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Topic Review
Marie-Anne Libert
Marie-Anne Libert, (born 7 April 1782 in Malmedy, province of Liège, died 14 January 1865 in Malmedy) was a Belgian botanist and mycologist. She was one of the first women plant pathologists. She is sometimes referred to as "Anne-Marie Libert."
  • 571
  • 08 Oct 2022
Topic Review
Optic Pit
Optic pit, optic nerve pit, or optic disc pit (ODP) is rare a congenital excavation (or regional depression) of the optic disc (also optic nerve head), resulting from a malformation during development of the eye. The incidence of ODP is 1 in 10,000 people with no predilection for either gender. There is currently no known risk factors for their development. Optic pits are important because they are associated with posterior vitreous detachments (PVD) and even serous retinal detachments.
  • 569
  • 19 Oct 2022
Topic Review
Task Allocation and Partitioning of Social Insects
Task allocation and partitioning is the way that tasks are chosen, assigned, subdivided, and coordinated within a colony of social insects. Task allocation and partitioning gives rise to the division of labor often observed in social insect colonies, whereby individuals specialize on different tasks within the colony (e.g., "foragers", "nurses"). Communication is closely related to the ability to allocate tasks among individuals within a group. This entry focuses exclusively on social insects. For information on human task allocation and partitioning, see division of labour, task analysis, and workflow.
  • 562
  • 20 Oct 2022
Topic Review
Ulcerative Gingivitis
Acute necrotizing ulcerative gingivitis (ANUG) is a common, non-contagious infection of the gums with sudden onset. The main features are painful, bleeding gums, and ulceration of inter-dental papillae (the sections of gum between adjacent teeth). This disease, along with necrotizing (ulcerative) periodontitis (NP or NUP) is classified as a necrotizing periodontal disease, one of the seven general types of gum disease caused by inflammation of the gums (periodontitis). The often severe gum pain that characterizes ANUG distinguishes it from the more common chronic periodontitis which is rarely painful. If ANUG is improperly treated or neglected, it may become chronic and/or recurrent. The causative organisms are mostly anaerobic bacteria, particularly Fusobacteriota and spirochete species. Predisposing factors include poor oral hygiene, smoking, poor nutrition, psychological stress, and a weakened immune system. When the attachments of the teeth to the bone are involved, the term NUP is used. Treatment of ANUG is by removal of dead gum tissue and antibiotics (usually metronidazole) in the acute phase, and improving oral hygiene to prevent recurrence. Although the condition has a rapid onset and is debilitating, it usually resolves quickly and does no serious harm. The informal name trench mouth arose during World War I as many soldiers developed the disease, probably because of the poor conditions and extreme psychological stress.
  • 557
  • 11 Oct 2022
Topic Review
Antagonistic Coevolution
Sexual antagonistic co-evolution is the relationship between males and females where sexual morphology changes over time to counteract the opposite's sex traits to achieve the maximum reproductive success. This has been compared to an arms race between sexes. In many cases, male mating behavior is detrimental to the female's fitness. For example, when insects reproduce by means of traumatic insemination, it is very disadvantageous to the female's health. During mating, males will try to inseminate as many females as possible, however, the more times a female's abdomen is punctured, the less likely she is to survive. Females that possess traits to avoid multiple matings will be more likely to survive, resulting in a change in morphology. In males, genitalia is relatively simple and more likely to vary among generations compared to female genitalia. This results in a new trait that females have to avoid in order to survive. Additionally, sexual antagonistic co-evolution can be the cause of rapid evolution, as is thought to be the case in seminal proteins known as Acps in species of Drosophila melanogaster. While Acps facilitate the mutually beneficial outcome of increased progeny production, several Acps have detrimental effects on female fitness as they are toxic and shorten her lifespan. This leads to antagonistic co-evolution, as the female must evolve in order to defend herself. When female Drosophila melanogaster are experimentally prevented from co-evolving with males, males rapidly adapt to the static female phenotype. This male adaptation leads to a reduction in female survivorship, which is mediated by an increased rate of remating and increased toxicity of Acps in seminal fluid. Since non-reproductive proteins do not feel the same evolutionary pressure as Acps, they are not evolving nearly as quickly. Consistent with the arms race theory, DNA analyses reveal a two-fold increase in Acp divergence relative to non-reproductive proteins
  • 537
  • 19 Oct 2022
Topic Review
Type A Influenza Vaccine
Type A influenza vaccine is for the prevention of infection of influenza A virus and also the influenza-related complications. Different monovalent type A influenza vaccines have been developed for different subtypes of influenza A virus including H1N1 and H5N1. Both intramuscular injection or intranasal spray are available on market. Unlike the seasonal influenza vaccines which are used annually, they are usually used during the outbreak of certain strand of subtypes of influenza A. Common adverse effects includes injection site reaction and local tenderness. Incidences of headache and myalgia were also reported with H1N1 whereas cases of fever has also been demonstrated with H5N1 vaccines. It is stated that immunosuppressant therapies would reduce the therapeutic effects of vaccines and that people with egg allergy should go for the egg-free preparations. There are different methods in developing the vaccines. Traditionally, inactivated viral vaccine and live attenuated virus vaccine have been approved. Inactivated viral vaccine is primary used parentally and the live attenuated vaccine is used intranasally. Development of new technologies including the recombinant hemagglutinin technology have widely been studied. Influenza A virus was successfully identified and isolated by Wilson Smith, Christopher Andrewes, and Patrick Laidlaw in the 1930s and the first inactivated monovalent influenza A vaccine was made after a decade. The first H5N1 vaccine was approved in 2007. It was intentionally developed to prepare for the possible H5N1 outbreak in the future. Moreover, in view of the H1N1 outbreak in 2009, H1N1 monovalent vaccines, targeting only H1N1 virus, was produced. Influenza A exists in many subtypes including H5N1, H1N1 and H3N2. Different formulations of monovalent vaccines have been developed over the years to cater different needs and antigens identified.
  • 534
  • 11 Oct 2022
Topic Review
Integrating Text-Mining into the Curation of Disease Maps
The interactive, user-friendly disease map viewer was developed to support the automated creation of systems medicine models such as disease maps by text mining. It sits at the interface between computational text mining and the manual expert creation of disease maps, was developed to sit at the interface between computational text mining and the manual expert creation and brings together the time-saving advantages of text mining with the accuracy of manual data curation.
  • 506
  • 20 Sep 2022
Topic Review
Biochemical Recurrence in High-Risk Localized Prostate Cancer
This retrospective study compared oncological outcomes in 107 patients with localized prostate cancer treated between 2016–2023 by either laparoscopic radical prostatectomy (LRP; n=61) or external beam radiotherapy with androgen deprivation therapy (EBRT+ADT; n=46). Median follow-up was 60 months for LRP and 66 months for EBRT. Biochemical recurrence (BCR) was defined as PSA > 0.2 ng/mL post-LRP or > 2 ng/mL above nadir post-EBRT. BCR occurred in 34.4% of LRP and 21.7% of EBRT patients. Five-year BCR-free survival was 65.6% (LRP) vs. 71.7% (EBRT), with a trend favoring EBRT (log-rank p = 0.089). Median time to recurrence was 30 months (LRP) and 48 months (EBRT). In the LRP group, higher ISUP grade (p = 0.001), advanced pathological stage (p < 0.001), positive surgical margins (p < 0.001), and intermediate PSA levels (10–20 ng/mL; p = 0.080) predicted BCR. No independent predictors were found in the EBRT group. Both treatments offered effective cancer control, but LRP had a higher recurrence risk, especially in patients with intermediate-risk features. These findings support risk-adapted follow-up and timely salvage therapy in high-risk LRP patients.
  • 295
  • 01 Jul 2025
Topic Review Peer Reviewed
Anthropology in One Health
Anthropology in One Health refers to the use of anthropological concepts, methods and field-based approaches to analyse health problems at the intersections of humans, animals, plants, microbes and environments. It examines how disease, risk, care, surveillance and prevention are understood, negotiated and organised in specific social and ecological settings. Its contribution is not simply to add a “social dimension” to biological problems already defined elsewhere. It also asks how a health problem is framed in the first place, whose observations are recognised as evidence, and how different ways of describing a situation shape the interventions that become possible. In this entry, One Health is approached primarily as a collaborative field of practice rather than as a single theoretical concept, bringing together ethnography, medical anthropology, political ecology, multispecies approaches, ethnobiology and studies of Indigenous and local knowledge.
  • 34
  • 17 Sep 2026
Topic Review Peer Reviewed
Tethered Swimming: Historical Notes and Future Prospects
Swimming coaches know that a swimmer’s assessment must be specific and ecological. Thus, it is critical to select and employ adequate methodologies. The tethered swimming method can be useful and valid, in addition to being simple to apply. Regular use of this methodology can give coaches tools to intervene with their swimmers and increase performance. The main objective of this manuscript was to analyze the potential for measuring the propulsive forces exerted in water as a biomechanical tool for evaluating and training competitive swimmers. The key results demonstrated that this methodology allows (i) the assessment of upper limb bilateral kinetic asymmetries; (ii) the evaluation of the contribution of the upper and lower limb actions, inferring about the (un)balance between strength and coordination; (iii) the examination of the relationship between the intracyclic variations in speed and force; (iv) the evaluation of the effective application of force to the speed of high-level swimmers. Furthermore, this manuscript suggests advances using mathematical modeling and artificial intelligence (AI) that will provide significant insights into swimming performances. AI developments will promote its integration into sports optimization, and swimming will be no exception.
  • 16
  • 29 Apr 2026
Topic Review
Flavonoid Biosynthesis
Flavonoid biosynthesis is a multi-enzyme metabolic pathway in plants that produces flavonoids, a large class of polyphenolic secondary metabolites characterized by a C6–C3–C6 carbon skeleton [1]. The pathway originates from the phenylpropanoid branch of primary metabolism, in which the amino acid phenylalanine is converted to cinnamic acid by phenylalanine ammonia-lyase (PAL), subsequently hydroxylated by cinnamate-4-hydroxylase (C4H) and activated to p-coumaroyl-CoA by 4-coumarate-CoA ligase (4CL) [2]. The committed step of flavonoid biosynthesis is catalyzed by chalcone synthase (CHS), a type III polyketide synthase that condenses p-coumaroyl-CoA with three molecules of malonyl-CoA to yield naringenin chalcone, the foundational scaffold for all flavonoid subclasses [3]. Chalcone isomerase (CHI) then catalyzes the intramolecular cyclization of chalcone to the flavanone naringenin, from which the pathway diverges into multiple branches through the action of downstream enzymes including flavonoid 3′-hydroxylase, flavonoid 3′,5′-hydroxylase, flavanone 3-hydroxylase, dihydroflavonol 4-reductase, anthocyanidin synthase, and anthocyanidin reductase. These enzymatic steps generate the eight major flavonoid branches—stilbene, aurone, flavone, isoflavone, flavonol, phlobaphene, proanthocyanidin, and anthocyanidin—each distinguished by specific hydroxylation, methylation, glycosylation, and oxidation patterns [1]. The pathway is subject to multilayered transcriptional regulation, primarily mediated by MYB–bHLH–WD40 transcription factor complexes that coordinate tissue-specific, developmental, and environmentally responsive expression of structural genes [4]. Genomic analyses have revealed that flavonoid biosynthetic genes have evolved through gene duplication and functional divergence, with enzyme families such as cytochrome P450 monooxygenases, short-chain dehydrogenases/reductases, and 2-oxoglutarate-dependent dioxygenases acquiring specialized roles in modifying the flavonoid scaffold [5].
  • 7
  • 23 Sep 2026
Topic Review
Steroid Biosynthesis
Steroid biosynthesis is the set of enzyme-catalyzed metabolic pathways that generate sterols and their steroid-derived products from isoprenoid precursors. In the canonical eukaryotic pathway, acetyl-coenzyme A is converted through the mevalonate pathway into activated isoprene units, which are condensed to form squalene; squalene epoxidation and oxidosqualene cyclization then establish the tetracyclic sterol nucleus [1][2]. Subsequent reactions—including demethylation, reduction, oxidation, isomerization, side-chain modification, and hydroxylation—produce lineage-specific membrane sterols, such as cholesterol, phytosterols, or ergosterol, and, where present, downstream steroidal metabolites [2][3]. In animals, steroid biosynthesis also encompasses the conversion of cholesterol into steroid hormones through compartmentalized reactions involving cholesterol side-chain cleavage, hydroxylation, dehydrogenation, and related transformations catalyzed principally by cytochrome P450 enzymes and hydroxysteroid dehydrogenases [3]. The concept therefore includes both construction of the sterol scaffold from isoprenoid metabolism and its enzymatic diversification, but excludes ribosomally encoded peptide synthesis and non-isoprenoid pathways yielding structurally unrelated cyclic lipids.
  • 4
  • 23 Sep 2026
Topic Review
Combinatorial Biosynthesis
Combinatorial biosynthesis is a strategy in metabolic engineering and synthetic biology that involves the systematic reassembly, modification, or recombination of biosynthetic genes, enzymes, or gene clusters to generate novel or variant metabolic pathways and, consequently, structurally modified natural product derivatives [1]. The approach exploits the modular architecture of biosynthetic enzyme systems—most notably polyketide synthases (PKSs) and nonribosomal peptide synthetases (NRPSs)—to create chemical diversity by swapping, deleting, or rearranging functional domains, altering substrate specificity, or combining biosynthetic elements from distinct native pathways [2]. Many biosynthetic pathways are organized into modular gene clusters encoding assembly-line-like megasynthases, whose domain architecture can be rationally or semi-randomly reconfigured to produce libraries of structurally diversified compounds [3]. Combinatorial biosynthesis is distinguished from precursor-directed biosynthesis, which relies on feeding modified precursors to wild-type organisms, and from directed evolution, which introduces random mutations into existing genes; instead, it operates at the level of pathway reassembly and domain swapping using defined genetic elements [4].
  • 3
  • 23 Sep 2026
Topic Review
Non-Ribosomal Peptide Biosynthesis
Non-ribosomal peptide biosynthesis is an enzyme-directed pathway by which microorganisms, particularly bacteria and fungi, assemble peptide natural products independently of ribosomal translation, messenger RNA templates, and transfer RNA-mediated decoding. It is principally mediated by non-ribosomal peptide synthetases (NRPSs): large, modular, multidomain enzymes in which successive modules determine the ordered incorporation of amino acid or other carboxylate-derived building blocks into a growing product [1][2]. A canonical elongation module contains an adenylation domain that selects and activates a substrate, a thiolation/peptidyl-carrier-protein domain that covalently tethers the activated intermediate through a 4′-phosphopantetheinyl arm, and a condensation domain that forms the peptide bond with the upstream intermediate [1][3]. Optional catalytic domains can alter tethered residues, including by epimerization or heterocyclization, while terminal release domains commonly liberate the product through hydrolysis, cyclization, or related reactions [2][3]. The pathway is distinguished from ribosomal peptide biosynthesis by its assembly-line enzymology and its capacity to incorporate diverse non-proteinogenic substrates rather than being limited by the genetically encoded translation system [1][2].
  • 3
  • 23 Sep 2026
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