If you have been reading about LC-MS/MS 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 2026-01-30. Where a claim depends on a specific study, the study is described rather than over-claimed.
Laboratory studies indicate that GW501516 activates PPARδ, a nuclear receptor involved in fatty acid oxidation and energy metabolism. In rodent experiments, treated animals often showed increased endurance and reduced fat mass. These effects were observed under controlled conditions and do not establish safe or effective use in humans. The exact dose-response relationship in humans remains poorly characterized. Species differences in metabolism can affect how results translate across animals and people.
Safety concerns emerged from long-term animal studies. In rodents given the compound for extended periods, researchers found an increased incidence of certain cancers, including liver and bladder tumors. These findings contributed to the discontinuation of clinical development. Whether similar risks apply to short-term or low-level exposure in humans is not established, and controlled human safety data are limited. The relevance of high-dose rodent carcinogenicity findings to human use remains a subject of debate.
Human trials of GW501516 were small and short in duration. They examined lipid levels, glucose handling, and other metabolic markers, but the programs were halted after the animal cancer findings. No approved therapeutic product exists, and published human data are insufficient for establishing long-term safety. Reports of use for athletic performance come mainly from non-clinical settings and cannot be verified through controlled trials. Independent testing of products sold as cardarine has found inconsistent purity and labeling.
Cardarine is a common name for GW501516, a synthetic compound developed in the 1990s through research collaborations involving GlaxoSmithKline. It belongs to a class of molecules known as peroxisome proliferator-activated receptor delta agonists. Early studies explored its effects on lipid metabolism and energy expenditure in animal models. The compound was never approved as a human medicine, and clinical development was discontinued. In the years since, it has appeared in fitness and bodybuilding communities as a performance-enhancing substance. Regulatory agencies classify it as an unapproved drug.
PPARδ is a nuclear receptor that regulates gene expression related to fatty acid oxidation, glucose homeostasis, and mitochondrial function. GW501516 binds to this receptor with high affinity and activates downstream signaling in skeletal muscle and other tissues. Animal studies reported increased endurance and altered fuel preference, but human data remain limited and inconsistent. The precise relationship between receptor activation and observed physiological changes is still an area of active investigation. Researchers have also examined whether the compound affects inflammation or cell proliferation. No approved therapeutic indication exists for cardarine.
In laboratory settings, cardarine is studied as a tool compound for probing PPARδ biology. Published experiments often use cell cultures, rodent models, or isolated tissues. Some investigations focus on metabolic effects, while others assess potential risks such as carcinogenicity observed in long-term animal studies. Because human trials are sparse, most knowledge comes from preclinical work and adverse event reports. Scientific literature frequently notes the gap between animal findings and human outcomes. The compound is not a dietary supplement and is not intended for human consumption.
| Property | Value | Notes |
|---|---|---|
| Primary target | PPARδ (NR1C2) | Nuclear receptor involved in lipid metabolism |
| Preclinical effect | Increased fatty acid oxidation | Observed in rodent studies |
| Key safety signal | Tumors in rodents after long-term exposure | Contributed to halted clinical development |
| Human trial status | No approved product; development stopped | Limited short-term metabolic data |
| Sport regulatory status | Prohibited at all times | WADA hormone and metabolic modulators class |
Activation of PPARδ changes transcription of genes involved in fatty acid transport, mitochondrial function, and skeletal muscle fuel preference. In rodent studies, pharmacological PPARδ activation was associated with increased endurance and altered body composition. These findings generated interest in performance enhancement, but species differences and study designs limit direct extrapolation to humans. Small human trials were conducted in the 2000s and later discontinued. The extent to which cardarine produces similar metabolic or performance effects in people remains an open question.
The compound is typically described as a laboratory compound rather than a therapeutic product. Published reports have explored its role in lipid disorders, insulin sensitivity, and exercise metabolism, yet no major drug regulator has approved it for medical use. Commercial samples sold under the cardarine name may vary in purity and identity. Analytical confirmation is therefore necessary when the material is discussed in scientific or regulatory contexts. Its classification as a prohibited substance in sport further shapes how it is studied and reported.
Cardarine has no approved therapeutic indication and is not marketed as a medicine. The World Anti-Doping Agency lists GW501516 as a prohibited substance at all times, covering both in-competition and out-of-competition periods. National laws vary: some countries treat it as an unapproved drug subject to import controls, while others have specific restrictions on sale for human consumption. It is often sold as a research chemical, a label that does not imply safety or legality. Enforcement actions have targeted online vendors and shipments.
Anti-doping laboratories identify GW501516 and related metabolites using liquid chromatography coupled with tandem mass spectrometry. Urine is the most common matrix, though blood and dried blood spots may also be analyzed. The method targets the parent compound and phase I and phase II metabolites, which extend the detection window. Because the substance is prohibited at all times, athletes can be tested outside competition. Detection limits and windows depend on the assay, sample type, and individual metabolism.
Cardarine is frequently described as a fat-burning or endurance-enhancing supplement, but these claims exceed the available evidence. The compound is not a hormone, steroid, or selective androgen receptor modulator. Research articles discuss it as a tool compound for studying PPARδ biology, while anti-doping literature focuses on its abuse and detection. Quality of unapproved products is uncertain, and independent analyses have found impurities or incorrect labeling. Open questions include whether human cancer risk resembles that seen in rodents and how often non-athletes use the substance.
In 1966 membership was open to any person of Ukrainian descent 16-65 except those who were pregnant, alcoholics or drug addicts. Had 24,134 members in 1965, 20,000 members in 1995. Headquarters in Scranton, Pennsylvania, where the UFA was founded. National convention held quadrennially. Locals are either called lodges or "local assemblies", Schmidt uses the terms inter-changeably. Later apparently called branches. There was a ritualistic initiation; besides its insurance benefits, it has helped out in natural disaster and war relief; supported the Ivan Franko Scholarship Foundation. Merged with Providence Association of Ukrainian Catholics in America in 2009. Ukrainian National Aid Association - Founded in 1914, more political than the UNA. Headquartered in Pittsburgh. National convention held quadrennially. Locals called lodges, of which there were 170 in 1979. Primarily active in Pennsylvania, Ohio, Illinois, and Canada. 6,928 members in 1965, 8,000 in 1978, 8,710 members in 1995. Merged into the Providence Association of Ukrainian Catholics in America in 2001. Ukrainian National Association
The American Academy of Allergy, Asthma & Immunology (AAAAI); American Board of Allergy & Immunology (ABAI) International Society of Internal Medicine Internal Medicine Society of Australia and New Zealand Archived 2016-08-31 at the Wayback Machine The American Board of Internal Medicine Canadian Society of Internal Medicine The American College of Osteopathic Internists American College of Physicians
Performance of the MasSpec Pen for ovarian cancer diagnosis was further evaluated in a report published in 2019. The authors analyzed 160 human ovarian tissue samples, including 78 normal ovary and 82 serous carcinomas, with the MasSpec Pen and developed classification models to discriminate between the normal and cancer samples. The model was able to distinguish between the normal and cancerous ovarian samples with 98.3%, 100.0%, and 92.3% overall accuracy on a training, validation, and test set of samples. Further, the report evaluated the ability of the MasSpec Pen system to distinguish ovarian cancer from fallopian tube and peritoneum tissue, two of the most common sites for ovarian cancer metastasis. Accuracies of 87.9% and 92.6% were achieved for the discrimination of cancer from fallopian tube and peritoneum tissues, respectively. The MasSpec Pen has also been implemented for the detection of pancreatic cancer during excision procedures. The MasSpec Pen was used on both ex vivo and in vivo tissue samples to discriminate between healthy pancreas and pancreatic tumor tissue. The device was also used to detect cancerous margins near adjacent structures of the pancreas such as the bile duct. The system was used in 18 pancreatic cancer surgeries and the data collected allowed the detection of cancerous tissue with high accuracy.
Sources: en.wikipedia.org
== Metrology == A number of reference materials are available for silver nanoparticles. NIST RM 8017 contains 75 nm silver nanoparticles embedded in a cake of the polymer polyvinylpyrrolidone to stabilize them against oxidation for a long shelf life. They have reference values for mean particle size using dynamic light scattering, ultra-small-angle X-ray scattering, atomic force microscopy, and transmission electron microscopy; and size distribution reference values for the latter two methods. The BAM-N001 certified reference material contains silver nanoparticles with a specified size distribution with a number-weighted median size of 12.6 nm measured by small-angle X-ray scattering and transmission electron microscopy.
It gained momentum when the USSR sent the first human, Yuri Gagarin, into space with the orbital flight of Vostok 1 on April 12, 1961. These were followed by a string of other firsts achieved by the Soviets over the next few years. Gagarin's flight led US president John F. Kennedy to raise the stakes on May 25, 1961, by asking the US Congress to commit to the goal of "landing a man on the Moon and returning him safely to the Earth" before the end of the decade. Both countries began developing super heavy-lift launch vehicles, with the US successfully deploying the Saturn V, which was large enough to send a three-person orbiter and two-person lander to the Moon. Kennedy's Moon landing goal was achieved in July 1969, with the flight of Apollo 11. The USSR continued to pursue crewed lunar programs to launch and land on the Moon before the US with its N1 rocket but did not succeed, and eventually canceled it to concentrate on Salyut, the first space station program, and the first landings on Venus and on Mars. Meanwhile, the US landed five more Apollo crews on the Moon, and continued exploration of other extraterrestrial bodies robotically. A period of détente followed with the April 1972 agreement on a cooperative Apollo–Soyuz Test Project (ASTP), resulting in the July 1975 rendezvous in Earth orbit of a US astronaut crew with a Soviet cosmonaut crew and joint development of an international docking standard APAS-75. Being considered as the final act of the Space Race by many observers, the competition was however only gradually replaced with cooperation.
Plantain plantations are vulnerable to destruction by hurricanes, because Musa spp. do not withstand high winds well. An average plantain provides about 920 kilojoules (220 kilocalories) of food energy and is a good source of potassium and dietary fiber. The sap from the fruit peel, as well as the entire plant, can stain clothing and hands, and can be difficult to remove.
=== Fire-retardant additives === Melamine and its salts are used as fire-retardant additives in paints, plastics, and paper. A melamine fiber, Basofil, has low thermal conductivity, excellent flame resistance and is self-extinguishing; this makes it useful for flame-resistant protective clothing, either alone or as a blend with other fibres.
Sources: en.wikipedia.org
Rodent studies reported increased endurance and fat oxidation after GW501516 exposure. Long-term studies also found higher rates of some tumors, which led to halted development.
Small short-term human trials examined metabolic markers such as lipids and glucose. The trials did not continue after rodent cancer findings, so long-term human safety is unknown.
Controlled human trials have not established a performance benefit. Anecdotal reports exist, but they are not reliable evidence.
Cardarine is a common name for GW501516, a synthetic PPARδ agonist developed for research. It has not been approved as a medication in any country. It is classified as an unapproved drug and a prohibited substance in sport.