clinical development comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Last reviewed on 2026-02-14. Where a claim depends on a specific study, the study is described rather than over-claimed.
GW501516 acts as an agonist at the peroxisome proliferator-activated receptor delta, a nuclear receptor that regulates gene expression. Activation shifts transcription toward genes involved in fatty acid uptake, oxidation, and energy expenditure. The compound does not bind the androgen receptor and therefore differs from anabolic steroids and SARMs. In rodent models, this metabolic shift has been linked to increased running endurance and reduced fat accumulation. The exact downstream pathways in humans remain incompletely characterized.
Early clinical research explored GW501516 for lipid disorders, obesity, and diabetes. Some short-term human studies reported changes in HDL cholesterol, LDL cholesterol, and triglycerides. The development program was discontinued after rodent studies showed dose-dependent tumor formation in multiple tissues, including liver, bladder, stomach, and skin. These findings raised concerns about long-term cancer risk in humans. Because human exposure data are limited, the clinical significance of the rodent tumors remains uncertain.
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.
| Property | Value | Notes |
|---|---|---|
| Primary target | PPARδ | Nuclear receptor; not androgen receptor |
| Studied indications | Dyslipidemia; obesity; diabetes | Early clinical research; development discontinued |
| Rodent toxicity | Tumor formation in multiple tissues | Dose-dependent findings in some studies |
| Human approval | None | No approved therapeutic use |
| Typical analytical method | LC-MS/MS | Used for identity and quantification |
=== Quantity === The volume of semen ejaculate varies but is generally about 1 teaspoonful or less. A review of 30 studies concluded that the average was around 3.4 milliliters (mL), with some studies finding amounts as high as 5.0 mL or as low as 2.3 mL. In a study with Swedish and Danish men, a prolonged interval between ejaculations caused an increase in the sperm count in the semen but not an increase in the semen volume.
== Pharmacokinetics == The pharmacokinetics of ethanol are well characterized by the ADME acronym (absorption, distribution, metabolism, excretion). Besides the dose ingested, factors such as the person's total body water, speed of drinking, the drink's nutritional content, and the contents of the stomach all influence the profile of blood alcohol content (BAC) over time. Breath alcohol content (BrAC) and BAC have similar profile shapes, so most forensic pharmacokinetic calculations can be done with either. Relatively few studies directly compare BrAC and BAC within subjects and characterize the difference in pharmacokinetic parameters. Comparing arterial and venous BAC, arterial BAC is higher during the absorption phase and lower in the postabsorptive declining phase.
Unnatural amino acids incorporated into proteins include heavy atom-containing amino acids to facilitate certain x-ray crystallographic studies; amino acids with novel steric/packing and electronic properties; photocrosslinking amino acids which can be used to probe protein-protein interactions in vitro or in vivo; keto, acetylene, azide, and boronate-containing amino acids which can be used to selectively introduce a large number of biophysical probes, tags, and novel chemical functional groups into proteins in vitro or in vivo; redox active amino acids to probe and modulate electron transfer; photocaged and photoisomerizable amino acids to photoregulate biological processes; metal binding amino acids for catalysis and metal ion sensing; amino acids that contain fluorescent or infra-red active side chains to probe protein structure and dynamics; α-hydroxy acids and D-amino acids as probes of backbone conformation and hydrogen bonding interactions; and sulfated amino acids and mimetics of phosphorylated amino acids as probes of post-translational modifications. Availability of the non-standard amino acid requires that the organism either import it from the medium or biosynthesize it. In the first case, the unnatural amino acid is first synthesized chemically in its optically pure L-form. It is then added to the growth medium of the cell. A library of compounds is usually tested for use in incorporation of the new amino acid, but this is not always necessary, for example, various transport systems can handle unnatural amino acids with apolar side-chains.
Sources: en.wikipedia.org
== Availability == Many insulin analogs and GLP-1 agonists for diabetes treatment are available as injector pens. As with insulin vials, some insulin pens are made with higher concentrations including U-200, U-300, and U-500. Different concentration insulin products may not have the same pharmacokinetic properties as other strengths. The higher concentrations are used to lessen the volume of the injection, and allow the same dose of insulin to be injected with less force. In some cases, these medications may be combined into one pen to be administered daily, for example insulin degludec with liraglutide and insulin glargine with lixisenatide. Combination products are available in fixed-dose ratios and are generally dosed by units of insulin, which will administer a proportional amount of the GLP-1 agonist as well. Another class of medication commonly available as an injector pen is monoclonal antibodies. Due to the molecular size of monoclonal antibodies, they must be administered via injection. Examples of monoclonal antibodies available or studied as injector pens include adalimumab, secukinumab, and alirocumab. CGRP antagonists which are monoclonal antibodies, used for the prevention of migraines, are also available as injector pens. Other monoclonal antibodies designed for home use may also be manufactured as injector pens. Some medications are formulated as injector pens to quicken the onset of action of the medication. This includes epinephrine, which when used to treat anaphylaxis must work as soon as possible.
== Personal life == Dustin's son Mason is the former punter for the University of Cincinnati Bearcats in American football. Dustin's son Max is the current punter for the University of Cincinnati Bearcats and formerly played at the University of Arkansas. In Mason's freshman (first) season in 2021, the Bearcats became the first-ever team from a Group of Five conference to reach the College Football Playoff. Mason's sophomore season in 2022, the Bearcats' last before joining the Power Five Big 12 Conference, saw him named the special teams player of the year in the American Athletic Conference.
The Campaign for Safe Cosmetics has also highlighted concerns. Numerous studies have revealed that hydroquinone, if taken orally, can cause exogenous ochronosis, a disfiguring disease in which blue-black pigments are deposited onto the skin; however, skin preparations containing the ingredient are administered topically. The FDA had classified hydroquinone in 1982 as a safe product—generally recognized as safe and effective (GRASE). Additional studies under the National Toxicology Program (NTP) were suggested to determine whether there is a risk to humans from the use of hydroquinone. NTP evaluation showed some evidence of long-term carcinogenic and genotoxic effects. While hydroquinone remains widely prescribed for treatment of hyperpigmentation, questions raised about its safety profile by regulatory agencies in the EU, Japan, and the USA encourage the search for other agents with comparable efficacy. Several such agents are already available or under research, including azelaic acid, kojic acid, retinoids, cysteamine, topical steroids, glycolic acid, and other substances. One of these, 4-butylresorcinol, has been proven to be more effective at treating melanin-related skin disorders by a wide margin, as well as safe enough to be made available over the counter. In the anthraquinone process, substituted hydroquinones, typically anthrahydroquinone, are used to produce hydrogen peroxide, which forms spontaneously on reaction with oxygen. The type of substituted hydroquinone is selected depending on reactivity and recyclability.
== Detection == With continuing experience, particularly on the upper continental slope in the Gulf of Mexico, the successful prediction of the presence of tubeworm communities continues to improve; however, chemosynthetic communities cannot be reliably detected directly using geophysical techniques. Hydrocarbon seeps that allow chemosynthetic communities (Guaymas Basin) to exist do modify the geological characteristics in ways that can be remotely detected, but the time scales of co-occurring active seepage and the presence of living communities is always uncertain. These known sediment modifications include (1) precipitation of authigenic carbonate in the form of micronodules, nodules, or rock masses; (2) formation of gas hydrates; (3) modification of sediment composition through concentration of hard chemosynthetic organism remains (such as shell fragments and layers); (4) formation of interstitial gas bubbles or hydrocarbons; and (5) formation of depressions or pockmarks by gas expulsion. These features give rise to acoustic effects such as wipeout zones (no echoes), hard bottoms (strongly reflective echoes), bright spots (reflection enhanced layers), or reverberant layers (Behrens, 1988; Roberts and Neurauter, 1990). Potential locations for most types of communities can be determined by careful interpretation of these various geophysical modifications, but to date, the process remains imperfect and confirmation of living communities requires direct visual techniques.
Sources: en.wikipedia.org
Paraneoplastic pemphigus (PNP) is an autoimmune disorder stemming from an underlying tumor. It is hypothesized that antigens associated with the tumor trigger an immune response resulting in blistering of the skin and mucous membranes. While patients with malignant and benign tumors are both at risk, malignancy is associated with high mortality rates (near 90%). Current treatment focuses on general wound healing and administering corticosteroids, which has not demonstrated a high success rate. Recent research developments aim to treat the underlying tumor in order to alleviate the symptoms of PNP.
In the expansion years of the 1950s and 1960s, franchisees were signing 20- or 25-year contracts under the older model. The chain expanded into Canada in 1956, opening restaurants in Winnipeg and Montreal. By 1960, A&W had 2,000 restaurants. In November 1956, F. R. "Fran" Loetterle became the president of the chain. In 1963, the chain opened its first store on Okinawa, which at the time was under American control. In the following years, the chain branched into other foreign markets, including Guam (first territory outside of the North American continent to open a restaurant, in 1961), opened by Scotty Moylan, Mexico, the Philippines (some sources say it opened in the 1990s) and Malaysia. The first restaurant in Malaysia (Malaya at the time) was opened on December 24 that year by Al and Geri Lieboff, a couple from Las Vegas, who got the franchising rights for Malaysia and Singapore. Setting up the chain seemed to be complicated, as they were unable to find a proper site, and in the recruitment process, Malayans had no consent to adorning Western "cabaret girl" style clothes. Already at the time of setup, kids were starting to favor chicken, burgers, and hot dogs rather than rice and curry, and within the next five years, would also see a rise in new locations up to 22 within five years. The first restaurant in Europe opened in Mannheim (near Stuttgart), West Germany in 1962.
DMSO is a polar aprotic solvent and is less toxic than other members of this class, such as dimethylformamide, dimethylacetamide, N-methyl-2-pyrrolidone, and hexamethylphosphoramide (HMPA). DMSO is frequently used as a solvent for chemical reactions involving salts, most notably Finkelstein reactions and other nucleophilic substitutions. It is also extensively used as an extractant in biochemistry and cell biology. Because DMSO is only weakly acidic, it tolerates relatively strong bases and as such has been extensively used in the study of carbanions. A set of non-aqueous pKa values (C-H, O-H, S-H and N-H acidities) for thousands of organic compounds have been determined in DMSO solution. Because of its high boiling point, 189 °C (372 °F), DMSO evaporates slowly at normal atmospheric pressure. Samples dissolved in DMSO cannot as easily be recovered compared to other solvents, as it is very difficult to remove all traces of DMSO by conventional rotary evaporation. One technique to fully recover samples is removal of the organic solvent by evaporation followed by addition of water (to dissolve DMSO) and cryodesiccation to remove both DMSO and water. Reactions conducted in DMSO are often diluted with water to precipitate or phase-separate products. The relatively high freezing point of DMSO, 18.5 °C (65.3 °F), means that at, or just below, room temperature it is a solid.
=== A Beautiful Mind === In 1959, the 1994 Nobel Prize winner in Economics, John Nash, was diagnosed with schizophrenia and was initially treated at McLean Hospital. When he relapsed, he was admitted to Trenton Psychiatric Hospital in New Jersey. His associates at Princeton University pleaded with the hospital director to have Nash admitted to the insulin coma unit, recognizing that it was better staffed than other hospital units. He responded to treatment and was subsequently medicated with neuroleptics. Nash's life story was presented in the film A Beautiful Mind, which accurately portrayed the seizures associated with his treatments. In a review of the Nash history, Fink ascribed the success of coma treatments to the 10% of associated seizures, noting that physicians often augmented the comas by convulsions induced by ECT. He envisioned insulin coma treatment as a weak form of convulsive therapy.
=== Contestants === 1st - Jasmin Bell, Pastry Instructor from Seattle, Washington 2nd - Jonathan Elias, Pastry Chef from Troy, Michigan 3rd - Jessica Scott, Executive Pastry Chef from San Diego, California 4th - Ray Vizcaino, Cake Decorator from San Diego, California 5th - Tyler Davis, Pastry Chef from St. Louis, Missouri 6th - Dina Melendez, Pastry Chef from Brooklyn, New York 7th - Cliff Butler, Pastry Chef from Austin, Texas 8th - Andrea Kratville, Home Baker from Sonora, California
Sources: en.wikipedia.org
It targets PPARδ, a nuclear receptor involved in lipid and energy metabolism. It does not act primarily on androgen receptors. This distinction separates it from SARMs.
Rodent studies found dose-dependent tumors in several organs. The sponsor discontinued the program over cancer concerns. Human risk from long-term use remains unknown.
Controlled human endurance trials are lacking. Animal studies show increased exercise capacity under some conditions. Anecdotal reports are not equivalent to clinical evidence.
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.