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Topic Review
BRCA Mutation
A BRCA mutation is a mutation in either of the BRCA1 and BRCA2 genes, which are tumour suppressor genes. Hundreds of different types of mutations in these genes have been identified, some of which have been determined to be harmful, while others have no proven impact. Harmful mutations in these genes may produce a hereditary breast–ovarian cancer syndrome in affected persons. Only 5–10% of breast cancer cases in women are attributed to BRCA1 and BRCA2 mutations (with BRCA1 mutations being slightly more common than BRCA2 mutations), but the impact on women with the gene mutation is more profound. Women with harmful mutations in either BRCA1 or BRCA2 have a risk of breast cancer that is about five times the normal risk, and a risk of ovarian cancer that is about ten to thirty times normal. The risk of breast and ovarian cancer is higher for women with a high-risk BRCA1 mutation than with a BRCA2 mutation. Having a high-risk mutation does not guarantee that the woman will develop any type of cancer, or imply that any cancer that appears was actually caused by the mutation, rather than some other factor. High-risk mutations, which disable an important error-free DNA repair process (homology directed repair), significantly increase the person's risk of developing breast cancer, ovarian cancer and certain other cancers. Why BRCA1 and BRCA2 mutations lead preferentially to cancers of the breast and ovary is not known, but lack of BRCA1 function seems to lead to non-functional X-chromosome inactivation. Not all mutations are high-risk; some appear to be harmless variations. The cancer risk associated with any given mutation varies significantly and depends on the exact type and location of the mutation and possibly other individual factors. Mutations can be inherited from either parent and may be passed on to both sons and daughters. Each child of a genetic carrier, regardless of sex, has a 50% chance of inheriting the mutated gene from the parent who carries the mutation. As a result, half of the people with BRCA gene mutations are male, who would then pass the mutation on to 50% of their offspring, male or female. The risk of BRCA-related breast cancers for men with the mutation is higher than for other men, but still low. However, BRCA mutations can increase the risk of other cancers, such as colon cancer, pancreatic cancer, and prostate cancer. Methods to diagnose the likelihood of a patient with mutations in BRCA1 and BRCA2 getting cancer were covered by patents owned or controlled by Myriad Genetics. Myriad's business model of exclusively offering the diagnostic test led to Myriad growing from being a startup in 1994 to being a publicly traded company with 1200 employees and about $500M in annual revenue in 2012; it also led to controversy over high prices and the inability to get second opinions from other diagnostic labs, which in turn led to the landmark Association for Molecular Pathology v. Myriad Genetics lawsuit.
  • 1.8K
  • 01 Dec 2022
Topic Review
Ischemia and Reperfusion
Ischemia and reperfusion (I/R) causes a reduction in arterial blood supply to tissues, followed by the restoration of perfusion and consequent reoxygenation. The reestablishment of blood flow triggers further damage to the ischemic tissue through reactive oxygen species (ROS) accumulation, interference with cellular ion homeostasis, and inflammatory responses to cell death. In normal conditions, ROS mediate important beneficial responses. When their production is prolonged or elevated, harmful events are observed with peculiar cellular changes. In particular, during I/R, ROS stimulate tissue inflammation and induce NLRP3 inflammasome activation. The mechanisms underlying the activation of NLRP3 are several and not completely elucidated. It was recently shown that NLRP3 might sense directly the presence of ROS produced by normal or malfunctioning mitochondria or indirectly by other activators of NLRP3. Aim of the present review is to describe the current knowledge on the role of NLRP3 in some organs (brain, heart, kidney, and testis) after I/R injury, with particular regard to the role played by ROS in its activation. Furthermore, as no specific therapy for the prevention or treatment of the high mortality and morbidity associated with I/R is available, the state of the art of the development of novel therapeutic approaches is illustrated.
  • 1.8K
  • 03 Nov 2020
Topic Review
Financial Derivatives
This book, Financial Derivatives, a blessing or a curse? (DerivaQuote, 2006), introduces financial derivatives, their uses and the debates surrounding their use. It looks at whether one should fear them or embrace them by digging into literature, theory and case studies.  The world seems to be divided into two camps: those who embrace financial derivatives as the ‘Holy Grail’ of the new investment area, and those who denigrate derivatives as the financial Antichrist (Edington, 1994). As the quote above suggests, there are many conflicting views and opinions on derivatives and their use. Derivatives are seen either as useful instruments or as a complete waste of time and money. Experience has indicated that derivative products have transformed the way firms view financial risk and mitigate it. It is no longer relatively simple, and risks are changing continuously with innovation. Risks are no longer nationwide but global and the internet and other fast communication channels have further complicated the issue. In the article, ‘Are Derivatives Financial "Weapons of Mass Destruction"?’ Simon (2008) explains that although derivative instruments have been used to hedge risks that were previously left open, there are still those who are sceptical about using these instruments. As the Group of Thirty (G30) (1993) note, users from “both inside and outside of the financial industry, remain uncomfortable with derivatives activity.” Moreover, the latest survey by the Bank for International Settlements (2009) suggests that there is widespread employment of derivatives with adequate risk management systems. Nevertheless, not all firms are immune to derivatives misuse. This book uses literature and case studies to determine whether it is misuse of this financial instrument, and not the derivatives instrument itself, that causes firm failure and large losses. These case studies help to pinpoint the root causes of these incidents.
  • 1.8K
  • 28 Oct 2020
Topic Review
Neutrophils
Neutrophils are the most abundant circulating and first-responding innate myeloid cells and have so far been underestimated in the context of multiple sclerosis (MS). MS is the most frequent, immune-mediated, inflammatory disease of the central nervous system. MS is treatable but not curable and its cause(s) and pathogenesis remain elusive. The involvement of neutrophils in MS pathogenesis has been suggested by the use of preclinical animal disease models, as well as on the basis of patient sample analysis. In this review, we provide an overview of the possible mechanisms and functions by which neutrophils may contribute to the development and pathology of MS. Neutrophils display a broad variety of e ector functions enabling disease pathogenesis, including (1) the release of inflammatory mediators and enzymes, such as interleukin-1 , myeloperoxidase and various proteinases, (2) destruction and phagocytosis of myelin (as debris), (3) release of neutrophil extracellular traps, (4) production of reactive oxygen species, (5) breakdown of the blood–brain barrier and (6) generation and presentation of autoantigens. An important question relates to the issue of whether neutrophils exhibit a predominantly proinflammatory function or are also implicated in the resolution of chronic inflammatory responses in MS.
  • 1.8K
  • 05 Sep 2025
Topic Review
Gemcitabine Resistance in PDAC
Gemcitabine remains the standard of care for all stages of PDAC, however, with poor clinical benefits which is considered to be due to reduced drug availability in tumor cells. Gemcitabine-induced cytotoxicity depends upon sufficient drug uptake followed by intracellular activation. 
  • 1.8K
  • 24 Dec 2020
Topic Review
Melittin
Melittin, a 26-amino acid peptide, is the main component of the venom of four honeybee species and exhibits neuroprotective actions. Melittin alleviates HT22 in vivo and in vitro oxidative stress injury induced by Aβ25–35; For the first time, melittin has been reported to enhance cognitive function in a learning memory-deficit model; Melittin ameliorating mechanisms were observed via the nuclear translocation of Nrf2, stimulating 1-HO production and the regulation of the TrkB/CREB/BDNF pathway.
  • 1.8K
  • 23 Nov 2021
Topic Review
Arginine Metabolism and Cancer
Arginine availability and activation of arginine-related pathways at cancer sites have profound effects on the tumor microenvironment, far beyond their well-known role in the hepatic urea cycle. Arginine metabolism impacts not only malignant cells but also the surrounding immune cells behavior, modulating growth, survival, and immunosurveillance mechanisms, either through an arginase-mediated effect on polyamines and proline synthesis, or by the arginine/nitric oxide pathway in tumor cells, antitumor T-cells, myeloid-derived suppressor cells, and macrophages. 
  • 1.8K
  • 24 Dec 2021
Topic Review
Detrimental Effects of School Corporal Punishment on Children
School corporal punishment (SCP) is still a widely used and legal practice in many countries for disciplining children. The infliction of SCP upon children is associated with externalizing behavior problems, internalizing behavior problems, and reduced school performance. Awareness of its detrimental effects is needed to make the school environment a safe place for all children across the world.
  • 1.8K
  • 18 Mar 2022
Topic Review
Antibodies in HIV-infection and HIV-vaccine development
The structure of HIV-envelope changes as the infection progresses and is one of the biggest obstacles in developing of HIV-vaccine. HIV-infection can cause the production of various natural autoantibodies, including catalytic antibodies hydrolyzing DNA, myelin basic protein, histones, HIV-integrase, HIV-reverse transcriptase, β-casein, serum albumin, and some other natural substrates. Currently, there are various directions for the development of HIV vaccines: stimulation of the immune response on the mucous membranes; induction of cytotoxic T cells, which lyse infected cells and hold back HIV-infection; immunization with recombinant Env proteins or vectors encoding Env; mRNA-based vaccines and some others. 
  • 1.8K
  • 22 Mar 2022
Topic Review
Overview of Colicins and Microcins
The family Enterobacteriaceae is a large, heterogeneous group of Gram-negative bacteria, which includes strains that naturally inhabit the gastrointestinal tract (GIT) of animals and humans. Being considered normal commensal members of the GIT microbiota, these microbes can also live and multiply in food environments. Additionally, Enterobacteriaceae are acknowledged as indicators of food production hygiene, preservation, and storage, often being used as indicators of food quality and safety. Additionally, Salmonella spp., Yersinia enterocolitica, pathogenic Escherichia coli, including Escherichia coli O157:H7, and Shigella spp., among others, are important foodborne pathogens. Moreover, some members of this group, namely Citrobacter, Enterobacter, Erwinia, Klebsiella, Kluyvera, Pantoea, and Serratia, have been described both as harboring plant growth-promoting characteristics and attaining pathogenicity potential.
  • 1.8K
  • 17 Oct 2022
Topic Review
Poliomyelitis Eradication
Poliomyelitis eradication refers to a permanent elimination of all cases of poliomyelitis (polio) infection around the world. A public health effort to this end began in 1988, led by the World Health Organization (WHO), the United Nations Children's Fund (UNICEF) and the Rotary Foundation. These organizations, along with the U.S. Centers for Disease Control and Prevention (CDC) and The Gates Foundation, have spearheaded the campaign through the Global Polio Eradication Initiative (GPEI), which helps to coordinate vaccination campaigns, environmental monitoring, evaluation of possible polio cases and logistics. Successful eradication of infectious diseases has been achieved twice before, with smallpox and rinderpest. Prevention of disease spread is accomplished by vaccination. There are two kinds of polio vaccine—oral polio vaccine (OPV), which uses weakened poliovirus, and inactivated polio vaccine (IPV), which is injected. The OPV is less expensive and easier to administer, and can spread immunity beyond the person vaccinated, creating contact immunity. It has been the predominant vaccine used. However, under conditions of long-term vaccine virus circulation in under-vaccinated populations, mutations can reactivate the virus to produce a polio-inducing strain, while the OPV can also, in rare circumstances, induce polio or persistent asymptomatic infection in vaccinated individuals, particularly those that are immunodeficient. Being inactivated, the IPV is free of these risks but does not induce contact immunity. IPV is more costly and the logistics of delivery are more challenging. The 22 diagnosed wild polio virus (WPV) cases worldwide in 2017[needs update] represented a 97% reduction from the 719 diagnosed cases in 2000 and a 99.99% reduction from the estimated 350,000 cases when the eradication effort began in 1988. Of the three strains of polio virus, the last recorded wild case caused by type 2 (WPV2) was in 1999, and WPV2 was declared eradicated in 2015. Type 3 (WPV3) is last known to have caused polio on 11 November 2012, with all wild-virus cases since that date being due to type 1 (WPV1). All three types are represented among the periodic cases arising from mutated oral vaccine strains, so-called circulating vaccine-derived poliovirus (cVDPV). India is the latest country to have officially stopped endemic transmission of polio, with its last reported case in 2011. Three countries remain where the disease is endemic—Afghanistan, Pakistan and Nigeria.
  • 1.8K
  • 20 Oct 2022
Topic Review
Hyperpolarization
Hyperpolarization is the nuclear spin polarization of a material in a magnetic field far beyond thermal equilibrium conditions determined by the Boltzmann distribution. It can be applied to gases such as 129Xe and 3He, and small molecules where the polarization levels can be enhanced by a factor of 104-105 above thermal equilibrium levels. Hyperpolarized noble gases are typically used in magnetic resonance imaging (MRI) of the lungs. Hyperpolarized small molecules are typically used for in vivo metabolic imaging. For example, a hyperpolarized metabolite can be injected into animals or patients and the metabolic conversion can be tracked in real-time. Other applications include determining the function of the neutron spin-structures by scattering polarized electrons from a very polarized target (3He), surface interaction studies, and neutron polarizing experiments.
  • 1.8K
  • 03 Nov 2022
Topic Review
Configuration Space
In classical mechanics, the parameters that define the configuration of a system are called generalized coordinates, and the space defined by these coordinates is called the configuration space of the physical system. It is often the case that these parameters satisfy mathematical constraints, such that the set of actual configurations of the system is a manifold in the space of generalized coordinates. This manifold is called the configuration manifold of the system. Notice that this is a notion of "unrestricted" configuration space, i.e. in which different point particles may occupy the same position. In mathematics, in particular in topology, a notion of "restricted" configuration space is mostly used, in which the diagonals, representing "colliding" particles, are removed.
  • 1.8K
  • 25 Nov 2022
Topic Review
Dietary Macronutrients That Prompt MetS via Mitochondria
Metabolic syndrome (MetS) is a cluster of metabolic risk factors for diabetes, coronary heart disease, non-alcoholic fatty liver disease, and some tumors. It includes insulin resistance, visceral adiposity, hypertension, and dyslipidemia. MetS is primarily linked to lipotoxicity, with ectopic fat deposition from fat storage exhaustion, more than obesity per se. Excessive intake of long-chain saturated fatty acid and sugar closely relates to lipotoxicity and MetS through several pathways, including toll-like receptor 4 activation, peroxisome proliferator-activated receptor-gamma regulation (PPARγ), sphingolipids remodeling, and protein kinase C activation. These mechanisms prompt mitochondrial dysfunction, which plays a key role in disrupting the metabolism of fatty acids and proteins and in developing insulin resistance. 
  • 1.8K
  • 21 Mar 2023
Topic Review Peer Reviewed
Academic Freedom in US Higher Education: Rights Emergent from the Law and the Profession
The various definitions of academic freedom in the United States reflect the influence of social and political norms in its interpretation as both a professional and legal right. Yet, underlying these interpretations is the operational understanding, which includes both legal and professional considerations, that academic freedom is a widely recognized principle that grants professors the autonomy and authority to explore intellectual questions within their academic disciplines, conduct professional work, and express their views in the public sphere without undue interference or suppression. In other words, academic freedom is a foundational principle rooted in legal and institutional frameworks that safeguards professors’ ability to engage in intellectual inquiry, professional practice, and public discourse without undue interference. This principle extends beyond mere professional courtesy. It is recognized as essential to the functioning of higher education institutions and the broader democratic exchange of ideas. The public (including policymakers, industry leaders, media, and students) generally acknowledges academic freedom as an inherent protection that protects from unjustified interferences. By doing so, professors can participate in governance, disciplinary leadership, and extramural activities without the fear of retaliation or coercion. By insulating academic work from ideological, political, or economic constraints, academic freedom maintains the legitimacy and independence of scholarly inquiry in service to both knowledge advancement and the public good.
  • 1.8K
  • 20 May 2025
Topic Review
Soil Biology in the Ecuadorian Amazon
For many decades the Ecuadorian Amazon has been used as source of resources for cities both at national and international level. These facts had important consequences and environmental impacts, affecting from the smallest living organisms of the soil to the indigenous communities and peoples that inhabit the Amazon rainforest, as well as the flora and fauna biodiversity. With the change in land use, the Amazonian territory has been progressively affected and it is gradually decreasing, leaving behind poor soils.  Production conditions result modified by the implementation of large monocultures and livestock systems, a situation that directly affects soil and soil fauna. For this reason, we considered interesting to study, understand and compare the behavior of building organisms in natural and intervened areas, through sampling, inventories and laboratory analysis with the aim of developing and implementing production systems (chakras, agroforestry or silvopastoral systems), which benefit both the small producer and the ecosystem and life that inhabits it. Since there are no easily available compiled papers regarding the "Soil Biology in the Ecuadorian Amazon" in this work we collect information that allows us to offer a framework on the topics of changes in land use, typology of Amazonian soils and its main inhabitats organisms. All these date let to be considered as evidences of the degree of the health/disturbance of the corresponding soils.
  • 1.8K
  • 28 Oct 2020
Topic Review
Glycosylation
Post-translational modifications are one way that biomineral-associated cells control the function and fate of proteins. Of the ten different types of post-translational modifications, one of the most interesting and complex is glycosylation, or the covalent attachment of carbohydrates to amino acid sidechains Asn, Ser, and Thr of proteins. There are several biomineral-associated glycoproteins that have been characterized, and a subset of these have been the subject of intensive in vitro experimentation.  These studies indicate that glycosylation does not alter the inherent function of the biomineralization protein; rather, it either accentuates or attenuates protein functionality. In essence, glycosylation gives the cell the “last word” as to what degree a biomineralization protein will participate in the biomineralization process.
  • 1.8K
  • 25 Sep 2020
Topic Review
Deadly Helminthiasis
Helminthiasis is an expensive management problem in sheep and goat industry, because the gastrointestinal parasites develop resistance against all anthelmintic chemical products which are discovered and produced by the pharmaceutical industry. The use of natural tannin containing forages such as Sericea Lespedeza is highly promising. Helminthiasis is the invasion of internal parasites into the GI tract of domestic animals, even in humans, causing serious deadly consequences. Sheep and goats are more seriously afflicted than other farm animals. Helminthiasis results in high mortality rate, and poor growth rates, low reproductive performances and low quality products produced from infected animals, which increase high production costs. Anthelmintic drug has been used as the most common control method against gastrointestinal nematodes (GIN) infection. Overuse and misuse of these drugs caused significant GIN resistance against the drugs, especially in sheep and goat production.  
  • 1.8K
  • 18 Jan 2021
Topic Review
Metal-Free Carbon-Based Supercapacitors-A Comprehensive Review
This state-of-the-art entry aims to highlight  advances in metal-free carbon-based supercapacitors over the last 20 years. Author discuss the various types of carbons (without metals) used (activated, nanoforms of carbon, and doped carbons) as well as key parameters in supercapacitor performance such as surface area, porosity, and functional groups.
  • 1.8K
  • 18 Jan 2021
Topic Review
Annin Rich Extracts Traditional Applications
Tannins are polyphenolic compounds historically utilized in textile and adhesive industries, but also in traditional human and animal medicines or foodstuffs.
  • 1.8K
  • 04 Feb 2021
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