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Topic Review
Minimally Invasive Capsule Panendoscopy
In the early 2000s, the introduction of single-camera wireless capsule endoscopy (CE) redefined small bowel study. Progress continued with the development of double-camera devices, first for the colon and rectum, and then, for panenteric assessment. Advancements continued with magnetic capsule endoscopy (MCE), particularly when assisted by a robotic arm, designed to enhance gastric evaluation.
  • 1.4K
  • 04 Mar 2024
Topic Review
CfDNA Sequencing
Cell free circulating DNA (cfDNA) refers to DNA fragments present outside of cells in body fluids such as plasma, urine, and cerebrospinal fluid (CSF). CfDNA was first identified in 1948 from plasma of healthy individuals. Afterward, studies showed that the quantity of this cfDNA in the blood was increased under pathological conditions such as auto-immune diseases but also cancers.
  • 1.4K
  • 06 Jul 2021
Topic Review
Insulin in the Brain
Insulin action in the brain regulates several processes including energy expenditure, glucose homeostasis, feeding behavior and satiety, reward pathways, reproduction, cell proliferation and differentiation. Moreover, insulin has neuroprotective and neuromodulatory properties and plays a crucial role in neuronal transmission and survival, neurogenesis, plasticity, and memory and cognition.
  • 1.4K
  • 11 Apr 2022
Topic Review
Node
A node is a point along a standing wave where the wave has minimum amplitude. For instance, in a vibrating guitar string, the ends of the string are nodes. By changing the position of the end node through frets, the guitarist changes the effective length of the vibrating string and thereby the note played. The opposite of a node is an anti-node, a point where the amplitude of the standing wave is at maximum. These occur midway between the nodes.
  • 1.4K
  • 16 Nov 2022
Topic Review
Natural Carotenoids
Biotechnologically produced carotenoids occupy an important place in the scientific research. Owing to their role as natural pigments and their high antioxidant properties, microbial carotenoids have been proposed as alternatives to their synthetic counterparts. Natural carotenoids can be obtained either by extraction from plants or via microbial production. To this end, many studies are focusing on their efficient and sustainable production from renewable substrates. Besides the development of an efficient upstream process, their separation and purification as well as their analysis from the microbial biomass confers another important aspect to be adressed.
  • 1.4K
  • 15 May 2023
Topic Review
Cancer Immunotherapy
Cancer treatment has evolved tremendously in the last few decades. Immunotherapy has been considered to be the forth pillar in cancer treatment in addition to conventional surgery, radiotherapy, and chemotherapy. Though immunotherapy has resulted in impressive response, it is generally limited to a small subset of patients. Understanding the mechanisms of resistance toward cancer immunotherapy may shed new light to counter that resistance. In this entry, we highlighted and summarized two major hurdles (recognition and attack) of cancer elimination by the immune system. The mechanisms of failure of some available immunotherapy strategies were also described. Moreover, the significance role of immune compartment for various established cancer treatments were also elucidated . Then, the mechanisms of combinatorial treatment of various conventional cancer treatment with immunotherapy were discussed. Finally, a strategy to improve immune cancer killing by characterizing cancer immune landscape, then devising treatment based on that cancer immune landscape was put forward.
  • 1.4K
  • 21 Oct 2020
Topic Review
Ventilation System
An additional window frame with a ventilation function is applied to the existing window. Thus, when the window is closed, a cavity, which is created between window frames, serves as an air path for ventilation. The additional frame has the same material and finishing as the existing frame, thereby ensuring design consistency. On the outside, the frame does not show any application of the mechanical system. Another advantage of the proposed system is that, as the width is 65 mm, it occupies as small an area as possible and minimally affects the view from the inside. Polyvinyl chloride (PVC), a generally used material for windows, is used for the ventilation system, and this system is formed in a "U"-shape consistent with the existing window frame. This system can be attached or detached on the existing window frame and does not generate either a gap or a distance in the process of installation for airtightness. The cavity is 45 mm in width, 20 mm in depth, and 1940 mm in height and serves as an air path connected to the outdoor air intake and the indoor air supply outlet.
  • 1.4K
  • 26 Oct 2020
Topic Review
NiFe Oxide Electrocatalyst
NiFe electrodes are developed for the oxygen evolution reaction (OER) in an alkaline electrolyser based on an anion exchange membrane (AEM) separator and fed with diluted KOH solution as supporting electrolyte. This study reports on the electrochemical behaviour of two different NiFe-oxide compositions (i.e., Ni1Fe1-oxide and Ni1Fe2-oxide) prepared by the oxalate method. These catalysts are assessed for single-cell operation in an MEA including a Sustainion™ anion-exchange membrane. The electrochemical polarization shows a current density of 650 mA cm−2 at 2 V and 50 °C for the Ni1Fe1 anode composition. A durability test of 500 h is carried out using potential cycling as an accelerated stress-test. This shows a decrease in current density of 150 mA cm−2 mainly during the first 400 h. The performance achieved for the anion-exchange membrane electrolyser single-cell based on the NiFeOx catalyst appears promising. However, further improvements are required to enhance the stability under these operating conditions.
  • 1.4K
  • 30 Dec 2020
Topic Review
Mitophagy and the Brain
Mitophagy is a form of macroautophagy, were mitochondria and their contents are ubiquitinated, engulfed, and removed through lysosome degradation.
  • 1.4K
  • 08 Jan 2021
Topic Review
Safe Nanoparticles
The field of nanotechnology has grown over the last two decades and made the transition from the benchtop to applied technologies. Nanoscale-sized particles, or nanoparticles, have emerged as promising tools with broad applications in drug delivery, diagnostics, cosmetics and several other biological and non-biological areas. These advances lead to questions about nanoparticle safety. Despite considerable efforts to understand the toxicity and safety of these nanoparticles, many of these questions are not yet fully answered. Nevertheless, these efforts have identified several approaches to minimize and prevent nanoparticle toxicity to promote safer nanotechnology.
  • 1.4K
  • 25 Aug 2021
Topic Review
Macrophages and Cancer Development
Macrophages are innate immune cells pivotal for tissue homeostasis, removal of superfluous cells, and inflammatory responses to infections. Macrophages also play diverse roles in cancer development, ranging from antitumor activity in early progression stages to, most commonly, tumor-promoting roles in established cancer. Notably, macrophages are highly plastic cells and, depending on the microenvironmental cues in the Tumor Microenvironment (TME), can undergo marked changes in their function. In established cancers, high macrophage infiltration often strongly associates with poor prognosis or tumor progression in many types of solid tumors, including breast, bladder, head and neck, glioma, melanoma, and prostate cancer. Conversely, in colorectal and gastric cancers, high macrophage infiltration correlates with a better prognosis. These apparently opposite effects are likely related to macrophage plasticity and resultant heterogeneity of phenotype and functions in various cancers.
  • 1.4K
  • 14 May 2021
Topic Review
Parameters Affecting Zeolite T Crystallization
Zeolites are well-known porous crystal systems that exist in various sizes (nano-, micro-, etc.) and have been widely incorporated in different applications. They consist of a uniform size of pore distributions which are also known as voids. Voids and cavities within the zeolite system are the factors that contribute to the unique properties of the zeolite. These voids and cavities are controlled by the type of crystals that grow and intergrowth within the zeolite membrane. Nanoporous zeolite T is identified to have within it an intergrowth framework that makes zeolite type T an exceptional species in the zeolite family.
  • 1.4K
  • 18 Jun 2021
Topic Review
Mitostasis
Mitostasis refers the mitochondrial dynamics of fusion and fission depending on the cell requirements. Mitostasis also involves mitochondrial traficking and anchoring as need to maintain a functional pool of mitochondria.
  • 1.4K
  • 19 Jul 2021
Topic Review
Fluidized Bed Reactors
Fluidized gasification reactors can be used to produce hydrogen. They are operated in three modes including bubbling, circulating, and dual beds, as depicted inC. In a bubbling fluidized bed (BFB), the fuel is introduced from the bottom or side of the bed. The bed starts bubbling when the velocity of gasification agent is beyond the minimum fluidization velocity.
  • 1.4K
  • 18 Sep 2021
Topic Review
Influenza Virus Infections in Cats
In the past, cats were considered resistant to influenza. Today, we know that they are susceptible to some influenza A viruses (IAVs) originating in other species. Usually, the outcome is only subclinical infection or a mild fever. However, outbreaks of feline disease caused by canine H3N2 IAV with fever, tachypnoea, sneezing, coughing, dyspnoea and lethargy are occasionally noted in shelters. In one such outbreak, the morbidity rate was 100% and the mortality rate was 40%. Recently, avian H7N2 IAV infection occurred in cats in some shelters in the USA, inducing mostly mild respiratory disease. Furthermore, cats are susceptible to experimental infection with the human H3N2 IAV that caused the pandemic in 1968. Several studies indicated that cats worldwide could be infected by H1N1 IAV during the subsequent human pandemic in 2009. In one shelter, severe cases with fatalities were noted. Finally, the highly pathogenic avian H5N1 IAV can induce a severe, fatal disease in cats, and can spread via cat-to-cat contact. 
  • 1.4K
  • 16 Aug 2021
Topic Review
Toxicity of meta-Tyrosine
meta-Tyrosine (m-Tyr) is a non-proteinogenic isomer of p-tyrosine (Tyr) and is an antimetabolite of proteinogenic amino acid phenylalanine (Phe). This compound can be found in animal and plant cells.
  • 1.4K
  • 02 Mar 2022
Topic Review
Pharmacological Treatment in Presbyopia
Pharmacological treatment of presbyopia may be an alternative for those who want a spectacle-free scenario and an easy-to-use method with lower risk of irreversible ocular adverse events. There are two main agents, miotics and lens softeners, investigated as agents for the pharmacological treatment. Miotic agents treat presbyopia by creating a pinhole effect which may increase the depth of focus at all working distances. Lens softeners increase the elasticity of the lens, which is targeted at one of the etiologic mechanisms of presbyopia. 
  • 1.4K
  • 14 Mar 2022
Topic Review
Pharmacological Background of Agave Species
The Agavaceae Endl. Family is distributed in the American continent, among the United States, Central America and the Antilles. In Mexico, approximately 342 species are recognized, and are distributed among eight different genera: Agave L., Beschorneria Kunth, Furcraea Vent., Hesperaloe Engelm., Manfreda Salisb., Polianthes L., Prochnyanthes S. Watson and Yucca L. The Agave genus is mostly distributed in Mexico, where approximately 75% of these species are located.
  • 1.4K
  • 13 Sep 2022
Topic Review
Komagataella phaffii Biotechnology
The need for a more sustainable society has prompted the development of bio-based processes to produce fuels, chemicals, and materials in substitution for fossil-based ones. In this context, microorganisms have been employed to convert renewable carbon sources into various products. The methylotrophic yeast Komagataella phaffii has been extensively used in the production of heterologous proteins. The obligate aerobic yeast Komagataella phaffii is a non-pathogenic certified and generally recognized as a safe (GRAS) microorganism. It is classified in the Saccharomycetales order and Saccharomycetaceae family. 
  • 1.4K
  • 10 Nov 2022
Topic Review
Ethics in the Bible
Ethics in the Bible refers to the system(s) or theory(ies) produced by the study, interpretation, and evaluation of biblical morals, (including the moral code, standards, principles, behaviors, conscience, values, rules of conduct, or beliefs concerned with good and evil and right and wrong), that are found in the Hebrew and Christian Bibles. It comprises a narrow part of the larger fields of Jewish and Christian ethics, which are themselves parts of the larger field of philosophical ethics. Ethics in the Bible is unlike other western ethical theories in that it is seldom overtly philosophical. It presents neither a systematic nor a formal deductive ethical argument. Instead, the Bible provides patterns of moral reasoning that focus on conduct and character in what is sometimes referred to as virtue ethics. This moral reasoning is part of a broad, normative covenantal tradition where duty and virtue are inextricably tied together in a mutually reinforcing manner. The ethics of the Bible have been criticized with some calling it immoral in some of its teachings. Slavery, genocide, supersessionism, the death penalty, violence, patriarchy, sexual intolerance, colonialism, and the problem of evil and a good God, are examples of criticisms of ethics in the Bible. Conversely it has been seen as a cornerstone of both Western culture, and many other cultures across the globe. Concepts such as justice for the widow, orphan and stranger provided inspiration for movements ranging from abolitionism in the 18th and 19th century, the civil rights movement, the Anti-Apartheid Movement, and liberation theology in Latin America.
  • 1.4K
  • 30 Nov 2022
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