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Topic Review
Synthesis of Polypeptides with Activated Amino Acid Monomers
Commonly, three different synthetic pathways are used to prepare peptides in the laboratory: via the polymerization of amino acid N-carboxyanhydrides (NCAs), amino acid N-thiocarboxyanhydrides (NTAs), and N-phenoxycarbonyl amino acids (NPCs); via various stepwise coupling reactions of α-amino acids, such as during solid phase peptide synthesis (SPPS); or via recombinant DNA techniques for expressing peptides in microorganisms. Polypeptides that are synthesized through SPPS have controlled primary sequences and can fulfill certain functionalities, but it is difficult to create high molecular weight polypeptides above 100 residues, due to the inevitable side reactions. Recombinant DNA techniques can create polypeptides with specific sequences and high molecular weights. Moreover, they allow for peptide production on a very large scale. However, specialized equipment, which is not readily available in most synthetic laboratories, is needed for this method. The polymerization of activated amino acid monomers enables the formation of bioactive and high molecular weight polypeptides in a facile and expedient manner. The process begins with the conversion of amino acids into the corresponding activated monomers; afterwards, polymerization is initiated in the presence of certain initiators. Although polypeptides that are synthesized in this way lack precise sequence control, their synthetic advantages make this method attractive and economical for synthesizing polypeptides in large quantities.
  • 1.4K
  • 12 May 2022
Topic Review
Digital Twin Concept Developing on an Electrical System
Through the transformation that the electrical sector has been passing by, improvements in asset management and the guarantee of sustainable and quality services have become essential aspects for power companies. Thus, the digitalization of energy utilities presents itself as an important and crucial process. A concept that involves a variety of innovative trends is the digital twin. It consists of a 3D virtual replica of existing physical objects and real-time monitoring of certain measures. By developing a digital twin in the electrical power grid, a virtual replica of the network is obtained providing network virtual maps, 3D asset models, dynamic and real-time data of grid assets, and IoT sensing. All these data can feed a platform where AI-based models and advanced field operation technologies and solutions will be applied. With a Network Digital Twin©development, applications involving on-field activities can be improved through augmented reality (AR) and virtual reality (VR) to enhance workforce operations. 
  • 1.4K
  • 23 May 2022
Topic Review
Tall Tale
A tall tale is a story with unbelievable elements, related as if it were true and factual. Some tall tales are exaggerations of actual events, for example fish stories ("the fish that got away") such as, "That fish was so big, why I tell ya', it nearly sank the boat when I pulled it in!" Other tall tales are completely fictional tales set in a familiar setting, such as the European countryside, the American frontier, the Canadian Northwest, or the beginning of the Industrial Revolution. Events are often told in a way that makes the narrator seem to have been a part of the story; the tone is generally good-natured. The line between legends and tall tales is distinguished primarily by age; many legends exaggerate the exploits of their heroes, but in tall tales the exaggeration looms large, to the extent of dominating the story.
  • 1.4K
  • 09 Nov 2022
Topic Review
Prescription Costs
Prescription costs are a common health care cost for many people and also the source of economic hardship for some.
  • 1.4K
  • 02 Dec 2022
Topic Review
Targeting Ferroptosis for Ischemia-Reperfusion Injury
Ischemia-reperfusion (I/R) injury is a major challenge in perioperative medicine that contributes to pathological damage in various conditions, including ischemic stroke, myocardial infarction, acute lung injury, liver transplantation, acute kidney injury and hemorrhagic shock. I/R damage is often irreversible, and current treatments for I/R injury are limited. Ferroptosis, a type of regulated cell death characterized by the iron-dependent accumulation of lipid hydroperoxides, has been implicated in multiple diseases, including I/R injury. Emerging evidence suggests that ferroptosis can serve as a therapeutic target to alleviate I/R injury, and pharmacological strategies targeting ferroptosis have been developed in I/R models.
  • 1.4K
  • 09 Dec 2022
Topic Review
Biliary Tract Cancers
Biliary tract carcinomas (BTCs) are a heterogeneous group of malignancies arising from the epithelial lining of the bile ducts or gallbladder.
  • 1.4K
  • 28 Oct 2021
Topic Review
The bHLH Transcription Factor Family in Plants
Plant basic helix-loop-helix (bHLH) transcription factors are involved in many physiological processes, and they play important roles in the abiotic stress responses. bHLH transcription factors are among the superfamilies that are commonly found in plants and animals. The conserved bHLH domain contains approximately 60 amino acids (aa), including a basic DNA binding region and two amphipathic α-helices that are separated by a loop region with a variable length. The basic region consists of the first 15 amino acids. Most bHLH proteins have a glutamic acid residue at position 9 (E9), which can interact with the CA nucleotides in the DNA sequence.
  • 1.4K
  • 02 Feb 2023
Topic Review
Properties and Acne Treatment of Tea Tree Oil
Tea tree oil is an essential oil extracted from Melaleuca alternifolia (Maiden & Betch) Cheel with known antibacterial, anti-inflammatory, and antioxidant properties and widely used in cosmetic products to treat acne vulgaris. 
  • 1.4K
  • 06 Jul 2023
Topic Review
Age-Related Alterations at Neuromuscular Junction
With advancing aging, a decline in physical abilities occurs, leading to reduced mobility and loss of independence. Although many factors contribute to the physio-pathological effects of aging, an important event seems to be related to the compromised integrity of the neuromuscular system, which connects the brain and skeletal muscles via motoneurons and the neuromuscular junctions (NMJs). NMJs undergo severe functional, morphological, and molecular alterations during aging and ultimately degenerate. The effect of this decline is an inexorable decrease in skeletal muscle mass and strength, a condition generally known as sarcopenia. Moreover, several studies have highlighted how the age-related alteration of reactive oxygen species (ROS) homeostasis can contribute to changes in the neuromuscular junction morphology and stability, leading to the reduction in fiber number and innervation. Increasing evidence supports the involvement of epigenetic modifications in age-dependent alterations of the NMJ. In particular, DNA methylation, histone modifications, and miRNA-dependent gene expression represent the major epigenetic mechanisms that play a crucial role in NMJ remodeling. It is established that environmental and lifestyle factors, such as physical exercise and nutrition that are susceptible to change during aging, can modulate epigenetic phenomena and attenuate the age-related NMJs changes.
  • 1.4K
  • 15 Jun 2021
Topic Review
LIN28-let-7-ARID3B Pathway
Placental disorders are a major cause of pregnancy loss in humans, and 40%–60% of embryos are lost between fertilization and birth. Successful embryo implantation and placental development requires rapid proliferation, invasion, and migration of trophoblast cells. In recent years, microRNAs (miRNAs) have emerged as key regulators of molecular pathways involved in trophoblast function. A miRNA binds its target mRNA in the 3ʹ-untranslated region (3ʹ-UTR), causing its degradation or translational repression. Lethal-7 (let-7) miRNAs induce cell differentiation and reduce cell proliferation by targeting proliferation-associated genes. The oncoprotein LIN28 represses the biogenesis of mature let-7 miRNAs. Proliferating cells have high LIN28 and low let-7 miRNAs, whereas differentiating cells have low LIN28 and high let-7 miRNAs. In placenta, low LIN28 and high let-7 miRNAs can lead to reduced proliferation of trophoblast cells, resulting in abnormal placental development. In trophoblast cells, let-7 miRNAs reduce the expression of proliferation factors either directly by binding their mRNA in 3ʹ-UTR or indirectly by targeting the -rich interaction domain (ARID)3B complex, a transcription-activating complex comprised of ARID3A, ARID3B, and histone demethylase 4C (KDM4C). In this review, we discuss regulation of trophoblast function by miRNAs, focusing on the role of LIN28-let-7-ARID3B pathway in placental development.
  • 1.4K
  • 27 Oct 2020
Topic Review
Gyrate Atrophy
Gyrate atrophy of the choroid and retina, which is often shortened to gyrate atrophy, is an inherited disorder characterized by progressive vision loss. People with this disorder have an ongoing loss of cells (atrophy) in the retina, which is the specialized light-sensitive tissue that lines the back of the eye, and in a nearby tissue layer called the choroid. During childhood, they begin experiencing nearsightedness (myopia), difficulty seeing in low light (night blindness), and loss of side (peripheral) vision. Over time, their field of vision continues to narrow, resulting in tunnel vision. Many people with gyrate atrophy also develop clouding of the lens of the eyes (cataracts). These progressive vision changes lead to blindness by about the age of 50.
  • 1.4K
  • 04 Jan 2021
Topic Review
Circadian Rhythms and Glioblastomas
Gliomas are solid tumors of the central nervous system (CNS) that originated from different glial cells. The World Health Organization (WHO) classifies these tumors into four groups (I–IV) with increasing malignancy. Glioblastoma (GBM) is the most common and aggressive type of brain tumor classified as grade IV. GBMs are resistant to conventional therapies with poor prognosis after diagnosis even when the Stupp protocol that combines surgery and radiochemotherapy is applied. Nowadays, few novel therapeutic strategies have been used to improve GBM treatment, looking for higher efficiency and lower side effects, but with relatively modest results. The circadian timing system temporally organizes the physiology and behavior of most organisms and daily regulates several cellular processes in organs, tissues, and even in individual cells, including tumor cells.
  • 1.4K
  • 15 Aug 2021
Topic Review
Healthy School Canteen Intervention
Implementing a school-based intervention to promote healthier dietary habits in the school environment among Malaysian adolescents using qualitative methods. This qualitative study was conducted in four secondary schools in Perak and Selangor (two urban and two rural schools) that received the intervention (either training or training and food subsidy). A total of eight focus groups (68 students aged 15 years old) and 16 in-depth interviews were conducted with canteen operators, school convenience shop operators, school teachers and school principals in each school. Thematic analysis was used to analyse the qualitative data to identify suitable themes. Finding several initiatives and changes by the schools’ stakeholders to change to a healthy school canteen programme. The stakeholders also noticed the students’ food preferences that influence healthy food intake in canteens and convenience shops. The food vendors and school administrators also found that subsidising healthy meals might encourage healthy eating. Among barriers to implementing healthy school initiatives were the student’s perception of healthy food and their eating habits, which also affect the food vendors’ profit if they want to implement a healthy canteen. The school-based intervention has the potential to promotes healthier eating among school adolescents. Continuous training and monitoring of canteen operators and convenience shops are needed, including building partnerships and educating the students on healthy eating to cultivate healthy eating habits.
  • 1.4K
  • 19 Nov 2021
Topic Review
Nanotechnology Controling Plant Pathogenic Fungi
Nanoparticles are materials with at least one or more dimensions at the scale of 1–100 nm. This definition has taken several materials to be named nanoparticles into account. Nanoparticles that are natural likewise occur in numerous forms, for example, oceanic salt sprays and volcanic dust.
  • 1.4K
  • 17 Sep 2021
Topic Review
NiO-TiO2 p-n Heterojunction
NiO is a typical p-type semiconductor and it has widely been combined with TiO2 to form the p-n heterojunction due to its suitable energy band structure, high charge carrier concentration, high chemical stability and low cost. Decreasing the size of NiO to nanoclusters helps to improve the electron transfer channels on the surface of TiO2, thus enhance photocatalytic hydrogen production efficiency.
  • 1.4K
  • 19 Apr 2022
Topic Review
Actors and Challenges of Participation(s) in Cultural Heritage
Participation has been an important topic in research across different disciplines, including cultural heritage. The panoply of definitions of participation, whether specific to a discipline or not, makes people acknowledge controversy over the term “participation”. Since 2005, the relevance of participation in cultural heritage has been institutionalized through The Council of Europe Framework Convention on the Value of Cultural Heritage for Society, better known as the Faro Convention. It emphasizes that the significance of cultural heritage lies less in the material aspect than in the meanings and uses people attach to them and the values they represent.
  • 1.4K
  • 21 Apr 2022
Topic Review
miRNAs in HTLV-1 Induced T Cell Leukemia
Human T cell leukemia virus type 1 (HTLV-1) was identified as the first pathogenic human retrovirus and is estimated to infect 5 to 10 million individuals worldwide. Unlike other retroviruses, there is no effective therapy to prevent the onset of the most alarming diseases caused by HTLV-1, and the more severe cases manifest as the malignant phenotype of adult T cell leukemia (ATL). MicroRNA (miRNA) dysfunction is a common feature of leukemogenesis, and it is no different in ATL cases. 
  • 1.4K
  • 23 May 2022
Topic Review
Freezing of Gait
Parkinson Disease (PD) primarily affects older adults. It is the second-most common neurodegenerative disease after Alzheimer’s disease. Freezing of Gait (FoG) is a symptom present in approximately 80% of advanced-stage PD’s patients. FoG episodes alter the continuity of gait, and may be the cause of falls that can lead to injuries and even death. The recent advances in the development of hardware and software systems for the monitoring, stimulus, or rehabilitation of patients with FoG has been of great interest to researchers because detection and minimization of the duration of FoG events is an important factor in improving the quality of life. 
  • 1.4K
  • 13 Sep 2023
Topic Review
Vincent's Disease
Acute necrotizing ulcerative gingivitis (ANUG) is a common, non-contagious infection of the gums with sudden onset. The main features are painful, bleeding gums, and ulceration of inter-dental papillae (the sections of gum between adjacent teeth). This disease, along with necrotizing (ulcerative) periodontitis (NP or NUP) is classified as a necrotizing periodontal disease, one of the seven general types of gum disease caused by inflammation of the gums (periodontitis). The often severe gum pain that characterizes ANUG distinguishes it from the more common chronic periodontitis which is rarely painful. If ANUG is improperly treated or neglected, it may become chronic and/or recurrent. The causative organisms are mostly anaerobic bacteria, particularly Fusobacteriota and spirochete species. Predisposing factors include poor oral hygiene, smoking, poor nutrition, psychological stress, and a weakened immune system. When the attachments of the teeth to the bone are involved, the term NUP is used. Treatment of ANUG is by removal of dead gum tissue and antibiotics (usually metronidazole) in the acute phase, and improving oral hygiene to prevent recurrence. Although the condition has a rapid onset and is debilitating, it usually resolves quickly and does no serious harm. The informal name trench mouth arose during World War I as many soldiers developed the disease, probably because of the poor conditions and extreme psychological stress.
  • 1.4K
  • 30 Nov 2022
Topic Review
Molecular Pathways Involved in the Regulation of BCBM
Brain metastasis is one of the major reasons of death in breast cancer (BC) patients, significantly affecting the quality of life, physical activity, and interdependence on several individuals. The tendency to develop breast cancer brain metastases (BCBMs) differs by the BC subtype, varying from almost half with triple-negative breast cancer (TNBC) (HER2− ER− PR−), one-third with HER2+ (human epidermal growth factor receptor 2-positive, and around one-tenth with luminal subclass (ER+ (estrogen positive) or PR+ (progesterone positive)) breast cancer. 
  • 1.4K
  • 29 Dec 2022
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