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Topic Review
Presynaptic Calcium Channels
Presynaptic Ca2+ entry occurs through voltage-gated Ca2+ (CaV) channels which are activated by membrane depolarization. Depolarization accompanies neuronal firing and elevation of Ca2+ triggers neurotransmitter release from synaptic vesicles. For synchronization of efficient neurotransmitter release, synaptic vesicles are targeted by presynaptic Ca2+ channels forming a large signaling complex in the active zone. The presynaptic CaV2 channel gene family (comprising CaV2.1, CaV2.2, and CaV2.3 isoforms) encode the pore-forming α1 subunit. The cytoplasmic regions are responsible for channel modulation by interacting with regulatory proteins.
  • 1.3K
  • 23 Apr 2021
Topic Review
Brain NMDA Receptors
N-methyl-D-aspartate (NMDA) receptor antagonists such as phencyclidine (PCP), dizocilpine (MK-801) and ketamine have long been considered a model of schizophrenia, both in animals and humans. However, ketamine has been recently approved for treatment-resistant depression, although with severe restrictions. Interestingly, the dosage in both conditions is similar, and positive symptoms of schizophrenia appear before antidepressant effects emerge. Here, we describe the temporal mechanisms implicated in schizophrenia-like and antidepressant-like effects of NMDA blockade in rats, and postulate that such effects may indicate that NMDA receptor antagonists induce similar mechanistic effects, and only the basal pre-drug state of the organism delimitates the overall outcome.
  • 1.3K
  • 10 Jun 2021
Topic Review
Natural Fiber-Reinforced Biocomposites
In the last ten years, environmental consciousness has increased worldwide, leading to the development of eco-friendly materials to replace synthetic ones. Natural fibers are extracted from renewable resources at low cost. Their combination with synthetic polymers as reinforcement materials has been an important step forward in that direction. The sustainability and excellent physical and biological (e.g., biocompatibility, antimicrobial activity) properties of these biocomposites have extended their application to the biomedical field. 
  • 1.3K
  • 30 Jun 2021
Topic Review
Secondary Aroma
Aroma profile is one of the main features for the acceptance of wine. Yeasts and bacteria are the responsible organisms to carry out both, alcoholic and malolactic fermentation. Alcoholic fermentation is in turn, responsible for transforming grape juice into wine and providing secondary aromas. Secondary aroma can be influenced by different factors; however, the influence of the microorganisms is one of the main agents affecting final wine aroma profile. Saccharomyces cerevisiae has historically been the most used yeast for winemaking process for its specific characteristics: high fermentative metabolism and kinetics, low acetic acid production, resistance to high levels of sugar, ethanol, sulfur dioxide and also, the production of pleasant aromatic compounds. Nevertheless, in the last years, the use of non-saccharomyces yeasts has been progressively growing according to their capacity to enhance aroma complexity and interact with S. cerevisiae, especially in mixed cultures.
  • 1.3K
  • 27 May 2021
Topic Review
Long-Term Potentiation Mechanisms of Excitatory and Inhibitory Synapses
Neuronal and glial cells are the main components of the brain. Approximately 50% of the brain is neuronal cells; the other half is glial cells, which all play an important role in the mammalian brain. Billions of neurons are connected and communicate via synapses inextricably linked to behavior, memory, and neurological diseases. Synaptic plasticity is a change in neural connection strength that occurs in response to activity. Reorganization of the structural and functional connections of synapses occurs in response to internal or external stimuli, leading to the strengthening or weakening of synaptic connections via synaptic plasticity. Long-term potentiation (LTP) has been widely used as an ideal model for studying synaptic plasticity, learning, and memory.
  • 1.3K
  • 19 Apr 2023
Topic Review
GPCR
G protein-coupled receptors (GPCRs) are cell surface receptors that respond to a wide variety of stimuli, from light, odorants, hormones, and neurotransmitters to proteins and extracellular calcium. GPCRs represent the largest family of signaling proteins targeted by many clinically used drugs.
  • 1.3K
  • 30 Apr 2021
Topic Review
Melleins
Melleins are 3,4-dihydroisocoumarins mainly produced by fungi, but also by plants, insects and bacteria. These specialized metabolites play important roles in the life cycles of the producers and they are involved in many biochemical and ecological processes.
  • 1.3K
  • 09 Jun 2021
Topic Review
Thoracic Aortic Aneurysms and Dissection
Thoracic aortic aneurysm and dissection (TAAD) affects many patients globally and has high mortality rates if undetected. Once thought to be solely a degenerative disease that afflicted the aorta due to high pressure and biomechanical stress, extensive investigation of the heritability and natural history of TAAD has shown a clear genetic basis for the disease.
  • 1.3K
  • 28 Jun 2021
Topic Review
Sample Pretreatment of Microfluidic Devices
The difficulty of sample pretreatment/preparation in food testing is much higher than that for human biological samples. For example, whole blood analysis and diagnosis tests usually require only centrifugation to separate the blood cells and plasma for detection. By contrast, when detecting acidic preservatives in food samples, for example, it is necessary to homogenize the sample first and then extract the test substance by steam distillation before detection can be performed. As a result, sample processing in traditional food detection methods usually involves a high cost, a long process, and the use of multiple equipment. This section therefore reviews the pretreatment methods proposed in the literature for milk sample analysis using compact and low-cost microfluidic devices. Broadly speaking, pretreatment methods on microfluidic platforms fall into three main categories, namely separation, extraction, and concentration/amplification.
  • 1.3K
  • 19 May 2021
Topic Review
Endotoxin Activity Assay
Endotoxin, also referred to as lipopolysaccharide (LPS), is a potent stimulator of the inflammatory cascade which may progress to sepsis and septic shock. The term endotoxic septic shock has been used for patients who have a clinical phenotype that is characterized by high endotoxin activity in addition to a high burden of organ failure; especially a pattern of organ failure including hepatic dysfunction, acute kidney injury, and various forms of endothelial dysfunction. Endotoxic septic shock has been a target for drug therapy for decades with no success. A likely barrier to their success was the inability to quantify endotoxin in the bloodstream. The Endotoxin Activity Assay (EAA) is positioned to change this landscape. In addition, medical devices using adsorptive technology in an extra-corporeal circulation has been shown to remove large quantities of endotoxin from the bloodstream. 
  • 1.3K
  • 16 Nov 2023
Topic Review
Interstitial Telomeric-like Repeats (ITR)
Interstitial telomeric repeat (ITR) sites, also known as interstitial telomeric sequences (ITSs), consist of tandem repeats of telomeric motifs that are located within intrachromosomal regions, including repeats located close to the centromeres and the ones found between the centromeres and the telomeres.
  • 1.3K
  • 10 Dec 2021
Topic Review
Preeclampsia and Therapeutic Approaches
Preeclampsia (PE) is a serious pregnancy complication, affecting about 5–7% of pregnancies worldwide and is characterized by hypertension and damage to multiple maternal organs, primarily the liver and kidneys. PE usually begins after 20 weeks’ gestation and, if left untreated, can lead to serious complications and lifelong disabilities—even death—in both the mother and the infant. As delivery is the only cure for the disease, treatment is primarily focused on the management of blood pressure and other clinical symptoms. The pathogenesis of PE is still not clear. Abnormal spiral artery remodeling, placental ischemia and a resulting increase in the circulating levels of vascular endothelial growth factor receptor-1 (VEGFR-1), also called soluble fms-like tyrosine kinase-1 (sFlt-1), are believed to be among the primary pathologies associated with PE. sFlt-1 is produced mainly in the placenta during pregnancy and acts as a decoy receptor, binding to free VEGF (VEGF-A) and placental growth factor (PlGF), resulting in the decreased bioavailability of each to target cells. Despite the pathogenic effects of increased sFlt-1 on the maternal vasculature, recent studies from our laboratory and others have strongly indicated that the increase in sFlt-1 in PE may fulfill critical protective functions in preeclamptic pregnancies.
  • 1.3K
  • 11 Jun 2021
Topic Review
Calomys callosus
The appearance and spread of parasitic diseases around the world aroused the interest of the scientific community to discover new animal models for improving the quality and specificity of surveys. Calomys callosus is a rodent native to South America, an easy handling model, with satisfactory longevity and reproducibility. C. callosus is susceptible to toxoplasmosis and can be used as experimental model for the study the pathogenesis, treatment, vertical transmission, and ocular toxoplasmosis. C. callosus can also be used to study cutaneous and visceral leishmaniasis, as the animals present cutaneous lesions, as well as parasites in the organs. C. callosus has epidemiological importance in Chagas disease, and since it is a Trypanosoma cruzi natural host in which rodents show high parasitemia and lethality, they are also effective as a model of congenital transmission. In the study of schistosomiasis, Schistosoma mansoni was proven to be a C. callosus natural host; thus, this rodent is a great model for fibrosis, hepatic granulomatous reaction, and celloma associated with lymphomyeloid tissue (CALT) during S. mansoni infection.
  • 1.3K
  • 01 Apr 2022
Topic Review
Human Coronavirus Cell Receptors
Coronaviruses interact with protein or carbohydrate receptors through their spike proteins to infect cells. Even if the known protein receptors for these viruses have no evolutionary relationships, they do share ontological commonalities that the virus might leverage to exacerbate the pathophysiology. ANPEP/CD13, DPP IV/CD26, and ACE2 are the three protein receptors that are known to be exploited by several human coronaviruses. These receptors are moonlighting enzymes involved in several physiological processes such as digestion, metabolism, and blood pressure regulation; moreover, the three proteins are expressed in kidney, intestine, endothelium, and other tissues/cell types.
  • 1.3K
  • 03 Apr 2023
Topic Review
Functionalized Mesoporous Thin Films
Functionalized thin films of mesoporous silica and titania can be used as scaffolds with properties as diverse as promotion of cell growth, inhibition of biofilms formation, or development of sensors based on immobilized enzymes. The possibility to pattern them increase their appeal as they can be incorporated into devices and can be tailored both with respect to architecture and functionalization. In fact, selective surface manipulation is the ground for the fabrication of advanced micro devices that combine standard micro/nanofluids with functional materials.
  • 1.3K
  • 30 Jun 2021
Topic Review
Spider–Plant Associations
Spiders are ubiquitous generalist predators playing an important role in regulating insect populations in many ecosystems. Traditionally they have not been thought to have strong influences on, or interactions with plants. However, this is slowly changing as several species of cursorial spiders have been reported engaging in either herbivory or inhabiting only one, or a handful of related plant species. 
  • 1.3K
  • 15 Mar 2023
Topic Review
Phytochemicals in Redox Homeostasis
Redox homeostasis, a dynamic process ensuring a balance between cellular oxidizing and reducing reactions, is crucial for maintaining healthy cellular physiology and regulating many biological processes, requiring continuous monitoring and fine-tuning. Reactive species play a critical role in intra/intercellular signaling, and each cell has a specific system guarding cellular redox homeostasis. Reactive oxygen species (ROS) signaling and oxidative stress are involved in cancer initiation and progression.
  • 1.3K
  • 24 Apr 2023
Topic Review
Obesity, AR Signaling and BC
Obesity is an increasing health challenge and is recognized as a breast cancer risk factor. Although obesity-related breast cancer mechanisms are not fully understood, this association has been linked to impaired hormone secretion by the dysfunctional obese adipose tissue (hyperplasic and hypertrophic adipocytes). Among these hormones, altered production of androgens and adipokines is observed, and both, are independently associated with breast cancer development. 
  • 1.3K
  • 21 Jun 2021
Topic Review
Probiotics in Fish Nutrition
Probiotics are live microbial additives that have a beneficial effect on the host by (1) modifying the host-associated microbial community, (2) ensuring improved use of the feed or enhancing its nutritional value, (3) enhancing the host response towards disease, and/or (4) improving the quality of its ambient environment.
  • 1.3K
  • 21 Jun 2021
Topic Review
NMDA Receptors in Astrocytes
Studies of the last two decades have demonstrated the presence in astrocytic cell membranes of N-methyl-d-aspartate (NMDA) receptors (NMDARs), albeit their abundance in astrocytes appears to be strikingly lower than of other glutamate (Glu) receptor classes. Recent advancements in visualization techniques have enabled convincing demonstration of the activation of astrocytic NMDARs directly in brain slices and in acutely isolated or cultured astrocytes, by monitoring intracellular calcium increase. Astrocytic NMDARs are activated by mutually unexclusive ionotropic and metabotropic mechanisms.
  • 1.3K
  • 30 Apr 2021
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