This is a working overview of DAC group, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-08-01 and is reviewed periodically as new material appears.
Four amino acid substitutions separate the modified backbone from the parent GRF(1-29) sequence. These changes reduce recognition by dipeptidyl peptidase IV and related proteases, extending the interval before degradation. Development work in this area sought longer-acting GHRH analogs for endocrine investigation. Published descriptions treat the substitution set as a defining property of the core sequence, while the albumin-binding linker is described separately as an optional addition to that same backbone.
CJC-1295 is a synthetic peptide analog of growth hormone-releasing hormone, constructed on the 29-amino-acid fragment designated GRF(1-29). The name began as an internal development code during the 1990s and later spread through research supply catalogs and discussion forums. The molecule does not occur in nature; its sequence is engineered rather than isolated from tissue. Two related compounds are sold under this single label, and they differ by one appended chemical group that strongly influences how long the peptide remains in circulation.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular class | Synthetic peptide | Analog of growth hormone-releasing hormone |
| Chain length | 29 amino acids | Based on the GRF(1-29) fragment |
| Appearance | White to off-white lyophilized powder | Common research supply form |
| Solubility | Soluble in water and aqueous buffers | Powder requires reconstitution before use |
| Typical storage | −20 °C or below | Kept away from light and moisture |
Verification matters because research peptides vary widely in quality. A certificate of analysis is only as reliable as the method behind it, and a single chromatographic trace reveals little about counter-ions, residual solvents, or water content. Independent laboratories commonly pair mass confirmation with chromatographic purity and, where relevant, quantify water along with acetate or trifluoroacetate content. Reported purity figures are not standardized across suppliers, so a stated value such as ninety-eight percent is not directly comparable unless the analytical method, column, and detection wavelength accompany it.
Characterization of this peptide relies on a small set of routine techniques. Reversed-phase high-performance liquid chromatography separates the target from truncated or oxidized by-products and yields a purity estimate when paired with ultraviolet detection near 214 nanometers. Mass spectrometry, either electrospray coupled to liquid chromatography or matrix-assisted laser desorption, confirms that the observed mass matches the value calculated for the expected sequence. Amino acid analysis, and enzymatic digestion followed by fragment mapping, are used when the sequence itself rather than the mass requires verification.
Stability depends heavily on physical state. A lyophilized powder kept dry, desiccated, and shielded from light typically holds its integrity for months to years at minus twenty degrees Celsius, and longer at minus eighty. Once dissolved, the peptide becomes far more vulnerable, since peptide bond hydrolysis, oxidation of susceptible residues, and aggregation all proceed faster in solution. Buffers near neutral pH are generally gentler than strongly acidic or alkaline conditions. Repeated freeze-thaw cycles and exposure to air-liquid interfaces during vigorous mixing cause losses that are easy to overlook.
Two related peptides circulate under the CJC-1295 label, and they differ mainly in how long they persist in circulation. The version carrying a drug affinity complex includes a maleimidopropionic acid linker that forms a covalent bond with serum albumin. The other version, usually written as modified GRF(1-29) or tetrasubstituted GRF(1-29), lacks that linker and is cleared quickly. Mixing the two produces inconsistent readings of published half-life values, because the linker rather than the receptor-facing sequence drives most of the difference.
The core sequence keeps the receptor-binding region of GHRH while replacing four positions that are vulnerable to dipeptidyl peptidase-4 and other proteases. Substitutions at positions 2, 8, 15, and 27 raise metabolic stability relative to the natural hormone. The N-terminal residues remain essential for activity, so changes there generally lower potency. Molecular weight sits near 3368 daltons for the tetrasubstituted analog without the linker, while the albumin-binding form is heavier because of the added maleimide group.
CJC-1295 is a synthetic peptide modeled on growth hormone-releasing hormone, the hypothalamic signal that prompts the pituitary to release growth hormone. Its sequence corresponds to the first twenty-nine residues of human GHRH, with four substitutions that slow enzymatic breakdown. Early descriptions placed the compound in research on growth hormone deficiency and related conditions, and later literature groups it with the long-acting GHRH analogs. The name appears in both laboratory and popular fitness writing, where it sometimes labels chemically different peptides.
CJC-1295 is the name used for a synthetic peptide modeled on growth hormone-releasing hormone, the hypothalamic signal that prompts the pituitary to release growth hormone. The compound was described by a Canadian drug discovery company in the mid-2000s as a long-acting research tool. Two closely related molecules share the name in practice: one carries a drug affinity complex, or DAC, group, and one does not. The distinction matters because the two behave differently in circulation.
The peptide backbone corresponds to GRF(1-29), the first 29 residues of native growth hormone-releasing hormone, which retains most of the receptor-activating activity of the full-length molecule. Four substitutions distinguish the analog from the natural sequence: D-alanine at position 2, glutamine at position 8, alanine at position 15, and leucine at position 27. These changes slow cleavage by dipeptidyl peptidase IV, the enzyme that degrades native hormone in plasma within minutes. The outcome is improved enzymatic stability combined with a still brief residence time when no additional modification is present.
2 AgNO3 → 2 Ag + O2 + 2 NO2 Most metal nitrates thermally decompose to the respective oxides. This may be the case for silver nitrate. Unlike most metal oxides, however, silver oxide readily degrades to the elemental silver.
==== Groundwater ==== In saturated groundwater aquifers, all available pore spaces are filled with water (volumetric water content = porosity). Above a capillary fringe, pore spaces have air in them too. Most soils have a water content less than porosity, which is the definition of unsaturated conditions, and they make up the subject of vadose zone hydrogeology. The capillary fringe of the water table is the dividing line between saturated and unsaturated conditions. Water content in the capillary fringe decreases with increasing distance above the phreatic surface. The flow of water through and unsaturated zone in soils often involves a process of fingering, resulting from Saffman–Taylor instability. This results mostly through drainage processes and produces and unstable interface between saturated and unsaturated regions. One of the main complications which arises in studying the vadose zone, is the fact that the unsaturated hydraulic conductivity is a function of the water content of the material. As a material dries out, the connected wet pathways through the media become smaller, the hydraulic conductivity decreasing with lower water content in a very non-linear fashion. A water retention curve is the relationship between volumetric water content and the water potential of the porous medium. It is characteristic for different types of porous medium. Due to hysteresis, different wetting and drying curves may be distinguished.
== Classification == Gestational diabetes is formally defined as "any degree of glucose intolerance with onset or first recognition during pregnancy". This definition acknowledges the possibility that a woman may have previously undiagnosed diabetes mellitus or may have developed diabetes coincidentally with pregnancy. Whether symptoms subside after pregnancy is also irrelevant to the diagnosis. A woman is diagnosed with gestational diabetes when glucose intolerance continues beyond 24 to 28 weeks of gestation. The White classification, named after Priscilla White, who pioneered research on the effect of diabetes types on perinatal outcome, is widely used to assess maternal and fetal risk. It distinguishes between gestational diabetes (type A) and pregestational diabetes (diabetes that existed before pregnancy). These two groups are further subdivided according to their associated risks and management. The two subtypes of gestational diabetes under this classification system are:
=== Ion exchange === Chelating agents, natural zeolite, activated carbon, ion exchange resins, and liquid organics impregnated with chelating agents are all used to exchange cations or anions with the solution.
Beginning in 1928, Stalin's five-year plans for the national economy of the Soviet Union achieved the rapid industrialisation (coal, iron and steel, electricity and petroleum, among others) and the collectivisation of agriculture. It achieved 23.6% of collectivisation within two years (1930) and 98.0% of collectivisation within thirteen years (1941). As the revolutionary vanguard, the communist party organised Russian society to realise rapid industrialisation programs as defence against Western interference with socialism in Bolshevik Russia. The five-year plans were prepared in the 1920s whilst the Bolshevik government fought the internal Russian Civil War (1917–1922) and repelled the external Allied intervention to the Russian Civil War (1918–1925). Vast industrialisation was initiated mostly based with a focus on heavy industry. The Cultural revolution in the Soviet Union focused on restructuring culture and society.
Sources: en.wikipedia.org
Following months of rumours and investigations, on 13 August 2013, Reid—along with the Essendon Football Club, senior coach James Hird, senior assistant coach Mark Thompson, and football manager Danny Corcoran—was charged by the AFL with bringing the game into disrepute in relation to the supplements program at the club in 2011 and 2012. The club was given 14 days to consider the charges and face an AFL Commission hearing on 26 August 2013. On 27 August 2013, the AFL Commission handed down its decision to exclude Essendon from the 2013 finals series and fine it $2 million. James Hird was banned for 12 months, Danny Corcoran suspended for six months, and Mark Thompson fined $30,000, but the case against Reid continued after his decision to fight the charges against him. On 18 September 2013, 24 hours before Reid was due back in the Supreme Court, the AFL withdrew all 38 charges against him for his role in the supplements scandal, meaning he was free to resume his work at the Essendon Football Club.
Propofol is highly protein-bound in vivo and is metabolized by conjugation in the liver. The half-life of elimination of propofol has been estimated to be between 2 and 24 hours. However, its duration of clinical effect is much shorter because propofol is rapidly distributed into peripheral tissues. When used for IV sedation, a single dose of propofol typically wears off within minutes. Onset is rapid, in as little as 15–30 seconds. Propofol's versatility allows it to be used for short or prolonged sedation, and general anesthesia; and unlike opioid medications, its use is not associated with nausea. These characteristics of rapid onset and recovery along with its amnestic effects have led to its widespread use for sedation and anesthesia.
=== Microarrays === Hybridization-based microarrays use the 3'CCA conserved sequence in tRNAs to attach a fluorescent probe. 70-80 nucleotide long probes, covering the length of the tRNA, are then used to bind tRNAs. tRNAs with at least 8 base differences are able to be distinguished with microarrays, but tRNAs with smaller differences bind to the same probe.
A data logger (also datalogger or data recorder) is an electronic device that records data over time or about location either with a built-in instrument or sensor or via external instruments and sensors. Increasingly, but not entirely, they are based on a digital processor (or computer), and called digital data loggers (DDL). They generally are small, battery-powered, portable, and equipped with a microprocessor, internal memory for data storage, and sensors. Some data loggers interface with a personal computer and use software to activate the data logger and view and analyze the collected data, while others have a local interface device (keypad, LCD) and can be used as a stand-alone device. Data loggers vary from general-purpose devices for various measurement applications to very specific devices for measuring in one environment or application type only. While it is common for general-purpose types to be programmable, many remain static machines with only a limited number or no changeable parameters. Electronic data loggers have replaced chart recorders in many applications. One primary benefit of using data loggers is their ability to automatically collect data on a 24-hour basis. Upon activation, data loggers are typically deployed and left unattended to measure and record information for the duration of the monitoring period. This allows for a comprehensive, accurate picture of the environmental conditions being monitored, such as air temperature and relative humidity.
By repeatedly repulsing Mongol raiders in the 13th century, the sultanate saved India from the devastation visited on West and Central Asia, setting the scene for centuries of migration of fleeing soldiers, scholars, mystics, and artisans from those regions into the subcontinent, thereby creating a syncretic Indo-Islamic culture in the north. The sultanate's raiding and weakening of the regional kingdoms of South India paved the way for the indigenous Vijayanagara Empire. Embracing a strong Shaivite tradition and building upon the military technology of the sultanate, the empire came to control a large portion of peninsular India, and influenced South Indian society long after.
Sources: en.wikipedia.org
== Education == Bry received her bachelor's degree in Genetics and Development from Cornell University, then entered the Medical Scientist Training Program at Washington University School of Medicine in St. Louis. She was the first microbiology graduate student of Dr. Jeffrey I. Gordon and used her background in microbiology and microbial genetics to develop novel systems for studying host-microbial cross-talk within the gastrointestinal tract. She was awarded her MD and a PhD in Molecular Microbiology and Pathogenesis in 1998. She subsequently entered the residency program in Clinical Pathology at Brigham and Women's Hospital. While in her second year of the residency program, she was awarded a Howard Hughes Research Fellowship for Physicians to pursue a postdoctoral fellowship in molecular immunology in the laboratory of Dr. Michael B. Brenner at Brigham and Women's Hospital.
=== Other common diseases === EpiVacCorona, a peptide-based vaccine against COVID-19. IC41 is a peptide vaccine candidate against the Hepatitis C virus. It consists of five synthetic peptides along with the synthetic adjuvant called poly-l-arginine. Multimeric-001 is the most efficient peptide vaccine candidate against influenza. It contains B- and T-cell epitopes from Hemagglutinin. Matrix I and nucleoprotein are combined into a single recombinantly-expressed polypeptide. Alzheimer peptide vaccines: CAD106, UB311, Lu, AF20513, ABvac40, ACI-35, AADvac-1.
=== Pharmacokinetics === Citalopram is considered safe and well tolerated in the therapeutic dose range. Distinct from some other agents in its class, it exhibits linear pharmacokinetics and minimal drug interaction potential, making it a better choice for the elderly or comorbid patients.
== Acquisition == In June 2013, Amgen offered to buy the shares of Onyx Pharmaceuticals for US$120 per share, sending the shares up by around 30% after the news was announced. Onyx announced on June 30, 2013, that it had rejected the unsolicited proffer from Amgen and its board of directors had subsequently authorized their financial advisers to contact other potential acquisition suitors. However after a series of efforts to secure a higher per-share price from other potential buyers repeatedly failed to materialize, the board reversed course and agreed to Amgen's original terms; the acquisition was formally announced on August 25, 2013.
Sources: en.wikipedia.org
No. It is a laboratory-synthesized analog built on a fragment of the natural hormone. The natural peptide is shorter-lived and lacks the stabilizing substitutions found in the synthetic version.
DAC stands for drug affinity complex, a chemical group that binds the peptide to serum albumin. The binding slows clearance and lengthens the time the molecule stays in plasma compared with the unmodified analog.
Because two distinct molecules are discussed under one informal label. The albumin-binding version clears over several days, while the form without that group clears within roughly half an hour. Mixing results from both creates inconsistent figures.
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.