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Topic Review
Mechanisms of Atrial Fibrillation
Atrial fibrillation (AF) is a very common arrhythmia that mainly affects older individuals. The mechanism of atrial fibrillation is complex and is related to the pathogenesis of trigger activation and the perpetuation of arrhythmia. The pulmonary veins in the left atrium arei confirm that onfirm the most common triggers due to their distinct anatomical and electrophysiological properties.
  • 979
  • 12 Jun 2023
Topic Review
Subclinical Acute Kidney Injury in Patients with COVID-19
Since the outbreak of COVID-19 disease, a bidirectional interaction between kidney disease and the progression of COVID-19 has been demonstrated. Kidney disease is an independent risk factor for mortality of patients with COVID-19 as well as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection leading to the development of acute kidney injury (AKI) and chronic kidney disease (CKD) in patients with COVID-19. However, the detection of kidney damage in patients with COVID-19 may not occur until an advanced stage based on the current clinical blood and urinary examinations. Some studies have pointed out the development of subclinical acute kidney injury (subAKI) syndrome with COVID-19. This syndrome is characterized by significant tubule interstitial injury without changes in the estimated glomerular filtration rate. Despite the complexity of the mechanism(s) underlying the development of subAKI, the involvement of changes in the protein endocytosis machinery in proximal tubule (PT) epithelial cells (PTECs) has been proposed.
  • 979
  • 29 Nov 2022
Topic Review
Skull Vibration Induced Nystagmus
Skull vibration induced nystagmus (SVIN) is a dramatic clinical observation—if a vibrator is applied to either mastoid of a patient with a total unilateral vestibular loss (TUVL) and switched on at a frequency of 100 Hz and at moderate intensity (about the strength a body massager) the patient immediately has a nystagmus, mainly horizontal, with the clinically obvious quick phases (QPs) beating away from the lesioned ear.
  • 972
  • 25 Nov 2021
Topic Review
PPARs and Their Neuroprotective Effects in Parkinson’s Disease
Peroxisome proliferator-activated receptor (PPAR) belong to subgroup 1 of the nuclear receptor superfamily. They are known to form heterodimers with the retinoid X receptors (RXRs) when activated by endogenous or exogenous ligands and to bind to a co-activator such as PGC-1α.
  • 970
  • 22 Feb 2023
Topic Review
Mycotoxins Affect Animals’ Oxidative Status
Mycotoxins appear to be the “Achilles’ heel” of the agriculture sector inducing enormous economic losses and representing a severe risk to the health of humans and animals. Although novel determination protocols have been developed and legislation has been implemented within Europe, the side effects of mycotoxins on the homeostatic mechanisms of the animals have not been extensively considered. The findings support the idea that the antioxidant systems in both monogastrics and ruminants are challenged under the detrimental effect of mycotoxins by increasing the toxic lipid peroxidation by-product malondialdehyde (MDA) and inhibiting the activity of antioxidant defense mechanisms.The degree of oxidative stress is related to the duration of contamination, co-contamination, the synergetic effects, toxin levels, animal age, species, and productive stage. Since the damaging effects of MDA and other by-products derived by lipid peroxidation as well as reactive oxygen species have been extensively studied on human health, a more integrated monitoring mechanism (which will take into account the oxidative stability) is urgently required to be implemented in animal products.
  • 967
  • 16 Oct 2021
Topic Review
Roles of Cav1.2 in Pathogenesis of Hypertension-Related Disorders
Blood pressure is determined by cardiac output and peripheral vascular resistance. The L-type voltage-gated Ca2+ (Cav1.2) channel in small arteries and arterioles plays an essential role in regulating Ca2+ influx, vascular resistance, and blood pressure. Hypertension and preeclampsia are characterized by high blood pressure. In addition, diabetes has a high prevalence of hypertension. The etiology of these disorders remains elusive, involving the complex interplay of environmental and genetic factors. Common to these disorders are oxidative stress and vascular dysfunction. Reactive oxygen species (ROS) derived from NADPH oxidases (NOXs) and mitochondria are primary sources of vascular oxidative stress, whereas dysfunction of the Cav1.2 channel confers increased vascular resistance in hypertension. 
  • 966
  • 20 Jan 2023
Topic Review
Pharmaceutical Drug and Metabolic Adaptions/Reprogramming in β-Cells
Islet inflammation in T1DM is characterized by leukocyte infiltrates, in particular macrophages and T-cells which damage β-cells by release of cytokines, ROS and NO and also activation of death-receptor-mediated death pathways and subsequent phagocytosis. Production of cytokines such as INF-γ, TNFα and IL-1β act in synergy to promote elevation in concentration and increase in activity of NADPH oxidase and iNOS consequently increasing the formation of products including ROS and NO, respectively. The mechanism of action of INF-γ, TNFα and IL-1β involves stimulation of transcription factors including NFκB (in mouse islet β-cells).
  • 965
  • 29 Mar 2022
Topic Review
Galectin-3 in Kidney Diseases
Galectin-3 (Gal-3) is a 30KDa lectin implicated in multiple pathophysiology pathways including renal damage and fibrosis. Gal-3 binds β-galactoside through its carbohydrate-recognition domain.
  • 965
  • 08 Apr 2022
Topic Review
Obesity and Aging
Today, inactivity and high-calorie diets contribute to the development of obesity and premature aging. In addition, the population of elderly people is growing due to improvements in healthcare management. Obesity and aging are together key risk factors for non-communicable diseases associated with several co-morbidities and increased mortality, with a major impact on skeletal muscle defect and/or poor muscle mass quality.
  • 964
  • 21 Oct 2022
Topic Review
Climate Change and Its Impact on Crops
Plants are a highly advanced kingdom of living organisms on the earth. They survive under all climatic and weather variabilities, including low and high temperature, rainfall, radiation, less nutrients, and high salinity. Even though they are adapted to various environmental factors, which are variable, the performance of a crop will be compensated under sub/supra optimal conditions. 
  • 959
  • 22 Dec 2022
Topic Review
Amyotrophic Lateral Sclerosis with the Enteric Nervous System
Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease affecting motor neurons in the spinal cord, cerebral cortex, and medulla oblongata. Most patients present a clinical phenotype of classic ALS—with predominant atrophy, muscle weakness, and fasciculations—and survival of 3 to 5 years following diagnosis. There are two types of ALS: the familial form with genetic involvement, and the sporadic form with a multifactorial origin. ALS pathophysiology is characterized by involvement of multiple processes, including oxidative stress, glutamate excitotoxicity, and neuroinflammation. Moreover, it is proposed that conditioning risk factors affect ALS development—such as susceptibility to neurodegeneration in motor neurons, the intensity of performed physical activity, and intestinal dysbiosis with involvement of the enteric nervous system—which supports the existing theories of disease generation.
  • 958
  • 14 Apr 2023
Topic Review
Colonic Fluid and Electrolyte Transport 2022
The colon is the final segment of the vertebrate digestive system, where fluid and electrolyte transport can be modulated to maintain intestinal and whole-body homeostasis. The expression and activity of many ion transporters in the colon are controlled by a complex and delicate homeostatic ion balance, such that hormones (i.e., aldosterone and angiotensin), pathophysiological inhibitors (i.e., Cholera and STa toxins) and diseases (i.e., metastatic changes) prompt surprisingly distinct responses between the proximal and distal colon segments. Modern and classical experimental methods, such as real-time reverse transcription polymerase chain reaction (RT-PCR), Ussing chambers, genome-wide analysis, next-generation epigenetic sequencing analysis, immunocytochemistry, patch clamping, and siRNA, have allowed the localization, characterization, and measurement of ion transporters. The differential expression and regulation of transporters, described using the following methods, is what gives the proximal and distal colon, apical and basolateral epithelial membranes, and crypts and surface cells unique homeostatic functions and responses to various drugs, hormones, and immune factors.
  • 951
  • 06 Jun 2022
Topic Review
Pathophysiological Response to CnTX Voltage-Gated Channel Modulation
Voltage-gated ion channels are plasma membrane proteins that generate electrical signals following a change in the membrane voltage.
  • 951
  • 14 Jun 2022
Topic Review
Pyrophosphate in Vascular Calcification
In vertebrates, plasma and other extracellular fluids are supersaturated with phosphate and calcium, causing a tendency for spontaneous calcium-phosphate precipitation. Therefore, the synthesis of calcium phosphate deposition inhibitors is essential for survival, including pyrophosphate and several proteins.
  • 948
  • 21 Dec 2021
Topic Review
Dopamine Levels and Metabolism in the Heart
Dopamine has effects on the mammalian heart. These effects can include an increase in the force of contraction, and an elevation of the beating rate and the constriction of coronary arteries. Depending on the species studied, positive inotropic effects were strong, very modest, or absent, or even negative inotropic effects occurred.
  • 945
  • 06 Sep 2023
Topic Review
Neuroglobin in Retinal Neurodegeneration
Retinal neurodegeneration affects an increasing number of people worldwide causing vision impairments and blindness, reducing quality of life, and generating a great economic challenge. Due to the complexity of the tissue, and the diversity of retinal neurodegenerative diseases in terms of etiology and clinical presentation, so far, there are no cures. The discovering of the intracellular monomeric globin neuroglobin (NGB), found at high concentration in the retina, has opened new possibilities for the treatment of retinal disease.
  • 944
  • 30 Nov 2021
Topic Review
Role of Adenosine in Extreme Oxygen Pressure  Exposure
At high altitudes, the increased adenosine concentration contributes to brain protection against hypoxia through various mechanisms such as stimulation of glycogenolysis for ATP production, reduction in neuronal energy requirements, enhancement in 2,3-bisphosphoglycerate production, and increase in cerebral blood flow secondary to vasodilation of cerebral arteries. In the context of mountain illness, the increased level of A2AR expression leads to glial dysfunction through neuroinflammation and is involved in the pathogenesis of neurological disorders. Nonetheless, a high level of adenosine concentration can protect against high-altitude pulmonary edema via a decrease in pulmonary arterial pressure. The adenosinergic system is also involved in the acclimatization phenomenon induced by prolonged exposure to altitude hypoxia. During hyperoxic exposure, decreased extracellular adenosine and low A2A receptor expression contribute to vasoconstriction. The resulting decrease in cerebral blood flow is considered a preventive phenomenon against cerebral oxygen toxicity through the decrease in oxygen delivery to the brain. With regard to lung oxygen toxicity, hyperoxia leads to an increase in extracellular adenosine, which acts to preserve pulmonary barrier function. Changes in the adenosinergic system induced by exposure to extreme oxygen partial pressures frequently have a benefit in decreasing the risk of adverse effects.
  • 944
  • 28 Oct 2022
Topic Review
Current Techniques in Drug Delivery across Blood–Brain Barrier
Non-invasive drug delivery across the blood-brain barrier (BBB) represents a significant advancement in treating neurological diseases. The BBB is a tightly packed layer of endothelial cells that shields the brain from harmful substances in the blood, allowing necessary nutrients to pass through. It is a highly selective barrier, which poses a challenge to delivering therapeutic agents into the brain. Several non-invasive procedures and devices have been developed or are currently being investigated to enhance drug delivery across the BBB.
  • 940
  • 27 Nov 2023
Topic Review
Follicle-Stimulating Hormone Extra-Gonadal and Non-Canonical Effects in Males
Recombinant follicle-stimulating hormone (FSH) is commonly used for the treatment of female and male infertility FSH is composed of an α subunit, shared with other hormones, and a β subunit, which confers specificity of biological action by interacting with its surface receptor (FSHR), predominantly located in granulosa and Sertoli cells. Beyond the well-known effects of FSH on reproductive functions the attention has recently focused on the extra-gonadal effects of FSH, specifically on bone and adipose tissue metabolsm, the cardiovascular and immune systems and the prostate gland. FSH could therefore be involved in several pathological and physiological processes, which are still not completely understood.
  • 939
  • 16 Jun 2023
Topic Review
Growth and Nutritional Quality of Lemnaceae
This entry focuses on recently characterized traits of the aquatic floating plant Lemna with an emphasis on its capacity to combine rapid growth with the accumulation of high levels of the essential human micronutrient zeaxanthin, due to an unusual pigment composition not seen in other fast-growing plants. In addition, Lemna’s response to elevated atmospheric carbon dioxide was evaluated in the context of the source–sink balance between plant sugar production and consumption. These and other traits of Lemnaceae are compared with those of other floating aquatic plants as well as terrestrial plants adapted to different environments. It was concluded that the unique features of aquatic plants reflect adaptations to the freshwater environment including rapid growth, high productivity, and exceptionally strong accumulation of high-quality vegetative storage protein and essential human antioxidant micronutrients. It was further concluded that the insensitivity of growth rate to environmental conditions and plant source–sink imbalance may allow duckweeds to take advantage of elevated atmospheric carbon dioxide levels via particularly strong stimulation of biomass production and either no (under favorable nutrient supply), or only minor (under limiting nutrient supply), declines in the growth of new tissue.
  • 934
  • 24 Jan 2022
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