A practical reference on reference standard: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2026-05-16 and is reviewed periodically as new material appears.
SR9009 is a synthetic small molecule studied as a REV-ERB agonist. REV-ERBα and REV-ERBβ are nuclear receptors that help regulate circadian rhythms and metabolic gene expression. The compound was identified in academic screening efforts to find synthetic ligands for these receptors. In cell and animal studies, SR9009 alters transcription of genes involved in lipid and glucose metabolism, and it can shift circadian behavior. It is not an approved therapeutic agent.
Mechanistically, SR9009 binds the ligand-binding domain of REV-ERBα/β and enhances recruitment of corepressor complexes. This represses target genes rather than activating them. Because REV-ERB proteins normally compete with ROR proteins at shared response elements, the net effect depends on tissue and timing. Researchers use SR9009 to probe how nuclear receptor signaling links the clock to metabolism, inflammation, and muscle biology. Findings are largely preclinical, and the precise contribution of each receptor subtype remains under study.
Storage conditions for research-grade SR9009 generally involve a freezer at approximately minus twenty degrees Celsius, sometimes lower for long-term preservation. Containers should remain tightly closed and protected from light. Desiccants may be used to limit moisture uptake. Solutions are often stored in aliquots to avoid repeated warming and cooling. Stability data for the compound under various conditions are limited, so laboratories typically follow supplier recommendations and verify performance through periodic analytical checks rather than assuming indefinite stability.
Identity and purity testing for SR9009 commonly uses liquid chromatography coupled with tandem mass spectrometry. This method separates the compound from matrix components and detects it by mass-to-charge transitions, providing sensitive and specific confirmation. Nuclear magnetic resonance spectroscopy can support structural identification, while high-performance liquid chromatography with ultraviolet detection may estimate purity. Because online products labeled as SR9009 may contain other substances or no active compound at all, independent verification is important in research settings. Certificates of analysis are useful but not a substitute for in-house testing.
Laboratory samples of SR9009 are typically supplied as a white to off-white powder. The compound dissolves readily in organic solvents such as dimethyl sulfoxide and ethanol, while its solubility in water is low. Because of this solubility profile, researchers often prepare concentrated stock solutions in an organic solvent before diluting them into aqueous assay buffers. Light exposure, moisture, and repeated freeze-thaw cycles can degrade many small molecules, so handling procedures usually aim to minimize these factors. Purity is commonly checked before use.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic REV-ERB agonist | Small-molecule ligand; not a hormone or peptide |
| Molecular formula | C20H24ClN3O4S | Reported for the free base |
| CAS Registry Number | 1379686-30-2 | Unique chemical identifier |
| Common synonyms | SR9009; stenabolic | Stenabolic is informal and not an official name |
| Reported targets | REV-ERBα and REV-ERBβ | Nuclear receptors linked to circadian and metabolic regulation |
For long-term storage, SR9009 is typically kept as a solid at low temperature, protected from moisture and light. Desiccated conditions limit hydrolysis, while opaque containers reduce photochemical breakdown. Solutions are less stable than solids and are often stored frozen in aliquots to avoid repeated freeze-thaw cycles. Stability data are not standardized across all suppliers, so users should rely on certificate-of-analysis information when available. Degradation may appear as color change, precipitate, or decreased chromatographic purity.
Laboratory identification of SR9009 typically relies on chromatographic separation coupled to mass spectrometry, often with ultraviolet detection as a secondary check. Nuclear magnetic resonance spectroscopy can confirm molecular structure when a reference standard is available. Because many suppliers sell the compound as a research chemical, independent identity testing is important for experimental reproducibility. A single retention time is not sufficient proof of identity, especially when related compounds may be present. Purity assessments usually report a percentage based on area normalization.
SR9009 is generally described as poorly soluble in water and more soluble in organic solvents such as dimethyl sulfoxide and ethanol. Stock solutions are commonly prepared in an organic solvent before dilution into an aqueous buffer or vehicle. Precipitation can occur if the organic fraction is reduced too quickly or if the final concentration exceeds the compound's solubility limit. Sonication or gentle warming may aid dissolution in some protocols, but excessive heat can promote degradation. Container material and pH can also influence observed solubility.
Regulatory and sporting contexts treat SR9009 as a prohibited substance in many elite competitions. Its presence on banned lists reflects concerns about performance enhancement and unknown long-term safety. Analytical chemists have developed methods to detect the parent compound and its metabolites in urine and blood. Literature discussions distinguish between in vitro potency, animal pharmacology, and anecdotal human reports. The latter are difficult to verify because products sold online may lack purity or contain different compounds.
SR9009 is a synthetic small molecule studied as an agonist of the nuclear receptors REV-ERBα and REV-ERBβ. These receptors help regulate circadian rhythms, lipid metabolism, and inflammatory gene expression. In cell and animal experiments, SR9009 alters transcription of clock-controlled genes and metabolic pathways. The compound is not a hormone and does not resemble classical steroid structures. Its activity depends on binding to the ligand-binding domain of REV-ERB, where it can modify corepressor recruitment.
Physicochemical behavior influences handling. SR9009 is described as a solid with limited aqueous solubility, so organic solvents such as dimethyl sulfoxide or ethanol are common in research stock solutions. Aqueous dilution can produce precipitates if the organic content is too low. Light, heat, and repeated freeze-thaw cycles may affect stability. Storage recommendations usually specify a desiccated freezer environment protected from light, but exact stability data depend on the formulation and matrix.
Detection in biological samples can be complicated by rapid metabolism and low circulating concentrations. Some studies report phase I and phase II metabolites, and analytical methods may need to target those species in addition to the parent compound. Immunoassays are not broadly available, so mass spectrometry remains the main confirmatory approach. For anti-doping testing, laboratories look for SR9009 and its metabolites using validated LC-MS methods. Open questions include how long metabolites remain detectable and how different routes of administration alter detection windows.
In laboratory settings, SR9009 is typically characterized by liquid chromatography–mass spectrometry (LC-MS) or high-performance liquid chromatography with ultraviolet detection (HPLC-UV). These methods can confirm identity and estimate purity, but they require reference standards for accurate quantification. Because SR9009 is not a licensed pharmaceutical, no harmonized pharmacopeial monograph exists. Laboratories often validate in-house methods for matrices such as plasma, urine, or cell culture media. Sample preparation may involve protein precipitation or liquid-liquid extraction before analysis.
The mechanism of action involves binding to REV-ERB receptors and recruiting corepressor complexes, which represses target gene transcription. This contrasts with many nuclear receptor agonists that activate transcription. Downstream effects may include changes in autophagy, mitochondrial biogenesis, and lipid handling, but the precise pathways remain an active area of study. Whether these molecular events translate into meaningful physiological effects in humans is unresolved. Most evidence comes from cultured cells and rodent models rather than human participants.
SR9009 is a synthetic small molecule developed as an agonist of the nuclear receptors REV-ERBα (NR1D1) and REV-ERBβ (NR1D2). These receptors help regulate circadian rhythms and metabolic gene expression. In cell and animal studies, SR9009 alters transcription of genes involved in lipid metabolism, inflammation, and mitochondrial function. It is not an approved medicine, and its pharmacological profile in humans remains largely uncharacterized. The compound is frequently discussed in the context of circadian biology and metabolic research rather than clinical use.
In 1600 BCE, the Edwin Smith Papyrus, an Ancient Egyptian medical text, described the heart and its vessels, as well as the brain and its meninges and cerebrospinal fluid, and the liver, spleen, kidneys, uterus and bladder. It showed the blood vessels diverging from the heart. The Ebers Papyrus (c. 1550 BCE) features a "treatise on the heart", with vessels carrying all the body's fluids to or from every member of the body. The Hellenistic Egyptian city of Alexandria was the stepping-stone for Greek anatomy and physiology. Alexandria not only housed the biggest library for medical records and books of the liberal arts in the world during the time of the Greeks but was also home to many medical practitioners and philosophers. Great patronage of the arts and sciences from the Ptolemaic dynasty of Egypt helped raise Alexandria up, further rivalling other Greek states' cultural and scientific achievements.
Since the introduction of medicines for the management of obesity in the 1930s, many compounds have been tried. Most of them reduce body weight by small amounts, and several of them are no longer marketed for obesity because of their side effects. Out of 25 anti-obesity medications withdrawn from the market between 1964 and 2009, 23 acted by altering the functions of chemical neurotransmitters in the brain. The most common side effects of these drugs that led to withdrawals were mental disturbances, cardiac side effects, and drug abuse or drug dependence. Deaths were reportedly associated with seven products. Six medications for long-term use are: liraglutide, naltrexone/bupropion, orlistat, semaglutide, tirzepatide and phentermine/topiramate. There is no information on how these drugs affect longer-term complications of obesity such as cardiovascular disease or death, although studies on semaglutide have shown cardiovascular benefits. After stopping treatment with GLP-1 agonists such as semaglutide, liraglutide and tirzepatide, people regain on average more than half (50–70%) of the lost weight within 1 year. In 2019 a systematic review compared the effects on weight of various doses of fluoxetine (60 mg/d, 40 mg/d, 20 mg/d, 10 mg/d) in obese adults. When compared to placebo, all dosages of fluoxetine appeared to contribute to weight loss but lead to increased risk of experiencing side effects such as dizziness, drowsiness, fatigue, insomnia and nausea during period of treatment. However, these conclusions were from low certainty evidence.
== Organization == The Brigade's origins trace back to July 1941, when a "Fighter Battalion" (Destruction Battalion) led by I.T Gustev was established in the Mekhovsky District. By July 18th, this unit was reorganized into the Mekhovsky Partisan Detachment under the command of K.F Volkov. Following a winter of skirmishes and internal restructuring, the detachment was expanded to a brigade on May 7th, 1942, into the 2nd Belarusian Partisan Brigade. By January 1943, the brigade had grown to include 9 detachments. These were given honorary names of Soviet military and revolutionary figures, such as Suvorov, Chapayev , and Stalin.
Histology image: 07903loa – Histology Learning System at Boston University - "Eye: fovea, RPE" Histology image: 08103loa – Histology Learning System at Boston University - "Integument: pigmented skin" UMass Amherst Libraries (2016-04-29). 7. Pigment Transfer in Skin Cells. Retrieved 2026-05-20 – via YouTube.
Sources: en.wikipedia.org
African histoplasmosis Alternariosis Antibiotic candidiasis (iatrogenic candidiasis) Black piedra Candidal intertrigo Candidal onychomycosis Candidal paronychia Candidal vulvovaginitis Candidid Chromoblastomycosis (chromomycosis, cladosporiosis, Fonseca's disease, Pedroso's disease, phaeosporotrichosis, verrucous dermatitis) Chronic mucocutaneous candidiasis Coccidioidomycosis (California disease, desert rheumatism, San Joaquin Valley fever, valley fever) Congenital cutaneous candidiasis Cryptococcosis Dermatophytid Diaper candidiasis Disseminated coccidioidomycosis (coccidioidal granuloma) Distal subungual onychomycosis Entomophthoromycosis Erosio interdigitalis blastomycetica Favus Fungal folliculitis (majocchi granuloma) Fusariosis Geotrichosis Granuloma gluteale infantum Histoplasmosis (cave disease, Darling's disease, Ohio Valley disease, reticuloendotheliosis) Hyalohyphomycosis Kerion Lobomycosis (keloidal blastomycosis, lacaziosis, Lobo's disease) Mucormycosis Mycetoma (Madura foot, maduromycosis) North American blastomycosis (blastomycetic dermatitis, blastomycosis, Gilchrist's disease) Onychomycosis (dermatophytic onychomycosis, ringworm of the nail, tinea unguium) Oral candidiasis (thrush) Otomycosis Perianal candidiasis Perlèche (angular cheilitis) Phaeohyphomycosis Piedra (trichosporosis) Pityrosporum folliculitis Primary cutaneous aspergillosis Primary cutaneous coccidioidomycosis Primary cutaneous histoplasmosis Primary pulmonary coccidioidomycosis Primary pulmonary histoplasmosis Progressive disseminated histoplasmosis Proximal subungual onychomycosis Rhinosporidiosis South American blastomycosis (Brazilian blastomycosis, paracoccidioidal granuloma, paracoccidioidomycosis) Sporotrichosis (rose-gardener's disease) Systemic candidiasis Tinea barbae (barber's itch, ringworm of the beard, tinea sycosis) Tinea capitis (herpes tonsurans, ringworm of the hair, ringworm of the scalp, scalp ringworm, tinea tonsurans) Tinea corporis (ringworm, tinea circinata, tinea glabrosa) Tinea corporis gladiatorum Tinea cruris (crotch itch, eczema marginatum, gym itch, jock itch, ringworm of the groin) Tinea faciei Tinea imbricata (tokelau) Tinea incognito Tinea manuum Tinea nigra (superficial phaeohyphomycosis, tinea nigra palmaris et plantaris) Tinea pedis (athlete's foot, ringworm of the foot) Tinea versicolor (dermatomycosis furfuracea, pityriasis versicolor, tinea flava) Trichophyton mentagrophytes VII (TMVII) (an emerging sexually transmitted tinea of the genitals, buttocks, face, trunk, and extremities) White piedra White superficial onychomycosis Zygomycosis (phycomycosis)
According to the Endocrine Society, there is "growing evidence suggesting that obesity is a disorder of the energy homeostasis system, rather than simply arising from the passive accumulation of excess weight" and that "obesity pathogenesis involves two related but distinct processes: (1) sustained positive energy balance (energy [caloric] intake > energy expenditure) and (2) resetting of the body weight "set point" at an increased value." In other words, the fundamental cause of obesity is consuming more calories than are used by the body, and the body adapting to a heavier weight as the standard for the individual.
Prince August Wilhelm married his cousin Princess Alexandra Victoria of Schleswig-Holstein-Sonderburg-Glücksburg on 22 October 1908 at the Berliner Stadtschloss. The couple had planned to take up residence in Schönhausen Palace in Berlin, but changed their mind when his father, Kaiser Wilhelm, decided to leave his son the Villa Liegnitz in the Sanssouci Park. In 1912 their only child, Prince Alexander Ferdinand of Prussia, was born. Their Potsdam residence developed into a meeting place for artists and scholars. In the First World War, August Wilhelm was made district administrator (Landrat) of the district of Ruppin; his office and residence was now Schloss Rheinsberg. His personal adjutant Hans Georg von Mackensen played an important role in his life; the two had been close friends since August Wilhelm's youth. These "pronounced homophilic tendencies" contributed to the failure of his marriage to Princess Alexandra Victoria. The couple did not divorce while August Wilhelm's father, Kaiser Wilhelm II, was Emperor, owing to his opposition to the idea.
Moreover, the nucleus of any atom that has a net nuclear spin and that is bonded to a hydrogen atom could potentially be imaged via heteronuclear magnetization transfer MRI that would image the high-gyromagnetic-ratio hydrogen nucleus instead of the low-gyromagnetic-ratio nucleus that is bonded to the hydrogen atom. In principle, heteronuclear magnetization transfer MRI could be used to detect the presence or absence of specific chemical bonds. Multinuclear imaging is primarily a research technique at present. However, potential applications include functional imaging and imaging of organs poorly seen on 1H MRI (e.g., lungs and bones) or as alternative contrast agents. Inhaled hyperpolarized 3He can be used to image the distribution of air spaces within the lungs. Injectable solutions containing 13C or stabilized bubbles of hyperpolarized 129Xe have been studied as contrast agents for angiography and perfusion imaging. 31P can potentially provide information on bone density and structure, as well as functional imaging of the brain. Multinuclear imaging holds the potential to chart the distribution of lithium in the human brain, this element finding use as an important drug for those with conditions such as bipolar disorder.
=== Education === A system of primary and secondary education existed albeit a racially segregated one with one being for non-African students (though intended to be just for white students) and one for African students. The education system in Rhodesia had issues with getting not just instructors but qualified ones. A sole university existed, the University of Rhodesia which was not racially segregated. It offered 3-year bachelor degrees and Doctor of Medicine degrees which could be completed in 6 years. A library system and a number of museums existed in Rhodesia as well.
Sources: en.wikipedia.org
==== Antibodies ==== Two monoclonal antibodies have been approved to target amyloid beta – donanemab and lecanemab – but as of 2025, their role in treatment is uncertain because of side effects, questions about efficacy, and cost. Lecanemab is approved in the US, including a boxed warning about amyloid-related imaging abnormalities. A 2026 meta-analysis found that anti-amyloid antibodies have no effect in the treatment of Alzheimer's disease. A 2026 Cochrane review found no effect or at best small effect. Anti-amyloid antibodies may cause harmful adverse effects and have been shown to slow disease progression only in individuals with "early and mild AD, and cognitive benefits were often marginal."
user error in performing and interpreting the test, biochemical pregnancy (loss of pregnancy before signs of pregnancy are apparent on ultrasound, likely very soon after implantation), non-pregnant production of the hCG molecule (i.e. secretion due to a tumor or the pituitary gland, some diseases of the liver, cancers, including choriocarcinoma and other germ cell tumors, IgA deficiencies, heterophile antibodies, enterocystoplasties, gestational trophoblastic diseases (GTD), and gestational trophoblastic neoplasms). bacterial contamination and blood in urine Spurious evaporation lines may appear on many home pregnancy tests if read after the suggested 3–5 minute window or reaction time, independent of an actual pregnancy. False positives may also appear on tests used past their expiration date.
Progestogens, also sometimes written progestins, progestagens or gestagens, are a class of natural or synthetic steroid hormones that bind to and activate the progesterone receptors (PR). Progesterone is the major and most important progestogen in the body. The progestogens are named for their function in maintaining pregnancy (i.e., progestational), although they are also present at other phases of the estrous and menstrual cycles. The progestogens are one of three types of sex hormones, the others being estrogens like estradiol and androgens/anabolic steroids like testosterone. In addition, they are one of the five major classes of steroid hormones, the others being the androgens, estrogens, glucocorticoids, and mineralocorticoids, as well as the neurosteroids. All endogenous progestogens are characterized by their basic 21-carbon skeleton, called a pregnane skeleton (C21). In similar manner, the estrogens possess an estrane skeleton (C18), and androgens, an androstane skeleton (C19). The terms progesterone, progestogen, and progestin are mistakenly used interchangeably both in the scientific literature and in clinical settings. Progestins are synthetic progestogens and are used in medicine. Major examples of progestins include the 17α-hydroxyprogesterone derivative medroxyprogesterone acetate and the 19-nortestosterone derivative norethisterone. The progestins are structural analogues of progesterone and have progestogenic activity similarly, but differ from progesterone in their pharmacological properties in various ways.
=== G04BD Drugs for urinary frequency and incontinence === G04BD01 Emepronium G04BD02 Flavoxate G04BD03 Meladrazine G04BD04 Oxybutynin G04BD05 Terodiline G04BD06 Propiverine G04BD07 Tolterodine G04BD08 Solifenacin G04BD09 Trospium G04BD10 Darifenacin G04BD11 Fesoterodine G04BD12 Mirabegron G04BD13 Desfesoterodine G04BD14 Imidafenacin G04BD15 Vibegron
== Ductal network == The ductal pancreas network originates from the central pancreatic duct—this main duct with the bile duct opens into the duodenum. The ductal cells of the main pancreatic duct are bound by connective tissue and produce a columnar epithelium. Interlobular ducts originate from the main pancreatic duct and connect the various pancreatic lobes. In these lobes, the intercalated ducts expel acini. Meanwhile, the ductal cells of these intercalated ducts create a simple squamous epithelium that rapidly converts into simple cuboidal epithelium, and connective tissue also surrounds them. As the ducts grow larger, the epithelium becomes cuboidal or columnar (when large in diameter, the ducts become stratified cuboidal), and connective tissue surrounds them. Pancreatic ductal cells are very similar to ductal cells of other exocrine glands (liver, bile duct, salivary glands). Because of this, a common diagnosis affects these cells: cystic fibrosis.
Sources: en.wikipedia.org
SR9009 is a synthetic compound investigated as an agonist of the nuclear receptors REV-ERBα and REV-ERBβ. It is used in preclinical research on circadian rhythm and metabolism. It is not an approved drug.
No. It has no approved medical indication, and human safety and efficacy data are limited. It appears in research chemical markets and is banned by some sports authorities.
Natural ligands include heme and certain metabolites; SR9009 is a synthetic small molecule with higher potency and selectivity in some assays. Its effects depend on cell type and timing. It is not a naturally occurring compound.
Research-grade SR9009 is typically stored frozen at about minus twenty degrees Celsius, protected from light and moisture. Stock solutions are often kept in aliquots to avoid repeated freeze-thaw cycles. Specific storage conditions should follow the supplier's documentation.