freeze-thaw raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2026-01-24. Anything still debated is marked as such rather than presented as settled.
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.
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.
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.
| 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 |
Binding to GHRH receptors on pituitary somatotroph cells triggers cyclic AMP signaling and stimulates growth hormone synthesis and release. Because the peptide acts upstream of the pituitary, effects are mediated through endogenous growth hormone rather than direct receptor activation in peripheral tissues. Increases in insulin-like growth factor 1 are generally described as a downstream consequence. Most published human exposure data come from small early-stage studies, and the clinical significance of the pharmacokinetic profile remains incompletely characterized.
CJC-1295 is a synthetic analogue of growth hormone-releasing hormone, built on the 29-amino-acid GHRH(1-29) fragment. Four substitutions distinguish it from the natural sequence: D-alanine at position 2, glutamine at position 8, alanine at position 15, and leucine at position 27. These changes reduce enzymatic cleavage and extend the peptide's persistence in circulation. The compound is discussed in two forms, one carrying a drug affinity complex and one without it.
The drug affinity complex is a maleimidopropionic acid group attached to a lysine side chain. It reacts with the free thiol of cysteine-34 on circulating albumin, forming a covalent bond. This conjugation keeps the peptide in the bloodstream and shields it from rapid renal filtration and proteolysis. Reported circulation half-lives for the albumin-bound form fall in the range of roughly six to nine days in early human studies.
Two principal forms appear in the literature and in research supply. One carries a drug affinity complex, a maleimide-based group that forms a covalent bond with circulating albumin. This linkage slows clearance and produces a long-lasting elevation of peptide levels. The other form lacks that group and is often labeled MOD GRF(1-29). It has a much shorter circulation time. Both variants retain the same core receptor-binding sequence. Reported half-lives differ substantially between the two.
At the pituitary, the peptide binds the growth hormone-releasing hormone receptor on somatotroph cells. Receptor activation raises intracellular cyclic AMP and triggers release of stored growth hormone. Somatostatin and other hypothalamic signals modulate this response. Negative feedback from insulin-like growth factor 1 also influences output. The same regulatory architecture operates with the native hormone. Whether the synthetic analog alters feedback dynamics over repeated exposure remains an open question. Most published receptor work uses cell models rather than intact human systems.
=== Higher yields and faster growth === Because plants are provided with water, nutrients, and light in a controlled environment, hydroponics allows crops to grow faster and potentially yield more within the same or smaller footprint. Some studies show increases of up to 20–30% in crop yield when compared to traditional farming methods.
all persons who were members of the Southern Sudan Legislative Assembly; and all South Sudanese who were members of the National Assembly of Sudan, by virtue of their membership in that Assembly. Members of the Council of Ministers who are not members of the National Legislative Assembly must participate in its deliberations but do not have the right to vote. Persons who wish to become members of the National Legislative Assembly must fulfill the eligibility requirements set down by the Constitution for membership of the National Legislature.
Medical acupuncture attempts to integrate reflexological concepts, the trigger point model, and anatomical insights (such as dermatome distribution) into acupuncture practice, and emphasizes a more formulaic approach to acupuncture point location. Cosmetic acupuncture is the use of acupuncture in an attempt to reduce wrinkles on the face. Bee venom acupuncture is a treatment approach of injecting purified, diluted bee venom into acupoints. Veterinary acupuncture is the use of acupuncture on domesticated animals.
== See also == 11-Hydroxy-Delta-8-THC 11-Hydroxyhexahydrocannabinol 3'-Hydroxy-THC 7-Hydroxycannabidiol 10-Hydroxy-THC 8,11-Dihydroxytetrahydrocannabinol 11-Hydroxycannabinol Cannabis edible Delta-11-Tetrahydrocannabinol
Sources: en.wikipedia.org
The flowers may be arranged along the stem, developing from the base, as a single flower at the tip of the stem, or as a cluster of flowers. They contain both male (androecium) and female (gynoecium) characteristics and are symmetric radially, but sometimes as a mirror image. Most flowers are large and colourful, except for Medeoleae. Both the petals and sepals are usually similar and appear as two concentric groups (whorls) of 'petals', that are often striped or multicoloured, and produce nectar at their bases. The stamens are usually in two groups of three (trimerous) and the pollen has a single groove (monosulcate). The ovary is located above the attachment of the other parts (superior). There are three fused carpels (syncarpus) with one to three chambers (locules), a single style and a three-lobed stigma. The embryo sac is of the Fritillaria type. Usually indeterminate (lacking terminal flower) as a raceme (Lilium); sometimes reduced to a single terminal flower (Tulipa). When pluriflor (multiple blooms), the flowers are arranged in a cluster or rarely are subumbellate (Gagea) or a thyrse (spike). The flowers are hermaphroditic, actinomorphic (radially symmetric) or slightly zygomorphic (bilaterally symmetric), pedicellate (on a short secondary stem), generally large and showy but may be inconspicuous (Medeoleae). The bracts may (bracteate) or may not (ebracteate) be present.
epistasis The collective action of multiple genes interacting during gene expression. A form of gene action, epistasis can be either additive or multiplicative in its effects on specific phenotypic traits.
== ATP analogues == Biochemistry laboratories often use in vitro studies to explore ATP-dependent molecular processes. ATP analogs are also used in X-ray crystallography to determine a protein structure in complex with ATP, often together with other substrates. Enzyme inhibitors of ATP-dependent enzymes such as kinases are needed to examine the binding sites and transition states involved in ATP-dependent reactions. Most useful ATP analogs cannot be hydrolyzed as ATP would be; instead, they trap the enzyme in a structure closely related to the ATP-bound state. Adenosine 5′-(γ-thiotriphosphate) is an extremely common ATP analog in which one of the gamma-phosphate oxygens is replaced by a sulfur atom; this anion is hydrolyzed at a dramatically slower rate than ATP itself and functions as an inhibitor of ATP-dependent processes. In crystallographic studies, hydrolysis transition states are modeled by the bound vanadate ion. Caution is warranted in interpreting the results of experiments using ATP analogs, since some enzymes can hydrolyze them at appreciable rates at high concentration.
=== 2014 === On January 22, 2014, European Southern Observatory became the first scientific organization to deliver Ultra HD footage at regular intervals. On May 6, 2014, France announced DVB-T2 tests in Paris for Ultra HD HEVC broadcast with objectives to replace by 2020 the current DVB-T MPEG4 HD national broadcast. On May 26, 2014, satellite operator Eutelsat announced the launch of Europe's first Ultra HD demo channel in HEVC, broadcasting at 50 fps. The channel is available on the Hot Bird satellites and can be watched by viewers with 4K TVs equipped with DVB-S2 demodulators and HEVC decoders. In June 2014, the FIFA World Cup of that year (held in Brazil) became the first shot entirely in 4K Ultra HD, by Sony. The European Broadcasting Union (EBU) broadcast matches of the FIFA World Cup to audiences in North America, Latin America, Europe and Asia in Ultra HD via SES' NSS-7 and SES-6 satellites. Indian satellite TV provider unveils its plan to launch 4K UHD service early in 2015 and showcased live FIFA World Cup quarter final match in 4K UHD through Sony Entertainment Television Sony SIX. On June 24, 2014, the CEA updated the guidelines for Ultra High-Definition and released guidelines for Connected Ultra High-Definition, adding support for internet video delivered with HEVC. The CEA is developing a UHD logo for voluntary use by companies that make products that meet CEA guidelines. The CEA also clarified that "Ultra High-Definition", "Ultra HD", or "UHD" can be used with other modifiers and gave an example with "Ultra High-Definition TV 4K".
== Awards and recognition == 2004: GlycoFi is awarded Scientific American’s Top 50 Award for the most innovative manufacturing technology. 2006: The readers of Nature Biotechnology select Gerngross amongst the most remarkable and influential biotechnology personalities of the decade. 2007: Gerngross and Glycofi co-founder Charles Hutchinson are named New Hampshire Entrepreneurs of the Year to honor their success with GlycoFi. 2017: Gerngross received the Contrarian Award from Xconomy in 2017.
Sources: en.wikipedia.org
=== Cancer and diabetes === It has been reported that people with LS in Ecuador are resistant to cancer and diabetes and are somewhat protected against aging. This is consistent with findings in mice with a defective growth hormone receptor gene. Among the approximately 100 individuals in this population, there were no reported cases of diabetes and one case of cancer. A 2019 study of individuals with isolated growth hormone deficiency (IGHD type 1B) in Itabaianinha County, Brazil, demonstrated a phenotype consistent with Laron syndrome. Researchers found that these humans had similarly extended healthspan, with resistance to cancer and attenuated effects of aging, but neither patients with LS nor IGHD experienced an increase in their overall lifespan. Recent studies indicate that individuals with Laron syndrome exhibit significantly lower rates of cancer and enhanced metabolic health, likely as a result of reduced insulin-like growth factor 1 (IGF-1) activity, which decreases cell proliferation and activation of cancer-related pathways.
Kuban Cossacks are Cossacks who live in the Kuban region of Russia. Although many Cossack groups came to inhabit the Western North Caucasus, most of the Kuban Cossacks are descendants of the Black Sea Cossack Host (originally the Zaporozhian Cossacks), and the Caucasus Line Cossack Host. During the Russian Civil War, Kuban Cossacks established their own state, the Kuban People's Republic. They attempted to form a federal union with Ukraine People's Republic, but it was defeated by the White Army forces undert Anton Denikin, and eventually Kuban was overcome by the Bolsheviks.
CO2 + OH− ⇌ HCO−3 A reaction similar to this is almost instantaneous with carbonic anhydrase. The structure of the active site in carbonic anhydrases is well known from a number of crystal structures. It consists of a zinc ion coordinated by three imidazole nitrogen atoms from three histidine units. The fourth coordination site is occupied by a water molecule. The coordination sphere of the zinc ion is approximately tetrahedral. The positively-charged zinc ion polarizes the coordinated water molecule, and nucleophilic attack by the negatively-charged hydroxide portion on carbon dioxide proceeds rapidly. The catalytic cycle produces the bicarbonate ion and the hydrogen ion as the equilibrium:
Genome-based peptide fingerprint scanning (GFS) is a system in bioinformatics analysis that attempts to identify the genomic origin (that is, what species they come from) of sample proteins by scanning their peptide-mass fingerprint against the theoretical translation and proteolytic digest of an entire genome. This method is an improvement from previous methods because it compares the peptide fingerprints to an entire genome instead of comparing it to an already annotated genome. This improvement has the potential to improve genome annotation and identify proteins with incorrect or missing annotations.
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.
Chromatography reports how much material elutes as a single peak but does not confirm what that material is. Mass spectrometry supplies the molecular mass, which is characteristic of a given sequence and its modifications. Together the two methods support both a purity figure and an identity claim.