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Half Maximal Inhibitory Concentration
Half maximal inhibitory concentration (IC50) is a measure of the potency of a substance in inhibiting a specific biological or biochemical function. IC50 is a quantitative measure that indicates how much of a particular inhibitory substance (e.g. drug) is needed to inhibit, ''in vitro'', a given biological process or biological component by 50%. The biological component could be an enzyme, cell, cell receptor or microbe. IC50 values are typically expressed as molar concentration. IC50 is commonly used as a measure of antagonist drug potency in pharmacological research. IC50 is comparable to other measures of potency, such as EC50 for excitatory drugs. EC50 represents the dose or plasma concentration required for obtaining 50% of a maximum effect ''in vivo''. IC50 can be determined with functional assays or with competition binding assays. Sometimes, IC50 values are converted to the pIC50 scale. :\ce = -\log_ \ce Due to the minus sign, higher values of pIC50 indicate ex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IC50 Determination Illustration
The DSB Class ES is an electric multiple unit to be used by the Danish State Railways (DSB). The trains go by the name ''IC5'' and are constructed by Alstom in Poland and Germany. Overview History On April 12, 2021, DSB announced that it would be acquiring 100 trains from Alstom. The investment was worth 2.6 billion euros. In April 2022 the name of the train was revealed as ''IC5''. A month later in May 2022 the entry into service for the trains was delayed from December 2024 to mid 2025. On May 11, 2023, a mockup was revealed in Copenhagen. In November 2023 a second delay was announced, pushing back the entry into service all the way to 2027. Alstom and DSB received the Red Dot Design Award for the design of the IC5 on June 21, 2024. The first unit began testing at the Velim facility on September 1st, 2024. Design The IC5 uses a different bodyshell compared to the other Coradia Stream units such as NS' ICNG and Trentalia's Pop Pop or POP may refer to: Arts, entertainment, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adenosine Triphosphate
Adenosine triphosphate (ATP) is a nucleoside triphosphate that provides energy to drive and support many processes in living cell (biology), cells, such as muscle contraction, nerve impulse propagation, and chemical synthesis. Found in all known forms of life, it is often referred to as the "molecular unit of currency" for intracellular energy transfer. When consumed in a Metabolism, metabolic process, ATP converts either to adenosine diphosphate (ADP) or to adenosine monophosphate (AMP). Other processes regenerate ATP. It is also a Precursor (chemistry), precursor to DNA and RNA, and is used as a coenzyme. An average adult human processes around 50 kilograms (about 100 mole (unit), moles) daily. From the perspective of biochemistry, ATP is classified as a nucleoside triphosphate, which indicates that it consists of three components: a nitrogenous base (adenine), the sugar ribose, and the Polyphosphate, triphosphate. Structure ATP consists of three parts: a sugar, an amine base ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gnuplot
gnuplot is a command-line and GUI program that can generate two- and three-dimensional plots of functions, data, and data fits. The program runs on all major computers and operating systems (Linux, Unix, Microsoft Windows, macOS, FreeDOS, and many others). Originally released in 1986, its listed authors are Thomas Williams, Colin Kelley, Russell Lang, Dave Kotz, John Campbell, Gershon Elber, Alexander Woo "and many others." Despite its name, this software is not part of the GNU Project. Features gnuplot can produce output directly on screen, or in many formats of graphics files, including Portable Network Graphics (PNG), Encapsulated PostScript (EPS), Scalable Vector Graphics (SVG), JPEG and many others. It is also capable of producing LaTeX code that can be included directly in LaTeX documents, making use of LaTeX's fonts and powerful formula notation abilities. The program can be used both interactively and in batch mode using scripts. gnuplot can read data in multiple ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
C (programming Language)
C (''pronounced'' '' – like the letter c'') is a general-purpose programming language. It was created in the 1970s by Dennis Ritchie and remains very widely used and influential. By design, C's features cleanly reflect the capabilities of the targeted Central processing unit, CPUs. It has found lasting use in operating systems code (especially in Kernel (operating system), kernels), device drivers, and protocol stacks, but its use in application software has been decreasing. C is commonly used on computer architectures that range from the largest supercomputers to the smallest microcontrollers and embedded systems. A successor to the programming language B (programming language), B, C was originally developed at Bell Labs by Ritchie between 1972 and 1973 to construct utilities running on Unix. It was applied to re-implementing the kernel of the Unix operating system. During the 1980s, C gradually gained popularity. It has become one of the most widely used programming langu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Equilibrium Constant
The equilibrium constant of a chemical reaction is the value of its reaction quotient at chemical equilibrium, a state approached by a dynamic chemical system after sufficient time has elapsed at which its composition has no measurable tendency towards further change. For a given set of reaction conditions, the equilibrium constant is independent of the initial analytical concentrations of the reactant and product species in the mixture. Thus, given the initial composition of a system, known equilibrium constant values can be used to determine the Chemical equilibrium#Composition of a mixture, composition of the system at equilibrium. However, reaction parameters like temperature, solvent, and ionic strength may all influence the value of the equilibrium constant. A knowledge of equilibrium constants is essential for the understanding of many chemical systems, as well as the biochemical processes such as oxygen transport by hemoglobin in blood and acid–base homeostasis in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
LD50
In toxicology, the median lethal dose, LD50 (abbreviation for "lethal dose, 50%"), LC50 (lethal concentration, 50%) or LCt50 is a toxic unit that measures the lethal dose of a given substance. The value of LD50 for a substance is the dose required to kill half the members of a tested population after a specified test duration. LD50 figures are frequently used as a general indicator of a substance's acute toxicity. A lower LD50 is indicative of higher toxicity. The term LD50 is generally attributed to John William Trevan. The test was created by J. W. Trevan in 1927. The term semilethal dose is occasionally used in the same sense, in particular with translations of foreign language text, but can also refer to a sublethal dose. LD50 is usually determined by tests on animals such as laboratory mice. In 2011, the U.S. Food and Drug Administration approved alternative methods to LD50 for testing the cosmetic drug botox without animal tests. Conventions The LD50 is usually expres ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
EC50
] Half maximal effective concentration (EC50) is a measure of the concentration of a drug, antibody or toxicant which induces a stimulus–response model, biological response halfway between the baseline and maximum after a specified exposure time. More simply, EC50 can be defined as the ''concentration required to obtain a 50% ..effect'' and may be also written as sub>50. It is commonly used as a measure of a drug's potency, although the use of EC50 is preferred over that of 'potency', which has been criticised for its vagueness. EC50 is a measure of concentration, expressed in molar units (M), where 1 M is equivalent to 1 mol/ L. The EC50 of a ''graded'' dose response curve therefore represents the concentration of a compound where 50% of its maximal effect is observed. The EC50 of a ''quantal'' dose response curve represents the concentration of a compound where 50% of the population exhibit a response, after a specified exposure duration. For clarification, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Certain Safety Factor
The therapeutic index (TI; also referred to as therapeutic ratio) is a quantitative measurement of the relative safety of a drug with regard to risk of overdose. It is a comparison of the amount of a therapeutic agent that causes toxicity to the amount that causes the therapeutic effect. The related terms therapeutic window or safety window refer to a range of doses optimized between efficacy and toxicity, achieving the greatest therapeutic benefit without resulting in unacceptable side-effects or toxicity. Classically, for clinical indications of an approved drug, TI refers to the ratio of the dose of the drug that causes adverse effects at an incidence/severity not compatible with the targeted indication (e.g. toxic dose in 50% of subjects, TD) to the dose that leads to the desired pharmacological effect (e.g. efficacious dose in 50% of subjects, ED). In contrast, in a drug development setting TI is calculated based on plasma exposure levels. In the early days of pharmaceu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Michaelis–Menten Kinetics
In biochemistry, Michaelis–Menten kinetics, named after Leonor Michaelis and Maud Menten, is the simplest case of enzyme kinetics, applied to enzyme-catalysed reactions involving the transformation of one substrate into one product. It takes the form of a differential equation describing the reaction rate v (rate of formation of product (biology), product P, with concentration p) as a function of a, the concentration of the Enzyme substrate (biology), substrate A (using the symbols recommended by the IUBMB). Its formula is given by the Michaelis–Menten equation: : v = \frac = \frac V, which is often written as V_\max, represents the limiting rate approached by the system at saturating substrate concentration for a given enzyme concentration. The Michaelis constant K_\mathrm has units of concentration, and for a given reaction is equal to the concentration of substrate at which the reaction rate is half of V. Biochemical reactions involving a single substrate are often ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Affinity (pharmacology)
In biochemistry and pharmacology, a ligand is a substance that forms a complex with a biomolecule to serve a biological purpose. The etymology stems from Latin ''ligare'', which means 'to bind'. In protein-ligand binding, the ligand is usually a molecule which produces a signal by binding to a site on a target protein. The binding typically results in a change of conformational isomerism (conformation) of the target protein. In DNA-ligand binding studies, the ligand can be a small molecule, ion, or protein which binds to the DNA double helix. The relationship between ligand and binding partner is a function of charge, hydrophobicity, and molecular structure. Binding occurs by intermolecular forces, such as ionic bonds, hydrogen bonds and Van der Waals forces. The association or docking is actually reversible through dissociation. Measurably irreversible covalent bonding between a ligand and target molecule is atypical in biological systems. In contrast to the definition o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
William Prusoff
William Herman Prusoff (June 25, 1920 – April 3, 2011) was an American pharmacologist who was an early innovator in antiviral drugs, developing idoxuridine, the first antiviral agent approved by the FDA, in the 1950s, and co-developing (with Tai-shun Lin) stavudine, one of the earliest AIDS drugs, in the mid-1980s. Scientific career William Prusoff attended the University of Miami. After receiving his undergraduate degree in chemistry, he obtained his PhD from Columbia University and later completed his postdoctoral training in the laboratory of professor Arnold Welch at Case Western Reserve University. After Welch was recruited by Yale to head the Medical School's pharmacology department, Prusoff was invited to join the same department as an assistant professor and was subsequently promoted to the rank of professor. This relationship at Yale would span over the next 58 years, with William Prusoff becoming one of Yale's most well respected scientists and teachers. Pruso ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cheng Yung-chi
Yung-chi Cheng (traditional Chinese: 鄭永齊; pinyin: ''Zhèng Yǒngqí''; born December 29, 1944), also known as Tommy Cheng, is a Taiwanese-American pharmacologist. He is the Henry Bronson Professor of Pharmacology at Yale University, where he is the director of the Cheng laboratory at the Yale School of Medicine devoted to the study of antiviral drugs, and chairman of the Consortium for the Globalization of Chinese Medicine (CGCM). Early life and education Cheng was born in England on December 29, 1944, and later moved to Taiwan. After graduating from Tunghai University in 1966 with a Bachelor of Science (B.S.) in chemistry and biology, Cheng went to Canada and studied for a year at the University of Guelph. Because his wife was a graduate student at Brown University, Cheng decided to transfer to Brown and pursue graduate studies in the United States. He spent his first two years at Brown University studying medicine before earning a Ph.D. in biochemical pharmacology in 19 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
