Transient expression

Transient expression, more frequently referred to "transient gene expression", is the temporary expression of genes that are expressed for a short time after a nucleic acid, most frequently plasmid DNA encoding an expression cassette, has been introduced into eukaryotic cells. The majority of transient gene expressions are done with cultivated animal cells. The technique is also used in plant cells; however, the transfer of nucleic acids into these cells requires different methods than those with animal cells. In both plants and animals, transient expression should result in a time-limited use of transferred nucleic acids, since any long-term expression would be called "stable expression".
Methodology varies depending on the organism to transform. While plants can be transformed with a construct introduced into "Agrobacterium tumefaciens" via agroinfiltration or floral dip, most animal cells would require a viral vector. In human, the field of transient transformation advanced rapidly during the 2020-2021 covid-19 pandemic with major COVID-19_vaccines using either direct mRNA transfer into human or adenovirus vectors, with the RNA being expressed in the host human to produce spike proteins that induce an immune response.
Some fungi, like yeasts or zygomycota, are susceptible to transformation by dedifferentiating their hyphae to protoplasts and adding Cl2Ca 10–50 mM, Tris-HCl 10 mM, polyethylene glycol (40%) and the DNA construct (> 5µg/ml) to a 10^8 protoplast/ml solution. Under this pH condition, PEG acts as a binder, promoting protoplasts to clump together and trap introduced DNA strands. This process has a relatively high efficiency, despite the fact that eukaryotic cells have abundant exonucleases that degrade exogenous DNA.


Muscarinic acetylcholine receptor M2

The muscarinic acetylcholine receptor M2, also known as the cholinergic receptor, muscarinic 2, is a muscarinic acetylcholine receptor that in humans is encoded by the "CHRM2" gene. Multiple alternatively spliced transcript variants have been described for this gene.
Function.
Heart.
The M2 muscarinic receptors are located in the heart, where they act to slow the heart rate down to normal sinus rhythm after negative stimulatory actions of the parasympathetic nervous system, by slowing the speed of depolarization. They also reduce contractile forces of the atrial cardiac muscle, and reduce conduction velocity of the atrioventricular node (AV node). However, they have little effect on the contractile forces of the ventricular muscle, slightly decreasing force.
IQ.
A Dutch family study found that there is "a highly significant association" between the "CHRM2" gene and intelligence as measured by the Wechsler Adult Intelligence Scale-Revised. A similar association was found independently in the "Minnesota Twin and Family Study".
However, a larger 2009 study attempting to replicate this claim instead found no significant association between the "CHRM2" gene and intelligence.
Olfactory behavior.
Mediating olfactory guided behaviors (e.g. odor discrimination, aggression, mating).
Mechanism of action.
M2 muscarinic receptors act via a Gi type receptor, which causes a decrease in cAMP in the cell, generally leading to inhibitory-type effects. They appear to serve as autoreceptors.
In addition, they modulate muscarinic potassium channels. In the heart, this contributes to a decreased heart rate. They do so by the Gαi subunit of the G protein; Gαi opens K+ channels in the membrane of the cardiac myocytes, which causes an outward current of potassium, effectively hyperpolarizing the membrane, which slows down the heart rate.
Ligands.
Few highly selective M2 agonists are available at present, although there are several non-selective muscarinic agonists that stimulate M2, and a number of selective M2 antagonists are available.


Current Opinion in Biotechnology


HEARO RNA motif

HNH Endonuclease-Associated RNA and ORF (HEARO) RNAs conform to a conserved RNA structure that was identified in bacteria by bioinformatics. HEARO RNAs average roughly 300 nucleotides, which is comparable to the size of many ribozymes, which catalyze chemical reactions.
Multiple lines of non-experimental evidence suggest that HEARO RNAs form part of a mobile genetic element. HEARO RNAs contain an open reading frame (ORF) that usually codes for a protein containing an HNH endonuclease domain. Members of this family of endonucleases are often used by mobile genetic elements, such as group I and group II introns, to facilitate their replication. Several instances were detected of homologous sequences where only one sequence contains the HEARO element, suggesting that the HEARO element might have integrated into an ancestor of this sequence. Such cases also suggest that HEARO elements integrate 5′ to ATGA or GTGA sequences, although no other integration requirements were elucidated. Additional analysis was consistent with the hypothesis of self replication.
The Rfam model of HEARO RNAs uses only the region that is 5′ to the ORF. This region includes the bulk of the structure, but does not include a hairpin located 3′ to the ORF.


Gene product

A gene product is the biochemical material, either RNA or protein, resulting from expression of a gene. A measurement of the amount of gene product is sometimes used to infer how active a gene is. Abnormal amounts of gene product can be correlated with disease-causing alleles, such as the overactivity of oncogenes which can cause cancer.
A gene is defined as "a hereditary unit of DNA that is required to produce a functional product". Regulatory elements include:
These elements work in combination with the open reading frame to create a functional product. This product may be transcribed and be functional as RNA or is translated from mRNA to a protein to be functional in the cell.
RNA products.
RNA molecules that do not code for any proteins still maintain a function in the cell. The function of the RNA depends on its classification. These roles include:
Protein synthesis is aided by functional RNA molecules such as tRNA, which helps add the correct amino acid to a polypeptide chain during translation, rRNA, a major component of ribosomes (which guide protein synthesis), as well as mRNA which carry the instructions for creating the protein product.
One type of functional RNA involved in regulation are microRNA (miRNA), which works by repressing translation. These miRNAs work by binding to a complementary target mRNA sequence to prevent translation from occurring. Short-interfering RNA (siRNA) also work by negative regulation of transcription. These siRNA molecules work in RNA-induced silencing complex (RISC) during RNA interference by binding to a target DNA sequence to prevent transcription of a specific mRNA.
Protein products.
Proteins are the product of a gene that are formed from translation of a mature mRNA molecule. Proteins contain 4 elements in regards to their structure: primary, secondary, tertiary and quaternary. The linear amino acid sequence is also known as the primary structure. Hydrogen bonding between the amino acids of the primary structure results in the formation of alpha helices or beta sheets. These stable foldings are the secondary structure. The particular combination of the primary and secondary structures form the tertiary structure of a polypeptide. The quaternary structure refers to the way multiple chains of polypeptides fold together.
Protein functions.
Proteins have many different functions in a cell and the function may vary based on the polypeptides they interact with and their cellular environment. Chaperone proteins work to stabilize newly synthesized proteins. They ensure the new protein folds into its correct functional conformation in addition to making sure products do not aggregate in areas where they should not. Proteins can also function as enzymes, increasing the rate of various biochemical reactions and turning substrates into products. Products can be modified by attaching groups such as phosphate via an enzyme to specific amino acids in the primary sequence. Proteins can also be used to move molecules in the cell to where they are needed, these are called motor proteins. The shape of the cell is supported by proteins. Proteins such as actin, microtubules and intermediate filaments provide structure to the cell. Another class of proteins are found in plasma membranes. Membrane proteins can be associated with the plasma membrane in different ways, depending on their structure. These proteins allow the cell to import or export cell products, nutrients or signals to and from the extracellular space. Other proteins help the cell to perform regulatory functions. For example, transcription factors bind to DNA to help transcription of RNA.


Claudina Rodrigues-Pousada

Claudina Rodrigues-Pousada was a research student at the Gulbenkian Institute of Science until 1973 and at the (IBPC), Paris from 1973 to 1979 and Paris Diderot University. In 1979 she completed her PhD studies and in 1976 was employed by the Calouste Gulbenkian Foundation as an adjoint researcher at the Gulbenkian Institute of Science; in 1984 she was a Senior Researcher until 31 December 1999. In 2000 she moved to the Institute of Technology Chemical Biology as an Invited Full Professor where she launched the Genomics and Stress laboratory. She worked with yeast to examine how the fungi reacts to environmental stressors, such as Iron, Arsenic, and Nitric oxide, and thus how these stressors regulate cellular homeostasis.
Early life and Education.
Rodrigues-Pousada was born in 1941 in Tadim, Portugal, and died on 2 March 2021 in Lisbon.
She graduated from the University of Porto with a degree in Pharmacy in 1968, though she started in Mathematics. She was awarded her PhD in Biochemistry from the Institute of Physical and Chemical Biology.
Awards and Honors.
In 1994 She was elected as a member of EMBO.
In 2009 Dr. Rodrigues-Pousada was awarded her university's "Figure of the Year" award.
In 2010 She received the Seeds of Science award.
In 2011 She was elected a Fellow of the American Association for the Advancement of Science.


Connexon

In biology, a connexon, also known as a connexin hemichannel, is an assembly of six proteins called connexins that form the pore for a gap junction between the cytoplasm of two adjacent cells. This channel allows for bidirectional flow of ions and signaling molecules. The connexon is the hemichannel supplied by a cell on one side of the junction; two connexons from opposing cells normally come together to form the complete intercellular gap junction channel. However, in some cells, the hemichannel itself is active as a conduit between the cytoplasm and the extracellular space, allowing the transference of ions and small molecules lower than 1-2 KDa. Little is known about this function of connexons besides the new evidence suggesting their key role in intracellular signaling.
Connexons made of the same type of connexins are considered homomeric, while connexons made of differing types of connexins are heteromeric.
Structure.
Assembly.
The assembly of connexons begins with synthesis of connexins within the cell and ends with the formation of gap junction channel plaques on the cell membrane. The connexin subunit proteins that make up connexons are synthesized on the membranes of the cells endoplasmic reticulum. These subunits are then oligomerized, or combined with other smaller parts, into connexons in the golgi apparatus. The connexons are then delivered to their proper location on the plasma membrane. Connexons then dock with compatible connexons from the neighboring cell to form gap junction channel plaques. A large part of this process is mediated by phosphorylation of different enzymes and proteins, allowing and preventing interaction between certain proteins.
General.
Connexons contribute to the formation of gap junctions, and are an essential component of the electric synapses in neural pathways. In a single gap junction, connexons will assemble around an aqueous porous membrane, forming a hemi-channel that is composed of connexins. Connexins are the smaller protein molecules that make up connexons and play a crucial part to the formation of gap junctions. Structurally, connexins are made up of 4 alpha helical transmembrane domains connected by 2 extracellular loops and 1 cytoplasmic loop, while both N and C terminals reside intracellularly. Connexin types can be further differentiated by using their predicted molecular weight (ex: Connexin 43 is Cx 43 due to its molecular weight of 43 kDa). Connexons will form the gap junction by docking a hemi-channel to another hemi-channel in an adjacent cell membrane. During this phase, the formation of an intercellular channels spanning both of the plasma membranes, occurs. Subsequently, this process leads to a better understanding of how electric synapses are facilitated between neurons.
Degradation.
Connexon structure is degraded by its removal from the plasma membrane. Connexons will be internalized by the cell itself as a double membrane channel structure (due to the docking of hemi-channels). This is called internalization or endocytosis. Research suggests that gap junctions in general may be internalized using more than one method, but the best known and most studied would be that of clathrin-mediated endocytosis. In simple terms this process consists of a ligand binding to a receptor signaling for a certain part of the membrane to be coated in clathrin. This part of the membrane then buds into the cell forming a vesicle. Now present in the cell membrane, connexons will be degraded by lysosomal pathways. Lysosomes are able to break down the proteins of the connexon because they contain specific enzymes that are made specifically for this process. It is thought that ubiquitination signals degradation within the cell.
Cellular functions.
Properties.
The properties of individual connexin proteins determine the overall properties of the whole connexon channel. The permeability and selectivity of the channels is determined by its width as well as the molecular selectivity of connexins such as charge selectivity. Research shows connexons are particularly permeable to soluble second messengers, amino acids, nucleotides, ions and glucose. Channels are also voltage sensitive. The connexon channels have voltage-dependent gates that open or close depending on the difference in voltage between the interiors of the two cells. Gates can also show voltage sensitivity depending on the difference in voltage from the interior and exterior of the cell (i.e. membrane potential).
Modulation.
Communication between gap-junctions can be modulated/regulated in many ways. The main types of modulation are:
Overall functions.
Connexons play an imperative role in behavior and neurophysiology. Many of the details surrounding their pathological functions remain unknown as research has only begun recently. In the central nervous system (CNS), connexons play a major role in conditions such as epilepsy, ischemia, inflammation, and neurodegeneration. The molecular mechanism as to how connexons play a role in the conditions listed above has yet to be fully understood and is under further research. Along with their key role in the CNS, connexons are crucial in the functioning of cardiac tissues. The direct connection allows for quick and synchronized firing of neurons in the heart which explains the ability for the heart to beat quickly and change its rate in response to certain stimuli. Connexons also play an essential role in cell development. Specifically, their role in neurogenesis dealing with brain development as well as brain repair during certain diseases/pathologies and also assisting in both cell division as well as cell proliferation. The mechanism by which connexons aid in these processes is still being researched however, it is currently understood that this mechanism involves purinergic signaling (form of extracellular signaling mediated by purine nucleotides and nucleosides such as adenosine and ATP) and permeability to ATP. Other important roles of connexons are glucose sensing and signal transduction. Connexons cause changes in extracellular glucose concentrations affecting feeding/satiety behavior, sleep-wake cycles, and energy use. Further studies indicate that there is an increase in glucose uptake mediated by connexons (whose mechanism is still not fully understood) and under times of high stress and inflammation. Recent research also indicates that connexons may affect synaptic plasticity, learning, memory, vision, and sensorimotor gating.
Related diseases.
Some of the diseases associated with connexons are cardiovascular disease and diabetes, which is the inability of the body to produce insulin for glucose uptake by cells and degradation in the smaller units of connexons, called connexins, possibly leading to the onset of heart disease. Cardiovascular disease and diabetes, type I and II, affects similar locations within cells of the heart and pancreas. This location is the gap junction, where connexons facilitate rapid cell-to-cell interactions via electrical transmissions. Gap junctions are often present at nerve endings such as in cardiac muscle and are important in maintaining homeostasis in the liver and proper function of the kidneys. The gap junction itself is a structure that is a specialized transmembrane protein formed by a connexon hemichannel. Cardiovascular disease and possibly type I and II diabetes, are each associated with a major protein connexin that makes up the gap junction.
In cardiovascular disease, Cx43 (connexin 43), a subunit of a connexon, is a general protein of the gap junction stimulating cardio myocyte muscle cells of intercalated discs facilitating synchronized beating of the heart. In the occurrence of cardiovascular disease the Cx43 subunit begins to show signs of oxidative stress, the ability of the heart to counteract the buildup of harmful toxins due to age or diet leading to reduced vascular functions. Additionally, reduced Cx43 expression in vascular tissue, which plays a part in ventricular remolding and healing of wounds after a myocardial infarction, are present in structural heart disease. However, the mechanisms of Cx43 in the heart are still poorly understood. Overall, these changes in Cx43 expression and oxidant stress can lead to abnormalities in the coordinated beating of the heart, predisposing it to cardiac arrhythmias.
Connexons are also associated with both Type I and Type II diabetes. Cx36 (connexin 36) subunit mediates insulin excretion and glucose-induced insulin release from gap junctions of the liver and pancreas. Homeostasis in the liver and pancreatic organs are supported by an intricate system of cellular interactions called endocrine signaling. The secretion of hormones into the blood stream to target distant organs. However, endocrine signaling in the pancreas and liver operates along short distances in the cellular membrane by way of signaling pathways, ion channels, G-protein coupled receptors, tyrosine-kinase receptors, and cell-to-cell contact. The gap junctions in these tissues supported by endocrine signaling arbitrate intracellular signals between cells and larger organ systems by connecting adjacent cells to each other in a tight fit. The Tight fit of the gap junction is such that cells in the tissue can communicate more efficiently and maintain homeostasis. Thus the purpose of the gap junction is to regulate the passage of ions, nutrients, metabolites, second messengers, and small biological molecules. In diabetes the subsequent loss or degradation of Cx36 substantially inhibits insulin production in the pancreas and glucose in the liver which is vital for the production of energy for the entire body. A deficiency of Cx36 adversely affects the ability of the gap junction to operate within these tissues leading a reduction in function and possible disease. Similar symptoms associated with the loss or degradation of the gap junction have been observed in type II diabetes, however, the function of Cx36 in Type 1 and type II diabetes in humans is still unknown. Additionally, the Cx36 connexin is coded for by GJD2 gene, which has a predisposition on the gene locus for type II diabetes, and diabetic syndrome.


Ramachandran plot

In biochemistry, a Ramachandran plot (also known as a Rama plot, a Ramachandran diagram or a [φ,ψ] plot), originally developed in 1963 by G. N. Ramachandran, C. Ramakrishnan, and V. Sasisekharan, is a way to visualize energetically allowed regions for backbone dihedral angles ψ against φ of amino acid residues in protein structure. The figure on the left illustrates the definition of the φ and ψ backbone dihedral angles (called φ and φ' by Ramachandran). The ω angle at the peptide bond is normally 180°, since the partial-double-bond character keeps the peptide planar. The figure in the top right shows the allowed φ,ψ backbone conformational regions from the Ramachandran et al. 1963 and 1968 hard-sphere calculations: full radius in solid outline, reduced radius in dashed, and relaxed tau (N-Cα-C) angle in dotted lines. Because dihedral angle values are circular and 0° is the same as 360°, the edges of the Ramachandran plot "wrap" right-to-left and bottom-to-top. For instance, the small strip of allowed values along the lower-left edge of the plot are a continuation of the large, extended-chain region at upper left.
Uses.
A Ramachandran plot can be used in two somewhat different ways. One is to show in theory which values, or conformations, of the ψ and φ angles are possible for an amino-acid residue in a protein (as at top right). A second is to show the empirical distribution of datapoints observed in a single structure (as at right, here) in usage for structure validation, or else in a database of many structures (as in the lower 3 plots at left). Either case is usually shown against outlines for the theoretically favored regions.
Amino-acid preferences.
One might expect that larger side chains would result in more restrictions and consequently a smaller allowable region in the Ramachandran plot, but the effect of side chains is small. In practice, the major effect seen is that of the presence or absence of the methylene group at Cβ. Glycine has only a hydrogen atom for its side chain, with a much smaller van der Waals radius than the CH3, CH2, or CH group that starts the side chain of all other amino acids. Hence it is least restricted, and this is apparent in the Ramachandran plot for glycine (see Gly plot in gallery) for which the allowable area is considerably larger. In contrast, the Ramachandran plot for proline, with its 5-membered-ring side chain connecting Cα to backbone N, shows a limited number of possible combinations of ψ and φ (see Pro plot in gallery). The residue preceding proline ("pre-proline") also has limited combinations compared to the general case.
More recent updates.
The first Ramachandran plot was calculated just after the first protein structure at atomic resolution was determined (myoglobin, in 1960), although the conclusions were based on small-molecule crystallography of short peptides. Now, many decades later, there are tens of thousands of high-resolution protein structures determined by X-ray crystallography and deposited in the Protein Data Bank (PDB). Many studies have taken advantage of this data to produce more detailed and accurate φ,ψ plots (e.g., Morris "et al." 1992; Kleywegt & Jones 1996; Hooft "et al." 1997; Hovmöller "et al." 2002; Lovell "et al." 2003; Anderson "et al." 2005". Ting "et al." 2010).
The four figures below show the datapoints from a large set of high-resolution structures and contours for favored and for allowed conformational regions for the general case (all amino acids except Gly, Pro, and pre-Pro), for Gly, and for Pro. The most common regions are labeled: α for α helix, Lα for left-handed helix, β for β-sheet, and ppII for polyproline II. Such a clustering is alternatively described in the ABEGO system, where each letter stands for α (and 310) helix, right-handed β sheets (and extended structures), left-handed helixes, left-handed sheets, and finally unplottable cis peptide bonds sometimes seen with proline; it has been used in the classification of motifs and more recently for designing proteins.
While the Ramachandran plot has been a textbook resource for explaining the structural behavior of peptide bond, an exhaustive exploration of how a peptide behaves in every region of the Ramachandran plot was only recently published (Mannige 2017).
The Molecular Biophysics Unit at Indian Institute of Science celebrated 50 years of Ramachandran Map by organizing International Conference on Biomolecular Forms and Functions from 8–11 January 2013.
Related conventions.
One can also plot the dihedral angles in polysaccharides (e.g. with CARP;
Software.
See also PDB for a list of similar software.


Bromazolam

Bromazolam (XLI-268) is a benzodiazepine derivative which was first synthesised in 1976, but was never marketed. It has subsequently been sold as a designer drug, first being definitively identified by the EMCDDA in Sweden in 2016. It is the bromo instead of chloro analogue of alprazolam, and has similar sedative and anxiolytic effects. Bromazolam is a non subtype selective agonist at the benzodiazepine site of GABAA receptors, with a binding affinity of 2.81nM at the α1 subtype, 0.69nM at α2 and 0.62nM at α5.


Krzysztof Cios

Krzysztof J. Cios (born 1950) is a Professor and Chair of the Department of Computer Science, School of Engineering, Virginia Commonwealth University (VCU), located in Richmond, Virginia. His research is focused on machine learning, data mining, and biomedical informatics.
Biography.
Krzysztof J. Cios, a Polish-American computer scientist, was born in Dębica, Poland. He earned his M.S. degree in Electrical Engineering and his Ph.D. degree in Computer Science, both from the AGH University of Science and Technology, Kraków, Poland. Cios also earned his D.Sc. (habilitation) degree from the Polish Academy of Sciences, Warsaw and an M.B.A. degree from the University of Toledo, Ohio.
Cios first worked at the Tadeusz Kościuszko University of Technology, Kraków, and also the International Atomic Energy Agency, Vienna, Austria. After moving to the U.S. in the 1980s he worked at the Electrical Engineering and Computer Science Department at the University of Toledo (UT). At UT he co-founded Department of Bioengineering and served as its Acting Chair before moving to Colorado. He also worked as a Visiting Scientist at NASA Glenn Research Center, Cleveland, Ohio. He then served as Chair of the Computer Science and Engineering Department at the University of Colorado Denver where he was instrumental in starting its Ph.D. program in Computer Science and Information Systems and getting its first-ever ABET accreditation. While in Colorado, he consulted for Lockheed Martin and Raytheon companies and was Affiliated Professor of Computer Science at the University of Colorado Boulder, where he was advisor of two doctoral students. He has also worked as a Visiting Professor at the Complutense University of Madrid, Spain, and at the Muroran Institute of Technology, Japan. Currently he serves as Chair of the Computer Science Department at VCU. He started a dual Ph.D. degree program in computer science between VCU and the University of Cordoba (UCO), Spain; students who meet requirements of both universities and perform research at the other university earn two Ph.D. degrees: from VCU and UCO. He also serves as Director of Enterprise Informatics, Office of the Vice President for Research and Innovation.
Cios has co-authored three books and over 200 journal and conference papers. His main contributions are in the areas of machine learning, computational neuroscience, and data mining; his book on the latter subject was the first one published in the U.S. (1998) and his article on uniqueness of medical data mining is frequently cited. In the area of neuroinformatics, he co-defined with Kevin Staley (Harvard Medical School) and others a dynamic Synaptic Activity Plasticity Rule, which in contrast to other plasticity rules is continuous and dynamic as it uses actual post-synaptic potential function to modify connection strength between neurons. Some of the machine learning algorithms developed with his students, such as CAIM and ur-CAIM discretization algorithms and rule algorithms for single-instance (DataSqueezer), multiple-instance (mi-DS) and one-class (OneClass-DS) learning, became popular and were implemented in open-source software platforms.
During his academic career Cios has served as primary advisor to 15 Ph.D. students and 20 M.S. students. The former work at universities in the U.S. (one as endowed chair of data science), Australia, Thailand and Vietnam, as post-doctoral researchers at NIH, and at companies such as Google, NASA, General Motors, and Procter & Gamble.
His research has been funded by the National Institutes of Health, NASA, National Science Foundation, Colorado Institute of Technology, American College of Cardiology, Ohio Aerospace Institute, U.S. Air Force, and NATO.
Cios has been the recipient of the Norbert Wiener Outstanding Paper Award (Kybernetes), the University of Toledo Outstanding Faculty Research Award, the Neurocomputing Best Paper Award and the Fulbright Senior Scholar Award. Cios is listed by the Kosciuszko Foundation as one of the eminent scientists of Polish origin and ancestry, is a Foreign Member of the Polish Academy of Arts and Sciences, and a Fellow of the American Institute for Medical and Biological Engineering.


TauD protein domain

In molecular biology, TauD refers to a protein domain that in many enteric bacteria is used to break down taurine (2-aminoethanesulfonic acid) as a source of sulfur under stress conditions. In essence, they are domains found in enzymes that provide bacteria with an important nutrient.
Function.
This protein family consists of TauD/TfdA taurine catabolism dioxygenases. The "Escherichia coli" tauD gene is required for the utilization of taurine (2-aminoethanesulfonic acid) as a sulfur source and is expressed only under conditions of sulfate starvation. TauD is an alpha-ketoglutarate-dependent dioxygenase catalyzing the oxygenolytic release of sulfite from taurine. The 2,4-dichlorophenoxyacetic acid/alpha-ketoglutarate dioxygenase from "Burkholderia sp." (strain RASC) also belongs to this family. TfdA from "Ralstonia eutropha" (Alcaligenes eutrophus) is a 2,4-D monooxygenase.
Structure.
This structure has a number of alpha helices and beta sheets. PDB structure


Integrated DNA Technologies

Integrated DNA Technologies, Inc. (IDT), headquartered in Coralville, Iowa, is a supplier of custom nucleic acids, serving the areas of academic research, biotechnology, clinical diagnostics, and pharmaceutical development. IDT's primary business is the manufacturing of custom DNA and RNA oligonucleotides (oligos) for research applications.
Joseph A. Walder, M.D., Ph.D. (Northwestern University), founded Integrated DNA Technologies, Inc. in 1987 through a partnership with Baxter Healthcare Corporation at the University of Iowa Technology Innovation Center business incubator. In its first 10 years, IDT grew from a startup with 10 synthesizing machines to a small company with more than 500, shipping an average 75,000 custom oligos per day to more than 82,000 customers worldwide. In March 2018, IDT was acquired by Danaher Corporation for a reported $1.9 billion.
Mission.
IDT's mission is to enable discovery in biology and medicine. The company strives to achieve this by improving nucleic acid synthesis technology and developing new applications for the use of DNA- and RNA-based compounds. IDT's advanced synthesis group combines expertise in chemistry, molecular biology, and engineering to produce and purify complex nucleic acids of all kinds.
SciTools.
Synthetic oligonucleotides are used in various molecular biology applications, e.g., polymerase chain reaction (PCR), molecular beacons, microarrays, mutagenesis, RNAi, antisense and gene synthesis. Published bioinformatics algorithms can predict biophysical properties of oligonucleotides from their sequence and estimate oligonucleotide performance in specific assays, when used singly or together with other sequences. IDT's "SciTools" is a free online suite of computational software tools that enable molecular biologists to design, evaluate and make informed decisions about the properties of nucleic acid sequences. Instructions and help to each software tool can be found at the top of web input forms. The code is regularly updated when more accurate models and algorithms are published.
Certifications.
IDT earned its ISO 9001:2000 certification at its oligonucleotide production headquarters in 2005.
IDT earned its ISO 13485:2003 certification for its Quality Management System in 2008.


Nanodisc

A nanodisc is a synthetic model membrane system which assists in the study of membrane proteins. Nanodiscs are discoidal proteins in which a lipid bilayer is surrounded by molecules that are amphipathic molecules including proteins, peptides, and synthetic polymers. It is composed of a lipid bilayer of phospholipids with the hydrophobic edge screened by two amphipathic proteins. These proteins are called membrane scaffolding proteins (MSP) and align in double belt formation. Nanodiscs are structurally very similar to discoidal high-density lipoproteins (HDL) and the MSPs are modified versions of apolipoprotein A1 (apoA1), the main constituent in HDL. Nanodiscs are useful in the study of membrane proteins because they can solubilise and stabilise membrane proteins and represent a more native environment than liposomes, detergent micelles, bicelles and amphipols.
The art of making nanodiscs has progressed past using only the MSPs and lipids to make particles, leading to alternative strategies like peptide nanodiscs that use simpler proteins and synthetic nanodiscs that do not need any proteins for stabilization.
MSP nanodisc.
The original nanodisc was produced by apoA1-derived MSPs from 2002. The size and stability of these discs depend on the size of these proteins, which can be adjusted by truncation and fusion. In general, MSP1 proteins consist of one repeat, and MSP2s are double-sized.
Peptide nanodisc.
In peptide nanodiscs, the lipid bilayer is screened by amphipathic peptides instead of two MSPs. Peptide nanodiscs are structurally similar to MSP nanodiscs and the peptides also align in a double belt. They can stabilise membrane proteins, but have higher polydispersity and are structurally less stable than MSP nanodiscs. Recent studies, however, showed that dimerization and polymerization of the peptides make them more stable.
Synthetic/Native nanodisc.
Another way to mimic the native lipid membrane are synthetic polymers. Styrene-maleic acid co-polymers (SMAs) called SMALPs or Lipodisq and Diisobutylene-maleic acid (DIBMA) are such synthetic polymers (DIBMALPs). They can solubilize membrane proteins directly from cells or raw extract. They also have been used to study the lipid composition of several organisms. It was discovered that all synthetic polymers which contained a styrene and maleic acid group can solubilize proteins. These SMA nanoparticles have also been tested as possible drug delivery vehicle and for the study of folding, post-translational modifications and lipid interactions of membrane proteins by native mass spectrometry.


Biotechnology in India

Agencies of the Government of India concerned with the biotechnology industry include the Department of Biotechnology and the proposed Biotechnology Regulatory Authority of India.
Department of Biotechnology.
The Department of Biotechnology (DBT) is an Indian government department, under the Ministry of Science and Technology responsible for administering development and commercialization in the field of modern biology and biotechnology in India. It was set up in 1986.
Biotechnology Regulatory Authority of India.
The Biotechnology Regulatory Authority of India (BRAI) is a proposed regulatory body in India for uses of biotechnology products including genetically modified organisms (GMOs). The institute was first suggested under the Biotechnology Regulatory Authority of India (BRAI) draft bill prepared by the Department of Biotechnology in 2008. Since then, it has undergone several revisions.


Autophagy (journal)

Autophagy is a monthly peer-reviewed scientific journal covering all aspects of cell autophagy. It is published by Taylor & Francis and the editor-in-chief is Daniel J. Klionsky (University of Michigan).
Abstracting and indexing.
The journal is abstracted and indexed in:
According to the "Journal Citation Reports", the journal has a 2019 impact factor of 9.770.


Resident Evil (film series)

Resident Evil is an action-horror film series based on the Japanese video game franchise of the same name by Capcom. German studio Constantin Film bought the rights to adapt the series in January 1998. In 2001, Screen Gems acquired distribution rights and hired Paul W. S. Anderson as writer and director for "Resident Evil" (2002). Anderson continued as writer and producer for ' (2004) and ' (2007), and returned as the director for ' (2010), ' (2012), and "" (2016).
The films follow Alice (Milla Jovovich), a character created for the films. Alice is a former security specialist and covert operative who battles the Umbrella Corporation, whose bioweapons have triggered a zombie apocalypse. Characters from the games appear, including Claire Redfield, Jill Valentine, Ada Wong, Carlos Olivera, Chris Redfield, Leon S. Kennedy, Barry Burton and antagonists Albert Wesker, the head of Umbrella Corporation, and James Marcus, Umbrella's top virologist.
Despite all the instalments receiving mixed-to-negative reviews from critics, the "Resident Evil" film series is the highest-grossing film series based on a video game, having grossed over $1.2 billion worldwide. It is also the highest-grossing zombie film series, and was the highest-grossing horror film series .
Setting.
Raccoon City is depicted in the Anderson film series as a 21st-century cosmopolitan city with an infrastructure largely funded by the Umbrella Corporation. The first film features the Hive as a secret laboratory under the city. Housing more than 500 employees, the facility has an artificial intelligence, the Red Queen, controlling its security. The theft and deliberate release of the T-virus starts the chain of events depicted in the opening of the first film. Although the Hive is sealed off at the end of the film, it is reopened in "", the second film, by the Umbrella Corporation. Infected creatures spread out of the re-opened Hive into Raccoon City and Umbrella places the city under quarantine. In an attempt to stop the spread of the T-virus, Umbrella destroys Raccoon City with a nuclear missile near the end of the film. In it is revealed that this does not stop the virus from spreading; within five years the human race is on the verge of extinction, and the vast majority of the Earth is a barren wasteland crawling with zombies and mutated animals.
Instead of creating large sets for Raccoon City and the Hive, the film crew filmed on location at Toronto, Canada and Berlin, Germany. Due to the fictional city being located in the Midwestern United States, the film's director Paul Anderson chose Toronto to serve as the fictional city. In the third installment, Extinction, there is a brief shot of Racoon City: the camera zooms out from Raccoon city to a view of the Earth - in this shot, Racoon City is depicted somewhere in either Illinois, Indiana, Michigan, or Ohio. The city was filmed untouched; many of its prominent features, such as its city hall and the CN Tower, are visible. For the underground train station in the Hive, Anderson chose to film in the Berlin U-Bahn. He said the atmosphere of the underground labyrinth structure was conducive to the acting and promoted a sense of realism and mood in the production. "" features another Hive in Death Valley, which is used for the research of a cure to the T-virus and of the Tyrant Program.
Films.
"Resident Evil" (2002).
In January 1998, Constantin Film acquired the film rights to the "Resident Evil" franchise with Alan B. McElroy possibly writing the script. George A. Romero was hired by Sony Pictures and Capcom to direct and write "Resident Evil". His script was later rejected and he was ultimately dropped. While Romero's script was supported by a number of people from Capcom and Constantin, it was rejected by Constantin producer Bernd Eichinger, as well as Capcom producer Yoshiki Okamoto, who said that Romero was fired as his script was poor. Paul W. S. Anderson was hired by Sony Pictures to write a screenplay; in late 2000, Anderson was announced as director and writer. Anderson stated the film would not include any tie-ins with the video game series as "under-performing movie tie-ins are too common and "Resident Evil", of all games, deserved a good celluloid representation". In 2001, Milla Jovovich was cast as Alice, the protagonist of the film. By May 2001, Columbia TriStar was in final negotiations to acquire North American distribution rights to the film and budgeted it at $40 million.
In the film, the Umbrella Corporation operates a top-secret genetic research facility named The Hive. Located deep beneath Raccoon City, The Hive has been sealed by The Red Queen (the AI that controls the Hive) due to the release of the T-virus into the facility. The Red Queen kills every living thing in the facility to ensure that the T-virus doesn't reach the surface, but the T-virus reanimates them, transforming the humans into ravenous zombies and the animals into highly aggressive mutants. Alice (Milla Jovovich) was once a security operative working for the Corporation until her memory was wiped by the Red Queen's nerve gas. As the team attempts to escape The Hive, an Umbrella test subject, a huge monster called the Licker, escapes and pursues the team onto a train, which they use to leave the Hive. During this pursuit, two members of the group are killed, leaving only Alice and Matt; however, Matt obtains a deeply scratched arm from the licker in the start of the attack. When Alice and Matt reach the surface, Matt and Alice are separated and taken by an Umbrella hazmat unit, where Matt begins to genetically transform. Alice awakens from a coma to a ravaged Raccoon City after a T-virus outbreak.
"Resident Evil: Apocalypse" (2004).
The sequel to the first film began production in 2003 after the success of the first film. Anderson returned as the writer but, due to his work on "Alien vs. Predator", he did not direct the film. Alexander Witt took over the director's role.
In the film, the viral outbreak reaches the surface and in an effort to contain the infection, Major Timothy Cain seals all exits to and from Raccoon City. Among the people trapped in the city are Jill Valentine and her partner Peyton Wells. After Alice awakens from her coma, she rescues Jill and Peyton from a group of Licker monsters who escaped The Hive. They are then contacted by Dr. Charles Ashford, who claims to know of an evacuation point in the city in exchange for the rescue of his daughter Angela Ashford, who is trapped in Raccoon City. The group knows that Umbrella plans to incinerate Raccoon City to get rid of the T-virus. On their way to rescue Angela, Nemesis attacks the team after it is commanded by Cain to kill all S.T.A.R.S.(Special Tactics And Rescue Service) members. After Angela's rescue, they then make their way to the evacuation helicopter with Carlos Olivera, who has been dropped into Raccoon City and abandoned by Umbrella.
After Alice's confrontation with Cain and Nemesis, which leaves the latter two dead, the team flies away from Raccoon City as it is being "sanitized" by a nuclear bomb. The helicopter crashes in the Arklay Mountains. A wounded Alice is the only person found by an Umbrella search team. She is taken to the Detroit Umbrella research station. When Alice awakens, she escapes the facility and displays extraordinary powers. She is then driven away by Jill and Carlos, who are disguised as Umbrella employees. As they drive away, the Umbrella logo flashes in Alice's eyes and Isaacs states "Program ALICE Activated".
"Resident Evil: Extinction" (2007).
In November 2005, Screen Gems gained the rights for the third installment in the franchise, which was then subtitled "Extinction". Anderson returned as a writer and filming took place in Mexico. Russell Mulcahy was the director. The film was released on September 21, 2007.
In the film, the world has been consumed by the T-virus and Umbrella Corporation develops clones of Alice in the hope of finding one who displays Alice's powers. Elsewhere, Claire Redfield leads a convoy of survivors across the Nevada desert, including Raccoon City survivors Carlos Olivera and L.J. Wayne. Alice roams the country alone, staying off the grid. After accidentally destroying her motorcycle with her powers in a dream, she decides she must join Redfield’s convoy which had setup base nearby. When Alice arrives at their position she rescues them from a mob of attacking crows using her special telekinetic powers. The convoy, along with Alice, heads to Las Vegas to gather supplies so that they can reach Alaska in an effort to get to a place called Arcadia, which is thought to be a safe haven. While there, they are ambushed by a group of Umbrella Corporation's new super zombies created by Dr. Alexander Isaacs, which kill most of the convoy. L.J. was bitten before, but he hides his infection from the rest of the group; he then transforms and bites Olivera, amidst the ambush. Isaacs himself is bitten and in an effort to cure himself he injects himself with large doses of the anti-virus, which causes him to transform into a Tyrant, a towering creature with regenerative ability and psionic (psychic) powers similar to Alice's.
Alice, Claire and Carlos then locate a helicopter in Umbrella base and plan to use it for extraction of the survivors to Alaska. Olivera makes his last stand by sacrificing himself and plowing his truck into a horde of zombies, giving the rest some time to load the survivors into the helicopter. Claire and the remaining survivors head towards Alaska, while Alice stays behind to confront Isaacs. While searching the facility for Isaacs, she discovers that she was cloned. After Alice defeats Isaacs, she contacts Umbrella and warns them that she is coming for them and that she will be bringing "friends" with her to fight them.
"Resident Evil: Afterlife" (2010).
Before the third installment had been released, Constantin prepared to release a fourth entry. The film was set in Japan and filmed in 3D with the Fusion Camera System developed by James Cameron and Vince Pace for the 2009 film "Avatar". The film was written and directed by Paul W. S. Anderson.
Set after the events of "Extinction", Alice and her clones attack the Umbrella Headquarters in Tokyo. Wesker escapes and destroys the facility, killing the clones. Wesker is confronted by Alice aboard his helicopter. He injects Alice with a serum that removes her super-human abilities. The helicopter crashes, and only Alice is seen emerging from the rubble. After six months of a failed aerial search for other survivors, Alice heads toward the supposed location of Arcadia. She lands on an airfield in Alaska, where she finds Claire in a different state. Claire has an Umbrella controlling device attached to her chest and her memory has been wiped. Claire and Alice fly to Los Angeles, where they stumble on a prison wherein they meet Luther West and Chris Redfield, Claire's brother. The survivors explain that Arcadia is really a tanker off the coast that has been broadcasting a looped message and is picking up survivors. During an attempted escape, Alice, Claire and Chris are the only ones to emerge and they reach the tanker only to find it abandoned. Claire's memory begins to return when she remembers Umbrella workers attacking her group of survivors and moving them to the tanker. They learn that the ship is an Umbrella research facility, which is conducting experiments on the survivors. The three then meet Wesker, who has been granted super-human abilities due to the T-virus. After the fight, Alice transmits a message to survivors calling them to the tanker and hopes to create a new and true safe haven. As the film closes, a fleet of Umbrella Corporation gunships led by Valentine prepares to lead an assault on the survivors.
"Resident Evil: Retribution" (2012).
Written and directed by Anderson, "Retribution" was planned to be filmed back to back with the sixth installment, but Anderson decided to focus on the fifth film. Filming took place in Toronto, Ontario from mid-October to December 23, 2011. Colin Salmon who played One and Michelle Rodriguez who played Rain Ocampo in the first film returned. Oded Fehr, who portrayed Carlos Olivera in the second and third film, also returned. Three characters from the video games made their debut in the film series, Johann Urb as Leon S. Kennedy, Kevin Durand as Barry Burton, and Li Bingbing as Ada Wong. It was released internationally on September 14, 2012.
In the film, Alice awakens in an Umbrella base where she is interrogated by Valentine. During a power failure orchestrated by Ada Wong, Alice escapes from her cell and encounters her. Wong explains that Wesker plans to aid Alice's escape and battle the base's supercomputer Red Queen, in order to save what's left of mankind. Wesker has organized a team of freelance operatives to infiltrate the base and help Alice and Ada escape, including Leon S. Kennedy, Barry Burton, and Luther West. Along the way, Alice finds a clone of a girl named Becky. They also face clone versions of Carlos Olivera, One, and Rain Ocampo, who are all under the direction of Valentine. After Alice meets up with the rescue team, Valentine's soldiers catch up to them, resulting in a shootout that kills Burton, Olivera and One. Alice, West, Kennedy, and Becky reach the surface and are met by a submarine, from which Valentine, the clone Rain, and a captured Ada emerge. With new orders from the Red Queen to kill Alice, Valentine battles Alice while Rain fights Kennedy and West. Alice manages to remove the scarab device from Valentine, returning her back to normal. Alice joins Kennedy in defeating Rain. Alice, Ada, Becky, Leon, and Valentine travel to Wesker's base. Wesker injects Alice with the T-virus, returning her former superhuman powers in order to enact his plan, then tells her that she is responsible for saving the remaining humans from extinction.
"Resident Evil: The Final Chapter" (2016).
Anderson wrote and directed the sixth and final film in the series, subtitled "The Final Chapter", which was filmed in 2D and was post-converted to stereoscopic 3D. Milla Jovovich reprised her role as Alice, with only Shawn Roberts, Iain Glen and Ali Larter returning from previous entries as Albert Wesker, Dr. Isaacs and Claire Redfield, respectively. Continuing from the last film, Anderson expressed his desire for the final film to "come full circle", bringing back characters, themes and the environment of the Hive from the first movie. Filming was set to begin in South Africa in August 2014 but was delayed to the summer of 2015 due to Jovovich's pregnancy. Principal photography commenced on September 18, 2015 in South Africa.
Picking up three weeks after the events in "Resident Evil: Retribution", humanity is on its last legs after Alice is betrayed by Wesker in Washington D.C. Alice encounters the Red Queen, who tells her that she must return to where the nightmare began – Raccoon City, where the Umbrella Corporation has developed an airborne anti-virus which will kill every organism infected by the T-virus. In a race against time, Alice is captured by Dr. Isaacs, long thought to be dead, who reveals that the previous incarnation was a clone. Alice escapes and arrives first in Raccoon City, where she joins forces with Claire Redfield. After holding off Dr. Isaacs' undead army, Alice, Claire and a team of survivors make their way towards the Hive. They again encounter the Red Queen, who tells them the origins of the T-virus: it was created by James Marcus, the founder of the Umbrella Corporation to save his daughter, Alicia, from an ailment that caused her to age rapidly. James was betrayed by his business partner, Dr. Isaacs, and killed by Albert Wesker. Dr. Isaacs and the board of the Umbrella Corporation then intended to release the T-virus on purpose in order to cleanse the world, save the rich and powerful with cryogenics in The Hive, and later rebuild it as they desire.
After confronting Wesker and the real Dr. Isaacs at the bottom of the Hive, Alice also learns her own true nature: she is a clone of the still-living Alicia Marcus, who was unable to live a normal life due to her condition. Dr. Isaacs' clone brought the army of undead towards Alice and the real Dr. Isaacs. Dr. Isaacs' clone could not believe that he was a clone and stabbed the real Dr. Isaacs to death. Alice then releases the anti-virus, eliminating all infected by the T-virus. Alice survives, and gains the memories of Alicia Marcus as a reward in order to reclaim the childhood she never had. The series ends with Alice riding a motorcycle to New York City and places unknown while being chased by huge flying BOW's (bio organic weapons), stating that her job isn't finished yet and that it will take several years for the anti-virus to circle the globe.
The film was released on December 23, 2016 in Tokyo and on January 27, 2017 in North America.
"Resident Evil: Welcome to Raccoon City" (2021).
In May 2017, Constantin chairman Martin Moszkowicz said that a reboot of the series was in development.
In the same month, it was announced that James Wan would produce the reboot with a script by Greg Russo. In December 2018, Johannes Roberts was hired as writer/director and Wan left the project to helm a reboot of "Mortal Kombat".
In August 2019, The Level Unlocked Podcast first broke the news of the movie being developed and informed everyone using "Screen Rant" that the reboot would be "super, super scary" and more faithful to the games. In April 2020, Full Circle Cinema reported that the studio are eyeing Brenton Thwaites, Kaya Scodelario and Harris Dickinson for the roles of the Redfield siblings Chris and Claire and Leon S. Kennedy, and The Illuminerdi also reported that Hannah John-Kamen is being offered the role of Jill Valentine. On October 6, 2020, Deadline has reported that both Scodelario and Kamen are confirmed for Claire and Jill and announced that Robbie Amell, Tom Hopper, Avan Jogia and Neal McDonough are cast as Chris Redfield, Albert Wesker, Leon S. Kennedy and William Birkin. The reboot will also be an origin story and will be set in 1998. Filming began on October 17, 2020 in Sudbury, Ontario, Canada. The film is scheduled to be theatrically released on November 24, 2021 by Sony Pictures Releasing in the United States.
Cast and crew.
Principal cast.
List indicator(s)
Reception.
Box office performance.
With the exception of the first entry and "The Final Chapter", all films opened at number one at the North American box office. The series holds the record for the "most live-action film adaptations of a video game" in the 2012 "Guinness World Records Gamer's Edition". It is also the highest-grossing film series to be based on a video game, grossing more than worldwide.
Critical and public response.
"The Chicago Tribune" declared the first film as "one of the few video game movies to truly re-create the gaming experience" and "The Austin Chronicle" calling it "an absolute wreck. But what an ambitiously mind-blowing wreck it is, bursting with dazzlingly sordid cinematography". "The Seattle Times" marked the second film an improvement from the original, saying the film "makes up for the wretched mess that was 2002's "Resident Evil"". "The Hollywood Reporter" gave the third film a positive review stating "Fast-paced and filled with brisk action sequences—the film should reasonably satisfy the devotees." Michael Ordoña of "The Los Angeles Times" gave the fourth film a positive review, claiming that "the action is easier to read than in most films of the genre, and therefore more enjoyable. Anderson makes particular use of sets and locations to wring out more bang for the stereoscopic buck."
Home media.
Sony Pictures Home Entertainment has released all six films on DVD, Blu-ray, and digital download. The films were also released in DVD, Blu-Ray and 4K box sets:
Other media.
Novelizations.
The novelizations for the first three "Resident Evil" films were written by Keith R. A. DeCandido. The novelization for the fifth film was written by John Shirley, and the sixth by Tim Waggoner. The fourth film did not receive a novelization.
The novel for the first film, titled "Resident Evil: Genesis", was published over two years after that film's release, while the "Extinction" novel was released in late July 2007, two months before the film's release. There was also a Japanese novelization of the first film, unrelated to DeCandido's version, written by Osamu Makino. Makino also wrote two novels based on the game "".


PKM2

Pyruvate kinase isozymes M1/M2 (PKM1/M2), also known as pyruvate kinase muscle isozyme (PKM), pyruvate kinase type K, cytosolic thyroid hormone-binding protein (CTHBP), thyroid hormone-binding protein 1 (THBP1), or opa-interacting protein 3 (OIP3), is an enzyme that in humans is encoded by the "PKM2" gene.
PKM2 is an isoenzyme of the glycolytic enzyme pyruvate kinase. Depending upon the different metabolic functions of the tissues, different isoenzymes of pyruvate kinase are expressed. PKM2 is expressed in some differentiated tissues, such as lung, fat tissue, retina, and pancreatic islets, as well as in all cells with a high rate of nucleic acid synthesis, such as normal proliferating cells, embryonic cells, and especially tumor cells.
Structure.
Two isozymes are encoded by the "PKM" gene: PKM1 and PKM2. The M-gene consists of 12 exons and 11 introns. PKM1 and PKM2 are different splicing products of the M-gene (exon 9 for PKM1 and exon 10 for PKM2) and solely differ in 23 amino acids within a 56-amino acid stretch (aa 378-434) at their carboxy terminus.
Function.
Pyruvate kinase catalyzes the last step within glycolysis, the dephosphorylation of phosphoenolpyruvate to pyruvate, and is responsible for net ATP production within the glycolytic sequence. In contrast to mitochondrial respiration, energy regeneration by pyruvate kinase is independent from oxygen supply and allows survival of the organs under hypoxic conditions often found in solid tumors.
The involvement of this enzyme in a variety of pathways, protein–protein interactions, and nuclear transport suggests its potential to perform multiple nonglycolytic functions with diverse implications, although multidimensional role of this protein is as yet not fully explored. However, a functional role in angiogenesis the so-called process of blood vessel formation by interaction and regulation of Jmjd8 has been shown.
Localization.
Tissue.
The PKM1 isozyme is expressed in organs that are strongly dependent upon a high rate of energy regeneration, such as muscle and brain.
Cellular.
PKM2 is enzyme pyruvate kinase M2 (PKM2) and a transcriptional coactivator of STAT1 responsible for the induction of the protein PDL-1expression and its regulation in tumor and immune cells. In the lactate production, the upregulated PKM2 is required and it leads to its contribution in inflammatory response, organ injury and septic death As a consequence, the removal of PKM2 in myeloid cells, administration of anti-PD-L1 or supplementation with recombinant interleukin -1 (IL-7)  eases the microbial clearance, inhibits T cell apoptosis, reduce multiple organ dysfunction and reduce septic death in Bmal1-deficient mice.
Subcellular.
PKM2 is a cytosolic enzyme that is associated with other glycolytic enzymes, i.e., hexokinase, glyceraldehyde 3-P dehydrogenase, phosphoglycerate kinase, phosphoglyceromutase, enolase, and lactate dehydrogenase within a so-called glycolytic enzyme complex.
However, PKM2 contains an inducible nuclear localization signal in its C-terminal domain. The role of PKM2 within the nucleus is complex, since pro-proliferative but also pro-apoptotic stimuli have been described. On the one hand, nuclear PKM2 was found to participate in the phosphorylation of histone 1 by direct phosphate transfer from PEP to histone 1. On the other hand, nuclear translocation of PKM2 induced by a somatostatin analogue, H2O2, or UV light has been linked with caspase-independent programmed cell death.
Clinical significance.
Bi-functional role within tumors.
PKM2 is expressed in most human tumors. Initially, a switch from PKM1 to PKM2 expression during tumorigenesis was discussed. These conclusions, however, were the result of misinterpretation of western blots that had used PKM1-expressing mouse muscle as the sole non-cancer tissue. In clinical cancer samples, solely an up-regulation of PKM2, but no cancer specificity, could be confirmed.
In contrast to the closely homologous PKM1, which always occurs in a highly active tetrameric form and which is not allosterically regulated, PKM2 may occur in a tetrameric form but also in a dimeric form. The tetrameric form of PKM2 has a high affinity to its substrate phosphoenolpyruvate (PEP), and is highly active at physiological PEP concentrations. When PKM2 is mainly in the highly active tetrameric form, which is the case in differentiated tissues and most normal proliferating cells, glucose is converted to pyruvate under the production of energy. Meanwhile, the dimeric form of PKM2 is characterized by a low affinity to its substrate PEP and is nearly inactive at physiological PEP concentrations. When PKM2 is mainly in the less active dimeric form, which is the case in tumor cells, all glycolytic intermediates above pyruvate kinase accumulate and are channelled into synthetic processes, which branch off from glycolytic intermediates such as nucleic acid-, phospholipid-, and amino acid synthesis. Nucleic acids, phospholipids, and amino acids are important cell building-blocks, which are greatly needed by highly proliferating cells, such as tumor cells.
Due to the key position of pyruvate kinase within glycolysis, the tetramer:dimer ratio of PKM2 determines whether glucose carbons are converted to pyruvate and lactate under the production of energy (tetrameric form) or channelled into synthetic processes (dimeric form). However, even if PKM2 activity is low leading to the diversion of upstream intermediates to synthetic processes, pyruvate and lactate will still be made using carbon atoms from glucose and other metabolites through 86 pathways bypassing pyruvate kinase. These pyruvate kinase bypassing pathways are different than those participating in gluconeogenesis. Interestingly, many of the pyruvate kinase bypassing pathways use metabolites that transit through mitochondria, highlighting the importance of mitochondria in cancer metabolism irrespective of oxidative phosphorylation.
In tumor cells, PKM2 is mainly in the dimeric form and has, therefore, been termed Tumor M2-PK. The quantification of Tumor M2-PK in plasma and stool is a tool for early detection of tumors and follow-up studies during therapy. The dimerization of PKM2 in tumor cells is induced by direct interaction of PKM2 with different oncoproteins (pp60v-src, HPV-16 E7, and A-Raf). The physiological function of the interaction between PKM2 and HERC1 as well as between PKM2 and PKCdelta is unknown). Due to the essential role of PKM2 in aerobic glycolysis (The Warburg effect) which is a dominant metabolic pathway used by cancer cells. Its overcome in this pathway in macrophages may lead to better outcome in experimental sepsis. Thus, PKM2 is a regulator of LPS- and tumor-induced PD-L1 expression on macrophages and dendritic cells as well as tumor cells.
However, the tetramer:dimer ratio of PKM2 is not stationary value. High levels of the glycolytic intermediate fructose 1,6-bisphosphate induce the re-association of the dimeric form of PKM2 to the tetrameric form. As a consequence, glucose is converted to pyruvate and lactate with the production of energy until fructose 1,6-bisphosphate levels drop below a critical value to allow dissociation to the dimeric form. This regulation is termed "metabolic budget system". Another activator of PKM2 is the amino acid serine. The thyroid hormone 3,3´,5-triiodi-L-thyronine (T3) binds to the monomeric form of PKM2 and prevents its association to the tetrameric form.
In tumor cells, the increased rate of lactate production in the presence of oxygen is termed the Warburg effect. Genetic manipulation of cancer cells so that they produce adult PKM1 instead of PKM2 reverses the Warburg effect and reduces the growth rate of these modified cancer cells. Accordingly, cotransfection of NIH 3T3 cells with gag-A-Raf and a kinase dead mutant of PKM2 reduced colony whereas cotransfection with gag-A-Raf and wild type PKM2 led to a doubling of focus formation.
The dimeric form of PKM2 has been observed to have protein kinase activity in tumor cells. It is able to bind to and phosphorylate the histone H3 of chromatin in cancer cells, thereby having a role in the regulation of gene expression. This modification of histone H3 and the resulting involvement in gene expression regulation can be a cause of tumor cell proliferation.
The pyruvate kinase activity of PKM2 can be promoted by SAICAR (succinylaminoimidazolecarboxamide ribose-5′-phosphate), an intermediate in purine biosynthesis. In cancer cells, glucose starvation leads to a rise in SAICAR levels and the subsequent stimulation of pyruvate kinase activity of PKM2. This allows for the completion of the glycolytic pathway to produce pyruvate and, therefore, survival under glucose deprivation. In addition, an abundance of SAICAR can modify glucose absorption and lactate production in cancer cells. However, it has been shown that SAICAR binding also sufficiently stimulates the protein kinase activity of PKM2 in tumor cells. In turn, the SAICAR-PKM2 complex can potentially phosphorylate a number of other protein kinases using PEP as the phosphate donor. Many of these proteins contribute to the regulation of cancer cell proliferation. Specifically, PKM2 can be a component in mitogen-activated protein kinase (MAPK) signaling, which is associated with increased cell proliferation if functioning improperly. This provides a potential link between SAICAR-activated PKM2 and cancer cell growth.
Natural mutations and carcinogenesis.
Two missense mutations, H391Y and K422R, of PKM2 were found in cells from Bloom syndrome patients prone to developing cancer. Results show that, despite the presence of mutations in the inter-subunit contact domain, the K422R and H391Y mutant proteins maintained their homotetrameric structure, similar to the wild-type protein, but showed a loss of activity of 75 and 20%, respectively. H391Y showed a 6-fold increase in affinity for its substrate phosphoenolpyruvate and behaved like a non-allosteric protein with compromised cooperative binding. However, the affinity for phosphoenolpyruvate was lost significantly in K422R. Unlike K422R, H391Y showed enhanced thermal stability, stability over a range of pH values, a lesser effect of the allosteric inhibitor Phe, and resistance toward structural alteration upon binding of the activator (fructose 1,6-bisphosphate) and inhibitor (Phe). Both mutants showed a slight shift in the pH optimum from 7.4 to 7.0. The co-expression of homotetrameric wild type and mutant PKM2 in the cellular milieu resulting in the interaction between the two at the monomer level was substantiated further by in vitro experiments. The cross-monomer interaction significantly altered the oligomeric state of PKM2 by favoring dimerisation and heterotetramerization. In silico study provided an added support in showing that hetero-oligomerization was energetically favorable. The hetero-oligomeric populations of PKM2 showed altered activity and affinity, and their expression resulted in an increased growth rate of Escherichia coli as well as mammalian cells, along with an increased rate of polyploidy. These features are known to be essential to tumor progression.
Further, cells stably expressing exogenous wild- or mutant-PKM2 (K422R or H391Y) or co-expressing both wild and mutant (PKM2-K422R or PKM2-H391Y), were assessed for cancer metabolism and tumorigenic potential. Cells co-expressing PKM2 and mutant (K422R or H391Y) showed significantly aggressive cancer metabolism, compared to cells expressing either wild or mutant PKM2 independently. A similar trend was observed for oxidative endurance, tumorigenic potential, cellular proliferation and tumor growth. These observations signify the dominant negative nature of these mutations. Remarkably, PKM2-H391Y co-expressed cells showed a maximal effect on all the studied parameters. Such a dominant negative impaired function of PKM2 in tumor development is not known; also evidencing for the first time the possible predisposition of BS patients with impaired PKM2 activity to cancer, and the importance of studying genetic variations in PKM2 in future to understand their relevance in cancer in general.
Regulatory circuits.
Cancer cells are characterized by a reprogramming of energy metabolism. Over the last decade, understanding of the metabolic changes that occur in cancer has increased dramatically, and there is great interest in targeting metabolism for cancer therapy. PKM2 plays a key role in modulating glucose metabolism to support cell proliferation. PKM2, like other PK isoforms, catalyzes the last energy-generating step in glycolysis, but is unique in its capacity to be regulated. PKM2 is regulated on several cellular levels, including gene expression, alternative splicing and post-translational modification. In addition, PKM2 is regulated by key metabolic intermediates and interacts with more than twenty different proteins. Hence, this isoenzyme is an important regulator of glycolysis and additional functions in other novel roles that have recently emerged. Recent evidence indicates that intervening in the complex regulatory network of PKM2 has severe consequences on tumor cell proliferation, indicating the potential of this enzyme as a target for tumor therapy.
Bacterial pathogenesis.
With the yeast two-hybrid system, gonococcal Opa proteins were found to interact with PKM2. The results suggest that direct molecular interaction with the host metabolic enzyme PKM2 is required for the acquisition of pyruvate and for gonococcal growth and survival.


David Nachmansohn

David Nachmansohn (17 March 1899 – 2 November 1983) was a German-Jewish biochemist responsible for elucidating the role of phosphocreatine in energy production in the muscles, and the role of the neurotransmitter acetylcholine in nerve stimulation. He is also recognised for his basic research into the biochemistry and mechanism underlying bioelectric phenomena.
He was born in Ekaterinoslav, Russia (now Dnipro, Ukraine), moving to Berlin at an early age. In 1926 he went to the Kaiser-Wilhelm Institut für Biologie where he worked in the laboratory under Otto Meyerhof. Nachmansohn discovered that rapidly contracting muscles contained more phosphocreatine than slowly contracting ones, which eventually led to the hypothesis that phosphocreatine was involved in the regeneration of the ATP that was built up to provide energy during muscular contraction.
Leaving Nazi-era Berlin, Nachmansohn arrived in Paris in 1933 and took up a position in the Sorbonne. There he discovered that acetylcholinesterase is present at high concentrations in many different types of excitable nerve and muscle fibres and in brain tissue - lending support for Otto Loewi and Henry Dale's then novel proposal that acetylcholine functions in the transmission of impulses from nerves across junctions to other nerves or to muscles.
Nachmansohn obtained very active solutions of acetylcholinesterase from the electric organ of the marbled electric ray ("Torpedo marmorata"). Nachmansohn moved to Yale University in 1939 and while there published studies confirming the presence of even higher concentration of acetylcholinesterase in the electric organ of electric eels ("Electrophorus electricus"). This work also demonstrated a strong connection between the release of acetylcholine and the electric discharge.
In 1942 Nachmansohn moved into a laboratory at Columbia University where his group continued to publish on the mechanism underlying electric discharge in fish; using electric eels provided by the aquarium of the New York Zoological Society.
David Nachmansohn was elected member of Leopoldina in 1963 and became a member of the National Academy of Sciences (USA) in 1965. He was made an Honorary Fellow of the Weizmann Institute in 1972.


Isometheptene

Isometheptene (usually as isometheptene mucate) is a sympathomimetic amine sometimes used in the treatment of migraines and tension headaches due to its vasoconstricting properties; that is, it causes constriction (narrowing) of blood vessels (arteries and veins). Along with paracetamol and dichloralphenazone, it is one of the constituents of Amidrine.
Chemistry.
Isometheptene is a monounsaturated aliphatic secondary amine.
Mechanism of action.
Isometheptene's vasoconstricting properties arise through activation of the sympathetic nervous system via epinephrine and norepinephrine. These compounds elicit smooth muscle activation leading to vasoconstriction by interacting with cell surface adrenergic receptors.


Ophthalmic acid

Ophthalmic acid, also known as ophthalmate (chemically -γ-glutamyl--α-aminobutyrylglycine), is a tripeptide analog of glutathione in which the cysteine group is replaced by -2-aminobutyrate. It was first discovered and isolated from calf lens.
Biosynthesis.
Recent studies have shown that the ophthalmate can be biologically synthesized from 2-amino butyric acid through consecutive reactions with gamma-glutamylcysteine synthetase and glutathione synthetase. So the ophthalmic acid could be used as a biomarker in oxidative stress where the depletion of glutathione takes place.


Acetrizoic acid

Acetrizoic acid is a pharmaceutical drug that was used as an iodinated contrast medium for X-ray imaging. It was applied in form of its salt, sodium acetrizoate, but is no longer in clinical use.
Chemistry and mechanism of action.
The substance has high osmolality and is water-soluble. The three iodine atoms in the molecule readily absorb X-rays and are therefore responsible for its usability as a contrast medium.
History.
Acetrizoate was developed by V.H. Wallingford of Mallinckrodt, and introduced in 1950; it was employed as a contrast agent for several radiographic studies, including pyelography, angiography of the brain, carotid arteries and the aorta, and cholecystography. It was soon found to be highly toxic to the kidneys and nervous system—work urging caution in its administration was published as early as 1959, after reports of adverse reactions ranging from hypersensitivity to brain damage—and was eventually replaced by other agents with higher efficacy and lower toxicity, such as sodium diatrizoate, a closely related compound.
Trade names.
Trade names include Urokon, Triurol and Salpix, as well as Gastrografina and Urografina in Portugal.


Sir John Guise, 2nd Baronet

Sir John Guise, 2nd Baronet (c.1654 – November 1695) of Elmore Court, Gloucestershire was an English landowner and Member of Parliament.
Life.
He was born the only son of Sir Christopher Guise, 1st Baronet of the Elmore baronets of Gloucestershire and educated at Christ Church, Oxford, where he matriculated in 1669. He then travelled in France for a while. He succeeded his father to the baronetcy and to Elmore Court in 1670.
He acted as a local Justice of the Peace and as a Deputy-Lieutenant of Gloucestershire (?1674-81, 1689-death). He was Mayor of Gloucester for 1690–91 and Vice-Admiral of Gloucestershire from 1691 to his death.
He was elected the Member of Parliament for Gloucestershire in February 1679, August 1679 and 1681 but defeated in the election of 1685 by the Court party candidate and forced to take refuge in the Netherlands. He returned in 1688 with William of Orange and then took part in the capture of Bristol as Colonel of a foot regiment. Re-elected for Gloucestershire to the Convention Parliament of 1689 he was an active member, serving on many committees. Re-elected again in 1690 and 1695 he died in office shortly after his final election.
Private life.
He died of smallpox in November 1695 and was buried in St John the Baptist church, Elmore. He had married, in 1674, Elizabeth, the daughter of John Grobham Howe of Little Compton, Withington, Gloucestershire, a previous MP for the county. He and Elizabeth had a son and 2 daughters. He was succeeded by his son John.


Medroxalol

Medroxalol is a vasodilator beta blocker also classified as a mixed receptor blocker as it blocks both alpha and beta receptors.
Synthesis.
For the first step, salicylamide (1) is the subject of a Friedel-Crafts acetylation and then the aromatic methylketone is halogenated. in the usual manner. The bromide in 2 is then displaced by the nitrogen in "N"-benzyl-1-(3',4'-methylenedioxyphenyl)-3-butylamine (3), which is itself prepared by reductive amination on the corresponding ketone. The product of the last step (4) is catalytically hydrogenated. This serves the dual purpose both of reducing the ketone and removing the benzyl protecting group affording the product medroxalol (5). Note that a benzyl protecting group is not necessarily used.
See also.
Labetalol


RNA extraction

RNA extraction is the purification of RNA from biological samples. This procedure is complicated by the ubiquitous presence of ribonuclease enzymes in cells and tissues, which can rapidly degrade RNA. Several methods are used in molecular biology to isolate RNA from samples, the most common of these is guanidinium thiocyanate-phenol-chloroform extraction. The filter paper based lysis and elution method features high throughput capacity.
RNA extraction in liquid nitrogen, commonly using a mortar and pestle (or specialized steel devices known as tissue pulverizers) is also useful in preventing ribonuclease activity.
RNase contamination.
The extraction of RNA in molecular biology experiments is greatly complicated by the presence of ubiquitous and hardy RNases that degrade RNA samples. Certain RNases can be extremely hardy and inactivating them is difficult compared to neutralizing DNases. In addition to the cellular RNases that are released there are several RNases that are present in the environment. RNases have evolved to have many extracellular functions in various organisms. For example, RNase 7, a member of the RNase A superfamily, is secreted by human skin and serves as a potent antipathogen defence. For these secreted RNases, enzymatic activity may not even be necessary for the RNase's exapted function. For example, immune RNases act by destabilizing the cell membranes of bacteria.
To counter this, equipment used for RNA extraction is usually cleaned thoroughly, kept separate from common lab equipment and treated with various harsh chemicals that destroy RNases. For the same reason, experimenters take special care not to let their bare skin touch the equipment.
External links.
Two-phase wash to solve the ubiquitous contaminant-carryover problem in commercial nucleic-acid extraction kits; by Erik Jue, Daan Witters & Rustem F. Ismagilov; Nature, Scientific reports, 2020.


Renucleation

Renucleation technology.
It is a new type of embryonic culture enables scientists to transfer a fertilized nucleus of an ovum ( with diploid number 2n) into unfertilized one after destroying its nucleus using radiation. and replaced by a nucleus of embryonic cell of another individual
Process.
When the fertilized ovum is transplanted to the mother's ovary it develops into a normal individual which has gained its characters from the parents (source of the 2n nucleus).
This proves that the early embryonic cell nucleus is capable to direct the embryonic development in a manner similar to that of the zygote nucleus itself


KN-02 Toksa

The KN-02 Toksa (), Hwasong-11 is a North Korean reverse-engineered locally produced modification of the OTR-21 Tochka short-range ballistic missile.
Design and development.
In 1983, Syria acquired a number of 9K79 Tochka (SS-21 Scarab-A) missiles from the Soviet Union, a single-stage, solid-propellant guided missile with a range of 70 km and a CEP of 160 m. In 1996, Syrian missile technicians provided North Korea with technical data on the missiles, then shipped some of the missiles themselves. The first test of a North Korean-produced version occurred in April 2004 and was a failure, but it was then successfully fired on 1 May 2005 into the Sea of Japan; the KN-02 has been tested at least 17 times. Initial production is believed to have begun in 2006, with the missile displayed aboard a launcher during a military parade in April 2007, and entering service in 2008. At least 50 missiles are speculated to be in service.
The KN-02 is a short-range, road-mobile ballistic missile, broadly equivalent to improved Scarab-B. Although it has a shorter range than other North Korean missiles like the Scud-C, it has superior accuracy of near 100 meters CEP through inertial guidance with an optical correlation system in the terminal phase, making it the most accurate ballistic missile in the inventory; this enables it to be used for precision strikes against priority targets such as airfields, command posts, bridges, storage facilities, and even enemy troops concentrations in a tactical support role on the battlefield. Its warhead weighs and likely consists of a high-explosive, submunition, thermonuclear, chemical payload; Russian engineers could equip the OTR-21 with a 100 kiloton nuclear warhead. The missile has a range of , and it may be capable of traveling through reducing payload to .
A significant difference between the Russian OTR-21 and North Korean KN-02 is the transporter erector launcher (TEL). While the Russian missile is transported and fired from the 6×6 9P129 that has amphibious capabilities, the KN-02's TEL is a locally fabricated version of the Belarusian MAZ-630308-224 or -243 6×4 or 6×6 commercial heavy utility truck, which has a maximum road speed of and is not amphibious. The vehicle has a short firing cycle, able to be ready for launch in 16 minutes, launch the missile in 2 minutes, and be reloaded in 20 minutes by a supporting reloader vehicle of the same design fitted with a crane and holding 2-4 more missiles.
Further developments.
In 2013, South Korean intelligence reports suggested that North Korea was developing an anti-ship ballistic missile version of the KN-02. Its range is estimated to be , longer than current KN-01 variants, and it would be much more difficult to intercept due to its faster speed.
In March 2014, a South Korean military source claimed that the KN-02's range had been extended to through improved engine performance. The source also claimed that North Korea possessed 100 missiles with 30 TELs deployed to fire them. In August 2014, three KN-02s were fired out to a range of and estimated to have 100 meter circular error probable accuracy.
Extended range Hwasong-11/KN-02 is referred to as KN-10. It is expected that range of the missile is greater than 230 kilometers.
The U.S. identified the KN-10 system back in 2010.
See also.
OTR-21 Tochka


Vesosome

A vesosome is a multi-compartmental structure of lipidic nature used to deliver drugs. They can be considered multivesicular vesicles (MVV) and are, therefore, liposome derived structures.
Description.
Vesosomes consist of one or more bilayers enclosing an aqueous core that contains unilamellar vesicles that function as internal compartments which contain the drug and which can vary in composition from each other.
The external bilayer defines the lumen, limits emission of the vesicle contents, and protects the vesicle contents from degradation due to lipolytic enzymes.
Its unique properties enable localized drug delivery to specific parts of the body and extend the duration of drug effect. Vesosomes are relatively straightforward to produce and they offer the flexibility to deliver multiple drugs within a single carrier, which has been shown to confer important advantages in chemotherapy.
Internal vesicle diameters range from 20-500 nm and vesosome diameters range from about 0.1 micron to more than 1.0 micron.
Historical background.
Shortly after the first description of liposomes, by British haematologist Dr Alec D Bangham in 1961 (published 1964), at the Babraham Institute, in Cambridge, scientists first started to contemplate the possibility of employing them as transportation systems in the blood stream. Since then, there have been many advances in this area, and as of 2008 there were 11 clinically approved liposomal drugs targeting a variety of pathological conditions and illnesses, including fungal infections, hepatitis A, influenza and certain cancers. Now, scientists plan to take full advantage of the 40 years of progress in liposome development to enhance this transportation system by employing vesosomes.
Design and Construction.
Vesosome multicompartment structure encapsulates unilamellar liposomes within a second bilayer. For this purpose, it is necessary to form bilayers that can be opened and closed at will, without disrupting the inner content. This is achieved by adding ethanol to a variety of saturated phospholipids in the gel phase, which drives interdigitation of phospholipids bilayers and subsequent fusion of small vesicles to form flat bilayer sheets. These are steady to removal of the residual ethanol until heated above the lipid chain melting temperature (Tm). The bilayers become flexible, and the sheets spontaneously close on themselves to form unilamellar vesicles. During the closure, the sheets can entrap whatever is around in suspension. By adding the vesicles aggregates including drug-loaded vesicles to the pelleted sheets before heating the mixture, encapsulation is carried out to form vesosomes.
Vesosome structure has taken advantage of the progress in liposome development as steric stabilization, pH loading of drugs (it is loaded by pH gradient), and intrinsic biocompatibility (it can be modified with a variety of agents, for example to specifically target a disease site, or promote adhesion or fusion).
Applications.
A wide of molecular structures can be encapsulated in vesosomal vesicles, such as proteins with complex three-dimensional structures or condensed DNA. The most common use is to fill the vesosome’s vesicles with certain drugs that are going to be delivered in a particular area.
Due to the small size of the vesosome and its good protection of the inner vesicles, it can be used in various cases, doing different functions.
If suitable receptors are included in the outer lipid bilayer of vesosomes during their preparation, then they are able to locate to inflamed areas. Once in the inflamed area, such vesosomes will deliver an anti-inflammatory substance from its vesicles though a pH gradient. Vesosomes that localise to tumours have also been demonstrated.
They can be used to create, in a positioned area, a different nano-environment (considering that vesosome size is about 50 - 200 nanometres) either by altering the pH or the concentration of a particular substance.


Patrick Purdon

Patrick Lee Purdon, Ph.D., is an American biomedical engineer whose research focuses on neuroscience, neuroengineering, and clinical applications. He holds the Nathaniel M. Sims Endowed Chair in Anesthesia Innovation and Bioengineering at Massachusetts General Hospital and is an Associate Professor of Anaesthesia at Harvard Medical School. Dr. Purdon received his Ph.D. in Biomedical Engineering from Massachusetts Institute of Technology in 2005. His research in neuroengineering encompasses the mechanisms of anesthesia, Alzheimer’s disease and brain health, anesthesia and the developing brain, neural signal processing, and the development of novel technologies for brain monitoring. He has published over 90 peer-reviewed publications, is an inventor on 16 pending patents, and is a Fellow of the American Institute for Medical and Biological Engineering. Dr. Purdon has won many awards, including the prestigious National Institutes of Health Director’s New Innovator Award, and his work has been covered in the popular media, including programs on Radiolab and NPR.
Biography.
Purdon was born in Hong Kong and grew up in Chula Vista, California. During high school, he was a finalist in the Westinghouse Science Talent SearchRegeneron Science Talent Search, and was a National Merit Scholar, and the valedictorian of Chula Vista High School. Purdon studied Engineering Sciences at Harvard College and received his A.B. (summa cum laude) in 1996. He attended MIT for his graduate studies, within the Harvard-MIT Division of Health Sciences and Technology Medical Engineering and Medical Physics (MEMP) programHarvard–MIT Program of Health Sciences and Technology. For his Master’s thesis, he worked under the supervision of Drs. Robert Weisskoff and Victor Solo at the Martinos Center for Biomedical Imaging to develop novel signal processing methods for functional magnetic resonance imaging (fMRI) data analysis. He earned an S.M. degree in Electrical Engineering and Computer Science from MIT in 1998. In 1999, he joined the Neuroscience Statistics Research Laboratory directed by Dr. Emery Brown to study the neural mechanisms of anesthesia-induced unconsciousness in humans using simultaneous electroencephalography (EEG) and fMRI. Purdon was jointly supervised by Dr. Giorgio Bonmassar, with whom he developed novel technologies for simultaneous EEG-fMRI recordings during high-field MRI. Purdon received his Ph.D. in Biomedical Engineering at MIT in 2005.
Dr. Purdon joined the faculty at Harvard Medical School and Massachusetts General Hospital in 2005. In 2017, he was appointed as the first incumbent of the Nathaniel M. Sims Endowed Chair in Anesthesia Innovation and Bioengineering at Massachusetts General Hospital. He is also currently an Associate Professor of Anaesthesia at Harvard Medical School.
Scientific Contributions.
Neural Mechanisms of Anesthesia.
Dr. Purdon and his collaborators have been working on characterizing the neural mechanisms of anesthesia. In 2009, Purdon received a NIH Director’s New Innovator Award to develop a neural systems approach for monitoring and drug administration for general anesthesia. Using a multiscale and multimodal approach in humans, Purdon and his team discovered that anesthetics produce prominent, highly structured neural oscillations that disrupt brain activity. This profound disruption of brain activity is thought to be a primary mechanism by which anesthetic drugs produce unconsciousness. The form of these oscillations correspond to the underlying molecular mechanisms of different anesthetic drugs, leading to the concept that different anesthetic drug classes have distinct “EEG signatures” that relate to their mechanisms of action. His work incorporates animal models, computational models, and human studies.
Anesthesia-induced Brain Oscillations in Aging and Development.
Anesthetic drugs at brain circuits that change significantly during aging in adults and during development in children. Dr. Purdon and colleagues have shown that anesthesia-induced brain oscillations change significantly during aging and early childhood in a manner that likely reflects underlying brain aging and development. Purdon and colleagues are currently investigating how brain oscillations, anesthesia-induced or otherwise, could be used to better understand brain circuit function in humans during aging, Alzheimer’s disease, development, and developmental disorders.
Clinical Education.
Dr. Purdon lectures to an international audience about the use of EEG-based brain monitoring to guide anesthesia care. He and his team have also developed online educational programming in collaboration with the International Anesthesia Research Society, available at .
Neural Signal Processing.
Dr. Purdon has worked throughout his career to develop novel statistical signal processing methods for neuroscience. He has focused considerable effort on the EEG source localization problem, in which high-density scalp measurements are used to estimate underlying cerebral currents. His approach uses biophysical, functional neuroanatomic, and computational principles to guide the solution to this problem. His work has illustrated how neurophysiologically-principled models of sparsity, connectivity, and dynamics can significantly expand the realm of what is possible using source localization, improving spatial resolution significantly, and enabling localization of subcortical activity.
Awards and Honor.
Dr. Purdon's work has won many awards and has been featured on high-impact academic medium. For example, he received the National Institutes of Health Director's New Innovator Award from the National Institutes of Health in 2009, Hornorable Mention of MGH Martin Prize from the Massachusetts General Hospital in 2013, the Innovation Development Grant Award from Partners Healthcare in 2014, Best in Neuroscience Award from the Society for Neuroscience in Anesthesiology and Critical Care in 2015, the Art of Talking Science competition winner from the Massachusetts General Hospital Research Institute in 2016, and an author and participant invitation to the Manifestations and Mechanisms of Dynamic brain Coordination over Development in 2017.
Dr. Purdon also fellow and member of several professional organizations, including the Society for Neuroscience, the American Society of Anesthesiologists, the Institute of Electrical and Electronics Engineers (IEEE), the International Anesthesia Research Society (IARS), the American Institute for Medical and Biological Engineering (AIMBE), the Society for Neuroscience in Anesthesiology and Critical Care, and the Association of University Anesthesiologists (AUA).
Music.
Dr. Purdon is also a jazz vocalist who performs regularly in the Boston area.


Bunazosin

Bunazosin (INN) is an alpha 1 antagonist. Bunazosin was initially developed to treat benign prostatic hyperplasia (BPH). It has been approved in Japan in a topical form to treat glaucoma. The mechanism of action is a reduction of aqueous outflow through the uveoscleral pathway resulting in lowering the intraocular pressure. It also may act to improve blood flow to the ocular nerve. Systemic Alpha-1 adrenergic receptor antagonists have been implicated in Intraoperative Floppy Iris Syndrome (IFIS). Bunazosin potentially could have the same effect but there has been no research to substantiate this as a risk for cataract surgery.


Kathryn R. Nightingale

Kathryn Radabaugh Nightingale is an American biomedical engineer in the field of medical ultrasound. She is the Theo Pilkington Professor of Biomedical Engineering at Duke University in Durham, North Carolina. Nightingale is also a Member of the Duke Cancer Institute and Bass Fellow in the Duke University Pratt School of Engineering.
Education.
Nightingale graduated magna cum laude with her bachelor's degree in electrical engineering from the Duke University Pratt School of Engineering in 1989. In 1997, she obtained a Doctorate of Philosophy in biomedical engineering from the Duke University Graduate School of Arts at Sciences. Nightingale's thesis was entitled "Ultrasonic Generation and Detection of Acoustic Streaming to Differentiate between Fluid-Filled and Solid Lesions in the Breast".
College athletics.
As a freshman, Nightingale was a member of the 1985-86 Duke Blue Devils women's basketball team, and made the Atlantic Coast Conference Honor Roll for that year.
Career.
Research interests.
Nightingale's early work focused on acoustic streaming to differentiate fluid filled cysts and solid masses in the breast, which was the precursor to acoustic radiation force impulse (ARFI) imaging when it was determined that acoustic radiation force could induce displacements in soft tissue.
Nightingale's research interests center around ultrasound and elasticity imaging. She is specifically interested in acoustic streaming, acoustic radiation force, and nonlinear acoustics, especially for tissue characterization. She uses finite element modeling as well as phantom and clinical experiments to investigate these phenomena. Nightingale's clinical imaging interests include abdominal imaging, prostate imaging and muscle imaging.
Professional societies.
Nightingale is a member of many professional and academic societies and advisory boards.
Professional committees.
Nightingale has sat and sits on several professional committees.
Conference and review panels.
Nightingale has sat on several grant review panels and has chaired several conference sessions.


Phycourobilin

Phycourobilin is an orange tetrapyrrole involved in photosynthesis in cyanobacteria and red algae. This chromophore is bound to the phycobiliprotein phycoerythrin, the distal component of the light-harvesting system of cyanobacteria and red algae (phycobilisome).
When bound to phycoerythrin, phycourobilin shows an absorption maximum around 495 nm. This chromophore is always a donor chromophore of phycoerythrins, since their acceptor chromophore is always phycoerythrobilin. It can also be linked to the linker polypeptides of the phycobilisome, in which its precise role remains unclear.
Phycourobilin is found in marine phycobilisome containing organisms, allowing them to efficiently absorb blue-green light. In the ubiquitous marine cyanobacteria "Synechococcus", the amount of phycourobilin in the phycobilisomes is correlated to the ecological niche the cells inhabit: offshore "Synechococcus" are quite phycourobililin-rich, while coastal "Synechococcus" contain very little or no phycourobilin. This represents a remarkable adaptation of the cyanobacterial light-harvesting system, as oceanic waters are relatively richer in blue light than onshore waters.


Sulfur carrier protein ThiS adenylyltransferase

Sulfur carrier protein ThiS adenylyltransferase (, "thiF (gene)") is an enzyme with systematic name "ATP:(ThiS) adenylyltransferase". This enzyme catalyses the following chemical reaction
This enzyme binds Zn2+. The enzyme catalyses the adenylation of ThiS, a sulfur carrier protein involved in the biosynthesis of thiamine.


Indanidine

Indanidine is an alpha-adrenergic agonist.