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Topic Review
Computational Approaches to Enzyme Inhibition by Natural Products
The exploration of biologically relevant chemical space for the discovery of small bioactive molecules present in marine organisms has led not only to important advances in certain therapeutic areas, but also to a better understanding of many life processes. The still largely untapped reservoir of countless metabolites that play biological roles in marine invertebrates and microorganisms opens new avenues and poses new challenges for research. Computational technologies provide the means to (i) organize chemical and biological information in easily searchable and hyperlinked databases and knowledgebases; (ii) carry out cheminformatic analyses on natural products; (iii) mine microbial genomes for known and cryptic biosynthetic pathways; (iv) explore global networks that connect active compounds to their targets (often including enzymes); (v) solve structures of ligands, targets, and their respective complexes using X-ray crystallography and NMR techniques, thus enabling virtual screening and structure-based drug design; and (vi) build molecular models to simulate ligand binding and understand mechanisms of action in atomic detail.
  • 1.3K
  • 23 Feb 2023
Topic Review
PR Proteins with Enzymatic Action in Plant Defense
Plant defense depends on constitutive and induced factors combined as defense mechanisms. These mechanisms involve a complex signaling network linking structural and biochemical defense. Antimicrobial and pathogenesis-related (PR) proteins are examples of this mechanism, which can accumulate extra- and intracellular space after infection. 
  • 1.3K
  • 14 Sep 2023
Topic Review
Cholic Acid
Matrix metalloproteinase-9 (MMP-9) plays a crucial role in cell invasion and cancer metastasis. In this study, we showed that cholic acid (CA), a major primary bile acid, can induce MMP-9 expression in colon cancer HT29 and SW620 cells. CA increased reactive oxygen species (ROS) production and also activated phosphorylation of ERK1/2, JNK, and p38 MAPK. Specific inhibitors and mutagenesis studies showed that ERK1/2 and JNK functioned as upstream signals in the activation of AP-1, and p38 MAPK functioned as an upstream signal in the activation of NF-κB. N-acetyl-L-cysteine (NAC, an ROS scavenger) and diphenyleneiodonium chloride (DPI, an NADPH oxidase inhibitor) inhibited CA-induced activation of ERK1/2, JNK, and p38 MAPK, indicating that ROS production by NADPH oxidase could be the furthest upstream signal in MMP-9 expression. Colon cancer cells pretreated with CA showed remarkably enhanced invasiveness. Such enhancement was partially abrogated by MMP-9-neutralizing antibodies. These results demonstrate that CA could induce MMP-9 expression via ROS-dependent ERK1/2, JNK-activated AP-1, and p38-MAPK-activated NF-κB signaling pathways, which in turn stimulate cell invasion in human colon cancer cells.
  • 1.3K
  • 30 Oct 2020
Topic Review
VitD and Autoimmune Thyroid Disease
Vitamin D is a steroid hormone traditionally connected to phosphocalcium metabolism. The discovery of pleiotropic expression of its receptor and of the enzymes involved in its metabolism have led to exploration of the other roles of this vitamin, namely on autoimmune thyroid disease. Most of the existing data support a relationship between vitamin D deficiency and a greater tendency for development and/or higher titers of antibodies linked to Hashimoto's thyroiditis, Graves' disease, and/or postpartum thyroiditis. The nature of this relationship is yet unknown, it may be due to vitamin D's immunoregulatory role, emerge as a consequence of the autoimmune disease, or be a result physiopathological process underlying the autoimmune disease. Our thesis is that, due to its immunoregulatory role, vitamin D plays a minor role in conjunction with myriad other factors. In some cases, a vicious cycle is generated, thus contributing to the deficiency and aggravating the autoimmune process.
  • 1.3K
  • 21 Sep 2020
Topic Review
Bloom Syndrome
Bloom syndrome is an inherited disorder characterized by short stature, a skin rash that develops after exposure to the sun, and a greatly increased risk of cancer.
  • 1.3K
  • 24 Dec 2020
Topic Review
Multidrug Resistance
Multidrug resistance (MDR) transporters belonging to either the ATP-Binding Cassette (ABC) or Major Facilitator Superfamily (MFS) groups are major determinants of clinical drug resistance in fungi. The overproduction of these proteins enables the extrusion of incoming drugs at rates that prevent lethal effects. The promiscuity of these proteins is intriguing because they export a wide range of structurally unrelated molecules. Research in the last two decades has used multiple approaches to dissect the molecular basis of the polyspecificity of multidrug transporters. With large numbers of drug transporters potentially involved in clinical drug resistance in pathogenic yeasts, this review focuses on the drug transporters of the important pathogen Candida albicans. This organism harbors many such proteins, several of which have been shown to actively export antifungal drugs. Of these, the ABC protein CaCdr1 and the MFS protein CaMdr1 are the two most prominent and have thus been subjected to intense site-directed mutagenesis and suppressor genetics-based analysis. Numerous results point to a common theme underlying the strategy of promiscuity adopted by both CaCdr1 and CaMdr1. 
  • 1.3K
  • 03 Feb 2021
Topic Review
Fish Waste as Resource
Following the growth of the global population and the subsequent rapid increase in urbanization and industrialization, the fisheries and aquaculture production has seen a massive increase driven mainly by the development of fishing technologies. Accordingly, a remarkable increase in the amount of fish waste has been produced around the world; it has been estimated that about two-thirds of the total amount of fish is discarded as waste, creating huge economic and environmental concerns.
  • 1.3K
  • 28 Sep 2021
Topic Review
PI3K
The phosphoinositide 3-kinase (PI3K) is a family of kinases that play a key role in the biology of chronic lymphocytic leukemia (CLL).
  • 1.3K
  • 19 Mar 2021
Topic Review
Forest Machine Hybridization
Global climate change is currently taking place, and the change is associated with strong weather fluctuations, which result in calamities, whether of biotic or abiotic origin. During these calamities, there is a glut of wood in the market, and thus its price falls. The falling price requires a reduction in the costs associated with its harvesting. Deployment of hybrid machines can present a solution for this issue and hybrid machines have lower fuel consumption, which contributes to the total costs by up to 82% . The solution correlates with the global trend of reducing emission limits for working machines. The Stage V emission standard is currently valid in the EU.Hybrid drives of forest machines (harvester, forwarder, and skidder) are based on solutions that come from the automotive industry. From the sector of machine hybridization, Sellgren mentioned so-called “engine downsizing”, when engine sizes are scaled down and emissions are thus reduced. The most common hybrid drive design currently utilizes electricity with an aim to solve the issue of a lack of the required power of a smaller engine, for example in harvesters. Such hybridization is referred to in the literature as the electro-hybrid drive.
  • 1.3K
  • 01 Jun 2021
Topic Review
Stable Isotope Fractionation in Diseases
The natural abundance of heavy stable isotopes (13C, 15N, 18O, etc.) is now of considerable importance in many research fields, including human physiology. In fact, it varies between tissues and metabolites due to isotope effects in biological processes, that is, isotope discriminations between heavy and light isotopic forms during enzyme or transporter activity.
  • 1.3K
  • 23 Jun 2021
Topic Review
RNA-Based Nano-Theranostic Approaches for Cancer Management
In the fight against cancer, early diagnosis is critical for effective treatment. Traditional cancer diagnostic technologies, on the other hand, have limitations that make early detection difficult. Therefore, multi-functionalized nanoparticles (NPs) and nano-biosensors have revolutionized the era of cancer diagnosis and treatment for targeted action via attaching specified and biocompatible ligands to target the tissues, which are highly over-expressed in certain types of cancers. Advancements in multi-functionalized NPs can be achieved via modifying molecular genetics to develop personalized and targeted treatments based on RNA interference. Modification in RNA therapies utilized small RNA subunits in the form of small interfering RNAs (siRNA) for overexpressing the specific genes of, most commonly, breast, colon, gastric, cervical, and hepatocellular cancer.
  • 1.3K
  • 15 Dec 2021
Topic Review
Oral and Periodontal Bacteria Microbiota Photobiomodulation
The visible and near-infrared wavelengths can affect bacterial growth. Like in eukaryotic cells also in bacteria, photobiomodulation can affect cellular metabolism, homeostasis, defence to stress, and life-and-death mechanisms. Light-bacteria interaction for microbiota management can represent a supportive medical approach in health and illness patients.
  • 1.3K
  • 11 Feb 2022
Topic Review
Poly-L-Lactic Acid as a Biomaterial
Synthetic biopolymers are effective cues to replace damaged tissue in the tissue engineering (TE) field, both for in vitro and in vivo application. Among them, poly-l-lactic acid (PLLA) has been highlighted as a biomaterial with tunable mechanical properties and biodegradability that allows for the fabrication of porous scaffolds with different micro/nanostructures via various approaches. Tissue engineering applications of biomaterials have widely focused on studying synthetic polymers due to their interesting mechanical strength, elasticity, and biodegradability.
  • 1.3K
  • 01 Apr 2022
Topic Review
COVID-19 Fake News in Brazilian Portuguese Language
Public health interventions to counter the COVID-19 pandemic have accelerated and increased digital adoption and use of the Internet for sourcing health information. Unfortunately, there is evidence to suggest that it has also accelerated and increased the spread of false information relating to COVID-19. The consequences of misinformation, disinformation and misinterpretation of health information can interfere with attempts to curb the virus, delay or result in failure to seek or continue legitimate medical treatment and adherence to vaccination, as well as interfere with sound public health policy and attempts to disseminate public health messages. While there is a significant body of literature, datasets and tools to support countermeasures against the spread of false information online in resource-rich languages such as English and Chinese, there are few such resources to support Portuguese, and Brazilian Portuguese specifically.
  • 1.3K
  • 29 Apr 2022
Topic Review
Thermoregulatory Mechanisms in Altricial and Precocial Species
Thermoregulation in newborn mammals is an essential species-specific mechanism of the nervous system that contributes to their survival during the first hours and days of their life. When exposed to cold weather, which is a risk factor associated with mortality in neonates, pathways such as the hypothalamic–pituitary–adrenal axis (HPA) are activated to achieve temperature control, increasing the circulating levels of catecholamine and cortisol. Consequently, alterations in blood circulation and mechanisms to produce or to retain heat (e.g., vasoconstriction, piloerection, shivering, brown adipocyte tissue activation, and huddling) begin to prevent hypothermia. Determined mainly by physiological maturity, mammals can be classified into altricial and precocial species. Although altricial and precocial newborns have several mechanisms to maintain a stable body temperature, a sudden drop in temperature experienced at birth reduces vigor and affects their feeding ability. Consequently, the acquisition of immunoglobulins and the ingestion of nutrients that fuel thermogenesis are compromised.
  • 1.3K
  • 07 Jul 2022
Topic Review
Hormonal and Neuronal Regulation of Sugar Intake
Carbohydrates are important macronutrients in human and rodent diet patterns that play a key role in crucial metabolic pathways and provide the necessary energy for proper body functioning. Sugar homeostasis and intake require complex hormonal and nervous control to proper body energy balance. Added sugar in processed food results in metabolic, cardiovascular, and nervous disorders. The homeostasis of blood glucose or fructose levels requires strong interaction of not only the endocrine system (pancreatic hormones, stress hormones) but also communication of the nervous system. 
  • 1.3K
  • 04 Aug 2022
Topic Review
Food Waste and Circular Economy
The world’s population is expected to grow at an increasing rate, leading to increased food consumption and waste production. Even though food waste represents one of the most challenging economic and environmental issues of the 21st century, it also provides a vast array of valuable resources. Eight broad themes emerged in circular economy: (1) anaerobic digestion of food waste for circular economy creation; (2) food waste systems and life cycle assessments for circular economy; (3) bio-based circular economy approaches; (4) consumer behavior and attitudes toward circular economies; (5) food supply chains and food waste in a circular economy; (6) material flow analysis and sustainability; (7) challenges, policies, and practices to achieve circularity; and (8) circular economy and patterns of consumption. 
  • 1.3K
  • 25 Aug 2022
Topic Review
Regulation of cGAS Activity and Downstream Signaling
Cyclic GMP-AMP synthase (cGAS) is a predominant and ubiquitously expressed cytosolic dsDNA sensor that activates innate immune responses by producing a second messenger, cyclic GMP-AMP (cGAMP), and activating the stimulator of interferon genes (STING). cGAS contains a highly disordered N-terminus, which can sense genomic/chromatin DNA, while the C terminal of cGAS binds dsDNA liberated from various sources, including mitochondria, pathogens, and dead cells. Furthermore, cGAS cellular localization dictates its response to foreign versus self-DNA.
  • 1.3K
  • 23 Sep 2022
Topic Review
Acquisition Initiation (ISPL)
Acquisition Initiation is the initial process within the Information Services Procurement Library (ISPL) and is executed by a customer organization intending to procure Information Services. The process is composed of two main activities: the making of the acquisition goal definition and the making of the acquisition planning. During the acquisition initiation, an iterative process arises in which questions about the goal of the acquisition are usually asked. In response to these questions the Library provides details of the requirements, covering areas such as cost, feasibility and timelines. An example of such requirements is the "planning of the acquisition", a component that may also lead to more questions about the acquisition goal (thus, it is reasonable to state that a relationship exists between the acquisition goal and the acquisition planning). The process-data model shown in the following section displays the acquisition initiation stages. It shows both the process and the data ensuing from the process, and parts of the image will also be used as references in the body of this article. The concepts and data found in the model are explained in separate tables which can be found in the section immediately following the model. A textual, and more thorough, explanation of the activities and concepts that make up the Acquisition Initiation process can be found in the remainder of this article.
  • 1.3K
  • 30 Sep 2022
Topic Review
Hydrogel Spacer SpaceOAR Vue for Prostate Radiotherapy
Damage in the surrounding structures, including the rectum, due to unintended exposure to radiation is a large burden to bear for patients who undergo radiation therapy for prostate cancer. The use of injectable rectal spacers to distance the anterior rectum from the prostate is a potential strategy to reduce the dose of unintended radiation to the rectum. Hydrogel spacers are gaining increasing popularity in the treatment regimen for prostate cancer. After FDA approval of SpaceOAR, specialists are receiving an increasing number of referrals for hydrogel placements. 
  • 1.3K
  • 03 Nov 2022
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