A practical reference on IGF-1: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2025-11-26 and is reviewed periodically as new material appears.
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 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.
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 (no linker) | ~3.37 kDa | Calculated from peptide sequence |
| Molecular weight (with linker) | ~3.65 kDa | Includes albumin-binding moiety |
| Appearance | White to off-white powder | Typically lyophilized |
| Solubility | Soluble in water | Also dissolves in aqueous buffers |
| Common synonyms | Modified GRF(1-29), DAC:GRF | Usage varies by source |
Studies in this area generally track growth hormone pulses, insulin-like growth factor 1 concentrations, and occasionally body composition endpoints. Most published human data come from early, small trials, and questions about long-term effects remain open. Whether repeated exposure alters pituitary responsiveness over time is not settled. Analytical work relies on immunoassays for the hormones and on mass spectrometry for the peptide itself, because the two measurements answer different questions.
Binding of the peptide to the growth hormone-releasing hormone receptor on pituitary somatotrophs triggers a G protein coupled cascade that raises cyclic AMP and opens calcium channels. The result is greater secretion of growth hormone into the bloodstream. Because the peptide acts at the same receptor as the natural hypothalamic hormone, its effect is amplified pulse size rather than an entirely separate release pathway. Receptor binding alone does not determine the response, since somatostatin tone and other inputs modulate the final output.
Clearance profiles diverge sharply between the two versions. The albumin-binding molecule stays in plasma for several days, whereas the unmodified analog is largely gone within about half an hour in reported work. Cleavage by dipeptidyl peptidase IV is a major contributor to the short life of the unmodified sequence. These gaps mean the two versions cannot be substituted for each other in study design or in reading results side by side.
Reports on this compound commonly follow serum growth hormone and insulin-like growth factor 1 across defined time windows. Protocols differ in sampling frequency, assay platform, and participant characteristics, which makes direct comparison between publications difficult. Some work focuses on pulsatile release patterns instead of average concentrations. Whether repeated exposure alters endogenous hormone rhythms over long periods remains an open question, and the formal literature is thinner than the volume of informal commentary implies.
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.
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.
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.
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Epithelium lines both the outside (skin) and the inside cavities and lumina of bodies. The outermost layer of human skin is composed of dead stratified squamous, keratinized epithelial cells. Tissues that line the inside of the mouth, the esophagus, the vagina, and part of the rectum are composed of nonkeratinized stratified squamous epithelium. Other surfaces that separate body cavities from the outside environment are lined by simple squamous, columnar, or pseudostratified epithelial cells. Other epithelial cells line the insides of the lungs, the gastrointestinal tract, the reproductive and urinary tracts, and make up the exocrine and endocrine glands. The outer surface of the cornea is covered with fast-growing, easily regenerated epithelial cells. A specialised form of epithelium, endothelium, forms the inner lining of blood vessels and the heart, and is known as vascular endothelium, and lining lymphatic vessels as lymphatic endothelium. Another type, mesothelium, forms the walls of the pericardium, pleurae, and peritoneum. In arthropods, the integument, or external "skin", consists of a single layer of epithelial ectoderm from which arises the cuticle, an outer covering of chitin, the rigidity of which varies as per its chemical composition.
==== APCI MS ==== The source for APCI is similar to ESI except that ions are formed by the interaction of the heated analyte solvent with a corona discharge needle set at a high electrical potential. Primary ions are formed immediately surrounding the needle, and these interact with the solvent to form secondary ions that ultimately ionize the sample. APCI is particularly useful for the analysis of nonpolar lipids such as triacylglycerols, sterols, and fatty acid esters.
Starting from the 1990s, major discoveries of exceptionally preserved fossils in deposits known as conservation Lagerstätten contributed to research on dinosaur soft tissues. Chiefly among these were the rocks that produced the Jehol (Early Cretaceous) and Yanliao (Mid-to-Late Jurassic) biotas of northeastern China, from which hundreds of dinosaur specimens bearing impressions of feather-like structures (both closely related to birds and otherwise, see § Origin of birds) have been described by Xing Xu and colleagues. In living reptiles and mammals, pigment-storing cellular structures known as melanosomes are partially responsible for producing colouration. Both chemical traces of melanin and characteristically shaped melanosomes have been reported from feathers and scales of Jehol and Yanliao dinosaurs, including both theropods and ornithischians. This has enabled multiple full-body reconstructions of dinosaur colouration, such as for Sinosauropteryx and Psittacosaurus by Jakob Vinther and colleagues, and similar techniques have also been extended to dinosaur fossils from other localities. (However, some researchers have also suggested that fossilized melanosomes represent bacterial remains.) Stomach contents in some Jehol and Yanliao dinosaurs closely related to birds have also provided indirect indications of diet and digestive system anatomy (e.g., crops). More concrete evidence of internal anatomy has been reported in Scipionyx from the Pietraroja Plattenkalk of Italy. It preserves portions of the intestines, colon, liver, muscles, and windpipe.
Sources: en.wikipedia.org
Druze tradition honors several "mentors" and "prophets", and Elijah (Khidr) is honored as a prophet. Druze venerate Elijah, and he is considered a central figure in Druzism. And due to his importance in Druzism, the settlement of Druze on Mount Carmel had partly to do with Elijah's story and devotion. There are two large Druze towns on the eastern slopes of Mount Carmel: Daliyat al-Karmel and Isfiya. The Druze regard the Cave of Elijah as holy, and identify Elijah as "El-Khidr", the green prophet who symbolizes water and life, a miracle who cures the sick.
==== "FDA-Approved" vs. "FDA-Accepted in Food Processing" ==== The FDA does not approve applied coatings used in the food processing industry. There is no review process to approve the composition of nonstick coatings; nor does the FDA inspect or test these materials. Through their governing of processes, however, the FDA does have a set of regulations that cover the formulation, manufacturing, and use of nonstick coatings. Hence, materials like Polytetrafluoroethylene (Teflon) are not and cannot be considered as FDA Approved, but rather, they are a "FDA Compliant" or "FDA Acceptable".
=== Layers === Dinosaur eggshells are divided into one, two, or three layers of distinct ultrastructure. The innermost layer, known as the mammillary layer or the cone layer, is only found in theropod eggs (the prismatic and ornithoid basic types). It is composed of cone-shaped structures called mammillae at the base of each shell unit. Mammillae are the first part of the eggshell to form. Each mammilla forms from crystals radiating outward from an organic core until they touch neighboring mammillae and grow upwards into the next layer. In spherulitic eggs, the eggs of non-theropod dinosaurs, the eggshell units grow upward from their organic cores; the base of each eggshell unit is rounded, but is not a true mammilla because it does not have a distinct ultrastructure from the top of the unit. The second layer is alternately called the prismatic layer, the columnar layer, the continuous layer, the crystalline layer, the cryptoprismatic layer, the palisade layer, the spongy layer, or the single layer. In this layer, the shell units can be distinct, partially fused together, or entirely continuous. In some dinosaur eggs, the prismatic layer exhibits squamatic ultrastructure, where the prismatic structure is obscured by a rough texture resembling lizard skin. Though rare in non-avian dinosaurs, some theropod eggs and most bird eggs have a third layer (known as the external layer) made up of vertical calcite crystals.
=== Scalp hair loss === Clascoterone is under development for the treatment of androgen-dependent scalp hair loss. Two phase 3 clinical trials were completed and disclosed in December 2025. The drug significantly improved hair growth in both trials. More specifically, target area hair count (TAHC) had a relative improvement of 5.39-fold (539%) in one study and of 1.68-fold (168%) in the other study, both compared to placebo. In other words, hair growth improved in both the placebo and clascoterone groups, but growth improved by about 1.7- to 5.4-fold more with clascoterone than with placebo. The actual absolute changes in hair counts in the different groups have not yet been released.
21 May The WHO informs about the international 2022 monkeypox outbreak in non-endemic countries – an unprecedented number of cases detected outside of Africa after the first of these cases was detected on 6 May. On 24 May, the WHO states that the outbreak can be contained. The main method used for the early containment is 'ring vaccination' – vaccinating close contacts of positive cases via existing vaccines. 23 May Researchers report that CRISPR-Cas9 gene editing has been used to boost vitamin D in tomatoes. A study shows why decarbonization must be accompanied by strategies to reduce the levels of short-lived climate pollutants with near-term effects for climate goals. 24 May Scientists report the first 3D-printed lab-grown wood. It is unclear if it could ever be used on a commercial scale (e.g. with sufficient production efficiency and quality). A CDC study based on electronic health records shows that "one in five COVID-19 survivors aged 18–64 years and one in four survivors aged ≥65 years experienced at least one incident condition that might be attributable to previous COVID-19" or long COVID. On 18 May, an analysis of private healthcare claims shows that of 78,252 patients diagnosed with 'long COVID', 75.8% had not been hospitalized for COVID-19. 25 May – The world's smallest remote-controlled walking robot, measuring just half a millimetre wide, is demonstrated. Potential applications include the clearing of blocked arteries.
Sources: en.wikipedia.org
Surface plasmons have been used to enhance the surface sensitivity of several spectroscopic measurements including fluorescence, Raman scattering, and second-harmonic generation. In their simplest form, SPR reflectivity measurements can be used to detect molecular adsorption, such as polymers, DNA or proteins, etc. Technically, it is common to measure the angle of minimum reflection (angle of maximum absorption). This angle changes in the order of 0.1° during thin (about nm thickness) film adsorption. (See also the Examples.) In other cases the changes in the absorption wavelength is followed. The mechanism of detection is based on the adsorbing molecules causing changes in the local index of refraction, changing the resonance conditions of the surface plasmon waves. The same principle is exploited in the recently developed competitive platform based on loss-less dielectric multilayers (DBR), supporting surface electromagnetic waves with sharper resonances (Bloch surface waves). If the surface is patterned with different biopolymers, using adequate optics and imaging sensors (i.e. a camera), the technique can be extended to surface plasmon resonance imaging (SPRI). This method provides a high contrast of the images based on the adsorbed amount of molecules, somewhat similar to Brewster angle microscopy (this latter is most commonly used together with a Langmuir–Blodgett trough). For nanoparticles, localized surface plasmon oscillations can give rise to the intense colors of suspensions or sols containing the nanoparticles.
Pyrrole-2-carboxylate monooxygenase (EC 1.14.13.130, pyrrole-2-carboxylate oxygenase) is an enzyme with systematic name pyrrole-2-carboxylate,NADH:oxygen oxidoreductase (5-hydroxylating). This enzyme catalyses the following chemical reaction
During the Manhattan Project, the name Tuballoy was used to refer to natural uranium in the refined condition; this term is still in occasional use. Uranium was also codenamed "X-Metal" during World War II. Similarly, enriched uranium was referred to as Oralloy (Oak Ridge alloy), and depleted uranium was referred to as Depletalloy (depleted alloy).
For years I have been endeavouring to find a credible thesis for the development of Buddhist art, and primarily to trace the ancient route by which the art of imperial Rome, etc..., reached the Far East. What I have seen here goes beyond my wildest dreams. If only I had hands enough to copy it all, [for] here in Kizil are about 300 caves, some of them containing frescoes, all of them very old and fine." The French explorer Paul Pelliot and his photographer Charles Nouette, who were in Kucha from January 1907, visited Kizil soon after the German mission, from September 1, 1907, over a few days, and Charles Nouette took many beautiful and informative photographs. Albert von Le Coq came back to Kizil and surrounding areas in 1913–1914, heading the Fourth German Expedition, removing many paintings, including those Grünwedel had left in place, but generally taking much fewer records than his predecessor.
Sources: en.wikipedia.org
No. It is a synthetic analogue modeled on the first 29 residues of human GHRH. The substitutions and any linker are laboratory modifications rather than features of the endogenous peptide.
Early development used the albumin-binding form, and a shorter variant was later discussed under the same label. Because the two differ in half-life and handling, ambiguity arises whenever a source omits the variant designation.
The compound derives from that fragment but is not identical to it. The parent fragment lacks the stabilizing substitutions, so its degradation rate and duration of action differ noticeably.
Reported values cluster in the range of several days, reflecting slow release from the albumin complex. Estimates differ across species and assay platforms. The figure describes circulation time in study settings rather than a fixed property.