Everything below concerns LC-MS/MS. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2026-02-08. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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.
Because cardarine is not an approved medicine, no pharmacopeial monograph defines its identity, purity, or storage requirements. Laboratories typically rely on in-house methods and reference standards when testing materials labeled as GW501516. Certificates of analysis may report purity and identity for a specific batch, but their scope varies and they do not guarantee safety or legal status. Independent verification can include high-performance liquid chromatography, mass spectrometry, nuclear magnetic resonance, and elemental analysis. The distinction between research chemical labeling and human use is significant because quality standards and oversight differ.
Cardarine can be detected in biological samples and product materials using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). The method separates compounds by chromatography and identifies them by mass-to-charge transitions, allowing low-level detection in urine or blood. Sample preparation often involves enzymatic hydrolysis, solid-phase extraction, or protein precipitation. Certified reference materials and isotope-labeled internal standards improve quantification. Detection windows depend on metabolism, matrix, and assay sensitivity, so no single universal window applies.
| 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 |
Clinical development stopped after rodent studies showed tumors at multiple sites. Whether those findings predict human cancer risk remains an open question, but they led sponsors to discontinue programs. Human safety data are limited to small, short-term studies that were not designed to assess cancer risk. Reported effects in those studies included changes in blood lipids, but the evidence is insufficient for medical use. Long-term consequences of nonmedical use are not well characterized. Questions about dose, duration, and individual susceptibility remain unresolved.
Cardarine is a common name for GW501516, an investigational compound developed in the 1990s for metabolic conditions. It acts as an agonist at peroxisome proliferator-activated receptor delta, a nuclear receptor involved in lipid and energy metabolism. The compound is frequently mislabeled as a selective androgen receptor modulator, or SARM, but its molecular target is different. GW501516 reached early clinical testing before development was discontinued. It has no approved therapeutic use in any country. The name cardarine is not a formal international nonproprietary name.
Quality assessment for cardarine samples usually combines identity, purity, and impurity testing. Nuclear magnetic resonance spectroscopy and mass spectrometry can confirm molecular structure, while high-performance liquid chromatography estimates purity. Certificates of analysis from testing laboratories may list these results, but they do not establish safety or legality. In the absence of approved manufacturing, products sold online may contain the wrong compound, variable amounts, or unlisted contaminants. Independent verification is therefore central to analytical work and to interpreting any reported biological activity.
Laboratory detection of GW501516 commonly uses liquid chromatography coupled with tandem mass spectrometry. The method can identify the parent compound or its metabolites in urine and blood after sample cleanup. Protein precipitation, solid-phase extraction, or enzymatic hydrolysis may precede analysis, depending on the matrix. Reference standards are required for accurate quantification and confirmation. Because the compound is not approved, testing often occurs in anti-doping, forensic, or research settings rather than routine clinical care. Results are reported with limits of detection and quantification.
Stability of GW501516 depends on form, temperature, light exposure, and moisture. Solid reference material is typically stored frozen or refrigerated in a desiccator and protected from light. Solutions in organic solvents such as dimethyl sulfoxide are often kept frozen in aliquots to reduce freeze-thaw cycling. Aqueous solubility is low, so aqueous stock solutions can be difficult to prepare without cosolvents. Degradation may appear as changes in chromatographic purity or mass spectral signal. Stability studies are needed to establish shelf life for any specific preparation.
A persistent misconception is that cardarine is a fat-burning drug or a safe alternative to anabolic steroids. No approved therapeutic product exists, and human safety data are limited. The tumor findings in rodents remain a central concern in scientific reviews. Products sold online may contain inaccurate labels, impurities, or different compounds entirely, which complicates any assessment of effects. Independent testing of such products has reported frequent mislabeling. For these reasons, discussions in the literature emphasize risks and unknowns rather than benefits.
Cardarine is not approved for human therapeutic use in any major jurisdiction. It appears on the World Anti-Doping Agency Prohibited List as a PPARδ agonist within the hormone and metabolic modulators category. Sports organizations test for it because it has been detected in athlete samples and seized products. Regulatory actions against marketed research chemical versions have occurred in several countries, though enforcement varies. Availability through unregulated channels complicates oversight.
Analytical laboratories typically identify cardarine and its metabolites using liquid chromatography-tandem mass spectrometry. Urine is a common matrix in anti-doping testing, while blood and tissue may be used in research settings. Detection windows depend on the assay, the sample matrix, and the compound's metabolism. Because cardarine is extensively metabolized, laboratories often target specific metabolites to improve sensitivity and confirmation. Reference standards are required for reliable quantification. Method validation includes checks for selectivity, linearity, and carryover.
=== Bleeding time === Bleeding time was developed as a test of platelet function by Duke in 1910. Duke's test measured the time taken for bleeding to stop from a standardized wound in the ear lobe that was blotted every 30 seconds, considering less than 3 minutes as normal. Bleeding time has low sensitivity and specificity for mild to moderate platelet disorders and is no longer recommended for screening.
== Function == Cholesterol needs to be transferred from the outer mitochondrial membrane to the inner membrane where cytochrome P450scc enzyme (CYP11A1) cleaves the cholesterol side chain, which is the first enzymatic step in all steroid synthesis. The aqueous phase between these two membranes cannot be crossed by the lipophilic cholesterol, unless certain proteins assist in this process. A number of proteins have historically been proposed to facilitate this transfer including: sterol carrier protein 2 (SCP2), steroidogenic activator polypeptide (SAP), peripheral benzodiazepine receptor (PBR or translocator protein, TSPO), and StAR. It is now clear that this process is primarily mediated by the action of StAR. The mechanism by which StAR causes cholesterol movement remains unclear as it appears to act from the outside of the mitochondria and its entry into the mitochondria ends its function. Various hypotheses have been advanced. Some involve StAR transferring cholesterol itself like a shuttle. While StAR may bind cholesterol itself, the exorbitant number of cholesterol molecules that the protein transfers would indicate that it would have to act as a cholesterol channel instead of a shuttle. Another notion is that it causes cholesterol to be kicked out of the outer membrane to the inner (cholesterol desorption). StAR may also promote the formation of contact sites between the outer and inner mitochondrial membranes to allow cholesterol influx.
Radiofrequency ablation of sensory knee nerves, also called genicular neurotomy or genicular RFA, is an outpatient procedure used to reduce pain from knee osteoarthritis. In the procedure for genicular RFA, a guide cannula is first directed under local anesthesia and imaging (ultrasound or fluoroscopy) to each target genicular nerve, then the radiofrequency electrode is passed through the cannula, and the electrode tip is heated to about 80 °C (176 °F) for one minute to cauterize a small segment of the nerve. The heat destroys that segment of the nerve, which is prevented from sending pain signals to the brain. As of 2023, reviews of clinical outcomes indicated that efficacy for reducing knee pain was achieved by ablating three or more branches of the genicular nerve (one of the articular branches of the tibial nerve). Other sources indicate 4–5 genicular nerve targets may be justified for ablation to optimize pain relief, while a 2022 analysis indicated that as many as 10 genicular nerve targets for RFA would produce better long-term relief of knee pain. Knee pain relief of 50% or more following genicular RFA may last from several months to two years, and can be repeated by the same outpatient procedure when pain recurs. Injection of phenol may be used as a neurolytic treatment of sensory knee nerves to relieve chronic pain from knee osteoarthritis.
=== 1968–1989: Growth and challenges === Rapid growth began in 1968 and Marriott made optimistic projections. In October 1968, there were reportedly 38 units open and 65 under construction, and by December, 56 opened with 39 under construction. Marriott projected 700 or more Roy Rogers restaurants in four years. By June 1969, 105 units were open with a new projection of 870 in four years. A February 1970 newspaper article reported that over 160 units were in operation. However, growth halted in 1970, when Marriott suspended Roy Rogers franchising, due to financial losses from closing failing locations. The following year, the Texas–based regional franchise, Ram-Hart Systems, filed for Chapter 11 protection, asking to terminate unprofitable leases, which made the entire chain unprofitable. After franchising resumed, only 172 restaurants were open by September 1972, a quarter of the 700 stores projected four years earlier.
This is a list of investigational autism and pervasive developmental disorder drugs, or drugs that are currently under development for clinical use in the treatment of autistic spectrum disorders (ASDs) and/or other pervasive developmental disorders (PDDs) but are not yet approved. Chemical/generic names are listed first, with developmental code names, synonyms, and brand names in parentheses. This list was last comprehensively updated in October 2024. It is likely to become outdated with time.
Sources: en.wikipedia.org
== Other == Tuned radio frequency receiver, a type of radio Trinidadian Creole, by ISO 639 code TRF1, French howitzer Thea Realm Fighters, unreleased fighting game for the Atari Jaguar Tropical rainforest, a tropical broadleaf forest with very high rainfall
== Background == In the 1922 parliamentary elections the Democratic Party emerged as the largest party but failed to win a majority of seats. Party leader Afonso Costa subsequently chose not to form government. Instead, António Maria da Silva, also of the Democratic Party, became Prime Minister on 6 February, leading a minority government supported by the Reconstitution Party, the Catholic Centre Party, the Regionalist Party and several independents. However, his government failed to serve a full term after being forced to resign following a motion of no confidence in November 1923. Further instability resulted in seven different governments holding office in the subsequent period until the 1925 elections.
==== William Henry Perkin’s mauveine ==== In 1856, 18 year old William Perkin accidentally discovered a dye he called mauve while trying to make quinine from the oxidation of allyl toluene in his home lab for his academic advisor and boss August Wilhelm von Hoffman. Hoffman reportedly referred to aniline, a major step in the synthesis, as his "first love," and was excited to have Perkin working with it. Perkin communicated with the textile industry, including Pullars of Perth, and John Hyde Christie, the chemist and general manager of John Orr Ewing and Co. about how to best market and produce his dye. He started production of aniline purple near London at the end of 1857 and remained the only producer for at least a few months. Perkin began making the intermediates for his dyes in-house, for example, nitro-benzene, expanding the scale of operations. By the summer of 1859, according to a satirical magazine Punch, London had fallen ill with 'the mauve measles'.
Soon after settling into his new home on Riverside Drive, Adorno met with Lazarsfeld in Newark, New Jersey, to discuss the Project's plans for investigating the impact of broadcast music. Although he was expected to embed the Project's research within a wider theoretical context, it soon became apparent that the Project was primarily concerned with data collection to be used by administrators for establishing whether groups of listeners could be targeted by broadcasts specifically aimed at them. Expected to make use of devices with which listeners could press a button to indicate whether they liked or disliked a particular piece of music, Adorno bristled with distaste and astonishment: "I reflected that culture was simply the condition that precluded a mentality that tried to measure it." Thus, Adorno suggested using individual interviews to determine listener reactions and, only three months after meeting Lazarsfeld, completed a 160-page memorandum on the Project's topic, "Music in Radio." Adorno was primarily interested in how musical material was affected by its distribution through the medium of radio and thought it imperative to understand how music was affected by its becoming part of daily life.
=== Implications in cancer development === There is a growing body of evidence supporting the role of GST, particularly GSTP, in cancer development and chemotherapeutic resistance. The link between GSTP and cancer is most obvious in the overexpression of GSTP in many cancers, but it is also supported by the fact that the transformed phenotype of tumor cells is associated with aberrantly regulated kinase signaling pathways and cellular addiction to overexpressed proteins. That most anti-cancer drugs are poor substrates for GSTP indicates that the role of elevated GSTP in many tumor cell lines is not to detoxify the compounds, but must have another purpose; this hypothesis is also given credence by the common finding of GSTP overexpression in tumor cell lines that are not drug resistant.
Sources: en.wikipedia.org
== Pharmacology == Pimecrolimus is an ascomycin macrolactam derivative. It has been shown in vitro that pimecrolimus binds to FKBP1A and also inhibits calcineurin. Thus pimecrolimus inhibits T-cell activation by inhibiting the synthesis and release of cytokines from T-cells. Pimecrolimus also prevents the release of inflammatory cytokines and mediators from mast cells. Pimecrolimus, like tacrolimus, belongs to the ascomycin class of macrolactam immunosuppressives, acting by the inhibition of T-cell activation by the calcineurin pathway and inhibition of the release of numerous inflammatory cytokines, thereby preventing the cascade of immune and inflammatory signals. Pimecrolimus has a similar mode of action to that of tacrolimus but is more selective, with no effect on dendritic (Langerhans) cells. It has lower permeation through the skin than topical steroids or topical tacrolimus although they have not been compared with each other for their permeation ability through mucosa. In addition, in contrast with topical steroids, pimecrolimus does not produce skin atrophy.
=== Carnivores === Male felids are able to urinate backwards by curving the tip of the glans penis backward. In cats, the glans penis is covered with spines. Penile spines also occur on the glans of male and female spotted hyenas. In male dogs the glans penis is smooth and consists of two parts called the bulbus glandis and pars longa glandis. The glans of a fossa's penis extends about halfway down the shaft and is spiny except at the tip. In comparison, the glans of felids is short and spiny, while that of viverrids is smooth and long.
== Treatment == To contain the virus, cats with suspected or diagnosed FPLV should be kept in isolation. It requires immediate, aggressive treatment if the cat is to survive, as it can be fatal in less than 24 hours. Several articles and publications provide guidance for rescuers and veterinarians for optimizing outcomes. Treatment involves:
The α-globin chains are encoded by two closely linked genes HBA1 and HBA2 on chromosome 16; in a person with two copies on each chromosome, a total of four loci encode the α chain. Two alleles are maternal and two alleles are paternal in origin. Alpha-thalassemias result in decreased alpha-globin production, resulting in an excess of β chains in adults and excess γ chains in fetus and newborns.
This process continues until the entire chain is cleaved into acetyl CoA units. The final cycle produces two separate acetyl CoAs, instead of one acyl CoA and one acetyl CoA. For every cycle, the Acyl CoA unit is shortened by two carbon atoms. Concomitantly, one molecule of FADH2, NADH and acetyl CoA are formed.
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.
Anti-doping laboratories typically use LC-MS/MS to detect GW501516 and its metabolites in urine. The method is sensitive and can identify the compound at low concentrations. Detection depends on sample timing, metabolism, and the specific assay.