming conventions are inconsistent across informal sources, which is a common source of confusion.
| Property | Value | Notes |
|---|---|---|
| Molecular weight (with DAC) | ~3647 Da | Calculated from the full amino acid sequence |
| Molecular weight (without DAC) | ~3368 Da | Mod GRF(1-29) variant |
| Appearance | White lyophilized powder | Typical form supplied for research |
| Solubility | Soluble in water | Dissolves in aqueous buffers |
| Receptor target | GHRH receptor | Expressed on pituitary somatotroph cells |
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.
Identity and purity are established with reversed phase high performance liquid chromatography coupled to mass spectrometry. The chromatographic step separates the target peptide from truncated sequences and deletion products, while the mass measurement confirms the expected molecular weight to within a fraction of a dalton. Because the two common variants differ by the presence of the linker, mass alone can distinguish them in the unconjugated state. Amino acid analysis and peptide mapping are used when sequence level confirmation is required.
CJC-1295 is a synthetic peptide designed as a long-acting analogue of growth hormone-releasing hormone (GHRH). Its structure derives from the first 29 amino acids of native GHRH, a fragment often called GRF(1-29). Four substitutions were introduced to slow enzymatic breakdown and extend activity relative to the natural sequence. The compound was developed by ConjuChem as part of a broader effort to improve the pharmacokinetic profile of peptide hormones. It is studied in laboratory and clinical research settings rather than appearing as a naturally occurring substance.
Two related forms circulate in technical discussion under the same family name. The original version carries a drug affinity complex (DAC) that binds covalently to serum albumin after administration, and this linkage substantially extends circulation time. A second form, frequently written as modified GRF(1-29) or CJC-1295 without DAC, lacks that linker and clears much faster. The naming is a frequent source of confusion because the shorthand CJC-1295 can refer to either form depending on the source. Reports sometimes fail to specify which variant was studied.
The peptide backbone includes a D-alanine at position two, which resists cleavage by dipeptidyl peptidase IV, and several other substitutions that reduce degradation. Its molecular weight is roughly 3.4 kDa without the linker and about 3.6 kDa with it. The molecule is water soluble and is normally supplied as a lyophilized powder. Precise sequence and mass values depend on which variant is described, so technical documents usually state the exact form being referenced.
CJC-1295 is a synthetic peptide built as a long-acting analogue of growth hormone-releasing hormone. Its backbone matches the first twenty-nine residues of the natural human hormone, with four amino acid substitutions added to slow enzymatic breakdown. A reactive maleimide group, commonly termed the drug affinity complex, allows the peptide to attach to circulating albumin after administration. That albumin attachment keeps the molecule in the bloodstream for an extended period instead of being cleared within minutes.
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.
On 5 March, armed clashes were reported between Taliban forces and Pakistani border guards in parts of Khost, Paktia, Paktika, Kunar, Nangarhar and Kandahar provinces. The clashes were described as sporadic exchanges of fire along sections of the Afghanistan–Pakistan border. In the Spin Boldak district of Kandahar, local sources reported that four Afghan civilians had been killed in strikes by Pakistani forces. Taliban officials have not confirmed the casualties in Spin Boldak district. In Kabul, residents report hearing sounds of scattered gunfire in parts of the city. In Pakistan's Miranshah, two civilians were killed and one was injured when a missile fired from an unidentified direction struck the Governor Cottage in Cantonment area. In Mohmand district, three civilians were injured when a mortar shell fired by Afghan forces landed on a house. Pakistan claimed to have killed 12 TTP insurgents in an operation in Harnai District. The same day, Taliban-led Afghanistan's Ministry of Defense said that over the past 24 hours, 41 Pakistani soldiers had been killed and 53 others had been wounded in the clashes with Taliban forces. The Ministry added that the Taliban forces had destroyed 12 military post and shot down three reconnaissance drones of Pakistan over the past day. The Ministry also said that they have carried out airstrike on a military base in Pakistan province of Balochistan. Pakistani officials stated that they targeted 41 border outpost belonging to Afghan Taliban forces and Pakistani Taliban, resulting in heavy casualties and material losses.
Homo sapiens FGFR1 oncogene partner 2 (FGFR1OP2), transcript variant 1, mRNA (NCBI) Homo sapiens FGFR1 oncogene partner 2 isoform 1 (NCBI) FGFR1OP2 human gene location in the UCSC Genome Browser. FGFR1OP2 human gene details in the UCSC Genome Browser.
== Regulations == In 1961 phenoperidine was added to the 1931 Convention for Limiting the Manufacture and Regulating the Distribution of Narcotic Drugs by the World Health Organization via the Single Convention on Narcotic Drugs. In the US it is classified as a Drug Enforcement Administration (DEA) Schedule I controlled substance opiate with a corresponding code 9641.
Sources: en.wikipedia.org
The introductions of Mia and Chloe helped further exploration of Ari's fictional backstory. It emerges that after their baby son died, Ari's grief caused him to self-destruct and he was later sent to prison for 10 years. Mia then chose to move away with Chloe, who lost the only father figure she had ever known. Ari is surprised when Chloe turns up in the Bay to see him, and he soon learns that Mia lied to Chloe about why he left them, saying that he did not want to be in their lives anymore. Kipa-Williams explained: "Just before her 10th birthday, Ari ended up getting arrested armed robbery and he went to jail. This left Chloe feeling very confused and hurt as to why he never came back home." The actor also said that Ari has mixed emotions about Chloe's arrival, as he knows that Mia will be close behind her and he is unsure about facing his past so soon. Mia turns up at Ari's door just as he is telling Mac about their history. Kipa Williams branded the exes "star-crossed lovers" and said they had a long history together. Ari knows that things were left unresolved between them and Kipa Williams believed that Ari never stopped loving Mia. After he breaks up with Mac, Ari has an awkward meeting with Mia in the gym. Kipa-Williams explained: "Ari doesn't actually tell Mia he's broken up with Mac, so Mia remains guarded and communicates with him like he's still in a relationship." While Kipa-Williams was disappointed about the end of Ari and Mac's relationship, he relished the opportunity to explore his character's background further with Mia and Chloe.
== Pro-Soviet accounts == Soviet historiography on the Cold War era was overwhelmingly dictated by the Soviet state, and blamed the West for the Cold War. In Britain, the historian E. H. Carr wrote a 14-volume history of the Soviet Union, which was focused on the 1920s and published 1950–1978. His friend R. W. Davies said Carr belonged to the anti-Cold War school of history, which regarded the Soviet Union as the major progressive force in the world, the United States as the world's principal obstacle to the advancement of humanity and the Cold War as a case of American aggression against the Soviet Union. Carr criticized those Anglophone historians, who he felt had unfairly judged the Soviet Union by the cultural norms of Britain and the United States.
The consequences of ENSO in terms of the temperature anomalies and precipitation and weather extremes around the world are clearly increasing and associated with climate change. For example, recent scholarship (since about 2019) has found that climate change is increasing the frequency of extreme El Niño events. Previously there was no consensus on whether climate change will have any influence on the strength or duration of El Niño events, as research alternately supported El Niño events becoming stronger and weaker, longer and shorter. While much longer observation of ENSO is needed to robustly detect changes, a large ensemble experiment with multiple climate models shows an increase of approximately 10% in eastern Pacific ENSO amplitude between the 1901–1960 and 1961–2020 periods of greenhouse-gas increase. Compared to centuries-long runs with pre-industrial GHG concentrations, the ensemble of 1961–2020 results shows twice the likelihood of strong eastern Pacific El Niño events and nine times the likelihood of strong central Pacific La Niña events. The IPCC Sixth Assessment Report summarized the state of the art of research in 2021 into the future of ENSO as follows:
The human ADM gene is localized to a single locus on Chromosome 11 with 4 exons and 3 introns. The ADM gene initially codes for a 185-amino acid precursor peptide, that can be differentially excised to form a number of peptides, including an inactive 53-amino acid AM, e PAMP, adrenotensin and ADM95-146. Mature human ADM is activated to form a 52-amino acid, 6-amino acid ring, that shares moderate structural similarity to the calcitonin family of regulatory peptides (calcitonin, CGRP and amylin). Circulating ADM consists of both the amidated active form (15%) and the glycated inactive form (85%). It has a plasma half-life of 22min, a mean clearance rate of 27.4 mL/kg/min, and an apparent volume of distribution of 880 ± 150 mL/kg. Adrenomedullin consists of 52 amino acids, has 1 intramolecular disulfide bond, and shows a slight homology with the calcitonin gene-related peptide (CGRP). The precursor, called preproadrenomedullin, consists of 185 amino acids and can be cleaved by plasma kallikrein at the Lys-Arg and Arg-Arg sites. By RNA-blot analysis, human adrenomedullin mRNA was found to be expressed in all tissues, and most highly expressed in the placenta, fat cells, lung, pancreatic islets, smooth muscle, and skin.
Sources: en.wikipedia.org
Naturally occurring gadolinium (64Gd) is composed of six stable isotopes, 154Gd, 155Gd, 156Gd, 157Gd, 158Gd and 160Gd, and one long-lived radioisotope, 152Gd, with 158Gd being the most abundant (24.84% natural abundance). The predicted double beta decay of 160Gd has not been observed. In all, 32 radioisotopes of gadolinium have been characterized, with the three most stable being alpha emitters: 152Gd (naturally occurring) with a half-life of 1.08×1014 years, 150Gd with a half-life of 1.79×106 years, and 148Gd (theoretically not beta-stable) with a half-life of 86.9 years. All of the remaining radioactive isotopes have half-lives less than a year, the majority of these having half-lives less than two minutes. There are also 16 metastable isomers, with the most stable being 143mGd (t1/2 = 110 seconds), 145mGd (t1/2 = 85 seconds) and 141mGd (t1/2 = 24.5 seconds). The isotopes with atomic masses lower than the most abundant stable isotope, 158Gd, primarily decay by electron capture to isotopes of europium. For higher atomic masses, the primary decay mode is beta decay to isotopes of terbium.
=== Second House passage === The House of Representatives needed to pass the Senate version of the OBBBA for the bill to reach the President's desk. On July 1, 2025, President Trump and Senate majority leader Thune expressed confidence that the bill would pass in the House. House Republican moderates such as David Valadao and Young Kim of California, and Jeff Van Drew of New Jersey, who are against Medicaid cuts, Nick LaLota of New York, who is against SALT changes, and fiscal conservatives such as Chip Roy and Keith Self of Texas, who oppose federal deficit increases, had expressed opposition by June 30 to the bill in its then-current form. The House Rules Committee voted 7–6 on July 1, 2025, to advance the bill to the floor. Fiscal conservative Republicans Chip Roy and Ralph Norman voted against advancing the bill. Usually, the members of the majority party on the Rules Committee always vote to advance the bill to the floor. A procedural vote on July 2, 2025, while negotiations were ongoing off the House floor, was the longest vote in House history. In the early morning of July 3, 2025, the House approved the final procedural rule vote 219–213. The vote, which began on the evening of July 2, was initially opposed by five Republicans: moderate Brian Fitzpatrick of Pennsylvania and fiscal conservatives Victoria Spartz of Indiana, Andrew Clyde of Georgia, Keith Self of Texas, and Thomas Massie of Kentucky. Eight other fiscal conservative Republicans, including Tim Burchett of Tennessee and Chip Roy of Texas, withheld their votes.
Numerous social media users, including Americans, expressed their opposition to US foreign policy by sharing the resurfaced copies of the letter and its contents. The Guardian website removed the letter after displaying it for more than 20 years, and TikTok began issuing takedowns of videos featuring the letter. Reporting in The Washington Post suggested that the virality of the letter had been limited prior to media coverage, having never trended on TikTok. Many of the TikTok videos covering the letter were critical of bin Laden, and media coverage had exaggerated its significance while elevating the virality of the letter. In July 2025, TikTok hired Erica Mindel, a former Israel Defense Forces instructor and contractor for the US State Department's Special Envoy to Monitor and Combat Antisemitism, as its Public Policy Manager of Hate Speech. Starting in 2026, TikTok began cracking down on the accounts of Palestinian activists and journalists, including Bisan Owda, who had reported on the human rights abuses taking place in Gaza. Media outlets such as Al Jazeera verified that TikTok's new algorithm hid content depending on the user's region, with the app hiding Palestinian content from users in the Middle East.
Sources: en.wikipedia.org
The synthetic peptide keeps the receptor-binding region of GHRH but carries substitutions that resist enzymatic cleavage. In the DAC version, an added group also anchors the molecule to albumin, extending its presence in the bloodstream.
The maleimide group forms a covalent link with albumin, an abundant blood protein. This attachment slows clearance, so a single administration persists much longer than the unmodified peptide. The feature is the main reason the two variants are handled differently in study design.
It is not an approved therapeutic product in major regulatory jurisdictions. It appears in research chemical catalogs and scientific literature rather than pharmacy shelves. Clinical development was limited and did not reach approval.
The mass difference from the linker is large enough for routine detection by mass spectrometry. The unconjugated form gives a single sharp signal at its expected weight. Material that has already reacted with albumin shows a much higher mass and a broadened chromatographic peak.