Everything below concerns CJC-1295. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2026-03-24. Numbers and descriptions here follow the published literature rather than marketing material.
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.
The dividing feature between the two forms is a maleimide-based drug affinity complex, abbreviated DAC. In the DAC-bearing version, a linker attaches the peptide to serum albumin after administration, and that association slows removal from plasma. The version lacking DAC appears in catalogs as MOD GRF(1-29) or tetrasubstituted GRF(1-29). Because informal writing treats both as one item, comparisons drawn from such sources routinely blend measurements taken from two molecules with substantially different behavior.
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 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.
| 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 |
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.
Reported half-lives differ widely between the two variants and between species. Values for the albumin-binding form are usually expressed in days, while the unconjugated form is measured in minutes to a few hours. Sampling schedules, assay sensitivity, and route of administration all influence the numbers, which limits direct comparison across studies. Whether sustained receptor occupancy produces different downstream effects from pulsatile stimulation remains an open question in the published work. Claims about relative potency should therefore be read alongside the specific study design that produced them.
Lyophilised powder is the usual supplied form. The material is hygroscopic, so vials are typically equilibrated to room temperature before opening in order to prevent condensation on the contents. Long-term storage is generally described at minus twenty degrees Celsius or colder, protected from light and moisture. Repeated freeze-thaw cycles are avoided because they promote aggregation and loss of soluble material. A reconstituted solution is considerably less stable than the dry powder and is normally kept refrigerated for short periods only.
Identity and purity are assessed mainly by reversed-phase high-performance liquid chromatography combined with mass spectrometry. The chromatographic separation resolves the target peptide from truncation products and from species carrying oxidised residues, while mass measurement confirms the expected molecular mass. Because the two common variants differ by roughly 280 daltons, a mass determination distinguishes them unambiguously. Purity is often quoted as a percentage of total peak area, although that figure depends on the detection wavelength and the integration method applied.
==== Serotonin binding to 5-HT2C ==== Serotonin is an endogenous non-selective agonist for the 5-HT2C receptor with a binding constant of Ki = 16.0 nM. When serotonin binds to the receptors, the most important contacts are in TM helixes 3, 5 and 6 (Figure 3), while the other four TM helixes do not interact directly with the serotonin compound. When binding of serotonin takes place, the protonated primary amine site forms a salt bridge with D134 residue in TM 3, as well as forming a hydrogen bond with residue S138 in TM 3. The aromatic indole ring forms a strong Van der Waals interaction with residues F223 in TM 5 and F328 in TM 6. The ring falls tight into the receptor pocket, stacked between two phenylalanines. Amine of the indole group forms a hydrogen bond with S219 residue in TM 5 and hydroxide substituent of the indole forms hydrogen bonds both with residue S131 in TM 3 and I332 in TM 6. There is also a strong Van der Waals interaction between the indole and I332 in TM 6.
Conversely, if the UK had such a device, the population could be protected. In 1934, along with a movement to establish a scientific committee to examine these new types of weapons, the RAF offered a £1,000 prize to anyone who could demonstrate a working model of a death ray that could kill a sheep at 100 yards; it went unclaimed.
== Honours and awards == Commonwealth Scholar at Trinity College, Cambridge, 1960-1963 Powell Prize for English Verse, Trinity College, 1961 Vidya Jyothi from the President of Sri Lanka, 1992 Honorary DLitt, Sōka University (Japan), 1996 Doctor of Science (honoris causa), University of Ruhuna, Sri Lanka, 2004 Visiting By-Fellowship, visiting scholar, Churchill College, Cambridge, England 2015/16 Ada Derana Sri Lankan of the Year 2017 - Global Scientist Wickramasinghe was appointed Member of the Order of the British Empire (MBE) in the 2022 New Year Honours for services to science, astronomy and astrobiology.
Sources: en.wikipedia.org
Zipline originated from Romotive, a company founded in 2011 by Keller Rinaudo Cliffton that produced an iPhone-controlled robot. Romotive ceased operations in 2014, after which Rinaudo, Ryan Oksenhorn, William Hetzler, and Keenan Wyrobek began developing a fixed-wing drone platform intended for medical delivery. This effort became the basis for Zipline. The company began operations in Rwanda in October 2016 following a government agreement to deliver blood and medical supplies to rural clinics from a centralized distribution center. A second Rwandan center opened in 2018 as the scope of deliveries expanded to include routine vaccines and essential medicines. Zipline launched operations in Ghana on April 24, 2019 under a government contract that provided drone delivery services to public-sector health facilities. The program later expanded to multiple distribution centers serving additional regions. Beginning in 2020, the company participated in regulatory programs, including the FAA type-certification process for delivery drones in the United States. It also deployed temperature-controlled payload systems to support delivery of vaccines requiring cold-chain conditions, including during COVID-19 vaccination campaigns in parts of Africa. From 2022 onward, Zipline initiated operations outside Africa, including a partner-operated distribution center in Japan and limited pilot projects in the United States. It also introduced a new platform aimed at home deliveries in denser urban and suburban environments.
== AZF1 / AZFa == The AZF1 (Azoospermia Factor 1) gene is likely located in the euchromatic part of the long arm in Yq11.23. AZF1 is 792kb long and just distal to the centromere of the Y chromosome. AZF1 genes are involved in spermatogenesis in the testes. Common phenotypic manifestations of deletions in this region are azoospermia and Sertoli cell-only syndrome. Men with a complete deletion in the AZFa region are unable to produce testicular spermatozoa for ICSI. There are several candidate genes in the AZFa region that have been shown to cause infertility in males: Ubiquitin Specific Peptidase 9, Y-Linked (USP9Y), DEAD Box RNA helices, Box3, Y-linked (DBY), Ubiquitously Transcribed Tetratricopeptide Repeat Containing, Y-linked (UTY), and Thymosin Beta 4, Y-Linked (TB4Y).
=== Drawing paste === In the United Kingdom, a medication containing magnesium sulfate, called "drawing paste", is claimed to be useful for small boils or localised infections, and removing splinters. The standard British Pharmacopoeia composition is dried magnesium sulfate 47.76% (by mass), phenol 0.49%, and glycerol to balance.
=== 1984 === January: U.S. President Ronald Reagan outlines foreign policy which reinforces his previous statements. January 1: Brunei gains independence from the UK. February 13: Konstantin Chernenko is named General Secretary of the Soviet Communist Party. May 24: the U.S. Congress ratifies the Boland Amendment banning U.S. aid to the contras. June 1–10: Operation Blue Star begins. July 28: various allies of the Soviet Union boycott the 1984 Summer Olympics (July 28 – August 12) in Los Angeles. August 11: during a microphone sound check for his weekly radio address, President Ronald Reagan jokes about bombing the Soviet Union. "My fellow Americans", Reagan says. "I'm pleased to tell you today that I've signed legislation that will outlaw Russia forever. We begin bombing in five minutes." The quip is not aired but is leaked to the press. The Soviet Union temporarily puts its defense forces on high alert. October 19: Father Jerzy Popiełuszko assassinated. October 31: Indira Gandhi assassinated. December 16: Margaret Thatcher and the UK government, in a plan to open new channels of dialog with Soviet leadership candidates, meet with Mikhail Gorbachev at Chequers.
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.
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.