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Topic Review
Surgery Benefit Pipkin Type I Femoral Head Fractures
Femoral head fractures are rare injuries with or without traumatic dislocations. The management of these fractures is crucial to prevent the development of severe complications and to achieve optimal functional outcomes. Wide treatment options for Pipkin 1 femoral head fractures range from fragment excision, fixation following open reduction with internal fixation, or conservative treatment such as close reduction alone after fracture dislocation. 
  • 1.2K
  • 26 Jan 2022
Topic Review
Statin Residual Cardiovascular Disease Risk
Several randomized, double blind, placebo-controlled trials (RCTs) have demonstrated that low-density lipoprotein cholesterol (LDL-C) lowering by using statins, including high-doses of strong statins, reduced the development of cardiovascular disease (CVD). However, among the eight RCTs which investigated the effect of statins vs. placebos on the development of CVD, 56–79% of patients had the residual CVD risk after the trials. In three RCTs which investigated the effect of a high dose vs. a usual dose of statins on the development of CVD, 78–87% of patients in the high-dose statin arms still had the CVD residual risk after the trials. An analysis of the characteristics of patients in the RCTs suggests that elevated triglyceride (TG) and reduced high-density lipoprotein cholesterol (HDL-C), the existence of obesity/insulin resistance, and diabetes may be important metabolic factors which determine the statin residual CVD risk. 
  • 1.2K
  • 06 Apr 2022
Topic Review
Role of Raf Family in Biology
The Raf kinase family consists of three isoforms, C-Raf/Raf-1, B-Raf and A-Raf. They are located directly downstream of Ras and upstream of MEK1/2. Since the discovery of v-Ras, v-Raf and ERK and the connection of this regulatory hub with oncogenesis, tremendous efforts have been invested in the elucidation of the mechanisms underlying the activation of Raf kinases. The Raf/MEK/ERK pathway is the first and clearly defined mitogenic pathway whose signal is invoked by extracellular mitogenic ligands and serves as a framework for other MAPK pathways. Among three isoforms of the Raf family, B-Raf is the only one that has so far been found mutated in many types of cancers. As all of the Raf family members directly act downstream of Ras, C-Raf and A-Raf are also important factors contributing to oncogenesis, either mediating the effects of mutated Ras or participating in oncogenic B-Raf-mediated pathogenesis. Thus, the development of Raf inhibitors has been a focus in cancer therapy.
  • 1.2K
  • 19 May 2022
Topic Review
Effects of Exercise on the Alzheimer’s Disease
Alzheimer’s disease (AD) is a progressive degenerative disorder and a leading cause of dementia in the elderly. The etiology of AD is multifactorial, including an increased oxidative state, deposition of amyloid plaques, and neurofibrillary tangles of the tau protein. 
  • 1.2K
  • 06 Jul 2022
Topic Review
Outflow Tract Valves of the Vertebrate Heart
The anatomical elements that in humans guard the unidirectional blood flow from the cardiac ventricles to the aortic and pulmonary arteries are the arterial (semilunar) valves. The valve that prevents blood backflow from the aorta to the left ventricle is the aortic valve, while that which performs this function between the pulmonary artery and the right ventricle is the pulmonary or pulmonic valve. The main medical interest in arterial valves is that their congenital malformations and diseases over a lifetime are clinically relevant. Although both valves are subject to similar complications, those affecting the aortic valve cause the most severe effects.
  • 1.2K
  • 04 Oct 2022
Topic Review
Patients with Bicuspid Aortopathy and Aortic Dilatation
Bicuspid aortic valve (BAV) is the most frequent congenital cardiac disease. Alteration of ascending aorta diameter is a consequence of shear stress alterations due to haemodynamic abnormalities developed from inadequate valve cusp coaptation.
  • 1.2K
  • 25 Oct 2022
Topic Review
Agit-Train
An agit-train (Russian: агитпоезд) was a locomotive engine with special auxiliary cars outfitted for propaganda purposes by the Bolshevik government of Soviet Russia during the time of the Russian Civil War, War Communism, and the New Economic Policy. Brightly painted and carrying on board a printing press, government complaint office, printed political leaflets and pamphlets, library books, and a mobile movie theater, agit-trains traveled the rails of Russia , Siberia, and the Ukraine in an attempt to inculcate the values and program of the new revolutionary government to a scattered and isolated peasantry. Launched in August 1918, agit-trains — and their close counterparts, the urban agit-streetcar (Russian: агиттрамвай) and the aquatic agit-boat (Russian: агитпарaход) — continued in limited use throughout the 1920s. The agit-train concept was revived during the years of World War II as a mechanism for the direct spread of information during a time when ordinary means of communication and government control structures between the center and the periphery had faltered.
  • 1.2K
  • 26 Oct 2022
Topic Review
Anchisauridae
Anchisaurus is a genus of basal sauropodomorph dinosaur. It lived during the Early Jurassic Period, and its fossils have been found in the red sandstone of the Portland Formation, northeastern United States , which was deposited from the Hettangian age into the Sinemurian age, between about 200 and 195 million years ago. Until recently it was classed as a member of Prosauropoda. The genus name Anchisaurus comes from the Greek αγχι (agkhi) anchi-; "near, close" + Greek σαυρος (sauros); "lizard". Anchisaurus was coined as a replacement name for "Amphisaurus", which was itself a replacement name for Hitchcock's "Megadactylus", both of which had already been used for other animals.
  • 1.2K
  • 27 Oct 2022
Topic Review
H2 Antagonist
H2 antagonists, sometimes referred to as H2RAs and also called H2 blockers, are a class of medications that block the action of histamine at the histamine H2 receptors of the parietal cells in the stomach. This decreases the production of stomach acid. H2 antagonists can be used in the treatment of dyspepsia, peptic ulcers and gastroesophageal reflux disease. They have been surpassed by proton pump inhibitors (PPIs); the PPI omeprazole was found to be more effective at both healing and alleviating symptoms of ulcers and reflux oesophagitis than the H2 blockers ranitidine and cimetidine. H2 antagonists are a type of antihistamine, although in common use the term "antihistamine" is often reserved for H1 antagonists, which relieve allergic reactions. Like the H1 antagonists, some H2 antagonists function as inverse agonists rather than receptor antagonists, due to the constitutive activity of these receptors. The prototypical H2 antagonist, called cimetidine, was developed by Sir James Black at Smith, Kline & French – now GlaxoSmithKline – in the mid-to-late 1960s. It was first marketed in 1976 and sold under the trade name Tagamet, which became the first blockbuster drug. The use of quantitative structure-activity relationships (QSAR) led to the development of other agents – starting with ranitidine, first sold as Zantac, which has fewer adverse effects and drug interactions and is more potent. H2 blockers, which all end in "-tidine," are not the same as H1 receptor antagonists, which relieve allergy symptoms.
  • 1.2K
  • 31 Oct 2022
Topic Review
AFVG
AFVG (standing for Anglo-French Variable Geometry) was a 1960s project for supersonic multi-role combat aircraft with a variable-geometry wing,[N 1] jointly developed by British Aircraft Corporation in the United Kingdom and Dassault Aviation of France. The project was borne out of ambitions to produce a viable combat aircraft that made use of the variable-sweep wing, as well as to promote wider cooperative efforts between France and the United Kingdom. However, neither Dassault not the French Air Force were particularly keen on the AFVG; the project was further impacted by repeated specification changes and indecision for what roles that the AFVG was to be tasked with on the part of Britain. In mid-1967, British requirements settled upon adopting the AFVG for the Royal Air Force (RAF) for the strike role in the place of the cancelled BAC TSR-2 strike bomber. The project was cancelled in June 1967, when the French Government withdrew from participation. However, the cancellation was not the end of work on the proposed design. BAC modified the specification to solely satisfy Royal Air Force (RAF) needs, reconfiguring the design as the UKVG and sought out new partners to procure the aircraft, which ultimately emerged as the Anglo-German-Italian consortium-funded MRCA (Panavia Tornado), a variable-geometry wing fighter/strike aircraft.
  • 1.2K
  • 28 Nov 2022
Topic Review
Nano and Microemulsions for Depression and Anxiety Treatment
Most drugs used for the treatment of depression, anxiety and related disorders have low absorption, high metabolism, low brain targeting and/or low water solubility, which can make it hard to formulate them at high strength and can also lead to decreased bioavailability. Incorporating these drugs into nanometric emulsions can solve these issues. Nanometric emulsions were able to increase drug strength up to 20,270-fold (compared to aqueous solubility). The formulations showed droplet size, polydispersity index, zeta potential, viscosity, osmolality, pH, in vitro drug release and ex vivo drug permeation as adequate for the intended effect and administration route.
  • 1.2K
  • 23 Dec 2022
Topic Review
Flexible Current Control Strategies Applied to LVRT Capability
Distributed power generation plays a critical role in the stability and reliability of modern power systems. Due to the rapid growth of renewable energy generation, the requirements of the transmission and distribution system operators are becoming more stringent. Among these requirements, one of the most important is the Low-Voltage Ride-Through (LVRT) capability, which demands that the inverters remain connected to the grid and provide support during voltage sags. For this purpose, flexible current control algorithms stand out because they can manage unbalanced voltages and simultaneously achieve other control objectives.
  • 1.2K
  • 10 Feb 2023
Topic Review
Biosurfactants as Multifunctional Remediation Agents of Environmental Pollutants
Fuel and oil spills during the exploration, refining, and distribution of oil and petrochemicals are primarily responsible for the accumulation of organic pollutants in the environment. The reduction in contamination caused by hydrocarbons, heavy metals, oily effluents, and particulate matter generated by industrial activities and the efficient recovery of oil at great depths in an environmentally friendly way pose a challenge, as recovery and cleaning processes require the direct application of surface-active agents, detergents, degreasers, or solvents, often generating other environmental problems due to the toxicity and accumulation of these substances. Thus, the application of natural surface-active agents is an attractive solution. Due to their amphipathic structures, microbial surfactants solubilize oil through the formation of small aggregates (micelles) that disperse in water, with numerous applications in the petroleum industry. Biosurfactants have proven their usefulness in solubilizing oil trapped in rock, which is a prerequisite for enhanced oil recovery (EOR). Biosurfactants are also important biotechnological agents in anti-corrosion processes, preventing incrustations and the formation of biofilms on metallic surfaces, and are used in formulations of emulsifiers/demulsifiers, facilitate the transport of heavy oil through pipelines, and have other innovative applications in the oil industry. The use of natural surfactants can reduce the generation of pollutants from the use of synthetic detergents or chemical solvents without sacrificing economic gains for the oil industry.
  • 1.2K
  • 15 Feb 2023
Topic Review Peer Reviewed
Synaptosomes: A Functional Tool for Studying Neuroinflammation
Synaptosomes are subcellular components isolated from nerve terminations that can be prepared by homogenizing brain tissue in isotonic sucrose solution followed by appropriate centrifugation. Their preparation technique has a long history since synaptosomes were first isolated from nerve endings and described by Gray and Whittaker in 1962. The preparation of synaptosomes produces presynaptic boutons alone or in combination with fragments of postsynaptic membranes. Interestingly, synaptosomes contain organelles and vesicles that express native channels, receptors, and transporters. At 37 °C, these isolated nerve endings are metabolically active and synthesize and release neurotransmitters. They are actively used to investigate neurotransmission, its actors, and the mechanisms of neurotransmitter release. To date, many functional and non-functional applications of synaptosomes have been documented. Due to their versatility, synaptosomes have been actively used to study neuroinflammatory processes.
  • 1.2K
  • 14 Nov 2023
Topic Review
Halloysite-TiO2 Nanocomposites for Water Treatment
Halloysite nanotubes (HNTs) are clay minerals with a tubular structure that can be used for many different applications in place of carbon nanotubes. Indeed, HNTs display low/non-toxicity, are biocompatible, and can be easily prepared. Moreover, the aluminum and silica groups present on HNTs’ inner and outer surfaces facilitate the interaction with various functional agents, such as alkalis, organosilanes, polymers, surfactants, and nanomaterials.
  • 1.2K
  • 16 May 2023
Topic Review
Cannabis sativa Bioactive Compounds in Colorectal Cancer
Cannabis sativa is a multipurpose plant that has been used in medicine for centuries. Considerable research has focused on the bioactive compounds of this plant, particularly cannabinoids and terpenes. Among other properties, these compounds exhibit antitumor effects in several cancer types, including colorectal cancer (CRC). Cannabinoids show positive effects in the treatment of CRC by inducing apoptosis, proliferation, metastasis, inflammation, angiogenesis, oxidative stress, and autophagy. Terpenes, such as β-caryophyllene, limonene, and myrcene, have also been reported to have potential antitumor effects on CRC through the induction of apoptosis, the inhibition of cell proliferation, and angiogenesis. In addition, synergy effects between cannabinoids and terpenes are believed to be important factors in the treatment of CRC. 
  • 1.2K
  • 18 May 2023
Topic Review
Biomedical Applications of Chitosan
Chitosan, a biocompatible and biodegradable polysaccharide derived from chitin, has surfaced as a material of promise for drug delivery and biomedical applications. Different chitin and chitosan extraction techniques can produce materials with unique properties, which can be further modified to enhance their bioactivities. Chitosan-based drug delivery systems have been developed for various routes of administration, including oral, ophthalmic, transdermal, nasal, and vaginal, allowing for targeted and sustained release of drugs. Additionally, chitosan has been used in numerous biomedical applications, such as bone regeneration, cartilage tissue regeneration, cardiac tissue regeneration, corneal regeneration, periodontal tissue regeneration, and wound healing. Moreover, chitosan has also been utilized in gene delivery, bioimaging, vaccination, and cosmeceutical applications. Modified chitosan derivatives have been developed to improve their biocompatibility and enhance their properties, resulting in innovative materials with promising potentials in various biomedical applications.
  • 1.2K
  • 05 Jul 2023
Topic Review
Migraine and Diets
Migraine ranks among the most prevalent neurological conditions, is a major cause of socio-economic and health problems worldwide, and affects approximately 12% of the population. Repeated migraine attacks can make sufferers physically, mentally, and socially incapacitated for several days. Nutrition and dietary triggers may be an important factor in migraine prevention since it is known that migraine attacks can be triggered by certain dietary compounds.
  • 1.2K
  • 09 Oct 2023
Topic Review
Renewable Energy and Decarbonization in Canadian Mining Industry
Mining in Canada stands as one of the most energy-intensive sectors, playing a pivotal role as a significant provider of copper, nickel, and cobalt to the international market. Anticipated growth in the global population, coupled with the transition of several low-income economies to middle-income status, is poised to escalate the demand for essential raw materials. This surge in demand is expected to drive an increase in energy consumption across various stages of the Canadian mining industry, encompassing exploration, extraction, processing, and refining. Due to their geographical constraints, most Canadian mining operations rely heavily on fossil fuels such as diesel and heavy fuel. Considering the global shift towards decarbonization and the pursuit of net-zero emission targets, exploring avenues for adopting electrification solutions and integrating renewable energy technologies, particularly in sizable surface mines, is imperative.
  • 1.2K
  • 13 Nov 2023
Topic Review
Time Balance and Family Functioning
Family functioning, understood as cohesion and adaptability, is critical in families with adolescent children, given the changes that this stage implies at the family level. Time perspective is one variable that can facilitate better family functioning through the way people give meaning to the process they live.
  • 1.2K
  • 15 Jan 2024
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