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Topic Review
Electric Organ
In biology, the electric organ is an organ common to all electric fish used for the purposes of creating an electric field. The electric organ is derived from modified nerve or muscle tissue. The electric discharge from this organ is used for navigation, communication, mating, defense and also sometimes for the incapacitation of prey.
  • 3.4K
  • 29 Sep 2022
Topic Review
Anti-Fungal Efficacy of Flavonoids
The prevalence of fungal infections is growing at an alarming pace and the pathogenesis is still not clearly understood. Recurrence of these fungal diseases is often due to their evolutionary avoidance of antifungal resistance. The development of suitable novel antimicrobial agents for fungal diseases continues to be a major problem in the current clinical field. Hence, it is urgently necessary to develop surrogate agents that are more effective than conventional available drugs. Among the remarkable innovations from earlier investigations on natural-drugs, flavonoids are a group of plant-derived substances capable of promoting many valuable effects on humans. The identification of flavonoids with possible antifungal effects at small concentrations or in synergistic combinations could help to overcome this problem. A combination of flavonoids with available drugs is an excellent approach to reduce the side effects and toxicity.
  • 3.4K
  • 10 Jun 2021
Topic Review
Grazing
Grazing is a method of feeding in which a herbivore feeds on plants such as grasses, or other multicellular organisms such as algae. In agriculture, grazing is one method used whereby domestic livestock are used to convert grass and other forage into meat, milk and other products. Many small selective herbivores follow larger grazers, who skim off the highest, tough growth of plants, exposing tender shoots. For terrestrial animals, grazing is normally distinguished from browsing in that grazing is eating grass or forbs, and browsing is eating woody twigs and leaves from trees and shrubs. Grazing differs from true predation because the organism being grazed upon is not generally killed. Grazing differs from parasitism as the two organisms live together in a constant state of physical externality (i.e. low intimacy). Water animals that feed for example on algae found on stones are called grazers-scrapers. Grazers-scrapers feed also on microorganisms and dead organic matter on various substrates.
  • 3.3K
  • 16 Nov 2022
Topic Review
Application of Natural Coagulants in Water Treatment
The most popular and conventional method for water treatment (WT)  is the use of chemical-based coagulants including ferric chloride (FeCl3), alum (AlCl3), synthetic polymers (polyacrylamide), and poly aluminum. However, the use of this approach is not sustainable as it leads to the production of a large volume of non-biodegradable sludge. Natural coagulants, on the other hand, serve as an alternative sustainable strategy for the removal of turbidity and WT, as they are cheap, safe, and biodegradable. Natural coagulants are derived from three major sources, which include plants, animals, and microorganisms.
  • 3.2K
  • 02 Dec 2022
Topic Review
Resveratrol and Human Skin Lightening
Resveratrol is a polyphenol compound found in many edible plants such as Vitis vinifera, and its inhibitory effects on the catalytic activity, gene expression, and posttranslational modifications of tyrosinase, a key enzyme in the melanin biosynthetic pathway, provide a mechanistic basis for its antimelanogenic effects seen in melanocytic cells, three-dimensionally reconstituted skin models, and in vivo animal models. Recent clinical studies have supported the efficacy of resveratrol and its analogs, such as resveratryl triacetate (RTA) and resveratryl triglycolate (RTG), in human skin lightening. These findings suggest that resveratrol and its analogs are potentially useful as skin lightening agents in cosmetics.
  • 2.9K
  • 29 Jul 2021
Topic Review
Metabolism and Role of Creatine
Creatine is a key player in  energy metabolism of excitable cells. This is an essential outline of its role and procurement by the organism, adapted by the author (Balestrino M, University of Genoa, Italy) from his Open Access paper  Role of Creatine in the Heart: Health and Disease, that was published in Nutrients, 2021; 13(4):1215. https://doi.org/10.3390/nu13041215.
  • 2.8K
  • 27 Apr 2021
Topic Review
Family in Medieval Society
One of the periods with the greatest social, cultural, and religious changes was, without a doubt, the European medieval period. The concept of “Family” was one of the fields that gradually evolved, from individuals who shared the same biological lineage, to members of the same “House”. One of the ways to study the concept of “Family” in ancient periods is through a bioarchaeological perspective, where both anthropology and genetics have proven to be essential disciplines for studying “Families”. Through burial rituals, observing whether the graves were single or multiple, as is carried out in the study of human remains, it discusses the profound contribution of anthropology to the “Family” investigation, through mobility studies, the investigation of biological sex, observing certain congenital anomalies or, even, the study of certain ancient infectious diseases. Concerning genetics, the study of bones or teeth allows us to determine whether individuals were from the same close family or if they belonged to the same lineage through the maternal and paternal sides, being one of the only scientific ways of proposing social relationships between individuals, such as that created through adoption.
  • 2.8K
  • 28 Feb 2024
Topic Review
Reactive Oxygen Species in Macrophages
Reactive oxygen species (ROS) are a chemically defined group of reactive molecules derived from molecular oxygen. ROS are involved in a plethora of processes in cells in all domains of life, ranging from bacteria, plants and animals, including humans. The importance of ROS for macrophage-mediated immunity is unquestioned. Their functions comprise direct antimicrobial activity against bacteria and parasites as well as redox-regulation of immune signaling and induction of inflammasome activation.
  • 2.8K
  • 10 May 2021
Topic Review
Dextran
Dextran is an exopolysaccharide (EPS) synthesized by lactic acid bacteria (LAB) or their enzymes in the presence of sucrose. Dextran is composed of a linear chain of d-glucoses linked by α-(1→6) bonds, with possible branches of d-glucoses linked by α-(1→4), α-(1→3), or α-(1→2) bonds, which can be low (<40 kDa) or high molecular weight (>40 kDa). The characteristics of dextran in terms of molecular weight and branches depend on the producing strain, so there is a great variety in its properties. Dextran has commercial interest because its solubility, viscosity, and thermal and rheological properties allow it to be used in food, pharmaceutical, and research areas. 
  • 2.8K
  • 07 Jul 2021
Topic Review
Crocodile
Crocodiles (family Crocodylidae) or true crocodiles are large semiaquatic reptiles that live throughout the tropics in Africa, Asia, the Americas and Australia. The term crocodile is sometimes used even more loosely to include all extant members of the order Crocodilia, which includes the alligators and caimans (family Alligatoridae), the gharial and false gharial (family Gavialidae) among other extinct taxa. Although they appear similar, crocodiles, alligators and the gharial belong to separate biological families. The gharial, with its narrow snout, is easier to distinguish, while morphological differences are more difficult to spot in crocodiles and alligators. The most obvious external differences are visible in the head, with crocodiles having narrower and longer heads, with a more V-shaped than a U-shaped snout compared to alligators and caimans. Another obvious trait is that the upper and lower jaws of the crocodiles are the same width, and the teeth in the lower jaw fall along the edge or outside the upper jaw when the mouth is closed; therefore, all teeth are visible, unlike an alligator, which possesses in the upper jaw small depressions into which the lower teeth fit. Also, when the crocodile's mouth is closed, the large fourth tooth in the lower jaw fits into a constriction in the upper jaw. For hard-to-distinguish specimens, the protruding tooth is the most reliable feature to define the species' family. Crocodiles have more webbing on the toes of the hind feet and can better tolerate saltwater due to specialized salt glands for filtering out salt, which are present, but non-functioning, in alligators. Another trait that separates crocodiles from other crocodilians is their much higher levels of aggression. Crocodile size, morphology, behaviour and ecology differ somewhat among species. However, they have many similarities in these areas as well. All crocodiles are semiaquatic and tend to congregate in freshwater habitats such as rivers, lakes, wetlands and sometimes in brackish water and saltwater. They are carnivorous animals, feeding mostly on vertebrates such as fish, reptiles, birds and mammals, and sometimes on invertebrates such as molluscs and crustaceans, depending on species and age. All crocodiles are tropical species that, unlike alligators, are very sensitive to cold. They separated from other crocodilians during the Eocene epoch, about 55 million years ago. Many species are at the risk of extinction, some being classified as critically endangered.
  • 2.8K
  • 21 Oct 2024
Topic Review
Infrared Spectroscopy in Biological Studies
Infrared (IR) radiation is electromagnetic radiation with wavenumbers ranges of 12,500–10 cm−1. The IR region in the electromagnetic spectrum can be subdivided into three spectral regions, namely near-IR (NIR, 12,500–4000 cm−1), mid-IR (MIR, 4,000–400 cm−1), and far-IR (FIR, 400–10 cm−1). Accumulating evidence has shown that IR radiation has been widely investigated for biological studies and effects. The interaction between IR radiation and biomolecules enables to study the specific molecular vibrations of the sample constituents. IR spectroscopy, specifically MIR, has been used to investigate large numbers of biological samples such as cells, tissues, organ, and biofluids, providing qualitative and quantitative information that could be used for detection and classification. Notably, FTIR spectroscopy is considered a promising tool to study and analyze biological samples using MIR radiation. 
  • 2.8K
  • 09 Jan 2023
Topic Review
Runx2 and Osteoblasts
Runx2 is essential for osteoblast differentiation, chondrocyte maturation, and transdifferentiation of terminally differentiated chondrocytes into osteoblasts. During osteoblast differentiation, Runx2 is weakly expressed in uncommitted mesenchymal cells, and its expression is upregulated in preosteoblasts, reaches the maximal level in immature osteoblasts, and is down-regulated in mature osteoblasts. Runx2 enhances the proliferation of osteoblast progenitors by directly regulating Fgfr2 and Fgfr3. Runx2 enhances the proliferation of suture mesenchymal cells and induces their commitment into osteoblast lineage cells through the direct regulation of hedgehog (Ihh, Gli1, and Ptch1), Fgf (Fgfr2 and Fgfr3), Wnt (Tcf7, Wnt10b, and Wnt1), and Pthlh (Pthr1) signaling pathway genes, and Dlx5. Runx2 heterozygous mutation causes open fontanelle and sutures because more than half of the Runx2 gene dosage is required for the induction of these genes in suture mesenchymal cells. Runx2 induces the proliferation of osteoblast progenitors and their differentiation into osteoblasts through reciprocal regulation via major signaling pathways, including Fgf, hedgehog, Wnt, and Pthlh, and transcription factors, including Sp7 and Dlx5. Runx2 also regulates the expression of bone matrix protein genes, including Col1a1, Col1a2, Spp1, and Bglap/Bglap2. Bglap/Bglap2 (osteocalcin) aligns biological apatite parallel to the collagen fibrils, which is important for bone strength, but osteocalcin does not play a role as a hormone in the pancreas, testis, and muscle. 
  • 2.7K
  • 22 Apr 2021
Topic Review
Tumor Invasion and Metastasis
Metastasis is considered one of the hallmarks of cancer and enhanced tumor invasion and metastasis is significantly associated with cancer mortality. Metastasis occurs via a series of integrated processes involving tumor cells and the tumor microenvironment. The innate immune components of the microenvironment have been shown to engage with tumor cells and not only regulate their proliferation and survival, but also modulate the surrounding environment to enable cancer progression. 
  • 2.6K
  • 01 Dec 2021
Topic Review
Coenzyme Q10
Coenzyme Q10 (CoQ10) has a number of important roles in the cell that are required for optimal functioning of the immune system. These include its essential role as an electron carrier in the mitochondrial respiratory chain, enabling the process of oxidative phosphorylation to occur with the concomitant production of ATP, together with its role as a potential lipid-soluble antioxidant, protecting the cell against free radical-induced oxidation. Furthermore, CoQ10 has also been reported to have an anti-inflammatory role via its ability to repress inflammatory gene expression. Recently, CoQ10 has also been reported to play an important function within the lysosome, an organelle central to the immune response.
  • 2.6K
  • 27 May 2021
Topic Review
Roof Plate in Neural Development
The roof plate is the most dorsal region of the neural tube. The Roof plate serves as an organizing center that controls proliferation and differentiation of dorsal interneurons. In addition, this region is involved in development of neural crest cells, which are the source of migratory neural crest cells. During early development of the spinal cord, roof plate cells secrete signaling molecules, such as Wnt and BMP family proteins, which regulate development of neural crest cells and dorsal spinal cord. After the dorso-ventral pattern is established, spinal cord dynamically changes its morphology. With this morphological transformation, the lumen of the spinal cord gradually shrinks to form the central canal. Accompanied by formation of the central canal, roof plate cells dramatically stretch along the dorso-ventral axis. During this stretching process, the tips of roof plate cells maintain contact with cells surrounding the shrinking lumen of the spinal cord, eventually exposed to the inner surface of the central canal. In this late stage of the spinal cord development, Wnt secreted by stretched roof plate cells regulates transformation of roof plate cells themselves and promotes proliferation of ependymal cells surrounding the central canal, including neural progenitor cells, in the spinal cord.
  • 2.6K
  • 05 Aug 2021
Topic Review
P-Coumaric Acid in Cosmetics
p-Coumaric acid is a natural metabolite contained in many edible plants, and its antioxidant activities in reducing oxidative stress and inflammatory reactions have been demonstrated in various experimental models. p-Coumaric acid has an optimal structure to be a competitive inhibitor of tyrosinase that catalyzes key reactions in the melanin biosynthetic pathway. Experimental evidence supports this notion as it was found to be a more potent inhibitor of tyrosinase, especially toward human enzymes, than other well-known tyrosinase inhibitors such as arbutin and kojic acid. p-Coumaric acid inhibited melanin synthesis in murine melanoma cells, human epidermal melanocytes, and 3-dimensionally reconstituted human skin models. Ex vivo skin permeation experiments and in vivo efficacy tests for p-coumaric acid confirmed its efficient transdermal delivery and functional efficacy in reducing erythema development and skin pigmentation due to ultraviolet exposure. Human studies further supported its effectiveness in hypopigmentation and depigmentation. These findings suggest that p-coumaric acid has good potential to be used as a skin-lightening active ingredient in cosmetics. 
  • 2.5K
  • 30 Jul 2021
Topic Review
Surface-Functionalized Nanoparticles for Bio-Application
Surface functionalization of nanoparticles applies to the use of covalent and non-covalent bonds—such as hydrogen bonds, electrostatic force, and the van der Waals interactions—to integrate diverse organic and inorganic molecules at the nanoscale. Typically, multiple linker molecules are used to form covalent bonds between ligands and the surfaces of nanoparticles (NPs).
  • 2.5K
  • 20 Apr 2022
Topic Review
Wild Edible Plants in India
Despite significant evidence base on quantifying ecosystem services, the role of biodiversity in supporting such services in diversified landscapes, and how indigenous communities exploit, utilize and manage plant resources in a biocultural regime, remains understudied.  A sum total of 172 WEPs comprising 60 vegetables, 70 fruits, seeds and nuts, 23 underground tubers and 19 mushrooms were collected, consumed, and surplus were marketed by the communities. On average, the number of wild edibles collected annually by households were in the following quantities: 40–240 kg leafy vegetables, 125–386 kg flowers, 120–250 kg fruits, 12–125 kg legumes, 24–120 kg tubers, 5–35 kg mushrooms. Among ethnic groups, the Baiga primitive community utilized 70–90% followed by Gonds (58–81%), Kols (52–78%), Oraons (43–79%), and other communities (38–68%) in different zones. WEPs have contributed to 5–24% (Rs 3559- 12,710) of household income, which was highest in the core zone and lowest in the transition zone. It was observed that WEPs were complemented the diets rather than being a substitute for staple foods. They supplied only 3.7–8.3% of energy and 1.1–4.9% protein requirements; however, they significantly supplemented ascorbic acid, thiamine, calcium, and iron by 38.1–73%, 13.7–35.4%, 17.2–29.1%, 2.6–13.5%, respectively. Significantly higher quantities of nutrients were supplemented in the core zone compared to other zones. WEPs were currently underutilized (less intake) especially in buffer and transition zones, complementing the staple foods and partially supplementing the essential macro- and micro-nutrients. However, these have the potential to fulfill the dietary needs and ensure balanced nutrition, if consumed in recommended portions and sizes.
  • 2.4K
  • 14 Jan 2022
Topic Review
Chloroplasts in Plant Stress Responses
The chloroplast has a central position in oxygenic photosynthesis and primary metabolism. In addition to these functions, the chloroplast has recently emerged as a pivotal regulator of plant responses to abiotic and biotic stress conditions. Chloroplasts have their own independent genomes and gene-expression machinery and synthesize phytohormones and a diverse range of secondary metabolites, a significant portion of which contribute the plant response to adverse conditions.
  • 2.3K
  • 05 Jan 2022
Topic Review
Baddeley's Model of Working Memory
Baddeley's model of working memory is a model of human memory proposed by Alan Baddeley and Graham Hitch in 1974, in an attempt to present a more accurate model of primary memory (often referred to as short-term memory). Working memory splits primary memory into multiple components, rather than considering it to be a single, unified construct. Baddeley & Hitch proposed their three-part working memory model as an alternative to the short-term store in Atkinson & Shiffrin's 'multi-store' memory model (1968). This model is later expanded upon by Baddeley and other co-workers to add a fourth component, and has become the dominant view in the field of working memory. However, alternative models are developing, providing a different perspective on the working memory system. The original model of Baddeley & Hitch was composed of three main components: the central executive which acts as a supervisory system and controls the flow of information from and to its slave systems: the phonological loop and the visuo-spatial sketchpad. The phonological loop stores verbal content, whereas the visuo-spatial sketchpad caters to visuo-spatial data. Both the slave systems only function as short-term storage centers. In 2000, Baddeley added a third slave system to his model, the episodic buffer. Baddeley & Hitch's argument for the distinction of two domain-specific slave systems in the older model was derived from experimental findings with dual-task paradigms. Performance of two simultaneous tasks requiring the use of two separate perceptual domains (i.e. a visual and a verbal task) is nearly as efficient as performance of the tasks individually. In contrast, when a person tries to carry out two tasks simultaneously that use the same perceptual domain, performance is less efficient than when performing the tasks individually. A fourth component of Baddeley's model was added 25 years later to complement the central executive system. The third slave system was designated as episodic buffer. It is considered a limited-capacity system that provides temporary storage of information by conjoining information from the subsidiary systems, and long-term memory, into a single episodic representation.
  • 2.3K
  • 04 Nov 2022
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