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Topic Review
Vasculogenic Mimicry in Breast Cancer
In solid tumors, vasculogenic mimicry (VM) is the formation of vascular structures by cancer cells, allowing to generate a channel-network able to transport blood and tumor cells. While angiogenesis is undertaken by endothelial cells, VM is assumed by cancer cells. Besides the participation of VM in tumor neovascularization, the clinical relevance of this process resides in its ability to favor metastasis and to drive resistance to antiangiogenic therapy. VM occurs in many tumor types, including breast cancer, where it has been associated with a more malignant phenotype, such as triple-negative and HER2-positive tumors. The latter may be explained by known drivers of VM, like hypoxia, TGFB, TWIST1, EPHA2, VEGF, matrix metalloproteinases, and other tumor microenvironment-derived factors, which altogether induce the transformation of tumor cells to a mesenchymal phenotype with a high expression rate of stemness markers.
  • 1.3K
  • 29 Mar 2022
Topic Review
A.oligospora Strains in China
Maintaining the effects of nematode-trapping fungi (NTF) agents in order to control plant-parasitic nematodes (PPNs) in different ecological environments has been a major challenge in biological control applications. To achieve such an objective, it is important to understand how populations of the biocontrol agent NTF are geographically and ecologically structured. 
  • 1.3K
  • 26 Oct 2021
Topic Review
Dendrobium Essential Oil
A detailed chemical composition of Dendrobium essential oil has been only reported for a few main species. This article is the first to evaluate the essential oil composition, obtained by steam distillation, of five Indian Dendrobium species: Dendrobium chrysotoxum Lindl., Dendrobium harveyanum Rchb.f., and Dendrobium wardianum R.Warner (section Dendrobium), Dendrobium amabile (Lour.) O’Brien, and Dendrobium chrysanthum Wall. ex Lindl. (section Densiflora). We investigate fresh flower essential oil obtained by steam distillation, by GC/FID and GC/MS. Several compounds are identified, with a peculiar distribution in the species: Saturated hydrocarbons (range 2.19–80.20%), organic acids (range 0.45–46.80%), esters (range 1.03–49.33%), and alcohols (range 0.12–22.81%). Organic acids are detected in higher concentrations in D. chrysantum, D. wardianum, and D. harveyanum (46.80%, 26.89%, and 7.84%, respectively). This class is represented by palmitic acid (13.52%, 5.76, and 7.52%) linoleic acid (D. wardianum 17.54%), and (Z)-11-hexadecenoic acid (D. chrysantum 29.22%). Esters are detected especially in species from section Dendrobium, with ethyl linolenate, methyl linoleate, ethyl oleate, and ethyl palmitate as the most abundant compounds. Alcohols are present in higher concentrations in D. chrysantum (2.4-di-tert-butylphenol, 22.81%), D. chrysotoxum (1-octanol, and 2-phenylethanol, 2.80% and 2.36%), and D. wardianum (2-phenylethanol, 4.65%). Coumarin (95.59%) is the dominant compound in D. amabile (section Densiflora) and detected in lower concentrations (range 0.19–0.54%) in other samples. These volatile compounds may represent a particular feature of these plant species, playing a critical role in interacting with pollinators.
  • 1.3K
  • 22 Sep 2021
Topic Review
Carbon Capture and Storage (CCS)
The carbon capture and storage (CCS) refers to many technologies that capture CO2 at some stage of a combustion process or an industrial process that produces CO2 as waste.
  • 1.3K
  • 03 Nov 2021
Topic Review
Explore Mars by Unmanned Aerial Vehicle
The technology of Unmanned Aerial Vehicles (UAVs) has tremendous potential to support various successful space mission solutions. In general, different techniques for observing space objects are available, such as telescopes, probes, and flying spacecraft, orbiters, landers, and rovers. However, a detailed analysis has been carried out due to the benefits of UAVs relative to other planetary exploration techniques. A prototype UAV has been successfully simulated to fly on Mars’ surface. 
  • 1.3K
  • 24 Jan 2022
Topic Review
Spirocyclic Motifs in Natural Products
Natural products play the central role in drug discovery due to their inherent biological activity and because have a wide span of structural diversity. Spirocyclic compounds have also occupied a special place in medicinal chemistry. Spirocycles are thought to possess a good balance of conformational rigidity and flexibility to be, on one hand, free from absorption and permeability issues characteristic of conformationally more flexible, linear scaffolds. On the other hand, spirocycles are more conformationally flexible compared to, for example, flat aromatic heterocycles and can adapt to many proteins as biological targets; thus, increasing the chances of finding bioactive hits. Spirocycles are distinctly three-dimensional and initial hits can be further optimized via manipulation of the molecular periphery whose three-dimensional positioning is well defined. 
  • 1.3K
  • 25 Apr 2022
Topic Review
Thermal Bridges
Thermal bridges are caused by full or partial penetration of the building envelope by materials with different thermal conductivities, changes in fabric thickness, and/or differences between internal and external areas, such as those found at wall/floor/ceiling junctions).
  • 1.3K
  • 12 May 2022
Topic Review
Conventional Treatment for Wounds
Application of modern delivery techniques to natural bioactive products improves their permeability, bioavailability, and therapeutic efficacy. Many natural products have desirable biological properties applicable to wound healing but are limited by their inability to cross the stratum corneum to access the wound. Over the past two decades, modern systems such as microneedles, lipid-based vesicles, hydrogels, composite dressings, and responsive formulations have been applied to natural products such as curcumin or aloe vera to improve their delivery and efficacy. 
  • 1.3K
  • 30 May 2022
Topic Review
Wavelet Threshold Denoising Algorithm
The denoising performance is affected by several factors, including wavelet basis function, decomposition level, thresholding method, and the threshold selection criteria. Traditional threshold selection rules rely on statistical and empirical variables, which influence their performance in noise reduction under various conditions. 
  • 1.3K
  • 06 Jul 2022
Topic Review
Perl 6
Perl 6 is a member of the Perl family of programming languages. While historically several interpreter and compiler implementations were being written, today only the Rakudo Perl 6 implementation is in active development. It is introducing elements of many modern and historical languages. Compatibility with Perl 5 is not a goal, though a compatibility mode is part of the specification. The design process for Perl 6 began in 2000. In February 2015 a post on The Perl Foundation blog stated that "The Perl6 team will attempt to get a development release of version 1.0 available for Larry's birthday in September and a Version 1.0 release by Christmas", and on 25 December 2015, the first stable version of the specification was announced. Development on Pugs, the first high-traction implementation, began in 2005, and there have been multiple Perl 6 implementation projects. Rakudo Perl 6 is based on NQP (Not Quite Perl) and can use MoarVM or the Java Virtual Machine as a runtime environment, and releases a new version every month (including precompiled GNU/Linux packages); in July 2010, the project released the first Rakudo Star distribution, a collection of a Perl 6 implementation and related materials. Larry Wall maintains a reference grammar known as STD.pm6, written in Perl 6 and bootstrapped with Perl 5.
  • 1.3K
  • 12 Dec 2022
Topic Review
Biogenic Silver Nanoparticles for Their Biomedical Applications
Nanoparticles can be synthesized through physical, chemical, and biological routes, where biologically synthesized nanoparticles are also referred to as biogenic-synthesized nanoparticles or bionanoparticles. Bionanoparticles exploit the inherent reducing property of biological entities to develop cost-effective, non-toxic, time-efficient, sustainable, and stable nanosized particles. There is a wide array biomedical focus on metallic nanoparticles, especially silver nanoparticles, due to their distinctive physiochemical properties making them a suitable therapeutic molecule carrier. This research aims to provide a broad insight into the various classes of living organisms that can be exploited for the development of silver nanoparticles, and elaboratively review the interdisciplinary biomedical applications of biogenically synthesized silver nanoparticles in health and life sciences domains.
  • 1.3K
  • 13 Mar 2023
Topic Review
Flooding Vulnerability in Informal Settlements
Flooding is an increasingly challenging problem facing cities today, with consequences mostly felt in marginalized communities. Residents of informal settlements are particularly susceptible to the effects of flooding given that they are compelled to live in the most unsafe locations, such as floodplains. There is need to mitigate the challenges and strengthen the resiliency of informal settlements in relation to flooding through upgrading housing and infrastructures, green infrastructures, policies, integrating indigenous knowledge, and community participation    
  • 1.3K
  • 02 Apr 2023
Topic Review
M1 Family of Metalloaminopeptidases
Proteolytic enzymes, also known as peptidases, are one of the most abundant groups of enzymes in living organisms. They control the activation, synthesis and turnover of proteins, and regulate most biochemical and physiological processes, such as digestion, fertilization, growth, differentiation, cell signaling/migration, immunological defense, wound healing, and apoptosis. They are consequently major regulators of homeostasis, ageing, and different human diseases like cancer, hypertension, diabetes, inflammation, neurodegeneration, Alzheimer among others. Proteases are also essential for propagation of infectious agents, being major contributors of pathogenesis in several infectious diseases, including the current coronavirus emergent pandemic SARS COVID 19. Among peptidases, aminopeptidases catalyze the cleavage of the N-terminal amino acids of proteins or peptide substrates. They are distributed in many phyla and play critical roles in physiology and pathophysiology. Many of them are metallopeptidases belonging to the M1 and M17 families, among others. Some, such as M1 aminopeptidases N and A, thyrotropin-releasing hormone-degrading ectoenzyme, and M17 leucyl aminopeptidase, are targets for the development of therapeutic agents for human diseases, including cancer, hypertension, central nervous system disorders, inflammation, immune system disorders, skin pathologies, and infectious diseases, such as malaria. 
  • 1.3K
  • 23 May 2023
Topic Review
Bacterial Bioprotectants
Plant growth and nutrition are adversely affected by various factors such as water stress, high temperature, and plant pathogens. Plant-associated microbes play a vital role in the growth and development of their hosts under biotic and abiotic stresses. The use of a rhizosphere microbiome for plant growth stimulation and the biological control of fungal disease can lead to improved crop productivity. Mechanisms used by plant-growth-promoting rhizobacteria (PGPR) to protect plants from soilborne pathogens include antibiosis, the production of lytic enzymes, indole-3 acetic acid production, decreasing ethylene levels by secreting 1-aminocyclopropane-1-carboxylate deaminase, competition for nutrients and niches, parasitism and induced systemic resistance. 
  • 1.3K
  • 09 Jun 2023
Topic Review
Bile Acids, Intestinal Barrier Dysfunction, and Related Diseases
The intestinal barrier is a precisely regulated semi-permeable physiological structure that absorbs nutrients and protects the internal environment from infiltration of pathological molecules and microorganisms. Bile acids are small molecules synthesized from cholesterol in the liver, secreted into the duodenum, and transformed to secondary or tertiary bile acids by the gut microbiota. Bile acids interact with bile acid receptors (BARs) or gut microbiota, which plays a key role in maintaining the homeostasis of the intestinal barrier.
  • 1.3K
  • 25 Aug 2023
Topic Review
Internet of Everything
The Internet of Everything (IoE) represents a paradigm shift in the world of connectivity. While the Internet of Things (IoT) initiated the era of interconnected devices, the IoE takes this concept to new heights by interlinking objects, individuals, data, and processes. Symmetry in IoE innovation and technology is essential for creating a harmonious and efficient ecosystem to ensure that the benefits are accessible to a broad spectrum of society while minimizing potential drawbacks. 
  • 1.3K
  • 14 Nov 2023
Topic Review
Anti-Lipopolysaccharide Factor
Sepsis is a life-threatening complication of an infectious process that results from the excessive and uncontrolled activation of the host’s pro-inflammatory immune response to a pathogen. Lipopolysaccharide (LPS), also known as endotoxin, which is a major component of Gram-negative bacteria’s outer membrane, plays a key role in the development of Gram-negative sepsis and septic shock in humans. To date, no specific and effective drug against sepsis has been developed.
  • 1.3K
  • 22 Nov 2023
Topic Review
Effect of Aggregate on Geopolymer Concrete
The construction industry has become one of the major consumers of renewable and non-renewable natural resources and environment-polluting industries. The development of new green construction materials has become a global need and a driver for recent research trends. The use of geopolymer binders can reduce the consumption of ordinary cement and utilize several wastes that are usually dumped in landfills, causing several environmental issues.
  • 1.3K
  • 08 Jan 2024
Topic Review
Presynaptic Calcium Channels
Presynaptic Ca2+ entry occurs through voltage-gated Ca2+ (CaV) channels which are activated by membrane depolarization. Depolarization accompanies neuronal firing and elevation of Ca2+ triggers neurotransmitter release from synaptic vesicles. For synchronization of efficient neurotransmitter release, synaptic vesicles are targeted by presynaptic Ca2+ channels forming a large signaling complex in the active zone. The presynaptic CaV2 channel gene family (comprising CaV2.1, CaV2.2, and CaV2.3 isoforms) encode the pore-forming α1 subunit. The cytoplasmic regions are responsible for channel modulation by interacting with regulatory proteins.
  • 1.3K
  • 23 Apr 2021
Topic Review
Brain NMDA Receptors
N-methyl-D-aspartate (NMDA) receptor antagonists such as phencyclidine (PCP), dizocilpine (MK-801) and ketamine have long been considered a model of schizophrenia, both in animals and humans. However, ketamine has been recently approved for treatment-resistant depression, although with severe restrictions. Interestingly, the dosage in both conditions is similar, and positive symptoms of schizophrenia appear before antidepressant effects emerge. Here, we describe the temporal mechanisms implicated in schizophrenia-like and antidepressant-like effects of NMDA blockade in rats, and postulate that such effects may indicate that NMDA receptor antagonists induce similar mechanistic effects, and only the basal pre-drug state of the organism delimitates the overall outcome.
  • 1.3K
  • 10 Jun 2021
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