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Topic Review
Cytochrome P450
Tryptophan is metabolized along three main metabolic pathways, namely the kynurenine, serotonin and indole pathways. The majority of tryptophan is transformed via the kynurenine pathway, catalyzed by tryptophan-2,3-dioxygenase or indoleamine-2,3-dioxygenase, leading to neuroprotective kynurenic acid or neurotoxic quinolinic acid. Serotonin synthesized by tryptophan hydroxylase, and aromatic L-amino acid decarboxylase enters the metabolic cycle: serotonin → N-acetylserotonin → melatonin → 5-methoxytryptamine→serotonin. Recent studies indicate that serotonin can also be synthesized by cytochrome P450 (CYP), via the CYP2D6-mediated 5-methoxytryptamine O-demethylation, while melatonin is catabolized by CYP1A2, CYP1A1 and CYP1B1 via aromatic 6-hydroxylation and by CYP2C19 and CYP1A2 via O-demethylation. In gut microbes, tryptophan is metabolized to indole and indole derivatives. Some of those metabolites act as activators or inhibitors of the aryl hydrocarbon receptor, thus regulating the expression of CYP1 family enzymes, xenobiotic metabolism and tumorigenesis. The indole formed in this way is further oxidized to indoxyl and indigoid pigments by CYP2A6, CYP2C19 and CYP2E1. The products of gut-microbial tryptophan metabolism can also inhibit the steroid-hormone-synthesizing CYP11A1. In plants, CYP79B2 and CYP79B3 were found to catalyze N-hydroxylation of tryptophan to form indole-3-acetaldoxime while CYP83B1 was reported to form indole-3-acetaldoxime N-oxide in the biosynthetic pathway of indole glucosinolates, considered to be defense compounds and intermediates in the biosynthesis of phytohormones. Thus, cytochrome P450 is engaged in the metabolism of tryptophan and its indole derivatives in humans, animals, plants and microbes, producing biologically active metabolites which exert positive or negative actions on living organisms. Some tryptophan-derived metabolites may influence cytochrome P450 expression, affecting cellular homeostasis and xenobiotic metabolism.
  • 1.7K
  • 10 May 2023
Topic Review
Health Benefits of Bread Fortification
Bread is among the most common foods for the world’s population. Therefore, it can be fortified to eliminate deficiencies of nutrients or be a carrier of other substances with a nutritional or physiological effect, bringing health benefits to its consumers, thus impacting sustainable health.
  • 1.7K
  • 25 Oct 2023
Topic Review
Breguet Deux-Ponts
The Breguet 761/763/765 are a family of 1940s and 1950s French double-deck transport aircraft produced by Breguet Aviation. The aircraft were normally called the Deux-Ponts (Double-Decker) but it was not an official name.
  • 1.7K
  • 11 Oct 2022
Topic Review
Fibrodysplasia ossificans progressiva (FOP)
Fibrodysplasia ossificans progressiva (FOP) is an extremely rare heritable disorder of connective tissues characterized by progressive heterotopic ossification in various skeletal sites.
  • 1.7K
  • 28 Sep 2020
Topic Review
Nucleotide Sugars
Nucleotide sugars have essential roles in every living creature. They are the building blocks of the biosynthesis of carbohydrates and their conjugates and their biological reaction pathways are potential targets of drug development. Information on the chemical and biological reactions supports the development of synthetic and analytic methods required.
  • 1.7K
  • 16 Dec 2020
Topic Review
Eco-Friendly Emergent Structural Adhesives
Using adhesives for connection technology has many benefits. It is cost-efficient, fast, and allows homogeneous stress distribution between the bonded surfaces. 
  • 1.7K
  • 22 Apr 2021
Topic Review
Garlic (Allium sativum L.)
Garlic (Allium sativum L.) is one of the most important food products in the world and an ancient and widespread medicinal herb. It is rich in minerals and vitamins, which are both essential nutrients for human health.
  • 1.7K
  • 07 Jul 2021
Topic Review
MNT
MNT (MAX’s Next Tango) is a crucial modulator of MYC, controls several cellular functions, and is activated in most human cancers. It is the largest, most divergent, and most ubiquitously expressed protein of the MXD family. MNT was first described as a MYC antagonist and tumor suppressor. Indeed, 10% of human tumors present deletions of one MNT allele. However, some reports show that MNT functions in cooperation with MYC by maintaining cell proliferation, promoting tumor cell survival, and supporting MYC-driven tumorigenesis in cellular and animal models. Although MAX was originally considered MNT’s obligate partner, it is also known that heterodmerize with MLX. Recent findings demonstrate that MNT can also work independently, as MNT forms homodimers and interacts with proteins both outside and inside of the proximal MYC network, as REL. These complexes are involved in a wide array of cellular processes, from transcriptional repression via SIN3 to the modulation of metabolism through MLX as well as immunity and apoptosis via REL.
  • 1.7K
  • 02 Oct 2021
Topic Review
The Recent Progress on Silver Nanoparticles
Nanomaterials are highly effective,  environmentally friendly, and applicable for various applications. Recently, silver nanoparticles (Ag NPs) are increasingly being synthesized due to their physical, chemical, and biomedical properties. Silver nanoparticles can be synthesized using physical, chemical, and biological methods. Ag NPs are widely applied in electronic and sensing applications.
  • 1.7K
  • 20 Nov 2021
Topic Review
Antibacterial Agents for Concrete
Concrete is the most used material for the construction of millions of structures around the world. Cementitious structures are often exposed to high humidity environments and the attack of atmospheric agents, such as acid rain, which make them vulnerable to microbial attachment with consequent colonization and deterioration over time. In the light of these considerations, the researchers turned their attention to designing green and sustainable alternative materials that exhibit similar characteristics to the traditional concrete by using nanotechnologies.
  • 1.7K
  • 10 Jan 2022
Topic Review
Overall Features of Transdermal Drug Delivery
Transdermal Drug Delivery System (TDDS) is an alternative approach that allows the drug to permeate through skin and enter the systemic circulation, minimizing or avoiding the limitations of oral and parenteral formulations.
  • 1.7K
  • 24 Jun 2022
Topic Review
Ultrasonic Microbubble Cavitation in Tumor Therapy
Chemotherapy has an essential role not only in advanced solid tumor therapy intervention but also in society’s health at large. Chemoresistance, however, seriously restricts the efficiency and sensitivity of chemotherapeutic agents, representing a significant threat to patients’ quality of life and life expectancy. How to reverse chemoresistance, improve efficacy sensitization response, and reduce adverse side effects need to be tackled urgently. Consequently, studies on the effect of ultrasonic microbubble cavitation on enhanced permeability and retention (EPR) have attracted the attention of researchers. Compared with the traditional targeted drug delivery regimen, the microbubble cavitation effect, which can be used to enhance the EPR effect, has the advantages of less trauma, low cost, and good sensitization effect, and has significant application prospects.
  • 1.7K
  • 15 Aug 2022
Topic Review
Structural/Phylogenetic Analysis of SARS-CoV-2 Spike Glycoprotein Variants
The SARS-CoV-2 pandemic, reported for the first time at the end of 2019 in the city of Wuhan (China), has spread worldwide in three years; it lead to the infection of more than 500 million people and about six million dead. SARS-CoV-2 has proved to be very dangerous for human health. Therefore, several efforts have been made in studying this virus. In a short time, about one year, the mechanisms of SARS-CoV-2 infection and duplication and its physiological effect on human have been pointed out. Moreover, different vaccines against it have been developed and commercialized. Since the beginning of the pandemic, SARS-CoV-2 has evolved; it has done so by accumulating mutations in the genome, generating new virus versions showing different characteristics, and which have replaced the pre-existing variants. In general, it has been observed that the new variants show an increased infectivity and cause milder symptoms. The latest isolated Omicron variants contain more than 50 mutations in the whole genome and show an infectivity 10-folds higher compared to the wild-type strain. 
  • 1.7K
  • 05 Sep 2022
Topic Review
Sod Roof
A sod roof, or turf roof, is a traditional Scandinavian type of green roof covered with sod on top of several layers of birch bark on gently sloping wooden roof boards. Until the late 19th century, it was the most common roof on rural log houses in Norway and large parts of the rest of Scandinavia. Its distribution roughly corresponds to the distribution of the log building technique in the vernacular architecture of Finland and the Scandinavian peninsula. The load of approximately 250 kg per m² of a sod roof is an advantage because it helps to compress the logs and make the walls more draught-proof. In winter the total load may well increase to 400 or 500 kg per m² because of snow. Sod is also a reasonably efficient insulator in a cold climate. The birch bark underneath ensures that the roof will be waterproof. The term ‘sod roof’ is somewhat misleading, as the active, water-tight element of the roof is birch bark. The main purpose of the sod is to hold the birch bark in place. The roof might just as well have been called a "birch bark roof", but its grassy outward appearance is the reason for its name in Scandinavian languages: Norwegian and Swedish torvtak, Icelandic torfþak. A sod roof is well suited to the dynamics of a barter economy because the materials are ubiquitous and cost nothing, although the work is labour-intensive. However, a typical household in the era that sod roofs were most common would usually possess a lot of manpower, and neighbours would typically be invited to take part in the roofing party, similar to a barn raising in the United States . The Norwegian term dugnad denotes an established custom in rural communities, where large undertakings were accomplished with help from neighbours.
  • 1.7K
  • 29 Sep 2022
Topic Review
Intergenerationality Programs For Portuguese Population
The aging process is characterized by diverse and complex changes in the individual’s various dimensions, requiring continuous adaptation. In this sense, this transition can be faced from an active aging standpoint through strategies such as intergenerationality programs/projects, resulting in an active social participation and valorization that is so important to life in society. Portugal has undergone demographic changes, significantly transforming its age structure and populational dimension. In 2021, the aging index was 182.1%.
  • 1.7K
  • 02 Dec 2022
Topic Review
Long Non-Coding RNAs in Triple-Negative Breast Cancer
Triple-negative breast cancer (TNBC) is a more aggressive type of breast cancer due to its heterogeneity and complex molecular mechanisms. TNBC has a high risk for metastasis, and it is difficult to manage clinical conditions of the patients. Long non-coding RNAs (lncRNAs) have emerged as a novel target to treat the multistep process of TNBC. LncRNAs regulate epigenetic expression levels, cell proliferation and apoptosis, and tumour invasiveness and metastasis. Thus, lncRNA-based early diagnosis and treatment options could be helpful, especially for patients with severe TNBC. 
  • 1.7K
  • 20 Apr 2023
Topic Review
Diatom-Based Biosensors
Porous materials showing some useful transducing features, i.e., any changes in their physical or chemical properties as a consequence of molecular interaction, are very attractive in the realization of sensors and biosensors. Diatom frustules have been gaining support for biosensors since they are made of nanostructured amorphous silica, but do not require any nano-fabrication step; their surface can be easily functionalized and customized for specific application; diatom frustules are photoluminescent, and they can be found in almost every pond of water on the Earth, thus assuring large and low-cost availability.
  • 1.7K
  • 31 Mar 2021
Topic Review
Kriyananda
Kriyananda (born James Donald Walters; May 19, 1926, Azuga – April 21, 2013, Assisi) was a direct disciple of the yogi Paramahansa Yogananda, and the founder of the Ananda, a worldwide movement of spiritual intentional communities based on Yogananda's World Brotherhood Colonies ideal. Yogananda made Walters a minister for his organization, Self-Realization Fellowship (SRF). He authorized him to teach Kriya Yoga while with SRF, and appointed him the head monk for the SRF Mount Washington monks only. After Yogananda's death, Walters was given final vows of sannyas in 1955 by then SRF President Daya Mata and given the name Kriyananda. In 1960, upon the passing of M.W. Lewis, the SRF Board of Directors elected Kriyananda to the Board of Directors and to the position of Vice President. In 1962, the SRF Board of Directors voted unanimously to request his resignation. Kriyananda is the author of about 150 published books/booklets and the composer of over 400 pieces of music, which altogether have sold over three million copies. A few of the books have been published in 28 languages and a few are sold in 90 countries. He lectured in different countries throughout the world. In addition to English, he spoke Italian, Romanian, Greek, French, Spanish, German, Hindi, Bengali, and Indonesian. He established a new Swami order in 2009: the Nayaswami Order. A jury in a court of law found Kriyananda aka Donald Walters guilty of fraudulently representing himself as a celibate religious leader or swami even though he had sex with several of his devotees during 30 years at the helm of Ananda. Several women came forward during the civil trial to testify that Walters had sexually exploited them.
  • 1.7K
  • 15 Nov 2022
Topic Review
Skin Health
In women, aging and declining estrogen levels are associated with several cutaneous changes, many of which can be reversed or improved by estrogen supplementation. Two estrogen receptors-α and β-have been cloned and found in various tissue types. Epidermal thinning, declining dermal collagen content, diminished skin moisture, decreased laxity, and impaired wound healing have been reported in postmenopausal women. Experimental and clinical studies in postmenopausal conditions indicate that estrogen deprivation is associated with dryness, atrophy, fine wrinkling, and poor wound healing. The isoflavone genistein binds to estrogen receptor β and has been reported to improve skin changes. This review article will focus on the effects of genistein on skin health.
  • 1.7K
  • 03 Nov 2020
Topic Review
Satellite DNA
Repetitive DNA is a major organizational component of eukaryotic genomes, being intrinsically related with their architecture and evolution. Tandemly repeated satellite DNAs (satDNAs) can be found clustered in specific heterochromatin-rich chromosomal regions, building vital structures like functional centromeres and also dispersed within euchromatin. Interestingly, despite their association to critical chromosomal structures, satDNAs are widely variable among species due to their high turnover rates. This dynamic behavior has been associated with genome plasticity and chromosome rearrangements, leading to the reshaping of genomes.
  • 1.7K
  • 19 Jul 2021
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