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Topic Review
Antioxidant Compounds Extracted from Plants for Vegetable Oils
Oil oxidation is the main factor limiting vegetable oils’ quality during storage, as it leads to the deterioration of oil’s nutritional quality and gives rise to disagreeable flavors. These changes make fat-containing foods less acceptable to consumers. To deal with this problem and to meet consumer demand for natural foods, vegetable oil fabricators and the food industry are looking for alternatives to synthetic antioxidants to protect oils from oxidation. In this context, natural antioxidant compounds extracted from different parts (leaves, roots, flowers, and seeds) of medicinal and aromatic plants (MAPs) could be used as a promising and sustainable solution to protect consumers’ health. 
  • 2.0K
  • 21 Nov 2022
Topic Review
Calcium Indicator NCaMP7
Green fluorescent genetically encoded calcium indicators (GECIs) are the most popular tool for visualization of calcium dynamics in vivo. However, most of them are based on the EGFP protein and have similar molecular brightnesses. The NTnC indicator, which is composed of the mNeonGreen fluorescent protein with the insertion of troponin C, has higher brightness as compared to EGFP-based GECIs, but shows a limited inverted response with an ΔF/F of 1. By insertion of a calmodulin/M13-peptide pair into the mNeonGreen protein, we developed a green GECI called NCaMP7. In vitro, NCaMP7 showed positive response with an ΔF/F of 27 and high affinity (Kd of 125 nM) to calcium ions. NCaMP7 demonstrated a 1.7-fold higher brightness and similar calcium-association/dissociation dynamics compared to the standard GCaMP6s GECI in vitro. According to fluorescence recovery after photobleaching (FRAP) experiments, the NCaMP7 design partially prevented interactions of NCaMP7 with the intracellular environment. The NCaMP7 crystal structure was obtained at 1.75Å resolution to uncover the molecular basis of its calcium ions sensitivity.The NCaMP7 indicator retained a high and fast response when expressed in cultured HeLa and neuronal cells. Finally, we successfully utilized the NCaMP7 indicator for in vivo visualization of grating-evoked and place-dependent neuronal activity in the visual cortex and the hippocampus of mice using a two-photon microscope and an NVista miniscope, respectively.
  • 2.0K
  • 26 Oct 2020
Topic Review
COP9 Signalosome
The COP9 signalosome (CSN) is a regulator of the ubiquitin proteasome system (UPS). In mammalian cells it occurs as an eight-subunit protein complex, six Proteasome-COP9 signalosome-Initiation factor eIF3 (PCI)-domain subunits including CSN1-4, CSN7 and CSN8 and two MOV34-Pad1-N-terminal (MPN)-domain subunits called CSN5 and CSN6. The CSN regulates cullin-RING-ubiquitin ligases (CRLs) by specifically removing NEDD8 from cullins. In cooperation with CAND1 it controls the adaptation of the CRL network to fluctuations in substrate availability. The CSN complex belongs to the JAMM family of deubiquitylating enzymes (DUBs). In addition, it interacts with other deubiquitylating enzymes including USP15 and USP48 coordinating ubiquitylation and deubiquitylation activities.
  • 2.0K
  • 26 Oct 2020
Topic Review
Machine Learning and Artificial Intelligence
Machine learning (ML) is a type of artificial intelligence (AI) consisting of algorithmic approaches that enable machines to solve problems deprived of explicit computer programming. 
  • 2.0K
  • 28 Apr 2023
Topic Review
Extracellular Vesicle
Extracellular vesicles (EVs) are constituted by a group of heterogeneous membrane vesicles secreted by most cell types that play a crucial role in cell–cell communication.
  • 2.0K
  • 25 Mar 2021
Topic Review
Coronal Shear Fractures of the Distal Humerus
Coronal shear fractures are partial or complete articular fractures of the distal humerus without involvement of the columns, which can affect the capitellum, the trochlea, or both.
  • 2.0K
  • 11 Jan 2022
Topic Review
HIV Infection within the CNS
HIV can traverse the BBB using a Trojan horse-like mechanism. Hidden within infected immune cells, HIV can infiltrate the highly safeguarded CNS and propagate disease. Once integrated within the host genome, HIV becomes a stable provirus, which can remain dormant, evade detection by the immune system or antiretroviral therapy (ART), and result in rebound viraemia. As ART targets actively replicating HIV, has low BBB penetrance, and exposes patients to long-term toxicity, further investigation into novel therapeutic approaches is required.
  • 2.0K
  • 13 Jul 2022
Topic Review
Landtag
A Landtag (State Diet) is a representative assembly (parliament) in German-speaking countries with legislative authority and competence over a federated state (Land). Landtage assemblies are the legislative bodies for the individual states of Germany and states of Austria, and have authority to legislate in non-federal matters for the regional area. Likewise, the Landtag of South Tyrol (Italian: Consiglio della Provincia autonoma di Bolzano) is the legislature of the autonomous province of South Tyrol in northeast Italy. In the sovereign principality of Liechtenstein the national parliament is called the Landtag of Liechtenstein.
  • 2.0K
  • 04 Nov 2022
Topic Review
Antifragile
Antifragile: Things That Gain From Disorder is a book by Nassim Nicholas Taleb published on November 27, 2012, by Random House in the United States and Penguin in the United Kingdom. This book builds upon ideas from his previous works including Fooled by Randomness (2001), The Black Swan (2007–2010), and The Bed of Procrustes (2010–2016) and is the fourth book in the five-volume philosophical treatise on uncertainty titled Incerto. Some of the ideas are expanded in Taleb’s fifth book Skin in the Game: Hidden Asymmetries in Daily Life (2018).
  • 2.0K
  • 30 Nov 2022
Topic Review
Prebiotic Synthesis of Ribose
Prebiotic reactions describe how biomolecules such as ribose, was synthesized and protected from degradation, nucleobases generated from HCN oligomers and other derivatives including prebiotic RNA (preRNA) were formed at the given circumstances. Prebiotic conditions remained a subject of debate, but a reasonable aspect to consider is that tetrahedral structure shaping biomolecules consisted almost exclusively of elements belonging to the CHNOPS group in the periodic table, where capital letters correspond to the elements of carbon, hydrogen, nitrogen, oxygen, phosphorus and sulfur. Intermediary steps in the formose reaction network contain aldol condensation, aldose-ketose isomerizations, producing C3 - C6 carbohydrates including pentoses. The generation of genetic material could have developed from the formose reaction to ribose and further to non-genetic prebiotic  RNA (preRNA) [1-9]. Consecutive reactions of this pathway are not known. Those known abiotic chemical reactions were selected that could have resulted in preRNA and genetic RNA (genRNA).  Processes generating primitive life on Earth consisted of three successive stages: i) abiotic reactions generating organic molecules, ii) formation of molecular aggregates showing primitive metabolism, iii) development of primitive cells and organisms resembling those that exist today. Only cellular life is known that adapted in every aspect to conditions that exist only on Earth. Here only the 1st stage, the abiotic phase is dealt with. Prebiotic conditions remained subjects of debate ranging from a strong reductive to a strong oxidative climate. Our theory is based on a mildly reductive atmosphere that could have existed at the beginning of life some 4.3 -4.5 billion years ago, much before the Great Oxidation Event that took place much later 2.3 - 2.5 billion years ago. During the abiotic synthesis of organic molecules, ribose was selected as the precursor to life. .
  • 2.0K
  • 15 Jun 2021
Topic Review
Two-Dimensional MoTe2 Hetero-Phase Homojunctions
Two-dimensional (2D) hetero-phase homojunctions comprise a semiconducting phase of a material as the channel and a metallic phase of the material as electrodes. In particular, MoTe2 exhibits intriguing properties and its phase is easily altered from semiconducting 2H to metallic 1T′ and vice versa, owing to the extremely small energy barrier between these two phases. MoTe2 thus finds potential applications in electronics as a representative 2D material with multiple phases. 
  • 2.0K
  • 19 Jan 2022
Topic Review
Lipid-Oligonucleotide Conjugates and the Development of RNA-Based Therapeutics
Antisense and small interfering RNA (siRNA) oligonucleotides have been recognized as powerful therapeutic compounds for targeting mRNAs and inducing their degradation. However, a major obstacle is that unmodified oligonucleotides are not readily taken up into tissues and are susceptible to degradation by nucleases. For these reasons, the design and preparation of modified DNA/RNA derivatives with better stability and an ability to be produced at large scale with enhanced uptake properties is of vital importance.
  • 2.0K
  • 01 Feb 2023
Topic Review
Mid-Upper Arm Circumference to Predict Malnutrition
The double burden of malnutrition (under- and overnutrition) is a serious public health issue in childhood. The mid-upper arm circumference (MUAC) is a simple tool for screening nutritional status, but studies of the optimal cutoff to define malnutrition are limited. This study aimed to explore the prediction of malnutrition by MUAC in Sri Lankan schoolchildren. The participants were 538 students (202 boys, 336 girls) aged 5–10 years. Spearman’s rank correlation was calculated for MUAC and both body-mass-index-for-age z-score (BAZ) and height-for-age z-score (HAZ). Receiver operating characteristic (ROC) analysis was conducted to assess the ability of MUAC to correctly classify malnutrition, after stratifying for age and birth weight. MUAC correlated significantly with BAZ (r = 0.84) and HAZ (r = 0.35). The areas under the ROC curve for thinness, overweight, obesity, and stunting were 0.88, 0.97, 0.97, and 0.77, respectively. The optimal MUAC cutoff values for predicting thinness and stunting were 167.5 mm and 162.5 mm, respectively; the optimal cutoffs for predicting overweight and obesity were 190.5 mm and 218.0 mm, respectively. These cutoffs differed after stratification by age group and birth weight. Our results confirm MUAC to be a useful tool for monitoring growth in schoolchildren.
  • 2.0K
  • 30 Oct 2020
Topic Review
Antimicrobial Activity of Calixarenes/Related Macrocycles
Calixarenes have been shown to have antimicrobial effects since the 1950s. These properties are exemplified through their applications as prodrugs, drug delivery agents and biofilm inhibitors. A particularly important development in recent years has been their ability to engage in multivalent interactions with proteins, thus inhibiting cellular aggregation.
  • 2.0K
  • 12 Dec 2020
Topic Review
Leucoagaricus gongylophorus and Leaf-Cutting Ants
Leaf-cutting ants are eusocial insects, as they show a highly developed social structure, manifesting ecological relationships. Their complex structure is characterized by an organized social behavior, the cultivation of a fungus garden and high levels of hygiene, which hinders the management of leaf-cutting ants compared to other insects. Leaf-cutting ants cause damage in agricultural and silviculture areas, mainly in monocultures.
  • 2.0K
  • 21 Apr 2022
Topic Review
The Internationalization of Nongovernmental Organizations
Internationalization is one of several growth strategies adopted by both profit and nonprofit organizations. Although the internationalization of business firms has been intensively studied, the internationalization of nongovernmental organizations (NGOs) is still in a growing-up stage as NGOs are focused on serving specific social interests. They may not only be influenced by social, political, and economic goals, but also cater to social or humanitarian services dealing with health, environmental protection, and human rights.
  • 2.0K
  • 02 Nov 2022
Topic Review
Effects of Oat on Blood Pressure
Hypertension (HTN) is a major risk factor for cardiovascular disease (CVD) and cognitive decline. Elevations in blood pressure (BP) leading to HTN can be found in young adults with increased prevalence as people age. Oats can decrease CVD risk via an established effect of β-glucan on the attenuation of blood cholesterol. Oats deliver several beneficial dietary components with putative beneficial effects on BP or endothelial function, such as β-glucan, γ-amino butyric acid (GABA), and phytochemicals such as avenanthramides. 
  • 2.0K
  • 02 Feb 2023
Topic Review
State of the World’s Herbaria
Herbaria remain the primary means of documenting plant life on earth, and the number of herbaria worldwide and the number of specimens they hold continues to grow. Digitization of herbarium specimens, though far from complete, has increased the discoverability of herbarium holdings and has increased the range of studies from which data from herbarium specimens can be used. The rather large number of herbaria about which no current information is available is a source of concern, as is herbarium consolidation and removal of herbaria to offsite storage facilities. Partnerships are key to the future health of herbaria. 
  • 2.0K
  • 09 Jan 2024
Topic Review
Adenosine in inflammation and neoplasia
Adenosine is a purine nucleoside, resulting from the degradation of adenosine triphosphate (ATP). Under adverse conditions, including hypoxia, ischemia, inflammation, or cancer, the extracellular levels of adenosine increase significantly. Once released, adenosine activates cellular signaling pathways through the engagement of the four known G-protein-coupled receptors, adenosine A1 receptor subtype (A1), A2A, A2B, and A3. These receptors, expressed virtually on all immune cells, mitigate all aspects of immune/inflammatory responses. These immunosuppressive effects contribute to blunt the exuberant inflammatory responses, shielding cells, and tissues from an excessive immune response and immune-mediated damage.
  • 2.0K
  • 27 Oct 2020
Topic Review
Fluorescence Microscopy to Aanalyze Lignin
Lignin is one of the most studied and analyzed materials due to its importance in cell structure and in lignocellulosic biomass. Because lignin exhibits autofluorescence, fluorescence microscopy methods have been developed that allow it to be analyzed and characterized directly in plant tissue and in samples of lignocellulose fibers. Compared to destructive and costly analytical techniques, fluorescence microscopy presents suitable alternatives for the analysis of lignin autofluorescence. The existing qualitative methods are Epifluorescence and Confocal Laser Scanning Microscopy; however, other semi-qualitative methods have been developed that allow fluorescence measurements and to quantify the differences in the structural composition of lignin. The methods are fluorescence lifetime spectroscopy, two-photon microscopy, Föster resonance energy transfer, fluorescence recovery after photobleaching, total internal reflection fluorescence, and stimulated emission depletion. With these methods, it is possible to analyze the transport and polymerization of lignin monomers, distribution of lignin of the syringyl or guaiacyl type in the tissues of various plant species, and changes in the degradation of wood by pulping and biopulping treatments as well as identify the purity of cellulose nanofibers through lignocellulosic biomass.
  • 2.0K
  • 21 Mar 2022
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